diff options
Diffstat (limited to 'mm/vmscan.c')
| -rw-r--r-- | mm/vmscan.c | 826 |
1 files changed, 468 insertions, 358 deletions
diff --git a/mm/vmscan.c b/mm/vmscan.c index 11adc890ce3..c52b2355265 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -26,7 +26,6 @@ #include <linux/buffer_head.h> /* for try_to_release_page(), buffer_heads_over_limit */ #include <linux/mm_inline.h> -#include <linux/pagevec.h> #include <linux/backing-dev.h> #include <linux/rmap.h> #include <linux/topology.h> @@ -103,8 +102,11 @@ struct scan_control { */ reclaim_mode_t reclaim_mode; - /* Which cgroup do we reclaim from */ - struct mem_cgroup *mem_cgroup; + /* + * The memory cgroup that hit its limit and as a result is the + * primary target of this reclaim invocation. + */ + struct mem_cgroup *target_mem_cgroup; /* * Nodemask of nodes allowed by the caller. If NULL, all nodes @@ -113,6 +115,11 @@ struct scan_control { nodemask_t *nodemask; }; +struct mem_cgroup_zone { + struct mem_cgroup *mem_cgroup; + struct zone *zone; +}; + #define lru_to_page(_head) (list_entry((_head)->prev, struct page, lru)) #ifdef ARCH_HAS_PREFETCH @@ -153,28 +160,45 @@ static LIST_HEAD(shrinker_list); static DECLARE_RWSEM(shrinker_rwsem); #ifdef CONFIG_CGROUP_MEM_RES_CTLR -#define scanning_global_lru(sc) (!(sc)->mem_cgroup) +static bool global_reclaim(struct scan_control *sc) +{ + return !sc->target_mem_cgroup; +} + +static bool scanning_global_lru(struct mem_cgroup_zone *mz) +{ + return !mz->mem_cgroup; +} #else -#define scanning_global_lru(sc) (1) +static bool global_reclaim(struct scan_control *sc) +{ + return true; +} + +static bool scanning_global_lru(struct mem_cgroup_zone *mz) +{ + return true; +} #endif -static struct zone_reclaim_stat *get_reclaim_stat(struct zone *zone, - struct scan_control *sc) +static struct zone_reclaim_stat *get_reclaim_stat(struct mem_cgroup_zone *mz) { - if (!scanning_global_lru(sc)) - return mem_cgroup_get_reclaim_stat(sc->mem_cgroup, zone); + if (!scanning_global_lru(mz)) + return mem_cgroup_get_reclaim_stat(mz->mem_cgroup, mz->zone); - return &zone->reclaim_stat; + return &mz->zone->reclaim_stat; } -static unsigned long zone_nr_lru_pages(struct zone *zone, - struct scan_control *sc, enum lru_list lru) +static unsigned long zone_nr_lru_pages(struct mem_cgroup_zone *mz, + enum lru_list lru) { - if (!scanning_global_lru(sc)) - return mem_cgroup_zone_nr_lru_pages(sc->mem_cgroup, - zone_to_nid(zone), zone_idx(zone), BIT(lru)); + if (!scanning_global_lru(mz)) + return mem_cgroup_zone_nr_lru_pages(mz->mem_cgroup, + zone_to_nid(mz->zone), + zone_idx(mz->zone), + BIT(lru)); - return zone_page_state(zone, NR_LRU_BASE + lru); + return zone_page_state(mz->zone, NR_LRU_BASE + lru); } @@ -636,7 +660,7 @@ redo: * When racing with an mlock or AS_UNEVICTABLE clearing * (page is unlocked) make sure that if the other thread * does not observe our setting of PG_lru and fails - * isolation/check_move_unevictable_page, + * isolation/check_move_unevictable_pages, * we see PG_mlocked/AS_UNEVICTABLE cleared below and move * the page back to the evictable list. * @@ -677,12 +701,13 @@ enum page_references { }; static enum page_references page_check_references(struct page *page, + struct mem_cgroup_zone *mz, struct scan_control *sc) { int referenced_ptes, referenced_page; unsigned long vm_flags; - referenced_ptes = page_referenced(page, 1, sc->mem_cgroup, &vm_flags); + referenced_ptes = page_referenced(page, 1, mz->mem_cgroup, &vm_flags); referenced_page = TestClearPageReferenced(page); /* Lumpy reclaim - ignore references */ @@ -715,7 +740,13 @@ static enum page_references page_check_references(struct page *page, */ SetPageReferenced(page); - if (referenced_page) + if (referenced_page || referenced_ptes > 1) + return PAGEREF_ACTIVATE; + + /* + * Activate file-backed executable pages after first usage. + */ + if (vm_flags & VM_EXEC) return PAGEREF_ACTIVATE; return PAGEREF_KEEP; @@ -728,29 +759,11 @@ static enum page_references page_check_references(struct page *page, return PAGEREF_RECLAIM; } -static noinline_for_stack void free_page_list(struct list_head *free_pages) -{ - struct pagevec freed_pvec; - struct page *page, *tmp; - - pagevec_init(&freed_pvec, 1); - - list_for_each_entry_safe(page, tmp, free_pages, lru) { - list_del(&page->lru); - if (!pagevec_add(&freed_pvec, page)) { - __pagevec_free(&freed_pvec); - pagevec_reinit(&freed_pvec); - } - } - - pagevec_free(&freed_pvec); -} - /* * shrink_page_list() returns the number of reclaimed pages */ static unsigned long shrink_page_list(struct list_head *page_list, - struct zone *zone, + struct mem_cgroup_zone *mz, struct scan_control *sc, int priority, unsigned long *ret_nr_dirty, @@ -781,7 +794,7 @@ static unsigned long shrink_page_list(struct list_head *page_list, goto keep; VM_BUG_ON(PageActive(page)); - VM_BUG_ON(page_zone(page) != zone); + VM_BUG_ON(page_zone(page) != mz->zone); sc->nr_scanned++; @@ -815,7 +828,7 @@ static unsigned long shrink_page_list(struct list_head *page_list, } } - references = page_check_references(page, sc); + references = page_check_references(page, mz, sc); switch (references) { case PAGEREF_ACTIVATE: goto activate_locked; @@ -1006,10 +1019,10 @@ keep_lumpy: * back off and wait for congestion to clear because further reclaim * will encounter the same problem */ - if (nr_dirty && nr_dirty == nr_congested && scanning_global_lru(sc)) - zone_set_flag(zone, ZONE_CONGESTED); + if (nr_dirty && nr_dirty == nr_congested && global_reclaim(sc)) + zone_set_flag(mz->zone, ZONE_CONGESTED); - free_page_list(&free_pages); + free_hot_cold_page_list(&free_pages, 1); list_splice(&ret_pages, page_list); count_vm_events(PGACTIVATE, pgactivate); @@ -1061,8 +1074,39 @@ int __isolate_lru_page(struct page *page, isolate_mode_t mode, int file) ret = -EBUSY; - if ((mode & ISOLATE_CLEAN) && (PageDirty(page) || PageWriteback(page))) - return ret; + /* + * To minimise LRU disruption, the caller can indicate that it only + * wants to isolate pages it will be able to operate on without + * blocking - clean pages for the most part. + * + * ISOLATE_CLEAN means that only clean pages should be isolated. This + * is used by reclaim when it is cannot write to backing storage + * + * ISOLATE_ASYNC_MIGRATE is used to indicate that it only wants to pages + * that it is possible to migrate without blocking + */ + if (mode & (ISOLATE_CLEAN|ISOLATE_ASYNC_MIGRATE)) { + /* All the caller can do on PageWriteback is block */ + if (PageWriteback(page)) + return ret; + + if (PageDirty(page)) { + struct address_space *mapping; + + /* ISOLATE_CLEAN means only clean pages */ + if (mode & ISOLATE_CLEAN) + return ret; + + /* + * Only pages without mappings or that have a + * ->migratepage callback are possible to migrate + * without blocking + */ + mapping = page_mapping(page); + if (mapping && !mapping->a_ops->migratepage) + return ret; + } + } if ((mode & ISOLATE_UNMAPPED) && page_mapped(page)) return ret; @@ -1091,25 +1135,36 @@ int __isolate_lru_page(struct page *page, isolate_mode_t mode, int file) * Appropriate locks must be held before calling this function. * * @nr_to_scan: The number of pages to look through on the list. - * @src: The LRU list to pull pages off. + * @mz: The mem_cgroup_zone to pull pages from. * @dst: The temp list to put pages on to. - * @scanned: The number of pages that were scanned. + * @nr_scanned: The number of pages that were scanned. * @order: The caller's attempted allocation order * @mode: One of the LRU isolation modes + * @active: True [1] if isolating active pages * @file: True [1] if isolating file [!anon] pages * * returns how many pages were moved onto *@dst. */ static unsigned long isolate_lru_pages(unsigned long nr_to_scan, - struct list_head *src, struct list_head *dst, - unsigned long *scanned, int order, isolate_mode_t mode, - int file) + struct mem_cgroup_zone *mz, struct list_head *dst, + unsigned long *nr_scanned, int order, isolate_mode_t mode, + int active, int file) { + struct lruvec *lruvec; + struct list_head *src; unsigned long nr_taken = 0; unsigned long nr_lumpy_taken = 0; unsigned long nr_lumpy_dirty = 0; unsigned long nr_lumpy_failed = 0; unsigned long scan; + int lru = LRU_BASE; + + lruvec = mem_cgroup_zone_lruvec(mz->zone, mz->mem_cgroup); + if (active) + lru += LRU_ACTIVE; + if (file) + lru += LRU_FILE; + src = &lruvec->lists[lru]; for (scan = 0; scan < nr_to_scan && !list_empty(src); scan++) { struct page *page; @@ -1125,15 +1180,14 @@ static unsigned long isolate_lru_pages(unsigned long nr_to_scan, switch (__isolate_lru_page(page, mode, file)) { case 0: + mem_cgroup_lru_del(page); list_move(&page->lru, dst); - mem_cgroup_del_lru(page); nr_taken += hpage_nr_pages(page); break; case -EBUSY: /* else it is being freed elsewhere */ list_move(&page->lru, src); - mem_cgroup_rotate_lru_list(page, page_lru(page)); continue; default: @@ -1178,18 +1232,22 @@ static unsigned long isolate_lru_pages(unsigned long nr_to_scan, * anon page which don't already have a swap slot is * pointless. */ - if (nr_swap_pages <= 0 && PageAnon(cursor_page) && + if (nr_swap_pages <= 0 && PageSwapBacked(cursor_page) && !PageSwapCache(cursor_page)) break; if (__isolate_lru_page(cursor_page, mode, file) == 0) { + unsigned int isolated_pages; + + mem_cgroup_lru_del(cursor_page); list_move(&cursor_page->lru, dst); - mem_cgroup_del_lru(cursor_page); - nr_taken += hpage_nr_pages(page); - nr_lumpy_taken++; + isolated_pages = hpage_nr_pages(cursor_page); + nr_taken += isolated_pages; + nr_lumpy_taken += isolated_pages; if (PageDirty(cursor_page)) - nr_lumpy_dirty++; + nr_lumpy_dirty += isolated_pages; scan++; + pfn += isolated_pages - 1; } else { /* * Check if the page is freed already. @@ -1215,57 +1273,16 @@ static unsigned long isolate_lru_pages(unsigned long nr_to_scan, nr_lumpy_failed++; } - *scanned = scan; + *nr_scanned = scan; trace_mm_vmscan_lru_isolate(order, nr_to_scan, scan, nr_taken, nr_lumpy_taken, nr_lumpy_dirty, nr_lumpy_failed, - mode); + mode, file); return nr_taken; } -static unsigned long isolate_pages_global(unsigned long nr, - struct list_head *dst, - unsigned long *scanned, int order, - isolate_mode_t mode, - struct zone *z, int active, int file) -{ - int lru = LRU_BASE; - if (active) - lru += LRU_ACTIVE; - if (file) - lru += LRU_FILE; - return isolate_lru_pages(nr, &z->lru[lru].list, dst, scanned, order, - mode, file); -} - -/* - * clear_active_flags() is a helper for shrink_active_list(), clearing - * any active bits from the pages in the list. - */ -static unsigned long clear_active_flags(struct list_head *page_list, - unsigned int *count) -{ - int nr_active = 0; - int lru; - struct page *page; - - list_for_each_entry(page, page_list, lru) { - int numpages = hpage_nr_pages(page); - lru = page_lru_base_type(page); - if (PageActive(page)) { - lru += LRU_ACTIVE; - ClearPageActive(page); - nr_active += numpages; - } - if (count) - count[lru] += numpages; - } - - return nr_active; -} - /** * isolate_lru_page - tries to isolate a page from its LRU list * @page: page to isolate from its LRU list @@ -1325,7 +1342,7 @@ static int too_many_isolated(struct zone *zone, int file, if (current_is_kswapd()) return 0; - if (!scanning_global_lru(sc)) + if (!global_reclaim(sc)) return 0; if (file) { @@ -1339,27 +1356,21 @@ static int too_many_isolated(struct zone *zone, int file, return isolated > inactive; } -/* - * TODO: Try merging with migrations version of putback_lru_pages - */ static noinline_for_stack void -putback_lru_pages(struct zone *zone, struct scan_control *sc, - unsigned long nr_anon, unsigned long nr_file, - struct list_head *page_list) +putback_inactive_pages(struct mem_cgroup_zone *mz, + struct list_head *page_list) { - struct page *page; - struct pagevec pvec; - struct zone_reclaim_stat *reclaim_stat = get_reclaim_stat(zone, sc); - - pagevec_init(&pvec, 1); + struct zone_reclaim_stat *reclaim_stat = get_reclaim_stat(mz); + struct zone *zone = mz->zone; + LIST_HEAD(pages_to_free); /* * Put back any unfreeable pages. */ - spin_lock(&zone->lru_lock); while (!list_empty(page_list)) { + struct page *page = lru_to_page(page_list); int lru; - page = lru_to_page(page_list); + VM_BUG_ON(PageLRU(page)); list_del(&page->lru); if (unlikely(!page_evictable(page, NULL))) { @@ -1376,30 +1387,53 @@ putback_lru_pages(struct zone *zone, struct scan_control *sc, int numpages = hpage_nr_pages(page); reclaim_stat->recent_rotated[file] += numpages; } - if (!pagevec_add(&pvec, page)) { - spin_unlock_irq(&zone->lru_lock); - __pagevec_release(&pvec); - spin_lock_irq(&zone->lru_lock); + if (put_page_testzero(page)) { + __ClearPageLRU(page); + __ClearPageActive(page); + del_page_from_lru_list(zone, page, lru); + + if (unlikely(PageCompound(page))) { + spin_unlock_irq(&zone->lru_lock); + (*get_compound_page_dtor(page))(page); + spin_lock_irq(&zone->lru_lock); + } else + list_add(&page->lru, &pages_to_free); } } - __mod_zone_page_state(zone, NR_ISOLATED_ANON, -nr_anon); - __mod_zone_page_state(zone, NR_ISOLATED_FILE, -nr_file); - spin_unlock_irq(&zone->lru_lock); - pagevec_release(&pvec); + /* + * To save our caller's stack, now use input list for pages to free. + */ + list_splice(&pages_to_free, page_list); } -static noinline_for_stack void update_isolated_counts(struct zone *zone, - struct scan_control *sc, - unsigned long *nr_anon, - unsigned long *nr_file, - struct list_head *isolated_list) +static noinline_for_stack void +update_isolated_counts(struct mem_cgroup_zone *mz, + struct list_head *page_list, + unsigned long *nr_anon, + unsigned long *nr_file) { - unsigned long nr_active; + struct zone_reclaim_stat *reclaim_stat = get_reclaim_stat(mz); + struct zone *zone = mz->zone; unsigned int count[NR_LRU_LISTS] = { 0, }; - struct zone_reclaim_stat *reclaim_stat = get_reclaim_stat(zone, sc); + unsigned long nr_active = 0; + struct page *page; + int lru; + + /* + * Count pages and clear active flags + */ + list_for_each_entry(page, page_list, lru) { + int numpages = hpage_nr_pages(page); + lru = page_lru_base_type(page); + if (PageActive(page)) { + lru += LRU_ACTIVE; + ClearPageActive(page); + nr_active += numpages; + } + count[lru] += numpages; + } - nr_active = clear_active_flags(isolated_list, count); __count_vm_events(PGDEACTIVATE, nr_active); __mod_zone_page_state(zone, NR_ACTIVE_FILE, @@ -1413,8 +1447,6 @@ static noinline_for_stack void update_isolated_counts(struct zone *zone, *nr_anon = count[LRU_ACTIVE_ANON] + count[LRU_INACTIVE_ANON]; *nr_file = count[LRU_ACTIVE_FILE] + count[LRU_INACTIVE_FILE]; - __mod_zone_page_state(zone, NR_ISOLATED_ANON, *nr_anon); - __mod_zone_page_state(zone, NR_ISOLATED_FILE, *nr_file); reclaim_stat->recent_scanned[0] += *nr_anon; reclaim_stat->recent_scanned[1] += *nr_file; @@ -1466,8 +1498,8 @@ static inline bool should_reclaim_stall(unsigned long nr_taken, * of reclaimed pages */ static noinline_for_stack unsigned long -shrink_inactive_list(unsigned long nr_to_scan, struct zone *zone, - struct scan_control *sc, int priority, int file) +shrink_inactive_list(unsigned long nr_to_scan, struct mem_cgroup_zone *mz, + struct scan_control *sc, int priority, int file) { LIST_HEAD(page_list); unsigned long nr_scanned; @@ -1478,6 +1510,7 @@ shrink_inactive_list(unsigned long nr_to_scan, struct zone *zone, unsigned long nr_dirty = 0; unsigned long nr_writeback = 0; isolate_mode_t reclaim_mode = ISOLATE_INACTIVE; + struct zone *zone = mz->zone; while (unlikely(too_many_isolated(zone, file, sc))) { congestion_wait(BLK_RW_ASYNC, HZ/10); @@ -1500,9 +1533,10 @@ shrink_inactive_list(unsigned long nr_to_scan, struct zone *zone, spin_lock_irq(&zone->lru_lock); - if (scanning_global_lru(sc)) { - nr_taken = isolate_pages_global(nr_to_scan, &page_list, - &nr_scanned, sc->order, reclaim_mode, zone, 0, file); + nr_taken = isolate_lru_pages(nr_to_scan, mz, &page_list, + &nr_scanned, sc->order, + reclaim_mode, 0, file); + if (global_reclaim(sc)) { zone->pages_scanned += nr_scanned; if (current_is_kswapd()) __count_zone_vm_events(PGSCAN_KSWAPD, zone, @@ -1510,14 +1544,6 @@ shrink_inactive_list(unsigned long nr_to_scan, struct zone *zone, else __count_zone_vm_events(PGSCAN_DIRECT, zone, nr_scanned); - } else { - nr_taken = mem_cgroup_isolate_pages(nr_to_scan, &page_list, - &nr_scanned, sc->order, reclaim_mode, zone, - sc->mem_cgroup, 0, file); - /* - * mem_cgroup_isolate_pages() keeps track of - * scanned pages on its own. - */ } if (nr_taken == 0) { @@ -1525,26 +1551,37 @@ shrink_inactive_list(unsigned long nr_to_scan, struct zone *zone, return 0; } - update_isolated_counts(zone, sc, &nr_anon, &nr_file, &page_list); + update_isolated_counts(mz, &page_list, &nr_anon, &nr_file); + + __mod_zone_page_state(zone, NR_ISOLATED_ANON, nr_anon); + __mod_zone_page_state(zone, NR_ISOLATED_FILE, nr_file); spin_unlock_irq(&zone->lru_lock); - nr_reclaimed = shrink_page_list(&page_list, zone, sc, priority, + nr_reclaimed = shrink_page_list(&page_list, mz, sc, priority, &nr_dirty, &nr_writeback); /* Check if we should syncronously wait for writeback */ if (should_reclaim_stall(nr_taken, nr_reclaimed, priority, sc)) { set_reclaim_mode(priority, sc, true); - nr_reclaimed += shrink_page_list(&page_list, zone, sc, + nr_reclaimed += shrink_page_list(&page_list, mz, sc, priority, &nr_dirty, &nr_writeback); } - local_irq_disable(); + spin_lock_irq(&zone->lru_lock); + if (current_is_kswapd()) __count_vm_events(KSWAPD_STEAL, nr_reclaimed); __count_zone_vm_events(PGSTEAL, zone, nr_reclaimed); - putback_lru_pages(zone, sc, nr_anon, nr_file, &page_list); + putback_inactive_pages(mz, &page_list); + + __mod_zone_page_state(zone, NR_ISOLATED_ANON, -nr_anon); + __mod_zone_page_state(zone, NR_ISOLATED_FILE, -nr_file); + + spin_unlock_irq(&zone->lru_lock); + + free_hot_cold_page_list(&page_list, 1); /* * If reclaim is isolating dirty pages under writeback, it implies @@ -1600,30 +1637,47 @@ shrink_inactive_list(unsigned long nr_to_scan, struct zone *zone, static void move_active_pages_to_lru(struct zone *zone, struct list_head *list, + struct list_head *pages_to_free, enum lru_list lru) { unsigned long pgmoved = 0; - struct pagevec pvec; struct page *page; - pagevec_init(&pvec, 1); + if (buffer_heads_over_limit) { + spin_unlock_irq(&zone->lru_lock); + list_for_each_entry(page, list, lru) { + if (page_has_private(page) && trylock_page(page)) { + if (page_has_private(page)) + try_to_release_page(page, 0); + unlock_page(page); + } + } + spin_lock_irq(&zone->lru_lock); + } while (!list_empty(list)) { + struct lruvec *lruvec; + page = lru_to_page(list); VM_BUG_ON(PageLRU(page)); SetPageLRU(page); - list_move(&page->lru, &zone->lru[lru].list); - mem_cgroup_add_lru_list(page, lru); + lruvec = mem_cgroup_lru_add_list(zone, page, lru); + list_move(&page->lru, &lruvec->lists[lru]); pgmoved += hpage_nr_pages(page); - if (!pagevec_add(&pvec, page) || list_empty(list)) { - spin_unlock_irq(&zone->lru_lock); - if (buffer_heads_over_limit) - pagevec_strip(&pvec); - __pagevec_release(&pvec); - spin_lock_irq(&zone->lru_lock); + if (put_page_testzero(page)) { + __ClearPageLRU(page); + __ClearPageActive(page); + del_page_from_lru_list(zone, page, lru); + + if (unlikely(PageCompound(page))) { + spin_unlock_irq(&zone->lru_lock); + (*get_compound_page_dtor(page))(page); + spin_lock_irq(&zone->lru_lock); + } else + list_add(&page->lru, pages_to_free); } } __mod_zone_page_state(zone, NR_LRU_BASE + lru, pgmoved); @@ -1631,19 +1685,22 @@ static void move_active_pages_to_lru(struct zone *zone, __count_vm_events(PGDEACTIVATE, pgmoved); } -static void shrink_active_list(unsigned long nr_pages, struct zone *zone, - struct scan_control *sc, int priority, int file) +static void shrink_active_list(unsigned long nr_to_scan, + struct mem_cgroup_zone *mz, + struct scan_control *sc, + int priority, int file) { unsigned long nr_taken; - unsigned long pgscanned; + unsigned long nr_scanned; unsigned long vm_flags; LIST_HEAD(l_hold); /* The pages which were snipped off */ LIST_HEAD(l_active); LIST_HEAD(l_inactive); struct page *page; - struct zone_reclaim_stat *reclaim_stat = get_reclaim_stat(zone, sc); + struct zone_reclaim_stat *reclaim_stat = get_reclaim_stat(mz); unsigned long nr_rotated = 0; isolate_mode_t reclaim_mode = ISOLATE_ACTIVE; + struct zone *zone = mz->zone; lru_add_drain(); @@ -1653,26 +1710,16 @@ static void shrink_active_list(unsigned long nr_pages, struct zone *zone, reclaim_mode |= ISOLATE_CLEAN; spin_lock_irq(&zone->lru_lock); - if (scanning_global_lru(sc)) { - nr_taken = isolate_pages_global(nr_pages, &l_hold, - &pgscanned, sc->order, - reclaim_mode, zone, - 1, file); - zone->pages_scanned += pgscanned; - } else { - nr_taken = mem_cgroup_isolate_pages(nr_pages, &l_hold, - &pgscanned, sc->order, - reclaim_mode, zone, - sc->mem_cgroup, 1, file); - /* - * mem_cgroup_isolate_pages() keeps track of - * scanned pages on its own. - */ - } + + nr_taken = isolate_lru_pages(nr_to_scan, mz, &l_hold, + &nr_scanned, sc->order, + reclaim_mode, 1, file); + if (global_reclaim(sc)) + zone->pages_scanned += nr_scanned; reclaim_stat->recent_scanned[file] += nr_taken; - __count_zone_vm_events(PGREFILL, zone, pgscanned); + __count_zone_vm_events(PGREFILL, zone, nr_scanned); if (file) __mod_zone_page_state(zone, NR_ACTIVE_FILE, -nr_taken); else @@ -1690,7 +1737,7 @@ static void shrink_active_list(unsigned long nr_pages, struct zone *zone, continue; } - if (page_referenced(page, 0, sc->mem_cgroup, &vm_flags)) { + if (page_referenced(page, 0, mz->mem_cgroup, &vm_flags)) { nr_rotated += hpage_nr_pages(page); /* * Identify referenced, file-backed active pages and @@ -1723,12 +1770,14 @@ static void shrink_active_list(unsigned long nr_pages, struct zone *zone, */ reclaim_stat->recent_rotated[file] += nr_rotated; - move_active_pages_to_lru(zone, &l_active, + move_active_pages_to_lru(zone, &l_active, &l_hold, LRU_ACTIVE + file * LRU_FILE); - move_active_pages_to_lru(zone, &l_inactive, + move_active_pages_to_lru(zone, &l_inactive, &l_hold, LRU_BASE + file * LRU_FILE); __mod_zone_page_state(zone, NR_ISOLATED_ANON + file, -nr_taken); spin_unlock_irq(&zone->lru_lock); + + free_hot_cold_page_list(&l_hold, 1); } #ifdef CONFIG_SWAP @@ -1753,10 +1802,8 @@ static int inactive_anon_is_low_global(struct zone *zone) * Returns true if the zone does not have enough inactive anon pages, * meaning some active anon pages need to be deactivated. */ -static int inactive_anon_is_low(struct zone *zone, struct scan_control *sc) +static int inactive_anon_is_low(struct mem_cgroup_zone *mz) { - int low; - /* * If we don't have swap space, anonymous page deactivation * is pointless. @@ -1764,15 +1811,14 @@ static int inactive_anon_is_low(struct zone *zone, struct scan_control *sc) if (!total_swap_pages) return 0; - if (scanning_global_lru(sc)) - low = inactive_anon_is_low_global(zone); - else - low = mem_cgroup_inactive_anon_is_low(sc->mem_cgroup, zone); - return low; + if (!scanning_global_lru(mz)) + return mem_cgroup_inactive_anon_is_low(mz->mem_cgroup, + mz->zone); + + return inactive_anon_is_low_global(mz->zone); } #else -static inline int inactive_anon_is_low(struct zone *zone, - struct scan_control *sc) +static inline int inactive_anon_is_low(struct mem_cgroup_zone *mz) { return 0; } @@ -1790,8 +1836,7 @@ static int inactive_file_is_low_global(struct zone *zone) /** * inactive_file_is_low - check if file pages need to be deactivated - * @zone: zone to check - * @sc: scan control of this context + * @mz: memory cgroup and zone to check * * When the system is doing streaming IO, memory pressure here * ensures that active file pages get deactivated, until more @@ -1803,45 +1848,44 @@ static int inactive_file_is_low_global(struct zone *zone) * This uses a different ratio than the anonymous pages, because * the page cache uses a use-once replacement algorithm. */ -static int inactive_file_is_low(struct zone *zone, struct scan_control *sc) +static int inactive_file_is_low(struct mem_cgroup_zone *mz) { - int low; + if (!scanning_global_lru(mz)) + return mem_cgroup_inactive_file_is_low(mz->mem_cgroup, + mz->zone); - if (scanning_global_lru(sc)) - low = inactive_file_is_low_global(zone); - else - low = mem_cgroup_inactive_file_is_low(sc->mem_cgroup, zone); - return low; + return inactive_file_is_low_global(mz->zone); } -static int inactive_list_is_low(struct zone *zone, struct scan_control *sc, - int file) +static int inactive_list_is_low(struct mem_cgroup_zone *mz, int file) { if (file) - return inactive_file_is_low(zone, sc); + return inactive_file_is_low(mz); else - return inactive_anon_is_low(zone, sc); + return inactive_anon_is_low(mz); } static unsigned long shrink_list(enum lru_list lru, unsigned long nr_to_scan, - struct zone *zone, struct scan_control *sc, int priority) + struct mem_cgroup_zone *mz, + struct scan_control *sc, int priority) { int file = is_file_lru(lru); if (is_active_lru(lru)) { - if (inactive_list_is_low(zone, sc, file)) - shrink_active_list(nr_to_scan, zone, sc, priority, file); + if (inactive_list_is_low(mz, file)) + shrink_active_list(nr_to_scan, mz, sc, priority, file); return 0; } - return shrink_inactive_list(nr_to_scan, zone, sc, priority, file); + return shrink_inactive_list(nr_to_scan, mz, sc, priority, file); } -static int vmscan_swappiness(struct scan_control *sc) +static int vmscan_swappiness(struct mem_cgroup_zone *mz, + struct scan_control *sc) { - if (scanning_global_lru(sc)) + if (global_reclaim(sc)) return vm_swappiness; - return mem_cgroup_swappiness(sc->mem_cgroup); + return mem_cgroup_swappiness(mz->mem_cgroup); } /* @@ -1852,15 +1896,15 @@ static int vmscan_swappiness(struct scan_control *sc) * * nr[0] = anon pages to scan; nr[1] = file pages to scan */ -static void get_scan_count(struct zone *zone, struct scan_control *sc, - unsigned long *nr, int priority) +static void get_scan_count(struct mem_cgroup_zone *mz, struct scan_control *sc, + unsigned long *nr, int priority) { unsigned long anon, file, free; unsigned long anon_prio, file_prio; unsigned long ap, fp; - struct zone_reclaim_stat *reclaim_stat = get_reclaim_stat(zone, sc); + struct zone_reclaim_stat *reclaim_stat = get_reclaim_stat(mz); u64 fraction[2], denominator; - enum lru_list l; + enum lru_list lru; int noswap = 0; bool force_scan = false; @@ -1874,9 +1918,9 @@ static void get_scan_count(struct zone *zone, struct scan_control *sc, * latencies, so it's better to scan a minimum amount there as * well. */ - if (scanning_global_lru(sc) && current_is_kswapd()) + if (current_is_kswapd() && mz->zone->all_unreclaimable) force_scan = true; - if (!scanning_global_lru(sc)) + if (!global_reclaim(sc)) force_scan = true; /* If we have no swap space, do not bother scanning anon pages. */ @@ -1888,16 +1932,16 @@ static void get_scan_count(struct zone *zone, struct scan_control *sc, goto out; } - anon = zone_nr_lru_pages(zone, sc, LRU_ACTIVE_ANON) + - zone_nr_lru_pages(zone, sc, LRU_INACTIVE_ANON); - file = zone_nr_lru_pages(zone, sc, LRU_ACTIVE_FILE) + - zone_nr_lru_pages(zone, sc, LRU_INACTIVE_FILE); + anon = zone_nr_lru_pages(mz, LRU_ACTIVE_ANON) + + zone_nr_lru_pages(mz, LRU_INACTIVE_ANON); + file = zone_nr_lru_pages(mz, LRU_ACTIVE_FILE) + + zone_nr_lru_pages(mz, LRU_INACTIVE_FILE); - if (scanning_global_lru(sc)) { - free = zone_page_state(zone, NR_FREE_PAGES); + if (global_reclaim(sc)) { + free = zone_page_state(mz->zone, NR_FREE_PAGES); /* If we have very few page cache pages, force-scan anon pages. */ - if (unlikely(file + free <= high_wmark_pages(zone))) { + if (unlikely(file + free <= high_wmark_pages(mz->zone))) { fraction[0] = 1; fraction[1] = 0; denominator = 1; @@ -1909,8 +1953,8 @@ static void get_scan_count(struct zone *zone, struct scan_control *sc, * With swappiness at 100, anonymous and file have the same priority. * This scanning priority is essentially the inverse of IO cost. */ - anon_prio = vmscan_swappiness(sc); - file_prio = 200 - vmscan_swappiness(sc); + anon_prio = vmscan_swappiness(mz, sc); + file_prio = 200 - vmscan_swappiness(mz, sc); /* * OK, so we have swap space and a fair amount of page cache @@ -1923,7 +1967,7 @@ static void get_scan_count(struct zone *zone, struct scan_control *sc, * * anon in [0], file in [1] */ - spin_lock_irq(&zone->lru_lock); + spin_lock_irq(&mz->zone->lru_lock); if (unlikely(reclaim_stat->recent_scanned[0] > anon / 4)) { reclaim_stat->recent_scanned[0] /= 2; reclaim_stat->recent_rotated[0] /= 2; @@ -1944,24 +1988,24 @@ static void