On Tue, 5 Aug 2014 18:08:16 +0200 Daniel Vetter <daniel@xxxxxxxx> wrote: > On Tue, Aug 5, 2014 at 6:05 PM, Jesse Barnes <jbarnes@xxxxxxxxxxxxxxxx> wrote: > > On Tue, 5 Aug 2014 17:08:22 +0200 > > Daniel Vetter <daniel@xxxxxxxx> wrote: > > > >> On Tue, Aug 5, 2014 at 4:59 PM, Jesse Barnes <jbarnes@xxxxxxxxxxxxxxxx> wrote: > >> >> This doesn't really look like the interface I'd expected. Imo we just > >> >> need to add a flag to execbuf so that userspace can tell the kernel to > >> >> create a fence for that execbuf, and switch one of the leftover rsvd > >> >> fields to __s32 as an outparam for the fd. > >> > > >> > Given that I've got a new execbuf coming too, I just wanted to keep > >> > them separate. Any compelling reason to try to wedge it into execbuf? > >> > >> The new execbuf is for svm, and there we obviously need fences. But we > >> also need proper fence support everywhere else (hence also the comment > >> that we need support for fences in drm events). > >> > >> >> Then we need similar flags for vblank events and pageflips to do the > >> >> same (obviously those are drm core patches) and it's all there. That > >> >> should probably integrated as a special type of drm_event, so that > >> >> drivers don't need to change a single line of code. > >> > > >> > Except for actually using the fences... > >> > >> Actually no, nothing needed - drivers already signal drm_events in all > >> the right places, so we really only need to change > >> drm_send_vblank_event. And ofc we need to rework the code in the > >> pageflip/atomic/vblank_wait ioctl code in the drm core to create a > >> fence (and return it to userspace) instead of a normal drm event. > > > > Actually yes. You get back a fence object and want to do something > > with it, right? That means new code. Plus modifying current execbuf > > users that want fences to pass in a flag. > > This comment was specifically about vblank and pageflips, _not_ about > execbuf. At least that's been what I've thought while writing the > original mail and reading your reply. Looks like we have a > misunderstanding here. Since for vblank and pageflip we really can do > it all in the drm core. I was thinking of userspace drivers and userspace, not kernel internals... that's the disconnect. _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx
