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 1.2.2.9 2003/05/08 07:47:16 kbyanc 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>
36 #include <sys/fcntl.h>
37 #include <sys/select.h>
38 #include <sys/queue.h>
39 #include <sys/event.h>
40 #include <sys/eventvar.h>
42 #include <sys/protosw.h>
43 #include <sys/socket.h>
44 #include <sys/socketvar.h>
46 #include <sys/sysctl.h>
47 #include <sys/sysproto.h>
50 #include <vm/vm_zone.h>
52 MALLOC_DEFINE(M_KQUEUE, "kqueue", "memory for kqueue system");
54 static int kqueue_scan(struct file *fp, int maxevents,
55 struct kevent *ulistp, const struct timespec *timeout,
57 static int kqueue_read(struct file *fp, struct uio *uio,
58 struct ucred *cred, int flags, struct proc *p);
59 static int kqueue_write(struct file *fp, struct uio *uio,
60 struct ucred *cred, int flags, struct proc *p);
61 static int kqueue_ioctl(struct file *fp, u_long com, caddr_t data,
63 static int kqueue_poll(struct file *fp, int events, struct ucred *cred,
65 static int kqueue_kqfilter(struct file *fp, struct knote *kn);
66 static int kqueue_stat(struct file *fp, struct stat *st, struct proc *p);
67 static int kqueue_close(struct file *fp, struct proc *p);
68 static void kqueue_wakeup(struct kqueue *kq);
70 static struct fileops kqueueops = {
80 static void knote_attach(struct knote *kn, struct filedesc *fdp);
81 static void knote_drop(struct knote *kn, struct proc *p);
82 static void knote_enqueue(struct knote *kn);
83 static void knote_dequeue(struct knote *kn);
84 static void knote_init(void);
85 static struct knote *knote_alloc(void);
86 static void knote_free(struct knote *kn);
88 static void filt_kqdetach(struct knote *kn);
89 static int filt_kqueue(struct knote *kn, long hint);
90 static int filt_procattach(struct knote *kn);
91 static void filt_procdetach(struct knote *kn);
92 static int filt_proc(struct knote *kn, long hint);
93 static int filt_fileattach(struct knote *kn);
94 static void filt_timerexpire(void *knx);
95 static int filt_timerattach(struct knote *kn);
96 static void filt_timerdetach(struct knote *kn);
97 static int filt_timer(struct knote *kn, long hint);
99 static struct filterops file_filtops =
100 { 1, filt_fileattach, NULL, NULL };
101 static struct filterops kqread_filtops =
102 { 1, NULL, filt_kqdetach, filt_kqueue };
103 static struct filterops proc_filtops =
104 { 0, filt_procattach, filt_procdetach, filt_proc };
105 static struct filterops timer_filtops =
106 { 0, filt_timerattach, filt_timerdetach, filt_timer };
108 static vm_zone_t knote_zone;
109 static int kq_ncallouts = 0;
110 static int kq_calloutmax = (4 * 1024);
111 SYSCTL_INT(_kern, OID_AUTO, kq_calloutmax, CTLFLAG_RW,
112 &kq_calloutmax, 0, "Maximum number of callouts allocated for kqueue");
114 #define KNOTE_ACTIVATE(kn) do { \
115 kn->kn_status |= KN_ACTIVE; \
116 if ((kn->kn_status & (KN_QUEUED | KN_DISABLED)) == 0) \
120 #define KN_HASHSIZE 64 /* XXX should be tunable */
121 #define KN_HASH(val, mask) (((val) ^ (val >> 8)) & (mask))
123 extern struct filterops aio_filtops;
124 extern struct filterops sig_filtops;
127 * Table for for all system-defined filters.
