linuxrwlocks/testcase3.c

   1 #include <stdio.h>
   2 #include <threads.h>
   3 #include <stdatomic.h>
   4
   5 #include "librace.h"
   6 #include "linuxrwlocks.h"
   7
   8 rwlock_t mylock;
   9 int shareddata;
  10
  11 atomic_int x, y;
  12
  13 static void a(void *obj)
  14 {
  15         write_lock(&mylock);
  16         atomic_store_explicit(&x, 17, memory_order_relaxed);
  17         write_unlock(&mylock);
  18
  19         if (!read_can_lock(&mylock))
  20                 return;
  21         if (read_trylock(&mylock)) {
  22                 atomic_load_explicit(&x, memory_order_relaxed);
  23                 read_unlock(&mylock);
  24         }
  25 }
  26
  27 static void b(void *obj)
  28 {
  29
  30         if (write_trylock(&mylock)) {
  31                 atomic_store_explicit(&x, 16, memory_order_relaxed);
  32                 write_unlock(&mylock);
  33         }
  34
  35         read_lock(&mylock);
  36         atomic_load_explicit(&x, memory_order_relaxed);
  37         read_unlock(&mylock);
  38 }
  39
  40 int user_main(int argc, char **argv)
  41 {
  42         thrd_t t1, t2;
  43         /** @Entry */
  44         atomic_init(&mylock.lock, RW_LOCK_BIAS);
  45         atomic_init(&x, 0);
  46         atomic_init(&y, 0);
  47
  48         thrd_create(&t1, (thrd_start_t)&a, NULL);
  49         thrd_create(&t2, (thrd_start_t)&b, NULL);
  50
  51         thrd_join(t1);
  52         thrd_join(t2);
  53
  54         return 0;
  55 }