2 * linux/kernel/posix-timers.c
5 * 2002-10-15 Posix Clocks & timers
6 * by George Anzinger george@mvista.com
8 * Copyright (C) 2002 2003 by MontaVista Software.
10 * 2004-06-01 Fix CLOCK_REALTIME clock/timer TIMER_ABSTIME bug.
11 * Copyright (C) 2004 Boris Hu
13 * This program is free software; you can redistribute it and/or modify
14 * it under the terms of the GNU General Public License as published by
15 * the Free Software Foundation; either version 2 of the License, or (at
16 * your option) any later version.
18 * This program is distributed in the hope that it will be useful, but
19 * WITHOUT ANY WARRANTY; without even the implied warranty of
20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
21 * General Public License for more details.
23 * You should have received a copy of the GNU General Public License
24 * along with this program; if not, write to the Free Software
25 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
27 * MontaVista Software | 1237 East Arques Avenue | Sunnyvale | CA 94085 | USA
30 /* These are all the functions necessary to implement
31 * POSIX clocks & timers
34 #include <linux/interrupt.h>
35 #include <linux/slab.h>
36 #include <linux/time.h>
37 #include <linux/mutex.h>
39 #include <asm/uaccess.h>
40 #include <linux/list.h>
41 #include <linux/init.h>
42 #include <linux/compiler.h>
43 #include <linux/idr.h>
44 #include <linux/posix-timers.h>
45 #include <linux/syscalls.h>
46 #include <linux/wait.h>
47 #include <linux/workqueue.h>
48 #include <linux/module.h>
51 * Management arrays for POSIX timers. Timers are kept in slab memory
52 * Timer ids are allocated by an external routine that keeps track of the
53 * id and the timer. The external interface is:
55 * void *idr_find(struct idr *idp, int id); to find timer_id <id>
56 * int idr_get_new(struct idr *idp, void *ptr); to get a new id and
58 * void idr_remove(struct idr *idp, int id); to release <id>
59 * void idr_init(struct idr *idp); to initialize <idp>
61 * The idr_get_new *may* call slab for more memory so it must not be
62 * called under a spin lock. Likewise idr_remore may release memory
63 * (but it may be ok to do this under a lock...).
64 * idr_find is just a memory look up and is quite fast. A -1 return
65 * indicates that the requested id does not exist.
69 * Lets keep our timers in a slab cache :-)
71 static struct kmem_cache
*posix_timers_cache
;
72 static struct idr posix_timers_id
;
73 static DEFINE_SPINLOCK(idr_lock
);
76 * we assume that the new SIGEV_THREAD_ID shares no bits with the other
77 * SIGEV values. Here we put out an error if this assumption fails.
79 #if SIGEV_THREAD_ID != (SIGEV_THREAD_ID & \
80 ~(SIGEV_SIGNAL | SIGEV_NONE | SIGEV_THREAD))
81 #error "SIGEV_THREAD_ID must not share bit with other SIGEV values!"
86 * The timer ID is turned into a timer address by idr_find().
87 * Verifying a valid ID consists of:
89 * a) checking that idr_find() returns other than -1.
90 * b) checking that the timer id matches the one in the timer itself.
91 * c) that the timer owner is in the callers thread group.
95 * CLOCKs: The POSIX standard calls for a couple of clocks and allows us
96 * to implement others. This structure defines the various
97 * clocks and allows the possibility of adding others. We
98 * provide an interface to add clocks to the table and expect
99 * the "arch" code to add at least one clock that is high
100 * resolution. Here we define the standard CLOCK_REALTIME as a
101 * 1/HZ resolution clock.
103 * RESOLUTION: Clock resolution is used to round up timer and interval
104 * times, NOT to report clock times, which are reported with as
105 * much resolution as the system can muster. In some cases this
106 * resolution may depend on the underlying clock hardware and
107 * may not be quantifiable until run time, and only then is the
108 * necessary code is written. The standard says we should say
109 * something about this issue in the documentation...
