2 * Copyright (c) 1999,2000,2001 Jonathan Lemon <jlemon@FreeBSD.org>
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * $FreeBSD: src/sys/kern/kern_event.c,v 1.2.2.10 2004/04/04 07:03:14 cperciva Exp $
29 #include <sys/param.h>
30 #include <sys/systm.h>
31 #include <sys/kernel.h>
33 #include <sys/malloc.h>
34 #include <sys/unistd.h>
37 #include <sys/fcntl.h>
38 #include <sys/queue.h>
39 #include <sys/event.h>
40 #include <sys/eventvar.h>
41 #include <sys/protosw.h>
42 #include <sys/socket.h>
43 #include <sys/socketvar.h>
45 #include <sys/sysctl.h>
46 #include <sys/sysproto.h>
47 #include <sys/thread.h>
49 #include <sys/signalvar.h>
50 #include <sys/filio.h>
53 #include <sys/thread2.h>
54 #include <sys/file2.h>
55 #include <sys/mplock2.h>
57 #define EVENT_REGISTER 1
58 #define EVENT_PROCESS 2
60 MALLOC_DEFINE(M_KQUEUE, "kqueue", "memory for kqueue system");
62 struct kevent_copyin_args {
63 struct kevent_args *ka;
67 #define KNOTE_CACHE_MAX 8
69 struct knote_cache_list {
70 struct klist knote_cache;
74 static int kqueue_scan(struct kqueue *kq, struct kevent *kevp, int count,
75 struct knote *marker);
76 static int kqueue_read(struct file *fp, struct uio *uio,
77 struct ucred *cred, int flags);
78 static int kqueue_write(struct file *fp, struct uio *uio,
79 struct ucred *cred, int flags);
80 static int kqueue_ioctl(struct file *fp, u_long com, caddr_t data,
81 struct ucred *cred, struct sysmsg *msg);
82 static int kqueue_kqfilter(struct file *fp, struct knote *kn);
83 static int kqueue_stat(struct file *fp, struct stat *st,
85 static int kqueue_close(struct file *fp);
86 static void kqueue_wakeup(struct kqueue *kq);
87 static int filter_attach(struct knote *kn);
88 static int filter_event(struct knote *kn, long hint);
93 static struct fileops kqueueops = {
94 .fo_read = kqueue_read,
95 .fo_write = kqueue_write,
96 .fo_ioctl = kqueue_ioctl,
97 .fo_kqfilter = kqueue_kqfilter,
98 .fo_stat = kqueue_stat,
99 .fo_close = kqueue_close,
100 .fo_shutdown = nofo_shutdown
103 static void knote_attach(struct knote *kn);
104 static void knote_drop(struct knote *kn);
105 static void knote_detach_and_drop(struct knote *kn);
106 static void knote_enqueue(struct knote *kn);
107 static void knote_dequeue(struct knote *kn);
108 static struct knote *knote_alloc(void);
109 static void knote_free(struct knote *kn);
111 static void precise_sleep_intr(systimer_t info, int in_ipi,
112 struct intrframe *frame);
113 static int precise_sleep(void *ident, int flags, const char *wmesg,
116 static void filt_kqdetach(struct knote *kn);
117 static int filt_kqueue(struct knote *kn, long hint);
118 static int filt_procattach(struct knote *kn);
119 static void filt_procdetach(struct knote *kn);
120 static int filt_proc(struct knote *kn, long hint);
121 static int filt_fileattach(struct knote *kn);
122 static void filt_timerexpire(void *knx);
123 static int filt_timerattach(struct knote *kn);
124 static void filt_timerdetach(struct knote *kn);
125 static int filt_timer(struct knote *kn, long hint);
126 static int filt_userattach(struct knote *kn);
127 static void filt_userdetach(struct knote *kn);
128 static int filt_user(struct knote *kn, long hint);
129 static void filt_usertouch(struct knote *kn, struct kevent *kev,
131 static int filt_fsattach(struct knote *kn);
132 static void filt_fsdetach(struct knote *kn);
133 static int filt_fs(struct knote *kn, long hint);
135 static struct filterops file_filtops =
136 { FILTEROP_ISFD | FILTEROP_MPSAFE, filt_fileattach, NULL, NULL };
137 static struct filterops kqread_filtops =
138 { FILTEROP_ISFD | FILTEROP_MPSAFE, NULL, filt_kqdetach, filt_kqueue };
139 static struct filterops proc_filtops =
140 { FILTEROP_MPSAFE, filt_procattach, filt_procdetach, filt_proc };
141 static struct filterops timer_filtops =
142 { FILTEROP_MPSAFE, filt_timerattach, filt_timerdetach, filt_timer };
143 static struct filterops user_filtops =
144 { FILTEROP_MPSAFE, filt_userattach, filt_userdetach, filt_user };
145 static struct filterops fs_filtops =
146 { FILTEROP_MPSAFE, filt_fsattach, filt_fsdetach, filt_fs };
148 static int kq_ncallouts = 0;
149 static int kq_calloutmax = (4 * 1024);
150 SYSCTL_INT(_kern, OID_AUTO, kq_calloutmax, CTLFLAG_RW,
151 &kq_calloutmax, 0, "Maximum number of callouts allocated for kqueue");
152 static int kq_checkloop = 1000000;
153 SYSCTL_INT(_kern, OID_AUTO, kq_checkloop, CTLFLAG_RW,
154 &kq_checkloop, 0, "Maximum number of loops for kqueue scan");
155 static int kq_sleep_threshold = 20000;
156 SYSCTL_INT(_kern, OID_AUTO, kq_sleep_threshold, CTLFLAG_RW,
157 &kq_sleep_threshold, 0, "Minimum sleep duration without busy-looping");
159 #define KNOTE_ACTIVATE(kn) do { \
160 kn->kn_status |= KN_ACTIVE; \
161 if ((kn->kn_status & (KN_QUEUED | KN_DISABLED)) == 0) \
165 #define KN_HASHSIZE 64 /* XXX should be tunable */
166 #define KN_HASH(val, mask) (((val) ^ (val >> 8)) & (mask))
168 extern struct filterops aio_filtops;
169 extern struct filterops sig_filtops;
172 * Table for for all system-defined filters.
