Messages in this thread | | | Date | Fri, 18 Mar 2011 00:12:58 +0100 | From | Knut Petersen <> | Subject | Re: [BUG][2.6.38] IRQ Lock Inversion / i915 fails |
| |
Thanks a lot. That patch below does indeed solve the irq lock inversion problem.
cu, Knut
> > The trigger callback should be called always in irq-disabled context, > so this should be OK. But loopback_pos_update() is called in the > timer callback, and this can be the issue. > > Knut, how about the patch below? > > > thanks, > > Takashi > > --- > diff --git a/sound/drivers/aloop.c b/sound/drivers/aloop.c > index 12b44b0..a0da775 100644 > --- a/sound/drivers/aloop.c > +++ b/sound/drivers/aloop.c > @@ -482,8 +482,9 @@ static unsigned int loopback_pos_update(struct loopback_cable *cable) > cable->streams[SNDRV_PCM_STREAM_CAPTURE]; > unsigned long delta_play = 0, delta_capt = 0; > unsigned int running; > + unsigned long flags; > > - spin_lock(&cable->lock); > + spin_lock_irqsave(&cable->lock, flags); > running = cable->running ^ cable->pause; > if (running & (1 << SNDRV_PCM_STREAM_PLAYBACK)) { > delta_play = jiffies - dpcm_play->last_jiffies; > @@ -495,10 +496,8 @@ static unsigned int loopback_pos_update(struct loopback_cable *cable) > dpcm_capt->last_jiffies += delta_capt; > } > > - if (delta_play == 0 && delta_capt == 0) { > - spin_unlock(&cable->lock); > - return running; > - } > + if (delta_play == 0 && delta_capt == 0) > + goto unlock; > > if (delta_play > delta_capt) { > loopback_bytepos_update(dpcm_play, delta_play - delta_capt, > @@ -510,14 +509,14 @@ static unsigned int loopback_pos_update(struct loopback_cable *cable) > delta_capt = delta_play; > } > > - if (delta_play == 0 && delta_capt == 0) { > - spin_unlock(&cable->lock); > - return running; > - } > + if (delta_play == 0 && delta_capt == 0) > + goto unlock; > + > /* note delta_capt == delta_play at this moment */ > loopback_bytepos_update(dpcm_capt, delta_capt, BYTEPOS_UPDATE_COPY); > loopback_bytepos_update(dpcm_play, delta_play, BYTEPOS_UPDATE_POSONLY); > - spin_unlock(&cable->lock); > + unlock: > + spin_unlock_irqrestore(&cable->lock, flags); > return running; > } > >
| |