diff options
Diffstat (limited to 'mm/page_alloc.c')
| -rw-r--r-- | mm/page_alloc.c | 9122 |
1 files changed, 4201 insertions, 4921 deletions
diff --git a/mm/page_alloc.c b/mm/page_alloc.c index d295c9bc01a8..822e05f1a964 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1,3 +1,4 @@ +// SPDX-License-Identifier: GPL-2.0-only /* * linux/mm/page_alloc.c * @@ -17,65 +18,154 @@ #include <linux/stddef.h> #include <linux/mm.h> #include <linux/highmem.h> -#include <linux/swap.h> #include <linux/interrupt.h> -#include <linux/pagemap.h> #include <linux/jiffies.h> -#include <linux/memblock.h> #include <linux/compiler.h> #include <linux/kernel.h> #include <linux/kasan.h> +#include <linux/kmsan.h> #include <linux/module.h> #include <linux/suspend.h> -#include <linux/pagevec.h> -#include <linux/blkdev.h> -#include <linux/slab.h> #include <linux/ratelimit.h> #include <linux/oom.h> #include <linux/topology.h> #include <linux/sysctl.h> #include <linux/cpu.h> #include <linux/cpuset.h> +#include <linux/pagevec.h> #include <linux/memory_hotplug.h> #include <linux/nodemask.h> -#include <linux/vmalloc.h> #include <linux/vmstat.h> -#include <linux/mempolicy.h> -#include <linux/memremap.h> -#include <linux/stop_machine.h> -#include <linux/sort.h> -#include <linux/pfn.h> -#include <linux/backing-dev.h> #include <linux/fault-inject.h> -#include <linux/page-isolation.h> -#include <linux/page_ext.h> -#include <linux/debugobjects.h> -#include <linux/kmemleak.h> #include <linux/compaction.h> #include <trace/events/kmem.h> #include <trace/events/oom.h> #include <linux/prefetch.h> #include <linux/mm_inline.h> +#include <linux/mmu_notifier.h> #include <linux/migrate.h> -#include <linux/hugetlb.h> -#include <linux/sched/rt.h> #include <linux/sched/mm.h> #include <linux/page_owner.h> -#include <linux/kthread.h> +#include <linux/page_table_check.h> #include <linux/memcontrol.h> #include <linux/ftrace.h> #include <linux/lockdep.h> -#include <linux/nmi.h> #include <linux/psi.h> - -#include <asm/sections.h> -#include <asm/tlbflush.h> +#include <linux/khugepaged.h> +#include <linux/delayacct.h> +#include <linux/cacheinfo.h> +#include <linux/pgalloc_tag.h> #include <asm/div64.h> #include "internal.h" +#include "shuffle.h" +#include "page_reporting.h" + +/* Free Page Internal flags: for internal, non-pcp variants of free_pages(). */ +typedef int __bitwise fpi_t; + +/* No special request */ +#define FPI_NONE ((__force fpi_t)0) + +/* + * Skip free page reporting notification for the (possibly merged) page. + * This does not hinder free page reporting from grabbing the page, + * reporting it and marking it "reported" - it only skips notifying + * the free page reporting infrastructure about a newly freed page. For + * example, used when temporarily pulling a page from a freelist and + * putting it back unmodified. + */ +#define FPI_SKIP_REPORT_NOTIFY ((__force fpi_t)BIT(0)) + +/* + * Place the (possibly merged) page to the tail of the freelist. Will ignore + * page shuffling (relevant code - e.g., memory onlining - is expected to + * shuffle the whole zone). + * + * Note: No code should rely on this flag for correctness - it's purely + * to allow for optimizations when handing back either fresh pages + * (memory onlining) or untouched pages (page isolation, free page + * reporting). + */ +#define FPI_TO_TAIL ((__force fpi_t)BIT(1)) + +/* Free the page without taking locks. Rely on trylock only. */ +#define FPI_TRYLOCK ((__force fpi_t)BIT(2)) /* prevent >1 _updater_ of zone percpu pageset ->high and ->batch fields */ static DEFINE_MUTEX(pcp_batch_high_lock); -#define MIN_PERCPU_PAGELIST_FRACTION (8) +#define MIN_PERCPU_PAGELIST_HIGH_FRACTION (8) + +#if defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT) +/* + * On SMP, spin_trylock is sufficient protection. + * On PREEMPT_RT, spin_trylock is equivalent on both SMP and UP. + * Pass flags to a no-op inline function to typecheck and silence the unused + * variable warning. + */ +static inline void __pcp_trylock_noop(unsigned long *flags) { } +#define pcp_trylock_prepare(flags) __pcp_trylock_noop(&(flags)) +#define pcp_trylock_finish(flags) __pcp_trylock_noop(&(flags)) +#else + +/* UP spin_trylock always succeeds so disable IRQs to prevent re-entrancy. */ +#define pcp_trylock_prepare(flags) local_irq_save(flags) +#define pcp_trylock_finish(flags) local_irq_restore(flags) +#endif + +/* + * Locking a pcp requires a PCP lookup followed by a spinlock. To avoid + * a migration causing the wrong PCP to be locked and remote memory being + * potentially allocated, pin the task to the CPU for the lookup+lock. + * preempt_disable is used on !RT because it is faster than migrate_disable. + * migrate_disable is used on RT because otherwise RT spinlock usage is + * interfered with and a high priority task cannot preempt the allocator. + */ +#ifndef CONFIG_PREEMPT_RT +#define pcpu_task_pin() preempt_disable() +#define pcpu_task_unpin() preempt_enable() +#else +#define pcpu_task_pin() migrate_disable() +#define pcpu_task_unpin() migrate_enable() +#endif + +/* + * Generic helper to lookup and a per-cpu variable with an embedded spinlock. + * Return value should be used with equivalent unlock helper. + */ +#define pcpu_spin_trylock(type, member, ptr) \ +({ \ + type *_ret; \ + pcpu_task_pin(); \ + _ret = this_cpu_ptr(ptr); \ + if (!spin_trylock(&_ret->member)) { \ + pcpu_task_unpin(); \ + _ret = NULL; \ + } \ + _ret; \ +}) + +#define pcpu_spin_unlock(member, ptr) \ +({ \ + spin_unlock(&ptr->member); \ + pcpu_task_unpin(); \ +}) + +/* struct per_cpu_pages specific helpers. */ +#define pcp_spin_trylock(ptr, UP_flags) \ +({ \ + struct per_cpu_pages *__ret; \ + pcp_trylock_prepare(UP_flags); \ + __ret = pcpu_spin_trylock(struct per_cpu_pages, lock, ptr); \ + if (!__ret) \ + pcp_trylock_finish(UP_flags); \ + __ret; \ +}) + +#define pcp_spin_unlock(ptr, UP_flags) \ +({ \ + pcpu_spin_unlock(lock, ptr); \ + pcp_trylock_finish(UP_flags); \ +}) #ifdef CONFIG_USE_PERCPU_NUMA_NODE_ID DEFINE_PER_CPU(int, numa_node); @@ -93,16 +183,9 @@ DEFINE_STATIC_KEY_TRUE(vm_numa_stat_key); */ DEFINE_PER_CPU(int, _numa_mem_); /* Kernel "local memory" node */ EXPORT_PER_CPU_SYMBOL(_numa_mem_); -int _node_numa_mem_[MAX_NUMNODES]; #endif -/* work_structs for global per-cpu drains */ -struct pcpu_drain { - struct zone *zone; - struct work_struct work; -}; -DEFINE_MUTEX(pcpu_drain_mutex); -DEFINE_PER_CPU(struct pcpu_drain, pcpu_drain); +static DEFINE_MUTEX(pcpu_drain_mutex); #ifdef CONFIG_GCC_PLUGIN_LATENT_ENTROPY volatile unsigned long latent_entropy __latent_entropy; @@ -126,75 +209,14 @@ nodemask_t node_states[NR_NODE_STATES] __read_mostly = { }; EXPORT_SYMBOL(node_states); -atomic_long_t _totalram_pages __read_mostly; -EXPORT_SYMBOL(_totalram_pages); -unsigned long totalreserve_pages __read_mostly; -unsigned long totalcma_pages __read_mostly; - -int percpu_pagelist_fraction; gfp_t gfp_allowed_mask __read_mostly = GFP_BOOT_MASK; -/* - * A cached value of the page's pageblock's migratetype, used when the page is - * put on a pcplist. Used to avoid the pageblock migratetype lookup when - * freeing from pcplists in most cases, at the cost of possibly becoming stale. - * Also the migratetype set in the page does not necessarily match the pcplist - * index, e.g. page might have MIGRATE_CMA set but be on a pcplist with any - * other index - this ensures that it will be put on the correct CMA freelist. - */ -static inline int get_pcppage_migratetype(struct page *page) -{ - return page->index; -} - -static inline void set_pcppage_migratetype(struct page *page, int migratetype) -{ - page->index = migratetype; -} - -#ifdef CONFIG_PM_SLEEP -/* - * The following functions are used by the suspend/hibernate code to temporarily - * change gfp_allowed_mask in order to avoid using I/O during memory allocations - * while devices are suspended. To avoid races with the suspend/hibernate code, - * they should always be called with system_transition_mutex held - * (gfp_allowed_mask also should only be modified with system_transition_mutex - * held, unless the suspend/hibernate code is guaranteed not to run in parallel - * with that modification). - */ - -static gfp_t saved_gfp_mask; - -void pm_restore_gfp_mask(void) -{ - WARN_ON(!mutex_is_locked(&system_transition_mutex)); - if (saved_gfp_mask) { - gfp_allowed_mask = saved_gfp_mask; - saved_gfp_mask = 0; - } -} - -void pm_restrict_gfp_mask(void) -{ - WARN_ON(!mutex_is_locked(&system_transition_mutex)); - WARN_ON(saved_gfp_mask); - saved_gfp_mask = gfp_allowed_mask; - gfp_allowed_mask &= ~(__GFP_IO | __GFP_FS); -} - -bool pm_suspended_storage(void) -{ - if ((gfp_allowed_mask & (__GFP_IO | __GFP_FS)) == (__GFP_IO | __GFP_FS)) - return false; - return true; -} -#endif /* CONFIG_PM_SLEEP */ - #ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE unsigned int pageblock_order __read_mostly; #endif -static void __free_pages_ok(struct page *page, unsigned int order); +static void __free_pages_ok(struct page *page, unsigned int order, + fpi_t fpi_flags); /* * results with 256, 32 in the lowmem_reserve sysctl: @@ -207,7 +229,7 @@ static void __free_pages_ok(struct page *page, unsigned int order); * TBD: should special case ZONE_DMA32 machines here - in those we normally * don't need any ZONE_NORMAL reservation */ -int sysctl_lowmem_reserve_ratio[MAX_NR_ZONES] = { +static int sysctl_lowmem_reserve_ratio[MAX_NR_ZONES] = { #ifdef CONFIG_ZONE_DMA [ZONE_DMA] = 256, #endif @@ -221,9 +243,7 @@ int sysctl_lowmem_reserve_ratio[MAX_NR_ZONES] = { [ZONE_MOVABLE] = 0, }; -EXPORT_SYMBOL(totalram_pages); - -static char * const zone_names[MAX_NR_ZONES] = { +char * const zone_names[MAX_NR_ZONES] = { #ifdef CONFIG_ZONE_DMA "DMA", #endif @@ -253,48 +273,28 @@ const char * const migratetype_names[MIGRATE_TYPES] = { #endif }; -compound_page_dtor * const compound_page_dtors[] = { - NULL, - free_compound_page, -#ifdef CONFIG_HUGETLB_PAGE - free_huge_page, -#endif -#ifdef CONFIG_TRANSPARENT_HUGEPAGE - free_transhuge_page, -#endif -}; - int min_free_kbytes = 1024; int user_min_free_kbytes = -1; -int watermark_boost_factor __read_mostly = 15000; -int watermark_scale_factor = 10; - -static unsigned long nr_kernel_pages __initdata; -static unsigned long nr_all_pages __initdata; -static unsigned long dma_reserve __initdata; - -#ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP -static unsigned long arch_zone_lowest_possible_pfn[MAX_NR_ZONES] __initdata; -static unsigned long arch_zone_highest_possible_pfn[MAX_NR_ZONES] __initdata; -static unsigned long required_kernelcore __initdata; -static unsigned long required_kernelcore_percent __initdata; -static unsigned long required_movablecore __initdata; -static unsigned long required_movablecore_percent __initdata; -static unsigned long zone_movable_pfn[MAX_NUMNODES] __initdata; -static bool mirrored_kernelcore __meminitdata; +static int watermark_boost_factor __read_mostly = 15000; +static int watermark_scale_factor = 10; +int defrag_mode; /* movable_zone is the "real" zone pages in ZONE_MOVABLE are taken from */ int movable_zone; EXPORT_SYMBOL(movable_zone); -#endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */ #if MAX_NUMNODES > 1 -int nr_node_ids __read_mostly = MAX_NUMNODES; -int nr_online_nodes __read_mostly = 1; +unsigned int nr_node_ids __read_mostly = MAX_NUMNODES; +unsigned int nr_online_nodes __read_mostly = 1; EXPORT_SYMBOL(nr_node_ids); EXPORT_SYMBOL(nr_online_nodes); #endif +static bool page_contains_unaccepted(struct page *page, unsigned int order); +static bool cond_accept_memory(struct zone *zone, unsigned int order, + int alloc_flags); +static bool __free_unaccepted(struct page *page); + int page_group_by_mobility_disabled __read_mostly; #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT @@ -303,202 +303,281 @@ int page_group_by_mobility_disabled __read_mostly; * page_alloc_init_late() has finished, the deferred pages are all initialized, * and we can permanently disable that path. */ -static DEFINE_STATIC_KEY_TRUE(deferred_pages); +DEFINE_STATIC_KEY_TRUE(deferred_pages); -/* - * Calling kasan_free_pages() only after deferred memory initialization - * has completed. Poisoning pages during deferred memory init will greatly - * lengthen the process and cause problem in large memory systems as the - * deferred pages initialization is done with interrupt disabled. - * - * Assuming that there will be no reference to those newly initialized - * pages before they are ever allocated, this should have no effect on - * KASAN memory tracking as the poison will be properly inserted at page - * allocation time. The only corner case is when pages are allocated by - * on-demand allocation and then freed again before the deferred pages - * initialization is done, but this is not likely to happen. - */ -static inline void kasan_free_nondeferred_pages(struct page *page, int order) +static inline bool deferred_pages_enabled(void) { - if (!static_branch_unlikely(&deferred_pages)) - kasan_free_pages(page, order); -} - -/* Returns true if the struct page for the pfn is uninitialised */ -static inline bool __meminit early_page_uninitialised(unsigned long pfn) -{ - int nid = early_pfn_to_nid(pfn); - - if (node_online(nid) && pfn >= NODE_DATA(nid)->first_deferred_pfn) - return true; - - return false; + return static_branch_unlikely(&deferred_pages); } /* - * Returns true when the remaining initialisation should be deferred until - * later in the boot cycle when it can be parallelised. + * deferred_grow_zone() is __init, but it is called from + * get_page_from_freelist() during early boot until deferred_pages permanently + * disables this call. This is why we have refdata wrapper to avoid warning, + * and to ensure that the function body gets unloaded. */ -static bool __meminit -defer_init(int nid, unsigned long pfn, unsigned long end_pfn) +static bool __ref +_deferred_grow_zone(struct zone *zone, unsigned int order) { - static unsigned long prev_end_pfn, nr_initialised; - - /* - * prev_end_pfn static that contains the end of previous zone - * No need to protect because called very early in boot before smp_init. - */ - if (prev_end_pfn != end_pfn) { - prev_end_pfn = end_pfn; - nr_initialised = 0; - } - - /* Always populate low zones for address-constrained allocations */ - if (end_pfn < pgdat_end_pfn(NODE_DATA(nid))) - return false; - - /* - * We start only with one section of pages, more pages are added as - * needed until the rest of deferred pages are initialized. - */ - nr_initialised++; - if ((nr_initialised > PAGES_PER_SECTION) && - (pfn & (PAGES_PER_SECTION - 1)) == 0) { - NODE_DATA(nid)->first_deferred_pfn = pfn; - return true; - } - return false; + return deferred_grow_zone(zone, order); } #else -#define kasan_free_nondeferred_pages(p, o) kasan_free_pages(p, o) - -static inline bool early_page_uninitialised(unsigned long pfn) +static inline bool deferred_pages_enabled(void) { return false; } -static inline bool defer_init(int nid, unsigned long pfn, unsigned long end_pfn) +static inline bool _deferred_grow_zone(struct zone *zone, unsigned int order) { return false; } -#endif +#endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */ /* Return a pointer to the bitmap storing bits affecting a block of pages */ -static inline unsigned long *get_pageblock_bitmap(struct page *page, +static inline unsigned long *get_pageblock_bitmap(const struct page *page, unsigned long pfn) { #ifdef CONFIG_SPARSEMEM - return __pfn_to_section(pfn)->pageblock_flags; + return section_to_usemap(__pfn_to_section(pfn)); #else return page_zone(page)->pageblock_flags; #endif /* CONFIG_SPARSEMEM */ } -static inline int pfn_to_bitidx(struct page *page, unsigned long pfn) +static inline int pfn_to_bitidx(const struct page *page, unsigned long pfn) { #ifdef CONFIG_SPARSEMEM pfn &= (PAGES_PER_SECTION-1); - return (pfn >> pageblock_order) * NR_PAGEBLOCK_BITS; #else - pfn = pfn - round_down(page_zone(page)->zone_start_pfn, pageblock_nr_pages); - return (pfn >> pageblock_order) * NR_PAGEBLOCK_BITS; + pfn = pfn - pageblock_start_pfn(page_zone(page)->zone_start_pfn); #endif /* CONFIG_SPARSEMEM */ + return (pfn >> pageblock_order) * NR_PAGEBLOCK_BITS; } +static __always_inline bool is_standalone_pb_bit(enum pageblock_bits pb_bit) +{ + return pb_bit >= PB_compact_skip && pb_bit < __NR_PAGEBLOCK_BITS; +} + +static __always_inline void +get_pfnblock_bitmap_bitidx(const struct page *page, unsigned long pfn, + unsigned long **bitmap_word, unsigned long *bitidx) +{ + unsigned long *bitmap; + unsigned long word_bitidx; + +#ifdef CONFIG_MEMORY_ISOLATION + BUILD_BUG_ON(NR_PAGEBLOCK_BITS != 8); +#else + BUILD_BUG_ON(NR_PAGEBLOCK_BITS != 4); +#endif + BUILD_BUG_ON(__MIGRATE_TYPE_END > MIGRATETYPE_MASK); + VM_BUG_ON_PAGE(!zone_spans_pfn(page_zone(page), pfn), page); + + bitmap = get_pageblock_bitmap(page, pfn); + *bitidx = pfn_to_bitidx(page, pfn); + word_bitidx = *bitidx / BITS_PER_LONG; + *bitidx &= (BITS_PER_LONG - 1); + *bitmap_word = &bitmap[word_bitidx]; +} + + /** - * get_pfnblock_flags_mask - Return the requested group of flags for the pageblock_nr_pages block of pages + * __get_pfnblock_flags_mask - Return the requested group of flags for + * a pageblock_nr_pages block of pages * @page: The page within the block of interest * @pfn: The target page frame number - * @end_bitidx: The last bit of interest to retrieve * @mask: mask of bits that the caller is interested in * * Return: pageblock_bits flags */ -static __always_inline unsigned long __get_pfnblock_flags_mask(struct page *page, - unsigned long pfn, - unsigned long end_bitidx, - unsigned long mask) +static unsigned long __get_pfnblock_flags_mask(const struct page *page, + unsigned long pfn, + unsigned long mask) { - unsigned long *bitmap; - unsigned long bitidx, word_bitidx; + unsigned long *bitmap_word; + unsigned long bitidx; unsigned long word; - bitmap = get_pageblock_bitmap(page, pfn); - bitidx = pfn_to_bitidx(page, pfn); - word_bitidx = bitidx / BITS_PER_LONG; - bitidx &= (BITS_PER_LONG-1); - - word = bitmap[word_bitidx]; - bitidx += end_bitidx; - return (word >> (BITS_PER_LONG - bitidx - 1)) & mask; + get_pfnblock_bitmap_bitidx(page, pfn, &bitmap_word, &bitidx); + /* + * This races, without locks, with set_pfnblock_migratetype(). Ensure + * a consistent read of the memory array, so that results, even though + * racy, are not corrupted. + */ + word = READ_ONCE(*bitmap_word); + return (word >> bitidx) & mask; } -unsigned long get_pfnblock_flags_mask(struct page *page, unsigned long pfn, - unsigned long end_bitidx, - unsigned long mask) +/** + * get_pfnblock_bit - Check if a standalone bit of a pageblock is set + * @page: The page within the block of interest + * @pfn: The target page frame number + * @pb_bit: pageblock bit to check + * + * Return: true if the bit is set, otherwise false + */ +bool get_pfnblock_bit(const struct page *page, unsigned long pfn, + enum pageblock_bits pb_bit) { - return __get_pfnblock_flags_mask(page, pfn, end_bitidx, mask); + unsigned long *bitmap_word; + unsigned long bitidx; + + if (WARN_ON_ONCE(!is_standalone_pb_bit(pb_bit))) + return false; + + get_pfnblock_bitmap_bitidx(page, pfn, &bitmap_word, &bitidx); + + return test_bit(bitidx + pb_bit, bitmap_word); } -static __always_inline int get_pfnblock_migratetype(struct page *page, unsigned long pfn) +/** + * get_pfnblock_migratetype - Return the migratetype of a pageblock + * @page: The page within the block of interest + * @pfn: The target page frame number + * + * Return: The migratetype of the pageblock + * + * Use get_pfnblock_migratetype() if caller already has both @page and @pfn + * to save a call to page_to_pfn(). + */ +__always_inline enum migratetype +get_pfnblock_migratetype(const struct page *page, unsigned long pfn) { - return __get_pfnblock_flags_mask(page, pfn, PB_migrate_end, MIGRATETYPE_MASK); + unsigned long mask = MIGRATETYPE_AND_ISO_MASK; + unsigned long flags; + + flags = __get_pfnblock_flags_mask(page, pfn, mask); + +#ifdef CONFIG_MEMORY_ISOLATION + if (flags & BIT(PB_migrate_isolate)) + return MIGRATE_ISOLATE; +#endif + return flags & MIGRATETYPE_MASK; } /** - * set_pfnblock_flags_mask - Set the requested group of flags for a pageblock_nr_pages block of pages + * __set_pfnblock_flags_mask - Set the requested group of flags for + * a pageblock_nr_pages block of pages * @page: The page within the block of interest - * @flags: The flags to set * @pfn: The target page frame number - * @end_bitidx: The last bit of interest + * @flags: The flags to set * @mask: mask of bits that the caller is interested in */ -void set_pfnblock_flags_mask(struct page *page, unsigned long flags, - unsigned long pfn, - unsigned long end_bitidx, - unsigned long mask) +static void __set_pfnblock_flags_mask(struct page *page, unsigned long pfn, + unsigned long flags, unsigned long mask) { - unsigned long *bitmap; - unsigned long bitidx, word_bitidx; - unsigned long old_word, word; + unsigned long *bitmap_word; + unsigned long bitidx; + unsigned long word; - BUILD_BUG_ON(NR_PAGEBLOCK_BITS != 4); - BUILD_BUG_ON(MIGRATE_TYPES > (1 << PB_migratetype_bits)); + get_pfnblock_bitmap_bitidx(page, pfn, &bitmap_word, &bitidx); - bitmap = get_pageblock_bitmap(page, pfn); - bitidx = pfn_to_bitidx(page, pfn); - word_bitidx = bitidx / BITS_PER_LONG; - bitidx &= (BITS_PER_LONG-1); + mask <<= bitidx; + flags <<= bitidx; - VM_BUG_ON_PAGE(!zone_spans_pfn(page_zone(page), pfn), page); + word = READ_ONCE(*bitmap_word); + do { + } while (!try_cmpxchg(bitmap_word, &word, (word & ~mask) | flags)); +} - bitidx += end_bitidx; - mask <<= (BITS_PER_LONG - bitidx - 1); - flags <<= (BITS_PER_LONG - bitidx - 1); +/** + * set_pfnblock_bit - Set a standalone bit of a pageblock + * @page: The page within the block of interest + * @pfn: The target page frame number + * @pb_bit: pageblock bit to set + */ +void set_pfnblock_bit(const struct page *page, unsigned long pfn, + enum pageblock_bits pb_bit) +{ + unsigned long *bitmap_word; + unsigned long bitidx; - word = READ_ONCE(bitmap[word_bitidx]); - for (;;) { - old_word = cmpxchg(&bitmap[word_bitidx], word, (word & ~mask) | flags); - if (word == old_word) - break; - word = old_word; + if (WARN_ON_ONCE(!is_standalone_pb_bit(pb_bit))) + return; + + get_pfnblock_bitmap_bitidx(page, pfn, &bitmap_word, &bitidx); + + set_bit(bitidx + pb_bit, bitmap_word); +} + +/** + * clear_pfnblock_bit - Clear a standalone bit of a pageblock + * @page: The page within the block of interest + * @pfn: The target page frame number + * @pb_bit: pageblock bit to clear + */ +void clear_pfnblock_bit(const struct page *page, unsigned long pfn, + enum pageblock_bits pb_bit) +{ + unsigned long *bitmap_word; + unsigned long bitidx; + + if (WARN_ON_ONCE(!is_standalone_pb_bit(pb_bit))) + return; + + get_pfnblock_bitmap_bitidx(page, pfn, &bitmap_word, &bitidx); + + clear_bit(bitidx + pb_bit, bitmap_word); +} + +/** + * set_pageblock_migratetype - Set the migratetype of a pageblock + * @page: The page within the block of interest + * @migratetype: migratetype to set + */ +static void set_pageblock_migratetype(struct page *page, + enum migratetype migratetype) +{ + if (unlikely(page_group_by_mobility_disabled && + migratetype < MIGRATE_PCPTYPES)) + migratetype = MIGRATE_UNMOVABLE; + +#ifdef CONFIG_MEMORY_ISOLATION + if (migratetype == MIGRATE_ISOLATE) { + VM_WARN_ONCE(1, + "Use set_pageblock_isolate() for pageblock isolation"); + return; } + VM_WARN_ONCE(get_pageblock_isolate(page), + "Use clear_pageblock_isolate() to unisolate pageblock"); + /* MIGRATETYPE_AND_ISO_MASK clears PB_migrate_isolate if it is set */ +#endif + __set_pfnblock_flags_mask(page, page_to_pfn(page), + (unsigned long)migratetype, + MIGRATETYPE_AND_ISO_MASK); } -void set_pageblock_migratetype(struct page *page, int migratetype) +void __meminit init_pageblock_migratetype(struct page *page, + enum migratetype migratetype, + bool isolate) { + unsigned long flags; + if (unlikely(page_group_by_mobility_disabled && migratetype < MIGRATE_PCPTYPES)) migratetype = MIGRATE_UNMOVABLE; - set_pageblock_flags_group(page, (unsigned long)migratetype, - PB_migrate, PB_migrate_end); + flags = migratetype; + +#ifdef CONFIG_MEMORY_ISOLATION + if (migratetype == MIGRATE_ISOLATE) { + VM_WARN_ONCE( + 1, + "Set isolate=true to isolate pageblock with a migratetype"); + return; + } + if (isolate) + flags |= BIT(PB_migrate_isolate); +#endif + __set_pfnblock_flags_mask(page, page_to_pfn(page), flags, + MIGRATETYPE_AND_ISO_MASK); } #ifdef CONFIG_DEBUG_VM static int page_outside_zone_boundaries(struct zone *zone, struct page *page) { - int ret = 0; + int ret; unsigned seq; unsigned long pfn = page_to_pfn(page); unsigned long sp, start_pfn; @@ -507,8 +586,7 @@ static int page_outside_zone_boundaries(struct zone *zone, struct page *page) seq = zone_span_seqbegin(zone); start_pfn = zone->zone_start_pfn; sp = zone->spanned_pages; - if (!zone_spans_pfn(zone, pfn)) - ret = 1; + ret = !zone_spans_pfn(zone, pfn); } while (zone_span_seqretry(zone, seq)); if (ret) @@ -519,36 +597,26 @@ static int page_outside_zone_boundaries(struct zone *zone, struct page *page) return ret; } -static int page_is_consistent(struct zone *zone, struct page *page) -{ - if (!pfn_valid_within(page_to_pfn(page))) - return 0; - if (zone != page_zone(page)) - return 0; - - return 1; -} /* * Temporary debugging check for pages not lying within a given zone. */ -static int __maybe_unused bad_range(struct zone *zone, struct page *page) +static bool __maybe_unused bad_range(struct zone *zone, struct page *page) { if (page_outside_zone_boundaries(zone, page)) - return 1; - if (!page_is_consistent(zone, page)) - return 1; + return true; + if (zone != page_zone(page)) + return true; - return 0; + return false; } #else -static inline int __maybe_unused bad_range(struct zone *zone, struct page *page) +static inline bool __maybe_unused bad_range(struct zone *zone, struct page *page) { - return 0; + return false; } #endif -static void bad_page(struct page *page, const char *reason, - unsigned long bad_flags) +static void bad_page(struct page *page, const char *reason) { static unsigned long resume; static unsigned long nr_shown; @@ -576,21 +644,61 @@ static void bad_page(struct page *page, const char *reason, pr_alert("BUG: Bad page state in process %s pfn:%05lx\n", current->comm, page_to_pfn(page)); - __dump_page(page, reason); - bad_flags &= page->flags; - if (bad_flags) - pr_alert("bad because of flags: %#lx(%pGp)\n", - bad_flags, &bad_flags); - dump_page_owner(page); + dump_page(page, reason); print_modules(); dump_stack(); out: /* Leave bad fields for debug, except PageBuddy could make trouble */ - page_mapcount_reset(page); /* remove PageBuddy */ + if (PageBuddy(page)) + __ClearPageBuddy(page); add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE); } +static inline unsigned int order_to_pindex(int migratetype, int order) +{ + +#ifdef CONFIG_TRANSPARENT_HUGEPAGE + bool movable; + if (order > PAGE_ALLOC_COSTLY_ORDER) { + VM_BUG_ON(order != HPAGE_PMD_ORDER); + + movable = migratetype == MIGRATE_MOVABLE; + + return NR_LOWORDER_PCP_LISTS + movable; + } +#else + VM_BUG_ON(order > PAGE_ALLOC_COSTLY_ORDER); +#endif + + return (MIGRATE_PCPTYPES * order) + migratetype; +} + +static inline int pindex_to_order(unsigned int pindex) +{ + int order = pindex / MIGRATE_PCPTYPES; + +#ifdef CONFIG_TRANSPARENT_HUGEPAGE + if (pindex >= NR_LOWORDER_PCP_LISTS) + order = HPAGE_PMD_ORDER; +#else + VM_BUG_ON(order > PAGE_ALLOC_COSTLY_ORDER); +#endif + + return order; +} + +static inline bool pcp_allowed_order(unsigned int order) +{ + if (order <= PAGE_ALLOC_COSTLY_ORDER) + return true; +#ifdef CONFIG_TRANSPARENT_HUGEPAGE + if (order == HPAGE_PMD_ORDER) + return true; +#endif + return false; +} + /* * Higher-order pages are called "compound pages". They are structured thusly: * @@ -599,194 +707,211 @@ out: * The remaining PAGE_SIZE pages are called "tail pages". PageTail() is encoded * in bit 0 of page->compound_head. The rest of bits is pointer to head page. * - * The first tail page's ->compound_dtor holds the offset in array of compound - * page destructors. See compound_page_dtors. - * * The first tail page's ->compound_order holds the order of allocation. * This usage means that zero-order pages may not be compound. */ -void free_compound_page(struct page *page) -{ - __free_pages_ok(page, compound_order(page)); -} - void prep_compound_page(struct page *page, unsigned int order) { int i; int nr_pages = 1 << order; - set_compound_page_dtor(page, COMPOUND_PAGE_DTOR); - set_compound_order(page, order); __SetPageHead(page); - for (i = 1; i < nr_pages; i++) { - struct page *p = page + i; - set_page_count(p, 0); - p->mapping = TAIL_MAPPING; - set_compound_head(p, page); - } - atomic_set(compound_mapcount_ptr(page), -1); + for (i = 1; i < nr_pages; i++) + prep_compound_tail(page, i); + + prep_compound_head(page, order); } -#ifdef CONFIG_DEBUG_PAGEALLOC -unsigned int _debug_guardpage_minorder; -bool _debug_pagealloc_enabled __read_mostly - = IS_ENABLED(CONFIG_DEBUG_PAGEALLOC_ENABLE_DEFAULT); -EXPORT_SYMBOL(_debug_pagealloc_enabled); -bool _debug_guardpage_enabled __read_mostly; +static inline void set_buddy_order(struct page *page, unsigned int order) +{ + set_page_private(page, order); + __SetPageBuddy(page); +} -static int __init early_debug_pagealloc(char *buf) +#ifdef CONFIG_COMPACTION +static inline struct capture_control *task_capc(struct zone *zone) { - if (!buf) - return -EINVAL; - return kstrtobool(buf, &_debug_pagealloc_enabled); + struct capture_control *capc = current->capture_control; + + return unlikely(capc) && + !(current->flags & PF_KTHREAD) && + !capc->page && + capc->cc->zone == zone ? capc : NULL; } -early_param("debug_pagealloc", early_debug_pagealloc); -static bool need_debug_guardpage(void) +static inline bool +compaction_capture(struct capture_control *capc, struct page *page, + int order, int migratetype) { - /* If we don't use debug_pagealloc, we don't need guard page */ - if (!debug_pagealloc_enabled()) + if (!capc || order != capc->cc->order) return false; - if (!debug_guardpage_minorder()) + /* Do not accidentally pollute CMA or isolated regions*/ + if (is_migrate_cma(migratetype) || + is_migrate_isolate(migratetype)) return false; + /* + * Do not let lower order allocations pollute a movable pageblock + * unless compaction is also requesting movable pages. + * This might let an unmovable request use a reclaimable pageblock + * and vice-versa but no more than normal fallback logic which can + * have trouble finding a high-order free page. + */ + if (order < pageblock_order && migratetype == MIGRATE_MOVABLE && + capc->cc->migratetype != MIGRATE_MOVABLE) + return false; + + if (migratetype != capc->cc->migratetype) + trace_mm_page_alloc_extfrag(page, capc->cc->order, order, + capc->cc->migratetype, migratetype); + + capc->page = page; return true; } -static void init_debug_guardpage(void) +#else +static inline struct capture_control *task_capc(struct zone *zone) { - if (!debug_pagealloc_enabled()) - return; - - if (!debug_guardpage_minorder()) - return; - - _debug_guardpage_enabled = true; + return NULL; } -struct page_ext_operations debug_guardpage_ops = { - .need = need_debug_guardpage, - .init = init_debug_guardpage, -}; +static inline bool +compaction_capture(struct capture_control *capc, struct page *page, + int order, int migratetype) +{ + return false; +} +#endif /* CONFIG_COMPACTION */ -static int __init debug_guardpage_minorder_setup(char *buf) +static inline void account_freepages(struct zone *zone, int nr_pages, + int migratetype) { - unsigned long res; + lockdep_assert_held(&zone->lock); - if (kstrtoul(buf, 10, &res) < 0 || res > MAX_ORDER / 2) { - pr_err("Bad debug_guardpage_minorder value\n"); - return 0; - } - _debug_guardpage_minorder = res; - pr_info("Setting debug_guardpage_minorder to %lu\n", res); - return 0; + if (is_migrate_isolate(migratetype)) + return; + + __mod_zone_page_state(zone, NR_FREE_PAGES, nr_pages); + + if (is_migrate_cma(migratetype)) + __mod_zone_page_state(zone, NR_FREE_CMA_PAGES, nr_pages); + else if (migratetype == MIGRATE_HIGHATOMIC) + WRITE_ONCE(zone->nr_free_highatomic, + zone->nr_free_highatomic + nr_pages); } -early_param("debug_guardpage_minorder", debug_guardpage_minorder_setup); -static inline bool set_page_guard(struct zone *zone, struct page *page, - unsigned int order, int migratetype) +/* Used for pages not on another list */ +static inline void __add_to_free_list(struct page *page, struct zone *zone, + unsigned int order, int migratetype, + bool tail) { - struct page_ext *page_ext; + struct free_area *area = &zone->free_area[order]; + int nr_pages = 1 << order; - if (!debug_guardpage_enabled()) - return false; + VM_WARN_ONCE(get_pageblock_migratetype(page) != migratetype, + "page type is %d, passed migratetype is %d (nr=%d)\n", + get_pageblock_migratetype(page), migratetype, nr_pages); - if (order >= debug_guardpage_minorder()) - return false; + if (tail) + list_add_tail(&page->buddy_list, &area->free_list[migratetype]); + else + list_add(&page->buddy_list, &area->free_list[migratetype]); + area->nr_free++; - page_ext = lookup_page_ext(page); - if (unlikely(!page_ext)) - return false; + if (order >= pageblock_order && !is_migrate_isolate(migratetype)) + __mod_zone_page_state(zone, NR_FREE_PAGES_BLOCKS, nr_pages); +} + +/* + * Used for pages which are on another list. Move the pages to the tail + * of the list - so the moved pages won't immediately be considered for + * allocation again (e.g., optimization for memory onlining). + */ +static inline void move_to_free_list(struct page *page, struct zone *zone, + unsigned int order, int old_mt, int new_mt) +{ + struct free_area *area = &zone->free_area[order]; + int nr_pages = 1 << order; - __set_bit(PAGE_EXT_DEBUG_GUARD, &page_ext->flags); + /* Free page moving can fail, so it happens before the type update */ + VM_WARN_ONCE(get_pageblock_migratetype(page) != old_mt, + "page type is %d, passed migratetype is %d (nr=%d)\n", + get_pageblock_migratetype(page), old_mt, nr_pages); - INIT_LIST_HEAD(&page->lru); - set_page_private(page, order); - /* Guard pages are not available for any usage */ - __mod_zone_freepage_state(zone, -(1 << order), migratetype); + list_move_tail(&page->buddy_list, &area->free_list[new_mt]); - return true; + account_freepages(zone, -nr_pages, old_mt); + account_freepages(zone, nr_pages, new_mt); + + if (order >= pageblock_order && + is_migrate_isolate(old_mt) != is_migrate_isolate(new_mt)) { + if (!is_migrate_isolate(old_mt)) + nr_pages = -nr_pages; + __mod_zone_page_state(zone, NR_FREE_PAGES_BLOCKS, nr_pages); + } } -static inline void clear_page_guard(struct zone *zone, struct page *page, - unsigned int order, int migratetype) +static inline void __del_page_from_free_list(struct page *page, struct zone *zone, + unsigned int order, int migratetype) { - struct page_ext *page_ext; - - if (!debug_guardpage_enabled()) - return; + int nr_pages = 1 << order; - page_ext = lookup_page_ext(page); - if (unlikely(!page_ext)) - return; + VM_WARN_ONCE(get_pageblock_migratetype(page) != migratetype, + "page type is %d, passed migratetype is %d (nr=%d)\n", + get_pageblock_migratetype(page), migratetype, nr_pages); - __clear_bit(PAGE_EXT_DEBUG_GUARD, &page_ext->flags); + /* clear reported state and update reported page count */ + if (page_reported(page)) + __ClearPageReported(page); + list_del(&page->buddy_list); + __ClearPageBuddy(page); set_page_private(page, 0); - if (!is_migrate_isolate(migratetype)) - __mod_zone_freepage_state(zone, (1 << order), migratetype); + zone->free_area[order].nr_free--; + + if (order >= pageblock_order && !is_migrate_isolate(migratetype)) + __mod_zone_page_state(zone, NR_FREE_PAGES_BLOCKS, -nr_pages); } -#else -struct page_ext_operations debug_guardpage_ops; -static inline bool set_page_guard(struct zone *zone, struct page *page, - unsigned int order, int migratetype) { return false; } -static inline void clear_page_guard(struct zone *zone, struct page *page, - unsigned int order, int migratetype) {} -#endif -static inline void set_page_order(struct page *page, unsigned int order) +static inline void del_page_from_free_list(struct page *page, struct zone *zone, + unsigned int order, int migratetype) { - set_page_private(page, order); - __SetPageBuddy(page); + __del_page_from_free_list(page, zone, order, migratetype); + account_freepages(zone, -(1 << order), migratetype); } -static inline void rmv_page_order(struct page *page) +static inline struct page *get_page_from_free_area(struct free_area *area, + int migratetype) { - __ClearPageBuddy(page); - set_page_private(page, 0); + return list_first_entry_or_null(&area->free_list[migratetype], + struct page, buddy_list); } /* - * This function checks whether a page is free && is the buddy - * we can coalesce a page and its buddy if - * (a) the buddy is not in a hole (check before calling!) && - * (b) the buddy is in the buddy system && - * (c) a page and its buddy have the same order && - * (d) a page and its buddy are in the same zone. - * - * For recording whether a page is in the buddy system, we set PageBuddy. - * Setting, clearing, and testing PageBuddy is serialized by zone->lock. - * - * For recording page's order, we use page_private(page). + * If this is less than the 2nd largest possible page, check if the buddy + * of the next-higher order is free. If it is, it's possible + * that pages are being freed that will coalesce soon. In case, + * that is happening, add the free page to the tail of the list + * so it's less likely to be used soon and more likely to be merged + * as a 2-level higher order page */ -static inline int page_is_buddy(struct page *page, struct page *buddy, - unsigned int order) +static inline bool +buddy_merge_likely(unsigned long pfn, unsigned long buddy_pfn, + struct page *page, unsigned int order) { - if (page_is_guard(buddy) && page_order(buddy) == order) { - if (page_zone_id(page) != page_zone_id(buddy)) - return 0; + unsigned long higher_page_pfn; + struct page *higher_page; - VM_BUG_ON_PAGE(page_count(buddy) != 0, buddy); - - return 1; - } - - if (PageBuddy(buddy) && page_order(buddy) == order) { - /* - * zone check is done late to avoid uselessly - * calculating zone/node ids for pages that could - * never merge. - */ - if (page_zone_id(page) != page_zone_id(buddy)) - return 0; + if (order >= MAX_PAGE_ORDER - 1) + return false; - VM_BUG_ON_PAGE(page_count(buddy) != 0, buddy); + higher_page_pfn = buddy_pfn & pfn; + higher_page = page + (higher_page_pfn - pfn); - return 1; - } - return 0; + return find_buddy_page_pfn(higher_page, higher_page_pfn, order + 1, + NULL) != NULL; } /* @@ -816,103 +941,89 @@ static inline int page_is_buddy(struct page *page, struct page *buddy, static inline void __free_one_page(struct page *page, unsigned long pfn, struct zone *zone, unsigned int order, - int migratetype) + int migratetype, fpi_t fpi_flags) { + struct capture_control *capc = task_capc(zone); + unsigned long buddy_pfn = 0; unsigned long combined_pfn; - unsigned long uninitialized_var(buddy_pfn); struct page *buddy; - unsigned int max_order; - - max_order = min_t(unsigned int, MAX_ORDER, pageblock_order + 1); + bool to_tail; VM_BUG_ON(!zone_is_initialized(zone)); - VM_BUG_ON_PAGE(page->flags & PAGE_FLAGS_CHECK_AT_PREP, page); + VM_BUG_ON_PAGE(page->flags.f & PAGE_FLAGS_CHECK_AT_PREP, page); VM_BUG_ON(migratetype == -1); - if (likely(!is_migrate_isolate(migratetype))) - __mod_zone_freepage_state(zone, 1 << order, migratetype); - VM_BUG_ON_PAGE(pfn & ((1 << order) - 1), page); VM_BUG_ON_PAGE(bad_range(zone, page), page); -continue_merging: - while (order < max_order - 1) { - buddy_pfn = __find_buddy_pfn(pfn, order); - buddy = page + (buddy_pfn - pfn); + account_freepages(zone, 1 << order, migratetype); - if (!pfn_valid_within(buddy_pfn)) - goto done_merging; - if (!page_is_buddy(page, buddy, order)) + while (order < MAX_PAGE_ORDER) { + int buddy_mt = migratetype; + + if (compaction_capture(capc, page, order, migratetype)) { + account_freepages(zone, -(1 << order), migratetype); + return; + } + + buddy = find_buddy_page_pfn(page, pfn, order, &buddy_pfn); + if (!buddy) goto done_merging; + + if (unlikely(order >= pageblock_order)) { + /* + * We want to prevent merge between freepages on pageblock + * without fallbacks and normal pageblock. Without this, + * pageblock isolation could cause incorrect freepage or CMA + * accounting or HIGHATOMIC accounting. + */ + buddy_mt = get_pfnblock_migratetype(buddy, buddy_pfn); + + if (migratetype != buddy_mt && + (!migratetype_is_mergeable(migratetype) || + !migratetype_is_mergeable(buddy_mt))) + goto done_merging; + } + /* * Our buddy is free or it is CONFIG_DEBUG_PAGEALLOC guard page, * merge with it and move up one order. */ - if (page_is_guard(buddy)) { - clear_page_guard(zone, buddy, order, migratetype); - } else { - list_del(&buddy->lru); - zone->free_area[order].nr_free--; - rmv_page_order(buddy); + if (page_is_guard(buddy)) + clear_page_guard(zone, buddy, order); + else + __del_page_from_free_list(buddy, zone, order, buddy_mt); + + if (unlikely(buddy_mt != migratetype)) { + /* + * Match buddy type. This ensures that an + * expand() down the line puts the sub-blocks + * on the right freelists. + */ + set_pageblock_migratetype(buddy, migratetype); } + combined_pfn = buddy_pfn & pfn; page = page + (combined_pfn - pfn); pfn = combined_pfn; order++; } - if (max_order < MAX_ORDER) { - /* If we are here, it means order is >= pageblock_order. - * We want to prevent merge between freepages on isolate - * pageblock and normal pageblock. Without this, pageblock - * isolation could cause incorrect freepage or CMA accounting. - * - * We don't want to hit this code for the more frequent - * low-order merging. - */ - if (unlikely(has_isolate_pageblock(zone))) { - int buddy_mt; - - buddy_pfn = __find_buddy_pfn(pfn, order); - buddy = page + (buddy_pfn - pfn); - buddy_mt = get_pageblock_migratetype(buddy); - - if (migratetype != buddy_mt - && (is_migrate_isolate(migratetype) || - is_migrate_isolate(buddy_mt))) - goto done_merging; - } - max_order++; - goto continue_merging; - } done_merging: - set_page_order(page, order); + set_buddy_order(page, order); - /* - * If this is not the largest possible page, check if the buddy - * of the next-highest order is free. If it is, it's possible - * that pages are being freed that will coalesce soon. In case, - * that is happening, add the free page to the tail of the list - * so it's less likely to be used soon and more likely to be merged - * as a higher order page - */ - if ((order < MAX_ORDER-2) && pfn_valid_within(buddy_pfn)) { - struct page *higher_page, *higher_buddy; - combined_pfn = buddy_pfn & pfn; - higher_page = page + (combined_pfn - pfn); - buddy_pfn = __find_buddy_pfn(combined_pfn, order + 1); - higher_buddy = higher_page + (buddy_pfn - combined_pfn); - if (pfn_valid_within(buddy_pfn) && - page_is_buddy(higher_page, higher_buddy, order + 1)) { - list_add_tail(&page->lru, - &zone->free_area[order].free_list[migratetype]); - goto out; - } - } + if (fpi_flags & FPI_TO_TAIL) + to_tail = true; + else if (is_shuffle_order(order)) + to_tail = shuffle_pick_tail(); + else + to_tail = buddy_merge_likely(pfn, buddy_pfn, page, order); - list_add(&page->lru, &zone->free_area[order].free_list[migratetype]); -out: - zone->free_area[order].nr_free++; + __add_to_free_list(page, zone, order, migratetype, to_tail); + + /* Notify page reporting subsystem of freed page */ + if (!