174 static struct filterops *sysfilt_ops[] = {
175 &file_filtops, /* EVFILT_READ */
176 &file_filtops, /* EVFILT_WRITE */
177 &aio_filtops, /* EVFILT_AIO */
178 &file_filtops, /* EVFILT_VNODE */
179 &proc_filtops, /* EVFILT_PROC */
180 &sig_filtops, /* EVFILT_SIGNAL */
181 &timer_filtops, /* EVFILT_TIMER */
182 &file_filtops, /* EVFILT_EXCEPT */
183 &user_filtops, /* EVFILT_USER */
184 &fs_filtops, /* EVFILT_FS */
187 static struct knote_cache_list knote_cache_lists[MAXCPU];
190 * Acquire a knote, return non-zero on success, 0 on failure.
192 * If we cannot acquire the knote we sleep and return 0. The knote
193 * may be stale on return in this case and the caller must restart
194 * whatever loop they are in.
196 * Related kq token must be held.
199 knote_acquire(struct knote *kn)
201 if (kn->kn_status & KN_PROCESSING) {
202 kn->kn_status |= KN_WAITING | KN_REPROCESS;
203 tsleep(kn, 0, "kqepts", hz);
204 /* knote may be stale now */
207 kn->kn_status |= KN_PROCESSING;
212 * Release an acquired knote, clearing KN_PROCESSING and handling any
213 * KN_REPROCESS events.
215 * Caller must be holding the related kq token
217 * Non-zero is returned if the knote is destroyed or detached.
220 knote_release(struct knote *kn)
224 while (kn->kn_status & KN_REPROCESS) {
225 kn->kn_status &= ~KN_REPROCESS;
226 if (kn->kn_status & KN_WAITING) {
227 kn->kn_status &= ~KN_WAITING;
230 if (kn->kn_status & KN_DELETING) {
231 knote_detach_and_drop(kn);
235 if (filter_event(kn, 0))
238 if (kn->kn_status & KN_DETACHED)
242 kn->kn_status &= ~KN_PROCESSING;
243 /* kn should not be accessed anymore */
248 filt_fileattach(struct knote *kn)
250 return (fo_kqfilter(kn->kn_fp, kn));
257 kqueue_kqfilter(struct file *fp, struct knote *kn)
259 struct kqueue *kq = (struct kqueue *)kn->kn_fp->f_data;
261 if (kn->kn_filter != EVFILT_READ)
264 kn->kn_fop = &kqread_filtops;
265 knote_insert(&kq->kq_kqinfo.ki_note, kn);
270 filt_kqdetach(struct knote *kn)
272 struct kqueue *kq = (struct kqueue *)kn->kn_fp->f_data;
274 knote_remove(&kq->kq_kqinfo.ki_note, kn);
279 filt_kqueue(struct knote *kn, long hint)
281 struct kqueue *kq = (struct kqueue *)kn->kn_fp->f_data;
283 kn->kn_data = kq->kq_count;
284 return (kn->kn_data > 0);
288 filt_procattach(struct knote *kn)
294 p = pfind(kn->kn_id);
295 if (p == NULL && (kn->kn_sfflags & NOTE_EXIT)) {
296 p = zpfind(kn->kn_id);
302 if (!PRISON_CHECK(curthread->td_ucred, p->p_ucred)) {
308 lwkt_gettoken(&p->p_token);
309 kn->kn_ptr.p_proc = p;
310 kn->kn_flags |= EV_CLEAR; /* automatically set */
313 * internal flag indicating registration done by kernel
315 if (kn->kn_flags & EV_FLAG1) {
316 kn->kn_data = kn->kn_sdata; /* ppid */
317 kn->kn_fflags = NOTE_CHILD;
318 kn->kn_flags &= ~EV_FLAG1;
321 knote_insert(&p->p_klist, kn);
324 * Immediately activate any exit notes if the target process is a
325 * zombie. This is necessary to handle the case where the target
326 * process, e.g. a child, dies before the kevent is negistered.
328 if (immediate && filt_proc(kn, NOTE_EXIT))
330 lwkt_reltoken(&p->p_token);
337 * The knote may be attached to a different process, which may exit,
338 * leaving nothing for the knote to be attached to. So when the process
339 * exits, the knote is marked as DETACHED and also flagged as ONESHOT so
340 * it will be deleted when read out. However, as part of the knote deletion,
341 * this routine is called, so a check is needed to avoid actually performing
342 * a detach, because the original process does not exist any more.
345 filt_procdetach(struct knote *kn)
349 if (kn->kn_status & KN_DETACHED)
351 p = kn->kn_ptr.p_proc;
352 knote_remove(&p->p_klist, kn);
356 filt_proc(struct knote *kn, long hint)
361 * mask off extra data
363 event = (u_int)hint & NOTE_PCTRLMASK;
366 * if the user is interested in this event, record it.
368 if (kn->kn_sfflags & event)
369 kn->kn_fflags |= event;
372 * Process is gone, so flag the event as finished. Detach the
373 * knote from the process now because the process will be poof,
376 if (event == NOTE_EXIT) {
377 struct proc *p = kn->kn_ptr.p_proc;
378 if ((kn->kn_status & KN_DETACHED) == 0) {
380 knote_remove(&p->p_klist, kn);
381 kn->kn_status |= KN_DETACHED;
382 kn->kn_data = p->p_xstat;
383 kn->kn_ptr.p_proc = NULL;
386 kn->kn_flags |= (EV_EOF | EV_NODATA | EV_ONESHOT);
391 * process forked, and user wants to track the new process,
392 * so attach a new knote to it, and immediately report an
393 * event with the parent's pid.
395 if ((event == NOTE_FORK) && (kn->kn_sfflags & NOTE_TRACK)) {
400 * register knote with new process.
