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-rw-r--r--mm/page_alloc.c294
1 files changed, 202 insertions, 92 deletions
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index c3edb624fccf..327516b7aee9 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -61,10 +61,14 @@
#include <linux/hugetlb.h>
#include <linux/sched/rt.h>
+#include <asm/sections.h>
#include <asm/tlbflush.h>
#include <asm/div64.h>
#include "internal.h"
+/* prevent >1 _updater_ of zone percpu pageset ->high and ->batch fields */
+static DEFINE_MUTEX(pcp_batch_high_lock);
+
#ifdef CONFIG_USE_PERCPU_NUMA_NODE_ID
DEFINE_PER_CPU(int, numa_node);
EXPORT_PER_CPU_SYMBOL(numa_node);
@@ -100,6 +104,9 @@ nodemask_t node_states[NR_NODE_STATES] __read_mostly = {
};
EXPORT_SYMBOL(node_states);
+/* Protect totalram_pages and zone->managed_pages */
+static DEFINE_SPINLOCK(managed_page_count_lock);
+
unsigned long totalram_pages __read_mostly;
unsigned long totalreserve_pages __read_mostly;
/*
@@ -739,14 +746,7 @@ static void __free_pages_ok(struct page *page, unsigned int order)
local_irq_restore(flags);
}
-/*
- * Read access to zone->managed_pages is safe because it's unsigned long,
- * but we still need to serialize writers. Currently all callers of
- * __free_pages_bootmem() except put_page_bootmem() should only be used
- * at boot time. So for shorter boot time, we shift the burden to
- * put_page_bootmem() to serialize writers.
- */
-void __meminit __free_pages_bootmem(struct page *page, unsigned int order)
+void __init __free_pages_bootmem(struct page *page, unsigned int order)
{
unsigned int nr_pages = 1 << order;
unsigned int loop;
@@ -781,11 +781,7 @@ void __init init_cma_reserved_pageblock(struct page *page)
set_page_refcounted(page);
set_pageblock_migratetype(page, MIGRATE_CMA);
__free_pages(page, pageblock_order);
- totalram_pages += pageblock_nr_pages;
-#ifdef CONFIG_HIGHMEM
- if (PageHighMem(page))
- totalhigh_pages += pageblock_nr_pages;
-#endif
+ adjust_managed_page_count(page, pageblock_nr_pages);
}
#endif
@@ -1179,10 +1175,12 @@ void drain_zone_pages(struct zone *zone, struct per_cpu_pages *pcp)
{
unsigned long flags;
int to_drain;
+ unsigned long batch;
local_irq_save(flags);
- if (pcp->count >= pcp->batch)
- to_drain = pcp->batch;
+ batch = ACCESS_ONCE(pcp->batch);
+ if (pcp->count >= batch)
+ to_drain = batch;
else
to_drain = pcp->count;
if (to_drain > 0) {
@@ -1350,8 +1348,9 @@ void free_hot_cold_page(struct page *page, int cold)
list_add(&page->lru, &pcp->lists[migratetype]);
pcp->count++;
if (pcp->count >= pcp->high) {
- free_pcppages_bulk(zone, pcp->batch, pcp);
- pcp->count -= pcp->batch;
+ unsigned long batch = ACCESS_ONCE(pcp->batch);
+ free_pcppages_bulk(zone, batch, pcp);
+ pcp->count -= batch;
}
out:
@@ -2839,7 +2838,7 @@ EXPORT_SYMBOL(free_pages_exact);
* nr_free_zone_pages() counts the number of counts 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:
- * present_pages - high_pages
+ * managed_pages - high_pages
*/
static unsigned long nr_free_zone_pages(int offset)
{
@@ -2906,9 +2905,13 @@ 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;
pg_data_t *pgdat = NODE_DATA(nid);
- val->totalram = pgdat->node_present_pages;
+ for (zone_type = 0; zone_type < MAX_NR_ZONES; zone_type++)
+ managed_pages += pgdat->node_zones[zone_type].managed_pages;
+ val->totalram = managed_pages;
val->freeram = node_page_state(nid, NR_FREE_PAGES);
#ifdef CONFIG_HIGHMEM
val->totalhigh = pgdat->node_zones[ZONE_HIGHMEM].managed_pages;
@@ -3250,18 +3253,25 @@ int numa_zonelist_order_handler(ctl_table *table, int write,
static DEFINE_MUTEX(zl_order_mutex);
mutex_lock(&zl_order_mutex);
- if (write)
- strcpy(saved_string, (char*)table->data);
+ if (write) {
+ if (strlen((char *)table->data) >= NUMA_ZONELIST_ORDER_LEN) {
+ ret = -EINVAL;
+ goto out;
+ }
+ strcpy(saved_string, (char *)table->data);
