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-rw-r--r--MAINTAINERS16
-rw-r--r--include/linux/hrtimer.h33
-rw-r--r--include/linux/timer.h32
-rw-r--r--include/linux/timerqueue.h50
-rw-r--r--include/linux/workqueue.h8
-rw-r--r--kernel/hrtimer.c83
-rw-r--r--kernel/posix-timers.c10
-rw-r--r--kernel/time/timecompare.c5
-rw-r--r--kernel/time/timekeeping.c9
-rw-r--r--kernel/time/timer_list.c8
-rw-r--r--kernel/timer.c50
-rw-r--r--lib/Makefile2
-rw-r--r--lib/timerqueue.c107
13 files changed, 289 insertions, 124 deletions
diff --git a/MAINTAINERS b/MAINTAINERS
index b1dda78a1e75..c5c7292daba0 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -2812,6 +2812,10 @@ M: Thomas Gleixner <tglx@linutronix.de>
S: Maintained
F: Documentation/timers/
F: kernel/hrtimer.c
+F: kernel/time/clockevents.c
+F: kernel/time/tick*.*
+F: kernel/time/timer_*.c
+F include/linux/clockevents.h
F: include/linux/hrtimer.h
HIGH-SPEED SCC DRIVER FOR AX.25
@@ -5142,6 +5146,18 @@ L: alsa-devel@alsa-project.org (moderated for non-subscribers)
S: Supported
F: sound/soc/s3c24xx
+TIMEKEEPING, NTP
+M: John Stultz <johnstul@us.ibm.com>
+M: Thomas Gleixner <tglx@linutronix.de>
+S: Supported
+F: include/linux/clocksource.h
+F: include/linux/time.h
+F: include/linux/timex.h
+F: include/linux/timekeeping.h
+F: kernel/time/clocksource.c
+F: kernel/time/time*.c
+F: kernel/time/ntp.c
+
TLG2300 VIDEO4LINUX-2 DRIVER
M: Huang Shijie <shijie8@gmail.com>
M: Kang Yong <kangyong@telegent.com>
diff --git a/include/linux/hrtimer.h b/include/linux/hrtimer.h
index fd0c1b857d3d..330586ffffbb 100644
--- a/include/linux/hrtimer.h
+++ b/include/linux/hrtimer.h
@@ -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;
@@ -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
@@ -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;
@@ -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;
@@ -158,7 +156,6 @@ struct hrtimer_clock_base {
* @lock: lock protecting the base and associated clock bases
* and timers
* @clock_base: array of clock bases for this cpu
- * @curr_timer: the timer which is executing a callback right now
* @expires_next: absolute time of the next event which was scheduled
* via clock_set_next_event()
* @hres_active: State of high resolution mode
@@ -184,43 +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)
@@ -230,7 +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)
{
@@ -239,12 +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
diff --git a/include/linux/timer.h b/include/linux/timer.h
index 38cf093ef62c..6abd9138beda 100644
--- a/include/linux/timer.h
+++ b/include/linux/timer.h
@@ -24,9 +24,9 @@ struct timer_list {
int slack;
#ifdef CONFIG_TIMER_STATS
+ int start_pid;
void *start_site;
char start_comm[16];
- int start_pid;
#endif
#ifdef CONFIG_LOCKDEP
struct lockdep_map lockdep_map;
@@ -48,12 +48,38 @@ extern struct tvec_base boot_tvec_bases;
#define __TIMER_LOCKDEP_MAP_INITIALIZER(_kn)
#endif
+/*
+ * 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)
+
#define TIMER_INITIALIZER(_function, _expires, _data) { \
.entry = { .prev = TIMER_ENTRY_STATIC }, \
.function = (_function), \
.expires = (_expires), \
.data = (_data), \
.base = &boot_tvec_bases, \
+ .slack = -1, \
+ __TIMER_LOCKDEP_MAP_INITIALIZER( \
+ __FILE__ ":" __stringify(__LINE__)) \
+ }
+
+#define TBASE_MAKE_DEFERRED(ptr) ((struct tvec_base *) \
+ ((unsigned char *)(ptr) + TBASE_DEFERRABLE_FLAG))
+
+#define TIMER_DEFERRED_INITIALIZER(_function, _expires, _data) {\
+ .entry = { .prev = TIMER_ENTRY_STATIC }, \
+ .function = (_function), \
+ .expires = (_expires), \
+ .data = (_data), \
+ .base = TBASE_MAKE_DEFERRED(&boot_tvec_bases), \
