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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C72E9C7619A for ; Wed, 12 Apr 2023 12:52:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229626AbjDLMwe (ORCPT ); Wed, 12 Apr 2023 08:52:34 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40992 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230345AbjDLMwY (ORCPT ); Wed, 12 Apr 2023 08:52:24 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1FBCC93F4 for ; Wed, 12 Apr 2023 05:51:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.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; bh=oybkbka4fOpt3xY41p981UiNKAAComubQyhE6dbXvgM=; b=QgbidjcWe2Lf65qkdM3ZstxFlp 1TKvO3E3Jswv8snN9rK1PcnMlLDSZKCLL6mu0JuR8xZW6l8OvgpGBxucirCC+Bq9mGcBzEc/XeG00 GOBVze6QCGk8CAEpmwzaDWhfXxCDD0Z8bvrqJTmqoJbnNXpuEg3ZCsP+gptobdtrUYhbgU5M7pNRb HoXPjTmRTN87+vHPB4Saebp5PL7dRV2Ymsxdq3LIIA3V53uy8lS5HDBbR186VndHJbibP8vI7sY3U qVQj7FDURee7zwr03lC3BVWorm+fA1YkQ6i5oxKa0Igs3DN9JwHf9Ihid5zIBs1+t15w9lKXxC6Dy ff9TQk/w==; Received: from j130084.upc-j.chello.nl ([24.132.130.84] helo=noisy.programming.kicks-ass.net) by casper.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1pmZvw-006sGW-8s; Wed, 12 Apr 2023 12:50:44 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id 87FEB300274; Wed, 12 Apr 2023 14:50:43 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 6A894235CC4A1; Wed, 12 Apr 2023 14:50:43 +0200 (CEST) Date: Wed, 12 Apr 2023 14:50:43 +0200 From: Peter Zijlstra To: Vincent Guittot Cc: mingo@redhat.com, juri.lelli@redhat.com, dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de, bristot@redhat.com, vschneid@redhat.com, linux-kernel@vger.kernel.org, tjcao980311@gmail.com Subject: Re: [PATCH] sched/fair: fix imbalance overflow Message-ID: <20230412125043.GG628377@hirez.programming.kicks-ass.net> References: <20230411090611.627225-1-vincent.guittot@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230411090611.627225-1-vincent.guittot@linaro.org> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Apr 11, 2023 at 11:06:11AM +0200, Vincent Guittot wrote: > When local group is fully busy but its average load is above system load, > computing the imbalance will overflow and local group is not the best > target for pulling this load. > > Fixes: 0b0695f2b34a ("sched/fair: Rework load_balance()") > Reported-by: Tingjia Cao > Link: https://lore.kernel.org/lkml/CABcWv9_DAhVBOq2=W=2ypKE9dKM5s2DvoV8-U0+GDwwuKZ89jQ@mail.gmail.com/T/ > Signed-off-by: Vincent Guittot > --- Thanks, added Tested-by Tingjia per his reply.