On 29.11.2017 15:25, Mikko Perttunen wrote: > On 29.11.2017 14:18, Dmitry Osipenko wrote: >> On 29.11.2017 12:10, Mikko Perttunen wrote: >>> On 12.11.2017 13:23, Dmitry Osipenko wrote: >>>> On 11.11.2017 00:15, Dmitry Osipenko wrote: >>>>> On 07.11.2017 18:29, Dmitry Osipenko wrote: >>>>>> On 07.11.2017 16:11, Mikko Perttunen wrote: >>>>>>> On 05.11.2017 19:14, Dmitry Osipenko wrote: >>>>>>>> On 05.11.2017 14:01, Mikko Perttunen wrote: >>>>>>>>> Add an option to host1x_channel_request to interruptibly wait for a >>>>>>>>> free channel. This allows IOCTLs that acquire a channel to block >>>>>>>>> the userspace. >>>>>>>>> >>>>>>>> >>>>>>>> Wouldn't it be more optimal to request channel and block after job's >>>>>>>> pining, >>>>>>>> when all patching and checks are completed? Note that right now we have >>>>>>>> locking >>>>>>>> around submission in DRM, which I suppose should go away by making locking >>>>>>>> fine >>>>>>>> grained. >>>>>>> >>>>>>> That would be possible, but I don't think it should matter much since >>>>>>> contention >>>>>>> here should not be the common case. >>>>>>> >>>>>>>> >>>>>>>> Or maybe it would be more optimal to just iterate over channels, like I >>>>>>>> suggested before [0]? >>>>>>> >>>>>>> Somehow I hadn't noticed this before, but this would break the invariant of >>>>>>> having one client/class per channel. >>>>>>> >>>>>> >>>>>> Yes, currently there is a weak relation of channel and clients device, but >>>>>> seems >>>>>> channels device is only used for printing dev_* messages and device could be >>>>>> borrowed from the channels job. I don't see any real point of hardwiring >>>>>> channel >>>>>> to a specific device or client. >>>>> >>>>> Although, it won't work with syncpoint assignment to channel. >>>> >>>> On the other hand.. it should work if one syncpoint could be assigned to >>>> multiple channels, couldn't it? >>> >>> A syncpoint can only be mapped to a single channel, so unfortunately this won't >>> work. >> Okay, in DRM we are requesting syncpoint on channels 'open' and syncpoint >> assignment happens on jobs submission. So firstly submitted job will assign >> syncpoint to the first channel and second job would re-assign syncpoint to a >> second channel while first job is still in-progress, how is it going to work? >> > > When a context is created, it's assigned both a syncpoint and channel and this > pair stays for as long as the context is alive (i.e. as long as there are jobs), > so even if the syncpoint is reassigned to a channel at every submit, it is > always assigned to the same channel, so nothing breaks. Multiple contexts cannot > share syncpoints so things work out. > > Obviously this is not ideal as we currently never unassign syncpoints but at > least it is not broken. Right, I forgot that you made tegra_drm_context_get_channel() to re-use requested channel if there are pending jobs. _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
