From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx125.postini.com [74.125.245.125]) by kanga.kvack.org (Postfix) with SMTP id AEC266B005A for ; Fri, 19 Oct 2012 14:33:31 -0400 (EDT) Message-ID: <50819CED.30803@redhat.com> Date: Fri, 19 Oct 2012 14:33:17 -0400 From: Rik van Riel MIME-Version: 1.0 Subject: Re: question on NUMA page migration References: <5081777A.8050104@redhat.com> <1350664742.2768.40.camel@twins> <50818A41.7030909@redhat.com> <1350669236.2768.66.camel@twins> In-Reply-To: <1350669236.2768.66.camel@twins> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Peter Zijlstra Cc: Andrea Arcangeli , Ingo Molnar , Linux Memory Management List , Mel Gorman , Linux kernel Mailing List On 10/19/2012 01:53 PM, Peter Zijlstra wrote: > On Fri, 2012-10-19 at 13:13 -0400, Rik van Riel wrote: >> Another alternative might be to do the put_page inside >> do_prot_none_numa(). That would be analogous to do_wp_page >> disposing of the old page for the caller. > > It'd have to be inside migrate_misplaced_page(), can't do before > isolate_lru_page() or the page might disappear. Doing it after is > (obviously) too late. Keeping an extra refcount on the page might _still_ result in it disappearing from the process by some other means, in-between you grabbing the refcount and invoking migration of the page. >> I am not real happy about NUMA migration introducing its own >> migration mode... > > You didn't seem to mind too much earlier, but I can remove it if you > want. Could have been reviewing fatigue :) And yes, it would have been nice to not have a special migration mode for sched/numa. Speaking of, when do you guys plan to submit a (cleaned up) version of the sched/numa patch series for review on lkml? -- All rights reversed -- 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