Skip to content

Commit

Permalink
hrtimers: Convert hrtimers to use timerlist infrastructure
Browse files Browse the repository at this point in the history 
Converts the hrtimer code to use the new timerlist infrastructure

Signed-off-by: John Stultz <john.stultz@linaro.org>
LKML Reference: <1290136329-18291-3-git-send-email-john.stultz@linaro.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
CC: Alessandro Zummo <a.zummo@towertech.it>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Richard Cochran <richardcochran@gmail.com>
  • Loading branch information
John Stultz committed Dec 10, 2010
1 parent 9bb99b1 commit 998adc3
Show file tree
Hide file tree
Showing 3 changed files with 49 additions and 77 deletions.
32 changes: 15 additions & 17 deletions include/linux/hrtimer.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -22,7 +22,7 @@
#include <linux/wait.h>
#include <linux/percpu.h>
#include <linux/timer.h>

#include <linux/timerqueue.h>

struct hrtimer_clock_base;
struct hrtimer_cpu_base;
Expand Down Expand Up @@ -79,8 +79,8 @@ enum hrtimer_restart {

/**
* struct hrtimer - the basic hrtimer structure
* @node: red black tree node for time ordered insertion
* @_expires: the absolute expiry time in the hrtimers internal
* @node: timerqueue node, which also manages node.expires,
* the absolute expiry time in the hrtimers internal
* representation. The time is related to the clock on
* which the timer is based. Is setup by adding
* slack to the _softexpires value. For non range timers
Expand All @@ -101,8 +101,7 @@ enum hrtimer_restart {
* The hrtimer structure must be initialized by hrtimer_init()
*/
struct hrtimer {
struct rb_node node;
ktime_t _expires;
struct timerqueue_node node;
ktime_t _softexpires;
enum hrtimer_restart (*function)(struct hrtimer *);
struct hrtimer_clock_base *base;
Expand Down Expand Up @@ -141,8 +140,7 @@ struct hrtimer_sleeper {
struct hrtimer_clock_base {
struct hrtimer_cpu_base *cpu_base;
clockid_t index;
struct rb_root active;
struct rb_node *first;
struct timerqueue_head active;
ktime_t resolution;
ktime_t (*get_time)(void);
ktime_t softirq_time;
Expand Down Expand Up @@ -183,43 +181,43 @@ struct hrtimer_cpu_base {

static inline void hrtimer_set_expires(struct hrtimer *timer, ktime_t time)
{
timer->_expires = time;
timer->node.expires = time;
timer->_softexpires = time;
}

static inline void hrtimer_set_expires_range(struct hrtimer *timer, ktime_t time, ktime_t delta)
{
timer->_softexpires = time;
timer->_expires = ktime_add_safe(time, delta);
timer->node.expires = ktime_add_safe(time, delta);
}

static inline void hrtimer_set_expires_range_ns(struct hrtimer *timer, ktime_t time, unsigned long delta)
{
timer->_softexpires = time;
timer->_expires = ktime_add_safe(time, ns_to_ktime(delta));
timer->node.expires = ktime_add_safe(time, ns_to_ktime(delta));
}

static inline void hrtimer_set_expires_tv64(struct hrtimer *timer, s64 tv64)
{
timer->_expires.tv64 = tv64;
timer->node.expires.tv64 = tv64;
timer->_softexpires.tv64 = tv64;
}

static inline void hrtimer_add_expires(struct hrtimer *timer, ktime_t time)
{
timer->_expires = ktime_add_safe(timer->_expires, time);
timer->node.expires = ktime_add_safe(timer->node.expires, time);
timer->_softexpires = ktime_add_safe(timer->_softexpires, time);
}

static inline void hrtimer_add_expires_ns(struct hrtimer *timer, u64 ns)
{
timer->_expires = ktime_add_ns(timer->_expires, ns);
timer->node.expires = ktime_add_ns(timer->node.expires, ns);
timer->_softexpires = ktime_add_ns(timer->_softexpires, ns);
}

static inline ktime_t hrtimer_get_expires(const struct hrtimer *timer)
{
return timer->_expires;
return timer->node.expires;
}

static inline ktime_t hrtimer_get_softexpires(const struct hrtimer *timer)
Expand All @@ -229,7 +227,7 @@ static inline ktime_t hrtimer_get_softexpires(const struct hrtimer *timer)

