/*
* wait_task_inactive - wait for a thread to unschedule.
*
+ * If @match_state is nonzero, it's the @p->state value just checked and
+ * not expected to change. If it changes, i.e. @p might have woken up,
+ * then return zero. When we succeed in waiting for @p to be off its CPU,
+ * we return a positive number (its total switch count). If a second call
+ * a short while later returns the same number, the caller can be sure that
+ * @p has remained unscheduled the whole time.
+ *
* The caller must ensure that the task *will* unschedule sometime soon,
* else this function might spin for a *long* time. This function can't
* be called with interrupts off, or it may introduce deadlock with
* smp_call_function() if an IPI is sent by the same process we are
* waiting to become inactive.
*/
-void wait_task_inactive(struct task_struct *p)
+unsigned long wait_task_inactive(struct task_struct *p, long match_state)
{
unsigned long flags;
int running, on_rq;
+ unsigned long ncsw;
struct rq *rq;
for (;;) {
* return false if the runqueue has changed and p
* is actually now running somewhere else!
*/
- while (task_running(rq, p))
+ while (task_running(rq, p)) {
+ if (match_state && unlikely(p->state != match_state))
+ return 0;
cpu_relax();
+ }
/*
* Ok, time to look more closely! We need the rq
rq = task_rq_lock(p, &flags);
running = task_running(rq, p);
on_rq = p->se.on_rq;
+ ncsw = 0;
+ if (!match_state || p->state == match_state) {
+ ncsw = p->nivcsw + p->nvcsw;
+ if (unlikely(!ncsw))
+ ncsw = 1;
+ }
task_rq_unlock(rq, &flags);
+ /*
+ * If it changed from the expected state, bail out now.
+ */
+ if (unlikely(!ncsw))
+ break;
+
/*
* Was it really running after all now that we
* checked with the proper locks actually held?
*/
break;
}
+
+ return ncsw;
}
/***
return -EPERM;
}
+ if (user) {
#ifdef CONFIG_RT_GROUP_SCHED
- /*
- * Do not allow realtime tasks into groups that have no runtime
- * assigned.
- */
- if (user
- && rt_policy(policy) && task_group(p)->rt_bandwidth.rt_runtime == 0)
- return -EPERM;
+ /*
+ * Do not allow realtime tasks into groups that have no runtime
+ * assigned.
+ */
+ if (rt_policy(policy) && task_group(p)->rt_bandwidth.rt_runtime == 0)
+ return -EPERM;
#endif
- retval = security_task_setscheduler(p, policy, param);
- if (retval)
- return retval;
+ retval = security_task_setscheduler(p, policy, param);
+ if (retval)
+ return retval;
+ }
+
/*
* make sure no PI-waiters arrive (or leave) while we are
* changing the priority of the task:
.priority = 10
};
-void __init migration_init(void)
+static int __init migration_init(void)
{
void *cpu = (void *)(long)smp_processor_id();
int err;
BUG_ON(err == NOTIFY_BAD);
migration_call(&migration_notifier, CPU_ONLINE, cpu);
register_cpu_notifier(&migration_notifier);
+
+ return err;
}
+early_initcall(migration_init);
#endif
#ifdef CONFIG_SMP
}
#ifdef CONFIG_SCHED_MC
-static ssize_t sched_mc_power_savings_show(struct sys_device *dev,
- struct sysdev_attribute *attr, char *page)
+static ssize_t sched_mc_power_savings_show(struct sysdev_class *class,
+ char *page)
{
return sprintf(page, "%u\n", sched_mc_power_savings);
}
-static ssize_t sched_mc_power_savings_store(struct sys_device *dev,
- struct sysdev_attribute *attr,
+static ssize_t sched_mc_power_savings_store(struct sysdev_class *class,
const char *buf, size_t count)
{
return sched_power_savings_store(buf, count, 0);
}
-static SYSDEV_ATTR(sched_mc_power_savings, 0644, sched_mc_power_savings_show,
- sched_mc_power_savings_store);
+static SYSDEV_CLASS_ATTR(sched_mc_power_savings, 0644,
+ sched_mc_power_savings_show,
+ sched_mc_power_savings_store);
#endif
#ifdef CONFIG_SCHED_SMT
-static ssize_t sched_smt_power_savings_show(struct sys_device *dev,
- struct sysdev_attribute *attr, char *page)
+static ssize_t sched_smt_power_savings_show(struct sysdev_class *dev,
+ char *page)
{
return sprintf(page, "%u\n", sched_smt_power_savings);
}
-static ssize_t sched_smt_power_savings_store(struct sys_device *dev,
- struct sysdev_attribute *attr,
+static ssize_t sched_smt_power_savings_store(struct sysdev_class *dev,
const char *buf, size_t count)
{
return sched_power_savings_store(buf, count, 1);
}
-static SYSDEV_ATTR(sched_smt_power_savings, 0644, sched_smt_power_savings_show,
+static SYSDEV_CLASS_ATTR(sched_smt_power_savings, 0644,
+ sched_smt_power_savings_show,
sched_smt_power_savings_store);
#endif