(fpi_flags & FPI_SKIP_REPORT_NOTIFY)) + page_reporting_notify_free(order); } /* @@ -929,21 +1040,18 @@ static inline bool page_expected_state(struct page *page, if (unlikely((unsigned long)page->mapping | page_ref_count(page) | #ifdef CONFIG_MEMCG - (unsigned long)page->mem_cgroup | + page->memcg_data | #endif - (page->flags & check_flags))) + page_pool_page_is_pp(page) | + (page->flags.f & check_flags))) return false; return true; } -static void free_pages_check_bad(struct page *page) +static const char *page_bad_reason(struct page *page, unsigned long flags) { - const char *bad_reason; - unsigned long bad_flags; - - bad_reason = NULL; - bad_flags = 0; + const char *bad_reason = NULL; if (unlikely(atomic_read(&page->_mapcount) != -1)) bad_reason = "nonzero mapcount"; @@ -951,29 +1059,39 @@ static void free_pages_check_bad(struct page *page) bad_reason = "non-NULL mapping"; if (unlikely(page_ref_count(page) != 0)) bad_reason = "nonzero _refcount"; - if (unlikely(page->flags & PAGE_FLAGS_CHECK_AT_FREE)) { - bad_reason = "PAGE_FLAGS_CHECK_AT_FREE flag(s) set"; - bad_flags = PAGE_FLAGS_CHECK_AT_FREE; + if (unlikely(page->flags.f & flags)) { + if (flags == PAGE_FLAGS_CHECK_AT_PREP) + bad_reason = "PAGE_FLAGS_CHECK_AT_PREP flag(s) set"; + else + bad_reason = "PAGE_FLAGS_CHECK_AT_FREE flag(s) set"; } #ifdef CONFIG_MEMCG - if (unlikely(page->mem_cgroup)) + if (unlikely(page->memcg_data)) bad_reason = "page still charged to cgroup"; #endif - bad_page(page, bad_reason, bad_flags); + if (unlikely(page_pool_page_is_pp(page))) + bad_reason = "page_pool leak"; + return bad_reason; } -static inline int free_pages_check(struct page *page) +static inline bool free_page_is_bad(struct page *page) { if (likely(page_expected_state(page, PAGE_FLAGS_CHECK_AT_FREE))) - return 0; + return false; /* Something has gone sideways, find it */ - free_pages_check_bad(page); - return 1; + bad_page(page, page_bad_reason(page, PAGE_FLAGS_CHECK_AT_FREE)); + return true; } -static int free_tail_pages_check(struct page *head_page, struct page *page) +static inline bool is_check_pages_enabled(void) { + return static_branch_unlikely(&check_pages_enabled); +} + +static int free_tail_page_prepare(struct page *head_page, struct page *page) +{ + struct folio *folio = (struct folio *)head_page; int ret = 1; /* @@ -982,37 +1100,78 @@ static int free_tail_pages_check(struct page *head_page, struct page *page) */ BUILD_BUG_ON((unsigned long)LIST_POISON1 & 1); - if (!IS_ENABLED(CONFIG_DEBUG_VM)) { + if (!is_check_pages_enabled()) { ret = 0; goto out; } switch (page - head_page) { case 1: - /* the first tail page: ->mapping may be compound_mapcount() */ - if (unlikely(compound_mapcount(page))) { - bad_page(page, "nonzero compound_mapcount", 0); + /* the first tail page: these may be in place of ->mapping */ + if (unlikely(folio_large_mapcount(folio))) { + bad_page(page, "nonzero large_mapcount"); goto out; } + if (IS_ENABLED(CONFIG_PAGE_MAPCOUNT) && + unlikely(atomic_read(&folio->_nr_pages_mapped))) { + bad_page(page, "nonzero nr_pages_mapped"); + goto out; + } + if (IS_ENABLED(CONFIG_MM_ID)) { + if (unlikely(folio->_mm_id_mapcount[0] != -1)) { + bad_page(page, "nonzero mm mapcount 0"); + goto out; + } + if (unlikely(folio->_mm_id_mapcount[1] != -1)) { + bad_page(page, "nonzero mm mapcount 1"); + goto out; + } + } + if (IS_ENABLED(CONFIG_64BIT)) { + if (unlikely(atomic_read(&folio->_entire_mapcount) + 1)) { + bad_page(page, "nonzero entire_mapcount"); + goto out; + } + if (unlikely(atomic_read(&folio->_pincount))) { + bad_page(page, "nonzero pincount"); + goto out; + } + } break; case 2: - /* - * the second tail page: ->mapping is - * deferred_list.next -- ignore value. - */ + /* the second tail page: deferred_list overlaps ->mapping */ + if (unlikely(!list_empty(&folio->_deferred_list))) { + bad_page(page, "on deferred list"); + goto out; + } + if (!IS_ENABLED(CONFIG_64BIT)) { + if (unlikely(atomic_read(&folio->_entire_mapcount) + 1)) { + bad_page(page, "nonzero entire_mapcount"); + goto out; + } + if (unlikely(atomic_read(&folio->_pincount))) { + bad_page(page, "nonzero pincount"); + goto out; + } + } break; + case 3: + /* the third tail page: hugetlb specifics overlap ->mappings */ + if (IS_ENABLED(CONFIG_HUGETLB_PAGE)) + break; + fallthrough; default: if (page->mapping != TAIL_MAPPING) { - bad_page(page, "corrupted mapping in tail page", 0); + bad_page(page, "corrupted mapping in tail page"); goto out; } break; } if (unlikely(!PageTail(page))) { - bad_page(page, "PageTail not set", 0); + bad_page(page, "PageTail not set"); goto out; } if (unlikely(compound_head(page) != head_page)) { - bad_page(page, "compound_head not consistent", 0); + bad_page(page, "compound_head not consistent"); goto out; } ret = 0; @@ -1022,49 +1181,220 @@ out: return ret; } -static __always_inline bool free_pages_prepare(struct page *page, - unsigned int order, bool check_free) +/* + * Skip KASAN memory poisoning when either: + * + * 1. For generic KASAN: deferred memory initialization has not yet completed. + * Tag-based KASAN modes skip pages freed via deferred memory initialization + * using page tags instead (see below). + * 2. For tag-based KASAN modes: the page has a match-all KASAN tag, indicating + * that error detection is disabled for accesses via the page address. + * + * Pages will have match-all tags in the following circumstances: + * + * 1. Pages are being initialized for the first time, including during deferred + * memory init; see the call to page_kasan_tag_reset in __init_single_page. + * 2. The allocation was not unpoisoned due to __GFP_SKIP_KASAN, with the + * exception of pages unpoisoned by kasan_unpoison_vmalloc. + * 3. The allocation was excluded from being checked due to sampling, + * see the call to kasan_unpoison_pages. + * + * Poisoning pages during deferred memory init will greatly lengthen the + * process and cause problem in large memory systems as the deferred pages + * initialization is done with interrupt disabled. + * + * Assuming that there will be no reference to those newly initialized + * pages before they are ever allocated, this should have no effect on + * KASAN memory tracking as the poison will be properly inserted at page + * allocation time. The only corner case is when pages are allocated by + * on-demand allocation and then freed again before the deferred pages + * initialization is done, but this is not likely to happen. + */ +static inline bool should_skip_kasan_poison(struct page *page) +{ + if (IS_ENABLED(CONFIG_KASAN_GENERIC)) + return deferred_pages_enabled(); + + return page_kasan_tag(page) == KASAN_TAG_KERNEL; +} + +static void kernel_init_pages(struct page *page, int numpages) +{ + int i; + + /* s390's use of memset() could override KASAN redzones. */ + kasan_disable_current(); + for (i = 0; i < numpages; i++) + clear_highpage_kasan_tagged(page + i); + kasan_enable_current(); +} + +#ifdef CONFIG_MEM_ALLOC_PROFILING + +/* Should be called only if mem_alloc_profiling_enabled() */ +void __clear_page_tag_ref(struct page *page) +{ + union pgtag_ref_handle handle; + union codetag_ref ref; + + if (get_page_tag_ref(page, &ref, &handle)) { + set_codetag_empty(&ref); + update_page_tag_ref(handle, &ref); + put_page_tag_ref(handle); + } +} + +/* Should be called only if mem_alloc_profiling_enabled() */ +static noinline +void __pgalloc_tag_add(struct page *page, struct task_struct *task, + unsigned int nr) +{ + union pgtag_ref_handle handle; + union codetag_ref ref; + + if (get_page_tag_ref(page, &ref, &handle)) { + alloc_tag_add(&ref, task->alloc_tag, PAGE_SIZE * nr); + update_page_tag_ref(handle, &ref); + put_page_tag_ref(handle); + } +} + +static inline void pgalloc_tag_add(struct page *page, struct task_struct *task, + unsigned int nr) +{ + if (mem_alloc_profiling_enabled()) + __pgalloc_tag_add(page, task, nr); +} + +/* Should be called only if mem_alloc_profiling_enabled() */ +static noinline +void __pgalloc_tag_sub(struct page *page, unsigned int nr) +{ + union pgtag_ref_handle handle; + union codetag_ref ref; + + if (get_page_tag_ref(page, &ref, &handle)) { + alloc_tag_sub(&ref, PAGE_SIZE * nr); + update_page_tag_ref(handle, &ref); + put_page_tag_ref(handle); + } +} + +static inline void pgalloc_tag_sub(struct page *page, unsigned int nr) +{ + if (mem_alloc_profiling_enabled()) + __pgalloc_tag_sub(page, nr); +} + +/* When tag is not NULL, assuming mem_alloc_profiling_enabled */ +static inline void pgalloc_tag_sub_pages(struct alloc_tag *tag, unsigned int nr) +{ + if (tag) + this_cpu_sub(tag->counters->bytes, PAGE_SIZE * nr); +} + +#else /* CONFIG_MEM_ALLOC_PROFILING */ + +static inline void pgalloc_tag_add(struct page *page, struct task_struct *task, + unsigned int nr) {} +static inline void pgalloc_tag_sub(struct page *page, unsigned int nr) {} +static inline void pgalloc_tag_sub_pages(struct alloc_tag *tag, unsigned int nr) {} + +#endif /* CONFIG_MEM_ALLOC_PROFILING */ + +__always_inline bool free_pages_prepare(struct page *page, + unsigned int order) { int bad = 0; + bool skip_kasan_poison = should_skip_kasan_poison(page); + bool init = want_init_on_free(); + bool compound = PageCompound(page); + struct folio *folio = page_folio(page); VM_BUG_ON_PAGE(PageTail(page), page); trace_mm_page_free(page, order); + kmsan_free_page(page, order); + + if (memcg_kmem_online() && PageMemcgKmem(page)) + __memcg_kmem_uncharge_page(page, order); + + /* + * In rare cases, when truncation or holepunching raced with + * munlock after VM_LOCKED was cleared, Mlocked may still be + * found set here. This does not indicate a problem, unless + * "unevictable_pgs_cleared" appears worryingly large. + */ + if (unlikely(folio_test_mlocked(folio))) { + long nr_pages = folio_nr_pages(folio); + + __folio_clear_mlocked(folio); + zone_stat_mod_folio(folio, NR_MLOCK, -nr_pages); + count_vm_events(UNEVICTABLE_PGCLEARED, nr_pages); + } + + if (unlikely(PageHWPoison(page)) && !order) { + /* Do not let hwpoison pages hit pcplists/buddy */ + reset_page_owner(page, order); + page_table_check_free(page, order); + pgalloc_tag_sub(page, 1 << order); + + /* + * The page is isolated and accounted for. + * Mark the codetag as empty to avoid accounting error + * when the page is freed by unpoison_memory(). + */ + clear_page_tag_ref(page); + return false; + } + + VM_BUG_ON_PAGE(compound && compound_order(page) != order, page); /* * Check tail pages before head page information is cleared to * avoid checking PageCompound for order-0 pages. */ if (unlikely(order)) { - bool compound = PageCompound(page); int i; - VM_BUG_ON_PAGE(compound && compound_order(page) != order, page); - - if (compound) - ClearPageDoubleMap(page); + if (compound) { + page[1].flags.f &= ~PAGE_FLAGS_SECOND; +#ifdef NR_PAGES_IN_LARGE_FOLIO + folio->_nr_pages = 0; +#endif + } for (i = 1; i < (1 << order); i++) { if (compound) - bad += free_tail_pages_check(page, page + i); - if (unlikely(free_pages_check(page + i))) { - bad++; - continue; + bad += free_tail_page_prepare(page, page + i); + if (is_check_pages_enabled()) { + if (free_page_is_bad(page + i)) { + bad++; + continue; + } } - (page + i)->flags &= ~PAGE_FLAGS_CHECK_AT_PREP; + (page + i)->flags.f &= ~PAGE_FLAGS_CHECK_AT_PREP; } } - if (PageMappingFlags(page)) - page->mapping = NULL; - if (memcg_kmem_enabled() && PageKmemcg(page)) - memcg_kmem_uncharge(page, order); - if (check_free) - bad += free_pages_check(page); - if (bad) - return false; + if (folio_test_anon(folio)) { + mod_mthp_stat(order, MTHP_STAT_NR_ANON, -1); + folio->mapping = NULL; + } + if (unlikely(page_has_type(page))) + /* Reset the page_type (which overlays _mapcount) */ + page->page_type = UINT_MAX; + + if (is_check_pages_enabled()) { + if (free_page_is_bad(page)) + bad++; + if (bad) + return false; + } page_cpupid_reset_last(page); - page->flags &= ~PAGE_FLAGS_CHECK_AT_PREP; + page->flags.f &= ~PAGE_FLAGS_CHECK_AT_PREP; reset_page_owner(page, order); + page_table_check_free(page, order); + pgalloc_tag_sub(page, 1 << order); if (!PageHighMem(page)) { debug_check_no_locks_freed(page_address(page), @@ -1072,325 +1402,228 @@ static __always_inline bool free_pages_prepare(struct page *page, debug_check_no_obj_freed(page_address(page), PAGE_SIZE << order); } - arch_free_page(page, order); - kernel_poison_pages(page, 1 << order, 0); - kernel_map_pages(page, 1 << order, 0); - kasan_free_nondeferred_pages(page, order); - return true; -} + kernel_poison_pages(page, 1 << order); -#ifdef CONFIG_DEBUG_VM -static inline bool free_pcp_prepare(struct page *page) -{ - return free_pages_prepare(page, 0, true); -} + /* + * As memory initialization might be integrated into KASAN, + * KASAN poisoning and memory initialization code must be + * kept together to avoid discrepancies in behavior. + * + * With hardware tag-based KASAN, memory tags must be set before the + * page becomes unavailable via debug_pagealloc or arch_free_page. + */ + if (!skip_kasan_poison) { + kasan_poison_pages(page, order, init); -static inline bool bulkfree_pcp_prepare(struct page *page) -{ - return false; -} -#else -static bool free_pcp_prepare(struct page *page) -{ - return free_pages_prepare(page, 0, false); -} + /* Memory is already initialized if KASAN did it internally. */ + if (kasan_has_integrated_init()) + init = false; + } + if (init) + kernel_init_pages(page, 1 << order); -static bool bulkfree_pcp_prepare(struct page *page) -{ - return free_pages_check(page); -} -#endif /* CONFIG_DEBUG_VM */ + /* + * arch_free_page() can make the page's contents inaccessible. s390 + * does this. So nothing which can access the page's contents should + * happen after this. + */ + arch_free_page(page, order); -static inline void prefetch_buddy(struct page *page) -{ - unsigned long pfn = page_to_pfn(page); - unsigned long buddy_pfn = __find_buddy_pfn(pfn, 0); - struct page *buddy = page + (buddy_pfn - pfn); + debug_pagealloc_unmap_pages(page, 1 << order); - prefetch(buddy); + return true; } /* * Frees a number of pages from the PCP lists - * Assumes all pages on list are in same zone, and of same order. + * Assumes all pages on list are in same zone. * count is the number of pages to free. - * - * If the zone was previously in an "all pages pinned" state then look to - * see if this freeing clears that state. - * - * And clear the zone's pages_scanned counter, to hold off the "all pages are - * pinned" detection logic. */ static void free_pcppages_bulk(struct zone *zone, int count, - struct per_cpu_pages *pcp) + struct per_cpu_pages *pcp, + int pindex) { - int migratetype = 0; - int batch_free = 0; - int prefetch_nr = 0; - bool isolated_pageblocks; - struct page *page, *tmp; - LIST_HEAD(head); + unsigned long flags; + unsigned int order; + struct page *page; + + /* + * Ensure proper count is passed which otherwise would stuck in the + * below while (list_empty(list)) loop. + */ + count = min(pcp->count, count); + + /* Ensure requested pindex is drained first. */ + pindex = pindex - 1; - while (count) { + spin_lock_irqsave(&zone->lock, flags); + + while (count > 0) { struct list_head *list; + int nr_pages; - /* - * Remove pages from lists in a round-robin fashion. A - * batch_free count is maintained that is incremented when an - * empty list is encountered. This is so more pages are freed - * off fuller lists instead of spinning excessively around empty - * lists - */ + /* Remove pages from lists in a round-robin fashion. */ do { - batch_free++; - if (++migratetype == MIGRATE_PCPTYPES) - migratetype = 0; - list = &pcp->lists[migratetype]; + if (++pindex > NR_PCP_LISTS - 1) + pindex = 0; + list = &pcp->lists[pindex]; } while (list_empty(list)); - /* This is the only non-empty list. Free them all. */ - if (batch_free == MIGRATE_PCPTYPES) - batch_free = count; - + order = pindex_to_order(pindex); + nr_pages = 1 << order; do { - page = list_last_entry(list, struct page, lru); - /* must delete to avoid corrupting pcp list */ - list_del(&page->lru); - pcp->count--; - - if (bulkfree_pcp_prepare(page)) - continue; + unsigned long pfn; + int mt; - list_add_tail(&page->lru, &head); - - /* - * We are going to put the page back to the global - * pool, prefetch its buddy to speed up later access - * under zone->lock. It is believed the overhead of - * an additional test and calculating buddy_pfn here - * can be offset by reduced memory latency later. To - * avoid excessive prefetching due to large count, only - * prefetch buddy for the first pcp->batch nr of pages. - */ - if (prefetch_nr++ < pcp->batch) - prefetch_buddy(page); - } while (--count && --batch_free && !list_empty(list)); - } - - spin_lock(&zone->lock); - isolated_pageblocks = has_isolate_pageblock(zone); + page = list_last_entry(list, struct page, pcp_list); + pfn = page_to_pfn(page); + mt = get_pfnblock_migratetype(page, pfn); - /* - * Use safe version since after __free_one_page(), - * page->lru.next will not point to original list. - */ - list_for_each_entry_safe(page, tmp, &head, lru) { - int mt = get_pcppage_migratetype(page); - /* MIGRATE_ISOLATE page should not go to pcplists */ - VM_BUG_ON_PAGE(is_migrate_isolate(mt), page); - /* Pageblock could have been isolated meanwhile */ - if (unlikely(isolated_pageblocks)) - mt = get_pageblock_migratetype(page); + /* must delete to avoid corrupting pcp list */ + list_del(&page->pcp_list); + count -= nr_pages; + pcp->count -= nr_pages; - __free_one_page(page, page_to_pfn(page), zone, 0, mt); - trace_mm_page_pcpu_drain(page, 0, mt); + __free_one_page(page, pfn, zone, order, mt, FPI_NONE); + trace_mm_page_pcpu_drain(page, order, mt); + } while (count > 0 && !list_empty(list)); } - spin_unlock(&zone->lock); -} -static void free_one_page(struct zone *zone, - struct page *page, unsigned long pfn, - unsigned int order, - int migratetype) -{ - spin_lock(&zone->lock); - if (unlikely(has_isolate_pageblock(zone) || - is_migrate_isolate(migratetype))) { - migratetype = get_pfnblock_migratetype(page, pfn); - } - __free_one_page(page, pfn, zone, order, migratetype); - spin_unlock(&zone->lock); -} - -static void __meminit __init_single_page(struct page *page, unsigned long pfn, - unsigned long zone, int nid) -{ - mm_zero_struct_page(page); - set_page_links(page, zone, nid, pfn); - init_page_count(page); - page_mapcount_reset(page); - page_cpupid_reset_last(page); - page_kasan_tag_reset(page); - - INIT_LIST_HEAD(&page->lru); -#ifdef WANT_PAGE_VIRTUAL - /* The shift won't overflow because ZONE_NORMAL is below 4G. */ - if (!is_highmem_idx(zone)) - set_page_address(page, __va(pfn << PAGE_SHIFT)); -#endif + spin_unlock_irqrestore(&zone->lock, flags); } -#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT -static void __meminit init_reserved_page(unsigned long pfn) +/* Split a multi-block free page into its individual pageblocks. */ +static void split_large_buddy(struct zone *zone, struct page *page, + unsigned long pfn, int order, fpi_t fpi) { - pg_data_t *pgdat; - int nid, zid; + unsigned long end = pfn + (1 << order); - if (!early_page_uninitialised(pfn)) - return; + VM_WARN_ON_ONCE(!IS_ALIGNED(pfn, 1 << order)); + /* Caller removed page from freelist, buddy info cleared! */ + VM_WARN_ON_ONCE(PageBuddy(page)); - nid = early_pfn_to_nid(pfn); - pgdat = NODE_DATA(nid); + if (order > pageblock_order) + order = pageblock_order; - for (zid = 0; zid < MAX_NR_ZONES; zid++) { - struct zone *zone = &pgdat->node_zones[zid]; + do { + int mt = get_pfnblock_migratetype(page, pfn); - if (pfn >= zone->zone_start_pfn && pfn < zone_end_pfn(zone)) + __free_one_page(page, pfn, zone, order, mt, fpi); + pfn += 1 << order; + if (pfn == end) break; - } - __init_single_page(pfn_to_page(pfn), pfn, zid, nid); + page = pfn_to_page(pfn); + } while (1); } -#else -static inline void init_reserved_page(unsigned long pfn) + +static void add_page_to_zone_llist(struct zone *zone, struct page *page, + unsigned int order) { + /* Remember the order */ + page->private = order; + /* Add the page to the free list */ + llist_add(&page->pcp_llist, &zone->trylock_free_pages); } -#endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */ -/* - * Initialised pages do not have PageReserved set. This function is - * called for each range allocated by the bootmem allocator and - * marks the pages PageReserved. The remaining valid pages are later - * sent to the buddy page allocator. - */ -void __meminit reserve_bootmem_region(phys_addr_t start, phys_addr_t end) +static void free_one_page(struct zone *zone, struct page *page, + unsigned long pfn, unsigned int order, + fpi_t fpi_flags) { - unsigned long start_pfn = PFN_DOWN(start); - unsigned long end_pfn = PFN_UP(end); + struct llist_head *llhead; + unsigned long flags; - for (; start_pfn < end_pfn; start_pfn++) { - if (pfn_valid(start_pfn)) { - struct page *page = pfn_to_page(start_pfn); + if (unlikely(fpi_flags & FPI_TRYLOCK)) { + if (!spin_trylock_irqsave(&zone->lock, flags)) { + add_page_to_zone_llist(zone, page, order); + return; + } + } else { + spin_lock_irqsave(&zone->lock, flags); + } - init_reserved_page(start_pfn); + /* The lock succeeded. Process deferred pages. */ + llhead = &zone->trylock_free_pages; + if (unlikely(!llist_empty(llhead) && !(fpi_flags & FPI_TRYLOCK))) { + struct llist_node *llnode; + struct page *p, *tmp; - /* Avoid false-positive PageTail() */ - INIT_LIST_HEAD(&page->lru); + llnode = llist_del_all(llhead); + llist_for_each_entry_safe(p, tmp, llnode, pcp_llist) { + unsigned int p_order = p->private; - /* - * no need for atomic set_bit because the struct - * page is not visible yet so nobody should - * access it yet. - */ - __SetPageReserved(page); + split_large_buddy(zone, p, page_to_pfn(p), p_order, fpi_flags); + __count_vm_events(PGFREE, 1 << p_order); } } + split_large_buddy(zone, page, pfn, order, fpi_flags); + spin_unlock_irqrestore(&zone->lock, flags); + + __count_vm_events(PGFREE, 1 << order); } -static void __free_pages_ok(struct page *page, unsigned int order) +static void __free_pages_ok(struct page *page, unsigned int order, + fpi_t fpi_flags) { - unsigned long flags; - int migratetype; unsigned long pfn = page_to_pfn(page); + struct zone *zone = page_zone(page); - if (!free_pages_prepare(page, order, true)) - return; - - migratetype = get_pfnblock_migratetype(page, pfn); - local_irq_save(flags); - __count_vm_events(PGFREE, 1 << order); - free_one_page(page_zone(page), page, pfn, order, migratetype); - local_irq_restore(flags); + if (free_pages_prepare(page, order)) + free_one_page(zone, page, pfn, order, fpi_flags); } -static void __init __free_pages_boot_core(struct page *page, unsigned int order) +void __meminit __free_pages_core(struct page *page, unsigned int order, + enum meminit_context context) { unsigned int nr_pages = 1 << order; struct page *p = page; unsigned int loop; - prefetchw(p); - for (loop = 0; loop < (nr_pages - 1); loop++, p++) { - prefetchw(p + 1); - __ClearPageReserved(p); - set_page_count(p, 0); - } - __ClearPageReserved(p); - set_page_count(p, 0); - - atomic_long_add(nr_pages, &page_zone(page)->managed_pages); - set_page_refcounted(page); - __free_pages(page, order); -} - -#if defined(CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID) || \ - defined(CONFIG_HAVE_MEMBLOCK_NODE_MAP) - -static struct mminit_pfnnid_cache early_pfnnid_cache __meminitdata; - -int __meminit early_pfn_to_nid(unsigned long pfn) -{ - static DEFINE_SPINLOCK(early_pfn_lock); - int nid; - - spin_lock(&early_pfn_lock); - nid = __early_pfn_to_nid(pfn, &early_pfnnid_cache); - if (nid < 0) - nid = first_online_node; - spin_unlock(&early_pfn_lock); - - return nid; -} -#endif - -#ifdef CONFIG_NODES_SPAN_OTHER_NODES -static inline bool __meminit __maybe_unused -meminit_pfn_in_nid(unsigned long pfn, int node, - struct mminit_pfnnid_cache *state) -{ - int nid; - - nid = __early_pfn_to_nid(pfn, state); - if (nid >= 0 && nid != node) - return false; - return true; -} + /* + * When initializing the memmap, __init_single_page() sets the refcount + * of all pages to 1 ("allocated"/"not free"). We have to set the + * refcount of all involved pages to 0. + * + * Note that hotplugged memory pages are initialized to PageOffline(). + * Pages freed from memblock might be marked as reserved. + */ + if (IS_ENABLED(CONFIG_MEMORY_HOTPLUG) && + unlikely(context == MEMINIT_HOTPLUG)) { + for (loop = 0; loop < nr_pages; loop++, p++) { + VM_WARN_ON_ONCE(PageReserved(p)); + __ClearPageOffline(p); + set_page_count(p, 0); + } -/* Only safe to use early in boot when initialisation is single-threaded */ -static inline bool __meminit early_pfn_in_nid(unsigned long pfn, int node) -{ - return meminit_pfn_in_nid(pfn, node, &early_pfnnid_cache); -} + adjust_managed_page_count(page, nr_pages); + } else { + for (loop = 0; loop < nr_pages; loop++, p++) { + __ClearPageReserved(p); + set_page_count(p, 0); + } -#else + /* memblock adjusts totalram_pages() manually. */ + atomic_long_add(nr_pages, &page_zone(page)->managed_pages); + } -static inline bool __meminit early_pfn_in_nid(unsigned long pfn, int node) -{ - return true; -} -static inline bool __meminit __maybe_unused -meminit_pfn_in_nid(unsigned long pfn, int node, - struct mminit_pfnnid_cache *state) -{ - return true; -} -#endif + if (page_contains_unaccepted(page, order)) { + if (order == MAX_PAGE_ORDER && __free_unaccepted(page)) + return; + accept_memory(page_to_phys(page), PAGE_SIZE << order); + } -void __init memblock_free_pages(struct page *page, unsigned long pfn, - unsigned int order) -{ - if (early_page_uninitialised(pfn)) - return; - return __free_pages_boot_core(page, order); + /* + * Bypass PCP and place fresh pages right to the tail, primarily + * relevant for memory onlining. + */ + __free_pages_ok(page, order, FPI_TO_TAIL); } /* * Check that the whole (or subset of) a pageblock given by the interval of * [start_pfn, end_pfn) is valid and within the same zone, before scanning it - * with the migration of free compaction scanner. The scanners then need to - * use only pfn_valid_within() check for arches that allow holes within - * pageblocks. + * with the migration of free compaction scanner. * * Return struct page pointer of start_pfn, or NULL if checks were not passed. * @@ -1401,6 +1634,15 @@ void __init memblock_free_pages(struct page *page, unsigned long pfn, * interleaving within a single pageblock. It is therefore sufficient to check * the first and last page of a pageblock and avoid checking each individual * page in a pageblock. + * + * Note: the function may return non-NULL struct page even for a page block + * which contains a memory hole (i.e. there is no physical memory for a subset + * of the pfn range). For example, if the pageblock order is MAX_PAGE_ORDER, which + * will fall into 2 sub-sections, and the end pfn of the pageblock may be hole + * even though the start pfn is online and valid. This should be safe most of + * the time because struct pages are still initialized via init_unavailable_range() + * and pfn walkers shouldn't touch any physical memory range for which they do + * not recognize any specific metadata in struct pages. */ struct page *__pageblock_pfn_to_page(unsigned long start_pfn, unsigned long end_pfn, struct zone *zone) @@ -1411,7 +1653,7 @@ struct page *__pageblock_pfn_to_page(unsigned long start_pfn, /* end_pfn is one past the range we are checking */ end_pfn--; - if (!pfn_valid(start_pfn) || !pfn_valid(end_pfn)) + if (!pfn_valid(end_pfn)) return NULL; start_page = pfn_to_online_page(start_pfn); @@ -1430,390 +1672,6 @@ struct page *__pageblock_pfn_to_page(unsigned long start_pfn, return start_page; } -void set_zone_contiguous(struct zone *zone) -{ - unsigned long block_start_pfn = zone->zone_start_pfn; - unsigned long block_end_pfn; - - block_end_pfn = ALIGN(block_start_pfn + 1, pageblock_nr_pages); - for (; block_start_pfn < zone_end_pfn(zone); - block_start_pfn = block_end_pfn, - block_end_pfn += pageblock_nr_pages) { - - block_end_pfn = min(block_end_pfn, zone_end_pfn(zone)); - - if (!__pageblock_pfn_to_page(block_start_pfn, - block_end_pfn, zone)) - return; - } - - /* We confirm that there is no hole */ - zone->contiguous = true; -} - -void clear_zone_contiguous(struct zone *zone) -{ - zone->contiguous = false; -} - -#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT -static void __init deferred_free_range(unsigned long pfn, - unsigned long nr_pages) -{ - struct page *page; - unsigned long i; - - if (!nr_pages) - return; - - page = pfn_to_page(pfn); - - /* Free a large naturally-aligned chunk if possible */ - if (nr_pages == pageblock_nr_pages && - (pfn & (pageblock_nr_pages - 1)) == 0) { - set_pageblock_migratetype(page, MIGRATE_MOVABLE); - __free_pages_boot_core(page, pageblock_order); - return; - } - - for (i = 0; i < nr_pages; i++, page++, pfn++) { - if ((pfn & (pageblock_nr_pages - 1)) == 0) - set_pageblock_migratetype(page, MIGRATE_MOVABLE); - __free_pages_boot_core(page, 0); - } -} - -/* Completion tracking for deferred_init_memmap() threads */ -static atomic_t pgdat_init_n_undone __initdata; -static __initdata DECLARE_COMPLETION(pgdat_init_all_done_comp); - -static inline void __init pgdat_init_report_one_done(void) -{ - if (atomic_dec_and_test(&pgdat_init_n_undone)) - complete(&pgdat_init_all_done_comp); -} - -/* - * Returns true if page needs to be initialized or freed to buddy allocator. - * - * First we check if pfn is valid on architectures where it is possible to have - * holes within pageblock_nr_pages. On systems where it is not possible, this - * function is optimized out. - * - * Then, we check if a current large page is valid by only checking the validity - * of the head pfn. - * - * Finally, meminit_pfn_in_nid is checked on systems where pfns can interleave - * within a node: a pfn is between start and end of a node, but does not belong - * to this memory node. - */ -static inline bool __init -deferred_pfn_valid(int nid, unsigned long pfn, - struct mminit_pfnnid_cache *nid_init_state) -{ - if (!pfn_valid_within(pfn)) - return false; - if (!(pfn & (pageblock_nr_pages - 1)) && !pfn_valid(pfn)) - return false; - if (!meminit_pfn_in_nid(pfn, nid, nid_init_state)) - return false; - return true; -} - -/* - * Free pages to buddy allocator. Try to free aligned pages in - * pageblock_nr_pages sizes. - */ -static void __init deferred_free_pages(int nid, int zid, unsigned long pfn, - unsigned long end_pfn) -{ - struct mminit_pfnnid_cache nid_init_state = { }; - unsigned long nr_pgmask = pageblock_nr_pages - 1; - unsigned long nr_free = 0; - - for (; pfn < end_pfn; pfn++) { - if (!deferred_pfn_valid(nid, pfn, &nid_init_state)) { - deferred_free_range(pfn - nr_free, nr_free); - nr_free = 0; - } else if (!(pfn & nr_pgmask)) { - deferred_free_range(pfn - nr_free, nr_free); - nr_free = 1; - touch_nmi_watchdog(); - } else { - nr_free++; - } - } - /* Free the last block of pages to allocator */ - deferred_free_range(pfn - nr_free, nr_free); -} - -/* - * Initialize struct pages. We minimize pfn page lookups and scheduler checks - * by performing it only once every pageblock_nr_pages. - * Return number of pages initialized. - */ -static unsigned long __init deferred_init_pages(int nid, int zid, - unsigned long pfn, - unsigned long end_pfn) -{ - struct mminit_pfnnid_cache nid_init_state = { }; - unsigned long nr_pgmask = pageblock_nr_pages - 1; - unsigned long nr_pages = 0; - struct page *page = NULL; - - for (; pfn < end_pfn; pfn++) { - if (!deferred_pfn_valid(nid, pfn, &nid_init_state)) { - page = NULL; - continue; - } else if (!page || !(pfn & nr_pgmask)) { - page = pfn_to_page(pfn); - touch_nmi_watchdog(); - } else { - page++; - } - __init_single_page(page, pfn, zid, nid); - nr_pages++; - } - return (nr_pages); -} - -/* Initialise remaining memory on a node */ -static int __init deferred_init_memmap(void *data) -{ - pg_data_t *pgdat = data; - int nid = pgdat->node_id; - unsigned long start = jiffies; - unsigned long nr_pages = 0; - unsigned long spfn, epfn, first_init_pfn, flags; - phys_addr_t spa, epa; - int zid; - struct zone *zone; - const struct cpumask *cpumask = cpumask_of_node(pgdat->node_id); - u64 i; - - /* Bind memory initialisation thread to a local node if possible */ - if (!cpumask_empty(cpumask)) - set_cpus_allowed_ptr(current, cpumask); - - pgdat_resize_lock(pgdat, &flags); - first_init_pfn = pgdat->first_deferred_pfn; - if (first_init_pfn == ULONG_MAX) { - pgdat_resize_unlock(pgdat, &flags); - pgdat_init_report_one_done(); - return 0; - } - - /* Sanity check boundaries */ - BUG_ON(pgdat->first_deferred_pfn < pgdat->node_start_pfn); - BUG_ON(pgdat->first_deferred_pfn > pgdat_end_pfn(pgdat)); - pgdat->first_deferred_pfn = ULONG_MAX; - - /* Only the highest zone is deferred so find it */ - for (zid = 0; zid < MAX_NR_ZONES; zid++) { - zone = pgdat->node_zones + zid; - if (first_init_pfn < zone_end_pfn(zone)) - break; - } - first_init_pfn = max(zone->zone_start_pfn, first_init_pfn); - - /* - * Initialize and free pages. We do it in two loops: first we initialize - * struct page, than free to buddy allocator, because while we are - * freeing pages we can access pages that are ahead (computing buddy - * page in __free_one_page()). - */ - for_each_free_mem_range(i, nid, MEMBLOCK_NONE, &spa, &epa, NULL) { - spfn = max_t(unsigned long, first_init_pfn, PFN_UP(spa)); - epfn = min_t(unsigned long, zone_end_pfn(zone), PFN_DOWN(epa)); - nr_pages += deferred_init_pages(nid, zid, spfn, epfn); - } - for_each_free_mem_range(i, nid, MEMBLOCK_NONE, &spa, &epa, NULL) { - spfn = max_t(unsigned long, first_init_pfn, PFN_UP(spa)); - epfn = min_t(unsigned long, zone_end_pfn(zone), PFN_DOWN(epa)); - deferred_free_pages(nid, zid, spfn, epfn); - } - pgdat_resize_unlock(pgdat, &flags); - - /* Sanity check that the next zone really is unpopulated */ - WARN_ON(++zid < MAX_NR_ZONES && populated_zone(++zone)); - - pr_info("node %d initialised, %lu pages in %ums\n", nid, nr_pages, - jiffies_to_msecs(jiffies - start)); - - pgdat_init_report_one_done(); - return 0; -} - -/* - * If this zone has deferred pages, try to grow it by initializing enough - * deferred pages to satisfy the allocation specified by order, rounded up to - * the nearest PAGES_PER_SECTION boundary. So we're adding memory in increments - * of SECTION_SIZE bytes by initializing struct pages in increments of - * PAGES_PER_SECTION * sizeof(struct page) bytes. - * - * Return true when zone was grown, otherwise return false. We return true even - * when we grow less than requested, to let the caller decide if there are - * enough pages to satisfy the allocation. - * - * Note: We use noinline because this function is needed only during boot, and - * it is called from a __ref function _deferred_grow_zone. This way we are - * making sure that it is not inlined into permanent text section. - */ -static noinline bool __init -deferred_grow_zone(struct zone *zone, unsigned int order) -{ - int zid = zone_idx(zone); - int nid = zone_to_nid(zone); - pg_data_t *pgdat = NODE_DATA(nid); - unsigned long nr_pages_needed = ALIGN(1 << order, PAGES_PER_SECTION); - unsigned long nr_pages = 0; - unsigned long first_init_pfn, spfn, epfn, t, flags; - unsigned long first_deferred_pfn = pgdat->first_deferred_pfn; - phys_addr_t spa, epa; - u64 i; - - /* Only the last zone may have deferred pages */ - if (zone_end_pfn(zone) != pgdat_end_pfn(pgdat)) - return false; - - pgdat_resize_lock(pgdat, &flags); - - /* - * If deferred pages have been initialized while we were waiting for - * the lock, return true, as the zone was grown. The caller will retry - * this zone. We won't return to this function since the caller also - * has this static branch. - */ - if (!static_branch_unlikely(&deferred_pages)) { - pgdat_resize_unlock(pgdat, &flags); - return true; - } - - /* - * If someone grew this zone while we were waiting for spinlock, return - * true, as there might be enough pages already. - */ - if (first_deferred_pfn != pgdat->first_deferred_pfn) { - pgdat_resize_unlock(pgdat, &flags); - return true; - } - - first_init_pfn = max(zone->zone_start_pfn, first_deferred_pfn); - - if (first_init_pfn >= pgdat_end_pfn(pgdat)) { - pgdat_resize_unlock(pgdat, &flags); - return false; - } - - for_each_free_mem_range(i, nid, MEMBLOCK_NONE, &spa, &epa, NULL) { - spfn = max_t(unsigned long, first_init_pfn, PFN_UP(spa)); - epfn = min_t(unsigned long, zone_end_pfn(zone), PFN_DOWN(epa)); - - while (spfn < epfn && nr_pages < nr_pages_needed) { - t = ALIGN(spfn + PAGES_PER_SECTION, PAGES_PER_SECTION); - first_deferred_pfn = min(t, epfn); - nr_pages += deferred_init_pages(nid, zid, spfn, - first_deferred_pfn); - spfn = first_deferred_pfn; - } - - if (nr_pages >= nr_pages_needed) - break; - } - - for_each_free_mem_range(i, nid, MEMBLOCK_NONE, &spa, &epa, NULL) { - spfn = max_t(unsigned long, first_init_pfn, PFN_UP(spa)); - epfn = min_t(unsigned long, first_deferred_pfn, PFN_DOWN(epa)); - deferred_free_pages(nid, zid, spfn, epfn); - - if (first_deferred_pfn == epfn) - break; - } - pgdat->first_deferred_pfn = first_deferred_pfn; - pgdat_resize_unlock(pgdat, &flags); - - return nr_pages > 0; -} - -/* - * deferred_grow_zone() is __init, but it is called from - * get_page_from_freelist() during early boot until deferred_pages permanently - * disables this call. This is why we have refdata wrapper to avoid warning, - * and to ensure that the function body gets unloaded. - */ -static bool __ref -_deferred_grow_zone(struct zone *zone, unsigned int order) -{ - return deferred_grow_zone(zone, order); -} - -#endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */ - -void __init page_alloc_init_late(void) -{ - struct zone *zone; - -#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT - int nid; - - /* There will be num_node_state(N_MEMORY) threads */ - atomic_set(&pgdat_init_n_undone, num_node_state(N_MEMORY)); - for_each_node_state(nid, N_MEMORY) { - kthread_run(deferred_init_memmap, NODE_DATA(nid), "pgdatinit%d", nid); - } - - /* Block until all are initialised */ - wait_for_completion(&pgdat_init_all_done_comp); - - /* - * We initialized the rest of the deferred pages. Permanently disable - * on-demand struct page initialization. - */ - static_branch_disable(&deferred_pages); - - /* Reinit limits that are based on free pages after the kernel is up */ - files_maxfiles_init(); -#endif -#ifdef CONFIG_ARCH_DISCARD_MEMBLOCK - /* Discard memblock private memory */ - memblock_discard(); -#endif - - for_each_populated_zone(zone) - set_zone_contiguous(zone); -} - -#ifdef CONFIG_CMA -/* Free whole pageblock and set its migration type to MIGRATE_CMA. */ -void __init init_cma_reserved_pageblock(struct page *page) -{ - unsigned i = pageblock_nr_pages; - struct page *p = page; - - do { - __ClearPageReserved(p); - set_page_count(p, 0); - } while (++p, --i); - - set_pageblock_migratetype(page, MIGRATE_CMA); - - if (pageblock_order >= MAX_ORDER) { - i = pageblock_nr_pages; - p = page; - do { - set_page_refcounted(p); - __free_pages(p, MAX_ORDER - 1); - p += MAX_ORDER_NR_PAGES; - } while (i -= MAX_ORDER_NR_PAGES); - } else { - set_page_refcounted(page); - __free_pages(page, pageblock_order); - } - - adjust_managed_page_count(page, pageblock_nr_pages); -} -#endif - /* * The order of subdivision here is critical for the IO subsystem. * Please do not alter this order without good reasons and regression @@ -1828,14 +1686,13 @@ void __init init_cma_reserved_pageblock(struct page *page) * * -- nyc */ -static inline void expand(struct zone *zone, struct page *page, - int low, int high, struct free_area *area, - int migratetype) +static inline unsigned int expand(struct zone *zone, struct page *page, int low, + int high, int migratetype) { - unsigned long size = 1 << high; + unsigned int size = 1 << high; + unsigned int nr_added = 0; while (high > low) { - area--; high--; size >>= 1; VM_BUG_ON_PAGE(bad_range(zone, &page[size]), &page[size]); @@ -1846,121 +1703,156 @@ static inline void expand(struct zone *zone, struct page *page, * Corresponding page table entries will not be touched, * pages will stay not present in virtual address space */ - if (set_page_guard(zone, &page[size], high, migratetype)) + if (set_page_guard(zone, &page[size], high)) continue; - list_add(&page[size].lru, &area->free_list[migratetype]); - area->nr_free++; - set_page_order(&page[size], high); + __add_to_free_list(&page[size], zone, high, migratetype, false); + set_buddy_order(&page[size], high); + nr_added += size; } + + return nr_added; } -static void check_new_page_bad(struct page *page) +static __always_inline void page_del_and_expand(struct zone *zone, + struct page *page, int low, + int high, int migratetype) { - const char *bad_reason = NULL; - unsigned long bad_flags = 0; + int nr_pages = 1 << high; - if (unlikely(atomic_read(&page->_mapcount) != -1)) - bad_reason = "nonzero mapcount"; - if (unlikely(page->mapping != NULL)) - bad_reason = "non-NULL mapping"; - if (unlikely(page_ref_count(page) != 0)) - bad_reason = "nonzero _count"; - if (unlikely(page->flags & __PG_HWPOISON)) { - bad_reason = "HWPoisoned (hardware-corrupted)"; - bad_flags = __PG_HWPOISON; + __del_page_from_free_list(page, zone, high, migratetype); + nr_pages -= expand(zone, page, low, high, migratetype); + account_freepages(zone, -nr_pages, migratetype); +} + +static void check_new_page_bad(struct page *page) +{ + if (unlikely(PageHWPoison(page))) { /* Don't complain about hwpoisoned pages */ - page_mapcount_reset(page); /* remove PageBuddy */ + if (PageBuddy(page)) + __ClearPageBuddy(page); return; } - if (unlikely(page->flags & PAGE_FLAGS_CHECK_AT_PREP)) { - bad_reason = "PAGE_FLAGS_CHECK_AT_PREP flag set"; - bad_flags = PAGE_FLAGS_CHECK_AT_PREP; - } -#ifdef CONFIG_MEMCG - if (unlikely(page->mem_cgroup)) - bad_reason = "page still charged to cgroup"; -#endif - bad_page(page, bad_reason, bad_flags); + + bad_page(page, + page_bad_reason(page, PAGE_FLAGS_CHECK_AT_PREP)); } /* * This page is about to be returned from the page allocator */ -static inline int check_new_page(struct page *page) +static bool check_new_page(struct page *page) { if (likely(page_expected_state(page, PAGE_FLAGS_CHECK_AT_PREP|__PG_HWPOISON))) - return 0; + return false; check_new_page_bad(page); - return 1; + return true; } -static inline bool free_pages_prezeroed(void) +static inline bool check_new_pages(struct page *page, unsigned int order) { - return IS_ENABLED(CONFIG_PAGE_POISONING_ZERO) && - page_poisoning_enabled(); -} + if (is_check_pages_enabled()) { + for (int i = 0; i < (1 << order); i++) { + struct page *p = page + i; + + if (check_new_page(p)) + return true; + } + } -#ifdef CONFIG_DEBUG_VM -static bool check_pcp_refill(struct page *page) -{ return false; } -static bool check_new_pcp(struct page *page) -{ - return check_new_page(page); -} -#else -static bool check_pcp_refill(struct page *page) +static inline bool should_skip_kasan_unpoison(gfp_t flags) { - return check_new_page(page); -} -static bool check_new_pcp(struct page *page) -{ - return false; + /* Don't skip if a software KASAN mode is enabled. */ + if (IS_ENABLED(CONFIG_KASAN_GENERIC) || + IS_ENABLED(CONFIG_KASAN_SW_TAGS)) + return false; + + /* Skip, if hardware tag-based KASAN is not enabled. */ + if (!kasan_hw_tags_enabled()) + return true; + + /* + * With hardware tag-based KASAN enabled, skip if this has been + * requested via __GFP_SKIP_KASAN. + */ + return flags & __GFP_SKIP_KASAN; } -#endif /* CONFIG_DEBUG_VM */ -static bool check_new_pages(struct page *page, unsigned int order) +static inline bool should_skip_init(gfp_t flags) { - int i; - for (i = 0; i < (1 << order); i++) { - struct page *p = page + i; - - if (unlikely(check_new_page(p))) - return true; - } + /* Don't skip, if hardware tag-based KASAN is not enabled. */ + if (!kasan_hw_tags_enabled()) + return false; - return false; + /* For hardware tag-based KASAN, skip if requested. */ + return (flags & __GFP_SKIP_ZERO); } inline void post_alloc_hook(struct page *page, unsigned int order, gfp_t gfp_flags) { + bool init = !want_init_on_free() && want_init_on_alloc(gfp_flags) && + !should_skip_init(gfp_flags); + bool zero_tags = init && (gfp_flags & __GFP_ZEROTAGS); + int i; + set_page_private(page, 0); - set_page_refcounted(page); arch_alloc_page(page, order); - kernel_map_pages(page, 1 << order, 1); - kernel_poison_pages(page, 1 << order, 