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Then the CPU > where the schedule_timeout() was executed to enqueue the timer comes out of > idle and restarts the timer using schedule_timeout() and goes back to idle > again. This is due to the fair scheduler which tries to keep the task on > the CPU which it previously executed on. Regarding above, are you referring to "wake_up_process(timeout->task)" in "process_timeout()" ends up waking the task on an idle CPU instead of the CPU where process_timeout() ran? In which case, have you tried using the "WF_CURRENT_CPU" flag for the wakeup? (landed upstream in v6.6-rc1) It is only used by wait queues in kernel/sched/wait.c currently but perhaps we can have a "wake_up_process_on_current_cpu()" that process_timeout() can call. Something along the lines of: int wake_up_process_on_current_cpu(struct task_struct *p) { return try_to_wake_up(p, TASK_NORMAL, WF_CURRENT_CPU); } EXPORT_SYMBOL(wake_up_process_on_current_cpu); Thoughts? > > [..snip..] > -- Thanks and Regards, Prateek