On Thursday, October 16, 2014 08:05:44 AM Dirk Brandewie wrote: > On 10/15/2014 04:16 PM, Pali Rohár wrote: > > 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 <[email protected]> > > Acked-by: Dirk Brandewie <[email protected]>
Applied, thanks! -- I speak only for myself. Rafael J. Wysocki, Intel Open Source Technology Center. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
