From 050a3a99e1d151b4f55c89f82073ef33f3399646 Mon Sep 17 00:00:00 2001 From: Lennart Poettering Date: Mon, 24 Aug 2009 03:26:56 +0200 Subject: alsa: automatically decrease watermark after a time of stability --- src/modules/alsa/alsa-sink.c | 146 +++++++++++++++++++++++++++++++++---------- 1 file changed, 112 insertions(+), 34 deletions(-) (limited to 'src/modules/alsa/alsa-sink.c') diff --git a/src/modules/alsa/alsa-sink.c b/src/modules/alsa/alsa-sink.c index b99ed782..07d53880 100644 --- a/src/modules/alsa/alsa-sink.c +++ b/src/modules/alsa/alsa-sink.c @@ -62,14 +62,21 @@ /* #define DEBUG_TIMING */ #define DEFAULT_DEVICE "default" -#define DEFAULT_TSCHED_BUFFER_USEC (2*PA_USEC_PER_SEC) /* 2s -- Overall buffer size */ -#define DEFAULT_TSCHED_WATERMARK_USEC (20*PA_USEC_PER_MSEC) /* 20ms -- Fill up when only this much is left in the buffer */ -#define TSCHED_WATERMARK_STEP_USEC (10*PA_USEC_PER_MSEC) /* 10ms -- On underrun, increase watermark by this */ -#define TSCHED_MIN_SLEEP_USEC (10*PA_USEC_PER_MSEC) /* 10ms -- Sleep at least 10ms on each iteration */ -#define TSCHED_MIN_WAKEUP_USEC (4*PA_USEC_PER_MSEC) /* 4ms -- Wakeup at least this long before the buffer runs empty*/ -#define SMOOTHER_MIN_INTERVAL (2*PA_USEC_PER_MSEC) /* 2ms -- min smoother update interval */ -#define SMOOTHER_MAX_INTERVAL (200*PA_USEC_PER_MSEC) /* 200ms -- max smoother update inteval */ +#define DEFAULT_TSCHED_BUFFER_USEC (2*PA_USEC_PER_SEC) /* 2s -- Overall buffer size */ +#define DEFAULT_TSCHED_WATERMARK_USEC (20*PA_USEC_PER_MSEC) /* 20ms -- Fill up when only this much is left in the buffer */ + +#define TSCHED_WATERMARK_INC_STEP_USEC (10*PA_USEC_PER_MSEC) /* 10ms -- On underrun, increase watermark by this */ +#define TSCHED_WATERMARK_DEC_STEP_USEC (5*PA_USEC_PER_MSEC) /* 5ms -- When everything's great, decrease watermark by this */ +#define TSCHED_WATERMARK_VERIFY_AFTER_USEC (20*PA_USEC_PER_SEC) /* 20s -- How long after a drop out recheck if things are good now */ +#define TSCHED_WATERMARK_INC_THRESHOLD_USEC (1*PA_USEC_PER_MSEC) /* 3ms -- If the buffer level ever below this theshold, increase the watermark */ +#define TSCHED_WATERMARK_DEC_THRESHOLD_USEC (100*PA_USEC_PER_MSEC) /* 100ms -- If the buffer level didn't drop below this theshold in the verification time, decrease the watermark */ + +#define TSCHED_MIN_SLEEP_USEC (10*PA_USEC_PER_MSEC) /* 10ms -- Sleep at least 10ms on each iteration */ +#define TSCHED_MIN_WAKEUP_USEC (4*PA_USEC_PER_MSEC) /* 4ms -- Wakeup at least this long before the buffer runs empty*/ + +#define SMOOTHER_MIN_INTERVAL (2*PA_USEC_PER_MSEC) /* 2ms -- min smoother update interval */ +#define SMOOTHER_MAX_INTERVAL (200*PA_USEC_PER_MSEC) /* 200ms -- max smoother update inteval */ #define VOLUME_ACCURACY (PA_VOLUME_NORM/100) /* don't require volume adjustments to be perfectly correct. don't necessarily extend granularity in software unless the differences get greater than this level */ @@ -99,7 +106,12 @@ struct userdata { hwbuf_unused, min_sleep, min_wakeup, - watermark_step; + watermark_inc_step, + watermark_dec_step, + watermark_inc_threshold, + watermark_dec_threshold; + + pa_usec_t