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[213.44.135.146]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-48fe53ab6aasm337171385e9.2.2026.05.19.02.25.26 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 19 May 2026 02:25:26 -0700 (PDT) From: Valentin Schneider To: Shrikanth Hegde , mingo@kernel.org, peterz@infradead.org, vincent.guittot@linaro.org, linux-kernel@vger.kernel.org Cc: sshegde@linux.ibm.com, kprateek.nayak@amd.com, juri.lelli@redhat.com, dietmar.eggemann@arm.com, tj@kernel.org, rostedt@goodmis.org, mgorman@suse.de, bsegall@google.com, arighi@nvidia.com, pauld@redhat.com Subject: Re: [PATCH v4 3/4] sched/fair: Add sched_smt_active check for fastpaths In-Reply-To: <20260515172456.542799-4-sshegde@linux.ibm.com> References: <20260515172456.542799-1-sshegde@linux.ibm.com> <20260515172456.542799-4-sshegde@linux.ibm.com> Date: Tue, 19 May 2026 11:25:25 +0200 Message-ID: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain On 15/05/26 22:54, Shrikanth Hegde wrote: > For fastpaths such as wakeup and load balance even minimal code additions > can add up. is_core_idle is accessed during load balance. > > Other callsites of is_core_idle make sched_smt_active() check first. > Make the same check in should_we_balance. > > Rest of access to cpu_smt_mask isn't in fastpath. > > Note: Remove the stale comment above is_core_idle. Enqueue methods > of fair aren't close to it anymore. > > Suggested-by: K Prateek Nayak > Signed-off-by: Shrikanth Hegde Reviewed-by: Valentin Schneider