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ARM: 7117/1: perf: fix HW_CACHE_* events on Cortex-A9
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Using COHERENT_LINE_{MISS,HIT} for cache misses and references
respectively is completely wrong. Instead, use the L1D events which
are a better and more useful approximation despite ignoring instruction
traffic.

Reported-by: Alasdair Grant <alasdair.grant@arm.com>
Reported-by: Matt Horsnell <matt.horsnell@arm.com>
Reported-by: Michael Williams <michael.williams@arm.com>
Cc: stable@kernel.org
Cc: Jean Pihet <j-pihet@ti.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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wildea01 authored and Russell King committed Oct 15, 2011
1 parent 002ea9e commit 29a541f
Showing 1 changed file with 2 additions and 2 deletions.
4 changes: 2 additions & 2 deletions arch/arm/kernel/perf_event_v7.c
Expand Up @@ -321,8 +321,8 @@ static const unsigned armv7_a9_perf_map[PERF_COUNT_HW_MAX] = {
[PERF_COUNT_HW_CPU_CYCLES] = ARMV7_PERFCTR_CPU_CYCLES,
[PERF_COUNT_HW_INSTRUCTIONS] =
ARMV7_PERFCTR_INST_OUT_OF_RENAME_STAGE,
[PERF_COUNT_HW_CACHE_REFERENCES] = ARMV7_PERFCTR_COHERENT_LINE_HIT,
[PERF_COUNT_HW_CACHE_MISSES] = ARMV7_PERFCTR_COHERENT_LINE_MISS,
[PERF_COUNT_HW_CACHE_REFERENCES] = ARMV7_PERFCTR_DCACHE_ACCESS,
[PERF_COUNT_HW_CACHE_MISSES] = ARMV7_PERFCTR_DCACHE_REFILL,
[PERF_COUNT_HW_BRANCH_INSTRUCTIONS] = ARMV7_PERFCTR_PC_WRITE,
[PERF_COUNT_HW_BRANCH_MISSES] = ARMV7_PERFCTR_PC_BRANCH_MIS_PRED,
[PERF_COUNT_HW_BUS_CYCLES] = ARMV7_PERFCTR_CLOCK_CYCLES,
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