From 1489fa14cb757b496c8fa2b63097dbcee6690695 Mon Sep 17 00:00:00 2001 From: Mel Gorman Date: Mon, 9 Aug 2010 17:19:33 -0700 Subject: [PATCH] vmscan: update isolated page counters outside of main path in shrink_inactive_list() When shrink_inactive_list() isolates pages, it updates a number of counters using temporary variables to gather them. These consume stack and it's in the main path that calls ->writepage(). This patch moves the accounting updates outside of the main path to reduce stack usage. Signed-off-by: Mel Gorman Reviewed-by: Johannes Weiner Acked-by: Rik van Riel Cc: Dave Chinner Cc: Chris Mason Cc: Nick Piggin Cc: Rik van Riel Cc: Johannes Weiner Cc: Christoph Hellwig Cc: KAMEZAWA Hiroyuki Cc: KOSAKI Motohiro Cc: Andrea Arcangeli Cc: Michael Rubin Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/vmscan.c | 63 +++++++++++++++++++++++++++++++++++++------------------------ 1 file changed, 38 insertions(+), 25 deletions(-) diff --git a/mm/vmscan.c b/mm/vmscan.c index 512f463..1c3d960 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -1076,7 +1076,8 @@ static unsigned long clear_active_flags(struct list_head *page_list, ClearPageActive(page); nr_active++; } - count[lru]++; + if (count) + count[lru]++; } return nr_active; @@ -1156,12 +1157,13 @@ static int too_many_isolated(struct zone *zone, int file, * TODO: Try merging with migrations version of putback_lru_pages */ static noinline_for_stack void -putback_lru_pages(struct zone *zone, struct zone_reclaim_stat *reclaim_stat, +putback_lru_pages(struct zone *zone, struct scan_control *sc, unsigned long nr_anon, unsigned long nr_file, 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); @@ -1200,6 +1202,37 @@ putback_lru_pages(struct zone *zone, struct zone_reclaim_stat *reclaim_stat, pagevec_release(&pvec); } +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) +{ + unsigned long nr_active; + unsigned int count[NR_LRU_LISTS] = { 0, }; + struct zone_reclaim_stat *reclaim_stat = get_reclaim_stat(zone, sc); + + nr_active = clear_active_flags(isolated_list, count); + __count_vm_events(PGDEACTIVATE, nr_active); + + __mod_zone_page_state(zone, NR_ACTIVE_FILE, + -count[LRU_ACTIVE_FILE]); + __mod_zone_page_state(zone, NR_INACTIVE_FILE, + -count[LRU_INACTIVE_FILE]); + __mod_zone_page_state(zone, NR_ACTIVE_ANON, + -count[LRU_ACTIVE_ANON]); + __mod_zone_page_state(zone, NR_INACTIVE_ANON, + -count[LRU_INACTIVE_ANON]); + + *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; +} + /* * shrink_inactive_list() is a helper for shrink_zone(). It returns the number * of reclaimed pages @@ -1211,10 +1244,8 @@ shrink_inactive_list(unsigned long nr_to_scan, struct zone *zone, LIST_HEAD(page_list); unsigned long nr_scanned; unsigned long nr_reclaimed = 0; - struct zone_reclaim_stat *reclaim_stat = get_reclaim_stat(zone, sc); unsigned long nr_taken; unsigned long nr_active; - unsigned int count[NR_LRU_LISTS] = { 0, }; unsigned long nr_anon; unsigned long nr_file; @@ -1261,25 +1292,7 @@ shrink_inactive_list(unsigned long nr_to_scan, struct zone *zone, return 0; } - nr_active = clear_active_flags(&page_list, count); - __count_vm_events(PGDEACTIVATE, nr_active); - - __mod_zone_page_state(zone, NR_ACTIVE_FILE, - -count[LRU_ACTIVE_FILE]); - __mod_zone_page_state(zone, NR_INACTIVE_FILE, - -count[LRU_INACTIVE_FILE]); - __mod_zone_page_state(zone, NR_ACTIVE_ANON, - -count[LRU_ACTIVE_ANON]); - __mod_zone_page_state(zone, NR_INACTIVE_ANON, - -count[LRU_INACTIVE_ANON]); - - 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; + update_isolated_counts(zone, sc, &nr_anon, &nr_file, &page_list); spin_unlock_irq(&zone->lru_lock); @@ -1299,7 +1312,7 @@ shrink_inactive_list(unsigned long nr_to_scan, struct zone *zone, * The attempt at page out may have made some * of the pages active, mark them inactive again. */ - nr_active = clear_active_flags(&page_list, count); + nr_active = clear_active_flags(&page_list, NULL); count_vm_events(PGDEACTIVATE, nr_active); nr_reclaimed += shrink_page_list(&page_list, sc, PAGEOUT_IO_SYNC); @@ -1310,7 +1323,7 @@ shrink_inactive_list(unsigned long nr_to_scan, struct zone *zone, __count_vm_events(KSWAPD_STEAL, nr_reclaimed); __count_zone_vm_events(PGSTEAL, zone, nr_reclaimed); - putback_lru_pages(zone, reclaim_stat, nr_anon, nr_file, &page_list); + putback_lru_pages(zone, sc, nr_anon, nr_file, &page_list); return nr_reclaimed; } -- 2.7.4