On Mon, Aug 8, 2011 at 7:56 PM, Alex Deucher <alexdeuc...@gmail.com> wrote: > On Sun, Aug 7, 2011 at 5:25 PM, Marek Olšák <mar...@gmail.com> wrote: >> Hi, >> >> I have been recently trying to get thread offloading of the CS ioctl >> into r600g in order to reduce the impact of kernel overhead on fps. >> That, unfortunately, requires whole winsys/radeon to be used, because >> even the buffer management (bo_map, bo_wait, bo_busy) must take into >> account that a CS ioctl may be in progress. Besides that, there are >> several possible race conditions in r600g, so instead of rewriting >> r600g and trying to do what winsys/radeon is doing, I decided to >> simply use winsys/radeon. >> >> What's new in r600g: >> - Thread offloading of the DRM CS ioctl. I expect 0-15% increase in >> performance from that in CPU-bound apps. >> - The new GEM_WAIT ioctl is used to avoid waiting for a buffer when >> possible. (e.g. Mesa may map an index buffer to compute index bounds, >> which shouldn't cause unnecessary waiting now) I have sent the DRM >> patches which add the ioctl to dri-devel. >> - Thread-safety: There are several possible races in r600g. I >> especially don't like radeon_bo::reloc, which may cause pretty ugly >> races if a resource is shared and relocated in multiple contexts. >> winsys/radeon doesn't have that race and also fixes a couple more. >> Hopefully this thread-safeness won't cause performance regressions. >> >> winsys/radeon can do space checking as well, but we don't use that in r600g >> yet. >> >> Performance improvements - I have been able to find a difference with >> these apps: >> >> Unigine Heaven >> Before: 7.3 fps >> After: 7.6 fps >> >> Torcs >> Before: 29 fps >> After: 34 fps >> >> Note that every commit in the r600winsys2 branch has been committed >> without piglit regressions, so that we can bisect through it if >> needed. The net loss is a little over 900 lines of code in r600g. The >> fenced cache buffer manager in r600g has turned out not to be superior >> to pb_cache_bufmgr with the is_buffer_busy hook set, so I removed the >> former too, as the latter is way simpler. >> >> This new work has been pushed into a new branch r600winsys2 in the >> main Mesa repository, please review/test. >> > > Looks good. I'll try and run some tests on various hw later this week.
I ran this on a few cards today and all seems well. Alex > > Reviewed-by: Alex Deucher <alexander.deuc...@amd.com> > > >> Marek >> _______________________________________________ >> mesa-dev mailing list >> mesa-dev@lists.freedesktop.org >> http://lists.freedesktop.org/mailman/listinfo/mesa-dev >> > _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev
