ALSA: Rewrite hw_ptr updaters
Clean up and improve snd_pcm_update_hw_ptr*() functions.
snd_pcm_update_hw_ptr() tries to detect the unexpected hwptr jumps
more strictly to avoid the position mess-up, which often results in
the bad quality I/O with pulseaudio.
The hw-ptr skip error messages are printed when xrun proc is set to
non-zero.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/core/pcm_lib.c b/sound/core/pcm_lib.c
index 9216910..86ac9ae 100644
--- a/sound/core/pcm_lib.c
+++ b/sound/core/pcm_lib.c
@@ -125,19 +125,27 @@
}
}
+#ifdef CONFIG_SND_PCM_XRUN_DEBUG
+#define xrun_debug(substream) ((substream)->pstr->xrun_debug)
+#else
+#define xrun_debug(substream) 0
+#endif
+
+#define dump_stack_on_xrun(substream) do { \
+ if (xrun_debug(substream) > 1) \
+ dump_stack(); \
+ } while (0)
+
static void xrun(struct snd_pcm_substream *substream)
{
snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
-#ifdef CONFIG_SND_PCM_XRUN_DEBUG
- if (substream->pstr->xrun_debug) {
+ if (xrun_debug(substream)) {
snd_printd(KERN_DEBUG "XRUN: pcmC%dD%d%c\n",
substream->pcm->card->number,
substream->pcm->device,
substream->stream ? 'c' : 'p');
- if (substream->pstr->xrun_debug > 1)
- dump_stack();
+ dump_stack_on_xrun(substream);
}
-#endif
}
static inline snd_pcm_uframes_t snd_pcm_update_hw_ptr_pos(struct snd_pcm_substream *substream,
@@ -182,11 +190,21 @@
return 0;
}
+#define hw_ptr_error(substream, fmt, args...) \
+ do { \
+ if (xrun_debug(substream)) { \
+ if (printk_ratelimit()) { \
+ snd_printd("hda_codec: " fmt, ##args); \
+ } \
+ dump_stack_on_xrun(substream); \
+ } \
+ } while (0)
+
static inline int snd_pcm_update_hw_ptr_interrupt(struct snd_pcm_substream *substream)
{
struct snd_pcm_runtime *runtime = substream->runtime;
snd_pcm_uframes_t pos;
- snd_pcm_uframes_t new_hw_ptr, hw_ptr_interrupt;
+ snd_pcm_uframes_t new_hw_ptr, hw_ptr_interrupt, hw_base;
snd_pcm_sframes_t delta;
pos = snd_pcm_update_hw_ptr_pos(substream, runtime);
@@ -194,36 +212,47 @@
xrun(substream);
return -EPIPE;
}
- if (runtime->period_size == runtime->buffer_size)
- goto __next_buf;
- new_hw_ptr = runtime->hw_ptr_base + pos;
+ hw_base = runtime->hw_ptr_base;
+ new_hw_ptr = hw_base + pos;
hw_ptr_interrupt = runtime->hw_ptr_interrupt + runtime->period_size;
-
- delta = hw_ptr_interrupt - new_hw_ptr;
- if (delta > 0) {
- if ((snd_pcm_uframes_t)delta < runtime->buffer_size / 2) {
-#ifdef CONFIG_SND_PCM_XRUN_DEBUG
- if (runtime->periods > 1 && substream->pstr->xrun_debug) {
- snd_printd(KERN_ERR "Unexpected hw_pointer value [1] (stream = %i, delta: -%ld, max jitter = %ld): wrong interrupt acknowledge?\n", substream->stream, (long) delta, runtime->buffer_size / 2);
- if (substream->pstr->xrun_debug > 1)
- dump_stack();
- }
-#endif
- return 0;
+ delta = new_hw_ptr - hw_ptr_interrupt;
+ if (hw_ptr_interrupt == runtime->boundary)
+ hw_ptr_interrupt = 0;
+ if (delta < 0) {
+ 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);
+ /* rebase to interrupt position */
