[FFmpeg-cvslog] libstagefright: avoid potential deadlock on output MediaBuffer
Mohamed Naufal
git at videolan.org
Thu Apr 19 02:17:06 CEST 2012
ffmpeg | branch: master | Mohamed Naufal <naufal22 at gmail.com> | Thu Apr 19 01:26:50 2012 +0530| [1d48e88d4148a271ac56de706265e863e53da94b] | committer: Mohamed Naufal
libstagefright: avoid potential deadlock on output MediaBuffer
Maintain an output queue of AVFrames instead of MediaBuffers
so that the latter can be released early. This avoids a potential deadlock
between the stagefright decoder::read() and Stagefright_decode_frame()
> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=1d48e88d4148a271ac56de706265e863e53da94b
---
libavcodec/libstagefright.cpp | 159 ++++++++++++++++++++++-------------------
1 files changed, 86 insertions(+), 73 deletions(-)
diff --git a/libavcodec/libstagefright.cpp b/libavcodec/libstagefright.cpp
index f373a10..9206170 100644
--- a/libavcodec/libstagefright.cpp
+++ b/libavcodec/libstagefright.cpp
@@ -48,8 +48,7 @@ struct Frame {
int64_t time;
int key;
uint8_t *buffer;
- MediaBuffer* mbuffer;
- int32_t w, h;
+ AVFrame *vframe;
};
struct TimeStamp {
@@ -74,7 +73,7 @@ struct StagefrightContext {
bool source_done;
volatile sig_atomic_t thread_started, thread_exited, stop_decode;
- AVFrame ret_frame;
+ AVFrame *prev_frame;
std::map<int64_t, TimeStamp> *ts_map;
int64_t frame_index;
@@ -156,7 +155,13 @@ void* decode_thread(void *arg)
StagefrightContext *s = (StagefrightContext*)avctx->priv_data;
Frame* frame;
MediaBuffer *buffer;
+ int32_t w, h;
int decode_done = 0;
+ int ret;
+ int src_linesize[3];
+ const uint8_t *src_data[3];
+ int64_t out_frame_index = 0;
+
do {
buffer = NULL;
frame = (Frame*)av_mallocz(sizeof(Frame));
@@ -165,14 +170,63 @@ void* decode_thread(void *arg)
frame->status = AVERROR(ENOMEM);
decode_done = 1;
s->end_frame = NULL;
- } else {
- frame->status = (*s->decoder)->read(&buffer);
- if (frame->status == OK) {
- sp<MetaData> outFormat = (*s->decoder)->getFormat();
- outFormat->findInt32(kKeyWidth , &frame->w);
- outFormat->findInt32(kKeyHeight, &frame->h);
- frame->size = buffer->range_length();
- frame->mbuffer = buffer;
+ goto push_frame;
+ }
+ frame->status = (*s->decoder)->read(&buffer);
+ if (frame->status == OK) {
+ sp<MetaData> outFormat = (*s->decoder)->getFormat();
+ outFormat->findInt32(kKeyWidth , &w);
+ outFormat->findInt32(kKeyHeight, &h);
+ frame->vframe = (AVFrame*)av_mallocz(sizeof(AVFrame));
+ if (!frame->vframe) {
+ frame->status = AVERROR(ENOMEM);
+ decode_done = 1;
+ buffer->release();
+ goto push_frame;
+ }
+ ret = avctx->get_buffer(avctx, frame->vframe);
+ if (ret < 0) {
+ av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
+ frame->status = ret;
+ decode_done = 1;
+ buffer->release();
+ goto push_frame;
+ }
+
+ // The OMX.SEC decoder doesn't signal the modified width/height
+ if (s->decoder_component && !strncmp(s->decoder_component, "OMX.SEC", 7) &&
+ (w & 15 || h & 15)) {
+ if (((w + 15)&~15) * ((h + 15)&~15) * 3/2 == buffer->range_length()) {
+ w = (w + 15)&~15;
+ h = (h + 15)&~15;
+ }
+ }
+
+ if (!avctx->width || !avctx->height || avctx->width > w || avctx->height > h) {
+ avctx->width = w;
+ avctx->height = h;
+ }
+
+ src_linesize[0] = w;
+ if (avctx->pix_fmt == PIX_FMT_YUV420P)
+ src_linesize[1] = src_linesize[2] = w/2;
+ else if (avctx->pix_fmt == PIX_FMT_NV21)
+ src_linesize[1] = w;
+
+ src_data[0] = (uint8_t*)buffer->data();
+ src_data[1] = src_data[0] + src_linesize[0] * h;
+ src_data[2] = src_data[1] + src_linesize[1] * h/2;
+ av_image_copy(frame->vframe->data, frame->vframe->linesize,
+ src_data, src_linesize,
+ avctx->pix_fmt, avctx->width, avctx->height);
+
+ buffer->meta_data()->findInt64(kKeyTime, &out_frame_index);
+ if (out_frame_index && s->ts_map->count(out_frame_index) > 0) {
+ frame->vframe->pts = (*s->ts_map)[out_frame_index].pts;
+ frame->vframe->reordered_opaque = (*s->ts_map)[out_frame_index].reordered_opaque;
+ s->ts_map->erase(out_frame_index);
+ }
+ buffer->release();
} else if (frame->status == INFO_FORMAT_CHANGED) {
