drm/i915: Immediately process a reset before starting waiting

As we handoff the GPU reset to the waiter, we need to check we don't
miss a wakeup if it has already been sent prior to us starting the wait.

v2: Tweak checking for reset to be clear to the need before sleeping
after changing the task state.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/20170223074422.4125-16-chris@chris-wilson.co.uk
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

drivers/gpu/drm/i915/i915_gem_request.c

@@ -1126,6 +1126,9 @@ long i915_wait_request(struct drm_i915_gem_request *req,
 		 */
 		goto wakeup;
 
+	if (flags & I915_WAIT_LOCKED)
+		__i915_wait_request_check_and_reset(req);
+
 	for (;;) {
 		if (signal_pending_state(state, current)) {
 			timeout = -ERESTARTSYS;