[PATCH 5.18 072/181] perf arm-spe: Dont set data source if its not a memory operation

Greg Kroah-Hartman gregkh at linuxfoundation.org
Mon Jun 27 04:20:45 PDT 2022


From: Leo Yan <leo.yan at linaro.org>

[ Upstream commit 51ba539f5bdb5a8cc7b1dedd5e73ac54564a7602 ]

Except for memory load and store operations, ARM SPE records also can
support other operation types, bug when set the data source field the
current code assumes a record is a either load operation or store
operation, this leads to wrongly synthesize memory samples.

This patch strictly checks the record operation type, it only sets data
source only for the operation types ARM_SPE_LD and ARM_SPE_ST,
otherwise, returns zero for data source.  Therefore, we can synthesize
memory samples only when data source is a non-zero value, the function
arm_spe__is_memory_event() is useless and removed.

Fixes: e55ed3423c1bb29f ("perf arm-spe: Synthesize memory event")
Reviewed-by: Ali Saidi <alisaidi at amazon.com>
Reviewed-by: German Gomez <german.gomez at arm.com>
Signed-off-by: Leo Yan <leo.yan at linaro.org>
Tested-by: Ali Saidi <alisaidi at amazon.com>
Cc: Alexander Shishkin <alexander.shishkin at linux.intel.com>
Cc: alisaidi at amazon.com
Cc: Andrew Kilroy <andrew.kilroy at arm.com>
Cc: Benjamin Herrenschmidt <benh at kernel.crashing.org>
Cc: James Clark <james.clark at arm.com>
Cc: Jiri Olsa <jolsa at kernel.org>
Cc: John Garry <john.garry at huawei.com>
Cc: Kajol Jain <kjain at linux.ibm.com>
Cc: Leo Yan <leo.yan at linaro.org>
Cc: Li Huafei <lihuafei1 at huawei.com>
Cc: linux-arm-kernel at lists.infradead.org
Cc: Mark Rutland <mark.rutland at arm.com>
Cc: Mathieu Poirier <mathieu.poirier at linaro.org>
Cc: Namhyung Kim <namhyung at kernel.org>
Cc: Nick Forrington <nick.forrington at arm.com>
Cc: Peter Zijlstra <peterz at infradead.org>
Cc: Will Deacon <will at kernel.org>
Link: http://lore.kernel.org/lkml/20220517020326.18580-5-alisaidi@amazon.com
Signed-off-by: Arnaldo Carvalho de Melo <acme at redhat.com>
Signed-off-by: Sasha Levin <sashal at kernel.org>
---
 tools/perf/util/arm-spe.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/tools/perf/util/arm-spe.c b/tools/perf/util/arm-spe.c
index 1a80151baed9..d040406f3314 100644
--- a/tools/perf/util/arm-spe.c
+++ b/tools/perf/util/arm-spe.c
@@ -387,26 +387,16 @@ static int arm_spe__synth_instruction_sample(struct arm_spe_queue *speq,
 	return arm_spe_deliver_synth_event(spe, speq, event, &sample);
 }
 
-#define SPE_MEM_TYPE	(ARM_SPE_L1D_ACCESS | ARM_SPE_L1D_MISS | \
-			 ARM_SPE_LLC_ACCESS | ARM_SPE_LLC_MISS | \
-			 ARM_SPE_REMOTE_ACCESS)
-
-static bool arm_spe__is_memory_event(enum arm_spe_sample_type type)
-{
-	if (type & SPE_MEM_TYPE)
-		return true;
-
-	return false;
-}
-
 static u64 arm_spe__synth_data_source(const struct arm_spe_record *record)
 {
 	union perf_mem_data_src	data_src = { 0 };
 
 	if (record->op == ARM_SPE_LD)
 		data_src.mem_op = PERF_MEM_OP_LOAD;
-	else
+	else if (record->op == ARM_SPE_ST)
 		data_src.mem_op = PERF_MEM_OP_STORE;
+	else
+		return 0;
 
 	if (record->type & (ARM_SPE_LLC_ACCESS | ARM_SPE_LLC_MISS)) {
 		data_src.mem_lvl = PERF_MEM_LVL_L3;
@@ -510,7 +500,11 @@ static int arm_spe_sample(struct arm_spe_queue *speq)
 			return err;
 	}
 
-	if (spe->sample_memory && arm_spe__is_memory_event(record->type)) {
+	/*
+	 * When data_src is zero it means the record is not a memory operation,
+	 * skip to synthesize memory sample for this case.
+	 */
+	if (spe->sample_memory && data_src) {
 		err = arm_spe__synth_mem_sample(speq, spe->memory_id, data_src);
 		if (err)
 			return err;
-- 
2.35.1






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