111 * FUNCTIONS: The CLOCKs structure defines possible functions to handle
112 * various clock functions. For clocks that use the standard
113 * system timer code these entries should be NULL. This will
114 * allow dispatch without the overhead of indirect function
115 * calls. CLOCKS that depend on other sources (e.g. WWV or GPS)
116 * must supply functions here, even if the function just returns
117 * ENOSYS. The standard POSIX timer management code assumes the
118 * following: 1.) The k_itimer struct (sched.h) is used for the
119 * timer. 2.) The list, it_lock, it_clock, it_id and it_process
120 * fields are not modified by timer code.
122 * At this time all functions EXCEPT clock_nanosleep can be
123 * redirected by the CLOCKS structure. Clock_nanosleep is in
124 * there, but the code ignores it.
126 * Permissions: It is assumed that the clock_settime() function defined
127 * for each clock will take care of permission checks. Some
128 * clocks may be set able by any user (i.e. local process
129 * clocks) others not. Currently the only set able clock we
130 * have is CLOCK_REALTIME and its high res counter part, both of
131 * which we beg off on and pass to do_sys_settimeofday().
134 static struct k_clock posix_clocks
[MAX_CLOCKS
];
137 * These ones are defined below.
139 static int common_nsleep(const clockid_t
, int flags
, struct timespec
*t
,
140 struct timespec __user
*rmtp
);
141 static void common_timer_get(struct k_itimer
*, struct itimerspec
*);
142 static int common_timer_set(struct k_itimer
*, int,
143 struct itimerspec
*, struct itimerspec
*);
144 static int common_timer_del(struct k_itimer
*timer
);
146 static enum hrtimer_restart
posix_timer_fn(struct hrtimer
*data
);
148 static struct k_itimer
*lock_timer(timer_t timer_id
, unsigned long *flags
);
150 static inline void unlock_timer(struct k_itimer
*timr
, unsigned long flags
)
152 spin_unlock_irqrestore(&timr
->it_lock
, flags
);
156 * Call the k_clock hook function if non-null, or the default function.
158 #define CLOCK_DISPATCH(clock, call, arglist) \
159 ((clock) < 0 ? posix_cpu_##call arglist : \
160 (posix_clocks[clock].call != NULL \
161 ? (*posix_clocks[clock].call) arglist : common_##call arglist))
164 * Default clock hook functions when the struct k_clock passed
165 * to register_posix_clock leaves a function pointer null.
167 * The function common_CALL is the default implementation for
168 * the function pointer CALL in struct k_clock.
171 static inline int common_clock_getres(const clockid_t which_clock
,
175 tp
->tv_nsec
= posix_clocks
[which_clock
].res
;
180 * Get real time for posix timers
182 static int common_clock_get(clockid_t which_clock
, struct timespec
*tp
)
184 ktime_get_real_ts(tp
);
188 static inline int common_clock_set(const clockid_t which_clock
,
191 return do_sys_settimeofday(tp
, NULL
);
194 static int common_timer_create(struct k_itimer
*new_timer
)
196 hrtimer_init(&new_timer
->it
.real
.timer
, new_timer
->it_clock
, 0);
201 * Return nonzero if we know a priori this clockid_t value is bogus.
