2 * Implement CPU time clocks for the POSIX clock interface.
5 #include <linux/sched.h>
6 #include <linux/posix-timers.h>
7 #include <linux/errno.h>
8 #include <linux/math64.h>
9 #include <asm/uaccess.h>
10 #include <linux/kernel_stat.h>
13 * Called after updating RLIMIT_CPU to set timer expiration if necessary.
15 void update_rlimit_cpu(unsigned long rlim_new
)
17 cputime_t cputime
= secs_to_cputime(rlim_new
);
18 struct signal_struct
*const sig
= current
->signal
;
20 if (cputime_eq(sig
->it
[CPUCLOCK_PROF
].expires
, cputime_zero
) ||
21 cputime_gt(sig
->it
[CPUCLOCK_PROF
].expires
, cputime
)) {
22 spin_lock_irq(¤t
->sighand
->siglock
);
23 set_process_cpu_timer(current
, CPUCLOCK_PROF
, &cputime
, NULL
);
24 spin_unlock_irq(¤t
->sighand
->siglock
);
28 static int check_clock(const clockid_t which_clock
)
31 struct task_struct
*p
;
32 const pid_t pid
= CPUCLOCK_PID(which_clock
);
34 if (CPUCLOCK_WHICH(which_clock
) >= CPUCLOCK_MAX
)
40 read_lock(&tasklist_lock
);
41 p
= find_task_by_vpid(pid
);
42 if (!p
|| !(CPUCLOCK_PERTHREAD(which_clock
) ?
43 same_thread_group(p
, current
) : thread_group_leader(p
))) {
46 read_unlock(&tasklist_lock
);
51 static inline union cpu_time_count
52 timespec_to_sample(const clockid_t which_clock
, const struct timespec
*tp
)
54 union cpu_time_count ret
;
55 ret
.sched
= 0; /* high half always zero when .cpu used */
56 if (CPUCLOCK_WHICH(which_clock
) == CPUCLOCK_SCHED
) {
57 ret
.sched
= (unsigned long long)tp
->tv_sec
* NSEC_PER_SEC
+ tp
->tv_nsec
;
59 ret
.cpu
= timespec_to_cputime(tp
);
64 static void sample_to_timespec(const clockid_t which_clock
,
65 union cpu_time_count cpu
,
68 if (CPUCLOCK_WHICH(which_clock
) == CPUCLOCK_SCHED
)
69 *tp
= ns_to_timespec(cpu
.sched
);
71 cputime_to_timespec(cpu
.cpu
, tp
);
74 static inline int cpu_time_before(const clockid_t which_clock
,
75 union cpu_time_count now
,
76 union cpu_time_count then
)
78 if (CPUCLOCK_WHICH(which_clock
) == CPUCLOCK_SCHED
) {
79 return now
.sched
< then
.sched
;
81 return cputime_lt(now
.cpu
, then
.cpu
);
84 static inline void cpu_time_add(const clockid_t which_clock
,
85 union cpu_time_count
*acc
,
86 union cpu_time_count val
)
88 if (CPUCLOCK_WHICH(which_clock
) == CPUCLOCK_SCHED
) {
89 acc
->sched
+= val
.sched
;
91 acc
->cpu
= cputime_add(acc
->cpu
, val
.cpu
);
94 static inline union cpu_time_count
cpu_time_sub(const clockid_t which_clock
,
95 union cpu_time_count a
,
96 union cpu_time_count b
)
98 if (CPUCLOCK_WHICH(which_clock
) == CPUCLOCK_SCHED
) {
101 a
.cpu
= cputime_sub(a
.cpu
, b
.cpu
);
107 * Divide and limit the result to res >= 1
109 * This is necessary to prevent signal delivery starvation, when the result of
110 * the division would be rounded down to 0.
112 static inline cputime_t
cputime_div_non_zero(cputime_t time
, unsigned long div
)
114 cputime_t res
= cputime_div(time
, div
);
116 return max_t(cputime_t
, res
, 1);
120 * Update expiry time from increment, and increase overrun count,
121 * given the current clock sample.
123 static void bump_cpu_timer(struct k_itimer
*timer
,
124 union cpu_time_count now
)
128 if (timer
->it
.cpu
.incr
.sched
== 0)
131 if (CPUCLOCK_WHICH(timer
->it_clock
) == CPUCLOCK_SCHED
) {
132 unsigned long long delta
, incr
;
134 if (now
.sched
< timer
->it
.cpu
.expires
.sched
)
136 incr
= timer
->it
.cpu
.incr
.sched
;
137 delta
= now
.sched
+ incr
- timer
->it
.cpu
.expires
.sched
;
138 /* Don't use (incr*2 < delta), incr*2 might overflow. */
139 for (i
= 0; incr
< delta
- incr
; i
++)
141 for (; i
>= 0; incr
>>= 1, i
--) {
144 timer
->it
.cpu
.expires
.sched
+= incr
;
145 timer
->it_overrun
+= 1 << i
;
149 cputime_t delta
, incr
;
151 if (cputime_lt(now
.cpu
, timer
->it
.cpu
.expires
.cpu
))
153 incr
= timer
->it
.cpu
.incr
.cpu
;
154 delta
= cputime_sub(cputime_add(now
.cpu
, incr
),
155 timer
->it
.cpu
.expires
.cpu
);
156 /* Don't use (incr*2 < delta), incr*2 might overflow. */
157 for (i
= 0; cputime_lt(incr
, cputime_sub(delta
, incr
)); i
++)
158 incr
= cputime_add(incr
, incr
);
159 for (; i
>= 0; incr
= cputime_halve(incr
), i
--) {
160 if (cputime_lt(delta
, incr
))
162 timer
->it
.cpu
.expires
.cpu
=
163 cputime_add(timer
->it
.cpu
.expires
.cpu
, incr
);
164 timer
->it_overrun
+= 1 << i
;
165 delta
= cputime_sub(delta
, incr
);
170 static inline cputime_t
prof_ticks(struct task_struct
*p
)
172 return cputime_add(p
->utime
, p
->stime
);
174 static inline cputime_t
virt_ticks(struct task_struct
*p
)
179 int posix_cpu_clock_getres(const clockid_t which_clock
, struct timespec
*tp
)
181 int error
= check_clock(which_clock
);
184 tp
->tv_nsec
= ((NSEC_PER_SEC
+ HZ
- 1) / HZ
);
185 if (CPUCLOCK_WHICH(which_clock
) == CPUCLOCK_SCHED
) {
187 * If sched_clock is using a cycle counter, we
188 * don't have any idea of its true resolution
189 * exported, but it is much more than 1s/HZ.
197 int posix_cpu_clock_set(const clockid_t which_clock
, const struct timespec
*tp
)
200 * You can never reset a CPU clock, but we check for other errors
201 * in the call before failing with EPERM.
203 int error
= check_clock(which_clock
);
212 * Sample a per-thread clock for the given task.
