Messages in this thread |  | | Date | Thu, 31 Aug 2017 16:26:50 +0200 | From | Takashi Iwai <> | Subject | Re: [PATCH 23/25] ALSA/dummy: Replace tasklet with softirq hrtimer |
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On Thu, 31 Aug 2017 16:21:17 +0200, Takashi Sakamoto wrote: > > Hi, > > On Aug 31 2017 21:23, Anna-Maria Gleixner wrote: > > From: Thomas Gleixner <tglx@linutronix.de> > > > > The tasklet is used to defer the execution of snd_pcm_period_elapsed() to > > the softirq context. Using the CLOCK_MONOTONIC_SOFT base invokes the timer > > callback in softirq context as well which renders the tasklet useless. > > > > Signed-off-by: Thomas Gleixner <tglx@linutronix.de> > > Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de> > > Cc: Jaroslav Kysela <perex@perex.cz> > > Cc: Takashi Iwai <tiwai@suse.com> > > Cc: Takashi Sakamoto <o-takashi@sakamocchi.jp> > > Cc: alsa-devel@alsa-project.org > > --- > > sound/drivers/dummy.c | 16 +++------------- > > 1 file changed, 3 insertions(+), 13 deletions(-) > > I prefer this patch as long as this driver can still receive callbacks > from hrtimer subsystem. > > Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> > > Unfortunately, I have too poor machine to compile whole kernel now, thus > didn't do any tests, sorry. > > I note that ALSA pcsp driver uses a combination of hrtimer/tasklet for the > same purpose. I think we can simplify it, too. Please refer to a patch in > the end of this message. (But not tested yet for the above reason...)
The pcsp is a bit special. It's really high frequent irq calls for controlling the beep on/off, thus offloading the whole isn't good.
thanks,
Takashi
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