1 files changed, 197 insertions, 125 deletions

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index c21b33668133..9f9623d690d6 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -59,7 +59,6 @@
 #include <linux/prefetch.h>
 #include <linux/mm_inline.h>
 #include <linux/migrate.h>
-#include <linux/page_ext.h>
 #include <linux/hugetlb.h>
 #include <linux/sched/rt.h>
 #include <linux/page_owner.h>
@@ -92,6 +91,10 @@ EXPORT_PER_CPU_SYMBOL(_numa_mem_);
 int _node_numa_mem_[MAX_NUMNODES];
 #endif
 
+/* work_structs for global per-cpu drains */
+DEFINE_MUTEX(pcpu_drain_mutex);
+DEFINE_PER_CPU(struct work_struct, pcpu_drain);
+
 #ifdef CONFIG_GCC_PLUGIN_LATENT_ENTROPY
 volatile unsigned long latent_entropy __latent_entropy;
 EXPORT_SYMBOL(latent_entropy);
@@ -1085,10 +1088,10 @@ static void free_pcppages_bulk(struct zone *zone, int count,
 {
 	int migratetype = 0;
 	int batch_free = 0;
-	unsigned long nr_scanned;
+	unsigned long nr_scanned, flags;
 	bool isolated_pageblocks;
 
-	spin_lock(&zone->lock);
+	spin_lock_irqsave(&zone->lock, flags);
 	isolated_pageblocks = has_isolate_pageblock(zone);
 	nr_scanned = node_page_state(zone->zone_pgdat, NR_PAGES_SCANNED);
 	if (nr_scanned)
@@ -1137,7 +1140,7 @@ static void free_pcppages_bulk(struct zone *zone, int count,
 			trace_mm_page_pcpu_drain(page, 0, mt);
 		} while (--count && --batch_free && !list_empty(list));
 	}
-	spin_unlock(&zone->lock);
+	spin_unlock_irqrestore(&zone->lock, flags);
 }
 
 static void free_one_page(struct zone *zone,
@@ -1145,8 +1148,9 @@ static void free_one_page(struct zone *zone,
 				unsigned int order,
 				int migratetype)
 {
-	unsigned long nr_scanned;
-	spin_lock(&zone->lock);
+	unsigned long nr_scanned, flags;
+	spin_lock_irqsave(&zone->lock, flags);
+	__count_vm_events(PGFREE, 1 << order);
 	nr_scanned = node_page_state(zone->zone_pgdat, NR_PAGES_SCANNED);
 	if (nr_scanned)
 		__mod_node_page_state(zone->zone_pgdat, NR_PAGES_SCANNED, -nr_scanned);
@@ -1156,7 +1160,7 @@ static void free_one_page(struct zone *zone,
 		migratetype = get_pfnblock_migratetype(page, pfn);
 	}
 	__free_one_page(page, pfn, zone, order, migratetype);
-	spin_unlock(&zone->lock);
+	spin_unlock_irqrestore(&zone->lock, flags);
 }
 
 static void __meminit __init_single_page(struct page *page, unsigned long pfn,
@@ -1234,7 +1238,6 @@ void __meminit reserve_bootmem_region(phys_addr_t start, phys_addr_t end)
 
 static void __free_pages_ok(struct page *page, unsigned int order)
 {
-	unsigned long flags;
 	int migratetype;
 	unsigned long pfn = page_to_pfn(page);
 
@@ -1242,10 +1245,7 @@ static void __free_pages_ok(struct page *page, unsigned int order)
 		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);
 }
 
 static void __init __free_pages_boot_core(struct page *page, unsigned int order)
@@ -2217,8 +2217,9 @@ static int rmqueue_bulk(struct zone *zone, unsigned int order,
 			int migratetype, bool cold)
 {
 	int i, alloced = 0;
+	unsigned long flags;
 
