From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752077AbcGROud (ORCPT ); Mon, 18 Jul 2016 10:50:33 -0400 Received: from outbound-smtp03.blacknight.com ([81.17.249.16]:35461 "EHLO outbound-smtp03.blacknight.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751503AbcGROu3 (ORCPT ); Mon, 18 Jul 2016 10:50:29 -0400 From: Mel Gorman To: Andrew Morton Cc: Johannes Weiner , Minchan Kim , Vlastimil Babka , Linux-MM , LKML , Mel Gorman Subject: [PATCH 2/3] mm, vmscan: Release/reacquire lru_lock on pgdat change Date: Mon, 18 Jul 2016 15:50:25 +0100 Message-Id: <1468853426-12858-3-git-send-email-mgorman@techsingularity.net> X-Mailer: git-send-email 2.6.4 In-Reply-To: <1468853426-12858-1-git-send-email-mgorman@techsingularity.net> References: <1468853426-12858-1-git-send-email-mgorman@techsingularity.net> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org With node-lru, the locking is based on the pgdat. As Minchan pointed out, there is an opportunity to reduce LRU lock release/acquire in check_move_unevictable_pages by only changing lock on a pgdat change. Signed-off-by: Mel Gorman --- mm/vmscan.c | 22 +++++++++++----------- 1 file changed, 11 insertions(+), 11 deletions(-) diff --git a/mm/vmscan.c b/mm/vmscan.c index 45344acf52ba..a6f31617a08c 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -3775,24 +3775,24 @@ int page_evictable(struct page *page) void check_move_unevictable_pages(struct page **pages, int nr_pages) { struct lruvec *lruvec; - struct zone *zone = NULL; + struct pglist_data *pgdat = NULL; int pgscanned = 0; int pgrescued = 0; int i; for (i = 0; i < nr_pages; i++) { struct page *page = pages[i]; - struct zone *pagezone; + struct pglist_data *pagepgdat = page_pgdat(page); pgscanned++; - pagezone = page_zone(page); - if (pagezone != zone) { - if (zone) - spin_unlock_irq(zone_lru_lock(zone)); - zone = pagezone; - spin_lock_irq(zone_lru_lock(zone)); + pagepgdat = page_pgdat(page); + if (pagepgdat != pgdat) { + if (pgdat) + spin_unlock_irq(&pgdat->lru_lock); + pgdat = pagepgdat; + spin_lock_irq(&pgdat->lru_lock); } - lruvec = mem_cgroup_page_lruvec(page, zone->zone_pgdat); + lruvec = mem_cgroup_page_lruvec(page, pgdat); if (!PageLRU(page) || !PageUnevictable(page)) continue; @@ -3808,10 +3808,10 @@ void check_move_unevictable_pages(struct page **pages, int nr_pages) } } - if (zone) { + if (pgdat) { __count_vm_events(UNEVICTABLE_PGRESCUED, pgrescued); __count_vm_events(UNEVICTABLE_PGSCANNED, pgscanned); - spin_unlock_irq(zone_lru_lock(zone)); + spin_unlock_irq(&pgdat->lru_lock); } } #endif /* CONFIG_SHMEM */ -- 2.6.4