avutil/hcontext_cuda: Remove unnecessary stream synchronisation

Similarly to the previous changes, we don't need to synchronise
after a memcpy to device memory. On the other hand, we need to
keep synchronising after a copy to host memory, otherwise there's
no guarantee that subsequent host reads will return valid data.

diff --git a/libavutil/hwcontext_cuda.c b/libavutil/hwcontext_cuda.c
index 540a7610ef954dd94302a7150b0fea541b61fad5..cca39e9fc753f9442fecc3c02af45e9bf10fa240 100644 (file)
--- a/libavutil/hwcontext_cuda.c
+++ b/libavutil/hwcontext_cuda.c
@@ -268,10 +268,6 @@ static int cuda_transfer_data_to(AVHWFramesContext *ctx, AVFrame *dst,
             goto exit;
     }
 
-    ret = CHECK_CU(cu->cuStreamSynchronize(hwctx->stream));
-    if (ret < 0)
-        goto exit;
-
 exit:
     CHECK_CU(cu->cuCtxPopCurrent(&dummy));