129 static struct filterops *sysfilt_ops[] = {
130 &file_filtops, /* EVFILT_READ */
131 &file_filtops, /* EVFILT_WRITE */
132 &aio_filtops, /* EVFILT_AIO */
133 &file_filtops, /* EVFILT_VNODE */
134 &proc_filtops, /* EVFILT_PROC */
135 &sig_filtops, /* EVFILT_SIGNAL */
136 &timer_filtops, /* EVFILT_TIMER */
140 filt_fileattach(struct knote *kn)
143 return (fo_kqfilter(kn->kn_fp, kn));
148 kqueue_kqfilter(struct file *fp, struct knote *kn)
150 struct kqueue *kq = (struct kqueue *)kn->kn_fp->f_data;
152 if (kn->kn_filter != EVFILT_READ)
155 kn->kn_fop = &kqread_filtops;
156 SLIST_INSERT_HEAD(&kq->kq_sel.si_note, kn, kn_selnext);
161 filt_kqdetach(struct knote *kn)
163 struct kqueue *kq = (struct kqueue *)kn->kn_fp->f_data;
165 SLIST_REMOVE(&kq->kq_sel.si_note, kn, knote, kn_selnext);
170 filt_kqueue(struct knote *kn, long hint)
172 struct kqueue *kq = (struct kqueue *)kn->kn_fp->f_data;
174 kn->kn_data = kq->kq_count;
175 return (kn->kn_data > 0);
179 filt_procattach(struct knote *kn)
185 p = pfind(kn->kn_id);
186 if (p == NULL && (kn->kn_sfflags & NOTE_EXIT)) {
187 p = zpfind(kn->kn_id);
192 if (! PRISON_CHECK(curproc, p))
195 kn->kn_ptr.p_proc = p;
196 kn->kn_flags |= EV_CLEAR; /* automatically set */
199 * internal flag indicating registration done by kernel
201 if (kn->kn_flags & EV_FLAG1) {
202 kn->kn_data = kn->kn_sdata; /* ppid */
203 kn->kn_fflags = NOTE_CHILD;
204 kn->kn_flags &= ~EV_FLAG1;
207 /* XXX lock the proc here while adding to the list? */
208 SLIST_INSERT_HEAD(&p->p_klist, kn, kn_selnext);
211 * Immediately activate any exit notes if the target process is a
212 * zombie. This is necessary to handle the case where the target
213 * process, e.g. a child, dies before the kevent is registered.
215 if (immediate && filt_proc(kn, NOTE_EXIT))
222 * The knote may be attached to a different process, which may exit,
223 * leaving nothing for the knote to be attached to. So when the process
224 * exits, the knote is marked as DETACHED and also flagged as ONESHOT so
225 * it will be deleted when read out. However, as part of the knote deletion,
226 * this routine is called, so a check is needed to avoid actually performing
227 * a detach, because the original process does not exist any more.
230 filt_procdetach(struct knote *kn)
232 struct proc *p = kn->kn_ptr.p_proc;
234 if (kn->kn_status & KN_DETACHED)
237 /* XXX locking? this might modify another process. */
238 SLIST_REMOVE(&p->p_klist, kn, knote, kn_selnext);
242 filt_proc(struct knote *kn, long hint)
247 * mask off extra data
249 event = (u_int)hint & NOTE_PCTRLMASK;
252 * if the user is interested in this event, record it.
254 if (kn->kn_sfflags & event)
255 kn->kn_fflags |= event;
258 * process is gone, so flag the event as finished.
260 if (event == NOTE_EXIT) {
261 kn->kn_status |= KN_DETACHED;
262 kn->kn_flags |= (EV_EOF | EV_ONESHOT);
267 * process forked, and user wants to track the new process,
268 * so attach a new knote to it, and immediately report an
269 * event with the parent's pid.
271 if ((event == NOTE_FORK) && (kn->kn_sfflags & NOTE_TRACK)) {
276 * register knote with new process.
