[FFmpeg-devel] [PATCH 16/27] fftools/ffmpeg_demux: switch from AVThreadMessageQueue to ThreadQueue
Anton Khirnov
anton at khirnov.net
Tue Sep 19 22:10:43 EEST 2023
* the code is made shorter and simpler
* avoids constantly allocating and freeing AVPackets, thanks to
ThreadQueue integration with ObjPool
* is consistent with decoding/filtering/muxing
* reduces the diff in the future switch to thread-aware scheduling
This makes ifile_get_packet() always block. Any potential issues caused
by this will be resolved by the switch to thread-aware scheduling in
future commits.
---
fftools/ffmpeg.c | 32 +++++------
fftools/ffmpeg.h | 14 ++++-
fftools/ffmpeg_demux.c | 116 +++++++++++++++-------------------------
fftools/ffmpeg_filter.c | 2 +-
4 files changed, 71 insertions(+), 93 deletions(-)
diff --git a/fftools/ffmpeg.c b/fftools/ffmpeg.c
index 7c33b56cd3..7d6972f689 100644
--- a/fftools/ffmpeg.c
+++ b/fftools/ffmpeg.c
@@ -1029,9 +1029,6 @@ static int check_keyboard_interaction(int64_t cur_time)
static void reset_eagain(void)
{
- int i;
- for (i = 0; i < nb_input_files; i++)
- input_files[i]->eagain = 0;
for (OutputStream *ost = ost_iter(NULL); ost; ost = ost_iter(ost))
ost->unavailable = 0;
}
@@ -1055,19 +1052,14 @@ static void decode_flush(InputFile *ifile)
* this function should be called again
* - AVERROR_EOF -- this function should not be called again
*/
-static int process_input(int file_index)
+static int process_input(int file_index, AVPacket *pkt)
{
InputFile *ifile = input_files[file_index];
InputStream *ist;
- AVPacket *pkt;
int ret, i;
- ret = ifile_get_packet(ifile, &pkt);
+ ret = ifile_get_packet(ifile, pkt);
- if (ret == AVERROR(EAGAIN)) {
- ifile->eagain = 1;
- return ret;
- }
if (ret == 1) {
/* the input file is looped: flush the decoders */
decode_flush(ifile);
@@ -1114,7 +1106,7 @@ static int process_input(int file_index)
ret = process_input_packet(ist, pkt, 0);
- av_packet_free(&pkt);
+ av_packet_unref(pkt);
return ret < 0 ? ret : 0;
}
@@ -1124,7 +1116,7 @@ static int process_input(int file_index)
*
* @return 0 for success, <0 for error
*/
-static int transcode_step(OutputStream *ost)
+static int transcode_step(OutputStream *ost, AVPacket *demux_pkt)
{
InputStream *ist = NULL;
int ret;
@@ -1139,10 +1131,8 @@ static int transcode_step(OutputStream *ost)
av_assert0(ist);
}
- ret = process_input(ist->file_index);
+ ret = process_input(ist->file_index, demux_pkt);
if (ret == AVERROR(EAGAIN)) {
- if (input_files[ist->file_index]->eagain)
- ost->unavailable = 1;
return 0;
}
@@ -1168,12 +1158,19 @@ static int transcode(int *err_rate_exceeded)
int ret = 0, i;
InputStream *ist;
int64_t timer_start;
+ AVPacket *demux_pkt = NULL;
print_stream_maps();
*err_rate_exceeded = 0;
atomic_store(&transcode_init_done, 1);
+ demux_pkt = av_packet_alloc();
+ if (!demux_pkt) {
+ ret = AVERROR(ENOMEM);
+ goto fail;
+ }
+
if (stdin_interaction) {
av_log(NULL, AV_LOG_INFO, "Press [q] to stop, [?] for help\n");
}
@@ -1201,7 +1198,7 @@ static int transcode(int *err_rate_exceeded)
break;
}
- ret = transcode_step(ost);
+ ret = transcode_step(ost, demux_pkt);
if (ret < 0 && ret != AVERROR_EOF) {
av_log(NULL, AV_LOG_ERROR, "Error while filtering: %s\n", av_err2str(ret));
break;
@@ -1242,6 +1239,9 @@ static int transcode(int *err_rate_exceeded)
/* dump report by using the first video and audio streams */
print_report(1, timer_start, av_gettime_relative());
+fail:
+ av_packet_free(&demux_pkt);
+
return ret;
}
diff --git a/fftools/ffmpeg.h b/fftools/ffmpeg.h
index 5a8f52ce00..88b8ed12c0 100644
--- a/fftools/ffmpeg.h
+++ b/fftools/ffmpeg.h
@@ -101,6 +101,17 @@ typedef struct {
} AudioChannelMap;
#endif
+/**
+ * AVPacket.opaque values we use.
+ */
+enum PacketOpaque {
+ /**
+ * Sent by demuxers after seeking, so that decoders should be flushed.
+ * The packet wit this value is otherwise always empty.
