tests/benchmark/bench.c

   1 /*
   2  * SPDX-License-Identifier: GPL-2.0-or-later
   3  *
   4  * Copyright 2010 Douglas Santos <douglas.santos@polymtl.ca>
   5  *
   6  * LTTng Userspace Tracer (UST) - benchmark tool
   7  */
   8
   9 #include <stdio.h>
  10 #include <pthread.h>
  11 #include <stdlib.h>
  12 #include <unistd.h>
  13 #include <sched.h>
  14 #include <time.h>
  15
  16 #ifdef TRACING
  17 #define TRACEPOINT_DEFINE
  18 #include "ust_tests_benchmark.h"
  19 #endif
  20
  21 static int nr_cpus;
  22 static unsigned long nr_events;
  23
  24 void do_stuff(void)
  25 {
  26         int v;
  27         FILE *file;
  28
  29         v = 1;
  30
  31         file = fopen("/dev/null", "a");
  32         fprintf(file, "%d", v);
  33         fclose(file);
  34         time(NULL);
  35
  36 #ifdef TRACING
  37         tracepoint(ust_tests_benchmark, tpbench, v);
  38 #endif
  39
  40 }
  41
  42
  43 void *function(void *arg)
  44 {
  45         unsigned long i;
  46
  47         for(i = 0; i < nr_events; i++) {
  48                 do_stuff();
  49         }
  50         return NULL;
  51 }
  52
  53 void usage(char **argv) {
  54         printf("Usage: %s nr_cpus nr_events\n", argv[0]);
  55 }
  56
  57
  58 int main(int argc, char **argv)
  59 {
  60         void *retval;
  61         int i;
  62
  63         if (argc < 3) {
  64                 usage(argv);
  65                 exit(1);
  66         }
  67
  68         nr_cpus = atoi(argv[1]);
  69         printf("using %d processor(s)\n", nr_cpus);
  70
  71         nr_events = atol(argv[2]);
  72         printf("using %ld events per cpu\n", nr_events);
  73
  74         pthread_t thread[nr_cpus];
  75         for (i = 0; i < nr_cpus; i++) {
  76                 if (pthread_create(&thread[i], NULL, function, NULL)) {
  77                         fprintf(stderr, "thread create %d failed\n", i);
  78                         exit(1);
  79                 }
  80         }
  81
  82         for (i = 0; i < nr_cpus; i++) {
  83                 if (pthread_join(thread[i], &retval)) {
  84                         fprintf(stderr, "thread join %d failed\n", i);
  85                         exit(1);
  86                 }
  87         }
  88         return 0;
  89 }