#endif
#ifdef CONFIG_SCHED_HRTICK
- unsigned long hrtick_flags;
- ktime_t hrtick_expire;
+#ifdef CONFIG_SMP
+ int hrtick_csd_pending;
+ struct call_single_data hrtick_csd;
+#endif
struct hrtimer hrtick_timer;
#endif
return rq;
}
-static void __resched_task(struct task_struct *p, int tif_bit);
-
-static inline void resched_task(struct task_struct *p)
-{
- __resched_task(p, TIF_NEED_RESCHED);
-}
-
#ifdef CONFIG_SCHED_HRTICK
/*
* Use HR-timers to deliver accurate preemption points.
* When we get rescheduled we reprogram the hrtick_timer outside of the
* rq->lock.
*/
-static inline void resched_hrt(struct task_struct *p)
-{
- __resched_task(p, TIF_HRTICK_RESCHED);
-}
-
-static inline void resched_rq(struct rq *rq)
-{
- unsigned long flags;
-
- spin_lock_irqsave(&rq->lock, flags);
- resched_task(rq->curr);
- spin_unlock_irqrestore(&rq->lock, flags);
-}
-
-enum {
- HRTICK_SET, /* re-programm hrtick_timer */
- HRTICK_RESET, /* not a new slice */
- HRTICK_BLOCK, /* stop hrtick operations */
-};
/*
* Use hrtick when:
{
if (!sched_feat(HRTICK))
return 0;
- if (unlikely(test_bit(HRTICK_BLOCK, &rq->hrtick_flags)))
+ if (!cpu_online(cpu_of(rq)))
return 0;
return hrtimer_is_hres_active(&rq->hrtick_timer);
}
-/*
- * Called to set the hrtick timer state.
- *
- * called with rq->lock held and irqs disabled
- */
-static void hrtick_start(struct rq *rq, u64 delay, int reset)
-{
- assert_spin_locked(&rq->lock);
-
- /*
- * preempt at: now + delay
- */
- rq->hrtick_expire =
- ktime_add_ns(rq->hrtick_timer.base->get_time(), delay);
- /*
- * indicate we need to program the timer
- */
- __set_bit(HRTICK_SET, &rq->hrtick_flags);
- if (reset)
- __set_bit(HRTICK_RESET, &rq->hrtick_flags);
-
- /*
- * New slices are called from the schedule path and don't need a
- * forced reschedule.
- */
- if (reset)
- resched_hrt(rq->curr);
-}
-
static void hrtick_clear(struct rq *rq)
{
if (hrtimer_active(&rq->hrtick_timer))
hrtimer_cancel(&rq->hrtick_timer);
}
-/*
- * Update the timer from the possible pending state.
- */
-static void hrtick_set(struct rq *rq)
-{
- ktime_t time;
- int set, reset;
- unsigned long flags;
-
- WARN_ON_ONCE(cpu_of(rq) != smp_processor_id());
-
- spin_lock_irqsave(&rq->lock, flags);
- set = __test_and_clear_bit(HRTICK_SET, &rq->hrtick_flags);
- reset = __test_and_clear_bit(HRTICK_RESET, &rq->hrtick_flags);
- time = rq->hrtick_expire;
- clear_thread_flag(TIF_HRTICK_RESCHED);
- spin_unlock_irqrestore(&rq->lock, flags);
-
- if (set) {
- hrtimer_start(&rq->hrtick_timer, time, HRTIMER_MODE_ABS);
- if (reset && !hrtimer_active(&rq->hrtick_timer))
- resched_rq(rq);
- } else
- hrtick_clear(rq);
-}
-
/*
* High-resolution timer tick.
* Runs from hardirq context with interrupts disabled.
}
#ifdef CONFIG_SMP
-static void hotplug_hrtick_disable(int cpu)
+/*
+ * called from hardirq (IPI) context
+ */
+static void __hrtick_start(void *arg)
{
- struct rq *rq = cpu_rq(cpu);
- unsigned long flags;
-
- spin_lock_irqsave(&rq->lock, flags);
- rq->hrtick_flags = 0;
- __set_bit(HRTICK_BLOCK, &rq->hrtick_flags);
- spin_unlock_irqrestore(&rq->lock, flags);
+ struct rq *rq = arg;
- hrtick_clear(rq);
+ spin_lock(&rq->lock);
+ hrtimer_restart(&rq->hrtick_timer);
+ rq->hrtick_csd_pending = 0;
+ spin_unlock(&rq->lock);
}
-static void hotplug_hrtick_enable(int cpu)
+/*
+ * Called to set the hrtick timer state.
