/* Requires cpu_add_remove_lock to be held */
static int _cpu_up(unsigned int cpu, int tasks_frozen)
{
int ret, nr_calls = 0;
void *hcpu = (void *)(long)cpu;
unsigned long mod = tasks_frozen ? CPU_TASKS_FROZEN : 0;
if (cpu_online(cpu) || !cpu_present(cpu))
return -EINVAL;
cpu_hotplug_begin();
ret = __cpu_notify(CPU_UP_PREPARE | mod, hcpu, -1, &nr_calls);
if (ret) {
nr_calls--;
printk(KERN_WARNING "%s: attempt to bring up CPU %u failed\n",
__func__, cpu);
goto out_notify;
}
/* Arch-specific enabling code. */
ret = __cpu_up(cpu);
if (ret != 0)
goto out_notify;
BUG_ON(!cpu_online(cpu));
/* Now call notifier in preparation. */
cpu_notify(CPU_ONLINE | mod, hcpu);
out_notify:
if (ret != 0)
__cpu_notify(CPU_UP_CANCELED | mod, hcpu, nr_calls, NULL);
cpu_hotplug_done();
return ret;
}
/* Requires cpu_add_remove_lock to be held */
static int __cpuinit _cpu_up(unsigned int cpu, int tasks_frozen)
{
int ret, nr_calls = 0;
void *hcpu = (void *)(long)cpu;
unsigned long mod = tasks_frozen ? CPU_TASKS_FROZEN : 0;
struct task_struct *idle;
cpu_hotplug_begin();
if (cpu_online(cpu)) {
ret = 0;
goto out;
}
if (!cpu_present(cpu)) {
ret = -EINVAL;
goto out;
}
idle = idle_thread_get(cpu);
if (IS_ERR(idle)) {
ret = PTR_ERR(idle);
goto out;
}
ret = smpboot_create_threads(cpu);
if (ret)
goto out;
ret = __cpu_notify(CPU_UP_PREPARE | mod, hcpu, -1, &nr_calls);
if (ret) {
nr_calls--;
printk(KERN_WARNING "%s: attempt to bring up CPU %u failed\n",
__func__, cpu);
goto out_notify;
}
/* Arch-specific enabling code. */
ret = __cpu_up(cpu, idle);
if (ret != 0)
goto out_notify;
BUG_ON(!cpu_online(cpu));
/* Wake the per cpu threads */
smpboot_unpark_threads(cpu);
/* Now call notifier in preparation. */
cpu_notify(CPU_ONLINE | mod, hcpu);
out_notify:
if (ret != 0)
__cpu_notify(CPU_UP_CANCELED | mod, hcpu, nr_calls, NULL);
out:
cpu_hotplug_done();
trace_sched_cpu_hotplug(cpu, ret, 1);
return ret;
}
static int bringup_cpu(unsigned int cpu)
{
struct task_struct *idle = idle_thread_get(cpu);
int ret;
/* Arch-specific enabling code. */
ret = __cpu_up(cpu, idle);
if (ret) {
cpu_notify(CPU_UP_CANCELED, cpu);
return ret;
}
ret = bringup_wait_for_ap(cpu);
BUG_ON(!cpu_online(cpu));
return ret;
}
static int __cpuinit _cpu_up(unsigned int cpu, int tasks_frozen)
{
int ret, nr_calls = 0;
void *hcpu = (void *)(long)cpu;
unsigned long mod = tasks_frozen ? CPU_TASKS_FROZEN : 0;
if (cpu_online(cpu) || !cpu_present(cpu))
return -EINVAL;
cpu_hotplug_begin();
ret = __cpu_notify(CPU_UP_PREPARE | mod, hcpu, -1, &nr_calls);
if (ret) {
nr_calls--;
printk(KERN_WARNING "%s: attempt to bring up CPU %u failed\n",
__func__, cpu);
goto out_notify;
}
ret = __cpu_up(cpu);
if (ret != 0)
goto out_notify;
BUG_ON(!cpu_online(cpu));
cpu_notify(CPU_ONLINE | mod, hcpu);
#ifdef CONFIG_HTC_ACPU_DEBUG
{
unsigned int status = 1;
msm_proc_comm(PCOM_BACKUP_CPU_STATUS, (unsigned*)&cpu, (unsigned*) &status);
}
#endif
out_notify:
if (ret != 0)
__cpu_notify(CPU_UP_CANCELED | mod, hcpu, nr_calls, NULL);
cpu_hotplug_done();
return ret;
}
int cpu_up(unsigned int cpu)
{
int notifier_rc, err = 0;
void *hcpu = (void *)(long)cpu;
struct notifier_block *nb = NULL;
if ( !cpu_hotplug_begin() )
return -EBUSY;
if ( (cpu >= NR_CPUS) || cpu_online(cpu) || !cpu_present(cpu) )
{
cpu_hotplug_done();
return -EINVAL;
}
notifier_rc = notifier_call_chain(&cpu_chain, CPU_UP_PREPARE, hcpu, &nb);
if ( notifier_rc != NOTIFY_DONE )
{
err = notifier_to_errno(notifier_rc);
goto fail;
}
err = __cpu_up(cpu);
if ( err < 0 )
goto fail;
notifier_rc = notifier_call_chain(&cpu_chain, CPU_ONLINE, hcpu, NULL);
BUG_ON(notifier_rc != NOTIFY_DONE);
send_guest_global_virq(dom0, VIRQ_PCPU_STATE);
cpu_hotplug_done();
return 0;
fail:
notifier_rc = notifier_call_chain(&cpu_chain, CPU_UP_CANCELED, hcpu, &nb);
BUG_ON(notifier_rc != NOTIFY_DONE);
cpu_hotplug_done();
return err;
}