402 kev.ident = hint & NOTE_PDATAMASK; /* pid */
403 kev.filter = kn->kn_filter;
404 kev.flags = kn->kn_flags | EV_ADD | EV_ENABLE | EV_FLAG1;
405 kev.fflags = kn->kn_sfflags;
406 kev.data = kn->kn_id; /* parent */
407 kev.udata = kn->kn_kevent.udata; /* preserve udata */
408 error = kqueue_register(kn->kn_kq, &kev);
410 kn->kn_fflags |= NOTE_TRACKERR;
413 return (kn->kn_fflags != 0);
417 filt_timerreset(struct knote *kn)
419 struct callout *calloutp;
423 tv.tv_sec = kn->kn_sdata / 1000;
424 tv.tv_usec = (kn->kn_sdata % 1000) * 1000;
425 tticks = tvtohz_high(&tv);
426 calloutp = (struct callout *)kn->kn_hook;
427 callout_reset(calloutp, tticks, filt_timerexpire, kn);
431 * The callout interlocks with callout_terminate() but can still
432 * race a deletion so if KN_DELETING is set we just don't touch
436 filt_timerexpire(void *knx)
438 struct knote *kn = knx;
439 struct kqueue *kq = kn->kn_kq;
441 lwkt_getpooltoken(kq);
444 * Open knote_acquire(), since we can't sleep in callout,
445 * however, we do need to record this expiration.
448 if (kn->kn_status & KN_PROCESSING) {
449 kn->kn_status |= KN_REPROCESS;
450 if ((kn->kn_status & KN_DELETING) == 0 &&
451 (kn->kn_flags & EV_ONESHOT) == 0)
453 lwkt_relpooltoken(kq);
456 KASSERT((kn->kn_status & KN_DELETING) == 0,
457 ("acquire a deleting knote %#x", kn->kn_status));
458 kn->kn_status |= KN_PROCESSING;
461 if ((kn->kn_flags & EV_ONESHOT) == 0)
466 lwkt_relpooltoken(kq);
470 * data contains amount of time to sleep, in milliseconds
473 filt_timerattach(struct knote *kn)
475 struct callout *calloutp;
478 prev_ncallouts = atomic_fetchadd_int(&kq_ncallouts, 1);
479 if (prev_ncallouts >= kq_calloutmax) {
480 atomic_subtract_int(&kq_ncallouts, 1);
485 kn->kn_flags |= EV_CLEAR; /* automatically set */
486 calloutp = kmalloc(sizeof(*calloutp), M_KQUEUE, M_WAITOK);
487 callout_init_mp(calloutp);
488 kn->kn_hook = (caddr_t)calloutp;
495 * This function is called with the knote flagged locked but it is
496 * still possible to race a callout event due to the callback blocking.
497 * We must call callout_terminate() instead of callout_stop() to deal
501 filt_timerdetach(struct knote *kn)
503 struct callout *calloutp;
505 calloutp = (struct callout *)kn->kn_hook;
506 callout_terminate(calloutp);
508 kfree(calloutp, M_KQUEUE);
509 atomic_subtract_int(&kq_ncallouts, 1);
513 filt_timer(struct knote *kn, long hint)
515 return (kn->kn_data != 0);
522 filt_userattach(struct knote *kn)
527 if (kn->kn_sfflags & NOTE_TRIGGER)
528 kn->kn_ptr.hookid = 1;
530 kn->kn_ptr.hookid = 0;
532 ffctrl = kn->kn_sfflags & NOTE_FFCTRLMASK;
533 kn->kn_sfflags &= NOTE_FFLAGSMASK;
539 kn->kn_fflags &= kn->kn_sfflags;
543 kn->kn_fflags |= kn->kn_sfflags;
547 kn->kn_fflags = kn->kn_sfflags;
551 /* XXX Return error? */
554 /* We just happen to copy this value as well. Undocumented. */
555 kn->kn_data = kn->kn_sdata;
561 filt_userdetach(struct knote *kn)
567 filt_user(struct knote *kn, long hint)
569 return (kn->kn_ptr.hookid);
573 filt_usertouch(struct knote *kn, struct kevent *kev, u_long type)
579 if (kev->fflags & NOTE_TRIGGER)
580 kn->kn_ptr.hookid = 1;
582 ffctrl = kev->fflags & NOTE_FFCTRLMASK;
583 kev->fflags &= NOTE_FFLAGSMASK;
589 kn->kn_fflags &= kev->fflags;
593 kn->kn_fflags |= kev->fflags;
597 kn->kn_fflags = kev->fflags;
601 /* XXX Return error? */
604 /* We just happen to copy this value as well. Undocumented. */
605 kn->kn_data = kev->data;
608 * This is not the correct use of EV_CLEAR in an event
609 * modification, it should have been passed as a NOTE instead.
610 * But we need to maintain compatibility with Apple & FreeBSD.
612 * Note however that EV_CLEAR can still be used when doing
613 * the initial registration of the event and works as expected
614 * (clears the event on reception).
616 if (kev->flags & EV_CLEAR) {
617 kn->kn_ptr.hookid = 0;
619 * Clearing kn->kn_data is fine, since it gets set
620 * every time anyway. We just shouldn't clear
621 * kn->kn_fflags here, since that would limit the
622 * possible uses of this API. NOTE_FFAND or
623 * NOTE_FFCOPY should be used for explicitly clearing
631 *kev = kn->kn_kevent;
632 kev->fflags = kn->kn_fflags;
633 kev->data = kn->kn_data;
634 if (kn->kn_flags & EV_CLEAR) {
635 kn->kn_ptr.hookid = 0;
636 /* kn_data, kn_fflags handled by parent */
641 panic("filt_usertouch() - invalid type (%ld)", type);
649 struct klist fs_klist = SLIST_HEAD_INITIALIZER(&fs_klist);
652 filt_fsattach(struct knote *kn)
654 kn->kn_flags |= EV_CLEAR;
655 knote_insert(&fs_klist, kn);
661 filt_fsdetach(struct knote *kn)
663 knote_remove(&fs_klist, kn);
667 filt_fs(struct knote *kn, long hint)
669 kn->kn_fflags |= hint;
670 return (kn->kn_fflags != 0);
674 * Initialize a kqueue.
676 * NOTE: The lwp/proc code initializes a kqueue for select/poll ops.
681 kqueue_init(struct kqueue *kq, struct filedesc *fdp)
683 TAILQ_INIT(&kq->kq_knpend);
684 TAILQ_INIT(&kq->kq_knlist);
687 SLIST_INIT(&kq->kq_kqinfo.ki_note);
691 * Terminate a kqueue. Freeing the actual kq itself is left up to the
692 * caller (it might be embedded in a lwp so we don't do it here).
