On 01/21/2016 07:27 PM, Seiichi Ikarashi wrote: > On 2016-01-22 01:15, Prarit Bhargava wrote: >> The MSR_PKG_POWER_INFO register (Intel ASDM, section 14.9.3 >> "Package RAPL Domain") provides a maximum time window which the >> system can support. This window is read-only and is currently >> not examined when setting the time windows for the package. >> >> This patch implements get_max_time_window_us() and checks the window when >> a user attempts to set power capping for the package. >> >> Before the patch it was possible to set the window to, for example, 10000 >> micro seconds: >> >> [root@intel-chiefriver-03 rhel7]# echo 10000 > >> /sys/devices/virtual/powercap/intel-rapl/intel-rapl\:0/constraint_0_time_window_us; >> egrep ^ >> /sys/devices/virtual/powercap/intel-rapl/intel-rapl\:0/constraint_0_time_window_us >> >> /sys/devices/virtual/powercap/intel-rapl/intel-rapl:0/constraint_0_time_window_us:1:9765 >> >> but from 'turbostat -d', the package is limited to 976us: >> >> cpu0: MSR_PKG_POWER_INFO: 0x01200168 (45 W TDP, RAPL 36 - 0 W, 0.000977 sec.) >> >> (Note, there appears to be a rounding issue in turbostat which needs to >> also be fixed. Looking at the values in the register it is clear the >> value is 1/1024 = 976us.) >> >> After the patch we are limited by the maximum time window: >> >> [root@intel-chiefriver-03 rhel7]# echo 10000 > >> /sys/devices/virtual/powercap/intel-rapl/intel-rapl\:0/constraint_0_time_window_us; >> egrep ^ >> /sys/devices/virtual/powercap/intel-rapl/intel-rapl\:0/constraint_0_time_window_us >> >> -bash: echo: write error: Invalid argument >> /sys/devices/virtual/powercap/intel-rapl/intel-rapl:0/constraint_0_time_window_us:1:976 >> >> Cc: "Rafael J. Wysocki" <rafael.j.wyso...@intel.com> >> Cc: Prarit Bhargava <pra...@redhat.com> >> Cc: Radivoje Jovanovic <radivoje.jovano...@intel.com> >> Cc: Seiichi Ikarashi <s.ikara...@jp.fujitsu.com> >> Cc: Mathias Krause <mini...@googlemail.com> >> Cc: Ajay Thomas <ajay.thomas.david.rajamanic...@intel.com> >> Signed-off-by: Prarit Bhargava <pra...@redhat.com> >> --- >> drivers/powercap/intel_rapl.c | 31 +++++++++++++++++++++++++++++++ >> drivers/powercap/powercap_sys.c | 6 ++++-- >> 2 files changed, 35 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/powercap/intel_rapl.c b/drivers/powercap/intel_rapl.c >> index cc97f08..f765b2c 100644 >> --- a/drivers/powercap/intel_rapl.c >> +++ b/drivers/powercap/intel_rapl.c >> @@ -493,13 +493,42 @@ static int get_current_power_limit(struct >> powercap_zone *power_zone, int id, >> return ret; >> } >> >> +static int get_max_time_window(struct powercap_zone *power_zone, int id, >> + u64 *data) > > The 2nd arg "id" is not necessary.
It is required by the powercap_sys code. If I remove this then I have to create separate sysfs store and show files and I think it isn't worth it to do so. P. > > -- > Seiichi >
