bsd/kern/kern_event.c

105 static inline void kqlock(struct kqueue *kq);
106 static inline void kqunlock(struct kqueue *kq);
108 static int	kqlock2knoteuse(struct kqueue *kq, struct knote *kn);
109 static int	kqlock2knoteusewait(struct kqueue *kq, struct knote *kn);
110 static int	kqlock2knotedrop(struct kqueue *kq, struct knote *kn);
111 static int	knoteuse2kqlock(struct kqueue *kq, struct knote *kn);
113 static void 	kqueue_wakeup(struct kqueue *kq, int closed);
144 static int	kevent_callback(struct kqueue *kq, struct kevent64_s *kevp, void *data);
145 static void	kevent_continue(struct kqueue *kq, void *data, int error);
147 static int	kqueue_process(struct kqueue *kq, kevent_callback_t callback,
149 static int	kqueue_begin_processing(struct kqueue *kq);
150 static void	kqueue_end_processing(struct kqueue *kq);
299 kqlock(struct kqueue *kq)
301 	lck_spin_lock(&kq->kq_lock);
305 kqunlock(struct kqueue *kq)
307 	lck_spin_unlock(&kq->kq_lock);
311  * Convert a kq lock to a knote use referece.
317  *	- kq locked at entry
321 kqlock2knoteuse(struct kqueue *kq, struct knote *kn)
326 	kqunlock(kq);
331  * Convert a kq lock to a knote use referece,
338  *	- kq locked at entry
339  *	- kq always unlocked on exit
342 kqlock2knoteusewait(struct kqueue *kq, struct knote *kn)
346 		wait_queue_assert_wait((wait_queue_t)kq->kq_wqs, &kn->kn_status, THREAD_UNINT, 0);
347 		kqunlock(kq);
352 	kqunlock(kq);
358  * Convert from a knote use reference back to kq lock.
368 knoteuse2kqlock(struct kqueue *kq, struct knote *kn)
370 	kqlock(kq);
377 			wait_queue_wakeup_all((wait_queue_t)kq->kq_wqs, &kn->kn_status, THREAD_AWAKENED);
384  * Convert a kq lock to a knote drop referece.
392  *	- kq locked at entry
398 kqlock2knotedrop(struct kqueue *kq, struct knote *kn)
406 			kqunlock(kq);
411 	wait_queue_assert_wait((wait_queue_t)kq->kq_wqs, &kn->kn_status, THREAD_UNINT, 0);
412 	kqunlock(kq);
423 	struct kqueue *kq = kn->kn_kq;
425 	kqlock(kq);
429 			wait_queue_wakeup_all((wait_queue_t)kq->kq_wqs, &kn->kn_status, THREAD_AWAKENED);
432 	kqunlock(kq);
453 	struct kqueue *kq = (struct kqueue *)kn->kn_fp->f_data;
455 	kqlock(kq);
456 	KNOTE_DETACH(&kq->kq_sel.si_note, kn);
457 	kqunlock(kq);
464 	struct kqueue *kq = (struct kqueue *)kn->kn_fp->f_data;
466 	kn->kn_data = kq->kq_count;
771 		struct kqueue *kq = kn->kn_kq;
772 		wait_queue_wakeup_all((wait_queue_t)kq->kq_wqs, &kn->kn_hook,
786 	struct kqueue *kq = kn->kn_kq;
798 			wait_queue_assert_wait((wait_queue_t)kq->kq_wqs,
1058 	struct kqueue *kq;
1060 	MALLOC_ZONE(kq, struct kqueue *, sizeof(struct kqueue), M_KQUEUE, M_WAITOK);
1061 	if (kq != NULL) {
1066 			bzero(kq, sizeof(struct kqueue));
1067 			lck_spin_init(&kq->kq_lock, kq_lck_grp, kq_lck_attr);
1068 			TAILQ_INIT(&kq->kq_head);
1069 			kq->kq_wqs = wqs;
1070 			kq->kq_p = p;
1072 			FREE_ZONE(kq, sizeof(struct kqueue), M_KQUEUE);
1079 			fdp->fd_knlistsize = 0;		/* this process has had a kq */
1083 	return kq;
1102 kqueue_dealloc(struct kqueue *kq)
1104 	struct proc *p = kq->kq_p;
1113 			if (kq == kn->kn_kq) {
1114 				kqlock(kq);
1117 				if (kqlock2knotedrop(kq, kn)) {
1133 				if (kq == kn->kn_kq) {
1134 					kqlock(kq);
1137 					if (kqlock2knotedrop(kq, kn)) {
1156 	wait_queue_unlink_all((wait_queue_t)kq->kq_wqs);
1157 	wait_queue_set_free(kq->kq_wqs);
1158 	lck_spin_destroy(&kq->kq_lock, kq_lck_grp);
1159 	FREE_ZONE(kq, sizeof(struct kqueue), M_KQUEUE);
1165 	struct kqueue *kq;
1174 	kq = kqueue_alloc(p);
1175 	if (kq == NULL) {
1183 	fp->f_data = (caddr_t)kq;
1283  *	assume we inherit a use count on the kq fileglob.
