Moved location of decoder destroy to prevent threading issues.

Moved the location of the cuvidDestroyDecoder call to the end of the resolve thread, to attempt to prevent multiple threads destroying it simultaneously.

Author: elFarto

src/vabackend.c

@@ -331,18 +331,9 @@ static bool destroyContext(NVDriver *drv, NVContext *nvCtx) {
     freeBuffer(&nvCtx->sliceOffsets);
     freeBuffer(&nvCtx->bitstreamBuffer);
 
-    bool successful = true;
-    if (nvCtx->decoder != NULL) {
-      CUresult result = cv->cuvidDestroyDecoder(nvCtx->decoder);
-      if (result != CUDA_SUCCESS) {
-          LOG("cuvidDestroyDecoder failed: %d", result);
-          successful = false;
-      }
-    }
-    nvCtx->decoder = NULL;
     CHECK_CUDA_RESULT_RETURN(cu->cuCtxPopCurrent(NULL), false);
 
-    return successful;
+    return true;
 }
 
 static void deleteAllObjects(NVDriver *drv) {
@@ -455,6 +446,15 @@ static void* resolveSurfaces(void *param) {
         CHECK_CUDA_RESULT(cv->cuvidUnmapVideoFrame(ctx->decoder, deviceMemory));
     }
 out:
+    //release the decoder here to prevent multiple threads attempting it
+    if (ctx->decoder != NULL) {
+        CUresult result = cv->cuvidDestroyDecoder(ctx->decoder);
+        ctx->decoder = NULL;
+        if (result != CUDA_SUCCESS) {
+            LOG("cuvidDestroyDecoder failed: %d", result);
+        }
+    }
+
     LOG("[RT] Resolve thread for %p exiting", ctx);
     return NULL;
 }

src/vabackend.h

@@ -176,7 +176,7 @@ typedef struct _NVContext
     NVSurface*          surfaceQueue[SURFACE_QUEUE_SIZE];
     int                 surfaceQueueReadIdx;
     int                 surfaceQueueWriteIdx;
-    bool                exiting;
+    volatile bool       exiting;
     pthread_mutex_t     surfaceCreationMutex;
     int                 surfaceCount;
 } NVContext;