Commit 9736387a authored by Chris Wilson's avatar Chris Wilson
Browse files

drm/i915: Reduce test_and_set_bit to set_bit in i915_request_submit() 



Avoid the full blown memory barrier of test_and_set_bit() by noting the
completed request and removing it from the lists.

Signed-off-by: default avatarChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: default avatarAndi Shyti <andi.shyti@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210114135612.13210-5-chris@chris-wilson.co.uk
parent 2d60d3e0

drivers/gpu/drm/i915/i915_request.c

+9 −7
Original line number Diff line number Diff line
@@ -551,8 +551,10 @@ bool __i915_request_submit(struct i915_request *request) 
	 * dropped upon retiring. (Otherwise if resubmit a *retired*

	 * request, this would be a horrible use-after-free.)

	 */

	if (__i915_request_is_complete(request))

		goto xfer;

	if (__i915_request_is_complete(request)) {

		list_del_init(&request->sched.link);

		goto active;

	}



	if (unlikely(intel_context_is_banned(request->context)))

		i915_request_set_error_once(request, -EIO);
@@ -587,11 +589,11 @@ bool __i915_request_submit(struct i915_request *request) 
	engine->serial++;

	result = true;



xfer:

	if (!test_and_set_bit(I915_FENCE_FLAG_ACTIVE, &request->fence.flags)) {

	GEM_BUG_ON(test_bit(I915_FENCE_FLAG_ACTIVE, &request->fence.flags));

	list_move_tail(&request->sched.link, &engine->active.requests);

active:

	clear_bit(I915_FENCE_FLAG_PQUEUE, &request->fence.flags);

	}

	set_bit(I915_FENCE_FLAG_ACTIVE, &request->fence.flags);



	/*

	 * XXX Rollback bonded-execution on __i915_request_unsubmit()?