LISA auto/RW-Rs+RW-RD+RW-R+RW-R
(*
* Result: Sometimes
*
* Process 0 starts (t=297995).
*
* P0 advances slightly (t=297996).
*
* P1 advances slightly (t=297998).
*
* P2 goes back a bit less than one grace period (t=198999).
*
* P3 goes back a bit less than one grace period (t=100000).
*
* Process 0 start at t=297995, process 4 end at t=100000: Cycle allowed.
*)
{
0:r3=x2; x1=y2; 1:r4=y2;
}
P0 | P1 | P2 | P3 ;
f[rcu_read_lock] | f[rcu_read_lock] | f[rcu_read_lock] | f[rcu_read_lock] ;
r[once] r1 x0 | r[deref] r1 x1 | r[once] r1 x2 | r[once] r1 x3 ;
w[assign] x1 r3 | w[once] r1 1 | w[once] x3 1 | w[once] x0 1 ;
f[rcu_read_unlock] | f[rcu_read_unlock] | f[rcu_read_unlock] | f[rcu_read_unlock] ;
Observed
3:r1=1; 2:r1=1; 1:r1=x2; 0:r1=1;