1); - kasan_alloc_pages(page, order); + debug_pagealloc_map_pages(page, 1 << order); + + /* + * Page unpoisoning must happen before memory initialization. + * Otherwise, the poison pattern will be overwritten for __GFP_ZERO + * allocations and the page unpoisoning code will complain. + */ + kernel_unpoison_pages(page, 1 << order); + + /* + * As memory initialization might be integrated into KASAN, + * KASAN unpoisoning and memory initializion code must be + * kept together to avoid discrepancies in behavior. + */ + + /* + * If memory tags should be zeroed + * (which happens only when memory should be initialized as well). + */ + if (zero_tags) + init = !tag_clear_highpages(page, 1 << order); + + if (!should_skip_kasan_unpoison(gfp_flags) && + kasan_unpoison_pages(page, order, init)) { + /* Take note that memory was initialized by KASAN. */ + if (kasan_has_integrated_init()) + init = false; + } else { + /* + * If memory tags have not been set by KASAN, reset the page + * tags to ensure page_address() dereferencing does not fault. + */ + for (i = 0; i != 1 << order; ++i) + page_kasan_tag_reset(page + i); + } + /* If memory is still not initialized, initialize it now. */ + if (init) + kernel_init_pages(page, 1 << order); + set_page_owner(page, order, gfp_flags); + page_table_check_alloc(page, order); + pgalloc_tag_add(page, current, 1 << order); } static void prep_new_page(struct page *page, unsigned int order, gfp_t gfp_flags, unsigned int alloc_flags) { - int i; - post_alloc_hook(page, order, gfp_flags); - if (!free_pages_prezeroed() && (gfp_flags & __GFP_ZERO)) - for (i = 0; i < (1 << order); i++) - clear_highpage(page + i); - if (order && (gfp_flags & __GFP_COMP)) prep_compound_page(page, order); @@ -1989,17 +1881,17 @@ struct page *__rmqueue_smallest(struct zone *zone, unsigned int order, struct page *page; /* Find a page of the appropriate size in the preferred list */ - for (current_order = order; current_order < MAX_ORDER; ++current_order) { + for (current_order = order; current_order < NR_PAGE_ORDERS; ++current_order) { area = &(zone->free_area[current_order]); - page = list_first_entry_or_null(&area->free_list[migratetype], - struct page, lru); + page = get_page_from_free_area(area, migratetype); if (!page) continue; - list_del(&page->lru); - rmv_page_order(page); - area->nr_free--; - expand(zone, page, order, current_order, area, migratetype); - set_pcppage_migratetype(page, migratetype); + + page_del_and_expand(zone, page, order, current_order, + migratetype); + trace_mm_page_alloc_zone_locked(page, order, migratetype, + pcp_allowed_order(order) && + migratetype < MIGRATE_PCPTYPES); return page; } @@ -2010,17 +1902,13 @@ struct page *__rmqueue_smallest(struct zone *zone, unsigned int order, /* * This array describes the order lists are fallen back to when * the free lists for the desirable migrate type are depleted + * + * The other migratetypes do not have fallbacks. */ -static int fallbacks[MIGRATE_TYPES][4] = { - [MIGRATE_UNMOVABLE] = { MIGRATE_RECLAIMABLE, MIGRATE_MOVABLE, MIGRATE_TYPES }, - [MIGRATE_MOVABLE] = { MIGRATE_RECLAIMABLE, MIGRATE_UNMOVABLE, MIGRATE_TYPES }, - [MIGRATE_RECLAIMABLE] = { MIGRATE_UNMOVABLE, MIGRATE_MOVABLE, MIGRATE_TYPES }, -#ifdef CONFIG_CMA - [MIGRATE_CMA] = { MIGRATE_TYPES }, /* Never used */ -#endif -#ifdef CONFIG_MEMORY_ISOLATION - [MIGRATE_ISOLATE] = { MIGRATE_TYPES }, /* Never used */ -#endif +static int fallbacks[MIGRATE_PCPTYPES][MIGRATE_PCPTYPES - 1] = { + [MIGRATE_UNMOVABLE] = { MIGRATE_RECLAIMABLE, MIGRATE_MOVABLE }, + [MIGRATE_MOVABLE] = { MIGRATE_RECLAIMABLE, MIGRATE_UNMOVABLE }, + [MIGRATE_RECLAIMABLE] = { MIGRATE_UNMOVABLE, MIGRATE_MOVABLE }, }; #ifdef CONFIG_CMA @@ -2035,88 +1923,230 @@ static inline struct page *__rmqueue_cma_fallback(struct zone *zone, #endif /* - * Move the free pages in a range to the free lists of the requested type. - * Note that start_page and end_pages are not aligned on a pageblock - * boundary. If alignment is required, use move_freepages_block() + * Move all free pages of a block to new type's freelist. Caller needs to + * change the block type. */ -static int move_freepages(struct zone *zone, - struct page *start_page, struct page *end_page, - int migratetype, int *num_movable) +static int __move_freepages_block(struct zone *zone, unsigned long start_pfn, + int old_mt, int new_mt) { struct page *page; + unsigned long pfn, end_pfn; unsigned int order; int pages_moved = 0; -#ifndef CONFIG_HOLES_IN_ZONE - /* - * page_zone is not safe to call in this context when - * CONFIG_HOLES_IN_ZONE is set. This bug check is probably redundant - * anyway as we check zone boundaries in move_freepages_block(). - * Remove at a later date when no bug reports exist related to - * grouping pages by mobility - */ - VM_BUG_ON(pfn_valid(page_to_pfn(start_page)) && - pfn_valid(page_to_pfn(end_page)) && - page_zone(start_page) != page_zone(end_page)); -#endif - for (page = start_page; page <= end_page;) { - if (!pfn_valid_within(page_to_pfn(page))) { - page++; + VM_WARN_ON(start_pfn & (pageblock_nr_pages - 1)); + end_pfn = pageblock_end_pfn(start_pfn); + + for (pfn = start_pfn; pfn < end_pfn;) { + page = pfn_to_page(pfn); + if (!PageBuddy(page)) { + pfn++; continue; } /* Make sure we are not inadvertently changing nodes */ VM_BUG_ON_PAGE(page_to_nid(page) != zone_to_nid(zone), page); + VM_BUG_ON_PAGE(page_zone(page) != zone, page); - if (!PageBuddy(page)) { + order = buddy_order(page); + + move_to_free_list(page, zone, order, old_mt, new_mt); + + pfn += 1 << order; + pages_moved += 1 << order; + } + + return pages_moved; +} + +static bool prep_move_freepages_block(struct zone *zone, struct page *page, + unsigned long *start_pfn, + int *num_free, int *num_movable) +{ + unsigned long pfn, start, end; + + pfn = page_to_pfn(page); + start = pageblock_start_pfn(pfn); + end = pageblock_end_pfn(pfn); + + /* + * The caller only has the lock for @zone, don't touch ranges + * that straddle into other zones. While we could move part of + * the range that's inside the zone, this call is usually + * accompanied by other operations such as migratetype updates + * which also should be locked. + */ + if (!zone_spans_pfn(zone, start)) + return false; + if (!zone_spans_pfn(zone, end - 1)) + return false; + + *start_pfn = start; + + if (num_free) { + *num_free = 0; + *num_movable = 0; + for (pfn = start; pfn < end;) { + page = pfn_to_page(pfn); + if (PageBuddy(page)) { + int nr = 1 << buddy_order(page); + + *num_free += nr; + pfn += nr; + continue; + } /* * We assume that pages that could be isolated for * migration are movable. But we don't actually try * isolating, as that would be expensive. */ - if (num_movable && - (PageLRU(page) || __PageMovable(page))) + if (PageLRU(page) || page_has_movable_ops(page)) (*num_movable)++; - - page++; - continue; + pfn++; } + } - order = page_order(page); - list_move(&page->lru, - &zone->free_area[order].free_list[migratetype]); - page += 1 << order; - pages_moved += 1 << order; + return true; +} + +static int move_freepages_block(struct zone *zone, struct page *page, + int old_mt, int new_mt) +{ + unsigned long start_pfn; + int res; + + if (!prep_move_freepages_block(zone, page, &start_pfn, NULL, NULL)) + return -1; + + res = __move_freepages_block(zone, start_pfn, old_mt, new_mt); + set_pageblock_migratetype(pfn_to_page(start_pfn), new_mt); + + return res; + +} + +#ifdef CONFIG_MEMORY_ISOLATION +/* Look for a buddy that straddles start_pfn */ +static unsigned long find_large_buddy(unsigned long start_pfn) +{ + /* + * If start_pfn is not an order-0 PageBuddy, next PageBuddy containing + * start_pfn has minimal order of __ffs(start_pfn) + 1. Start checking + * the order with __ffs(start_pfn). If start_pfn is order-0 PageBuddy, + * the starting order does not matter. + */ + int order = start_pfn ? __ffs(start_pfn) : MAX_PAGE_ORDER; + struct page *page; + unsigned long pfn = start_pfn; + + while (!PageBuddy(page = pfn_to_page(pfn))) { + /* Nothing found */ + if (++order > MAX_PAGE_ORDER) + return start_pfn; + pfn &= ~0UL << order; } - return pages_moved; + /* + * Found a preceding buddy, but does it straddle? + */ + if (pfn + (1 << buddy_order(page)) > start_pfn) + return pfn; + + /* Nothing found */ + return start_pfn; } -int move_freepages_block(struct zone *zone, struct page *page, - int migratetype, int *num_movable) +static inline void toggle_pageblock_isolate(struct page *page, bool isolate) { - unsigned long start_pfn, end_pfn; - struct page *start_page, *end_page; + if (isolate) + set_pageblock_isolate(page); + else + clear_pageblock_isolate(page); +} - if (num_movable) - *num_movable = 0; +/** + * __move_freepages_block_isolate - move free pages in block for page isolation + * @zone: the zone + * @page: the pageblock page + * @isolate: to isolate the given pageblock or unisolate it + * + * This is similar to move_freepages_block(), but handles the special + * case encountered in page isolation, where the block of interest + * might be part of a larger buddy spanning multiple pageblocks. + * + * Unlike the regular page allocator path, which moves pages while + * stealing buddies off the freelist, page isolation is interested in + * arbitrary pfn ranges that may have overlapping buddies on both ends. + * + * This function handles that. Straddling buddies are split into + * individual pageblocks. Only the block of interest is moved. + * + * Returns %true if pages could be moved, %false otherwise. + */ +static bool __move_freepages_block_isolate(struct zone *zone, + struct page *page, bool isolate) +{ + unsigned long start_pfn, buddy_pfn; + int from_mt; + int to_mt; + struct page *buddy; - start_pfn = page_to_pfn(page); - start_pfn = start_pfn & ~(pageblock_nr_pages-1); - start_page = pfn_to_page(start_pfn); - end_page = start_page + pageblock_nr_pages - 1; - end_pfn = start_pfn + pageblock_nr_pages - 1; + if (isolate == get_pageblock_isolate(page)) { + VM_WARN_ONCE(1, "%s a pageblock that is already in that state", + isolate ? "Isolate" : "Unisolate"); + return false; + } - /* Do not cross zone boundaries */ - if (!zone_spans_pfn(zone, start_pfn)) - start_page = page; - if (!zone_spans_pfn(zone, end_pfn)) - return 0; + if (!prep_move_freepages_block(zone, page, &start_pfn, NULL, NULL)) + return false; + + /* No splits needed if buddies can't span multiple blocks */ + if (pageblock_order == MAX_PAGE_ORDER) + goto move; - return move_freepages(zone, start_page, end_page, migratetype, - num_movable); + buddy_pfn = find_large_buddy(start_pfn); + buddy = pfn_to_page(buddy_pfn); + /* We're a part of a larger buddy */ + if (PageBuddy(buddy) && buddy_order(buddy) > pageblock_order) { + int order = buddy_order(buddy); + + del_page_from_free_list(buddy, zone, order, + get_pfnblock_migratetype(buddy, buddy_pfn)); + toggle_pageblock_isolate(page, isolate); + split_large_buddy(zone, buddy, buddy_pfn, order, FPI_NONE); + return true; + } + +move: + /* Use MIGRATETYPE_MASK to get non-isolate migratetype */ + if (isolate) { + from_mt = __get_pfnblock_flags_mask(page, page_to_pfn(page), + MIGRATETYPE_MASK); + to_mt = MIGRATE_ISOLATE; + } else { + from_mt = MIGRATE_ISOLATE; + to_mt = __get_pfnblock_flags_mask(page, page_to_pfn(page), + MIGRATETYPE_MASK); + } + + __move_freepages_block(zone, start_pfn, from_mt, to_mt); + toggle_pageblock_isolate(pfn_to_page(start_pfn), isolate); + + return true; } +bool pageblock_isolate_and_move_free_pages(struct zone *zone, struct page *page) +{ + return __move_freepages_block_isolate(zone, page, true); +} + +bool pageblock_unisolate_and_move_free_pages(struct zone *zone, struct page *page) +{ + return __move_freepages_block_isolate(zone, page, false); +} + +#endif /* CONFIG_MEMORY_ISOLATION */ + static void change_pageblock_range(struct page *pageblock_page, int start_order, int migratetype) { @@ -2128,83 +2158,141 @@ static void change_pageblock_range(struct page *pageblock_page, } } +static inline bool boost_watermark(struct zone *zone) +{ + unsigned long max_boost; + + if (!watermark_boost_factor) + return false; + /* + * Don't bother in zones that are unlikely to produce results. + * On small machines, including kdump capture kernels running + * in a small area, boosting the watermark can cause an out of + * memory situation immediately. + */ + if ((pageblock_nr_pages * 4) > zone_managed_pages(zone)) + return false; + + max_boost = mult_frac(zone->_watermark[WMARK_HIGH], + watermark_boost_factor, 10000); + + /* + * high watermark may be uninitialised if fragmentation occurs + * very early in boot so do not boost. We do not fall + * through and boost by pageblock_nr_pages as failing + * allocations that early means that reclaim is not going + * to help and it may even be impossible to reclaim the + * boosted watermark resulting in a hang. + */ + if (!max_boost) + return false; + + max_boost = max(pageblock_nr_pages, max_boost); + + zone->watermark_boost = min(zone->watermark_boost + pageblock_nr_pages, + max_boost); + + return true; +} + /* - * When we are falling back to another migratetype during allocation, try to - * steal extra free pages from the same pageblocks to satisfy further - * allocations, instead of polluting multiple pageblocks. - * - * If we are stealing a relatively large buddy page, it is likely there will - * be more free pages in the pageblock, so try to steal them all. For - * reclaimable and unmovable allocations, we steal regardless of page size, - * as fragmentation caused by those allocations polluting movable pageblocks - * is worse than movable allocations stealing from unmovable and reclaimable - * pageblocks. + * When we are falling back to another migratetype during allocation, should we + * try to claim an entire block to satisfy further allocations, instead of + * polluting multiple pageblocks? */ -static bool can_steal_fallback(unsigned int order, int start_mt) +static bool should_try_claim_block(unsigned int order, int start_mt) { /* * Leaving this order check is intended, although there is * relaxed order check in next check. The reason is that - * we can actually steal whole pageblock if this condition met, + * we can actually claim the whole pageblock if this condition met, * but, below check doesn't guarantee it and that is just heuristic * so could be changed anytime. */ if (order >= pageblock_order) return true; - if (order >= pageblock_order / 2 || - start_mt == MIGRATE_RECLAIMABLE || - start_mt == MIGRATE_UNMOVABLE || - page_group_by_mobility_disabled) + /* + * Above a certain threshold, always try to claim, as it's likely there + * will be more free pages in the pageblock. + */ + if (order >= pageblock_order / 2) + return true; + + /* + * Unmovable/reclaimable allocations would cause permanent + * fragmentations if they fell back to allocating from a movable block + * (polluting it), so we try to claim the whole block regardless of the + * allocation size. Later movable allocations can always steal from this + * block, which is less problematic. + */ + if (start_mt == MIGRATE_RECLAIMABLE || start_mt == MIGRATE_UNMOVABLE) + return true; + + if (page_group_by_mobility_disabled) return true; + /* + * Movable pages won't cause permanent fragmentation, so when you alloc + * small pages, we just need to temporarily steal unmovable or + * reclaimable pages that are closest to the request size. After a + * while, memory compaction may occur to form large contiguous pages, + * and the next movable allocation may not need to steal. + */ return false; } -static inline void boost_watermark(struct zone *zone) +/* + * Check whether there is a suitable fallback freepage with requested order. + * If claimable is true, this function returns fallback_mt only if + * we would do this whole-block claiming. This would help to reduce + * fragmentation due to mixed migratetype pages in one pageblock. + */ +int find_suitable_fallback(struct free_area *area, unsigned int order, + int migratetype, bool claimable) { - unsigned long max_boost; + int i; - if (!watermark_boost_factor) - return; + if (claimable && !should_try_claim_block(order, migratetype)) + return -2; - max_boost = mult_frac(zone->_watermark[WMARK_HIGH], - watermark_boost_factor, 10000); - max_boost = max(pageblock_nr_pages, max_boost); + if (area->nr_free == 0) + return -1; - zone->watermark_boost = min(zone->watermark_boost + pageblock_nr_pages, - max_boost); + for (i = 0; i < MIGRATE_PCPTYPES - 1 ; i++) { + int fallback_mt = fallbacks[migratetype][i]; + + if (!free_area_empty(area, fallback_mt)) + return fallback_mt; + } + + return -1; } /* - * This function implements actual steal behaviour. If order is large enough, - * we can steal whole pageblock. If not, we first move freepages in this - * pageblock to our migratetype and determine how many already-allocated pages - * are there in the pageblock with a compatible migratetype. If at least half - * of pages are free or compatible, we can change migratetype of the pageblock - * itself, so pages freed in the future will be put on the correct free list. + * This function implements actual block claiming behaviour. If order is large + * enough, we can claim the whole pageblock for the requested migratetype. If + * not, we check the pageblock for constituent pages; if at least half of the + * pages are free or compatible, we can still claim the whole block, so pages + * freed in the future will be put on the correct free list. */ -static void steal_suitable_fallback(struct zone *zone, struct page *page, - unsigned int alloc_flags, int start_type, bool whole_block) +static struct page * +try_to_claim_block(struct zone *zone, struct page *page, + int current_order, int order, int start_type, + int block_type, unsigned int alloc_flags) { - unsigned int current_order = page_order(page); - struct free_area *area; int free_pages, movable_pages, alike_pages; - int old_block_type; - - old_block_type = get_pageblock_migratetype(page); - - /* - * This can happen due to races and we want to prevent broken - * highatomic accounting. - */ - if (is_migrate_highatomic(old_block_type)) - goto single_page; + unsigned long start_pfn; /* Take ownership for orders >= pageblock_order */ if (current_order >= pageblock_order) { + unsigned int nr_added; + + del_page_from_free_list(page, zone, current_order, block_type); change_pageblock_range(page, current_order, start_type); - goto single_page; + nr_added = expand(zone, page, order, current_order, start_type); + account_freepages(zone, nr_added, start_type); + return page; } /* @@ -2212,16 +2300,14 @@ static void steal_suitable_fallback(struct zone *zone, struct page *page, * likelihood of future fallbacks. Wake kswapd now as the node * may be balanced overall and kswapd will not wake naturally. */ - boost_watermark(zone); - if (alloc_flags & ALLOC_KSWAPD) + if (boost_watermark(zone) && (alloc_flags & ALLOC_KSWAPD)) set_bit(ZONE_BOOSTED_WATERMARK, &zone->flags); - /* We are not allowed to try stealing from the whole block */ - if (!whole_block) - goto single_page; + /* moving whole block can fail due to zone boundary conditions */ + if (!prep_move_freepages_block(zone, page, &start_pfn, &free_pages, + &movable_pages)) + return NULL; - free_pages = move_freepages_block(zone, page, start_type, - &movable_pages); /* * Determine how many pages are compatible with our allocation. * For movable allocation, it's the number of movable pages which @@ -2237,201 +2323,36 @@ static void steal_suitable_fallback(struct zone *zone, struct page *page, * vice versa, be conservative since we can't distinguish the * exact migratetype of non-movable pages. */ - if (old_block_type == MIGRATE_MOVABLE) + if (block_type == MIGRATE_MOVABLE) alike_pages = pageblock_nr_pages - (free_pages + movable_pages); else alike_pages = 0; } - - /* moving whole block can fail due to zone boundary conditions */ - if (!free_pages) - goto single_page; - /* * If a sufficient number of pages in the block are either free or of - * comparable migratability as our allocation, claim the whole block. + * compatible migratability as our allocation, claim the whole block. */ if (free_pages + alike_pages >= (1 << (pageblock_order-1)) || - page_group_by_mobility_disabled) - set_pageblock_migratetype(page, start_type); - - return; - -single_page: - area = &zone->free_area[current_order]; - list_move(&page->lru, &area->free_list[start_type]); -} - -/* - * Check whether there is a suitable fallback freepage with requested order. - * If only_stealable is true, this function returns fallback_mt only if - * we can steal other freepages all together. This would help to reduce - * fragmentation due to mixed migratetype pages in one pageblock. - */ -int find_suitable_fallback(struct free_area *area, unsigned int order, - int migratetype, bool only_stealable, bool *can_steal) -{ - int i; - int fallback_mt; - - if (area->nr_free == 0) - return -1; - - *can_steal = false; - for (i = 0;; i++) { - fallback_mt = fallbacks[migratetype][i]; - if (fallback_mt == MIGRATE_TYPES) - break; - - if (list_empty(&area->free_list[fallback_mt])) - continue; - - if (can_steal_fallback(order, migratetype)) - *can_steal = true; - - if (!only_stealable) - return fallback_mt; - - if (*can_steal) - return fallback_mt; - } - - return -1; -} - -/* - * Reserve a pageblock for exclusive use of high-order atomic allocations if - * there are no empty page blocks that contain a page with a suitable order - */ -static void reserve_highatomic_pageblock(struct page *page, struct zone *zone, - unsigned int alloc_order) -{ - int mt; - unsigned long max_managed, flags; - - /* - * Limit the number reserved to 1 pageblock or roughly 1% of a zone. - * Check is race-prone but harmless. - */ - max_managed = (zone_managed_pages(zone) / 100) + pageblock_nr_pages; - if (zone->nr_reserved_highatomic >= max_managed) - return; - - spin_lock_irqsave(&zone->lock, flags); - - /* Recheck the nr_reserved_highatomic limit under the lock */ - if (zone->nr_reserved_highatomic >= max_managed) - goto out_unlock; - - /* Yoink! */ - mt = get_pageblock_migratetype(page); - if (!is_migrate_highatomic(mt) && !is_migrate_isolate(mt) - && !is_migrate_cma(mt)) { - zone->nr_reserved_highatomic += pageblock_nr_pages; - set_pageblock_migratetype(page, MIGRATE_HIGHATOMIC); - move_freepages_block(zone, page, MIGRATE_HIGHATOMIC, NULL); - } - -out_unlock: - spin_unlock_irqrestore(&zone->lock, flags); -} - -/* - * Used when an allocation is about to fail under memory pressure. This - * potentially hurts the reliability of high-order allocations when under - * intense memory pressure but failed atomic allocations should be easier - * to recover from than an OOM. - * - * If @force is true, try to unreserve a pageblock even though highatomic - * pageblock is exhausted. - */ -static bool unreserve_highatomic_pageblock(const struct alloc_context *ac, - bool force) -{ - struct zonelist *zonelist = ac->zonelist; - unsigned long flags; - struct zoneref *z; - struct zone *zone; - struct page *page; - int order; - bool ret; - - for_each_zone_zonelist_nodemask(zone, z, zonelist, ac->high_zoneidx, - ac->nodemask) { - /* - * Preserve at least one pageblock unless memory pressure - * is really high. - */ - if (!force && zone->nr_reserved_highatomic <= - pageblock_nr_pages) - continue; - - spin_lock_irqsave(&zone->lock, flags); - for (order = 0; order < MAX_ORDER; order++) { - struct free_area *area = &(zone->free_area[order]); - - page = list_first_entry_or_null( - &area->free_list[MIGRATE_HIGHATOMIC], - struct page, lru); - if (!page) - continue; - - /* - * In page freeing path, migratetype change is racy so - * we can counter several free pages in a pageblock - * in this loop althoug we changed the pageblock type - * from highatomic to ac->migratetype. So we should - * adjust the count once. - */ - if (is_migrate_highatomic_page(page)) { - /* - * It should never happen but changes to - * locking could inadvertently allow a per-cpu - * drain to add pages to MIGRATE_HIGHATOMIC - * while unreserving so be safe and watch for - * underflows. - */ - zone->nr_reserved_highatomic -= min( - pageblock_nr_pages, - zone->nr_reserved_highatomic); - } - - /* - * Convert to ac->migratetype and avoid the normal - * pageblock stealing heuristics. Minimally, the caller - * is doing the work and needs the pages. More - * importantly, if the block was always converted to - * MIGRATE_UNMOVABLE or another type then the number - * of pageblocks that cannot be completely freed - * may increase. - */ - set_pageblock_migratetype(page, ac->migratetype); - ret = move_freepages_block(zone, page, ac->migratetype, - NULL); - if (ret) { - spin_unlock_irqrestore(&zone->lock, flags); - return ret; - } - } - spin_unlock_irqrestore(&zone->lock, flags); + page_group_by_mobility_disabled) { + __move_freepages_block(zone, start_pfn, block_type, start_type); + set_pageblock_migratetype(pfn_to_page(start_pfn), start_type); + return __rmqueue_smallest(zone, order, start_type); } - return false; + return NULL; } /* - * Try finding a free buddy page on the fallback list and put it on the free - * list of requested migratetype, possibly along with other pages from the same - * block, depending on fragmentation avoidance heuristics. Returns true if - * fallback was found so that __rmqueue_smallest() can grab it. + * Try to allocate from some fallback migratetype by claiming the entire block, + * i.e. converting it to the allocation's start migratetype. * * The use of signed ints for order and current_order is a deliberate * deviation from the rest of this file, to make the for loop * condition simpler. */ -static __always_inline bool -__rmqueue_fallback(struct zone *zone, int order, int start_migratetype, +static __always_inline struct page * +__rmqueue_claim(struct zone *zone, int order, int start_migratetype, unsigned int alloc_flags) { struct free_area *area; @@ -2439,14 +2360,13 @@ __rmqueue_fallback(struct zone *zone, int order, int start_migratetype, int min_order = order; struct page *page; int fallback_mt; - bool can_steal; /* * Do not steal pages from freelists belonging to other pageblocks * i.e. orders < pageblock_order. If there are no local zones free, * the zonelists will be reiterated without ALLOC_NOFRAGMENT. */ - if (alloc_flags & ALLOC_NOFRAGMENT) + if (order < pageblock_order && alloc_flags & ALLOC_NOFRAGMENT) min_order = pageblock_order; /* @@ -2454,84 +2374,137 @@ __rmqueue_fallback(struct zone *zone, int order, int start_migratetype, * approximates finding the pageblock with the most free pages, which * would be too costly to do exactly. */ - for (current_order = MAX_ORDER - 1; current_order >= min_order; + for (current_order = MAX_PAGE_ORDER; current_order >= min_order; --current_order) { area = &(zone->free_area[current_order]); fallback_mt = find_suitable_fallback(area, current_order, - start_migratetype, false, &can_steal); + start_migratetype, true); + + /* No block in that order */ if (fallback_mt == -1) continue; - /* - * We cannot steal all free pages from the pageblock and the - * requested migratetype is movable. In that case it's better to - * steal and split the smallest available page instead of the - * largest available page, because even if the next movable - * allocation falls back into a different pageblock than this - * one, it won't cause permanent fragmentation. - */ - if (!can_steal && start_migratetype == MIGRATE_MOVABLE - && current_order > order) - goto find_smallest; + /* Advanced into orders too low to claim, abort */ + if (fallback_mt == -2) + break; - goto do_steal; + page = get_page_from_free_area(area, fallback_mt); + page = try_to_claim_block(zone, page, current_order, order, + start_migratetype, fallback_mt, + alloc_flags); + if (page) { + trace_mm_page_alloc_extfrag(page, order, current_order, + start_migratetype, fallback_mt); + return page; + } } - return false; + return NULL; +} + +/* + * Try to steal a single page from some fallback migratetype. Leave the rest of + * the block as its current migratetype, potentially causing fragmentation. + */ +static __always_inline struct page * +__rmqueue_steal(struct zone *zone, int order, int start_migratetype) +{ + struct free_area *area; + int current_order; + struct page *page; + int fallback_mt; -find_smallest: - for (current_order = order; current_order < MAX_ORDER; - current_order++) { + for (current_order = order; current_order < NR_PAGE_ORDERS; current_order++) { area = &(zone->free_area[current_order]); fallback_mt = find_suitable_fallback(area, current_order, - start_migratetype, false, &can_steal); - if (fallback_mt != -1) - break; - } - - /* - * This should not happen - we already found a suitable fallback - * when looking for the largest page. - */ - VM_BUG_ON(current_order == MAX_ORDER); - -do_steal: - page = list_first_entry(&area->free_list[fallback_mt], - struct page, lru); - - steal_suitable_fallback(zone, page, alloc_flags, start_migratetype, - can_steal); - - trace_mm_page_alloc_extfrag(page, order, current_order, - start_migratetype, fallback_mt); + start_migratetype, false); + if (fallback_mt == -1) + continue; - return true; + page = get_page_from_free_area(area, fallback_mt); + page_del_and_expand(zone, page, order, current_order, fallback_mt); + trace_mm_page_alloc_extfrag(page, order, current_order, + start_migratetype, fallback_mt); + return page; + } + return NULL; } +enum rmqueue_mode { + RMQUEUE_NORMAL, + RMQUEUE_CMA, + RMQUEUE_CLAIM, + RMQUEUE_STEAL, +}; + /* * Do the hard work of removing an element from the buddy allocator. * Call me with the zone->lock already held. */ static __always_inline struct page * __rmqueue(struct zone *zone, unsigned int order, int migratetype, - unsigned int alloc_flags) + unsigned int alloc_flags, enum rmqueue_mode *mode) { struct page *page; -retry: - page = __rmqueue_smallest(zone, order, migratetype); - if (unlikely(!page)) { - if (migratetype == MIGRATE_MOVABLE) + if (IS_ENABLED(CONFIG_CMA)) { + /* + * Balance movable allocations between regular and CMA areas by + * allocating from CMA when over half of the zone's free memory + * is in the CMA area. + */ + if (alloc_flags & ALLOC_CMA && + zone_page_state(zone, NR_FREE_CMA_PAGES) > + zone_page_state(zone, NR_FREE_PAGES) / 2) { page = __rmqueue_cma_fallback(zone, order); - - if (!page && __rmqueue_fallback(zone, order, migratetype, - alloc_flags)) - goto retry; + if (page) + return page; + } } - trace_mm_page_alloc_zone_locked(page, order, migratetype); - return page; + /* + * First try the freelists of the requested migratetype, then try + * fallbacks modes with increasing levels of fragmentation risk. + * + * The fallback logic is expensive and rmqueue_bulk() calls in + * a loop with the zone->lock held, meaning the freelists are + * not subject to any outside changes. Remember in *mode where + * we found pay dirt, to save us the search on the next call. + */ + switch (*mode) { + case RMQUEUE_NORMAL: + page = __rmqueue_smallest(zone, order, migratetype); + if (page) + return page; + fallthrough; + case RMQUEUE_CMA: + if (alloc_flags & ALLOC_CMA) { + page = __rmqueue_cma_fallback(zone, order); + if (page) { + *mode = RMQUEUE_CMA; + return page; + } + } + fallthrough; + case RMQUEUE_CLAIM: + page = __rmqueue_claim(zone, order, migratetype, alloc_flags); + if (page) { + /* Replenished preferred freelist, back to normal mode. */ + *mode = RMQUEUE_NORMAL; + return page; + } + fallthrough; + case RMQUEUE_STEAL: + if (!(alloc_flags & ALLOC_NOFRAGMENT)) { + page = __rmqueue_steal(zone, order, migratetype); + if (page) { + *mode = RMQUEUE_STEAL; + return page; + } + } + } + return NULL; } /* @@ -2543,18 +2516,22 @@ static int rmqueue_bulk(struct zone *zone, unsigned int order, unsigned long count, struct list_head *list, int migratetype, unsigned int alloc_flags) { - int i, alloced = 0; + enum rmqueue_mode rmqm = RMQUEUE_NORMAL; + unsigned long flags; + int i; - spin_lock(&zone->lock); + if (unlikely(alloc_flags & ALLOC_TRYLOCK)) { + if (!spin_trylock_irqsave(&zone->lock, flags)) + return 0; + } else { + spin_lock_irqsave(&zone->lock, flags); + } for (i = 0; i < count; ++i) { struct page *page = __rmqueue(zone, order, migratetype, - alloc_flags); + alloc_flags, &rmqm); if (unlikely(page == NULL)) break; - if (unlikely(check_pcp_refill(page))) - continue; - /* * Split buddy pages returned by expand() are received here in * physical page order. The page is added to the tail of @@ -2565,22 +2542,48 @@ static int rmqueue_bulk(struct zone *zone, unsigned int order, * for IO devices that can merge IO requests if the physical * pages are ordered properly. */ - list_add_tail(&page->lru, list); - alloced++; - if (is_migrate_cma(get_pcppage_migratetype(page))) - __mod_zone_page_state(zone, NR_FREE_CMA_PAGES, - -(1 << order)); + list_add_tail(&page->pcp_list, list); } + spin_unlock_irqrestore(&zone->lock, flags); + return i; +} + +/* + * Called from the vmstat counter updater to decay the PCP high. + * Return whether there are addition works to do. + */ +bool decay_pcp_high(struct zone *zone, struct per_cpu_pages *pcp) +{ + int high_min, to_drain, to_drain_batched, batch; + bool todo = false; + + high_min = READ_ONCE(pcp->high_min); + batch = READ_ONCE(pcp->batch); /* - * i pages were removed from the buddy list even if some leak due - * to check_pcp_refill failing so adjust NR_FREE_PAGES based - * on i. Do not confuse with 'alloced' which is the number of - * pages added to the pcp list. + * Decrease pcp->high periodically to try to free possible + * idle PCP pages. And, avoid to free too many pages to + * control latency. This caps pcp->high decrement too. */ - __mod_zone_page_state(zone, NR_FREE_PAGES, -(i << order)); - spin_unlock(&zone->lock); - return alloced; + if (pcp->high > high_min) { + pcp->high = max3(pcp->count - (batch << CONFIG_PCP_BATCH_SCALE_MAX), + pcp->high - (pcp->high >> 3), high_min); + if (pcp->high > high_min) + todo = true; + } + + to_drain = pcp->count - pcp->high; + while (to_drain > 0) { + to_drain_batched = min(to_drain, batch); + spin_lock(&pcp->lock); + free_pcppages_bulk(zone, to_drain_batched, pcp, 0); + spin_unlock(&pcp->lock); + todo = true; + + to_drain -= to_drain_batched; + } + + return todo; } #ifdef CONFIG_NUMA @@ -2588,52 +2591,45 @@ static int rmqueue_bulk(struct zone *zone, unsigned int order, * Called from the vmstat counter updater to drain pagesets of this * currently executing processor on remote nodes after they have * expired. - * - * Note that this function must be called with the thread pinned to - * a single processor. */ void drain_zone_pages(struct zone *zone, struct per_cpu_pages *pcp) { - unsigned long flags; int to_drain, batch; - local_irq_save(flags); batch = READ_ONCE(pcp->batch); to_drain = min(pcp->count, batch); - if (to_drain > 0) - free_pcppages_bulk(zone, to_drain, pcp); - local_irq_restore(flags); + if (to_drain > 0) { + spin_lock(&pcp->lock); + free_pcppages_bulk(zone, to_drain, pcp, 0); + spin_unlock(&pcp->lock); + } } #endif /* * Drain pcplists of the indicated processor and zone. - * - * The processor must either be the current processor and the - * thread pinned to the current processor or a processor that - * is not online. */ static void drain_pages_zone(unsigned int cpu, struct zone *zone) { - unsigned long flags; - struct per_cpu_pageset *pset; - struct per_cpu_pages *pcp; - - local_irq_save(flags); - pset = per_cpu_ptr(zone->pageset, cpu); + struct per_cpu_pages *pcp = per_cpu_ptr(zone->per_cpu_pageset, cpu); + int count; - pcp = &pset->pcp; - if (pcp->count) - free_pcppages_bulk(zone, pcp->count, pcp); - local_irq_restore(flags); + do { + spin_lock(&pcp->lock); + count = pcp->count; + if (count) { + int to_drain = min(count, + pcp->batch << CONFIG_PCP_BATCH_SCALE_MAX); + + free_pcppages_bulk(zone, to_drain, pcp, 0); + count -= to_drain; + } + spin_unlock(&pcp->lock); + } while (count); } /* * Drain pcplists of all zones on the indicated processor. - * - * The processor must either be the current processor and the - * thread pinned to the current processor or a processor that - * is not online. */ static void drain_pages(unsigned int cpu) { @@ -2646,9 +2642,6 @@ static void drain_pages(unsigned int cpu) /* * Spill all of this CPU's per-cpu pages back into the buddy allocator. - * - * The CPU has to be pinned. When zone parameter is non-NULL, spill just - * the single zone's pages. */ void drain_local_pages(struct zone *zone) { @@ -2660,49 +2653,27 @@ void drain_local_pages(struct zone *zone) drain_pages(cpu); } -static void drain_local_pages_wq(struct work_struct *work) -{ - struct pcpu_drain *drain; - - drain = container_of(work, struct pcpu_drain, work); - - /* - * drain_all_pages doesn't use proper cpu hotplug protection so - * we can race with cpu offline when the WQ can move this from - * a cpu pinned worker to an unbound one. We can operate on a different - * cpu which is allright but we also have to make sure to not move to - * a different one. - */ - preempt_disable(); - drain_local_pages(drain->zone); - preempt_enable(); -} - /* - * Spill all the per-cpu pages from all CPUs back into the buddy allocator. + * The implementation of drain_all_pages(), exposing an extra parameter to + * drain on all cpus. * - * When zone parameter is non-NULL, spill just the single zone's pages. - * - * Note that this can be extremely slow as the draining happens in a workqueue. + * drain_all_pages() is optimized to only execute on cpus where pcplists are + * not empty. The check for non-emptiness can however race with a free to + * pcplist that has not yet increased the pcp->count from 0 to 1. Callers + * that need the guarantee that every CPU has drained can disable the + * optimizing racy check. */ -void drain_all_pages(struct zone *zone) +static void __drain_all_pages(struct zone *zone, bool force_all_cpus) { int cpu; /* - * Allocate in the BSS so we wont require allocation in + * Allocate in the BSS so we won't require allocation in * direct reclaim path for CONFIG_CPUMASK_OFFSTACK=y */ static cpumask_t cpus_with_pcps; /* - * Make sure nobody triggers this path before mm_percpu_wq is fully - * initialized. - */ - if (WARN_ON_ONCE(!mm_percpu_wq)) - return; - - /* * Do not drain if one is already in progress unless it's specific to * a zone. Such callers are primarily CMA and memory hotplug and need * the drain to be complete when the call returns. @@ -2720,18 +2691,24 @@ void drain_all_pages(struct zone *zone) * disables preemption as part of its processing */ for_each_online_cpu(cpu) { - struct per_cpu_pageset *pcp; + struct per_cpu_pages *pcp; struct zone *z; bool has_pcps = false; - if (zone) { - pcp = per_cpu_ptr(zone->pageset, cpu); - if (pcp->pcp.count) + if (force_all_cpus) { + /* + * The pcp.count check is racy, some callers need a + * guarantee that no cpu is missed. + */ + has_pcps = true; + } else if (zone) { + pcp = per_cpu_ptr(zone->per_cpu_pageset, cpu); + if (pcp->count) has_pcps = true; } else { for_each_populated_zone(z) { - pcp = per_cpu_ptr(z->pageset, cpu); - if (pcp->pcp.count) { + pcp = per_cpu_ptr(z->per_cpu_pageset, cpu); + if (pcp->count) { has_pcps = true; break; } @@ -2745,170 +2722,359 @@ void drain_all_pages(struct zone *zone) } for_each_cpu(cpu, &cpus_with_pcps) { - struct pcpu_drain *drain = per_cpu_ptr(&pcpu_drain, cpu); - - drain->zone = zone; - INIT_WORK(&drain->work, drain_local_pages_wq); - queue_work_on(cpu, mm_percpu_wq, &drain->work); + if (zone) + drain_pages_zone(cpu, zone); + else + drain_pages(cpu); } - for_each_cpu(cpu, &cpus_with_pcps) - flush_work(&per_cpu_ptr(&pcpu_drain, cpu)->work); mutex_unlock(&pcpu_drain_mutex); } -#ifdef CONFIG_HIBERNATION - /* - * Touch the watchdog for every WD_PAGE_COUNT pages. + * Spill all the per-cpu pages from all CPUs back into the buddy allocator. + * + * When zone parameter is non-NULL, spill just the single zone's pages. */ -#define WD_PAGE_COUNT (128*1024) +void drain_all_pages(struct zone *zone) +{ + __drain_all_pages(zone, false); +} -void mark_free_pages(struct zone *zone) +static int nr_pcp_free(struct per_cpu_pages *pcp, int batch, int high, bool free_high) { - unsigned long pfn, max_zone_pfn, page_count = WD_PAGE_COUNT; - unsigned long flags; - unsigned int order, t; - struct page *page; + int min_nr_free, max_nr_free; - if (zone_is_empty(zone)) - return; + /* Free as much as possible if batch freeing high-order pages. */ + if (unlikely(free_high)) + return min(pcp->count, batch << CONFIG_PCP_BATCH_SCALE_MAX); - spin_lock_irqsave(&zone->lock, flags); + /* Check for PCP disabled or boot pageset */ + if (unlikely(high < batch)) + return 1; - max_zone_pfn = zone_end_pfn(zone); - for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) - if (pfn_valid(pfn)) { - page = pfn_to_page(pfn); + /* Leave at least pcp->batch pages on the list */ + min_nr_free = batch; + max_nr_free = high - batch; - if (!--page_count) { - touch_nmi_watchdog(); - page_count = WD_PAGE_COUNT; - } + /* + * Increase the batch number to the number of the consecutive + * freed pages to reduce zone lock contention. + */ + batch = clamp_t(int, pcp->free_count, min_nr_free, max_nr_free); - if (page_zone(page) != zone) - continue; + return batch; +} - if (!swsusp_page_is_forbidden(page)) - swsusp_unset_page_free(page); - } +static int nr_pcp_high(struct per_cpu_pages *pcp, struct zone *zone, + int batch, bool free_high) +{ + int high, high_min, high_max; - for_each_migratetype_order(order, t) { - list_for_each_entry(page, - &zone->free_area[order].free_list[t], lru) { - unsigned long i; + high_min = READ_ONCE(pcp->high_min); + high_max = READ_ONCE(pcp->high_max); + high = pcp->high = clamp(pcp->high, high_min, high_max); - pfn = page_to_pfn(page); - for (i = 0; i < (1UL << order); i++) { - if (!--page_count) { - touch_nmi_watchdog(); - page_count = WD_PAGE_COUNT; - } - swsusp_set_page_free(pfn_to_page(pfn + i)); - } - } + if (unlikely(!high)) + return 0; + + if (unlikely(free_high)) { + pcp->high = max(high - (batch << CONFIG_PCP_BATCH_SCALE_MAX), + high_min); + return 0; } - spin_unlock_irqrestore(&zone->lock, flags); + + /* + * If reclaim is active, limit the number of pages that can be + * stored on pcp lists + */ + if (test_bit(ZONE_RECLAIM_ACTIVE, &zone->flags)) { + int free_count = max_t(int, pcp->free_count, batch); + + pcp->high = max(high - free_count, high_min); + return min(batch << 2, pcp->high); + } + + if (high_min == high_max) + return high; + + if (test_bit(ZONE_BELOW_HIGH, &zone->flags)) { + int free_count = max_t(int, pcp->free_count, batch); + + pcp->high = max(high - free_count, high_min); + high = max(pcp->count, high_min); + } else if (pcp->count >= high) { + int need_high = pcp->free_count + batch; + + /* pcp->high should be large enough to hold batch freed pages */ + if (pcp->high < need_high) + pcp->high = clamp(need_high, high_min, high_max); + } + + return high; } -#endif /* CONFIG_PM */ -static bool free_unref_page_prepare(struct page *page, unsigned long pfn) +/* + * Tune pcp alloc factor and adjust count & free_count. Free pages to bring the + * pcp's watermarks below high. + * + * May return a freed pcp, if during page freeing the pcp spinlock cannot be + * reacquired. Return true if pcp is locked, false otherwise. + */ +static bool free_frozen_page_commit(struct zone *zone, + struct per_cpu_pages *pcp, struct page *page, int migratetype, + unsigned int order, fpi_t fpi_flags, unsigned long *UP_flags) { - int migratetype; + int high, batch; + int to_free, to_free_batched; + int pindex; + int cpu = smp_processor_id(); + int ret = true; + bool free_high = false; - if (!free_pcp_prepare(page)) - return false; + /* + * On freeing, reduce the number of pages that are batch allocated. + * See nr_pcp_alloc() where alloc_factor is increased for subsequent + * allocations. + */ + pcp->alloc_factor >>= 1; + __count_vm_events(PGFREE, 1 << order); + pindex = order_to_pindex(migratetype, order); + list_add(&page->pcp_list, &pcp->lists[pindex]); + pcp->count += 1 << order; - migratetype = get_pfnblock_migratetype(page, pfn); - set_pcppage_migratetype(page, migratetype); - return true; + batch = READ_ONCE(pcp->batch); + /* + * As high-order pages other than THP's stored on PCP can contribute + * to fragmentation, limit the number stored when PCP is heavily + * freeing without allocation. The remainder after bulk freeing + * stops will be drained from vmstat refresh context. + */ + if (order && order <= PAGE_ALLOC_COSTLY_ORDER) { + free_high = (pcp->free_count >= (batch + pcp->high_min / 2) && + (pcp->flags & PCPF_PREV_FREE_HIGH_ORDER) && + (!