diff options
| author | Thomas Gleixner <tglx@linutronix.de> | 2008-01-30 13:30:02 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2008-01-30 13:30:02 +0100 |
| commit | 4713e22ce81eb8b3353e16435362eb3d0ec95640 (patch) | |
| tree | 6f96151bd9b182d6b9d706d3ad3b4fe8c99e7f7e | |
| parent | 316da3b3fc8efa9a5d2c99e0d449f01ff38c6aba (diff) | |
| download | lwn-4713e22ce81eb8b3353e16435362eb3d0ec95640.tar.gz lwn-4713e22ce81eb8b3353e16435362eb3d0ec95640.zip | |
clocksource: add unregister function to disable unusable clocksources
On x86 the PIT might become an unusable clocksource. Add an unregister
function to provide a possibilty to remove the PIT from the list of
available clock sources.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
| -rw-r--r-- | arch/x86/kernel/i8253.c | 1 | ||||
| -rw-r--r-- | include/linux/clocksource.h | 1 | ||||
| -rw-r--r-- | kernel/time/clocksource.c | 15 |
3 files changed, 17 insertions, 0 deletions
diff --git a/arch/x86/kernel/i8253.c b/arch/x86/kernel/i8253.c index 0f8f35458a8f..decc5d294d76 100644 --- a/arch/x86/kernel/i8253.c +++ b/arch/x86/kernel/i8253.c @@ -13,6 +13,7 @@ #include <asm/delay.h> #include <asm/i8253.h> #include <asm/io.h> +#include <asm/hpet.h> DEFINE_SPINLOCK(i8253_lock); EXPORT_SYMBOL(i8253_lock); diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h index 07b42153de24..85778a4b1209 100644 --- a/include/linux/clocksource.h +++ b/include/linux/clocksource.h @@ -215,6 +215,7 @@ static inline void clocksource_calculate_interval(struct clocksource *c, /* used to install a new clocksource */ extern int clocksource_register(struct clocksource*); +extern void clocksource_unregister(struct clocksource*); extern struct clocksource* clocksource_get_next(void); extern void clocksource_change_rating(struct clocksource *cs, int rating); extern void clocksource_resume(void); diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c index edd5ef8e1765..6e9259a5d501 100644 --- a/kernel/time/clocksource.c +++ b/kernel/time/clocksource.c @@ -337,6 +337,21 @@ void clocksource_change_rating(struct clocksource *cs, int rating) spin_unlock_irqrestore(&clocksource_lock, flags); } +/** + * clocksource_unregister - remove a registered clocksource + */ +void clocksource_unregister(struct clocksource *cs) +{ + unsigned long flags; + + spin_lock_irqsave(&clocksource_lock, flags); + list_del(&cs->list); + if (clocksource_override == cs) + clocksource_override = NULL; + next_clocksource = select_clocksource(); + spin_unlock_irqrestore(&clocksource_lock, flags); +} + #ifdef CONFIG_SYSFS /** * sysfs_show_current_clocksources - sysfs interface for current clocksource |