get_scan_count(struct zone *zone, struct scan_control *sc, fp = (file_prio + 1) * (reclaim_stat->recent_scanned[1] + 1); fp /= reclaim_stat->recent_rotated[1] + 1; - spin_unlock_irq(&zone->lru_lock); + spin_unlock_irq(&mz->zone->lru_lock); fraction[0] = ap; fraction[1] = fp; denominator = ap + fp + 1; out: - for_each_evictable_lru(l) { - int file = is_file_lru(l); + for_each_evictable_lru(lru) { + int file = is_file_lru(lru); unsigned long scan; - scan = zone_nr_lru_pages(zone, sc, l); + scan = zone_nr_lru_pages(mz, lru); if (priority || noswap) { scan >>= priority; if (!scan && force_scan) scan = SWAP_CLUSTER_MAX; scan = div64_u64(scan * fraction[file], denominator); } - nr[l] = scan; + nr[lru] = scan; } } @@ -1972,7 +2016,7 @@ out: * back to the allocator and call try_to_compact_zone(), we ensure that * there are enough free pages for it to be likely successful */ -static inline bool should_continue_reclaim(struct zone *zone, +static inline bool should_continue_reclaim(struct mem_cgroup_zone *mz, unsigned long nr_reclaimed, unsigned long nr_scanned, struct scan_control *sc) @@ -2012,14 +2056,15 @@ static inline bool should_continue_reclaim(struct zone *zone, * inactive lists are large enough, continue reclaiming */ pages_for_compaction = (2UL << sc->order); - inactive_lru_pages = zone_nr_lru_pages(zone, sc, LRU_INACTIVE_ANON) + - zone_nr_lru_pages(zone, sc, LRU_INACTIVE_FILE); + inactive_lru_pages = zone_nr_lru_pages(mz, LRU_INACTIVE_FILE); + if (nr_swap_pages > 0) + inactive_lru_pages += zone_nr_lru_pages(mz, LRU_INACTIVE_ANON); if (sc->nr_reclaimed < pages_for_compaction && inactive_lru_pages > pages_for_compaction) return true; /* If compaction would go ahead or the allocation would succeed, stop */ - switch (compaction_suitable(zone, sc->order)) { + switch (compaction_suitable(mz->zone, sc->order)) { case COMPACT_PARTIAL: case COMPACT_CONTINUE: return false; @@ -2031,12 +2076,12 @@ static inline bool should_continue_reclaim(struct zone *zone, /* * This is a basic per-zone page freer. Used by both kswapd and direct reclaim. */ -static void shrink_zone(int priority, struct zone *zone, - struct scan_control *sc) +static void shrink_mem_cgroup_zone(int priority, struct mem_cgroup_zone *mz, + struct scan_control *sc) { unsigned long nr[NR_LRU_LISTS]; unsigned long nr_to_scan; - enum lru_list l; + enum lru_list lru; unsigned long nr_reclaimed, nr_scanned; unsigned long nr_to_reclaim = sc->nr_to_reclaim; struct blk_plug plug; @@ -2044,19 +2089,19 @@ static void shrink_zone(int priority, struct zone *zone, restart: nr_reclaimed = 0; nr_scanned = sc->nr_scanned; - get_scan_count(zone, sc, nr, priority); + get_scan_count(mz, sc, nr, priority); blk_start_plug(&plug); while (nr[LRU_INACTIVE_ANON] || nr[LRU_ACTIVE_FILE] || nr[LRU_INACTIVE_FILE]) { - for_each_evictable_lru(l) { - if (nr[l]) { + for_each_evictable_lru(lru) { + if (nr[lru]) { nr_to_scan = min_t(unsigned long, - nr[l], SWAP_CLUSTER_MAX); - nr[l] -= nr_to_scan; + nr[lru], SWAP_CLUSTER_MAX); + nr[lru] -= nr_to_scan; - nr_reclaimed += shrink_list(l, nr_to_scan, - zone, sc, priority); + nr_reclaimed += shrink_list(lru, nr_to_scan, + mz, sc, priority); } } /* @@ -2077,17 +2122,89 @@ restart: * Even if we did not try to evict anon pages at all, we want to * rebalance the anon lru active/inactive ratio. */ - if (inactive_anon_is_low(zone, sc)) - shrink_active_list(SWAP_CLUSTER_MAX, zone, sc, priority, 0); + if (inactive_anon_is_low(mz)) + shrink_active_list(SWAP_CLUSTER_MAX, mz, sc, priority, 0); /* reclaim/compaction might need reclaim to continue */ - if (should_continue_reclaim(zone, nr_reclaimed, + if (should_continue_reclaim(mz, nr_reclaimed, sc->nr_scanned - nr_scanned, sc)) goto restart; throttle_vm_writeout(sc->gfp_mask); } +static void shrink_zone(int priority, struct zone *zone, + struct scan_control *sc) +{ + struct mem_cgroup *root = sc->target_mem_cgroup; + struct mem_cgroup_reclaim_cookie reclaim = { + .zone = zone, + .priority = priority, + }; + struct mem_cgroup *memcg; + + memcg = mem_cgroup_iter(root, NULL, &reclaim); + do { + struct mem_cgroup_zone mz = { + .mem_cgroup = memcg, + .zone = zone, + }; + + shrink_mem_cgroup_zone(priority, &mz, sc); + /* + * Limit reclaim has historically picked one memcg and + * scanned it with decreasing priority levels until + * nr_to_reclaim had been reclaimed. This priority + * cycle is thus over after a single memcg. + * + * Direct reclaim and kswapd, on the other hand, have + * to scan all memory cgroups to fulfill the overall + * scan target for the zone. + */ + if (!global_reclaim(sc)) { + mem_cgroup_iter_break(root, memcg); + break; + } + memcg = mem_cgroup_iter(root, memcg, &reclaim); + } while (memcg); +} + +/* Returns true if compaction should go ahead for a high-order request */ +static inline bool compaction_ready(struct zone *zone, struct scan_control *sc) +{ + unsigned long balance_gap, watermark; + bool watermark_ok; + + /* Do not consider compaction for orders reclaim is meant to satisfy */ + if (sc->order <= PAGE_ALLOC_COSTLY_ORDER) + return false; + + /* + * Compaction takes time to run and there are potentially other + * callers using the pages just freed. Continue reclaiming until + * there is a buffer of free pages available to give compaction + * a reasonable chance of completing and allocating the page + */ + balance_gap = min(low_wmark_pages(zone), + (zone->present_pages + KSWAPD_ZONE_BALANCE_GAP_RATIO-1) / + KSWAPD_ZONE_BALANCE_GAP_RATIO); + watermark = high_wmark_pages(zone) + balance_gap + (2UL << sc->order); + watermark_ok = zone_watermark_ok_safe(zone, 0, watermark, 0, 0); + + /* + * If compaction is deferred, reclaim up to a point where + * compaction will have a chance of success when re-enabled + */ + if (compaction_deferred(zone)) + return watermark_ok; + + /* If compaction is not ready to start, keep reclaiming */ + if (!compaction_suitable(zone, sc->order)) + return false; + + return watermark_ok; +} + /* * This is the direct reclaim path, for page-allocating processes. We only * try to reclaim pages from zones which will satisfy the caller's allocation @@ -2105,8 +2222,9 @@ restart: * scan then give up on it. * * This function returns true if a zone is being reclaimed for a costly - * high-order allocation and compaction is either ready to begin or deferred. - * This indicates to the caller that it should retry the allocation or fail. + * high-order allocation and compaction is ready to begin. This indicates to + * the caller that it should consider retrying the allocation instead of + * further reclaim. */ static bool shrink_zones(int priority, struct zonelist *zonelist, struct scan_control *sc) @@ -2115,7 +2233,7 @@ static bool shrink_zones(int priority, struct zonelist *zonelist, struct zone *zone; unsigned long nr_soft_reclaimed; unsigned long nr_soft_scanned; - bool should_abort_reclaim = false; + bool aborted_reclaim = false; for_each_zone_zonelist_nodemask(zone, z, zonelist, gfp_zone(sc->gfp_mask), sc->nodemask) { @@ -2125,7 +2243,7 @@ static bool shrink_zones(int priority, struct zonelist *zonelist, * Take care memory controller reclaiming has small influence * to global LRU. */ - if (scanning_global_lru(sc)) { + if (global_reclaim(sc)) { if (!cpuset_zone_allowed_hardwall(zone, GFP_KERNEL)) continue; if (zone->all_unreclaimable && priority != DEF_PRIORITY) @@ -2140,10 +2258,8 @@ static bool shrink_zones(int priority, struct zonelist *zonelist, * noticable problem, like transparent huge page * allocations. */ - if (sc->order > PAGE_ALLOC_COSTLY_ORDER && - (compaction_suitable(zone, sc->order) || - compaction_deferred(zone))) { - should_abort_reclaim = true; + if (compaction_ready(zone, sc)) { + aborted_reclaim = true; continue; } } @@ -2165,7 +2281,7 @@ static bool shrink_zones(int priority, struct zonelist *zonelist, shrink_zone(priority, zone, sc); } - return should_abort_reclaim; + return aborted_reclaim; } static bool zone_reclaimable(struct zone *zone) @@ -2219,25 +2335,25 @@ static unsigned long do_try_to_free_pages(struct zonelist *zonelist, struct zoneref *z; struct zone *zone; unsigned long writeback_threshold; + bool aborted_reclaim; get_mems_allowed(); delayacct_freepages_start(); - if (scanning_global_lru(sc)) + if (global_reclaim(sc)) count_vm_event(ALLOCSTALL); for (priority = DEF_PRIORITY; priority >= 0; priority--) { sc->nr_scanned = 0; if (!priority) - disable_swap_token(sc->mem_cgroup); - if (shrink_zones(priority, zonelist, sc)) - break; + disable_swap_token(sc->target_mem_cgroup); + aborted_reclaim = shrink_zones(priority, zonelist, sc); /* * Don't shrink slabs when reclaiming memory from * over limit cgroups */ - if (scanning_global_lru(sc)) { + if (global_reclaim(sc)) { unsigned long lru_pages = 0; for_each_zone_zonelist(zone, z, zonelist, gfp_zone(sc->gfp_mask)) { @@ -2298,8 +2414,12 @@ out: if (oom_killer_disabled) return 0; + /* Aborted reclaim to try compaction? don't OOM, then */ + if (aborted_reclaim) + return 1; + /* top priority shrink_zones still had more to do? don't OOM, then */ - if (scanning_global_lru(sc) && !all_unreclaimable(zonelist, sc)) + if (global_reclaim(sc) && !all_unreclaimable(zonelist, sc)) return 1; return 0; @@ -2316,7 +2436,7 @@ unsigned long try_to_free_pages(struct zonelist *zonelist, int order, .may_unmap = 1, .may_swap = 1, .order = order, - .mem_cgroup = NULL, + .target_mem_cgroup = NULL, .nodemask = nodemask, }; struct shrink_control shrink = { @@ -2336,7 +2456,7 @@ unsigned long try_to_free_pages(struct zonelist *zonelist, int order, #ifdef CONFIG_CGROUP_MEM_RES_CTLR -unsigned long mem_cgroup_shrink_node_zone(struct mem_cgroup *mem, +unsigned long mem_cgroup_shrink_node_zone(struct mem_cgroup *memcg, gfp_t gfp_mask, bool noswap, struct zone *zone, unsigned long *nr_scanned) @@ -2348,7 +2468,11 @@ unsigned long mem_cgroup_shrink_node_zone(struct mem_cgroup *mem, .may_unmap = 1, .may_swap = !noswap, .order = 0, - .mem_cgroup = mem, + .target_mem_cgroup = memcg, + }; + struct mem_cgroup_zone mz = { + .mem_cgroup = memcg, + .zone = zone, }; sc.gfp_mask = (gfp_mask & GFP_RECLAIM_MASK) | @@ -2365,7 +2489,7 @@ unsigned long mem_cgroup_shrink_node_zone(struct mem_cgroup *mem, * will pick up pages from other mem cgroup's as well. We hack * the priority and make it zero. */ - shrink_zone(0, zone, &sc); + shrink_mem_cgroup_zone(0, &mz, &sc); trace_mm_vmscan_memcg_softlimit_reclaim_end(sc.nr_reclaimed); @@ -2373,7 +2497,7 @@ unsigned long mem_cgroup_shrink_node_zone(struct mem_cgroup *mem, return sc.nr_reclaimed; } -unsigned long try_to_free_mem_cgroup_pages(struct mem_cgroup *mem_cont, +unsigned long try_to_free_mem_cgroup_pages(struct mem_cgroup *memcg, gfp_t gfp_mask, bool noswap) { @@ -2386,7 +2510,7 @@ unsigned long try_to_free_mem_cgroup_pages(struct mem_cgroup *mem_cont, .may_swap = !noswap, .nr_to_reclaim = SWAP_CLUSTER_MAX, .order = 0, - .mem_cgroup = mem_cont, + .target_mem_cgroup = memcg, .nodemask = NULL, /* we don't care the placement */ .gfp_mask = (gfp_mask & GFP_RECLAIM_MASK) | (GFP_HIGHUSER_MOVABLE & ~GFP_RECLAIM_MASK), @@ -2400,7 +2524,7 @@ unsigned long try_to_free_mem_cgroup_pages(struct mem_cgroup *mem_cont, * take care of from where we get pages. So the node where we start the * scan does not need to be the current node. */ - nid = mem_cgroup_select_victim_node(mem_cont); + nid = mem_cgroup_select_victim_node(memcg); zonelist = NODE_DATA(nid)->node_zonelists; @@ -2416,6 +2540,29 @@ unsigned long try_to_free_mem_cgroup_pages(struct mem_cgroup *mem_cont, } #endif +static void age_active_anon(struct zone *zone, struct scan_control *sc, + int priority) +{ + struct mem_cgroup *memcg; + + if (!total_swap_pages) + return; + + memcg = mem_cgroup_iter(NULL, NULL, NULL); + do { + struct mem_cgroup_zone mz = { + .mem_cgroup = memcg, + .zone = zone, + }; + + if (inactive_anon_is_low(&mz)) + shrink_active_list(SWAP_CLUSTER_MAX, &mz, + sc, priority, 0); + + memcg = mem_cgroup_iter(NULL, memcg, NULL); + } while (memcg); +} + /* * pgdat_balanced is used when checking if a node is balanced for high-order * allocations. Only zones that meet watermarks and are in a zone allowed @@ -2536,7 +2683,7 @@ static unsigned long balance_pgdat(pg_data_t *pgdat, int order, */ .nr_to_reclaim = ULONG_MAX, .order = order, - .mem_cgroup = NULL, + .target_mem_cgroup = NULL, }; struct shrink_control shrink = { .gfp_mask = sc.gfp_mask, @@ -2575,9 +2722,7 @@ loop_again: * Do some background aging of the anon list, to give * pages a chance to be referenced before reclaiming. */ - if (inactive_anon_is_low(zone, &sc)) - shrink_active_list(SWAP_CLUSTER_MAX, zone, - &sc, priority, 0); + age_active_anon(zone, &sc, priority); if (!zone_watermark_ok_safe(zone, order, high_wmark_pages(zone), 0, 0)) { @@ -3353,104 +3498,69 @@ int page_evictable(struct page *page, struct vm_area_struct *vma) return 1; } +#ifdef CONFIG_SHMEM /** - * check_move_unevictable_page - check page for evictability and move to appropriate zone lru list - * @page: page to check evictability and move to appropriate lru list - * @zone: zone page is in - * - * Checks a page for evictability and moves the page to the appropriate - * zone lru list. + * check_move_unevictable_pages - check pages for evictability and move to appropriate zone lru list + * @pages: array of pages to check + * @nr_pages: number of pages to check * - * Restrictions: zone->lru_lock must be held, page must be on LRU and must - * have PageUnevictable set. - */ -static void check_move_unevictable_page(struct page *page, struct zone *zone) -{ - VM_BUG_ON(PageActive(page)); - -retry: - ClearPageUnevictable(page); - if (page_evictable(page, NULL)) { - enum lru_list l = page_lru_base_type(page); - - __dec_zone_state(zone, NR_UNEVICTABLE); - list_move(&page->lru, &zone->lru[l].list); - mem_cgroup_move_lists(page, LRU_UNEVICTABLE, l); - __inc_zone_state(zone, NR_INACTIVE_ANON + l); - __count_vm_event(UNEVICTABLE_PGRESCUED); - } else { - /* - * rotate unevictable list - */ - SetPageUnevictable(page); - list_move(&page->lru, &zone->lru[LRU_UNEVICTABLE].list); - mem_cgroup_rotate_lru_list(page, LRU_UNEVICTABLE); - if (page_evictable(page, NULL)) - goto retry; - } -} - -/** - * scan_mapping_unevictable_pages - scan an address space for evictable pages - * @mapping: struct address_space to scan for evictable pages + * Checks pages for evictability and moves them to the appropriate lru list. * - * Scan all pages in mapping. Check unevictable pages for - * evictability and move them to the appropriate zone lru list. + * This function is only used for SysV IPC SHM_UNLOCK. */ -void scan_mapping_unevictable_pages(struct address_space *mapping) +void check_move_unevictable_pages(struct page **pages, int nr_pages) { - pgoff_t next = 0; - pgoff_t end = (i_size_read(mapping->host) + PAGE_CACHE_SIZE - 1) >> - PAGE_CACHE_SHIFT; - struct zone *zone; - struct pagevec pvec; - - if (mapping->nrpages == 0) - return; - - pagevec_init(&pvec, 0); - while (next < end && - pagevec_lookup(&pvec, mapping, next, PAGEVEC_SIZE)) { - int i; - int pg_scanned = 0; - - zone = NULL; + struct lruvec *lruvec; + struct zone *zone = NULL; + int pgscanned = 0; + int pgrescued = 0; + int i; - for (i = 0; i < pagevec_count(&pvec); i++) { - struct page *page = pvec.pages[i]; - pgoff_t page_index = page->index; - struct zone *pagezone = page_zone(page); + for (i = 0; i < nr_pages; i++) { + struct page *page = pages[i]; + struct zone *pagezone; - pg_scanned++; - if (page_index > next) - next = page_index; - next++; + pgscanned++; + pagezone = page_zone(page); + if (pagezone != zone) { + if (zone) + spin_unlock_irq(&zone->lru_lock); + zone = pagezone; + spin_lock_irq(&zone->lru_lock); + } - if (pagezone != zone) { - if (zone) - spin_unlock_irq(&zone->lru_lock); - zone = pagezone; - spin_lock_irq(&zone->lru_lock); - } + if (!PageLRU(page) || !PageUnevictable(page)) + continue; - if (PageLRU(page) && PageUnevictable(page)) - check_move_unevictable_page(page, zone); + if (page_evictable(page, NULL)) { + enum lru_list lru = page_lru_base_type(page); + + VM_BUG_ON(PageActive(page)); + ClearPageUnevictable(page); + __dec_zone_state(zone, NR_UNEVICTABLE); + lruvec = mem_cgroup_lru_move_lists(zone, page, + LRU_UNEVICTABLE, lru); + list_move(&page->lru, &lruvec->lists[lru]); + __inc_zone_state(zone, NR_INACTIVE_ANON + lru); + pgrescued++; } - if (zone) - spin_unlock_irq(&zone->lru_lock); - pagevec_release(&pvec); - - count_vm_events(UNEVICTABLE_PGSCANNED, pg_scanned); } + if (zone) { + __count_vm_events(UNEVICTABLE_PGRESCUED, pgrescued); + __count_vm_events(UNEVICTABLE_PGSCANNED, pgscanned); + spin_unlock_irq(&zone->lru_lock); + } } +#endif /* CONFIG_SHMEM */ static void warn_scan_unevictable_pages(void) { printk_once(KERN_WARNING - "The scan_unevictable_pages sysctl/node-interface has been " + "%s: The scan_unevictable_pages sysctl/node-interface has been " "disabled for lack of a legitimate use case. If you have " - "one, please send an email to linux-mm@kvack.org.\n"); + "one, please send an email to linux-mm@kvack.org.\n", + current->comm); } /* |