watermark_dec_not_before; unsigned nfragments; pa_memchunk memchunk; @@ -248,6 +260,7 @@ static void fix_min_sleep_wakeup(struct userdata *u) { size_t max_use, max_use_2; pa_assert(u); + pa_assert(u->use_tsched); max_use = u->hwbuf_size - u->hwbuf_unused; max_use_2 = pa_frame_align(max_use/2, &u->sink->sample_spec); @@ -262,6 +275,7 @@ static void fix_min_sleep_wakeup(struct userdata *u) { static void fix_tsched_watermark(struct userdata *u) { size_t max_use; pa_assert(u); + pa_assert(u->use_tsched); max_use = u->hwbuf_size - u->hwbuf_unused; @@ -272,7 +286,7 @@ static void fix_tsched_watermark(struct userdata *u) { u->tsched_watermark = u->min_wakeup; } -static void adjust_after_underrun(struct userdata *u) { +static void increase_watermark(struct userdata *u) { size_t old_watermark; pa_usec_t old_min_latency, new_min_latency; @@ -281,31 +295,64 @@ static void adjust_after_underrun(struct userdata *u) { /* First, just try to increase the watermark */ old_watermark = u->tsched_watermark; - u->tsched_watermark = PA_MIN(u->tsched_watermark * 2, u->tsched_watermark + u->watermark_step); + u->tsched_watermark = PA_MIN(u->tsched_watermark * 2, u->tsched_watermark + u->watermark_inc_step); fix_tsched_watermark(u); if (old_watermark != u->tsched_watermark) { - pa_log_notice("Increasing wakeup watermark to %0.2f ms", - (double) pa_bytes_to_usec(u->tsched_watermark, &u->sink->sample_spec) / PA_USEC_PER_MSEC); + pa_log_info("Increasing wakeup watermark to %0.2f ms", + (double) pa_bytes_to_usec(u->tsched_watermark, &u->sink->sample_spec) / PA_USEC_PER_MSEC); return; } /* Hmm, we cannot increase the watermark any further, hence let's raise the latency */ old_min_latency = u->sink->thread_info.min_latency; - new_min_latency = PA_MIN(old_min_latency * 2, old_min_latency + TSCHED_WATERMARK_STEP_USEC); + new_min_latency = PA_MIN(old_min_latency * 2, old_min_latency + TSCHED_WATERMARK_INC_STEP_USEC); new_min_latency = PA_MIN(new_min_latency, u->sink->thread_info.max_latency); if (old_min_latency != new_min_latency) { - pa_log_notice("Increasing minimal latency to %0.2f ms", - (double) new_min_latency / PA_USEC_PER_MSEC); + pa_log_info("Increasing minimal latency to %0.2f ms", + (double) new_min_latency / PA_USEC_PER_MSEC); pa_sink_set_latency_range_within_thread(u->sink, new_min_latency, u->sink->thread_info.max_latency); - return; } /* When we reach this we're officialy fucked! */ } +static void decrease_watermark(struct userdata *u) { + size_t old_watermark; + pa_usec_t now; + + pa_assert(u); + pa_assert(u->use_tsched); + + now = pa_rtclock_now(); + + if (u->watermark_dec_not_before <= 0) + goto restart; + + if (u->watermark_dec_not_before > now) + return; + + old_watermark = u->tsched_watermark; + + if (u->tsched_watermark < u->watermark_dec_step) + u->tsched_watermark = u->tsched_watermark / 2; + else + u->tsched_watermark = PA_MAX(u->tsched_watermark / 2, u->tsched_watermark - u->watermark_dec_step); + + fix_tsched_watermark(u); + + if (old_watermark != u->tsched_watermark) + pa_log_info("Decreasing wakeup watermark to %0.2f