[PATCH v4 1/6] perf arm_spe: Make a function to get the MIDR

James Clark james.clark at linaro.org
Tue Apr 14 05:47:59 PDT 2026


We'll need the MIDR to dump IMPDEF events in the next commits so extract
a function for it.

No functional changes intended.

Reviewed-by: Leo Yan <leo.yan at arm.com>
Signed-off-by: James Clark <james.clark at linaro.org>
---
 tools/perf/util/arm-spe.c | 36 ++++++++++++++++++++++--------------
 1 file changed, 22 insertions(+), 14 deletions(-)

diff --git a/tools/perf/util/arm-spe.c b/tools/perf/util/arm-spe.c
index e5835042acdf7685f95e19665cd45f97ed868275..39046033e1433cff82ef0668074867aba4a462a4 100644
--- a/tools/perf/util/arm-spe.c
+++ b/tools/perf/util/arm-spe.c
@@ -972,14 +972,9 @@ static void arm_spe__synth_memory_level(struct arm_spe_queue *speq,
 	}
 }
 
-static void arm_spe__synth_ds(struct arm_spe_queue *speq,
-			      const struct arm_spe_record *record,
-			      union perf_mem_data_src *data_src)
+static int arm_spe__get_midr(struct arm_spe *spe, int cpu, u64 *midr)
 {
-	struct arm_spe *spe = speq->spe;
-	u64 *metadata = NULL;
-	u64 midr;
-	unsigned int i;
+	u64 *metadata;
 
 	/* Metadata version 1 assumes all CPUs are the same (old behavior) */
 	if (spe->metadata_ver == 1) {
@@ -987,15 +982,28 @@ static void arm_spe__synth_ds(struct arm_spe_queue *speq,
 
 		pr_warning_once("Old SPE metadata, re-record to improve decode accuracy\n");
 		cpuid = perf_env__cpuid(perf_session__env(spe->session));
-		midr = strtol(cpuid, NULL, 16);
-	} else {
-		metadata = arm_spe__get_metadata_by_cpu(spe, speq->cpu);
-		if (!metadata)
-			return;
-
-		midr = metadata[ARM_SPE_CPU_MIDR];
+		*midr = strtol(cpuid, NULL, 16);
+		return 0;
 	}
 
+	metadata = arm_spe__get_metadata_by_cpu(spe, cpu);
+	if (!metadata)
+		return -EINVAL;
+
+	*midr = metadata[ARM_SPE_CPU_MIDR];
+	return 0;
+}
+
+static void arm_spe__synth_ds(struct arm_spe_queue *speq,
+			      const struct arm_spe_record *record,
+			      union perf_mem_data_src *data_src)
+{
+	u64 midr;
+	unsigned int i;
+
+	if (arm_spe__get_midr(speq->spe, speq->cpu, &midr))
+		return;
+
 	for (i = 0; i < ARRAY_SIZE(data_source_handles); i++) {
 		if (is_midr_in_range_list(midr, data_source_handles[i].midr_ranges)) {
 			return data_source_handles[i].ds_synth(record, data_src);

-- 
2.34.1




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