diff options
| author | Dietmar Eggemann <dietmar.eggemann@arm.com> | 2015-09-17 16:10:56 +0100 |
|---|---|---|
| committer | Leo Yan <leo.yan@linaro.org> | 2016-05-10 16:49:48 +0800 |
| commit | 259bd4cd8a4c5776e86ae1a86f1f8e1168e84212 (patch) | |
| tree | dbdc4dbc80be329a015e6898d052664fa07aba19 /include/linux | |
| parent | 0ecbd590a7175818fcbccc9d5b1dc819aae25c86 (diff) | |
cpufreq: Frequency invariant scheduler load-tracking support
Implements cpufreq_scale_freq_capacity() to provide the scheduler with a
frequency scaling correction factor for more accurate load-tracking.
The factor is:
current_freq(cpu) << SCHED_CAPACITY_SHIFT / max_freq(cpu)
In fact, freq_scale should be a struct cpufreq_policy data member. But
this would require that the scheduler hot path (__update_load_avg()) would
have to grab the cpufreq lock. This can be avoided by using per-cpu data
initialized to SCHED_CAPACITY_SCALE for freq_scale.
Signed-off-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/cpufreq.h | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h index 177c7680c1a8..11c65f536b6c 100644 --- a/include/linux/cpufreq.h +++ b/include/linux/cpufreq.h @@ -616,4 +616,7 @@ unsigned int cpufreq_generic_get(unsigned int cpu); int cpufreq_generic_init(struct cpufreq_policy *policy, struct cpufreq_frequency_table *table, unsigned int transition_latency); + +struct sched_domain; +unsigned long cpufreq_scale_freq_capacity(struct sched_domain *sd, int cpu); #endif /* _LINUX_CPUFREQ_H */ |