Re: [FFmpeg-devel] [PATCH] avformat/aviobuf: realloc memory in ffio_ensure_seekback()
On Tue, Sep 15, 2020 at 01:35:25PM +0200, Paul B Mahol wrote: > This removes big CPU overhead for demuxing chained ogg streams. > > Signed-off-by: Paul B Mahol > --- > libavformat/aviobuf.c | 5 ++--- > 1 file changed, 2 insertions(+), 3 deletions(-) > > diff --git a/libavformat/aviobuf.c b/libavformat/aviobuf.c > index a77517d712..6d01150f66 100644 > --- a/libavformat/aviobuf.c > +++ b/libavformat/aviobuf.c > @@ -1005,12 +1005,11 @@ int ffio_ensure_seekback(AVIOContext *s, int64_t > buf_size) > return 0; > av_assert0(!s->write_flag); > > -buffer = av_malloc(buf_size); > +buffer = s->buffer; > +buffer = av_realloc(buffer, buf_size); > if (!buffer) > return AVERROR(ENOMEM); This would reduce the guranteed alignment. If that is not an issue then this patch could be ok thx [...] -- Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB Many that live deserve death. And some that die deserve life. Can you give it to them? Then do not be too eager to deal out death in judgement. For even the very wise cannot see all ends. -- Gandalf signature.asc Description: PGP signature ___ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-devel] [PATCH] avformat/aviobuf: realloc memory in ffio_ensure_seekback()
On Tue, 15 Sep 2020, Andreas Rheinhardt wrote: Marton Balint: On Tue, 15 Sep 2020, Paul B Mahol wrote: This removes big CPU overhead for demuxing chained ogg streams. Signed-off-by: Paul B Mahol --- libavformat/aviobuf.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/libavformat/aviobuf.c b/libavformat/aviobuf.c index a77517d712..6d01150f66 100644 --- a/libavformat/aviobuf.c +++ b/libavformat/aviobuf.c @@ -1005,12 +1005,11 @@ int ffio_ensure_seekback(AVIOContext *s, int64_t buf_size) return 0; av_assert0(!s->write_flag); - buffer = av_malloc(buf_size); + buffer = s->buffer; + buffer = av_realloc(buffer, buf_size); It is not guaranteed that buffer is allocated with av_realloc, so you cannot realloc it. This isn't true since 21f70940ae106bfffa07e73057cdb4b5e81a767a any more. Then av_realloc() docs need updating as well. Regards, Marton ___ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-devel] [PATCH] avformat/aviobuf: realloc memory in ffio_ensure_seekback()
Marton Balint: > > > On Tue, 15 Sep 2020, Paul B Mahol wrote: > >> This removes big CPU overhead for demuxing chained ogg streams. >> >> Signed-off-by: Paul B Mahol >> --- >> libavformat/aviobuf.c | 5 ++--- >> 1 file changed, 2 insertions(+), 3 deletions(-) >> >> diff --git a/libavformat/aviobuf.c b/libavformat/aviobuf.c >> index a77517d712..6d01150f66 100644 >> --- a/libavformat/aviobuf.c >> +++ b/libavformat/aviobuf.c >> @@ -1005,12 +1005,11 @@ int ffio_ensure_seekback(AVIOContext *s, >> int64_t buf_size) >> return 0; >> av_assert0(!s->write_flag); >> >> - buffer = av_malloc(buf_size); >> + buffer = s->buffer; >> + buffer = av_realloc(buffer, buf_size); > > It is not guaranteed that buffer is allocated with av_realloc, so you > cannot realloc it. > This isn't true since 21f70940ae106bfffa07e73057cdb4b5e81a767a any more. - Andreas ___ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-devel] [PATCH] avformat/aviobuf: realloc memory in ffio_ensure_seekback()
On Tue, 15 Sep 2020, Paul B Mahol wrote: This removes big CPU overhead for demuxing chained ogg streams. Signed-off-by: Paul B Mahol --- libavformat/aviobuf.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/libavformat/aviobuf.c b/libavformat/aviobuf.c index a77517d712..6d01150f66 100644 --- a/libavformat/aviobuf.c +++ b/libavformat/aviobuf.c @@ -1005,12 +1005,11 @@ int ffio_ensure_seekback(AVIOContext *s, int64_t buf_size) return 0; av_assert0(!s->write_flag); -buffer = av_malloc(buf_size); +buffer = s->buffer; +buffer = av_realloc(buffer, buf_size); It is not guaranteed that buffer is allocated with av_realloc, so you cannot realloc it. Regards, Marton if (!buffer) return AVERROR(ENOMEM); -memcpy(buffer, s->buffer, filled); -av_free(s->buffer); s->buf_ptr = buffer + (s->buf_ptr - s->buffer); s->buf_end = buffer + (s->buf_end - s->buffer); s->buffer = buffer; -- 2.17.1 ___ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe". ___ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-devel] [PATCH] avformat/aviobuf: realloc memory in ffio_ensure_seekback()
