CPU 1 CPU 2
=============== ===============
- { A == 1, B == 2, C = 3, P == &A, Q == &C }
+ { A == 1, B == 2, C == 3, P == &A, Q == &C }
B = 4; Q = P;
P = &B D = *Q;
CPU 1 CPU 2
=============== ===============
- { A == 1, B == 2, C = 3, P == &A, Q == &C }
+ { A == 1, B == 2, C == 3, P == &A, Q == &C }
B = 4;
<write barrier>
WRITE_ONCE(P, &B)
CPU 1 CPU 2
=============== ===============
- { A == 1, B == 2, C = 3, P == &A, Q == &C }
+ { A == 1, B == 2, C == 3, P == &A, Q == &C }
B = 4;
<write barrier>
WRITE_ONCE(P, &B);
See the subsection on "Cache Coherency" above.
VIRTUAL MACHINE GUESTS
--------------------
+----------------------
Guests running within virtual machines might be affected by SMP effects even if
the guest itself is compiled without SMP support. This is an artifact of