From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754961AbaCKRWF (ORCPT ); Tue, 11 Mar 2014 13:22:05 -0400 Received: from mx1.redhat.com ([209.132.183.28]:30300 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752395AbaCKRWD (ORCPT ); Tue, 11 Mar 2014 13:22:03 -0400 Message-ID: <531F4128.8020109@redhat.com> Date: Tue, 11 Mar 2014 13:00:24 -0400 From: Rik van Riel User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.1.0 MIME-Version: 1.0 To: Sasha Levin , Mel Gorman 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 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> <20140311162845.GA30604@suse.de> <531F3F15.8050206@oracle.com> In-Reply-To: <531F3F15.8050206@oracle.com> Content-Type: text/plain; charset=ISO-8859-15; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 03/11/2014 12:51 PM, Sasha Levin wrote: > On 03/11/2014 12:28 PM, Mel Gorman wrote: >> 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. >> > > Sorry, I've been stuck in my weekend project of getting lockdep to work > with page locks :) > > It takes a moment to test, so just to be sure - I should have only this > last patch applied? > Without the one in the original mail? Indeed, only this patch should do it.