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 4ECBB309DBD; Mon, 13 Oct 2025 20:32:29 +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=1760387549; cv=none; b=FP4GI77U+VDJ3YF9q3lY/nWv+zPbZK2hOYN27U2XWY2gBOjdRsP2qy6R33yd9TrmJCRO6fMwmVPUJfF01V27NnRFNwl/nGv3gyJzLRSH1jqRWIc5jxLmtl0Fan1VCZmYP8zVI1xb0JyozPMQi1gTKa274KdET1QMA6iUsY4Zhws= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760387549; c=relaxed/simple; bh=j3Yn5NfIqiY+L8eK9Vhd8gsEecPCt7Wufp6RLuexjXk=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=d3WR4+eRu9FsSHqzNXYSvn41byNvfZjXX8eGsL4t+krNOQEV2HJnh/SH7Li64uSZcyDMJeyHWPTFPTXU+YwbIf9ErcYHB5pa4XJzRFubzVUAPWlKseBHJZlGxu2r88iFaK2csKIVrGdthdNN4j0iyz13ZpC0jJ5xBb4jiTpXLyQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=E9QIBiXi; 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="E9QIBiXi" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1DF1BC4CEFE; Mon, 13 Oct 2025 20:32:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1760387548; bh=j3Yn5NfIqiY+L8eK9Vhd8gsEecPCt7Wufp6RLuexjXk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=E9QIBiXidYsZWsu1jAbV5EpCQbVgypRg6OIyTAb8uAKJP5F/YAKJvhjAfNlvkxDjW awaI/15P+xNEsT0NmFWdETXLffdy/5VaLpBO+YuXJsuJToTfLbFxHxR6dAoijF67md QK/rRPUUSF7rF/ey5AbbxbDn8n4O+o20A/9fGxfVCOBlR8AR3UG+IawKTys2dgVT58 zJDnygaDk2Ds1Bhdc+XOJEzvN4u444CFho1+rpg3teYAsFo5vo/4N8ZLTLRDLXjW4S +EcIwRduhsS6CUfrWGbJhLmqHwvOepcsLlrue71vdu8IfPkkex48lCiRrlhh9fpMpi 8rpXiyrMupMzA== From: Frederic Weisbecker To: LKML Cc: Frederic Weisbecker , =?UTF-8?q?Michal=20Koutn=C3=BD?= , Andrew Morton , Bjorn Helgaas , Catalin Marinas , 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: Mon, 13 Oct 2025 22:31:17 +0200 Message-ID: <20251013203146.10162-5-frederic@kernel.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20251013203146.10162-1-frederic@kernel.org> References: <20251013203146.10162-1-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 modifyable 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 bb09c032eecf..7afb2981501f 100644 --- a/mm/vmstat.c +++ b/mm/vmstat.c @@ -2135,11 +2135,13 @@ 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(); } -- 2.51.0