203 static inline int invalid_clockid(const clockid_t which_clock
)
205 if (which_clock
< 0) /* CPU clock, posix_cpu_* will check it */
207 if ((unsigned) which_clock
>= MAX_CLOCKS
)
209 if (posix_clocks
[which_clock
].clock_getres
!= NULL
)
211 if (posix_clocks
[which_clock
].res
!= 0)
217 * Get monotonic time for posix timers
219 static int posix_ktime_get_ts(clockid_t which_clock
, struct timespec
*tp
)
226 * Initialize everything, well, just everything in Posix clocks/timers ;)
228 static __init
int init_posix_timers(void)
230 struct k_clock clock_realtime
= {
231 .clock_getres
= hrtimer_get_res
,
233 struct k_clock clock_monotonic
= {
234 .clock_getres
= hrtimer_get_res
,
235 .clock_get
= posix_ktime_get_ts
,
236 .clock_set
= do_posix_clock_nosettime
,
239 register_posix_clock(CLOCK_REALTIME
, &clock_realtime
);
240 register_posix_clock(CLOCK_MONOTONIC
, &clock_monotonic
);
242 posix_timers_cache
= kmem_cache_create("posix_timers_cache",
243 sizeof (struct k_itimer
), 0, SLAB_PANIC
,
245 idr_init(&posix_timers_id
);
249 __initcall(init_posix_timers
);
251 static void schedule_next_timer(struct k_itimer
*timr
)
253 struct hrtimer
*timer
= &timr
->it
.real
.timer
;
255 if (timr
->it
.real
.interval
.tv64
== 0)
258 timr
->it_overrun
+= (unsigned int) hrtimer_forward(timer
,
259 timer
->base
->get_time(),
260 timr
->it
.real
.interval
);
262 timr
->it_overrun_last
= timr
->it_overrun
;
263 timr
->it_overrun
= -1;
264 ++timr
->it_requeue_pending
;
265 hrtimer_restart(timer
);
269 * This function is exported for use by the signal deliver code. It is
270 * called just prior to the info block being released and passes that
271 * block to us. It's function is to update the overrun entry AND to
272 * restart the timer. It should only be called if the timer is to be
273 * restarted (i.e. we have flagged this in the sys_private entry of the
276 * To protect aginst the timer going away while the interrupt is queued,
277 * we require that the it_requeue_pending flag be set.
279 void do_schedule_next_timer(struct siginfo
*info
)
281 struct k_itimer
*timr
;
284 timr
= lock_timer(info
->si_tid
, &flags
);
286 if (timr
&& timr
->it_requeue_pending
== info
->si_sys_private
) {
287 if (timr
->it_clock
< 0)
288 posix_cpu_timer_schedule(timr
);
290 schedule_next_timer(timr
);
292 info
->si_overrun
+= timr
->it_overrun_last
;
296 unlock_timer(timr
, flags
);
299 int posix_timer_event(struct k_itimer
*timr
, int si_private
)
303 * FIXME: if ->sigq is queued we can race with
304 * dequeue_signal()->do_schedule_next_timer().
306 * If dequeue_signal() sees the "right" value of
307 * si_sys_private it calls do_schedule_next_timer().
308 * We re-queue ->sigq and drop ->it_lock().
309 * do_schedule_next_timer() locks the timer
310 * and re-schedules it while ->sigq is pending.
311 * Not really bad, but not that we want.
313 timr
->sigq
->info
.si_sys_private
= si_private
;
315 shared
= !(timr
->it_sigev_notify
& SIGEV_THREAD_ID
);
316 ret
= send_sigqueue(timr
->sigq
, timr
->it_process
, shared
);
317 /* If we failed to send the signal the timer stops. */
320 EXPORT_SYMBOL_GPL(posix_timer_event
);
323 * This function gets called when a POSIX.1b interval timer expires. It
324 * is used as a callback from the kernel internal timer. The
325 * run_timer_list code ALWAYS calls with interrupts on.
327 * This code is for CLOCK_REALTIME* and CLOCK_MONOTONIC* timers.
329 static enum hrtimer_restart
posix_timer_fn(struct hrtimer
*timer
)
331 struct k_itimer
*timr
;
334 enum hrtimer_restart ret
= HRTIMER_NORESTART
;
336 timr
= container_of(timer
, struct k_itimer
, it
.real
.timer
);
337 spin_lock_irqsave(&timr
->it_lock
, flags
);
339 if (timr
->it
.real
.interval
.tv64
!= 0)
340 si_private
= ++timr
->it_requeue_pending
;
342 if (posix_timer_event(timr
, si_private
)) {
344 * signal was not sent because of sig_ignor
345 * we will not get a call back to restart it AND
346 * it should be restarted.
