linux

iv/linux

History

Kan Liang 80a5ce116f perf/x86/intel: Check perf metrics feature for each CPU

It might be possible that different CPUs have different CPU metrics on a
platform. In this case, writing the GLOBAL_CTRL_EN_PERF_METRICS bit to
the GLOBAL_CTRL register of a CPU, which doesn't support the TopDown
perf metrics feature, causes MSR access error.

Current TopDown perf metrics feature is enumerated using the boot CPU's
PERF_CAPABILITIES MSR. The MSR only indicates the boot CPU supports this
feature.

Check the PERF_CAPABILITIES MSR for each CPU. If any CPU doesn't support
the perf metrics feature, disable the feature globally.

Fixes: 59a854e2f3b9 ("perf/x86/intel: Support TopDown metrics on Ice Lake")
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20201001211711.25708-1-kan.liang@linux.intel.com

2020-10-03 16:30:56 +02:00

bts.c

perf/x86: Replace zero-length array with flexible-array

2020-05-19 20:34:16 +02:00

core.c

perf/x86/intel: Check perf metrics feature for each CPU

2020-10-03 16:30:56 +02:00

cstate.c

perf/x86/cstate: Add Jasper Lake CPU support

2020-04-22 21:43:12 +02:00

ds.c

perf/x86/intel/ds: Fix x86_pmu_stop warning for large PEBS