sysdeps/generic/hp-timing.h

   1 /* High precision, low overhead timing functions.  Generic version.
   2    Copyright (C) 1998-2022 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <https://www.gnu.org/licenses/>.  */
  18
  19 #ifndef _HP_TIMING_H
  20 #define _HP_TIMING_H    1
  21
  22 #include <time.h>
  23 #include <stdint.h>
  24 #include <hp-timing-common.h>
  25
  26 /* It should not be used for ld.so.  */
  27 #define HP_TIMING_INLINE        (0)
  28
  29 typedef uint64_t hp_timing_t;
  30
  31 /* The clock_gettime (CLOCK_MONOTONIC) has unspecified starting time,
  32    nano-second accuracy, and for some architectues is implemented as
  33    vDSO symbol.  */
  34 #ifdef _ISOMAC
  35 # define HP_TIMING_NOW(var) \
  36 ({                                                              \
  37   struct timespec tv;                                           \
  38   clock_gettime (CLOCK_MONOTONIC, &tv);                         \
  39   (var) = (tv.tv_nsec + UINT64_C(1000000000) * tv.tv_sec);      \
  40 })
  41 #else
  42 # define HP_TIMING_NOW(var) \
  43 ({                                                              \
  44   struct __timespec64 tv;                                               \
  45   __clock_gettime64 (CLOCK_MONOTONIC, &tv);                     \
  46   (var) = (tv.tv_nsec + UINT64_C(1000000000) * tv.tv_sec);      \
  47 })
  48 #endif
  49
  50 #endif  /* hp-timing.h */