static int ne_check_cpu_in_cpu_pool()

in drivers/virt/nitro_enclaves/ne_misc_dev.c [736:776]

• 23 lines of code
• 5 McCabe index (conditional complexity)

static int ne_check_cpu_in_cpu_pool(struct ne_enclave *ne_enclave, u32 vcpu_id)
{
	int core_id = -1;
	unsigned int i = 0;
	int rc = -EINVAL;

	if (ne_donated_cpu(ne_enclave, vcpu_id)) {
		dev_err_ratelimited(ne_misc_dev.this_device,
				    "CPU %d already used\n", vcpu_id);

		return -NE_ERR_VCPU_ALREADY_USED;
	}

	/*
	 * If previously allocated a thread of a core to this enclave, but not
	 * the full core, first check remaining sibling(s).
	 */
	for (i = 0; i < ne_enclave->nr_parent_vm_cores; i++)
		if (cpumask_test_cpu(vcpu_id, ne_enclave->threads_per_core[i]))
			return 0;

	mutex_lock(&ne_cpu_pool.mutex);

	/*
	 * If no remaining siblings, get from the NE CPU pool the core
	 * associated with the vCPU and keep track of all the threads in the
	 * enclave threads per core data structure.
	 */
	core_id = ne_get_vcpu_core_from_cpu_pool(vcpu_id);

	rc = ne_set_enclave_threads_per_core(ne_enclave, core_id, vcpu_id);
	if (rc < 0)
		goto unlock_mutex;

	rc = 0;

unlock_mutex:
	mutex_unlock(&ne_cpu_pool.mutex);

	return rc;
}