On Fri, 09 Jun 2017 09:01:56 +0200, Takashi Sakamoto wrote: > > On Jun 9 2017 15:53, Takashi Iwai wrote: > >>> From: Takashi Iwai <tiwai@xxxxxxx> > >>> Subject: [PATCH] ALSA: pcm: Suppress status/control mmap when ack ops is > >>> present > >>> > >>> The drivers using PCM ack ops require the notification whenever > >>> appl_ptr is updated in general. But when the PCM status/control page > >>> is mmapped, this notification doesn't happen, per design, thus it's > >>> not guaranteed to receive the fine-grained updates. > >>> > >>> For improving the situation, this patch simply suppresses the PCM > >>> status/control mmap when ack ops is defined. At least, for all > >>> existing drivers with ack, this should give more benefit. > >>> > >>> Once when we really need the full optimization with status/control > >>> mmap even using ack ops, we may reconsider the check, e.g. introducing > >>> a new flag. But, so far, this should be good enough. > >> > >> Yes this makes sense and we tested it for us, looks good > >> > >> Reveiwed-by: Vinod Koul <vinod.koul@xxxxxxxxx> > >> Tested-by: Subhransu S. Prusty <subhransu.s.prusty@xxxxxxxxx> > > > > OK, thanks. > > > > If Sakamato-san is happy with this change, I'm going to merge it for > > 4.13. > > I'm writing a long long message about my concern for this patch. Better to shorten, if you want to convince someone :) > I'm > happy if you postpone application to your for-next branch, till next > week. OK. Takashi _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
