From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 46BA84477F3; Mon, 7 Sep 2026 12:27:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788784041; cv=none; b=itPOInjcJFq/fdwcsNa6+mkrfxv8cE+SKatnogNXgAOLdxIHwVPgLU0gsVsloLD0ia8nlN3c61HhH0JvIozFOtJgpX4NNM/hVXje/k4Bm5TmHoVQlnKiDPjwWRmWK2B+TPQlp9VDZV9kHJZDXvVt+wCH1E0d1ZVyNvsltmP58u0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788784041; c=relaxed/simple; bh=4KhMUWrVeTM3TUi3xbt6hV73HS/X/W7s3ec217rpnDo=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=HQqIJGFICdQQWygMiK/HHKzQWKETk6kdHoVBHN3TEru+ZWJ/tZ3kp8w97+wUJ8/zzH07YTLe/jtAszo0G+lW6Ji0igyeXKuqUT2UL7z8fckYJauhfJsIPg2rbwFMyVChl2miieqJ788PtARIbkB19Hgay0stdH2f0hD+knroI98= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=hBJkmeHo; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="hBJkmeHo" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8107A1F00A3A; Mon, 7 Sep 2026 12:27:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788784039; bh=FON6q6qStRwddcTjTo4OO7kzte1WdlEtk70KYE6DEZc=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=hBJkmeHoo3adk3zkUC7eYlw8h/TJyFQC7PnBfhei3eMbML+nMpxFUdoab8vEGHrC8 qv1TOSO6hpNr8vp5zd2I50DVcVBN2gbGEAaCVwtfnjCLuQaAOdZeOlXR/p7+Z4JKeP 9TN2uOi8STQr/J/OHftEHtUR0UvWj+6PFSAan524lD3d6akZQ7EehNCueclrUrGHOR 8ejbl/+TwuNme7llFf+Fy/j3D1/HZyvT3e7tKvC0GorCTf0v4LFtXuURtE7JiUbqv4 nlEE6828TnKP1RT6mAXgU/uOPKyk9IkmccHdH3cVzbR9hDg5I7E6j9AKneb4a6l/SN 0ymItKMeX+E/w== Date: Mon, 7 Sep 2026 13:27:03 +0100 From: "Lorenzo Stoakes (ARM)" To: Ye Liu Cc: Tony Luck , Reinette Chatre , x86@kernel.org, Christian Brauner , Andrew Morton , Jann Horn , "Mike Rapoport (Microsoft)" , "David Hildenbrand (arm)" , Alexey Dobriyan , Oleg Nesterov , Ye Liu , Michal Hocko , peterz@infradead.org, paulmck@kernel.org, mingo@redhat.com, rostedt@goodmis.org, jpoimboe@kernel.org, mic@digikod.net, tglx@kernel.org, linmiaohe@huawei.com, nao.horiguchi@gmail.com, rafael@kernel.org, gnoack3000@gmail.com, sj@kernel.org, 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, 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: Re: [PATCH v2 6/8] fs: convert process/thread iterators to for_each_*_rculock Message-ID: References: <20260907081334.1152889-1-ye.liu@linux.dev> <20260907081334.1152889-7-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-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260907081334.1152889-7-ye.liu@linux.dev> On Mon, Sep 07, 2026 at 04:13:32PM +0800, Ye Liu wrote: > From: Ye Liu > > Replace the manual rcu_read_lock()/rcu_read_unlock() pairs combined > with for_each_process() and for_each_process_thread() loops in fs/ > with the for_each_*_rculock() macros, which scope the RCU read lock > to the loop body via scoped_guard(rcu). > > No functional change. > > Signed-off-by: Ye Liu > Acked-by: Michal Hocko LGTM so: Reviewed-by: Lorenzo Stoakes (ARM) > --- > Changes in v2: > - Rename *_rcu to *_rculock > fs/proc/base.c | 4 +--- > fs/resctrl/rdtgroup.c | 8 ++------ > 2 files changed, 3 insertions(+), 9 deletions(-) > > diff --git a/fs/proc/base.c b/fs/proc/base.c > index 6a39de424f62..3de4f4557e4c 100644 > --- a/fs/proc/base.c > +++ b/fs/proc/base.c > @@ -1160,8 +1160,7 @@ static int __set_oom_adj(struct file *file, int oom_adj, bool legacy) > if (mm) { > struct task_struct *p; > > - rcu_read_lock(); > - for_each_process(p) { > + for_each_process_rculock(p) { > if (same_thread_group(task, p)) > continue; > > @@ -1177,7 +1176,6 @@ static int __set_oom_adj(struct file *file, int oom_adj, bool legacy) > } > task_unlock(p); > } > - rcu_read_unlock(); > mmdrop(mm); > } > err_unlock: > diff --git a/fs/resctrl/rdtgroup.c b/fs/resctrl/rdtgroup.c > index 5dcbb0a964e8..b14df8b23f1a 100644 > --- a/fs/resctrl/rdtgroup.c > +++ b/fs/resctrl/rdtgroup.c > @@ -709,14 +709,12 @@ int rdtgroup_tasks_assigned(struct rdtgroup *r) > > lockdep_assert_held(&rdtgroup_mutex); > > - rcu_read_lock(); > - for_each_process_thread(p, t) { > + for_each_process_thread_rculock(p, t) { > if (is_closid_match(t, r) || is_rmid_match(t, r)) { > ret = 1; > break; > } > } > - rcu_read_unlock(); > > return ret; > } > @@ -826,15 +824,13 @@ static void show_rdt_tasks(struct rdtgroup *r, struct seq_file *s) > struct task_struct *p, *t; > pid_t pid; > > - rcu_read_lock(); > - for_each_process_thread(p, t) { > + for_each_process_thread_rculock(p, t) { > if (is_closid_match(t, r) || is_rmid_match(t, r)) { > pid = task_pid_vnr(t); > if (pid) > seq_printf(s, "%d\n", pid); > } > } > - rcu_read_unlock(); > } > > static int rdtgroup_tasks_show(struct kernfs_open_file *of, > -- > 2.25.1 > -- Cheers, Lorenzo