1 // SPDX-License-Identifier: GPL-2.0-only
3  * ratelimit.c - Do something with rate limit.
7  * 2008-05-01 rewrite the function and use a ratelimit_state data struct as
16  * __ratelimit - rate limiting
17  * @rs: ratelimit_state data
20  * This enforces a rate limit: not more than @rs->burst callbacks
21  * in every @rs->interval
27 int ___ratelimit(struct ratelimit_state *rs, const char *func)  in ___ratelimit()  argument
33 	int interval = READ_ONCE(rs->interval);  in ___ratelimit()
34 	int burst = READ_ONCE(rs->burst);  in ___ratelimit()
47 	if (!raw_spin_trylock_irqsave(&rs->lock, flags))  in ___ratelimit()
50 	if (!rs->begin)  in ___ratelimit()
51 		rs->begin = jiffies;  in ___ratelimit()
53 	if (time_is_before_jiffies(rs->begin + interval)) {  in ___ratelimit()
54 		if (rs->missed) {  in ___ratelimit()
55 			if (!(rs->flags & RATELIMIT_MSG_ON_RELEASE)) {  in ___ratelimit()
58 						func, rs->missed);  in ___ratelimit()
59 				rs->missed = 0;  in ___ratelimit()
62 		rs->begin   = jiffies;  in ___ratelimit()
63 		rs->printed = 0;  in ___ratelimit()
65 	if (burst && burst > rs->printed) {  in ___ratelimit()
66 		rs->printed++;  in ___ratelimit()
69 		rs->missed++;  in ___ratelimit()
72 	raw_spin_unlock_irqrestore(&rs->lock, flags);  in ___ratelimit()