test/tsan/bench.h

   1 #include <pthread.h>
   2 #include <stdlib.h>
   3 #include <stddef.h>
   4 #include <unistd.h>
   5 #include <stdio.h>
   6 #include <time.h>
   7
   8 int bench_nthread;
   9 int bench_niter;
  10 int grow_clock_var;
  11 pthread_barrier_t glow_clock_barrier;
  12
  13 void bench();  // defined by user
  14 void start_thread_group(int nth, void(*f)(int tid));
  15 void grow_clock_worker(int tid);
  16
  17 int main(int argc, char **argv) {
  18   bench_nthread = 2;
  19   if (argc > 1)
  20     bench_nthread = atoi(argv[1]);
  21   bench_niter = 100;
  22   if (argc > 2)
  23     bench_niter = atoi(argv[2]);
  24
  25   // Grow thread's clock.
  26   int clock_size = 10;
  27   if (argc > 1)
  28     clock_size = 1000;
  29   pthread_barrier_init(&glow_clock_barrier, 0, clock_size);
  30   start_thread_group(clock_size, grow_clock_worker);
  31   pthread_barrier_destroy(&glow_clock_barrier);
  32   __atomic_load_n(&grow_clock_var, __ATOMIC_ACQUIRE);
  33
  34   timespec tp0;
  35   clock_gettime(CLOCK_MONOTONIC, &tp0);
  36   bench();
  37   timespec tp1;
  38   clock_gettime(CLOCK_MONOTONIC, &tp1);
  39   unsigned long long t =
  40       (tp1.tv_sec * 1000000000ULL + tp1.tv_nsec) -
  41       (tp0.tv_sec * 1000000000ULL + tp0.tv_nsec);
  42   fprintf(stderr, "%llu ns/iter\n", t / bench_niter);
  43   fprintf(stderr, "DONE\n");
  44 }
  45
  46 void start_thread_group(int nth, void(*f)(int tid)) {
  47   pthread_t *th = (pthread_t*)malloc(nth * sizeof(pthread_t));
  48   for (int i = 0; i < nth; i++)
  49     pthread_create(&th[i], 0, (void*(*)(void*))f, (void*)(long)i);
  50   for (int i = 0; i < nth; i++)
  51     pthread_join(th[i], 0);
  52 }
  53
  54 void grow_clock_worker(int tid) {
  55   int res = pthread_barrier_wait(&glow_clock_barrier);
  56   if (res == PTHREAD_BARRIER_SERIAL_THREAD)
  57     __atomic_store_n(&grow_clock_var, 0, __ATOMIC_RELEASE);
  58 }
  59