* the target CPU.
*/
#ifdef CONFIG_SMP
-
-#ifndef tsk_is_polling
-#define tsk_is_polling(t) 0
-#endif
-
void resched_task(struct task_struct *p)
{
int cpu;
raw_spin_unlock_irqrestore(&rq->lock, flags);
}
-#ifdef CONFIG_NO_HZ
+#ifdef CONFIG_NO_HZ_COMMON
/*
* In the semi idle case, use the nearest busy cpu for migrating timers
* from an idle cpu. This is good for power-savings.
* account when the CPU goes back to idle and evaluates the timer
* wheel for the next timer event.
*/
-void wake_up_idle_cpu(int cpu)
+static void wake_up_idle_cpu(int cpu)
{
struct rq *rq = cpu_rq(cpu);
smp_send_reschedule(cpu);
}
+static bool wake_up_full_nohz_cpu(int cpu)
+{
+ if (tick_nohz_full_cpu(cpu)) {
+ if (cpu != smp_processor_id() ||
+ tick_nohz_tick_stopped())
+ smp_send_reschedule(cpu);
+ return true;
+ }
+
+ return false;
+}
+
+void wake_up_nohz_cpu(int cpu)
+{
+ if (!wake_up_full_nohz_cpu(cpu))
+ wake_up_idle_cpu(cpu);
+}
+
static inline bool got_nohz_idle_kick(void)
{
int cpu = smp_processor_id();
return idle_cpu(cpu) && test_bit(NOHZ_BALANCE_KICK, nohz_flags(cpu));
}
-#else /* CONFIG_NO_HZ */
+#else /* CONFIG_NO_HZ_COMMON */
static inline bool got_nohz_idle_kick(void)
{
return false;
}
-#endif /* CONFIG_NO_HZ */
+#endif /* CONFIG_NO_HZ_COMMON */
+
+#ifdef CONFIG_NO_HZ_FULL
+bool sched_can_stop_tick(void)
+{
+ struct rq *rq;
+
+ rq = this_rq();
+
+ /* Make sure rq->nr_running update is visible after the IPI */
+ smp_rmb();
+
+ /* More than one running task need preemption */
+ if (rq->nr_running > 1)
+ return false;
+
+ return true;
+}
+#endif /* CONFIG_NO_HZ_FULL */
void sched_avg_update(struct rq *rq)
{
void scheduler_ipi(void)
{
- if (llist_empty(&this_rq()->wake_list) && !got_nohz_idle_kick())
+ if (llist_empty(&this_rq()->wake_list) && !got_nohz_idle_kick()
+ && !tick_nohz_full_cpu(smp_processor_id()))
return;
/*
* somewhat pessimize the simple resched case.
*/
irq_enter();
+ tick_nohz_full_check();
sched_ttwu_pending();
/*
{
struct rq *rq = task_rq(p);
- BUG_ON(rq != this_rq());
- BUG_ON(p == current);
+ if (WARN_ON_ONCE(rq != this_rq()) ||
+ WARN_ON_ONCE(p == current))
+ return;
+
lockdep_assert_held(&rq->lock);
if (!raw_spin_trylock(&p->pi_lock)) {
kprobe_flush_task(prev);
put_task_struct(prev);
}
+
+ tick_nohz_task_switch(current);
}
#ifdef CONFIG_SMP
return load >> FSHIFT;
}
-#ifdef CONFIG_NO_HZ
+#ifdef CONFIG_NO_HZ_COMMON
/*
* Handle NO_HZ for the global load-average.