(pcp->flags & PCPF_FREE_HIGH_BATCH) || + pcp->count >= batch)); + pcp->flags |= PCPF_PREV_FREE_HIGH_ORDER; + } else if (pcp->flags & PCPF_PREV_FREE_HIGH_ORDER) { + pcp->flags &= ~PCPF_PREV_FREE_HIGH_ORDER; + } + if (pcp->free_count < (batch << CONFIG_PCP_BATCH_SCALE_MAX)) + pcp->free_count += (1 << order); + + if (unlikely(fpi_flags & FPI_TRYLOCK)) { + /* + * Do not attempt to take a zone lock. Let pcp->count get + * over high mark temporarily. + */ + return true; + } + + high = nr_pcp_high(pcp, zone, batch, free_high); + if (pcp->count < high) + return true; + + to_free = nr_pcp_free(pcp, batch, high, free_high); + while (to_free > 0 && pcp->count > 0) { + to_free_batched = min(to_free, batch); + free_pcppages_bulk(zone, to_free_batched, pcp, pindex); + to_free -= to_free_batched; + + if (to_free == 0 || pcp->count == 0) + break; + + pcp_spin_unlock(pcp, *UP_flags); + + pcp = pcp_spin_trylock(zone->per_cpu_pageset, *UP_flags); + if (!pcp) { + ret = false; + break; + } + + /* + * Check if this thread has been migrated to a different CPU. + * If that is the case, give up and indicate that the pcp is + * returned in an unlocked state. + */ + if (smp_processor_id() != cpu) { + pcp_spin_unlock(pcp, *UP_flags); + ret = false; + break; + } + } + + if (test_bit(ZONE_BELOW_HIGH, &zone->flags) && + zone_watermark_ok(zone, 0, high_wmark_pages(zone), + ZONE_MOVABLE, 0)) { + struct pglist_data *pgdat = zone->zone_pgdat; + clear_bit(ZONE_BELOW_HIGH, &zone->flags); + + /* + * Assume that memory pressure on this node is gone and may be + * in a reclaimable state. If a memory fallback node exists, + * direct reclaim may not have been triggered, causing a + * 'hopeless node' to stay in that state for a while. Let + * kswapd work again by resetting kswapd_failures. + */ + if (atomic_read(&pgdat->kswapd_failures) >= MAX_RECLAIM_RETRIES && + next_memory_node(pgdat->node_id) < MAX_NUMNODES) + atomic_set(&pgdat->kswapd_failures, 0); + } + return ret; } -static void free_unref_page_commit(struct page *page, unsigned long pfn) +/* + * Free a pcp page + */ +static void __free_frozen_pages(struct page *page, unsigned int order, + fpi_t fpi_flags) { - struct zone *zone = page_zone(page); + unsigned long UP_flags; struct per_cpu_pages *pcp; + struct zone *zone; + unsigned long pfn = page_to_pfn(page); int migratetype; - migratetype = get_pcppage_migratetype(page); - __count_vm_event(PGFREE); + if (!pcp_allowed_order(order)) { + __free_pages_ok(page, order, fpi_flags); + return; + } + + if (!free_pages_prepare(page, order)) + return; /* * We only track unmovable, reclaimable and movable on pcp lists. - * Free ISOLATE pages back to the allocator because they are being - * offlined but treat HIGHATOMIC as movable pages so we can get those - * areas back if necessary. Otherwise, we may have to free + * Place ISOLATE pages on the isolated list because they are being + * offlined but treat HIGHATOMIC and CMA as movable pages so we can + * get those areas back if necessary. Otherwise, we may have to free * excessively into the page allocator */ - if (migratetype >= MIGRATE_PCPTYPES) { + zone = page_zone(page); + migratetype = get_pfnblock_migratetype(page, pfn); + if (unlikely(migratetype >= MIGRATE_PCPTYPES)) { if (unlikely(is_migrate_isolate(migratetype))) { - free_one_page(zone, page, pfn, 0, migratetype); + free_one_page(zone, page, pfn, order, fpi_flags); return; } migratetype = MIGRATE_MOVABLE; } - pcp = &this_cpu_ptr(zone->pageset)->pcp; - list_add(&page->lru, &pcp->lists[migratetype]); - pcp->count++; - if (pcp->count >= pcp->high) { - unsigned long batch = READ_ONCE(pcp->batch); - free_pcppages_bulk(zone, batch, pcp); + if (unlikely((fpi_flags & FPI_TRYLOCK) && IS_ENABLED(CONFIG_PREEMPT_RT) + && (in_nmi() || in_hardirq()))) { + add_page_to_zone_llist(zone, page, order); + return; + } + pcp = pcp_spin_trylock(zone->per_cpu_pageset, UP_flags); + if (pcp) { + if (!free_frozen_page_commit(zone, pcp, page, migratetype, + order, fpi_flags, &UP_flags)) + return; + pcp_spin_unlock(pcp, UP_flags); + } else { + free_one_page(zone, page, pfn, order, fpi_flags); } } -/* - * Free a 0-order page - */ -void free_unref_page(struct page *page) +void free_frozen_pages(struct page *page, unsigned int order) { - unsigned long flags; - unsigned long pfn = page_to_pfn(page); - - if (!free_unref_page_prepare(page, pfn)) - return; - - local_irq_save(flags); - free_unref_page_commit(page, pfn); - local_irq_restore(flags); + __free_frozen_pages(page, order, FPI_NONE); } /* - * Free a list of 0-order pages + * Free a batch of folios */ -void free_unref_page_list(struct list_head *list) +void free_unref_folios(struct folio_batch *folios) { - struct page *page, *next; - unsigned long flags, pfn; - int batch_count = 0; + unsigned long UP_flags; + struct per_cpu_pages *pcp = NULL; + struct zone *locked_zone = NULL; + int i, j; - /* Prepare pages for freeing */ - list_for_each_entry_safe(page, next, list, lru) { - pfn = page_to_pfn(page); - if (!free_unref_page_prepare(page, pfn)) - list_del(&page->lru); - set_page_private(page, pfn); - } + /* Prepare folios for freeing */ + for (i = 0, j = 0; i < folios->nr; i++) { + struct folio *folio = folios->folios[i]; + unsigned long pfn = folio_pfn(folio); + unsigned int order = folio_order(folio); - local_irq_save(flags); - list_for_each_entry_safe(page, next, list, lru) { - unsigned long pfn = page_private(page); + if (!free_pages_prepare(&folio->page, order)) + continue; + /* + * Free orders not handled on the PCP directly to the + * allocator. + */ + if (!pcp_allowed_order(order)) { + free_one_page(folio_zone(folio), &folio->page, + pfn, order, FPI_NONE); + continue; + } + folio->private = (void *)(unsigned long)order; + if (j != i) + folios->folios[j] = folio; + j++; + } + folios->nr = j; + + for (i = 0; i < folios->nr; i++) { + struct folio *folio = folios->folios[i]; + struct zone *zone = folio_zone(folio); + unsigned long pfn = folio_pfn(folio); + unsigned int order = (unsigned long)folio->private; + int migratetype; + + folio->private = NULL; + migratetype = get_pfnblock_migratetype(&folio->page, pfn); + + /* Different zone requires a different pcp lock */ + if (zone != locked_zone || + is_migrate_isolate(migratetype)) { + if (pcp) { + pcp_spin_unlock(pcp, UP_flags); + locked_zone = NULL; + pcp = NULL; + } + + /* + * Free isolated pages directly to the + * allocator, see comment in free_frozen_pages. + */ + if (is_migrate_isolate(migratetype)) { + free_one_page(zone, &folio->page, pfn, + order, FPI_NONE); + continue; + } - set_page_private(page, 0); - trace_mm_page_free_batched(page); - free_unref_page_commit(page, pfn); + /* + * trylock is necessary as folios may be getting freed + * from IRQ or SoftIRQ context after an IO completion. + */ + pcp = pcp_spin_trylock(zone->per_cpu_pageset, UP_flags); + if (unlikely(!pcp)) { + free_one_page(zone, &folio->page, pfn, + order, FPI_NONE); + continue; + } + locked_zone = zone; + } /* - * Guard against excessive IRQ disabled times when we get - * a large list of pages to free. + * Non-isolated types over MIGRATE_PCPTYPES get added + * to the MIGRATE_MOVABLE pcp list. */ - if (++batch_count == SWAP_CLUSTER_MAX) { - local_irq_restore(flags); - batch_count = 0; - local_irq_save(flags); + if (unlikely(migratetype >= MIGRATE_PCPTYPES)) + migratetype = MIGRATE_MOVABLE; + + trace_mm_page_free_batched(&folio->page); + if (!free_frozen_page_commit(zone, pcp, &folio->page, + migratetype, order, FPI_NONE, &UP_flags)) { + pcp = NULL; + locked_zone = NULL; } } - local_irq_restore(flags); + + if (pcp) + pcp_spin_unlock(pcp, UP_flags); + folio_batch_reinit(folios); } /* @@ -2928,39 +3094,31 @@ void split_page(struct page *page, unsigned int order) for (i = 1; i < (1 << order); i++) set_page_refcounted(page + i); - split_page_owner(page, order); + split_page_owner(page, order, 0); + pgalloc_tag_split(page_folio(page), order, 0); + split_page_memcg(page, order); } EXPORT_SYMBOL_GPL(split_page); int __isolate_free_page(struct page *page, unsigned int order) { - unsigned long watermark; - struct zone *zone; - int mt; - - BUG_ON(!PageBuddy(page)); - - zone = page_zone(page); - mt = get_pageblock_migratetype(page); + struct zone *zone = page_zone(page); + int mt = get_pageblock_migratetype(page); if (!is_migrate_isolate(mt)) { + unsigned long watermark; /* * Obey watermarks as if the page was being allocated. We can * emulate a high-order watermark check with a raised order-0 * watermark, because we already know our high-order page * exists. */ - watermark = min_wmark_pages(zone) + (1UL << order); + watermark = zone->_watermark[WMARK_MIN] + (1UL << order); if (!zone_watermark_ok(zone, 0, watermark, 0, ALLOC_CMA)) return 0; - - __mod_zone_freepage_state(zone, -(1UL << order), mt); } - /* Remove page from free list */ - list_del(&page->lru); - zone->free_area[order].nr_free--; - rmv_page_order(page); + del_page_from_free_list(page, zone, order, mt); /* * Set the pageblock if the isolated page is at least half of a @@ -2970,23 +3128,45 @@ int __isolate_free_page(struct page *page, unsigned int order) struct page *endpage = page + (1 << order) - 1; for (; page < endpage; page += pageblock_nr_pages) { int mt = get_pageblock_migratetype(page); - if (!is_migrate_isolate(mt) && !is_migrate_cma(mt) - && !is_migrate_highatomic(mt)) - set_pageblock_migratetype(page, - MIGRATE_MOVABLE); + /* + * Only change normal pageblocks (i.e., they can merge + * with others) + */ + if (migratetype_is_mergeable(mt)) + move_freepages_block(zone, page, mt, + MIGRATE_MOVABLE); } } - return 1UL << order; } +/** + * __putback_isolated_page - Return a now-isolated page back where we got it + * @page: Page that was isolated + * @order: Order of the isolated page + * @mt: The page's pageblock's migratetype + * + * This function is meant to return a page pulled from the free lists via + * __isolate_free_page back to the free lists they were pulled from. + */ +void __putback_isolated_page(struct page *page, unsigned int order, int mt) +{ + struct zone *zone = page_zone(page); + + /* zone lock should be held when this function is called */ + lockdep_assert_held(&zone->lock); + + /* Return isolated page to tail of freelist. */ + __free_one_page(page, page_to_pfn(page), zone, order, mt, + FPI_SKIP_REPORT_NOTIFY | FPI_TO_TAIL); +} + /* * Update NUMA hit/miss statistics - * - * Must be called with interrupts disabled. */ -static inline void zone_statistics(struct zone *preferred_zone, struct zone *z) +static inline void zone_statistics(struct zone *preferred_zone, struct zone *z, + long nr_account) { #ifdef CONFIG_NUMA enum numa_stat_item local_stat = NUMA_LOCAL; @@ -2999,17 +3179,115 @@ static inline void zone_statistics(struct zone *preferred_zone, struct zone *z) local_stat = NUMA_OTHER; if (zone_to_nid(z) == zone_to_nid(preferred_zone)) - __inc_numa_state(z, NUMA_HIT); + __count_numa_events(z, NUMA_HIT, nr_account); else { - __inc_numa_state(z, NUMA_MISS); - __inc_numa_state(preferred_zone, NUMA_FOREIGN); + __count_numa_events(z, NUMA_MISS, nr_account); + __count_numa_events(preferred_zone, NUMA_FOREIGN, nr_account); } - __inc_numa_state(z, local_stat); + __count_numa_events(z, local_stat, nr_account); #endif } +static __always_inline +struct page *rmqueue_buddy(struct zone *preferred_zone, struct zone *zone, + unsigned int order, unsigned int alloc_flags, + int migratetype) +{ + struct page *page; + unsigned long flags; + + do { + page = NULL; + if (unlikely(alloc_flags & ALLOC_TRYLOCK)) { + if (!spin_trylock_irqsave(&zone->lock, flags)) + return NULL; + } else { + spin_lock_irqsave(&zone->lock, flags); + } + if (alloc_flags & ALLOC_HIGHATOMIC) + page = __rmqueue_smallest(zone, order, MIGRATE_HIGHATOMIC); + if (!page) { + enum rmqueue_mode rmqm = RMQUEUE_NORMAL; + + page = __rmqueue(zone, order, migratetype, alloc_flags, &rmqm); + + /* + * If the allocation fails, allow OOM handling and + * order-0 (atomic) allocs access to HIGHATOMIC + * reserves as failing now is worse than failing a + * high-order atomic allocation in the future. + */ + if (!page && (alloc_flags & (ALLOC_OOM|ALLOC_NON_BLOCK))) + page = __rmqueue_smallest(zone, order, MIGRATE_HIGHATOMIC); + + if (!page) { + spin_unlock_irqrestore(&zone->lock, flags); + return NULL; + } + } + spin_unlock_irqrestore(&zone->lock, flags); + } while (check_new_pages(page, order)); + + __count_zid_vm_events(PGALLOC, page_zonenum(page), 1 << order); + zone_statistics(preferred_zone, zone, 1); + + return page; +} + +static int nr_pcp_alloc(struct per_cpu_pages *pcp, struct zone *zone, int order) +{ + int high, base_batch, batch, max_nr_alloc; + int high_max, high_min; + + base_batch = READ_ONCE(pcp->batch); + high_min = READ_ONCE(pcp->high_min); + high_max = READ_ONCE(pcp->high_max); + high = pcp->high = clamp(pcp->high, high_min, high_max); + + /* Check for PCP disabled or boot pageset */ + if (unlikely(high < base_batch)) + return 1; + + if (order) + batch = base_batch; + else + batch = (base_batch << pcp->alloc_factor); + + /* + * If we had larger pcp->high, we could avoid to allocate from + * zone. + */ + if (high_min != high_max && !test_bit(ZONE_BELOW_HIGH, &zone->flags)) + high = pcp->high = min(high + batch, high_max); + + if (!order) { + max_nr_alloc = max(high - pcp->count - base_batch, base_batch); + /* + * Double the number of pages allocated each time there is + * subsequent allocation of order-0 pages without any freeing. + */ + if (batch <= max_nr_alloc && + pcp->alloc_factor < CONFIG_PCP_BATCH_SCALE_MAX) + pcp->alloc_factor++; + batch = min(batch, max_nr_alloc); + } + + /* + * Scale batch relative to order if batch implies free pages + * can be stored on the PCP. Batch can be 1 for small zones or + * for boot pagesets which should never store free pages as + * the pages may belong to arbitrary zones. + */ + if (batch > 1) + batch = max(batch >> order, 2); + + return batch; +} + /* Remove page from the per-cpu list, caller must protect the list */ -static struct page *__rmqueue_pcplist(struct zone *zone, int migratetype, +static inline +struct page *__rmqueue_pcplist(struct zone *zone, unsigned int order, + int migratetype, unsigned int alloc_flags, struct per_cpu_pages *pcp, struct list_head *list) @@ -3018,17 +3296,22 @@ static struct page *__rmqueue_pcplist(struct zone *zone, int migratetype, do { if (list_empty(list)) { - pcp->count += rmqueue_bulk(zone, 0, - pcp->batch, list, + int batch = nr_pcp_alloc(pcp, zone, order); + int alloced; + + alloced = rmqueue_bulk(zone, order, + batch, list, migratetype, alloc_flags); + + pcp->count += alloced << order; if (unlikely(list_empty(list))) return NULL; } - page = list_first_entry(list, struct page, lru); - list_del(&page->lru); - pcp->count--; - } while (check_new_pcp(page)); + page = list_first_entry(list, struct page, pcp_list); + list_del(&page->pcp_list); + pcp->count -= 1 << order; + } while (check_new_pages(page, order)); return page; } @@ -3036,169 +3319,232 @@ static struct page *__rmqueue_pcplist(struct zone *zone, int migratetype, /* Lock and remove page from the per-cpu list */ static struct page *rmqueue_pcplist(struct zone *preferred_zone, struct zone *zone, unsigned int order, - gfp_t gfp_flags, int migratetype, - unsigned int alloc_flags) + int migratetype, unsigned int alloc_flags) { struct per_cpu_pages *pcp; struct list_head *list; struct page *page; - unsigned long flags; + unsigned long UP_flags; - local_irq_save(flags); - pcp = &this_cpu_ptr(zone->pageset)->pcp; - list = &pcp->lists[migratetype]; - page = __rmqueue_pcplist(zone, migratetype, alloc_flags, pcp, list); + /* spin_trylock may fail due to a parallel drain or IRQ reentrancy. */ + pcp = pcp_spin_trylock(zone->per_cpu_pageset, UP_flags); + if (!pcp) + return NULL; + + /* + * On allocation, reduce the number of pages that are batch freed. + * See nr_pcp_free() where free_factor is increased for subsequent + * frees. + */ + pcp->free_count >>= 1; + list = &pcp->lists[order_to_pindex(migratetype, order)]; + page = __rmqueue_pcplist(zone, order, migratetype, alloc_flags, pcp, list); + pcp_spin_unlock(pcp, UP_flags); if (page) { __count_zid_vm_events(PGALLOC, page_zonenum(page), 1 << order); - zone_statistics(preferred_zone, zone); + zone_statistics(preferred_zone, zone, 1); } - local_irq_restore(flags); return page; } /* - * Allocate a page from the given zone. Use pcplists for order-0 allocations. + * Allocate a page from the given zone. + * Use pcplists for THP or "cheap" high-order allocations. + */ + +/* + * Do not instrument rmqueue() with KMSAN. This function may call + * __msan_poison_alloca() through a call to set_pfnblock_migratetype(). + * If __msan_poison_alloca() attempts to allocate pages for the stack depot, it + * may call rmqueue() again, which will result in a deadlock. */ +__no_sanitize_memory static inline struct page *rmqueue(struct zone *preferred_zone, struct zone *zone, unsigned int order, gfp_t gfp_flags, unsigned int alloc_flags, int migratetype) { - unsigned long flags; struct page *page; - if (likely(order == 0)) { + if (likely(pcp_allowed_order(order))) { page = rmqueue_pcplist(preferred_zone, zone, order, - gfp_flags, migratetype, alloc_flags); - goto out; + migratetype, alloc_flags); + if (likely(page)) + goto out; } - /* - * We most definitely don't want callers attempting to - * allocate greater than order-1 page units with __GFP_NOFAIL. - */ - WARN_ON_ONCE((gfp_flags & __GFP_NOFAIL) && (order > 1)); - spin_lock_irqsave(&zone->lock, flags); - - do { - page = NULL; - if (alloc_flags & ALLOC_HARDER) { - page = __rmqueue_smallest(zone, order, MIGRATE_HIGHATOMIC); - if (page) - trace_mm_page_alloc_zone_locked(page, order, migratetype); - } - if (!page) - page = __rmqueue(zone, order, migratetype, alloc_flags); - } while (page && check_new_pages(page, order)); - spin_unlock(&zone->lock); - if (!page) - goto failed; - __mod_zone_freepage_state(zone, -(1 << order), - get_pcppage_migratetype(page)); - - __count_zid_vm_events(PGALLOC, page_zonenum(page), 1 << order); - zone_statistics(preferred_zone, zone); - local_irq_restore(flags); + page = rmqueue_buddy(preferred_zone, zone, order, alloc_flags, + migratetype); out: /* Separate test+clear to avoid unnecessary atomics */ - if (test_bit(ZONE_BOOSTED_WATERMARK, &zone->flags)) { + if ((alloc_flags & ALLOC_KSWAPD) && + unlikely(test_bit(ZONE_BOOSTED_WATERMARK, &zone->flags))) { clear_bit(ZONE_BOOSTED_WATERMARK, &zone->flags); wakeup_kswapd(zone, 0, 0, zone_idx(zone)); } VM_BUG_ON_PAGE(page && bad_range(zone, page), page); return page; - -failed: - local_irq_restore(flags); - return NULL; } -#ifdef CONFIG_FAIL_PAGE_ALLOC +/* + * Reserve the pageblock(s) surrounding an allocation request for + * exclusive use of high-order atomic allocations if there are no + * empty page blocks that contain a page with a suitable order + */ +static void reserve_highatomic_pageblock(struct page *page, int order, + struct zone *zone) +{ + int mt; + unsigned long max_managed, flags; + + /* + * The number reserved as: minimum is 1 pageblock, maximum is + * roughly 1% of a zone. But if 1% of a zone falls below a + * pageblock size, then don't reserve any pageblocks. + * Check is race-prone but harmless. + */ + if ((zone_managed_pages(zone) / 100) < pageblock_nr_pages) + return; + max_managed = ALIGN((zone_managed_pages(zone) / 100), pageblock_nr_pages); + if (zone->nr_reserved_highatomic >= max_managed) + return; -static struct { - struct fault_attr attr; + spin_lock_irqsave(&zone->lock, flags); - bool ignore_gfp_highmem; - bool ignore_gfp_reclaim; - u32 min_order; -} fail_page_alloc = { - .attr = FAULT_ATTR_INITIALIZER, - .ignore_gfp_reclaim = true, - .ignore_gfp_highmem = true, - .min_order = 1, -}; + /* Recheck the nr_reserved_highatomic limit under the lock */ + if (zone->nr_reserved_highatomic >= max_managed) + goto out_unlock; -static int __init setup_fail_page_alloc(char *str) -{ - return setup_fault_attr(&fail_page_alloc.attr, str); -} -__setup("fail_page_alloc=", setup_fail_page_alloc); + /* Yoink! */ + mt = get_pageblock_migratetype(page); + /* Only reserve normal pageblocks (i.e., they can merge with others) */ + if (!migratetype_is_mergeable(mt)) + goto out_unlock; -static bool __should_fail_alloc_page(gfp_t gfp_mask, unsigned int order) -{ - if (order < fail_page_alloc.min_order) - return false; - if (gfp_mask & __GFP_NOFAIL) - return false; - if (fail_page_alloc.ignore_gfp_highmem && (gfp_mask & __GFP_HIGHMEM)) - return false; - if (fail_page_alloc.ignore_gfp_reclaim && - (gfp_mask & __GFP_DIRECT_RECLAIM)) - return false; + if (order < pageblock_order) { + if (move_freepages_block(zone, page, mt, MIGRATE_HIGHATOMIC) == -1) + goto out_unlock; + zone->nr_reserved_highatomic += pageblock_nr_pages; + } else { + change_pageblock_range(page, order, MIGRATE_HIGHATOMIC); + zone->nr_reserved_highatomic += 1 << order; + } - return should_fail(&fail_page_alloc.attr, 1 << order); +out_unlock: + spin_unlock_irqrestore(&zone->lock, flags); } -#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS - -static int __init fail_page_alloc_debugfs(void) +/* + * Used when an allocation is about to fail under memory pressure. This + * potentially hurts the reliability of high-order allocations when under + * intense memory pressure but failed atomic allocations should be easier + * to recover from than an OOM. + * + * If @force is true, try to unreserve pageblocks even though highatomic + * pageblock is exhausted. + */ +static bool unreserve_highatomic_pageblock(const struct alloc_context *ac, + bool force) { - umode_t mode = S_IFREG | 0600; - struct dentry *dir; - - dir = fault_create_debugfs_attr("fail_page_alloc", NULL, - &fail_page_alloc.attr); - if (IS_ERR(dir)) - return PTR_ERR(dir); - - if (!debugfs_create_bool("ignore-gfp-wait", mode, dir, - &fail_page_alloc.ignore_gfp_reclaim)) - goto fail; - if (!debugfs_create_bool("ignore-gfp-highmem", mode, dir, - &fail_page_alloc.ignore_gfp_highmem)) - goto fail; - if (!debugfs_create_u32("min-order", mode, dir, - &fail_page_alloc.min_order)) - goto fail; + struct zonelist *zonelist = ac->zonelist; + unsigned long flags; + struct zoneref *z; + struct zone *zone; + struct page *page; + int order; + int ret; - return 0; -fail: - debugfs_remove_recursive(dir); + for_each_zone_zonelist_nodemask(zone, z, zonelist, ac->highest_zoneidx, + ac->nodemask) { + /* + * Preserve at least one pageblock unless memory pressure + * is really high. + */ + if (!force && zone->nr_reserved_highatomic <= + pageblock_nr_pages) + continue; - return -ENOMEM; -} + spin_lock_irqsave(&zone->lock, flags); + for (order = 0; order < NR_PAGE_ORDERS; order++) { + struct free_area *area = &(zone->free_area[order]); + unsigned long size; -late_initcall(fail_page_alloc_debugfs); + page = get_page_from_free_area(area, MIGRATE_HIGHATOMIC); + if (!page) + continue; -#endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */ + size = max(pageblock_nr_pages, 1UL << order); + /* + * It should never happen but changes to + * locking could inadvertently allow a per-cpu + * drain to add pages to MIGRATE_HIGHATOMIC + * while unreserving so be safe and watch for + * underflows. + */ + if (WARN_ON_ONCE(size > zone->nr_reserved_highatomic)) + size = zone->nr_reserved_highatomic; + zone->nr_reserved_highatomic -= size; -#else /* CONFIG_FAIL_PAGE_ALLOC */ + /* + * Convert to ac->migratetype and avoid the normal + * pageblock stealing heuristics. Minimally, the caller + * is doing the work and needs the pages. More + * importantly, if the block was always converted to + * MIGRATE_UNMOVABLE or another type then the number + * of pageblocks that cannot be completely freed + * may increase. + */ + if (order < pageblock_order) + ret = move_freepages_block(zone, page, + MIGRATE_HIGHATOMIC, + ac->migratetype); + else { + move_to_free_list(page, zone, order, + MIGRATE_HIGHATOMIC, + ac->migratetype); + change_pageblock_range(page, order, + ac->migratetype); + ret = 1; + } + /* + * Reserving the block(s) already succeeded, + * so this should not fail on zone boundaries. + */ + WARN_ON_ONCE(ret == -1); + if (ret > 0) { + spin_unlock_irqrestore(&zone->lock, flags); + return ret; + } + } + spin_unlock_irqrestore(&zone->lock, flags); + } -static inline bool __should_fail_alloc_page(gfp_t gfp_mask, unsigned int order) -{ return false; } -#endif /* CONFIG_FAIL_PAGE_ALLOC */ - -static noinline bool should_fail_alloc_page(gfp_t gfp_mask, unsigned int order) +static inline long __zone_watermark_unusable_free(struct zone *z, + unsigned int order, unsigned int alloc_flags) { - return __should_fail_alloc_page(gfp_mask, order); + long unusable_free = (1 << order) - 1; + + /* + * If the caller does not have rights to reserves below the min + * watermark then subtract the free pages reserved for highatomic. + */ + if (likely(!(alloc_flags & ALLOC_RESERVES))) + unusable_free += READ_ONCE(z->nr_free_highatomic); + +#ifdef CONFIG_CMA + /* If allocation can't use CMA areas don't use free CMA pages */ + if (!(alloc_flags & ALLOC_CMA)) + unusable_free += zone_page_state(z, NR_FREE_CMA_PAGES); +#endif + + return unusable_free; } -ALLOW_ERROR_INJECTION(should_fail_alloc_page, TRUE); /* * Return true if free base pages are above 'mark'. For high-order checks it @@ -3207,52 +3553,50 @@ ALLOW_ERROR_INJECTION(should_fail_alloc_page, TRUE); * to check in the allocation paths if no pages are free. */ bool __zone_watermark_ok(struct zone *z, unsigned int order, unsigned long mark, - int classzone_idx, unsigned int alloc_flags, + int highest_zoneidx, unsigned int alloc_flags, long free_pages) { long min = mark; int o; - const bool alloc_harder = (alloc_flags & (ALLOC_HARDER|ALLOC_OOM)); /* free_pages may go negative - that's OK */ - free_pages -= (1 << order) - 1; + free_pages -= __zone_watermark_unusable_free(z, order, alloc_flags); - if (alloc_flags & ALLOC_HIGH) - min -= min / 2; + if (unlikely(alloc_flags & ALLOC_RESERVES)) { + /* + * __GFP_HIGH allows access to 50% of the min reserve as well + * as OOM. + */ + if (alloc_flags & ALLOC_MIN_RESERVE) { + min -= min / 2; + + /* + * Non-blocking allocations (e.g. GFP_ATOMIC) can + * access more reserves than just __GFP_HIGH. Other + * non-blocking allocations requests such as GFP_NOWAIT + * or (GFP_KERNEL & ~__GFP_DIRECT_RECLAIM) do not get + * access to the min reserve. + */ + if (alloc_flags & ALLOC_NON_BLOCK) + min -= min / 4; + } - /* - * If the caller does not have rights to ALLOC_HARDER then subtract - * the high-atomic reserves. This will over-estimate the size of the - * atomic reserve but it avoids a search. - */ - if (likely(!alloc_harder)) { - free_pages -= z->nr_reserved_highatomic; - } else { /* - * OOM victims can try even harder than normal ALLOC_HARDER + * OOM victims can try even harder than the normal reserve * users on the grounds that it's definitely going to be in * the exit path shortly and free memory. Any allocation it * makes during the free path will be small and short-lived. */ if (alloc_flags & ALLOC_OOM) min -= min / 2; - else - min -= min / 4; } - -#ifdef CONFIG_CMA - /* If allocation can't use CMA areas don't use free CMA pages */ - if (!(alloc_flags & ALLOC_CMA)) - free_pages -= zone_page_state(z, NR_FREE_CMA_PAGES); -#endif - /* * Check watermarks for an order-0 allocation request. If these * are not met, then a high-order request also cannot go ahead * even if a suitable page happened to be free. */ - if (free_pages <= min + z->lowmem_reserve[classzone_idx]) + if (free_pages <= min + z->lowmem_reserve[highest_zoneidx]) return false; /* If this is an order-0 request then the watermark is fine */ @@ -3260,7 +3604,7 @@ bool __zone_watermark_ok(struct zone *z, unsigned int order, unsigned long mark, return true; /* For a high-order request, check at least one suitable page is free */ - for (o = order; o < MAX_ORDER; o++) { + for (o = order; o < NR_PAGE_ORDERS; o++) { struct free_area *area = &z->free_area[o]; int mt; @@ -3268,73 +3612,83 @@ bool __zone_watermark_ok(struct zone *z, unsigned int order, unsigned long mark, continue; for (mt = 0; mt < MIGRATE_PCPTYPES; mt++) { - if (!list_empty(&area->free_list[mt])) + if (!free_area_empty(area, mt)) return true; } #ifdef CONFIG_CMA if ((alloc_flags & ALLOC_CMA) && - !list_empty(&area->free_list[MIGRATE_CMA])) { + !free_area_empty(area, MIGRATE_CMA)) { return true; } #endif - if (alloc_harder && - !list_empty(&area->free_list[MIGRATE_HIGHATOMIC])) + if ((alloc_flags & (ALLOC_HIGHATOMIC|ALLOC_OOM)) && + !free_area_empty(area, MIGRATE_HIGHATOMIC)) { return true; + } } return false; } bool zone_watermark_ok(struct zone *z, unsigned int order, unsigned long mark, - int classzone_idx, unsigned int alloc_flags) + int highest_zoneidx, unsigned int alloc_flags) { - return __zone_watermark_ok(z, order, mark, classzone_idx, alloc_flags, + return __zone_watermark_ok(z, order, mark, highest_zoneidx, alloc_flags, zone_page_state(z, NR_FREE_PAGES)); } static inline bool zone_watermark_fast(struct zone *z, unsigned int order, - unsigned long mark, int classzone_idx, unsigned int alloc_flags) + unsigned long mark, int highest_zoneidx, + unsigned int alloc_flags, gfp_t gfp_mask) { - long free_pages = zone_page_state(z, NR_FREE_PAGES); - long cma_pages = 0; + long free_pages; -#ifdef CONFIG_CMA - /* If allocation can't use CMA areas don't use free CMA pages */ - if (!(alloc_flags & ALLOC_CMA)) - cma_pages = zone_page_state(z, NR_FREE_CMA_PAGES); -#endif + free_pages = zone_page_state(z, NR_FREE_PAGES); /* * Fast check for order-0 only. If this fails then the reserves - * need to be calculated. There is a corner case where the check - * passes but only the high-order atomic reserve are free. If - * the caller is !atomic then it'll uselessly search the free - * list. That corner case is then slower but it is harmless. + * need to be calculated. */ - if (!order && (free_pages - cma_pages) > mark + z->lowmem_reserve[classzone_idx]) - return true; + if (!order) { + long usable_free; + long reserved; - return __zone_watermark_ok(z, order, mark, classzone_idx, alloc_flags, - free_pages); -} + usable_free = free_pages; + reserved = __zone_watermark_unusable_free(z, 0, alloc_flags); -bool zone_watermark_ok_safe(struct zone *z, unsigned int order, - unsigned long mark, int classzone_idx) -{ - long free_pages = zone_page_state(z, NR_FREE_PAGES); + /* reserved may over estimate high-atomic reserves. */ + usable_free -= min(usable_free, reserved); + if (usable_free > mark + z->lowmem_reserve[highest_zoneidx]) + return true; + } - if (z->percpu_drift_mark && free_pages < z->percpu_drift_mark) - free_pages = zone_page_state_snapshot(z, NR_FREE_PAGES); + if (__zone_watermark_ok(z, order, mark, highest_zoneidx, alloc_flags, + free_pages)) + return true; - return __zone_watermark_ok(z, order, mark, classzone_idx, 0, - free_pages); + /* + * Ignore watermark boosting for __GFP_HIGH order-0 allocations + * when checking the min watermark. The min watermark is the + * point where boosting is ignored so that kswapd is woken up + * when below the low watermark. + */ + if (unlikely(!order && (alloc_flags & ALLOC_MIN_RESERVE) && z->watermark_boost + && ((alloc_flags & ALLOC_WMARK_MASK) == WMARK_MIN))) { + mark = z->_watermark[WMARK_MIN]; + return __zone_watermark_ok(z, order, mark, highest_zoneidx, + alloc_flags, free_pages); + } + + return false; } #ifdef CONFIG_NUMA +int __read_mostly node_reclaim_distance = RECLAIM_DISTANCE; + static bool zone_allows_reclaim(struct zone *local_zone, struct zone *zone) { return node_distance(zone_to_nid(local_zone), zone_to_nid(zone)) <= - RECLAIM_DISTANCE; + node_reclaim_distance; } #else /* CONFIG_NUMA */ static bool zone_allows_reclaim(struct zone *local_zone, struct zone *zone) @@ -3354,14 +3708,25 @@ static bool zone_allows_reclaim(struct zone *local_zone, struct zone *zone) static inline unsigned int alloc_flags_nofragment(struct zone *zone, gfp_t gfp_mask) { - unsigned int alloc_flags = 0; + unsigned int alloc_flags; + + /* + * __GFP_KSWAPD_RECLAIM is assumed to be the same as ALLOC_KSWAPD + * to save a branch. + */ + alloc_flags = (__force int) (gfp_mask & __GFP_KSWAPD_RECLAIM); - if (gfp_mask & __GFP_KSWAPD_RECLAIM) - alloc_flags |= ALLOC_KSWAPD; + if (defrag_mode) { + alloc_flags |= ALLOC_NOFRAGMENT; + return alloc_flags; + } #ifdef CONFIG_ZONE_DMA32 + if (!zone) + return alloc_flags; + if (zone_idx(zone) != ZONE_NORMAL) - goto out; + return alloc_flags; /* * If ZONE_DMA32 exists, assume it is the one after ZONE_NORMAL and @@ -3370,13 +3735,24 @@ alloc_flags_nofragment(struct zone *zone, gfp_t gfp_mask) */ BUILD_BUG_ON(ZONE_NORMAL - ZONE_DMA32 != 1); if (nr_online_nodes > 1 && !populated_zone(--zone)) - goto out; + return alloc_flags; -out: + alloc_flags |= ALLOC_NOFRAGMENT; #endif /* CONFIG_ZONE_DMA32 */ return alloc_flags; } +/* Must be called after current_gfp_context() which can change gfp_mask */ +static inline unsigned int gfp_to_alloc_flags_cma(gfp_t gfp_mask, + unsigned int alloc_flags) +{ +#ifdef CONFIG_CMA + if (gfp_migratetype(gfp_mask) == MIGRATE_MOVABLE) + alloc_flags |= ALLOC_CMA; +#endif + return alloc_flags; +} + /* * get_page_from_freelist goes through the zonelist trying to allocate * a page. @@ -3387,18 +3763,21 @@ get_page_from_freelist(gfp_t gfp_mask, unsigned int order, int alloc_flags, { struct zoneref *z; struct zone *zone; - struct pglist_data *last_pgdat_dirty_limit = NULL; + struct pglist_data *last_pgdat = NULL; + bool last_pgdat_dirty_ok = false; bool no_fallback; + bool skip_kswapd_nodes = nr_online_nodes > 1; + bool skipped_kswapd_nodes = false; retry: /* * Scan zonelist, looking for a zone with enough free. - * See also __cpuset_node_allowed() comment in kernel/cpuset.c. + * See also cpuset_current_node_allowed() comment in kernel/cgroup/cpuset.c. */ no_fallback = alloc_flags & ALLOC_NOFRAGMENT; z = ac->preferred_zoneref; - for_next_zone_zonelist_nodemask(zone, z, ac->zonelist, ac->high_zoneidx, - ac->nodemask) { + for_next_zone_zonelist_nodemask(zone, z, ac->highest_zoneidx, + ac->nodemask) { struct page *page; unsigned long mark; @@ -3426,17 +3805,17 @@ retry: * dirty-throttling and the flusher threads. */ if (ac->spread_dirty_pages) { - if (last_pgdat_dirty_limit == zone->zone_pgdat) - continue; + if (last_pgdat != zone->zone_pgdat) { + last_pgdat = zone->zone_pgdat; + last_pgdat_dirty_ok = node_dirty_ok(zone->zone_pgdat); + } - if (!node_dirty_ok(zone->zone_pgdat)) { - last_pgdat_dirty_limit = zone->zone_pgdat; + if (!last_pgdat_dirty_ok) continue; - } } - if (no_fallback && nr_online_nodes > 1 && - zone != ac->preferred_zoneref->zone) { + if (no_fallback && !defrag_mode && nr_online_nodes > 1 && + zone != zonelist_zone(ac->preferred_zoneref)) { int local_nid; /* @@ -3444,35 +3823,71 @@ retry: * fragmenting fallbacks. Locality is more important * than fragmentation avoidance. */ - local_nid = zone_to_nid(ac->preferred_zoneref->zone); + local_nid = zonelist_node_idx(ac->preferred_zoneref); if (zone_to_nid(zone) != local_nid) { alloc_flags &= ~ALLOC_NOFRAGMENT; goto retry; } } + /* + * If kswapd is already active on a node, keep looking + * for other nodes that might be idle. This can happen + * if another process has NUMA bindings and is causing + * kswapd wakeups on only some nodes. Avoid accidental + * "node_reclaim_mode"-like behavior in this case. + */ + if (skip_kswapd_nodes && + !waitqueue_active(&zone->zone_pgdat->kswapd_wait)) { + skipped_kswapd_nodes = true; + continue; + } + + cond_accept_memory(zone, order, alloc_flags); + + /* + * Detect whether the number of free pages is below high + * watermark. If so, we will decrease pcp->high and free + * PCP pages in free path to reduce the possibility of + * premature page reclaiming. Detection is done here to + * avoid to do that in hotter free path. + */ + if (test_bit(ZONE_BELOW_HIGH, &zone->flags)) + goto check_alloc_wmark; + + mark = high_wmark_pages(zone); + if (zone_watermark_fast(zone, order, mark, + ac->highest_zoneidx, alloc_flags, + gfp_mask)) + goto try_this_zone; + else + set_bit(ZONE_BELOW_HIGH, &zone->flags); + +check_alloc_wmark: mark = wmark_pages(zone, alloc_flags & ALLOC_WMARK_MASK); if (!zone_watermark_fast(zone, order, mark, - ac_classzone_idx(ac), alloc_flags)) { + ac->highest_zoneidx, alloc_flags, + gfp_mask)) { int ret; -#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT + if (cond_accept_memory(zone, order, alloc_flags)) + goto try_this_zone; + /* * Watermark failed for this zone, but see if we can * grow this zone if it contains deferred pages. */ - if (static_branch_unlikely(&deferred_pages)) { + if (deferred_pages_enabled()) { if (_deferred_grow_zone(zone, order)) goto try_this_zone; } -#endif /* Checked here to keep the fast path fast */ BUILD_BUG_ON(ALLOC_NO_WATERMARKS < NR_WMARK); if (alloc_flags & ALLOC_NO_WATERMARKS) goto try_this_zone; - if (node_reclaim_mode == 0 || - !zone_allows_reclaim(ac->preferred_zoneref->zone, zone)) + if (!node_reclaim_enabled() || + !zone_allows_reclaim(zonelist_zone(ac->preferred_zoneref), zone)) continue; ret = node_reclaim(zone->zone_pgdat, gfp_mask, order); @@ -3486,7 +3901,7 @@ retry: default: /* did we reclaim enough */ if (zone_watermark_ok(zone, order, mark, - ac_classzone_idx(ac), alloc_flags)) + ac->highest_zoneidx, alloc_flags)) goto try_this_zone; continue; @@ -3494,7 +3909,7 @@ retry: } try_this_zone: - page = rmqueue(ac->preferred_zoneref->zone, zone, order, + page = rmqueue(zonelist_zone(ac->preferred_zoneref), zone, order, gfp_mask, alloc_flags, ac->migratetype); if (page) { prep_new_page(page, order, gfp_mask, alloc_flags); @@ -3503,26 +3918,36 @@ try_this_zone: * If this is a high-order atomic allocation then check * if the pageblock should be reserved for the future */ - if (unlikely(order && (alloc_flags & ALLOC_HARDER))) - reserve_highatomic_pageblock(page, zone, order); + if (unlikely(alloc_flags & ALLOC_HIGHATOMIC)) + reserve_highatomic_pageblock(page, order, zone); return page; } else { -#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT + if (cond_accept_memory(zone, order, alloc_flags)) + goto try_this_zone; + /* Try again if zone has deferred pages */ - if (static_branch_unlikely(&deferred_pages)) { + if (deferred_pages_enabled()) { if (_deferred_grow_zone(zone, order)) goto try_this_zone; } -#endif } } /* + * If we skipped over nodes with active kswapds and found no + * idle nodes, retry and place anywhere the watermarks permit. + */ + if (skip_kswapd_nodes && skipped_kswapd_nodes) { + skip_kswapd_nodes = false; + goto retry; + } + + /* * It's possible on a UMA machine to get through all zones that are * fragmented. If avoiding fragmentation, reset and try again. */ - if (no_fallback) { + if (no_fallback && !defrag_mode) { alloc_flags &= ~ALLOC_NOFRAGMENT; goto retry; } @@ -3533,10 +3958,6 @@ try_this_zone: static void warn_alloc_show_mem(gfp_t gfp_mask, nodemask_t *nodemask) { unsigned int filter = SHOW_MEM_FILTER_NODES; - static DEFINE_RATELIMIT_STATE(show_mem_rs, HZ, 1); - - if (!__ratelimit(&show_mem_rs)) - return; /* * This documents exceptions given to allocations in certain @@ -3547,20 +3968,22 @@ static void warn_alloc_show_mem(gfp_t gfp_mask, nodemask_t *nodemask) if (tsk_is_oom_victim(current) || (current->flags & (PF_MEMALLOC | PF_EXITING))) filter &= ~SHOW_MEM_FILTER_NODES; - if (in_interrupt() || !(gfp_mask & __GFP_DIRECT_RECLAIM)) + if (!in_task() || !(gfp_mask & __GFP_DIRECT_RECLAIM)) filter &= ~SHOW_MEM_FILTER_NODES; - show_mem(filter, nodemask); + __show_mem(filter, nodemask, gfp_zone(gfp_mask)); + mem_cgroup_show_protected_memory(NULL); } void warn_alloc(gfp_t gfp_mask, nodemask_t *nodemask, const char *fmt, ...) { struct va_format vaf; va_list args; - static DEFINE_RATELIMIT_STATE(nopage_rs, DEFAULT_RATELIMIT_INTERVAL, - DEFAULT_RATELIMIT_BURST); + static DEFINE_RATELIMIT_STATE(nopage_rs, 10*HZ, 1); - if ((gfp_mask & __GFP_NOWARN) || !__ratelimit(&nopage_rs)) + if ((gfp_mask & __GFP_NOWARN) || + !