From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mta0.migadu.com (out-141.mta0.migadu.com [91.218.175.141]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1569538F651 for ; Fri, 11 Sep 2026 08:02:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.141 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789113752; cv=none; b=tSlAD/GWfOfQ1RiPJoUCJycL5qGu5ua+bMF7wopy3M9BE2YeCl/zKTp17utPD3S09aXYHBVYPofSs2+RbuwenLK+NsZHHxn0AXcTt8mu8FmPXa9tedYVbXaN5qAlWNoA5Mcdi3aeeZGEyPlj5AV4WDdg7IwdUWIMvHTIU4xdxIs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789113752; c=relaxed/simple; bh=DT3XFpe3pacIAc5YAypwgMYEhUAkDdTmk92G+6zy28I=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=KccLpeY+HmCWgaho8TQJTchBh5dsCZfCjJ5HWgO1Jv5WZc3amg9dquWaIByVNkic8JiI1sKDZnUxcXU7doM4Fr0RFVr4V3hH/qc0bn2WE/n3wMnplf5jfW1QgA2Z53l+/RiJitraeVPSD3n1xVIXJU0Fb6VSh83J6csX4owrDW8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=unUKJ8DY; arc=none smtp.client-ip=91.218.175.141 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="unUKJ8DY" X-Envelope-To: linux-kernel@vger.kernel.org DKIM-Signature: a=rsa-sha256; bh=DT3XFpe3pacIAc5YAypwgMYEhUAkDdTmk92G+6zy28I=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1789113749; v=1; x=1789718549; b=unUKJ8DYrcQ4bToz8c2edIi7z+fgZhzlq1fTA7zcUDp3SrYNjC6l4l89K6tSEwzP26gkF9BA URNdaFCPlvukjlJrwvIeVQ+HyByePZMThMsMxspzIvf69MdBtNQFx1nyOB9sP1cyAIOx9WzbW/q +x0B4Ox/jB+evgHktfLHQOOQ= X-Envelope-To: linux-kernel@vger.kernel.org Received: by smtp.migadu.com with ESMTPS id 7ddc78a39b3151cc; Fri, 11 Sep 2026 08:02:28 +0000 X-Mizu-Trace-ID: 7ddc78a39b3151cc X-Migadu-Flow: FLOW_OUT From: Ye Liu To: Andrew Morton Cc: Ye Liu , Michal Hocko , Lorenzo Stoakes , Gregory Price , SJ Park , peterz@infradead.org, paulmck@kernel.org, mingo@redhat.com, rostedt@goodmis.org, jpoimboe@kernel.org, mic@digikod.net, oleg@redhat.com, tglx@kernel.org, david@kernel.org, linmiaohe@huawei.com, nao.horiguchi@gmail.com, rafael@kernel.org, gnoack3000@gmail.com, rientjes@google.com, shakeel.butt@linux.dev, xu.xin16@zte.com.cn, chengming.zhou@linux.dev, will@kernel.org, boqun@kernel.org, frederic@kernel.org, neeraj.upadhyay@kernel.org, joelagnelf@nvidia.com, josh@joshtriplett.org, urezki@gmail.com, juri.lelli@redhat.com, vincent.guittot@linaro.org, tony.luck@intel.com, reinette.chatre@intel.com, x86@kernel.org, paul@paul-moore.com, jmorris@namei.org, serge@hallyn.com, pavel@kernel.org, lance.yang@linux.dev, mhiramat@kernel.org, pmladek@suse.com, longman@redhat.com, mathieu.desnoyers@efficios.com, jiangshanlai@gmail.com, qiang.zhang@linux.dev, dietmar.eggemann@arm.com, bsegall@google.com, mgorman@suse.de, vschneid@redhat.com, kprateek.nayak@amd.com, mark.rutland@arm.com, Dave.Martin@arm.com, james.morse@arm.com, babu.moger@amd.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, rcu@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-security-module@vger.kernel.org Subject: [PATCH v3 14/15] lib: convert process iterator to for_each_process_rculock Date: Fri, 11 Sep 2026 15:57:59 +0800 Message-Id: <20260911075800.491472-15-ye.liu@linux.dev> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20260911075800.491472-1-ye.liu@linux.dev> References: <20260911075800.491472-1-ye.liu@linux.dev> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Ye Liu Replace the manual rcu_read_lock()/rcu_read_unlock() pair combined with for_each_process() loop in lib/ with for_each_process_rculock(), which scopes the RCU read lock to the loop body via scoped_guard(rcu). No functional change. Signed-off-by: Ye Liu Acked-by: Michal Hocko Reviewed-by: Lorenzo Stoakes (ARM) Reviewed-by: Gregory Price (Meta) Reviewed-by: SJ Park --- Changes in v2: - Rename *_rcu to *_rculock lib/is_single_threaded.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) diff --git a/lib/is_single_threaded.c b/lib/is_single_threaded.c index 8c98b20bfc41..4e7fe85454ab 100644 --- a/lib/is_single_threaded.c +++ b/lib/is_single_threaded.c @@ -26,8 +26,7 @@ bool current_is_single_threaded(void) return true; ret = false; - rcu_read_lock(); - for_each_process(p) { + for_each_process_rculock(p) { if (unlikely(p->flags & PF_KTHREAD)) continue; if (unlikely(p == task->group_leader)) @@ -48,7 +47,5 @@ bool current_is_single_threaded(void) } ret = true; found: - rcu_read_unlock(); - return ret; } -- 2.25.1