694 * The kq's knlist must be completely eradicated so block on any
698 kqueue_terminate(struct kqueue *kq)
702 lwkt_getpooltoken(kq);
703 while ((kn = TAILQ_FIRST(&kq->kq_knlist)) != NULL) {
704 if (knote_acquire(kn))
705 knote_detach_and_drop(kn);
707 lwkt_relpooltoken(kq);
710 hashdestroy(kq->kq_knhash, M_KQUEUE, kq->kq_knhashmask);
711 kq->kq_knhash = NULL;
712 kq->kq_knhashmask = 0;
720 sys_kqueue(struct kqueue_args *uap)
722 struct thread *td = curthread;
727 error = falloc(td->td_lwp, &fp, &fd);
730 fp->f_flag = FREAD | FWRITE;
731 fp->f_type = DTYPE_KQUEUE;
732 fp->f_ops = &kqueueops;
734 kq = kmalloc(sizeof(struct kqueue), M_KQUEUE, M_WAITOK | M_ZERO);
735 kqueue_init(kq, td->td_proc->p_fd);
738 fsetfd(kq->kq_fdp, fp, fd);
739 uap->sysmsg_result = fd;
745 * Copy 'count' items into the destination list pointed to by uap->eventlist.
748 kevent_copyout(void *arg, struct kevent *kevp, int count, int *res)
750 struct kevent_copyin_args *kap;
753 kap = (struct kevent_copyin_args *)arg;
755 error = copyout(kevp, kap->ka->eventlist, count * sizeof(*kevp));
757 kap->ka->eventlist += count;
767 * Copy at most 'max' items from the list pointed to by kap->changelist,
768 * return number of items in 'events'.
771 kevent_copyin(void *arg, struct kevent *kevp, int max, int *events)
773 struct kevent_copyin_args *kap;
776 kap = (struct kevent_copyin_args *)arg;
778 count = min(kap->ka->nchanges - kap->pchanges, max);
779 error = copyin(kap->ka->changelist, kevp, count * sizeof *kevp);
781 kap->ka->changelist += count;
782 kap->pchanges += count;
793 kern_kevent(struct kqueue *kq, int nevents, int *res, void *uap,
794 k_copyin_fn kevent_copyinfn, k_copyout_fn kevent_copyoutfn,
795 struct timespec *tsp_in, int flags)
798 struct timespec *tsp, ats;
799 int i, n, total, error, nerrors = 0;
801 int limit = kq_checkloop;
802 struct kevent kev[KQ_NEVENTS];
804 struct lwkt_token *tok;
806 if (tsp_in == NULL || tsp_in->tv_sec || tsp_in->tv_nsec)
807 atomic_set_int(&curthread->td_mpflags, TDF_MP_BATCH_DEMARC);
814 error = kevent_copyinfn(uap, kev, KQ_NEVENTS, &n);
819 for (i = 0; i < n; i++) {
821 kevp->flags &= ~EV_SYSFLAGS;
822 error = kqueue_register(kq, kevp);
825 * If a registration returns an error we
826 * immediately post the error. The kevent()
827 * call itself will fail with the error if
828 * no space is available for posting.
830 * Such errors normally bypass the timeout/blocking
831 * code. However, if the copyoutfn function refuses
832 * to post the error (see sys_poll()), then we
835 if (error || (kevp->flags & EV_RECEIPT)) {
836 kevp->flags = EV_ERROR;
839 kevent_copyoutfn(uap, kevp, 1, res);
842 } else if (lres != *res) {
853 * Acquire/wait for events - setup timeout
856 if (tsp->tv_sec || tsp->tv_nsec) {
858 timespecadd(tsp, &ats); /* tsp = target time */
865 * Collect as many events as we can. Sleeping on successive
866 * loops is disabled if copyoutfn has incremented (*res).
868 * The loop stops if an error occurs, all events have been
869 * scanned (the marker has been reached), or fewer than the
870 * maximum number of events is found.
872 * The copyoutfn function does not have to increment (*res) in
873 * order for the loop to continue.
875 * NOTE: doselect() usually passes 0x7FFFFFFF for nevents.
879 marker.kn_filter = EVFILT_MARKER;
880 marker.kn_status = KN_PROCESSING;
881 tok = lwkt_token_pool_lookup(kq);
883 TAILQ_INSERT_TAIL(&kq->kq_knpend, &marker, kn_tqe);
885 while ((n = nevents - total) > 0) {
890 * If no events are pending sleep until timeout (if any)
891 * or an event occurs.
893 * After the sleep completes the marker is moved to the
894 * end of the list, making any received events available
897 if (kq->kq_count == 0 && *res == 0) {
898 int timeout, ustimeout = 0;
902 } else if (tsp->tv_sec == 0 && tsp->tv_nsec == 0) {
906 struct timespec atx = *tsp;
909 timespecsub(&atx, &ats);
910 if (atx.tv_sec < 0) {
914 timeout = atx.tv_sec > 24 * 60 * 60 ?
918 if (flags & KEVENT_TIMEOUT_PRECISE &&
920 if (atx.tv_sec == 0 &&
921 atx.tv_nsec < kq_sleep_threshold) {
922 DELAY(atx.tv_nsec / 1000);
925 } else if (atx.tv_sec < 2000) {
926 ustimeout = atx.tv_sec *
927 1000000 + atx.tv_nsec/1000;
929 ustimeout = 2000000000;
935 if (kq->kq_count == 0) {
937 if (__predict_false(kq->kq_sleep_cnt == 0)) {
939 * Guard against possible wrapping. And
940 * set it to 2, so that kqueue_wakeup()
941 * can wake everyone up.
943 kq->kq_sleep_cnt = 2;
945 if ((flags & KEVENT_TIMEOUT_PRECISE) &&
947 error = precise_sleep(kq, PCATCH,
948 "kqread", ustimeout);
950 error = tsleep(kq, PCATCH, "kqread",
954 /* don't restart after signals... */
955 if (error == ERESTART)
962 TAILQ_REMOVE(&kq->kq_knpend, &marker, kn_tqe);
963 TAILQ_INSERT_TAIL(&kq->kq_knpend, &marker,
970 * Process all received events
971 * Account for all non-spurious events in our total
973 i = kqueue_scan(kq, kev, n, &marker);
976 error = kevent_copyoutfn(uap, kev, i, res);
977 total += *res - lres;
981 if (limit && --limit == 0)
982 panic("kqueue: checkloop failed i=%d", i);
985 * Normally when fewer events are returned than requested
986 * we can stop. However, if only spurious events were
987 * collected the copyout will not bump (*res) and we have
994 * Deal with an edge case where spurious events can cause
995 * a loop to occur without moving the marker. This can
996 * prevent kqueue_scan() from picking up new events which
997 * race us. We must be sure to move the marker for this
1000 * NOTE: We do not want to move the marker if events
1001 * were scanned because normal kqueue operations
1002 * may reactivate events. Moving the marker in
1003 * that case could result in duplicates for the
1008 TAILQ_REMOVE(&kq->kq_knpend, &marker, kn_tqe);
1009 TAILQ_INSERT_TAIL(&kq->kq_knpend, &marker, kn_tqe);
1014 TAILQ_REMOVE(&kq->kq_knpend, &marker, kn_tqe);
1017 /* Timeouts do not return EWOULDBLOCK. */
1018 if (error == EWOULDBLOCK)
1027 sys_kevent(struct kevent_args *uap)
1029 struct thread *td = curthread;
1030 struct proc *p = td->td_proc;
1031 struct timespec ts, *tsp;
1033 struct file *fp = NULL;
1034 struct kevent_copyin_args *kap, ka;
1038 error = copyin(uap->timeout, &ts, sizeof(ts));
1045 fp = holdfp(p->p_fd, uap->fd, -1);
1048 if (fp->f_type != DTYPE_KQUEUE) {
1053 kq = (struct kqueue *)fp->f_data;
1059 error = kern_kevent(kq, uap->nevents, &uap->sysmsg_result, kap,
1060 kevent_copyin, kevent_copyout, tsp, 0);
1068 kqueue_register(struct kqueue *kq, struct kevent *kev)
1070 struct filedesc *fdp = kq->kq_fdp;
1071 struct klist *list = NULL;
1072 struct filterops *fops;
1073 struct file *fp = NULL;
1074 struct knote *kn = NULL;
1077 struct knote_cache_list *cache_list;
1079 if (kev->filter < 0) {
1080 if (kev->filter + EVFILT_SYSCOUNT < 0)
1082 fops = sysfilt_ops[~kev->filter]; /* to 0-base index */
1086 * filter attach routine is responsible for insuring that
1087 * the identifier can be attached to it.
1092 if (fops->f_flags & FILTEROP_ISFD) {
1093 /* validate descriptor */
1094 fp = holdfp(fdp, kev->ident, -1);
1099 cache_list = &knote_cache_lists[mycpuid];
1100 if (SLIST_EMPTY(&cache_list->knote_cache)) {
1101 struct knote *new_kn;
1103 new_kn = knote_alloc();
1105 SLIST_INSERT_HEAD(&cache_list->knote_cache, new_kn, kn_link);
1106 cache_list->knote_cache_cnt++;
1111 lwkt_getpooltoken(kq);
1114 * Make sure that only one thread can register event on this kqueue,
1115 * so that we would not suffer any race, even if the registration
1116 * blocked, i.e. kq token was released, and the kqueue was shared
1117 * between threads (this should be rare though).
1119 while (__predict_false(kq->kq_regtd != NULL && kq->kq_regtd != td)) {
1120 kq->kq_state |= KQ_REGWAIT;
1121 tsleep(&kq->kq_regtd, 0, "kqreg", 0);
1123 if (__predict_false(kq->kq_regtd != NULL)) {
1124 /* Recursive calling of kqueue_register() */
1127 /* Owner of the kq_regtd, i.e. td != NULL */
1132 list = &fp->f_klist;
1133 } else if (kq->kq_knhashmask) {
1134 list = &kq->kq_knhash[
1135 KN_HASH((u_long)kev->ident, kq->kq_knhashmask)];
1138 lwkt_getpooltoken(list);
1140 SLIST_FOREACH(kn, list, kn_link) {
1141 if (kn->kn_kq == kq &&
1142 kn->kn_filter == kev->filter &&
1143 kn->kn_id == kev->ident) {
1144 if (knote_acquire(kn) == 0)
1149 lwkt_relpooltoken(list);
1153 * NOTE: At this point if kn is non-NULL we will have acquired
1154 * it and set KN_PROCESSING.
1156 if (kn == NULL && ((kev->flags & EV_ADD) == 0)) {
1162 * kn now contains the matching knote, or NULL if no match
1164 if (kev->flags & EV_ADD) {
1167 kn = SLIST_FIRST(&cache_list->knote_cache);
1172 SLIST_REMOVE_HEAD(&cache_list->knote_cache,
1174 cache_list->knote_cache_cnt--;
1182 * apply reference count to knote structure, and
1183 * do not release it at the end of this routine.
1187 kn->kn_sfflags = kev->fflags;
1188 kn->kn_sdata = kev->data;
1191 kn->kn_kevent = *kev;
1194 * KN_PROCESSING prevents the knote from getting
1195 * ripped out from under us while we are trying
1196 * to attach it, in case the attach blocks.
1198 kn->kn_status = KN_PROCESSING;
1200 if ((error = filter_attach(kn)) != 0) {
1201 kn->kn_status |= KN_DELETING | KN_REPROCESS;
1207 * Interlock against close races which either tried
1208 * to remove our knote while we were blocked or missed
1209 * it entirely prior to our attachment. We do not
1210 * want to end up with a knote on a closed descriptor.
1212 if ((fops->f_flags & FILTEROP_ISFD) &&
1213 checkfdclosed(fdp, kev->ident, kn->kn_fp)) {
1214 kn->kn_status |= KN_DELETING | KN_REPROCESS;
1218 * The user may change some filter values after the
1219 * initial EV_ADD, but doing so will not reset any
1220 * filter which have already been triggered.
