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authorArjan van de Ven <arjan@linux.intel.com>2008-10-17 09:20:26 -0700
committerArjan van de Ven <arjan@linux.intel.com>2008-10-17 09:20:26 -0700
commit651dab4264e4ba0e563f5ff56f748127246e9065 (patch)
tree016630974bdcb00fe529b673f96d389e0fd6dc94 /kernel/time/tick-sched.c
parent40b8606253552109815786e5d4b0de98782d31f5 (diff)
parent2e532d68a2b3e2aa6b19731501222069735c741c (diff)
downloadlwn-651dab4264e4ba0e563f5ff56f748127246e9065.tar.gz
lwn-651dab4264e4ba0e563f5ff56f748127246e9065.zip
Merge commit 'linus/master' into merge-linus
Conflicts: arch/x86/kvm/i8254.c
Diffstat (limited to 'kernel/time/tick-sched.c')
-rw-r--r--kernel/time/tick-sched.c26
1 files changed, 19 insertions, 7 deletions
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index b33be61c0f6b..a547be11cf97 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -20,6 +20,7 @@
#include <linux/profile.h>
#include <linux/sched.h>
#include <linux/tick.h>
+#include <linux/module.h>
#include <asm/irq_regs.h>
@@ -75,6 +76,9 @@ static void tick_do_update_jiffies64(ktime_t now)
incr * ticks);
}
do_timer(++ticks);
+
+ /* Keep the tick_next_period variable up to date */
+ tick_next_period = ktime_add(last_jiffies_update, tick_period);
}
write_sequnlock(&xtime_lock);
}
@@ -187,9 +191,17 @@ u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time)
{
struct tick_sched *ts = &per_cpu(tick_cpu_sched, cpu);
- *last_update_time = ktime_to_us(ts->idle_lastupdate);
+ if (!tick_nohz_enabled)
+ return -1;
+
+ if (ts->idle_active)
+ *last_update_time = ktime_to_us(ts->idle_lastupdate);
+ else
+ *last_update_time = ktime_to_us(ktime_get());
+
return ktime_to_us(ts->idle_sleeptime);
}
+EXPORT_SYMBOL_GPL(get_cpu_idle_time_us);
/**
* tick_nohz_stop_sched_tick - stop the idle tick from the idle task
@@ -221,7 +233,7 @@ void tick_nohz_stop_sched_tick(int inidle)
*/
if (unlikely(!cpu_online(cpu))) {
if (cpu == tick_do_timer_cpu)
- tick_do_timer_cpu = -1;
+ tick_do_timer_cpu = TICK_DO_TIMER_NONE;
}
if (unlikely(ts->nohz_mode == NOHZ_MODE_INACTIVE))
@@ -258,7 +270,7 @@ void tick_nohz_stop_sched_tick(int inidle)
next_jiffies = get_next_timer_interrupt(last_jiffies);
delta_jiffies = next_jiffies - last_jiffies;
- if (rcu_needs_cpu(cpu))
+ if (rcu_needs_cpu(cpu) || printk_needs_cpu(cpu))
delta_jiffies = 1;
/*
* Do not stop the tick, if we are only one off
@@ -303,7 +315,7 @@ void tick_nohz_stop_sched_tick(int inidle)
* invoked.
*/
if (cpu == tick_do_timer_cpu)
- tick_do_timer_cpu = -1;
+ tick_do_timer_cpu = TICK_DO_TIMER_NONE;
ts->idle_sleeps++;
@@ -468,7 +480,7 @@ static void tick_nohz_handler(struct clock_event_device *dev)
* this duty, then the jiffies update is still serialized by
* xtime_lock.
*/
- if (unlikely(tick_do_timer_cpu == -1))
+ if (unlikely(tick_do_timer_cpu == TICK_DO_TIMER_NONE))
tick_do_timer_cpu = cpu;
/* Check, if the jiffies need an update */
@@ -570,7 +582,7 @@ static enum hrtimer_restart tick_sched_timer(struct hrtimer *timer)
* this duty, then the jiffies update is still serialized by
* xtime_lock.
*/
- if (unlikely(tick_do_timer_cpu == -1))
+ if (unlikely(tick_do_timer_cpu == TICK_DO_TIMER_NONE))
tick_do_timer_cpu = cpu;
#endif
@@ -622,7 +634,7 @@ void tick_setup_sched_timer(void)
*/
hrtimer_init(&ts->sched_timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
ts->sched_timer.function = tick_sched_timer;
- ts->sched_timer.cb_mode = HRTIMER_CB_IRQSAFE_NO_SOFTIRQ;
+ ts->sched_timer.cb_mode = HRTIMER_CB_IRQSAFE_PERCPU;
/* Get the next period (per cpu) */
hrtimer_set_expires(&ts->sched_timer, tick_init_jiffy_update());