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| C MP+fencewmbonceonce+fencermbonceonce
|
| (*
| * Result: Never
| *
| * This litmus test demonstrates that smp_wmb() and smp_rmb() provide
| * sufficient ordering for the message-passing pattern. However, it
| * is usually better to use smp_store_release() and smp_load_acquire().
| *)
|
| {}
|
| P0(int *x, int *y)
| {
| WRITE_ONCE(*x, 1);
| smp_wmb();
| WRITE_ONCE(*y, 1);
| }
|
| P1(int *x, int *y)
| {
| int r0;
| int r1;
|
| r0 = READ_ONCE(*y);
| smp_rmb();
| r1 = READ_ONCE(*x);
| }
|
| exists (1:r0=1 /\ 1:r1=0)
|
|
