Messages in this thread | | | Date | Wed, 15 Jan 2020 16:35:11 +0100 | From | Peter Zijlstra <> | Subject | Re: [PATCH] sched/fair: remove redundant call to cpufreq_update_util |
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On Wed, Jan 15, 2020 at 11:20:20AM +0100, Vincent Guittot wrote: > With commit bef69dd87828 ("sched/cpufreq: Move the cfs_rq_util_change() call to cpufreq_update_util()") > update_load_avg() has become the central point for calling cpufreq (not > including the update of blocked load). This change helps to simplify > further the number of call to cpufreq_update_util() and to remove last > redundant ones. With update_load_avg(), we are now sure that > cpufreq_update_util() will be called after every task attachment to a > cfs_rq and especially after propagating this event down to the util_avg of > the root cfs_rq, which is the level that is used by cpufreq governors like > schedutil to set the frequency of a CPU. > > The SCHED_CPUFREQ_MIGRATION flag forces an early call to cpufreq when the > migration happens in a cgroup whereas util_avg of root cfs_rq is not yet > updated and this call is duplicated with the one that happens immediately > after when the migration event reaches the root cfs_rq. The dedicated flag > SCHED_CPUFREQ_MIGRATION is now useless and can be removed. The interface of > attach_entity_load_avg() can also be simplified accordingly. > > Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Thanks!
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