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Mon, 21 Sep 2026 09:23:08 +0000 X-Mizu-Trace-ID: 515370f5e6daff6a X-Migadu-Flow: FLOW_OUT From: Ye Liu To: Andrew Morton Cc: Ye Liu , Michal Hocko , SJ Park , Lorenzo Stoakes , Oleg Nesterov , peterz@infradead.org, paulmck@kernel.org, mingo@redhat.com, rostedt@goodmis.org, jpoimboe@kernel.org, mic@digikod.net, tglx@kernel.org, david@kernel.org, linmiaohe@huawei.com, nao.horiguchi@gmail.com, rafael@kernel.org, gnoack3000@gmail.com, gourry@gourry.net, 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, 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 Subject: [PATCH v4 07/15] hung_task: convert process/thread iterators to for_each_*_rculock Date: Mon, 21 Sep 2026 17:20:53 +0800 Message-Id: <20260921092101.89285-8-ye.liu@linux.dev> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20260921092101.89285-1-ye.liu@linux.dev> References: <20260921092101.89285-1-ye.liu@linux.dev> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: AADC740004 X-Stat-Signature: 7npjch6e7o6cn9yjdwi4t8ck4uahe75k X-Rspam-User: X-HE-Tag: 1789982589-337717 X-HE-Meta: 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 aLSaDdT+ HrGPfIgElA7AaQs8xc1FhSq9akr+JuBm2f7QeWp97+/ukrPvWBFlme0p1dxrz59PKfNsZGS7uHYder6tJC5ojOJJh3m5qEvcUz4+J8SX6Fo2FhkwCC96UvQOsNhAU+nBR/EL3+encl1Z0j8bxGYpLpOr3JaPHCc1F4VxO1pIaMCoVNNBLLlbyI46MJ/91TOWgRT18By6cBgyBGLL8aJBDfPdABjNCiRotZuDpWQjHHrZFQw3uZOldghvkKKkOVw8DiltkwChiLvWEPs1lVj/mjQkWWZCL9OELyxGFbQp6Lk3YuuBoHUwtAblzFdRXx3cK+k2THv+Q7N2d/8jYTD2ZcgfJ0XccO5jggmq32sIR5w6VfbtmQjiobuVHAxcNGJCEsvbPqZR7/hTkyIzgg6Wm/usVe9xPzulZGsScK9ZZD7Z3y2ITQk5DrGxI+B9tKWvrsPEh1DDPb3stmeo= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: From: Ye Liu Replace the manual rcu_read_lock()/rcu_read_unlock() pair combined with for_each_process_thread() loop in kernel/hung_task.c with for_each_process_thread_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: SJ Park Reviewed-by: Lorenzo Stoakes (ARM) Reviewed-by: Oleg Nesterov --- kernel/hung_task.c | 11 ++++------- 1 file changed, 4 insertions(+), 7 deletions(-) diff --git a/kernel/hung_task.c b/kernel/hung_task.c index 6fcc94ce4ca9..73a5ad3be9a8 100644 --- 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; if (time_after(jiffies, last_break + HUNG_TASK_LOCK_BREAK)) { if (!rcu_lock_break(g, t)) - goto unlock; + goto out; last_break = jiffies; } @@ -337,9 +336,7 @@ static void check_hung_uninterruptible_tasks(unsigned long timeout) hung_task_info(t, timeout, this_round_count); } } - unlock: - rcu_read_unlock(); - +out: if (!this_round_count) return; -- 2.25.1