Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753049AbbHTVLm (ORCPT ); Thu, 20 Aug 2015 17:11:42 -0400 Received: from casper.infradead.org ([85.118.1.10]:32913 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752047AbbHTVLl (ORCPT ); Thu, 20 Aug 2015 17:11:41 -0400 Date: Thu, 20 Aug 2015 23:11:31 +0200 From: Peter Zijlstra To: Byungchul Park Cc: mingo@kernel.org, linux-kernel@vger.kernel.org, yuyang.du@intel.com Subject: Re: [PATCH v3 0/5] sync a se with its cfs_rq when att(det)aching it Message-ID: <20150820211131.GC3161@worktop.event.rightround.com> References: <1439966836-11266-1-git-send-email-byungchul.park@lge.com> <20150820011721.GA3138@worktop.event.rightround.com> <20150820083841.GH24261@byungchulpark-X58A-UD3R> <20150820104609.GI24261@byungchulpark-X58A-UD3R> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20150820104609.GI24261@byungchulpark-X58A-UD3R> User-Agent: Mutt/1.5.22.1 (2013-10-16) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1470 Lines: 38 On Thu, Aug 20, 2015 at 07:46:09PM +0900, Byungchul Park wrote: > On Thu, Aug 20, 2015 at 05:38:41PM +0900, Byungchul Park wrote: > > On Thu, Aug 20, 2015 at 03:17:21AM +0200, Peter Zijlstra wrote: > > > > > > I did something like this on top.. please have a look at the XXX and > > > integrate. > > > > i am not sure, what do you intend for me to do. > > > > do you mean that i am supposed to integrate this cleanup patch you gave me > > including the XXX comment? No, the intent was for you to think about the point marked XXX, which you've done below. > > > + * > > > + * XXX this appears wrong!! check history, > > > + * we appear to always set queued and RUNNING under the same lock instance > > > + * might be from before TASK_WAKING ? > > > */ > > > > is it impossible to happen to check if vruntime is normalized, when doing > > something like e.g. active load balance where queued != TASK_ON_RQ_QUEUED > > and p->state == TASK_RUNNING? > > furthermore, in any migration by load balance, it seems to be possible.. > > > > > i think it can happen.. OK, then we need to change the comment to reflect the actual reason the test is needed. Because I think the currently described scenario is incorrect. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/