perf test: Extend branch stack sampling test for Arm64 BRBE

BRBE emits IRQ and ERET branches for branching and returning from
trapped instructions. Add a test that loops on a trapped instruction
(MRS - Read special register) for this.

Extend the expected 'any_call' branches to include FAULT_DATA and
FAULT_INST as these are emitted by BRBE.

Reviewed-by: Ian Rogers <irogers@google.com>
Co-developed-by: German Gomez <german.gomez@arm.com>
Signed-off-by: German Gomez <german.gomez@arm.com>
Signed-off-by: James Clark <james.clark@linaro.org>
Cc: Adam Young <admiyo@os.amperecomputing.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rob Herring <robh@kernel.org>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

2 files changed, 33 insertions, 0 deletions

diff --git a/tools/perf/tests/workloads/Build b/tools/perf/tests/workloads/Build
index 5af17206f04d..fb1012cc4fc3 100644
--- a/tools/perf/tests/workloads/Build
+++ b/tools/perf/tests/workloads/Build
@@ -7,8 +7,10 @@ perf-test-y += sqrtloop.o
 perf-test-y += brstack.o
 perf-test-y += datasym.o
 perf-test-y += landlock.o
+perf-test-y += traploop.o
 
 CFLAGS_sqrtloop.o         = -g -O0 -fno-inline -U_FORTIFY_SOURCE
 CFLAGS_leafloop.o         = -g -O0 -fno-inline -fno-omit-frame-pointer -U_FORTIFY_SOURCE
 CFLAGS_brstack.o          = -g -O0 -fno-inline -U_FORTIFY_SOURCE
 CFLAGS_datasym.o          = -g -O0 -fno-inline -U_FORTIFY_SOURCE
+CFLAGS_traploop.o         = -g -O0 -fno-inline -U_FORTIFY_SOURCE
diff --git a/tools/perf/tests/workloads/traploop.c b/tools/perf/tests/workloads/traploop.c
new file mode 100644
index 000000000000..68dec399a735
--- /dev/null
+++ b/tools/perf/tests/workloads/traploop.c
@@ -0,0 +1,31 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <stdlib.h>
+#include "../tests.h"
+
+#define BENCH_RUNS 999999
+
+#ifdef __aarch64__
+static void trap_bench(void)
+{
+	unsigned long val;
+
+	asm("mrs %0, ID_AA64ISAR0_EL1" : "=r" (val));   /* TRAP + ERET */
+}
+#else
+static void trap_bench(void) { }
+#endif
+
+static int traploop(int argc, const char **argv)
+{
+	int num_loops = BENCH_RUNS;
+
+	if (argc > 0)
+		num_loops = atoi(argv[0]);
+
+	for (int i = 0; i < num_loops; i++)
+		trap_bench();
+
+	return 0;
+}
+
+DEFINE_WORKLOAD(traploop);