diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/cpu.c | 37 |
1 files changed, 19 insertions, 18 deletions
diff --git a/kernel/cpu.c b/kernel/cpu.c index b03a32595cfe..ab860453841d 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -271,11 +271,25 @@ void cpu_hotplug_enable(void) EXPORT_SYMBOL_GPL(cpu_hotplug_enable); #endif /* CONFIG_HOTPLUG_CPU */ +static void __cpuhp_kick_ap_work(struct cpuhp_cpu_state *st); + static int bringup_wait_for_ap(unsigned int cpu) { struct cpuhp_cpu_state *st = per_cpu_ptr(&cpuhp_state, cpu); + /* Wait for the CPU to reach CPUHP_AP_ONLINE_IDLE */ wait_for_completion(&st->done); + BUG_ON(!cpu_online(cpu)); + + /* Unpark the stopper thread and the hotplug thread of the target cpu */ + stop_machine_unpark(cpu); + kthread_unpark(st->thread); + + /* Should we go further up ? */ + if (st->target > CPUHP_AP_ONLINE_IDLE) { + __cpuhp_kick_ap_work(st); + wait_for_completion(&st->done); + } return st->result; } @@ -296,9 +310,7 @@ static int bringup_cpu(unsigned int cpu) irq_unlock_sparse(); if (ret) return ret; - ret = bringup_wait_for_ap(cpu); - BUG_ON(!cpu_online(cpu)); - return ret; + return bringup_wait_for_ap(cpu); } /* @@ -767,31 +779,20 @@ void notify_cpu_starting(unsigned int cpu) } /* - * Called from the idle task. We need to set active here, so we can kick off - * the stopper thread and unpark the smpboot threads. If the target state is - * beyond CPUHP_AP_ONLINE_IDLE we kick cpuhp thread and let it bring up the - * cpu further. + * Called from the idle task. Wake up the controlling task which brings the + * stopper and the hotplug thread of the upcoming CPU up and then delegates + * the rest of the online bringup to the hotplug thread. */ void cpuhp_online_idle(enum cpuhp_state state) { struct cpuhp_cpu_state *st = this_cpu_ptr(&cpuhp_state); - unsigned int cpu = smp_processor_id(); /* Happens for the boot cpu */ if (state != CPUHP_AP_ONLINE_IDLE) return; st->state = CPUHP_AP_ONLINE_IDLE; - - /* Unpark the stopper thread and the hotplug thread of this cpu */ - stop_machine_unpark(cpu); - kthread_unpark(st->thread); - - /* Should we go further up ? */ - if (st->target > CPUHP_AP_ONLINE_IDLE) - __cpuhp_kick_ap_work(st); - else - complete(&st->done); + complete(&st->done); } /* Requires cpu_add_remove_lock to be held */ |