On 3/16/2016 1:00 PM, 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>
Can you please resend the patches with CCs to linux...@vger.kernel.org?
They are much easier to handle to me then.
Thanks,
Rafael
