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Diffstat (limited to 'kernel/timer.c')
-rw-r--r--kernel/timer.c100
1 files changed, 60 insertions, 40 deletions
diff --git a/kernel/timer.c b/kernel/timer.c
index fe3a9a9f8328..ab189dd187cb 100644
--- a/kernel/timer.c
+++ b/kernel/timer.c
@@ -86,7 +86,8 @@ struct tvec_t_base_s {
} ____cacheline_aligned_in_smp;
typedef struct tvec_t_base_s tvec_base_t;
-static DEFINE_PER_CPU(tvec_base_t, tvec_bases);
+static DEFINE_PER_CPU(tvec_base_t *, tvec_bases);
+static tvec_base_t boot_tvec_bases;
static inline void set_running_timer(tvec_base_t *base,
struct timer_list *timer)
@@ -157,7 +158,7 @@ EXPORT_SYMBOL(__init_timer_base);
void fastcall init_timer(struct timer_list *timer)
{
timer->entry.next = NULL;
- timer->base = &per_cpu(tvec_bases, raw_smp_processor_id()).t_base;
+ timer->base = &per_cpu(tvec_bases, raw_smp_processor_id())->t_base;
}
EXPORT_SYMBOL(init_timer);
@@ -218,7 +219,7 @@ int __mod_timer(struct timer_list *timer, unsigned long expires)
ret = 1;
}
- new_base = &__get_cpu_var(tvec_bases);
+ new_base = __get_cpu_var(tvec_bases);
if (base != &new_base->t_base) {
/*
@@ -258,7 +259,7 @@ EXPORT_SYMBOL(__mod_timer);
*/
void add_timer_on(struct timer_list *timer, int cpu)
{
- tvec_base_t *base = &per_cpu(tvec_bases, cpu);
+ tvec_base_t *base = per_cpu(tvec_bases, cpu);
unsigned long flags;
BUG_ON(timer_pending(timer) || !timer->function);
@@ -489,10 +490,22 @@ unsigned long next_timer_interrupt(void)
struct list_head *list;
struct timer_list *nte;
unsigned long expires;
+ unsigned long hr_expires = MAX_JIFFY_OFFSET;
+ ktime_t hr_delta;
tvec_t *varray[4];
int i, j;
- base = &__get_cpu_var(tvec_bases);
+ hr_delta = hrtimer_get_next_event();
+ if (hr_delta.tv64 != KTIME_MAX) {
+ struct timespec tsdelta;
+ tsdelta = ktime_to_timespec(hr_delta);
+ hr_expires = timespec_to_jiffies(&tsdelta);
+ if (hr_expires < 3)
+ return hr_expires + jiffies;
+ }
+ hr_expires += jiffies;
+
+ base = __get_cpu_var(tvec_bases);
spin_lock(&base->t_base.lock);
expires = base->timer_jiffies + (LONG_MAX >> 1);
list = NULL;
@@ -542,6 +555,10 @@ found:
}
}
spin_unlock(&base->t_base.lock);
+
+ if (time_before(hr_expires, expires))
+ return hr_expires;
+
return expires;
}
#endif
@@ -680,18 +697,9 @@ static void second_overflow(void)
/*
* Compute the frequency estimate and additional phase adjustment due
- * to frequency error for the next second. When the PPS signal is
- * engaged, gnaw on the watchdog counter and update the frequency
- * computed by the pll and the PPS signal.
+ * to frequency error for the next second.