-	spin_lock(&zone->lock);
+	spin_lock_irqsave(&zone->lock, flags);
 	for (i = 0; i < count; ++i) {
 		struct page *page = __rmqueue(zone, order, migratetype);
 		if (unlikely(page == NULL))
@@ -2254,7 +2255,7 @@ static int rmqueue_bulk(struct zone *zone, unsigned int order,
 	 * pages added to the pcp list.
 	 */
 	__mod_zone_page_state(zone, NR_FREE_PAGES, -(i << order));
-	spin_unlock(&zone->lock);
+	spin_unlock_irqrestore(&zone->lock, flags);
 	return alloced;
 }
 
@@ -2339,16 +2340,26 @@ void drain_local_pages(struct zone *zone)
 		drain_pages(cpu);
 }
 
+static void drain_local_pages_wq(struct work_struct *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(NULL);
+	preempt_enable();
+}
+
 /*
  * 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.
  *
- * Note that this code is protected against sending an IPI to an offline
- * CPU but does not guarantee sending an IPI to newly hotplugged CPUs:
- * on_each_cpu_mask() blocks hotplug and won't talk to offlined CPUs but
- * nothing keeps CPUs from showing up after we populated the cpumask and
- * before the call to on_each_cpu_mask().
+ * Note that this can be extremely slow as the draining happens in a workqueue.
  */
 void drain_all_pages(struct zone *zone)
 {
@@ -2360,6 +2371,21 @@ void drain_all_pages(struct zone *zone)
 	 */
 	static cpumask_t cpus_with_pcps;
 
+	/* Workqueues cannot recurse */
+	if (current->flags & PF_WQ_WORKER)
+		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.
+	 */
+	if (unlikely(!mutex_trylock(&pcpu_drain_mutex))) {
+		if (!zone)
+			return;
+		mutex_lock(&pcpu_drain_mutex);
+	}
+
 	/*
 	 * We don't care about racing with CPU hotplug event
 	 * as offline notification will cause the notified
@@ -2390,8 +2416,16 @@ void drain_all_pages(struct zone *zone)
 		else
 			cpumask_clear_cpu(cpu, &cpus_with_pcps);
 	}
-	on_each_cpu_mask(&cpus_with_pcps, (smp_call_func_t) drain_local_pages,
-								zone, 1);
+
+	for_each_cpu(cpu, &cpus_with_pcps) {
+		struct work_struct *work = per_cpu_ptr(&pcpu_drain, cpu);
+		INIT_WORK(work, drain_local_pages_wq);
+		schedule_work_on(cpu, work);
+	}
+	for_each_cpu(cpu, &cpus_with_pcps)
+		flush_work(per_cpu_ptr(&pcpu_drain, cpu));
+
+	mutex_unlock(&pcpu_drain_mutex);
 }
 
 #ifdef CONFIG_HIBERNATION
@@ -2442,17 +2476,20 @@ void free_hot_cold_page(struct page *page, bool cold)
 {
 	struct zone *zone = page_zone(page);
 	struct per_cpu_pages *pcp;
-	unsigned long flags;
 	unsigned long pfn = page_to_pfn(page);
 	int migratetype;
 
+	if (in_interrupt()) {
+		__free_pages_ok(page, 0);
+		return;
+	}
+
 	if (!free_pcp_prepare(page))
 		return;
 
 	migratetype = get_pfnblock_migratetype(page, pfn);
 	set_pcppage_migratetype(page, migratetype);
-	local_irq_save(flags);
-	__count_vm_event(PGFREE);
+	preempt_disable();
 
 	/*
 	 * We only track unmovable, reclaimable and movable on pcp lists.
@@ -2469,6 +2506,7 @@ void free_hot_cold_page(struct page *page, bool cold)
 		migratetype = MIGRATE_MOVABLE;
 	}
 
