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mpv/stream/cache.c
wm4 7eccb62f85 cache: change license to LGPL v3
All authors have agreed to the relicensing.

iive has insisted on "LGPL v3 or later", which makes the file LGPL v3.
His commits are the following: 84ec577508 9b0d8c680f. All other
contributions are LGPL v2.1. I hope we can remove these changes
completely one day to make this file LGPL v2.1.

iive also authored commit 3934b160a8, but this code is completely gone
today. (fork() and shared memory use was removed completely in favor of
threads.)
2017-05-08 12:56:29 +02:00

751 lines
24 KiB
C

/*
* This file is part of mpv.
*
* mpv is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 3 of the License, or (at your option) any later version.
*
* mpv is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with mpv. If not, see <http://www.gnu.org/licenses/>.
*
* The parts making this file LGPL v3 (instead of v2.1 or later) are:
* 84ec57750883 remove unused cache-prefill and create cache-seek-min that...
* 9b0d8c680f63 cache min fill adjustment, based on patch by Jeremy Huddleston
* (iive agreed to LGPL v3+ only. Jeremy agreed to LGPL v2.1 or later.)
*/
// Time in seconds the main thread waits for the cache thread. On wakeups, the
// code checks for user requested aborts and also prints warnings that the
// cache is being slow.
#define CACHE_WAIT_TIME 1.0
// The time the cache sleeps in idle mode. This controls how often the cache
// retries reading from the stream after EOF has reached (in case the stream is
// actually readable again, for example if data has been appended to a file).
// Note that if this timeout is too low, the player will waste too much CPU
// when player is paused.
#define CACHE_IDLE_SLEEP_TIME 1.0
// Time in seconds the cache updates "cached" controls. Note that idle mode
// will block the cache from doing this, and this timeout is honored only if
// the cache is active.
#define CACHE_UPDATE_CONTROLS_TIME 2.0
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <unistd.h>
#include <errno.h>
#include <assert.h>
#include <pthread.h>
#include <time.h>
#include <math.h>
#include <sys/time.h>
#include <libavutil/common.h>
#include "config.h"
#include "osdep/timer.h"
#include "osdep/threads.h"
#include "common/msg.h"
#include "common/tags.h"
#include "options/options.h"
#include "stream.h"
#include "common/common.h"
// Note: (struct priv*)(cache->priv)->cache == cache
struct priv {
pthread_t cache_thread;
bool cache_thread_running;
pthread_mutex_t mutex;
pthread_cond_t wakeup;
// Constants (as long as cache thread is running)
// Some of these might actually be changed by a synced cache resize.
unsigned char *buffer; // base pointer of the allocated buffer memory
int64_t buffer_size; // size of the allocated buffer memory
int64_t back_size; // keep back_size amount of old bytes for backward seek
int64_t seek_limit; // keep filling cache if distance is less that seek limit
bool seekable; // underlying stream is seekable
struct mp_log *log;
// Owned by the main thread
stream_t *cache; // wrapper stream, used by demuxer etc.
// Owned by the cache thread
stream_t *stream; // "real" stream, used to read from the source media
// All the following members are shared between the threads.
// You must lock the mutex to access them.
// Ringbuffer
int64_t min_filepos; // range of file that is cached in the buffer
int64_t max_filepos; // ... max_filepos being the last read position
bool eof; // true if max_filepos = EOF
int64_t offset; // buffer[WRAP(s->max_filepos - offset)] corresponds
// to the byte at max_filepos (must be wrapped by
// buffer_size)
bool idle; // cache thread has stopped reading
int64_t reads; // number of actual read attempts performed
int64_t speed_start; // start time (us) for calculating download speed
int64_t speed_amount; // bytes read since speed_start
double speed;
bool enable_readahead; // actively read beyond read() position
int64_t read_filepos; // client read position (mirrors cache->pos)
int64_t read_min; // file position until which the thread should
// read even if readahead is disabled
int64_t eof_pos;
int control; // requested STREAM_CTRL_... or CACHE_CTRL_...
void *control_arg; // temporary for executing STREAM_CTRLs
int control_res;
bool control_flush;
// Cached STREAM_CTRLs
double stream_time_length;
int64_t stream_size;
struct mp_tags *stream_metadata;
double start_pts;
bool has_avseek;
};
enum {
CACHE_CTRL_NONE = 0,
CACHE_CTRL_QUIT = -1,
CACHE_CTRL_PING = -2,
CACHE_CTRL_SEEK = -3,
// we should fill buffer only if space>=FILL_LIMIT
FILL_LIMIT = 16 * 1024,
};
// Used by the main thread to wakeup the cache thread, and to wait for the
// cache thread. The cache mutex has to be locked when calling this function.
// *retry_time should be set to 0 on the first call.
// Return false if the stream has been aborted.
static bool cache_wakeup_and_wait(struct priv *s, double *retry_time)
{
double start = mp_time_sec();
if (*retry_time >= CACHE_WAIT_TIME) {
MP_VERBOSE(s, "Cache is not responding - slow/stuck network connection?\n");
*retry_time = -1; // do not warn again for this call
}
pthread_cond_signal(&s->wakeup);
struct timespec ts = mp_rel_time_to_timespec(CACHE_WAIT_TIME);
pthread_cond_timedwait(&s->wakeup, &s->mutex, &ts);
if (*retry_time >= 0)
*retry_time += mp_time_sec() - start;
return !mp_cancel_test(s->cache->cancel);
}
// Runs in the cache thread
static void cache_drop_contents(struct priv *s)
{
s->offset = s->min_filepos = s->max_filepos = s->read_filepos;
s->eof = false;
s->start_pts = MP_NOPTS_VALUE;
}
static void update_speed(struct priv *s)
{
int64_t now = mp_time_us();
if (s->speed_start + 1000000 <= now) {
s->speed = s->speed_amount * 1e6 / (now - s->speed_start);
s->speed_amount = 0;
s->speed_start = now;
}
}
// Copy at most dst_size from the cache at the given absolute file position pos.
// Return number of bytes that could actually be read.
// Does not advance the file position, or change anything else.
// Can be called from anywhere, as long as the mutex is held.
static size_t read_buffer(struct priv *s, unsigned char *dst,
size_t dst_size, int64_t pos)
{
size_t read = 0;
while (read < dst_size) {
if (pos >= s->max_filepos || pos < s->min_filepos)
break;
int64_t newb = s->max_filepos - pos; // new bytes in the buffer
int64_t bpos = pos - s->offset; // file pos to buffer memory pos
if (bpos < 0) {
bpos += s->buffer_size;
} else if (bpos >= s->buffer_size) {
bpos -= s->buffer_size;
}
if (newb > s->buffer_size - bpos)
newb = s->buffer_size - bpos; // handle wrap...
newb = MPMIN(newb, dst_size - read);
assert(newb >= 0 && read + newb <= dst_size);
assert(bpos >= 0 && bpos + newb <= s->buffer_size);
memcpy(&dst[read], &s->buffer[bpos], newb);
read += newb;
pos += newb;
}
return read;
}
static bool cache_update_stream_position(struct priv *s)
{
int64_t read = s->read_filepos;
// drop cache contents only if seeking backward or too much fwd.
// This is also done for on-disk files, since it loses the backseek cache.
// That in turn can cause major bandwidth increase and performance
// issues with e.g. mov or badly interleaved files
if (read < s->min_filepos || read > s->max_filepos + s->seek_limit) {
MP_VERBOSE(s, "Dropping cache at pos %"PRId64", "
"cached range: %"PRId64"-%"PRId64".\n", read,
s->min_filepos, s->max_filepos);
cache_drop_contents(s);
}
if (stream_tell(s->stream) != s->max_filepos && s->seekable) {
MP_VERBOSE(s, "Seeking underlying stream: %"PRId64" -> %"PRId64"\n",
stream_tell(s->stream), s->max_filepos);
if (!stream_seek(s->stream, s->max_filepos))
return false;
}
return stream_tell(s->stream) == s->max_filepos;
}
// Runs in the cache thread.
