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:
  hrtimer: Eliminate needless reprogramming of clock events device
This commit is contained in:
Linus Torvalds 2009-09-27 10:39:04 -07:00
commit 6f5071020d

View file

@ -509,13 +509,14 @@ static inline int hrtimer_hres_active(void)
* next event
* Called with interrupts disabled and base->lock held
*/
static void hrtimer_force_reprogram(struct hrtimer_cpu_base *cpu_base)
static void
hrtimer_force_reprogram(struct hrtimer_cpu_base *cpu_base, int skip_equal)
{
int i;
struct hrtimer_clock_base *base = cpu_base->clock_base;
ktime_t expires;
ktime_t expires, expires_next;
cpu_base->expires_next.tv64 = KTIME_MAX;
expires_next.tv64 = KTIME_MAX;
for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++, base++) {
struct hrtimer *timer;
@ -531,10 +532,15 @@ static void hrtimer_force_reprogram(struct hrtimer_cpu_base *cpu_base)
*/
if (expires.tv64 < 0)
expires.tv64 = 0;
if (expires.tv64 < cpu_base->expires_next.tv64)
cpu_base->expires_next = expires;
if (expires.tv64 < expires_next.tv64)
expires_next = expires;
}
if (skip_equal && expires_next.tv64 == cpu_base->expires_next.tv64)
return;
cpu_base->expires_next.tv64 = expires_next.tv64;
if (cpu_base->expires_next.tv64 != KTIME_MAX)
tick_program_event(cpu_base->expires_next, 1);
}
@ -617,7 +623,7 @@ static void retrigger_next_event(void *arg)
base->clock_base[CLOCK_REALTIME].offset =
timespec_to_ktime(realtime_offset);
hrtimer_force_reprogram(base);
hrtimer_force_reprogram(base, 0);
spin_unlock(&base->lock);
}
@ -730,7 +736,8 @@ static int hrtimer_switch_to_hres(void)
static inline int hrtimer_hres_active(void) { return 0; }
static inline int hrtimer_is_hres_enabled(void) { return 0; }
static inline int hrtimer_switch_to_hres(void) { return 0; }
static inline void hrtimer_force_reprogram(struct hrtimer_cpu_base *base) { }
static inline void
hrtimer_force_reprogram(struct hrtimer_cpu_base *base, int skip_equal) { }
static inline int hrtimer_enqueue_reprogram(struct hrtimer *timer,
struct hrtimer_clock_base *base,
int wakeup)
@ -873,19 +880,29 @@ static void __remove_hrtimer(struct hrtimer *timer,
struct hrtimer_clock_base *base,
unsigned long newstate, int reprogram)
{
if (timer->state & HRTIMER_STATE_ENQUEUED) {
/*
* Remove the timer from the rbtree and replace the
* first entry pointer if necessary.
*/
if (base->first == &timer->node) {
base->first = rb_next(&timer->node);
/* Reprogram the clock event device. if enabled */
if (reprogram && hrtimer_hres_active())
hrtimer_force_reprogram(base->cpu_base);
if (!(timer->state & HRTIMER_STATE_ENQUEUED))
goto out;
/*
* Remove the timer from the rbtree and replace the first
* entry pointer if necessary.
*/
if (base->first == &timer->node) {
base->first = rb_next(&timer->node);
#ifdef CONFIG_HIGH_RES_TIMERS
/* Reprogram the clock event device. if enabled */
if (reprogram && hrtimer_hres_active()) {
ktime_t expires;
expires = ktime_sub(hrtimer_get_expires(timer),
base->offset);
if (base->cpu_base->expires_next.tv64 == expires.tv64)
hrtimer_force_reprogram(base->cpu_base, 1);
}
rb_erase(&timer->node, &base->active);
#endif
}
rb_erase(&timer->node, &base->active);
out:
timer->state = newstate;
}