From 2443462b0a04ef0f82ad48f4fd0ef4ac5b24c4b7 Mon Sep 17 00:00:00 2001 From: Johannes Weiner Date: Tue, 31 Mar 2009 15:23:12 -0700 Subject: [PATCH] mm: move pagevec stripping to save unlock-relock In shrink_active_list() after the deactivation loop, we strip buffer heads from the potentially remaining pages in the pagevec. Currently, this drops the zone's lru lock for stripping, only to reacquire it again afterwards to update statistics. It is not necessary to strip the pages before updating the stats, so move the whole thing out of the protected region and save the extra locking. Signed-off-by: Johannes Weiner Reviewed-by: MinChan Kim Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/vmscan.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) diff --git a/mm/vmscan.c b/mm/vmscan.c index 51f2df0..988aef9 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -1298,14 +1298,11 @@ static void shrink_active_list(unsigned long nr_pages, struct zone *zone, } __mod_zone_page_state(zone, NR_LRU_BASE + lru, pgmoved); pgdeactivate += pgmoved; - if (buffer_heads_over_limit) { - spin_unlock_irq(&zone->lru_lock); - pagevec_strip(&pvec); - spin_lock_irq(&zone->lru_lock); - } __count_zone_vm_events(PGREFILL, zone, pgscanned); __count_vm_events(PGDEACTIVATE, pgdeactivate); spin_unlock_irq(&zone->lru_lock); + if (buffer_heads_over_limit) + pagevec_strip(&pvec); if (vm_swap_full()) pagevec_swap_free(&pvec); -- 1.8.2.3