[FFmpeg-cvslog] avfilter/vf_yadif_cuda: Remove unnecessary stream synchronisation

[Philip Langdale]

ffmpeg | branch: master | Philip Langdale <philipl at overt.org> | Sat Mar 30 08:50:44 2019 -0700| [c0b6e4cb6d6d41dbf2684891ed9dd43d9ddfb804] | committer: Philip Langdale

avfilter/vf_yadif_cuda: Remove unnecessary stream synchronisation

I put this call in by habit, rather than because there was any
actual need. The filter is simply processing frames one after
the other and has no need to synchronise.

malakudi on the devtalk forums noticed a slowdown when using nvenc
with temporal/spatial aq and that the slowdown went away if the
sync call was removed. I also verified that in the basic encoding
case there's an observable speedup.

I also verified that we aren't doing unnecessary sync calls in any
other filter.

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=c0b6e4cb6d6d41dbf2684891ed9dd43d9ddfb804
---

 libavfilter/vf_yadif_cuda.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/libavfilter/vf_yadif_cuda.c b/libavfilter/vf_yadif_cuda.c
index 141dcb17f7..c9eb1a229d 100644
--- a/libavfilter/vf_yadif_cuda.c
+++ b/libavfilter/vf_yadif_cuda.c
@@ -180,8 +180,6 @@ static void filter(AVFilterContext *ctx, AVFrame *dst,
                     parity, tff);
     }
 
-    CHECK_CU(cu->cuStreamSynchronize(s->stream));
-
 exit:
     CHECK_CU(cu->cuCtxPopCurrent(&dummy));
     return;