static int nvme_rdma_alloc_io_queues()

in host/rdma.c [720:791]

• 51 lines of code
• 10 McCabe index (conditional complexity)

static int nvme_rdma_alloc_io_queues(struct nvme_rdma_ctrl *ctrl)
{
	struct nvmf_ctrl_options *opts = ctrl->ctrl.opts;
	struct ib_device *ibdev = ctrl->device->dev;
	unsigned int nr_io_queues, nr_default_queues;
	unsigned int nr_read_queues, nr_poll_queues;
	int i, ret;

	nr_read_queues = min_t(unsigned int, ibdev->num_comp_vectors,
				min(opts->nr_io_queues, num_online_cpus()));
	nr_default_queues =  min_t(unsigned int, ibdev->num_comp_vectors,
				min(opts->nr_write_queues, num_online_cpus()));
	nr_poll_queues = min(opts->nr_poll_queues, num_online_cpus());
	nr_io_queues = nr_read_queues + nr_default_queues + nr_poll_queues;

	ret = nvme_set_queue_count(&ctrl->ctrl, &nr_io_queues);
	if (ret)
		return ret;

	if (nr_io_queues == 0) {
		dev_err(ctrl->ctrl.device,
			"unable to set any I/O queues\n");
		return -ENOMEM;
	}

	ctrl->ctrl.queue_count = nr_io_queues + 1;
	dev_info(ctrl->ctrl.device,
		"creating %d I/O queues.\n", nr_io_queues);

	if (opts->nr_write_queues && nr_read_queues < nr_io_queues) {
		/*
		 * separate read/write queues
		 * hand out dedicated default queues only after we have
		 * sufficient read queues.
		 */
		ctrl->io_queues[HCTX_TYPE_READ] = nr_read_queues;
		nr_io_queues -= ctrl->io_queues[HCTX_TYPE_READ];
		ctrl->io_queues[HCTX_TYPE_DEFAULT] =
			min(nr_default_queues, nr_io_queues);
		nr_io_queues -= ctrl->io_queues[HCTX_TYPE_DEFAULT];
	} else {
		/*
		 * shared read/write queues
		 * either no write queues were requested, or we don't have
		 * sufficient queue count to have dedicated default queues.
		 */
		ctrl->io_queues[HCTX_TYPE_DEFAULT] =
			min(nr_read_queues, nr_io_queues);
		nr_io_queues -= ctrl->io_queues[HCTX_TYPE_DEFAULT];
	}

	if (opts->nr_poll_queues && nr_io_queues) {
		/* map dedicated poll queues only if we have queues left */
		ctrl->io_queues[HCTX_TYPE_POLL] =
			min(nr_poll_queues, nr_io_queues);
	}

	for (i = 1; i < ctrl->ctrl.queue_count; i++) {
		ret = nvme_rdma_alloc_queue(ctrl, i,
				ctrl->ctrl.sqsize + 1);
		if (ret)
			goto out_free_queues;
	}

	return 0;

out_free_queues:
	for (i--; i >= 1; i--)
		nvme_rdma_free_queue(&ctrl->queues[i]);

	return ret;
}