tests/bench.h

   1 /* Utilities for benchmarks.
   2    Copyright (C) 2018-2025 Free Software Foundation, Inc.
   3
   4    This program is free software: you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation, either version 3 of the License, or
   7    (at your option) any later version.
   8
   9    This program is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
  16
  17 #include <stdio.h>
  18 #include <sys/resource.h>
  19 #include <sys/time.h>
  20
  21 struct timings_state
  22 {
  23   /* Filled when the timings start.  */
  24   struct timeval real_start;
  25   struct timeval user_start;
  26   struct timeval sys_start;
  27   /* Filled when the timings end.  */
  28   long real_usec;
  29   long user_usec;
  30   long sys_usec;
  31 };
  32
  33 static void
  34 timing_start (struct timings_state *ts)
  35 {
  36   struct rusage usage;
  37
  38   getrusage (RUSAGE_SELF, &usage);
  39   ts->user_start = usage.ru_utime;
  40   ts->sys_start = usage.ru_stime;
  41
  42   gettimeofday (&ts->real_start, NULL);
  43 }
  44
  45 static void
  46 timing_end (struct timings_state *ts)
  47 {
  48   struct timeval real_end;
  49   struct rusage usage;
  50
  51   gettimeofday (&real_end, NULL);
  52
  53   getrusage (RUSAGE_SELF, &usage);
  54
  55   ts->real_usec = (real_end.tv_sec - ts->real_start.tv_sec) * 1000000
  56                   + real_end.tv_usec - ts->real_start.tv_usec;
  57   ts->user_usec = (usage.ru_utime.tv_sec - ts->user_start.tv_sec) * 1000000
  58                   + usage.ru_utime.tv_usec - ts->user_start.tv_usec;
  59   ts->sys_usec = (usage.ru_stime.tv_sec - ts->sys_start.tv_sec) * 1000000
  60                  + usage.ru_stime.tv_usec - ts->sys_start.tv_usec;
  61 }
  62
  63 _GL_UNUSED static void
  64 timing_output (const struct timings_state *ts)
  65 {
  66   printf ("real %10.6f\n", (double)ts->real_usec / 1000000.0);
  67   printf ("user %7.3f\n", (double)ts->user_usec / 1000000.0);
  68   printf ("sys  %7.3f\n", (double)ts->sys_usec / 1000000.0);
  69 }