[PATCH i-g-t v4] tests/intel/xe_pmu: Skip tests if the engine-active-ticks event is not present

[Soham Purkait]

Skip the tests and subtests involving the engine activity if the
engine-active-ticks event is not present for the respective
device.

v1:
 - Add a variable has_engine_active_ticks to check for the
   existence of engine-active-ticks event. (Riana)
v2:
 - Refactor commit title. (Jakub)
v3:
 - Add generic function has_event. (Riana)

Signed-off-by: Soham Purkait <soham.purkait at intel.com>
---
 tests/intel/xe_pmu.c | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/tests/intel/xe_pmu.c b/tests/intel/xe_pmu.c
index 0e5a7360f..a98fba5a4 100644
--- a/tests/intel/xe_pmu.c
+++ b/tests/intel/xe_pmu.c
@@ -106,6 +106,7 @@ const double tolerance = 0.1;
 static char xe_device[NAME_MAX];
 static bool autoprobe;
 static int total_exec_quantum;
+static bool has_engine_active_ticks;
 
 #define test_each_engine(test, fd, hwe) \
 	igt_subtest_with_dynamic(test) \
@@ -113,6 +114,17 @@ static int total_exec_quantum;
 			igt_dynamic_f("engine-%s%d", xe_engine_class_string(hwe->engine_class), \
 				      hwe->engine_instance)
 
+static bool has_event(const char *device, const char *event)
+{
+	char buf[512];
+
+	snprintf(buf, sizeof(buf),
+		 "/sys/bus/event_source/devices/%s/events/%s",
+		 device,
+		 event);
+	return (!!access(buf, F_OK));
+}
+
 static int open_pmu(int xe, uint64_t config)
 {
 	int fd;
@@ -191,6 +203,8 @@ static uint64_t get_event_config(unsigned int gt, struct drm_xe_engine_class_ins
 	uint64_t pmu_config = 0;
 	int ret;
 
+	igt_skip_on(has_engine_active_ticks);
+
 	ret = perf_event_config(xe_device, event, &pmu_config);
 	igt_assert(ret >= 0);
 	pmu_config |= add_format_config("gt", gt);
@@ -907,6 +921,7 @@ igt_main
 		fd = drm_open_driver(DRIVER_XE);
 		xe_perf_device(fd, xe_device, sizeof(xe_device));
 		num_engines = xe_number_engines(fd);
+		has_engine_active_ticks = has_event(xe_device, "engine-active-ticks");
 	}
 
 	igt_describe("Validate PMU gt-c6 residency counters when idle");
-- 
2.34.1