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C ISA2+pooncelock+pooncelock+pombonce
(*
* Result: Never
*
* This test shows that write-write ordering provided by locks
* (in P0() and P1()) is visible to external process P2().
*)
{
spinlock_t mylock;
int x;
int y;
int z;
}
P0(int *x, int *y, spinlock_t *mylock)
{
spin_lock(mylock);
WRITE_ONCE(*x, 1);
WRITE_ONCE(*y, 1);
spin_unlock(mylock);
}
P1(int *y, int *z, spinlock_t *mylock)
{
int r0;
spin_lock(mylock);
r0 = READ_ONCE(*y);
WRITE_ONCE(*z, 1);
spin_unlock(mylock);
}
P2(int *x, int *z)
{
int r1;
int r2;
r2 = READ_ONCE(*z);
smp_mb();
r1 = READ_ONCE(*x);
}
exists (1:r0=1 /\ 2:r2=1 /\ 2:r1=0)
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