+static int dlpar_offline_cpu(struct device_node *dn)
+{
+ int rc = 0;
+ unsigned int cpu;
+ int len, nthreads, i;
+ const __be32 *intserv;
+ u32 thread;
+
+ intserv = of_get_property(dn, "ibm,ppc-interrupt-server#s", &len);
+ if (!intserv)
+ return -EINVAL;
+
+ nthreads = len / sizeof(u32);
+
+ cpu_maps_update_begin();
+ for (i = 0; i < nthreads; i++) {
+ thread = be32_to_cpu(intserv[i]);
+ for_each_present_cpu(cpu) {
+ if (get_hard_smp_processor_id(cpu) != thread)
+ continue;
+
+ if (get_cpu_current_state(cpu) == CPU_STATE_OFFLINE)
+ break;
+
+ if (get_cpu_current_state(cpu) == CPU_STATE_ONLINE) {
+ set_preferred_offline_state(cpu,
+ CPU_STATE_OFFLINE);
+ cpu_maps_update_done();
+ timed_topology_update(1);
+ rc = device_offline(get_cpu_device(cpu));
+ if (rc)
+ goto out;
+ cpu_maps_update_begin();
+ break;
+ }
+
+ /*
+ * The cpu is in CPU_STATE_INACTIVE.
+ * Upgrade it's state to CPU_STATE_OFFLINE.
+ */
+ set_preferred_offline_state(cpu, CPU_STATE_OFFLINE);
+ WARN_ON(plpar_hcall_norets(H_PROD, thread) != H_SUCCESS);
+ __cpu_die(cpu);
+ break;
+ }
+ if (cpu == num_possible_cpus()) {
+ pr_warn("Could not find cpu to offline with physical id 0x%x\n",
+ thread);
+ }
+ }
+ cpu_maps_update_done();
+
+out:
+ return rc;
+}
+