xref: /OK3568_Linux_fs/kernel/tools/memory-model/litmus-tests/S+fencewmbonceonce+poacquireonce.litmus (revision 4882a59341e53eb6f0b4789bf948001014eff981) 
1*4882a593SmuzhiyunC S+fencewmbonceonce+poacquireonce
2*4882a593Smuzhiyun
3*4882a593Smuzhiyun(*
4*4882a593Smuzhiyun * Result: Never
5*4882a593Smuzhiyun *
6*4882a593Smuzhiyun * Can a smp_wmb(), instead of a release, and an acquire order a prior
7*4882a593Smuzhiyun * store against a subsequent store?
8*4882a593Smuzhiyun *)
9*4882a593Smuzhiyun
10*4882a593Smuzhiyun{}
11*4882a593Smuzhiyun
12*4882a593SmuzhiyunP0(int *x, int *y)
13*4882a593Smuzhiyun{
14*4882a593Smuzhiyun	WRITE_ONCE(*x, 2);
15*4882a593Smuzhiyun	smp_wmb();
16*4882a593Smuzhiyun	WRITE_ONCE(*y, 1);
17*4882a593Smuzhiyun}
18*4882a593Smuzhiyun
19*4882a593SmuzhiyunP1(int *x, int *y)
20*4882a593Smuzhiyun{
21*4882a593Smuzhiyun	int r0;
22*4882a593Smuzhiyun
23*4882a593Smuzhiyun	r0 = smp_load_acquire(y);
24*4882a593Smuzhiyun	WRITE_ONCE(*x, 1);
25*4882a593Smuzhiyun}
26*4882a593Smuzhiyun
27*4882a593Smuzhiyunexists (x=2 /\ 1:r0=1)
28