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Patch "powerpc/perf: Add restrictions to PMC5 in power9 DD1" has been added to the 4.9-stable tree

PATCH [email protected] 1 participant 1 message Oct 19, 2017

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This is a note to let you know that I've just added the patch titled

powerpc/perf: Add restrictions to PMC5 in power9 DD1

to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
powerpc-perf-add-restrictions-to-pmc5-in-power9-dd1.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

Quoted 1 line

From foo@baz Thu Oct 19 15:04:02 CEST 2017

From: Madhavan Srinivasan <[email protected]>
Date: Sun, 12 Feb 2017 22:33:15 +0530
Subject: powerpc/perf: Add restrictions to PMC5 in power9 DD1

From: Madhavan Srinivasan <[email protected]>

[ Upstream commit 8d911904f3ce412b20874a9c95f82009dcbb007c ]

PMC5 on POWER9 DD1 may not provide right counts in all sampling scenarios, hence use PM_INST_DISP event instead in PMC2 or PMC3 in preference.

---
 arch/powerpc/perf/isa207-common.h |    4 ++++
 arch/powerpc/perf/power9-pmu.c    |    2 +-
 2 files changed, 5 insertions(+), 1 deletion(-)
arch/powerpc/perf/isa207-common.h +4 -0
@@ -201,6 +201,10 @@
 	CNST_PMC_VAL(1) | CNST_PMC_VAL(2) | CNST_PMC_VAL(3) | \
 	CNST_PMC_VAL(4) | CNST_PMC_VAL(5) | CNST_PMC_VAL(6) | CNST_NC_VAL
 
+/*
+ * Lets restrict use of PMC5 for instruction counting.
+ */
+#define P9_DD1_TEST_ADDER	(ISA207_TEST_ADDER | CNST_PMC_VAL(5))
 
 /* Bits in MMCR1 for PowerISA v2.07 */
 #define MMCR1_UNIT_SHIFT(pmc)		(60 - (4 * ((pmc) - 1)))
arch/powerpc/perf/power9-pmu.c +1 -1
@@ -295,7 +295,7 @@ static struct power_pmu power9_pmu = {
 	.name			= "POWER9",
 	.n_counter		= MAX_PMU_COUNTERS,
 	.add_fields		= ISA207_ADD_FIELDS,
-	.test_adder		= ISA207_TEST_ADDER,
+	.test_adder		= P9_DD1_TEST_ADDER,
 	.compute_mmcr		= isa207_compute_mmcr,
 	.config_bhrb		= power9_config_bhrb,
 	.bhrb_filter_map	= power9_bhrb_filter_map,

Patches currently in stable-queue which might be from [email protected] are

queue-4.9/powerpc-perf-add-restrictions-to-pmc5-in-power9-dd1.patch