diff options
Diffstat (limited to 'kernel/time')
| -rw-r--r-- | kernel/time/clockevents.c | 2 | ||||
| -rw-r--r-- | kernel/time/clocksource.c | 23 | ||||
| -rw-r--r-- | kernel/time/tick-broadcast.c | 2 | ||||
| -rw-r--r-- | kernel/time/tick-common.c | 12 | ||||
| -rw-r--r-- | kernel/time/tick-oneshot.c | 17 | ||||
| -rw-r--r-- | kernel/time/timekeeping.c | 9 |
6 files changed, 58 insertions, 7 deletions
diff --git a/kernel/time/clockevents.c b/kernel/time/clockevents.c index ab20ded013b..1ad6dd46111 100644 --- a/kernel/time/clockevents.c +++ b/kernel/time/clockevents.c @@ -55,6 +55,7 @@ unsigned long clockevent_delta2ns(unsigned long latch, return (unsigned long) clc; } +EXPORT_SYMBOL_GPL(clockevent_delta2ns); /** * clockevents_set_mode - set the operating mode of a clock event device @@ -188,6 +189,7 @@ void clockevents_register_device(struct clock_event_device *dev) spin_unlock(&clockevents_lock); } +EXPORT_SYMBOL_GPL(clockevents_register_device); /* * Noop handler when we shut down an event device diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c index ecfd7b5187e..592bf584d1d 100644 --- a/kernel/time/clocksource.c +++ b/kernel/time/clocksource.c @@ -402,9 +402,6 @@ int clocksource_register(struct clocksource *c) unsigned long flags; int ret; - /* save mult_orig on registration */ - c->mult_orig = c->mult; - spin_lock_irqsave(&clocksource_lock, flags); ret = clocksource_enqueue(c); if (!ret) @@ -512,6 +509,18 @@ static ssize_t sysfs_override_clocksource(struct sys_device *dev, } } + /* + * Check to make sure we don't switch to a non-highres capable + * clocksource if the tick code is in oneshot mode (highres or nohz) + */ + if (tick_oneshot_mode_active() && + !(ovr->flags & CLOCK_SOURCE_VALID_FOR_HRES)) { + printk(KERN_WARNING "%s clocksource is not HRT compatible. " + "Cannot switch while in HRT/NOHZ mode\n", ovr->name); + ovr = NULL; + override_name[0] = 0; + } + /* Reselect, when the override name has changed */ if (ovr != clocksource_override) { clocksource_override = ovr; @@ -540,7 +549,13 @@ sysfs_show_available_clocksources(struct sys_device *dev, spin_lock_irq(&clocksource_lock); list_for_each_entry(src, &clocksource_list, list) { - count += snprintf(buf + count, + /* + * Don't show non-HRES clocksource if the tick code is + * in one shot mode (highres=on or nohz=on) + */ + if (!tick_oneshot_mode_active() || + (src->flags & CLOCK_SOURCE_VALID_FOR_HRES)) + count += snprintf(buf + count, max((ssize_t)PAGE_SIZE - count, (ssize_t)0), "%s ", src->name); } diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c index 118a3b3b3f9..877dbedc311 100644 --- a/kernel/time/tick-broadcast.c +++ b/kernel/time/tick-broadcast.c @@ -27,7 +27,7 @@ * timer stops in C3 state. */ -struct tick_device tick_broadcast_device; +static struct tick_device tick_broadcast_device; /* FIXME: Use cpumask_var_t. */ static DECLARE_BITMAP(tick_broadcast_mask, NR_CPUS); static DECLARE_BITMAP(tmpmask, NR_CPUS); diff --git a/kernel/time/tick-common.c b/kernel/time/tick-common.c index 21a5ca84951..83c4417b6a3 100644 --- a/kernel/time/tick-common.c +++ b/kernel/time/tick-common.c @@ -93,7 +93,17 @@ void tick_handle_periodic(struct clock_event_device *dev) for (;;) { if (!clockevents_program_event(dev, next, ktime_get())) return; - tick_periodic(cpu); + /* + * Have to be careful here. If we're in oneshot mode, + * before we call tick_periodic() in a loop, we need + * to be sure we're using a real hardware clocksource. + * Otherwise we could get trapped in an infinite + * loop, as the tick_periodic() increments jiffies, + * when then will increment time, posibly causing + * the loop to trigger again and again. + */ + if (timekeeping_valid_for_hres()) + tick_periodic(cpu); next = ktime_add(next, tick_period); } } diff --git a/kernel/time/tick-oneshot.c b/kernel/time/tick-oneshot.c index 2e8de678e76..a96c0e2b89c 100644 --- a/kernel/time/tick-oneshot.c +++ b/kernel/time/tick-oneshot.c @@ -128,6 +128,23 @@ int tick_switch_to_oneshot(void (*handler)(struct clock_event_device *)) return 0; } +/** + * tick_check_oneshot_mode - check whether the system is in oneshot mode + * + * returns 1 when either nohz or highres are enabled. otherwise 0. + */ +int tick_oneshot_mode_active(void) +{ + unsigned long flags; + int ret; + + local_irq_save(flags); + ret = __get_cpu_var(tick_cpu_device).mode == TICKDEV_MODE_ONESHOT; + local_irq_restore(flags); + + return ret; +} + #ifdef CONFIG_HIGH_RES_TIMERS /** * tick_init_highres - switch to high resolution mode diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 687dff49f6e..e8c77d9c633 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -22,7 +22,7 @@ /* * This read-write spinlock protects us from races in SMP while - * playing with xtime and avenrun. + * playing with xtime. */ __cacheline_aligned_in_smp DEFINE_SEQLOCK(xtime_lock); @@ -77,6 +77,10 @@ static void clocksource_forward_now(void) clock->cycle_last = cycle_now; nsec = cyc2ns(clock, cycle_delta); + + /* If arch requires, add in gettimeoffset() */ + nsec += arch_gettimeoffset(); + timespec_add_ns(&xtime, nsec); nsec = ((s64)cycle_delta * clock->mult_orig) >> clock->shift; @@ -111,6 +115,9 @@ void getnstimeofday(struct timespec *ts) /* convert to nanoseconds: */ nsecs = cyc2ns(clock, cycle_delta); + /* If arch requires, add in gettimeoffset() */ + nsecs += arch_gettimeoffset(); + } while (read_seqretry(&xtime_lock, seq)); timespec_add_ns(ts, nsecs); |