214 static int cpu_clock_sample(const clockid_t which_clock
, struct task_struct
*p
,
215 union cpu_time_count
*cpu
)
217 switch (CPUCLOCK_WHICH(which_clock
)) {
221 cpu
->cpu
= prof_ticks(p
);
224 cpu
->cpu
= virt_ticks(p
);
227 cpu
->sched
= task_sched_runtime(p
);
233 void thread_group_cputime(struct task_struct
*tsk
, struct task_cputime
*times
)
235 struct sighand_struct
*sighand
;
236 struct signal_struct
*sig
;
237 struct task_struct
*t
;
239 *times
= INIT_CPUTIME
;
242 sighand
= rcu_dereference(tsk
->sighand
);
250 times
->utime
= cputime_add(times
->utime
, t
->utime
);
251 times
->stime
= cputime_add(times
->stime
, t
->stime
);
252 times
->sum_exec_runtime
+= t
->se
.sum_exec_runtime
;
257 times
->utime
= cputime_add(times
->utime
, sig
->utime
);
258 times
->stime
= cputime_add(times
->stime
, sig
->stime
);
259 times
->sum_exec_runtime
+= sig
->sum_sched_runtime
;
264 static void update_gt_cputime(struct task_cputime
*a
, struct task_cputime
*b
)
266 if (cputime_gt(b
->utime
, a
->utime
))
269 if (cputime_gt(b
->stime
, a
->stime
))
272 if (b
->sum_exec_runtime
> a
->sum_exec_runtime
)
273 a
->sum_exec_runtime
= b
->sum_exec_runtime
;
276 void thread_group_cputimer(struct task_struct
*tsk
, struct task_cputime
*times
)
278 struct thread_group_cputimer
*cputimer
= &tsk
->signal
->cputimer
;
279 struct task_cputime sum
;
282 spin_lock_irqsave(&cputimer
->lock
, flags
);
283 if (!cputimer
->running
) {
284 cputimer
->running
= 1;
286 * The POSIX timer interface allows for absolute time expiry
287 * values through the TIMER_ABSTIME flag, therefore we have
288 * to synchronize the timer to the clock every time we start
291 thread_group_cputime(tsk
, &sum
);
292 update_gt_cputime(&cputimer
->cputime
, &sum
);
294 *times
= cputimer
->cputime
;
295 spin_unlock_irqrestore(&cputimer
->lock
, flags
);
299 * Sample a process (thread group) clock for the given group_leader task.
300 * Must be called with tasklist_lock held for reading.
302 static int cpu_clock_sample_group(const clockid_t which_clock
,
303 struct task_struct
*p
,
304 union cpu_time_count
*cpu
)
306 struct task_cputime cputime
;
308 switch (CPUCLOCK_WHICH(which_clock
)) {
312 thread_group_cputime(p
, &cputime
);
313 cpu
->cpu
= cputime_add(cputime
.utime
, cputime
.stime
);
316 thread_group_cputime(p
, &cputime
);
317 cpu
->cpu
= cputime
.utime
;
320 cpu
->sched
= thread_group_sched_runtime(p
);
327 int posix_cpu_clock_get(const clockid_t which_clock
, struct timespec
*tp
)
329 const pid_t pid
= CPUCLOCK_PID(which_clock
);
331 union cpu_time_count rtn
;
335 * Special case constant value for our own clocks.
336 * We don't have to do any lookup to find ourselves.
338 if (CPUCLOCK_PERTHREAD(which_clock
)) {
340 * Sampling just ourselves we can do with no locking.
342 error
= cpu_clock_sample(which_clock
,
345 read_lock(&tasklist_lock
);
346 error
= cpu_clock_sample_group(which_clock
,
348 read_unlock(&tasklist_lock
);
352 * Find the given PID, and validate that the caller
353 * should be able to see it.
355 struct task_struct
*p
;
357 p
= find_task_by_vpid(pid
);
359 if (CPUCLOCK_PERTHREAD(which_clock
)) {
360 if (same_thread_group(p
, current
)) {
361 error
= cpu_clock_sample(which_clock
,
365 read_lock(&tasklist_lock
);
366 if (thread_group_leader(p
) && p
->signal
) {
368 cpu_clock_sample_group(which_clock
,
371 read_unlock(&tasklist_lock
);
379 sample_to_timespec(which_clock
, rtn
, tp
);
385 * Validate the clockid_t for a new CPU-clock timer, and initialize the timer.
386 * This is called from sys_timer_create with the new timer already locked.
388 int posix_cpu_timer_create(struct k_itimer
*new_timer
)
391 const pid_t pid
= CPUCLOCK_PID(new_timer
->it_clock
);
392 struct task_struct
*p
;
394 if (CPUCLOCK_WHICH(new_timer
->it_clock
) >= CPUCLOCK_MAX
)
397 INIT_LIST_HEAD(&new_timer
->it
.cpu
.entry
);
398 new_timer
->it
.cpu
.incr
.sched
= 0;
399 new_timer
->it
.cpu
.expires
.sched
= 0;
401 read_lock(&tasklist_lock
);
402 if (CPUCLOCK_PERTHREAD(new_timer
->it_clock
)) {
406 p
= find_task_by_vpid(pid
);
407 if (p
&& !same_thread_group(p
, current
))
412 p
= current
->group_leader
;
414 p
= find_task_by_vpid(pid
);
415 if (p
&& !thread_group_leader(p
))
419 new_timer
->it
.cpu
.task
= p
;
425 read_unlock(&tasklist_lock
);
431 * Clean up a CPU-clock timer that is about to be destroyed.
432 * This is called from timer deletion with the timer already locked.
433 * If we return TIMER_RETRY, it's necessary to release the timer's lock
434 * and try again. (This happens when the timer is in the middle of firing.)
436 int posix_cpu_timer_del(struct k_itimer
*timer
)
438 struct task_struct
*p
= timer
->it
.cpu
.task
;
441 if (likely(p
!= NULL
)) {
442 read_lock(&tasklist_lock
);
443 if (unlikely(p
->signal
== NULL
)) {
445 * We raced with the reaping of the task.
446 * The deletion should have cleared us off the list.
448 BUG_ON(!list_empty(&timer
->it
.cpu
.entry
));
450 spin_lock(&p
->sighand
->siglock
);
451 if (timer
->it
.cpu
.firing
)
454 list_del(&timer
->it
.cpu
.entry
);
455 spin_unlock(&p
->sighand
->siglock
);
457 read_unlock(&tasklist_lock
);
467 * Clean out CPU timers still ticking when a thread exited. The task
468 * pointer is cleared, and the expiry time is replaced with the residual
469 * time for later timer_gettime calls to return.
470 * This must be called with the siglock held.
