OpenE2K
/
linux
6
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity
linux/kernel/sched
History
Vincent Guittot 0e9619ff10 sched/cpufreq: Move the cfs_rq_util_change() call to cpufreq_update_util() 
[ Upstream commit bef69dd878 ]

update_cfs_rq_load_avg() calls cfs_rq_util_change() every time PELT decays,
which might be inefficient when the cpufreq driver has rate limitation.

When a task is attached on a CPU, we have this call path:

update_load_avg()
  update_cfs_rq_load_avg()
    cfs_rq_util_change -- > trig frequency update
  attach_entity_load_avg()
    cfs_rq_util_change -- > trig frequency update

The 1st frequency update will not take into account the utilization of the
newly attached task and the 2nd one might be discarded because of rate
limitation of the cpufreq driver.

update_cfs_rq_load_avg() is only called by update_blocked_averages()
and update_load_avg() so we can move the call to
cfs_rq_util_change/cpufreq_update_util() into these two functions.

It's also interesting to note that update_load_avg() already calls
cfs_rq_util_change() directly for the !SMP case.

This change will also ensure that cpufreq_update_util() is called even
when there is no more CFS rq in the leaf_cfs_rq_list to update, but only
IRQ, RT or DL PELT signals.

[ mingo: Minor updates. ]

Reported-by: Doug Smythies <dsmythies@telus.net>
Tested-by: Doug Smythies <dsmythies@telus.net>
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: juri.lelli@redhat.com
Cc: linux-pm@vger.kernel.org
Cc: mgorman@suse.de
Cc: rostedt@goodmis.org
Cc: sargun@sargun.me
Cc: srinivas.pandruvada@linux.intel.com
Cc: tj@kernel.org
Cc: xiexiuqi@huawei.com
Cc: xiezhipeng1@huawei.com
Fixes: 039ae8bcf7 ("sched/fair: Fix O(nr_cgroups) in the load balancing path")
Link: https://lkml.kernel.org/r/1574083279-799-1-git-send-email-vincent.guittot@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
 		2020-01-26 10:01:08 +01:00
..
Makefile
…
autogroup.c
…
autogroup.h
…
clock.c
…
completion.c
…
core.c sched/uclamp: Fix overzealous type replacement 2019-12-31 16:45:37 +01:00
cpuacct.c
…
cpudeadline.c
…
cpudeadline.h
…
cpufreq.c cpufreq: Avoid leaving stale IRQ work items during CPU offline 2019-12-31 16:46:06 +01:00
cpufreq_schedutil.c cpufreq: Avoid leaving stale IRQ work items during CPU offline 2019-12-31 16:46:06 +01:00
cpupri.c
…
cpupri.h
…
cputime.c sched/vtime: Fix guest/system mis-accounting on task switch 2019-10-09 12:38:03 +02:00
deadline.c sched/core: Further clarify sched_class::set_next_task() 2020-01-26 10:01:03 +01:00
debug.c
…
fair.c sched/cpufreq: Move the cfs_rq_util_change() call to cpufreq_update_util() 2020-01-26 10:01:08 +01:00
features.h
…
idle.c sched/core: Further clarify sched_class::set_next_task() 2020-01-26 10:01:03 +01:00
isolation.c
…
loadavg.c
…
membarrier.c membarrier: Fix RCU locking bug caused by faulty merge 2019-10-01 21:27:50 +02:00
pelt.c
…
pelt.h
…
psi.c psi: Fix a division error in psi poll() 2020-01-12 12:21:36 +01:00
rt.c sched/core: Further clarify sched_class::set_next_task() 2020-01-26 10:01:03 +01:00
sched-pelt.h
…
sched.h sched/core: Further clarify sched_class::set_next_task() 2020-01-26 10:01:03 +01:00
stats.c
…
stats.h
…
stop_task.c sched/core: Further clarify sched_class::set_next_task() 2020-01-26 10:01:03 +01:00
swait.c
…
topology.c sched/topology: Allow sched_asym_cpucapacity to be disabled 2019-10-29 09:58:46 +01:00
wait.c
…
wait_bit.c
…