[Intel-gfx] [PATCH i-g-t] i915/gem_ctx_engine: Prevent preemption

[Chris Wilson]

In order to pin the engine as busy, we have to prevent the kernel from
executing other independent work ahead of our plug, so tell the spinner
to not allow preemption.

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
---
 tests/i915/gem_ctx_engines.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/tests/i915/gem_ctx_engines.c b/tests/i915/gem_ctx_engines.c
index 3ecade417..d47cbdd7c 100644
--- a/tests/i915/gem_ctx_engines.c
+++ b/tests/i915/gem_ctx_engines.c
@@ -283,7 +283,8 @@ static void execute_one(int i915)
 
 			spin = igt_spin_new(i915,
 					    .ctx = param.ctx_id,
-					    .engine = 0);
+					    .engine = 0,
+					    .flags = IGT_SPIN_NO_PREEMPTION);
 
 			igt_debug("Testing with map of %d engines\n", i + 1);
 			memset(&engines.engines, -1, sizeof(engines.engines));
-- 
2.20.1