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Diffstat (limited to 'freebsd/sys/kern/kern_event.c')
-rw-r--r--freebsd/sys/kern/kern_event.c131
1 files changed, 91 insertions, 40 deletions
diff --git a/freebsd/sys/kern/kern_event.c b/freebsd/sys/kern/kern_event.c
index 69c47246..89cd1765 100644
--- a/freebsd/sys/kern/kern_event.c
+++ b/freebsd/sys/kern/kern_event.c
@@ -464,8 +464,11 @@ filt_proc(struct knote *kn, long hint)
if (!(kn->kn_status & KN_DETACHED))
knlist_remove_inevent(&p->p_klist, kn);
kn->kn_flags |= (EV_EOF | EV_ONESHOT);
- kn->kn_data = p->p_xstat;
kn->kn_ptr.p_proc = NULL;
+ if (kn->kn_fflags & NOTE_EXIT)
+ kn->kn_data = p->p_xstat;
+ if (kn->kn_fflags == 0)
+ kn->kn_flags |= EV_DROP;
return (1);
}
@@ -497,7 +500,7 @@ knote_fork(struct knlist *list, int pid)
continue;
kq = kn->kn_kq;
KQ_LOCK(kq);
- if ((kn->kn_status & KN_INFLUX) == KN_INFLUX) {
+ if ((kn->kn_status & (KN_INFLUX | KN_SCAN)) == KN_INFLUX) {
KQ_UNLOCK(kq);
continue;
}
@@ -507,7 +510,7 @@ knote_fork(struct knlist *list, int pid)
*/
if ((kn->kn_sfflags & NOTE_TRACK) == 0) {
kn->kn_status |= KN_HASKQLOCK;
- if (kn->kn_fop->f_event(kn, NOTE_FORK | pid))
+ if (kn->kn_fop->f_event(kn, NOTE_FORK))
KNOTE_ACTIVATE(kn, 1);
kn->kn_status &= ~KN_HASKQLOCK;
KQ_UNLOCK(kq);
@@ -535,10 +538,10 @@ knote_fork(struct knlist *list, int pid)
kev.data = kn->kn_id; /* parent */
kev.udata = kn->kn_kevent.udata;/* preserve udata */
error = kqueue_register(kq, &kev, NULL, 0);
- if (kn->kn_fop->f_event(kn, NOTE_FORK | pid))
- KNOTE_ACTIVATE(kn, 0);
if (error)
kn->kn_fflags |= NOTE_TRACKERR;
+ if (kn->kn_fop->f_event(kn, NOTE_FORK))
+ KNOTE_ACTIVATE(kn, 0);
KQ_LOCK(kq);
kn->kn_status &= ~KN_INFLUX;
KQ_UNLOCK_FLUX(kq);
@@ -753,11 +756,11 @@ sys_kqueue(struct thread *td, struct kqueue_args *uap)
#ifndef __rtems__
FILEDESC_XLOCK(fdp);
- SLIST_INSERT_HEAD(&fdp->fd_kqlist, kq, kq_list);
+ TAILQ_INSERT_HEAD(&fdp->fd_kqlist, kq, kq_list);
FILEDESC_XUNLOCK(fdp);
#else /* __rtems__ */
rtems_libio_lock();
- SLIST_INSERT_HEAD(&fd_kqlist, kq, kq_list);
+ TAILQ_INSERT_HEAD(&fd_kqlist, kq, kq_list);
rtems_libio_unlock();
#endif /* __rtems__ */
@@ -1076,12 +1079,13 @@ kqueue_register(struct kqueue *kq, struct kevent *kev, struct thread *td, int wa
struct file *fp;
struct knote *kn, *tkn;
int error, filt, event;
- int haskqglobal;
+ int haskqglobal, filedesc_unlock;
fp = NULL;
kn = NULL;
error = 0;
haskqglobal = 0;
+ filedesc_unlock = 0;
filt = kev->filter;
fops = kqueue_fo_find(filt);
@@ -1125,6 +1129,13 @@ findkn:
goto done;
}
+ /*
+ * Pre-lock the filedesc before the global
+ * lock mutex, see the comment in
+ * kqueue_close().