+ }
ret = proc_dostring(table, write, buffer, length, ppos);
if (ret)
goto out;
if (write) {
int oldval = user_zonelist_order;
- if (__parse_numa_zonelist_order((char*)table->data)) {
+
+ ret = __parse_numa_zonelist_order((char *)table->data);
+ if (ret) {
/*
* bogus value. restore saved string
*/
- strncpy((char*)table->data, saved_string,
+ strncpy((char *)table->data, saved_string,
NUMA_ZONELIST_ORDER_LEN);
user_zonelist_order = oldval;
} else if (oldval != user_zonelist_order) {
@@ -3425,8 +3435,8 @@ static int default_zonelist_order(void)
z = &NODE_DATA(nid)->node_zones[zone_type];
if (populated_zone(z)) {
if (zone_type < ZONE_NORMAL)
- low_kmem_size += z->present_pages;
- total_size += z->present_pages;
+ low_kmem_size += z->managed_pages;
+ total_size += z->managed_pages;
} else if (zone_type == ZONE_NORMAL) {
/*
* If any node has only lowmem, then node order
@@ -3705,12 +3715,12 @@ void __ref build_all_zonelists(pg_data_t *pgdat, struct zone *zone)
mminit_verify_zonelist();
cpuset_init_current_mems_allowed();
} else {
- /* we have to stop all cpus to guarantee there is no user
- of zonelist */
#ifdef CONFIG_MEMORY_HOTPLUG
if (zone)
setup_zone_pageset(zone);
#endif
+ /* we have to stop all cpus to guarantee there is no user
+ of zonelist */
stop_machine(__build_all_zonelists, pgdat, NULL);
/* cpuset refresh routine should be here */
}
@@ -4032,7 +4042,40 @@ static int __meminit zone_batchsize(struct zone *zone)
#endif
}
-static void setup_pageset(struct per_cpu_pageset *p, unsigned long batch)
+/*
+ * 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;
@@ -4041,45 +4084,55 @@ static void setup_pageset(struct per_cpu_pageset *p, unsigned long batch)
pcp = &p->pcp;
pcp->count = 0;
- pcp->high = 6 * batch;
- pcp->batch = max(1UL, 1 * batch);
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);
+}
+
/*
- * setup_pagelist_highmark() sets the high water mark for hot per_cpu_pagelist
+ * pageset_set_high() sets the high water mark for hot per_cpu_pagelist
* to the value high for the pageset p.
*/
-
-static void setup_pagelist_highmark(struct per_cpu_pageset *p,
+static void pageset_set_high(struct per_cpu_pageset *p,
unsigned long high)
{
- struct per_cpu_pages *pcp;
+ unsigned long batch = max(1UL, high / 4);
+ if ((high / 4) > (PAGE_SHIFT * 8))
+ batch = PAGE_SHIFT * 8;
- pcp = &p->pcp;
- pcp->high = high;
- pcp->batch = max(1UL, high/4);
- if ((high/4) > (PAGE_SHIFT * 8))
- pcp->batch = PAGE_SHIFT * 8;
+ pageset_update(&p->pcp, high, batch);
}
-static void __meminit setup_zone_pageset(struct zone *zone)
+static void __meminit pageset_set_high_and_batch(struct zone *zone,
+ struct per_cpu_pageset *pcp)
{
- int cpu;
-
- zone->pageset = alloc_percpu(struct per_cpu_pageset);
+ if (percpu_pagelist_fraction)
+ pageset_set_high(pcp,
+ (zone->managed_pages /
+ percpu_pagelist_fraction));
+ else
+ pageset_set_batch(pcp, zone_batchsize(zone));
+}
- for_each_possible_cpu(cpu) {
- struct per_cpu_pageset *pcp = per_cpu_ptr(zone->pageset, cpu);
+static void __meminit zone_pageset_init(struct zone *zone, int cpu)
+{
+ struct per_cpu_pageset *pcp = per_cpu_ptr(zone->pageset, cpu);
- setup_pageset(pcp, zone_batchsize(zone));
+ pageset_init(pcp);
+ pageset_set_high_and_batch(zone, pcp);
+}
- if (percpu_pagelist_fraction)
- setup_pagelist_highmark(pcp,
- (zone->managed_pages /
- percpu_pagelist_fraction));
- }
+static 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);
}
/*
@@ -5150,35 +5203,101 @@ early_param("movablecore", cmdline_parse_movablecore);
#endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
-unsigned long free_reserved_area(unsigned long start, unsigned long end,
- int poison, char *s)
+void adjust_managed_page_count(struct page *page, long count)
+{
+ spin_lock(&managed_page_count_lock);
+ page_zone(page)->managed_pages += count;