472 static void cleanup_timers(struct list_head
*head
,
473 cputime_t utime
, cputime_t stime
,
474 unsigned long long sum_exec_runtime
)
476 struct cpu_timer_list
*timer
, *next
;
477 cputime_t ptime
= cputime_add(utime
, stime
);
479 list_for_each_entry_safe(timer
, next
, head
, entry
) {
480 list_del_init(&timer
->entry
);
481 if (cputime_lt(timer
->expires
.cpu
, ptime
)) {
482 timer
->expires
.cpu
= cputime_zero
;
484 timer
->expires
.cpu
= cputime_sub(timer
->expires
.cpu
,
490 list_for_each_entry_safe(timer
, next
, head
, entry
) {
491 list_del_init(&timer
->entry
);
492 if (cputime_lt(timer
->expires
.cpu
, utime
)) {
493 timer
->expires
.cpu
= cputime_zero
;
495 timer
->expires
.cpu
= cputime_sub(timer
->expires
.cpu
,
501 list_for_each_entry_safe(timer
, next
, head
, entry
) {
502 list_del_init(&timer
->entry
);
503 if (timer
->expires
.sched
< sum_exec_runtime
) {
504 timer
->expires
.sched
= 0;
506 timer
->expires
.sched
-= sum_exec_runtime
;
512 * These are both called with the siglock held, when the current thread
513 * is being reaped. When the final (leader) thread in the group is reaped,
514 * posix_cpu_timers_exit_group will be called after posix_cpu_timers_exit.
516 void posix_cpu_timers_exit(struct task_struct
*tsk
)
518 cleanup_timers(tsk
->cpu_timers
,
519 tsk
->utime
, tsk
->stime
, tsk
->se
.sum_exec_runtime
);
522 void posix_cpu_timers_exit_group(struct task_struct
*tsk
)
524 struct task_cputime cputime
;
526 thread_group_cputimer(tsk
, &cputime
);
527 cleanup_timers(tsk
->signal
->cpu_timers
,
528 cputime
.utime
, cputime
.stime
, cputime
.sum_exec_runtime
);
531 static void clear_dead_task(struct k_itimer
*timer
, union cpu_time_count now
)
534 * That's all for this thread or process.
535 * We leave our residual in expires to be reported.
537 put_task_struct(timer
->it
.cpu
.task
);
538 timer
->it
.cpu
.task
= NULL
;
539 timer
->it
.cpu
.expires
= cpu_time_sub(timer
->it_clock
,
540 timer
->it
.cpu
.expires
,
544 static inline int expires_gt(cputime_t expires
, cputime_t new_exp
)
546 return cputime_eq(expires
, cputime_zero
) ||
547 cputime_gt(expires
, new_exp
);
550 static inline int expires_le(cputime_t expires
, cputime_t new_exp
)
552 return !cputime_eq(expires
, cputime_zero
) &&
553 cputime_le(expires
, new_exp
);
556 * Insert the timer on the appropriate list before any timers that
557 * expire later. This must be called with the tasklist_lock held
558 * for reading, and interrupts disabled.
560 static void arm_timer(struct k_itimer
*timer
, union cpu_time_count now
)
562 struct task_struct
*p
= timer
->it
.cpu
.task
;
563 struct list_head
*head
, *listpos
;
564 struct cpu_timer_list
*const nt
= &timer
->it
.cpu
;
565 struct cpu_timer_list
*next
;
568 head
= (CPUCLOCK_PERTHREAD(timer
->it_clock
) ?
569 p
->cpu_timers
: p
->signal
->cpu_timers
);
570 head
+= CPUCLOCK_WHICH(timer
->it_clock
);
572 BUG_ON(!irqs_disabled());
573 spin_lock(&p
->sighand
->siglock
);
576 if (CPUCLOCK_WHICH(timer
->it_clock
) == CPUCLOCK_SCHED
) {
577 list_for_each_entry(next
, head
, entry
) {
578 if (next
->expires
.sched
> nt
->expires
.sched
)
580 listpos
= &next
->entry
;
583 list_for_each_entry(next
, head
, entry
) {
584 if (cputime_gt(next
->expires
.cpu
, nt
->expires
.cpu
))
586 listpos
= &next
->entry
;
589 list_add(&nt
->entry
, listpos
);
591 if (listpos
== head
) {
593 * We are the new earliest-expiring timer.
594 * If we are a thread timer, there can always
595 * be a process timer telling us to stop earlier.
598 if (CPUCLOCK_PERTHREAD(timer
->it_clock
)) {
599 union cpu_time_count
*exp
= &nt
->expires
;
601 switch (CPUCLOCK_WHICH(timer
->it_clock
)) {
605 if (expires_gt(p
->cputime_expires
.prof_exp
,
607 p
->cputime_expires
.prof_exp
= exp
->cpu
;
610 if (expires_gt(p
->cputime_expires
.virt_exp
,
612 p
->cputime_expires
.virt_exp
= exp
->cpu
;
615 if (p
->cputime_expires
.sched_exp
== 0 ||
616 p
->cputime_expires
.sched_exp
> exp
->sched
)
617 p
->cputime_expires
.sched_exp
=
622 struct signal_struct
*const sig
= p
->signal
;
623 union cpu_time_count
*exp
= &timer
->it
.cpu
.expires
;
626 * For a process timer, set the cached expiration time.
628 switch (CPUCLOCK_WHICH(timer
->it_clock
)) {
632 if (expires_le(sig
->it
[CPUCLOCK_VIRT
].expires
,
635 sig
->cputime_expires
.virt_exp
= exp
->cpu
;
638 if (expires_le(sig
->it
[CPUCLOCK_PROF
].expires
,
641 i
= sig
->rlim
[RLIMIT_CPU
].rlim_cur
;
642 if (i
!= RLIM_INFINITY
&&
643 i
<= cputime_to_secs(exp
->cpu
))
645 sig
->cputime_expires
.prof_exp
= exp
->cpu
;
648 sig
->cputime_expires
.sched_exp
= exp
->sched
;
654 spin_unlock(&p
->sighand
->siglock
);
658 * The timer is locked, fire it and arrange for its reload.
660 static void cpu_timer_fire(struct k_itimer
*timer
)
662 if (unlikely(timer
->sigq
== NULL
)) {
664 * This a special case for clock_nanosleep,
665 * not a normal timer from sys_timer_create.
667 wake_up_process(timer
->it_process
);
668 timer
->it
.cpu
.expires
.sched
= 0;
669 } else if (timer
->it
.cpu
.incr
.sched
== 0) {
671 * One-shot timer. Clear it as soon as it's fired.
673 posix_timer_event(timer
, 0);
674 timer
->it
.cpu
.expires
.sched
= 0;
675 } else if (posix_timer_event(timer
, ++timer
->it_requeue_pending
)) {
677 * The signal did not get queued because the signal
678 * was ignored, so we won't get any callback to
679 * reload the timer. But we need to keep it
680 * ticking in case the signal is deliverable next time.
682 posix_cpu_timer_schedule(timer
);
687 * Sample a process (thread group) timer for the given group_leader task.
688 * Must be called with tasklist_lock held for reading.