348 if (timr
->it
.real
.interval
.tv64
!= 0) {
349 ktime_t now
= hrtimer_cb_get_time(timer
);
352 * FIXME: What we really want, is to stop this
353 * timer completely and restart it in case the
354 * SIG_IGN is removed. This is a non trivial
355 * change which involves sighand locking
356 * (sigh !), which we don't want to do late in
359 * For now we just let timers with an interval
360 * less than a jiffie expire every jiffie to
361 * avoid softirq starvation in case of SIG_IGN
362 * and a very small interval, which would put
363 * the timer right back on the softirq pending
364 * list. By moving now ahead of time we trick
365 * hrtimer_forward() to expire the timer
366 * later, while we still maintain the overrun
367 * accuracy, but have some inconsistency in
368 * the timer_gettime() case. This is at least
369 * better than a starved softirq. A more
370 * complex fix which solves also another related
371 * inconsistency is already in the pipeline.
373 #ifdef CONFIG_HIGH_RES_TIMERS
375 ktime_t kj
= ktime_set(0, NSEC_PER_SEC
/ HZ
);
377 if (timr
->it
.real
.interval
.tv64
< kj
.tv64
)
378 now
= ktime_add(now
, kj
);
381 timr
->it_overrun
+= (unsigned int)
382 hrtimer_forward(timer
, now
,
383 timr
->it
.real
.interval
);
384 ret
= HRTIMER_RESTART
;
385 ++timr
->it_requeue_pending
;
389 unlock_timer(timr
, flags
);
393 static struct task_struct
* good_sigevent(sigevent_t
* event
)
395 struct task_struct
*rtn
= current
->group_leader
;
397 if ((event
->sigev_notify
& SIGEV_THREAD_ID
) &&
398 (!(rtn
= find_task_by_vpid(event
->sigev_notify_thread_id
)) ||
399 !same_thread_group(rtn
, current
) ||
400 (event
->sigev_notify
& ~SIGEV_THREAD_ID
) != SIGEV_SIGNAL
))
403 if (((event
->sigev_notify
& ~SIGEV_THREAD_ID
) != SIGEV_NONE
) &&
404 ((event
->sigev_signo
<= 0) || (event
->sigev_signo
> SIGRTMAX
)))
410 void register_posix_clock(const clockid_t clock_id
, struct k_clock
*new_clock
)
412 if ((unsigned) clock_id
>= MAX_CLOCKS
) {
413 printk("POSIX clock register failed for clock_id %d\n",
418 posix_clocks
[clock_id
] = *new_clock
;
420 EXPORT_SYMBOL_GPL(register_posix_clock
);
422 static struct k_itimer
* alloc_posix_timer(void)
424 struct k_itimer
*tmr
;
425 tmr
= kmem_cache_zalloc(posix_timers_cache
, GFP_KERNEL
);
428 if (unlikely(!(tmr
->sigq
= sigqueue_alloc()))) {
429 kmem_cache_free(posix_timers_cache
, tmr
);
432 memset(&tmr
->sigq
->info
, 0, sizeof(siginfo_t
));
437 #define IT_ID_NOT_SET 0
438 static void release_posix_timer(struct k_itimer
*tmr
, int it_id_set
)
442 spin_lock_irqsave(&idr_lock
, flags
);
443 idr_remove(&posix_timers_id
, tmr
->it_id
);
444 spin_unlock_irqrestore(&idr_lock
, flags
);
446 sigqueue_free(tmr
->sigq
);
447 kmem_cache_free(posix_timers_cache
, tmr
);
450 /* Create a POSIX.1b interval timer. */
453 sys_timer_create(const clockid_t which_clock
,
454 struct sigevent __user
*timer_event_spec
,
455 timer_t __user
* created_timer_id
)
457 struct k_itimer
*new_timer
;
458 int error
, new_timer_id
;
459 struct task_struct
*process
;
461 int it_id_set
= IT_ID_NOT_SET
;
463 if (invalid_clockid(which_clock
))
466 new_timer
= alloc_posix_timer();
467 if (unlikely(!new_timer
))
470 spin_lock_init(&new_timer
->it_lock
);
472 if (unlikely(!idr_pre_get(&posix_timers_id
, GFP_KERNEL
))) {
476 spin_lock_irq(&idr_lock
);
477 error
= idr_get_new(&posix_timers_id
, (void *) new_timer
,
479 spin_unlock_irq(&idr_lock
);
481 if (error
== -EAGAIN
)
484 * Weird looking, but we return EAGAIN if the IDR is
485 * full (proper POSIX return value for this)
491 it_id_set
= IT_ID_SET
;
492 new_timer
->it_id
= (timer_t
) new_timer_id
;
493 new_timer
->it_clock
= which_clock
;
494 new_timer
->it_overrun
= -1;
495 error
= CLOCK_DISPATCH(which_clock
, timer_create
, (new_timer
));
500 * return the timer_id now. The next step is hard to
501 * back out if there is an error.
503 if (copy_to_user(created_timer_id
,
504 &new_timer_id
, sizeof (new_timer_id
))) {
508 if (timer_event_spec
) {
509 if (copy_from_user(&event
, timer_event_spec
, sizeof (event
))) {
514 process
= good_sigevent(&event
);
516 get_task_struct(process
);
523 event
.sigev_notify
= SIGEV_SIGNAL
;
524 event
.sigev_signo
= SIGALRM
;
525 event
.sigev_value
.sival_int
= new_timer
->it_id
;
526 process
= current
->group_leader
;
527 get_task_struct(process
);
530 new_timer
->it_sigev_notify
= event
.sigev_notify
;
531 new_timer
->sigq
->info
.si_signo
= event
.sigev_signo
;
532 new_timer
->sigq
->info
.si_value
= event
.sigev_value
;
533 new_timer
->sigq
->info
.si_tid
= new_timer
->it_id
;
534 new_timer
->sigq
->info
.si_code
= SI_TIMER
;
536 spin_lock_irq(¤t
->sighand
->siglock
);
537 new_timer
->it_process
= process
;
538 list_add(&new_timer
->list
, ¤t
->signal
->posix_timers
);
539 spin_unlock_irq(¤t
->sighand
->siglock
);
543 * In the case of the timer belonging to another task, after
544 * the task is unlocked, the timer is owned by the other task
545 * and may cease to exist at any time. Don't use or modify
546 * new_timer after the unlock call.
549 release_posix_timer(new_timer
, it_id_set
);
554 * Locking issues: We need to protect the result of the id look up until
555 * we get the timer locked down so it is not deleted under us. The
556 * removal is done under the idr spinlock so we use that here to bridge
557 * the find to the timer lock. To avoid a dead lock, the timer id MUST
558 * be release with out holding the timer lock.
560 static struct k_itimer
* lock_timer(timer_t timer_id
, unsigned long *flags
)
562 struct k_itimer
*timr
;
564 * Watch out here. We do a irqsave on the idr_lock and pass the
565 * flags part over to the timer lock. Must not let interrupts in
566 * while we are moving the lock.
569 spin_lock_irqsave(&idr_lock
, *flags
);
570 timr
= (struct k_itimer
*) idr_find(&posix_timers_id
, (int) timer_id
);
572 spin_lock(&timr
->it_lock
);
574 if ((timr
->it_id
!= timer_id
) || !(timr
->it_process
) ||
575 !same_thread_group(timr
->it_process
, current
)) {
576 spin_unlock(&timr
->it_lock
);
577 spin_unlock_irqrestore(&idr_lock
, *flags
);
580 spin_unlock(&idr_lock
);
582 spin_unlock_irqrestore(&idr_lock
, *flags
);
588 * Get the time remaining on a POSIX.1b interval timer. This function
589 * is ALWAYS called with spin_lock_irq on the timer, thus it must not
592 * We have a couple of messes to clean up here. First there is the case
593 * of a timer that has a requeue pending. These timers should appear to
594 * be in the timer list with an expiry as if we were to requeue them
597 * The second issue is the SIGEV_NONE timer which may be active but is
598 * not really ever put in the timer list (to save system resources).
599 * This timer may be expired, and if so, we will do it here. Otherwise
600 * it is the same as a requeue pending timer WRT to what we should
604 common_timer_get(struct k_itimer
*timr
, struct itimerspec
*cur_setting
)
606 ktime_t now
, remaining
, iv
;
607 struct hrtimer
*timer
= &timr
->it
.real
.timer
;
609 memset(cur_setting
, 0, sizeof(struct itimerspec
));
611 iv
= timr
->it
.real
.interval
;
613 /* interval timer ? */
615 cur_setting
->it_interval
= ktime_to_timespec(iv
);
616 else if (!hrtimer_active(timer
) &&
617 (timr
->it_sigev_notify
& ~SIGEV_THREAD_ID
) != SIGEV_NONE
)
620 now
= timer
->base
->get_time();
623 * When a requeue is pending or this is a SIGEV_NONE
624 * timer move the expiry time forward by intervals, so
627 if (iv
.tv64
&& (timr
->it_requeue_pending
& REQUEUE_PENDING
||
628 (timr
->it_sigev_notify
& ~SIGEV_THREAD_ID
) == SIGEV_NONE
))
629 timr
->it_overrun
+= (unsigned int) hrtimer_forward(timer
, now
, iv
);
631 remaining
= ktime_sub(timer
->expires
, now
);
632 /* Return 0 only, when the timer is expired and not pending */
633 if (remaining
.tv64
<= 0) {
635 * A single shot SIGEV_NONE timer must return 0, when
638 if ((timr
->it_sigev_notify
& ~SIGEV_THREAD_ID
) != SIGEV_NONE
)
639 cur_setting
->it_value
.tv_nsec
= 1;
641 cur_setting
->it_value
= ktime_to_timespec(remaining
);
644 /* Get the time remaining on a POSIX.1b interval timer. */
646 sys_timer_gettime(timer_t timer_id
, struct itimerspec __user
*setting
)
648 struct k_itimer
*timr
;
649 struct itimerspec cur_setting
;
652 timr
= lock_timer(timer_id
, &flags
);
656 CLOCK_DISPATCH(timr
->it_clock
, timer_get
, (timr
, &cur_setting
));
658 unlock_timer(timr
, flags
);
660 if (copy_to_user(setting
, &cur_setting
, sizeof (cur_setting
)))
667 * Get the number of overruns of a POSIX.1b interval timer. This is to
668 * be the overrun of the timer last delivered. At the same time we are
669 * accumulating overruns on the next timer. The overrun is frozen when
670 * the signal is delivered, either at the notify time (if the info block
671 * is not queued) or at the actual delivery time (as we are informed by
672 * the call back to do_schedule_next_timer(). So all we need to do is
673 * to pick up the frozen overrun.
676 sys_timer_getoverrun(timer_t timer_id
)
678 struct k_itimer
*timr
;
682 timr
= lock_timer(timer_id
, &flags
);
686 overrun
= timr
->it_overrun_last
;
687 unlock_timer(timr
, flags
);
692 /* Set a POSIX.1b interval timer. */
693 /* timr->it_lock is taken. */
695 common_timer_set(struct k_itimer
*timr
, int flags
,
696 struct itimerspec
*new_setting
, struct itimerspec
*old_setting
)
698 struct hrtimer
*timer
= &timr
->it
.real
.timer
;
699 enum hrtimer_mode mode
;
702 common_timer_get(timr
, old_setting
);
704 /* disable the timer */
705 timr
->it
.real
.interval
.tv64
= 0;
707 * careful here. If smp we could be in the "fire" routine which will
708 * be spinning as we hold the lock. But this is ONLY an SMP issue.