278 kev.ident = hint & NOTE_PDATAMASK; /* pid */
279 kev.filter = kn->kn_filter;
280 kev.flags = kn->kn_flags | EV_ADD | EV_ENABLE | EV_FLAG1;
281 kev.fflags = kn->kn_sfflags;
282 kev.data = kn->kn_id; /* parent */
283 kev.udata = kn->kn_kevent.udata; /* preserve udata */
284 error = kqueue_register(kn->kn_kq, &kev, NULL);
286 kn->kn_fflags |= NOTE_TRACKERR;
289 return (kn->kn_fflags != 0);
293 filt_timerexpire(void *knx)
295 struct knote *kn = knx;
296 struct callout *calloutp;
303 if ((kn->kn_flags & EV_ONESHOT) == 0) {
304 tv.tv_sec = kn->kn_sdata / 1000;
305 tv.tv_usec = (kn->kn_sdata % 1000) * 1000;
306 tticks = tvtohz(&tv);
307 calloutp = (struct callout *)kn->kn_hook;
308 callout_reset(calloutp, tticks, filt_timerexpire, kn);
313 * data contains amount of time to sleep, in milliseconds
316 filt_timerattach(struct knote *kn)
318 struct callout *calloutp;
322 if (kq_ncallouts >= kq_calloutmax)
326 tv.tv_sec = kn->kn_sdata / 1000;
327 tv.tv_usec = (kn->kn_sdata % 1000) * 1000;
328 tticks = tvtohz(&tv);
330 kn->kn_flags |= EV_CLEAR; /* automatically set */
331 MALLOC(calloutp, struct callout *, sizeof(*calloutp),
333 callout_init(calloutp);
334 callout_reset(calloutp, tticks, filt_timerexpire, kn);
335 kn->kn_hook = (caddr_t)calloutp;
341 filt_timerdetach(struct knote *kn)
343 struct callout *calloutp;
345 calloutp = (struct callout *)kn->kn_hook;
346 callout_stop(calloutp);
347 FREE(calloutp, M_KQUEUE);
352 filt_timer(struct knote *kn, long hint)
355 return (kn->kn_data != 0);
359 kqueue(struct proc *p, struct kqueue_args *uap)
361 struct filedesc *fdp = p->p_fd;
366 error = falloc(p, &fp, &fd);
369 fp->f_flag = FREAD | FWRITE;
370 fp->f_type = DTYPE_KQUEUE;
371 fp->f_ops = &kqueueops;
372 kq = malloc(sizeof(struct kqueue), M_KQUEUE, M_WAITOK | M_ZERO);
373 TAILQ_INIT(&kq->kq_head);
374 fp->f_data = (caddr_t)kq;
376 if (fdp->fd_knlistsize < 0)
377 fdp->fd_knlistsize = 0; /* this process has a kq */
382 #ifndef _SYS_SYSPROTO_H_
385 const struct kevent *changelist;
387 struct kevent *eventlist;
389 const struct timespec *timeout;
393 kevent(struct proc *p, struct kevent_args *uap)
395 struct filedesc* fdp = p->p_fd;
398 struct file *fp = NULL;
400 int i, n, nerrors, error;
402 if (((u_int)uap->fd) >= fdp->fd_nfiles ||
403 (fp = fdp->fd_ofiles[uap->fd]) == NULL ||
404 (fp->f_type != DTYPE_KQUEUE))
409 if (uap->timeout != NULL) {
410 error = copyin(uap->timeout, &ts, sizeof(ts));
416 kq = (struct kqueue *)fp->f_data;
419 while (uap->nchanges > 0) {
420 n = uap->nchanges > KQ_NEVENTS ? KQ_NEVENTS : uap->nchanges;
421 error = copyin(uap->changelist, kq->kq_kev,
422 n * sizeof(struct kevent));
425 for (i = 0; i < n; i++) {
426 kevp = &kq->kq_kev[i];
427 kevp->flags &= ~EV_SYSFLAGS;
428 error = kqueue_register(kq, kevp, p);
430 if (uap->nevents != 0) {
431 kevp->flags = EV_ERROR;
433 (void) copyout((caddr_t)kevp,
434 (caddr_t)uap->eventlist,
445 uap->changelist += n;
448 p->p_retval[0] = nerrors;
453 error = kqueue_scan(fp, uap->nevents, uap->eventlist, uap->timeout, p);
461 kqueue_register(struct kqueue *kq, struct kevent *kev, struct proc *p)
463 struct filedesc *fdp = kq->kq_fdp;
464 struct filterops *fops;
465 struct file *fp = NULL;
466 struct knote *kn = NULL;
469 if (kev->filter < 0) {
470 if (kev->filter + EVFILT_SYSCOUNT < 0)
472 fops = sysfilt_ops[~kev->filter]; /* to 0-base index */
476 * filter attach routine is responsible for insuring that
477 * the identifier can be attached to it.