__TIMER_LOCKDEP_MAP_INITIALIZER( \
__FILE__ ":" __stringify(__LINE__)) \
}
@@ -248,11 +274,11 @@ static inline void timer_stats_timer_clear_start_info(struct timer_list *timer)
extern void add_timer(struct timer_list *timer);
+extern int try_to_del_timer_sync(struct timer_list *timer);
+
#ifdef CONFIG_SMP
- extern int try_to_del_timer_sync(struct timer_list *timer);
extern int del_timer_sync(struct timer_list *timer);
#else
-# define try_to_del_timer_sync(t) del_timer(t)
# define del_timer_sync(t) del_timer(t)
#endif
diff --git a/include/linux/timerqueue.h b/include/linux/timerqueue.h
new file mode 100644
index 000000000000..d24aabaca474
--- /dev/null
+++ b/include/linux/timerqueue.h
@@ -0,0 +1,50 @@
+#ifndef _LINUX_TIMERQUEUE_H
+#define _LINUX_TIMERQUEUE_H
+
+#include <linux/rbtree.h>
+#include <linux/ktime.h>
+
+
+struct timerqueue_node {
+ struct rb_node node;
+ ktime_t expires;
+};
+
+struct timerqueue_head {
+ struct rb_root head;
+ struct timerqueue_node *next;
+};
+
+
+extern void timerqueue_add(struct timerqueue_head *head,
+ struct timerqueue_node *node);
+extern void timerqueue_del(struct timerqueue_head *head,
+ struct timerqueue_node *node);
+extern struct timerqueue_node *timerqueue_iterate_next(
+ struct timerqueue_node *node);
+
+/**
+ * timerqueue_getnext - Returns the timer with the earlies expiration time
+ *
+ * @head: head of timerqueue
+ *
+ * Returns a pointer to the timer node that has the
+ * earliest expiration time.
+ */
+static inline
+struct timerqueue_node *timerqueue_getnext(struct timerqueue_head *head)
+{
+ return head->next;
+}
+
+static inline void timerqueue_init(struct timerqueue_node *node)
+{
+ RB_CLEAR_NODE(&node->node);
+}
+
+static inline void timerqueue_init_head(struct timerqueue_head *head)
+{
+ head->head = RB_ROOT;
+ head->next = NULL;
+}
+#endif /* _LINUX_TIMERQUEUE_H */
diff --git a/include/linux/workqueue.h b/include/linux/workqueue.h
index 0c0771f06bfa..bd257fee6031 100644
--- a/include/linux/workqueue.h
+++ b/include/linux/workqueue.h
@@ -127,12 +127,20 @@ struct execute_work {
.timer = TIMER_INITIALIZER(NULL, 0, 0), \
}
+#define __DEFERRED_WORK_INITIALIZER(n, f) { \
+ .work = __WORK_INITIALIZER((n).work, (f)), \
+ .timer = TIMER_DEFERRED_INITIALIZER(NULL, 0, 0), \
+ }
+
#define DECLARE_WORK(n, f) \
struct work_struct n = __WORK_INITIALIZER(n, f)
#define DECLARE_DELAYED_WORK(n, f) \
struct delayed_work n = __DELAYED_WORK_INITIALIZER(n, f)
+#define DECLARE_DEFERRED_WORK(n, f) \
+ struct delayed_work n = __DEFERRED_WORK_INITIALIZER(n, f)
+
/*
* initialize a work item's function pointer
*/
diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c
index 72206cf5c6cf..f2429fc3438c 100644
--- a/kernel/hrtimer.c
+++ b/kernel/hrtimer.c
@@ -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
@@ -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;
- }
- }
-
- /*
- * Insert the timer to the rbtree and check whether it
- * replaces the first pending timer
- */
- if (leftmost)
- base->first = &timer->node;
+ timerqueue_add(&base->active, &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);
}
/*
@@ -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()) {
@@ -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;
}
@@ -1128,11 +1095,13 @@ 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)
@@ -1162,6 +1131,7 @@ 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;
@@ -1278,14 +1248,14 @@ retry:
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
@@ -1441,7 +1411,7 @@ 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;
@@ -1451,8 +1421,7 @@ void hrtimer_run_queues(void)
for (index = 0; index < HRTIMER_MAX_CLOCK_BASES; index++) {
base = &cpu_base->clock_base[index];
-
- if (!base->first)