if (buffer)
buffer->release();
@@ -181,7 +235,7 @@ void* decode_thread(void *arg)
} else {
decode_done = 1;
}
- }
+push_frame:
while (true) {
pthread_mutex_lock(&s->out_mutex);
if (s->out_queue->size() >= 10) {
@@ -301,17 +355,10 @@ static int Stagefright_decode_frame(AVCodecContext *avctx, void *data,
{
StagefrightContext *s = (StagefrightContext*)avctx->priv_data;
Frame *frame;
- MediaBuffer *mbuffer;
status_t status;
- size_t size;
- uint8_t *buf;
- const uint8_t *src_data[3];
- int w, h;
- int src_linesize[3];
int orig_size = avpkt->size;
AVPacket pkt = *avpkt;
- int64_t out_frame_index = 0;
- int ret;
+ AVFrame *ret_frame;
if (!s->thread_started) {
pthread_create(&s->decode_thread_id, NULL, &decode_thread, avctx);
@@ -392,11 +439,8 @@ static int Stagefright_decode_frame(AVCodecContext *avctx, void *data,
s->out_queue->erase(s->out_queue->begin());
pthread_mutex_unlock(&s->out_mutex);
- mbuffer = frame->mbuffer;
+ ret_frame = frame->vframe;
status = frame->status;
- size = frame->size;
- w = frame->w;
- h = frame->h;
av_freep(&frame);
if (status == ERROR_END_OF_STREAM)
@@ -408,52 +452,15 @@ static int Stagefright_decode_frame(AVCodecContext *avctx, void *data,
return -1;
}
- // The OMX.SEC decoder doesn't signal the modified width/height
- if (s->decoder_component && !strncmp(s->decoder_component, "OMX.SEC", 7) &&
- (w & 15 || h & 15)) {
- if (((w + 15)&~15) * ((h + 15)&~15) * 3/2 == size) {
- w = (w + 15)&~15;
- h = (h + 15)&~15;
- }
- }
-
- if (!avctx->width || !avctx->height || avctx->width > w || avctx->height > h) {
- avctx->width = w;
- avctx->height = h;
- }
-
- ret = avctx->reget_buffer(avctx, &s->ret_frame);
- if (ret < 0) {
- av_log(avctx, AV_LOG_ERROR, "reget buffer() failed\n");
- goto end;
+ if (s->prev_frame) {
+ avctx->release_buffer(avctx, s->prev_frame);
+ av_freep(&s->prev_frame);
}
+ s->prev_frame = ret_frame;
- src_linesize[0] = w;
- if (avctx->pix_fmt == PIX_FMT_YUV420P)
- src_linesize[1] = src_linesize[2] = w/2;
- else if (avctx->pix_fmt == PIX_FMT_NV21)
- src_linesize[1] = w;
-
- buf = (uint8_t*)mbuffer->data();
- src_data[0] = buf;
- src_data[1] = buf + src_linesize[0] * h;
- src_data[2] = src_data[1] + src_linesize[1] * h/2;
- av_image_copy(s->ret_frame.data, s->ret_frame.linesize,
- src_data, src_linesize,
- avctx->pix_fmt, avctx->width, avctx->height);
-
- mbuffer->meta_data()->findInt64(kKeyTime, &out_frame_index);
- if (out_frame_index && s->ts_map->count(out_frame_index) > 0) {
- s->ret_frame.pts = (*s->ts_map)[out_frame_index].pts;
- s->ret_frame.reordered_opaque = (*s->ts_map)[out_frame_index].reordered_opaque;
- s->ts_map->erase(out_frame_index);
- }
*data_size = sizeof(AVFrame);
- *(AVFrame*)data = s->ret_frame;
- ret = orig_size;
-end:
- mbuffer->release();
- return ret;
+ *(AVFrame*)data = *ret_frame;
+ return orig_size;
}
static av_cold int Stagefright_close(AVCodecContext *avctx)
@@ -470,8 +477,10 @@ static av_cold int Stagefright_close(AVCodecContext *avctx)
while (!s->out_queue->empty()) {
frame = *s->out_queue->begin();
s->out_queue->erase(s->out_queue->begin());
- if (frame->size)
- frame->mbuffer->release();
+ if (frame->vframe) {
+ avctx->release_buffer(avctx, frame->vframe);
+ av_freep(&frame->vframe);
+ }
av_freep(&frame);
}
pthread_mutex_unlock(&s->out_mutex);
@@ -501,8 +510,10 @@ static av_cold int Stagefright_close(AVCodecContext *avctx)
pthread_join(s->decode_thread_id, NULL);
- if (s->ret_frame.data[0])
- avctx->release_buffer(avctx, &s->ret_frame);
+ if (s->prev_frame) {
+ avctx->release_buffer(avctx, s->prev_frame);
+ av_freep(&s->prev_frame);
+ }
s->thread_started = false;
}
@@ -518,8 +529,10 @@ static av_cold int Stagefright_close(AVCodecContext *avctx)
while (!s->out_queue->empty()) {
frame = *s->out_queue->begin();
s->out_queue->erase(s->out_queue->begin());
- if (frame->size)
- frame->mbuffer->release();
+ if (frame->vframe) {
+ avctx->release_buffer(avctx, frame->vframe);
+ av_freep(&frame->vframe);
+ }
av_freep(&frame);
}
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