diff options
Diffstat (limited to 'kernel/kthread.c')
| -rw-r--r-- | kernel/kthread.c | 30 |
1 files changed, 29 insertions, 1 deletions
diff --git a/kernel/kthread.c b/kernel/kthread.c index 5942eeafb9ac..62a9f5534712 100644 --- a/kernel/kthread.c +++ b/kernel/kthread.c @@ -431,6 +431,34 @@ void kthread_bind(struct task_struct *p, unsigned int cpu) } EXPORT_SYMBOL(kthread_bind); +#if defined(CONFIG_SCHED_MUQSS) && defined(CONFIG_SMP) +extern void __do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask); + +/* + * new_kthread_bind is a special variant of __kthread_bind_mask. + * For new threads to work on muqss we want to call do_set_cpus_allowed + * without the task_cpu being set and the task rescheduled until they're + * rescheduled on their own so we call __do_set_cpus_allowed directly which + * only changes the cpumask. This is particularly important for smpboot threads + * to work. + */ +static void new_kthread_bind(struct task_struct *p, unsigned int cpu) +{ + unsigned long flags; + + if (WARN_ON(!wait_task_inactive(p, TASK_UNINTERRUPTIBLE))) + return; + + /* It's safe because the task is inactive. */ + raw_spin_lock_irqsave(&p->pi_lock, flags); + __do_set_cpus_allowed(p, cpumask_of(cpu)); + p->flags |= PF_NO_SETAFFINITY; + raw_spin_unlock_irqrestore(&p->pi_lock, flags); +} +#else +#define new_kthread_bind(p, cpu) kthread_bind(p, cpu) +#endif + /** * kthread_create_on_cpu - Create a cpu bound kthread * @threadfn: the function to run until signal_pending(current). @@ -452,7 +480,7 @@ struct task_struct *kthread_create_on_cpu(int (*threadfn)(void *data), cpu); if (IS_ERR(p)) return p; - kthread_bind(p, cpu); + new_kthread_bind(p, cpu); /* CPU hotplug need to bind once again when unparking the thread. */ set_bit(KTHREAD_IS_PER_CPU, &to_kthread(p)->flags); to_kthread(p)->cpu = cpu; |