From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail138.messagelabs.com (mail138.messagelabs.com [216.82.249.35]) by kanga.kvack.org (Postfix) with ESMTP id 2BE7A6B007E for ; Tue, 7 Jun 2011 10:39:11 -0400 (EDT) Received: by mail-pz0-f41.google.com with SMTP id 4so3156114pzk.14 for ; Tue, 07 Jun 2011 07:39:09 -0700 (PDT) From: Minchan Kim Subject: [PATCH v3 04/10] compaction: make isolate_lru_page with filter aware Date: Tue, 7 Jun 2011 23:38:17 +0900 Message-Id: <10ad16e14fdbe47ac36f7e55ae72ed59ae73ed0c.1307455422.git.minchan.kim@gmail.com> In-Reply-To: References: In-Reply-To: References: Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: linux-mm , LKML , KOSAKI Motohiro , Mel Gorman , Andrea Arcangeli , Rik van Riel , Johannes Weiner , KAMEZAWA Hiroyuki , Minchan Kim In async mode, compaction doesn't migrate dirty or writeback pages. So, it's meaningless to pick the page and re-add it to lru list. Of course, when we isolate the page in compaction, the page might be dirty or writeback but when we try to migrate the page, the page would be not dirty, writeback. So it could be migrated. But it's very unlikely as isolate and migration cycle is much faster than writeout. So, this patch helps cpu and prevent unnecessary LRU churning. Cc: Andrea Arcangeli Reviewed-by: KAMEZAWA Hiroyuki Reviewed-by: KOSAKI Motohiro Acked-by: Johannes Weiner Acked-by: Mel Gorman Acked-by: Rik van Riel Signed-off-by: Minchan Kim --- mm/compaction.c | 7 +++++-- 1 files changed, 5 insertions(+), 2 deletions(-) diff --git a/mm/compaction.c b/mm/compaction.c index f0d75e9..8079346 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -243,6 +243,7 @@ static unsigned long isolate_migratepages(struct zone *zone, unsigned long last_pageblock_nr = 0, pageblock_nr; unsigned long nr_scanned = 0, nr_isolated = 0; struct list_head *migratelist = &cc->migratepages; + enum ISOLATE_MODE mode = ISOLATE_ACTIVE|ISOLATE_INACTIVE; /* Do not scan outside zone boundaries */ low_pfn = max(cc->migrate_pfn, zone->zone_start_pfn); @@ -326,9 +327,11 @@ static unsigned long isolate_migratepages(struct zone *zone, continue; } + if (!cc->sync) + mode |= ISOLATE_CLEAN; + /* Try isolate the page */ - if (__isolate_lru_page(page, - ISOLATE_ACTIVE|ISOLATE_INACTIVE, 0) != 0) + if (__isolate_lru_page(page, mode, 0) != 0) continue; VM_BUG_ON(PageTransCompound(page)); -- 1.7.0.4 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org