perf/x86/rapl: Only check lower 32bits for RAPL energy counters

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In the RAPL ENERGY_COUNTER MSR, only the lower 32bits represent the energy
counter.

On previous platforms, the higher 32bits are reverved and always return
Zero. But on Intel SapphireRapids platform, the higher 32bits are reused
for other purpose and return non-zero value.

Thus check the lower 32bits only for these ENERGY_COUTNER MSRs, to make
sure the RAPL PMU events are not added erroneously when higher 32bits
contain non-zero value.

Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Link: https://lkml.kernel.org/r/20210204161816.12649-2-rui.zhang@intel.com

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Zhang Rui 2021-02-05 00:18:15 +08:00 • committed by Peter Zijlstra

parent ffb20c2e52

commit b6f78d3fba

1 changed files with 8 additions and 5 deletions

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arch/x86/events/rapl.c

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