C C-Andrea-Parri-After-Atomic-Fence-00 (* Sometimes, as atomic_set and atomic_read are not RMW's *) { } P0(atomic_t *u, atomic_t *v) { int r0; atomic_set(u, 1); smp_mb__after_atomic(); r0 = atomic_read(v); } P1(atomic_t *u, atomic_t *v) { int r0; atomic_set(v, 1); smp_mb__after_atomic(); r0 = atomic_read(u); } Observed 1:r0=0; 0:r0=0;