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authorLinus Torvalds <torvalds@linux-foundation.org>2011-01-06 19:42:43 +0100
committerLinus Torvalds <torvalds@linux-foundation.org>2011-01-06 19:42:43 +0100
commitdda5f0a372873bca5f0b1d1866d7784dffd8b675 (patch)
tree1f745951b51ef9dcd127ca3c65ecb1d2ce4967c2 /kernel/timer.c
parentMerge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/ker... (diff)
parentMAINTAINERS: Update timer related entries (diff)
downloadlinux-dda5f0a372873bca5f0b1d1866d7784dffd8b675.tar.xz
linux-dda5f0a372873bca5f0b1d1866d7784dffd8b675.zip
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: MAINTAINERS: Update timer related entries timers: Use this_cpu_read timerqueue: Make timerqueue_getnext() static inline hrtimer: fix timerqueue conversion flub hrtimers: Convert hrtimers to use timerlist infrastructure timers: Fixup allmodconfig build issue timers: Rename timerlist infrastructure to timerqueue timers: Introduce timerlist infrastructure. hrtimer: Remove stale comment on curr_timer timer: Warn when del_timer_sync() is called in hardirq context timer: Del_timer_sync() can be used in softirq context timer: Make try_to_del_timer_sync() the same on SMP and UP posix-timers: Annotate lock_timer() timer: Permit statically-declared work with deferrable timers time: Use ARRAY_SIZE macro in timecompare.c timer: Initialize the field slack of timer_list timer_list: Remove alignment padding on 64 bit when CONFIG_TIMER_STATS time: Compensate for rounding on odd-frequency clocksources Fix up trivial conflict in MAINTAINERS
Diffstat (limited to 'kernel/timer.c')
-rw-r--r--kernel/timer.c50
1 files changed, 14 insertions, 36 deletions
diff --git a/kernel/timer.c b/kernel/timer.c
index 353b9227c2ec..43ca9936f2d0 100644
--- a/kernel/timer.c
+++ b/kernel/timer.c
@@ -88,18 +88,6 @@ struct tvec_base boot_tvec_bases;
EXPORT_SYMBOL(boot_tvec_bases);
static DEFINE_PER_CPU(struct tvec_base *, tvec_bases) = &boot_tvec_bases;
-/*
- * Note that all tvec_bases are 2 byte aligned and lower bit of
- * base in timer_list is guaranteed to be zero. Use the LSB to
- * indicate whether the timer is deferrable.
- *
- * A deferrable timer will work normally when the system is busy, but
- * will not cause a CPU to come out of idle just to service it; instead,
- * the timer will be serviced when the CPU eventually wakes up with a
- * subsequent non-deferrable timer.
- */
-#define TBASE_DEFERRABLE_FLAG (0x1)
-
/* Functions below help us manage 'deferrable' flag */
static inline unsigned int tbase_get_deferrable(struct tvec_base *base)
{
@@ -113,8 +101,7 @@ static inline struct tvec_base *tbase_get_base(struct tvec_base *base)
static inline void timer_set_deferrable(struct timer_list *timer)
{
- timer->base = ((struct tvec_base *)((unsigned long)(timer->base) |
- TBASE_DEFERRABLE_FLAG));
+ timer->base = TBASE_MAKE_DEFERRED(timer->base);
}
static inline void
@@ -343,15 +330,6 @@ void set_timer_slack(struct timer_list *timer, int slack_hz)
}
EXPORT_SYMBOL_GPL(set_timer_slack);
-
-static inline void set_running_timer(struct tvec_base *base,
- struct timer_list *timer)
-{
-#ifdef CONFIG_SMP
- base->running_timer = timer;
-#endif
-}
-
static void internal_add_timer(struct tvec_base *base, struct timer_list *timer)
{
unsigned long expires = timer->expires;
@@ -936,15 +914,12 @@ int del_timer(struct timer_list *timer)
}
EXPORT_SYMBOL(del_timer);
-#ifdef CONFIG_SMP
/**
* try_to_del_timer_sync - Try to deactivate a timer
* @timer: timer do del
*
* This function tries to deactivate a timer. Upon successful (ret >= 0)
* exit the timer is not queued and the handler is not running on any CPU.
- *
- * It must not be called from interrupt contexts.
*/
int try_to_del_timer_sync(struct timer_list *timer)
{
@@ -973,6 +948,7 @@ out:
}
EXPORT_SYMBOL(try_to_del_timer_sync);
+#ifdef CONFIG_SMP
/**
* del_timer_sync - deactivate a timer and wait for the handler to finish.
* @timer: the timer to be deactivated
@@ -983,7 +959,7 @@ EXPORT_SYMBOL(try_to_del_timer_sync);
*
* Synchronization rules: Callers must prevent restarting of the timer,
* otherwise this function is meaningless. It must not be called from
- * interrupt contexts. The caller must not hold locks which would prevent
+ * hardirq contexts. The caller must not hold locks which would prevent
* completion of the timer's handler. The timer's handler must not call
* add_timer_on(). Upon exit the timer is not queued and the handler is
* not running on any CPU.
@@ -993,14 +969,16 @@ EXPORT_SYMBOL(try_to_del_timer_sync);
int del_timer_sync(struct timer_list *timer)
{
#ifdef CONFIG_LOCKDEP
- unsigned long flags;
-
- local_irq_save(flags);
+ local_bh_disable();
lock_map_acquire(&timer->lockdep_map);
lock_map_release(&timer->lockdep_map);
- local_irq_restore(flags);
+ local_bh_enable();
#endif
-
+ /*
+ * don't use it in hardirq context, because it
+ * could lead to deadlock.
+ */
+ WARN_ON(in_irq());
for (;;) {
int ret = try_to_del_timer_sync(timer);
if (ret >= 0)
@@ -1111,7 +1089,7 @@ static inline void __run_timers(struct tvec_base *base)
timer_stats_account_timer(timer);
- set_running_timer(base, timer);
+ base->running_timer = timer;
detach_timer(timer, 1);
spin_unlock_irq(&base->lock);
@@ -1119,7 +1097,7 @@ static inline void __run_timers(struct tvec_base *base)
spin_lock_irq(&base->lock);
}
}
- set_running_timer(base, NULL);
+ base->running_timer = NULL;
spin_unlock_irq(&base->lock);
}
@@ -1249,7 +1227,7 @@ static unsigned long cmp_next_hrtimer_event(unsigned long now,
*/
unsigned long get_next_timer_interrupt(unsigned long now)
{
- struct tvec_base *base = __get_cpu_var(tvec_bases);
+ struct tvec_base *base = __this_cpu_read(tvec_bases);
unsigned long expires;
/*
@@ -1298,7 +1276,7 @@ void update_process_times(int user_tick)
*/
static void run_timer_softirq(struct softirq_action *h)
{
- struct tvec_base *base = __get_cpu_var(tvec_bases);
+ struct tvec_base *base = __this_cpu_read(tvec_bases);
hrtimer_run_pending();