> -----Original Message----- > From: Francisco Jerez [mailto:curroje...@riseup.net] > Sent: Monday, April 14, 2014 11:21 AM > To: Dorrington, Albert; mesa-dev@lists.freedesktop.org > Subject: EXTERNAL: Re: [Mesa-dev] Clover clEnqueue* function don't > implement blocking? > > "Dorrington, Albert" <albert.dorring...@lmco.com> writes: > > > From reviewing api/transfer.cpp, it looks like all of the API calls that > > have a > blocking parameter do not have anything that implement blocking > functionality. > > > > clEnqueueReadBuffer(), clEnqueueWriteBuffer(), > > clEnqueueReadBufferRect(), clEnqueueWriteBufferRect(), > > clEnqueueReadImage(), clEnqueueWriteImage() clEnqueueMapBuffer(), > > clEnqueueMapImage() > > > > For all of these functions, shouldn't there be a conditional wait on the > event implemented, something like the following? > > > > auto hev = create<hard_event>(...); > > ret_object(rd_ev, hev); > > if (blocking) { hev().wait(); } > > return CL_SUCCESS; > > > > My initial tests indicate this works, but I'm not sure if I'm missing > > something > in the event handling/cleanup. > > > > Nope, that's usually not necessary. The "blocking" parameter of some > OpenCL entry points surprisingly doesn't imply that the enqueued operation > itself should be blocking, it just determines whether the application is > allowed to reuse the provided memory for other purposes after the call > returns -- and in our implementation that's always the case because we don't > do DMA from client addresses, as we discussed previously, so we can ignore > the blocking parameter most of the time. > > Note that this doesn't mean that buffer upload is necessarily synchronous > [buffer download is, though], pipe drivers are free to keep the written bits > in > some temporary storage and perform the final copy asynchronously. >
Ah, ok - that makes sense - I was misinterpreting the OpenCL spec. But when these events are queued, if there isn't a wait(), then what triggers their flush from the queued_events list? That seems to only happen when the hard_event::wait() is called (assuming the status is queued) Shouldn't something be flushing the queue as the events are processed (especially if nothing is pending on the events), well before the clFinish() call? _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev
