On Fri, Mar 20, 2015 at 04:00:50PM +0100, Daniel Vetter wrote: > On Fri, Mar 20, 2015 at 02:45:04PM +0000, Chris Wilson wrote: > > On Fri, Mar 20, 2015 at 03:32:52PM +0100, Daniel Vetter wrote: > > > But if we do that short-circuiting in ring_idle the all the requests > > > _should_ be completed. Which meanse retire_request_ring should move all > > > buffers to the inactive list, even when we do that before retiring > > > requests. > > > > We test for the requests to be retired after we test for the buffers to > > be retired. It is very easy then for us to have active buffers as the > > seqno advanced after the buffer retirement and before the requests. That > > is (one of) the reasons why we previously sampled seqno only once when > > retiring buffers + requests. > > Yeah I get that part of the race. But before we retire anything in these > callsites we call gpu_idle. And that waits for everything to complete, > except whent there are not outstanding requests (i.e. ->request_list is > empyt). So either > - ->request_list is empty in ring_idle, which means all requests should > have completed. Even if there are some lingering active buffers still > around we should clean them up. > - ->request_list is not empty, in which case we do a full wait for the > most recent request. Again all requests should have completed and we > should be able to clean out both request and active lists. > > I do see how we can get out of the retire_request functions with requests > empty but still active buffers around. But I don't understand how that's > possible with a gpu_idle in front. And thus far all traces are from places > where we do call gpu_idle first. > > Or am I missing something? The retire comes before the before the gpu_idle (we retire often as a part of busy, execbuffer, timers etc). The traces show exactly that. -Chris -- Chris Wilson, Intel Open Source Technology Centre _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx
