Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756658Ab3HZMJf (ORCPT ); Mon, 26 Aug 2013 08:09:35 -0400 Received: from merlin.infradead.org ([205.233.59.134]:35463 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751554Ab3HZMJd (ORCPT ); Mon, 26 Aug 2013 08:09:33 -0400 Date: Mon, 26 Aug 2013 14:09:19 +0200 From: Peter Zijlstra To: Paul Turner Cc: Ingo Molnar , Joonsoo Kim , LKML , Mike Galbraith , Alex Shi , Preeti U Murthy , Vincent Guittot , Morten Rasmussen , Namhyung Kim , Lei Wen , Rik van Riel , Joonsoo Kim Subject: Re: [PATCH 09/10] sched, fair: Fix the sd_parent_degenerate() code Message-ID: <20130826120919.GL31370@twins.programming.kicks-ass.net> References: <20130819160058.539049611@infradead.org> <20130819160425.672255367@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2012-12-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1395 Lines: 28 On Sat, Aug 24, 2013 at 03:45:57AM -0700, Paul Turner wrote: > > @@ -5157,6 +5158,13 @@ cpu_attach_domain(struct sched_domain *s > > tmp->parent = parent->parent; > > if (parent->parent) > > parent->parent->child = tmp; > > + /* > > + * Transfer SD_PREFER_SIBLING down in case of a > > + * degenerate parent; the spans match for this > > + * so the property transfers. > > + */ > > + if (parent->flags & SD_PREFER_SIBLING) > > + tmp->flags |= SD_PREFER_SIBLING; > > destroy_sched_domain(parent, cpu); > > } else > > tmp = tmp->parent; > > > > Reviewed-by: Paul Turner BTW, did that comment make sense to you or would you suggest something different? I had/am having a hard time with that comment. Somehow it leaves me wanting. I know I understand the issue now, but I'll doubt the comment will suffice in a years time :/ -- 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/