static inline s64 hrtimer_get_expires_tv64(const struct hrtimer *timer)
{
return timer->_expires.tv64;
return timer->node.expires.tv64;
}
static inline s64 hrtimer_get_softexpires_tv64(const struct hrtimer *timer)
{
Expand All @@ -238,12 +236,12 @@ static inline s64 hrtimer_get_softexpires_tv64(const struct hrtimer *timer)

static inline s64 hrtimer_get_expires_ns(const struct hrtimer *timer)
{
return ktime_to_ns(timer->_expires);
return ktime_to_ns(timer->node.expires);
}

static inline ktime_t hrtimer_expires_remaining(const struct hrtimer *timer)
{
return ktime_sub(timer->_expires, timer->base->get_time());
return ktime_sub(timer->node.expires, timer->base->get_time());
}

#ifdef CONFIG_HIGH_RES_TIMERS
Expand Down
86 changes: 30 additions & 56 deletions kernel/hrtimer.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -516,10 +516,13 @@ hrtimer_force_reprogram(struct hrtimer_cpu_base *cpu_base, int skip_equal)

for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++, base++) {
struct hrtimer *timer;
struct timerqueue_node *next;

if (!base->first)
next = timerqueue_getnext(&base->active);
if (!next)
continue;
timer = rb_entry(base->first, struct hrtimer, node);
timer = container_of(next, struct hrtimer, node);

expires = ktime_sub(hrtimer_get_expires(timer), base->offset);
/*
* clock_was_set() has changed base->offset so the
Expand Down Expand Up @@ -840,48 +843,17 @@ EXPORT_SYMBOL_GPL(hrtimer_forward);
static int enqueue_hrtimer(struct hrtimer *timer,
struct hrtimer_clock_base *base)
{
struct rb_node **link = &base->active.rb_node;
struct rb_node *parent = NULL;
struct hrtimer *entry;
int leftmost = 1;

debug_activate(timer);

/*
* Find the right place in the rbtree:
*/
while (*link) {
parent = *link;
entry = rb_entry(parent, struct hrtimer, node);
/*
* We dont care about collisions. Nodes with
* the same expiry time stay together.
*/
if (hrtimer_get_expires_tv64(timer) <
hrtimer_get_expires_tv64(entry)) {
link = &(*link)->rb_left;
} else {
link = &(*link)->rb_right;
leftmost = 0;
}
}
timerqueue_add(&base->active, &timer->node);

/*
* Insert the timer to the rbtree and check whether it
* replaces the first pending timer
*/
if (leftmost)
base->first = &timer->node;

rb_link_node(&timer->node, parent, link);
rb_insert_color(&timer->node, &base->active);
/*
* HRTIMER_STATE_ENQUEUED is or'ed to the current state to preserve the
* state of a possibly running callback.
*/
timer->state |= HRTIMER_STATE_ENQUEUED;

return leftmost;
return (&timer->node == base->active.next);
}

/*
Expand All @@ -901,12 +873,7 @@ static void __remove_hrtimer(struct hrtimer *timer,
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);
if (&timer->node == timerqueue_getnext(&base->active)) {
#ifdef CONFIG_HIGH_RES_TIMERS
/* Reprogram the clock event device. if enabled */
if (reprogram && hrtimer_hres_active()) {
Expand All @@ -919,7 +886,7 @@ static void __remove_hrtimer(struct hrtimer *timer,
}
#endif
}
rb_erase(&timer->node, &base->active);
timerqueue_del(&base->active, &timer->node);
out:
timer->state = newstate;
}
Expand Down Expand Up @@ -1123,11 +1090,13 @@ ktime_t hrtimer_get_next_event(void)
if (!hrtimer_hres_active()) {
for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++, base++) {
struct hrtimer *timer;
struct timerqueue_node *next;

if (!base->first)
next = timerqueue_getnext(&base->active);
if (!next)
continue;

timer = rb_entry(base->first, struct hrtimer, node);
timer = container_of(next, struct hrtimer, node);
delta.tv64 = hrtimer_get_expires_tv64(timer);
delta = ktime_sub(delta, base->get_time());
if (delta.tv64 < mindelta.tv64)
Expand Down Expand Up @@ -1157,6 +1126,7 @@ static void __hrtimer_init(struct hrtimer *timer, clockid_t clock_id,

timer->base = &cpu_base->clock_base[clock_id];
hrtimer_init_timer_hres(timer);
timerqueue_init(&timer->node);

