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authorLinus Torvalds <torvalds@linux-foundation.org>2008-09-23 14:57:36 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2008-09-23 14:57:36 -0700
commit8553f321e0fd29821135ac4797b5f37bf80ae2e9 (patch)
treefa64ef70c4e503f62a09b56b792bb63b791aa121 /kernel
parentbe3be8905854d2fcf6030f1da9ebc221e9e2c5f1 (diff)
parentf8e256c687eb53850685747757c8d75e58756e15 (diff)
Merge branch 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: timers: fix build error in !oneshot case x86: c1e_idle: don't mark TSC unstable if CPU has invariant TSC x86: prevent C-states hang on AMD C1E enabled machines clockevents: prevent mode mismatch on cpu online clockevents: check broadcast device not tick device clockevents: prevent stale tick_next_period for onlining CPUs x86: prevent stale state of c1e_mask across CPU offline/online clockevents: prevent cpu online to interfere with nohz
Diffstat (limited to 'kernel')
-rw-r--r--kernel/time/tick-broadcast.c12
-rw-r--r--kernel/time/tick-common.c10
-rw-r--r--kernel/time/tick-internal.h7
-rw-r--r--kernel/time/tick-sched.c11
4 files changed, 30 insertions, 10 deletions
diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c
index f1f3eee28113..bd7034542399 100644
--- a/kernel/time/tick-broadcast.c
+++ b/kernel/time/tick-broadcast.c
@@ -235,7 +235,7 @@ static void tick_do_broadcast_on_off(void *why)
case CLOCK_EVT_NOTIFY_BROADCAST_FORCE:
if (!cpu_isset(cpu, tick_broadcast_mask)) {
cpu_set(cpu, tick_broadcast_mask);
- if (td->mode == TICKDEV_MODE_PERIODIC)
+ if (bc->mode == TICKDEV_MODE_PERIODIC)
clockevents_shutdown(dev);
}
if (*reason == CLOCK_EVT_NOTIFY_BROADCAST_FORCE)
@@ -245,7 +245,7 @@ static void tick_do_broadcast_on_off(void *why)
if (!tick_broadcast_force &&
cpu_isset(cpu, tick_broadcast_mask)) {
cpu_clear(cpu, tick_broadcast_mask);
- if (td->mode == TICKDEV_MODE_PERIODIC)
+ if (bc->mode == TICKDEV_MODE_PERIODIC)
tick_setup_periodic(dev, 0);
}
break;
@@ -575,4 +575,12 @@ void tick_shutdown_broadcast_oneshot(unsigned int *cpup)
spin_unlock_irqrestore(&tick_broadcast_lock, flags);
}
+/*
+ * Check, whether the broadcast device is in one shot mode
+ */
+int tick_broadcast_oneshot_active(void)
+{
+ return tick_broadcast_device.mode == TICKDEV_MODE_ONESHOT;
+}
+
#endif
diff --git a/kernel/time/tick-common.c b/kernel/time/tick-common.c
index 019315ebf9de..df12434b43ca 100644
--- a/kernel/time/tick-common.c
+++ b/kernel/time/tick-common.c
@@ -33,7 +33,7 @@ DEFINE_PER_CPU(struct tick_device, tick_cpu_device);
*/
ktime_t tick_next_period;
ktime_t tick_period;
-int tick_do_timer_cpu __read_mostly = -1;
+int tick_do_timer_cpu __read_mostly = TICK_DO_TIMER_BOOT;
DEFINE_SPINLOCK(tick_device_lock);
/*
@@ -109,7 +109,8 @@ void tick_setup_periodic(struct clock_event_device *dev, int broadcast)
if (!tick_device_is_functional(dev))
return;
- if (dev->features & CLOCK_EVT_FEAT_PERIODIC) {
+ if ((dev->features & CLOCK_EVT_FEAT_PERIODIC) &&
+ !tick_broadcast_oneshot_active()) {
clockevents_set_mode(dev, CLOCK_EVT_MODE_PERIODIC);
} else {
unsigned long seq;
@@ -148,7 +149,7 @@ static void tick_setup_device(struct tick_device *td,
* If no cpu took the do_timer update, assign it to
* this cpu:
*/
- if (tick_do_timer_cpu == -1) {
+ if (tick_do_timer_cpu == TICK_DO_TIMER_BOOT) {
tick_do_timer_cpu = cpu;
tick_next_period = ktime_get();
tick_period = ktime_set(0, NSEC_PER_SEC / HZ);
@@ -300,7 +301,8 @@ static void tick_shutdown(unsigned int *cpup)
if (*cpup == tick_do_timer_cpu) {
int cpu = first_cpu(cpu_online_map);
- tick_do_timer_cpu = (cpu != NR_CPUS) ? cpu : -1;
+ tick_do_timer_cpu = (cpu != NR_CPUS) ? cpu :
+ TICK_DO_TIMER_NONE;
}
spin_unlock_irqrestore(&tick_device_lock, flags);
}
diff --git a/kernel/time/tick-internal.h b/kernel/time/tick-internal.h
index 6e9db9734aa6..469248782c23 100644
--- a/kernel/time/tick-internal.h
+++ b/kernel/time/tick-internal.h
@@ -1,6 +1,10 @@
/*
* tick internal variable and functions used by low/high res code
*/
+
+#define TICK_DO_TIMER_NONE -1
+#define TICK_DO_TIMER_BOOT -2
+
DECLARE_PER_CPU(struct tick_device, tick_cpu_device);
extern spinlock_t tick_device_lock;
extern ktime_t tick_next_period;
@@ -31,6 +35,7 @@ extern void tick_broadcast_oneshot_control(unsigned long reason);
extern void tick_broadcast_switch_to_oneshot(void);
extern void tick_shutdown_broadcast_oneshot(unsigned int *cpup);
extern int tick_resume_broadcast_oneshot(struct clock_event_device *bc);
+extern int tick_broadcast_oneshot_active(void);
# else /* BROADCAST */
static inline void tick_broadcast_setup_oneshot(struct clock_event_device *bc)
{
@@ -39,6 +44,7 @@ static inline void tick_broadcast_setup_oneshot(struct clock_event_device *bc)
static inline void tick_broadcast_oneshot_control(unsigned long reason) { }
static inline void tick_broadcast_switch_to_oneshot(void) { }
static inline void tick_shutdown_broadcast_oneshot(unsigned int *cpup) { }
+static inline int tick_broadcast_oneshot_active(void) { return 0; }
# endif /* !BROADCAST */
#else /* !ONESHOT */
@@ -68,6 +74,7 @@ static inline int tick_resume_broadcast_oneshot(struct clock_event_device *bc)
{
return 0;
}
+static inline int tick_broadcast_oneshot_active(void) { return 0; }
#endif /* !TICK_ONESHOT */
/*
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index a87b0468568b..39019b3f7621 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -75,6 +75,9 @@ 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);
}
@@ -221,7 +224,7 @@ 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))
@@ -303,7 +306,7 @@ 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 +471,7 @@ 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 +573,7 @@ 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