extern int cpuset_init(void);
extern void cpuset_init_smp(void);
+extern void cpuset_force_rebuild(void);
extern void cpuset_update_active_cpus(void);
+extern void cpuset_wait_for_hotplug(void);
extern void cpuset_cpus_allowed(struct task_struct *p, struct cpumask *mask);
extern void cpuset_cpus_allowed_fallback(struct task_struct *p);
extern nodemask_t cpuset_mems_allowed(struct task_struct *p);
static inline int cpuset_init(void) { return 0; }
static inline void cpuset_init_smp(void) {}
+static inline void cpuset_force_rebuild(void) { }
+
static inline void cpuset_update_active_cpus(void)
{
partition_sched_domains(1, NULL, NULL);
}
+static inline void cpuset_wait_for_hotplug(void) { }
+
static inline void cpuset_cpus_allowed(struct task_struct *p,
struct cpumask *mask)
{
mutex_unlock(&cpuset_mutex);
}
+static bool force_rebuild;
+
+void cpuset_force_rebuild(void)
+{
+ force_rebuild = true;
+}
+
/**
- * cpuset_hotplug - handle CPU/memory hotunplug for a cpuset
+ * cpuset_hotplug_workfn - handle CPU/memory hotunplug for a cpuset
*
* This function is called after either CPU or memory configuration has
* changed and updates cpuset accordingly. The top_cpuset is always
* Note that CPU offlining during suspend is ignored. We don't modify
* cpusets across suspend/resume cycles at all.
*/
-static void cpuset_hotplug(bool use_cpu_hp_lock)
+static void cpuset_hotplug_workfn(struct work_struct *work)
{
static cpumask_t new_cpus;
static nodemask_t new_mems;
}
/* rebuild sched domains if cpus_allowed has changed */
- if (cpus_updated) {
- if (use_cpu_hp_lock)
- rebuild_sched_domains();
- else {
- /* Acquiring cpu_hotplug_lock is not required.
- * When cpuset_hotplug() is called in hotplug path,
- * cpu_hotplug_lock is held by the hotplug context
- * which is waiting for cpuhp_thread_fun to indicate
- * completion of callback.
- */
- mutex_lock(&cpuset_mutex);
- rebuild_sched_domains_cpuslocked();
- mutex_unlock(&cpuset_mutex);
- }
+ if (cpus_updated || force_rebuild) {
+ force_rebuild = false;
+ rebuild_sched_domains();
}
}
-static void cpuset_hotplug_workfn(struct work_struct *work)
+void cpuset_update_active_cpus(void)
{
- cpuset_hotplug(true);
+ /*
+ * We're inside cpu hotplug critical region which usually nests
+ * inside cgroup synchronization. Bounce actual hotplug processing
+ * to a work item to avoid reverse locking order.
+ */
+ schedule_work(&cpuset_hotplug_work);
}
-void cpuset_update_active_cpus(void)
+void cpuset_wait_for_hotplug(void)
{
- cpuset_hotplug(false);
+ flush_work(&cpuset_hotplug_work);
}
/*