+ if (!timerqueue_getnext(&base->active))
continue;
if (gettime) {
@@ -1462,10 +1431,10 @@ void hrtimer_run_queues(void)
raw_spin_lock(&cpu_base->lock);
- 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);
if (base->softirq_time.tv64 <=
hrtimer_get_expires_tv64(timer))
break;
@@ -1630,8 +1599,10 @@ 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);
}
@@ -1642,10 +1613,10 @@ 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);
diff --git a/kernel/posix-timers.c b/kernel/posix-timers.c
index 9ca4973f736d..93bd2eb2bc53 100644
--- a/kernel/posix-timers.c
+++ b/kernel/posix-timers.c
@@ -145,7 +145,13 @@ static int common_timer_del(struct k_itimer *timer);
static enum hrtimer_restart posix_timer_fn(struct hrtimer *data);
-static struct k_itimer *lock_timer(timer_t timer_id, unsigned long *flags);
+static struct k_itimer *__lock_timer(timer_t timer_id, unsigned long *flags);
+
+#define lock_timer(tid, flags) \
+({ struct k_itimer *__timr; \
+ __cond_lock(&__timr->it_lock, __timr = __lock_timer(tid, flags)); \
+ __timr; \
+})
static inline void unlock_timer(struct k_itimer *timr, unsigned long flags)
{
@@ -619,7 +625,7 @@ out:
* the find to the timer lock. To avoid a dead lock, the timer id MUST
* be release with out holding the timer lock.
*/
-static struct k_itimer *lock_timer(timer_t timer_id, unsigned long *flags)
+static struct k_itimer *__lock_timer(timer_t timer_id, unsigned long *flags)
{
struct k_itimer *timr;
/*
diff --git a/kernel/time/timecompare.c b/kernel/time/timecompare.c
index ac38fbb176cc..a9ae369925ce 100644
--- a/kernel/time/timecompare.c
+++ b/kernel/time/timecompare.c
@@ -21,6 +21,7 @@
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/math64.h>
+#include <linux/kernel.h>
/*
* fixed point arithmetic scale factor for skew
@@ -57,11 +58,11 @@ int timecompare_offset(struct timecompare *sync,
int index;
int num_samples = sync->num_samples;
- if (num_samples > sizeof(buffer)/sizeof(buffer[0])) {
+ if (num_samples > ARRAY_SIZE(buffer)) {
samples = kmalloc(sizeof(*samples) * num_samples, GFP_ATOMIC);
if (!samples) {
samples = buffer;
- num_samples = sizeof(buffer)/sizeof(buffer[0]);
+ num_samples = ARRAY_SIZE(buffer);
}
} else {
samples = buffer;
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index 49010d822f72..5bb86da82003 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -32,6 +32,8 @@ struct timekeeper {
cycle_t cycle_interval;
/* Number of clock shifted nano seconds in one NTP interval. */
u64 xtime_interval;
+ /* shifted nano seconds left over when rounding cycle_interval */
+ s64 xtime_remainder;
/* Raw nano seconds accumulated per NTP interval. */
u32 raw_interval;
@@ -62,7 +64,7 @@ struct timekeeper timekeeper;
static void timekeeper_setup_internals(struct clocksource *clock)
{
cycle_t interval;
- u64 tmp;
+ u64 tmp, ntpinterval;
timekeeper.clock = clock;
clock->cycle_last = clock->read(clock);
@@ -70,6 +72,7 @@ static void timekeeper_setup_internals(struct clocksource *clock)
/* Do the ns -> cycle conversion first, using original mult */
tmp = NTP_INTERVAL_LENGTH;
tmp <<= clock->shift;
+ ntpinterval = tmp;
tmp += clock->mult/2;
do_div(tmp, clock->mult);
if (tmp == 0)
@@ -80,6 +83,7 @@ static void timekeeper_setup_internals(struct clocksource *clock)
/* Go back from cycles -> shifted ns */
timekeeper.xtime_interval = (u64) interval * clock->mult;
+ timekeeper.xtime_remainder = ntpinterval - timekeeper.xtime_interval;
timekeeper.raw_interval =
((u64) interval * clock->mult) >> clock->shift;
@@ -719,7 +723,8 @@ static cycle_t logarithmic_accumulation(cycle_t offset, int shift)
/* Accumulate error between NTP and clock interval */
timekeeper.ntp_error += tick_length << shift;
