Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756687Ab1F1KF7 (ORCPT ); Tue, 28 Jun 2011 06:05:59 -0400 Received: from merlin.infradead.org ([205.233.59.134]:38150 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755808Ab1F1KC7 convert rfc822-to-8bit (ORCPT ); Tue, 28 Jun 2011 06:02:59 -0400 Subject: Re: [patch 15/16] sched: return unused runtime on voluntary sleep From: Peter Zijlstra To: Paul Turner Cc: linux-kernel@vger.kernel.org, Bharata B Rao , Dhaval Giani , Balbir Singh , Vaidyanathan Srinivasan , Srivatsa Vaddagiri , Kamalesh Babulal , Hidetoshi Seto , Ingo Molnar , Pavel Emelyanov In-Reply-To: References: <20110621071649.862846205@google.com> <20110621071701.165027089@google.com> <1308842778.1022.136.camel@twins> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT Date: Tue, 28 Jun 2011 12:01:50 +0200 Message-ID: <1309255310.6701.186.camel@twins> Mime-Version: 1.0 X-Mailer: Evolution 2.30.3 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1107 Lines: 25 On Mon, 2011-06-27 at 18:42 -0700, Paul Turner wrote: > - The aesthetics of releasing rq->lock in the put path. Quick > inspection suggests it should actually be safe to do at that point, > and we do similar for idle_balance(). > > Given consideration the above two factors are not requirements, this > could be moved out of a timer and into the put_path directly (with the > fact that we drop rq->lock strongly commented). I have no strong > preference between either choice. Argh, ok I see, distribute_cfs_runtime() wants that. Dropping rq->lock is very fragile esp from the put path, you can only do that _before_ the put path updates rq->curr etc.. So I'd rather you didn't, just keep the timer crap and add some comments there. And we need that distribute_cfs_runtime() muck because that's what unthrottles rqs when more runtime is available.. bah. -- 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/