/*
* Ensure that the control task does not run on the to be offlined
* CPU to prevent a deadlock against cfs_b->period_timer.
+ * Also keep at least one housekeeping cpu onlined to avoid generating
+ * an empty sched_domain span.
*/
- cpu = cpumask_any_but(cpu_online_mask, cpu);
- if (cpu >= nr_cpu_ids)
- return -EBUSY;
- return work_on_cpu(cpu, __cpu_down_maps_locked, &work);
+ for_each_cpu_and(cpu, cpu_online_mask, housekeeping_cpumask(HK_TYPE_DOMAIN)) {
+ if (cpu != work.cpu)
+ return work_on_cpu(cpu, __cpu_down_maps_locked, &work);
+ }
+ return -EBUSY;
}
static int cpu_down(unsigned int cpu, enum cpuhp_state target)
[CPUHP_HRTIMERS_PREPARE] = {
.name = "hrtimers:prepare",
.startup.single = hrtimers_prepare_cpu,
- .teardown.single = hrtimers_dead_cpu,
+ .teardown.single = NULL,
},
[CPUHP_SMPCFD_PREPARE] = {
.name = "smpcfd:prepare",
.startup.single = NULL,
.teardown.single = smpcfd_dying_cpu,
},
+ [CPUHP_AP_HRTIMERS_DYING] = {
+ .name = "hrtimers:dying",
+ .startup.single = NULL,
+ .teardown.single = hrtimers_cpu_dying,
+ },
+
/* Entry state on starting. Interrupts enabled from here on. Transient
* state for synchronsization */
[CPUHP_AP_ONLINE] = {