*
smp_wmb();
calc_load_idx++;
}
-#else /* !CONFIG_NO_HZ */
+#else /* !CONFIG_NO_HZ_COMMON */
static inline long calc_load_fold_idle(void) { return 0; }
static inline void calc_global_nohz(void) { }
-#endif /* CONFIG_NO_HZ */
+#endif /* CONFIG_NO_HZ_COMMON */
/*
* calc_load - update the avenrun load estimates 10 ticks after the
sched_avg_update(this_rq);
}
-#ifdef CONFIG_NO_HZ
+#ifdef CONFIG_NO_HZ_COMMON
/*
* There is no sane way to deal with nohz on smp when using jiffies because the
* cpu doing the jiffies update might drift wrt the cpu doing the jiffy reading
}
raw_spin_unlock(&this_rq->lock);
}
-#endif /* CONFIG_NO_HZ */
+#endif /* CONFIG_NO_HZ_COMMON */
/*
* Called from scheduler_tick()
rq->idle_balance = idle_cpu(cpu);
trigger_load_balance(rq, cpu);
#endif
+ rq_last_tick_reset(rq);
+}
+
+#ifdef CONFIG_NO_HZ_FULL
+/**
+ * scheduler_tick_max_deferment
+ *
+ * Keep at least one tick per second when a single
+ * active task is running because the scheduler doesn't
+ * yet completely support full dynticks environment.
+ *
+ * This makes sure that uptime, CFS vruntime, load
+ * balancing, etc... continue to move forward, even
+ * with a very low granularity.
+ */
+u64 scheduler_tick_max_deferment(void)
+{
+ struct rq *rq = this_rq();
+ unsigned long next, now = ACCESS_ONCE(jiffies);
+
+ next = rq->last_sched_tick + HZ;
+
+ if (time_before_eq(next, now))
+ return 0;
+
+ return jiffies_to_usecs(next - now) * NSEC_PER_USEC;
}
+#endif
notrace unsigned long get_parent_ip(unsigned long addr)
{
preempt_disable();
}
-#ifdef CONFIG_MUTEX_SPIN_ON_OWNER
-
-static inline bool owner_running(struct mutex *lock, struct task_struct *owner)
-{
- if (lock->owner != owner)
- return false;
-
- /*
- * Ensure we emit the owner->on_cpu, dereference _after_ checking
- * lock->owner still matches owner, if that fails, owner might
- * point to free()d memory, if it still matches, the rcu_read_lock()
- * ensures the memory stays valid.
- */
- barrier();
-
- return owner->on_cpu;
-}
-
-/*
- * Look out! "owner" is an entirely speculative pointer
- * access and not reliable.
- */
-int mutex_spin_on_owner(struct mutex *lock, struct task_struct *owner)
-{
- if (!sched_feat(OWNER_SPIN))
- return 0;
-
- rcu_read_lock();
- while (owner_running(lock, owner)) {
- if (need_resched())
- break;
-
- arch_mutex_cpu_relax();
- }
- rcu_read_unlock();
-
- /*
- * We break out the loop above on need_resched() and when the
- * owner changed, which is a sign for heavy contention. Return
- * success only when lock->owner is NULL.
- */
- return lock->owner == NULL;
-}
-#endif
-
#ifdef CONFIG_PREEMPT
/*
* this is the entry point to schedule() from in-kernel preemption
get_task_struct(p);
rcu_read_unlock();
+ if (p->flags & PF_NO_SETAFFINITY) {
+ retval = -EINVAL;
+ goto out_put_task;
+ }
if (!alloc_cpumask_var(&cpus_allowed, GFP_KERNEL)) {
retval = -ENOMEM;
goto out_put_task;
goto out;
}
- if (unlikely((p->flags & PF_THREAD_BOUND) && p != current)) {
- ret = -EINVAL;
- goto out;
- }
-
do_set_cpus_allowed(p, new_mask);
/* Can the task run on the task's current CPU? If so, we're done */
}
static int min_load_idx = 0;
-static int max_load_idx = CPU_LOAD_IDX_MAX;
+static int max_load_idx = CPU_LOAD_IDX_MAX-1;
static void
set_table_entry(struct ctl_table *entry,
INIT_LIST_HEAD(&rq->cfs_tasks);
rq_attach_root(rq, &def_root_domain);
-#ifdef CONFIG_NO_HZ
+#ifdef CONFIG_NO_HZ_COMMON
rq->nohz_flags = 0;
#endif
+#ifdef CONFIG_NO_HZ_FULL
+ rq->last_sched_tick = 0;
+#endif
#endif
init_rq_hrtick(rq);
atomic_set(&rq->nr_iowait, 0);