Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754014AbcDEQvN (ORCPT ); Tue, 5 Apr 2016 12:51:13 -0400 Received: from mail-wm0-f52.google.com ([74.125.82.52]:35347 "EHLO mail-wm0-f52.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753022AbcDEQvK (ORCPT ); Tue, 5 Apr 2016 12:51:10 -0400 Date: Tue, 5 Apr 2016 18:50:59 +0200 From: luca abeni To: Peter Zijlstra Cc: linux-kernel@vger.kernel.org, Ingo Molnar , Juri Lelli Subject: Re: [RFC v2 2/7] Correctly track the active utilisation for migrating tasks Message-ID: <20160405185059.3195ab87@utopia> In-Reply-To: <20160405122425.GV3430@twins.programming.kicks-ass.net> References: <1459523553-29089-1-git-send-email-luca.abeni@unitn.it> <1459523553-29089-3-git-send-email-luca.abeni@unitn.it> <20160405122425.GV3430@twins.programming.kicks-ass.net> X-Mailer: Claws Mail 3.12.0 (GTK+ 2.24.28; i686-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 910 Lines: 28 On Tue, 5 Apr 2016 14:24:25 +0200 Peter Zijlstra wrote: [...] > > @@ -1618,7 +1620,9 @@ static void pull_dl_task(struct rq *this_rq) > > resched = true; > > > > deactivate_task(src_rq, p, 0); > > + sub_running_bw(&p->dl, &src_rq->dl); > > set_task_cpu(p, this_cpu); > > + add_running_bw(&p->dl, &this_rq->dl); > > activate_task(this_rq, p, 0); > > dmin = p->dl.deadline; > > > > Are these the only places a DL task might be migrated from? In > particular I worry about the case where we assign an existing DL task to > a different cpuset. I was under the impression that these (+ the select_task_rq_dl() thing) covered all of the migration cases... But I was probably wrong: now that you say this, I realise that I never tested moving dl tasks between different cpusets. I'll test that, and fix the patch if some new issue appears. Thanks, Luca