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Kan Liang ee72a94ea4 perf/x86/intel: Fix fixed counter check warning for some Alder Lake

For some Alder Lake machine, the below fixed counter check warning may be
triggered.

[    2.010766] hw perf events fixed 5 > max(4), clipping!

Current perf unconditionally increases the number of the GP counters and
the fixed counters for a big core PMU on an Alder Lake system, because
the number enumerated in the CPUID only reflects the common counters.
The big core may has more counters. However, Alder Lake may have an
alternative configuration. With that configuration,
the X86_FEATURE_HYBRID_CPU is not set. The number of the GP counters and
fixed counters enumerated in the CPUID is accurate. Perf mistakenly
increases the number of counters. The warning is triggered.

Directly use the enumerated value on the system with the alternative
configuration.

Fixes: f83d2f91d259 ("perf/x86/intel: Add Alder Lake Hybrid support")
Reported-by: Jin Yao <yao.jin@linux.intel.com>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/1624029174-122219-2-git-send-email-kan.liang@linux.intel.com

2021-06-23 18:30:53 +02:00

alpha

Merge branch 'akpm' (patches from Andrew)

2021-05-07 00:34:51 -07:00

arc

kprobes: Do not increment probe miss count in the fault handler

2021-06-03 15:47:26 +02:00

arm

kprobes: Do not increment probe miss count in the fault handler

2021-06-03 15:47:26 +02:00

arm64

kprobes: Do not increment probe miss count in the fault handler