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> > > - goto out; > > > - } > > > - > > > - rcu_read_lock(); > > > + guard(rcu)(); > > > > and since this is only called from: > > > > sched_tick() /* IRQs disabled */ > > sched_balance_trigger() > > nohz_balancer_kick() > > > > with IRQs disabled, we can get rid of that rcu_read_lock() entirely. > > Then we need to add a lockdep_assert_irqs_disabled() here too. Yeah, initially I suggested to add a lockdep_assert_irqs_disabled() in nohz_balancer_kick() but what we care about here is RCU safety, if we do something unsafe in the future we should be able to catch that with rcu_dererference_all(), as pointed by Peter, right? Thanks, -Andrea