On 15.02.2018 12:50, Raman Shyshniou wrote:
> Currently loopback module indefinitely increased latency if underruns
> occurs. This patch allows to set up the upper limit of latency.
> ---
> src/modules/module-loopback.c | 34 ++++++++++++++++++++++++++++++----
> 1 file changed, 30 insertions(+), 4 deletions(-)
>
> diff --git a/src/modules/module-loopback.c b/src/modules/module-loopback.c
> index aecac0a..052d255 100644
> --- a/src/modules/module-loopback.c
> +++ b/src/modules/module-loopback.c
> @@ -45,6 +45,7 @@ PA_MODULE_USAGE(
> "sink=<sink to connect to> "
> "adjust_time=<how often to readjust rates in s> "
> "latency_msec=<latency in ms> "
> + "max_latency_msec=<maximum latency in ms> "
> "format=<sample format> "
> "rate=<sample rate> "
> "channels=<number of channels> "
> @@ -89,6 +90,7 @@ struct userdata {
>
> /* Values from command line configuration */
> pa_usec_t latency;
> + pa_usec_t max_latency;
> pa_usec_t adjust_time;
>
> /* Latency boundaries and current values */
> @@ -158,6 +160,7 @@ static const char* const valid_modargs[] = {
> "sink",
> "adjust_time",
> "latency_msec",
> + "max_latency_msec",
> "format",
> "rate",
> "channels",
> @@ -325,10 +328,20 @@ static void adjust_rates(struct userdata *u) {
>
> /* If we are seeing underruns then the latency is too small */
> if (u->underrun_counter > 2) {
> - u->underrun_latency_limit = PA_MAX(u->latency, u->minimum_latency) + 5 * PA_USEC_PER_MSEC;
> - u->underrun_latency_limit = PA_CLIP_SUB((int64_t)u->underrun_latency_limit, u->sink_latency_offset + u->source_latency_offset);
> + pa_usec_t target_latency;
> +
> + target_latency = PA_MAX(u->latency, u->minimum_latency) + 5 * PA_USEC_PER_MSEC;
> +
> + if (u->max_latency == 0 || target_latency < u->max_latency) {
> + u->underrun_latency_limit = PA_CLIP_SUB((int64_t)target_latency, u->sink_latency_offset + u->source_latency_offset);
> + pa_log_warn("Too many underruns, increasing latency to %0.2f ms", (double)u->underrun_latency_limit / PA_USEC_PER_MSEC);
You have to use target_latency here ...
> + } else {
> + u->underrun_latency_limit = PA_CLIP_SUB((int64_t)u->max_latency, u->sink_latency_offset + u->source_latency_offset);
> + pa_log_warn("Too many underruns, configured maximum latency of %0.2f ms is reached", (double)u->underrun_latency_limit / PA_USEC_PER_MSEC);
and u->max_latency here. Otherwise looks good.
> + pa_log_warn("Consider increasing the max_latency_msec");
> + }
> +
> update_minimum_latency(u, u->sink_input->sink, false);
> - pa_log_warn("Too many underruns, increasing latency to %0.2f ms", (double)u->minimum_latency / PA_USEC_PER_MSEC);
> u->underrun_counter = 0;
> }
>
> @@ -347,7 +360,7 @@ static void adjust_rates(struct userdata *u) {
> }
> u->adjust_time_stamp = now;
>
> - /* Rates and latencies*/
> + /* Rates and latencies */
> old_rate = u->sink_input->sample_spec.rate;
> base_rate = u->source_output->sample_spec.rate;
>
> @@ -1252,6 +1265,7 @@ int pa__init(pa_module *m) {
> pa_source_output_new_data source_output_data;
> bool source_dont_move;
> uint32_t latency_msec;
> + uint32_t max_latency_msec;
> pa_sample_spec ss;
> pa_channel_map map;
> bool format_set = false;
> @@ -1336,10 +1350,22 @@ int pa__init(pa_module *m) {
> goto fail;
> }
>
> + max_latency_msec = 0;
> + if (pa_modargs_get_value_u32(ma, "max_latency_msec", &max_latency_msec) < 0) {
> + pa_log("Invalid maximum latency specification");
> + goto fail;
> + }
> +
> + if (max_latency_msec > 0 && max_latency_msec < latency_msec) {
> + pa_log_warn("Configured maximum latency is smaller than latency, using latency instead");
> + max_latency_msec = latency_msec;
> + }
> +
> m->userdata = u = pa_xnew0(struct userdata, 1);
> u->core = m->core;
> u->module = m;
> u->latency = (pa_usec_t) latency_msec * PA_USEC_PER_MSEC;
> + u->max_latency = (pa_usec_t) max_latency_msec * PA_USEC_PER_MSEC;
> u->output_thread_info.pop_called = false;
> u->output_thread_info.pop_adjust = false;
> u->output_thread_info.push_called = false;
