0bd55c6936
Historically, no-CBs CPUs allowed the scheduler-clock tick to be unconditionally disabled on any transition to idle or nohz_full userspace execution (see the rcu_needs_cpu() implementations). Unfortunately, the checks used by rcu_needs_cpu() are defeated now that no-CBs CPUs use ->cblist, which might make users of battery-powered devices rather unhappy. This commit therefore adds explicit rcu_segcblist_is_offloaded() checks to return to the historical energy-efficient semantics. Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>