On Fri, Jul 13, 2012 at 12:35 PM, Tom Cooksey <tom.cooksey@xxxxxxx> wrote: > My other thought is around atomicity. Could this be extended to > (safely) allow for hardware devices which might want to access > multiple buffers simultaneously? I think it probably can with > some tweaks to the interface? An atomic function which does > something like "give me all the fences for all these buffers > and add this fence to each instead/as-well-as"? fwiw, what I'm leaning towards right now is combining dma-fence w/ Maarten's idea of dma-buf-mgr (not sure if you saw his patches?). And let dmabufmgr handle the multi-buffer reservation stuff. And possibly the read vs write access, although this I'm not 100% sure on... the other option being the concept of read vs write (or exclusive/non-exclusive) fences. In the current state, the fence is quite simple, and doesn't care *what* it is fencing, which seems advantageous when you get into trying to deal with combinations of devices sharing buffers, some of whom can do hw sync, and some who can't. So having a bit of partitioning from the code dealing w/ sequencing who can access the buffers when and for what purpose seems like it might not be a bad idea. Although I'm still working through the different alternatives. BR, -R -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
