drm/i915/gem: Remove redundant exec_fence

Since there can only be one of in_fence/exec_fence, just use the single
in_fence local.

v2: Consolidate lookup
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200513180937.28992-1-chris@chris-wilson.co.uk

drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c

@@ -2622,7 +2622,6 @@ i915_gem_do_execbuffer(struct drm_device *dev,
 	struct drm_i915_private *i915 = to_i915(dev);
 	struct i915_execbuffer eb;
 	struct dma_fence *in_fence = NULL;
-	struct dma_fence *exec_fence = NULL;
 	struct sync_file *out_fence = NULL;
 	struct i915_vma *batch;
 	int out_fence_fd = -1;
@@ -2665,30 +2664,22 @@ i915_gem_do_execbuffer(struct drm_device *dev,
 	if (args->flags & I915_EXEC_IS_PINNED)
 		eb.batch_flags |= I915_DISPATCH_PINNED;
 
-	if (args->flags & I915_EXEC_FENCE_IN) {
+#define IN_FENCES (I915_EXEC_FENCE_IN | I915_EXEC_FENCE_SUBMIT)
+	if (args->flags & IN_FENCES) {
+		if ((args->flags & IN_FENCES) == IN_FENCES)
+			return -EINVAL;
+
 		in_fence = sync_file_get_fence(lower_32_bits(args->rsvd2));
 		if (!in_fence)
 			return -EINVAL;
 	}
-
-	if (args->flags & I915_EXEC_FENCE_SUBMIT) {
-		if (in_fence) {
-			err = -EINVAL;
-			goto err_in_fence;
-		}
-
-		exec_fence = sync_file_get_fence(lower_32_bits(args->rsvd2));
-		if (!exec_fence) {
-			err = -EINVAL;
-			goto err_in_fence;
-		}
-	}
+#undef IN_FENCES
 
 	if (args->flags & I915_EXEC_FENCE_OUT) {
 		out_fence_fd = get_unused_fd_flags(O_CLOEXEC);
 		if (out_fence_fd < 0) {
 			err = out_fence_fd;
-			goto err_exec_fence;
+			goto err_in_fence;
 		}
 	}
 
@@ -2779,14 +2770,13 @@ i915_gem_do_execbuffer(struct drm_device *dev,
 	}
 
 	if (in_fence) {
-		err = i915_request_await_dma_fence(eb.request, in_fence);
-		if (err < 0)
-			goto err_request;
-	}
-
-	if (exec_fence) {
-		err = i915_request_await_execution(eb.request, exec_fence,
-						   eb.engine->bond_execute);
+		if (args->flags & I915_EXEC_FENCE_SUBMIT)
+			err = i915_request_await_execution(eb.request,
+							   in_fence,
+							   eb.engine->bond_execute);
+		else
+			err = i915_request_await_dma_fence(eb.request,
+							   in_fence);
 		if (err < 0)
 			goto err_request;
 	}
@@ -2855,8 +2845,6 @@ i915_gem_do_execbuffer(struct drm_device *dev,
 err_out_fence:
 	if (out_fence_fd != -1)
 		put_unused_fd(out_fence_fd);
-err_exec_fence:
-	dma_fence_put(exec_fence);
 err_in_fence:
 	dma_fence_put(in_fence);
 	return err;