This tries to handle cases where separate invocations of decode_frame()
(each running in separate threads) write to respective fields in the
same AVFrame->data[]. Having per-field owners makes interaction between
readers (the referencing thread) and writers (the decoding thread)
slightly more optimal if both accesses are field-based, since they will
use the respective producer's thread objects (mutex/cond) instead of
sharing the thread objects of the first field's producer.
In practice, this fixes the following tsan-warning in fate-h264:
WARNING: ThreadSanitizer: data race (pid=21615)
Read of size 4 at 0x7d640000d9fc by thread T2 (mutexes: write M1006):
#0 ff_thread_report_progress pthread_frame.c:569 (ffmpeg:x86_64+0x100f7cf54)
[..]
Previous write of size 4 at 0x7d640000d9fc by main thread (mutexes: write M1004):
#0 update_context_from_user pthread_frame.c:335 (ffmpeg:x86_64+0x100f81abb)
Just like get_buffer, get_format should not be called from a different
thread if thread_safe_callbacks is not set.
Signed-off-by: Reimar Döffinger <Reimar.Doeffinger@gmx.de>
thread_count passed to ff_thread_init() is only used to set AVCodecContext.
thread_count, and can be removed. Instead move it to the legacy implementation
of avcodec_thread_init().
This also fixes the problem that calling avcodec_thread_init() with pthreads
enabled did not set it since ff1efc524c.
Signed-off-by: Janne Grunau <janne-libav@jannau.net>
As a side effect of the last commit, avcodec_open() now calls it automatically,
so there is no longer any need for clients to call it.
Instead they should set AVCodecContext.thread_count.
avcodec_thread_free() is deprecated, and will be removed from avcodec.h at the
next MAJOR libavcodec bump.
Rename the functions to ff_thread_init/free, since they are now internal.
Wrappers are provided to maintain API compatibility.
Signed-off-by: Ronald S. Bultje <rsbultje@gmail.com>
(cherry picked from commit c0b102ca03)
As a side effect of the last commit, avcodec_open() now calls it automatically,
so there is no longer any need for clients to call it.
Instead they should set AVCodecContext.thread_count.
avcodec_thread_free() is deprecated, and will be removed from avcodec.h at the
next MAJOR libavcodec bump.
Rename the functions to ff_thread_init/free, since they are now internal.
Wrappers are provided to maintain API compatibility.
Signed-off-by: Ronald S. Bultje <rsbultje@gmail.com>