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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id EB6E5E75453 for ; Wed, 24 Dec 2025 13:47:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=9WbUPE6bJh4bG4sGu5jifyq21X5wZFvvwK42Lk0RJlI=; b=3F3CnKQWxqUTqUqiHOfCzBYIAS YzhPZb2kI8ZWfWmEkFZAC1EX8l36XMrBEUrMnTCj6miws9FejUvI/0YrF/OY9/4TfOqqwh5/uGQAN N1HeGrlKX0/AV/4E6+qP64/ZHTkE43BmjTROJD8z1L2+4AC8otovJiwUWgcMstO/d0FUMDCzTrbqU zV3mYifrwX/GR9K8PsYFVoynxZrUrdQLLfRgqrPBITcH3X00TJoIaFmvIYodqFk1DeDE3gFvGwjF8 I8b6nbzOC1iKjtvgd34AF/E7uTVq2NyRglkF3nWeL3kfQO2YTCW8+dsNdB/JK+CTwmZvY3mmWIqo1 lnxFH6SA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vYPCk-0000000GsLD-1NZy; Wed, 24 Dec 2025 13:47:06 +0000 Received: from tor.source.kernel.org ([172.105.4.254]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1vYPCU-0000000GsEj-0O6y for linux-arm-kernel@lists.infradead.org; Wed, 24 Dec 2025 13:46:54 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by tor.source.kernel.org (Postfix) with ESMTP id 7953960138; Wed, 24 Dec 2025 13:46:49 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3641FC4CEFB; Wed, 24 Dec 2025 13:46:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1766584009; bh=uGe6Ex9InA/ctQyPBwEfQeCRruCOXrYZdOto/ar5f3U=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=QkYBtnhAQ44/QDhvyD+7F9s+u0UyEIzuX1QswgTK4hn9nB5xybx6i1hFP+3OlC5e2 n3QTVokwjBgbk6ivKWOtdU3iSevx+kpxs7OA6i6eJ/CwW1beUG7tm+q8zZ5DLeEHG8 01i13pW9Hf6tjz3oP4mIP6n00eIg3L/gvfs81iaM9AvkPwBHbSLXFuflUzQAcAnLPl gGJgYTg7vHeM+EwQmsb9L+8Agyj9XOWgkiM2t2qaxQzfTm8hMC8yE6gHr4XY3BIac3 uQvrHdBPyTk6U0rXMbbBYsrr5CULeDo3AMXZByb6mc07RYSNfapMAKagVHUaH2F5E7 ZsgsPEuaKJTbQ== 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 09/33] block: Protect against concurrent isolated cpuset change Date: Wed, 24 Dec 2025 14:44:56 +0100 Message-ID: <20251224134520.33231-10-frederic@kernel.org> X-Mailer: git-send-email 2.51.1 In-Reply-To: <20251224134520.33231-1-frederic@kernel.org> References: <20251224134520.33231-1-frederic@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org The block subsystem prevents running the workqueue to isolated CPUs, including those defined by cpuset isolated partitions. Since HK_TYPE_DOMAIN will soon contain both and be subject to runtime modifications, synchronize against housekeeping using the relevant lock. For full support of cpuset changes, the block subsystem may need to propagate changes to isolated cpumask through the workqueue in the future. Signed-off-by: Frederic Weisbecker --- block/blk-mq.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/block/blk-mq.c b/block/blk-mq.c index 1978eef95dca..0037af1216f3 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -4257,12 +4257,16 @@ static void blk_mq_map_swqueue(struct request_queue *q) /* * Rule out isolated CPUs from hctx->cpumask to avoid - * running block kworker on isolated CPUs + * running block kworker on isolated CPUs. + * FIXME: cpuset should propagate further changes to isolated CPUs + * here. */ + rcu_read_lock(); for_each_cpu(cpu, hctx->cpumask) { if (cpu_is_isolated(cpu)) cpumask_clear_cpu(cpu, hctx->cpumask); } + rcu_read_unlock(); /* * Initialize batch roundrobin counts -- 2.51.1