sched/uclamp: Align uclamp and util_est and call before freq update
The commit dfa0a574 ("sched/uclamg: Handle delayed dequeue") has add the sched_delayed check to prevent double uclamp_dec/inc. However, it put the uclamp_rq_inc() after enqueue_task(). This may lead to the following issues: When a task with uclamp goes through enqueue_task() and could trigger cpufreq update, its uclamp won't even be considered in the cpufreq update. It is only after enqueue will the uclamp be added to rq buckets, and cpufreq will only pick it up at the next update. This could cause a delay in frequency updating. It may affect the performance(uclamp_min > 0) or power(uclamp_max < 1024). So, just like util_est, put the uclamp_rq_inc() before enqueue_task(). And as for the sched_delayed_task, same as util_est, using the sched_delayed flag to prevent inc the sched_delayed_task's uclamp, using the ENQUEUE_DELAYED flag to allow inc the sched_delayed_task's uclamp which is being woken up. Signed-off-by:Xuewen Yan <xuewen.yan@unisoc.com> Signed-off-by:
Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by:
Vincent Guittot <vincent.guittot@linaro.org> Reviewed-by:
Dietmar Eggemann <dietmar.eggemann@arm.com> Tested-by:
Dietmar Eggemann <dietmar.eggemann@arm.com> Link: https://lore.kernel.org/r/20250417043457.10632-3-xuewen.yan@unisoc.com
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