0001 C ISA2+pooncelock+pooncelock+pombonce
0002
0003 (*
0004 * Result: Never
0005 *
0006 * This test shows that write-write ordering provided by locks
0007 * (in P0() and P1()) is visible to external process P2().
0008 *)
0009
0010 {}
0011
0012 P0(int *x, int *y, spinlock_t *mylock)
0013 {
0014 spin_lock(mylock);
0015 WRITE_ONCE(*x, 1);
0016 WRITE_ONCE(*y, 1);
0017 spin_unlock(mylock);
0018 }
0019
0020 P1(int *y, int *z, spinlock_t *mylock)
0021 {
0022 int r0;
0023
0024 spin_lock(mylock);
0025 r0 = READ_ONCE(*y);
0026 WRITE_ONCE(*z, 1);
0027 spin_unlock(mylock);
0028 }
0029
0030 P2(int *x, int *z)
0031 {
0032 int r1;
0033 int r2;
0034
0035 r2 = READ_ONCE(*z);
0036 smp_mb();
0037 r1 = READ_ONCE(*x);
0038 }
0039
0040 exists (1:r0=1 /\ 2:r2=1 /\ 2:r1=0)
