[PATCH 06/10] dma-buf/resv: stop pruning shared fences when exclusive is added

["Christian König" <ckoenig.leichtzumerken@gmail.com>]

First step towards new shared fence container implementation.

Signed-off-by: Christian König <christian.koenig@amd.com>
---
 drivers/dma-buf/dma-resv.c              | 16 +---------------
 drivers/gpu/drm/msm/msm_gem.c           | 14 ++++++--------
 drivers/gpu/drm/nouveau/nouveau_fence.c |  2 +-
 3 files changed, 8 insertions(+), 24 deletions(-)

diff --git a/drivers/dma-buf/dma-resv.c b/drivers/dma-buf/dma-resv.c
index 24adc32d36d4..d3a9a3bb15f0 100644
--- a/drivers/dma-buf/dma-resv.c
+++ b/drivers/dma-buf/dma-resv.c
@@ -271,32 +271,18 @@ EXPORT_SYMBOL(dma_resv_add_shared_fence);
 void dma_resv_add_excl_fence(struct dma_resv *obj, struct dma_fence *fence)
 {
 	struct dma_fence *old_fence = dma_resv_get_excl(obj);
-	struct dma_resv_list *old;
-	u32 i = 0;
 
 	dma_resv_assert_held(obj);
 
-	old = dma_resv_get_list(obj);
-	if (old)
-		i = old->shared_count;
-
-	if (fence)
-		dma_fence_get(fence);
+	dma_fence_get(fence);
 
 	preempt_disable();
 	write_seqcount_begin(&obj->seq);
 	/* write_seqcount_begin provides the necessary memory barrier */
 	RCU_INIT_POINTER(obj->fence_excl, fence);
-	if (old)
-		old->shared_count = 0;
 	write_seqcount_end(&obj->seq);
 	preempt_enable();
 
-	/* inplace update, no shared fences */
-	while (i--)
-		dma_fence_put(rcu_dereference_protected(old->shared[i],
-						dma_resv_held(obj)));
-
 	dma_fence_put(old_fence);
 }
 EXPORT_SYMBOL(dma_resv_add_excl_fence);
diff --git a/drivers/gpu/drm/msm/msm_gem.c b/drivers/gpu/drm/msm/msm_gem.c
index 348a7ad2c044..90e3dc3b927a 100644
--- a/drivers/gpu/drm/msm/msm_gem.c
+++ b/drivers/gpu/drm/msm/msm_gem.c
@@ -668,14 +668,12 @@ int msm_gem_sync_object(struct drm_gem_object *obj,
 	int i, ret;
 
 	fobj = dma_resv_get_list(obj->resv);
-	if (!fobj || (fobj->shared_count == 0)) {
-		fence = dma_resv_get_excl(obj->resv);
-		/* don't need to wait on our own fences, since ring is fifo */
-		if (fence && (fence->context != fctx->context)) {
-			ret = dma_fence_wait(fence, true);
-			if (ret)
-				return ret;
-		}
+	fence = dma_resv_get_excl(obj->resv);
+	/* don't need to wait on our own fences, since ring is fifo */
+	if (fence && (fence->context != fctx->context)) {
+		ret = dma_fence_wait(fence, true);
+		if (ret)
+			return ret;
 	}
 
 	if (!exclusive || !fobj)
diff --git a/drivers/gpu/drm/nouveau/nouveau_fence.c b/drivers/gpu/drm/nouveau/nouveau_fence.c
index 8df390078c85..42ddddbb49e4 100644
--- a/drivers/gpu/drm/nouveau/nouveau_fence.c
+++ b/drivers/gpu/drm/nouveau/nouveau_fence.c
@@ -350,7 +350,7 @@ nouveau_fence_sync(struct nouveau_bo *nvbo, struct nouveau_channel *chan, bool e
 	fobj = dma_resv_get_list(resv);
 	fence = dma_resv_get_excl(resv);
 
-	if (fence && (!exclusive || !fobj || !fobj->shared_count)) {
+	if (fence) {
 		struct nouveau_channel *prev = NULL;
 		bool must_wait = true;
 
-- 
2.17.1