479 printf("unknown filter: %d\n", kev->filter);
484 /* validate descriptor */
485 if ((u_int)kev->ident >= fdp->fd_nfiles ||
486 (fp = fdp->fd_ofiles[kev->ident]) == NULL)
490 if (kev->ident < fdp->fd_knlistsize) {
491 SLIST_FOREACH(kn, &fdp->fd_knlist[kev->ident], kn_link)
492 if (kq == kn->kn_kq &&
493 kev->filter == kn->kn_filter)
497 if (fdp->fd_knhashmask != 0) {
500 list = &fdp->fd_knhash[
501 KN_HASH((u_long)kev->ident, fdp->fd_knhashmask)];
502 SLIST_FOREACH(kn, list, kn_link)
503 if (kev->ident == kn->kn_id &&
505 kev->filter == kn->kn_filter)
510 if (kn == NULL && ((kev->flags & EV_ADD) == 0)) {
516 * kn now contains the matching knote, or NULL if no match
518 if (kev->flags & EV_ADD) {
531 * apply reference count to knote structure, and
532 * do not release it at the end of this routine.
536 kn->kn_sfflags = kev->fflags;
537 kn->kn_sdata = kev->data;
540 kn->kn_kevent = *kev;
542 knote_attach(kn, fdp);
543 if ((error = fops->f_attach(kn)) != 0) {
549 * The user may change some filter values after the
550 * initial EV_ADD, but doing so will not reset any
551 * filter which have already been triggered.
553 kn->kn_sfflags = kev->fflags;
554 kn->kn_sdata = kev->data;
555 kn->kn_kevent.udata = kev->udata;
559 if (kn->kn_fop->f_event(kn, 0))
563 } else if (kev->flags & EV_DELETE) {
564 kn->kn_fop->f_detach(kn);
569 if ((kev->flags & EV_DISABLE) &&
570 ((kn->kn_status & KN_DISABLED) == 0)) {
572 kn->kn_status |= KN_DISABLED;
576 if ((kev->flags & EV_ENABLE) && (kn->kn_status & KN_DISABLED)) {
578 kn->kn_status &= ~KN_DISABLED;
579 if ((kn->kn_status & KN_ACTIVE) &&
580 ((kn->kn_status & KN_QUEUED) == 0))
592 kqueue_scan(struct file *fp, int maxevents, struct kevent *ulistp,
593 const struct timespec *tsp, struct proc *p)
595 struct kqueue *kq = (struct kqueue *)fp->f_data;
597 struct timeval atv, rtv, ttv;
598 struct knote *kn, marker;
599 int s, count, timeout, nkev = 0, error = 0;
606 TIMESPEC_TO_TIMEVAL(&atv, tsp);
607 if (itimerfix(&atv)) {
611 if (tsp->tv_sec == 0 && tsp->tv_nsec == 0)
614 timeout = atv.tv_sec > 24 * 60 * 60 ?
615 24 * 60 * 60 * hz : tvtohz(&atv);
616 getmicrouptime(&rtv);
617 timevaladd(&atv, &rtv);
626 if (atv.tv_sec || atv.tv_usec) {
627 getmicrouptime(&rtv);
628 if (timevalcmp(&rtv, &atv, >=))
631 timevalsub(&ttv, &rtv);
632 timeout = ttv.tv_sec > 24 * 60 * 60 ?
