lib/isc/ratelimiter.c

62 	isc_ratelimiter_t *rl;
65 	rl = isc_mem_get(mctx, sizeof(*rl));
66 	*rl = (isc_ratelimiter_t){
73 	isc_refcount_init(&rl->references, 1);
74 	isc_interval_set(&rl->interval, 0, 0);
75 	ISC_LIST_INIT(rl->pending);
77 	isc_mutex_init(&rl->lock);
80 				  rl->task, ratelimiter_tick, rl, &rl->timer);
89 	isc_refcount_increment(&rl->references);
91 	ISC_EVENT_INIT(&rl->shutdownevent, sizeof(isc_event_t), 0, NULL,
93 		       ratelimiter_shutdowncomplete, rl, rl, NULL, NULL);
95 	*ratelimiterp = rl;
99 	isc_refcount_decrementz(&rl->references);
100 	isc_refcount_destroy(&rl->references);
101 	isc_mutex_destroy(&rl->lock);
102 	isc_mem_put(mctx, rl, sizeof(*rl));
107 isc_ratelimiter_setinterval(isc_ratelimiter_t *rl, isc_interval_t *interval) {
110 	REQUIRE(rl != NULL);
113 	LOCK(&rl->lock);
114 	rl->interval = *interval;
118 	if (rl->state == isc_ratelimiter_ratelimited) {
119 		result = isc_timer_reset(rl->timer, isc_timertype_ticker, NULL,
120 					 &rl->interval, false);
122 	UNLOCK(&rl->lock);
127 isc_ratelimiter_setpertic(isc_ratelimiter_t *rl, uint32_t pertic) {
128 	REQUIRE(rl != NULL);
133 	rl->pertic = pertic;
137 isc_ratelimiter_setpushpop(isc_ratelimiter_t *rl, bool pushpop) {
138 	REQUIRE(rl != NULL);
140 	rl->pushpop = pushpop;
144 isc_ratelimiter_enqueue(isc_ratelimiter_t *rl, isc_task_t *task,
149 	REQUIRE(rl != NULL);
155 	LOCK(&rl->lock);
156 	if (rl->state == isc_ratelimiter_ratelimited ||
157 	    rl->state == isc_ratelimiter_stalled)
161 		if (rl->pushpop) {
162 			ISC_LIST_PREPEND(rl->pending, ev, ev_ratelink);
164 			ISC_LIST_APPEND(rl->pending, ev, ev_ratelink);
166 	} else if (rl->state == isc_ratelimiter_idle) {
167 		result = isc_timer_reset(rl->timer, isc_timertype_ticker, NULL,
168 					 &rl->interval, false);
171 			rl->state = isc_ratelimiter_ratelimited;
174 		INSIST(rl->state == isc_ratelimiter_shuttingdown);
177 	UNLOCK(&rl->lock);
185 isc_ratelimiter_dequeue(isc_ratelimiter_t *rl, isc_event_t *event) {
188 	REQUIRE(rl != NULL);
191 	LOCK(&rl->lock);
193 		ISC_LIST_UNLINK(rl->pending, event, ev_ratelink);
198 	UNLOCK(&rl->lock);
204 	isc_ratelimiter_t *rl = (isc_ratelimiter_t *)event->ev_arg;
212 	pertic = rl->pertic;
215 		LOCK(&rl->lock);
216 		p = ISC_LIST_HEAD(rl->pending);
221 			ISC_LIST_UNLINK(rl->pending, p, ev_ratelink);
228 				rl->timer, isc_timertype_inactive, NULL, NULL,
231 			rl->state = isc_ratelimiter_idle;
234 		UNLOCK(&rl->lock);
244 isc_ratelimiter_shutdown(isc_ratelimiter_t *rl) {
249 	REQUIRE(rl != NULL);
251 	LOCK(&rl->lock);
252 	rl->state = isc_ratelimiter_shuttingdown;
253 	(void)isc_timer_reset(rl->timer, isc_timertype_inactive, NULL, NULL,
255 	while ((ev = ISC_LIST_HEAD(rl->pending)) != NULL) {
257 		ISC_LIST_UNLINK(rl->pending, ev, ev_ratelink);
262 	isc_task_attach(rl->task, &task);
264 	result = isc_timer_reset(rl->timer, isc_timertype_inactive, NULL, NULL,
267 	isc_timer_destroy(&rl->timer);
273 	ev = &rl->shutdownevent;
274 	isc_task_send(rl->task, &ev);
276 	UNLOCK(&rl->lock);
281 	isc_ratelimiter_t *rl = (isc_ratelimiter_t *)event->ev_arg;
285 	isc_ratelimiter_detach(&rl);
290 ratelimiter_free(isc_ratelimiter_t *rl) {
291 	isc_refcount_destroy(&rl->references);
292 	isc_mutex_destroy(&rl->lock);
293 	isc_mem_put(rl->mctx, rl, sizeof(*rl));
308 	isc_ratelimiter_t *rl;
312 	rl = *rlp;
315 	if (isc_refcount_decrement(&rl->references) == 1) {
316 		ratelimiter_free(rl);
321 isc_ratelimiter_stall(isc_ratelimiter_t *rl) {
324 	REQUIRE(rl != NULL);
326 	LOCK(&rl->lock);
327 	switch (rl->state) {
332 		result = isc_timer_reset(rl->timer, isc_timertype_inactive,
338 		rl->state = isc_ratelimiter_stalled;
341 	UNLOCK(&rl->lock);
346 isc_ratelimiter_release(isc_ratelimiter_t *rl) {
349 	REQUIRE(rl != NULL);
351 	LOCK(&rl->lock);
352 	switch (rl->state) {
357 		if (!ISC_LIST_EMPTY(rl->pending)) {
358 			result = isc_timer_reset(rl->timer,
360 						 &rl->interval, false);
362 				rl->state = isc_ratelimiter_ratelimited;
365 			rl->state = isc_ratelimiter_idle;
372 	UNLOCK(&rl->lock);