1 /*
2  *  linux/include/linux/sunrpc/timer.h
3  *
4  *  Declarations for the RPC transport timer.
5  *
6  *  Copyright (C) 2002 Trond Myklebust <trond.myklebust@fys.uio.no>
7  */
8 
9 #ifndef _LINUX_SUNRPC_TIMER_H
10 #define _LINUX_SUNRPC_TIMER_H
11 
12 #include <linux/atomic.h>
13 
14 struct rpc_rtt {
15 	unsigned long timeo;	/* default timeout value */
16 	unsigned long srtt[5];	/* smoothed round trip time << 3 */
17 	unsigned long sdrtt[5];	/* smoothed medium deviation of RTT */
18 	int ntimeouts[5];	/* Number of timeouts for the last request */
19 };
20 
21 
22 extern void rpc_init_rtt(struct rpc_rtt *rt, unsigned long timeo);
23 extern void rpc_update_rtt(struct rpc_rtt *rt, unsigned timer, long m);
24 extern unsigned long rpc_calc_rto(struct rpc_rtt *rt, unsigned timer);
25 
rpc_set_timeo(struct rpc_rtt * rt,int timer,int ntimeo)26 static inline void rpc_set_timeo(struct rpc_rtt *rt, int timer, int ntimeo)
27 {
28 	int *t;
29 	if (!timer)
30 		return;
31 	t = &rt->ntimeouts[timer-1];
32 	if (ntimeo < *t) {
33 		if (*t > 0)
34 			(*t)--;
35 	} else {
36 		if (ntimeo > 8)
37 			ntimeo = 8;
38 		*t = ntimeo;
39 	}
40 }
41 
rpc_ntimeo(struct rpc_rtt * rt,int timer)42 static inline int rpc_ntimeo(struct rpc_rtt *rt, int timer)
43 {
44 	if (!timer)
45 		return 0;
46 	return rt->ntimeouts[timer-1];
47 }
48 
49 #endif /* _LINUX_SUNRPC_TIMER_H */
50