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
  15 static int nr_cpus;
  16 static unsigned long nr_events;
  17 pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
  18
  19 void do_stuff(void)
  20 {
  21         int v;
  22         FILE *file;
  23         int lock;
  24
  25         v = 1;
  26
  27         lock = pthread_mutex_lock(&mutex);
  28         file = fopen("/tmp/bench.txt", "a");
  29         fprintf(file, "%d", v);
  30         fclose(file);
  31         lock = pthread_mutex_unlock(&mutex);
  32
  33 #ifdef MARKER
  34         trace_mark(ust, event, "event %d", v);
  35 #endif
  36
  37 }
  38
  39
  40 void *function(void *arg)
  41 {
  42         unsigned long i;
  43
  44         for(i = 0; i < nr_events; i++) {
  45                 do_stuff();
  46         }
  47         return NULL;
  48 }
  49
  50
  51 void usage(char **argv) {
  52         printf("Usage: %s nr_cpus nr_events\n", argv[0]);
  53 }
  54
  55
  56 int main(int argc, char **argv)
  57 {
  58         void *retval;
  59         int i;
  60
  61         if (argc < 3) {
  62                 usage(argv);
  63                 exit(1);
  64         }
  65
  66         nr_cpus = atoi(argv[1]);
  67         printf("using %d processor(s)\n", nr_cpus);
  68
  69         nr_events = atol(argv[2]);
  70         printf("using %ld events per cpu\n", nr_events);
  71
  72         pthread_t thread[nr_cpus];
  73         for (i = 0; i < nr_cpus; i++) {
  74                 if (pthread_create(&thread[i], NULL, function, NULL)) {
  75                         fprintf(stderr, "thread create %d failed\n", i);
  76                         exit(1);
  77                 }
  78         }
  79
  80         for (i = 0; i < nr_cpus; i++) {
  81                 if (pthread_join(thread[i], &retval)) {
  82                         fprintf(stderr, "thread join %d failed\n", i);
  83                         exit(1);
  84                 }
  85         }
  86         return 0;
  87 }