On Fri, 30 Dec 2016 07:26:15 +0100,
sutar.mounesh@xxxxxxxxx wrote:
>
> From: Joshua Frkuska joshua_frkuska@xxxxxxxxxx
>
> This patch allows the effective period size to be a multiple of the slave-pcm period size.
> Allowing only exact multiple of original period size is achieved by borrowing code from the
> kernel hwrules implemention.
>
> This patch is intended to save cpu workload when for example, the slave operates with very
> small periods but a user does not need that small periods.
>
> This feature is enabled by default and can be disabled by adding config option 'var_periodsize 0'.
>
> Signed-off-by: Alexander Jahn <ajahn@xxxxxxxxxxxxxx>
> Signed-off-by: Andreas Pape <apape@xxxxxxxxxxxxxx>
Looks like a good improvement. I applied this patch with a slight
coding style fixes.
thanks,
Takashi
> diff --git a/src/pcm/pcm_direct.c b/src/pcm/pcm_direct.c
> index 6434983..8f42b19 100644
> --- a/src/pcm/pcm_direct.c
> +++ b/src/pcm/pcm_direct.c
> @@ -660,6 +660,28 @@ static int hw_param_interval_refine_minmax(snd_pcm_hw_params_t *params,
> return hw_param_interval_refine_one(params, var, &t);
> }
>
> +/* this code is used 'as-is' from the alsa kernel code */
> +static int snd_interval_step(struct snd_interval *i, unsigned int min, unsigned int step)
> +{
> + unsigned int n;
> + int changed = 0;
> + n = (i->min - min) % step;
> + if (n != 0 || i->openmin) {
> + i->min += step - n;
> + changed = 1;
> + }
> + n = (i->max - min) % step;
> + if (n != 0 || i->openmax) {
> + i->max -= n;
> + changed = 1;
> + }
> + if (snd_interval_checkempty(i)) {
> + i->empty = 1;
> + return -EINVAL;
> + }
> + return changed;
> +}
> +
> #undef REFINE_DEBUG
>
> int snd_pcm_direct_hw_refine(snd_pcm_t *pcm, snd_pcm_hw_params_t *params)
> @@ -710,15 +732,16 @@ int snd_pcm_direct_hw_refine(snd_pcm_t *pcm, snd_pcm_hw_params_t *params)
> &dshare->shmptr->hw.rate);
> if (err < 0)
> return err;
> - err = hw_param_interval_refine_one(params, SND_PCM_HW_PARAM_PERIOD_SIZE,
> - &dshare->shmptr->hw.period_size);
> - if (err < 0)
> - return err;
> - err = hw_param_interval_refine_one(params, SND_PCM_HW_PARAM_PERIOD_TIME,
> - &dshare->shmptr->hw.period_time);
> - if (err < 0)
> - return err;
> +
> if (dshare->max_periods < 0) {
> + err = hw_param_interval_refine_one(params, SND_PCM_HW_PARAM_PERIOD_SIZE,
> + &dshare->shmptr->hw.period_size);
> + if (err < 0)
> + return err;
> + err = hw_param_interval_refine_one(params, SND_PCM_HW_PARAM_PERIOD_TIME,
> + &dshare->shmptr->hw.period_time);
> + if (err < 0)
> + return err;
> err = hw_param_interval_refine_one(params, SND_PCM_HW_PARAM_BUFFER_SIZE,
> &dshare->shmptr->hw.buffer_size);
> if (err < 0)
> @@ -730,11 +753,38 @@ int snd_pcm_direct_hw_refine(snd_pcm_t *pcm, snd_pcm_hw_params_t *params)
> } else if (params->rmask & ((1<<SND_PCM_HW_PARAM_PERIODS)|
> (1<<SND_PCM_HW_PARAM_BUFFER_BYTES)|