+ */
+ FILEDESC_XLOCK(td->td_proc->p_fd);
+ filedesc_unlock = 1;
KQ_GLOBAL_LOCK(&kq_global, haskqglobal);
}
@@ -1154,6 +1165,10 @@ findkn:
/* knote is in the process of changing, wait for it to stablize. */
if (kn != NULL && (kn->kn_status & KN_INFLUX) == KN_INFLUX) {
KQ_GLOBAL_UNLOCK(&kq_global, haskqglobal);
+ if (filedesc_unlock) {
+ FILEDESC_XUNLOCK(td->td_proc->p_fd);
+ filedesc_unlock = 0;
+ }
kq->kq_state |= KQ_FLUXWAIT;
msleep(kq, &kq->kq_lock, PSOCK | PDROP, "kqflxwt", 0);
if (fp != NULL) {
@@ -1229,7 +1244,7 @@ findkn:
* but doing so will not reset any filter which has already been
* triggered.
*/
- kn->kn_status |= KN_INFLUX;
+ kn->kn_status |= KN_INFLUX | KN_SCAN;
KQ_UNLOCK(kq);
KN_LIST_LOCK(kn);
kn->kn_kevent.udata = kev->udata;
@@ -1252,7 +1267,7 @@ done_ev_add:
KQ_LOCK(kq);
if (event)
KNOTE_ACTIVATE(kn, 1);
- kn->kn_status &= ~KN_INFLUX;
+ kn->kn_status &= ~(KN_INFLUX | KN_SCAN);
KN_LIST_UNLOCK(kn);
if ((kev->flags & EV_DISABLE) &&
@@ -1270,6 +1285,8 @@ done_ev_add:
done:
KQ_GLOBAL_UNLOCK(&kq_global, haskqglobal);
+ if (filedesc_unlock)
+ FILEDESC_XUNLOCK(td->td_proc->p_fd);
if (fp != NULL)
fdrop(fp, td);
if (tkn != NULL)
@@ -1541,7 +1558,21 @@ start:
KASSERT((kn->kn_status & KN_INFLUX) == 0,
("KN_INFLUX set when not suppose to be"));
- if ((kn->kn_flags & EV_ONESHOT) == EV_ONESHOT) {
+ if ((kn->kn_flags & EV_DROP) == EV_DROP) {
+ kn->kn_status &= ~KN_QUEUED;
+ kn->kn_status |= KN_INFLUX;
+ kq->kq_count--;
+ KQ_UNLOCK(kq);
+ /*
+ * We don't need to lock the list since we've marked
+ * it _INFLUX.
+ */
+ if (!(kn->kn_status & KN_DETACHED))
+ kn->kn_fop->f_detach(kn);
+ knote_drop(kn, td);
+ KQ_LOCK(kq);
+ continue;
+ } else if ((kn->kn_flags & EV_ONESHOT) == EV_ONESHOT) {
kn->kn_status &= ~KN_QUEUED;
kn->kn_status |= KN_INFLUX;
kq->kq_count--;
@@ -1557,7 +1588,7 @@ start:
KQ_LOCK(kq);
kn = NULL;
} else {
- kn->kn_status |= KN_INFLUX;
+ kn->kn_status |= KN_INFLUX | KN_SCAN;
KQ_UNLOCK(kq);
if ((kn->kn_status & KN_KQUEUE) == KN_KQUEUE)
KQ_GLOBAL_LOCK(&kq_global, haskqglobal);
@@ -1566,7 +1597,8 @@ start:
KQ_LOCK(kq);
KQ_GLOBAL_UNLOCK(&kq_global, haskqglobal);
kn->kn_status &=
- ~(KN_QUEUED | KN_ACTIVE | KN_INFLUX);
+ ~(KN_QUEUED | KN_ACTIVE | KN_INFLUX |
+ KN_SCAN);
kq->kq_count--;
KN_LIST_UNLOCK(kn);
influx = 1;
@@ -1596,7 +1628,7 @@ start:
} else
TAILQ_INSERT_TAIL(&kq->kq_head, kn, kn_tqe);
- kn->kn_status &= ~(KN_INFLUX);
+ kn->kn_status &= ~(KN_INFLUX | KN_SCAN);
KN_LIST_UNLOCK(kn);
influx = 1;
}
@@ -1788,6 +1820,7 @@ kqueue_close(struct file *fp, struct thread *td)
struct knote *kn;
int i;
int error;
+ int filedesc_unlock;
#ifdef __rtems__
/* FIXME: Move this to the RTEMS close() function */
@@ -1797,6 +1830,7 @@ kqueue_close(struct file *fp, struct thread *td)
if ((error = kqueue_acquire(fp, &kq)))
return error;
+ filedesc_unlock = 0;
KQ_LOCK(kq);
KASSERT((kq->kq_state & KQ_CLOSING) != KQ_CLOSING,
@@ -1863,12 +1897,24 @@ kqueue_close(struct file *fp, struct thread *td)
KQ_UNLOCK(kq);
#ifndef __rtems__
- FILEDESC_XLOCK(fdp);
- SLIST_REMOVE(&fdp->fd_kqlist, kq, kqueue, kq_list);
- FILEDESC_XUNLOCK(fdp);
+ /*
+ * We could be called due to the knote_drop() doing fdrop(),
+ * called from kqueue_register(). In this case the global
+ * lock is owned, and filedesc sx is locked before, to not
+ * take the sleepable lock after non-sleepable.
