Add a new dma_resv_prune_fences() function to improve memory management.
v2: fix potential NULL deref
Signed-off-by: Christian König christian.koenig@amd.com --- drivers/dma-buf/dma-resv.c | 37 ++++++++++++++++++++++ drivers/gpu/drm/i915/gem/i915_gem_wait.c | 3 +- drivers/gpu/drm/i915/i915_gem_batch_pool.c | 2 +- drivers/gpu/drm/i915/i915_vma.c | 3 +- drivers/gpu/drm/ttm/ttm_bo.c | 2 +- include/linux/dma-resv.h | 1 + 6 files changed, 42 insertions(+), 6 deletions(-)
diff --git a/drivers/dma-buf/dma-resv.c b/drivers/dma-buf/dma-resv.c index 42a8f3f11681..59fbcd9f4b01 100644 --- a/drivers/dma-buf/dma-resv.c +++ b/drivers/dma-buf/dma-resv.c @@ -301,6 +301,43 @@ void dma_resv_add_excl_fence(struct dma_resv *obj, struct dma_fence *fence) } EXPORT_SYMBOL(dma_resv_add_excl_fence);
+/** + * dma_resv_prune_fences - prune signaled fences from the resv object + * @obj: the reservation object to prune + * + * Prune all signaled fences from the reservation object. + */ +void dma_resv_prune_fences(struct dma_resv *obj) +{ + struct dma_resv_list *list; + struct dma_fence *fence; + unsigned int i; + + dma_resv_assert_held(obj); + + fence = dma_resv_get_excl(obj); + if (fence && dma_fence_is_signaled(fence)) { + RCU_INIT_POINTER(obj->fence_excl, NULL); + dma_fence_put(fence); + } + + list = dma_resv_get_list(obj); + if (!list) + return; + + for (i = 0; i < list->shared_count; ++i) { + fence = rcu_dereference_protected(list->shared[i], + dma_resv_held(obj)); + + if (!dma_fence_is_signaled(fence)) + continue; + + RCU_INIT_POINTER(list->shared[i], dma_fence_get_stub()); + dma_fence_put(fence); + } +} +EXPORT_SYMBOL(dma_resv_prune_fences); + /** * dma_resv_copy_fences - Copy all fences from src to dst. * @dst: the destination reservation object diff --git a/drivers/gpu/drm/i915/gem/i915_gem_wait.c b/drivers/gpu/drm/i915/gem/i915_gem_wait.c index 8af55cd3e690..a76d36f8fb77 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_wait.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_wait.c @@ -85,8 +85,7 @@ i915_gem_object_wait_reservation(struct dma_resv *resv, * signaled. */ if (prune_fences && dma_resv_trylock(resv)) { - if (dma_resv_test_signaled_rcu(resv, true)) - dma_resv_add_excl_fence(resv, NULL); + dma_resv_prune_fences(resv); dma_resv_unlock(resv); }
diff --git a/drivers/gpu/drm/i915/i915_gem_batch_pool.c b/drivers/gpu/drm/i915/i915_gem_batch_pool.c index 5f82a763e64c..274cf5b19fc9 100644 --- a/drivers/gpu/drm/i915/i915_gem_batch_pool.c +++ b/drivers/gpu/drm/i915/i915_gem_batch_pool.c @@ -114,7 +114,7 @@ i915_gem_batch_pool_get(struct i915_gem_batch_pool *pool, */ if (rcu_access_pointer(resv->fence)) { dma_resv_lock(resv, NULL); - dma_resv_add_excl_fence(resv, NULL); + dma_resv_prune_fences(resv); dma_resv_unlock(resv); } } diff --git a/drivers/gpu/drm/i915/i915_vma.c b/drivers/gpu/drm/i915/i915_vma.c index ebfd03d117cd..fcbe433a968c 100644 --- a/drivers/gpu/drm/i915/i915_vma.c +++ b/drivers/gpu/drm/i915/i915_vma.c @@ -100,8 +100,7 @@ static void __i915_vma_retire(struct i915_active *ref)
/* Prune the shared fence arrays iff completely idle (inc. external) */ if (dma_resv_trylock(obj->base.resv)) { - if (dma_resv_test_signaled_rcu(obj->base.resv, true)) - dma_resv_add_excl_fence(obj->base.resv, NULL); + dma_resv_prune_fences(obj->base.resv); dma_resv_unlock(obj->base.resv); }
diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c index 58d1f2b28132..f78f52cc2e6d 100644 --- a/drivers/gpu/drm/ttm/ttm_bo.c +++ b/drivers/gpu/drm/ttm/ttm_bo.c @@ -1818,7 +1818,7 @@ int ttm_bo_wait(struct ttm_buffer_object *bo, if (timeout == 0) return -EBUSY;
- dma_resv_add_excl_fence(bo->base.resv, NULL); + dma_resv_prune_fences(bo->base.resv); return 0; } EXPORT_SYMBOL(ttm_bo_wait); diff --git a/include/linux/dma-resv.h b/include/linux/dma-resv.h index ee50d10f052b..03b0f95682b0 100644 --- a/include/linux/dma-resv.h +++ b/include/linux/dma-resv.h @@ -279,6 +279,7 @@ int dma_resv_reserve_shared(struct dma_resv *obj, unsigned int num_fences); void dma_resv_add_shared_fence(struct dma_resv *obj, struct dma_fence *fence);
void dma_resv_add_excl_fence(struct dma_resv *obj, struct dma_fence *fence); +void dma_resv_prune_fences(struct dma_resv *obj);
int dma_resv_get_fences_rcu(struct dma_resv *obj, struct dma_fence **pfence_excl,