710 if (hrtimer_try_to_cancel(timer
) < 0)
713 timr
->it_requeue_pending
= (timr
->it_requeue_pending
+ 2) &
715 timr
->it_overrun_last
= 0;
717 /* switch off the timer when it_value is zero */
718 if (!new_setting
->it_value
.tv_sec
&& !new_setting
->it_value
.tv_nsec
)
721 mode
= flags
& TIMER_ABSTIME
? HRTIMER_MODE_ABS
: HRTIMER_MODE_REL
;
722 hrtimer_init(&timr
->it
.real
.timer
, timr
->it_clock
, mode
);
723 timr
->it
.real
.timer
.function
= posix_timer_fn
;
725 timer
->expires
= timespec_to_ktime(new_setting
->it_value
);
727 /* Convert interval */
728 timr
->it
.real
.interval
= timespec_to_ktime(new_setting
->it_interval
);
730 /* SIGEV_NONE timers are not queued ! See common_timer_get */
731 if (((timr
->it_sigev_notify
& ~SIGEV_THREAD_ID
) == SIGEV_NONE
)) {
732 /* Setup correct expiry time for relative timers */
733 if (mode
== HRTIMER_MODE_REL
) {
735 ktime_add_safe(timer
->expires
,
736 timer
->base
->get_time());
741 hrtimer_start(timer
, timer
->expires
, mode
);
745 /* Set a POSIX.1b interval timer */
747 sys_timer_settime(timer_t timer_id
, int flags
,
748 const struct itimerspec __user
*new_setting
,
749 struct itimerspec __user
*old_setting
)
751 struct k_itimer
*timr
;
752 struct itimerspec new_spec
, old_spec
;
755 struct itimerspec
*rtn
= old_setting
? &old_spec
: NULL
;
760 if (copy_from_user(&new_spec
, new_setting
, sizeof (new_spec
)))
763 if (!timespec_valid(&new_spec
.it_interval
) ||
764 !timespec_valid(&new_spec
.it_value
))
767 timr
= lock_timer(timer_id
, &flag
);
771 error
= CLOCK_DISPATCH(timr
->it_clock
, timer_set
,
772 (timr
, flags
, &new_spec
, rtn
));
774 unlock_timer(timr
, flag
);
775 if (error
== TIMER_RETRY
) {
776 rtn
= NULL
; // We already got the old time...
780 if (old_setting
&& !error
&&
781 copy_to_user(old_setting
, &old_spec
, sizeof (old_spec
)))
787 static inline int common_timer_del(struct k_itimer
*timer
)
789 timer
->it
.real
.interval
.tv64
= 0;
791 if (hrtimer_try_to_cancel(&timer
->it
.real
.timer
) < 0)
796 static inline int timer_delete_hook(struct k_itimer
*timer
)
798 return CLOCK_DISPATCH(timer
->it_clock
, timer_del
, (timer
));
801 /* Delete a POSIX.1b interval timer. */
803 sys_timer_delete(timer_t timer_id
)
805 struct k_itimer
*timer
;
809 timer
= lock_timer(timer_id
, &flags
);
813 if (timer_delete_hook(timer
) == TIMER_RETRY
) {
814 unlock_timer(timer
, flags
);
818 spin_lock(¤t
->sighand
->siglock
);
819 list_del(&timer
->list
);
820 spin_unlock(¤t
->sighand
->siglock
);
822 * This keeps any tasks waiting on the spin lock from thinking
823 * they got something (see the lock code above).
825 put_task_struct(timer
->it_process
);
826 timer
->it_process
= NULL
;
828 unlock_timer(timer
, flags
);
829 release_posix_timer(timer
, IT_ID_SET
);
834 * return timer owned by the process, used by exit_itimers
836 static void itimer_delete(struct k_itimer
*timer
)
841 spin_lock_irqsave(&timer
->it_lock
, flags
);
843 if (timer_delete_hook(timer
) == TIMER_RETRY
) {
844 unlock_timer(timer
, flags
);
847 list_del(&timer
->list
);
849 * This keeps any tasks waiting on the spin lock from thinking
850 * they got something (see the lock code above).
