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| C IRIW+fencembonceonces+OnceOnce
|
| (*
| * Result: Never
| *
| * Test of independent reads from independent writes with smp_mb()
| * between each pairs of reads. In other words, is smp_mb() sufficient to
| * cause two different reading processes to agree on the order of a pair
| * of writes, where each write is to a different variable by a different
| * process? This litmus test exercises LKMM's "propagation" rule.
| *)
|
| {}
|
| P0(int *x)
| {
| WRITE_ONCE(*x, 1);
| }
|
| P1(int *x, int *y)
| {
| int r0;
| int r1;
|
| r0 = READ_ONCE(*x);
| smp_mb();
| r1 = READ_ONCE(*y);
| }
|
| P2(int *y)
| {
| WRITE_ONCE(*y, 1);
| }
|
| P3(int *x, int *y)
| {
| int r0;
| int r1;
|
| r0 = READ_ONCE(*y);
| smp_mb();
| r1 = READ_ONCE(*x);
| }
|
| exists (1:r0=1 /\ 1:r1=0 /\ 3:r0=1 /\ 3:r1=0)
|
|
