Re: [alsa-devel] [PATCH 2/2] ALSA: pcm: Allow aborting mutex lock at OSS read/write loops

On 01/08/2018 03:25 PM, Takashi Iwai wrote:

@@ -1438,8 +1441,11 @@ static ssize_t snd_pcm_oss_read1(struct snd_pcm_substream *substream, char __use

if ((tmp = snd_pcm_oss_make_ready(substream)) < 0) return tmp;

• mutex_lock(&runtime->oss.params_lock); while (bytes > 0) {

• if (mutex_lock_interruptible(&runtime->oss.params_lock)) {
  

• 	tmp = -EINTR;
  

For consistency ERESTARTSYS I guess? In the end this is the same as signal_pending().

• 	break;
  

• }
  

  if (bytes < runtime->oss.period_bytes || runtime->oss.buffer_used > 0) { if (runtime->oss.buffer_used == 0) { tmp = snd_pcm_oss_read2(substream, runtime->oss.buffer, runtime->oss.period_bytes, 1);

@@ -1470,16 +1476,16 @@ static ssize_t snd_pcm_oss_read1(struct snd_pcm_substream *substream, char __use bytes -= tmp; xfer += tmp; }

• err:

• mutex_unlock(&runtime->oss.params_lock);
  

• if (tmp < 0)
  

• 	break;
  

  if (signal_pending(current)) { tmp = -ERESTARTSYS;

• 	goto err;
  

• 	break;
  

  }

• tmp = 0;
  

  }

• mutex_unlock(&runtime->oss.params_lock);
• return xfer;
• err:
• mutex_unlock(&runtime->oss.params_lock); return xfer > 0 ? (snd_pcm_sframes_t)xfer : tmp;

}