> (1<<SND_PCM_HW_PARAM_BUFFER_SIZE)|
> - (1<<SND_PCM_HW_PARAM_BUFFER_TIME))) {
> + (1<<SND_PCM_HW_PARAM_BUFFER_TIME)|
> + (1<<SND_PCM_HW_PARAM_PERIOD_TIME)|
> + (1<<SND_PCM_HW_PARAM_PERIOD_SIZE)|
> + (1<<SND_PCM_HW_PARAM_PERIOD_BYTES))) {
> + snd_interval_t period_size = dshare->shmptr->hw.period_size;
> + snd_interval_t period_time = dshare->shmptr->hw.period_time;
> int changed;
> unsigned int max_periods = dshare->max_periods;
> if (max_periods < 2)
> max_periods = dshare->slave_buffer_size / dshare->slave_period_size;
> +
> + /*make sure buffer size does not exceed slave buffer size*/
> + err = hw_param_interval_refine_minmax(params, SND_PCM_HW_PARAM_BUFFER_SIZE,
> + 2 * dshare->slave_period_size, dshare->slave_buffer_size);
> + if (err < 0)
> + return err;
> + if (dshare->var_periodsize) {
> + /*more tolerant settings...*/
> + if((dshare->shmptr->hw.buffer_size.max / 2) > period_size.max)
> + period_size.max = dshare->shmptr->hw.buffer_size.max / 2;
> + if((dshare->shmptr->hw.buffer_time.max / 2) > period_time.max)
> + period_time.max = dshare->shmptr->hw.buffer_time.max / 2;
> + }
> +
> + err = hw_param_interval_refine_one(params, SND_PCM_HW_PARAM_PERIOD_SIZE,
> + &period_size);
> + if (err < 0)
> + return err;
> + err = hw_param_interval_refine_one(params, SND_PCM_HW_PARAM_PERIOD_TIME,
> + &period_time);
> + if (err < 0)
> + return err;
> do {
> changed = 0;
> err = hw_param_interval_refine_minmax(params, SND_PCM_HW_PARAM_PERIODS,
> @@ -746,8 +796,16 @@ int snd_pcm_direct_hw_refine(snd_pcm_t *pcm, snd_pcm_hw_params_t *params)
> if (err < 0)
> return err;
> changed |= err;
> + err = snd_interval_step(hw_param_interval(params, SND_PCM_HW_PARAM_PERIOD_SIZE),
> + 0, dshare->slave_period_size);
> + if (err < 0)
> + return err;
> + changed |= err;
> + if (err)
> + params->rmask |= (1<<SND_PCM_HW_PARAM_PERIOD_SIZE);
> } while (changed);
> }
> + dshare->timer_ticks = hw_param_interval(params, SND_PCM_HW_PARAM_PERIOD_SIZE)->max/dshare->slave_period_size;
> params->info = dshare->shmptr->s.info;
> #ifdef REFINE_DEBUG
> snd_output_puts(log, "DMIX REFINE (end):\n");
> @@ -1183,6 +1241,7 @@ int snd_pcm_direct_initialize_poll_fd(snd_pcm_direct_t *dmix)
>
> dmix->tread = 1;
> dmix->timer_need_poll = 0;
> + dmix->timer_ticks = 1;
> ret = snd_pcm_info(dmix->spcm, &info);
> if (ret < 0) {
> SNDERR("unable to info for slave pcm");
> @@ -1366,7 +1425,7 @@ int snd_pcm_direct_set_timer_params(snd_pcm_direct_t *dmix)
> snd_timer_params_set_auto_start(¶ms, 1);
> if (dmix->type != SND_PCM_TYPE_DSNOOP)
> snd_timer_params_set_early_event(¶ms, 1);
> - snd_timer_params_set_ticks(¶ms, 1);
> + snd_timer_params_set_ticks(¶ms, dmix->timer_ticks);
> if (dmix->tread) {
> filter = (1<<SND_TIMER_EVENT_TICK) |
> dmix->timer_events;
> @@ -1656,6 +1715,7 @@ int snd_pcm_direct_parse_open_conf(snd_config_t *root, snd_config_t *conf,
> rec->ipc_gid = -1;
