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-rw-r--r--include/linux/mmzone.h5
-rw-r--r--mm/page_alloc.c106
2 files changed, 63 insertions, 48 deletions
diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index c188ea624c7..652ef01be58 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -38,6 +38,7 @@
#define MIGRATE_UNMOVABLE 0
#define MIGRATE_RECLAIMABLE 1
#define MIGRATE_MOVABLE 2
+#define MIGRATE_PCPTYPES 3 /* the number of types on the pcp lists */
#define MIGRATE_RESERVE 3
#define MIGRATE_ISOLATE 4 /* can't allocate from here */
#define MIGRATE_TYPES 5
@@ -169,7 +170,9 @@ struct per_cpu_pages {
int count; /* number of pages in the list */
int high; /* high watermark, emptying needed */
int batch; /* chunk size for buddy add/remove */
- struct list_head list; /* the list of pages */
+
+ /* Lists of pages, one per migrate type stored on the pcp-lists */
+ struct list_head lists[MIGRATE_PCPTYPES];
};
struct per_cpu_pageset {
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 84d9da1e8f4..1b1c39e6a9b 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -511,7 +511,7 @@ static inline int free_pages_check(struct page *page)
}
/*
- * Frees a list of pages.
+ * Frees a number of pages from the PCP lists
* Assumes all pages on list are in same zone, and of same order.
* count is the number of pages to free.
*
@@ -521,23 +521,36 @@ static inline int free_pages_check(struct page *page)
* And clear the zone's pages_scanned counter, to hold off the "all pages are
* pinned" detection logic.
*/
-static void free_pages_bulk(struct zone *zone, int count,
- struct list_head *list, int order)
+static void free_pcppages_bulk(struct zone *zone, int count,
+ struct per_cpu_pages *pcp)
{
+ int migratetype = 0;
+
spin_lock(&zone->lock);
zone_clear_flag(zone, ZONE_ALL_UNRECLAIMABLE);
zone->pages_scanned = 0;
- __mod_zone_page_state(zone, NR_FREE_PAGES, count << order);
+ __mod_zone_page_state(zone, NR_FREE_PAGES, count);
while (count--) {
struct page *page;
+ struct list_head *list;
+
+ /*
+ * Remove pages from lists in a round-robin fashion. This spinning
+ * around potentially empty lists is bloody awful, alternatives that
+ * don't suck are welcome
+ */
+ do {
+ if (++migratetype == MIGRATE_PCPTYPES)
+ migratetype = 0;
+ list = &pcp->lists[migratetype];
+ } while (list_empty(list));
- VM_BUG_ON(list_empty(list));
page = list_entry(list->prev, struct page, lru);
/* have to delete it as __free_one_page list manipulates */
list_del(&page->lru);
- trace_mm_page_pcpu_drain(page, order, page_private(page));
- __free_one_page(page, zone, order, page_private(page));
+ trace_mm_page_pcpu_drain(page, 0, migratetype);
+ __free_one_page(page, zone, 0, migratetype);
}
spin_unlock(&zone->lock);
}
@@ -953,7 +966,7 @@ void drain_zone_pages(struct zone *zone, struct per_cpu_pages *pcp)
to_drain = pcp->batch;
else
to_drain = pcp->count;
- free_pages_bulk(zone, to_drain, &pcp->list, 0);
+ free_pcppages_bulk(zone, to_drain, pcp);
pcp->count -= to_drain;
local_irq_restore(flags);
}
@@ -979,7 +992,7 @@ static void drain_pages(unsigned int cpu)
pcp = &pset->pcp;
local_irq_save(flags);
- free_pages_bulk(zone, pcp->count, &pcp->list, 0);
+ free_pcppages_bulk(zone, pcp->count, pcp);
pcp->count = 0;
local_irq_restore(flags);
}
@@ -1045,6 +1058,7 @@ static void free_hot_cold_page(struct page *page, int cold)
struct zone *zone = page_zone(page);
struct per_cpu_pages *pcp;
unsigned long flags;
+ int migratetype;
int wasMlocked = __TestClearPageMlocked(page);
kmemcheck_free_shadow(page, 0);
@@ -1062,21 +1076,39 @@ static void free_hot_cold_page(struct page *page, int cold)
kernel_map_pages(page, 1, 0);
pcp = &zone_pcp(zone, get_cpu())->pcp;
- set_page_private(page, get_pageblock_migratetype(page));
+ migratetype = get_pageblock_migratetype(page);
+ set_page_private(page, migratetype);
local_irq_save(flags);
if (unlikely(wasMlocked))
free_page_mlock(page);
__count_vm_event(PGFREE);
+ /*
+ * We only track unmovable, reclaimable and movable on pcp lists.