ms", + (double) pa_bytes_to_usec(u->tsched_watermark, &u->sink->sample_spec) / PA_USEC_PER_MSEC); + + /* We don't change the latency range*/ + +restart: + u->watermark_dec_not_before = now + TSCHED_WATERMARK_VERIFY_AFTER_USEC; +} + static void hw_sleep_time(struct userdata *u, pa_usec_t *sleep_usec, pa_usec_t*process_usec) { pa_usec_t usec, wm; @@ -313,6 +360,7 @@ static void hw_sleep_time(struct userdata *u, pa_usec_t *sleep_usec, pa_usec_t*p pa_assert(process_usec); pa_assert(u); + pa_assert(u->use_tsched); usec = pa_sink_get_requested_latency_within_thread(u->sink); @@ -360,7 +408,7 @@ static int try_recover(struct userdata *u, const char *call, int err) { return 0; } -static size_t check_left_to_play(struct userdata *u, size_t n_bytes) { +static size_t check_left_to_play(struct userdata *u, size_t n_bytes, pa_bool_t on_timeout) { size_t left_to_play; /* We use <= instead of < for this check here because an underrun @@ -368,34 +416,55 @@ static size_t check_left_to_play(struct userdata *u, size_t n_bytes) { * it is removed from the buffer. This is particularly important * when block transfer is used. */ - if (n_bytes <= u->hwbuf_size) { + if (n_bytes <= u->hwbuf_size) left_to_play = u->hwbuf_size - n_bytes; + else { + + /* We got a dropout. What a mess! */ + left_to_play = 0; #ifdef DEBUG_TIMING - pa_log_debug("%0.2f ms left to play", (double) pa_bytes_to_usec(left_to_play, &u->sink->sample_spec) / PA_USEC_PER_MSEC); + PA_DEBUG_TRAP; #endif - } else { - left_to_play = 0; + if (!u->first && !u->after_rewind) + if (pa_log_ratelimit()) + pa_log_info("Underrun!"); + } #ifdef DEBUG_TIMING - PA_DEBUG_TRAP; + pa_log_debug("%0.2f ms left to play; inc threshold = %0.2f ms; dec threshold = %0.2f ms", + (double) pa_bytes_to_usec(left_to_play, &u->sink->sample_spec) / PA_USEC_PER_MSEC, + (double) pa_bytes_to_usec(u->watermark_inc_threshold, &u->sink->sample_spec) / PA_USEC_PER_MSEC, + (double) pa_bytes_to_usec(u->watermark_dec_threshold, &u->sink->sample_spec) / PA_USEC_PER_MSEC); #endif + if (u->use_tsched) { + pa_bool_t reset_not_before = TRUE; + if (!u->first && !u->after_rewind) { + if (left_to_play < u->watermark_inc_threshold) + increase_watermark(u); + else if (left_to_play > u->watermark_dec_threshold) { + reset_not_before = FALSE; - if (pa_log_ratelimit()) - pa_log_info("Underrun!"); + /* We decrease the watermark only if have actually + * been woken up by a timeout. If something else woke + * us up it's too easy to fulfill the deadlines... */ - if (u->use_tsched) - adjust_after_underrun(u); + if (on_timeout) + decrease_watermark(u); + } } + + if (reset_not_before) + u->watermark_dec_not_before = 0; } return left_to_play; } -static int mmap_write(struct userdata *u, pa_usec_t *sleep_usec, pa_bool_t polled) { +static int mmap_write(struct userdata *u, pa_usec_t *sleep_usec, pa_bool_t polled, pa_bool_t on_timeout) { pa_bool_t work_done = TRUE; pa_usec_t max_sleep_usec = 0, process_usec = 0; size_t left_to_play; @@ -430,7 +499,8 @@ static int mmap_write(struct userdata *u, pa_usec_t *sleep_usec, pa_bool_t polle pa_log_debug("avail: %lu", (unsigned long) n_bytes); #endif - left_to_play = check_left_to_play(u, n_bytes); + left_to_play = check_left_to_play(u, n_bytes, on_timeout); + on_timeout = FALSE; if (u->use_tsched) @@ -565,7 +635,7 @@ static int mmap_write(struct userdata *u, pa_usec_t *sleep_usec, pa_bool_t polle return work_done ? 