+ hw_base = new_hw_ptr = hw_ptr_interrupt;
+ delta = 0;
+ } else {
+ hw_base += runtime->buffer_size;
+ if (hw_base == runtime->boundary)
+ hw_base = 0;
+ new_hw_ptr = hw_base + pos;
}
- __next_buf:
- runtime->hw_ptr_base += runtime->buffer_size;
- if (runtime->hw_ptr_base == runtime->boundary)
- runtime->hw_ptr_base = 0;
- new_hw_ptr = runtime->hw_ptr_base + pos;
}
-
+ if (delta > runtime->period_size) {
+ hw_ptr_error(substream,
+ "Lost interrupts? "
+ "(stream=%i, delta=%ld, intr_ptr=%ld)\n",
+ substream->stream, (long)delta,
+ (long)hw_ptr_interrupt);
+ /* rebase hw_ptr_interrupt */
+ hw_ptr_interrupt =
+ new_hw_ptr - new_hw_ptr % runtime->period_size;
+ }
if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
runtime->silence_size > 0)
snd_pcm_playback_silence(substream, new_hw_ptr);
+ runtime->hw_ptr_base = hw_base;
runtime->status->hw_ptr = new_hw_ptr;
- runtime->hw_ptr_interrupt = new_hw_ptr - new_hw_ptr % runtime->period_size;
+ runtime->hw_ptr_interrupt = hw_ptr_interrupt;
return snd_pcm_update_hw_ptr_post(substream, runtime);
}
@@ -233,7 +262,7 @@
{
struct snd_pcm_runtime *runtime = substream->runtime;
snd_pcm_uframes_t pos;
- snd_pcm_uframes_t old_hw_ptr, new_hw_ptr;
+ snd_pcm_uframes_t old_hw_ptr, new_hw_ptr, hw_base;
snd_pcm_sframes_t delta;
old_hw_ptr = runtime->status->hw_ptr;
@@ -242,29 +271,38 @@
xrun(substream);
return -EPIPE;
}
- new_hw_ptr = runtime->hw_ptr_base + pos;
+ hw_base = runtime->hw_ptr_base;
+ new_hw_ptr = hw_base + pos;
- delta = old_hw_ptr - new_hw_ptr;
- if (delta > 0) {
- if ((snd_pcm_uframes_t)delta < runtime->buffer_size / 2) {
-#ifdef CONFIG_SND_PCM_XRUN_DEBUG
- if (runtime->periods > 2 && substream->pstr->xrun_debug) {
- snd_printd(KERN_ERR "Unexpected hw_pointer value [2] (stream = %i, delta: -%ld, max jitter = %ld): wrong interrupt acknowledge?\n", substream->stream, (long) delta, runtime->buffer_size / 2);
- if (substream->pstr->xrun_debug > 1)
- dump_stack();
- }
-#endif
+ delta = new_hw_ptr - old_hw_ptr;
+ if (delta < 0) {
+ delta += runtime->buffer_size;
+ if (delta < 0) {
+ hw_ptr_error(substream,
+ "Unexpected hw_pointer value [2] "
+ "(stream=%i, pos=%ld, old_ptr=%ld)\n",
+ substream->stream, (long)pos,
+ (long)old_hw_ptr);
return 0;
}
- runtime->hw_ptr_base += runtime->buffer_size;
- if (runtime->hw_ptr_base == runtime->boundary)
- runtime->hw_ptr_base = 0;
- new_hw_ptr = runtime->hw_ptr_base + pos;
+ hw_base += runtime->buffer_size;
+ if (hw_base == runtime->boundary)
+ hw_base = 0;
+ new_hw_ptr = hw_base + pos;
+ }
+ if (delta > runtime->period_size && runtime->periods > 1) {
+ hw_ptr_error(substream,
+ "hw_ptr skipping! "
+ "(pos=%ld, delta=%ld, period=%ld)\n",
+ (long)pos, (long)delta,
+ (long)runtime->period_size);
+ return 0;
}
if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
runtime->silence_size > 0)
snd_pcm_playback_silence(substream, new_hw_ptr);
+ runtime->hw_ptr_base = hw_base;
runtime->status->hw_ptr = new_hw_ptr;
return snd_pcm_update_hw_ptr_post(substream, runtime);