__ratelimit(&nopage_rs) || + ((gfp_mask & __GFP_DMA) && !has_managed_dma())) return; va_start(args, fmt); @@ -3593,7 +4016,6 @@ __alloc_pages_cpuset_fallback(gfp_t gfp_mask, unsigned int order, if (!page) page = get_page_from_freelist(gfp_mask, order, alloc_flags, ac); - return page; } @@ -3646,11 +4068,13 @@ __alloc_pages_may_oom(gfp_t gfp_mask, unsigned int order, * success so it is time to admit defeat. We will skip the OOM killer * because it is very likely that the caller has a more reasonable * fallback than shooting a random task. + * + * The OOM killer may not free memory on a specific node. */ - if (gfp_mask & __GFP_RETRY_MAYFAIL) + if (gfp_mask & (__GFP_RETRY_MAYFAIL | __GFP_THISNODE)) goto out; /* The OOM killer does not needlessly kill tasks for lowmem */ - if (ac->high_zoneidx < ZONE_NORMAL) + if (ac->highest_zoneidx < ZONE_NORMAL) goto out; if (pm_suspended_storage()) goto out; @@ -3664,12 +4088,9 @@ __alloc_pages_may_oom(gfp_t gfp_mask, unsigned int order, * failures more gracefully we should just bail out here. */ - /* The OOM killer may not free memory on a specific node */ - if (gfp_mask & __GFP_THISNODE) - goto out; - /* Exhausted what can be done so it's blame time */ - if (out_of_memory(&oc) || WARN_ON_ONCE(gfp_mask & __GFP_NOFAIL)) { + if (out_of_memory(&oc) || + WARN_ON_ONCE_GFP(gfp_mask & __GFP_NOFAIL, gfp_mask)) { *did_some_progress = 1; /* @@ -3686,7 +4107,7 @@ out: } /* - * Maximum number of compaction retries wit a progress before OOM + * Maximum number of compaction retries with a progress before OOM * killer is consider as the only way to move forward. */ #define MAX_COMPACT_RETRIES 16 @@ -3698,7 +4119,7 @@ __alloc_pages_direct_compact(gfp_t gfp_mask, unsigned int order, unsigned int alloc_flags, const struct alloc_context *ac, enum compact_priority prio, enum compact_result *compact_result) { - struct page *page; + struct page *page = NULL; unsigned long pflags; unsigned int noreclaim_flag; @@ -3706,24 +4127,31 @@ __alloc_pages_direct_compact(gfp_t gfp_mask, unsigned int order, return NULL; psi_memstall_enter(&pflags); + delayacct_compact_start(); noreclaim_flag = memalloc_noreclaim_save(); *compact_result = try_to_compact_pages(gfp_mask, order, alloc_flags, ac, - prio); + prio, &page); memalloc_noreclaim_restore(noreclaim_flag); psi_memstall_leave(&pflags); + delayacct_compact_end(); - if (*compact_result <= COMPACT_INACTIVE) + if (*compact_result == COMPACT_SKIPPED) return NULL; - /* * At least in one zone compaction wasn't deferred or skipped, so let's * count a compaction stall */ count_vm_event(COMPACTSTALL); - page = get_page_from_freelist(gfp_mask, order, alloc_flags, ac); + /* Prep a captured page if available */ + if (page) + prep_new_page(page, order, gfp_mask, alloc_flags); + + /* Try get a page from the freelist if available */ + if (!page) + page = get_page_from_freelist(gfp_mask, order, alloc_flags, ac); if (page) { struct zone *zone = page_zone(page); @@ -3760,48 +4188,44 @@ should_compact_retry(struct alloc_context *ac, int order, int alloc_flags, if (!order) return false; - if (compaction_made_progress(compact_result)) - (*compaction_retries)++; - - /* - * compaction considers all the zone as desperately out of memory - * so it doesn't really make much sense to retry except when the - * failure could be caused by insufficient priority - */ - if (compaction_failed(compact_result)) - goto check_priority; + if (fatal_signal_pending(current)) + return false; /* - * make sure the compaction wasn't deferred or didn't bail out early - * due to locks contention before we declare that we should give up. - * But do not retry if the given zonelist is not suitable for - * compaction. + * Compaction was skipped due to a lack of free order-0 + * migration targets. Continue if reclaim can help. */ - if (compaction_withdrawn(compact_result)) { + if (compact_result == COMPACT_SKIPPED) { ret = compaction_zonelist_suitable(ac, order, alloc_flags); goto out; } /* - * !costly requests are much more important than __GFP_RETRY_MAYFAIL - * costly ones because they are de facto nofail and invoke OOM - * killer to move on while costly can fail and users are ready - * to cope with that. 1/4 retries is rather arbitrary but we - * would need much more detailed feedback from compaction to - * make a better decision. + * Compaction managed to coalesce some page blocks, but the + * allocation failed presumably due to a race. Retry some. */ - if (order > PAGE_ALLOC_COSTLY_ORDER) - max_retries /= 4; - if (*compaction_retries <= max_retries) { - ret = true; - goto out; + if (compact_result == COMPACT_SUCCESS) { + /* + * !costly requests are much more important than + * __GFP_RETRY_MAYFAIL costly ones because they are de + * facto nofail and invoke OOM killer to move on while + * costly can fail and users are ready to cope with + * that. 1/4 retries is rather arbitrary but we would + * need much more detailed feedback from compaction to + * make a better decision. + */ + if (order > PAGE_ALLOC_COSTLY_ORDER) + max_retries /= 4; + + if (++(*compaction_retries) <= max_retries) { + ret = true; + goto out; + } } /* - * Make sure there are attempts at the highest priority if we exhausted - * all retries or failed at the lower priorities. + * Compaction failed. Retry with increasing priority. */ -check_priority: min_priority = (order > PAGE_ALLOC_COSTLY_ORDER) ? MIN_COMPACT_COSTLY_PRIORITY : MIN_COMPACT_PRIORITY; @@ -3825,7 +4249,7 @@ __alloc_pages_direct_compact(gfp_t gfp_mask, unsigned int order, } static inline bool -should_compact_retry(struct alloc_context *ac, unsigned int order, int alloc_flags, +should_compact_retry(struct alloc_context *ac, int order, int alloc_flags, enum compact_result compact_result, enum compact_priority *compact_priority, int *compaction_retries) @@ -3842,10 +4266,10 @@ should_compact_retry(struct alloc_context *ac, unsigned int order, int alloc_fla * Let's give them a good hope and keep retrying while the order-0 * watermarks are OK. */ - for_each_zone_zonelist_nodemask(zone, z, ac->zonelist, ac->high_zoneidx, - ac->nodemask) { + for_each_zone_zonelist_nodemask(zone, z, ac->zonelist, + ac->highest_zoneidx, ac->nodemask) { if (zone_watermark_ok(zone, 0, min_wmark_pages(zone), - ac_classzone_idx(ac), alloc_flags)) + ac->highest_zoneidx, alloc_flags)) return true; } return false; @@ -3856,10 +4280,8 @@ should_compact_retry(struct alloc_context *ac, unsigned int order, int alloc_fla static struct lockdep_map __fs_reclaim_map = STATIC_LOCKDEP_MAP_INIT("fs_reclaim", &__fs_reclaim_map); -static bool __need_fs_reclaim(gfp_t gfp_mask) +static bool __need_reclaim(gfp_t gfp_mask) { - gfp_mask = current_gfp_context(gfp_mask); - /* no reclaim without waiting on it */ if (!(gfp_mask & __GFP_DIRECT_RECLAIM)) return false; @@ -3868,68 +4290,95 @@ static bool __need_fs_reclaim(gfp_t gfp_mask) if (current->flags & PF_MEMALLOC) return false; - /* We're only interested __GFP_FS allocations for now */ - if (!(gfp_mask & __GFP_FS)) - return false; - if (gfp_mask & __GFP_NOLOCKDEP) return false; return true; } -void __fs_reclaim_acquire(void) +void __fs_reclaim_acquire(unsigned long ip) { - lock_map_acquire(&__fs_reclaim_map); + lock_acquire_exclusive(&__fs_reclaim_map, 0, 0, NULL, ip); } -void __fs_reclaim_release(void) +void __fs_reclaim_release(unsigned long ip) { - lock_map_release(&__fs_reclaim_map); + lock_release(&__fs_reclaim_map, ip); } void fs_reclaim_acquire(gfp_t gfp_mask) { - if (__need_fs_reclaim(gfp_mask)) - __fs_reclaim_acquire(); + gfp_mask = current_gfp_context(gfp_mask); + + if (__need_reclaim(gfp_mask)) { + if (gfp_mask & __GFP_FS) + __fs_reclaim_acquire(_RET_IP_); + +#ifdef CONFIG_MMU_NOTIFIER + lock_map_acquire(&__mmu_notifier_invalidate_range_start_map); + lock_map_release(&__mmu_notifier_invalidate_range_start_map); +#endif + + } } EXPORT_SYMBOL_GPL(fs_reclaim_acquire); void fs_reclaim_release(gfp_t gfp_mask) { - if (__need_fs_reclaim(gfp_mask)) - __fs_reclaim_release(); + gfp_mask = current_gfp_context(gfp_mask); + + if (__need_reclaim(gfp_mask)) { + if (gfp_mask & __GFP_FS) + __fs_reclaim_release(_RET_IP_); + } } EXPORT_SYMBOL_GPL(fs_reclaim_release); #endif +/* + * Zonelists may change due to hotplug during allocation. Detect when zonelists + * have been rebuilt so allocation retries. Reader side does not lock and + * retries the allocation if zonelist changes. Writer side is protected by the + * embedded spin_lock. + */ +static DEFINE_SEQLOCK(zonelist_update_seq); + +static unsigned int zonelist_iter_begin(void) +{ + if (IS_ENABLED(CONFIG_MEMORY_HOTREMOVE)) + return read_seqbegin(&zonelist_update_seq); + + return 0; +} + +static unsigned int check_retry_zonelist(unsigned int seq) +{ + if (IS_ENABLED(CONFIG_MEMORY_HOTREMOVE)) + return read_seqretry(&zonelist_update_seq, seq); + + return seq; +} + /* Perform direct synchronous page reclaim */ -static int +static unsigned long __perform_reclaim(gfp_t gfp_mask, unsigned int order, const struct alloc_context *ac) { - struct reclaim_state reclaim_state; - int progress; unsigned int noreclaim_flag; - unsigned long pflags; + unsigned long progress; cond_resched(); /* We now go into synchronous reclaim */ cpuset_memory_pressure_bump(); - psi_memstall_enter(&pflags); fs_reclaim_acquire(gfp_mask); noreclaim_flag = memalloc_noreclaim_save(); - reclaim_state.reclaimed_slab = 0; - current->reclaim_state = &reclaim_state; progress = try_to_free_pages(ac->zonelist, order, gfp_mask, ac->nodemask); - current->reclaim_state = NULL; memalloc_noreclaim_restore(noreclaim_flag); fs_reclaim_release(gfp_mask); - psi_memstall_leave(&pflags); cond_resched(); @@ -3943,11 +4392,13 @@ __alloc_pages_direct_reclaim(gfp_t gfp_mask, unsigned int order, unsigned long *did_some_progress) { struct page *page = NULL; + unsigned long pflags; bool drained = false; + psi_memstall_enter(&pflags); *did_some_progress = __perform_reclaim(gfp_mask, order, ac); if (unlikely(!(*did_some_progress))) - return NULL; + goto out; retry: page = get_page_from_freelist(gfp_mask, order, alloc_flags, ac); @@ -3955,7 +4406,7 @@ retry: /* * If an allocation failed after direct reclaim, it could be because * pages are pinned on the per-cpu lists or in high alloc reserves. - * Shrink them them and try again + * Shrink them and try again */ if (!page && !drained) { unreserve_highatomic_pageblock(ac, false); @@ -3963,6 +4414,8 @@ retry: drained = true; goto retry; } +out: + psi_memstall_leave(&pflags); return page; } @@ -3973,54 +4426,74 @@ static void wake_all_kswapds(unsigned int order, gfp_t gfp_mask, struct zoneref *z; struct zone *zone; pg_data_t *last_pgdat = NULL; - enum zone_type high_zoneidx = ac->high_zoneidx; + enum zone_type highest_zoneidx = ac->highest_zoneidx; + unsigned int reclaim_order; + + if (defrag_mode) + reclaim_order = max(order, pageblock_order); + else + reclaim_order = order; - for_each_zone_zonelist_nodemask(zone, z, ac->zonelist, high_zoneidx, + for_each_zone_zonelist_nodemask(zone, z, ac->zonelist, highest_zoneidx, ac->nodemask) { - if (last_pgdat != zone->zone_pgdat) - wakeup_kswapd(zone, gfp_mask, order, high_zoneidx); + if (!managed_zone(zone)) + continue; + if (last_pgdat == zone->zone_pgdat) + continue; + wakeup_kswapd(zone, gfp_mask, reclaim_order, highest_zoneidx); last_pgdat = zone->zone_pgdat; } } static inline unsigned int -gfp_to_alloc_flags(gfp_t gfp_mask) +gfp_to_alloc_flags(gfp_t gfp_mask, unsigned int order) { unsigned int alloc_flags = ALLOC_WMARK_MIN | ALLOC_CPUSET; - /* __GFP_HIGH is assumed to be the same as ALLOC_HIGH to save a branch. */ - BUILD_BUG_ON(__GFP_HIGH != (__force gfp_t) ALLOC_HIGH); + /* + * __GFP_HIGH is assumed to be the same as ALLOC_MIN_RESERVE + * and __GFP_KSWAPD_RECLAIM is assumed to be the same as ALLOC_KSWAPD + * to save two branches. + */ + BUILD_BUG_ON(__GFP_HIGH != (__force gfp_t) ALLOC_MIN_RESERVE); + BUILD_BUG_ON(__GFP_KSWAPD_RECLAIM != (__force gfp_t) ALLOC_KSWAPD); /* * The caller may dip into page reserves a bit more if the caller * cannot run direct reclaim, or if the caller has realtime scheduling * policy or is asking for __GFP_HIGH memory. GFP_ATOMIC requests will - * set both ALLOC_HARDER (__GFP_ATOMIC) and ALLOC_HIGH (__GFP_HIGH). + * set both ALLOC_NON_BLOCK and ALLOC_MIN_RESERVE(__GFP_HIGH). */ - alloc_flags |= (__force int) (gfp_mask & __GFP_HIGH); + alloc_flags |= (__force int) + (gfp_mask & (__GFP_HIGH | __GFP_KSWAPD_RECLAIM)); - if (gfp_mask & __GFP_ATOMIC) { + if (!(gfp_mask & __GFP_DIRECT_RECLAIM)) { /* * Not worth trying to allocate harder for __GFP_NOMEMALLOC even * if it can't schedule. */ - if (!(gfp_mask & __GFP_NOMEMALLOC)) - alloc_flags |= ALLOC_HARDER; + if (!(gfp_mask & __GFP_NOMEMALLOC)) { + alloc_flags |= ALLOC_NON_BLOCK; + + if (order > 0 && (alloc_flags & ALLOC_MIN_RESERVE)) + alloc_flags |= ALLOC_HIGHATOMIC; + } + /* - * Ignore cpuset mems for GFP_ATOMIC rather than fail, see the - * comment for __cpuset_node_allowed(). + * Ignore cpuset mems for non-blocking __GFP_HIGH (probably + * GFP_ATOMIC) rather than fail, see the comment for + * cpuset_current_node_allowed(). */ - alloc_flags &= ~ALLOC_CPUSET; - } else if (unlikely(rt_task(current)) && !in_interrupt()) - alloc_flags |= ALLOC_HARDER; + if (alloc_flags & ALLOC_MIN_RESERVE) + alloc_flags &= ~ALLOC_CPUSET; + } else if (unlikely(rt_or_dl_task(current)) && in_task()) + alloc_flags |= ALLOC_MIN_RESERVE; - if (gfp_mask & __GFP_KSWAPD_RECLAIM) - alloc_flags |= ALLOC_KSWAPD; + alloc_flags = gfp_to_alloc_flags_cma(gfp_mask, alloc_flags); + + if (defrag_mode) + alloc_flags |= ALLOC_NOFRAGMENT; -#ifdef CONFIG_CMA - if (gfpflags_to_migratetype(gfp_mask) == MIGRATE_MOVABLE) - alloc_flags |= ALLOC_CMA; -#endif return alloc_flags; } @@ -4095,14 +4568,9 @@ should_reclaim_retry(gfp_t gfp_mask, unsigned order, else (*no_progress_loops)++; - /* - * Make sure we converge to OOM if we cannot make any progress - * several times in the row. - */ - if (*no_progress_loops > MAX_RECLAIM_RETRIES) { - /* Before OOM, exhaust highatomic_reserve */ - return unreserve_highatomic_pageblock(ac, true); - } + if (*no_progress_loops > MAX_RECLAIM_RETRIES) + goto out; + /* * Keep reclaiming pages while there is a chance this will lead @@ -4110,13 +4578,18 @@ should_reclaim_retry(gfp_t gfp_mask, unsigned order, * request even if all reclaimable pages are considered then we are * screwed and have to go OOM. */ - for_each_zone_zonelist_nodemask(zone, z, ac->zonelist, ac->high_zoneidx, - ac->nodemask) { + for_each_zone_zonelist_nodemask(zone, z, ac->zonelist, + ac->highest_zoneidx, ac->nodemask) { unsigned long available; unsigned long reclaimable; unsigned long min_wmark = min_wmark_pages(zone); bool wmark; + if (cpusets_enabled() && + (alloc_flags & ALLOC_CPUSET) && + !__cpuset_zone_allowed(zone, gfp_mask)) + continue; + available = reclaimable = zone_reclaimable_pages(zone); available += zone_page_state_snapshot(zone, NR_FREE_PAGES); @@ -4125,34 +4598,15 @@ should_reclaim_retry(gfp_t gfp_mask, unsigned order, * reclaimable pages? */ wmark = __zone_watermark_ok(zone, order, min_wmark, - ac_classzone_idx(ac), alloc_flags, available); + ac->highest_zoneidx, alloc_flags, available); trace_reclaim_retry_zone(z, order, reclaimable, available, min_wmark, *no_progress_loops, wmark); if (wmark) { - /* - * If we didn't make any progress and have a lot of - * dirty + writeback pages then we should wait for - * an IO to complete to slow down the reclaim and - * prevent from pre mature OOM - */ - if (!did_some_progress) { - unsigned long write_pending; - - write_pending = zone_page_state_snapshot(zone, - NR_ZONE_WRITE_PENDING); - - if (2 * write_pending > reclaimable) { - congestion_wait(BLK_RW_ASYNC, HZ/10); - return true; - } - } - ret = true; - goto out; + break; } } -out: /* * Memory allocation/reclaim might be called from a WQ context and the * current implementation of the WQ concurrency control doesn't @@ -4164,6 +4618,11 @@ out: schedule_timeout_uninterruptible(1); else cond_resched(); +out: + /* Before OOM, exhaust highatomic_reserve */ + if (!ret) + return unreserve_highatomic_pageblock(ac, true); + return ret; } @@ -4205,6 +4664,8 @@ __alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order, struct alloc_context *ac) { bool can_direct_reclaim = gfp_mask & __GFP_DIRECT_RECLAIM; + bool can_compact = gfp_compaction_allowed(gfp_mask); + bool nofail = gfp_mask & __GFP_NOFAIL; const bool costly_order = order > PAGE_ALLOC_COSTLY_ORDER; struct page *page = NULL; unsigned int alloc_flags; @@ -4214,28 +4675,37 @@ __alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order, int compaction_retries; int no_progress_loops; unsigned int cpuset_mems_cookie; + unsigned int zonelist_iter_cookie; int reserve_flags; - /* - * We also sanity check to catch abuse of atomic reserves being used by - * callers that are not in atomic context. - */ - if (WARN_ON_ONCE((gfp_mask & (__GFP_ATOMIC|__GFP_DIRECT_RECLAIM)) == - (__GFP_ATOMIC|__GFP_DIRECT_RECLAIM))) - gfp_mask &= ~__GFP_ATOMIC; + if (unlikely(nofail)) { + /* + * Also we don't support __GFP_NOFAIL without __GFP_DIRECT_RECLAIM, + * otherwise, we may result in lockup. + */ + WARN_ON_ONCE(!can_direct_reclaim); + /* + * PF_MEMALLOC request from this context is rather bizarre + * because we cannot reclaim anything and only can loop waiting + * for somebody to do a work for us. + */ + WARN_ON_ONCE(current->flags & PF_MEMALLOC); + } -retry_cpuset: +restart: compaction_retries = 0; no_progress_loops = 0; + compact_result = COMPACT_SKIPPED; compact_priority = DEF_COMPACT_PRIORITY; cpuset_mems_cookie = read_mems_allowed_begin(); + zonelist_iter_cookie = zonelist_iter_begin(); /* * The fast path uses conservative alloc_flags to succeed only until * kswapd needs to be woken up, and to avoid the cost of setting up * alloc_flags precisely. So we do that now. */ - alloc_flags = gfp_to_alloc_flags(gfp_mask); + alloc_flags = gfp_to_alloc_flags(gfp_mask, order); /* * We need to recalculate the starting point for the zonelist iterator @@ -4244,10 +4714,23 @@ retry_cpuset: * could end up iterating over non-eligible zones endlessly. */ ac->preferred_zoneref = first_zones_zonelist(ac->zonelist, - ac->high_zoneidx, ac->nodemask); - if (!ac->preferred_zoneref->zone) + ac->highest_zoneidx, ac->nodemask); + if (!zonelist_zone(ac->preferred_zoneref)) goto nopage; + /* + * Check for insane configurations where the cpuset doesn't contain + * any suitable zone to satisfy the request - e.g. non-movable + * GFP_HIGHUSER allocations from MOVABLE nodes only. + */ + if (cpusets_insane_config() && (gfp_mask & __GFP_HARDWALL)) { + struct zoneref *z = first_zones_zonelist(ac->zonelist, + ac->highest_zoneidx, + &cpuset_current_mems_allowed); + if (!zonelist_zone(z)) + goto nopage; + } + if (alloc_flags & ALLOC_KSWAPD) wake_all_kswapds(order, gfp_mask, ac); @@ -4268,7 +4751,7 @@ retry_cpuset: * Don't try this for allocations that are allowed to ignore * watermarks, as the ALLOC_NO_WATERMARKS attempt didn't yet happen. */ - if (can_direct_reclaim && + if (can_direct_reclaim && can_compact && (costly_order || (order > 0 && ac->migratetype != MIGRATE_MOVABLE)) && !gfp_pfmemalloc_allowed(gfp_mask)) { @@ -4281,18 +4764,28 @@ retry_cpuset: /* * Checks for costly allocations with __GFP_NORETRY, which - * includes THP page fault allocations + * includes some THP page fault allocations */ if (costly_order && (gfp_mask & __GFP_NORETRY)) { /* - * If compaction is deferred for high-order allocations, - * it is because sync compaction recently failed. If - * this is the case and the caller requested a THP - * allocation, we do not want to heavily disrupt the - * system, so we fail the allocation instead of entering - * direct reclaim. + * If allocating entire pageblock(s) and compaction + * failed because all zones are below low watermarks + * or is prohibited because it recently failed at this + * order, fail immediately unless the allocator has + * requested compaction and reclaim retry. + * + * Reclaim is + * - potentially very expensive because zones are far + * below their low watermarks or this is part of very + * bursty high order allocations, + * - not guaranteed to help because isolate_freepages() + * may not iterate over freed pages as part of its + * linear scan, and + * - unlikely to make entire pageblocks free on its + * own. */ - if (compact_result == COMPACT_DEFERRED) + if (compact_result == COMPACT_SKIPPED || + compact_result == COMPACT_DEFERRED) goto nopage; /* @@ -4305,13 +4798,22 @@ retry_cpuset: } retry: + /* + * Deal with possible cpuset update races or zonelist updates to avoid + * infinite retries. + */ + if (check_retry_cpuset(cpuset_mems_cookie, ac) || + check_retry_zonelist(zonelist_iter_cookie)) + goto restart; + /* Ensure kswapd doesn't accidentally go to sleep as long as we loop */ if (alloc_flags & ALLOC_KSWAPD) wake_all_kswapds(order, gfp_mask, ac); reserve_flags = __gfp_pfmemalloc_flags(gfp_mask); if (reserve_flags) - alloc_flags = reserve_flags; + alloc_flags = gfp_to_alloc_flags_cma(gfp_mask, reserve_flags) | + (alloc_flags & ALLOC_KSWAPD); /* * Reset the nodemask and zonelist iterators if memory policies can be @@ -4321,7 +4823,7 @@ retry: if (!(alloc_flags & ALLOC_CPUSET) || reserve_flags) { ac->nodemask = NULL; ac->preferred_zoneref = first_zones_zonelist(ac->zonelist, - ac->high_zoneidx, ac->nodemask); + ac->highest_zoneidx, ac->nodemask); } /* Attempt with potentially adjusted zonelist and alloc_flags */ @@ -4355,9 +4857,10 @@ retry: /* * Do not retry costly high order allocations unless they are - * __GFP_RETRY_MAYFAIL + * __GFP_RETRY_MAYFAIL and we can compact */ - if (costly_order && !(gfp_mask & __GFP_RETRY_MAYFAIL)) + if (costly_order && (!can_compact || + !(gfp_mask & __GFP_RETRY_MAYFAIL))) goto nopage; if (should_reclaim_retry(gfp_mask, order, ac, alloc_flags, @@ -4370,16 +4873,25 @@ retry: * implementation of the compaction depends on the sufficient amount * of free memory (see __compaction_suitable) */ - if (did_some_progress > 0 && + if (did_some_progress > 0 && can_compact && should_compact_retry(ac, order, alloc_flags, compact_result, &compact_priority, &compaction_retries)) goto retry; + /* Reclaim/compaction failed to prevent the fallback */ + if (defrag_mode && (alloc_flags & ALLOC_NOFRAGMENT)) { + alloc_flags &= ~ALLOC_NOFRAGMENT; + goto retry; + } - /* Deal with possible cpuset update races before we start OOM killing */ - if (check_retry_cpuset(cpuset_mems_cookie, ac)) - goto retry_cpuset; + /* + * Deal with possible cpuset update races or zonelist updates to avoid + * a unnecessary OOM kill. + */ + if (check_retry_cpuset(cpuset_mems_cookie, ac) || + check_retry_zonelist(zonelist_iter_cookie)) + goto restart; /* Reclaim has failed us, start killing things */ page = __alloc_pages_may_oom(gfp_mask, order, ac, &did_some_progress); @@ -4388,7 +4900,7 @@ retry: /* Avoid allocations with no watermarks from looping endlessly */ if (tsk_is_oom_victim(current) && - (alloc_flags == ALLOC_OOM || + (alloc_flags & ALLOC_OOM || (gfp_mask & __GFP_NOMEMALLOC))) goto nopage; @@ -4399,44 +4911,35 @@ retry: } nopage: - /* Deal with possible cpuset update races before we fail */ - if (check_retry_cpuset(cpuset_mems_cookie, ac)) - goto retry_cpuset; + /* + * Deal with possible cpuset update races or zonelist updates to avoid + * a unnecessary OOM kill. + */ + if (check_retry_cpuset(cpuset_mems_cookie, ac) || + check_retry_zonelist(zonelist_iter_cookie)) + goto restart; /* * Make sure that __GFP_NOFAIL request doesn't leak out and make sure * we always retry */ - if (gfp_mask & __GFP_NOFAIL) { + if (unlikely(nofail)) { /* - * All existing users of the __GFP_NOFAIL are blockable, so warn - * of any new users that actually require GFP_NOWAIT + * Lacking direct_reclaim we can't do anything to reclaim memory, + * we disregard these unreasonable nofail requests and still + * return NULL */ - if (WARN_ON_ONCE(!can_direct_reclaim)) + if (!can_direct_reclaim) goto fail; /* - * PF_MEMALLOC request from this context is rather bizarre - * because we cannot reclaim anything and only can loop waiting - * for somebody to do a work for us - */ - WARN_ON_ONCE(current->flags & PF_MEMALLOC); - - /* - * non failing costly orders are a hard requirement which we - * are not prepared for much so let's warn about these users - * so that we can identify them and convert them to something - * else. - */ - WARN_ON_ONCE(order > PAGE_ALLOC_COSTLY_ORDER); - - /* - * Help non-failing allocations by giving them access to memory - * reserves but do not use ALLOC_NO_WATERMARKS because this + * Help non-failing allocations by giving some access to memory + * reserves normally used for high priority non-blocking + * allocations but do not use ALLOC_NO_WATERMARKS because this * could deplete whole memory reserves which would just make - * the situation worse + * the situation worse. */ - page = __alloc_pages_cpuset_fallback(gfp_mask, order, ALLOC_HARDER, ac); + page = __alloc_pages_cpuset_fallback(gfp_mask, order, ALLOC_MIN_RESERVE, ac); if (page) goto got_pg; @@ -4452,39 +4955,38 @@ got_pg: static inline bool prepare_alloc_pages(gfp_t gfp_mask, unsigned int order, int preferred_nid, nodemask_t *nodemask, - struct alloc_context *ac, gfp_t *alloc_mask, + struct alloc_context *ac, gfp_t *alloc_gfp, unsigned int *alloc_flags) { - ac->high_zoneidx = gfp_zone(gfp_mask); + ac->highest_zoneidx = gfp_zone(gfp_mask); ac->zonelist = node_zonelist(preferred_nid, gfp_mask); ac->nodemask = nodemask; - ac->migratetype = gfpflags_to_migratetype(gfp_mask); + ac->migratetype = gfp_migratetype(gfp_mask); if (cpusets_enabled()) { - *alloc_mask |= __GFP_HARDWALL; - if (!ac->nodemask) + *alloc_gfp |= __GFP_HARDWALL; + /* + * When we are in the interrupt context, it is irrelevant + * to the current task context. It means that any node ok. + */ + if (in_task() && !ac->nodemask) ac->nodemask = &cpuset_current_mems_allowed; else *alloc_flags |= ALLOC_CPUSET; } - fs_reclaim_acquire(gfp_mask); - fs_reclaim_release(gfp_mask); - - might_sleep_if(gfp_mask & __GFP_DIRECT_RECLAIM); + might_alloc(gfp_mask); - if (should_fail_alloc_page(gfp_mask, order)) + /* + * Don't invoke should_fail logic, since it may call + * get_random_u32() and printk() which need to spin_lock. + */ + if (!(*alloc_flags & ALLOC_TRYLOCK) && + should_fail_alloc_page(gfp_mask, order)) return false; - if (IS_ENABLED(CONFIG_CMA) && ac->migratetype == MIGRATE_MOVABLE) - *alloc_flags |= ALLOC_CMA; - - return true; -} + *alloc_flags = gfp_to_alloc_flags_cma(gfp_mask, *alloc_flags); -/* Determine whether to spread dirty pages and what the first usable zone */ -static inline void finalise_ac(gfp_t gfp_mask, struct alloc_context *ac) -{ /* Dirty zone balancing only done in the fast path */ ac->spread_dirty_pages = (gfp_mask & __GFP_WRITE); @@ -4494,245 +4996,385 @@ static inline void finalise_ac(gfp_t gfp_mask, struct alloc_context *ac) * may get reset for allocations that ignore memory policies. */ ac->preferred_zoneref = first_zones_zonelist(ac->zonelist, - ac->high_zoneidx, ac->nodemask); + ac->highest_zoneidx, ac->nodemask); + + return true; } /* + * __alloc_pages_bulk - Allocate a number of order-0 pages to an array + * @gfp: GFP flags for the allocation + * @preferred_nid: The preferred NUMA node ID to allocate from + * @nodemask: Set of nodes to allocate from, may be NULL + * @nr_pages: The number of pages desired in the array + * @page_array: Array to store the pages + * + * This is a batched version of the page allocator that attempts to allocate + * @nr_pages quickly. Pages are added to @page_array. + * + * Note that only the elements in @page_array that were cleared to %NULL on + * entry are populated with newly allocated pages. @nr_pages is the maximum + * number of pages that will be stored in the array. + * + * Returns the number of pages in @page_array, including ones already + * allocated on entry. This can be less than the number requested in @nr_pages, + * but all empty slots are filled from the beginning. I.e., if all slots in + * @page_array were set to %NULL on entry, the slots from 0 to the return value + * - 1 will be filled. + */ +unsigned long alloc_pages_bulk_noprof(gfp_t gfp, int preferred_nid, + nodemask_t *nodemask, int nr_pages, + struct page **page_array) +{ + struct page *page; + unsigned long UP_flags; + struct zone *zone; + struct zoneref *z; + struct per_cpu_pages *pcp; + struct list_head *pcp_list; + struct alloc_context ac; + gfp_t alloc_gfp; + unsigned int alloc_flags = ALLOC_WMARK_LOW; + int nr_populated = 0, nr_account = 0; + + /* + * Skip populated array elements to determine if any pages need + * to be allocated before disabling IRQs. + */ + while (nr_populated < nr_pages && page_array[nr_populated]) + nr_populated++; + + /* No pages requested? */ + if (unlikely(nr_pages <= 0)) + goto out; + + /* Already populated array? */ + if (unlikely(nr_pages - nr_populated == 0)) + goto out; + + /* Bulk allocator does not support memcg accounting. */ + if (memcg_kmem_online() && (gfp & __GFP_ACCOUNT)) + goto failed; + + /* Use the single page allocator for one page. */ + if (nr_pages - nr_populated == 1) + goto failed; + +#ifdef CONFIG_PAGE_OWNER + /* + * PAGE_OWNER may recurse into the allocator to allocate space to + * save the stack with pagesets.lock held. Releasing/reacquiring + * removes much of the performance benefit of bulk allocation so + * force the caller to allocate one page at a time as it'll have + * similar performance to added complexity to the bulk allocator. + */ + if (static_branch_unlikely(&page_owner_inited)) + goto failed; +#endif + + /* May set ALLOC_NOFRAGMENT, fragmentation will return 1 page. */ + gfp &= gfp_allowed_mask; + alloc_gfp = gfp; + if (!prepare_alloc_pages(gfp, 0, preferred_nid, nodemask, &ac, &alloc_gfp, &alloc_flags)) + goto out; + gfp = alloc_gfp; + + /* Find an allowed local zone that meets the low watermark. */ + z = ac.preferred_zoneref; + for_next_zone_zonelist_nodemask(zone, z, ac.highest_zoneidx, ac.nodemask) { + unsigned long mark; + + if (cpusets_enabled() && (alloc_flags & ALLOC_CPUSET) && + !__cpuset_zone_allowed(zone, gfp)) { + continue; + } + + if (nr_online_nodes > 1 && zone != zonelist_zone(ac.preferred_zoneref) && + zone_to_nid(zone) != zonelist_node_idx(ac.preferred_zoneref)) { + goto failed; + } + + cond_accept_memory(zone, 0, alloc_flags); +retry_this_zone: + mark = wmark_pages(zone, alloc_flags & ALLOC_WMARK_MASK) + nr_pages; + if (zone_watermark_fast(zone, 0, mark, + zonelist_zone_idx(ac.preferred_zoneref), + alloc_flags, gfp)) { + break; + } + + if (cond_accept_memory(zone, 0, alloc_flags)) + goto retry_this_zone; + + /* Try again if zone has deferred pages */ + if (deferred_pages_enabled()) { + if (_deferred_grow_zone(zone, 0)) + goto retry_this_zone; + } + } + + /* + * If there are no allowed local zones that meets the watermarks then + * try to allocate a single page and reclaim if necessary. + */ + if (unlikely(!zone)) + goto failed; + + /* spin_trylock may fail due to a parallel drain or IRQ reentrancy. */ + pcp = pcp_spin_trylock(zone->per_cpu_pageset, UP_flags); + if (!pcp) + goto failed; + + /* Attempt the batch allocation */ + pcp_list = &pcp->lists[order_to_pindex(ac.migratetype, 0)]; + while (nr_populated < nr_pages) { + + /* Skip existing pages */ + if (page_array[nr_populated]) { + nr_populated++; + continue; + } + + page = __rmqueue_pcplist(zone, 0, ac.migratetype, alloc_flags, + pcp, pcp_list); + if (unlikely(!page)) { + /* Try and allocate at least one page */ + if (!nr_account) { + pcp_spin_unlock(pcp, UP_flags); + goto failed; + } + break; + } + nr_account++; + + prep_new_page(page, 0, gfp, 0); + set_page_refcounted(page); + page_array[nr_populated++] = page; + } + + pcp_spin_unlock(pcp, UP_flags); + + __count_zid_vm_events(PGALLOC, zone_idx(zone), nr_account); + zone_statistics(zonelist_zone(ac.preferred_zoneref), zone, nr_account); + +out: + return nr_populated; + +failed: + page = __alloc_pages_noprof(gfp, 0, preferred_nid, nodemask); + if (page) + page_array[nr_populated++] = page; + goto out; +} +EXPORT_SYMBOL_GPL(alloc_pages_bulk_noprof); + +/* * This is the 'heart' of the zoned buddy allocator. */ -struct page * -__alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order, int preferred_nid, - nodemask_t *nodemask) +struct page *__alloc_frozen_pages_noprof(gfp_t gfp, unsigned int order, + int preferred_nid, nodemask_t *nodemask) { struct page *page; unsigned int alloc_flags = ALLOC_WMARK_LOW; - gfp_t alloc_mask; /* The gfp_t that was actually used for allocation */ + gfp_t alloc_gfp; /* The gfp_t that was actually used for allocation */ struct alloc_context ac = { }; /* * There are several places where we assume that the order value is sane * so bail out early if the request is out of bound. */ - if (unlikely(order >= MAX_ORDER)) { - WARN_ON_ONCE(!(gfp_mask & __GFP_NOWARN)); + if (WARN_ON_ONCE_GFP(order > MAX_PAGE_ORDER, gfp)) return NULL; - } - gfp_mask &= gfp_allowed_mask; - alloc_mask = gfp_mask; - if (!prepare_alloc_pages(gfp_mask, order, preferred_nid, nodemask, &ac, &alloc_mask, &alloc_flags)) + gfp &= gfp_allowed_mask; + /* + * Apply scoped allocation constraints. This is mainly about GFP_NOFS + * resp. GFP_NOIO which has to be inherited for all allocation requests + * from a particular context which has been marked by + * memalloc_no{fs,io}_{save,restore}. And PF_MEMALLOC_PIN which ensures + * movable zones are not used during allocation. + */ + gfp = current_gfp_context(gfp); + alloc_gfp = gfp; + if (!prepare_alloc_pages(gfp, order, preferred_nid, nodemask, &ac, + &alloc_gfp, &alloc_flags)) return NULL; - finalise_ac(gfp_mask, &ac); - /* * Forbid the first pass from falling back to types that fragment * memory until all local zones are considered. */ - alloc_flags |= alloc_flags_nofragment(ac.preferred_zoneref->zone, gfp_mask); + alloc_flags |= alloc_flags_nofragment(zonelist_zone(ac.preferred_zoneref), gfp); /* First allocation attempt */ - page = get_page_from_freelist(alloc_mask, order, alloc_flags, &ac); + page = get_page_from_freelist(alloc_gfp, order, alloc_flags, &ac); if (likely(page)) goto out; - /* - * Apply scoped allocation constraints. This is mainly about GFP_NOFS - * resp. GFP_NOIO which has to be inherited for all allocation requests - * from a particular context which has been marked by - * memalloc_no{fs,io}_{save,restore}. - */ - alloc_mask = current_gfp_context(gfp_mask); + alloc_gfp = gfp; ac.spread_dirty_pages = false; /* * Restore the original nodemask if it was potentially replaced with * &cpuset_current_mems_allowed to optimize the fast-path attempt. */ - if (unlikely(ac.nodemask != nodemask)) - ac.nodemask = nodemask; + ac.nodemask = nodemask; - page = __alloc_pages_slowpath(alloc_mask, order, &ac); + page = __alloc_pages_slowpath(alloc_gfp, order, &ac); out: - if (memcg_kmem_enabled() && (gfp_mask & __GFP_ACCOUNT) && page && - unlikely(memcg_kmem_charge(page, gfp_mask, order) != 0)) { - __free_pages(page, order); + if (memcg_kmem_online() && (gfp & __GFP_ACCOUNT) && page && + unlikely(__memcg_kmem_charge_page(page, gfp, order) != 0)) { + free_frozen_pages(page, order); page = NULL; } - trace_mm_page_alloc(page, order, alloc_mask, ac.migratetype); + trace_mm_page_alloc(page, order, alloc_gfp, ac.migratetype); + kmsan_alloc_page(page, order, alloc_gfp); return page; } -EXPORT_SYMBOL(__alloc_pages_nodemask); +EXPORT_SYMBOL(__alloc_frozen_pages_noprof); + +struct page *__alloc_pages_noprof(gfp_t gfp, unsigned int order, + int preferred_nid, nodemask_t *nodemask) +{ + struct page *page; + + page = __alloc_frozen_pages_noprof(gfp, order, preferred_nid, nodemask); + if (page) + set_page_refcounted(page); + return page; +} +EXPORT_SYMBOL(__alloc_pages_noprof); + +struct folio *__folio_alloc_noprof(gfp_t gfp, unsigned int order, int preferred_nid, + nodemask_t *nodemask) +{ + struct page *page = __alloc_pages_noprof(gfp | __GFP_COMP, order, + preferred_nid, nodemask); + return page_rmappable_folio(page); +} +EXPORT_SYMBOL(__folio_alloc_noprof); /* * Common helper functions. Never use with __GFP_HIGHMEM because the returned * address cannot represent highmem pages. Use alloc_pages and then kmap if * you need to access high mem. */ -unsigned long __get_free_pages(gfp_t gfp_mask, unsigned int order) +unsigned long get_free_pages_noprof(gfp_t gfp_mask, unsigned int order) { struct page *page; - page = alloc_pages(gfp_mask & ~__GFP_HIGHMEM, order); + page = alloc_pages_noprof(gfp_mask & ~__GFP_HIGHMEM, order); if (!page) return 0; return (unsigned long) page_address(page); } -EXPORT_SYMBOL(__get_free_pages); +EXPORT_SYMBOL(get_free_pages_noprof); -unsigned long get_zeroed_page(gfp_t gfp_mask) +unsigned long get_zeroed_page_noprof(gfp_t gfp_mask) { - return __get_free_pages(gfp_mask | __GFP_ZERO, 0); + return get_free_pages_noprof(gfp_mask | __GFP_ZERO, 0); } -EXPORT_SYMBOL(get_zeroed_page); +EXPORT_SYMBOL(get_zeroed_page_noprof); -static inline void free_the_page(struct page *page, unsigned int order) +static void ___free_pages(struct page *page, unsigned int order, + fpi_t fpi_flags) { - if (order == 0) /* Via pcp? */ - free_unref_page(page); - else - __free_pages_ok(page, order); -} + /* get PageHead before we drop reference */ + int head = PageHead(page); + /* get alloc tag in case the page is released by others */ + struct alloc_tag *tag = pgalloc_tag_get(page); -void __free_pages(struct page *page, unsigned int order) -{ if (put_page_testzero(page)) - free_the_page(page, order); -} -EXPORT_SYMBOL(__free_pages); - -void free_pages(unsigned long addr, unsigned int order) -{ - if (addr != 0) { - VM_BUG_ON(!virt_addr_valid((void *)addr)); - __free_pages(virt_to_page((void *)addr), order); + __free_frozen_pages(page, order, fpi_flags); + else if (!head) { + pgalloc_tag_sub_pages(tag, (1 << order) - 1); + while (order-- > 0) { + /* + * The "tail" pages of this non-compound high-order + * page will have no code tags, so to avoid warnings + * mark them as empty. + */ + clear_page_tag_ref(page + (1 << order)); + __free_frozen_pages(page + (1 << order), order, + fpi_flags); + } } } -EXPORT_SYMBOL(free_pages); - -/* - * Page Fragment: - * An arbitrary-length arbitrary-offset area of memory which resides - * within a 0 or higher order page. Multiple fragments within that page - * are individually refcounted, in the page's reference counter. +/** + * __free_pages - Free pages allocated with alloc_pages(). + * @page: The page pointer returned from alloc_pages(). + * @order: The order of the allocation. * - * The page_frag functions below provide a simple allocation framework for - * page fragments. This is used by the network stack and network device - * drivers to provide a backing region of memory for use as either an - * sk_buff->head, or to be used in the "frags" portion of skb_shared_info. + * This function can free multi-page allocations that are not compound + * pages. It does not check that the @order passed in matches that of + * the allocation, so it is easy to leak memory. Freeing more memory + * than was allocated will probably emit a warning. + * + * If the last reference to this page is speculative, it will be released + * by put_page() which only frees the first page of a non-compound + * allocation. To prevent the remaining pages from being leaked, we free + * the subsequent pages here. If you want to use the page's reference + * count to decide when to free the allocation, you should allocate a + * compound page, and use put_page() instead of __free_pages(). + * + * Context: May be called in interrupt context or while holding a normal + * spinlock, but not in NMI context or while holding a raw spinlock. */ -static struct page *__page_frag_cache_refill(struct page_frag_cache *nc, - gfp_t gfp_mask) +void __free_pages(struct page *page, unsigned int order) { - struct page *page = NULL; - gfp_t gfp = gfp_mask; - -#if (PAGE_SIZE < PAGE_FRAG_CACHE_MAX_SIZE) - gfp_mask |= __GFP_COMP | __GFP_NOWARN | __GFP_NORETRY | - __GFP_NOMEMALLOC; - page = alloc_pages_node(NUMA_NO_NODE, gfp_mask, - PAGE_FRAG_CACHE_MAX_ORDER); - nc->size = page ? PAGE_FRAG_CACHE_MAX_SIZE : PAGE_SIZE; -#endif - if (unlikely(!page)) - page = alloc_pages_node(NUMA_NO_NODE, gfp, 0); - - nc->va = page ? page_address(page) : NULL; - - return page; + ___free_pages(page, order, FPI_NONE); } +EXPORT_SYMBOL(__free_pages); -void __page_frag_cache_drain(struct page *page, unsigned int count) +/* + * Can be called while holding raw_spin_lock or from IRQ and NMI for any + * page type (not only those that came from alloc_pages_nolock) + */ +void free_pages_nolock(struct page *page, unsigned int order) { - VM_BUG_ON_PAGE(page_ref_count(page) == 0, page); - - if (page_ref_sub_and_test(page, count)) - free_the_page(page, compound_order(page)); + ___free_pages(page, order, FPI_TRYLOCK); } -EXPORT_SYMBOL(__page_frag_cache_drain); -void *page_frag_alloc(struct page_frag_cache *nc, - unsigned int fragsz, gfp_t gfp_mask) +/** + * free_pages - Free pages allocated with __get_free_pages(). + * @addr: The virtual address tied to a page returned from __get_free_pages(). + * @order: The order of the allocation. + * + * This function behaves the same as __free_pages(). Use this function + * to free pages when you only have a valid virtual address. If you have + * the page, call __free_pages() instead. + */ +void free_pages(unsigned long addr, unsigned int order) { - unsigned int size = PAGE_SIZE; - struct page *page; - int offset; - - if (unlikely(!nc->va)) { -refill: - page = __page_frag_cache_refill(nc, gfp_mask); - if (!page) - return NULL; - -#if (PAGE_SIZE < PAGE_FRAG_CACHE_MAX_SIZE) - /* if size can vary use size else just use PAGE_SIZE */ - size = nc->size; -#endif - /* Even if we own the page, we do not use atomic_set(). - * This would break get_page_unless_zero() users. - */ - page_ref_add(page, size - 1); - - /* reset page count bias and offset to start of new frag */ - nc->pfmemalloc = page_is_pfmemalloc(page); - nc->pagecnt_bias = size; - nc->offset = size; - } - - offset = nc->offset - fragsz; - if (unlikely(offset < 0)) { - page = virt_to_page(nc->va); - - if (!page_ref_sub_and_test(page, nc->pagecnt_bias)) - goto refill; - -#if (PAGE_SIZE < PAGE_FRAG_CACHE_MAX_SIZE) - /* if size can vary use size else just use PAGE_SIZE */ - size = nc->size; -#endif - /* OK, page count is 0, we can safely set it */ - set_page_count(page, size); - - /* reset page count bias and offset to start of new frag */ - nc->pagecnt_bias = size; - offset = size - fragsz; + if (addr != 0) { + VM_BUG_ON(!virt_addr_valid((void *)addr)); + __free_pages(virt_to_page((void *)addr), order); } - - nc->pagecnt_bias--; - nc->offset = offset; - - return nc->va + offset; } -EXPORT_SYMBOL(page_frag_alloc); -/* - * Frees a page fragment allocated out of either a compound or order 0 page. - */ -void page_frag_free(void *addr) -{ - struct page *page = virt_to_head_page(addr); - - if (unlikely(put_page_testzero(page))) - free_the_page(page, compound_order(page)); -} -EXPORT_SYMBOL(page_frag_free); +EXPORT_SYMBOL(free_pages); static void *make_alloc_exact(unsigned long addr, unsigned int order, size_t size) { if (addr) { - unsigned long alloc_end = addr + (PAGE_SIZE << order); - unsigned long used = addr + PAGE_ALIGN(size); + unsigned long nr = DIV_ROUND_UP(size, PAGE_SIZE); + struct page *page = virt_to_page((void *)addr); + struct page *last = page + nr; - split_page(virt_to_page((void *)addr), order); - while (used < alloc_end) { - free_page(used); - used += PAGE_SIZE; - } + split_page_owner(page, order, 0); + pgalloc_tag_split(page_folio(page), order, 0); + split_page_memcg(page, order); + while (page < --last) + set_page_refcounted(last); + + last = page + (1UL << order); + for (page += nr; page < last; page++) + __free_pages_ok(page, 0, FPI_TO_TAIL); } return (void *)addr; } @@ -4740,40 +5382,52 @@ static void *make_alloc_exact(unsigned long addr, unsigned int order, /** * alloc_pages_exact - allocate an exact number physically-contiguous pages. * @size: the number of bytes to allocate - * @gfp_mask: GFP flags for the allocation + * @gfp_mask: GFP flags for the allocation, must not contain __GFP_COMP * * This function is similar to alloc_pages(), except that it allocates the * minimum number of pages to satisfy the request. alloc_pages() can only * allocate memory in power-of-two pages. * - * This function is also limited by MAX_ORDER. + * This function is also limited by MAX_PAGE_ORDER. * * Memory allocated by this function must be released by free_pages_exact(). + * + * Return: pointer to the allocated area or %NULL in case of error. */ -void *alloc_pages_exact(size_t size, gfp_t gfp_mask) +void *alloc_pages_exact_noprof(size_t size, gfp_t gfp_mask) { unsigned int order = get_order(size); unsigned long addr; - addr = __get_free_pages(gfp_mask, order); + if (WARN_ON_ONCE(gfp_mask & (__GFP_COMP | __GFP_HIGHMEM))) + gfp_mask &= ~(__GFP_COMP | __GFP_HIGHMEM); + + addr = get_free_pages_noprof(gfp_mask, order); return make_alloc_exact(addr, order, size); } -EXPORT_SYMBOL(alloc_pages_exact); +EXPORT_SYMBOL(alloc_pages_exact_noprof); /** * alloc_pages_exact_nid - allocate an exact number of physically-contiguous * pages on a node. * @nid: the preferred node ID where memory should be allocated * @size: the number of bytes to allocate - * @gfp_mask: GFP flags for the allocation + * @gfp_mask: GFP flags for the allocation, must not contain __GFP_COMP * * Like alloc_pages_exact(), but try to allocate on node nid first before falling * back. + * + * Return: pointer to the allocated area or %NULL in case of error. */ -void * __meminit alloc_pages_exact_nid(int nid, size_t size, gfp_t gfp_mask) +void * __meminit alloc_pages_exact_nid_noprof(int nid, size_t size, gfp_t gfp_mask) { unsigned int order = get_order(size); - struct page *p = alloc_pages_node(nid, gfp_mask, order); + struct page *p; + + if (WARN_ON_ONCE(gfp_mask & (__GFP_COMP | __GFP_HIGHMEM))) + gfp_mask &= ~(__GFP_COMP | __GFP_HIGHMEM); + + p = alloc_pages_node_noprof(nid, gfp_mask, order); if (!p) return NULL; return make_alloc_exact((unsigned long)page_address(p), order, size); @@ -4802,11 +5456,13 @@ EXPORT_SYMBOL(free_pages_exact); * nr_free_zone_pages - count number of pages beyond high watermark * @offset: The zone index of the highest zone * - * nr_free_zone_pages() counts the number of counts pages which are beyond the + * nr_free_zone_pages() counts the number of pages which are beyond the * high watermark within all zones at or below a given zone index. For each * zone, the number of pages is calculated as: * * nr_free_zone_pages = managed_pages - high_pages + * + * Return: number of pages beyond high watermark. */ static unsigned long nr_free_zone_pages(int offset) { @@ -4833,6 +5489,9 @@ static unsigned long nr_free_zone_pages(int offset) * * nr_free_buffer_pages() counts the number of pages which are beyond the high * watermark within ZONE_DMA and ZONE_NORMAL. + * + * Return: number of pages beyond high watermark within ZONE_DMA and + * ZONE_NORMAL. */ unsigned long nr_free_buffer_pages(void) { @@ -4840,363 +5499,6 @@ unsigned long nr_free_buffer_pages(void) } EXPORT_SYMBOL_GPL(nr_free_buffer_pages); -/** - * nr_free_pagecache_pages - count number of pages beyond high watermark - * - * nr_free_pagecache_pages() counts the number of pages which are beyond the - * high watermark within all zones. - */ -unsigned long nr_free_pagecache_pages(void) -{ - return nr_free_zone_pages(gfp_zone(GFP_HIGHUSER_MOVABLE)); -} - -static inline void show_node(struct zone *zone) -{ - if (IS_ENABLED(CONFIG_NUMA)) - printk("Node %d ", zone_to_nid(zone)); -} - -long si_mem_available(void) -{ - long available; - unsigned long pagecache; - unsigned long wmark_low = 0; - unsigned long pages[NR_LRU_LISTS]; - unsigned long reclaimable; - struct zone *zone; - int lru; - - for (lru = LRU_BASE; lru < NR_LRU_LISTS; lru++) - pages[lru] = global_node_page_state(NR_LRU_BASE + lru); - - for_each_zone(zone) - wmark_low += low_wmark_pages(zone); - - /* - * Estimate the amount of memory available for userspace allocations, - * without causing swapping. - */ - available = global_zone_page_state(NR_FREE_PAGES) - totalreserve_pages; - - /* - * Not all the page cache can be freed, otherwise the system will - * start swapping. Assume at least half of the page cache, or the - * low watermark worth of cache, needs to stay. - */ - pagecache = pages[LRU_ACTIVE_FILE] + pages[LRU_INACTIVE_FILE]; - pagecache -= min(pagecache / 2, wmark_low); - available += pagecache; - - /* - * Part of the reclaimable slab and other kernel memory consists of - * items that are in use, and cannot be freed. Cap this estimate at the - * low watermark. - */ - reclaimable = global_node_page_state(NR_SLAB_RECLAIMABLE) + - global_node_page_state(NR_KERNEL_MISC_RECLAIMABLE); - available += reclaimable - min(reclaimable / 2, wmark_low); - - if (available < 0) - available = 0; - return available; -} -EXPORT_SYMBOL_GPL(si_mem_available); - -void si_meminfo(struct sysinfo *val) -{ - val->totalram = totalram_pages(); - val->sharedram = global_node_page_state(NR_SHMEM); - val->freeram = global_zone_page_state(NR_FREE_PAGES); - val->bufferram = nr_blockdev_pages(); - val->totalhigh = totalhigh_pages(); - val->freehigh = nr_free_highpages(); - val->mem_unit = PAGE_SIZE; -} - -EXPORT_SYMBOL(si_meminfo); - -#ifdef CONFIG_NUMA -void si_meminfo_node(struct sysinfo *val, int nid) -{ - int zone_type; /* needs to be signed */ - unsigned long managed_pages = 0; - unsigned long managed_highpages = 0; - unsigned long free_highpages = 0; - pg_data_t *pgdat = NODE_DATA(nid); - - for (zone_type = 0; zone_type < MAX_NR_ZONES; zone_type++) - managed_pages += zone_managed_pages(&pgdat->node_zones[zone_type]); - val->totalram = managed_pages; - val->sharedram = node_page_state(pgdat, NR_SHMEM); - val->freeram = sum_zone_node_page_state(nid, NR_FREE_PAGES); -#ifdef CONFIG_HIGHMEM - for (zone_type = 0; zone_type < MAX_NR_ZONES; zone_type++) { - struct zone *zone = &pgdat->node_zones[zone_type]; - - if (is_highmem(zone)) { - managed_highpages += zone_managed_pages(zone); - free_highpages += zone_page_state(zone, NR_FREE_PAGES); - } - } - val->totalhigh = managed_highpages; - val->freehigh = free_highpages; -#else - val->totalhigh = managed_highpages; - val->freehigh = free_highpages; -#endif - val->mem_unit = PAGE_SIZE; -} -#endif - -/* - * Determine whether the node should be displayed or not, depending on whether - * SHOW_MEM_FILTER_NODES was passed to show_free_areas(). - */ -static bool show_mem_node_skip(unsigned int flags, int nid, nodemask_t *nodemask) -{ - if (!