690 static int cpu_timer_sample_group(const clockid_t which_clock
,
691 struct task_struct
*p
,
692 union cpu_time_count
*cpu
)
694 struct task_cputime cputime
;
696 thread_group_cputimer(p
, &cputime
);
697 switch (CPUCLOCK_WHICH(which_clock
)) {
701 cpu
->cpu
= cputime_add(cputime
.utime
, cputime
.stime
);
704 cpu
->cpu
= cputime
.utime
;
707 cpu
->sched
= cputime
.sum_exec_runtime
+ task_delta_exec(p
);
714 * Guts of sys_timer_settime for CPU timers.
715 * This is called with the timer locked and interrupts disabled.
716 * If we return TIMER_RETRY, it's necessary to release the timer's lock
717 * and try again. (This happens when the timer is in the middle of firing.)
719 int posix_cpu_timer_set(struct k_itimer
*timer
, int flags
,
720 struct itimerspec
*new, struct itimerspec
*old
)
722 struct task_struct
*p
= timer
->it
.cpu
.task
;
723 union cpu_time_count old_expires
, new_expires
, val
;
726 if (unlikely(p
== NULL
)) {
728 * Timer refers to a dead task's clock.
733 new_expires
= timespec_to_sample(timer
->it_clock
, &new->it_value
);
735 read_lock(&tasklist_lock
);
737 * We need the tasklist_lock to protect against reaping that
738 * clears p->signal. If p has just been reaped, we can no
739 * longer get any information about it at all.
741 if (unlikely(p
->signal
== NULL
)) {
742 read_unlock(&tasklist_lock
);
744 timer
->it
.cpu
.task
= NULL
;
749 * Disarm any old timer after extracting its expiry time.
751 BUG_ON(!irqs_disabled());
754 spin_lock(&p
->sighand
->siglock
);
755 old_expires
= timer
->it
.cpu
.expires
;
756 if (unlikely(timer
->it
.cpu
.firing
)) {
757 timer
->it
.cpu
.firing
= -1;
760 list_del_init(&timer
->it
.cpu
.entry
);
761 spin_unlock(&p
->sighand
->siglock
);
764 * We need to sample the current value to convert the new
765 * value from to relative and absolute, and to convert the
766 * old value from absolute to relative. To set a process
767 * timer, we need a sample to balance the thread expiry
768 * times (in arm_timer). With an absolute time, we must
769 * check if it's already passed. In short, we need a sample.
771 if (CPUCLOCK_PERTHREAD(timer
->it_clock
)) {
772 cpu_clock_sample(timer
->it_clock
, p
, &val
);
774 cpu_timer_sample_group(timer
->it_clock
, p
, &val
);
778 if (old_expires
.sched
== 0) {
779 old
->it_value
.tv_sec
= 0;
780 old
->it_value
.tv_nsec
= 0;
783 * Update the timer in case it has
784 * overrun already. If it has,
785 * we'll report it as having overrun
786 * and with the next reloaded timer
787 * already ticking, though we are
788 * swallowing that pending
789 * notification here to install the
792 bump_cpu_timer(timer
, val
);
793 if (cpu_time_before(timer
->it_clock
, val
,
794 timer
->it
.cpu
.expires
)) {
795 old_expires
= cpu_time_sub(
797 timer
->it
.cpu
.expires
, val
);
798 sample_to_timespec(timer
->it_clock
,
802 old
->it_value
.tv_nsec
= 1;
803 old
->it_value
.tv_sec
= 0;
810 * We are colliding with the timer actually firing.
811 * Punt after filling in the timer's old value, and
812 * disable this firing since we are already reporting
813 * it as an overrun (thanks to bump_cpu_timer above).
815 read_unlock(&tasklist_lock
);
819 if (new_expires
.sched
!= 0 && !(flags
& TIMER_ABSTIME
)) {
820 cpu_time_add(timer
->it_clock
, &new_expires
, val
);
824 * Install the new expiry time (or zero).
825 * For a timer with no notification action, we don't actually
826 * arm the timer (we'll just fake it for timer_gettime).
828 timer
->it
.cpu
.expires
= new_expires
;
829 if (new_expires
.sched
!= 0 &&
830 (timer
->it_sigev_notify
& ~SIGEV_THREAD_ID
) != SIGEV_NONE
&&
831 cpu_time_before(timer
->it_clock
, val
, new_expires
)) {
832 arm_timer(timer
, val
);
835 read_unlock(&tasklist_lock
);
838 * Install the new reload setting, and
839 * set up the signal and overrun bookkeeping.
841 timer
->it
.cpu
.incr
= timespec_to_sample(timer
->it_clock
,
845 * This acts as a modification timestamp for the timer,
846 * so any automatic reload attempt will punt on seeing
847 * that we have reset the timer manually.
849 timer
->it_requeue_pending
= (timer
->it_requeue_pending
+ 2) &
851 timer
->it_overrun_last
= 0;
852 timer
->it_overrun
= -1;
854 if (new_expires
.sched
!= 0 &&
855 (timer
->it_sigev_notify
& ~SIGEV_THREAD_ID
) != SIGEV_NONE
&&
856 !cpu_time_before(timer
->it_clock
, val
, new_expires
)) {
858 * The designated time already passed, so we notify
859 * immediately, even if the thread never runs to
860 * accumulate more time on this clock.
862 cpu_timer_fire(timer
);
868 sample_to_timespec(timer
->it_clock
,
869 timer
->it
.cpu
.incr
, &old
->it_interval
);
874 void posix_cpu_timer_get(struct k_itimer
*timer
, struct itimerspec
*itp
)
876 union cpu_time_count now
;
877 struct task_struct
*p
= timer
->it
.cpu
.task
;
881 * Easy part: convert the reload time.
883 sample_to_timespec(timer
->it_clock
,
884 timer
->it
.cpu
.incr
, &itp
->it_interval
);
886 if (timer
->it
.cpu
.expires
.sched
== 0) { /* Timer not armed at all. */
887 itp
->it_value
.tv_sec
= itp
->it_value
.tv_nsec
= 0;
891 if (unlikely(p
== NULL
)) {
893 * This task already died and the timer will never fire.
894 * In this case, expires is actually the dead value.
897 sample_to_timespec(timer
->it_clock
, timer
->it
.cpu
.expires
,
903 * Sample the clock to take the difference with the expiry time.
905 if (CPUCLOCK_PERTHREAD(timer
->it_clock
)) {
906 cpu_clock_sample(timer
->it_clock
, p
, &now
);
907 clear_dead
= p
->exit_state
;
909 read_lock(&tasklist_lock
);
910 if (unlikely(p
->signal
== NULL
)) {
912 * The process has been reaped.
913 * We can't even collect a sample any more.
914 * Call the timer disarmed, nothing else to do.
917 timer
->it
.cpu
.task
= NULL
;
918 timer
->it
.cpu
.expires
.sched
= 0;
919 read_unlock(&tasklist_lock
);
922 cpu_timer_sample_group(timer
->it_clock
, p
, &now
);
923 clear_dead
= (unlikely(p
->exit_state
) &&
924 thread_group_empty(p
));
926 read_unlock(&tasklist_lock
);
929 if ((timer
->it_sigev_notify
& ~SIGEV_THREAD_ID
) == SIGEV_NONE
) {
930 if (timer
->it
.cpu
.incr
.sched
== 0 &&
931 cpu_time_before(timer
->it_clock
,
932 timer
->it
.cpu
.expires
, now
)) {
934 * Do-nothing timer expired and has no reload,
935 * so it's as if it was never set.