633 24 * 60 * 60 * hz : tvtohz(&ttv);
639 if (kq->kq_count == 0) {
643 kq->kq_state |= KQ_SLEEP;
644 error = tsleep(kq, PSOCK | PCATCH, "kqread", timeout);
649 /* don't restart after signals... */
650 if (error == ERESTART)
652 else if (error == EWOULDBLOCK)
657 TAILQ_INSERT_TAIL(&kq->kq_head, &marker, kn_tqe);
659 kn = TAILQ_FIRST(&kq->kq_head);
660 TAILQ_REMOVE(&kq->kq_head, kn, kn_tqe);
663 if (count == maxevents)
667 if (kn->kn_status & KN_DISABLED) {
668 kn->kn_status &= ~KN_QUEUED;
672 if ((kn->kn_flags & EV_ONESHOT) == 0 &&
673 kn->kn_fop->f_event(kn, 0) == 0) {
674 kn->kn_status &= ~(KN_QUEUED | KN_ACTIVE);
678 *kevp = kn->kn_kevent;
681 if (kn->kn_flags & EV_ONESHOT) {
682 kn->kn_status &= ~KN_QUEUED;
685 kn->kn_fop->f_detach(kn);
688 } else if (kn->kn_flags & EV_CLEAR) {
691 kn->kn_status &= ~(KN_QUEUED | KN_ACTIVE);
694 TAILQ_INSERT_TAIL(&kq->kq_head, kn, kn_tqe);
697 if (nkev == KQ_NEVENTS) {
699 error = copyout((caddr_t)&kq->kq_kev, (caddr_t)ulistp,
700 sizeof(struct kevent) * nkev);
709 TAILQ_REMOVE(&kq->kq_head, &marker, kn_tqe);
713 error = copyout((caddr_t)&kq->kq_kev, (caddr_t)ulistp,
714 sizeof(struct kevent) * nkev);
715 p->p_retval[0] = maxevents - count;
721 * This could be expanded to call kqueue_scan, if desired.
725 kqueue_read(struct file *fp, struct uio *uio, struct ucred *cred,
726 int flags, struct proc *p)
733 kqueue_write(struct file *fp, struct uio *uio, struct ucred *cred,
734 int flags, struct proc *p)
741 kqueue_ioctl(struct file *fp, u_long com, caddr_t data, struct proc *p)
748 kqueue_poll(struct file *fp, int events, struct ucred *cred, struct proc *p)
750 struct kqueue *kq = (struct kqueue *)fp->f_data;
754 if (events & (POLLIN | POLLRDNORM)) {
756 revents |= events & (POLLIN | POLLRDNORM);
758 selrecord(p, &kq->kq_sel);
759 kq->kq_state |= KQ_SEL;
768 kqueue_stat(struct file *fp, struct stat *st, struct proc *p)
770 struct kqueue *kq = (struct kqueue *)fp->f_data;
772 bzero((void *)st, sizeof(*st));
773 st->st_size = kq->kq_count;
774 st->st_blksize = sizeof(struct kevent);
775 st->st_mode = S_IFIFO;
781 kqueue_close(struct file *fp, struct proc *p)
783 struct kqueue *kq = (struct kqueue *)fp->f_data;
784 struct filedesc *fdp = p->p_fd;
785 struct knote **knp, *kn, *kn0;
788 for (i = 0; i < fdp->fd_knlistsize; i++) {
789 knp = &SLIST_FIRST(&fdp->fd_knlist[i]);
792 kn0 = SLIST_NEXT(kn, kn_link);
793 if (kq == kn->kn_kq) {
794 kn->kn_fop->f_detach(kn);
799 knp = &SLIST_NEXT(kn, kn_link);
804 if (fdp->fd_knhashmask != 0) {
805 for (i = 0; i < fdp->fd_knhashmask + 1; i++) {
806 knp = &SLIST_FIRST(&fdp->fd_knhash[i]);
809 kn0 = SLIST_NEXT(kn, kn_link);
810 if (kq == kn->kn_kq) {
811 kn->kn_fop->f_detach(kn);
812 /* XXX non-fd release of kn->kn_ptr */
816 knp = &SLIST_NEXT(kn, kn_link);
829 kqueue_wakeup(struct kqueue *kq)
832 if (kq->kq_state & KQ_SLEEP) {
833 kq->kq_state &= ~KQ_SLEEP;
836 if (kq->kq_state & KQ_SEL) {
837 kq->kq_state &= ~KQ_SEL;
838 selwakeup(&kq->kq_sel);
840 KNOTE(&kq->kq_sel.si_note, 0);
844 * walk down a list of knotes, activating them if their event has triggered.
