From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.3 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id DAC68C2F3A0 for ; Mon, 21 Jan 2019 12:48:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9AD6B2085A for ; Mon, 21 Jan 2019 12:48:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="UqbS6SFn" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728699AbfAUMsA (ORCPT ); Mon, 21 Jan 2019 07:48:00 -0500 Received: from bombadil.infradead.org ([198.137.202.133]:34562 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728490AbfAUMr7 (ORCPT ); Mon, 21 Jan 2019 07:47:59 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=akg9NsvOQxTB9iYhH8J6QqrRyUnPPq1AyWBBeBRuxeM=; b=UqbS6SFn+or342kSXSaiQ2QGw dpz1wIcmX5tsk+ctQEAtlApUjsxzvzu0dzQ5Ct8DusNeBAo2NYn2ScXT4G5iwQf2YjwlzXp84/zEJ LXBbcgpdVXqeS31DBA54304NPtdgwwKwjks03I7WpjtZBvF/tp0LuXrKo+98nXT0bRx7FFENDQVTo eKfr2uHVfrXZLVl6J5TRXjmE5Mc2ssFdhciYD0a+Ktp1IM1P6MlXPWjGvzxaWc/jzdIGP9EFF1Kel +Zg/6XUu0ZqVffr5e6cLmwKa3vh2pGE6oZCYEfRWYnkFsl73VcqhSziza64FSzuBTkWq4jDZLrHjw UTfdXf5GA==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=hirez.programming.kicks-ass.net) by bombadil.infradead.org with esmtpsa (Exim 4.90_1 #2 (Red Hat Linux)) id 1glYza-0008U5-EF; Mon, 21 Jan 2019 12:47:54 +0000 Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 6B0BC20267E54; Mon, 21 Jan 2019 13:47:52 +0100 (CET) Date: Mon, 21 Jan 2019 13:47:52 +0100 From: Peter Zijlstra To: linux-kernel@vger.kernel.org, mingo@kernel.org, vincent.guittot@linaro.org, tglx@linutronix.de, hpa@zytor.com, torvalds@linux-foundation.org Cc: linux-tip-commits@vger.kernel.org, valentin.schneider@arm.com Subject: Re: [tip:sched/core] sched/fair: Fix rounding bug for asym packing Message-ID: <20190121124752.GA17749@hirez.programming.kicks-ass.net> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Sorry guys, I seem to have messed this up :/ Valentin pointed me out that I missed v3 and v4 of these patches; v3 got lost in the x-mas pile and v4 was actually on my todo list for this week, but I'd forgotten I'd already queued v2. I'll go queue delta patches. On Mon, Jan 21, 2019 at 03:33:53AM -0800, tip-bot for Vincent Guittot wrote: > index 50aa2aba69bd..2ccd6e093326 100644 > --- a/kernel/sched/fair.c > +++ b/kernel/sched/fair.c > @@ -8190,6 +8190,12 @@ static inline void update_sg_lb_stats(struct lb_env *env, > /* Adjust by relative CPU capacity of the group */ > sgs->group_capacity = group->sgc->capacity; > sgs->avg_load = (sgs->group_load*SCHED_CAPACITY_SCALE) / sgs->group_capacity; > + /* > + * Prevent division rounding to make the computation of imbalance > + * slightly less than original value and to prevent the rq to be then > + * selected as busiest queue: > + */ > + sgs->avg_load += 1; > > if (sgs->sum_nr_running) > sgs->load_per_task = sgs->sum_weighted_load / sgs->sum_nr_running;