+ * Free ISOLATE pages back to the allocator because they are being
+ * offlined but treat RESERVE 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) {
+ if (unlikely(migratetype == MIGRATE_ISOLATE)) {
+ free_one_page(zone, page, 0, migratetype);
+ goto out;
+ }
+ migratetype = MIGRATE_MOVABLE;
+ }
+
if (cold)
- list_add_tail(&page->lru, &pcp->list);
+ list_add_tail(&page->lru, &pcp->lists[migratetype]);
else
- list_add(&page->lru, &pcp->list);
+ list_add(&page->lru, &pcp->lists[migratetype]);
pcp->count++;
if (pcp->count >= pcp->high) {
- free_pages_bulk(zone, pcp->batch, &pcp->list, 0);
+ free_pcppages_bulk(zone, pcp->batch, pcp);
pcp->count -= pcp->batch;
}
+
+out:
local_irq_restore(flags);
put_cpu();
}
@@ -1134,46 +1166,24 @@ again:
cpu = get_cpu();
if (likely(order == 0)) {
struct per_cpu_pages *pcp;
+ struct list_head *list;
pcp = &zone_pcp(zone, cpu)->pcp;
+ list = &pcp->lists[migratetype];
local_irq_save(flags);
- if (!pcp->count) {
- pcp->count = rmqueue_bulk(zone, 0,
- pcp->batch, &pcp->list,
- migratetype, cold);
- if (unlikely(!pcp->count))
- goto failed;
- }
-
- /* Find a page of the appropriate migrate type */
- if (cold) {
- list_for_each_entry_reverse(page, &pcp->list, lru)
- if (page_private(page) == migratetype)
- break;
- } else {
- list_for_each_entry(page, &pcp->list, lru)
- if (page_private(page) == migratetype)
- break;
- }
-
- /* Allocate more to the pcp list if necessary */
- if (unlikely(&page->lru == &pcp->list)) {
- int get_one_page = 0;
-
+ if (list_empty(list)) {
pcp->count += rmqueue_bulk(zone, 0,
- pcp->batch, &pcp->list,
+ pcp->batch, list,
migratetype, cold);
- list_for_each_entry(page, &pcp->list, lru) {
- if (get_pageblock_migratetype(page) !=
- MIGRATE_ISOLATE) {
- get_one_page = 1;
- break;
- }
- }
- if (!get_one_page)
+ if (unlikely(list_empty(list)))
goto failed;
}
+ if (cold)
+ page = list_entry(list->prev, struct page, lru);
+ else
+ page = list_entry(list->next, struct page, lru);
+
list_del(&page->lru);
pcp->count--;
} else {
@@ -3024,6 +3034,7 @@ static int zone_batchsize(struct zone *zone)
static void setup_pageset(struct per_cpu_pageset *p, unsigned long batch)
{
struct per_cpu_pages *pcp;
+ int migratetype;
memset(p, 0, sizeof(*p));
@@ -3031,7 +3042,8 @@ static void setup_pageset(struct per_cpu_pageset *p, unsigned long batch)
pcp->count = 0;
pcp->high = 6 * batch;
pcp->batch = max(1UL, 1 * batch);
- INIT_LIST_HEAD(&pcp->list);
+ for (migratetype = 0; migratetype < MIGRATE_PCPTYPES; migratetype++)
+ INIT_LIST_HEAD(&pcp->lists[migratetype]);
}
/*
@@ -3223,7 +3235,7 @@ static int __zone_pcp_update(void *data)
pcp = &pset->pcp;
local_irq_save(flags);
- free_pages_bulk(zone, pcp->count, &pcp->list, 0);
+ free_pcppages_bulk(zone, pcp->count, pcp);
setup_pageset(pset, batch);
local_irq_restore(flags);
}