[FFmpeg-devel] [PATCH] Fix threaded mpeg*video encoding

[Michael Niedermayer]

On Thu, Jul 01, 2010 at 03:48:23PM +0100, M?ns Rullg?rd wrote:
> M?ns Rullg?rd <mans at mansr.com> writes:
> 
> > Michael Niedermayer <michaelni at gmx.at> writes:
> >
> >> On Thu, Jul 01, 2010 at 12:26:25PM +0100, M?ns Rullg?rd wrote:
> >>> Michael Niedermayer <michaelni at gmx.at> writes:
> >>> 
> >>> > On Thu, Jul 01, 2010 at 04:01:24AM +0100, M?ns Rullg?rd wrote:
> >>> >> Michael Niedermayer <michaelni at gmx.at> writes:
> >>> >> 
> >>> >> > On Wed, Jun 30, 2010 at 03:49:34PM +0100, Mans Rullgard wrote:
> >>> >> >> This allocates per-thread copies of some buffers which are updated
> >>> >> >> concurrently from the encoding threads.
> >>> >> >
> >>> >> > is this fixing a bug?
> >>> >> > if so please elaborate what and where. My guess would be toward
> >>> >> > ac_val being the one causing the issues.
> >>> >> 
> >>> >> The threaded regression tests are failing randomly with pthreads enabled:
> >>> >> 
> >>> >> http://fate.multimedia.cx/index.php?test_result=66882641
> >>> >> http://fate.multimedia.cx/index.php?test_result=66852547
> >>> >> http://fate.multimedia.cx/index.php?test_result=66876769
> >>> >> 
> >>> >> Those are just a few examples.  Valgrind complained about most of
> >>> >> those buffers, particularly ac_val and dc_val, and I add a couple
> >>> >> since they were written close to the places valgrind identified.  Race
> >>> >> detection is never exact.
> >>> >
> >>> > could you try to just change ac_val and see if this makes the issue
> >>> > go away?
> >>> > for ac_val i found ff_mpeg4_clean_buffers() as possible reason for the
> >>> > race, for the others i am not aware of code that can lead to a race
> >>> 
> >>> So OK to commit just the ac_val parts and see what happens?
> >>
> >> ok
> >
> > Done.  Let's keep an eye on FATE.
> 
> We still have some failures:
> 
> http://fate.multimedia.cx/index.php?build_record=251859
> http://fate.multimedia.cx/index.php?build_record=251951
> http://fate.multimedia.cx/index.php?build_record=251969

have you confirmed that your whole patch is fixining them?
cbp_table and pred_dir_table seem decoder only
coded_block stuff seems msmpeg4

[...]

-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

The real ebay dictionary, page 1
"Used only once"    - "Some unspecified defect prevented a second use"
"In good condition" - "Can be repaird by experienced expert"
"As is" - "You wouldnt want it even if you were payed for it, if you knew ..."
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 189 bytes
Desc: Digital signature
URL: <http://lists.mplayerhq.hu/pipermail/ffmpeg-devel/attachments/20100701/353e752d/attachment.pgp>