- timekeeper.ntp_error -= timekeeper.xtime_interval <<
+ timekeeper.ntp_error -=
+ (timekeeper.xtime_interval + timekeeper.xtime_remainder) <<
(timekeeper.ntp_error_shift + shift);
return offset;
diff --git a/kernel/time/timer_list.c b/kernel/time/timer_list.c
index ab8f5e33fa92..32a19f9397fc 100644
--- a/kernel/time/timer_list.c
+++ b/kernel/time/timer_list.c
@@ -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);
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();
diff --git a/lib/Makefile b/lib/Makefile
index e6a3763b8212..9e2db72d128e 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -8,7 +8,7 @@ KBUILD_CFLAGS = $(subst -pg,,$(ORIG_CFLAGS))
endif
lib-y := ctype.o string.o vsprintf.o cmdline.o \
- rbtree.o radix-tree.o dump_stack.o \
+ rbtree.o radix-tree.o dump_stack.o timerqueue.o\
idr.o int_sqrt.o extable.o prio_tree.o \
sha1.o irq_regs.o reciprocal_div.o argv_split.o \
proportions.o prio_heap.o ratelimit.o show_mem.o \
diff --git a/lib/timerqueue.c b/lib/timerqueue.c
new file mode 100644
index 000000000000..e3a1050e6820
--- /dev/null
+++ b/lib/timerqueue.c
@@ -0,0 +1,107 @@
+/*
+ * Generic Timer-queue
+ *
+ * Manages a simple queue of timers, ordered by expiration time.
+ * Uses rbtrees for quick list adds and expiration.
+ *
+ * NOTE: All of the following functions need to be serialized
+ * to avoid races. No locking is done by this libary code.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include <linux/timerqueue.h>
+#include <linux/rbtree.h>
+#include <linux/module.h>
+
+/**
+ * timerqueue_add - Adds timer to timerqueue.
+ *
+ * @head: head of timerqueue
+ * @node: timer node to be added
+ *
+ * Adds the timer node to the timerqueue, sorted by the
+ * node's expires value.
+ */
+void timerqueue_add(struct timerqueue_head *head, struct timerqueue_node *node)
+{
+ struct rb_node **p = &head->head.rb_node;
+ struct rb_node *parent = NULL;
+ struct timerqueue_node *ptr;
+
+ /* Make sure we don't add nodes that are already added */
+ WARN_ON_ONCE(!RB_EMPTY_NODE(&node->node));
+
+ while (*p) {
+ parent = *p;
+ ptr = rb_entry(parent, struct timerqueue_node, node);
+ if (node->expires.tv64 < ptr->expires.tv64)
+ p = &(*p)->rb_left;
+ else
+ p = &(*p)->rb_right;
+ }
+ rb_link_node(&node->node, parent, p);
+ rb_insert_color(&node->node, &head->head);
+
+ if (!head->next || node->expires.tv64 < head->next->expires.tv64)
+ head->next = node;
+}
+EXPORT_SYMBOL_GPL(timerqueue_add);
+
+/**
+ * timerqueue_del - Removes a timer from the timerqueue.
+ *
+ * @head: head of timerqueue
+ * @node: timer node to be removed
+ *
+ * Removes the timer node from the timerqueue.
+ */
+void timerqueue_del(struct timerqueue_head *head, struct timerqueue_node *node)
+{
+ WARN_ON_ONCE(RB_EMPTY_NODE(&node->node));
+
+ /* update next pointer */
+ if (head->next == node) {
+ struct rb_node *rbn = rb_next(&node->node);
+
+ head->next = rbn ?
+ rb_entry(rbn, struct timerqueue_node, node) : NULL;
+ }
+ rb_erase(&node->node, &head->head);
+ RB_CLEAR_NODE(&node->node);
+}
+EXPORT_SYMBOL_GPL(timerqueue_del);
+
+/**
+ * timerqueue_iterate_next - Returns the timer after the provided timer
+ *
+ * @node: Pointer to a timer.
+ *
+ * Provides the timer that is after the given node. This is used, when
+ * necessary, to iterate through the list of timers in a timer list
+ * without modifying the list.
+ */
+struct timerqueue_node *timerqueue_iterate_next(struct timerqueue_node *node)
+{
+ struct rb_node *next;
+
+ if (!node)
+ return NULL;
+ next = rb_next(&node->node);
+ if (!next)
+ return NULL;
+ return container_of(next, struct timerqueue_node, node);
+}
+EXPORT_SYMBOL_GPL(timerqueue_iterate_next);