__mock_fence
f1 = __mock_fence(ctx[1], 1);
f2 = __mock_fence(ctx[1], 2);
f3 = __mock_fence(ctx[0], 1);
return __mock_fence(dma_fence_context_alloc(1), 1);
f1 = __mock_fence(ctx[0], 2);
f2 = __mock_fence(ctx[1], 1);
f3 = __mock_fence(ctx[0], 1);
f4 = __mock_fence(ctx[1], 2);