[Intel-gfx] [PATCH] drm/i915/selftests: Skip unstable timing measurements

[Chris Wilson]

If any of the perf tests run into 0 time, not only are we liable to
divide by zero, but the result would be highly questionable.
Nevertheless, let's not have a div-by-zero error.

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/selftests/intel_memory_region.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/i915/selftests/intel_memory_region.c b/drivers/gpu/drm/i915/selftests/intel_memory_region.c
index 75839db63bea..59c58a276677 100644
--- a/drivers/gpu/drm/i915/selftests/intel_memory_region.c
+++ b/drivers/gpu/drm/i915/selftests/intel_memory_region.c
@@ -852,6 +852,9 @@ static int _perf_memcpy(struct intel_memory_region *src_mr,
 		}
 
 		sort(t, ARRAY_SIZE(t), sizeof(*t), wrap_ktime_compare, NULL);
+		if (!t[0])
+			continue;
+
 		pr_info("%s src(%s, %s) -> dst(%s, %s) %14s %4llu KiB copy: %5lld MiB/s\n",
 			__func__,
 			src_mr->name,
-- 
2.20.1