[Intel-gfx] [PATCH 2/3] drm/i915/selftests: Flush the preemption request before waiting

[Chris Wilson]

Make sure that the request has been submitted to HW before we begin our
wait. This reduces our reliance on the semaphore yield interrupt driving
the preemption request.

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/gt/selftest_lrc.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/gpu/drm/i915/gt/selftest_lrc.c b/drivers/gpu/drm/i915/gt/selftest_lrc.c
index 6f21cdfd0903..6b069bb1ddcc 100644
--- a/drivers/gpu/drm/i915/gt/selftest_lrc.c
+++ b/drivers/gpu/drm/i915/gt/selftest_lrc.c
@@ -607,6 +607,10 @@ static int __live_lrc_gpr(struct intel_engine_cs *engine,
 		err = emit_semaphore_signal(engine->kernel_context, slot);
 		if (err)
 			goto err_rq;
+
+		err = wait_for_submit(engine, rq, HZ / 2);
+		if (err)
+			goto err_rq;
 	} else {
 		slot[0] = 1;
 		wmb();
-- 
2.20.1