timer.h revision 60063497a95e716c9a689af3be2687d261f115b4 
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
14struct 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
22extern void rpc_init_rtt(struct rpc_rtt *rt, unsigned long timeo);
23extern void rpc_update_rtt(struct rpc_rtt *rt, unsigned timer, long m);
24extern unsigned long rpc_calc_rto(struct rpc_rtt *rt, unsigned timer);
25
26static 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
42static 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