(flags & SHOW_MEM_FILTER_NODES)) - return false; - - /* - * no node mask - aka implicit memory numa policy. Do not bother with - * the synchronization - read_mems_allowed_begin - because we do not - * have to be precise here. - */ - if (!nodemask) - nodemask = &cpuset_current_mems_allowed; - - return !node_isset(nid, *nodemask); -} - -#define K(x) ((x) << (PAGE_SHIFT-10)) - -static void show_migration_types(unsigned char type) -{ - static const char types[MIGRATE_TYPES] = { - [MIGRATE_UNMOVABLE] = 'U', - [MIGRATE_MOVABLE] = 'M', - [MIGRATE_RECLAIMABLE] = 'E', - [MIGRATE_HIGHATOMIC] = 'H', -#ifdef CONFIG_CMA - [MIGRATE_CMA] = 'C', -#endif -#ifdef CONFIG_MEMORY_ISOLATION - [MIGRATE_ISOLATE] = 'I', -#endif - }; - char tmp[MIGRATE_TYPES + 1]; - char *p = tmp; - int i; - - for (i = 0; i < MIGRATE_TYPES; i++) { - if (type & (1 << i)) - *p++ = types[i]; - } - - *p = '\0'; - printk(KERN_CONT "(%s) ", tmp); -} - -/* - * Show free area list (used inside shift_scroll-lock stuff) - * We also calculate the percentage fragmentation. We do this by counting the - * memory on each free list with the exception of the first item on the list. - * - * Bits in @filter: - * SHOW_MEM_FILTER_NODES: suppress nodes that are not allowed by current's - * cpuset. - */ -void show_free_areas(unsigned int filter, nodemask_t *nodemask) -{ - unsigned long free_pcp = 0; - int cpu; - struct zone *zone; - pg_data_t *pgdat; - - for_each_populated_zone(zone) { - if (show_mem_node_skip(filter, zone_to_nid(zone), nodemask)) - continue; - - for_each_online_cpu(cpu) - free_pcp += per_cpu_ptr(zone->pageset, cpu)->pcp.count; - } - - printk("active_anon:%lu inactive_anon:%lu isolated_anon:%lu\n" - " active_file:%lu inactive_file:%lu isolated_file:%lu\n" - " unevictable:%lu dirty:%lu writeback:%lu unstable:%lu\n" - " slab_reclaimable:%lu slab_unreclaimable:%lu\n" - " mapped:%lu shmem:%lu pagetables:%lu bounce:%lu\n" - " free:%lu free_pcp:%lu free_cma:%lu\n", - global_node_page_state(NR_ACTIVE_ANON), - global_node_page_state(NR_INACTIVE_ANON), - global_node_page_state(NR_ISOLATED_ANON), - global_node_page_state(NR_ACTIVE_FILE), - global_node_page_state(NR_INACTIVE_FILE), - global_node_page_state(NR_ISOLATED_FILE), - global_node_page_state(NR_UNEVICTABLE), - global_node_page_state(NR_FILE_DIRTY), - global_node_page_state(NR_WRITEBACK), - global_node_page_state(NR_UNSTABLE_NFS), - global_node_page_state(NR_SLAB_RECLAIMABLE), - global_node_page_state(NR_SLAB_UNRECLAIMABLE), - global_node_page_state(NR_FILE_MAPPED), - global_node_page_state(NR_SHMEM), - global_zone_page_state(NR_PAGETABLE), - global_zone_page_state(NR_BOUNCE), - global_zone_page_state(NR_FREE_PAGES), - free_pcp, - global_zone_page_state(NR_FREE_CMA_PAGES)); - - for_each_online_pgdat(pgdat) { - if (show_mem_node_skip(filter, pgdat->node_id, nodemask)) - continue; - - printk("Node %d" - " active_anon:%lukB" - " inactive_anon:%lukB" - " active_file:%lukB" - " inactive_file:%lukB" - " unevictable:%lukB" - " isolated(anon):%lukB" - " isolated(file):%lukB" - " mapped:%lukB" - " dirty:%lukB" - " writeback:%lukB" - " shmem:%lukB" -#ifdef CONFIG_TRANSPARENT_HUGEPAGE - " shmem_thp: %lukB" - " shmem_pmdmapped: %lukB" - " anon_thp: %lukB" -#endif - " writeback_tmp:%lukB" - " unstable:%lukB" - " all_unreclaimable? %s" - "\n", - pgdat->node_id, - K(node_page_state(pgdat, NR_ACTIVE_ANON)), - K(node_page_state(pgdat, NR_INACTIVE_ANON)), - K(node_page_state(pgdat, NR_ACTIVE_FILE)), - K(node_page_state(pgdat, NR_INACTIVE_FILE)), - K(node_page_state(pgdat, NR_UNEVICTABLE)), - K(node_page_state(pgdat, NR_ISOLATED_ANON)), - K(node_page_state(pgdat, NR_ISOLATED_FILE)), - K(node_page_state(pgdat, NR_FILE_MAPPED)), - K(node_page_state(pgdat, NR_FILE_DIRTY)), - K(node_page_state(pgdat, NR_WRITEBACK)), - K(node_page_state(pgdat, NR_SHMEM)), -#ifdef CONFIG_TRANSPARENT_HUGEPAGE - K(node_page_state(pgdat, NR_SHMEM_THPS) * HPAGE_PMD_NR), - K(node_page_state(pgdat, NR_SHMEM_PMDMAPPED) - * HPAGE_PMD_NR), - K(node_page_state(pgdat, NR_ANON_THPS) * HPAGE_PMD_NR), -#endif - K(node_page_state(pgdat, NR_WRITEBACK_TEMP)), - K(node_page_state(pgdat, NR_UNSTABLE_NFS)), - pgdat->kswapd_failures >= MAX_RECLAIM_RETRIES ? - "yes" : "no"); - } - - for_each_populated_zone(zone) { - int i; - - if (show_mem_node_skip(filter, zone_to_nid(zone), nodemask)) - continue; - - free_pcp = 0; - for_each_online_cpu(cpu) - free_pcp += per_cpu_ptr(zone->pageset, cpu)->pcp.count; - - show_node(zone); - printk(KERN_CONT - "%s" - " free:%lukB" - " min:%lukB" - " low:%lukB" - " high:%lukB" - " active_anon:%lukB" - " inactive_anon:%lukB" - " active_file:%lukB" - " inactive_file:%lukB" - " unevictable:%lukB" - " writepending:%lukB" - " present:%lukB" - " managed:%lukB" - " mlocked:%lukB" - " kernel_stack:%lukB" - " pagetables:%lukB" - " bounce:%lukB" - " free_pcp:%lukB" - " local_pcp:%ukB" - " free_cma:%lukB" - "\n", - zone->name, - K(zone_page_state(zone, NR_FREE_PAGES)), - K(min_wmark_pages(zone)), - K(low_wmark_pages(zone)), - K(high_wmark_pages(zone)), - K(zone_page_state(zone, NR_ZONE_ACTIVE_ANON)), - K(zone_page_state(zone, NR_ZONE_INACTIVE_ANON)), - K(zone_page_state(zone, NR_ZONE_ACTIVE_FILE)), - K(zone_page_state(zone, NR_ZONE_INACTIVE_FILE)), - K(zone_page_state(zone, NR_ZONE_UNEVICTABLE)), - K(zone_page_state(zone, NR_ZONE_WRITE_PENDING)), - K(zone->present_pages), - K(zone_managed_pages(zone)), - K(zone_page_state(zone, NR_MLOCK)), - zone_page_state(zone, NR_KERNEL_STACK_KB), - K(zone_page_state(zone, NR_PAGETABLE)), - K(zone_page_state(zone, NR_BOUNCE)), - K(free_pcp), - K(this_cpu_read(zone->pageset->pcp.count)), - K(zone_page_state(zone, NR_FREE_CMA_PAGES))); - printk("lowmem_reserve[]:"); - for (i = 0; i < MAX_NR_ZONES; i++) - printk(KERN_CONT " %ld", zone->lowmem_reserve[i]); - printk(KERN_CONT "\n"); - } - - for_each_populated_zone(zone) { - unsigned int order; - unsigned long nr[MAX_ORDER], flags, total = 0; - unsigned char types[MAX_ORDER]; - - if (show_mem_node_skip(filter, zone_to_nid(zone), nodemask)) - continue; - show_node(zone); - printk(KERN_CONT "%s: ", zone->name); - - spin_lock_irqsave(&zone->lock, flags); - for (order = 0; order < MAX_ORDER; order++) { - struct free_area *area = &zone->free_area[order]; - int type; - - nr[order] = area->nr_free; - total += nr[order] << order; - - types[order] = 0; - for (type = 0; type < MIGRATE_TYPES; type++) { - if (!list_empty(&area->free_list[type])) - types[order] |= 1 << type; - } - } - spin_unlock_irqrestore(&zone->lock, flags); - for (order = 0; order < MAX_ORDER; order++) { - printk(KERN_CONT "%lu*%lukB ", - nr[order], K(1UL) << order); - if (nr[order]) - show_migration_types(types[order]); - } - printk(KERN_CONT "= %lukB\n", K(total)); - } - - hugetlb_show_meminfo(); - - printk("%ld total pagecache pages\n", global_node_page_state(NR_FILE_PAGES)); - - show_swap_cache_info(); -} - static void zoneref_set_zone(struct zone *zone, struct zoneref *zoneref) { zoneref->zone = zone; @@ -5217,7 +5519,7 @@ static int build_zonerefs_node(pg_data_t *pgdat, struct zoneref *zonerefs) do { zone_type--; zone = pgdat->node_zones + zone_type; - if (managed_zone(zone)) { + if (populated_zone(zone)) { zoneref_set_zone(zone, &zonerefs[nr_zones++]); check_highest_zone(zone_type); } @@ -5231,7 +5533,7 @@ static int build_zonerefs_node(pg_data_t *pgdat, struct zoneref *zonerefs) static int __parse_numa_zonelist_order(char *s) { /* - * We used to support different zonlists modes but they turned + * We used to support different zonelists modes but they turned * out to be just not useful. Let's keep the warning in place * if somebody still use the cmd line parameter so that we do * not fail it silently @@ -5243,40 +5545,19 @@ static int __parse_numa_zonelist_order(char *s) return 0; } -static __init int setup_numa_zonelist_order(char *s) -{ - if (!s) - return 0; - - return __parse_numa_zonelist_order(s); -} -early_param("numa_zonelist_order", setup_numa_zonelist_order); - -char numa_zonelist_order[] = "Node"; - +static char numa_zonelist_order[] = "Node"; +#define NUMA_ZONELIST_ORDER_LEN 16 /* * sysctl handler for numa_zonelist_order */ -int numa_zonelist_order_handler(struct ctl_table *table, int write, - void __user *buffer, size_t *length, - loff_t *ppos) +static int numa_zonelist_order_handler(const struct ctl_table *table, int write, + void *buffer, size_t *length, loff_t *ppos) { - char *str; - int ret; - - if (!write) - return proc_dostring(table, write, buffer, length, ppos); - str = memdup_user_nul(buffer, 16); - if (IS_ERR(str)) - return PTR_ERR(str); - - ret = __parse_numa_zonelist_order(str); - kfree(str); - return ret; + if (write) + return __parse_numa_zonelist_order(buffer); + return proc_dostring(table, write, buffer, length, ppos); } - -#define MAX_NODE_LOAD (nr_online_nodes) static int node_load[MAX_NUMNODES]; /** @@ -5291,17 +5572,20 @@ static int node_load[MAX_NUMNODES]; * from each node to each node in the system), and should also prefer nodes * with no CPUs, since presumably they'll have very little allocation pressure * on them otherwise. - * It returns -1 if no node is found. + * + * Return: node id of the found node or %NUMA_NO_NODE if no node is found. */ -static int find_next_best_node(int node, nodemask_t *used_node_mask) +int find_next_best_node(int node, nodemask_t *used_node_mask) { int n, val; int min_val = INT_MAX; int best_node = NUMA_NO_NODE; - const struct cpumask *tmp = cpumask_of_node(0); - /* Use the local node if we haven't already */ - if (!node_isset(node, *used_node_mask)) { + /* + * Use the local node if we haven't already, but for memoryless local + * node, we should skip it and fall back to other nodes. + */ + if (!node_isset(node, *used_node_mask) && node_state(node, N_MEMORY)) { node_set(node, *used_node_mask); return node; } @@ -5319,12 +5603,11 @@ static int find_next_best_node(int node, nodemask_t *used_node_mask) val += (n < node); /* Give preference to headless and unused nodes */ - tmp = cpumask_of_node(n); - if (!cpumask_empty(tmp)) + if (!cpumask_empty(cpumask_of_node(n))) val += PENALTY_FOR_NODE_WITH_CPUS; /* Slight preference for less loaded node */ - val *= (MAX_NODE_LOAD*MAX_NUMNODES); + val *= MAX_NUMNODES; val += node_load[n]; if (val < min_val) { @@ -5366,7 +5649,7 @@ static void build_zonelists_in_node_order(pg_data_t *pgdat, int *node_order, } /* - * Build gfp_thisnode zonelists + * Build __GFP_THISNODE zonelists */ static void build_thisnode_zonelists(pg_data_t *pgdat) { @@ -5380,25 +5663,16 @@ static void build_thisnode_zonelists(pg_data_t *pgdat) zonerefs->zone_idx = 0; } -/* - * Build zonelists ordered by zone and nodes within zones. - * This results in conserving DMA zone[s] until all Normal memory is - * exhausted, but results in overflowing to remote node while memory - * may still exist in local DMA zone. - */ - static void build_zonelists(pg_data_t *pgdat) { static int node_order[MAX_NUMNODES]; - int node, load, nr_nodes = 0; - nodemask_t used_mask; + int node, nr_nodes = 0; + nodemask_t used_mask = NODE_MASK_NONE; int local_node, prev_node; /* NUMA-aware ordering of nodes */ local_node = pgdat->node_id; - load = nr_online_nodes; prev_node = local_node; - nodes_clear(used_mask); memset(node_order, 0, sizeof(node_order)); while ((node = find_next_best_node(local_node, &used_mask)) >= 0) { @@ -5409,15 +5683,18 @@ static void build_zonelists(pg_data_t *pgdat) */ if (node_distance(local_node, node) != node_distance(local_node, prev_node)) - node_load[node] = load; + node_load[node] += 1; node_order[nr_nodes++] = node; prev_node = node; - load--; } build_zonelists_in_node_order(pgdat, node_order, nr_nodes); build_thisnode_zonelists(pgdat); + pr_info("Fallback order for Node %d: ", local_node); + for (node = 0; node < nr_nodes; node++) + pr_cont("%d ", node_order[node]); + pr_cont("\n"); } #ifdef CONFIG_HAVE_MEMORYLESS_NODES @@ -5434,7 +5711,7 @@ int local_memory_node(int node) z = first_zones_zonelist(node_zonelist(node, GFP_KERNEL), gfp_zone(GFP_KERNEL), NULL); - return zone_to_nid(z->zone); + return zonelist_node_idx(z); } #endif @@ -5444,37 +5721,13 @@ static void setup_min_slab_ratio(void); static void build_zonelists(pg_data_t *pgdat) { - int node, local_node; struct zoneref *zonerefs; int nr_zones; - local_node = pgdat->node_id; - zonerefs = pgdat->node_zonelists[ZONELIST_FALLBACK]._zonerefs; nr_zones = build_zonerefs_node(pgdat, zonerefs); zonerefs += nr_zones; - /* - * Now we build the zonelist so that it contains the zones - * of all the other nodes. - * We don't want to pressure a particular node, so when - * building the zones for node N, we make sure that the - * zones coming right after the local ones are those from - * node N+1 (modulo N) - */ - for (node = local_node + 1; node < MAX_NUMNODES; node++) { - if (!node_online(node)) - continue; - nr_zones = build_zonerefs_node(NODE_DATA(node), zonerefs); - zonerefs += nr_zones; - } - for (node = 0; node < local_node; node++) { - if (!node_online(node)) - continue; - nr_zones = build_zonerefs_node(NODE_DATA(node), zonerefs); - zonerefs += nr_zones; - } - zonerefs->zone = NULL; zonerefs->zone_idx = 0; } @@ -5496,18 +5749,32 @@ static void build_zonelists(pg_data_t *pgdat) * not check if the processor is online before following the pageset pointer. * Other parts of the kernel may not check if the zone is available. */ -static void setup_pageset(struct per_cpu_pageset *p, unsigned long batch); -static DEFINE_PER_CPU(struct per_cpu_pageset, boot_pageset); -static DEFINE_PER_CPU(struct per_cpu_nodestat, boot_nodestats); +static void per_cpu_pages_init(struct per_cpu_pages *pcp, struct per_cpu_zonestat *pzstats); +/* These effectively disable the pcplists in the boot pageset completely */ +#define BOOT_PAGESET_HIGH 0 +#define BOOT_PAGESET_BATCH 1 +static DEFINE_PER_CPU(struct per_cpu_pages, boot_pageset); +static DEFINE_PER_CPU(struct per_cpu_zonestat, boot_zonestats); static void __build_all_zonelists(void *data) { int nid; int __maybe_unused cpu; pg_data_t *self = data; - static DEFINE_SPINLOCK(lock); + unsigned long flags; - spin_lock(&lock); + /* + * The zonelist_update_seq must be acquired with irqsave because the + * reader can be invoked from IRQ with GFP_ATOMIC. + */ + write_seqlock_irqsave(&zonelist_update_seq, flags); + /* + * Also disable synchronous printk() to prevent any printk() from + * trying to hold port->lock, for + * tty_insert_flip_string_and_push_buffer() on other CPU might be + * calling kmalloc(GFP_ATOMIC | __GFP_NOWARN) with port->lock held. + */ + printk_deferred_enter(); #ifdef CONFIG_NUMA memset(node_load, 0, sizeof(node_load)); @@ -5520,7 +5787,11 @@ static void __build_all_zonelists(void *data) if (self && !node_online(self->node_id)) { build_zonelists(self); } else { - for_each_online_node(nid) { + /* + * All possible nodes have pgdat preallocated + * in free_area_init + */ + for_each_node(nid) { pg_data_t *pgdat = NODE_DATA(nid); build_zonelists(pgdat); @@ -5540,7 +5811,8 @@ static void __build_all_zonelists(void *data) #endif } - spin_unlock(&lock); + printk_deferred_exit(); + write_sequnlock_irqrestore(&zonelist_update_seq, flags); } static noinline void __init @@ -5564,7 +5836,7 @@ build_all_zonelists_init(void) * (a chicken-egg dilemma). */ for_each_possible_cpu(cpu) - setup_pageset(&per_cpu(boot_pageset, cpu), 0); + per_cpu_pages_init(&per_cpu(boot_pageset, cpu), &per_cpu(boot_zonestats, cpu)); mminit_verify_zonelist(); cpuset_init_current_mems_allowed(); @@ -5578,13 +5850,16 @@ build_all_zonelists_init(void) */ void __ref build_all_zonelists(pg_data_t *pgdat) { + unsigned long vm_total_pages; + if (system_state == SYSTEM_BOOTING) { build_all_zonelists_init(); } else { __build_all_zonelists(pgdat); /* cpuset refresh routine should be here */ } - vm_total_pages = nr_free_pagecache_pages(); + /* Get the number of free pages beyond high watermark in all zones. */ + vm_total_pages = nr_free_zone_pages(gfp_zone(GFP_HIGHUSER_MOVABLE)); /* * Disable grouping by mobility if the number of pages in the * system is too low to allow the mechanism to work. It would be @@ -5597,230 +5872,29 @@ void __ref build_all_zonelists(pg_data_t *pgdat) else page_group_by_mobility_disabled = 0; - pr_info("Built %i zonelists, mobility grouping %s. Total pages: %ld\n", + pr_info("Built %u zonelists, mobility grouping %s. Total pages: %ld\n", nr_online_nodes, - page_group_by_mobility_disabled ? "off" : "on", + str_off_on(page_group_by_mobility_disabled), vm_total_pages); #ifdef CONFIG_NUMA pr_info("Policy zone: %s\n", zone_names[policy_zone]); #endif } -/* If zone is ZONE_MOVABLE but memory is mirrored, it is an overlapped init */ -static bool __meminit -overlap_memmap_init(unsigned long zone, unsigned long *pfn) -{ -#ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP - static struct memblock_region *r; - - if (mirrored_kernelcore && zone == ZONE_MOVABLE) { - if (!r || *pfn >= memblock_region_memory_end_pfn(r)) { - for_each_memblock(memory, r) { - if (*pfn < memblock_region_memory_end_pfn(r)) - break; - } - } - if (*pfn >= memblock_region_memory_base_pfn(r) && - memblock_is_mirror(r)) { - *pfn = memblock_region_memory_end_pfn(r); - return true; - } - } -#endif - return false; -} - -/* - * Initially all pages are reserved - free ones are freed - * up by memblock_free_all() once the early boot process is - * done. Non-atomic initialization, single-pass. - */ -void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone, - unsigned long start_pfn, enum memmap_context context, - struct vmem_altmap *altmap) -{ - unsigned long pfn, end_pfn = start_pfn + size; - struct page *page; - - if (highest_memmap_pfn < end_pfn - 1) - highest_memmap_pfn = end_pfn - 1; - -#ifdef CONFIG_ZONE_DEVICE - /* - * Honor reservation requested by the driver for this ZONE_DEVICE - * memory. We limit the total number of pages to initialize to just - * those that might contain the memory mapping. We will defer the - * ZONE_DEVICE page initialization until after we have released - * the hotplug lock. - */ - if (zone == ZONE_DEVICE) { - if (!altmap) - return; - - if (start_pfn == altmap->base_pfn) - start_pfn += altmap->reserve; - end_pfn = altmap->base_pfn + vmem_altmap_offset(altmap); - } -#endif - - for (pfn = start_pfn; pfn < end_pfn; pfn++) { - /* - * There can be holes in boot-time mem_map[]s handed to this - * function. They do not exist on hotplugged memory. - */ - if (context == MEMMAP_EARLY) { - if (!early_pfn_valid(pfn)) - continue; - if (!early_pfn_in_nid(pfn, nid)) - continue; - if (overlap_memmap_init(zone, &pfn)) - continue; - if (defer_init(nid, pfn, end_pfn)) - break; - } - - page = pfn_to_page(pfn); - __init_single_page(page, pfn, zone, nid); - if (context == MEMMAP_HOTPLUG) - __SetPageReserved(page); - - /* - * Mark the block movable so that blocks are reserved for - * movable at startup. This will force kernel allocations - * to reserve their blocks rather than leaking throughout - * the address space during boot when many long-lived - * kernel allocations are made. - * - * bitmap is created for zone's valid pfn range. but memmap - * can be created for invalid pages (for alignment) - * check here not to call set_pageblock_migratetype() against - * pfn out of zone. - */ - if (!(pfn & (pageblock_nr_pages - 1))) { - set_pageblock_migratetype(page, MIGRATE_MOVABLE); - cond_resched(); - } - } -#ifdef CONFIG_SPARSEMEM - /* - * If the zone does not span the rest of the section then - * we should at least initialize those pages. Otherwise we - * could blow up on a poisoned page in some paths which depend - * on full sections being initialized (e.g. memory hotplug). - */ - while (end_pfn % PAGES_PER_SECTION) { - __init_single_page(pfn_to_page(end_pfn), end_pfn, zone, nid); - end_pfn++; - } -#endif -} - -#ifdef CONFIG_ZONE_DEVICE -void __ref memmap_init_zone_device(struct zone *zone, - unsigned long start_pfn, - unsigned long size, - struct dev_pagemap *pgmap) -{ - unsigned long pfn, end_pfn = start_pfn + size; - struct pglist_data *pgdat = zone->zone_pgdat; - unsigned long zone_idx = zone_idx(zone); - unsigned long start = jiffies; - int nid = pgdat->node_id; - - if (WARN_ON_ONCE(!pgmap || !is_dev_zone(zone))) - return; - - /* - * The call to memmap_init_zone should have already taken care - * of the pages reserved for the memmap, so we can just jump to - * the end of that region and start processing the device pages. - */ - if (pgmap->altmap_valid) { - struct vmem_altmap *altmap = &pgmap->altmap; - - start_pfn = altmap->base_pfn + vmem_altmap_offset(altmap); - size = end_pfn - start_pfn; - } - - for (pfn = start_pfn; pfn < end_pfn; pfn++) { - struct page *page = pfn_to_page(pfn); - - __init_single_page(page, pfn, zone_idx, nid); - - /* - * Mark page reserved as it will need to wait for onlining - * phase for it to be fully associated with a zone. - * - * We can use the non-atomic __set_bit operation for setting - * the flag as we are still initializing the pages. - */ - __SetPageReserved(page); - - /* - * ZONE_DEVICE pages union ->lru with a ->pgmap back - * pointer and hmm_data. It is a bug if a ZONE_DEVICE - * page is ever freed or placed on a driver-private list. - */ - page->pgmap = pgmap; - page->hmm_data = 0; - - /* - * Mark the block movable so that blocks are reserved for - * movable at startup. This will force kernel allocations - * to reserve their blocks rather than leaking throughout - * the address space during boot when many long-lived - * kernel allocations are made. - * - * bitmap is created for zone's valid pfn range. but memmap - * can be created for invalid pages (for alignment) - * check here not to call set_pageblock_migratetype() against - * pfn out of zone. - * - * Please note that MEMMAP_HOTPLUG path doesn't clear memmap - * because this is done early in sparse_add_one_section - */ - if (!(pfn & (pageblock_nr_pages - 1))) { - set_pageblock_migratetype(page, MIGRATE_MOVABLE); - cond_resched(); - } - } - - pr_info("%s initialised, %lu pages in %ums\n", dev_name(pgmap->dev), - size, jiffies_to_msecs(jiffies - start)); -} - -#endif -static void __meminit zone_init_free_lists(struct zone *zone) -{ - unsigned int order, t; - for_each_migratetype_order(order, t) { - INIT_LIST_HEAD(&zone->free_area[order].free_list[t]); - zone->free_area[order].nr_free = 0; - } -} - -void __meminit __weak memmap_init(unsigned long size, int nid, - unsigned long zone, unsigned long start_pfn) -{ - memmap_init_zone(size, nid, zone, start_pfn, MEMMAP_EARLY, NULL); -} - static int zone_batchsize(struct zone *zone) { #ifdef CONFIG_MMU int batch; /* - * The per-cpu-pages pools are set to around 1000th of the - * size of the zone. + * The number of pages to batch allocate is either ~0.025% + * of the zone or 256KB, whichever is smaller. The batch + * size is striking a balance between allocation latency + * and zone lock contention. */ - batch = zone_managed_pages(zone) / 1024; - /* But no more than a meg. */ - if (batch * PAGE_SIZE > 1024 * 1024) - batch = (1024 * 1024) / PAGE_SIZE; - batch /= 4; /* We effectively *= 4 below */ - if (batch < 1) - batch = 1; + batch = min(zone_managed_pages(zone) >> 12, SZ_256K / PAGE_SIZE); + if (batch <= 1) + return 1; /* * Clamp the batch to a 2^n - 1 value. Having a power @@ -5854,1385 +5928,270 @@ static int zone_batchsize(struct zone *zone) #endif } -/* - * pcp->high and pcp->batch values are related and dependent on one another: - * ->batch must never be higher then ->high. - * The following function updates them in a safe manner without read side - * locking. - * - * Any new users of pcp->batch and pcp->high should ensure they can cope with - * those fields changing asynchronously (acording the the above rule). - * - * mutex_is_locked(&pcp_batch_high_lock) required when calling this function - * outside of boot time (or some other assurance that no concurrent updaters - * exist). - */ -static void pageset_update(struct per_cpu_pages *pcp, unsigned long high, - unsigned long batch) -{ - /* start with a fail safe value for batch */ - pcp->batch = 1; - smp_wmb(); - - /* Update high, then batch, in order */ - pcp->high = high; - smp_wmb(); - - pcp->batch = batch; -} - -/* a companion to pageset_set_high() */ -static void pageset_set_batch(struct per_cpu_pageset *p, unsigned long batch) -{ - pageset_update(&p->pcp, 6 * batch, max(1UL, 1 * batch)); -} - -static void pageset_init(struct per_cpu_pageset *p) -{ - struct per_cpu_pages *pcp; - int migratetype; - - memset(p, 0, sizeof(*p)); - - pcp = &p->pcp; - for (migratetype = 0; migratetype < MIGRATE_PCPTYPES; migratetype++) - INIT_LIST_HEAD(&pcp->lists[migratetype]); -} - -static void setup_pageset(struct per_cpu_pageset *p, unsigned long batch) -{ - pageset_init(p); - pageset_set_batch(p, batch); -} - -/* - * pageset_set_high() sets the high water mark for hot per_cpu_pagelist - * to the value high for the pageset p. - */ -static void pageset_set_high(struct per_cpu_pageset *p, - unsigned long high) -{ - unsigned long batch = max(1UL, high / 4); - if ((high / 4) > (PAGE_SHIFT * 8)) - batch = PAGE_SHIFT * 8; - - pageset_update(&p->pcp, high, batch); -} - -static void pageset_set_high_and_batch(struct zone *zone, - struct per_cpu_pageset *pcp) -{ - if (percpu_pagelist_fraction) - pageset_set_high(pcp, - (zone_managed_pages(zone) / - percpu_pagelist_fraction)); - else - pageset_set_batch(pcp, zone_batchsize(zone)); -} - -static void __meminit zone_pageset_init(struct zone *zone, int cpu) -{ - struct per_cpu_pageset *pcp = per_cpu_ptr(zone->pageset, cpu); - - pageset_init(pcp); - pageset_set_high_and_batch(zone, pcp); -} - -void __meminit setup_zone_pageset(struct zone *zone) -{ - int cpu; - zone->pageset = alloc_percpu(struct per_cpu_pageset); - for_each_possible_cpu(cpu) - zone_pageset_init(zone, cpu); -} - -/* - * Allocate per cpu pagesets and initialize them. - * Before this call only boot pagesets were available. - */ -void __init setup_per_cpu_pageset(void) -{ - struct pglist_data *pgdat; - struct zone *zone; - - for_each_populated_zone(zone) - setup_zone_pageset(zone); - - for_each_online_pgdat(pgdat) - pgdat->per_cpu_nodestats = - alloc_percpu(struct per_cpu_nodestat); -} - -static __meminit void zone_pcp_init(struct zone *zone) -{ - /* - * per cpu subsystem is not up at this point. The following code - * relies on the ability of the linker to provide the - * offset of a (static) per cpu variable into the per cpu area. - */ - zone->pageset = &boot_pageset; - - if (populated_zone(zone)) - printk(KERN_DEBUG " %s zone: %lu pages, LIFO batch:%u\n", - zone->name, zone->present_pages, - zone_batchsize(zone)); -} - -void __meminit init_currently_empty_zone(struct zone *zone, - unsigned long zone_start_pfn, - unsigned long size) -{ - struct pglist_data *pgdat = zone->zone_pgdat; - int zone_idx = zone_idx(zone) + 1; - - if (zone_idx > pgdat->nr_zones) - pgdat->nr_zones = zone_idx; - - zone->zone_start_pfn = zone_start_pfn; - - mminit_dprintk(MMINIT_TRACE, "memmap_init", - "Initialising map node %d zone %lu pfns %lu -> %lu\n", - pgdat->node_id, - (unsigned long)zone_idx(zone), - zone_start_pfn, (zone_start_pfn + size)); - - zone_init_free_lists(zone); - zone->initialized = 1; -} - -#ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP -#ifndef CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID - -/* - * Required by SPARSEMEM. Given a PFN, return what node the PFN is on. - */ -int __meminit __early_pfn_to_nid(unsigned long pfn, - struct mminit_pfnnid_cache *state) -{ - unsigned long start_pfn, end_pfn; - int nid; - - if (state->last_start <= pfn && pfn < state->last_end) - return state->last_nid; - - nid = memblock_search_pfn_nid(pfn, &start_pfn, &end_pfn); - if (nid != -1) { - state->last_start = start_pfn; - state->last_end = end_pfn; - state->last_nid = nid; - } - - return nid; -} -#endif /* CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID */ - -/** - * free_bootmem_with_active_regions - Call memblock_free_early_nid for each active range - * @nid: The node to free memory on. If MAX_NUMNODES, all nodes are freed. - * @max_low_pfn: The highest PFN that will be passed to memblock_free_early_nid - * - * If an architecture guarantees that all ranges registered contain no holes - * and may be freed, this this function may be used instead of calling - * memblock_free_early_nid() manually. - */ -void __init free_bootmem_with_active_regions(int nid, unsigned long max_low_pfn) -{ - unsigned long start_pfn, end_pfn; - int i, this_nid; - - for_each_mem_pfn_range(i, nid, &start_pfn, &end_pfn, &this_nid) { - start_pfn = min(start_pfn, max_low_pfn); - end_pfn = min(end_pfn, max_low_pfn); - - if (start_pfn < end_pfn) - memblock_free_early_nid(PFN_PHYS(start_pfn), - (end_pfn - start_pfn) << PAGE_SHIFT, - this_nid); - } -} - -/** - * sparse_memory_present_with_active_regions - Call memory_present for each active range - * @nid: The node to call memory_present for. If MAX_NUMNODES, all nodes will be used. - * - * If an architecture guarantees that all ranges registered contain no holes and may - * be freed, this function may be used instead of calling memory_present() manually. - */ -void __init sparse_memory_present_with_active_regions(int nid) -{ - unsigned long start_pfn, end_pfn; - int i, this_nid; - - for_each_mem_pfn_range(i, nid, &start_pfn, &end_pfn, &this_nid) - memory_present(this_nid, start_pfn, end_pfn); -} - -/** - * get_pfn_range_for_nid - Return the start and end page frames for a node - * @nid: The nid to return the range for. If MAX_NUMNODES, the min and max PFN are returned. - * @start_pfn: Passed by reference. On return, it will have the node start_pfn. - * @end_pfn: Passed by reference. On return, it will have the node end_pfn. - * - * It returns the start and end page frame of a node based on information - * provided by memblock_set_node(). If called for a node - * with no available memory, a warning is printed and the start and end - * PFNs will be 0. - */ -void __init get_pfn_range_for_nid(unsigned int nid, - unsigned long *start_pfn, unsigned long *end_pfn) -{ - unsigned long this_start_pfn, this_end_pfn; - int i; - - *start_pfn = -1UL; - *end_pfn = 0; - - for_each_mem_pfn_range(i, nid, &this_start_pfn, &this_end_pfn, NULL) { - *start_pfn = min(*start_pfn, this_start_pfn); - *end_pfn = max(*end_pfn, this_end_pfn); - } - - if (*start_pfn == -1UL) - *start_pfn = 0; -} - -/* - * This finds a zone that can be used for ZONE_MOVABLE pages. The - * assumption is made that zones within a node are ordered in monotonic - * increasing memory addresses so that the "highest" populated zone is used - */ -static void __init find_usable_zone_for_movable(void) -{ - int zone_index; - for (zone_index = MAX_NR_ZONES - 1; zone_index >= 0; zone_index--) { - if (zone_index == ZONE_MOVABLE) - continue; - - if (arch_zone_highest_possible_pfn[zone_index] > - arch_zone_lowest_possible_pfn[zone_index]) - break; - } - - VM_BUG_ON(zone_index == -1); - movable_zone = zone_index; -} - -/* - * The zone ranges provided by the architecture do not include ZONE_MOVABLE - * because it is sized independent of architecture. Unlike the other zones, - * the starting point for ZONE_MOVABLE is not fixed. It may be different - * in each node depending on the size of each node and how evenly kernelcore - * is distributed. This helper function adjusts the zone ranges - * provided by the architecture for a given node by using the end of the - * highest usable zone for ZONE_MOVABLE. This preserves the assumption that - * zones within a node are in order of monotonic increases memory addresses - */ -static void __init adjust_zone_range_for_zone_movable(int nid, - unsigned long zone_type, - unsigned long node_start_pfn, - unsigned long node_end_pfn, - unsigned long *zone_start_pfn, - unsigned long *zone_end_pfn) -{ - /* Only adjust if ZONE_MOVABLE is on this node */ - if (zone_movable_pfn[nid]) { - /* Size ZONE_MOVABLE */ - if (zone_type == ZONE_MOVABLE) { - *zone_start_pfn = zone_movable_pfn[nid]; - *zone_end_pfn = min(node_end_pfn, - arch_zone_highest_possible_pfn[movable_zone]); - - /* Adjust for ZONE_MOVABLE starting within this range */ - } else if (!mirrored_kernelcore && - *zone_start_pfn < zone_movable_pfn[nid] && - *zone_end_pfn > zone_movable_pfn[nid]) { - *zone_end_pfn = zone_movable_pfn[nid]; - - /* Check if this whole range is within ZONE_MOVABLE */ - } else if (*zone_start_pfn >= zone_movable_pfn[nid]) - *zone_start_pfn = *zone_end_pfn; - } -} - -/* - * Return the number of pages a zone spans in a node, including holes - * present_pages = zone_spanned_pages_in_node() - zone_absent_pages_in_node() - */ -static unsigned long __init zone_spanned_pages_in_node(int nid, - unsigned long zone_type, - unsigned long node_start_pfn, - unsigned long node_end_pfn, - unsigned long *zone_start_pfn, - unsigned long *zone_end_pfn, - unsigned long *ignored) -{ - /* When hotadd a new node from cpu_up(), the node should be empty */ - if (!node_start_pfn && !node_end_pfn) - return 0; - - /* Get the start and end of the zone */ - *zone_start_pfn = arch_zone_lowest_possible_pfn[zone_type]; - *zone_end_pfn = arch_zone_highest_possible_pfn[zone_type]; - adjust_zone_range_for_zone_movable(nid, zone_type, - node_start_pfn, node_end_pfn, - zone_start_pfn, zone_end_pfn); - - /* Check that this node has pages within the zone's required range */ - if (*zone_end_pfn < node_start_pfn || *zone_start_pfn > node_end_pfn) - return 0; - - /* Move the zone boundaries inside the node if necessary */ - *zone_end_pfn = min(*zone_end_pfn, node_end_pfn); - *zone_start_pfn = max(*zone_start_pfn, node_start_pfn); - - /* Return the spanned pages */ - return *zone_end_pfn - *zone_start_pfn; -} - -/* - * Return the number of holes in a range on a node. If nid is MAX_NUMNODES, - * then all holes in the requested range will be accounted for. - */ -unsigned long __init __absent_pages_in_range(int nid, - unsigned long range_start_pfn, - unsigned long range_end_pfn) -{ - unsigned long nr_absent = range_end_pfn - range_start_pfn; - unsigned long start_pfn, end_pfn; - int i; - - for_each_mem_pfn_range(i, nid, &start_pfn, &end_pfn, NULL) { - start_pfn = clamp(start_pfn, range_start_pfn, range_end_pfn); - end_pfn = clamp(end_pfn, range_start_pfn, range_end_pfn); - nr_absent -= end_pfn - start_pfn; - } - return nr_absent; -} - -/** - * absent_pages_in_range - Return number of page frames in holes within a range - * @start_pfn: The start PFN to start searching for holes - * @end_pfn: The end PFN to stop searching for holes - * - * It returns the number of pages frames in memory holes within a range. - */ -unsigned long __init absent_pages_in_range(unsigned long start_pfn, - unsigned long end_pfn) -{ - return __absent_pages_in_range(MAX_NUMNODES, start_pfn, end_pfn); -} - -/* Return the number of page frames in holes in a zone on a node */ -static unsigned long __init zone_absent_pages_in_node(int nid, - unsigned long zone_type, - unsigned long node_start_pfn, - unsigned long node_end_pfn, - unsigned long *ignored) -{ - unsigned long zone_low = arch_zone_lowest_possible_pfn[zone_type]; - unsigned long zone_high = arch_zone_highest_possible_pfn[zone_type]; - unsigned long zone_start_pfn, zone_end_pfn; - unsigned long nr_absent; - - /* When hotadd a new node from cpu_up(), the node should be empty */ - if (!node_start_pfn && !node_end_pfn) - return 0; - - zone_start_pfn = clamp(node_start_pfn, zone_low, zone_high); - zone_end_pfn = clamp(node_end_pfn, zone_low, zone_high); - - adjust_zone_range_for_zone_movable(nid, zone_type, - node_start_pfn, node_end_pfn, - &zone_start_pfn, &zone_end_pfn); - nr_absent = __absent_pages_in_range(nid, zone_start_pfn, zone_end_pfn); - - /* - * ZONE_MOVABLE handling. - * Treat pages to be ZONE_MOVABLE in ZONE_NORMAL as absent pages - * and vice versa. - */ - if (mirrored_kernelcore && zone_movable_pfn[nid]) { - unsigned long start_pfn, end_pfn; - struct memblock_region *r; - - for_each_memblock(memory, r) { - start_pfn = clamp(memblock_region_memory_base_pfn(r), - zone_start_pfn, zone_end_pfn); - end_pfn = clamp(memblock_region_memory_end_pfn(r), - zone_start_pfn, zone_end_pfn); - - if (zone_type == ZONE_MOVABLE && - memblock_is_mirror(r)) - nr_absent += end_pfn - start_pfn; - - if (zone_type == ZONE_NORMAL && - !memblock_is_mirror(r)) - nr_absent += end_pfn - start_pfn; - } - } - - return nr_absent; -} - -#else /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */ -static inline unsigned long __init zone_spanned_pages_in_node(int nid, - unsigned long zone_type, - unsigned long node_start_pfn, - unsigned long node_end_pfn, - unsigned long *zone_start_pfn, - unsigned long *zone_end_pfn, - unsigned long *zones_size) +static int percpu_pagelist_high_fraction; +static int zone_highsize(struct zone *zone, int batch, int cpu_online, + int high_fraction) { - unsigned int zone; - - *zone_start_pfn = node_start_pfn; - for (zone = 0; zone < zone_type; zone++) - *zone_start_pfn += zones_size[zone]; - - *zone_end_pfn = *zone_start_pfn + zones_size[zone_type]; - - return zones_size[zone_type]; -} - -static inline unsigned long __init zone_absent_pages_in_node(int nid, - unsigned long zone_type, - unsigned long node_start_pfn, - unsigned long node_end_pfn, - unsigned long *zholes_size) -{ - if (!zholes_size) - return 0; - - return zholes_size[zone_type]; -} - -#endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */ - -static void __init calculate_node_totalpages(struct pglist_data *pgdat, - unsigned long node_start_pfn, - unsigned long node_end_pfn, - unsigned long *zones_size, - unsigned long *zholes_size) -{ - unsigned long realtotalpages = 0, totalpages = 0; - enum zone_type i; - - for (i = 0; i < MAX_NR_ZONES; i++) { - struct zone *zone = pgdat->node_zones + i; - unsigned long zone_start_pfn, zone_end_pfn; - unsigned long size, real_size; - - size = zone_spanned_pages_in_node(pgdat->node_id, i, - node_start_pfn, - node_end_pfn, - &zone_start_pfn, - &zone_end_pfn, - zones_size); - real_size = size - zone_absent_pages_in_node(pgdat->node_id, i, - node_start_pfn, node_end_pfn, - zholes_size); - if (size) - zone->zone_start_pfn = zone_start_pfn; - else - zone->zone_start_pfn = 0; - zone->spanned_pages = size; - zone->present_pages = real_size; +#ifdef CONFIG_MMU + int high; + int nr_split_cpus; + unsigned long total_pages; - totalpages += size; - realtotalpages += real_size; + if (!high_fraction) { + /* + * By default, the high value of the pcp is based on the zone + * low watermark so that if they are full then background + * reclaim will not be started prematurely. + */ + total_pages = low_wmark_pages(zone); + } else { + /* + * If percpu_pagelist_high_fraction is configured, the high + * value is based on a fraction of the managed pages in the + * zone. + */ + total_pages = zone_managed_pages(zone) / high_fraction; } - pgdat->node_spanned_pages = totalpages; - pgdat->node_present_pages = realtotalpages; - printk(KERN_DEBUG "On node %d totalpages: %lu\n", pgdat->node_id, - realtotalpages); -} - -#ifndef CONFIG_SPARSEMEM -/* - * Calculate the size of the zone->blockflags rounded to an unsigned long - * Start by making sure zonesize is a multiple of pageblock_order by rounding - * up. Then use 1 NR_PAGEBLOCK_BITS worth of bits per pageblock, finally - * round what is now in bits to nearest long in bits, then return it in - * bytes. - */ -static unsigned long __init usemap_size(unsigned long zone_start_pfn, unsigned long zonesize) -{ - unsigned long usemapsize; - - zonesize += zone_start_pfn & (pageblock_nr_pages-1); - usemapsize = roundup(zonesize, pageblock_nr_pages); - usemapsize = usemapsize >> pageblock_order; - usemapsize *= NR_PAGEBLOCK_BITS; - usemapsize = roundup(usemapsize, 8 * sizeof(unsigned long)); - - return usemapsize / 8; -} - -static void __ref setup_usemap(struct pglist_data *pgdat, - struct zone *zone, - unsigned long zone_start_pfn, - unsigned long zonesize) -{ - unsigned long usemapsize = usemap_size(zone_start_pfn, zonesize); - zone->pageblock_flags = NULL; - if (usemapsize) - zone->pageblock_flags = - memblock_alloc_node_nopanic(usemapsize, - pgdat->node_id); -} -#else -static inline void setup_usemap(struct pglist_data *pgdat, struct zone *zone, - unsigned long zone_start_pfn, unsigned long zonesize) {} -#endif /* CONFIG_SPARSEMEM */ - -#ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE - -/* Initialise the number of pages represented by NR_PAGEBLOCK_BITS */ -void __init set_pageblock_order(void) -{ - unsigned int order; - - /* Check that pageblock_nr_pages has not already been setup */ - if (pageblock_order) - return; - - if (HPAGE_SHIFT > PAGE_SHIFT) - order = HUGETLB_PAGE_ORDER; - else - order = MAX_ORDER - 1; - /* - * Assume the largest contiguous order of interest is a huge page. - * This value may be variable depending on boot parameters on IA64 and - * powerpc. + * Split the high value across all online CPUs local to the zone. Note + * that early in boot that CPUs may not be online yet and that during + * CPU hotplug that the cpumask is not yet updated when a CPU is being + * onlined. For memory nodes that have no CPUs, split the high value + * across all online CPUs to mitigate the risk that reclaim is triggered + * prematurely due to pages stored on pcp lists. */ - pageblock_order = order; -} -#else /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */ - -/* - * When CONFIG_HUGETLB_PAGE_SIZE_VARIABLE is not set, set_pageblock_order() - * is unused as pageblock_order is set at compile-time. See - * include/linux/pageblock-flags.h for the values of pageblock_order based on - * the kernel config - */ -void __init set_pageblock_order(void) -{ -} - -#endif /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */ - -static unsigned long __init calc_memmap_size(unsigned long spanned_pages, - unsigned long present_pages) -{ - unsigned long pages = spanned_pages; + nr_split_cpus = cpumask_weight(cpumask_of_node(zone_to_nid(zone))) + cpu_online; + if (!nr_split_cpus) + nr_split_cpus = num_online_cpus(); + high = total_pages / nr_split_cpus; /* - * Provide a more accurate estimation if there are holes within - * the zone and SPARSEMEM is in use. If there are holes within the - * zone, each populated memory region may cost us one or two extra - * memmap pages due to alignment because memmap pages for each - * populated regions may not be naturally aligned on page boundary. - * So the (present_pages >> 4) heuristic is a tradeoff for that. + * Ensure high is at least batch*4. The multiple is based on the + * historical relationship between high and batch. */ - if (spanned_pages > present_pages + (present_pages >> 4) && - IS_ENABLED(CONFIG_SPARSEMEM)) - pages = present_pages; - - return PAGE_ALIGN(pages * sizeof(struct page)) >> PAGE_SHIFT; -} + high = max(high, batch << 2); -#ifdef CONFIG_TRANSPARENT_HUGEPAGE -static void pgdat_init_split_queue(struct pglist_data *pgdat) -{ - spin_lock_init(&pgdat->split_queue_lock); - INIT_LIST_HEAD(&pgdat->split_queue); - pgdat->split_queue_len = 0; -} + return high; #else -static void pgdat_init_split_queue(struct pglist_data *pgdat) {} -#endif - -#ifdef CONFIG_COMPACTION -static void pgdat_init_kcompactd(struct pglist_data *pgdat) -{ - init_waitqueue_head(&pgdat->kcompactd_wait); -} -#else -static void pgdat_init_kcompactd(struct pglist_data *pgdat) {} + return 0; #endif - -static void __meminit pgdat_init_internals(struct pglist_data *pgdat) -{ - pgdat_resize_init(pgdat); - - pgdat_init_split_queue(pgdat); - pgdat_init_kcompactd(pgdat); - - init_waitqueue_head(&pgdat->kswapd_wait); - init_waitqueue_head(&pgdat->pfmemalloc_wait); - - pgdat_page_ext_init(pgdat); - spin_lock_init(&pgdat->lru_lock); - lruvec_init(node_lruvec(pgdat)); -} - -static void __meminit zone_init_internals(struct zone *zone, enum zone_type idx, int nid, - unsigned long remaining_pages) -{ - atomic_long_set(&zone->managed_pages, remaining_pages); - zone_set_nid(zone, nid); - zone->name = zone_names[idx]; - zone->zone_pgdat = NODE_DATA(nid); - spin_lock_init(&zone->lock); - zone_seqlock_init(zone); - zone_pcp_init(zone); } /* - * Set up the zone data structures - * - init pgdat internals - * - init all zones belonging to this node + * pcp->high and pcp->batch values are related and generally batch is lower + * than high. They are also related to pcp->count such that count is lower + * than high, and as soon as it reaches high, the pcplist is flushed. * - * NOTE: this function is only called during memory hotplug - */ -#ifdef CONFIG_MEMORY_HOTPLUG -void __ref free_area_init_core_hotplug(int nid) -{ - enum zone_type z; - pg_data_t *pgdat = NODE_DATA(nid); - - pgdat_init_internals(pgdat); - for (z = 0; z < MAX_NR_ZONES; z++) - zone_init_internals(&pgdat->node_zones[z], z, nid, 0); -} -#endif - -/* - * Set up the zone data structures: - * - mark all pages reserved - * - mark all memory queues empty - * - clear the memory bitmaps + * However, guaranteeing these relations at all times would require e.g. write + * barriers here but also careful usage of read barriers at the read side, and + * thus be prone to error and bad for performance. Thus the update only prevents + * store tearing. Any new users of pcp->batch, pcp->high_min and pcp->high_max + * should ensure they can cope with those fields changing asynchronously, and + * fully trust only the pcp->count field on the local CPU with interrupts + * disabled. * - * NOTE: pgdat should get zeroed by caller. - * NOTE: this function is only called during early init. + * mutex_is_locked(&pcp_batch_high_lock) required when calling this function + * outside of boot time (or some other assurance that no concurrent updaters + * exist). */ -static void __init free_area_init_core(struct pglist_data *pgdat) +static void pageset_update(struct per_cpu_pages *pcp, unsigned long high_min, + unsigned long high_max, unsigned long batch) { - enum zone_type j; - int nid = pgdat->node_id; - - pgdat_init_internals(pgdat); - pgdat->per_cpu_nodestats = &boot_nodestats; - - for (j = 0; j < MAX_NR_ZONES; j++) { - struct zone *zone = pgdat->node_zones + j; - unsigned long size, freesize, memmap_pages; - unsigned long zone_start_pfn = zone->zone_start_pfn; - - size = zone->spanned_pages; - freesize = zone->present_pages; - - /* - * Adjust freesize so that it accounts for how much memory - * is used by this zone for memmap. This affects the watermark - * and per-cpu initialisations - */ - memmap_pages = calc_memmap_size(size, freesize); - if (!is_highmem_idx(j)) { - if (freesize >= memmap_pages) { - freesize -= memmap_pages; - if (memmap_pages) - printk(KERN_DEBUG - " %s zone: %lu pages used for memmap\n", - zone_names[j], memmap_pages); - } else - pr_warn(" %s zone: %lu pages exceeds freesize %lu\n", - zone_names[j], memmap_pages, freesize); - } - - /* Account for reserved pages */ - if (j == 0 && freesize > dma_reserve) { - freesize -= dma_reserve; - printk(KERN_DEBUG " %s zone: %lu pages reserved\n", - zone_names[0], dma_reserve); - } - - if (!is_highmem_idx(j)) - nr_kernel_pages += freesize; - /* Charge for highmem memmap if there are enough kernel pages */ - else if (nr_kernel_pages > memmap_pages * 2) - nr_kernel_pages -= memmap_pages; - nr_all_pages += freesize; - - /* - * Set an approximate value for lowmem here, it will be adjusted - * when the bootmem allocator frees pages into the buddy system. - * And all highmem pages will be managed by the buddy system. - */ - zone_init_internals(zone, j, nid, freesize); - - if (!size) - continue; - - set_pageblock_order(); - setup_usemap(pgdat, zone, zone_start_pfn, size); - init_currently_empty_zone(zone, zone_start_pfn, size); - memmap_init(size, nid, j, zone_start_pfn); - } + WRITE_ONCE(pcp->batch, batch); + WRITE_ONCE(pcp->high_min, high_min); + WRITE_ONCE(pcp->high_max, high_max); } -#ifdef CONFIG_FLAT_NODE_MEM_MAP -static void __ref alloc_node_mem_map(struct pglist_data *pgdat) +static void per_cpu_pages_init(struct per_cpu_pages *pcp, struct per_cpu_zonestat *pzstats) { - unsigned long __maybe_unused start = 0; - unsigned long __maybe_unused offset = 0; + int pindex; - /* Skip empty nodes */ - if (!pgdat->node_spanned_pages) - return; + memset(pcp, 0, sizeof(*pcp)); + memset(pzstats, 0, sizeof(*pzstats)); - start = pgdat->node_start_pfn & ~(MAX_ORDER_NR_PAGES - 1); - offset = pgdat->node_start_pfn - start; - /* ia64 gets its own node_mem_map, before this, without bootmem */ - if (!pgdat->node_mem_map) { - unsigned long size, end; - struct page *map; + spin_lock_init(&pcp->lock); + for (pindex = 0; pindex < NR_PCP_LISTS; pindex++) + INIT_LIST_HEAD(&pcp->lists[pindex]); - /* - * The zone's endpoints aren't required to be MAX_ORDER - * aligned but the node_mem_map endpoints must be in order - * for the buddy allocator to function correctly. - */ - end = pgdat_end_pfn(pgdat); - end = ALIGN(end, MAX_ORDER_NR_PAGES); - size = (end - start) * sizeof(struct page); - map = memblock_alloc_node_nopanic(size, pgdat->node_id); - pgdat->node_mem_map = map + offset; - } - pr_debug("%s: node %d, pgdat %08lx, node_mem_map %08lx\n", - __func__, pgdat->node_id, (unsigned long)pgdat, - (unsigned long)pgdat->node_mem_map); -#ifndef CONFIG_NEED_MULTIPLE_NODES /* - * With no DISCONTIG, the global mem_map is just set as node 0's + * Set batch and high values safe for a boot pageset. A true percpu + * pageset's initialization will update them subsequently. Here we don't + * need to be as careful as pageset_update() as nobody can access the + * pageset yet. */ - if (pgdat == NODE_DATA(0)) { - mem_map = NODE_DATA(0)->node_mem_map; -#if defined(CONFIG_HAVE_MEMBLOCK_NODE_MAP) || defined(CONFIG_FLATMEM) - if (page_to_pfn(mem_map) != pgdat->node_start_pfn) - mem_map -= offset; -#endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */ - } -#endif + pcp->high_min = BOOT_PAGESET_HIGH; + pcp->high_max = BOOT_PAGESET_HIGH; + pcp->batch = BOOT_PAGESET_BATCH; } -#else -static void __ref alloc_node_mem_map(struct pglist_data *pgdat) { } -#endif /* CONFIG_FLAT_NODE_MEM_MAP */ -#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT -static inline void pgdat_set_deferred_range(pg_data_t *pgdat) -{ - pgdat->first_deferred_pfn = ULONG_MAX; -} -#else -static inline void pgdat_set_deferred_range(pg_data_t *pgdat) {} -#endif - -void __init free_area_init_node(int nid, unsigned long *zones_size, - unsigned long node_start_pfn, - unsigned long *zholes_size) -{ - pg_data_t *pgdat = NODE_DATA(nid); - unsigned long start_pfn = 0; - unsigned long end_pfn = 0; - - /* pg_data_t should be reset to zero when it's allocated */ - WARN_ON(pgdat->nr_zones || pgdat->kswapd_classzone_idx); - - pgdat->node_id = nid; - pgdat->node_start_pfn = node_start_pfn; - pgdat->per_cpu_nodestats = NULL; -#ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP - get_pfn_range_for_nid(nid, &start_pfn, &end_pfn); - pr_info("Initmem setup node %d [mem %#018Lx-%#018Lx]\n", nid, - (u64)start_pfn << PAGE_SHIFT, - end_pfn ? ((u64)end_pfn << PAGE_SHIFT) - 1 : 0); -#else - start_pfn = node_start_pfn; -#endif - calculate_node_totalpages(pgdat, start_pfn, end_pfn, - zones_size, zholes_size); - - alloc_node_mem_map(pgdat); - pgdat_set_deferred_range(pgdat); - - free_area_init_core(pgdat); -} - -#if !defined(CONFIG_FLAT_NODE_MEM_MAP) -/* - * Zero all valid struct pages in range [spfn, epfn), return number of struct - * pages zeroed - */ -static u64 zero_pfn_range(unsigned long spfn, unsigned long epfn) +static void __zone_set_pageset_high_and_batch(struct zone *zone, unsigned long high_min, + unsigned long high_max, unsigned long batch) { - unsigned long pfn; - u64 pgcnt = 0; + struct per_cpu_pages *pcp; + int cpu; - for (pfn = spfn; pfn < epfn; pfn++) { - if (!pfn_valid(ALIGN_DOWN(pfn, pageblock_nr_pages))) { - pfn = ALIGN_DOWN(pfn, pageblock_nr_pages) - + pageblock_nr_pages - 1; - continue; - } - mm_zero_struct_page(pfn_to_page(pfn)); - pgcnt++; + for_each_possible_cpu(cpu) { + pcp = per_cpu_ptr(zone->per_cpu_pageset, cpu); + pageset_update(pcp, high_min, high_max, batch); } - - return pgcnt; } /* - * Only struct pages that are backed by physical memory are zeroed and - * initialized by going through __init_single_page(). But, there are some - * struct pages which are reserved in memblock allocator and their fields - * may be accessed (for example page_to_pfn() on some configuration accesses - * flags). We must explicitly zero those struct pages. - * - * This function also addresses a similar issue where struct pages are left - * uninitialized because the physical address range is not covered by - * memblock.memory or memblock.reserved. That could happen when memblock - * layout is manually configured via memmap=. + * Calculate and set new high and batch values for all per-cpu pagesets of a + * zone based on the zone's size. */ -void __init zero_resv_unavail(void) +static void zone_set_pageset_high_and_batch(struct zone *zone, int cpu_online) { - phys_addr_t start, end; - u64 i, pgcnt; - phys_addr_t next = 0; + int new_high_min, new_high_max, new_batch; - /* - * Loop through unavailable ranges not covered by memblock.memory. - */ - pgcnt = 0; - for_each_mem_range(i, &memblock.memory, NULL, - NUMA_NO_NODE, MEMBLOCK_NONE, &start, &end, NULL) { - if (next < start) - pgcnt += zero_pfn_range(PFN_DOWN(next), PFN_UP(start)); - next = end; + new_batch = zone_batchsize(zone); + if (percpu_pagelist_high_fraction) { + new_high_min = zone_highsize(zone, new_batch, cpu_online, + percpu_pagelist_high_fraction); + /* + * PCP high is tuned manually, disable auto-tuning via + * setting high_min and high_max to the manual value. + */ + new_high_max = new_high_min; + } else { + new_high_min = zone_highsize(zone, new_batch, cpu_online, 0); + new_high_max = zone_highsize(zone, new_batch, cpu_online, + MIN_PERCPU_PAGELIST_HIGH_FRACTION); } - pgcnt += zero_pfn_range(PFN_DOWN(next), max_pfn); - - /* - * Struct pages that do not have backing memory. This could be because - * firmware is using some of this memory, or for some other reasons. - */ - if (pgcnt) - pr_info("Zeroed struct page in unavailable ranges: %lld pages", pgcnt); -} -#endif /* !CONFIG_FLAT_NODE_MEM_MAP */ -#ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP + if (zone->pageset_high_min == new_high_min && + zone->pageset_high_max == new_high_max && + zone->pageset_batch == new_batch) + return; -#if MAX_NUMNODES > 1 -/* - * Figure out the number of possible node ids. - */ -void __init setup_nr_node_ids(void) -{ - unsigned int highest; + zone->pageset_high_min = new_high_min; + zone->pageset_high_max = new_high_max; + zone->pageset_batch = new_batch; - highest = find_last_bit(node_possible_map.bits, MAX_NUMNODES); - nr_node_ids = highest + 1; + __zone_set_pageset_high_and_batch(zone, new_high_min, new_high_max, + new_batch); } -#endif -/** - * node_map_pfn_alignment - determine the maximum internode alignment - * - * This function should be called after node map is populated and sorted. - * It calculates the maximum power of two alignment which can distinguish - * all the nodes. - * - * For example, if all nodes are 1GiB and aligned to 1GiB, the return value - * would indicate 1GiB alignment with (1 << (30 - PAGE_SHIFT)). If the - * nodes are shifted by 256MiB, 256MiB. Note that if only the last node is - * shifted, 1GiB is enough and this function will indicate so. - * - * This is used to test whether pfn -> nid mapping of the chosen memory - * model has fine enough granularity to avoid incorrect mapping for the - * populated node map. - * - * Returns the determined alignment in pfn's. 0 if there is no alignment - * requirement (single node). - */ -unsigned long __init node_map_pfn_alignment(void) +void __meminit setup_zone_pageset(struct zone *zone) { - unsigned long accl_mask = 0, last_end = 0; - unsigned long start, end, mask; - int last_nid = -1; - int i, nid; - - for_each_mem_pfn_range(i, MAX_NUMNODES, &start, &end, &nid) { - if (!start || last_nid < 0 || last_nid == nid) { - last_nid = nid; - last_end = end; - continue; - } - - /* - * Start with a mask granular enough to pin-point to the - * start pfn and tick off bits one-by-one until it becomes - * too coarse to separate the current node from the last. - */ - mask = ~((1 << __ffs(start)) - 1); - while (mask && last_end <= (start & (mask << 1))) - mask <<= 1; - - /* accumulate all internode masks */ - accl_mask |= mask; - } - - /* convert mask to number of pages */ - return ~accl_mask + 1; -} + int cpu; -/* Find the lowest pfn for a node */ -static unsigned long __init find_min_pfn_for_node(int nid) -{ - unsigned long min_pfn = ULONG_MAX; - unsigned long start_pfn; - int i; + /* Size may be 0 on !SMP && !NUMA */ + if (sizeof(struct per_cpu_zonestat) > 0) + zone->per_cpu_zonestats = alloc_percpu(struct per_cpu_zonestat); - for_each_mem_pfn_range(i, nid, &start_pfn, NULL, NULL) - min_pfn = min(min_pfn, start_pfn); + zone->per_cpu_pageset = alloc_percpu(struct per_cpu_pages); + for_each_possible_cpu(cpu) { + struct per_cpu_pages *pcp; + struct per_cpu_zonestat *pzstats; - if (min_pfn == ULONG_MAX) { - pr_warn("Could not find start_pfn for node %d\n", nid); - return 0; + pcp = per_cpu_ptr(zone->per_cpu_pageset, cpu); + pzstats = per_cpu_ptr(zone->per_cpu_zonestats, cpu); + per_cpu_pages_init(pcp, pzstats); } - return min_pfn; -} - -/** - * find_min_pfn_with_active_regions - Find the minimum PFN registered - * - * It returns the minimum PFN based on information provided via - * memblock_set_node(). - */ -unsigned long __init find_min_pfn_with_active_regions(void) -{ - return find_min_pfn_for_node(MAX_NUMNODES); + zone_set_pageset_high_and_batch(zone, 0); } /* - * early_calculate_totalpages() - * Sum pages in active regions for movable zone. - * Populate N_MEMORY for calculating usable_nodes. + * The zone indicated has a new number of managed_pages; batch sizes and percpu + * page high values need to be recalculated. */ -static unsigned long __init early_calculate_totalpages(void) +static void zone_pcp_update(struct zone *zone, int cpu_online) { - unsigned long totalpages = 0; - unsigned long start_pfn, end_pfn; - int i, nid; - - for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, &nid) { - unsigned long pages = end_pfn - start_pfn; - - totalpages += pages; - if (pages) - node_set_state(nid, N_MEMORY); - } - return totalpages; + mutex_lock(&pcp_batch_high_lock); + zone_set_pageset_high_and_batch(zone, cpu_online); + mutex_unlock(&pcp_batch_high_lock); } -/* - * Find the PFN the Movable zone begins in each node. Kernel memory - * is spread evenly between nodes as long as the nodes have enough - * memory. When they don't, some nodes will have more kernelcore than - * others - */ -static void __init find_zone_movable_pfns_for_nodes(void) +static void zone_pcp_update_cacheinfo(struct zone *zone, unsigned int cpu) { - int i, nid; - unsigned long usable_startpfn; - unsigned long kernelcore_node, kernelcore_remaining; - /* save the state before borrow the nodemask */ - nodemask_t saved_node_state = node_states[N_MEMORY]; - unsigned long totalpages = early_calculate_totalpages(); - int usable_nodes = nodes_weight(node_states[N_MEMORY]); - struct memblock_region *r; - - /* Need to find movable_zone earlier when movable_node is specified. */ - find_usable_zone_for_movable(); - - /* - * If movable_node is specified, ignore kernelcore and movablecore - * options. - */ - if (movable_node_is_enabled()) { - for_each_memblock(memory, r) { - if (!memblock_is_hotpluggable(r)) - continue; - - nid = r->nid; - - usable_startpfn = PFN_DOWN(r->base); - zone_movable_pfn[nid] = zone_movable_pfn[nid] ? - min(usable_startpfn, zone_movable_pfn[nid]) : - usable_startpfn; - } - - goto out2; - } - - /* - * If kernelcore=mirror is specified, ignore movablecore option - */ - if (mirrored_kernelcore) { - bool mem_below_4gb_not_mirrored = false; - - for_each_memblock(memory, r) { - if (memblock_is_mirror(r)) - continue; - - nid = r->nid; - - usable_startpfn = memblock_region_memory_base_pfn(r); - - if (usable_startpfn < 0x100000) { - mem_below_4gb_not_mirrored = true; - continue; - } - - zone_movable_pfn[nid] = zone_movable_pfn[nid] ? - min(usable_startpfn, zone_movable_pfn[nid]) : - usable_startpfn; - } - - if (mem_below_4gb_not_mirrored) - pr_warn("This configuration results in unmirrored kernel memory."); - - goto out2; - } - - /* - * If kernelcore=nn% or movablecore=nn% was specified, calculate the - * amount of necessary memory. - */ - if (required_kernelcore_percent) - required_kernelcore = (totalpages * 100 * required_kernelcore_percent) / - 10000UL; - if (required_movablecore_percent) - required_movablecore = (totalpages * 100 * required_movablecore_percent) / - 10000UL; - - /* - * If movablecore= was specified, calculate what size of - * kernelcore that corresponds so that memory usable for - * any allocation type is evenly spread. If both kernelcore - * and movablecore are specified, then the value of kernelcore - * will be used for required_kernelcore if it's greater than - * what movablecore would have allowed. - */ - if (required_movablecore) { - unsigned long corepages; - - /* - * Round-up so that ZONE_MOVABLE is at least as large as what - * was requested by the user - */ - required_movablecore = - roundup(required_movablecore, MAX_ORDER_NR_PAGES); - required_movablecore = min(totalpages, required_movablecore); - corepages = totalpages - required_movablecore; - - required_kernelcore = max(required_kernelcore, corepages); - } - - /* - * If kernelcore was not specified or kernelcore size is larger - * than totalpages, there is no ZONE_MOVABLE. - */ - if (!required_kernelcore || required_kernelcore >= totalpages) - goto out; - - /* usable_startpfn is the lowest possible pfn ZONE_MOVABLE can be at */ - usable_startpfn = arch_zone_lowest_possible_pfn[movable_zone]; - -restart: - /* Spread kernelcore memory as evenly as possible throughout nodes */ - kernelcore_node = required_kernelcore / usable_nodes; - for_each_node_state(nid, N_MEMORY) { - unsigned long start_pfn, end_pfn; - - /* - * Recalculate kernelcore_node if the division per node - * now exceeds what is necessary to satisfy the requested - * amount of memory for the kernel - */ - if (required_kernelcore < kernelcore_node) - kernelcore_node = required_kernelcore / usable_nodes; - - /* - * As the map is walked, we track how much memory is usable - * by the kernel using kernelcore_remaining. When it is - * 0, the rest of the node is usable by ZONE_MOVABLE - */ - kernelcore_remaining = kernelcore_node; - - /* Go through each range of PFNs within this node */ - for_each_mem_pfn_range(i, nid, &start_pfn, &end_pfn, NULL) { - unsigned long size_pages; - - start_pfn = max(start_pfn, zone_movable_pfn[nid]); - if (start_pfn >= end_pfn) - continue; - - /* Account for what is only usable for kernelcore */ - if (start_pfn < usable_startpfn) { - unsigned long kernel_pages; - kernel_pages = min(end_pfn, usable_startpfn) - - start_pfn; - - kernelcore_remaining -= min(kernel_pages, - kernelcore_remaining); - required_kernelcore -= min(kernel_pages, - required_kernelcore); - - /* Continue if range is now fully accounted */ - if (end_pfn <= usable_startpfn) { - - /* - * Push zone_movable_pfn to the end so - * that if we have to rebalance - * kernelcore across nodes, we will - * not double account here - */ - zone_movable_pfn[nid] = end_pfn; - continue; - } - start_pfn = usable_startpfn; - } - - /* - * The usable PFN range for ZONE_MOVABLE is from - * start_pfn->end_pfn. Calculate size_pages as the - * number of pages used as kernelcore - */ - size_pages = end_pfn - start_pfn; - if (size_pages > kernelcore_remaining) - size_pages = kernelcore_remaining; - zone_movable_pfn[nid] = start_pfn + size_pages; - - /* - * Some kernelcore has been met, update counts and - * break if the kernelcore for this node has been - * satisfied - */ - required_kernelcore -= min(required_kernelcore, - size_pages); - kernelcore_remaining -= size_pages; - if (!kernelcore_remaining) - break; - } - } + struct per_cpu_pages *pcp; + struct cpu_cacheinfo *cci; + pcp = per_cpu_ptr(zone->per_cpu_pageset, cpu); + cci = get_cpu_cacheinfo(cpu); /* - * If there is still required_kernelcore, we do another pass with one - * less node in the count. This will push zone_movable_pfn[nid] further - * along on the nodes that still have memory until kernelcore is - * satisfied + * If data cache slice of CPU is large enough, "pcp->batch" + * pages can be preserved in PCP before draining PCP for + * consecutive high-order pages freeing without allocation. + * This can reduce zone lock contention without hurting + * cache-hot pages sharing. */ - usable_nodes--; - if (usable_nodes && required_kernelcore > usable_nodes) - goto restart; - -out2: - /* Align start of ZONE_MOVABLE on all nids to MAX_ORDER_NR_PAGES */ - for (nid = 0; nid < MAX_NUMNODES; nid++) - zone_movable_pfn[nid] = - roundup(zone_movable_pfn[nid], MAX_ORDER_NR_PAGES); - -out: - /* restore the node_state */ - node_states[N_MEMORY] = saved_node_state; + spin_lock(&pcp->lock); + if ((cci->per_cpu_data_slice_size >> PAGE_SHIFT) > 3 * pcp->batch) + pcp->flags |= PCPF_FREE_HIGH_BATCH; + else + pcp->flags &= ~PCPF_FREE_HIGH_BATCH; + spin_unlock(&pcp->lock); } -/* Any regular or high memory on that node ? */ -static void check_for_memory(pg_data_t *pgdat, int nid) +void setup_pcp_cacheinfo(unsigned int cpu) { - enum zone_type zone_type; + struct zone *zone; - for (zone_type = 0; zone_type <= ZONE_MOVABLE - 1; zone_type++) { - struct zone *zone = &pgdat->node_zones[zone_type]; - if (populated_zone(zone)) { - if (IS_ENABLED(CONFIG_HIGHMEM)) - node_set_state(nid, N_HIGH_MEMORY); - if (zone_type <= ZONE_NORMAL) - node_set_state(nid, N_NORMAL_MEMORY); - break; - } - } + for_each_populated_zone(zone) + zone_pcp_update_cacheinfo(zone, cpu); } -/** - * free_area_init_nodes - Initialise all pg_data_t and zone data - * @max_zone_pfn: an array of max PFNs for each zone - * - * This will call free_area_init_node() for each active node in the system. - * Using the page ranges provided by memblock_set_node(), the size of each - * zone in each node and their holes is calculated. If the maximum PFN - * between two adjacent zones match, it is assumed that the zone is empty. - * For example, if arch_max_dma_pfn == arch_max_dma32_pfn, it is assumed - * that arch_max_dma32_pfn has no pages. It is also assumed that a zone - * starts where the previous one ended. For example, ZONE_DMA32 starts - * at arch_max_dma_pfn. +/* + * Allocate per cpu pagesets and initialize them. + * Before this call only boot pagesets were available. */ -void __init free_area_init_nodes(unsigned long *max_zone_pfn) +void __init setup_per_cpu_pageset(void) { - unsigned long start_pfn, end_pfn; - int i, nid; - - /* Record where the zone boundaries are */ - memset(arch_zone_lowest_possible_pfn, 0, - sizeof(arch_zone_lowest_possible_pfn)); - memset(arch_zone_highest_possible_pfn, 0, - sizeof(arch_zone_highest_possible_pfn)); - - start_pfn = find_min_pfn_with_active_regions(); - - for (i = 0; i < MAX_NR_ZONES; i++) { - if (i == ZONE_MOVABLE) - continue; - - end_pfn = max(max_zone_pfn[i], start_pfn); - arch_zone_lowest_possible_pfn[i] = start_pfn; - arch_zone_highest_possible_pfn[i] = end_pfn; - - start_pfn = end_pfn; - } - - /* Find the PFNs that ZONE_MOVABLE begins at in each node */ - memset(zone_movable_pfn, 0, sizeof(zone_movable_pfn)); - find_zone_movable_pfns_for_nodes(); - - /* Print out the zone ranges */ - pr_info("Zone ranges:\n"); - for (i = 0; i < MAX_NR_ZONES; i++) { - if (i == ZONE_MOVABLE) - continue; - pr_info(" %-8s ", zone_names[i]); - if (arch_zone_lowest_possible_pfn[i] == - arch_zone_highest_possible_pfn[i]) - pr_cont("empty\n"); - else - pr_cont("[mem %#018Lx-%#018Lx]\n", - (u64)arch_zone_lowest_possible_pfn[i] - << PAGE_SHIFT, - ((u64)arch_zone_highest_possible_pfn[i] - << PAGE_SHIFT) - 1); - } - - /* Print out the PFNs ZONE_MOVABLE begins at in each node */ - pr_info("Movable zone start for each node\n"); - for (i = 0; i < MAX_NUMNODES; i++) { - if (zone_movable_pfn[i]) - pr_info(" Node %d: %#018Lx\n", i, - (u64)zone_movable_pfn[i] << PAGE_SHIFT); - } - - /* Print out the early node map */ - pr_info("Early memory node ranges\n"); - for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, &nid) - pr_info(" node %3d: [mem %#018Lx-%#018Lx]\n", nid, - (u64)start_pfn << PAGE_SHIFT, - ((u64)end_pfn << PAGE_SHIFT) - 1); + struct pglist_data *pgdat; + struct zone *zone; + int __maybe_unused cpu; - /* Initialise every node */ - mminit_verify_pageflags_layout(); - setup_nr_node_ids(); - zero_resv_unavail(); - for_each_online_node(nid) { - pg_data_t *pgdat = NODE_DATA(nid); - free_area_init_node(nid, NULL, - find_min_pfn_for_node(nid), NULL); + for_each_populated_zone(zone) + setup_zone_pageset(zone); - /* Any memory on that node */ - if (pgdat->node_present_pages) - node_set_state(nid, N_MEMORY); - check_for_memory(pgdat, nid); +#ifdef CONFIG_NUMA + /* + * Unpopulated zones continue using the boot pagesets. + * The numa stats for these pagesets need to be reset. + * Otherwise, they will end up skewing the stats of + * the nodes these zones are associated with. + */ + for_each_possible_cpu(cpu) { + struct per_cpu_zonestat *pzstats = &per_cpu(boot_zonestats, cpu); + memset(pzstats->vm_numa_event, 0, + sizeof(pzstats->vm_numa_event)); } -} - -static int __init cmdline_parse_core(char *p, unsigned long *core, - unsigned long *percent) -{ - unsigned long long coremem; - char *endptr; - - if (!p) - return -EINVAL; - - /* Value may be a percentage of total memory, otherwise bytes */ - coremem = simple_strtoull(p, &endptr, 0); - if (*endptr == '%') { - /* Paranoid check for percent values greater than 100 */ - WARN_ON(coremem > 100); - - *percent = coremem; - } else { - coremem = memparse(p, &p); - /* Paranoid check that UL is enough for the coremem value */ - WARN_ON((coremem >> PAGE_SHIFT) > ULONG_MAX); +#endif - *core = coremem >> PAGE_SHIFT; - *percent = 0UL; - } - return 0; + for_each_online_pgdat(pgdat) + pgdat->per_cpu_nodestats = + alloc_percpu(struct per_cpu_nodestat); } -/* - * kernelcore=size sets the amount of memory for use for allocations that - * cannot be reclaimed or migrated. - */ -static int __init cmdline_parse_kernelcore(char *p) +__meminit void zone_pcp_init(struct zone *zone) { - /* parse kernelcore=mirror */ - if (parse_option_str(p, "mirror")) { - mirrored_kernelcore = true; - return 0; - } - - return cmdline_parse_core(p, &required_kernelcore, - &required_kernelcore_percent); -} + /* + * per cpu subsystem is not up at this point. The following code + * relies on the ability of the linker to provide the + * offset of a (static) per cpu variable into the per cpu area. + */ + zone->per_cpu_pageset = &boot_pageset; + zone->per_cpu_zonestats = &boot_zonestats; + zone->pageset_high_min = BOOT_PAGESET_HIGH; + zone->pageset_high_max = BOOT_PAGESET_HIGH; + zone->pageset_batch = BOOT_PAGESET_BATCH; -/* - * movablecore=size sets the amount of memory for use for allocations that - * can be reclaimed or migrated. - */ -static int __init cmdline_parse_movablecore(char *p) -{ - return cmdline_parse_core(p, &required_movablecore, - &required_movablecore_percent); + if (populated_zone(zone)) + pr_debug(" %s zone: %lu pages, LIFO batch:%u\n", zone->name, + zone->present_pages, zone_batchsize(zone)); } -early_param("kernelcore", cmdline_parse_kernelcore); -early_param("movablecore", cmdline_parse_movablecore); - -#endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */ +static void setup_per_zone_lowmem_reserve(void); void adjust_managed_page_count(struct page *page, long count) { atomic_long_add(count, &page_zone(page)->managed_pages); totalram_pages_add(count); -#ifdef CONFIG_HIGHMEM - if (PageHighMem(page)) - totalhigh_pages_add(count); -#endif + setup_per_zone_lowmem_reserve(); } EXPORT_SYMBOL(adjust_managed_page_count); @@ -7255,6 +6214,11 @@ unsigned long free_reserved_area(void *start, void *end, int poison, const char * alias for the memset(). */ direct_map_addr = page_address(page); + /* + * Perform a kasan-unchecked memset() since this memory + * has not been initialized. + */ + direct_map_addr = kasan_reset_tag(direct_map_addr); if ((unsigned int)poison <= 0xFF) memset(direct_map_addr, poison, PAGE_SIZE); @@ -7262,103 +6226,27 @@ unsigned long free_reserved_area(void *start, void *end, int poison, const char } if (pages && s) - pr_info("Freeing %s memory: %ldK\n", - s, pages << (PAGE_SHIFT - 10)); + pr_info("Freeing %s memory: %ldK\n", s, K(pages)); return pages; } -EXPORT_SYMBOL(free_reserved_area); - -#ifdef CONFIG_HIGHMEM -void free_highmem_page(struct page *page) -{ - __free_reserved_page(page); - totalram_pages_inc(); - atomic_long_inc(&page_zone(page)->managed_pages); - totalhigh_pages_inc(); -} -#endif - - -void __init mem_init_print_info(const char *str) -{ - unsigned long physpages, codesize, datasize, rosize, bss_size; - unsigned long init_code_size, init_data_size; - - physpages = get_num_physpages(); - codesize = _etext - _stext; - datasize = _edata - _sdata; - rosize = __end_rodata - __start_rodata; - bss_size = __bss_stop - __bss_start; - init_data_size = __init_end - __init_begin; - init_code_size = _einittext - _sinittext; - - /* - * Detect special cases and adjust section sizes accordingly: - * 1) .init.* may be embedded into .data sections - * 2) .init.text.* may be out of [__init_begin, __init_end], - * please refer to arch/tile/kernel/vmlinux.lds.S. - * 3) .rodata.* may be embedded into .text or .data sections. - */ -#define adj_init_size(start, end, size, pos, adj) \ - do { \ - if (start <= pos && pos < end && size > adj) \ - size -= adj; \ - } while (0) - - adj_init_size(__init_begin, __init_end, init_data_size, - _sinittext, init_code_size); - adj_init_size(_stext, _etext, codesize, _sinittext, init_code_size); - adj_init_size(_sdata, _edata, datasize, __init_begin, init_data_size); - adj_init_size(_stext, _etext, codesize, __start_rodata, rosize); - adj_init_size(_sdata, _edata, datasize, __start_rodata, rosize); - -#undef adj_init_size - - pr_info("Memory: %luK/%luK available (%luK kernel code, %luK rwdata, %luK rodata, %luK init, %luK bss, %luK reserved, %luK cma-reserved" -#ifdef CONFIG_HIGHMEM - ", %luK highmem" -#endif - "%s%s)\n", - nr_free_pages() << (PAGE_SHIFT - 10), - physpages << (PAGE_SHIFT - 10), - codesize >> 10, datasize >> 10, rosize >> 10, - (init_data_size + init_code_size) >> 10, bss_size >> 10, - (physpages - totalram_pages() - totalcma_pages) << (PAGE_SHIFT - 10), - totalcma_pages << (PAGE_SHIFT - 10), -#ifdef CONFIG_HIGHMEM - totalhigh_pages() << (PAGE_SHIFT - 10), -#endif - str ? ", " : "", str ? str : ""); -} - -/** - * set_dma_reserve - set the specified number of pages reserved in the first zone - * @new_dma_reserve: The number of pages to mark reserved - * - * The per-cpu batchsize and zone watermarks are determined by managed_pages. - * In the DMA zone, a significant percentage may be consumed by kernel image - * and other unfreeable allocations which can skew the watermarks badly. This - * function may optionally be used to account for unfreeable pages in the - * first zone (e.g., ZONE_DMA). The effect will be lower watermarks and - * smaller per-cpu batchsize. - */ -void __init set_dma_reserve(unsigned long new_dma_reserve) -{ - dma_reserve = new_dma_reserve; -} -void __init free_area_init(unsigned long *zones_size) +void free_reserved_page(struct page *page) { - zero_resv_unavail(); - free_area_init_node(0, zones_size, - __pa(PAGE_OFFSET) >> PAGE_SHIFT, NULL); + clear_page_tag_ref(page); + ClearPageReserved(page); + init_page_count(page); + __free_page(page); + adjust_managed_page_count(page, 1); } +EXPORT_SYMBOL(free_reserved_page); static int page_alloc_cpu_dead(unsigned int cpu) { + struct zone *zone; lru_add_drain_cpu(cpu); + mlock_drain_remote(cpu); drain_pages(cpu); /* @@ -7377,15 +6265,29 @@ static int page_alloc_cpu_dead(unsigned int cpu) * race with what we are doing. */ cpu_vm_stats_fold(cpu); + + for_each_populated_zone(zone) + zone_pcp_update(zone, 0); + return 0; } -void __init page_alloc_init(void) +static int page_alloc_cpu_online(unsigned int cpu) +{ + struct zone *zone; + + for_each_populated_zone(zone) + zone_pcp_update(zone, 1); + return 0; +} + +void __init page_alloc_init_cpuhp(void) { int ret; - ret = cpuhp_setup_state_nocalls(CPUHP_PAGE_ALLOC_DEAD, - "mm/page_alloc:dead", NULL, + ret = cpuhp_setup_state_nocalls(CPUHP_PAGE_ALLOC, + "mm/page_alloc:pcp", + page_alloc_cpu_online, page_alloc_cpu_dead); WARN_ON(ret < 0); } @@ -7409,17 +6311,25 @@ static void calculate_totalreserve_pages(void) long max = 0; unsigned long managed_pages = zone_managed_pages(zone); - /* Find valid and maximum lowmem_reserve in the zone */ - for (j = i; j < MAX_NR_ZONES; j++) { - if (zone->lowmem_reserve[j] > max) - max = zone->lowmem_reserve[j]; - } + /* + * lowmem_reserve[j] is monotonically non-decreasing + * in j for a given zone (see + * setup_per_zone_lowmem_reserve()). The maximum + * valid reserve lives at the highest index with a + * non-zero value, so scan backwards and stop at the + * first hit. + */ + for (j = MAX_NR_ZONES - 1; j > i; j--) { + if (!zone->lowmem_reserve[j]) + continue; + max = zone->lowmem_reserve[j]; + break; + } /* we treat the high watermark as reserved pages. */ max += high_wmark_pages(zone); - if (max > managed_pages) - max = managed_pages; + max = min_t(unsigned long, max, managed_pages); pgdat->totalreserve_pages += max; @@ -7427,6 +6337,7 @@ static void calculate_totalreserve_pages(void) } } totalreserve_pages = reserve_pages; + trace_mm_calculate_totalreserve_pages(totalreserve_pages); } /* @@ -7438,30 +6349,40 @@ static void calculate_totalreserve_pages(void) static void setup_per_zone_lowmem_reserve(void) { struct pglist_data *pgdat; - enum zone_type j, idx; - + enum zone_type i, j; + /* + * For a given zone node_zones[i], lowmem_reserve[j] (j > i) + * represents how many pages in zone i must effectively be kept + * in reserve when deciding whether an allocation class that is + * allowed to allocate from zones up to j may fall back into + * zone i. + * + * As j increases, the allocation class can use a strictly larger + * set of fallback zones and therefore must not be allowed to + * deplete low zones more aggressively than a less flexible one. + * As a result, lowmem_reserve[j] is required to be monotonically + * non-decreasing in j for each zone i. Callers such as + * calculate_totalreserve_pages() rely on this monotonicity when + * selecting the maximum reserve entry. + */ for_each_online_pgdat(pgdat) { - for (j = 0; j < MAX_NR_ZONES; j++) { - struct zone *zone = pgdat->node_zones + j; - unsigned long managed_pages = zone_managed_pages(zone); - - zone->lowmem_reserve[j] = 0; - - idx = j; - while (idx) { - struct zone *lower_zone; - - idx--; - lower_zone = pgdat->node_zones + idx; - - if (sysctl_lowmem_reserve_ratio[idx] < 1) { - sysctl_lowmem_reserve_ratio[idx] = 0; - lower_zone->lowmem_reserve[j] = 0; - } else { - lower_zone->lowmem_reserve[j] = - managed_pages / sysctl_lowmem_reserve_ratio[idx]; - } - managed_pages += zone_managed_pages(lower_zone); + for (i = 0; i < MAX_NR_ZONES - 1; i++) { + struct zone *zone = &pgdat->node_zones[i]; + int ratio = sysctl_lowmem_reserve_ratio[i]; + bool clear = !ratio || !zone_managed_pages(zone); + unsigned long managed_pages = 0; + + for (j = i + 1; j < MAX_NR_ZONES; j++) { + struct zone *upper_zone = &pgdat->node_zones[j]; + + managed_pages += zone_managed_pages(upper_zone); + + if (clear) + zone->lowmem_reserve[j] = 0; + else + zone->lowmem_reserve[j] = managed_pages / ratio; + trace_mm_setup_per_zone_lowmem_reserve(zone, upper_zone, + zone->lowmem_reserve[j]); } } } @@ -7477,9 +6398,9 @@ static void __setup_per_zone_wmarks(void) struct zone *zone; unsigned long flags; - /* Calculate total number of !ZONE_HIGHMEM pages */ + /* Calculate total number of !ZONE_HIGHMEM and !ZONE_MOVABLE pages */ for_each_zone(zone) { - if (!is_highmem(zone)) + if (!is_highmem(zone) && zone_idx(zone) != ZONE_MOVABLE) lowmem_pages += zone_managed_pages(zone); } @@ -7488,16 +6409,16 @@ static void __setup_per_zone_wmarks(void) spin_lock_irqsave(&zone->lock, flags); tmp = (u64)pages_min * zone_managed_pages(zone); - do_div(tmp, lowmem_pages); - if (is_highmem(zone)) { + tmp = div64_ul(tmp, lowmem_pages); + if (is_highmem(zone) || zone_idx(zone) == ZONE_MOVABLE) { /* * __GFP_HIGH and PF_MEMALLOC allocations usually don't - * need highmem pages, so cap pages_min to a small - * value here. + * need highmem and movable zones pages, so cap pages_min + * to a small value here. * * The WMARK_HIGH-WMARK_LOW and (WMARK_LOW-WMARK_MIN) - * deltas control asynch page reclaim, and so should - * not be capped for highmem. + * deltas control async page reclaim, and so should + * not be capped for highmem and movable zones. */ unsigned long min_pages; @@ -7521,9 +6442,11 @@ static void __setup_per_zone_wmarks(void) mult_frac(zone_managed_pages(zone), watermark_scale_factor, 10000)); - zone->_watermark[WMARK_LOW] = min_wmark_pages(zone) + tmp; - zone->_watermark[WMARK_HIGH] = min_wmark_pages(zone) + tmp * 2; zone->watermark_boost = 0; + zone->_watermark[WMARK_LOW] = min_wmark_pages(zone) + tmp; + zone->_watermark[WMARK_HIGH] = low_wmark_pages(zone) + tmp; + zone->_watermark[WMARK_PROMO] = high_wmark_pages(zone) + tmp; + trace_mm_setup_per_zone_wmarks(zone); spin_unlock_irqrestore(&zone->lock, flags); } @@ -7541,18 +6464,26 @@ static void __setup_per_zone_wmarks(void) */ void setup_per_zone_wmarks(void) { + struct zone *zone; static DEFINE_SPINLOCK(lock); spin_lock(&lock); __setup_per_zone_wmarks(); spin_unlock(&lock); + + /* + * The watermark size have changed so update the pcpu batch + * and high limits or the limits may be inappropriate. + */ + for_each_zone(zone) + zone_pcp_update(zone, 0); } /* * Initialise min_free_kbytes. * * For small machines we want it small (128k min). For large machines - * we want it large (64MB max). But it is not linear, because network + * we want it large (256MB max). But it is not linear, because network * bandwidth does not increase linearly with machine size. We use * * min_free_kbytes = 4 * sqrt(lowmem_kbytes), for better accuracy: @@ -7572,7 +6503,7 @@ void setup_per_zone_wmarks(void) * 8192MB: 11584k * 16384MB: 16384k */ -int __meminit init_per_zone_wmark_min(void) +void calculate_min_free_kbytes(void) { unsigned long lowmem_kbytes; int new_min_free_kbytes; @@ -7580,16 +6511,17 @@ int __meminit init_per_zone_wmark_min(void) lowmem_kbytes = nr_free_buffer_pages() * (PAGE_SIZE >> 10); new_min_free_kbytes = int_sqrt(lowmem_kbytes * 16); - if (new_min_free_kbytes > user_min_free_kbytes) { - min_free_kbytes = new_min_free_kbytes; - if (min_free_kbytes < 128) - min_free_kbytes = 128; - if (min_free_kbytes > 65536) - min_free_kbytes = 65536; - } else { + if (new_min_free_kbytes > user_min_free_kbytes) + min_free_kbytes = clamp(new_min_free_kbytes, 128, 262144); + else pr_warn("min_free_kbytes is not updated to %d because user defined value %d is preferred\n", new_min_free_kbytes, user_min_free_kbytes); - } + +} + +int __meminit init_per_zone_wmark_min(void) +{ + calculate_min_free_kbytes(); setup_per_zone_wmarks(); refresh_zone_stat_thresholds(); setup_per_zone_lowmem_reserve(); @@ -7599,17 +6531,19 @@ int __meminit init_per_zone_wmark_min(void) setup_min_slab_ratio(); #endif + khugepaged_min_free_kbytes_update(); + return 0; } -core_initcall(init_per_zone_wmark_min) +postcore_initcall(init_per_zone_wmark_min) /* * min_free_kbytes_sysctl_handler - just a wrapper around proc_dointvec() so * that we can call two helper functions whenever min_free_kbytes * changes. */ -int min_free_kbytes_sysctl_handler(struct ctl_table *table, int write, - void __user *buffer, size_t *length, loff_t *ppos) +static int min_free_kbytes_sysctl_handler(const struct ctl_table *table, int write, + void *buffer, size_t *length, loff_t *ppos) { int rc; @@ -7624,20 +6558,8 @@ int min_free_kbytes_sysctl_handler(struct ctl_table *table, int write, return 0; } -int watermark_boost_factor_sysctl_handler(struct ctl_table *table, int write, - void __user *buffer, size_t *length, loff_t *ppos) -{ - int rc; - - rc = proc_dointvec_minmax(table, write, buffer, length, ppos); - if (rc) - return rc; - - return 0; -} - -int watermark_scale_factor_sysctl_handler(struct ctl_table *table, int write, - void __user *buffer, size_t *length, loff_t *ppos) +static int watermark_scale_factor_sysctl_handler(const struct ctl_table *table, int