Fixes tsan warnings in fate-apng:
WARNING: ThreadSanitizer: data race (pid=51230)
Read of size 4 at 0x7d50000042fc by main thread (mutexes: write M1000):
#0 frame_copy_props frame.c:302 (ffmpeg:x86_64+0x1019a35d6)
[..]
Previous write of size 4 at 0x7d50000042fc by thread T1 (mutexes: write M997):
#0 decode_idat_chunk pngdec.c:708 (ffmpeg:x86_64+0x100f5562a)
Fixes a reported (but false) race condition in tsan for fate-apng:
WARNING: ThreadSanitizer: data race (pid=6274)
Read of size 4 at 0x7d680001ec78 by main thread (mutexes: write M1338):
#0 update_thread_context src/libavcodec/pngdec.c:1456 (ffmpeg+0x000000dacf0c)
[..]
Previous write of size 4 at 0x7d680001ec78 by thread T1 (mutexes: write M1335):
#0 decode_idat_chunk src/libavcodec/pngdec.c:737 (ffmpeg+0x000000dae951)
Values from subsequent values are guaranteed to be identical (since
poc and nal_unit_type are checked to be the same between slices), so
this doesn't affect output in any way, but does resolve the remaining
reported race conditions (by tsan) in fate-hevc.
In practice, this fixes tsan warnings like this:
WARNING: ThreadSanitizer: data race (pid=25334)
Read of size 4 at 0x7d9c0001adcc by main thread (mutexes: write M1386):
#0 hevc_update_thread_context src/libavcodec/hevcdec.c:3310 (ffmpeg+0x000000b41c7c)
[..]
Previous write of size 4 at 0x7d9c0001adcc by thread T1 (mutexes: write M1383):
#0 hls_slice_header src/libavcodec/hevcdec.c:596 (ffmpeg+0x000000b43a22)
Otherwise the thread may still be in the middle of decoding a previous
frame, which would effectively trigger a race condition on any field
concurrently read and written.
In practice, this fixes tsan warnings like the following:
WARNING: ThreadSanitizer: data race (pid=17380)
Write of size 4 at 0x7d64000160fc by main thread:
#0 update_context_from_user src/libavcodec/pthread_frame.c:335 (ffmpeg+0x000000dca515)
[..]
Previous read of size 4 at 0x7d64000160fc by thread T2 (mutexes: write M1821):
#0 ff_thread_report_progress src/libavcodec/pthread_frame.c:565 (ffmpeg+0x000000dcb08a)
Fixes tsan warnings in several audio codecs (flac, alac, wavpack, tta
and tak) that look like this:
WARNING: ThreadSanitizer: data race (pid=14340)
Read of size 4 at 0x7d64000169d8 by main thread (mutexes: write M1335):
#0 update_context_from_thread src/libavcodec/pthread_frame.c:284 (ffmpeg+0x000000dc795f)
[..]
Previous write of size 4 at 0x7d64000169d8 by thread T1 (mutexes: write M1333):
#0 wavpack_decode_block src/libavcodec/wavpack.c:1012 (ffmpeg+0x00000112b175)
This is how the ref list manager links bitstream IDs to H264Picture/Ref
objects, and is local to the producer thread. There is no need for the
consumer thread to know the bitstream IDs of its references in their
respective producer threads.
In practice, this fixes tsan warnings when running fate-h264:
WARNING: ThreadSanitizer: data race (pid=19295)
Read of size 4 at 0x7dbc0000e614 by main thread (mutexes: write M1914):
#0 ff_h264_ref_picture src/libavcodec/h264_picture.c:112 (ffmpeg+0x0000013b3709)
[..]
Previous write of size 4 at 0x7dbc0000e614 by thread T2 (mutexes: write M1917):
#0 build_def_list src/libavcodec/h264_refs.c:91 (ffmpeg+0x0000013b46cf)
The value must be identical between slices, since mbaff depends on
picture_structure and sps, both of which are checked to be identical
to the first slice before this point.
In practice, this silences some tsan warnings in fate-h264.
This fixes race conditions reported by tsan in fate-lagarith. The races
were because each thread's LagarithContext::avctx was set to the first
thread's AVCodecContext.
Otherwise all thread's private contexts have the avctx pointer set to
the AVCodecContext of the first thread, which means all writes to
ctx->avctx->* (in e.g. read_header) are effectively race conditions.
Fixes fate-dnxhd under tsan.
Fixes CID1401671
Reviewed-by: Paul B Mahol <onemda@gmail.com>
Reviewed-by: Nicolas George <george@nsup.org>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Get rid of the "ret" variable, and always use err. Report the packet as
consumed if err is unset. This should be equivalent to the old code,
which obviously required err=0 for p->result>=0 (and otherwise,
p->result must have had the value err was last set to). The code block
added by commit 32a5b63126 is also not needed anymore, because the new
code strictly returns err if it's >=0.
Reviewed-by: "Ronald S. Bultje" <rsbultje@gmail.com>
Intra-only codecs should either be able to read these items from the
bitstream, or they should be set upon codec initialization. In both
cases, syncing these items at runtime is unnecessary.
In practice, this fixes race conditions for decoders that read these
values from the bitstream.
Clément Bœsch
Matthieu Bouron
James Almer
Ronald S. Bultje
Martin Vignali
Jun Zhao
Diego Biurrun
Michael Niedermayer
Paul B Mahol
Dzung Hoang
Takayuki 'January June' Suwa
Mark Thompson
Clément Bœsch
wm4