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authorLinus Torvalds <torvalds@linux-foundation.org>2011-05-23 11:30:28 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2011-05-23 11:30:28 -0700
commit30cb6d5f2eb24d15d20139d5ceefaccc68734bd7 (patch)
tree773c5a98645e4b945343caddcfe5af365566ccc5 /kernel
parent4867faab1e3eb8cc3f74e390357615d9b8e8cda6 (diff)
parent68fa61c026057a39d6ccb850aa8785043afbee02 (diff)
Merge branch 'timers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'timers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: hrtimers: Reorder clock bases hrtimers: Avoid touching inactive timer bases hrtimers: Make struct hrtimer_cpu_base layout less stupid timerfd: Manage cancelable timers in timerfd clockevents: Move C3 stop test outside lock alarmtimer: Drop device refcount after rtc_open() alarmtimer: Check return value of class_find_device() timerfd: Allow timers to be cancelled when clock was set hrtimers: Prepare for cancel on clock was set timers
Diffstat (limited to 'kernel')
-rw-r--r--kernel/hrtimer.c162
-rw-r--r--kernel/posix-cpu-timers.c4
-rw-r--r--kernel/posix-timers.c2
-rw-r--r--kernel/time/alarmtimer.c16
-rw-r--r--kernel/time/tick-broadcast.c16
-rw-r--r--kernel/time/timekeeping.c17
6 files changed, 125 insertions, 92 deletions
diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c
index dbbbf7d4308..c541ee527ec 100644
--- a/kernel/hrtimer.c
+++ b/kernel/hrtimer.c
@@ -64,17 +64,20 @@ DEFINE_PER_CPU(struct hrtimer_cpu_base, hrtimer_bases) =
.clock_base =
{
{
- .index = CLOCK_REALTIME,
- .get_time = &ktime_get_real,
+ .index = HRTIMER_BASE_MONOTONIC,
+ .clockid = CLOCK_MONOTONIC,
+ .get_time = &ktime_get,
.resolution = KTIME_LOW_RES,
},
{
- .index = CLOCK_MONOTONIC,
- .get_time = &ktime_get,
+ .index = HRTIMER_BASE_REALTIME,
+ .clockid = CLOCK_REALTIME,
+ .get_time = &ktime_get_real,
.resolution = KTIME_LOW_RES,
},
{
- .index = CLOCK_BOOTTIME,
+ .index = HRTIMER_BASE_BOOTTIME,
+ .clockid = CLOCK_BOOTTIME,
.get_time = &ktime_get_boottime,
.resolution = KTIME_LOW_RES,
},
@@ -196,7 +199,7 @@ switch_hrtimer_base(struct hrtimer *timer, struct hrtimer_clock_base *base,
struct hrtimer_cpu_base *new_cpu_base;
int this_cpu = smp_processor_id();
int cpu = hrtimer_get_target(this_cpu, pinned);
- int basenum = hrtimer_clockid_to_base(base->index);
+ int basenum = base->index;
again:
new_cpu_base = &per_cpu(hrtimer_bases, cpu);
@@ -621,66 +624,6 @@ static int hrtimer_reprogram(struct hrtimer *timer,
return res;
}
-
-/*
- * Retrigger next event is called after clock was set
- *
- * Called with interrupts disabled via on_each_cpu()
- */
-static void retrigger_next_event(void *arg)
-{
- struct hrtimer_cpu_base *base;
- struct timespec realtime_offset, wtm, sleep;
-
- if (!hrtimer_hres_active())
- return;
-
- get_xtime_and_monotonic_and_sleep_offset(&realtime_offset, &wtm,
- &sleep);
- set_normalized_timespec(&realtime_offset, -wtm.tv_sec, -wtm.tv_nsec);
-
- base = &__get_cpu_var(hrtimer_bases);
-
- /* Adjust CLOCK_REALTIME offset */
- raw_spin_lock(&base->lock);
- base->clock_base[HRTIMER_BASE_REALTIME].offset =
- timespec_to_ktime(realtime_offset);
- base->clock_base[HRTIMER_BASE_BOOTTIME].offset =
- timespec_to_ktime(sleep);
-
- hrtimer_force_reprogram(base, 0);
- raw_spin_unlock(&base->lock);
-}
-
-/*
- * Clock realtime was set
- *
- * Change the offset of the realtime clock vs. the monotonic
- * clock.
