diff options
| -rw-r--r-- | include/linux/cpuset.h | 3 | ||||
| -rw-r--r-- | kernel/cgroup/cpuset.c | 31 | ||||
| -rw-r--r-- | kernel/power/process.c | 2 |
3 files changed, 19 insertions, 17 deletions
diff --git a/include/linux/cpuset.h b/include/linux/cpuset.h index 04c20de66afc..cede4cb98b78 100644 --- a/include/linux/cpuset.h +++ b/include/linux/cpuset.h @@ -54,7 +54,6 @@ 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_read_lock(void); extern void cpuset_read_unlock(void); extern void cpuset_cpus_allowed(struct task_struct *p, struct cpumask *mask); @@ -176,8 +175,6 @@ 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_read_lock(void) { } static inline void cpuset_read_unlock(void) { } diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c index 58f5073acff7..cafd4d2ff882 100644 --- a/kernel/cgroup/cpuset.c +++ b/kernel/cgroup/cpuset.c @@ -3101,7 +3101,7 @@ update_tasks: } /** - * cpuset_hotplug_workfn - handle CPU/memory hotunplug for a cpuset + * cpuset_hotplug - 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 @@ -3116,7 +3116,7 @@ update_tasks: * Note that CPU offlining during suspend is ignored. We don't modify * cpusets across suspend/resume cycles at all. */ -static void cpuset_hotplug_workfn(struct work_struct *work) +static void cpuset_hotplug(bool use_cpu_hp_lock) { static cpumask_t new_cpus; static nodemask_t new_mems; @@ -3201,25 +3201,32 @@ static void cpuset_hotplug_workfn(struct work_struct *work) /* rebuild sched domains if cpus_allowed has changed */ if (cpus_updated || force_rebuild) { force_rebuild = false; - rebuild_sched_domains(); + 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. + */ + percpu_down_write(&cpuset_rwsem); + rebuild_sched_domains_locked(); + percpu_up_write(&cpuset_rwsem); + } } free_cpumasks(NULL, ptmp); } -void cpuset_update_active_cpus(void) +static void cpuset_hotplug_workfn(struct work_struct *work) { - /* - * 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); + cpuset_hotplug(true); } -void cpuset_wait_for_hotplug(void) +void cpuset_update_active_cpus(void) { - flush_work(&cpuset_hotplug_work); + cpuset_hotplug(false); } /* diff --git a/kernel/power/process.c b/kernel/power/process.c index 4b6a54da7e65..08f7019357ee 100644 --- a/kernel/power/process.c +++ b/kernel/power/process.c @@ -204,8 +204,6 @@ void thaw_processes(void) __usermodehelper_set_disable_depth(UMH_FREEZING); thaw_workqueues(); - cpuset_wait_for_hotplug(); - read_lock(&tasklist_lock); for_each_process_thread(g, p) { /* No other threads should have PF_SUSPEND_TASK set */ |