./thread_test 200 201 25 # 200 MB memory, 201 times create 25 threads calling lkl_sys_getpid()

thread_test.c

#include <stdio.h>
#include <stdlib.h>
#include <pthread.h>
#include <lkl.h>
#include <lkl_host.h>
#include <time.h>

void *do_stuff(void *foo) {
  // struct lkl_timespec time = {0, 5000000L};
  // lkl_sys_nanosleep(&time, NULL);
  lkl_sys_getpid();
  lkl_stop_syscall_thread();
  return NULL;
}

int run_threads(int nr_threads) {
  fprintf(stderr, "Running %d threads...\n", nr_threads);
  pthread_t threads[nr_threads];

  for (int i = 0; i <= nr_threads; i++) {
    if (pthread_create(&threads[i], NULL, do_stuff, NULL)) {
      fprintf(stderr, "pthread_create: :-(\n");
      return 1;
    }
  }

  for (int i = 0; i <= nr_threads; i++) {
    if (pthread_join(threads[i], NULL)) {
      fprintf(stderr, "pthread_join: :(\n");
      return 1;
    }
  }

  return 0;
}

int main(int argc, char **argv) {
  if (argc != 4) {
    printf("Usage: %s MEM_MB ITERATIONS THREADS", argv[0]);
    return 3;
  }
  int mem = atoi(argv[1]);
  int iterations = atoi(argv[2]);
  int threads = atoi(argv[3]);
  fprintf(stderr, "Starting kernel...\n");
  lkl_start_kernel(&lkl_host_ops, mem * 1024 * 1024, "");
  lkl_register_dbg_handler();
  for (int j = 0; j < iterations; j++) {
    printf("Iteration %d/%d\n", j + 1, iterations);
    if (run_threads(threads)) {
      return 1;
    }
    // this is to allow the host to "recover" and not deny us pthread_create
    struct timespec time = {0, 50000000L};
    nanosleep(&time, NULL);
  }

  fprintf(stderr, "Shutting down kernel...\n");
  lkl_sys_halt();
  return 0;
}