1287 kevent_continue(__unused struct kqueue *kq, void *data, int error)
1356 	struct kqueue *kq;
1388 	/* get a usecount for the kq itself */
1389 	if ((error = fp_getfkq(p, fd, &fp, &kq)) != 0)
1392 	/* each kq should only be used for events of one type */
1393 	kqlock(kq);
1394 	if (kq->kq_state & (KQ_KEV32 | KQ_KEV64)) {
1395 		if (((iskev64 && (kq->kq_state & KQ_KEV32)) ||
1396 			(!iskev64 && (kq->kq_state & KQ_KEV64)))) {
1398 			kqunlock(kq);
1402 		kq->kq_state |= (iskev64 ? KQ_KEV64 : KQ_KEV32);
1404 	kqunlock(kq);
1414 		error = kevent_register(kq, &kev, p);
1439 		error = kqueue_scan(kq, kevent_callback,
1442 	kevent_continue(kq, cont_args, error);
1458 kevent_callback(__unused struct kqueue *kq, struct kevent64_s *kevp,
1522 kevent_register(struct kqueue *kq, struct kevent64_s *kev, __unused struct proc *ctxp)
1524 	struct proc *p = kq->kq_p;
1557 				if (kq == kn->kn_kq &&
1570 				    kq == kn->kn_kq &&
1588 			kn->kn_kq = kq;
1589 			kn->kn_tq = &kq->kq_head;
1619 			kqlock(kq);
1628 				kqunlock(kq);
1637 				kqunlock(kq);
1643 			kqunlock(kq);
1651 		kqlock(kq);
1657 			if (kqlock2knotedrop(kq, kn)) {
1693 		if (!kqlock2knoteusewait(kq, kn)) {
1713 		if (knoteuse2kqlock(kq, kn))
1715 		kqunlock(kq);
1747 	struct kqueue *kq = kn->kn_kq;
1782 			if (kqlock2knoteuse(kq, kn)) {
1795 				if (!knoteuse2kqlock(kq, kn)) {
1821 	assert(kn->kn_tq == &kq->kq_head);
1822 	TAILQ_REMOVE(&kq->kq_head, kn, kn_tqe);
1839 		if (kqlock2knotedrop(kq, kn)) {
1857 		kqunlock(kq);
1862 		 * the kq queue and wakeup any
1865 		kqunlock(kq);
1869 	error = (callback)(kq, &kev, data);
1871 	kqlock(kq);
1883 kqueue_begin_processing(struct kqueue *kq)
1886 		if (kq->kq_count == 0) {
1891 		if (kq->kq_nprocess != 0) {
1892 			wait_queue_assert_wait((wait_queue_t)kq->kq_wqs, &kq->kq_nprocess, THREAD_UNINT, 0);
1893 			kq->kq_state |= KQ_PROCWAIT;
1894 			kqunlock(kq);
1896 			kqlock(kq);
1898 			kq->kq_nprocess = 1;
1908 kqueue_end_processing(struct kqueue *kq)
1910 	kq->kq_nprocess = 0;
1911 	if (kq->kq_state & KQ_PROCWAIT) {
1912 		kq->kq_state &= ~KQ_PROCWAIT;
1913 		wait_queue_wakeup_all((wait_queue_t)kq->kq_wqs, &kq->kq_nprocess, THREAD_AWAKENED);
1933 kqueue_process(struct kqueue *kq,
1946 	if (kqueue_begin_processing(kq) == -1) {
1956 	wait_queue_sub_clearrefs(kq->kq_wqs);
1967 	       (kn = TAILQ_FIRST(&kq->kq_head)) != NULL) {
1978 	 * kq's queue and wake up any waiters.
1983 		kn->kn_tq = &kq->kq_head;
1984 		TAILQ_INSERT_TAIL(&kq->kq_head, kn, kn_tqe);
1987 	kqueue_end_processing(kq);
2000 	struct kqueue *kq = (struct kqueue *)data;
2007 		kqlock(kq);
2008 		error = kqueue_process(kq, cont_args->call, cont_args, &count, current_proc());
2010 			wait_queue_assert_wait((wait_queue_t)kq->kq_wqs, KQ_EVENT,
2012 			kq->kq_state |= KQ_SLEEP;
2013 			kqunlock(kq);
2014 			thread_block_parameter(kqueue_scan_continue, kq);
2017 		kqunlock(kq);
2032 	(cont_args->cont)(kq, cont_args->data, error);
2047  *	The caller must hold a use-count reference on the kq.