1222 KKASSERT(kn->kn_status & KN_PROCESSING);
1223 if (fops == &user_filtops) {
1224 filt_usertouch(kn, kev, EVENT_REGISTER);
1226 kn->kn_sfflags = kev->fflags;
1227 kn->kn_sdata = kev->data;
1228 kn->kn_kevent.udata = kev->udata;
1233 * Execute the filter event to immediately activate the
1234 * knote if necessary. If reprocessing events are pending
1235 * due to blocking above we do not run the filter here
1236 * but instead let knote_release() do it. Otherwise we
1237 * might run the filter on a deleted event.
1239 if ((kn->kn_status & KN_REPROCESS) == 0) {
1240 if (filter_event(kn, 0))
1243 } else if (kev->flags & EV_DELETE) {
1245 * Delete the existing knote
1247 knote_detach_and_drop(kn);
1251 * Modify an existing event.
1253 * The user may change some filter values after the
1254 * initial EV_ADD, but doing so will not reset any
1255 * filter which have already been triggered.
1257 KKASSERT(kn->kn_status & KN_PROCESSING);
1258 if (fops == &user_filtops) {
1259 filt_usertouch(kn, kev, EVENT_REGISTER);
1261 kn->kn_sfflags = kev->fflags;
1262 kn->kn_sdata = kev->data;
1263 kn->kn_kevent.udata = kev->udata;
1267 * Execute the filter event to immediately activate the
1268 * knote if necessary. If reprocessing events are pending
1269 * due to blocking above we do not run the filter here
1270 * but instead let knote_release() do it. Otherwise we
1271 * might run the filter on a deleted event.
1273 if ((kn->kn_status & KN_REPROCESS) == 0) {
1274 if (filter_event(kn, 0))
1280 * Disablement does not deactivate a knote here.
1282 if ((kev->flags & EV_DISABLE) &&
1283 ((kn->kn_status & KN_DISABLED) == 0)) {
1284 kn->kn_status |= KN_DISABLED;
1288 * Re-enablement may have to immediately enqueue an active knote.
1290 if ((kev->flags & EV_ENABLE) && (kn->kn_status & KN_DISABLED)) {
1291 kn->kn_status &= ~KN_DISABLED;
1292 if ((kn->kn_status & KN_ACTIVE) &&
1293 ((kn->kn_status & KN_QUEUED) == 0)) {
1299 * Handle any required reprocessing
1302 /* kn may be invalid now */
1305 if (td != NULL) { /* Owner of the kq_regtd */
1306 kq->kq_regtd = NULL;
1307 if (__predict_false(kq->kq_state & KQ_REGWAIT)) {
1308 kq->kq_state &= ~KQ_REGWAIT;
1309 wakeup(&kq->kq_regtd);
1312 lwkt_relpooltoken(kq);
1319 * Scan the kqueue, return the number of active events placed in kevp up
1322 * Continuous mode events may get recycled, do not continue scanning past
1323 * marker unless no events have been collected.
1326 kqueue_scan(struct kqueue *kq, struct kevent *kevp, int count,
1327 struct knote *marker)
1329 struct knote *kn, local_marker;
1333 local_marker.kn_filter = EVFILT_MARKER;
1334 local_marker.kn_status = KN_PROCESSING;
1336 lwkt_getpooltoken(kq);
1341 TAILQ_INSERT_HEAD(&kq->kq_knpend, &local_marker, kn_tqe);
1343 kn = TAILQ_NEXT(&local_marker, kn_tqe);
1344 if (kn->kn_filter == EVFILT_MARKER) {
1345 /* Marker reached, we are done */
1349 /* Move local marker past some other threads marker */
1350 kn = TAILQ_NEXT(kn, kn_tqe);
1351 TAILQ_REMOVE(&kq->kq_knpend, &local_marker, kn_tqe);
1352 TAILQ_INSERT_BEFORE(kn, &local_marker, kn_tqe);
1357 * We can't skip a knote undergoing processing, otherwise
1358 * we risk not returning it when the user process expects
1359 * it should be returned. Sleep and retry.
1361 if (knote_acquire(kn) == 0)
1365 * Remove the event for processing.
1367 * WARNING! We must leave KN_QUEUED set to prevent the
1368 * event from being KNOTE_ACTIVATE()d while
1369 * the queue state is in limbo, in case we
1372 TAILQ_REMOVE(&kq->kq_knpend, kn, kn_tqe);
1376 * We have to deal with an extremely important race against
1377 * file descriptor close()s here. The file descriptor can
1378 * disappear MPSAFE, and there is a small window of
1379 * opportunity between that and the call to knote_fdclose().
1381 * If we hit that window here while doselect or dopoll is
1382 * trying to delete a spurious event they will not be able
1383 * to match up the event against a knote and will go haywire.
1385 if ((kn->kn_fop->f_flags & FILTEROP_ISFD) &&
1386 checkfdclosed(kq->kq_fdp, kn->kn_kevent.ident, kn->kn_fp)) {
1387 kn->kn_status |= KN_DELETING | KN_REPROCESS;
1390 if (kn->kn_status & KN_DISABLED) {
1392 * If disabled we ensure the event is not queued
1393 * but leave its active bit set. On re-enablement
1394 * the event may be immediately triggered.
1396 kn->kn_status &= ~KN_QUEUED;
1397 } else if ((kn->kn_flags & EV_ONESHOT) == 0 &&
1398 (kn->kn_status & KN_DELETING) == 0 &&
1399 filter_event(kn, 0) == 0) {
1401 * If not running in one-shot mode and the event
1402 * is no longer present we ensure it is removed
1403 * from the queue and ignore it.
1405 kn->kn_status &= ~(KN_QUEUED | KN_ACTIVE);
1410 if (kn->kn_fop == &user_filtops)
1411 filt_usertouch(kn, kevp, EVENT_PROCESS);
1413 *kevp = kn->kn_kevent;
1418 if (kn->kn_flags & EV_ONESHOT) {
1419 kn->kn_status &= ~KN_QUEUED;
1420 kn->kn_status |= KN_DELETING | KN_REPROCESS;
1422 if (kn->kn_flags & (EV_CLEAR | EV_DISPATCH)) {
1423 if (kn->kn_flags & EV_CLEAR) {
1427 if (kn->kn_flags & EV_DISPATCH) {
1428 kn->kn_status |= KN_DISABLED;
1430 kn->kn_status &= ~(KN_QUEUED |
1433 TAILQ_INSERT_TAIL(&kq->kq_knpend, kn, kn_tqe);
1440 * Handle any post-processing states
1444 TAILQ_REMOVE(&kq->kq_knpend, &local_marker, kn_tqe);
1446 lwkt_relpooltoken(kq);
1452 * This could be expanded to call kqueue_scan, if desired.
