From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 380521CA6B5 for ; Tue, 3 Sep 2024 13:10:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725369056; cv=none; b=HFweanMNFRszn1RZPGkh5CWWhdB3q9kVYyCF+Xuodw3dSbF8CCw/VJQIrL8QSoMq/i/Kk2NNOBIVCygCeqGTJGY1xwRFl4drxUApUte7sD9eV2vYyNd6D6J0OIolKL9FbAaUTKpjXHh+Hr+dBK5mymFnwASPTNzR+0VcT7uRNF0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725369056; c=relaxed/simple; bh=7ljDtEh2yGy7dXUeTwd1MTJ8A6pLBZJjp4bVEZazz5g=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=s55t77nIUi+msxhP0afT0Ce9PZrJcKY0Qt/sdWOZWsYsvCzLDm2RQdC3M/doPMjVezgc/zGX15v/cX/O4gf13wy0K3JJGL/kuboXzubLyxLALC0WzxrDBdxpr9g9SEtJw49oJIJwxu2x0YgH0X7odquUamtZjd29GJZ1WzhTn5M= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Rr4PUu99; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Rr4PUu99" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6CD17C4CEC4; Tue, 3 Sep 2024 13:10:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1725369055; bh=7ljDtEh2yGy7dXUeTwd1MTJ8A6pLBZJjp4bVEZazz5g=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Rr4PUu99oefqkVR4bwmACmnAJIXSgbj4tdibHr5Cn1tCQkBvpllAP1GruUOsmd4sQ wx+TjPlH0a11mKGQUvlVZV/rJgLqO48Bnde9CNGr9hbowvatqxS+Ke1hzkTuQfkjv8 r04IWZrr/t7WsXLZO8L5FpvtnsTihU5LUkXTC+Ys2b+xo8Us1BspGxG8s3a4bC91wF OBGjaCpmawD049eOYD1uJBKw9ANX+h7gGfOspMybY/r2ngeEpOyssR/P70KuE0BCfN S9szgoUWoxLDuAekCvzVPBoFV2jY+hoSFnNIDJ+TtZH203mMgnsMCrD6uWUZbbkmZC YY7HqOEOvDAoQ== Date: Tue, 3 Sep 2024 15:10:53 +0200 From: Frederic Weisbecker To: Waiman Long Cc: Ingo Molnar , Peter Zijlstra , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Valentin Schneider , linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/3] sched/isolation: Add HK_FLAG_SCHED to nohz_full Message-ID: References: <20240818234520.90186-1-longman@redhat.com> <20240818234520.90186-2-longman@redhat.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20240818234520.90186-2-longman@redhat.com> Le Sun, Aug 18, 2024 at 07:45:18PM -0400, Waiman Long a écrit : > The HK_FLAG_SCHED/HK_TYPE_SCHED flag is defined and is also used > in kernel/sched/fair.c since commit de201559df87 ("sched/isolation: > Introduce housekeeping flags"). However, the corresponding cpumask isn't > currently updated anywhere. So the mask is always cpu_possible_mask. > > Add it in nohz_full setup so that nohz_full CPUs will now be removed > from HK_TYPE_SCHED cpumask. > > Signed-off-by: Waiman Long > --- > kernel/sched/isolation.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/kernel/sched/isolation.c b/kernel/sched/isolation.c > index 5891e715f00d..a514994af319 100644 > --- a/kernel/sched/isolation.c > +++ b/kernel/sched/isolation.c > @@ -196,7 +196,7 @@ static int __init housekeeping_nohz_full_setup(char *str) > unsigned long flags; > > flags = HK_FLAG_TICK | HK_FLAG_WQ | HK_FLAG_TIMER | HK_FLAG_RCU | > - HK_FLAG_MISC | HK_FLAG_KTHREAD; > + HK_FLAG_MISC | HK_FLAG_KTHREAD | HK_FLAG_SCHED; > > return housekeeping_setup(str, flags); > } find_new_ilb() already has HK_FLAG_MISC to prevent an isolated CPU from being elected as an ilb. So I think we should simply remove HK_FLAG_SCHED. Thanks.