tree 5edf608225d61bc595e99fe76c5521501dda1624
parent c410833a3c96b325c68987c2544becad39079c33
author Stratos Karafotis <stratosk@semaphore.gr> 1405697844 -0700
committer Rafael J. Wysocki <rafael.j.wysocki@intel.com> 1405942998 +0200

cpufreq: intel_pstate: Disable interrupts during MSRs reading

According to Intel 64 and IA-32 Architectures SDM, Volume 3,
Chapter 14.2, "Software needs to exercise care to avoid delays
between the two RDMSRs (for example interrupts)".

So, disable interrupts during reading MSRs IA32_APERF and IA32_MPERF.
This should increase the accuracy of the calculations.

Signed-off-by: Stratos Karafotis <stratosk@semaphore.gr>
Signed-off-by: Dirk Brandewie <dirk.j.brandewie@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>