+ */
+ PKT_OPAQUE_SEEK = 1,
+};
+
typedef struct DemuxPktData {
// estimated dts in AV_TIME_BASE_Q,
// to be used when real dts is missing
@@ -406,7 +417,6 @@ typedef struct InputFile {
AVFormatContext *ctx;
int eof_reached; /* true if eof reached */
- int eagain; /* true if last read attempt returned EAGAIN */
int64_t input_ts_offset;
int input_sync_ref;
/**
@@ -856,7 +866,7 @@ void ifile_close(InputFile **f);
* caller should flush decoders and read from this demuxer again
* - a negative error code on failure
*/
-int ifile_get_packet(InputFile *f, AVPacket **pkt);
+int ifile_get_packet(InputFile *f, AVPacket *pkt);
int ist_output_add(InputStream *ist, OutputStream *ost);
int ist_filter_add(InputStream *ist, InputFilter *ifilter, int is_simple);
diff --git a/fftools/ffmpeg_demux.c b/fftools/ffmpeg_demux.c
index c01852d4cf..0955956117 100644
--- a/fftools/ffmpeg_demux.c
+++ b/fftools/ffmpeg_demux.c
@@ -20,6 +20,8 @@
#include <stdint.h>
#include "ffmpeg.h"
+#include "objpool.h"
+#include "thread_queue.h"
#include "libavutil/avassert.h"
#include "libavutil/avstring.h"
@@ -32,7 +34,6 @@
#include "libavutil/time.h"
#include "libavutil/timestamp.h"
#include "libavutil/thread.h"
-#include "libavutil/threadmessage.h"
#include "libavcodec/packet.h"
@@ -109,19 +110,13 @@ typedef struct Demuxer {
double readrate_initial_burst;
- AVThreadMessageQueue *in_thread_queue;
+ ThreadQueue *thread_queue;
int thread_queue_size;
pthread_t thread;
- int non_blocking;
int read_started;
} Demuxer;
-typedef struct DemuxMsg {
- AVPacket *pkt;
- int looping;
-} DemuxMsg;
-
static DemuxStream *ds_from_ist(InputStream *ist)
{
return (DemuxStream*)ist;
@@ -456,26 +451,16 @@ static int ts_fixup(Demuxer *d, AVPacket *pkt)
return 0;
}
-// process an input packet into a message to send to the consumer thread
-// src is always cleared by this function
-static int input_packet_process(Demuxer *d, DemuxMsg *msg, AVPacket *src)
+static int input_packet_process(Demuxer *d, AVPacket *pkt)
{
InputFile *f = &d->f;
- InputStream *ist = f->streams[src->stream_index];
+ InputStream *ist = f->streams[pkt->stream_index];
DemuxStream *ds = ds_from_ist(ist);
- AVPacket *pkt;
int ret = 0;
- pkt = av_packet_alloc();
- if (!pkt) {
- av_packet_unref(src);
- return AVERROR(ENOMEM);
- }
- av_packet_move_ref(pkt, src);
-
ret = ts_fixup(d, pkt);
if (ret < 0)
- goto fail;
+ return ret;
ds->data_size += pkt->size;
ds->nb_packets++;
@@ -493,10 +478,8 @@ static int input_packet_process(Demuxer *d, DemuxMsg *msg, AVPacket *src)
continue;
dst_data = av_packet_new_side_data(pkt, src_sd->type, src_sd->size);
- if (!dst_data) {
- ret = AVERROR(ENOMEM);
- goto fail;
- }
+ if (!dst_data)
+ return AVERROR(ENOMEM);
memcpy(dst_data, src_sd->data, src_sd->size);
}
@@ -513,13 +496,7 @@ static int input_packet_process(Demuxer *d, DemuxMsg *msg, AVPacket *src)
av_ts2timestr(input_files[ist->file_index]->ts_offset, &AV_TIME_BASE_Q));
}
- msg->pkt = pkt;
- pkt = NULL;
-
-fail:
- av_packet_free(&pkt);
-
- return ret;
+ return 0;
}
static void readrate_sleep(Demuxer *d)
@@ -569,7 +546,6 @@ static void *input_thread(void *arg)
Demuxer *d = arg;
InputFile *f = &d->f;
AVPacket *pkt;
- unsigned flags = d->non_blocking ? AV_THREAD_MESSAGE_NONBLOCK : 0;
int ret = 0;
pkt = av_packet_alloc();
@@ -585,8 +561,6 @@ static void *input_thread(void *arg)
d->wallclock_start = av_gettime_relative();
while (1) {
- DemuxMsg msg = { NULL };
-
ret = av_read_frame(f->ctx, pkt);
if (ret == AVERROR(EAGAIN)) {
@@ -596,8 +570,8 @@ static void *input_thread(void *arg)
if (ret < 0) {
if (d->loop) {
/* signal looping to the consumer thread */
- msg.looping = 1;
- ret = av_thread_message_queue_send(d->in_thread_queue, &msg, 0);
+ pkt->opaque = (void*)(intptr_t)PKT_OPAQUE_SEEK;
