iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

hrtimers: Avoid touching inactive timer bases

Browse Source 
Instead of iterating over all possible timer bases avoid it by marking
the active bases in the cpu base.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Peter Zijlstra <peterz@infradead.org>
This commit is contained in:
Thomas Gleixner 2011-05-20 13:05:15 +02:00
parent f24444b01b
commit ab8177bc53
6 changed files with 29 additions and 19 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
include/linux/hrtimer.h
View File

@ -143,7 +143,8 @@ struct hrtimer_sleeper {
*/
struct hrtimer_clock_base {
struct hrtimer_cpu_base *cpu_base;
clockid_t index;
int index;
clockid_t clockid;
struct timerqueue_head active;
ktime_t resolution;
ktime_t (*get_time)(void);
@ -162,7 +163,7 @@ enum hrtimer_base_type {
* struct hrtimer_cpu_base - the per cpu clock bases
* @lock: lock protecting the base and associated clock bases
* and timers
* @clock_base: array of clock bases for this cpu
* @active_bases: Bitfield to mark bases with active timers
* @expires_next: absolute time of the next event which was scheduled
* via clock_set_next_event()
* @hres_active: State of high resolution mode
@ -171,9 +172,11 @@ enum hrtimer_base_type {
* @nr_retries: Total number of hrtimer interrupt retries
* @nr_hangs: Total number of hrtimer interrupt hangs
* @max_hang_time: Maximum time spent in hrtimer_interrupt
* @clock_base: array of clock bases for this cpu
*/
struct hrtimer_cpu_base {
raw_spinlock_t lock;
unsigned long active_bases;
#ifdef CONFIG_HIGH_RES_TIMERS
ktime_t expires_next;
int hres_active;

2
include/linux/thread_info.h
View File

@ -29,7 +29,7 @@ struct restart_block {
} futex;
/* For nanosleep */
struct {
clockid_t index;
clockid_t clockid;
struct timespec __user *rmtp;
#ifdef CONFIG_COMPAT
struct compat_timespec __user *compat_rmtp;

29
kernel/hrtimer.c
View File

@ -64,17 +64,20 @@ DEFINE_PER_CPU(struct hrtimer_cpu_base, hrtimer_bases) =
.clock_base =
{
{
.index = CLOCK_REALTIME,
.index = HRTIMER_BASE_REALTIME,
.clockid = CLOCK_REALTIME,
.get_time = &ktime_get_real,
.resolution = KTIME_LOW_RES,
},
{
.index = CLOCK_MONOTONIC,
.index = HRTIMER_BASE_MONOTONIC,
.clockid = CLOCK_MONOTONIC,
.get_time = &ktime_get,
.resolution = KTIME_LOW_RES,
},
{
.index = CLOCK_BOOTTIME,
.index = HRTIMER_BASE_BOOTTIME,
.clockid = CLOCK_BOOTTIME,
.get_time = &ktime_get_boottime,
.resolution = KTIME_LOW_RES,
},
@ -196,7 +199,7 @@ switch_hrtimer_base(struct hrtimer *timer, struct hrtimer_clock_base *base,
struct hrtimer_cpu_base *new_cpu_base;
int this_cpu = smp_processor_id();
int cpu = hrtimer_get_target(this_cpu, pinned);
int basenum = hrtimer_clockid_to_base(base->index);
int basenum = base->index;
again:
new_cpu_base = &per_cpu(hrtimer_bases, cpu);
@ -857,6 +860,7 @@ static int enqueue_hrtimer(struct hrtimer *timer,
debug_activate(timer);
timerqueue_add(&base->active, &timer->node);
base->cpu_base->active_bases |= 1 << base->index;
/*
* HRTIMER_STATE_ENQUEUED is or'ed to the current state to preserve the
@ -898,6 +902,8 @@ static void __remove_hrtimer(struct hrtimer *timer,
#endif
}
timerqueue_del(&base->active, &timer->node);
if (!timerqueue_getnext(&base->active))
base->cpu_base->active_bases &= ~(1 << base->index);
out:
timer->state = newstate;
}
@ -1235,7 +1241,6 @@ static void __run_hrtimer(struct hrtimer *timer, ktime_t *now)
void hrtimer_interrupt(struct clock_event_device *dev)
{
struct hrtimer_cpu_base *cpu_base = &__get_cpu_var(hrtimer_bases);
struct hrtimer_clock_base *base;
ktime_t expires_next, now, entry_time, delta;
int i, retries = 0;
@ -1257,12 +1262,15 @@ retry:
*/
cpu_base->expires_next.tv64 = KTIME_MAX;
base = cpu_base->clock_base;
for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++) {
ktime_t basenow;
struct hrtimer_clock_base *base;
struct timerqueue_node *node;
ktime_t basenow;
if (!(cpu_base->active_bases & (1 << i)))
continue;
base = cpu_base->clock_base + i;
basenow = ktime_add(now, base->offset);
while ((node = timerqueue_getnext(&base->active))) {
@ -1295,7 +1303,6 @@ retry:
__run_hrtimer(timer, &basenow);
}
base++;
}
/*
@ -1526,7 +1533,7 @@ long __sched hrtimer_nanosleep_restart(struct restart_block *restart)
struct timespec __user *rmtp;
int ret = 0;
hrtimer_init_on_stack(&t.timer, restart->nanosleep.index,
hrtimer_init_on_stack(&t.timer, restart->nanosleep.clockid,
HRTIMER_MODE_ABS);
hrtimer_set_expires_tv64(&t.timer, restart->nanosleep.expires);
@ -1578,7 +1585,7 @@ long hrtimer_nanosleep(struct timespec *rqtp, struct timespec __user *rmtp,
restart = &current_thread_info()->restart_block;
restart->fn = hrtimer_nanosleep_restart;
restart->nanosleep.index = t.timer.base->index;
restart->nanosleep.clockid = t.timer.base->clockid;
restart->nanosleep.rmtp = rmtp;
restart->nanosleep.expires = hrtimer_get_expires_tv64(&t.timer);

