Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753234Ab1FLOzg (ORCPT ); Sun, 12 Jun 2011 10:55:36 -0400 Received: from cantor.suse.de ([195.135.220.2]:34172 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751254Ab1FLOze (ORCPT ); Sun, 12 Jun 2011 10:55:34 -0400 Date: Sun, 12 Jun 2011 16:55:31 +0200 From: Michal Hocko To: Minchan Kim Cc: Andrew Morton , linux-mm , LKML , KOSAKI Motohiro , Mel Gorman , Andrea Arcangeli , Rik van Riel , Johannes Weiner , KAMEZAWA Hiroyuki Subject: Re: [PATCH v3 05/10] vmscan: make isolate_lru_page with filter aware Message-ID: <20110612145531.GD24323@tiehlicka.suse.cz> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: 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: 3218 Lines: 96 On Tue 07-06-11 23:38:18, Minchan Kim wrote: > In __zone_reclaim case, we don't want to shrink mapped page. > Nonetheless, we have isolated mapped page and re-add it into > LRU's head. It's unnecessary CPU overhead and makes LRU churning. > > Of course, when we isolate the page, the page might be mapped but > when we try to migrate the page, the page would be not mapped. > So it could be migrated. But race is rare and although it happens, > it's no big deal. Same like with the previous patch. I think it would be better to introduce ISOLATE_UNMAPPED here. Other than that looks good to me Reviewed-by: Michal Hocko > > Cc: KOSAKI Motohiro > Cc: Mel Gorman > Cc: Rik van Riel > Cc: Andrea Arcangeli > Reviewed-by: KAMEZAWA Hiroyuki > Acked-by: Johannes Weiner > Signed-off-by: Minchan Kim > --- > mm/vmscan.c | 17 +++++++++++++++-- > 1 files changed, 15 insertions(+), 2 deletions(-) > > diff --git a/mm/vmscan.c b/mm/vmscan.c > index 26aa627..c08911d 100644 > --- a/mm/vmscan.c > +++ b/mm/vmscan.c > @@ -1408,6 +1408,12 @@ shrink_inactive_list(unsigned long nr_to_scan, struct zone *zone, > reclaim_mode |= ISOLATE_ACTIVE; > > lru_add_drain(); > + > + if (!sc->may_unmap) > + reclaim_mode |= ISOLATE_UNMAPPED; > + if (!sc->may_writepage) > + reclaim_mode |= ISOLATE_CLEAN; > + > spin_lock_irq(&zone->lru_lock); > > if (scanning_global_lru(sc)) { > @@ -1525,19 +1531,26 @@ static void shrink_active_list(unsigned long nr_pages, struct zone *zone, > struct page *page; > struct zone_reclaim_stat *reclaim_stat = get_reclaim_stat(zone, sc); > unsigned long nr_rotated = 0; > + enum ISOLATE_MODE reclaim_mode = ISOLATE_ACTIVE; > > lru_add_drain(); > + > + if (!sc->may_unmap) > + reclaim_mode |= ISOLATE_UNMAPPED; > + if (!sc->may_writepage) > + reclaim_mode |= ISOLATE_CLEAN; > + > spin_lock_irq(&zone->lru_lock); > if (scanning_global_lru(sc)) { > nr_taken = isolate_pages_global(nr_pages, &l_hold, > &pgscanned, sc->order, > - ISOLATE_ACTIVE, zone, > + reclaim_mode, zone, > 1, file); > zone->pages_scanned += pgscanned; > } else { > nr_taken = mem_cgroup_isolate_pages(nr_pages, &l_hold, > &pgscanned, sc->order, > - ISOLATE_ACTIVE, zone, > + reclaim_mode, zone, > sc->mem_cgroup, 1, file); > /* > * mem_cgroup_isolate_pages() keeps track of > -- > 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 -- Michal Hocko SUSE Labs SUSE LINUX s.r.o. Lihovarska 1060/12 190 00 Praha 9 Czech Republic -- 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/