linuxdebug/Documentation/litmus-tests/atomic/Atomic-RMW+mb__after_atomic...

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C Atomic-RMW+mb__after_atomic-is-stronger-than-acquire
(*
* Result: Never
*
* Test that an atomic RMW followed by a smp_mb__after_atomic() is
* stronger than a normal acquire: both the read and write parts of
* the RMW are ordered before the subsequential memory accesses.
*)
{
}
P0(int *x, atomic_t *y)
{
int r0;
int r1;
r0 = READ_ONCE(*x);
smp_rmb();
r1 = atomic_read(y);
}
P1(int *x, atomic_t *y)
{
atomic_inc(y);
smp_mb__after_atomic();
WRITE_ONCE(*x, 1);
}
exists
(0:r0=1 /\ 0:r1=0)