hmem/cuda: Add env variable to enable/disable CUDA DMABUF

Enabled by default

Signed-off-by: Chuck Fossen <[email protected]>

Author: Chuck Fossen

src/hmem_cuda.c

@@ -763,6 +763,9 @@ int cuda_hmem_init(void)
 			"If libfabric is not compiled with gdrcopy support, "
 			"this variable is not checked. (default: true)");
 
+	fi_param_define(NULL, "hmem_cuda_use_dmabuf", FI_PARAM_BOOL,
+			"Use dma-buf for sharing buffer with hardware. (default:true)");
+
 	ret = cuda_hmem_dl_init();
 	if (ret != FI_SUCCESS)
 		return ret;
@@ -936,7 +939,11 @@ bool cuda_is_gdrcopy_enabled(void)
 
 bool cuda_is_dmabuf_supported(void)
 {
-	return cuda_attr.dmabuf_supported;
+	int use_dmabuf = 1;
+
+	fi_param_get_bool(NULL, "hmem_cuda_use_dmabuf", &use_dmabuf);
+
+	return use_dmabuf && cuda_attr.dmabuf_supported;
 }
 
 #else