LXR linux/include/linux/sunrpc/timer.h

   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