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 291DD3793AF; Thu, 5 Mar 2026 13:54:26 +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=1772718867; cv=none; b=Lcg3LJ+5lCSdiF8w+03Z2e1l01idKe/9nyd4VOVTpaJKC0GzAZii6tuslQdYa8BE6UNoDGbDZBAXdVODYwg9MvU0CAly8cimuYnSXIEssL+P/2mEg4iOpi64bT4ydp37wjmm+dpUaNMYGPmu+AHDAt/sWheoQkGch7dbEXCaLKY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772718867; c=relaxed/simple; bh=Fx7+iHNtLQjDbqKjz59eFIh4No8kY4RANvdg2ZZSJXk=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=SzkA4tZKx+Ho2uHfQ8vHYYOEznczV9qRJv4+1zMYRTZqslacqndRBswF3ePmAxDt6b6fBNq+upFKyupdN7rq/8ct+hoc9Rtmw56pwehkbiBHkCKG0LmqQbDHSJ9V5KXjybfgF9wrPJ6Tp22ylKwDFmnSb0UoAxmSzzuYfjWfIm4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=SxzSw4Qz; 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="SxzSw4Qz" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 72EEDC19423; Thu, 5 Mar 2026 13:54:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772718866; bh=Fx7+iHNtLQjDbqKjz59eFIh4No8kY4RANvdg2ZZSJXk=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=SxzSw4QzrVDLRtERJx2EAO/mrjnK6Ymp/AFDvabXz5Q1G9y48jfQq1N8l732ck5y+ 7/CncmtUtLQ6zsRpINu/7mQPrxcZGu9nA/GmGfChz8KTZk6xBSzIM5o0t7Y5HoZWeQ +07LatnSf0hqWLJab7gUWdihrKHw/pqmkKzT0HPQ2fomf61HqMwapuO/7q2rvdw/XY oZOjMhrW+FXyeYim2+tR0elXRbyRitzUJ76mHZNiZ3yh8b0nRfnxYrITfQuzIsYfVd OCZkkA5t/KEyGxmAOkYpQ1V3wI9f89ccY44yVhVpsMn1BehWybyiOPaB8ZtmUmj+kN xzeM+q0xP7f9w== Date: Thu, 5 Mar 2026 14:54:23 +0100 From: Frederic Weisbecker To: Waiman Long Cc: Chen Ridong , Tejun Heo , Johannes Weiner , Michal =?iso-8859-1?Q?Koutn=FD?= , cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, Jon Hunter Subject: Re: [PATCH] cgroup/cpuset: Call rebuild_sched_domains() directly in hotplug Message-ID: References: <20260304184100.71015-1-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: <20260304184100.71015-1-longman@redhat.com> Le Wed, Mar 04, 2026 at 01:41:00PM -0500, Waiman Long a écrit : > Besides deferring the call to housekeeping_update(), commit 6df415aa46ec > ("cgroup/cpuset: Defer housekeeping_update() calls from CPU hotplug > to workqueue") also defers the rebuild_sched_domains() call to > the workqueue. So a new offline CPU may still be in a sched domain > or new online CPU not showing up in the sched domains for a short > transition period. That could be a problem in some corner cases and > can be the cause of a reported test failure[1]. Fix it by calling > rebuild_sched_domains_cpuslocked() directly in hotplug as before. If > isolated partition invalidation or recreation is being done, the > housekeeping_update() call to update the housekeeping cpumasks will > still be deferred to a workqueue. > > In commit 3bfe47967191 ("cgroup/cpuset: Move > housekeeping_update()/rebuild_sched_domains() together"), > housekeeping_update() is called before rebuild_sched_domains() because > it needs to access the HK_TYPE_DOMAIN housekeeping cpumask. That is now > changed to use the static HK_TYPE_DOMAIN_BOOT cpumask as HK_TYPE_DOMAIN > cpumask is now changeable at run time. As a result, we can move the But rebuild_sched_domains() will still handle the cpuset isolated partitions somehow right? Sorry for the question, I'm a bit lost in the partition_sched_domains() maze... -- Frederic Weisbecker SUSE Labs