*/
- pps_valid++;
- if (pps_valid == PPS_VALID) { /* PPS signal lost */
- pps_jitter = MAXTIME;
- pps_stabil = MAXFREQ;
- time_status &= ~(STA_PPSSIGNAL | STA_PPSJITTER |
- STA_PPSWANDER | STA_PPSERROR);
- }
- ltemp = time_freq + pps_freq;
+ ltemp = time_freq;
time_adj += shift_right(ltemp,(SHIFT_USEC + SHIFT_HZ - SHIFT_SCALE));
#if HZ == 100
@@ -885,7 +893,7 @@ EXPORT_SYMBOL(xtime_lock);
*/
static void run_timer_softirq(struct softirq_action *h)
{
- tvec_base_t *base = &__get_cpu_var(tvec_bases);
+ tvec_base_t *base = __get_cpu_var(tvec_bases);
hrtimer_run_queues();
if (time_after_eq(jiffies, base->timer_jiffies))
@@ -898,6 +906,7 @@ static void run_timer_softirq(struct softirq_action *h)
void run_local_timers(void)
{
raise_softirq(TIMER_SOFTIRQ);
+ softlockup_tick();
}
/*
@@ -925,8 +934,9 @@ static inline void update_times(void)
void do_timer(struct pt_regs *regs)
{
jiffies_64++;
+ /* prevent loading jiffies before storing new jiffies_64 value. */
+ barrier();
update_times();
- softlockup_tick(regs);
}
#ifdef __ARCH_WANT_SYS_ALARM
@@ -937,19 +947,7 @@ void do_timer(struct pt_regs *regs)
*/
asmlinkage unsigned long sys_alarm(unsigned int seconds)
{
- struct itimerval it_new, it_old;
- unsigned int oldalarm;
-
- it_new.it_interval.tv_sec = it_new.it_interval.tv_usec = 0;
- it_new.it_value.tv_sec = seconds;
- it_new.it_value.tv_usec = 0;
- do_setitimer(ITIMER_REAL, &it_new, &it_old);
- oldalarm = it_old.it_value.tv_sec;
- /* ehhh.. We can't return 0 if we have an alarm pending.. */
- /* And we'd better return too much than too little anyway */
- if ((!oldalarm && it_old.it_value.tv_usec) || it_old.it_value.tv_usec >= 500000)
- oldalarm++;
- return oldalarm;
+ return alarm_setitimer(seconds);
}
#endif
@@ -1238,12 +1236,32 @@ asmlinkage long sys_sysinfo(struct sysinfo __user *info)
return 0;
}
-static void __devinit init_timers_cpu(int cpu)
+static int __devinit init_timers_cpu(int cpu)
{
int j;
tvec_base_t *base;
- base = &per_cpu(tvec_bases, cpu);
+ base = per_cpu(tvec_bases, cpu);
+ if (!base) {
+ static char boot_done;
+
+ /*
+ * Cannot do allocation in init_timers as that runs before the
+ * allocator initializes (and would waste memory if there are
+ * more possible CPUs than will ever be installed/brought up).
+ */
+ if (boot_done) {
+ base = kmalloc_node(sizeof(*base), GFP_KERNEL,
+ cpu_to_node(cpu));
+ if (!base)
+ return -ENOMEM;
+ memset(base, 0, sizeof(*base));
+ } else {
+ base = &boot_tvec_bases;
+ boot_done = 1;
+ }
+ per_cpu(tvec_bases, cpu) = base;
+ }
spin_lock_init(&base->t_base.lock);
for (j = 0; j < TVN_SIZE; j++) {
INIT_LIST_HEAD(base->tv5.vec + j);
@@ -1255,6 +1273,7 @@ static void __devinit init_timers_cpu(int cpu)
INIT_LIST_HEAD(base->tv1.vec + j);
base->timer_jiffies = jiffies;
+ return 0;
}
#ifdef CONFIG_HOTPLUG_CPU
@@ -1277,8 +1296,8 @@ static void __devinit migrate_timers(int cpu)
int i;
BUG_ON(cpu_online(cpu));
- old_base = &per_cpu(tvec_bases, cpu);
- new_base = &get_cpu_var(tvec_bases);
+ old_base = per_cpu(tvec_bases, cpu);
+ new_base = get_cpu_var(tvec_bases);
local_irq_disable();
spin_lock(&new_base->t_base.lock);
@@ -1308,7 +1327,8 @@ static int __devinit timer_cpu_notify(struct notifier_block *self,
long cpu = (long)hcpu;
switch(action) {
case CPU_UP_PREPARE:
- init_timers_cpu(cpu);
+ if (init_timers_cpu(cpu) < 0)
+ return NOTIFY_BAD;
break;
#ifdef CONFIG_HOTPLUG_CPU
case CPU_DEAD:
@@ -1336,8 +1356,8 @@ void __init init_timers(void)
#ifdef CONFIG_TIME_INTERPOLATION
-struct time_interpolator *time_interpolator;
-static struct time_interpolator *time_interpolator_list;
+struct time_interpolator *time_interpolator __read_mostly;
+static struct time_interpolator *time_interpolator_list __read_mostly;
static DEFINE_SPINLOCK(time_interpolator_lock);
static inline u64 time_interpolator_get_cycles(unsigned int src)
@@ -1351,10 +1371,10 @@ static inline u64 time_interpolator_get_cycles(unsigned int src)
return x();
case TIME_SOURCE_MMIO64 :
- return readq((void __iomem *) time_interpolator->addr);
+ return readq_relaxed((void __iomem *)time_interpolator->addr);
case TIME_SOURCE_MMIO32 :
- return readl((void __iomem *) time_interpolator->addr);
+ return readl_relaxed((void __iomem *)time_interpolator->addr);
default: return get_cycles();
}
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