On Mon, 26 Nov 2007, Heikki Lindholm wrote: > I had a look at the proposal and the thread at > http://thread.gmane.org/gmane.linux.alsa.devel/45237/focus=45573 My initial implementation following proposal is bellow for review and comments. I also changed timestamps for ALSA timers to use monotonic clocks (can be switched back using a module parameter). Jaroslav diff -r 5e8cab953031 core/pcm_lib.c --- a/core/pcm_lib.c Mon Nov 26 09:00:56 2007 +0100 +++ b/core/pcm_lib.c Mon Nov 26 14:50:01 2007 +0100 @@ -188,7 +188,7 @@ static inline int snd_pcm_update_hw_ptr_ snd_pcm_sframes_t delta; if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_MMAP) - getnstimeofday((struct timespec *)&runtime->status->tstamp); + snd_pcm_gettime(runtime, (struct timespec *)&runtime->status->tstamp); pos = snd_pcm_update_hw_ptr_pos(substream, runtime); if (pos == SNDRV_PCM_POS_XRUN) { xrun(substream); diff -r 5e8cab953031 core/pcm_native.c --- a/core/pcm_native.c Mon Nov 26 09:00:56 2007 +0100 +++ b/core/pcm_native.c Mon Nov 26 15:19:22 2007 +0100 @@ -598,9 +598,9 @@ int snd_pcm_status(struct snd_pcm_substr if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_MMAP) status->tstamp = runtime->status->tstamp; else - getnstimeofday(&status->tstamp); + snd_pcm_gettime(runtime, &status->tstamp); } else - getnstimeofday(&status->tstamp); + snd_pcm_gettime(runtime, &status->tstamp); status->appl_ptr = runtime->control->appl_ptr; status->hw_ptr = runtime->status->hw_ptr; if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) { @@ -688,7 +688,7 @@ static void snd_pcm_trigger_tstamp(struc if (runtime->trigger_master == NULL) return; if (runtime->trigger_master == substream) { - getnstimeofday(&runtime->trigger_tstamp); + snd_pcm_gettime(runtime, &runtime->trigger_tstamp); } else { snd_pcm_trigger_tstamp(runtime->trigger_master); runtime->trigger_tstamp = runtime->trigger_master->runtime->trigger_tstamp; @@ -2519,6 +2519,21 @@ static int snd_pcm_sync_ptr(struct snd_p return -EFAULT; return 0; } + +static int snd_pcm_tstamp(struct snd_pcm_substream *substream, int __user *_arg) +{ + struct snd_pcm_runtime *runtime = substream->runtime; + int arg; + + if (get_user(arg, _arg)) + return -EFAULT; + if (arg < 0 || arg > SNDRV_PCM_TSTAMP_TYPE_LAST) + return -EINVAL; + runtime->tstamp_type = SNDRV_PCM_TSTAMP_TYPE_GETTIMEOFDAY; + if (arg == SNDRV_PCM_TSTAMP_TYPE_MONOTONIC) + runtime->tstamp_type = SNDRV_PCM_TSTAMP_TYPE_MONOTONIC; + return 0; +} static int snd_pcm_common_ioctl1(struct file *file, struct snd_pcm_substream *substream, @@ -2531,8 +2546,8 @@ static int snd_pcm_common_ioctl1(struct return put_user(SNDRV_PCM_VERSION, (int __user *)arg) ? -EFAULT : 0; case SNDRV_PCM_IOCTL_INFO: return snd_pcm_info_user(substream, arg); - case SNDRV_PCM_IOCTL_TSTAMP: /* just for compatibility */ - return 0; + case SNDRV_PCM_IOCTL_TSTAMP: + return snd_pcm_tstamp(substream, arg); case SNDRV_PCM_IOCTL_HW_REFINE: return snd_pcm_hw_refine_user(substream, arg); case SNDRV_PCM_IOCTL_HW_PARAMS: diff -r 5e8cab953031 core/timer.c --- a/core/timer.c Mon Nov 26 09:00:56 2007 +0100 +++ b/core/timer.c Mon Nov 26 14:59:33 2007 +0100 @@ -44,11 +44,14 @@ #endif static int timer_limit = DEFAULT_TIMER_LIMIT; +static int timer_tstamp_monotonic = 1; MODULE_AUTHOR("Jaroslav Kysela <perex@xxxxxxxx>, Takashi Iwai <tiwai@xxxxxxx>"); MODULE_DESCRIPTION("ALSA timer interface"); MODULE_LICENSE("GPL"); module_param(timer_limit, int, 0444); MODULE_PARM_DESC(timer_limit, "Maximum global timers in system."); +module_param(timer_tstamp_monotonic, int, 0444); +MODULE_PARM_DESC(timer_tstamp_monotonic, "Use posix monotonic clock source for timestamps (default)."); struct snd_timer_user { struct snd_timer_instance *timeri; @@ -381,7 +384,10 @@ static void snd_timer_notify1(struct snd struct snd_timer_instance *ts; struct timespec tstamp; - getnstimeofday(&tstamp); + if (timer_tstamp_monotonic) + do_posix_clock_monotonic_gettime(&tstamp); + else + getnstimeofday(&tstamp); snd_assert(event >= SNDRV_TIMER_EVENT_START && event <= SNDRV_TIMER_EVENT_PAUSE, return); if (event == SNDRV_TIMER_EVENT_START || @@ -1182,8 +1188,12 @@ static void snd_timer_user_tinterrupt(st spin_unlock(&tu->qlock); return; } - if (tu->last_resolution != resolution || ticks > 0) - getnstimeofday(&tstamp); + if (tu->last_resolution != resolution || ticks > 0) { + if (timer_tstamp_monotonic) + do_posix_clock_monotonic_gettime(&tstamp); + else + getnstimeofday(&tstamp); + } if ((tu->filter & (1 << SNDRV_TIMER_EVENT_RESOLUTION)) && tu->last_resolution != resolution) { r1.event = SNDRV_TIMER_EVENT_RESOLUTION; diff -r 5e8cab953031 include/asound.h --- a/include/asound.h Mon Nov 26 09:00:56 2007 +0100 +++ b/include/asound.h Mon Nov 26 15:02:57 2007 +0100 @@ -435,6 +435,13 @@ struct snd_xfern { }; enum { + SNDRV_PCM_TSTAMP_TYPE_GETTIMEOFDAY = 0, /* gettimeofday equivalent */ + SNDRV_PCM_TSTAMP_TYPE_GETTIMEOFDAY1, /* for compatibility, equal to zero */ + SNDRV_PCM_TSTAMP_TYPE_MONOTONIC, /* posix_clock_monotonic equivalent */ + SNDRV_PCM_TSTAMP_TYPE_LAST = SNDRV_PCM_TSTAMP_TYPE_MONOTONIC, +}; + +enum { SNDRV_PCM_IOCTL_PVERSION = _IOR('A', 0x00, int), SNDRV_PCM_IOCTL_INFO = _IOR('A', 0x01, struct snd_pcm_info), SNDRV_PCM_IOCTL_TSTAMP = _IOW('A', 0x02, int), diff -r 5e8cab953031 include/pcm.h --- a/include/pcm.h Mon Nov 26 09:00:56 2007 +0100 +++ b/include/pcm.h Mon Nov 26 15:20:22 2007 +0100 @@ -323,6 +323,7 @@ struct snd_pcm_runtime { /* -- timer -- */ unsigned int timer_resolution; /* timer resolution */ + int tstamp_type; /* timestamp type */ /* -- DMA -- */ unsigned char *dma_area; /* DMA area */ @@ -952,6 +953,15 @@ void snd_pcm_timer_init(struct snd_pcm_s void snd_pcm_timer_init(struct snd_pcm_substream *substream); void snd_pcm_timer_done(struct snd_pcm_substream *substream); +static inline void snd_pcm_gettime(struct snd_pcm_runtime *runtime, + struct timespec *tv) +{ + if (runtime->tstamp_type == SNDRV_PCM_TSTAMP_TYPE_MONOTONIC) + do_posix_clock_monotonic_gettime(tv); + else + getnstimeofday(tv); +} + /* * Memory */ ----- Jaroslav Kysela <perex@xxxxxxxx> Linux Kernel Sound Maintainer ALSA Project _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
