LISA Weak-RCU-Readers-With-Grace (*Paul says allowed since mid June*) { x = 0; y = 0; z = 0; } P0 | P1 | P2 ; f[rcu_read_lock] | | f[rcu_read_lock] ; r[once] r1 y | r[once] r2 x | r[once] r3 z ; | f[sync] | ; w[once] x 1 | w[once] z 1 | w[once] y 1 ; f[rcu_read_unlock] | | f[rcu_read_unlock] ; Observed 2:r3=1; 1:r2=1; 0:r1=1;