- *
- * We might have to reprogram the high resolution timer interrupt. On
- * SMP we call the architecture specific code to retrigger _all_ high
- * resolution timer interrupts. On UP we just disable interrupts and
- * call the high resolution interrupt code.
- */
-void clock_was_set(void)
-{
- /* Retrigger the CPU local events everywhere */
- on_each_cpu(retrigger_next_event, NULL, 1);
-}
-
-/*
- * During resume we might have to reprogram the high resolution timer
- * interrupt (on the local CPU):
- */
-void hres_timers_resume(void)
-{
- WARN_ONCE(!irqs_disabled(),
- KERN_INFO "hres_timers_resume() called with IRQs enabled!");
-
- retrigger_next_event(NULL);
-}
-
/*
* Initialize the high resolution related parts of cpu_base
*/
@@ -715,11 +658,39 @@ static inline int hrtimer_enqueue_reprogram(struct hrtimer *timer,
}
/*
+ * Retrigger next event is called after clock was set
+ *
+ * Called with interrupts disabled via on_each_cpu()
+ */
+static void retrigger_next_event(void *arg)
+{
+ struct hrtimer_cpu_base *base = &__get_cpu_var(hrtimer_bases);
+ struct timespec realtime_offset, xtim, wtm, sleep;
+
+ if (!hrtimer_hres_active())
+ return;
+
+ /* Optimized out for !HIGH_RES */
+ get_xtime_and_monotonic_and_sleep_offset(&xtim, &wtm, &sleep);
+ set_normalized_timespec(&realtime_offset, -wtm.tv_sec, -wtm.tv_nsec);
+
+ /* Adjust CLOCK_REALTIME offset */
+ raw_spin_lock(&base->lock);
+ base->clock_base[HRTIMER_BASE_REALTIME].offset =
+ timespec_to_ktime(realtime_offset);
+ base->clock_base[HRTIMER_BASE_BOOTTIME].offset =
+ timespec_to_ktime(sleep);
+
+ hrtimer_force_reprogram(base, 0);
+ raw_spin_unlock(&base->lock);
+}
+
+/*
* Switch to high resolution mode
*/
static int hrtimer_switch_to_hres(void)
{
- int cpu = smp_processor_id();
+ int i, cpu = smp_processor_id();
struct hrtimer_cpu_base *base = &per_cpu(hrtimer_bases, cpu);
unsigned long flags;
@@ -735,9 +706,8 @@ static int hrtimer_switch_to_hres(void)
return 0;
}
base->hres_active = 1;
- base->clock_base[HRTIMER_BASE_REALTIME].resolution = KTIME_HIGH_RES;
- base->clock_base[HRTIMER_BASE_MONOTONIC].resolution = KTIME_HIGH_RES;
- base->clock_base[HRTIMER_BASE_BOOTTIME].resolution = KTIME_HIGH_RES;
+ for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++)
+ base->clock_base[i].resolution = KTIME_HIGH_RES;
tick_setup_sched_timer();
@@ -761,9 +731,43 @@ static inline int hrtimer_enqueue_reprogram(struct hrtimer *timer,
return 0;
}
static inline void hrtimer_init_hres(struct hrtimer_cpu_base *base) { }
+static inline void retrigger_next_event(void *arg) { }
#endif /* CONFIG_HIGH_RES_TIMERS */
+/*
+ * Clock realtime was set
+ *
+ * Change the offset of the realtime clock vs. the monotonic
+ * clock.
+ *
+ * We might have to reprogram the high resolution timer interrupt. On
+ * SMP we call the architecture specific code to retrigger _all_ high
+ * resolution timer interrupts. On UP we just disable interrupts and
+ * call the high resolution interrupt code.