Paul B Mahol (12020-09-15): > It leaks nothing in case of failure. > In case of failure old memory is kept and > seeking back will fail and thus give errors when syncing. My bad, it was a common pattern, but avoided here. -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-devel] [PATCH] avformat/aviobuf: realloc memory in ffio_ensure_seekback()
On Tue, Sep 15, 2020 at 01:39:45PM +0200, Nicolas George wrote: > Paul B Mahol (12020-09-15): > > This removes big CPU overhead for demuxing chained ogg streams. > > > > Signed-off-by: Paul B Mahol > > --- > > libavformat/aviobuf.c | 5 ++--- > > 1 file changed, 2 insertions(+), 3 deletions(-) > > > > diff --git a/libavformat/aviobuf.c b/libavformat/aviobuf.c > > index a77517d712..6d01150f66 100644 > > --- a/libavformat/aviobuf.c > > +++ b/libavformat/aviobuf.c > > @@ -1005,12 +1005,11 @@ int ffio_ensure_seekback(AVIOContext *s, int64_t > > buf_size) > > return 0; > > av_assert0(!s->write_flag); > > > > -buffer = av_malloc(buf_size); > > +buffer = s->buffer; > > > +buffer = av_realloc(buffer, buf_size); > > if (!buffer) > > return AVERROR(ENOMEM); > > Leaks in case of failure. It leaks nothing in case of failure. In case of failure old memory is kept and seeking back will fail and thus give errors when syncing. > > > > > -memcpy(buffer, s->buffer, filled); > > -av_free(s->buffer); > > s->buf_ptr = buffer + (s->buf_ptr - s->buffer); > > s->buf_end = buffer + (s->buf_end - s->buffer); > > s->buffer = buffer; > > -- > Nicolas George > ___ > ffmpeg-devel mailing list > ffmpeg-devel@ffmpeg.org > https://ffmpeg.org/mailman/listinfo/ffmpeg-devel > > To unsubscribe, visit link above, or email > ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe". ___ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-devel] [PATCH] avformat/aviobuf: realloc memory in ffio_ensure_seekback()
Paul B Mahol (12020-09-15): > This removes big CPU overhead for demuxing chained ogg streams. > > Signed-off-by: Paul B Mahol > --- > libavformat/aviobuf.c | 5 ++--- > 1 file changed, 2 insertions(+), 3 deletions(-) > > diff --git a/libavformat/aviobuf.c b/libavformat/aviobuf.c > index a77517d712..6d01150f66 100644 > --- a/libavformat/aviobuf.c > +++ b/libavformat/aviobuf.c > @@ -1005,12 +1005,11 @@ int ffio_ensure_seekback(AVIOContext *s, int64_t > buf_size) > return 0; > av_assert0(!s->write_flag); > > -buffer = av_malloc(buf_size); > +buffer = s->buffer; > +buffer = av_realloc(buffer, buf_size); > if (!buffer) > return AVERROR(ENOMEM); Leaks in case of failure. > > -memcpy(buffer, s->buffer, filled); > -av_free(s->buffer); > s->buf_ptr = buffer + (s->buf_ptr - s->buffer); > s->buf_end = buffer + (s->buf_end - s->buffer); > s->buffer = buffer; -- Nicolas George signature.asc Description: PGP signature ___ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
[FFmpeg-devel] [PATCH] avformat/aviobuf: realloc memory in ffio_ensure_seekback()
This removes big CPU overhead for demuxing chained ogg streams. Signed-off-by: Paul B Mahol --- libavformat/aviobuf.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/libavformat/aviobuf.c b/libavformat/aviobuf.c index a77517d712..6d01150f66 100644 --- a/libavformat/aviobuf.c +++ b/libavformat/aviobuf.c @@ -1005,12 +1005,11 @@ int ffio_ensure_seekback(AVIOContext *s, int64_t buf_size) return 0; av_assert0(!s->write_flag); -buffer = av_malloc(buf_size); +buffer = s->buffer; +buffer = av_realloc(buffer, buf_size); if (!buffer) return AVERROR(ENOMEM); -memcpy(buffer, s->buffer, filled); -av_free(s->buffer); s->buf_ptr = buffer + (s->buf_ptr - s->buffer); s->buf_end = buffer + (s->buf_end - s->buffer); s->buffer = buffer; -- 2.17.1 ___ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
