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h=Date:From:To:Cc:Subject:References:In-Reply-To; b=XRC2+2eun6nn01MuOy3pLsHfxu9LlV+nJ/7enwoG457a25DF4U95wpahgGNE/Mkpl rLWt1ASQbCeSG/i9QLz1ZnPcaCy6u4EsPOMutcqfGQwolvE3pFYvj3CLi0gH/jHIaP VSX9+ZExqzazlzJ/gYokn6P0ZUcZVcJyNCXQ1YbNatoMUV8yAdvk5jDDyWamOxAvv3 +7aUUDC5HzU5NJnVD+GkGmgbm6fa2/R9eIMCLeZ3Ns7wFIlGEhWI+Y0nIqbVg2rjid pJOLNmP3BAjh+U1aeOA7DovmGfdTvNbJn34KVmWPthoAFJm0y6LO+cDAw3Iwnhc/n6 Nx/Wwb0dP0rPg== Date: Mon, 7 Sep 2026 13:27:32 +0100 From: "Lorenzo Stoakes (ARM)" To: Ye Liu Cc: Andrew Morton , Ye Liu , Michal Hocko , 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, 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, 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: Re: [PATCH v2 7/8] lib: convert process iterator to for_each_process_rculock Message-ID: References: <20260907081334.1152889-1-ye.liu@linux.dev> <20260907081334.1152889-8-ye.liu@linux.dev> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260907081334.1152889-8-ye.liu@linux.dev> X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: 7381318000D X-Stat-Signature: g66anpzunugmu33jqsdr5obfz7uktmhu X-Rspam-User: X-HE-Tag: 1788784068-138275 X-HE-Meta: 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 1Zc9OZF/ hSjCupxhbTJb4LxflHg/SVvQhlM6UEfoPSbvSAM+7DmJ2YZHoooGqaZWDLD97Ls3acJ6y6mD75He0oZQ8YPrLPjdKjn6Pj/5ilXrVaG+zYScM94gz5b0yri77WNH89PDErdkIylLdE8xCN7Rt6s1viOhTEagSS9fRb2ULhsGNki1ed2yGtdqxkuFQAAmPJ9Lp1y/VFDSsTAocKWzw0TVMnm9ckTIpvVVIBBMsSBJs7KpQxEG7A3yuCudCMTwiItmCbH3L9e6YGMLiTwmS+c81pJTL+SK2h4Zhebrdho6P1jhaq3YYtZ3dCsYL4ufPwNxYkVY4iBHhreaG5KD6Ans2c+MnZaUczkwiWdL5BcIMeXlSUQ7hx4Fsxj9QoSbXblp0OySjyN4RQyB8EGWt74V2u/PyuAGUgOvLxgL1WWfYZS/Ki7AIiuCKdTa9cBA26LRA9brH9YpWPdMUqbY= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Mon, Sep 07, 2026 at 04:13:33PM +0800, Ye Liu wrote: > 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 LGTM so: Reviewed-by: Lorenzo Stoakes (ARM) > --- > 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 > -- Cheers, Lorenzo