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 D79D2CCFA0D for ; Wed, 5 Nov 2025 21:04:41 +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=0U19jvwafjIOZHkrvh1p72wLiGgKTY6AYcVHnCGRHT8=; b=Faq/KTbp9As8f4nwbq8pE9Fl+J E602yDDPf+Yo7BV3QAIzkU9be5AbIfvCmIWdtueEOK80U9CFIoLYPnqh3Z+Hzo0fd53et6vb3wlB9 StE1xcI3j3zrb9tgzWzGA9Oe0iT5NXnR2IUpeW8m9YY/K5ScEA04kCpNUwonJC9HM5Q6Xx00oVC4i ONptG2g3h9NT9lp12HrJZcugl6Bsb3euV0y4kyOvtnasx+X9Y+6jwgWkvpzqQCFGlWDqCRaEvciZg DVD3p0H77HfgpR7rZv3MTFqc4GR6YDCrbthoDqFbZqzldr4vOTow9y3k3/gMh03Oy/GRQb8/RkUoH Gbg9MkCQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vGkgF-0000000EPqZ-3Qt1; Wed, 05 Nov 2025 21:04:35 +0000 Received: from tor.source.kernel.org ([2600:3c04:e001:324:0:1991:8:25]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1vGkgE-0000000EPpZ-33tX for linux-arm-kernel@lists.infradead.org; Wed, 05 Nov 2025 21:04:34 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by tor.source.kernel.org (Postfix) with ESMTP id B35AD60220; Wed, 5 Nov 2025 21:04:33 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1FFC7C4AF09; Wed, 5 Nov 2025 21:04:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1762376673; bh=ApQa5R07ipGBiVCyA3EgObV++ftyWFoj/ra3rzP5dCY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=cyGGAVyEEtnTJleIGvRPvdX/Cc6KEP2KDLlXtGtmXgRrPqu8Hr6k4dV2PS4NZXG/b 0TuJ9Xv9ZVXQWSh2Q5s5CnahVU/19PTlWf5bvziWhR6igHAhOvKcyNWxStp0IREsuQ dCvjHLJNUd14dOSieLUuFACfi9H0I3xpfHEEvQVGyxubT+iCI4qTrf+SBosWgX9JwY q8wUhQKNtbk77Gb5lvCUyYfdwPpF6f8ZJlnEwEOgiTX7YW4gUFPYiJIdvr5mvwbwxf m8/DbHKO9hBpJpzZlv5oT+4ck92P+ii+pCIyA06mlA6F7sTvBrnc5dZH921cfMjKM3 ISpiuGCwxLlCw== 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 04/31] mm: vmstat: Prepare to protect against concurrent isolated cpuset change Date: Wed, 5 Nov 2025 22:03:20 +0100 Message-ID: <20251105210348.35256-5-frederic@kernel.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20251105210348.35256-1-frederic@kernel.org> References: <20251105210348.35256-1-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 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 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