937 timer
->it
.cpu
.expires
.sched
= 0;
938 itp
->it_value
.tv_sec
= itp
->it_value
.tv_nsec
= 0;
942 * Account for any expirations and reloads that should
945 bump_cpu_timer(timer
, now
);
948 if (unlikely(clear_dead
)) {
950 * We've noticed that the thread is dead, but
951 * not yet reaped. Take this opportunity to
954 clear_dead_task(timer
, now
);
958 if (cpu_time_before(timer
->it_clock
, now
, timer
->it
.cpu
.expires
)) {
959 sample_to_timespec(timer
->it_clock
,
960 cpu_time_sub(timer
->it_clock
,
961 timer
->it
.cpu
.expires
, now
),
965 * The timer should have expired already, but the firing
966 * hasn't taken place yet. Say it's just about to expire.
968 itp
->it_value
.tv_nsec
= 1;
969 itp
->it_value
.tv_sec
= 0;
974 * Check for any per-thread CPU timers that have fired and move them off
975 * the tsk->cpu_timers[N] list onto the firing list. Here we update the
976 * tsk->it_*_expires values to reflect the remaining thread CPU timers.
978 static void check_thread_timers(struct task_struct
*tsk
,
979 struct list_head
*firing
)
982 struct list_head
*timers
= tsk
->cpu_timers
;
983 struct signal_struct
*const sig
= tsk
->signal
;
986 tsk
->cputime_expires
.prof_exp
= cputime_zero
;
987 while (!list_empty(timers
)) {
988 struct cpu_timer_list
*t
= list_first_entry(timers
,
989 struct cpu_timer_list
,
991 if (!--maxfire
|| cputime_lt(prof_ticks(tsk
), t
->expires
.cpu
)) {
992 tsk
->cputime_expires
.prof_exp
= t
->expires
.cpu
;
996 list_move_tail(&t
->entry
, firing
);
1001 tsk
->cputime_expires
.virt_exp
= cputime_zero
;
1002 while (!list_empty(timers
)) {
1003 struct cpu_timer_list
*t
= list_first_entry(timers
,
1004 struct cpu_timer_list
,
1006 if (!--maxfire
|| cputime_lt(virt_ticks(tsk
), t
->expires
.cpu
)) {
1007 tsk
->cputime_expires
.virt_exp
= t
->expires
.cpu
;
1011 list_move_tail(&t
->entry
, firing
);
1016 tsk
->cputime_expires
.sched_exp
= 0;
1017 while (!list_empty(timers
)) {
1018 struct cpu_timer_list
*t
= list_first_entry(timers
,
1019 struct cpu_timer_list
,
1021 if (!--maxfire
|| tsk
->se
.sum_exec_runtime
< t
->expires
.sched
) {
1022 tsk
->cputime_expires
.sched_exp
= t
->expires
.sched
;
1026 list_move_tail(&t
->entry
, firing
);
1030 * Check for the special case thread timers.
1032 if (sig
->rlim
[RLIMIT_RTTIME
].rlim_cur
!= RLIM_INFINITY
) {
1033 unsigned long hard
= sig
->rlim
[RLIMIT_RTTIME
].rlim_max
;
1034 unsigned long *soft
= &sig
->rlim
[RLIMIT_RTTIME
].rlim_cur
;
1036 if (hard
!= RLIM_INFINITY
&&
1037 tsk
->rt
.timeout
> DIV_ROUND_UP(hard
, USEC_PER_SEC
/HZ
)) {
1039 * At the hard limit, we just die.
1040 * No need to calculate anything else now.
1042 __group_send_sig_info(SIGKILL
, SEND_SIG_PRIV
, tsk
);
1045 if (tsk
->rt
.timeout
> DIV_ROUND_UP(*soft
, USEC_PER_SEC
/HZ
)) {
1047 * At the soft limit, send a SIGXCPU every second.
1049 if (sig
->rlim
[RLIMIT_RTTIME
].rlim_cur
1050 < sig
->rlim
[RLIMIT_RTTIME
].rlim_max
) {
1051 sig
->rlim
[RLIMIT_RTTIME
].rlim_cur
+=
1055 "RT Watchdog Timeout: %s[%d]\n",
1056 tsk
->comm
, task_pid_nr(tsk
));
1057 __group_send_sig_info(SIGXCPU
, SEND_SIG_PRIV
, tsk
);
1062 static void stop_process_timers(struct task_struct
*tsk
)
1064 struct thread_group_cputimer
*cputimer
= &tsk
->signal
->cputimer
;
1065 unsigned long flags
;
1067 if (!cputimer
->running
)
1070 spin_lock_irqsave(&cputimer
->lock
, flags
);
1071 cputimer
->running
= 0;
1072 spin_unlock_irqrestore(&cputimer
->lock
, flags
);
1075 static u32 onecputick
;
1077 static void check_cpu_itimer(struct task_struct
*tsk
, struct cpu_itimer
*it
,
1078 cputime_t
*expires
, cputime_t cur_time
, int signo
)
1080 if (cputime_eq(it
->expires
, cputime_zero
))
1083 if (cputime_ge(cur_time
, it
->expires
)) {
1084 if (!cputime_eq(it
->incr
, cputime_zero
)) {
1085 it
->expires
= cputime_add(it
->expires
, it
->incr
);
1086 it
->error
+= it
->incr_error
;
1087 if (it
->error
>= onecputick
) {
1088 it
->expires
= cputime_sub(it
->expires
,
1090 it
->error
-= onecputick
;
1093 it
->expires
= cputime_zero
;
1095 __group_send_sig_info(signo
, SEND_SIG_PRIV
, tsk
);
1098 if (!cputime_eq(it
->expires
, cputime_zero
) &&
1099 (cputime_eq(*expires
, cputime_zero
) ||
1100 cputime_lt(it
->expires
, *expires
))) {
1101 *expires
= it
->expires
;
1106 * Check for any per-thread CPU timers that have fired and move them
1107 * off the tsk->*_timers list onto the firing list. Per-thread timers
1108 * have already been taken off.
1110 static void check_process_timers(struct task_struct
*tsk
,
1111 struct list_head
*firing
)
1114 struct signal_struct
*const sig
= tsk
->signal
;
1115 cputime_t utime
, ptime
, virt_expires
, prof_expires
;
1116 unsigned long long sum_sched_runtime
, sched_expires
;
1117 struct list_head
*timers
= sig
->cpu_timers
;
1118 struct task_cputime cputime
;
1121 * Don't sample the current process CPU clocks if there are no timers.
