tests/benchmark/bench.c

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