On Fri, Sep 26, 2014 at 3:04 PM, Alex Deucher <alexdeuc...@gmail.com> wrote: > On Thu, Sep 25, 2014 at 3:02 PM, Tom Stellard <t...@stellard.net> wrote: >> On Mon, Sep 22, 2014 at 09:48:43PM +0200, Marek Olšák wrote: >>> No, we cannot detect compute-only contexts yet. We need to add a new >>> parameter to pipe_context::context_create which says that a context is >>> compute-only. That should be OpenCL but not OpenGL. >>> >>> Also, some code paths like resource_copy_region use the graphics >>> engine for copying, which cannot be used with compute rings and must >>> be implemented with either DMA or compute-based blits. DMA isn't >>> flexible enough, so some additional work for compute-based blits might >>> be needed. We can also use the graphics ring for copying only and the >>> compute ring for compute stuff. >>> >> >> If possible, I think I would prefer continuing to use the graphic ring >> for blits and only submit compute specific packets to the compute ring. >> I'm a little concerned that adding a compute-flag to context create >> might make it harder to share code between compute and graphics, which >> I think is important. >> >> What are the downsides of using both rings at once? Will we need to add >> synchronization code for the two rings? I think the last time I >> looked into doing this, the biggest problem was that fences were >> submitted via the graphics ring even though they were meant for jobs >> on the compute ring. Is there are good solution to this? > > It would be nice to not have any dependencies on the gfx ring. That > way compute jobs can run on the compute rings without requiring the > gfx ring which should avoid any latency issues with desktop gfx jobs.
In that case we have to rewrite resource_copy_region and make it use compute shaders only. The ideal time for that would be after ARB_compute_shader (from GL4.3) has been implemented. Marek _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev
