1C cmpxchg-fail-ordered-1 2 3(* 4 * Result: Never 5 * 6 * Demonstrate that a failing cmpxchg() operation will act as a full 7 * barrier when followed by smp_mb__after_atomic(). 8 *) 9 10{} 11 12P0(int *x, int *y, int *z) 13{ 14 int r0; 15 int r1; 16 17 WRITE_ONCE(*x, 1); 18 r1 = cmpxchg(z, 1, 0); 19 smp_mb__after_atomic(); 20 r0 = READ_ONCE(*y); 21} 22 23P1(int *x, int *y, int *z) 24{ 25 int r0; 26 int r1; 27 28 WRITE_ONCE(*y, 1); 29 r1 = cmpxchg(z, 1, 0); 30 smp_mb__after_atomic(); 31 r0 = READ_ONCE(*x); 32} 33 34locations[0:r1;1:r1] 35exists (0:r0=0 /\ 1:r0=0) 36