1123 if (list_empty(&timers
[CPUCLOCK_PROF
]) &&
1124 cputime_eq(sig
->it
[CPUCLOCK_PROF
].expires
, cputime_zero
) &&
1125 sig
->rlim
[RLIMIT_CPU
].rlim_cur
== RLIM_INFINITY
&&
1126 list_empty(&timers
[CPUCLOCK_VIRT
]) &&
1127 cputime_eq(sig
->it
[CPUCLOCK_VIRT
].expires
, cputime_zero
) &&
1128 list_empty(&timers
[CPUCLOCK_SCHED
])) {
1129 stop_process_timers(tsk
);
1134 * Collect the current process totals.
1136 thread_group_cputimer(tsk
, &cputime
);
1137 utime
= cputime
.utime
;
1138 ptime
= cputime_add(utime
, cputime
.stime
);
1139 sum_sched_runtime
= cputime
.sum_exec_runtime
;
1141 prof_expires
= cputime_zero
;
1142 while (!list_empty(timers
)) {
1143 struct cpu_timer_list
*tl
= list_first_entry(timers
,
1144 struct cpu_timer_list
,
1146 if (!--maxfire
|| cputime_lt(ptime
, tl
->expires
.cpu
)) {
1147 prof_expires
= tl
->expires
.cpu
;
1151 list_move_tail(&tl
->entry
, firing
);
1156 virt_expires
= cputime_zero
;
1157 while (!list_empty(timers
)) {
1158 struct cpu_timer_list
*tl
= list_first_entry(timers
,
1159 struct cpu_timer_list
,
1161 if (!--maxfire
|| cputime_lt(utime
, tl
->expires
.cpu
)) {
1162 virt_expires
= tl
->expires
.cpu
;
1166 list_move_tail(&tl
->entry
, firing
);
1172 while (!list_empty(timers
)) {
1173 struct cpu_timer_list
*tl
= list_first_entry(timers
,
1174 struct cpu_timer_list
,
1176 if (!--maxfire
|| sum_sched_runtime
< tl
->expires
.sched
) {
1177 sched_expires
= tl
->expires
.sched
;
1181 list_move_tail(&tl
->entry
, firing
);
1185 * Check for the special case process timers.
1187 check_cpu_itimer(tsk
, &sig
->it
[CPUCLOCK_PROF
], &prof_expires
, ptime
,
1189 check_cpu_itimer(tsk
, &sig
->it
[CPUCLOCK_VIRT
], &virt_expires
, utime
,
1192 if (sig
->rlim
[RLIMIT_CPU
].rlim_cur
!= RLIM_INFINITY
) {
1193 unsigned long psecs
= cputime_to_secs(ptime
);
1195 if (psecs
>= sig
->rlim
[RLIMIT_CPU
].rlim_max
) {
1197 * At the hard limit, we just die.
1198 * No need to calculate anything else now.
1200 __group_send_sig_info(SIGKILL
, SEND_SIG_PRIV
, tsk
);
1203 if (psecs
>= sig
->rlim
[RLIMIT_CPU
].rlim_cur
) {
1205 * At the soft limit, send a SIGXCPU every second.
1207 __group_send_sig_info(SIGXCPU
, SEND_SIG_PRIV
, tsk
);
1208 if (sig
->rlim
[RLIMIT_CPU
].rlim_cur
1209 < sig
->rlim
[RLIMIT_CPU
].rlim_max
) {
1210 sig
->rlim
[RLIMIT_CPU
].rlim_cur
++;
1213 x
= secs_to_cputime(sig
->rlim
[RLIMIT_CPU
].rlim_cur
);
1214 if (cputime_eq(prof_expires
, cputime_zero
) ||
1215 cputime_lt(x
, prof_expires
)) {
1220 if (!cputime_eq(prof_expires
, cputime_zero
) &&
1221 (cputime_eq(sig
->cputime_expires
.prof_exp
, cputime_zero
) ||
1222 cputime_gt(sig
->cputime_expires
.prof_exp
, prof_expires
)))
1223 sig
->cputime_expires
.prof_exp
= prof_expires
;
1224 if (!cputime_eq(virt_expires
, cputime_zero
) &&
1225 (cputime_eq(sig
->cputime_expires
.virt_exp
, cputime_zero
) ||
1226 cputime_gt(sig
->cputime_expires
.virt_exp
, virt_expires
)))
1227 sig
->cputime_expires
.virt_exp
= virt_expires
;
1228 if (sched_expires
!= 0 &&
1229 (sig
->cputime_expires
.sched_exp
== 0 ||
1230 sig
->cputime_expires
.sched_exp
> sched_expires
))
1231 sig
->cputime_expires
.sched_exp
= sched_expires
;
1235 * This is called from the signal code (via do_schedule_next_timer)
1236 * when the last timer signal was delivered and we have to reload the timer.
1238 void posix_cpu_timer_schedule(struct k_itimer
*timer
)
1240 struct task_struct
*p
= timer
->it
.cpu
.task
;
1241 union cpu_time_count now
;
1243 if (unlikely(p
== NULL
))
1245 * The task was cleaned up already, no future firings.
1250 * Fetch the current sample and update the timer's expiry time.
1252 if (CPUCLOCK_PERTHREAD(timer
->it_clock
)) {
1253 cpu_clock_sample(timer
->it_clock
, p
, &now
);
1254 bump_cpu_timer(timer
, now
);
1255 if (unlikely(p
->exit_state
)) {
1256 clear_dead_task(timer
, now
);
1259 read_lock(&tasklist_lock
); /* arm_timer needs it. */
1261 read_lock(&tasklist_lock
);
1262 if (unlikely(p
->signal
== NULL
)) {
1264 * The process has been reaped.
1265 * We can't even collect a sample any more.
1268 timer
->it
.cpu
.task
= p
= NULL
;
1269 timer
->it
.cpu
.expires
.sched
= 0;
1271 } else if (unlikely(p
->exit_state
) && thread_group_empty(p
)) {
1273 * We've noticed that the thread is dead, but
1274 * not yet reaped. Take this opportunity to
1275 * drop our task ref.
1277 clear_dead_task(timer
, now
);
1280 cpu_timer_sample_group(timer
->it_clock
, p
, &now
);
1281 bump_cpu_timer(timer
, now
);
1282 /* Leave the tasklist_lock locked for the call below. */
1286 * Now re-arm for the new expiry time.
1288 arm_timer(timer
, now
);
1291 read_unlock(&tasklist_lock
);
1294 timer
->it_overrun_last
= timer
->it_overrun
;
1295 timer
->it_overrun
= -1;
1296 ++timer
->it_requeue_pending
;
1300 * task_cputime_zero - Check a task_cputime struct for all zero fields.
1302 * @cputime: The struct to compare.
1304 * Checks @cputime to see if all fields are zero. Returns true if all fields
1305 * are zero, false if any field is nonzero.
1307 static inline int task_cputime_zero(const struct task_cputime
*cputime
)
1309 if (cputime_eq(cputime
->utime
, cputime_zero
) &&
1310 cputime_eq(cputime
->stime
, cputime_zero
) &&
1311 cputime
->sum_exec_runtime
== 0)
1317 * task_cputime_expired - Compare two task_cputime entities.
1319 * @sample: The task_cputime structure to be checked for expiration.
