sys/sys/microtime_pcpu.h

   1 /*
   2  * Copyright (c) 2014 The DragonFly Project.  All rights reserved.
   3  *
   4  * This code is derived from software contributed to The DragonFly Project
   5  * by Sepherosa Ziehau <sepherosa@gmail.com>
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  *
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in
  15  *    the documentation and/or other materials provided with the
  16  *    distribution.
  17  * 3. Neither the name of The DragonFly Project nor the names of its
  18  *    contributors may be used to endorse or promote products derived
  19  *    from this software without specific, prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  24  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
  25  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  26  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
  27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  */
  34
  35 #ifndef _SYS_MICROTIME_PCPU_H_
  36 #define _SYS_MICROTIME_PCPU_H_
  37
  38 #ifndef _SYS_PARAM_H_
  39 #include <sys/param.h>
  40 #endif
  41
  42 #ifndef _SYS_TIME_H_
  43 #include <sys/time.h>
  44 #endif
  45
  46 #include <machine/clock.h>
  47 #include <machine/cpufunc.h>
  48
  49 /*
  50  * This 'time' only guarantees monotonicly increment on the same CPU
  51  */
  52
  53 union microtime_pcpu {
  54         struct timeval  tv;
  55         uint64_t        tsc;
  56 };
  57
  58 static __inline void
  59 microtime_pcpu_get(union microtime_pcpu *t)
  60 {
  61         if (tsc_invariant)
  62                 t->tsc = rdtsc();
  63         else
  64                 microuptime(&t->tv);
  65 }
  66
  67 static __inline int
  68 microtime_pcpu_diff(const union microtime_pcpu *s,
  69     const union microtime_pcpu *e)
  70 {
  71         if (tsc_invariant) {
  72                 return (((e->tsc - s->tsc) * 1000000) / tsc_frequency);
  73         } else {
  74                 return ((e->tv.tv_usec - s->tv.tv_usec) +
  75                         (e->tv.tv_sec - s->tv.tv_sec) * 1000000);
  76         }
  77 }
  78
  79 #endif  /* !_SYS_MICROTIME_PCPU_H_ */