static void cache_fill(struct priv *s)
{
int64_t read = s->read_filepos;
bool read_attempted = false;
int len = 0;
if (!cache_update_stream_position(s))
goto done;
if (!s->enable_readahead && s->read_min <= s->max_filepos)
goto done;
if (mp_cancel_test(s->cache->cancel))
goto done;
// number of buffer bytes which should be preserved in backwards direction
int64_t back = MPCLAMP(read - s->min_filepos, 0, s->back_size);
// limit maximum readahead so that the backbuffer space is reserved, even
// if the backbuffer is not used. limit it to ensure that we don't stall the
// network when starting a file, or we wouldn't download new data until we
// get new free space again. (unless everything fits in the cache.)
if (s->stream_size > s->buffer_size)
back = MPMAX(back, s->back_size);
// number of buffer bytes that are valid and can be read
int64_t newb = FFMAX(s->max_filepos - read, 0);
// max. number of bytes that can be written (starting from max_filepos)
int64_t space = s->buffer_size - (newb + back);
// offset into the buffer that maps to max_filepos
int64_t pos = s->max_filepos - s->offset;
if (pos >= s->buffer_size)
pos -= s->buffer_size; // wrap-around
if (space < FILL_LIMIT)
goto done;
// limit to end of buffer (without wrapping)
if (pos + space >= s->buffer_size)
space = s->buffer_size - pos;
// limit read size (or else would block and read the entire buffer in 1 call)
space = FFMIN(space, s->stream->read_chunk);
// back+newb+space <= buffer_size
int64_t back2 = s->buffer_size - (space + newb); // max back size
if (s->min_filepos < (read - back2))
s->min_filepos = read - back2;
// The read call might take a long time and block, so drop the lock.
pthread_mutex_unlock(&s->mutex);
len = stream_read_partial(s->stream, &s->buffer[pos], space);
pthread_mutex_lock(&s->mutex);
// Do this after reading a block, because at least libdvdnav updates the
// stream position only after actually reading something after a seek.
if (s->start_pts == MP_NOPTS_VALUE) {
double pts;
if (stream_control(s->stream, STREAM_CTRL_GET_CURRENT_TIME, &pts) > 0)
s->start_pts = pts;
}
s->max_filepos += len;
if (pos + len == s->buffer_size)
s->offset += s->buffer_size; // wrap...
s->speed_amount += len;
read_attempted = true;
done: ;
bool prev_eof = s->eof;
if (read_attempted)
s->eof = len <= 0;
if (!prev_eof && s->eof) {
s->eof_pos = stream_tell(s->stream);
MP_VERBOSE(s, "EOF reached.\n");
}
s->idle = s->eof || !read_attempted;
s->reads++;
update_speed(s);
pthread_cond_signal(&s->wakeup);
}
// This is called both during init and at runtime.
// The size argument is the readahead half only; s->back_size is the backbuffer.
static int resize_cache(struct priv *s, int64_t size)
{
int64_t min_size = FILL_LIMIT * 2;
int64_t max_size = ((size_t)-1) / 8;
if (s->stream_size > 0) {
size = MPMIN(size, s->stream_size);
if (size >= s->stream_size) {
MP_VERBOSE(s, "no backbuffer needed\n");
s->back_size = 0;
}
}
int64_t buffer_size = MPCLAMP(size, min_size, max_size);
s->back_size = MPCLAMP(s->back_size, min_size, max_size);
buffer_size += s->back_size;
unsigned char *buffer = malloc(buffer_size);
if (!buffer)
return STREAM_ERROR;
if (s->buffer) {
// Copy & free the old ringbuffer data.
// If the buffer is too small, prefer to copy these regions:
// 1. Data starting from read_filepos, until cache end
size_t read_1 = read_buffer(s, buffer, buffer_size, s->read_filepos);
// 2. then data from before read_filepos until cache start
// (this one needs to be copied to the end of the ringbuffer)
size_t read_2 = 0;
if (s->min_filepos < s->read_filepos) {
size_t copy_len = buffer_size - read_1;
copy_len = MPMIN(copy_len, s->read_filepos - s->min_filepos);
assert(copy_len + read_1 <= buffer_size);
read_2 = read_buffer(s, buffer + buffer_size - copy_len, copy_len,
s->read_filepos - copy_len);
// This shouldn't happen, unless copy_len was computed incorrectly.
assert(read_2 == copy_len);
}
// Set it up such that read_1 is at buffer pos 0, and read_2 wraps
// around below it, so that it is located at the end of the buffer.
