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No new users must be > + * implemented. > Consumers of a fence can instead notify themselves by > + * registering a callback on the fence. Mhm, the wait callback is transparent to consumers it's just that implementations used it for quite a number of different hacks. I would just drop that sentence. > */ > signed long (*wait)(struct dma_fence *fence, > bool intr, signed long timeout); > @@ -243,6 +249,8 @@ struct dma_fence_ops { > /** > * @release: > * > + * DEPRECATED! > + * > * Called on destruction of fence to release additional resources. > * Can be called from irq context. This callback is optional. If it is > * NULL, then dma_fence_free() is instead called as the default > @@ -254,6 +262,12 @@ struct dma_fence_ops { > * > * If the callback is implemented the memory backing the dma_fence > * object must be freed RCU safe. > + * > + * Deprecated because it prevents the producer of a fence from > + * unloading. No new users must be implemented. Parties with a > + * hypothetical need for this callback can instead simply and directly > + * perform their custom release operations one RCU grace period after > + * they have signaled the fence. Yeah that is a bit problematic. We need my patch set to explicit signal fences instead of returning true/false from callback for that so that a backend can properly implement this. It's on my TODO list, but not the highest priority at the moment. Regards, Christian. > */ > void (*release)(struct dma_fence *fence); > > > base-commit: 2302669bb4b52d581cc2589b90b3af7bb3783a28