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Tue, 22 Sep 2026 08:25:31 +0000 Message-ID: <65ee9df8-2422-4d1a-80d6-41ac51979da1@intel.com> Date: Tue, 22 Sep 2026 16:25:14 +0800 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 1/6] sched/cache: Keep nr_pref_llc_running in the runnable domain To: Peter Zijlstra , Tim Chen CC: Ingo Molnar , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Valentin Schneider , K Prateek Nayak , Kees Cook , Christian Brauner , Alexander Viro , Jan Kara , Shrikanth Hegde , Qais Yousef , Aaron Lu , Srikar Dronamraju , "Vineeth Remanan Pillai" , Ricardo Neri-Calderon , Lu Wang , Hyunwoo Kim , Zhan Xusheng , "Zhan Xusheng" , Yi Lai , "Rafael J . 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>> >> static void set_delayed(struct sched_entity *se) >> { >> - se->sched_delayed = 1; >> - >> /* >> * Delayed se of cfs_rq have no tasks queued on them. >> * Do not adjust h_nr_runnable since __dequeue_task() >> * will account it for blocked tasks. >> + * >> + * This check can be removed because when flat pick >> + * patches get merged as only task can get delayed, >> + * same for clear_delayed(). >> */ >> - if (!entity_is_task(se)) >> + if (!entity_is_task(se)) { >> + se->sched_delayed = 1; >> return; >> + } > > This is dead code. In Linus' tree, where this will be applied, this can > never happen. A possible backport of this fix however will need to take > care. > Would you prefer that we create a separate patch to remove entity_is_task() for Linus's tree (so that the current patch can be backported, since cache-aware scheduling was merged before flat task-pickup)? thanks, Chenyu