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[31.46.243.229]) by smtp.gmail.com with ESMTPSA id iv20-20020a05600c549400b0041313d4c852sm3162899wmb.19.2024.03.08.02.15.46 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 08 Mar 2024 02:15:47 -0800 (PST) Sender: Ingo Molnar Date: Fri, 8 Mar 2024 11:15:45 +0100 From: Ingo Molnar To: Vincent Guittot Cc: Valentin Schneider , linux-kernel@vger.kernel.org, Shrikanth Hegde , Peter Zijlstra , Dietmar Eggemann , Linus Torvalds Subject: Re: [PATCH 6/9] sched/balancing: Update run_rebalance_domains() comments Message-ID: References: <20240304094831.3639338-1-mingo@kernel.org> <20240304094831.3639338-7-mingo@kernel.org> 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: * Vincent Guittot wrote: > > """ > > The run_rebalance_domains() softirq handler is triggered via SCHED_SOFTIRQ > > from two places: > > > > - directly from trigger_load_balance() in scheduler_tick(), for periodic > > load balance > > > > - indirectly from kick_ilb() (invoked down the scheduler_tick() too), which > > issues an SMP cross-call to nohz_csd_func() which will itself raise the > > softirq, for NOHZ idle balancing. > > I'm not sure that we should provide too many details of the path as > this might change in the future. What about the below ? > > - directly from the local scheduler_tick() for periodic load balance > > - indirectly from a remote scheduler_tick() for NOHZ idle balancing > through the SMP cross-call nohz_csd_func() Okay - I updated it to: /* * This softirq handler is triggered via SCHED_SOFTIRQ from two places: * * - directly from the local scheduler_tick() for periodic load balancing * * - indirectly from a remote scheduler_tick() for NOHZ idle balancing * through the SMP cross-call nohz_csd_func() */ static __latent_entropy void run_rebalance_domains(struct softirq_action *h) Does this work with everyone? Thanks, Ingo