diff options
| author | Thomas Gleixner <tglx@linutronix.de> | 2007-02-16 01:27:47 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-02-16 08:13:58 -0800 |
| commit | fd064b9b7770d5c7705bf9542950c7bd81c30f98 (patch) | |
| tree | 8b14c81f983e49b5553fd6764139bffb1d4f1648 /kernel/timer.c | |
| parent | 1cfd68496e53f7be09a3c1358d1d389004217541 (diff) | |
| download | lwn-fd064b9b7770d5c7705bf9542950c7bd81c30f98.tar.gz lwn-fd064b9b7770d5c7705bf9542950c7bd81c30f98.zip | |
[PATCH] Extend next_timer_interrupt() to use a reference jiffie
For CONFIG_NO_HZ we need to calculate the next timer wheel event based on a
given jiffie value. Extend the existing code to allow the extra 'now'
argument. Provide a compability function for the existing implementations to
call the function with now == jiffies. (This also solves the racyness of the
original code vs. jiffies changing during the iteration.)
No functional changes to existing users of this infrastructure.
[ remove WARN_ON() that triggered on s390, by Carsten Otte <cotte@de.ibm.com> ]
[ made new helper static, Adrian Bunk <bunk@stusta.de> ]
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'kernel/timer.c')
| -rw-r--r-- | kernel/timer.c | 14 |
1 files changed, 11 insertions, 3 deletions
diff --git a/kernel/timer.c b/kernel/timer.c index 201bee07b8e0..6d843e100e75 100644 --- a/kernel/timer.c +++ b/kernel/timer.c @@ -591,7 +591,7 @@ static inline void __run_timers(tvec_base_t *base) spin_unlock_irq(&base->lock); } -#ifdef CONFIG_NO_IDLE_HZ +#if defined(CONFIG_NO_IDLE_HZ) || defined(CONFIG_NO_HZ) /* * Find out when the next timer event is due to happen. This * is used on S/390 to stop all activity when a cpus is idle. @@ -687,10 +687,10 @@ static unsigned long cmp_next_hrtimer_event(unsigned long now, /** * next_timer_interrupt - return the jiffy of the next pending timer */ -unsigned long next_timer_interrupt(void) +unsigned long get_next_timer_interrupt(unsigned long now) { tvec_base_t *base = __get_cpu_var(tvec_bases); - unsigned long expires, now = jiffies; + unsigned long expires; spin_lock(&base->lock); expires = __next_timer_interrupt(base); @@ -701,6 +701,14 @@ unsigned long next_timer_interrupt(void) return cmp_next_hrtimer_event(now, expires); } + +#ifdef CONFIG_NO_IDLE_HZ +unsigned long next_timer_interrupt(void) +{ + return get_next_timer_interrupt(jiffies); +} +#endif + #endif /******************************************************************/ |