Commits
Venkatesh Srinivas committed 24223657806
perf/x86/intel: Use rdmsrl_safe() when initializing RAPL PMU CPUs which should support the RAPL counters according to Family/Model/Stepping may still issue #GP when attempting to access the RAPL MSRs. This may happen when Linux is running under KVM and we are passing-through host F/M/S data, for example. Use rdmsrl_safe to first access the RAPL_POWER_UNIT MSR; if this fails, do not attempt to use this PMU. Signed-off-by: Venkatesh Srinivas <venkateshs@google.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1394739386-22260-1-git-send-email-venkateshs@google.com Cc: zheng.z.yan@intel.com Cc: eranian@google.com Cc: ak@linux.intel.com Cc: linux-kernel@vger.kernel.org [ The patch also silently fixes another bug: rapl_pmu_init() didn't handle the memory alloc failure case previously. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>