> rec->slowptr = 1;
> rec->max_periods = 0;
> + rec->var_periodsize = 1;
>
> /* read defaults */
> if (snd_config_search(root, "defaults.pcm.dmix_max_periods", &n) >= 0) {
> @@ -1762,6 +1822,13 @@ int snd_pcm_direct_parse_open_conf(snd_config_t *root, snd_config_t *conf,
> rec->max_periods = val;
> continue;
> }
> + if (strcmp(id, "var_periodsize") == 0) {
> + err = snd_config_get_bool(n);
> + if (err < 0)
> + return err;
> + rec->var_periodsize = err;
> + continue;
> + }
> SNDERR("Unknown field %s", id);
> return -EINVAL;
> }
> diff --git a/src/pcm/pcm_direct.h b/src/pcm/pcm_direct.h
> index 611ad29..91e816c 100644
> --- a/src/pcm/pcm_direct.h
> +++ b/src/pcm/pcm_direct.h
> @@ -147,12 +147,14 @@ struct snd_pcm_direct {
> int tread: 1;
> int timer_need_poll: 1;
> unsigned int timer_events;
> + unsigned int timer_ticks;
> int server_fd;
> pid_t server_pid;
> snd_timer_t *timer; /* timer used as poll_fd */
> int interleaved; /* we have interleaved buffer */
> int slowptr; /* use slow but more precise ptr updates */
> int max_periods; /* max periods (-1 = fixed periods, 0 = max buffer size) */
> + int var_periodsize; /* allow variable period size if max_periods is != -1*/
> unsigned int channels; /* client's channels */
> unsigned int *bindings;
> union {
> @@ -326,6 +328,7 @@ struct snd_pcm_direct_open_conf {
> int ipc_gid;
> int slowptr;
> int max_periods;
> + int var_periodsize;
> snd_config_t *slave;
> snd_config_t *bindings;
> };
> diff --git a/src/pcm/pcm_dmix.c b/src/pcm/pcm_dmix.c
> index 825677f..0ab7323 100644
> --- a/src/pcm/pcm_dmix.c
> +++ b/src/pcm/pcm_dmix.c
> @@ -1040,6 +1040,7 @@ int snd_pcm_dmix_open(snd_pcm_t **pcmp, const char *name,
> dmix->state = SND_PCM_STATE_OPEN;
> dmix->slowptr = opts->slowptr;
> dmix->max_periods = opts->max_periods;
> + dmix->var_periodsize = opts->var_periodsize;
> dmix->sync_ptr = snd_pcm_dmix_sync_ptr;
>
> retry:
> diff --git a/src/pcm/pcm_dshare.c b/src/pcm/pcm_dshare.c
> index 29cd6c6..a1fed5d 100644
> --- a/src/pcm/pcm_dshare.c
> +++ b/src/pcm/pcm_dshare.c
> @@ -725,6 +725,7 @@ int snd_pcm_dshare_open(snd_pcm_t **pcmp, const char *name,
> dshare->state = SND_PCM_STATE_OPEN;
> dshare->slowptr = opts->slowptr;
> dshare->max_periods = opts->max_periods;
> + dshare->var_periodsize = opts->var_periodsize;
> dshare->sync_ptr = snd_pcm_dshare_sync_ptr;
>
> retry:
> diff --git a/src/pcm/pcm_dsnoop.c b/src/pcm/pcm_dsnoop.c
> index 1aedf3c..85f0ff4 100644
> --- a/src/pcm/pcm_dsnoop.c
> +++ b/src/pcm/pcm_dsnoop.c
> @@ -606,6 +606,7 @@ int snd_pcm_dsnoop_open(snd_pcm_t **pcmp, const char *name,
> dsnoop->state = SND_PCM_STATE_OPEN;
> dsnoop->slowptr = opts->slowptr;
> dsnoop->max_periods = opts->max_periods;
> + dsnoop->var_periodsize = opts->var_periodsize;
> dsnoop->sync_ptr = snd_pcm_dsnoop_sync_ptr;
>
> retry:
> --
> 1.7.9.5
>
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