Quoting Christian König (2018-03-16 14:22:32) [snip, probably lost too must context] > This allows for full grown pipelining, e.g. the exporter can say I need > to move the buffer for some operation. Then let the move operation wait > for all existing fences in the reservation object and install the fence > of the move operation as exclusive fence. Ok, the situation I have in mind is the non-pipelined case: revoking dma-buf for mmu_invalidate_range or shrink_slab. I would need a completion event that can be waited on the cpu for all the invalidate callbacks. (Essentially an atomic_t counter plus struct completion; a lighter version of dma_fence, I wonder where I've seen that before ;) Even so, it basically means passing a fence object down to the async callbacks for them to signal when they are complete. Just to handle the non-pipelined version. :| -Chris
