Hey, op 21-01-14 16:17, Thomas Hellstrom schreef: > Maarten, for this and the other patches in this series, > > I seem to recall we have this discussion before? > IIRC I stated that reservation was a too heavy-weight lock to hold to > determine whether a buffer was idle? It's a pretty nasty thing to build in. > I've sent this patch after determining that this already didn't end up being heavyweight. Most places were already using the fence_lock and reservation, I just fixed up the few places that didn't hold a reservation while waiting. Converting the few places that didn't ended up being trivial, so I thought I'd submit it.
If a tryreserve fails it's a good indication that the buffer is NOT idle, no need to check the fences too in that case. I ended up converting this so I could use shared/exclusive fence slots internally in nouveau, allowing multiple readers to access the buffers in parallel. See commit "drm/nouveau: first stab at using shared fences for readable objects" at http://cgit.freedesktop.org/~mlankhorst/linux/log/ But doing this required killing fence_lock. ~Maarten