+ totalram_pages += count;
+#ifdef CONFIG_HIGHMEM
+ if (PageHighMem(page))
+ totalhigh_pages += count;
+#endif
+ spin_unlock(&managed_page_count_lock);
+}
+EXPORT_SYMBOL(adjust_managed_page_count);
+
+unsigned long free_reserved_area(void *start, void *end, int poison, char *s)
{
- unsigned long pages, pos;
+ void *pos;
+ unsigned long pages = 0;
- pos = start = PAGE_ALIGN(start);
- end &= PAGE_MASK;
- for (pages = 0; pos < end; pos += PAGE_SIZE, pages++) {
- if (poison)
- memset((void *)pos, poison, PAGE_SIZE);
- free_reserved_page(virt_to_page((void *)pos));
+ start = (void *)PAGE_ALIGN((unsigned long)start);
+ end = (void *)((unsigned long)end & PAGE_MASK);
+ for (pos = start; pos < end; pos += PAGE_SIZE, pages++) {
+ if ((unsigned int)poison <= 0xFF)
+ memset(pos, poison, PAGE_SIZE);
+ free_reserved_page(virt_to_page(pos));
}
if (pages && s)
- pr_info("Freeing %s memory: %ldK (%lx - %lx)\n",
+ pr_info("Freeing %s memory: %ldK (%p - %p)\n",
s, pages << (PAGE_SHIFT - 10), start, end);
return pages;
}
+EXPORT_SYMBOL(free_reserved_area);
#ifdef CONFIG_HIGHMEM
void free_highmem_page(struct page *page)
{
__free_reserved_page(page);
totalram_pages++;
+ page_zone(page)->managed_pages++;
totalhigh_pages++;
}
#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) \
+ if (start <= pos && pos < end && size > adj) \
+ size -= adj;
+
+ 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
+
+ printk("Memory: %luK/%luK available "
+ "(%luK kernel code, %luK rwdata, %luK rodata, "
+ "%luK init, %luK bss, %luK 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) << (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
@@ -5540,7 +5659,6 @@ int lowmem_reserve_ratio_sysctl_handler(ctl_table *table, int write,
* 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(ctl_table *table, int write,
void __user *buffer, size_t *length, loff_t *ppos)
{
@@ -5551,14 +5669,16 @@ int percpu_pagelist_fraction_sysctl_handler(ctl_table *table, int write,
ret = proc_dointvec_minmax(table, write, buffer, length, ppos);
if (!write || (ret < 0))
return ret;
+
+ mutex_lock(&pcp_batch_high_lock);
for_each_populated_zone(zone) {
- for_each_possible_cpu(cpu) {
- unsigned long high;
- high = zone->managed_pages / percpu_pagelist_fraction;
- setup_pagelist_highmark(
- per_cpu_ptr(zone->pageset, cpu), high);
- }
+ unsigned long high;
+ high = zone->managed_pages / percpu_pagelist_fraction;
+ for_each_possible_cpu(cpu)
+ pageset_set_high(per_cpu_ptr(zone->pageset, cpu),
+ high);
}
+ mutex_unlock(&pcp_batch_high_lock);
return 0;
}
@@ -6047,32 +6167,18 @@ void free_contig_range(unsigned long pfn, unsigned nr_pages)
#endif
#ifdef CONFIG_MEMORY_HOTPLUG
-static int __meminit __zone_pcp_update(void *data)
-{
- struct zone *zone = data;
- int cpu;
- unsigned long batch = zone_batchsize(zone), flags;
-
- for_each_possible_cpu(cpu) {
- struct per_cpu_pageset *pset;
- struct per_cpu_pages *pcp;
-
- pset = per_cpu_ptr(zone->pageset, cpu);
- pcp = &pset->pcp;
-
- local_irq_save(flags);
- if (pcp->count > 0)
- free_pcppages_bulk(zone, pcp->count, pcp);
- drain_zonestat(zone, pset);
- setup_pageset(pset, batch);
- local_irq_restore(flags);
- }
- return 0;
-}
-
+/*
+ * The zone indicated has a new number of managed_pages; batch sizes and percpu
+ * page high values need to be recalulated.
+ */
void __meminit zone_pcp_update(struct zone *zone)
{
- stop_machine(__zone_pcp_update, zone, NULL);
+ 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));
+ mutex_unlock(&pcp_batch_high_lock);
}
#endif
@@ -6142,6 +6248,10 @@ __offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn)
list_del(&page->lru);
rmv_page_order(page);
zone->free_area[order].nr_free--;
+#ifdef CONFIG_HIGHMEM
+ if (PageHighMem(page))
+ totalhigh_pages -= 1 << order;
+#endif
for (i = 0; i < (1 << order); i++)
SetPageReserved((page+i));
pfn += (1 << order);