1320 * @expires: Expiration times, against which @sample will be checked.
1322 * Checks @sample against @expires to see if any field of @sample has expired.
1323 * Returns true if any field of the former is greater than the corresponding
1324 * field of the latter if the latter field is set. Otherwise returns false.
1326 static inline int task_cputime_expired(const struct task_cputime
*sample
,
1327 const struct task_cputime
*expires
)
1329 if (!cputime_eq(expires
->utime
, cputime_zero
) &&
1330 cputime_ge(sample
->utime
, expires
->utime
))
1332 if (!cputime_eq(expires
->stime
, cputime_zero
) &&
1333 cputime_ge(cputime_add(sample
->utime
, sample
->stime
),
1336 if (expires
->sum_exec_runtime
!= 0 &&
1337 sample
->sum_exec_runtime
>= expires
->sum_exec_runtime
)
1343 * fastpath_timer_check - POSIX CPU timers fast path.
1345 * @tsk: The task (thread) being checked.
1347 * Check the task and thread group timers. If both are zero (there are no
1348 * timers set) return false. Otherwise snapshot the task and thread group
1349 * timers and compare them with the corresponding expiration times. Return
1350 * true if a timer has expired, else return false.
1352 static inline int fastpath_timer_check(struct task_struct
*tsk
)
1354 struct signal_struct
*sig
;
1356 /* tsk == current, ensure it is safe to use ->signal/sighand */
1357 if (unlikely(tsk
->exit_state
))
1360 if (!task_cputime_zero(&tsk
->cputime_expires
)) {
1361 struct task_cputime task_sample
= {
1362 .utime
= tsk
->utime
,
1363 .stime
= tsk
->stime
,
1364 .sum_exec_runtime
= tsk
->se
.sum_exec_runtime
1367 if (task_cputime_expired(&task_sample
, &tsk
->cputime_expires
))
1372 if (!task_cputime_zero(&sig
->cputime_expires
)) {
1373 struct task_cputime group_sample
;
1375 thread_group_cputimer(tsk
, &group_sample
);
1376 if (task_cputime_expired(&group_sample
, &sig
->cputime_expires
))
1380 return sig
->rlim
[RLIMIT_CPU
].rlim_cur
!= RLIM_INFINITY
;
1384 * This is called from the timer interrupt handler. The irq handler has
1385 * already updated our counts. We need to check if any timers fire now.
1386 * Interrupts are disabled.
1388 void run_posix_cpu_timers(struct task_struct
*tsk
)
1391 struct k_itimer
*timer
, *next
;
1393 BUG_ON(!irqs_disabled());
1396 * The fast path checks that there are no expired thread or thread
1397 * group timers. If that's so, just return.
1399 if (!fastpath_timer_check(tsk
))
1402 spin_lock(&tsk
->sighand
->siglock
);
1404 * Here we take off tsk->signal->cpu_timers[N] and
1405 * tsk->cpu_timers[N] all the timers that are firing, and
1406 * put them on the firing list.
1408 check_thread_timers(tsk
, &firing
);
1409 check_process_timers(tsk
, &firing
);
1412 * We must release these locks before taking any timer's lock.
1413 * There is a potential race with timer deletion here, as the
1414 * siglock now protects our private firing list. We have set
1415 * the firing flag in each timer, so that a deletion attempt
1416 * that gets the timer lock before we do will give it up and
1417 * spin until we've taken care of that timer below.
1419 spin_unlock(&tsk
->sighand
->siglock
);
1422 * Now that all the timers on our list have the firing flag,
1423 * noone will touch their list entries but us. We'll take
1424 * each timer's lock before clearing its firing flag, so no
1425 * timer call will interfere.
1427 list_for_each_entry_safe(timer
, next
, &firing
, it
.cpu
.entry
) {
1430 spin_lock(&timer
->it_lock
);
1431 list_del_init(&timer
->it
.cpu
.entry
);
1432 cpu_firing
= timer
->it
.cpu
.firing
;
1433 timer
->it
.cpu
.firing
= 0;
1435 * The firing flag is -1 if we collided with a reset
1436 * of the timer, which already reported this
1437 * almost-firing as an overrun. So don't generate an event.
1439 if (likely(cpu_firing
>= 0))
1440 cpu_timer_fire(timer
);
1441 spin_unlock(&timer
->it_lock
);
1446 * Set one of the process-wide special case CPU timers.
1447 * The tsk->sighand->siglock must be held by the caller.
1448 * The *newval argument is relative and we update it to be absolute, *oldval
1449 * is absolute and we update it to be relative.
1451 void set_process_cpu_timer(struct task_struct
*tsk
, unsigned int clock_idx
,
1452 cputime_t
*newval
, cputime_t
*oldval
)
1454 union cpu_time_count now
;
1455 struct list_head
*head
;
1457 BUG_ON(clock_idx
== CPUCLOCK_SCHED
);
1458 cpu_timer_sample_group(clock_idx
, tsk
, &now
);
1461 if (!cputime_eq(*oldval
, cputime_zero
)) {
1462 if (cputime_le(*oldval
, now
.cpu
)) {
1463 /* Just about to fire. */
1464 *oldval
= cputime_one_jiffy
;
1466 *oldval
= cputime_sub(*oldval
, now
.cpu
);
1470 if (cputime_eq(*newval
, cputime_zero
))
1472 *newval
= cputime_add(*newval
, now
.cpu
);
1475 * If the RLIMIT_CPU timer will expire before the
1476 * ITIMER_PROF timer, we have nothing else to do.
1478 if (tsk
->signal
->rlim
[RLIMIT_CPU
].rlim_cur
1479 < cputime_to_secs(*newval
))
1484 * Check whether there are any process timers already set to fire
1485 * before this one. If so, we don't have anything more to do.
1487 head
= &tsk
->signal
->cpu_timers
[clock_idx
];
1488 if (list_empty(head
) ||
1489 cputime_ge(list_first_entry(head
,
1490 struct cpu_timer_list
, entry
)->expires
.cpu
,
1492 switch (clock_idx
) {
1494 tsk
->signal
->cputime_expires
.prof_exp
= *newval
;
1497 tsk
->signal
->cputime_expires
.virt_exp
= *newval
;
1503 static int do_cpu_nanosleep(const clockid_t which_clock
, int flags
,
1504 struct timespec
*rqtp
, struct itimerspec
*it
)
1506 struct k_itimer timer
;
1510 * Set up a temporary timer and then wait for it to go off.
1512 memset(&timer
, 0, sizeof timer
);
1513 spin_lock_init(&timer
.it_lock
);
1514 timer
.it_clock
= which_clock
;
1515 timer
.it_overrun
= -1;
1516 error
= posix_cpu_timer_create(&timer
);
1517 timer
.it_process
= current
;
1519 static struct itimerspec zero_it
;
1521 memset(it
, 0, sizeof *it
);
1522 it
->it_value
= *rqtp
;
1524 spin_lock_irq(&timer
.it_lock
);
1525 error
= posix_cpu_timer_set(&timer
, flags
, it
, NULL
);
1527 spin_unlock_irq(&timer
.it_lock
);
1531 while (!signal_pending(current
)) {
1532 if (timer
.it
.cpu
.expires
.sched
== 0) {
1534 * Our timer fired and was reset.