+ ret = tq_send(d->thread_queue, 0, pkt);
if (ret >= 0)
ret = seek_to_start(d);
if (ret >= 0)
@@ -640,35 +614,26 @@ static void *input_thread(void *arg)
}
}
- ret = input_packet_process(d, &msg, pkt);
+ ret = input_packet_process(d, pkt);
if (ret < 0)
break;
if (f->readrate)
readrate_sleep(d);
- ret = av_thread_message_queue_send(d->in_thread_queue, &msg, flags);
- if (flags && ret == AVERROR(EAGAIN)) {
- flags = 0;
- ret = av_thread_message_queue_send(d->in_thread_queue, &msg, flags);
- av_log(f, AV_LOG_WARNING,
- "Thread message queue blocking; consider raising the "
- "thread_queue_size option (current value: %d)\n",
- d->thread_queue_size);
- }
+ ret = tq_send(d->thread_queue, 0, pkt);
if (ret < 0) {
if (ret != AVERROR_EOF)
av_log(f, AV_LOG_ERROR,
"Unable to send packet to main thread: %s\n",
av_err2str(ret));
- av_packet_free(&msg.pkt);
break;
}
}
finish:
av_assert0(ret < 0);
- av_thread_message_queue_set_err_recv(d->in_thread_queue, ret);
+ tq_send_finish(d->thread_queue, 0);
av_packet_free(&pkt);
@@ -680,16 +645,16 @@ finish:
static void thread_stop(Demuxer *d)
{
InputFile *f = &d->f;
- DemuxMsg msg;
- if (!d->in_thread_queue)
+ if (!d->thread_queue)
return;
- av_thread_message_queue_set_err_send(d->in_thread_queue, AVERROR_EOF);
- while (av_thread_message_queue_recv(d->in_thread_queue, &msg, 0) >= 0)
- av_packet_free(&msg.pkt);
+
+ tq_receive_finish(d->thread_queue, 0);
pthread_join(d->thread, NULL);
- av_thread_message_queue_free(&d->in_thread_queue);
+
+ tq_free(&d->thread_queue);
+
av_thread_message_queue_free(&f->audio_duration_queue);
}
@@ -697,18 +662,20 @@ static int thread_start(Demuxer *d)
{
int ret;
InputFile *f = &d->f;
+ ObjPool *op;
if (d->thread_queue_size <= 0)
d->thread_queue_size = (nb_input_files > 1 ? 8 : 1);
- if (nb_input_files > 1 &&
- (f->ctx->pb ? !f->ctx->pb->seekable :
- strcmp(f->ctx->iformat->name, "lavfi")))
- d->non_blocking = 1;
- ret = av_thread_message_queue_alloc(&d->in_thread_queue,
- d->thread_queue_size, sizeof(DemuxMsg));
- if (ret < 0)
- return ret;
+ op = objpool_alloc_packets();
+ if (!op)
+ return AVERROR(ENOMEM);
+
+ d->thread_queue = tq_alloc(1, d->thread_queue_size, op, pkt_move);
+ if (!d->thread_queue) {
+ objpool_free(&op);
+ return AVERROR(ENOMEM);
+ }
if (d->loop) {
int nb_audio_dec = 0;
@@ -738,31 +705,32 @@ static int thread_start(Demuxer *d)
return 0;
fail:
- av_thread_message_queue_free(&d->in_thread_queue);
+ tq_free(&d->thread_queue);
return ret;
}
-int ifile_get_packet(InputFile *f, AVPacket **pkt)
+int ifile_get_packet(InputFile *f, AVPacket *pkt)
{
Demuxer *d = demuxer_from_ifile(f);
- DemuxMsg msg;
- int ret;
+ int ret, dummy;
- if (!d->in_thread_queue) {
+ if (!d->thread_queue) {
ret = thread_start(d);
if (ret < 0)
return ret;
}
- ret = av_thread_message_queue_recv(d->in_thread_queue, &msg,
- d->non_blocking ?
- AV_THREAD_MESSAGE_NONBLOCK : 0);
+ ret = tq_receive(d->thread_queue, &dummy, pkt);
if (ret < 0)
return ret;
- if (msg.looping)
- return 1;
- *pkt = msg.pkt;
+ if (pkt->opaque) {
+ av_assert0((intptr_t)pkt->opaque == PKT_OPAQUE_SEEK &&
+ !pkt->data && !pkt->side_data_elems);
+ pkt->opaque = NULL;
+ return 1;
+ }
+
return 0;
}
diff --git a/fftools/ffmpeg_filter.c b/fftools/ffmpeg_filter.c
index cfd13dd81a..04c4b4ea7b 100644
--- a/fftools/ffmpeg_filter.c
+++ b/fftools/ffmpeg_filter.c
@@ -2656,7 +2656,7 @@ static int choose_input(const FilterGraph *fg, const FilterGraphThread *fgt)
InputFilterPriv *ifp = ifp_from_ifilter(ifilter);
InputStream *ist = ifp->ist;
- if (input_files[ist->file_index]->eagain || fgt->eof_in[i])
+ if (fgt->eof_in[i])
continue;
nb_requests = av_buffersrc_get_nb_failed_requests(ifp->filter);
--
2.40.1
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