kernel/drivers/staging/lustre/include/linux/libcfs/libcfs_time.h

   1 /*
   2  * GPL HEADER START
   3  *
   4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 only,
   8  * as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * General Public License version 2 for more details (a copy is included
  14  * in the LICENSE file that accompanied this code).
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * version 2 along with this program; If not, see
  18  * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
  19  *
  20  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  21  * CA 95054 USA or visit www.sun.com if you need additional information or
  22  * have any questions.
  23  *
  24  * GPL HEADER END
  25  */
  26 /*
  27  * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
  28  * Use is subject to license terms.
  29  */
  30 /*
  31  * This file is part of Lustre, http://www.lustre.org/
  32  * Lustre is a trademark of Sun Microsystems, Inc.
  33  *
  34  * libcfs/include/libcfs/libcfs_time.h
  35  *
  36  * Time functions.
  37  *
  38  */
  39
  40 #ifndef __LIBCFS_TIME_H__
  41 #define __LIBCFS_TIME_H__
  42 /*
  43  * generic time manipulation functions.
  44  */
  45
  46 static inline unsigned long cfs_time_add(unsigned long t, long d)
  47 {
  48         return (unsigned long)(t + d);
  49 }
  50
  51 static inline unsigned long cfs_time_sub(unsigned long t1, unsigned long t2)
  52 {
  53         return (unsigned long)(t1 - t2);
  54 }
  55
  56 static inline int cfs_time_after(unsigned long t1, unsigned long t2)
  57 {
  58         return time_before(t2, t1);
  59 }
  60
  61 static inline int cfs_time_aftereq(unsigned long t1, unsigned long t2)
  62 {
  63         return time_before_eq(t2, t1);
  64 }
  65
  66 static inline unsigned long cfs_time_shift(int seconds)
  67 {
  68         return cfs_time_add(cfs_time_current(), cfs_time_seconds(seconds));
  69 }
  70
  71 static inline long cfs_timeval_sub(struct timeval *large, struct timeval *small,
  72                                    struct timeval *result)
  73 {
  74         long r = (long)(
  75                 (large->tv_sec - small->tv_sec) * ONE_MILLION +
  76                 (large->tv_usec - small->tv_usec));
  77         if (result != NULL) {
  78                 result->tv_usec = r % ONE_MILLION;
  79                 result->tv_sec = r / ONE_MILLION;
  80         }
  81         return r;
  82 }
  83
  84 static inline void cfs_slow_warning(unsigned long now, int seconds, char *msg)
  85 {
  86         if (cfs_time_after(cfs_time_current(),
  87                            cfs_time_add(now, cfs_time_seconds(15))))
  88                 CERROR("slow %s "CFS_TIME_T" sec\n", msg,
  89                        cfs_duration_sec(cfs_time_sub(cfs_time_current(), now)));
  90 }
  91
  92 #define CFS_RATELIMIT(seconds)                            \
  93 ({                                                            \
  94         /*                                                    \
  95          * XXX nikita: non-portable initializer          \
  96          */                                                  \
  97         static time_t __next_message;                  \
  98         int result;                                          \
  99                                                                 \
 100         if (cfs_time_after(cfs_time_current(), __next_message)) \
 101                 result = 1;                                  \
 102         else {                                            \
 103                 __next_message = cfs_time_shift(seconds);       \
 104                 result = 0;                                  \
 105         }                                                      \
 106         result;                                          \
 107 })
 108
 109 /*
 110  * helper function similar to do_gettimeofday() of Linux kernel
 111  */
 112 static inline void cfs_fs_timeval(struct timeval *tv)
 113 {
 114         struct timespec time;
 115
 116         cfs_fs_time_current(&time);
 117         cfs_fs_time_usec(&time, tv);
 118 }
 119
 120 /*
 121  * return valid time-out based on user supplied one. Currently we only check
 122  * that time-out is not shorted than allowed.
 123  */
 124 static inline long cfs_timeout_cap(long timeout)
 125 {
 126         if (timeout < CFS_TICK)
 127                 timeout = CFS_TICK;
 128         return timeout;
 129 }
 130
 131 #endif