4
kernel/posix-cpu-timers.c
View File

@ -1514,7 +1514,7 @@ static int posix_cpu_nsleep(const clockid_t which_clock, int flags,
return -EFAULT;
restart_block->fn = posix_cpu_nsleep_restart;
restart_block->nanosleep.index = which_clock;
restart_block->nanosleep.clockid = which_clock;
restart_block->nanosleep.rmtp = rmtp;
restart_block->nanosleep.expires = timespec_to_ns(rqtp);
}
@ -1523,7 +1523,7 @@ static int posix_cpu_nsleep(const clockid_t which_clock, int flags,
static long posix_cpu_nsleep_restart(struct restart_block *restart_block)
{
clockid_t which_clock = restart_block->nanosleep.index;
clockid_t which_clock = restart_block->nanosleep.clockid;
struct timespec t;
struct itimerspec it;
int error;

2
kernel/posix-timers.c
View File

@ -1056,7 +1056,7 @@ SYSCALL_DEFINE4(clock_nanosleep, const clockid_t, which_clock, int, flags,
*/
long clock_nanosleep_restart(struct restart_block *restart_block)
{
clockid_t which_clock = restart_block->nanosleep.index;
clockid_t which_clock = restart_block->nanosleep.clockid;
struct k_clock *kc = clockid_to_kclock(which_clock);
if (WARN_ON_ONCE(!kc || !kc->nsleep_restart))

4
kernel/time/alarmtimer.c
View File

@ -494,7 +494,7 @@ static int update_rmtp(ktime_t exp, enum alarmtimer_type type,
*/
static long __sched alarm_timer_nsleep_restart(struct restart_block *restart)
{
enum alarmtimer_type type = restart->nanosleep.index;
enum alarmtimer_type type = restart->nanosleep.clockid;
ktime_t exp;
struct timespec __user *rmtp;
struct alarm alarm;
@ -573,7 +573,7 @@ static int alarm_timer_nsleep(const clockid_t which_clock, int flags,
restart = &current_thread_info()->restart_block;
restart->fn = alarm_timer_nsleep_restart;
restart->nanosleep.index = type;
restart->nanosleep.clockid = type;
restart->nanosleep.expires = exp.tv64;
restart->nanosleep.rmtp = rmtp;
ret = -ERESTART_RESTARTBLOCK;