+	__count_vm_event(PGFREE);
 	pcp = &this_cpu_ptr(zone->pageset)->pcp;
 	if (!cold)
 		list_add(&page->lru, &pcp->lists[migratetype]);
@@ -2482,7 +2520,7 @@ void free_hot_cold_page(struct page *page, bool cold)
 	}
 
 out:
-	local_irq_restore(flags);
+	preempt_enable();
 }
 
 /*
@@ -2600,74 +2638,105 @@ static inline void zone_statistics(struct zone *preferred_zone, struct zone *z)
 #endif
 }
 
+/* Remove page from the per-cpu list, caller must protect the list */
+static struct page *__rmqueue_pcplist(struct zone *zone, int migratetype,
+			bool cold, struct per_cpu_pages *pcp,
+			struct list_head *list)
+{
+	struct page *page;
+
+	VM_BUG_ON(in_interrupt());
+
+	do {
+		if (list_empty(list)) {
+			pcp->count += rmqueue_bulk(zone, 0,
+					pcp->batch, list,
+					migratetype, cold);
+			if (unlikely(list_empty(list)))
+				return NULL;
+		}
+
+		if (cold)
+			page = list_last_entry(list, struct page, lru);
+		else
+			page = list_first_entry(list, struct page, lru);
+
+		list_del(&page->lru);
+		pcp->count--;
+	} while (check_new_pcp(page));
+
+	return page;
+}
+
+/* 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)
+{
+	struct per_cpu_pages *pcp;
+	struct list_head *list;
+	bool cold = ((gfp_flags & __GFP_COLD) != 0);
+	struct page *page;
+
+	preempt_disable();
+	pcp = &this_cpu_ptr(zone->pageset)->pcp;
+	list = &pcp->lists[migratetype];
+	page = __rmqueue_pcplist(zone,  migratetype, cold, pcp, list);
+	if (page) {
+		__count_zid_vm_events(PGALLOC, page_zonenum(page), 1 << order);
+		zone_statistics(preferred_zone, zone);
+	}
+	preempt_enable();
+	return page;
+}
+
 /*
  * Allocate a page from the given zone. Use pcplists for order-0 allocations.
  */
 static inline
-struct page *buffered_rmqueue(struct zone *preferred_zone,
+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;
-	bool cold = ((gfp_flags & __GFP_COLD) != 0);
 
-	if (likely(order == 0)) {
-		struct per_cpu_pages *pcp;
-		struct list_head *list;
-
-		local_irq_save(flags);
-		do {
-			pcp = &this_cpu_ptr(zone->pageset)->pcp;
-			list = &pcp->lists[migratetype];
-			if (list_empty(list)) {
-				pcp->count += rmqueue_bulk(zone, 0,
-						pcp->batch, list,
-						migratetype, cold);
-				if (unlikely(list_empty(list)))
-					goto failed;
-			}
-
-			if (cold)
-				page = list_last_entry(list, struct page, lru);
-			else
-				page = list_first_entry(list, struct page, lru);
-
-			list_del(&page->lru);
-			pcp->count--;
+	if (likely(order == 0) && !in_interrupt()) {
+		page = rmqueue_pcplist(preferred_zone, zone, order,
+				gfp_flags, migratetype);
+		goto out;
+	}
 
-		} while (check_new_pcp(page));
-	} else {
-		/*
-		 * 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);
+	/*
+	 * 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);
-		} while (page && check_new_pages(page, order));
-		spin_unlock(&zone->lock);
+	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)
-			goto failed;
-		__mod_zone_freepage_state(zone, -(1 << order),
-					  get_pcppage_migratetype(page));
-	}
+			page = __rmqueue(zone, order, migratetype);
+	} 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);
 
