From 666356297ec4e9e6594c6008803f2b1403ff7950 Mon Sep 17 00:00:00 2001 From: Mel Gorman Date: Mon, 9 Aug 2010 17:19:30 -0700 Subject: [PATCH] vmscan: set up pagevec as late as possible in shrink_inactive_list() shrink_inactive_list() sets up a pagevec to release unfreeable pages. It uses significant amounts of stack doing this. This patch splits shrink_inactive_list() to take the stack usage out of the main path so that callers to writepage() do not contain an unused pagevec on the stack. 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 | 99 ++++++++++++++++++++++++++++++----------------------- 1 file changed, 56 insertions(+), 43 deletions(-) diff --git a/mm/vmscan.c b/mm/vmscan.c index 7f25f336551..12b692164bc 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -1132,20 +1132,66 @@ 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 zone_reclaim_stat *reclaim_stat, + unsigned long nr_anon, unsigned long nr_file, + struct list_head *page_list) +{ + struct page *page; + struct pagevec pvec; + + pagevec_init(&pvec, 1); + + /* + * Put back any unfreeable pages. + */ + spin_lock(&zone->lru_lock); + while (!list_empty(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))) { + spin_unlock_irq(&zone->lru_lock); + putback_lru_page(page); + spin_lock_irq(&zone->lru_lock); + continue; + } + SetPageLRU(page); + lru = page_lru(page); + add_page_to_lru_list(zone, page, lru); + if (is_active_lru(lru)) { + int file = is_file_lru(lru); + reclaim_stat->recent_rotated[file]++; + } + if (!pagevec_add(&pvec, page)) { + spin_unlock_irq(&zone->lru_lock); + __pagevec_release(&pvec); + spin_lock_irq(&zone->lru_lock); + } + } + __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); +} + /* * shrink_inactive_list() is a helper for shrink_zone(). It returns the number * of reclaimed pages */ -static unsigned long shrink_inactive_list(unsigned long nr_to_scan, - struct zone *zone, struct scan_control *sc, - int priority, int file) +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) { LIST_HEAD(page_list); - struct pagevec pvec; unsigned long nr_scanned; unsigned long nr_reclaimed = 0; struct zone_reclaim_stat *reclaim_stat = get_reclaim_stat(zone, sc); - struct page *page; unsigned long nr_taken; unsigned long nr_active; unsigned int count[NR_LRU_LISTS] = { 0, }; @@ -1161,8 +1207,6 @@ static unsigned long shrink_inactive_list(unsigned long nr_to_scan, } - pagevec_init(&pvec, 1); - lru_add_drain(); spin_lock_irq(&zone->lru_lock); @@ -1192,8 +1236,10 @@ static unsigned long shrink_inactive_list(unsigned long nr_to_scan, */ } - if (nr_taken == 0) - goto done; + if (nr_taken == 0) { + spin_unlock_irq(&zone->lru_lock); + return 0; + } nr_active = clear_active_flags(&page_list, count); __count_vm_events(PGDEACTIVATE, nr_active); @@ -1244,40 +1290,7 @@ static unsigned long shrink_inactive_list(unsigned long nr_to_scan, __count_vm_events(KSWAPD_STEAL, nr_reclaimed); __count_zone_vm_events(PGSTEAL, zone, nr_reclaimed); - spin_lock(&zone->lru_lock); - /* - * Put back any unfreeable pages. - */ - while (!list_empty(&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))) { - spin_unlock_irq(&zone->lru_lock); - putback_lru_page(page); - spin_lock_irq(&zone->lru_lock); - continue; - } - SetPageLRU(page); - lru = page_lru(page); - add_page_to_lru_list(zone, page, lru); - if (is_active_lru(lru)) { - int file = is_file_lru(lru); - reclaim_stat->recent_rotated[file]++; - } - if (!pagevec_add(&pvec, page)) { - spin_unlock_irq(&zone->lru_lock); - __pagevec_release(&pvec); - spin_lock_irq(&zone->lru_lock); - } - } - __mod_zone_page_state(zone, NR_ISOLATED_ANON, -nr_anon); - __mod_zone_page_state(zone, NR_ISOLATED_FILE, -nr_file); - -done: - spin_unlock_irq(&zone->lru_lock); - pagevec_release(&pvec); + putback_lru_pages(zone, reclaim_stat, nr_anon, nr_file, &page_list); return nr_reclaimed; } -- 2.20.1