libcfs/include/libcfs/libcfs_time.h

   1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
   2  * vim:expandtab:shiftwidth=8:tabstop=8:
   3  *
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   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 only,
  10  * as published by the Free Software Foundation.
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  12  * This program is distributed in the hope that it will be useful, but
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  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * General Public License version 2 for more details (a copy is included
  16  * in the LICENSE file that accompanied this code).
  17  *
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  28 /*
  29  * Copyright  2008 Sun Microsystems, Inc. All rights reserved
  30  * Use is subject to license terms.
  31  */
  32 /*
  33  * This file is part of Lustre, http://www.lustre.org/
  34  * Lustre is a trademark of Sun Microsystems, Inc.
  35  *
  36  * libcfs/include/libcfs/libcfs_time.h
  37  *
  38  * Time functions.
  39  *
  40  */
  41
  42 #ifndef __LIBCFS_TIME_H__
  43 #define __LIBCFS_TIME_H__
  44 /*
  45  * generic time manipulation functions.
  46  */
  47
  48 static inline cfs_time_t cfs_time_add(cfs_time_t t, cfs_duration_t d)
  49 {
  50         return (cfs_time_t)(t + d);
  51 }
  52
  53 static inline cfs_duration_t cfs_time_sub(cfs_time_t t1, cfs_time_t t2)
  54 {
  55         return (cfs_time_t)(t1 - t2);
  56 }
  57
  58 static inline int cfs_time_after(cfs_time_t t1, cfs_time_t t2)
  59 {
  60         return cfs_time_before(t2, t1);
  61 }
  62
  63 static inline int cfs_time_aftereq(cfs_time_t t1, cfs_time_t t2)
  64 {
  65         return cfs_time_beforeq(t2, t1);
  66 }
  67
  68
  69 static inline cfs_time_t cfs_time_shift(int seconds)
  70 {
  71         return cfs_time_add(cfs_time_current(), cfs_time_seconds(seconds));
  72 }
  73
  74 static inline long cfs_timeval_sub(struct timeval *large, struct timeval *small,
  75                                    struct timeval *result)
  76 {
  77         long r = (long) (
  78                 (large->tv_sec - small->tv_sec) * ONE_MILLION +
  79                 (large->tv_usec - small->tv_usec));
  80         if (result != NULL) {
  81                 result->tv_usec = r % ONE_MILLION;
  82                 result->tv_sec = r / ONE_MILLION;
  83         }
  84         return r;
  85 }
  86
  87 static inline void cfs_slow_warning(cfs_time_t now, int seconds, char *msg)
  88 {
  89         if (cfs_time_after(cfs_time_current(),
  90                            cfs_time_add(now, cfs_time_seconds(15))))
  91                 CERROR("slow %s "CFS_TIME_T" sec\n", msg,
  92                        cfs_duration_sec(cfs_time_sub(cfs_time_current(),now)));
  93 }
  94
  95 #define CFS_RATELIMIT(seconds)                                  \
  96 ({                                                              \
  97         /*                                                      \
  98          * XXX nikita: non-portable initializer                 \
  99          */                                                     \
 100         static time_t __next_message = 0;                       \
 101         int result;                                             \
 102                                                                 \
 103         if (cfs_time_after(cfs_time_current(), __next_message)) \
 104                 result = 1;                                     \
 105         else {                                                  \
 106                 __next_message = cfs_time_shift(seconds);       \
 107                 result = 0;                                     \
 108         }                                                       \
 109         result;                                                 \
 110 })
 111
 112 /*
 113  * helper function similar to do_gettimeofday() of Linux kernel
 114  */
 115 static inline void cfs_fs_timeval(struct timeval *tv)
 116 {
 117         cfs_fs_time_t time;
 118
 119         cfs_fs_time_current(&time);
 120         cfs_fs_time_usec(&time, tv);
 121 }
 122
 123 /*
 124  * return valid time-out based on user supplied one. Currently we only check
 125  * that time-out is not shorted than allowed.
 126  */
 127 static inline cfs_duration_t cfs_timeout_cap(cfs_duration_t timeout)
 128 {
 129         if (timeout < CFS_TICK)
 130                 timeout = CFS_TICK;
 131         return timeout;
 132 }
 133
 134 #endif