852 put_task_struct(timer
->it_process
);
853 timer
->it_process
= NULL
;
855 unlock_timer(timer
, flags
);
856 release_posix_timer(timer
, IT_ID_SET
);
860 * This is called by do_exit or de_thread, only when there are no more
861 * references to the shared signal_struct.
863 void exit_itimers(struct signal_struct
*sig
)
865 struct k_itimer
*tmr
;
867 while (!list_empty(&sig
->posix_timers
)) {
868 tmr
= list_entry(sig
->posix_timers
.next
, struct k_itimer
, list
);
873 /* Not available / possible... functions */
874 int do_posix_clock_nosettime(const clockid_t clockid
, struct timespec
*tp
)
878 EXPORT_SYMBOL_GPL(do_posix_clock_nosettime
);
880 int do_posix_clock_nonanosleep(const clockid_t clock
, int flags
,
881 struct timespec
*t
, struct timespec __user
*r
)
884 return -EOPNOTSUPP
; /* aka ENOTSUP in userland for POSIX */
885 #else /* parisc does define it separately. */
889 EXPORT_SYMBOL_GPL(do_posix_clock_nonanosleep
);
891 asmlinkage
long sys_clock_settime(const clockid_t which_clock
,
892 const struct timespec __user
*tp
)
894 struct timespec new_tp
;
896 if (invalid_clockid(which_clock
))
898 if (copy_from_user(&new_tp
, tp
, sizeof (*tp
)))
901 return CLOCK_DISPATCH(which_clock
, clock_set
, (which_clock
, &new_tp
));
905 sys_clock_gettime(const clockid_t which_clock
, struct timespec __user
*tp
)
907 struct timespec kernel_tp
;
910 if (invalid_clockid(which_clock
))
912 error
= CLOCK_DISPATCH(which_clock
, clock_get
,
913 (which_clock
, &kernel_tp
));
914 if (!error
&& copy_to_user(tp
, &kernel_tp
, sizeof (kernel_tp
)))
922 sys_clock_getres(const clockid_t which_clock
, struct timespec __user
*tp
)
924 struct timespec rtn_tp
;
927 if (invalid_clockid(which_clock
))
930 error
= CLOCK_DISPATCH(which_clock
, clock_getres
,
931 (which_clock
, &rtn_tp
));
933 if (!error
&& tp
&& copy_to_user(tp
, &rtn_tp
, sizeof (rtn_tp
))) {
941 * nanosleep for monotonic and realtime clocks
943 static int common_nsleep(const clockid_t which_clock
, int flags
,
944 struct timespec
*tsave
, struct timespec __user
*rmtp
)
946 return hrtimer_nanosleep(tsave
, rmtp
, flags
& TIMER_ABSTIME
?
947 HRTIMER_MODE_ABS
: HRTIMER_MODE_REL
,
952 sys_clock_nanosleep(const clockid_t which_clock
, int flags
,
953 const struct timespec __user
*rqtp
,
954 struct timespec __user
*rmtp
)
958 if (invalid_clockid(which_clock
))
961 if (copy_from_user(&t
, rqtp
, sizeof (struct timespec
)))
964 if (!timespec_valid(&t
))
967 return CLOCK_DISPATCH(which_clock
, nsleep
,
968 (which_clock
, flags
, &t
, rmtp
));
972 * nanosleep_restart for monotonic and realtime clocks
974 static int common_nsleep_restart(struct restart_block
*restart_block
)
976 return hrtimer_nanosleep_restart(restart_block
);
980 * This will restart clock_nanosleep. This is required only by
981 * compat_clock_nanosleep_restart for now.
984 clock_nanosleep_restart(struct restart_block
*restart_block
)
986 clockid_t which_clock
= restart_block
->arg0
;
988 return CLOCK_DISPATCH(which_clock
, nsleep_restart
,