+ */
+void clock_was_set(void)
+{
+#ifdef CONFIG_HIGHRES_TIMERS
+ /* Retrigger the CPU local events everywhere */
+ on_each_cpu(retrigger_next_event, NULL, 1);
+#endif
+ timerfd_clock_was_set();
+}
+
+/*
+ * During resume we might have to reprogram the high resolution timer
+ * interrupt (on the local CPU):
+ */
+void hrtimers_resume(void)
+{
+ WARN_ONCE(!irqs_disabled(),
+ KERN_INFO "hrtimers_resume() called with IRQs enabled!");
+
+ retrigger_next_event(NULL);
+ timerfd_clock_was_set();
+}
+
static inline void timer_stats_hrtimer_set_start_info(struct hrtimer *timer)
{
#ifdef CONFIG_TIMER_STATS
@@ -856,6 +860,7 @@ static int enqueue_hrtimer(struct hrtimer *timer,
debug_activate(timer);
timerqueue_add(&base->active, &timer->node);
+ base->cpu_base->active_bases |= 1 << base->index;
/*
* HRTIMER_STATE_ENQUEUED is or'ed to the current state to preserve the
@@ -897,6 +902,8 @@ static void __remove_hrtimer(struct hrtimer *timer,
#endif
}
timerqueue_del(&base->active, &timer->node);
+ if (!timerqueue_getnext(&base->active))
+ base->cpu_base->active_bases &= ~(1 << base->index);
out:
timer->state = newstate;
}
@@ -1234,7 +1241,6 @@ static void __run_hrtimer(struct hrtimer *timer, ktime_t *now)
void hrtimer_interrupt(struct clock_event_device *dev)
{
struct hrtimer_cpu_base *cpu_base = &__get_cpu_var(hrtimer_bases);
- struct hrtimer_clock_base *base;
ktime_t expires_next, now, entry_time, delta;
int i, retries = 0;
@@ -1256,12 +1262,15 @@ retry:
*/
cpu_base->expires_next.tv64 = KTIME_MAX;
- base = cpu_base->clock_base;
-
for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++) {
- ktime_t basenow;
+ struct hrtimer_clock_base *base;
struct timerqueue_node *node;
+ ktime_t basenow;
+
+ if (!(cpu_base->active_bases & (1 << i)))
+ continue;
+ base = cpu_base->clock_base + i;
basenow = ktime_add(now, base->offset);
while ((node = timerqueue_getnext(&base->active))) {
@@ -1294,7 +1303,6 @@ retry:
__run_hrtimer(timer, &basenow);
}
- base++;
}
/*
@@ -1525,7 +1533,7 @@ long __sched hrtimer_nanosleep_restart(struct restart_block *restart)
struct timespec __user *rmtp;
int ret = 0;
- hrtimer_init_on_stack(&t.timer, restart->nanosleep.index,
+ hrtimer_init_on_stack(&t.timer, restart->nanosleep.clockid,
HRTIMER_MODE_ABS);
hrtimer_set_expires_tv64(&t.timer, restart->nanosleep.expires);
@@ -1577,7 +1585,7 @@ long hrtimer_nanosleep(struct timespec *rqtp, struct timespec __user *rmtp,
restart = &current_thread_info()->restart_block;
restart->fn = hrtimer_nanosleep_restart;
- restart->nanosleep.index = t.timer.base->index;
+ restart->nanosleep.clockid = t.timer.base->clockid;
restart->nanosleep.rmtp = rmtp;
restart->nanosleep.expires = hrtimer_get_expires_tv64(&t.timer);
diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c
index 0791b13df7b..58f405b581e 100644
--- a/kernel/posix-cpu-timers.c
+++ b/kernel/posix-cpu-timers.c
@@ -1514,7 +1514,7 @@ static int posix_cpu_nsleep(const clockid_t which_clock, int flags,
return -EFAULT;
restart_block->fn = posix_cpu_nsleep_restart;
- restart_block->nanosleep.index = which_clock;
+ restart_block->nanosleep.clockid = which_clock;
restart_block->nanosleep.rmtp = rmtp;
restart_block->nanosleep.expires = timespec_to_ns(rqtp);
}
@@ -1523,7 +1523,7 @@ static int posix_cpu_nsleep(const clockid_t which_clock, int flags,
static long posix_cpu_nsleep_restart(struct restart_block *restart_block)
{
- clockid_t which_clock = restart_block->nanosleep.index;
+ clockid_t which_clock = restart_block->nanosleep.clockid;
struct timespec t;
struct itimerspec it;
int error;
diff --git a/kernel/posix-timers.c b/kernel/posix-timers.c
index e5498d7405c..a1b5edf1bf9 100644
--- a/kernel/posix-timers.c
+++ b/kernel/posix-timers.c
@@ -1056,7 +1056,7 @@ SYSCALL_DEFINE4(clock_nanosleep, const clockid_t, which_clock, int, flags,
*/
long clock_nanosleep_restart(struct restart_block *restart_block)
{
