tests/benchmark/bench.c

   1 /*
   2  * bench.c
   3  *
   4  * LTTng Userspace Tracer (UST) - benchmark tool
   5  *
   6  * Copyright 2010 - Douglas Santos <douglas.santos@polymtl.ca>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License along
  19  * with this program; if not, write to the Free Software Foundation, Inc.,
  20  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  21  */
  22
  23 #define _GNU_SOURCE
  24 #include <stdio.h>
  25 #include <pthread.h>
  26 #include <stdlib.h>
  27 #include <unistd.h>
  28 #include <sched.h>
  29 #include <ust/marker.h>
  30 #include <time.h>
  31
  32 static int nr_cpus;
  33 static unsigned long nr_events;
  34
  35 void do_stuff(void)
  36 {
  37         int v;
  38         FILE *file;
  39
  40         v = 1;
  41
  42         file = fopen("/dev/null", "a");
  43         fprintf(file, "%d", v);
  44         fclose(file);
  45         time(NULL);
  46
  47 #ifdef MARKER
  48         ust_marker(event, "event %d", v);
  49 #endif
  50
  51 }
  52
  53
  54 void *function(void *arg)
  55 {
  56         unsigned long i;
  57
  58         for(i = 0; i < nr_events; i++) {
  59                 do_stuff();
  60         }
  61         return NULL;
  62 }
  63
  64 void usage(char **argv) {
  65         printf("Usage: %s nr_cpus nr_events\n", argv[0]);
  66 }
  67
  68
  69 int main(int argc, char **argv)
  70 {
  71         void *retval;
  72         int i;
  73
  74         if (argc < 3) {
  75                 usage(argv);
  76                 exit(1);
  77         }
  78
  79         nr_cpus = atoi(argv[1]);
  80         printf("using %d processor(s)\n", nr_cpus);
  81
  82         nr_events = atol(argv[2]);
  83         printf("using %ld events per cpu\n", nr_events);
  84
  85         pthread_t thread[nr_cpus];
  86         for (i = 0; i < nr_cpus; i++) {
  87                 if (pthread_create(&thread[i], NULL, function, NULL)) {
  88                         fprintf(stderr, "thread create %d failed\n", i);
  89                         exit(1);
  90                 }
  91         }
  92
  93         for (i = 0; i < nr_cpus; i++) {
  94                 if (pthread_join(thread[i], &retval)) {
  95                         fprintf(stderr, "thread join %d failed\n", i);
  96                         exit(1);
  97                 }
  98         }
  99         return 0;
 100 }