s->min_filepos = s->read_filepos - read_2;
s->max_filepos = s->read_filepos + read_1;
s->offset = s->max_filepos - read_1;
} else {
cache_drop_contents(s);
}
free(s->buffer);
s->buffer_size = buffer_size;
s->buffer = buffer;
s->idle = false;
s->eof = false;
//make sure that we won't wait from cache_fill
//more data than it is allowed to fill
if (s->seek_limit > s->buffer_size - FILL_LIMIT)
s->seek_limit = s->buffer_size - FILL_LIMIT;
MP_VERBOSE(s, "Cache size set to %lld KiB (%lld KiB backbuffer)\n",
(long long)(s->buffer_size / 1024),
(long long)(s->back_size / 1024));
assert(s->back_size < s->buffer_size);
return STREAM_OK;
}
static void update_cached_controls(struct priv *s)
{
int64_t i64;
double d;
struct mp_tags *tags;
s->stream_time_length = 0;
if (stream_control(s->stream, STREAM_CTRL_GET_TIME_LENGTH, &d) == STREAM_OK)
s->stream_time_length = d;
if (stream_control(s->stream, STREAM_CTRL_GET_METADATA, &tags) == STREAM_OK) {
talloc_free(s->stream_metadata);
s->stream_metadata = talloc_steal(s, tags);
}
s->stream_size = s->eof_pos;
i64 = stream_get_size(s->stream);
if (i64 >= 0)
s->stream_size = i64;
s->has_avseek = stream_control(s->stream, STREAM_CTRL_HAS_AVSEEK, NULL) > 0;
}
// the core might call these every frame, so cache them...
static int cache_get_cached_control(stream_t *cache, int cmd, void *arg)
{
struct priv *s = cache->priv;
switch (cmd) {
case STREAM_CTRL_GET_CACHE_INFO:
*(struct stream_cache_info *)arg = (struct stream_cache_info) {
.size = s->buffer_size - s->back_size,
.fill = s->max_filepos - s->read_filepos,
.idle = s->idle,
.speed = llrint(s->speed),
};
return STREAM_OK;
case STREAM_CTRL_SET_READAHEAD:
s->enable_readahead = *(int *)arg;
pthread_cond_signal(&s->wakeup);
return STREAM_OK;
case STREAM_CTRL_GET_TIME_LENGTH:
*(double *)arg = s->stream_time_length;
return s->stream_time_length ? STREAM_OK : STREAM_UNSUPPORTED;
case STREAM_CTRL_GET_SIZE:
if (s->stream_size < 0)
return STREAM_UNSUPPORTED;
*(int64_t *)arg = s->stream_size;
return STREAM_OK;
case STREAM_CTRL_GET_CURRENT_TIME: {
if (s->start_pts == MP_NOPTS_VALUE)
return STREAM_UNSUPPORTED;
*(double *)arg = s->start_pts;
return STREAM_OK;
}
case STREAM_CTRL_HAS_AVSEEK:
return s->has_avseek ? STREAM_OK : STREAM_UNSUPPORTED;
case STREAM_CTRL_GET_METADATA: {
if (s->stream_metadata) {
ta_set_parent(s->stream_metadata, NULL);
*(struct mp_tags **)arg = s->stream_metadata;
s->stream_metadata = NULL;
return STREAM_OK;
}
return STREAM_UNSUPPORTED;
}
case STREAM_CTRL_AVSEEK:
if (!s->has_avseek)
return STREAM_UNSUPPORTED;
break;
}
return STREAM_ERROR;
}
static bool control_needs_flush(int stream_ctrl)
{
switch (stream_ctrl) {
case STREAM_CTRL_SEEK_TO_TIME:
case STREAM_CTRL_AVSEEK:
case STREAM_CTRL_SET_ANGLE:
case STREAM_CTRL_SET_CURRENT_TITLE:
case STREAM_CTRL_RECONNECT:
case STREAM_CTRL_DVB_SET_CHANNEL:
case STREAM_CTRL_DVB_SET_CHANNEL_NAME:
case STREAM_CTRL_DVB_STEP_CHANNEL:
return true;
}
return false;
}
// Runs in the cache thread
static void cache_execute_control(struct priv *s)
{
uint64_t old_pos = stream_tell(s->stream);
s->control_flush = false;
switch (s->control) {
case STREAM_CTRL_SET_CACHE_SIZE:
s->control_res = resize_cache(s, *(int64_t *)s->control_arg);
