drm/i915: Actually emit the await_start

Fix the inverted test to emit the wait on the end of the previous
request if we /haven't/ already.

Fixes: 6a79d848403d ("drm/i915: Lock signaler timeline while navigating")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: <stable@vger.kernel.org> # v5.5+
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200305104210.2619967-1-chris@chris-wilson.co.uk
(cherry picked from commit 07e9c59d63df6a1c44c1975c01827ba18b69270a)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

diff --git a/drivers/gpu/drm/i915/i915_request.c b/drivers/gpu/drm/i915/i915_request.c
index dcaa85a..468ca10 100644 (file)
--- a/drivers/gpu/drm/i915/i915_request.c
+++ b/drivers/gpu/drm/i915/i915_request.c
@@ -821,7 +821,7 @@ i915_request_await_start(struct i915_request *rq, struct i915_request *signal)
                return 0;
 
        err = 0;
-       if (intel_timeline_sync_is_later(i915_request_timeline(rq), fence))
+       if (!intel_timeline_sync_is_later(i915_request_timeline(rq), fence))
                err = i915_sw_fence_await_dma_fence(&rq->submit,
                                                    fence, 0,
                                                    I915_FENCE_GFP);