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Wysocki" , Andrew Morton , Ingo Molnar , Will Deacon , Boqun Feng , "Paul E. McKenney" , Frederic Weisbecker , Neeraj Upadhyay , Joel Fernandes , Josh Triplett , Uladzislau Rezki , Juri Lelli , Vincent Guittot , Steven Rostedt , Masami Hiramatsu , Josh Poimboeuf , Ye Liu , Michal Hocko , mic@digikod.net, david@kernel.org, linmiaohe@huawei.com, nao.horiguchi@gmail.com, gnoack3000@gmail.com, ljs@kernel.org, sj@kernel.org, rientjes@google.com, shakeel.butt@linux.dev, xu.xin16@zte.com.cn, chengming.zhou@linux.dev, 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, 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 5/8] kernel: convert process/thread iterators to for_each_*_rculock Message-ID: References: <20260907081334.1152889-1-ye.liu@linux.dev> <20260907081334.1152889-6-ye.liu@linux.dev> MIME-Version: 1.0 In-Reply-To: X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.93 X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: 2ktPKm0bnK3bikdY2q_piwHeF8jaFSAvmsJH0uCSIQo_1788803856 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=us-ascii Content-Disposition: inline X-Stat-Signature: ghbhkd4sh7j3r8zxky98i1qziosob476 X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: 0E5E7100009 X-Rspam-User: X-HE-Tag: 1788803866-576693 X-HE-Meta: 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 0CHWgMyY Bamy182xw43wTDpKHpY7dotm0hYdjvX5hLMmwi1+gN/wFQtKxd6KtvGcUtz9rRa71tCea9yCXPKyDMhtk4H+4+LiEZRVb5HZHOXKODj6oeXu+9qmEhwSHER8NV59KDJlgh0A/hgik0RYOcEzQnNycoL74Zrkn/kTzUVqyi1VQ3ihpBAzGr4bYoKqeta0CtjwjQyh4eSCw2tL7KOZPpjUg20Kk+43w0COVzsvIS3BczMov5fl0eyd9X6a0Nn68ViCwGM0prwKqcgyys0UON8et55q1ZbKyK+PrWreOpqPXRUu8g/+D0e/PDqgizqH8sHaINUUdlBydX9465VY8jhfpWr9YrbwKPujXCEIURRsfFixnDRLgUaFrfJMOrewVzly7rphuqjxs8lu4ZBl9JMUKG752vUQqXXQ6o4T3cF5Kk8zkCC0bLL9g+fytZPBr8aX/LZxTd1SR+knthvKDGAqtFa6+LSrRTZ/QpCIZ Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 09/07, Gregory Price wrote: > > On Mon, Sep 07, 2026 at 04:13:31PM +0800, Ye Liu wrote: > > --- a/kernel/hung_task.c > > +++ b/kernel/hung_task.c > > @@ -315,13 +315,12 @@ static void check_hung_uninterruptible_tasks(unsigned long timeout) > > return; > > > > this_round_count = 0; > > - rcu_read_lock(); > > - for_each_process_thread(g, t) { > > + for_each_process_thread_rculock(g, t) { > > if (!max_count--) > > - goto unlock; > > + goto out; > ... snip ... > > - unlock: > > - rcu_read_unlock(); > > - > > +out: > > if (!this_round_count) > > return; > > > > The sunken rcu_read_lock()/unlock() + scoped_guard usage makes this goto > at a minimum very confusing, if not actually broken. I am afraid I misunderstood you concerns... This patch renames the "unlock:" label to "out:", and to me this makes sense. Unfortunately for_each_process_thread() and the new helper can't use "break". Oleg.