On Fri, Jul 01, 2016 at 05:59:30PM +0300, Nandor Han wrote: > > > On 28/06/16 17:34, Vinod Koul wrote: > >On Thu, Jun 09, 2016 at 03:16:30PM +0300, Nandor Han wrote: > >>Having the SDMA driver use a tasklet for running the clients > >>callback introduce some issues: > >> - probability to have desynchronized data because of the > >> race condition created since the DMA transaction status > >> is retrieved only when the callback is executed, leaving > >> plenty of time for transaction status to get altered. > >> - inter-transfer latency which can leave channels idle. > >> > >>Move the callback execution, for cyclic channels, to SDMA > >>interrupt (as advised in `Documentation/dmaengine/provider.txt`) > >>to (a)reduce the inter-transfer latency and (b) eliminate the > >>race condition possibility where DMA transaction status might > >>be changed by the time is read. > >> > >>The responsibility of the SDMA interrupt latency > >>is moved to the SDMA clients which case by case should defer > >>the work to bottom-halves when needed. > > > >Both of these look fine. Please change the patch titles to dmaengine: xxxx > > > >Are these going to be merged thru dmaengine tree or serial one? > > > > I will send soon a V2 where I will fix the titles. If you are OK > with all the patchset it can be merged to dmaengine tree, otherwise > probably goes to serial one. Sure I can merge all.. provided ACKs on other patches. -- ~Vinod -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