1457 kqueue_read(struct file *fp, struct uio *uio, struct ucred *cred, int flags)
1466 kqueue_write(struct file *fp, struct uio *uio, struct ucred *cred, int flags)
1475 kqueue_ioctl(struct file *fp, u_long com, caddr_t data,
1476 struct ucred *cred, struct sysmsg *msg)
1481 kq = (struct kqueue *)fp->f_data;
1482 lwkt_getpooltoken(kq);
1486 kq->kq_state |= KQ_ASYNC;
1488 kq->kq_state &= ~KQ_ASYNC;
1492 error = fsetown(*(int *)data, &kq->kq_sigio);
1498 lwkt_relpooltoken(kq);
1506 kqueue_stat(struct file *fp, struct stat *st, struct ucred *cred)
1508 struct kqueue *kq = (struct kqueue *)fp->f_data;
1510 bzero((void *)st, sizeof(*st));
1511 st->st_size = kq->kq_count;
1512 st->st_blksize = sizeof(struct kevent);
1513 st->st_mode = S_IFIFO;
1521 kqueue_close(struct file *fp)
1523 struct kqueue *kq = (struct kqueue *)fp->f_data;
1525 kqueue_terminate(kq);
1528 funsetown(&kq->kq_sigio);
1530 kfree(kq, M_KQUEUE);
1535 kqueue_wakeup(struct kqueue *kq)
1537 if (kq->kq_sleep_cnt) {
1538 u_int sleep_cnt = kq->kq_sleep_cnt;
1540 kq->kq_sleep_cnt = 0;
1546 KNOTE(&kq->kq_kqinfo.ki_note, 0);
1550 * Calls filterops f_attach function, acquiring mplock if filter is not
1551 * marked as FILTEROP_MPSAFE.
1553 * Caller must be holding the related kq token
1556 filter_attach(struct knote *kn)
1560 if (kn->kn_fop->f_flags & FILTEROP_MPSAFE) {
1561 ret = kn->kn_fop->f_attach(kn);
1564 ret = kn->kn_fop->f_attach(kn);
1571 * Detach the knote and drop it, destroying the knote.
1573 * Calls filterops f_detach function, acquiring mplock if filter is not
1574 * marked as FILTEROP_MPSAFE.
1576 * Caller must be holding the related kq token
1579 knote_detach_and_drop(struct knote *kn)
1581 kn->kn_status |= KN_DELETING | KN_REPROCESS;
1582 if (kn->kn_fop->f_flags & FILTEROP_MPSAFE) {
1583 kn->kn_fop->f_detach(kn);
1586 kn->kn_fop->f_detach(kn);
1593 * Calls filterops f_event function, acquiring mplock if filter is not
1594 * marked as FILTEROP_MPSAFE.
1596 * If the knote is in the middle of being created or deleted we cannot
1597 * safely call the filter op.
1599 * Caller must be holding the related kq token
1602 filter_event(struct knote *kn, long hint)
1606 if (kn->kn_fop->f_flags & FILTEROP_MPSAFE) {
1607 ret = kn->kn_fop->f_event(kn, hint);
1610 ret = kn->kn_fop->f_event(kn, hint);
1617 * Walk down a list of knotes, activating them if their event has triggered.
1619 * If we encounter any knotes which are undergoing processing we just mark
1620 * them for reprocessing and do not try to [re]activate the knote. However,
1621 * if a hint is being passed we have to wait and that makes things a bit
1625 knote(struct klist *list, long hint)
1629 struct knote *kntmp;
1631 lwkt_getpooltoken(list);
1633 SLIST_FOREACH(kn, list, kn_next) {
1635 lwkt_getpooltoken(kq);
1637 /* temporary verification hack */
1638 SLIST_FOREACH(kntmp, list, kn_next) {
1642 if (kn != kntmp || kn->kn_kq != kq) {
1643 lwkt_relpooltoken(kq);
1647 if (kn->kn_status & KN_PROCESSING) {
1649 * Someone else is processing the knote, ask the
1650 * other thread to reprocess it and don't mess
1651 * with it otherwise.
1654 kn->kn_status |= KN_REPROCESS;
1655 lwkt_relpooltoken(kq);
1660 * If the hint is non-zero we have to wait or risk
1661 * losing the state the caller is trying to update.
1663 * XXX This is a real problem, certain process
1664 * and signal filters will bump kn_data for
1665 * already-processed notes more than once if
1666 * we restart the list scan. FIXME.
1668 kn->kn_status |= KN_WAITING | KN_REPROCESS;
1669 tsleep(kn, 0, "knotec", hz);
1670 lwkt_relpooltoken(kq);
1675 * Become the reprocessing master ourselves.
1677 * If hint is non-zero running the event is mandatory
1678 * when not deleting so do it whether reprocessing is
1681 kn->kn_status |= KN_PROCESSING;
1682 if ((kn->kn_status & KN_DELETING) == 0) {
1683 if (filter_event(kn, hint))
1686 if (knote_release(kn)) {
1687 lwkt_relpooltoken(kq);
1690 lwkt_relpooltoken(kq);
1692 lwkt_relpooltoken(list);
1696 * Insert knote at head of klist.
1698 * This function may only be called via a filter function and thus
1699 * kq_token should already be held and marked for processing.
1702 knote_insert(struct klist *klist, struct knote *kn)
1704 lwkt_getpooltoken(klist);
1705 KKASSERT(kn->kn_status & KN_PROCESSING);
1706 SLIST_INSERT_HEAD(klist, kn, kn_next);
1707 lwkt_relpooltoken(klist);
1711 * Remove knote from a klist
1713 * This function may only be called via a filter function and thus
1714 * kq_token should already be held and marked for processing.
