From 3f79768f239746d19accd88da96263ef35d6a219 Mon Sep 17 00:00:00 2001 From: Hugh Dickins Date: Thu, 12 Jan 2012 17:20:07 -0800 Subject: [PATCH] mm: rearrange putback_inactive_pages There is sometimes confusion between the global putback_lru_pages() in migrate.c and the static putback_lru_pages() in vmscan.c: rename the latter putback_inactive_pages(): it helps shrink_inactive_list() rather as move_active_pages_to_lru() helps shrink_active_list(). Remove unused scan_control arg from putback_inactive_pages() and from update_isolated_counts(). Move clear_active_flags() inside update_isolated_counts(). Move NR_ISOLATED accounting up into shrink_inactive_list() itself, so the balance is clearer. Do the spin_lock_irq() before calling putback_inactive_pages() and spin_unlock_irq() after return from it, so that it better matches update_isolated_counts() and move_active_pages_to_lru(). Signed-off-by: Hugh Dickins Cc: Johannes Weiner Cc: KOSAKI Motohiro Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/vmscan.c | 96 ++++++++++++++++++++++++----------------------------- 1 file changed, 44 insertions(+), 52 deletions(-) diff --git a/mm/vmscan.c b/mm/vmscan.c index 9aab5dc51718..2880396f7953 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -1284,32 +1284,6 @@ static unsigned long isolate_lru_pages(unsigned long nr_to_scan, return nr_taken; } -/* - * 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 @@ -1383,26 +1357,21 @@ 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 mem_cgroup_zone *mz, 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; - LIST_HEAD(pages_to_free); - struct zone *zone = mz->zone; 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))) { @@ -1432,26 +1401,40 @@ putback_lru_pages(struct mem_cgroup_zone *mz, struct scan_control *sc, 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); - free_hot_cold_page_list(&pages_to_free, 1); + /* + * 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 mem_cgroup_zone *mz, - struct scan_control *sc, + struct list_head *page_list, unsigned long *nr_anon, - unsigned long *nr_file, - struct list_head *isolated_list) + 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(mz); + 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, @@ -1465,8 +1448,6 @@ update_isolated_counts(struct mem_cgroup_zone *mz, *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; @@ -1571,7 +1552,10 @@ shrink_inactive_list(unsigned long nr_to_scan, struct mem_cgroup_zone *mz, return 0; } - update_isolated_counts(mz, 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); @@ -1585,12 +1569,20 @@ shrink_inactive_list(unsigned long nr_to_scan, struct mem_cgroup_zone *mz, 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(mz, 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 -- 2.30.2