-	VM_BUG_ON_PAGE(bad_range(zone, page), page);
+out:
+	VM_BUG_ON_PAGE(page && bad_range(zone, page), page);
 	return page;
 
 failed:
@@ -2875,7 +2944,7 @@ bool zone_watermark_ok_safe(struct zone *z, unsigned int order,
 #ifdef CONFIG_NUMA
 static bool zone_allows_reclaim(struct zone *local_zone, struct zone *zone)
 {
-	return node_distance(zone_to_nid(local_zone), zone_to_nid(zone)) <
+	return node_distance(zone_to_nid(local_zone), zone_to_nid(zone)) <=
 				RECLAIM_DISTANCE;
 }
 #else	/* CONFIG_NUMA */
@@ -2972,7 +3041,7 @@ get_page_from_freelist(gfp_t gfp_mask, unsigned int order, int alloc_flags,
 		}
 
 try_this_zone:
-		page = buffered_rmqueue(ac->preferred_zoneref->zone, zone, order,
+		page = rmqueue(ac->preferred_zoneref->zone, zone, order,
 				gfp_mask, alloc_flags, ac->migratetype);
 		if (page) {
 			prep_new_page(page, order, gfp_mask, alloc_flags);
@@ -3825,76 +3894,76 @@ got_pg:
 	return page;
 }
 
-/*
- * This is the 'heart' of the zoned buddy allocator.
- */
-struct page *
-__alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order,
-			struct zonelist *zonelist, nodemask_t *nodemask)
+static inline bool prepare_alloc_pages(gfp_t gfp_mask, unsigned int order,
+		struct zonelist *zonelist, nodemask_t *nodemask,
+		struct alloc_context *ac, gfp_t *alloc_mask,
+		unsigned int *alloc_flags)
 {
-	struct page *page;
-	unsigned int alloc_flags = ALLOC_WMARK_LOW;
-	gfp_t alloc_mask = gfp_mask; /* The gfp_t that was actually used for allocation */
-	struct alloc_context ac = {
-		.high_zoneidx = gfp_zone(gfp_mask),
-		.zonelist = zonelist,
-		.nodemask = nodemask,
-		.migratetype = gfpflags_to_migratetype(gfp_mask),
-	};
+	ac->high_zoneidx = gfp_zone(gfp_mask);
+	ac->zonelist = zonelist;
+	ac->nodemask = nodemask;
+	ac->migratetype = gfpflags_to_migratetype(gfp_mask);
 
 	if (cpusets_enabled()) {
-		alloc_mask |= __GFP_HARDWALL;
-		alloc_flags |= ALLOC_CPUSET;
-		if (!ac.nodemask)
-			ac.nodemask = &cpuset_current_mems_allowed;
+		*alloc_mask |= __GFP_HARDWALL;
+		if (!ac->nodemask)
+			ac->nodemask = &cpuset_current_mems_allowed;
+		else
+			*alloc_flags |= ALLOC_CPUSET;
 	}
 
-	gfp_mask &= gfp_allowed_mask;
-
 	lockdep_trace_alloc(gfp_mask);
 
 	might_sleep_if(gfp_mask & __GFP_DIRECT_RECLAIM);
 
 	if (should_fail_alloc_page(gfp_mask, order))
-		return NULL;
+		return false;
 
-	/*
-	 * Check the zones suitable for the gfp_mask contain at least one
-	 * valid zone. It's possible to have an empty zonelist as a result
-	 * of __GFP_THISNODE and a memoryless node
-	 */
-	if (unlikely(!zonelist->_zonerefs->zone))
-		return NULL;
+	if (IS_ENABLED(CONFIG_CMA) && ac->migratetype == MIGRATE_MOVABLE)
+		*alloc_flags |= ALLOC_CMA;
 
-	if (IS_ENABLED(CONFIG_CMA) && ac.migratetype == MIGRATE_MOVABLE)
-		alloc_flags |= ALLOC_CMA;
+	return true;
+}
 
+/* Determine whether to spread dirty pages and what the first usable zone */
+static inline void finalise_ac(gfp_t gfp_mask,
+		unsigned int order, struct alloc_context *ac)
+{
 	/* Dirty zone balancing only done in the fast path */
-	ac.spread_dirty_pages = (gfp_mask & __GFP_WRITE);
+	ac->spread_dirty_pages = (gfp_mask & __GFP_WRITE);
 