write, + void *buffer, size_t *length, loff_t *ppos) { int rc; @@ -7666,8 +6588,8 @@ static void setup_min_unmapped_ratio(void) } -int sysctl_min_unmapped_ratio_sysctl_handler(struct ctl_table *table, int write, - void __user *buffer, size_t *length, loff_t *ppos) +static int sysctl_min_unmapped_ratio_sysctl_handler(const struct ctl_table *table, int write, + void *buffer, size_t *length, loff_t *ppos) { int rc; @@ -7693,8 +6615,8 @@ static void setup_min_slab_ratio(void) sysctl_min_slab_ratio) / 100; } -int sysctl_min_slab_ratio_sysctl_handler(struct ctl_table *table, int write, - void __user *buffer, size_t *length, loff_t *ppos) +static int sysctl_min_slab_ratio_sysctl_handler(const struct ctl_table *table, int write, + void *buffer, size_t *length, loff_t *ppos) { int rc; @@ -7717,337 +6639,157 @@ int sysctl_min_slab_ratio_sysctl_handler(struct ctl_table *table, int write, * minimum watermarks. The lowmem reserve ratio can only make sense * if in function of the boot time zone sizes. */ -int lowmem_reserve_ratio_sysctl_handler(struct ctl_table *table, int write, - void __user *buffer, size_t *length, loff_t *ppos) +static int lowmem_reserve_ratio_sysctl_handler(const struct ctl_table *table, + int write, void *buffer, size_t *length, loff_t *ppos) { + int i; + proc_dointvec_minmax(table, write, buffer, length, ppos); + + for (i = 0; i < MAX_NR_ZONES; i++) { + if (sysctl_lowmem_reserve_ratio[i] < 1) + sysctl_lowmem_reserve_ratio[i] = 0; + } + setup_per_zone_lowmem_reserve(); return 0; } /* - * percpu_pagelist_fraction - changes the pcp->high for each zone on each - * cpu. It is the fraction of total pages in each zone that a hot per cpu + * percpu_pagelist_high_fraction - changes the pcp->high for each zone on each + * cpu. It is the fraction of total pages in each zone that a hot per cpu * pagelist can have before it gets flushed back to buddy allocator. */ -int percpu_pagelist_fraction_sysctl_handler(struct ctl_table *table, int write, - void __user *buffer, size_t *length, loff_t *ppos) +static int percpu_pagelist_high_fraction_sysctl_handler(const struct ctl_table *table, + int write, void *buffer, size_t *length, loff_t *ppos) { struct zone *zone; - int old_percpu_pagelist_fraction; + int old_percpu_pagelist_high_fraction; int ret; mutex_lock(&pcp_batch_high_lock); - old_percpu_pagelist_fraction = percpu_pagelist_fraction; + old_percpu_pagelist_high_fraction = percpu_pagelist_high_fraction; ret = proc_dointvec_minmax(table, write, buffer, length, ppos); if (!write || ret < 0) goto out; /* Sanity checking to avoid pcp imbalance */ - if (percpu_pagelist_fraction && - percpu_pagelist_fraction < MIN_PERCPU_PAGELIST_FRACTION) { - percpu_pagelist_fraction = old_percpu_pagelist_fraction; + if (percpu_pagelist_high_fraction && + percpu_pagelist_high_fraction < MIN_PERCPU_PAGELIST_HIGH_FRACTION) { + percpu_pagelist_high_fraction = old_percpu_pagelist_high_fraction; ret = -EINVAL; goto out; } /* No change? */ - if (percpu_pagelist_fraction == old_percpu_pagelist_fraction) + if (percpu_pagelist_high_fraction == old_percpu_pagelist_high_fraction) goto out; - for_each_populated_zone(zone) { - unsigned int cpu; - - for_each_possible_cpu(cpu) - pageset_set_high_and_batch(zone, - per_cpu_ptr(zone->pageset, cpu)); - } + for_each_populated_zone(zone) + zone_set_pageset_high_and_batch(zone, 0); out: mutex_unlock(&pcp_batch_high_lock); return ret; } +static const struct ctl_table page_alloc_sysctl_table[] = { + { + .procname = "min_free_kbytes", + .data = &min_free_kbytes, + .maxlen = sizeof(min_free_kbytes), + .mode = 0644, + .proc_handler = min_free_kbytes_sysctl_handler, + .extra1 = SYSCTL_ZERO, + }, + { + .procname = "watermark_boost_factor", + .data = &watermark_boost_factor, + .maxlen = sizeof(watermark_boost_factor), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = SYSCTL_ZERO, + }, + { + .procname = "watermark_scale_factor", + .data = &watermark_scale_factor, + .maxlen = sizeof(watermark_scale_factor), + .mode = 0644, + .proc_handler = watermark_scale_factor_sysctl_handler, + .extra1 = SYSCTL_ONE, + .extra2 = SYSCTL_THREE_THOUSAND, + }, + { + .procname = "defrag_mode", + .data = &defrag_mode, + .maxlen = sizeof(defrag_mode), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = SYSCTL_ZERO, + .extra2 = SYSCTL_ONE, + }, + { + .procname = "percpu_pagelist_high_fraction", + .data = &percpu_pagelist_high_fraction, + .maxlen = sizeof(percpu_pagelist_high_fraction), + .mode = 0644, + .proc_handler = percpu_pagelist_high_fraction_sysctl_handler, + .extra1 = SYSCTL_ZERO, + }, + { + .procname = "lowmem_reserve_ratio", + .data = &sysctl_lowmem_reserve_ratio, + .maxlen = sizeof(sysctl_lowmem_reserve_ratio), + .mode = 0644, + .proc_handler = lowmem_reserve_ratio_sysctl_handler, + }, #ifdef CONFIG_NUMA -int hashdist = HASHDIST_DEFAULT; - -static int __init set_hashdist(char *str) -{ - if (!str) - return 0; - hashdist = simple_strtoul(str, &str, 0); - return 1; -} -__setup("hashdist=", set_hashdist); + { + .procname = "numa_zonelist_order", + .data = &numa_zonelist_order, + .maxlen = NUMA_ZONELIST_ORDER_LEN, + .mode = 0644, + .proc_handler = numa_zonelist_order_handler, + }, + { + .procname = "min_unmapped_ratio", + .data = &sysctl_min_unmapped_ratio, + .maxlen = sizeof(sysctl_min_unmapped_ratio), + .mode = 0644, + .proc_handler = sysctl_min_unmapped_ratio_sysctl_handler, + .extra1 = SYSCTL_ZERO, + .extra2 = SYSCTL_ONE_HUNDRED, + }, + { + .procname = "min_slab_ratio", + .data = &sysctl_min_slab_ratio, + .maxlen = sizeof(sysctl_min_slab_ratio), + .mode = 0644, + .proc_handler = sysctl_min_slab_ratio_sysctl_handler, + .extra1 = SYSCTL_ZERO, + .extra2 = SYSCTL_ONE_HUNDRED, + }, #endif +}; -#ifndef __HAVE_ARCH_RESERVED_KERNEL_PAGES -/* - * Returns the number of pages that arch has reserved but - * is not known to alloc_large_system_hash(). - */ -static unsigned long __init arch_reserved_kernel_pages(void) +void __init page_alloc_sysctl_init(void) { - return 0; + register_sysctl_init("vm", page_alloc_sysctl_table); } -#endif - -/* - * Adaptive scale is meant to reduce sizes of hash tables on large memory - * machines. As memory size is increased the scale is also increased but at - * slower pace. Starting from ADAPT_SCALE_BASE (64G), every time memory - * quadruples the scale is increased by one, which means the size of hash table - * only doubles, instead of quadrupling as well. - * Because 32-bit systems cannot have large physical memory, where this scaling - * makes sense, it is disabled on such platforms. - */ -#if __BITS_PER_LONG > 32 -#define ADAPT_SCALE_BASE (64ul << 30) -#define ADAPT_SCALE_SHIFT 2 -#define ADAPT_SCALE_NPAGES (ADAPT_SCALE_BASE >> PAGE_SHIFT) -#endif - -/* - * allocate a large system hash table from bootmem - * - it is assumed that the hash table must contain an exact power-of-2 - * quantity of entries - * - limit is the number of hash buckets, not the total allocation size - */ -void *__init alloc_large_system_hash(const char *tablename, - unsigned long bucketsize, - unsigned long numentries, - int scale, - int flags, - unsigned int *_hash_shift, - unsigned int *_hash_mask, - unsigned long low_limit, - unsigned long high_limit) -{ - unsigned long long max = high_limit; - unsigned long log2qty, size; - void *table = NULL; - gfp_t gfp_flags; - - /* allow the kernel cmdline to have a say */ - if (!numentries) { - /* round applicable memory size up to nearest megabyte */ - numentries = nr_kernel_pages; - numentries -= arch_reserved_kernel_pages(); - - /* It isn't necessary when PAGE_SIZE >= 1MB */ - if (PAGE_SHIFT < 20) - numentries = round_up(numentries, (1<<20)/PAGE_SIZE); - -#if __BITS_PER_LONG > 32 - if (!high_limit) { - unsigned long adapt; - - for (adapt = ADAPT_SCALE_NPAGES; adapt < numentries; - adapt <<= ADAPT_SCALE_SHIFT) - scale++; - } -#endif - - /* limit to 1 bucket per 2^scale bytes of low memory */ - if (scale > PAGE_SHIFT) - numentries >>= (scale - PAGE_SHIFT); - else - numentries <<= (PAGE_SHIFT - scale); - - /* Make sure we've got at least a 0-order allocation.. */ - if (unlikely(flags & HASH_SMALL)) { - /* Makes no sense without HASH_EARLY */ - WARN_ON(!(flags & HASH_EARLY)); - if (!(numentries >> *_hash_shift)) { - numentries = 1UL << *_hash_shift; - BUG_ON(!numentries); - } - } else if (unlikely((numentries * bucketsize) < PAGE_SIZE)) - numentries = PAGE_SIZE / bucketsize; - } - numentries = roundup_pow_of_two(numentries); - - /* limit allocation size to 1/16 total memory by default */ - if (max == 0) { - max = ((unsigned long long)nr_all_pages << PAGE_SHIFT) >> 4; - do_div(max, bucketsize); - } - max = min(max, 0x80000000ULL); - - if (numentries < low_limit) - numentries = low_limit; - if (numentries > max) - numentries = max; - - log2qty = ilog2(numentries); - gfp_flags = (flags & HASH_ZERO) ? GFP_ATOMIC | __GFP_ZERO : GFP_ATOMIC; - do { - size = bucketsize << log2qty; - if (flags & HASH_EARLY) { - if (flags & HASH_ZERO) - table = memblock_alloc_nopanic(size, - SMP_CACHE_BYTES); - else - table = memblock_alloc_raw(size, - SMP_CACHE_BYTES); - } else if (hashdist) { - table = __vmalloc(size, gfp_flags, PAGE_KERNEL); - } else { - /* - * If bucketsize is not a power-of-two, we may free - * some pages at the end of hash table which - * alloc_pages_exact() automatically does - */ - if (get_order(size) < MAX_ORDER) { - table = alloc_pages_exact(size, gfp_flags); - kmemleak_alloc(table, size, 1, gfp_flags); - } - } - } while (!table && size > PAGE_SIZE && --log2qty); - - if (!table) - panic("Failed to allocate %s hash table\n", tablename); - - pr_info("%s hash table entries: %ld (order: %d, %lu bytes)\n", - tablename, 1UL << log2qty, ilog2(size) - PAGE_SHIFT, size); - - if (_hash_shift) - *_hash_shift = log2qty; - if (_hash_mask) - *_hash_mask = (1 << log2qty) - 1; - - return table; -} - -/* - * This function checks whether pageblock includes unmovable pages or not. - * If @count is not zero, it is okay to include less @count unmovable pages - * - * PageLRU check without isolation or lru_lock could race so that - * MIGRATE_MOVABLE block might include unmovable pages. And __PageMovable - * check without lock_page also may miss some movable non-lru pages at - * race condition. So you can't expect this function should be exact. - */ -bool has_unmovable_pages(struct zone *zone, struct page *page, int count, - int migratetype, int flags) +#ifdef CONFIG_CONTIG_ALLOC +/* Usage: See admin-guide/dynamic-debug-howto.rst */ +static void alloc_contig_dump_pages(struct list_head *page_list) { - unsigned long pfn, iter, found; - - /* - * TODO we could make this much more efficient by not checking every - * page in the range if we know all of them are in MOVABLE_ZONE and - * that the movable zone guarantees that pages are migratable but - * the later is not the case right now unfortunatelly. E.g. movablecore - * can still lead to having bootmem allocations in zone_movable. - */ + DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, "migrate failure"); - /* - * CMA allocations (alloc_contig_range) really need to mark isolate - * CMA pageblocks even when they are not movable in fact so consider - * them movable here. - */ - if (is_migrate_cma(migratetype) && - is_migrate_cma(get_pageblock_migratetype(page))) - return false; - - pfn = page_to_pfn(page); - for (found = 0, iter = 0; iter < pageblock_nr_pages; iter++) { - unsigned long check = pfn + iter; - - if (!pfn_valid_within(check)) - continue; - - page = pfn_to_page(check); - - if (PageReserved(page)) - goto unmovable; - - /* - * If the zone is movable and we have ruled out all reserved - * pages then it should be reasonably safe to assume the rest - * is movable. - */ - if (zone_idx(zone) == ZONE_MOVABLE) - continue; - - /* - * Hugepages are not in LRU lists, but they're movable. - * We need not scan over tail pages bacause we don't - * handle each tail page individually in migration. - */ - if (PageHuge(page)) { - struct page *head = compound_head(page); - unsigned int skip_pages; - - if (!hugepage_migration_supported(page_hstate(head))) - goto unmovable; - - skip_pages = (1 << compound_order(head)) - (page - head); - iter += skip_pages - 1; - continue; - } - - /* - * We can't use page_count without pin a page - * because another CPU can free compound page. - * This check already skips compound tails of THP - * because their page->_refcount is zero at all time. - */ - if (!page_ref_count(page)) { - if (PageBuddy(page)) - iter += (1 << page_order(page)) - 1; - continue; - } - - /* - * The HWPoisoned page may be not in buddy system, and - * page_count() is not 0. - */ - if ((flags & SKIP_HWPOISON) && PageHWPoison(page)) - continue; - - if (__PageMovable(page)) - continue; + if (DYNAMIC_DEBUG_BRANCH(descriptor)) { + struct page *page; - if (!PageLRU(page)) - found++; - /* - * If there are RECLAIMABLE pages, we need to check - * it. But now, memory offline itself doesn't call - * shrink_node_slabs() and it still to be fixed. - */ - /* - * If the page is not RAM, page_count()should be 0. - * we don't need more check. This is an _used_ not-movable page. - * - * The problematic thing here is PG_reserved pages. PG_reserved - * is set to both of a memory hole page and a _used_ kernel - * page at boot. - */ - if (found > count) - goto unmovable; + dump_stack(); + list_for_each_entry(page, page_list, lru) + dump_page(page, "migration failure"); } - return false; -unmovable: - WARN_ON_ONCE(zone_idx(zone) == ZONE_MOVABLE); - if (flags & REPORT_FAILURE) - dump_page(pfn_to_page(pfn+iter), "unmovable page"); - return true; -} - -#if (defined(CONFIG_MEMORY_ISOLATION) && defined(CONFIG_COMPACTION)) || defined(CONFIG_CMA) - -static unsigned long pfn_max_align_down(unsigned long pfn) -{ - return pfn & ~(max_t(unsigned long, MAX_ORDER_NR_PAGES, - pageblock_nr_pages) - 1); -} - -static unsigned long pfn_max_align_up(unsigned long pfn) -{ - return ALIGN(pfn, max_t(unsigned long, MAX_ORDER_NR_PAGES, - pageblock_nr_pages)); } /* [start, end) must belong to a single zone. */ @@ -8055,12 +6797,17 @@ static int __alloc_contig_migrate_range(struct compact_control *cc, unsigned long start, unsigned long end) { /* This function is based on compact_zone() from compaction.c. */ - unsigned long nr_reclaimed; + unsigned int nr_reclaimed; unsigned long pfn = start; unsigned int tries = 0; int ret = 0; + struct migration_target_control mtc = { + .nid = zone_to_nid(cc->zone), + .gfp_mask = cc->gfp_mask, + .reason = MR_CONTIG_RANGE, + }; - migrate_prep(); + lru_cache_disable(); while (pfn < end || !list_empty(&cc->migratepages)) { if (fatal_signal_pending(current)) { @@ -8070,14 +6817,13 @@ static int __alloc_contig_migrate_range(struct compact_control *cc, if (list_empty(&cc->migratepages)) { cc->nr_migratepages = 0; - pfn = isolate_migratepages_range(cc, pfn, end); - if (!pfn) { - ret = -EINTR; + ret = isolate_migratepages_range(cc, pfn, end); + if (ret && ret != -EAGAIN) break; - } + pfn = cc->migrate_pfn; tries = 0; } else if (++tries == 5) { - ret = ret < 0 ? ret : -EBUSY; + ret = -EBUSY; break; } @@ -8085,13 +6831,84 @@ static int __alloc_contig_migrate_range(struct compact_control *cc, &cc->migratepages); cc->nr_migratepages -= nr_reclaimed; - ret = migrate_pages(&cc->migratepages, alloc_migrate_target, - NULL, 0, cc->mode, MR_CONTIG_RANGE); + ret = migrate_pages(&cc->migratepages, alloc_migration_target, + NULL, (unsigned long)&mtc, cc->mode, MR_CONTIG_RANGE, NULL); + + /* + * On -ENOMEM, migrate_pages() bails out right away. It is pointless + * to retry again over this error, so do the same here. + */ + if (ret == -ENOMEM) + break; } + + lru_cache_enable(); if (ret < 0) { + if (!(cc->gfp_mask & __GFP_NOWARN) && ret == -EBUSY) + alloc_contig_dump_pages(&cc->migratepages); putback_movable_pages(&cc->migratepages); - return ret; } + + return (ret < 0) ? ret : 0; +} + +static void split_free_pages(struct list_head *list, gfp_t gfp_mask) +{ + int order; + + for (order = 0; order < NR_PAGE_ORDERS; order++) { + struct page *page, *next; + int nr_pages = 1 << order; + + list_for_each_entry_safe(page, next, &list[order], lru) { + int i; + + post_alloc_hook(page, order, gfp_mask); + set_page_refcounted(page); + if (!order) + continue; + + split_page(page, order); + + /* Add all subpages to the order-0 head, in sequence. */ + list_del(&page->lru); + for (i = 0; i < nr_pages; i++) + list_add_tail(&page[i].lru, &list[0]); + } + } +} + +static int __alloc_contig_verify_gfp_mask(gfp_t gfp_mask, gfp_t *gfp_cc_mask) +{ + const gfp_t reclaim_mask = __GFP_IO | __GFP_FS | __GFP_RECLAIM; + const gfp_t action_mask = __GFP_COMP | __GFP_RETRY_MAYFAIL | __GFP_NOWARN | + __GFP_ZERO | __GFP_ZEROTAGS | __GFP_SKIP_ZERO; + const gfp_t cc_action_mask = __GFP_RETRY_MAYFAIL | __GFP_NOWARN; + + /* + * We are given the range to allocate; node, mobility and placement + * hints are irrelevant at this point. We'll simply ignore them. + */ + gfp_mask &= ~(GFP_ZONEMASK | __GFP_RECLAIMABLE | __GFP_WRITE | + __GFP_HARDWALL | __GFP_THISNODE | __GFP_MOVABLE); + + /* + * We only support most reclaim flags (but not NOFAIL/NORETRY), and + * selected action flags. + */ + if (gfp_mask & ~(reclaim_mask | action_mask)) + return -EINVAL; + + /* + * Flags to control page compaction/migration/reclaim, to free up our + * page range. Migratable pages are movable, __GFP_MOVABLE is implied + * for them. + * + * Traditionally we always had __GFP_RETRY_MAYFAIL set, keep doing that + * to not degrade callers. + */ + *gfp_cc_mask = (gfp_mask & (reclaim_mask | cc_action_mask)) | + __GFP_MOVABLE | __GFP_RETRY_MAYFAIL; return 0; } @@ -8099,28 +6916,27 @@ static int __alloc_contig_migrate_range(struct compact_control *cc, * alloc_contig_range() -- tries to allocate given range of pages * @start: start PFN to allocate * @end: one-past-the-last PFN to allocate - * @migratetype: migratetype of the underlaying pageblocks (either - * #MIGRATE_MOVABLE or #MIGRATE_CMA). All pageblocks - * in range must have the same migratetype and it must - * be either of the two. - * @gfp_mask: GFP mask to use during compaction + * @alloc_flags: allocation information + * @gfp_mask: GFP mask. Node/zone/placement hints are ignored; only some + * action and reclaim modifiers are supported. Reclaim modifiers + * control allocation behavior during compaction/migration/reclaim. * - * The PFN range does not have to be pageblock or MAX_ORDER_NR_PAGES - * aligned. The PFN range must belong to a single zone. + * The PFN range does not have to be pageblock aligned. The PFN range must + * belong to a single zone. * * The first thing this routine does is attempt to MIGRATE_ISOLATE all * pageblocks in the range. Once isolated, the pageblocks should not * be modified by others. * - * Returns zero on success or negative error code. On success all + * Return: zero on success or negative error code. On success all * pages which PFN is in [start, end) are allocated for the caller and * need to be freed with free_contig_range(). */ -int alloc_contig_range(unsigned long start, unsigned long end, - unsigned migratetype, gfp_t gfp_mask) +int alloc_contig_range_noprof(unsigned long start, unsigned long end, + acr_flags_t alloc_flags, gfp_t gfp_mask) { + const unsigned int order = ilog2(end - start); unsigned long outer_start, outer_end; - unsigned int order; int ret = 0; struct compact_control cc = { @@ -8130,22 +6946,34 @@ int alloc_contig_range(unsigned long start, unsigned long end, .mode = MIGRATE_SYNC, .ignore_skip_hint = true, .no_set_skip_hint = true, - .gfp_mask = current_gfp_context(gfp_mask), + .alloc_contig = true, }; INIT_LIST_HEAD(&cc.migratepages); + enum pb_isolate_mode mode = (alloc_flags & ACR_FLAGS_CMA) ? + PB_ISOLATE_MODE_CMA_ALLOC : + PB_ISOLATE_MODE_OTHER; + + /* + * In contrast to the buddy, we allow for orders here that exceed + * MAX_PAGE_ORDER, so we must manually make sure that we are not + * exceeding the maximum folio order. + */ + if (WARN_ON_ONCE((gfp_mask & __GFP_COMP) && order > MAX_FOLIO_ORDER)) + return -EINVAL; + + gfp_mask = current_gfp_context(gfp_mask); + if (__alloc_contig_verify_gfp_mask(gfp_mask, (gfp_t *)&cc.gfp_mask)) + return -EINVAL; /* * What we do here is we mark all pageblocks in range as * MIGRATE_ISOLATE. Because pageblock and max order pages may * have different sizes, and due to the way page allocator - * work, we align the range to biggest of the two pages so - * that page allocator won't try to merge buddies from - * different pageblocks and change MIGRATE_ISOLATE to some - * other migration type. + * work, start_isolate_page_range() has special handlings for this. * * Once the pageblocks are marked as MIGRATE_ISOLATE, we * migrate the pages from an unaligned range (ie. pages that - * we are interested in). This will put all the pages in + * we are interested in). This will put all the pages in * range back to page allocator as MIGRATE_ISOLATE. * * When this is done, we take the pages in range from page @@ -8158,10 +6986,11 @@ int alloc_contig_range(unsigned long start, unsigned long end, * put back to page allocator so that buddy can use them. */ - ret = start_isolate_page_range(pfn_max_align_down(start), - pfn_max_align_up(end), migratetype, 0); + ret = start_isolate_page_range(start, end, mode); if (ret) - return ret; + goto done; + + drain_all_pages(cc.zone); /* * In case of -EBUSY, we'd like to know which page causes problem. @@ -8176,10 +7005,20 @@ int alloc_contig_range(unsigned long start, unsigned long end, ret = __alloc_contig_migrate_range(&cc, start, end); if (ret && ret != -EBUSY) goto done; - ret =0; /* - * Pages from [start, end) are within a MAX_ORDER_NR_PAGES + * When in-use hugetlb pages are migrated, they may simply be released + * back into the free hugepage pool instead of being returned to the + * buddy system. After the migration of in-use huge pages is completed, + * we will invoke replace_free_hugepage_folios() to ensure that these + * hugepages are properly released to the buddy system. + */ + ret = replace_free_hugepage_folios(start, end); + if (ret) + goto done; + + /* + * Pages from [start, end) are within a pageblock_nr_pages * aligned blocks that are marked as MIGRATE_ISOLATE. What's * more, all pages in [start, end) are free in page allocator. * What we are going to do is to allocate all pages from @@ -8194,37 +7033,10 @@ int alloc_contig_range(unsigned long start, unsigned long end, * We don't have to hold zone->lock here because the pages are * isolated thus they won't get removed from buddy. */ - - lru_add_drain_all(); - drain_all_pages(cc.zone); - - order = 0; - outer_start = start; - while (!PageBuddy(pfn_to_page(outer_start))) { - if (++order >= MAX_ORDER) { - outer_start = start; - break; - } - outer_start &= ~0UL << order; - } - - if (outer_start != start) { - order = page_order(pfn_to_page(outer_start)); - - /* - * outer_start page could be small order buddy page and - * it doesn't include start page. Adjust outer_start - * in this case to report failed page properly - * on tracepoint in test_pages_isolated() - */ - if (outer_start + (1UL << order) <= start) - outer_start = start; - } + outer_start = find_large_buddy(start); /* Make sure the range is really isolated. */ - if (test_pages_isolated(outer_start, end, false)) { - pr_info_ratelimited("%s: [%lx, %lx) PFNs busy\n", - __func__, outer_start, end); + if (test_pages_isolated(outer_start, end, mode)) { ret = -EBUSY; goto done; } @@ -8236,21 +7048,147 @@ int alloc_contig_range(unsigned long start, unsigned long end, goto done; } - /* Free head and tail (if any) */ - if (start != outer_start) - free_contig_range(outer_start, start - outer_start); - if (end != outer_end) - free_contig_range(end, outer_end - end); + if (!(gfp_mask & __GFP_COMP)) { + split_free_pages(cc.freepages, gfp_mask); + /* Free head and tail (if any) */ + if (start != outer_start) + free_contig_range(outer_start, start - outer_start); + if (end != outer_end) + free_contig_range(end, outer_end - end); + } else if (start == outer_start && end == outer_end && is_power_of_2(end - start)) { + struct page *head = pfn_to_page(start); + + check_new_pages(head, order); + prep_new_page(head, order, gfp_mask, 0); + set_page_refcounted(head); + } else { + ret = -EINVAL; + WARN(true, "PFN range: requested [%lu, %lu), allocated [%lu, %lu)\n", + start, end, outer_start, outer_end); + } done: - undo_isolate_page_range(pfn_max_align_down(start), - pfn_max_align_up(end), migratetype); + undo_isolate_page_range(start, end); return ret; } +EXPORT_SYMBOL(alloc_contig_range_noprof); + +static int __alloc_contig_pages(unsigned long start_pfn, + unsigned long nr_pages, gfp_t gfp_mask) +{ + unsigned long end_pfn = start_pfn + nr_pages; + + return alloc_contig_range_noprof(start_pfn, end_pfn, ACR_FLAGS_NONE, + gfp_mask); +} + +static bool pfn_range_valid_contig(struct zone *z, unsigned long start_pfn, + unsigned long nr_pages) +{ + unsigned long i, end_pfn = start_pfn + nr_pages; + struct page *page; + + for (i = start_pfn; i < end_pfn; i++) { + page = pfn_to_online_page(i); + if (!page) + return false; + + if (page_zone(page) != z) + return false; + + if (PageReserved(page)) + return false; + + if (PageHuge(page)) + return false; + } + return true; +} + +static bool zone_spans_last_pfn(const struct zone *zone, + unsigned long start_pfn, unsigned long nr_pages) +{ + unsigned long last_pfn = start_pfn + nr_pages - 1; + + return zone_spans_pfn(zone, last_pfn); +} -void free_contig_range(unsigned long pfn, unsigned nr_pages) +/** + * alloc_contig_pages() -- tries to find and allocate contiguous range of pages + * @nr_pages: Number of contiguous pages to allocate + * @gfp_mask: GFP mask. Node/zone/placement hints limit the search; only some + * action and reclaim modifiers are supported. Reclaim modifiers + * control allocation behavior during compaction/migration/reclaim. + * @nid: Target node + * @nodemask: Mask for other possible nodes + * + * This routine is a wrapper around alloc_contig_range(). It scans over zones + * on an applicable zonelist to find a contiguous pfn range which can then be + * tried for allocation with alloc_contig_range(). This routine is intended + * for allocation requests which can not be fulfilled with the buddy allocator. + * + * The allocated memory is always aligned to a page boundary. If nr_pages is a + * power of two, then allocated range is also guaranteed to be aligned to same + * nr_pages (e.g. 1GB request would be aligned to 1GB). + * + * Allocated pages can be freed with free_contig_range() or by manually calling + * __free_page() on each allocated page. + * + * Return: pointer to contiguous pages on success, or NULL if not successful. + */ +struct page *alloc_contig_pages_noprof(unsigned long nr_pages, gfp_t gfp_mask, + int nid, nodemask_t *nodemask) { - unsigned int count = 0; + unsigned long ret, pfn, flags; + struct zonelist *zonelist; + struct zone *zone; + struct zoneref *z; + + zonelist = node_zonelist(nid, gfp_mask); + for_each_zone_zonelist_nodemask(zone, z, zonelist, + gfp_zone(gfp_mask), nodemask) { + spin_lock_irqsave(&zone->lock, flags); + + pfn = ALIGN(zone->zone_start_pfn, nr_pages); + while (zone_spans_last_pfn(zone, pfn, nr_pages)) { + if (pfn_range_valid_contig(zone, pfn, nr_pages)) { + /* + * We release the zone lock here because + * alloc_contig_range() will also lock the zone + * at some point. If there's an allocation + * spinning on this lock, it may win the race + * and cause alloc_contig_range() to fail... + */ + spin_unlock_irqrestore(&zone->lock, flags); + ret = __alloc_contig_pages(pfn, nr_pages, + gfp_mask); + if (!ret) + return pfn_to_page(pfn); + spin_lock_irqsave(&zone->lock, flags); + } + pfn += nr_pages; + } + spin_unlock_irqrestore(&zone->lock, flags); + } + return NULL; +} +#endif /* CONFIG_CONTIG_ALLOC */ + +void free_contig_range(unsigned long pfn, unsigned long nr_pages) +{ + unsigned long count = 0; + struct folio *folio = pfn_folio(pfn); + + if (folio_test_large(folio)) { + int expected = folio_nr_pages(folio); + + if (nr_pages == expected) + folio_put(folio); + else + WARN(true, "PFN %lu: nr_pages %lu != expected %d\n", + pfn, nr_pages, expected); + return; + } for (; nr_pages--; pfn++) { struct page *page = pfn_to_page(pfn); @@ -8258,73 +7196,73 @@ void free_contig_range(unsigned long pfn, unsigned nr_pages) count += page_count(page) != 1; __free_page(page); } - WARN(count != 0, "%d pages are still in use!\n", count); + WARN(count != 0, "%lu pages are still in use!\n", count); } -#endif +EXPORT_SYMBOL(free_contig_range); -#ifdef CONFIG_MEMORY_HOTPLUG /* - * The zone indicated has a new number of managed_pages; batch sizes and percpu - * page high values need to be recalulated. + * Effectively disable pcplists for the zone by setting the high limit to 0 + * and draining all cpus. A concurrent page freeing on another CPU that's about + * to put the page on pcplist will either finish before the drain and the page + * will be drained, or observe the new high limit and skip the pcplist. + * + * Must be paired with a call to zone_pcp_enable(). */ -void __meminit zone_pcp_update(struct zone *zone) +void zone_pcp_disable(struct zone *zone) { - unsigned cpu; mutex_lock(&pcp_batch_high_lock); - for_each_possible_cpu(cpu) - pageset_set_high_and_batch(zone, - per_cpu_ptr(zone->pageset, cpu)); + __zone_set_pageset_high_and_batch(zone, 0, 0, 1); + __drain_all_pages(zone, true); +} + +void zone_pcp_enable(struct zone *zone) +{ + __zone_set_pageset_high_and_batch(zone, zone->pageset_high_min, + zone->pageset_high_max, zone->pageset_batch); mutex_unlock(&pcp_batch_high_lock); } -#endif void zone_pcp_reset(struct zone *zone) { - unsigned long flags; int cpu; - struct per_cpu_pageset *pset; + struct per_cpu_zonestat *pzstats; - /* avoid races with drain_pages() */ - local_irq_save(flags); - if (zone->pageset != &boot_pageset) { + if (zone->per_cpu_pageset != &boot_pageset) { for_each_online_cpu(cpu) { - pset = per_cpu_ptr(zone->pageset, cpu); - drain_zonestat(zone, pset); + pzstats = per_cpu_ptr(zone->per_cpu_zonestats, cpu); + drain_zonestat(zone, pzstats); + } + free_percpu(zone->per_cpu_pageset); + zone->per_cpu_pageset = &boot_pageset; + if (zone->per_cpu_zonestats != &boot_zonestats) { + free_percpu(zone->per_cpu_zonestats); + zone->per_cpu_zonestats = &boot_zonestats; } - free_percpu(zone->pageset); - zone->pageset = &boot_pageset; } - local_irq_restore(flags); } #ifdef CONFIG_MEMORY_HOTREMOVE /* - * All pages in the range must be in a single zone and isolated - * before calling this. + * All pages in the range must be in a single zone, must not contain holes, + * must span full sections, and must be isolated before calling this function. + * + * Returns the number of managed (non-PageOffline()) pages in the range: the + * number of pages for which memory offlining code must adjust managed page + * counters using adjust_managed_page_count(). */ -void -__offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn) +unsigned long __offline_isolated_pages(unsigned long start_pfn, + unsigned long end_pfn) { + unsigned long already_offline = 0, flags; + unsigned long pfn = start_pfn; struct page *page; struct zone *zone; - unsigned int order, i; - unsigned long pfn; - unsigned long flags; - /* find the first valid pfn */ - for (pfn = start_pfn; pfn < end_pfn; pfn++) - if (pfn_valid(pfn)) - break; - if (pfn == end_pfn) - return; + unsigned int order; + offline_mem_sections(pfn, end_pfn); zone = page_zone(pfn_to_page(pfn)); spin_lock_irqsave(&zone->lock, flags); - pfn = start_pfn; while (pfn < end_pfn) { - if (!pfn_valid(pfn)) { - pfn++; - continue; - } page = pfn_to_page(pfn); /* * The HWPoisoned page may be not in buddy system, and @@ -8332,73 +7270,415 @@ __offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn) */ if (unlikely(!PageBuddy(page) && PageHWPoison(page))) { pfn++; - SetPageReserved(page); + continue; + } + /* + * At this point all remaining PageOffline() pages have a + * reference count of 0 and can simply be skipped. + */ + if (PageOffline(page)) { + BUG_ON(page_count(page)); + BUG_ON(PageBuddy(page)); + already_offline++; + pfn++; continue; } BUG_ON(page_count(page)); BUG_ON(!PageBuddy(page)); - order = page_order(page); -#ifdef CONFIG_DEBUG_VM - pr_info("remove from free list %lx %d %lx\n", - pfn, 1 << order, end_pfn); -#endif - list_del(&page->lru); - rmv_page_order(page); - zone->free_area[order].nr_free--; - for (i = 0; i < (1 << order); i++) - SetPageReserved((page+i)); + VM_WARN_ON(get_pageblock_migratetype(page) != MIGRATE_ISOLATE); + order = buddy_order(page); + del_page_from_free_list(page, zone, order, MIGRATE_ISOLATE); pfn += (1 << order); } spin_unlock_irqrestore(&zone->lock, flags); + + return end_pfn - start_pfn - already_offline; } #endif -bool is_free_buddy_page(struct page *page) +/* + * This function returns a stable result only if called under zone lock. + */ +bool is_free_buddy_page(const struct page *page) { - struct zone *zone = page_zone(page); unsigned long pfn = page_to_pfn(page); - unsigned long flags; unsigned int order; - spin_lock_irqsave(&zone->lock, flags); - for (order = 0; order < MAX_ORDER; order++) { - struct page *page_head = page - (pfn & ((1 << order) - 1)); + for (order = 0; order < NR_PAGE_ORDERS; order++) { + const struct page *head = page - (pfn & ((1 << order) - 1)); - if (PageBuddy(page_head) && page_order(page_head) >= order) + if (PageBuddy(head) && + buddy_order_unsafe(head) >= order) break; } - spin_unlock_irqrestore(&zone->lock, flags); - return order < MAX_ORDER; + return order <= MAX_PAGE_ORDER; } +EXPORT_SYMBOL(is_free_buddy_page); #ifdef CONFIG_MEMORY_FAILURE +static inline void add_to_free_list(struct page *page, struct zone *zone, + unsigned int order, int migratetype, + bool tail) +{ + __add_to_free_list(page, zone, order, migratetype, tail); + account_freepages(zone, 1 << order, migratetype); +} + /* - * Set PG_hwpoison flag if a given page is confirmed to be a free page. This - * test is performed under the zone lock to prevent a race against page - * allocation. + * Break down a higher-order page in sub-pages, and keep our target out of + * buddy allocator. */ -bool set_hwpoison_free_buddy_page(struct page *page) +static void break_down_buddy_pages(struct zone *zone, struct page *page, + struct page *target, int low, int high, + int migratetype) +{ + unsigned long size = 1 << high; + struct page *current_buddy; + + while (high > low) { + high--; + size >>= 1; + + if (target >= &page[size]) { + current_buddy = page; + page = page + size; + } else { + current_buddy = page + size; + } + + if (set_page_guard(zone, current_buddy, high)) + continue; + + add_to_free_list(current_buddy, zone, high, migratetype, false); + set_buddy_order(current_buddy, high); + } +} + +/* + * Take a page that will be marked as poisoned off the buddy allocator. + */ +bool take_page_off_buddy(struct page *page) { struct zone *zone = page_zone(page); unsigned long pfn = page_to_pfn(page); unsigned long flags; unsigned int order; - bool hwpoisoned = false; + bool ret = false; spin_lock_irqsave(&zone->lock, flags); - for (order = 0; order < MAX_ORDER; order++) { + for (order = 0; order < NR_PAGE_ORDERS; order++) { struct page *page_head = page - (pfn & ((1 << order) - 1)); - - if (PageBuddy(page_head) && page_order(page_head) >= order) { - if (!TestSetPageHWPoison(page)) - hwpoisoned = true; + int page_order = buddy_order(page_head); + + if (PageBuddy(page_head) && page_order >= order) { + unsigned long pfn_head = page_to_pfn(page_head); + int migratetype = get_pfnblock_migratetype(page_head, + pfn_head); + + del_page_from_free_list(page_head, zone, page_order, + migratetype); + break_down_buddy_pages(zone, page_head, page, 0, + page_order, migratetype); + SetPageHWPoisonTakenOff(page); + ret = true; + break; + } + if (page_count(page_head) > 0) break; + } + spin_unlock_irqrestore(&zone->lock, flags); + return ret; +} + +/* + * Cancel takeoff done by take_page_off_buddy(). + */ +bool put_page_back_buddy(struct page *page) +{ + struct zone *zone = page_zone(page); + unsigned long flags; + bool ret = false; + + spin_lock_irqsave(&zone->lock, flags); + if (put_page_testzero(page)) { + unsigned long pfn = page_to_pfn(page); + int migratetype = get_pfnblock_migratetype(page, pfn); + + ClearPageHWPoisonTakenOff(page); + __free_one_page(page, pfn, zone, 0, migratetype, FPI_NONE); + if (TestClearPageHWPoison(page)) { + ret = true; } } spin_unlock_irqrestore(&zone->lock, flags); - return hwpoisoned; + return ret; } #endif + +#ifdef CONFIG_ZONE_DMA +bool has_managed_dma(void) +{ + struct pglist_data *pgdat; + + for_each_online_pgdat(pgdat) { + struct zone *zone = &pgdat->node_zones[ZONE_DMA]; + + if (managed_zone(zone)) + return true; + } + return false; +} +#endif /* CONFIG_ZONE_DMA */ + +#ifdef CONFIG_UNACCEPTED_MEMORY + +static bool lazy_accept = true; + +static int __init accept_memory_parse(char *p) +{ + if (!strcmp(p, "lazy")) { + lazy_accept = true; + return 0; + } else if (!strcmp(p, "eager")) { + lazy_accept = false; + return 0; + } else { + return -EINVAL; + } +} +early_param("accept_memory", accept_memory_parse); + +static bool page_contains_unaccepted(struct page *page, unsigned int order) +{ + phys_addr_t start = page_to_phys(page); + + return range_contains_unaccepted_memory(start, PAGE_SIZE << order); +} + +static void __accept_page(struct zone *zone, unsigned long *flags, + struct page *page) +{ + list_del(&page->lru); + account_freepages(zone, -MAX_ORDER_NR_PAGES, MIGRATE_MOVABLE); + __mod_zone_page_state(zone, NR_UNACCEPTED, -MAX_ORDER_NR_PAGES); + __ClearPageUnaccepted(page); + spin_unlock_irqrestore(&zone->lock, *flags); + + accept_memory(page_to_phys(page), PAGE_SIZE << MAX_PAGE_ORDER); + + __free_pages_ok(page, MAX_PAGE_ORDER, FPI_TO_TAIL); +} + +void accept_page(struct page *page) +{ + struct zone *zone = page_zone(page); + unsigned long flags; + + spin_lock_irqsave(&zone->lock, flags); + if (!PageUnaccepted(page)) { + spin_unlock_irqrestore(&zone->lock, flags); + return; + } + + /* Unlocks zone->lock */ + __accept_page(zone, &flags, page); +} + +static bool try_to_accept_memory_one(struct zone *zone) +{ + unsigned long flags; + struct page *page; + + spin_lock_irqsave(&zone->lock, flags); + page = list_first_entry_or_null(&zone->unaccepted_pages, + struct page, lru); + if (!page) { + spin_unlock_irqrestore(&zone->lock, flags); + return false; + } + + /* Unlocks zone->lock */ + __accept_page(zone, &flags, page); + + return true; +} + +static bool cond_accept_memory(struct zone *zone, unsigned int order, + int alloc_flags) +{ + long to_accept, wmark; + bool ret = false; + + if (list_empty(&zone->unaccepted_pages)) + return false; + + /* Bailout, since try_to_accept_memory_one() needs to take a lock */ + if (alloc_flags & ALLOC_TRYLOCK) + return false; + + wmark = promo_wmark_pages(zone); + + /* + * Watermarks have not been initialized yet. + * + * Accepting one MAX_ORDER page to ensure progress. + */ + if (!wmark) + return try_to_accept_memory_one(zone); + + /* How much to accept to get to promo watermark? */ + to_accept = wmark - + (zone_page_state(zone, NR_FREE_PAGES) - + __zone_watermark_unusable_free(zone, order, 0) - + zone_page_state(zone, NR_UNACCEPTED)); + + while (to_accept > 0) { + if (!try_to_accept_memory_one(zone)) + break; + ret = true; + to_accept -= MAX_ORDER_NR_PAGES; + } + + return ret; +} + +static bool __free_unaccepted(struct page *page) +{ + struct zone *zone = page_zone(page); + unsigned long flags; + + if (!lazy_accept) + return false; + + spin_lock_irqsave(&zone->lock, flags); + list_add_tail(&page->lru, &zone->unaccepted_pages); + account_freepages(zone, MAX_ORDER_NR_PAGES, MIGRATE_MOVABLE); + __mod_zone_page_state(zone, NR_UNACCEPTED, MAX_ORDER_NR_PAGES); + __SetPageUnaccepted(page); + spin_unlock_irqrestore(&zone->lock, flags); + + return true; +} + +#else + +static bool page_contains_unaccepted(struct page *page, unsigned int order) +{ + return false; +} + +static bool cond_accept_memory(struct zone *zone, unsigned int order, + int alloc_flags) +{ + return false; +} + +static bool __free_unaccepted(struct page *page) +{ + BUILD_BUG(); + return false; +} + +#endif /* CONFIG_UNACCEPTED_MEMORY */ + +struct page *alloc_frozen_pages_nolock_noprof(gfp_t gfp_flags, int nid, unsigned int order) +{ + /* + * Do not specify __GFP_DIRECT_RECLAIM, since direct claim is not allowed. + * Do not specify __GFP_KSWAPD_RECLAIM either, since wake up of kswapd + * is not safe in arbitrary context. + * + * These two are the conditions for gfpflags_allow_spinning() being true. + * + * Specify __GFP_NOWARN since failing alloc_pages_nolock() is not a reason + * to warn. Also warn would trigger printk() which is unsafe from + * various contexts. We cannot use printk_deferred_enter() to mitigate, + * since the running context is unknown. + * + * Specify __GFP_ZERO to make sure that call to kmsan_alloc_page() below + * is safe in any context. Also zeroing the page is mandatory for + * BPF use cases. + * + * Though __GFP_NOMEMALLOC is not checked in the code path below, + * specify it here to highlight that alloc_pages_nolock() + * doesn't want to deplete reserves. + */ + gfp_t alloc_gfp = __GFP_NOWARN | __GFP_ZERO | __GFP_NOMEMALLOC | __GFP_COMP + | gfp_flags; + unsigned int alloc_flags = ALLOC_TRYLOCK; + struct alloc_context ac = { }; + struct page *page; + + VM_WARN_ON_ONCE(gfp_flags & ~__GFP_ACCOUNT); + /* + * In PREEMPT_RT spin_trylock() will call raw_spin_lock() which is + * unsafe in NMI. If spin_trylock() is called from hard IRQ the current + * task may be waiting for one rt_spin_lock, but rt_spin_trylock() will + * mark the task as the owner of another rt_spin_lock which will + * confuse PI logic, so return immediately if called form hard IRQ or + * NMI. + * + * Note, irqs_disabled() case is ok. This function can be called + * from raw_spin_lock_irqsave region. + */ + if (IS_ENABLED(CONFIG_PREEMPT_RT) && (in_nmi() || in_hardirq())) + return NULL; + if (!pcp_allowed_order(order)) + return NULL; + + /* Bailout, since _deferred_grow_zone() needs to take a lock */ + if (deferred_pages_enabled()) + return NULL; + + if (nid == NUMA_NO_NODE) + nid = numa_node_id(); + + prepare_alloc_pages(alloc_gfp, order, nid, NULL, &ac, + &alloc_gfp, &alloc_flags); + + /* + * Best effort allocation from percpu free list. + * If it's empty attempt to spin_trylock zone->lock. + */ + page = get_page_from_freelist(alloc_gfp, order, alloc_flags, &ac); + + /* Unlike regular alloc_pages() there is no __alloc_pages_slowpath(). */ + + if (memcg_kmem_online() && page && (gfp_flags & __GFP_ACCOUNT) && + unlikely(__memcg_kmem_charge_page(page, alloc_gfp, order) != 0)) { + __free_frozen_pages(page, order, FPI_TRYLOCK); + page = NULL; + } + trace_mm_page_alloc(page, order, alloc_gfp, ac.migratetype); + kmsan_alloc_page(page, order, alloc_gfp); + return page; +} +/** + * alloc_pages_nolock - opportunistic reentrant allocation from any context + * @gfp_flags: GFP flags. Only __GFP_ACCOUNT allowed. + * @nid: node to allocate from + * @order: allocation order size + * + * Allocates pages of a given order from the given node. This is safe to + * call from any context (from atomic, NMI, and also reentrant + * allocator -> tracepoint -> alloc_pages_nolock_noprof). + * Allocation is best effort and to be expected to fail easily so nobody should + * rely on the success. Failures are not reported via warn_alloc(). + * See always fail conditions below. + * + * Return: allocated page or NULL on failure. NULL does not mean EBUSY or EAGAIN. + * It means ENOMEM. There is no reason to call it again and expect !NULL. + */ +struct page *alloc_pages_nolock_noprof(gfp_t gfp_flags, int nid, unsigned int order) +{ + struct page *page; + + page = alloc_frozen_pages_nolock_noprof(gfp_flags, nid, order); + if (page) + set_page_refcounted(page); + return page; +} +EXPORT_SYMBOL_GPL(alloc_pages_nolock_noprof); |