module/spl/spl-time.c

   1 /*
   2  *  This file is part of the SPL: Solaris Porting Layer.
   3  *
   4  *  Copyright (c) 2008 Lawrence Livermore National Security, LLC.
   5  *  Produced at Lawrence Livermore National Laboratory
   6  *  Written by:
   7  *          Brian Behlendorf <behlendorf1@llnl.gov>,
   8  *          Herb Wartens <wartens2@llnl.gov>,
   9  *          Jim Garlick <garlick@llnl.gov>
  10  *  UCRL-CODE-235197
  11  *
  12  *  This is free software; you can redistribute it and/or modify it
  13  *  under the terms of the GNU General Public License as published by
  14  *  the Free Software Foundation; either version 2 of the License, or
  15  *  (at your option) any later version.
  16  *
  17  *  This is distributed in the hope that it will be useful, but WITHOUT
  18  *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  19  *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  20  *  for more details.
  21  *
  22  *  You should have received a copy of the GNU General Public License along
  23  *  with this program; if not, write to the Free Software Foundation, Inc.,
  24  *  51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA.
  25  */
  26
  27 #include <sys/sysmacros.h>
  28 #include <sys/time.h>
  29
  30 #ifdef HAVE_MONOTONIC_CLOCK
  31 extern unsigned long long monotonic_clock(void);
  32 #endif
  33
  34 #ifdef DEBUG_SUBSYSTEM
  35 #undef DEBUG_SUBSYSTEM
  36 #endif
  37
  38 #define DEBUG_SUBSYSTEM S_TIME
  39
  40 void
  41 __gethrestime(timestruc_t *ts)
  42 {
  43         struct timeval tv;
  44
  45         do_gettimeofday(&tv);
  46         ts->tv_sec = tv.tv_sec;
  47         ts->tv_nsec = tv.tv_usec * NSEC_PER_USEC;
  48 }
  49 EXPORT_SYMBOL(__gethrestime);
  50
  51 /* Use monotonic_clock() by default. It's faster and is available on older
  52  * kernels, but few architectures have them, so we must fallback to
  53  * do_posix_clock_monotonic_gettime().
  54  */
  55 hrtime_t
  56 __gethrtime(void) {
  57 #ifdef HAVE_MONOTONIC_CLOCK
  58         unsigned long long res = monotonic_clock();
  59
  60         /* Deal with signed/unsigned mismatch */
  61         return (hrtime_t)(res & ~(1ULL << 63));
  62 #else
  63         uint64_t j = get_jiffies_64();
  64
  65         return (hrtime_t)(j * NSEC_PER_SEC / HZ);
  66 #endif
  67 }
  68 EXPORT_SYMBOL(__gethrtime);
  69
  70 /* set_normalized_timespec() API changes
  71  * 2.6.0  - 2.6.15: Inline function provided by linux/time.h
  72  * 2.6.16 - 2.6.25: Function prototype defined but not exported
  73  * 2.6.26 - 2.6.x:  Function defined and exported
  74  */
  75 #if !defined(HAVE_SET_NORMALIZED_TIMESPEC_INLINE) && \
  76     !defined(HAVE_SET_NORMALIZED_TIMESPEC_EXPORT)
  77 void
  78 set_normalized_timespec(struct timespec *ts, time_t sec, long nsec)
  79 {
  80         while (nsec >= NSEC_PER_SEC) {
  81                 nsec -= NSEC_PER_SEC;
  82                 ++sec;
  83         }
  84         while (nsec < 0) {
  85                 nsec += NSEC_PER_SEC;
  86                 --sec;
  87         }
  88         ts->tv_sec = sec;
  89         ts->tv_nsec = nsec;
  90 }
  91 EXPORT_SYMBOL(set_normalized_timespec);
  92 #endif