From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756406AbbCRNsh (ORCPT ); Wed, 18 Mar 2015 09:48:37 -0400 Received: from cantor2.suse.de ([195.135.220.15]:56762 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756235AbbCRNsf (ORCPT ); Wed, 18 Mar 2015 09:48:35 -0400 Message-ID: <55098230.5080600@suse.cz> Date: Wed, 18 Mar 2015 14:48:32 +0100 From: Vlastimil Babka User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.5.0 MIME-Version: 1.0 To: Konstantin Khlebnikov , linux-mm@kvack.org CC: Roman Gushchin , Andrew Morton , Johannes Weiner , linux-kernel@vger.kernel.org, Mel Gorman , Michal Hocko Subject: Re: [PATCH RFC] mm: reset pages_scanned only when free pages are above high watermark References: <20150311183023.4476.40069.stgit@buzz> In-Reply-To: <20150311183023.4476.40069.stgit@buzz> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 03/11/2015 07:30 PM, Konstantin Khlebnikov wrote: > Technically, this counter works as OOM-countdown. Let's reset it only > when zone is completely recovered and ready to handle any allocations. > Otherwise system could never recover and stuck in livelock. > > Signed-off-by: Konstantin Khlebnikov Hmm, could this help in cases like this one? https://lkml.org/lkml/2015/1/23/688 > --- > mm/page_alloc.c | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > index ffd5ad2a6e10..ef7795c8c121 100644 > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -701,7 +701,8 @@ static void free_pcppages_bulk(struct zone *zone, int count, > > spin_lock(&zone->lock); > nr_scanned = zone_page_state(zone, NR_PAGES_SCANNED); > - if (nr_scanned) > + if (nr_scanned && > + zone_page_state(zone, NR_FREE_PAGES) > high_wmark_pages(zone)) > __mod_zone_page_state(zone, NR_PAGES_SCANNED, -nr_scanned); > > while (to_free) { > @@ -752,7 +753,8 @@ static void free_one_page(struct zone *zone, > unsigned long nr_scanned; > spin_lock(&zone->lock); > nr_scanned = zone_page_state(zone, NR_PAGES_SCANNED); > - if (nr_scanned) > + if (nr_scanned && > + zone_page_state(zone, NR_FREE_PAGES) > high_wmark_pages(zone)) > __mod_zone_page_state(zone, NR_PAGES_SCANNED, -nr_scanned); > > if (unlikely(has_isolate_pageblock(zone) || > > -- > 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/ . > Don't email: email@kvack.org >