+ *
+ * called with rq->lock held and irqs disabled
+ */
+static void hrtick_start(struct rq *rq, u64 delay)
{
- struct rq *rq = cpu_rq(cpu);
- unsigned long flags;
+ struct hrtimer *timer = &rq->hrtick_timer;
+ ktime_t time = ktime_add_ns(timer->base->get_time(), delay);
- spin_lock_irqsave(&rq->lock, flags);
- __clear_bit(HRTICK_BLOCK, &rq->hrtick_flags);
- spin_unlock_irqrestore(&rq->lock, flags);
+ timer->expires = time;
+
+ if (rq == this_rq()) {
+ hrtimer_restart(timer);
+ } else if (!rq->hrtick_csd_pending) {
+ __smp_call_function_single(cpu_of(rq), &rq->hrtick_csd);
+ rq->hrtick_csd_pending = 1;
+ }
}
static int
case CPU_DOWN_PREPARE_FROZEN:
case CPU_DEAD:
case CPU_DEAD_FROZEN:
- hotplug_hrtick_disable(cpu);
- return NOTIFY_OK;
-
- case CPU_UP_PREPARE:
- case CPU_UP_PREPARE_FROZEN:
- case CPU_DOWN_FAILED:
- case CPU_DOWN_FAILED_FROZEN:
- case CPU_ONLINE:
- case CPU_ONLINE_FROZEN:
- hotplug_hrtick_enable(cpu);
+ hrtick_clear(cpu_rq(cpu));
return NOTIFY_OK;
}
{
hotcpu_notifier(hotplug_hrtick, 0);
}
-#endif /* CONFIG_SMP */
+#else
+/*
+ * Called to set the hrtick timer state.
+ *
+ * called with rq->lock held and irqs disabled
+ */
+static void hrtick_start(struct rq *rq, u64 delay)
+{
+ hrtimer_start(&rq->hrtick_timer, ns_to_ktime(delay), HRTIMER_MODE_REL);
+}
-static void init_rq_hrtick(struct rq *rq)
+static void init_hrtick(void)
{
- rq->hrtick_flags = 0;
- hrtimer_init(&rq->hrtick_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
- rq->hrtick_timer.function = hrtick;
- rq->hrtick_timer.cb_mode = HRTIMER_CB_IRQSAFE_NO_SOFTIRQ;
}
+#endif /* CONFIG_SMP */
-void hrtick_resched(void)
+static void init_rq_hrtick(struct rq *rq)
{
- struct rq *rq;
- unsigned long flags;
+#ifdef CONFIG_SMP
+ rq->hrtick_csd_pending = 0;
- if (!test_thread_flag(TIF_HRTICK_RESCHED))
- return;
+ rq->hrtick_csd.flags = 0;
+ rq->hrtick_csd.func = __hrtick_start;
+ rq->hrtick_csd.info = rq;
+#endif
- local_irq_save(flags);
- rq = cpu_rq(smp_processor_id());
- hrtick_set(rq);
- local_irq_restore(flags);
+ hrtimer_init(&rq->hrtick_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+ rq->hrtick_timer.function = hrtick;
+ rq->hrtick_timer.cb_mode = HRTIMER_CB_IRQSAFE_NO_SOFTIRQ;
}
#else
static inline void hrtick_clear(struct rq *rq)
{
}
-static inline void hrtick_set(struct rq *rq)
-{
-}
-
static inline void init_rq_hrtick(struct rq *rq)
{
}
-void hrtick_resched(void)
-{
-}
-
static inline void init_hrtick(void)
{
}
#define tsk_is_polling(t) test_tsk_thread_flag(t, TIF_POLLING_NRFLAG)
#endif
-static void __resched_task(struct task_struct *p, int tif_bit)
+static void resched_task(struct task_struct *p)
{
int cpu;
assert_spin_locked(&task_rq(p)->lock);
- if (unlikely(test_tsk_thread_flag(p, tif_bit)))
+ if (unlikely(test_tsk_thread_flag(p, TIF_NEED_RESCHED)))
return;
- set_tsk_thread_flag(p, tif_bit);
+ set_tsk_thread_flag(p, TIF_NEED_RESCHED);
cpu = task_cpu(p);
if (cpu == smp_processor_id())
#endif /* CONFIG_NO_HZ */
#else /* !CONFIG_SMP */
-static void __resched_task(struct task_struct *p, int tif_bit)
+static void resched_task(struct task_struct *p)
{
assert_spin_locked(&task_rq(p)->lock);
- set_tsk_thread_flag(p, tif_bit);
+ set_tsk_need_resched(p);
}
#endif /* CONFIG_SMP */
struct task_struct *prev, *next;
unsigned long *switch_count;
struct rq *rq;
- int cpu, hrtick = sched_feat(HRTICK);
+ int cpu;
need_resched:
preempt_disable();
schedule_debug(prev);
- if (hrtick)
+ if (sched_feat(HRTICK))
hrtick_clear(rq);
/*
} else
spin_unlock_irq(&rq->lock);
- if (hrtick)
- hrtick_set(rq);
-
if (unlikely(reacquire_kernel_lock(current) < 0))
goto need_resched_nonpreemptible;
projects / linux-2.6 / commitdiff