1 : 0; } -static int unix_write(struct userdata *u, pa_usec_t *sleep_usec, pa_bool_t polled) { +static int unix_write(struct userdata *u, pa_usec_t *sleep_usec, pa_bool_t polled, pa_bool_t on_timeout) { pa_bool_t work_done = FALSE; pa_usec_t max_sleep_usec = 0, process_usec = 0; size_t left_to_play; @@ -591,7 +661,8 @@ static int unix_write(struct userdata *u, pa_usec_t *sleep_usec, pa_bool_t polle } n_bytes = (size_t) n * u->frame_size; - left_to_play = check_left_to_play(u, n_bytes); + left_to_play = check_left_to_play(u, n_bytes, on_timeout); + on_timeout = FALSE; if (u->use_tsched) @@ -1278,15 +1349,16 @@ static void thread_func(void *userdata) { if (PA_SINK_IS_OPENED(u->sink->thread_info.state)) { int work_done; pa_usec_t sleep_usec = 0; + pa_bool_t on_timeout = pa_rtpoll_timer_elapsed(u->rtpoll); if (PA_UNLIKELY(u->sink->thread_info.rewind_requested)) if (process_rewind(u) < 0) goto fail; if (u->use_mmap) - work_done = mmap_write(u, &sleep_usec, revents & POLLOUT); + work_done = mmap_write(u, &sleep_usec, revents & POLLOUT, on_timeout); else - work_done = unix_write(u, &sleep_usec, revents & POLLOUT); + work_done = unix_write(u, &sleep_usec, revents & POLLOUT, on_timeout); if (work_done < 0) goto fail; @@ -1787,7 +1859,6 @@ pa_sink *pa_alsa_sink_new(pa_module *m, pa_modargs *ma, const char*driver, pa_ca u->fragment_size = frag_size = (uint32_t) (period_frames * frame_size); u->nfragments = nfrags; u->hwbuf_size = u->fragment_size * nfrags; - u->tsched_watermark = pa_usec_to_bytes_round_up(pa_bytes_to_usec_round_up(tsched_watermark, &requested_ss), &u->sink->sample_spec); pa_cvolume_mute(&u->hardware_volume, u->sink->sample_spec.channels); pa_log_info("Using %u fragments of size %lu bytes, buffer time is %0.2fms", @@ -1798,7 +1869,13 @@ pa_sink *pa_alsa_sink_new(pa_module *m, pa_modargs *ma, const char*driver, pa_ca pa_sink_set_max_rewind(u->sink, u->hwbuf_size); if (u->use_tsched) { - u->watermark_step = pa_usec_to_bytes(TSCHED_WATERMARK_STEP_USEC, &u->sink->sample_spec); + u->tsched_watermark = pa_usec_to_bytes_round_up(pa_bytes_to_usec_round_up(tsched_watermark, &requested_ss), &u->sink->sample_spec); + + u->watermark_inc_step = pa_usec_to_bytes(TSCHED_WATERMARK_INC_STEP_USEC, &u->sink->sample_spec); + u->watermark_dec_step = pa_usec_to_bytes(TSCHED_WATERMARK_DEC_STEP_USEC, &u->sink->sample_spec); + + u->watermark_inc_threshold = pa_usec_to_bytes_round_up(TSCHED_WATERMARK_INC_THRESHOLD_USEC, &u->sink->sample_spec); + u->watermark_dec_threshold = pa_usec_to_bytes_round_up(TSCHED_WATERMARK_DEC_THRESHOLD_USEC, &u->sink->sample_spec); fix_min_sleep_wakeup(u); fix_tsched_watermark(u); @@ -1812,6 +1889,7 @@ pa_sink *pa_alsa_sink_new(pa_module *m, pa_modargs *ma, const char*driver, pa_ca } else pa_sink_set_fixed_latency(u->sink, pa_bytes_to_usec(u->hwbuf_size, &ss)); + reserve_update(u); if (update_sw_params(u) < 0) -- cgit