drm/i915/selftests: Flush tasklet on wait_for_submit()

Always flush the tasklet if we have pending submissions in
wait_for_submit(), so that even if we see the HW has started before we
process its ack, when we return the execlists state is well defined.

Fixes: 06289949b8dd ("drm/i915/selftests: Check for any sign of request starting in wait_for_submit()")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200218211215.1336341-1-chris@chris-wilson.co.uk

diff --git a/drivers/gpu/drm/i915/gt/selftest_lrc.c b/drivers/gpu/drm/i915/gt/selftest_lrc.c
index 7b303d5..a9c9cfb 100644 (file)
--- a/drivers/gpu/drm/i915/gt/selftest_lrc.c
+++ b/drivers/gpu/drm/i915/gt/selftest_lrc.c
@@ -77,11 +77,11 @@ static int wait_for_submit(struct intel_engine_cs *engine,
                cond_resched();
                intel_engine_flush_submission(engine);
 
-               if (i915_request_is_active(rq) &&
-                   !READ_ONCE(engine->execlists.pending[0])) {
-                       tasklet_unlock_wait(&engine->execlists.tasklet);
+               if (READ_ONCE(engine->execlists.pending[0]))
+                       continue;
+
+               if (i915_request_is_active(rq))
                        return 0;
-               }
 
                if (i915_request_started(rq)) /* that was quick! */
                        return 0;