+ */
+ if (!sx_xlocked(FILEDESC_LOCK(fdp))) {
+ FILEDESC_XLOCK(fdp);
+ filedesc_unlock = 1;
+ } else
+ filedesc_unlock = 0;
+ TAILQ_REMOVE(&fdp->fd_kqlist, kq, kq_list);
+ if (filedesc_unlock)
+ FILEDESC_XUNLOCK(fdp);
#else /* __rtems__ */
+ (void)filedesc_unlock;
rtems_libio_lock();
- SLIST_REMOVE(&fd_kqlist, kq, kqueue, kq_list);
+ TAILQ_REMOVE(&fd_kqlist, kq, kq_list);
rtems_libio_unlock();
#endif /* __rtems__ */
@@ -1966,28 +2012,33 @@ knote(struct knlist *list, long hint, int lockflags)
*/
SLIST_FOREACH(kn, &list->kl_list, kn_selnext) {
kq = kn->kn_kq;
- if ((kn->kn_status & KN_INFLUX) != KN_INFLUX) {
+ KQ_LOCK(kq);
+ if ((kn->kn_status & (KN_INFLUX | KN_SCAN)) == KN_INFLUX) {
+ /*
+ * Do not process the influx notes, except for
+ * the influx coming from the kq unlock in the
+ * kqueue_scan(). In the later case, we do
+ * not interfere with the scan, since the code
+ * fragment in kqueue_scan() locks the knlist,
+ * and cannot proceed until we finished.
+ */
+ KQ_UNLOCK(kq);
+ } else if ((lockflags & KNF_NOKQLOCK) != 0) {
+ kn->kn_status |= KN_INFLUX;
+ KQ_UNLOCK(kq);
+ error = kn->kn_fop->f_event(kn, hint);
KQ_LOCK(kq);
- if ((kn->kn_status & KN_INFLUX) == KN_INFLUX) {
- KQ_UNLOCK(kq);
- } else if ((lockflags & KNF_NOKQLOCK) != 0) {
- kn->kn_status |= KN_INFLUX;
- KQ_UNLOCK(kq);
- error = kn->kn_fop->f_event(kn, hint);
- KQ_LOCK(kq);
- kn->kn_status &= ~KN_INFLUX;
- if (error)
- KNOTE_ACTIVATE(kn, 1);
- KQ_UNLOCK_FLUX(kq);
- } else {
- kn->kn_status |= KN_HASKQLOCK;
- if (kn->kn_fop->f_event(kn, hint))
- KNOTE_ACTIVATE(kn, 1);
- kn->kn_status &= ~KN_HASKQLOCK;
- KQ_UNLOCK(kq);
- }
+ kn->kn_status &= ~KN_INFLUX;
+ if (error)
+ KNOTE_ACTIVATE(kn, 1);
+ KQ_UNLOCK_FLUX(kq);
+ } else {
+ kn->kn_status |= KN_HASKQLOCK;
+ if (kn->kn_fop->f_event(kn, hint))
+ KNOTE_ACTIVATE(kn, 1);
+ kn->kn_status &= ~KN_HASKQLOCK;
+ KQ_UNLOCK(kq);
}
- kq = NULL;
}
if ((lockflags & KNF_LISTLOCKED) == 0)
list->kl_unlock(list->kl_lockarg);
@@ -2231,11 +2282,11 @@ knote_fdclose(struct thread *td, int fd)
* since filedesc is locked.
*/
#ifndef __rtems__
- SLIST_FOREACH(kq, &fdp->fd_kqlist, kq_list) {
+ TAILQ_FOREACH(kq, &fdp->fd_kqlist, kq_list) {
#else /* __rtems__ */
/* FIXME: Use separate lock? */
rtems_libio_lock();
- SLIST_FOREACH(kq, &fd_kqlist, kq_list) {
+ TAILQ_FOREACH(kq, &fd_kqlist, kq_list) {
#endif /* __rtems__ */
KQ_LOCK(kq);
generated by cgit v1.2.3 (git 2.25.1) at 2024-04-30 18:13:55 +0000