break;
default:
s->control_res = stream_control(s->stream, s->control, s->control_arg);
}
bool pos_changed = old_pos != stream_tell(s->stream);
bool ok = s->control_res == STREAM_OK;
if (pos_changed && !ok) {
MP_ERR(s, "STREAM_CTRL changed stream pos but "
"returned error, this is not allowed!\n");
} else if (pos_changed || (ok && control_needs_flush(s->control))) {
MP_VERBOSE(s, "Dropping cache due to control()\n");
s->read_filepos = stream_tell(s->stream);
s->read_min = s->read_filepos;
s->control_flush = true;
cache_drop_contents(s);
}
update_cached_controls(s);
s->control = CACHE_CTRL_NONE;
pthread_cond_signal(&s->wakeup);
}
static void *cache_thread(void *arg)
{
struct priv *s = arg;
mpthread_set_name("cache");
pthread_mutex_lock(&s->mutex);
update_cached_controls(s);
double last = mp_time_sec();
while (s->control != CACHE_CTRL_QUIT) {
if (mp_time_sec() - last > CACHE_UPDATE_CONTROLS_TIME) {
update_cached_controls(s);
last = mp_time_sec();
}
if (s->control > 0) {
cache_execute_control(s);
} else if (s->control == CACHE_CTRL_SEEK) {
s->control_res = cache_update_stream_position(s);
s->control = CACHE_CTRL_NONE;
pthread_cond_signal(&s->wakeup);
} else {
cache_fill(s);
}
if (s->control == CACHE_CTRL_PING) {
pthread_cond_signal(&s->wakeup);
s->control = CACHE_CTRL_NONE;
}
if (s->idle && s->control == CACHE_CTRL_NONE) {
struct timespec ts = mp_rel_time_to_timespec(CACHE_IDLE_SLEEP_TIME);
pthread_cond_timedwait(&s->wakeup, &s->mutex, &ts);
}
}
pthread_cond_signal(&s->wakeup);
pthread_mutex_unlock(&s->mutex);
MP_VERBOSE(s, "Cache exiting...\n");
return NULL;
}
static int cache_fill_buffer(struct stream *cache, char *buffer, int max_len)
{
struct priv *s = cache->priv;
assert(s->cache_thread_running);
pthread_mutex_lock(&s->mutex);
if (cache->pos != s->read_filepos)
MP_ERR(s, "!!! read_filepos differs !!! report this bug...\n");
int readb = 0;
if (max_len > 0) {
double retry_time = 0;
int64_t retry = s->reads - 1; // try at least 1 read on EOF
while (1) {
s->read_min = s->read_filepos + max_len + 64 * 1024;
readb = read_buffer(s, buffer, max_len, s->read_filepos);
s->read_filepos += readb;
if (readb > 0)
break;
if (s->eof && s->read_filepos >= s->max_filepos && s->reads >= retry)
break;
s->idle = false;
if (!cache_wakeup_and_wait(s, &retry_time))
break;
}
}
// wakeup the cache thread, possibly make it read more data ahead
pthread_cond_signal(&s->wakeup);
pthread_mutex_unlock(&s->mutex);
return readb;
}
static int cache_seek(stream_t *cache, int64_t pos)
{
struct priv *s = cache->priv;
assert(s->cache_thread_running);
int r = 1;
pthread_mutex_lock(&s->mutex);
MP_DBG(s, "request seek: %" PRId64 " <= to=%" PRId64
" (cur=%" PRId64 ") <= %" PRId64 " \n",
s->min_filepos, pos, s->read_filepos, s->max_filepos);
if (!s->seekable && pos > s->max_filepos) {
MP_ERR(s, "Attempting to seek past cached data in unseekable stream.\n");
r = 0;
} else if (!s->seekable && pos < s->min_filepos) {
MP_ERR(s, "Attempting to seek before cached data in unseekable stream.\n");
r = 0;
} else {
cache->pos = s->read_filepos = s->read_min = pos;
s->eof = false; // so that cache_read() will actually wait for new data
s->control = CACHE_CTRL_SEEK;
s->control_res = 0;
