[Intel-gfx] [PATCH 18/26] drm/i915: use new iterator in i915_gem_object_last_write_engine v2

Christian König
2021-09-17T13:03:05Z

This is maybe even a fix since the RCU usage here looks incorrect.

v2: add missing rcu_read_lock()/unlock()

Signed-off-by: Christian König <christian.koenig@amd.com>
---
drivers/gpu/drm/i915/gem/i915_gem_object.h | 14 ++++++++------
1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_object.h b/drivers/gpu/drm/i915/gem/i915_gem_object.h
index 48112b9d76df..487329a96e92 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_object.h
+++ b/drivers/gpu/drm/i915/gem/i915_gem_object.h
@@ -507,16 +507,18 @@ static inline struct intel_engine_cs *
i915_gem_object_last_write_engine(struct drm_i915_gem_object *obj)
{
struct intel_engine_cs *engine = NULL;
+ struct dma_resv_iter cursor;
struct dma_fence *fence;

rcu_read_lock();
- fence = dma_resv_get_excl_unlocked(obj->base.resv);
+ dma_resv_iter_begin(&cursor, obj->base.resv, false);
+ dma_resv_for_each_fence_unlocked(&cursor, fence) {
+ if (fence && dma_fence_is_i915(fence) &&
+ !dma_fence_is_signaled(fence))
+ engine = to_request(fence)->engine;
+ }
+ dma_resv_iter_end(&cursor);
rcu_read_unlock();
-
- if (fence && dma_fence_is_i915(fence) && !dma_fence_is_signaled(fence))
- engine = to_request(fence)->engine;
- dma_fence_put(fence);
-
return engine;
}

--
2.25.1