2051 kqueue_scan(struct kqueue *kq,
2071 		 * Make a pass through the kq to find events already
2074 		kqlock(kq);
2075 		error = kqueue_process(kq, callback, data, &count, p);
2114 		wait_queue_assert_wait((wait_queue_t)kq->kq_wqs, KQ_EVENT, THREAD_ABORTSAFE, deadline);
2115 		kq->kq_state |= KQ_SLEEP;
2116 		kqunlock(kq);
2117 		wait_result = thread_block_parameter(cont, kq);
2133 	kqunlock(kq);
2176 	struct kqueue *kq = (struct kqueue *)fp->f_data;
2186 	kqlock(kq);
2199 		kq->kq_state |= KQ_SEL;
2200 		wait_queue_link_noalloc((wait_queue_t)kq->kq_wqs, ut->uu_wqset,
2204 	if (kqueue_begin_processing(kq) == -1) {
2205 		kqunlock(kq);
2209 	if (kq->kq_count != 0) {
2217 		while ((kn = (struct knote*)TAILQ_FIRST(&kq->kq_head)) != NULL) {
2223 			TAILQ_REMOVE(&kq->kq_head, kn, kn_tqe);
2226 			if (kqlock2knoteuse(kq, kn)) {
2230 				if (knoteuse2kqlock(kq, kn)) {
2246 		kn->kn_tq = &kq->kq_head;
2247 		TAILQ_INSERT_TAIL(&kq->kq_head, kn, kn_tqe);
2250 	kqueue_end_processing(kq);
2251 	kqunlock(kq);
2262 	struct kqueue *kq = (struct kqueue *)fg->fg_data;
2264 	kqueue_dealloc(kq);
2278 	struct kqueue *kq = (struct kqueue *)kn->kn_fp->f_data;
2281 	if (parentkq == kq ||
2298 	    parentkq->kq_level < kq->kq_level)
2306 		if (parentkq->kq_level < kq->kq_level + 1)
2307 			parentkq->kq_level = kq->kq_level + 1;
2311 		kqlock(kq);
2312 		KNOTE_ATTACH(&kq->kq_sel.si_note, kn);
2314 		if (kq->kq_level == 0)
2315 			kq->kq_level = 1;
2316 		kqunlock(kq);
2322  * kqueue_drain - called when kq is closed
2328 	struct kqueue *kq = (struct kqueue *)fp->f_fglob->fg_data;
2329 	kqlock(kq);
2330 	kqueue_wakeup(kq, 1);
2331 	kqunlock(kq);
2340 	struct kqueue *kq = (struct kqueue *)fp->f_data;
2345 		sb64->st_size = kq->kq_count;
2346 		if (kq->kq_state & KQ_KEV64)
2355 		sb->st_size = kq->kq_count;
2356 		if (kq->kq_state & KQ_KEV64)
2370 kqueue_wakeup(struct kqueue *kq, int closed)
2372 	if ((kq->kq_state & (KQ_SLEEP | KQ_SEL)) != 0 || kq->kq_nprocess > 0) {
2373 		kq->kq_state &= ~(KQ_SLEEP | KQ_SEL);
2374 		wait_queue_wakeup_all((wait_queue_t)kq->kq_wqs, KQ_EVENT,
2404 		struct kqueue *kq = kn->kn_kq;
2406 		kqlock(kq);
2407 		if (kqlock2knoteuse(kq, kn)) {
2414 			if (knoteuse2kqlock(kq, kn) && result)
2418 		kqunlock(kq);
2458 	struct kqueue *kq = kn->kn_kq;
2461 	kr = wait_queue_link_noalloc(wq, kq->kq_wqs, wql);
2482 	struct kqueue *kq = kn->kn_kq;
2485 	kr = wait_queue_unlink_nofree(wq, kq->kq_wqs, wqlp);
2486 	kqlock(kq);
2489 	kqunlock(kq);
2511 		struct kqueue *kq = kn->kn_kq;
2513 		if (kq->kq_p != p)
2514 			panic("knote_fdclose: proc mismatch (kq->kq_p=%p != p=%p)", kq->kq_p, p);
2516 		kqlock(kq);
2526 		if (kqlock2knotedrop(kq, kn)) {
2594 	struct kqueue *kq = kn->kn_kq;
2595 	struct proc *p = kq->kq_p;
2607 	kqlock(kq);
2610 	kqunlock(kq);
2614 		wait_queue_wakeup_all((wait_queue_t)kq->kq_wqs, &kn->kn_status, THREAD_AWAKENED);
2626 	struct kqueue *kq = kn->kn_kq;
2630 	kqueue_wakeup(kq, 0);
2632 	/* this is a real event: wake up the parent kq, too */
2634 		KNOTE(&kq->kq_sel.si_note, 0);
2652 		struct kqueue *kq = kn->kn_kq;
2656 		kq->kq_count++;
2664 	struct kqueue *kq = kn->kn_kq;
2670 		kn->kn_tq = &kq->kq_head;
2672 		kq->kq_count--;
2681 	/* allocate kq lock group attribute and group */
2686 	/* Allocate kq lock attribute */
2986 fill_kqueueinfo(struct kqueue *kq, struct kqueue_info * kinfo)
2994 	st->vst_size = kq->kq_count;
2995 	if (kq->kq_state & KQ_KEV64)
3000 	if (kq->kq_state & KQ_SEL)
3002 	if (kq->kq_state & KQ_SLEEP)