| C MP+unlocklockonceonce+fencermbonceonce | |
| (* | |
| * Result: Never | |
| * | |
| * If two locked critical sections execute on the same CPU, stores in the | |
| * first must propagate to each CPU before stores in the second do, even if | |
| * the critical sections are protected by different locks. | |
| *) | |
| {} | |
| P0(spinlock_t *s, spinlock_t *t, int *x, int *y) | |
| { | |
| spin_lock(s); | |
| WRITE_ONCE(*x, 1); | |
| spin_unlock(s); | |
| spin_lock(t); | |
| WRITE_ONCE(*y, 1); | |
| spin_unlock(t); | |
| } | |
| P1(int *x, int *y) | |
| { | |
| int r1; | |
| int r2; | |
| r1 = READ_ONCE(*y); | |
| smp_rmb(); | |
| r2 = READ_ONCE(*x); | |
| } | |
| exists (1:r1=1 /\ 1:r2=0) |