1717 knote_remove(struct klist *klist, struct knote *kn)
1719 lwkt_getpooltoken(klist);
1720 KKASSERT(kn->kn_status & KN_PROCESSING);
1721 SLIST_REMOVE(klist, kn, knote, kn_next);
1722 lwkt_relpooltoken(klist);
1726 knote_assume_knotes(struct kqinfo *src, struct kqinfo *dst,
1727 struct filterops *ops, void *hook)
1732 lwkt_getpooltoken(&src->ki_note);
1733 lwkt_getpooltoken(&dst->ki_note);
1734 while ((kn = SLIST_FIRST(&src->ki_note)) != NULL) {
1736 lwkt_getpooltoken(kq);
1737 if (SLIST_FIRST(&src->ki_note) != kn || kn->kn_kq != kq) {
1738 lwkt_relpooltoken(kq);
1741 if (knote_acquire(kn)) {
1742 knote_remove(&src->ki_note, kn);
1745 knote_insert(&dst->ki_note, kn);
1747 /* kn may be invalid now */
1749 lwkt_relpooltoken(kq);
1751 lwkt_relpooltoken(&dst->ki_note);
1752 lwkt_relpooltoken(&src->ki_note);
1756 * Remove all knotes referencing a specified fd
1759 knote_fdclose(struct file *fp, struct filedesc *fdp, int fd)
1763 struct knote *kntmp;
1765 lwkt_getpooltoken(&fp->f_klist);
1767 SLIST_FOREACH(kn, &fp->f_klist, kn_link) {
1768 if (kn->kn_kq->kq_fdp == fdp && kn->kn_id == fd) {
1770 lwkt_getpooltoken(kq);
1772 /* temporary verification hack */
1773 SLIST_FOREACH(kntmp, &fp->f_klist, kn_link) {
1777 if (kn != kntmp || kn->kn_kq->kq_fdp != fdp ||
1778 kn->kn_id != fd || kn->kn_kq != kq) {
1779 lwkt_relpooltoken(kq);
1782 if (knote_acquire(kn))
1783 knote_detach_and_drop(kn);
1784 lwkt_relpooltoken(kq);
1788 lwkt_relpooltoken(&fp->f_klist);
1792 * Low level attach function.
1794 * The knote should already be marked for processing.
1795 * Caller must hold the related kq token.
1798 knote_attach(struct knote *kn)
1801 struct kqueue *kq = kn->kn_kq;
1803 if (kn->kn_fop->f_flags & FILTEROP_ISFD) {
1804 KKASSERT(kn->kn_fp);
1805 list = &kn->kn_fp->f_klist;
1807 if (kq->kq_knhashmask == 0)
1808 kq->kq_knhash = hashinit(KN_HASHSIZE, M_KQUEUE,
1809 &kq->kq_knhashmask);
1810 list = &kq->kq_knhash[KN_HASH(kn->kn_id, kq->kq_knhashmask)];
1812 lwkt_getpooltoken(list);
1813 SLIST_INSERT_HEAD(list, kn, kn_link);
1814 lwkt_relpooltoken(list);
1815 TAILQ_INSERT_HEAD(&kq->kq_knlist, kn, kn_kqlink);
1819 * Low level drop function.
1821 * The knote should already be marked for processing.
1822 * Caller must hold the related kq token.
1825 knote_drop(struct knote *kn)
1832 if (kn->kn_fop->f_flags & FILTEROP_ISFD)
1833 list = &kn->kn_fp->f_klist;
1835 list = &kq->kq_knhash[KN_HASH(kn->kn_id, kq->kq_knhashmask)];
1837 lwkt_getpooltoken(list);
1838 SLIST_REMOVE(list, kn, knote, kn_link);
1839 lwkt_relpooltoken(list);
1840 TAILQ_REMOVE(&kq->kq_knlist, kn, kn_kqlink);
1841 if (kn->kn_status & KN_QUEUED)
1843 if (kn->kn_fop->f_flags & FILTEROP_ISFD) {
1851 * Low level enqueue function.
1853 * The knote should already be marked for processing.
1854 * Caller must be holding the kq token
1857 knote_enqueue(struct knote *kn)
1859 struct kqueue *kq = kn->kn_kq;
1861 KASSERT((kn->kn_status & KN_QUEUED) == 0, ("knote already queued"));
1862 TAILQ_INSERT_TAIL(&kq->kq_knpend, kn, kn_tqe);
1863 kn->kn_status |= KN_QUEUED;
1867 * Send SIGIO on request (typically set up as a mailbox signal)
1869 if (kq->kq_sigio && (kq->kq_state & KQ_ASYNC) && kq->kq_count == 1)
1870 pgsigio(kq->kq_sigio, SIGIO, 0);
1876 * Low level dequeue function.
1878 * The knote should already be marked for processing.
1879 * Caller must be holding the kq token
1882 knote_dequeue(struct knote *kn)
1884 struct kqueue *kq = kn->kn_kq;
1886 KASSERT(kn->kn_status & KN_QUEUED, ("knote not queued"));
1887 TAILQ_REMOVE(&kq->kq_knpend, kn, kn_tqe);
1888 kn->kn_status &= ~KN_QUEUED;
1892 static struct knote *
1895 return kmalloc(sizeof(struct knote), M_KQUEUE, M_WAITOK);
1899 knote_free(struct knote *kn)
1901 struct knote_cache_list *cache_list;
1903 cache_list = &knote_cache_lists[mycpuid];
1904 if (cache_list->knote_cache_cnt < KNOTE_CACHE_MAX) {
1906 SLIST_INSERT_HEAD(&cache_list->knote_cache, kn, kn_link);
1907 cache_list->knote_cache_cnt++;
1911 kfree(kn, M_KQUEUE);
1920 precise_sleep_intr(systimer_t info, int in_ipi, struct intrframe *frame)
1922 struct sleepinfo *si;
1930 precise_sleep(void *ident, int flags, const char *wmesg, int us)
1932 struct systimer info;
1933 struct sleepinfo si = {
1939 tsleep_interlock(ident, flags);
1940 systimer_init_oneshot(&info, precise_sleep_intr, &si,
1942 r = tsleep(ident, flags | PINTERLOCKED, wmesg, 0);
1943 systimer_del(&info);