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 CB6012512FF; Thu, 1 Jan 2026 22:14:45 +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=1767305685; cv=none; b=XKU/A4F6iB9BFokXMLT6DYxkB78dM+qLq2JsjM6CcT4gVPcUY6FymKJUhADDbdzJAwBBDqS40C75NmE9WBTuy2H4rVOnRwkmg4M5lTT9VZjggslOF0WPpMU/9jaIslmrsuawtfFIZpj8ncUXaP7QCN9VQrGyX165N1VCZGNhhB4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767305685; c=relaxed/simple; bh=gBHkj0y4jQxeMV2qzbEciSScfrXq1yZennkNx/2Itiw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=hBFDRB6a7Kqds6GO74aU1qihKRDCGhSJWypjD2KBb+wGViarKrp5CtCtG4HbC+TGJmFR0Gz0rFlbKoi3HucAwV4tDjeh+kHRLYQHWW2xUTlUidVoeTuc3ooycH6WxdFI6wPw9DyjcXnHj4K/xnZOPgUEOz//y1FVO703XSl+qQg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=eUUVJ4Ql; 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="eUUVJ4Ql" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8E32CC4CEF7; Thu, 1 Jan 2026 22:14:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1767305685; bh=gBHkj0y4jQxeMV2qzbEciSScfrXq1yZennkNx/2Itiw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=eUUVJ4QlV2Ud1CrS6GjbiF6v46hq34xCiNh0ZJVjVwX1TXlPBFeyAEgU8UViw5n7D i59CAEMxlUC3VxC9iEwmbmBwuKfcfVzPUUaZD6pH8UiyBaJnaMjvHjrcuuVjuwPRY/ 88byT+kZctItQI+QgXaYFZ8RmSFVhJsjKDttq+hwL8Wx0ETwMm6W1gzDxv7AULKKam YJnAGrRKYx/MpQRZJU91JeeCHIxHJewdUxbzC9D5Z/RjPXLAk6MIhhlLqAIn3gDP0V HcXzQ3FppfamhiEne7w0DLSThz/ucPmLuVjZrVFub7h2zTJg0+6DD93qqzEmXwyKQN Z4zpqik3l7rJg== From: Frederic Weisbecker To: LKML Cc: Frederic Weisbecker , =?UTF-8?q?Michal=20Koutn=C3=BD?= , Andrew Morton , Bjorn Helgaas , Catalin Marinas , Chen Ridong , Danilo Krummrich , "David S . Miller" , Eric Dumazet , Gabriele Monaco , Greg Kroah-Hartman , Ingo Molnar , Jakub Kicinski , Jens Axboe , Johannes Weiner , Lai Jiangshan , Marco Crivellari , Michal Hocko , Muchun Song , Paolo Abeni , Peter Zijlstra , Phil Auld , "Rafael J . Wysocki" , Roman Gushchin , Shakeel Butt , Simon Horman , Tejun Heo , Thomas Gleixner , Vlastimil Babka , Waiman Long , Will Deacon , cgroups@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-block@vger.kernel.org, linux-mm@kvack.org, linux-pci@vger.kernel.org, netdev@vger.kernel.org Subject: [PATCH 04/33] mm: vmstat: Prepare to protect against concurrent isolated cpuset change Date: Thu, 1 Jan 2026 23:13:29 +0100 Message-ID: <20260101221359.22298-5-frederic@kernel.org> X-Mailer: git-send-email 2.51.1 In-Reply-To: <20260101221359.22298-1-frederic@kernel.org> References: <20260101221359.22298-1-frederic@kernel.org> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit The HK_TYPE_DOMAIN housekeeping cpumask will soon be made modifiable at runtime. In order to synchronize against vmstat workqueue to make sure that no asynchronous vmstat work is pending or executing on a newly made isolated CPU, target and queue a vmstat work under the same RCU read side critical section. Whenever housekeeping will update the HK_TYPE_DOMAIN cpumask, a vmstat workqueue flush will also be issued in a further change to make sure that no work remains pending after a CPU has been made isolated. Signed-off-by: Frederic Weisbecker --- mm/vmstat.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/mm/vmstat.c b/mm/vmstat.c index 65de88cdf40e..ed19c0d42de6 100644 --- a/mm/vmstat.c +++ b/mm/vmstat.c @@ -2144,11 +2144,13 @@ static void vmstat_shepherd(struct work_struct *w) * infrastructure ever noticing. Skip regular flushing from vmstat_shepherd * for all isolated CPUs to avoid interference with the isolated workload. */ - if (cpu_is_isolated(cpu)) - continue; + scoped_guard(rcu) { + if (cpu_is_isolated(cpu)) + continue; - if (!delayed_work_pending(dw) && need_update(cpu)) - queue_delayed_work_on(cpu, mm_percpu_wq, dw, 0); + if (!delayed_work_pending(dw) && need_update(cpu)) + queue_delayed_work_on(cpu, mm_percpu_wq, dw, 0); + } cond_resched(); } -- 2.51.1