Author: Nicholas Mc Guire <hofrat@osadl.org> rcu_cpu_has_callbacks() is declared int. The current declaration was introduced in commit c0f4dfd4f90f (rcu: Make RCU_FAST_NO_HZ take advantage of numbered callbacks). But it is actually returning bool and as the function description states » * Return true if the specified CPU has any callback…. », this probably should be a bool as …