diff options
| author | Joonwoo Park <joonwoop@codeaurora.org> | 2016-12-20 15:23:53 -0800 |
|---|---|---|
| committer | Joel Fernandes <joelaf@google.com> | 2017-10-19 11:56:50 -0700 |
| commit | 40c3aaa56a68455a1c8eccff1bb23d853d8e239c (patch) | |
| tree | 55bf0b99c30aca12c018cdf88b5e23be96ad46e6 /kernel | |
| parent | 7ab48e4c8d9e0652bd978f3df26c29e64b5ea85a (diff) | |
cpufreq: sched: update capacity request upon tick always
At present, sched_freq_tick() skips updating of capacity update when
current frequency is fmax. This can cause incorrect frequency drop
when a CPU bound task goes into sleep for example :
1) A task (A) enqueues onto CPU 0 and executes for long time.
2) A new task (B) which has low task demand enqueues onto CPU 1 and
executes long so becomes a CPU bound task.
3) Both CPU 0 and 1 gets scheduler tick but skip sched_freq_tick()
since current frequency is fmax.
4) Task (A) sleeps and lower the CPU 0's capacity request.
5) Because task (B) voted CPU capacity at step 2 with low demand and
skipped to request afterwards, cluster frequency for both CPU 0
and 1 drops to match capacity voted by CPU 1 at step 2 even though
task (B) on CPU 1 requires max capacity.
Fix such incorrectness by not skipping CPU capacity voting at tick
path.
Change-Id: Ieb46af1ac96ffce7a5532c58c7f07bf1ada06b86
Signed-off-by: Joonwoo Park <joonwoop@codeaurora.org>
Signed-off-by: Vikram Mulukutla <markivx@codeaurora.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/sched/core.c | 7 |
1 files changed, 0 insertions, 7 deletions
diff --git a/kernel/sched/core.c b/kernel/sched/core.c index fec7b2c4f9fd..f747e373ed6f 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -3025,16 +3025,9 @@ static void sched_freq_tick_walt(int cpu) static void sched_freq_tick(int cpu) { - unsigned long capacity_orig, capacity_curr; - if (!sched_freq()) return; - capacity_orig = capacity_orig_of(cpu); - capacity_curr = capacity_curr_of(cpu); - if (capacity_curr == capacity_orig) - return; - _sched_freq_tick(cpu); } #else |