[SRU][N:gke][PATCH 078/106] perf arm-spe: Introduce arm_spe__is_homogeneous()

[Tim Whisonant]

From: Leo Yan <leo.yan at arm.com>

BugLink: https://bugs.launchpad.net/bugs/2117098

Introduce the arm_spe__is_homogeneous() function, it uses to check if
Arm SPE is homogeneous cross all CPUs.

Signed-off-by: Leo Yan <leo.yan at arm.com>
Reviewed-by: James Clark <james.clark at linaro.org>
Link: https://lore.kernel.org/r/20241003185322.192357-4-leo.yan@arm.com
Signed-off-by: Namhyung Kim <namhyung at kernel.org>
(cherry picked from commit 56ae663e7636f2ce180201f0f18d7736c319a43f)
Signed-off-by: Tim Whisonant <tim.whisonant at canonical.com>
---
 tools/perf/util/arm-spe.c | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/tools/perf/util/arm-spe.c b/tools/perf/util/arm-spe.c
index 29be702cd096b..5dd8dfc37e054 100644
--- a/tools/perf/util/arm-spe.c
+++ b/tools/perf/util/arm-spe.c
@@ -82,6 +82,7 @@ struct arm_spe {
 	u64				**metadata;
 	u64				metadata_ver;
 	u64				metadata_nr_cpu;
+	bool				is_homogeneous;
 };
 
 struct arm_spe_queue {
@@ -1359,6 +1360,30 @@ arm_spe_synth_events(struct arm_spe *spe, struct perf_session *session)
 	return 0;
 }
 
+static bool arm_spe__is_homogeneous(u64 **metadata, int nr_cpu)
+{
+	u64 midr;
+	int i;
+
+	if (!nr_cpu)
+		return false;
+
+	for (i = 0; i < nr_cpu; i++) {
+		if (!metadata[i])
+			return false;
+
+		if (i == 0) {
+			midr = metadata[i][ARM_SPE_CPU_MIDR];
+			continue;
+		}
+
+		if (midr != metadata[i][ARM_SPE_CPU_MIDR])
+			return false;
+	}
+
+	return true;
+}
+
 int arm_spe_process_auxtrace_info(union perf_event *event,
 				  struct perf_session *session)
 {
@@ -1404,6 +1429,7 @@ int arm_spe_process_auxtrace_info(union perf_event *event,
 	spe->metadata = metadata;
 	spe->metadata_ver = metadata_ver;
 	spe->metadata_nr_cpu = nr_cpu;
+	spe->is_homogeneous = arm_spe__is_homogeneous(metadata, nr_cpu);
 
 	spe->timeless_decoding = arm_spe__is_timeless_decoding(spe);
 
-- 
2.43.0