diff options
-rw-r--r-- | include/linux/mmzone.h | 5 | ||||
-rw-r--r-- | mm/page_alloc.c | 106 |
2 files changed, 63 insertions, 48 deletions
diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index c188ea624c74..652ef01be582 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 84d9da1e8f4c..1b1c39e6a9b8 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); } |