From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755912AbcETNbZ (ORCPT ); Fri, 20 May 2016 09:31:25 -0400 Received: from mail-wm0-f66.google.com ([74.125.82.66]:35770 "EHLO mail-wm0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754140AbcETNbY (ORCPT ); Fri, 20 May 2016 09:31:24 -0400 Date: Fri, 20 May 2016 15:31:21 +0200 From: Michal Hocko To: Vlastimil Babka Cc: David Rientjes , Andrew Morton , Mel Gorman , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [patch] mm, migrate: increment fail count on ENOMEM Message-ID: <20160520133121.GB5215@dhcp22.suse.cz> References: <20160520130649.GB5197@dhcp22.suse.cz> <573F0ED0.4010908@suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <573F0ED0.4010908@suse.cz> User-Agent: Mutt/1.6.0 (2016-04-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri 20-05-16 15:19:12, Vlastimil Babka wrote: > On 05/20/2016 03:06 PM, Michal Hocko wrote: [...] > > Why don't we need also to count also retries? > > We could, but not like you suggest. > > > --- > > diff --git a/mm/migrate.c b/mm/migrate.c > > index 53ab6398e7a2..ef9c5211ae3c 100644 > > --- a/mm/migrate.c > > +++ b/mm/migrate.c > > @@ -1190,9 +1190,9 @@ int migrate_pages(struct list_head *from, new_page_t get_new_page, > > } > > } > > } > > +out: > > nr_failed += retry; > > rc = nr_failed; > > This overwrites rc == -ENOMEM, which at least compaction needs to recognize. > But we could duplicate "nr_failed += retry" in the case -ENOMEM. Right you are. So we should do --- diff --git a/mm/migrate.c b/mm/migrate.c index 53ab6398e7a2..123fed94022b 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -1171,6 +1171,7 @@ int migrate_pages(struct list_head *from, new_page_t get_new_page, switch(rc) { case -ENOMEM: + nr_failed += retry + 1; goto out; case -EAGAIN: retry++; -- Michal Hocko SUSE Labs