847 knote(struct klist *list, long hint)
851 SLIST_FOREACH(kn, list, kn_selnext)
852 if (kn->kn_fop->f_event(kn, hint))
857 * remove all knotes from a specified klist
860 knote_remove(struct proc *p, struct klist *list)
864 while ((kn = SLIST_FIRST(list)) != NULL) {
865 kn->kn_fop->f_detach(kn);
871 * remove all knotes referencing a specified fd
874 knote_fdclose(struct proc *p, int fd)
876 struct filedesc *fdp = p->p_fd;
877 struct klist *list = &fdp->fd_knlist[fd];
879 knote_remove(p, list);
883 knote_attach(struct knote *kn, struct filedesc *fdp)
888 if (! kn->kn_fop->f_isfd) {
889 if (fdp->fd_knhashmask == 0)
890 fdp->fd_knhash = hashinit(KN_HASHSIZE, M_KQUEUE,
891 &fdp->fd_knhashmask);
892 list = &fdp->fd_knhash[KN_HASH(kn->kn_id, fdp->fd_knhashmask)];
896 if (fdp->fd_knlistsize <= kn->kn_id) {
897 size = fdp->fd_knlistsize;
898 while (size <= kn->kn_id)
900 MALLOC(list, struct klist *,
901 size * sizeof(struct klist *), M_KQUEUE, M_WAITOK);
902 bcopy((caddr_t)fdp->fd_knlist, (caddr_t)list,
903 fdp->fd_knlistsize * sizeof(struct klist *));
904 bzero((caddr_t)list +
905 fdp->fd_knlistsize * sizeof(struct klist *),
906 (size - fdp->fd_knlistsize) * sizeof(struct klist *));
907 if (fdp->fd_knlist != NULL)
908 FREE(fdp->fd_knlist, M_KQUEUE);
909 fdp->fd_knlistsize = size;
910 fdp->fd_knlist = list;
912 list = &fdp->fd_knlist[kn->kn_id];
914 SLIST_INSERT_HEAD(list, kn, kn_link);
919 * should be called at spl == 0, since we don't want to hold spl
920 * while calling fdrop and free.
923 knote_drop(struct knote *kn, struct proc *p)
925 struct filedesc *fdp = p->p_fd;
928 if (kn->kn_fop->f_isfd)
929 list = &fdp->fd_knlist[kn->kn_id];
931 list = &fdp->fd_knhash[KN_HASH(kn->kn_id, fdp->fd_knhashmask)];
933 SLIST_REMOVE(list, kn, knote, kn_link);
934 if (kn->kn_status & KN_QUEUED)
936 if (kn->kn_fop->f_isfd)
943 knote_enqueue(struct knote *kn)
945 struct kqueue *kq = kn->kn_kq;
948 KASSERT((kn->kn_status & KN_QUEUED) == 0, ("knote already queued"));
950 TAILQ_INSERT_TAIL(&kq->kq_head, kn, kn_tqe);
951 kn->kn_status |= KN_QUEUED;
958 knote_dequeue(struct knote *kn)
960 struct kqueue *kq = kn->kn_kq;
963 KASSERT(kn->kn_status & KN_QUEUED, ("knote not queued"));
965 TAILQ_REMOVE(&kq->kq_head, kn, kn_tqe);
966 kn->kn_status &= ~KN_QUEUED;
974 knote_zone = zinit("KNOTE", sizeof(struct knote), 0, 0, 1);
976 SYSINIT(knote, SI_SUB_PSEUDO, SI_ORDER_ANY, knote_init, NULL)
978 static struct knote *
981 return ((struct knote *)zalloc(knote_zone));
985 knote_free(struct knote *kn)
987 zfree(knote_zone, kn);