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| C Z6.0+pooncelock+poonceLock+pombonce
|
| (*
| * Result: Never
| *
| * This litmus test demonstrates how smp_mb__after_spinlock() may be
| * used to ensure that accesses in different critical sections for a
| * given lock running on different CPUs are nevertheless seen in order
| * by CPUs not holding that lock.
| *)
|
| {}
|
| 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);
| smp_mb__after_spinlock();
| r0 = READ_ONCE(*y);
| WRITE_ONCE(*z, 1);
| spin_unlock(mylock);
| }
|
| P2(int *x, int *z)
| {
| int r1;
|
| WRITE_ONCE(*z, 2);
| smp_mb();
| r1 = READ_ONCE(*x);
| }
|
| exists (1:r0=1 /\ z=2 /\ 2:r1=0)
|
|
