[PATCH 09/16] drm/i915: Trim the retired request queue after submitting

[Chris Wilson]

If we submit a request and see that the previous request on this
timeline was already signaled, we first do not need to add the
dependency tracker for that completed request and secondly we know that
we there is then a large backlog in retiring requests affecting this
timeline. Given that we just submitted more work to the HW, now would be
a good time to catch up on those retirements.

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen at linux.intel.com>
---
 drivers/gpu/drm/i915/i915_gem_request.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/i915_gem_request.c b/drivers/gpu/drm/i915/i915_gem_request.c
index 94429405e776..4107ee4afd83 100644
--- a/drivers/gpu/drm/i915/i915_gem_request.c
+++ b/drivers/gpu/drm/i915/i915_gem_request.c
@@ -1021,7 +1021,7 @@ void __i915_add_request(struct drm_i915_gem_request *request, bool flush_caches)
 
 	prev = i915_gem_active_raw(&timeline->last_request,
 				   &request->i915->drm.struct_mutex);
-	if (prev) {
+	if (prev && !i915_gem_request_completed(prev)) {
 		i915_sw_fence_await_sw_fence(&request->submit, &prev->submit,
 					     &request->submitq);
 		if (engine->schedule)
@@ -1057,6 +1057,9 @@ void __i915_add_request(struct drm_i915_gem_request *request, bool flush_caches)
 	local_bh_disable();
 	i915_sw_fence_commit(&request->submit);
 	local_bh_enable(); /* Kick the execlists tasklet if just scheduled */
+
+	if (prev && i915_gem_request_completed(prev))
+		i915_gem_request_retire_upto(prev);
 }
 
 static unsigned long local_clock_us(unsigned int *cpu)
-- 
2.15.1