On Mon, Jun 22, 2015 at 02:22:54PM +0100, Chris Wilson wrote: > On Mon, Jun 22, 2015 at 03:25:07PM +0530, sourab.gupta@xxxxxxxxx wrote: > > From: Sourab Gupta <sourab.gupta@xxxxxxxxx> > > > > To collect timestamps around any GPU workload, we need to insert > > commands to capture them into the ringbuffer. Therefore, during the stop event > > call, we need to wait for GPU to complete processing the last request for > > which these commands were inserted. > > We need to ensure this processing is done before event_destroy callback which > > deallocates the buffer for holding the data. > > There's no reason for this to be synchronous. Just that you need an > active reference on the output buffer to be only released after the > final request. Yeah I think the interaction between OA sampling and GEM is the critical piece here for both patch series. Step one is to have a per-pmu lock to keep track of data private to OA and mmio based sampling as a starting point. Then we need to figure out how to structure the connection without OA/PMU and gem trampling over each another's feet. Wrt requests those are refcounted already and just waiting on them doesn't need dev->struct_mutex. That should be all you need, assuming you do correctly refcount them ... -Daniel -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx
