From 0070ea29623904224c0f5fa279a16a4ac9223295 Mon Sep 17 00:00:00 2001 From: Wei Wang Date: Fri, 16 Oct 2020 11:17:22 -0700 Subject: cpufreq: schedutil: restore cached freq when next_f is not changed We have the raw cached freq to reduce the chance in calling cpufreq driver where it could be costly in some arch/SoC. Currently, the raw cached freq is reset in sugov_update_single() when it avoids frequency reduction (which is not desirable sometimes), but it is better to restore the previous value of it in that case, because it may not change in the next cycle and it is not necessary to change the CPU frequency then. Adapted from https://android-review.googlesource.com/1352810/ Signed-off-by: Wei Wang Acked-by: Viresh Kumar [ rjw: Subject edit and changelog rewrite ] Signed-off-by: Rafael J. Wysocki --- kernel/sched/cpufreq_schedutil.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'kernel') diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c index 5ae7b4e6e8d6..e254745a82cb 100644 --- a/kernel/sched/cpufreq_schedutil.c +++ b/kernel/sched/cpufreq_schedutil.c @@ -441,6 +441,7 @@ static void sugov_update_single(struct update_util_data *hook, u64 time, unsigned long util, max; unsigned int next_f; bool busy; + unsigned int cached_freq = sg_policy->cached_raw_freq; sugov_iowait_boost(sg_cpu, time, flags); sg_cpu->last_update = time; @@ -464,8 +465,8 @@ static void sugov_update_single(struct update_util_data *hook, u64 time, if (busy && next_f < sg_policy->next_freq) { next_f = sg_policy->next_freq; - /* Reset cached freq as next_freq has changed */ - sg_policy->cached_raw_freq = 0; + /* Restore cached freq as next_freq has changed */ + sg_policy->cached_raw_freq = cached_freq; } /* -- cgit