Merge back intel_pstate fixes for v4.6.

* pm-cpufreq:
  intel_pstate: Avoid extra invocation of intel_pstate_sample()
  intel_pstate: Do not set utilization update hook too early
This commit is contained in:
Rafael J. Wysocki 2016-04-02 01:07:17 +02:00
commit 9fa64d6424
1 changed files with 32 additions and 12 deletions

View File

@ -910,7 +910,14 @@ static inline bool intel_pstate_sample(struct cpudata *cpu, u64 time)
cpu->prev_aperf = aperf;
cpu->prev_mperf = mperf;
cpu->prev_tsc = tsc;
return true;
/*
* First time this function is invoked in a given cycle, all of the
* previous sample data fields are equal to zero or stale and they must
* be populated with meaningful numbers for things to work, so assume
* that sample.time will always be reset before setting the utilization
* update hook and make the caller skip the sample then.
*/
return !!cpu->last_sample_time;
}
static inline int32_t get_avg_frequency(struct cpudata *cpu)
@ -984,8 +991,7 @@ static inline int32_t get_target_pstate_use_performance(struct cpudata *cpu)
* enough period of time to adjust our busyness.
*/
duration_ns = cpu->sample.time - cpu->last_sample_time;
if ((s64)duration_ns > pid_params.sample_rate_ns * 3
&& cpu->last_sample_time > 0) {
if ((s64)duration_ns > pid_params.sample_rate_ns * 3) {
sample_ratio = div_fp(int_tofp(pid_params.sample_rate_ns),
int_tofp(duration_ns));
core_busy = mul_fp(core_busy, sample_ratio);
@ -1100,10 +1106,8 @@ static int intel_pstate_init_cpu(unsigned int cpunum)
intel_pstate_get_cpu_pstates(cpu);
intel_pstate_busy_pid_reset(cpu);
intel_pstate_sample(cpu, 0);
cpu->update_util.func = intel_pstate_update_util;
cpufreq_set_update_util_data(cpunum, &cpu->update_util);
pr_debug("intel_pstate: controlling: cpu %d\n", cpunum);
@ -1122,18 +1126,33 @@ static unsigned int intel_pstate_get(unsigned int cpu_num)
return get_avg_frequency(cpu);
}
static void intel_pstate_set_update_util_hook(unsigned int cpu_num)
{
struct cpudata *cpu = all_cpu_data[cpu_num];
/* Prevent intel_pstate_update_util() from using stale data. */
cpu->sample.time = 0;
cpufreq_set_update_util_data(cpu_num, &cpu->update_util);
}
static void intel_pstate_clear_update_util_hook(unsigned int cpu)
{
cpufreq_set_update_util_data(cpu, NULL);
synchronize_sched();
}
static int intel_pstate_set_policy(struct cpufreq_policy *policy)
{
if (!policy->cpuinfo.max_freq)
return -ENODEV;
intel_pstate_clear_update_util_hook(policy->cpu);
if (policy->policy == CPUFREQ_POLICY_PERFORMANCE &&
policy->max >= policy->cpuinfo.max_freq) {
pr_debug("intel_pstate: set performance\n");
limits = &performance_limits;
if (hwp_active)
intel_pstate_hwp_set(policy->cpus);
return 0;
goto out;
}
pr_debug("intel_pstate: set powersave\n");
@ -1163,6 +1182,9 @@ static int intel_pstate_set_policy(struct cpufreq_policy *policy)
limits->max_perf = div_fp(int_tofp(limits->max_perf_pct),
int_tofp(100));
out:
intel_pstate_set_update_util_hook(policy->cpu);
if (hwp_active)
intel_pstate_hwp_set(policy->cpus);
@ -1187,8 +1209,7 @@ static void intel_pstate_stop_cpu(struct cpufreq_policy *policy)
pr_debug("intel_pstate: CPU %d exiting\n", cpu_num);
cpufreq_set_update_util_data(cpu_num, NULL);
synchronize_sched();
intel_pstate_clear_update_util_hook(cpu_num);
if (hwp_active)
return;
@ -1455,8 +1476,7 @@ out:
get_online_cpus();
for_each_online_cpu(cpu) {
if (all_cpu_data[cpu]) {
cpufreq_set_update_util_data(cpu, NULL);
synchronize_sched();
intel_pstate_clear_update_util_hook(cpu);
kfree(all_cpu_data[cpu]);
}
}