From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1031215AbcDMOXC (ORCPT ); Wed, 13 Apr 2016 10:23:02 -0400 Received: from mx2.suse.de ([195.135.220.15]:35398 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S964849AbcDMOXB (ORCPT ); Wed, 13 Apr 2016 10:23:01 -0400 Message-ID: <1460557378.11954.22.camel@suse.de> Subject: Re: sched: tweak select_idle_sibling to look for idle threads From: Mike Galbraith To: Chris Mason Cc: Peter Zijlstra , Ingo Molnar , Matt Fleming , linux-kernel@vger.kernel.org Date: Wed, 13 Apr 2016 16:22:58 +0200 In-Reply-To: <20160413134430.3s2w4dodocgislpb@floor.thefacebook.com> References: <20160409190554.honue3gtian2p6vr@floor.thefacebook.com> <1460282661.4251.44.camel@suse.de> <20160410195543.fp2tpixaafsts5x3@floor.thefacebook.com> <1460350461.3870.36.camel@suse.de> <20160412003044.smr24xzuom3locvo@floor.thefacebook.com> <1460436248.3839.80.camel@suse.de> <20160412132758.7apgqqwl2c2wksy6@floor.thefacebook.com> <1460484977.5617.32.camel@suse.de> <20160412200728.GA41928@clm-mbp.thefacebook.com> <1460517531.3780.29.camel@suse.de> <20160413134430.3s2w4dodocgislpb@floor.thefacebook.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.16.5 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 2016-04-13 at 09:44 -0400, Chris Mason wrote: > So you're interested in numbers where we pass the wake_wide decision > into select_idle_sibling(), and then use that instead of (or in addition > to?) my should_scan_idle() function? Yeah, I was thinking instead of, and hoping that would be enough. > I agree we may need to tweak wake_wide, since most of our wakeups now > are failed affine wakeups. What exactly do you mean by failed affine wakeups? Failed because wake_wide() said we don't want one, or because wake_affine() said we can't have one? If the later, my thought bubble may have just burst, but it still "feels" right. -Mike