[PATCH 16/26] drm/i915: use new iterator in i915_gem_object_wait_reservation v2

[Christian König]

Simplifying the code a bit.

v2: add missing rcu read unlock.

Signed-off-by: Christian König <christian.koenig at amd.com>
---
 drivers/gpu/drm/i915/gem/i915_gem_wait.c | 57 +++++++-----------------
 1 file changed, 15 insertions(+), 42 deletions(-)

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_wait.c b/drivers/gpu/drm/i915/gem/i915_gem_wait.c
index f909aaa09d9c..a75dee9d7790 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_wait.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_wait.c
@@ -37,55 +37,28 @@ i915_gem_object_wait_reservation(struct dma_resv *resv,
 				 unsigned int flags,
 				 long timeout)
 {
-	struct dma_fence *excl;
-	bool prune_fences = false;
-
-	if (flags & I915_WAIT_ALL) {
-		struct dma_fence **shared;
-		unsigned int count, i;
-		int ret;
-
-		ret = dma_resv_get_fences(resv, &excl, &count, &shared);
-		if (ret)
-			return ret;
-
-		for (i = 0; i < count; i++) {
-			timeout = i915_gem_object_wait_fence(shared[i],
-							     flags, timeout);
-			if (timeout < 0)
-				break;
-
-			dma_fence_put(shared[i]);
+	struct dma_resv_iter cursor;
+	struct dma_fence *fence;
+
+	rcu_read_lock();
+	dma_resv_for_each_fence_unlocked(resv, &cursor, flags & I915_WAIT_ALL,
+					 fence) {
+
+		rcu_read_unlock();
+		timeout = i915_gem_object_wait_fence(fence, flags, timeout);
+		rcu_read_lock();
+		if (timeout < 0) {
+			dma_fence_put(fence);
+			break;
 		}
-
-		for (; i < count; i++)
-			dma_fence_put(shared[i]);
-		kfree(shared);
-
-		/*
-		 * If both shared fences and an exclusive fence exist,
-		 * then by construction the shared fences must be later
-		 * than the exclusive fence. If we successfully wait for
-		 * all the shared fences, we know that the exclusive fence
-		 * must all be signaled. If all the shared fences are
-		 * signaled, we can prune the array and recover the
-		 * floating references on the fences/requests.
-		 */
-		prune_fences = count && timeout >= 0;
-	} else {
-		excl = dma_resv_get_excl_unlocked(resv);
 	}
-
-	if (excl && timeout >= 0)
-		timeout = i915_gem_object_wait_fence(excl, flags, timeout);
-
-	dma_fence_put(excl);
+	rcu_read_unlock();
 
 	/*
 	 * Opportunistically prune the fences iff we know they have *all* been
 	 * signaled.
 	 */
-	if (prune_fences)
+	if (timeout > 0)
 		dma_resv_prune(resv);
 
 	return timeout;
-- 
2.25.1