Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758076Ab1FINdg (ORCPT ); Thu, 9 Jun 2011 09:33:36 -0400 Received: from cantor2.suse.de ([195.135.220.15]:40731 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757891Ab1FINdc (ORCPT ); Thu, 9 Jun 2011 09:33:32 -0400 Date: Thu, 9 Jun 2011 14:33:27 +0100 From: Mel Gorman To: Minchan Kim Cc: Andrew Morton , linux-mm , LKML , KOSAKI Motohiro , Andrea Arcangeli , Rik van Riel , Johannes Weiner , KAMEZAWA Hiroyuki Subject: Re: [PATCH v3 01/10] compaction: trivial clean up acct_isolated Message-ID: <20110609133327.GT5247@suse.de> References: <71a79768ff8ef356db09493dbb5d6c390e176e0d.1307455422.git.minchan.kim@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: <71a79768ff8ef356db09493dbb5d6c390e176e0d.1307455422.git.minchan.kim@gmail.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2973 Lines: 71 On Tue, Jun 07, 2011 at 11:38:14PM +0900, Minchan Kim wrote: > acct_isolated of compaction uses page_lru_base_type which returns only > base type of LRU list so it never returns LRU_ACTIVE_ANON or LRU_ACTIVE_FILE. > In addtion, cc->nr_[anon|file] is used in only acct_isolated so it doesn't have > fields in conpact_control. > This patch removes fields from compact_control and makes clear function of > acct_issolated which counts the number of anon|file pages isolated. > > Cc: KOSAKI Motohiro > Cc: Mel Gorman > Cc: Andrea Arcangeli > Acked-by: Rik van Riel > Acked-by: Johannes Weiner > Reviewed-by: KAMEZAWA Hiroyuki > Signed-off-by: Minchan Kim > --- > mm/compaction.c | 18 +++++------------- > 1 files changed, 5 insertions(+), 13 deletions(-) > > diff --git a/mm/compaction.c b/mm/compaction.c > index 021a296..61eab88 100644 > --- a/mm/compaction.c > +++ b/mm/compaction.c > @@ -35,10 +35,6 @@ struct compact_control { > unsigned long migrate_pfn; /* isolate_migratepages search base */ > bool sync; /* Synchronous migration */ > > - /* Account for isolated anon and file pages */ > - unsigned long nr_anon; > - unsigned long nr_file; > - > unsigned int order; /* order a direct compactor needs */ > int migratetype; /* MOVABLE, RECLAIMABLE etc */ > struct zone *zone; > @@ -212,17 +208,13 @@ static void isolate_freepages(struct zone *zone, > static void acct_isolated(struct zone *zone, struct compact_control *cc) > { > struct page *page; > - unsigned int count[NR_LRU_LISTS] = { 0, }; > + unsigned int count[2] = { 0, }; > > - list_for_each_entry(page, &cc->migratepages, lru) { > - int lru = page_lru_base_type(page); > - count[lru]++; > - } > + list_for_each_entry(page, &cc->migratepages, lru) > + count[!!page_is_file_cache(page)]++; > > - cc->nr_anon = count[LRU_ACTIVE_ANON] + count[LRU_INACTIVE_ANON]; > - cc->nr_file = count[LRU_ACTIVE_FILE] + count[LRU_INACTIVE_FILE]; > - __mod_zone_page_state(zone, NR_ISOLATED_ANON, cc->nr_anon); > - __mod_zone_page_state(zone, NR_ISOLATED_FILE, cc->nr_file); > + __mod_zone_page_state(zone, NR_ISOLATED_ANON, count[0]); > + __mod_zone_page_state(zone, NR_ISOLATED_FILE, count[1]); You are hard-coding assumptions about the value of LRU_INACTIVE_ANON and LRU_INACTIVE_FILE here. I have no expectation that these will change but who knows for sure? To be robust against unexpected changes, count should still be NR_LRU_LISTS and you should use the LRU_INACTIVE_ANON and LRU_INACTIVE_FILE values. I agree that summing LRU_ACTIVE_* is silly. -- Mel Gorman SUSE Labs -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/