static ncclResult_t register_mr_buffers()

in src/nccl_ofi_net.c [410:464]

• 42 lines of code
• 8 McCabe index (conditional complexity)

static ncclResult_t register_mr_buffers(ofiComm_t *comm, void *data,
					int size, int type,
					struct fid_mr **mr_handle)
{
	ncclResult_t ret = ncclSuccess;
	int rc;
	struct fi_mr_attr mr_attr = {0};
	struct iovec iov = {0};

	/* Check if provider requires registration of local buffers */
	if ((local_mr != true) && (type == NCCL_PTR_HOST)) {
		NCCL_OFI_TRACE(NCCL_INIT | NCCL_NET,
			"Skip registering host buffer. local_mr: %d", local_mr);
		goto exit;
	}

	/* Check if provider requires registration of cuda device buffers */
	if ((hmem_mr != true) && (type == NCCL_PTR_CUDA)) {
		NCCL_OFI_TRACE(NCCL_INIT | NCCL_NET,
			"Skip registering CUDA buffer. hmem_mr: %d", hmem_mr);
		goto exit;
	}

	/* Populate IOV vector for memory registration */
	iov.iov_base = data;
	iov.iov_len = size;

	/* Initialize MR attributes */
	mr_attr.mr_iov = &iov;
	mr_attr.iov_count = 1;
	mr_attr.access = FI_SEND | FI_RECV;

	if (type == NCCL_PTR_HOST) {
		mr_attr.iface = FI_HMEM_SYSTEM;
	} else {
		mr_attr.iface = FI_HMEM_CUDA;

		/* Get CUDA device ID */
		ret = get_cuda_device(data, &mr_attr.device.cuda);
		if (OFI_UNLIKELY(ret != ncclSuccess)) {
			goto exit;
		}
	}

	rc = fi_mr_regattr(nccl_ofi_component[comm->dev]->domain,
			    &mr_attr, 0, mr_handle);
	if (OFI_UNLIKELY(rc != 0)) {
		NCCL_OFI_WARN("Unable to register memory (type = %d) for device %d. RC: %d, Error: %s",
			       type, comm->dev, rc, fi_strerror(-rc));
		ret = ncclSystemError;
	}

exit:
	return ret;
}