- clockid_t which_clock = restart_block->nanosleep.index;
+ clockid_t which_clock = restart_block->nanosleep.clockid;
struct k_clock *kc = clockid_to_kclock(which_clock);
if (WARN_ON_ONCE(!kc || !kc->nsleep_restart))
diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c
index 9265014cb4d..2d966244ea6 100644
--- a/kernel/time/alarmtimer.c
+++ b/kernel/time/alarmtimer.c
@@ -494,7 +494,7 @@ static int update_rmtp(ktime_t exp, enum alarmtimer_type type,
*/
static long __sched alarm_timer_nsleep_restart(struct restart_block *restart)
{
- enum alarmtimer_type type = restart->nanosleep.index;
+ enum alarmtimer_type type = restart->nanosleep.clockid;
ktime_t exp;
struct timespec __user *rmtp;
struct alarm alarm;
@@ -573,7 +573,7 @@ static int alarm_timer_nsleep(const clockid_t which_clock, int flags,
restart = &current_thread_info()->restart_block;
restart->fn = alarm_timer_nsleep_restart;
- restart->nanosleep.index = type;
+ restart->nanosleep.clockid = type;
restart->nanosleep.expires = exp.tv64;
restart->nanosleep.rmtp = rmtp;
ret = -ERESTART_RESTARTBLOCK;
@@ -669,12 +669,20 @@ static int __init has_wakealarm(struct device *dev, void *name_ptr)
*/
static int __init alarmtimer_init_late(void)
{
+ struct device *dev;
char *str;
/* Find an rtc device and init the rtc_timer */
- class_find_device(rtc_class, NULL, &str, has_wakealarm);
- if (str)
+ dev = class_find_device(rtc_class, NULL, &str, has_wakealarm);
+ /* If we have a device then str is valid. See has_wakealarm() */
+ if (dev) {
rtcdev = rtc_class_open(str);
+ /*
+ * Drop the reference we got in class_find_device,
+ * rtc_open takes its own.
+ */
+ put_device(dev);
+ }
if (!rtcdev) {
printk(KERN_WARNING "No RTC device found, ALARM timers will"
" not wake from suspend");
diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c
index 723c7637e55..c7218d13273 100644
--- a/kernel/time/tick-broadcast.c
+++ b/kernel/time/tick-broadcast.c
@@ -456,23 +456,27 @@ void tick_broadcast_oneshot_control(unsigned long reason)
unsigned long flags;
int cpu;
- raw_spin_lock_irqsave(&tick_broadcast_lock, flags);
-
/*
* Periodic mode does not care about the enter/exit of power
* states
*/
if (tick_broadcast_device.mode == TICKDEV_MODE_PERIODIC)
- goto out;
+ return;
- bc = tick_broadcast_device.evtdev;
+ /*
+ * We are called with preemtion disabled from the depth of the
+ * idle code, so we can't be moved away.
+ */
cpu = smp_processor_id();
td = &per_cpu(tick_cpu_device, cpu);
dev = td->evtdev;
if (!(dev->features & CLOCK_EVT_FEAT_C3STOP))
- goto out;
+ return;
+
+ bc = tick_broadcast_device.evtdev;
+ raw_spin_lock_irqsave(&tick_broadcast_lock, flags);
if (reason == CLOCK_EVT_NOTIFY_BROADCAST_ENTER) {
if (!cpumask_test_cpu(cpu, tick_get_broadcast_oneshot_mask())) {
cpumask_set_cpu(cpu, tick_get_broadcast_oneshot_mask());
@@ -489,8 +493,6 @@ void tick_broadcast_oneshot_control(unsigned long reason)
tick_program_event(dev->next_event, 1);
}
}
-
-out:
raw_spin_unlock_irqrestore(&tick_broadcast_lock, flags);
}
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index 8e6a05a5915..342408cf68d 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -680,7 +680,7 @@ static void timekeeping_resume(void)
clockevents_notify(CLOCK_EVT_NOTIFY_RESUME, NULL);
/* Resume hrtimers */
- hres_timers_resume();
+ hrtimers_resume();
}
static int timekeeping_suspend(void)
@@ -1099,6 +1099,21 @@ void get_xtime_and_monotonic_and_sleep_offset(struct timespec *xtim,
}
/**
+ * ktime_get_monotonic_offset() - get wall_to_monotonic in ktime_t format
+ */
+ktime_t ktime_get_monotonic_offset(void)
+{
+ unsigned long seq;
+ struct timespec wtom;
+
+ do {
+ seq = read_seqbegin(&xtime_lock);
+ wtom = wall_to_monotonic;
+ } while (read_seqretry(&xtime_lock, seq));
+ return timespec_to_ktime(wtom);
+}
+
+/**
* xtime_update() - advances the timekeeping infrastructure
* @ticks: number of ticks, that have elapsed since the last call.
*