1536 spin_unlock_irq(&timer
.it_lock
);
1541 * Block until cpu_timer_fire (or a signal) wakes us.
1543 __set_current_state(TASK_INTERRUPTIBLE
);
1544 spin_unlock_irq(&timer
.it_lock
);
1546 spin_lock_irq(&timer
.it_lock
);
1550 * We were interrupted by a signal.
1552 sample_to_timespec(which_clock
, timer
.it
.cpu
.expires
, rqtp
);
1553 posix_cpu_timer_set(&timer
, 0, &zero_it
, it
);
1554 spin_unlock_irq(&timer
.it_lock
);
1556 if ((it
->it_value
.tv_sec
| it
->it_value
.tv_nsec
) == 0) {
1558 * It actually did fire already.
1563 error
= -ERESTART_RESTARTBLOCK
;
1569 int posix_cpu_nsleep(const clockid_t which_clock
, int flags
,
1570 struct timespec
*rqtp
, struct timespec __user
*rmtp
)
1572 struct restart_block
*restart_block
=
1573 ¤t_thread_info()->restart_block
;
1574 struct itimerspec it
;
1578 * Diagnose required errors first.
1580 if (CPUCLOCK_PERTHREAD(which_clock
) &&
1581 (CPUCLOCK_PID(which_clock
) == 0 ||
1582 CPUCLOCK_PID(which_clock
) == current
->pid
))
1585 error
= do_cpu_nanosleep(which_clock
, flags
, rqtp
, &it
);
1587 if (error
== -ERESTART_RESTARTBLOCK
) {
1589 if (flags
& TIMER_ABSTIME
)
1590 return -ERESTARTNOHAND
;
1592 * Report back to the user the time still remaining.
1594 if (rmtp
!= NULL
&& copy_to_user(rmtp
, &it
.it_value
, sizeof *rmtp
))
1597 restart_block
->fn
= posix_cpu_nsleep_restart
;
1598 restart_block
->arg0
= which_clock
;
1599 restart_block
->arg1
= (unsigned long) rmtp
;
1600 restart_block
->arg2
= rqtp
->tv_sec
;
1601 restart_block
->arg3
= rqtp
->tv_nsec
;
1606 long posix_cpu_nsleep_restart(struct restart_block
*restart_block
)
1608 clockid_t which_clock
= restart_block
->arg0
;
1609 struct timespec __user
*rmtp
;
1611 struct itimerspec it
;
1614 rmtp
= (struct timespec __user
*) restart_block
->arg1
;
1615 t
.tv_sec
= restart_block
->arg2
;
1616 t
.tv_nsec
= restart_block
->arg3
;
1618 restart_block
->fn
= do_no_restart_syscall
;
1619 error
= do_cpu_nanosleep(which_clock
, TIMER_ABSTIME
, &t
, &it
);
1621 if (error
== -ERESTART_RESTARTBLOCK
) {
1623 * Report back to the user the time still remaining.
1625 if (rmtp
!= NULL
&& copy_to_user(rmtp
, &it
.it_value
, sizeof *rmtp
))
1628 restart_block
->fn
= posix_cpu_nsleep_restart
;
1629 restart_block
->arg0
= which_clock
;
1630 restart_block
->arg1
= (unsigned long) rmtp
;
1631 restart_block
->arg2
= t
.tv_sec
;
1632 restart_block
->arg3
= t
.tv_nsec
;
1639 #define PROCESS_CLOCK MAKE_PROCESS_CPUCLOCK(0, CPUCLOCK_SCHED)
1640 #define THREAD_CLOCK MAKE_THREAD_CPUCLOCK(0, CPUCLOCK_SCHED)
1642 static int process_cpu_clock_getres(const clockid_t which_clock
,
1643 struct timespec
*tp
)
1645 return posix_cpu_clock_getres(PROCESS_CLOCK
, tp
);
1647 static int process_cpu_clock_get(const clockid_t which_clock
,
1648 struct timespec
*tp
)
1650 return posix_cpu_clock_get(PROCESS_CLOCK
, tp
);
1652 static int process_cpu_timer_create(struct k_itimer
*timer
)
1654 timer
->it_clock
= PROCESS_CLOCK
;
1655 return posix_cpu_timer_create(timer
);
1657 static int process_cpu_nsleep(const clockid_t which_clock
, int flags
,
1658 struct timespec
*rqtp
,
1659 struct timespec __user
*rmtp
)
1661 return posix_cpu_nsleep(PROCESS_CLOCK
, flags
, rqtp
, rmtp
);
1663 static long process_cpu_nsleep_restart(struct restart_block
*restart_block
)
1667 static int thread_cpu_clock_getres(const clockid_t which_clock
,
1668 struct timespec
*tp
)
1670 return posix_cpu_clock_getres(THREAD_CLOCK
, tp
);
1672 static int thread_cpu_clock_get(const clockid_t which_clock
,
1673 struct timespec
*tp
)
1675 return posix_cpu_clock_get(THREAD_CLOCK
, tp
);
1677 static int thread_cpu_timer_create(struct k_itimer
*timer
)
1679 timer
->it_clock
= THREAD_CLOCK
;
1680 return posix_cpu_timer_create(timer
);
1682 static int thread_cpu_nsleep(const clockid_t which_clock
, int flags
,
1683 struct timespec
*rqtp
, struct timespec __user
*rmtp
)
1687 static long thread_cpu_nsleep_restart(struct restart_block
*restart_block
)
1692 static __init
int init_posix_cpu_timers(void)
1694 struct k_clock process
= {
1695 .clock_getres
= process_cpu_clock_getres
,
1696 .clock_get
= process_cpu_clock_get
,
1697 .clock_set
= do_posix_clock_nosettime
,
1698 .timer_create
= process_cpu_timer_create
,
1699 .nsleep
= process_cpu_nsleep
,
1700 .nsleep_restart
= process_cpu_nsleep_restart
,
1702 struct k_clock thread
= {
1703 .clock_getres
= thread_cpu_clock_getres
,
1704 .clock_get
= thread_cpu_clock_get
,
1705 .clock_set
= do_posix_clock_nosettime
,
1706 .timer_create
= thread_cpu_timer_create
,
1707 .nsleep
= thread_cpu_nsleep
,
1708 .nsleep_restart
= thread_cpu_nsleep_restart
,
1712 register_posix_clock(CLOCK_PROCESS_CPUTIME_ID
, &process
);
1713 register_posix_clock(CLOCK_THREAD_CPUTIME_ID
, &thread
);
1715 cputime_to_timespec(cputime_one_jiffy
, &ts
);
1716 onecputick
= ts
.tv_nsec
;
1717 WARN_ON(ts
.tv_sec
!= 0);
1721 __initcall(init_posix_cpu_timers
);