From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753543AbaCKQ2u (ORCPT ); Tue, 11 Mar 2014 12:28:50 -0400 Received: from cantor2.suse.de ([195.135.220.15]:58857 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752669AbaCKQ2t (ORCPT ); Tue, 11 Mar 2014 12:28:49 -0400 Date: Tue, 11 Mar 2014 16:28:45 +0000 From: Mel Gorman To: Rik van Riel , Sasha Levin Cc: David Rientjes , Andrew Morton , "linux-mm@kvack.org" , LKML , hhuang@redhat.com, knoel@redhat.com, aarcange@redhat.com Subject: Re: [PATCH -mm] mm,numa,mprotect: always continue after finding a stable thp page Message-ID: <20140311162845.GA30604@suse.de> References: <5318E4BC.50301@oracle.com> <20140306173137.6a23a0b2@cuia.bos.redhat.com> <5318FC3F.4080204@redhat.com> <20140307140650.GA1931@suse.de> <20140307150923.GB1931@suse.de> <20140307182745.GD1931@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: <20140307182745.GD1931@suse.de> 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 On Fri, Mar 07, 2014 at 06:27:45PM +0000, Mel Gorman wrote: > > This is a completely untested prototype. It rechecks pmd_trans_huge > > under the lock and falls through if it hit a parallel split. It's not > > perfect because it could decide to fall through just because there was > > no prot_numa work to do but it's for illustration purposes. Secondly, > > I noted that you are calling invalidate for every pmd range. Is that not > > a lot of invalidations? We could do the same by just tracking the address > > of the first invalidation. > > > > And there were other minor issues. This is still untested but Sasha, > can you try it out please? I discussed this with Rik on IRC for a bit and > reckon this should be sufficient if the correct race has been identified. > Any luck with this patch Sasha? It passed basic tests here but I had not seen the issue trigger either. -- Mel Gorman SUSE Labs