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| C ISA2+pooncelock+pooncelock+pombonce
|
| (*
| * Result: Sometimes
| *
| * This test shows that the ordering provided by a lock-protected S
| * litmus test (P0() and P1()) are not visible to external process P2().
| * This is likely to change soon.
| *)
|
| {}
|
| P0(int *x, int *y, spinlock_t *mylock)
| {
| spin_lock(mylock);
| WRITE_ONCE(*x, 1);
| WRITE_ONCE(*y, 1);
| spin_unlock(mylock);
| }
|
| P1(int *y, int *z, spinlock_t *mylock)
| {
| int r0;
|
| spin_lock(mylock);
| r0 = READ_ONCE(*y);
| WRITE_ONCE(*z, 1);
| spin_unlock(mylock);
| }
|
| P2(int *x, int *z)
| {
| int r1;
| int r2;
|
| r2 = READ_ONCE(*z);
| smp_mb();
| r1 = READ_ONCE(*x);
| }
|
| exists (1:r0=1 /\ 2:r2=1 /\ 2:r1=0)
|
|
