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Merge branch 'fix/pcm-hwptr' into for-linus 

* fix/pcm-hwptr:
  ALSA: pcm - Fix hwptr buffer-size overlap bug
  ALSA: pcm - Fix warnings in debug loggings
  ALSA: pcm - Add logging of hwptr updates and interrupt updates
  ALSA: pcm - Fix regressions with VMware
This commit is contained in:
Takashi Iwai 2009-07-26 11:07:07 +02:00
parent de5d674c02 947ca210f1
commit b88158846f
2 changed files with 40 additions and 1 deletions
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5
Documentation/sound/alsa/Procfile.txt
View File

@ -101,6 +101,8 @@ card*/pcm*/xrun_debug
bit 0 = Enable XRUN/jiffies debug messages
bit 1 = Show stack trace at XRUN / jiffies check
bit 2 = Enable additional jiffies check
bit 3 = Log hwptr update at each period interrupt
bit 4 = Log hwptr update at each snd_pcm_update_hw_ptr()
When the bit 0 is set, the driver will show the messages to
kernel log when an xrun is detected. The debug message is
@ -117,6 +119,9 @@ card*/pcm*/xrun_debug
buggy) hardware that doesn't give smooth pointer updates.
This feature is enabled via the bit 2.
Bits 3 and 4 are for logging the hwptr records. Note that
these will give flood of kernel messages.
card*/pcm*/sub*/info
The general information of this PCM sub-stream.

36
sound/core/pcm_lib.c
View File

@ -233,6 +233,18 @@ static int snd_pcm_update_hw_ptr_interrupt(struct snd_pcm_substream *substream)
xrun(substream);
return -EPIPE;
}
if (xrun_debug(substream, 8)) {
char name[16];
pcm_debug_name(substream, name, sizeof(name));
snd_printd("period_update: %s: pos=0x%x/0x%x/0x%x, "
"hwptr=0x%lx, hw_base=0x%lx, hw_intr=0x%lx\n",
name, (unsigned int)pos,
(unsigned int)runtime->period_size,
(unsigned int)runtime->buffer_size,
(unsigned long)old_hw_ptr,
(unsigned long)runtime->hw_ptr_base,
(unsigned long)runtime->hw_ptr_interrupt);
}
hw_base = runtime->hw_ptr_base;
new_hw_ptr = hw_base + pos;
hw_ptr_interrupt = runtime->hw_ptr_interrupt + runtime->period_size;
@ -244,18 +256,27 @@ static int snd_pcm_update_hw_ptr_interrupt(struct snd_pcm_substream *substream)
delta = new_hw_ptr - hw_ptr_interrupt;
}
if (delta < 0) {
delta += runtime->buffer_size;
if (runtime->periods == 1 || new_hw_ptr < old_hw_ptr)
delta += runtime->buffer_size;
if (delta < 0) {
hw_ptr_error(substream,
"Unexpected hw_pointer value "
"(stream=%i, pos=%ld, intr_ptr=%ld)\n",
substream->stream, (long)pos,
(long)hw_ptr_interrupt);
#if 1
/* simply skipping the hwptr update seems more
* robust in some cases, e.g. on VMware with
* inaccurate timer source
*/
return 0; /* skip this update */
#else
/* rebase to interrupt position */
hw_base = new_hw_ptr = hw_ptr_interrupt;
/* align hw_base to buffer_size */
hw_base -= hw_base % runtime->buffer_size;
delta = 0;
#endif
} else {
hw_base += runtime->buffer_size;
if (hw_base >= runtime->boundary)
@ -344,6 +365,19 @@ int snd_pcm_update_hw_ptr(struct snd_pcm_substream *substream)
xrun(substream);
return -EPIPE;
}
if (xrun_debug(substream, 16)) {
char name[16];
pcm_debug_name(substream, name, sizeof(name));
snd_printd("hw_update: %s: pos=0x%x/0x%x/0x%x, "
"hwptr=0x%lx, hw_base=0x%lx, hw_intr=0x%lx\n",
name, (unsigned int)pos,
(unsigned int)runtime->period_size,
(unsigned int)runtime->buffer_size,
(unsigned long)old_hw_ptr,
(unsigned long)runtime->hw_ptr_base,
(unsigned long)runtime->hw_ptr_interrupt);
}
hw_base = runtime->hw_ptr_base;
new_hw_ptr = hw_base + pos;