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[36.225.77.225]) by smtp.gmail.com with ESMTPSA id d2e1a72fcca58-835433e5bf7sm2503890b3a.10.2026.05.03.06.11.01 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 03 May 2026 06:11:03 -0700 (PDT) Date: Sun, 3 May 2026 21:10:59 +0800 From: Cheng-Yang Chou To: Zqiang Cc: tj@kernel.org, void@manifault.com, arighi@nvidia.com, changwoo@igalia.com, sched-ext@lists.linux.dev, linux-kernel@vger.kernel.org, Ching-Chun Huang , Chia-Ping Tsai Subject: Re: [PATCH] sched_ext: Remove redundant rcu_read_lock/unlock() in sysrq_handle_sched_ext_reset() Message-ID: <20260503210256.G4259@cchengyang.duckdns.org> References: <20260430084543.25137-1-qiang.zhang@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: <20260430084543.25137-1-qiang.zhang@linux.dev> Hi Zqiang, On Thu, Apr 30, 2026 at 04:45:43PM +0800, Zqiang wrote: > The sysrq_handle_sched_ext_reset() callback has already been > executed in the rcu read critical section within __handle_sysrq(), > this commit therefore remove redundant rcu_read_lock/unlock() in Nit: s/remove/removes Looks good! Reviewed-by: Cheng-Yang Chou > the sysrq_handle_sched_ext_reset(). > > Signed-off-by: Zqiang > --- > kernel/sched/ext.c | 2 -- > 1 file changed, 2 deletions(-) > > diff --git a/kernel/sched/ext.c b/kernel/sched/ext.c > index 45a2668284bc..0f3e9d088151 100644 > --- a/kernel/sched/ext.c > +++ b/kernel/sched/ext.c > @@ -7953,13 +7953,11 @@ static void sysrq_handle_sched_ext_reset(u8 key) > { > struct scx_sched *sch; > > - rcu_read_lock(); > sch = rcu_dereference(scx_root); > if (likely(sch)) > scx_disable(sch, SCX_EXIT_SYSRQ); > else > pr_info("sched_ext: BPF schedulers not loaded\n"); > - rcu_read_unlock(); > } > > static const struct sysrq_key_op sysrq_sched_ext_reset_op = { > -- > 2.17.1 > > -- Cheers, Cheng-Yang