Messages in this thread Patch in this message | | | From | Pali Rohár <> | Subject | [PATCH] cpufreq: intel_pstate: Fix setting max_perf_pct in performance policy | Date | Thu, 16 Oct 2014 01:16:51 +0200 |
| |
Code which changes policy to powersave changes also max_policy_pct based on max_freq. Code which change max_perf_pct has upper limit base on value max_policy_pct. When policy is changing from powersave back to performance then max_policy_pct is not changed. Which means that changing max_perf_pct is not possible to high values if max_freq was too low in powersave policy.
Test case:
$ cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_min_freq 800000 $ cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq 3300000 $ cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor performance $ cat /sys/devices/system/cpu/intel_pstate/max_perf_pct 100
$ echo powersave > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor $ echo 800000 > /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq $ echo 20 > /sys/devices/system/cpu/intel_pstate/max_perf_pct
$ cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor powersave $ cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq 800000 $ cat /sys/devices/system/cpu/intel_pstate/max_perf_pct 20
$ echo performance > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor $ echo 3300000 > /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq $ echo 100 > /sys/devices/system/cpu/intel_pstate/max_perf_pct
$ cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor performance $ cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq 3300000 $ cat /sys/devices/system/cpu/intel_pstate/max_perf_pct 24
And now intel_pstate driver allows to set maximal value for max_perf_pct based on max_policy_pct which is 24 for previous powersave max_freq 800000.
This patch will set default value for max_policy_pct when setting policy to performance so it will allow to set also max value for max_perf_pct.
Signed-off-by: Pali Rohár <pali.rohar@gmail.com> Cc: stable@vger.kernel.org --- drivers/cpufreq/intel_pstate.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c index 0668b38..7547ab5 100644 --- a/drivers/cpufreq/intel_pstate.c +++ b/drivers/cpufreq/intel_pstate.c @@ -714,6 +714,7 @@ static int intel_pstate_set_policy(struct cpufreq_policy *policy) if (policy->policy == CPUFREQ_POLICY_PERFORMANCE) { limits.min_perf_pct = 100; limits.min_perf = int_tofp(1); + limits.max_policy_pct = 100; limits.max_perf_pct = 100; limits.max_perf = int_tofp(1); limits.no_turbo = limits.turbo_disabled; -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |