On Wed, Oct 19, 2016 at 12:06 PM, Jan Ziak <0xe2.0x9a.0...@gmail.com> wrote: > This patch removes locks around reference counts in favor of atomic inc/dec > operations on the refcounts. This makes the refcount adjustments much faster.
I had the same idea last year and sent a patch series ([PATCH 00/13] mesa: Locking improvements and optimizations [1]). The part that corresponds to your patch are patches 5-9. 1-4, 10, and 11 were committed. I'm having a difficult time remembering why I ultimately dropped the series, but Ian's comment on 05/13 indicates that the locking is broken for bufferobj.c, so it's not appropriate to use atomics there. I remember that texture locking is totally broken, but I cannot remember the details. The other thing (in 12/13 [2]) is that vertex array objects, framebuffer objects, and pipeline objects are "container objects" and are not shared between contexts, so they require no locking. It would be better to solve that and avoid locking/atomics all together. But then FBOs (and renderbuffers?) from EXT_framebuffer_object and VAOs from APPLE_vertex_array_object are actually shared between contexts, so those are out as well. That seems to leave sampler objects, shader objects, and program objects. I suspect those are relatively small compared with textures or buffers. I'm not really sure what I'd suggest, to be honest. It seems like a lot of aggravation for a minimal reward if done right. [1] https://lists.freedesktop.org/archives/mesa-dev/2015-August/090972.html [2] https://lists.freedesktop.org/archives/mesa-dev/2015-August/090984.html _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/mesa-dev