 	/*
 	 * The preferred zone is used for statistics but crucially it is
 	 * also used as the starting point for the zonelist iterator. It
 	 * may get reset for allocations that ignore memory policies.
 	 */
-	ac.preferred_zoneref = first_zones_zonelist(ac.zonelist,
-					ac.high_zoneidx, ac.nodemask);
-	if (!ac.preferred_zoneref->zone) {
-		page = NULL;
-		/*
-		 * This might be due to race with cpuset_current_mems_allowed
-		 * update, so make sure we retry with original nodemask in the
-		 * slow path.
-		 */
-		goto no_zone;
-	}
+	ac->preferred_zoneref = first_zones_zonelist(ac->zonelist,
+					ac->high_zoneidx, ac->nodemask);
+}
+
+/*
+ * This is the 'heart' of the zoned buddy allocator.
+ */
+struct page *
+__alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order,
+			struct zonelist *zonelist, nodemask_t *nodemask)
+{
+	struct page *page;
+	unsigned int alloc_flags = ALLOC_WMARK_LOW;
+	gfp_t alloc_mask = gfp_mask; /* The gfp_t that was actually used for allocation */
+	struct alloc_context ac = { };
+
+	gfp_mask &= gfp_allowed_mask;
+	if (!prepare_alloc_pages(gfp_mask, order, zonelist, nodemask, &ac, &alloc_mask, &alloc_flags))
+		return NULL;
+
+	finalise_ac(gfp_mask, order, &ac);
 
 	/* First allocation attempt */
 	page = get_page_from_freelist(alloc_mask, order, alloc_flags, &ac);
 	if (likely(page))
 		goto out;
 
-no_zone:
 	/*
 	 * Runtime PM, block IO and its error handling path can deadlock
 	 * because I/O on the device might not complete.
@@ -6420,8 +6489,6 @@ void __init free_area_init_nodes(unsigned long *max_zone_pfn)
 
 		start_pfn = end_pfn;
 	}
-	arch_zone_lowest_possible_pfn[ZONE_MOVABLE] = 0;
-	arch_zone_highest_possible_pfn[ZONE_MOVABLE] = 0;
 
 	/* Find the PFNs that ZONE_MOVABLE begins at in each node */
 	memset(zone_movable_pfn, 0, sizeof(zone_movable_pfn));
@@ -7157,8 +7224,9 @@ void *__init alloc_large_system_hash(const char *tablename,
  * 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. It means you can't
- * expect this function should be exact.
+ * 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,
 			 bool skip_hwpoisoned_pages)
@@ -7214,6 +7282,9 @@ bool has_unmovable_pages(struct zone *zone, struct page *page, int count,
 		if (skip_hwpoisoned_pages && PageHWPoison(page))
 			continue;
 
+		if (__PageMovable(page))
+			continue;
+
 		if (!PageLRU(page))
 			found++;
 		/*
@@ -7325,6 +7396,7 @@ static int __alloc_contig_migrate_range(struct compact_control *cc,
  *			#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
  *
  * The PFN range does not have to be pageblock or MAX_ORDER_NR_PAGES
  * aligned, however it's the caller's responsibility to guarantee that
@@ -7338,7 +7410,7 @@ static int __alloc_contig_migrate_range(struct compact_control *cc,
  * need to be freed with free_contig_range().
  */
 int alloc_contig_range(unsigned long start, unsigned long end,
-		       unsigned migratetype)
+		       unsigned migratetype, gfp_t gfp_mask)
 {
 	unsigned long outer_start, outer_end;
 	unsigned int order;
@@ -7350,7 +7422,7 @@ int alloc_contig_range(unsigned long start, unsigned long end,
 		.zone = page_zone(pfn_to_page(start)),
 		.mode = MIGRATE_SYNC,
 		.ignore_skip_hint = true,
-		.gfp_mask = GFP_KERNEL,
+		.gfp_mask = memalloc_noio_flags(gfp_mask),
 	};
 	INIT_LIST_HEAD(&cc.migratepages);