#ifdef CONFIG_TIMER_STATS
timer->start_site = NULL;
Expand Down Expand Up @@ -1270,14 +1240,14 @@ void hrtimer_interrupt(struct clock_event_device *dev)

for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++) {
ktime_t basenow;
struct rb_node *node;
struct timerqueue_node *node;

basenow = ktime_add(now, base->offset);

while ((node = base->first)) {
while ((node = timerqueue_getnext(&base->active))) {
struct hrtimer *timer;

timer = rb_entry(node, struct hrtimer, node);
timer = container_of(node, struct hrtimer, node);

/*
* The immediate goal for using the softexpires is
Expand Down Expand Up @@ -1433,7 +1403,7 @@ void hrtimer_run_pending(void)
*/
void hrtimer_run_queues(void)
{
struct rb_node *node;
struct timerqueue_node *node;
struct hrtimer_cpu_base *cpu_base = &__get_cpu_var(hrtimer_bases);
struct hrtimer_clock_base *base;
int index, gettime = 1;
Expand All @@ -1442,9 +1412,11 @@ void hrtimer_run_queues(void)
return;

for (index = 0; index < HRTIMER_MAX_CLOCK_BASES; index++) {
base = &cpu_base->clock_base[index];
struct timerqueue_node *next;

if (!base->first)
base = &cpu_base->clock_base[index];
next = timerqueue_getnext(&base->active);
if (!next)
continue;

if (gettime) {
Expand All @@ -1454,10 +1426,10 @@ void hrtimer_run_queues(void)

raw_spin_lock(&cpu_base->lock);

while ((node = base->first)) {
while ((node = next)) {
struct hrtimer *timer;

timer = rb_entry(node, struct hrtimer, node);
timer = container_of(node, struct hrtimer, node);
if (base->softirq_time.tv64 <=
hrtimer_get_expires_tv64(timer))
break;
Expand Down Expand Up @@ -1622,8 +1594,10 @@ static void __cpuinit init_hrtimers_cpu(int cpu)

raw_spin_lock_init(&cpu_base->lock);

for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++)
for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++) {
cpu_base->clock_base[i].cpu_base = cpu_base;
timerqueue_init_head(&cpu_base->clock_base[i].active);
}

hrtimer_init_hres(cpu_base);
}
Expand All @@ -1634,10 +1608,10 @@ static void migrate_hrtimer_list(struct hrtimer_clock_base *old_base,
struct hrtimer_clock_base *new_base)
{
struct hrtimer *timer;
struct rb_node *node;
struct timerqueue_node *node;

while ((node = rb_first(&old_base->active))) {
timer = rb_entry(node, struct hrtimer, node);
while ((node = timerqueue_getnext(&old_base->active))) {
timer = container_of(node, struct hrtimer, node);
BUG_ON(hrtimer_callback_running(timer));
debug_deactivate(timer);

Expand Down
8 changes: 4 additions & 4 deletions kernel/time/timer_list.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -79,26 +79,26 @@ print_active_timers(struct seq_file *m, struct hrtimer_clock_base *base,
{
struct hrtimer *timer, tmp;
unsigned long next = 0, i;
struct rb_node *curr;
struct timerqueue_node *curr;
unsigned long flags;

next_one:
i = 0;
raw_spin_lock_irqsave(&base->cpu_base->lock, flags);

curr = base->first;
curr = timerqueue_getnext(&base->active);
/*
* Crude but we have to do this O(N*N) thing, because
* we have to unlock the base when printing:
*/
while (curr && i < next) {
curr = rb_next(curr);
curr = timerqueue_iterate_next(curr);
i++;
}

if (curr) {

timer = rb_entry(curr, struct hrtimer, node);
timer = container_of(curr, struct hrtimer, node);
tmp = *timer;
raw_spin_unlock_irqrestore(&base->cpu_base->lock, flags);

Expand Down

0 comments on commit 998adc3

Please sign in to comment.