double retry = 0;
while (s->control != CACHE_CTRL_NONE) {
if (!cache_wakeup_and_wait(s, &retry))
break;
}
r = s->control_res;
pthread_cond_signal(&s->wakeup);
}
pthread_mutex_unlock(&s->mutex);
return r;
}
static int cache_control(stream_t *cache, int cmd, void *arg)
{
struct priv *s = cache->priv;
int r = STREAM_ERROR;
assert(cmd > 0);
pthread_mutex_lock(&s->mutex);
r = cache_get_cached_control(cache, cmd, arg);
if (r != STREAM_ERROR)
goto done;
MP_VERBOSE(s, "blocking for STREAM_CTRL %d\n", cmd);
s->control = cmd;
s->control_arg = arg;
double retry = 0;
while (s->control != CACHE_CTRL_NONE) {
if (!cache_wakeup_and_wait(s, &retry)) {
s->eof = 1;
r = STREAM_UNSUPPORTED;
goto done;
}
}
r = s->control_res;
if (s->control_flush) {
stream_drop_buffers(cache);
cache->pos = s->read_filepos;
}
done:
pthread_mutex_unlock(&s->mutex);
return r;
}
static void cache_uninit(stream_t *cache)
{
struct priv *s = cache->priv;
if (s->cache_thread_running) {
MP_VERBOSE(s, "Terminating cache...\n");
pthread_mutex_lock(&s->mutex);
s->control = CACHE_CTRL_QUIT;
pthread_cond_signal(&s->wakeup);
pthread_mutex_unlock(&s->mutex);
pthread_join(s->cache_thread, NULL);
}
pthread_mutex_destroy(&s->mutex);
pthread_cond_destroy(&s->wakeup);
free(s->buffer);
talloc_free(s);
}
// return 1 on success, 0 if the cache is disabled/not needed, and -1 on error
// or if the cache is disabled
int stream_cache_init(stream_t *cache, stream_t *stream,
struct mp_cache_opts *opts)
{
if (opts->size < 1)
return 0;
struct priv *s = talloc_zero(NULL, struct priv);
s->log = cache->log;
s->eof_pos = -1;
s->enable_readahead = true;
cache_drop_contents(s);
s->speed_start = mp_time_us();
s->seek_limit = opts->seek_min * 1024ULL;
s->back_size = opts->back_buffer * 1024ULL;
s->stream_size = stream_get_size(stream);
if (resize_cache(s, opts->size * 1024ULL) != STREAM_OK) {
MP_ERR(s, "Failed to allocate cache buffer.\n");
talloc_free(s);
return -1;
}
pthread_mutex_init(&s->mutex, NULL);
pthread_cond_init(&s->wakeup, NULL);
cache->priv = s;
s->cache = cache;
s->stream = stream;
cache->seek = cache_seek;
cache->fill_buffer = cache_fill_buffer;
cache->control = cache_control;
cache->close = cache_uninit;
int64_t min = opts->initial * 1024ULL;
if (min > s->buffer_size - FILL_LIMIT)
min = s->buffer_size - FILL_LIMIT;
s->seekable = stream->seekable;
if (pthread_create(&s->cache_thread, NULL, cache_thread, s) != 0) {
MP_ERR(s, "Starting cache thread failed.\n");
return -1;
}
s->cache_thread_running = true;
// wait until cache is filled with at least min bytes
if (min < 1)
return 1;
for (;;) {
if (mp_cancel_test(cache->cancel))
return -1;
struct stream_cache_info info;
if (stream_control(s->cache, STREAM_CTRL_GET_CACHE_INFO, &info) < 0)
break;
MP_INFO(s, "\rCache fill: %5.2f%% "
"(%" PRId64 " bytes) ", 100.0 * info.fill / s->buffer_size,
info.fill);
if (info.fill >= min)
break;
if (info.idle)
break; // file is smaller than prefill size
// Wake up if the cache is done reading some data (or on timeout/abort)
pthread_mutex_lock(&s->mutex);
s->control = CACHE_CTRL_PING;
pthread_cond_signal(&s->wakeup);
cache_wakeup_and_wait(s, &(double){0});
pthread_mutex_unlock(&s->mutex);
}
MP_INFO(s, "\n");
return 1;
}