Merge branch 'akpm' (patches from Andrew)

Merge two mm fixes from Andrew Morton.

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  mm: prevent NR_ISOLATE_* stats from going negative
  Revert "mm, page_alloc: only use per-cpu allocator for irq-safe requests"

mm/migrate.c

@@ -184,9 +184,9 @@ void putback_movable_pages(struct list_head *l)
 			unlock_page(page);
 			put_page(page);
 		} else {
-			putback_lru_page(page);
 			dec_node_page_state(page, NR_ISOLATED_ANON +
 					page_is_file_cache(page));
+			putback_lru_page(page);
 		}
 	}
 }

mm/page_alloc.c

@@ -1090,10 +1090,10 @@ static void free_pcppages_bulk(struct zone *zone, int count,
 {
 	int migratetype = 0;
 	int batch_free = 0;
-	unsigned long nr_scanned, flags;
+	unsigned long nr_scanned;
 	bool isolated_pageblocks;
 
-	spin_lock_irqsave(&zone->lock, flags);
+	spin_lock(&zone->lock);
 	isolated_pageblocks = has_isolate_pageblock(zone);
 	nr_scanned = node_page_state(zone->zone_pgdat, NR_PAGES_SCANNED);
 	if (nr_scanned)
@@ -1142,7 +1142,7 @@ 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_irqrestore(&zone->lock, flags);
+	spin_unlock(&zone->lock);
 }
 
 static void free_one_page(struct zone *zone,
@@ -1150,9 +1150,8 @@ static void free_one_page(struct zone *zone,
 				unsigned int order,
 				int migratetype)
 {
-	unsigned long nr_scanned, flags;
+	unsigned long nr_scanned;
-	spin_lock_irqsave(&zone->lock, flags);
+	spin_lock(&zone->lock);
-	__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);
@@ -1162,7 +1161,7 @@ static void free_one_page(struct zone *zone,
 		migratetype = get_pfnblock_migratetype(page, pfn);
 	}
 	__free_one_page(page, pfn, zone, order, migratetype);
-	spin_unlock_irqrestore(&zone->lock, flags);
+	spin_unlock(&zone->lock);
 }
 
 static void __meminit __init_single_page(struct page *page, unsigned long pfn,
@@ -1240,6 +1239,7 @@ 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);
 
@@ -1247,7 +1247,10 @@ 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)
@@ -2219,9 +2222,8 @@ static int rmqueue_bulk(struct zone *zone, unsigned int order,
 			int migratetype, bool cold)
 {
 	int i, alloced = 0;
-	unsigned long flags;
 
-	spin_lock_irqsave(&zone->lock, flags);
+	spin_lock(&zone->lock);
 	for (i = 0; i < count; ++i) {
 		struct page *page = __rmqueue(zone, order, migratetype);
 		if (unlikely(page == NULL))
@@ -2257,7 +2259,7 @@ 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_irqrestore(&zone->lock, flags);
+	spin_unlock(&zone->lock);
 	return alloced;
 }
 
@@ -2485,20 +2487,17 @@ 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);
-	preempt_disable();
+	local_irq_save(flags);
+	__count_vm_event(PGFREE);
 
 	/*
 	 * We only track unmovable, reclaimable and movable on pcp lists.
@@ -2515,7 +2514,6 @@ 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]);
@@ -2529,7 +2527,7 @@ void free_hot_cold_page(struct page *page, bool cold)
 	}
 
 out:
-	preempt_enable();
+	local_irq_restore(flags);
 }
 
 /*
@@ -2654,8 +2652,6 @@ static struct page *__rmqueue_pcplist(struct zone *zone, int migratetype,
 {
 	struct page *page;
 
-	VM_BUG_ON(in_interrupt());
-
 	do {
 		if (list_empty(list)) {
 			pcp->count += rmqueue_bulk(zone, 0,
@@ -2686,8 +2682,9 @@ static struct page *rmqueue_pcplist(struct zone *preferred_zone,
 	struct list_head *list;
 	bool cold = ((gfp_flags & __GFP_COLD) != 0);
 	struct page *page;
+	unsigned long flags;
 
-	preempt_disable();
+	local_irq_save(flags);
 	pcp = &this_cpu_ptr(zone->pageset)->pcp;
 	list = &pcp->lists[migratetype];
 	page = __rmqueue_pcplist(zone,  migratetype, cold, pcp, list);
@@ -2695,7 +2692,7 @@ static struct page *rmqueue_pcplist(struct zone *preferred_zone,
 		__count_zid_vm_events(PGALLOC, page_zonenum(page), 1 << order);
 		zone_statistics(preferred_zone, zone);
 	}
-	preempt_enable();
+	local_irq_restore(flags);
 	return page;
 }
 
@@ -2711,7 +2708,7 @@ struct page *rmqueue(struct zone *preferred_zone,
 	unsigned long flags;
 	struct page *page;
 
-	if (likely(order == 0) && !in_interrupt()) {
+	if (likely(order == 0)) {
 		page = rmqueue_pcplist(preferred_zone, zone, order,
 				gfp_flags, migratetype);
 		goto out;