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powerpc/perf: Fix thresholding counter data for unknown type

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[ Upstream commit 17cfccc915 ]

MMCRA[34:36] and MMCRA[38:44] expose the thresholding counter value.
Thresholding counter can be used to count latency cycles such as
load miss to reload. But threshold counter value is not relevant
when the sampled instruction type is unknown or reserved. Patch to
fix the thresholding counter value to zero when sampled instruction
type is unknown or reserved.

Fixes: 170a315f41c6('powerpc/perf: Support to export MMCRA[TEC*] field to userspace')
Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Madhavan Srinivasan 2018-12-09 14:48:15 +05:30 • committed by Greg Kroah-Hartman
commit 5a0c7fb533
1 changed files with 6 additions and 1 deletions
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7
arch/powerpc/perf/isa207-common.c
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@ -226,8 +226,13 @@ void isa207_get_mem_weight(u64 *weight)
u64 mmcra = mfspr(SPRN_MMCRA);
u64 exp = MMCRA_THR_CTR_EXP(mmcra);
u64 mantissa = MMCRA_THR_CTR_MANT(mmcra);
u64 sier = mfspr(SPRN_SIER);
u64 val = (sier & ISA207_SIER_TYPE_MASK) >> ISA207_SIER_TYPE_SHIFT;
*weight = mantissa << (2 * exp);
if (val == 0 || val == 7)
*weight = 0;
else
*weight = mantissa << (2 * exp);
}
int isa207_get_constraint(u64 event, unsigned long *maskp, unsigned long *valp)