diff options
Diffstat (limited to 'freebsd/sys/kern/kern_event.c')
| -rw-r--r-- | freebsd/sys/kern/kern_event.c | 116 |
1 files changed, 106 insertions, 10 deletions
diff --git a/freebsd/sys/kern/kern_event.c b/freebsd/sys/kern/kern_event.c index 33fca549..25a9518f 100644 --- a/freebsd/sys/kern/kern_event.c +++ b/freebsd/sys/kern/kern_event.c @@ -179,6 +179,10 @@ static int filt_fileattach(struct knote *kn); static void filt_timerexpire(void *knx); static int filt_timerattach(struct knote *kn); static void filt_timerdetach(struct knote *kn); +static void filt_timerstart(struct knote *kn, sbintime_t to); +static void filt_timertouch(struct knote *kn, struct kevent *kev, + u_long type); +static int filt_timervalidate(struct knote *kn, sbintime_t *to); static int filt_timer(struct knote *kn, long hint); static int filt_userattach(struct knote *kn); static void filt_userdetach(struct knote *kn); @@ -209,6 +213,7 @@ static struct filterops timer_filtops = { .f_attach = filt_timerattach, .f_detach = filt_timerdetach, .f_event = filt_timer, + .f_touch = filt_timertouch, }; static struct filterops user_filtops = { .f_attach = filt_userattach, @@ -738,29 +743,44 @@ filt_timerexpire(void *knx) * data contains amount of time to sleep */ static int -filt_timerattach(struct knote *kn) +filt_timervalidate(struct knote *kn, sbintime_t *to) { - struct kq_timer_cb_data *kc; struct bintime bt; - sbintime_t to, sbt; - unsigned int ncallouts; + sbintime_t sbt; if (kn->kn_sdata < 0) return (EINVAL); if (kn->kn_sdata == 0 && (kn->kn_flags & EV_ONESHOT) == 0) kn->kn_sdata = 1; - /* Only precision unit are supported in flags so far */ + /* + * The only fflags values supported are the timer unit + * (precision) and the absolute time indicator. + */ if ((kn->kn_sfflags & ~(NOTE_TIMER_PRECMASK | NOTE_ABSTIME)) != 0) return (EINVAL); - to = timer2sbintime(kn->kn_sdata, kn->kn_sfflags); + *to = timer2sbintime(kn->kn_sdata, kn->kn_sfflags); if ((kn->kn_sfflags & NOTE_ABSTIME) != 0) { getboottimebin(&bt); sbt = bttosbt(bt); - to -= sbt; + *to -= sbt; } - if (to < 0) + if (*to < 0) return (EINVAL); + return (0); +} + +static int +filt_timerattach(struct knote *kn) +{ + struct kq_timer_cb_data *kc; + sbintime_t to; + unsigned int ncallouts; + int error; + + error = filt_timervalidate(kn, &to); + if (error != 0) + return (error); do { ncallouts = kq_ncallouts; @@ -773,6 +793,17 @@ filt_timerattach(struct knote *kn) kn->kn_status &= ~KN_DETACHED; /* knlist_add clears it */ kn->kn_ptr.p_v = kc = malloc(sizeof(*kc), M_KQUEUE, M_WAITOK); callout_init(&kc->c, 1); + filt_timerstart(kn, to); + + return (0); +} + +static void +filt_timerstart(struct knote *kn, sbintime_t to) +{ + struct kq_timer_cb_data *kc; + + kc = kn->kn_ptr.p_v; if ((kn->kn_sfflags & NOTE_ABSTIME) != 0) { kc->next = to; kc->to = 0; @@ -782,8 +813,6 @@ filt_timerattach(struct knote *kn) } callout_reset_sbt_on(&kc->c, kc->next, 0, filt_timerexpire, kn, PCPU_GET(cpuid), C_ABSOLUTE); - - return (0); } static void @@ -800,6 +829,73 @@ filt_timerdetach(struct knote *kn) kn->kn_status |= KN_DETACHED; /* knlist_remove sets it */ } +static void +filt_timertouch(struct knote *kn, struct kevent *kev, u_long type) +{ + struct kq_timer_cb_data *kc; + struct kqueue *kq; + sbintime_t to; + int error; + + switch (type) { + case EVENT_REGISTER: + /* Handle re-added timers that update data/fflags */ + if (kev->flags & EV_ADD) { + kc = kn->kn_ptr.p_v; + + /* Drain any existing callout. */ + callout_drain(&kc->c); + + /* Throw away any existing undelivered record + * of the timer expiration. This is done under + * the presumption that if a process is + * re-adding this timer with new parameters, + * it is no longer interested in what may have + * happened under the old parameters. If it is + * interested, it can wait for the expiration, + * delete the old timer definition, and then + * add the new one. + * + * This has to be done while the kq is locked: + * - if enqueued, dequeue + * - make it no longer active + * - clear the count of expiration events + */ + kq = kn->kn_kq; + KQ_LOCK(kq); + if (kn->kn_status & KN_QUEUED) + knote_dequeue(kn); + + kn->kn_status &= ~KN_ACTIVE; + kn->kn_data = 0; + KQ_UNLOCK(kq); + + /* Reschedule timer based on new data/fflags */ + kn->kn_sfflags = kev->fflags; + kn->kn_sdata = kev->data; + error = filt_timervalidate(kn, &to); + if (error != 0) { + kn->kn_flags |= EV_ERROR; + kn->kn_data = error; + } else + filt_timerstart(kn, to); + } + break; + + case EVENT_PROCESS: + *kev = kn->kn_kevent; + if (kn->kn_flags & EV_CLEAR) { + kn->kn_data = 0; + kn->kn_fflags = 0; + } + break; + + default: + panic("filt_timertouch() - invalid type (%ld)", type); + break; + } +} + static int filt_timer(struct knote *kn, long hint) { |