From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx161.postini.com [74.125.245.161]) by kanga.kvack.org (Postfix) with SMTP id ADAE46B005A for ; Thu, 23 Aug 2012 12:07:03 -0400 (EDT) Date: Thu, 23 Aug 2012 13:06:48 -0300 From: Rafael Aquini Subject: Re: [PATCH v8 1/5] mm: introduce a common interface for balloon pages mobility Message-ID: <20120823160647.GA10777@t510.redhat.com> References: <20120822093317.GC10680@redhat.com> <20120823021903.GA23660@x61.redhat.com> <20120823100107.GA17409@redhat.com> <20120823121338.GA3062@t510.redhat.com> <20120823123432.GA25659@redhat.com> <20120823130606.GB3746@t510.redhat.com> <20120823135328.GB25709@redhat.com> <20120823152128.GA8975@t510.redhat.com> <20120823155401.GA28876@redhat.com> <50365443.1070104@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <50365443.1070104@redhat.com> Sender: owner-linux-mm@kvack.org List-ID: To: Rik van Riel Cc: "Michael S. Tsirkin" , "Paul E. McKenney" , Peter Zijlstra , linux-mm@kvack.org, linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org, Rusty Russell , Mel Gorman , Andi Kleen , Andrew Morton , Konrad Rzeszutek Wilk , Minchan Kim On Thu, Aug 23, 2012 at 12:03:15PM -0400, Rik van Riel wrote: > > > >Not "longer" - apparently forever unless user resend the leak command. > >It's wrong - it should > >1. not tell host if nothing was done > >2. after migration finished leak and tell host > > Agreed. If the balloon is told to leak N pages, and could > not do so because those pages were locked, the balloon driver > needs to retry (maybe waiting on a page lock?) and not signal > completion until after the job has been completed. > > Having the balloon driver wait on the page lock should be > fine, because compaction does not hold the page lock for > long. And that is precisely what leak_balloon is doing. When it stumbles across a locked page it gets rid of that leak round to give a shot for compaction to finish its task. -- 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