diff options
| -rw-r--r-- | kernel/sched/cpufreq_schedutil.c | 31 |
1 files changed, 23 insertions, 8 deletions
diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c index 758efd7f3abe..a84641b222c1 100644 --- a/kernel/sched/cpufreq_schedutil.c +++ b/kernel/sched/cpufreq_schedutil.c @@ -47,6 +47,8 @@ struct sugov_cpu { struct update_util_data update_util; struct sugov_policy *sg_policy; + unsigned int cached_raw_freq; + /* The fields below are only needed when sharing a policy. */ unsigned long util; unsigned long max; @@ -106,7 +108,7 @@ static void sugov_update_commit(struct sugov_policy *sg_policy, u64 time, /** * get_next_freq - Compute a new frequency for a given cpufreq policy. - * @policy: cpufreq policy object to compute the new frequency for. + * @sg_cpu: schedutil cpu object to compute the new frequency for. * @util: Current CPU utilization. * @max: CPU capacity. * @@ -121,14 +123,25 @@ static void sugov_update_commit(struct sugov_policy *sg_policy, u64 time, * next_freq = C * curr_freq * util_raw / max * * Take C = 1.25 for the frequency tipping point at (util / max) = 0.8. + * + * The lowest driver-supported frequency which is equal or greater than the raw + * next_freq (as calculated above) is returned, subject to policy min/max and + * cpufreq driver limitations. */ -static unsigned int get_next_freq(struct cpufreq_policy *policy, - unsigned long util, unsigned long max) +static unsigned int get_next_freq(struct sugov_cpu *sg_cpu, unsigned long util, + unsigned long max) { + struct sugov_policy *sg_policy = sg_cpu->sg_policy; + struct cpufreq_policy *policy = sg_policy->policy; unsigned int freq = arch_scale_freq_invariant() ? policy->cpuinfo.max_freq : policy->cur; - return (freq + (freq >> 2)) * util / max; + freq = (freq + (freq >> 2)) * util / max; + + if (freq == sg_cpu->cached_raw_freq && sg_policy->next_freq != UINT_MAX) + return sg_policy->next_freq; + sg_cpu->cached_raw_freq = freq; + return cpufreq_driver_resolve_freq(policy, freq); } static void sugov_update_single(struct update_util_data *hook, u64 time, @@ -143,13 +156,14 @@ static void sugov_update_single(struct update_util_data *hook, u64 time, return; next_f = util == ULONG_MAX ? policy->cpuinfo.max_freq : - get_next_freq(policy, util, max); + get_next_freq(sg_cpu, util, max); sugov_update_commit(sg_policy, time, next_f); } -static unsigned int sugov_next_freq_shared(struct sugov_policy *sg_policy, +static unsigned int sugov_next_freq_shared(struct sugov_cpu *sg_cpu, unsigned long util, unsigned long max) { + struct sugov_policy *sg_policy = sg_cpu->sg_policy; struct cpufreq_policy *policy = sg_policy->policy; unsigned int max_f = policy->cpuinfo.max_freq; u64 last_freq_update_time = sg_policy->last_freq_update_time; @@ -189,7 +203,7 @@ static unsigned int sugov_next_freq_shared(struct sugov_policy *sg_policy, } } - return get_next_freq(policy, util, max); + return get_next_freq(sg_cpu, util, max); } static void sugov_update_shared(struct update_util_data *hook, u64 time, @@ -206,7 +220,7 @@ static void sugov_update_shared(struct update_util_data *hook, u64 time, sg_cpu->last_update = time; if (sugov_should_update_freq(sg_policy, time)) { - next_f = sugov_next_freq_shared(sg_policy, util, max); + next_f = sugov_next_freq_shared(sg_cpu, util, max); sugov_update_commit(sg_policy, time, next_f); } @@ -433,6 +447,7 @@ static int sugov_start(struct cpufreq_policy *policy) sg_cpu->util = ULONG_MAX; sg_cpu->max = 0; sg_cpu->last_update = 0; + sg_cpu->cached_raw_freq = 0; cpufreq_add_update_util_hook(cpu, &sg_cpu->update_util, sugov_update_shared); } else { |