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McKenney wrote: >> On Tue, Jul 08, 2025 at 10:22:21AM -0400, Joel Fernandes wrote: >>> The check for irqs_were_disabled is redundant in >>> rcu_unlock_needs_exp_handling() as the caller already checks for this. >>> This includes the boost case as well. Just remove the redundant check. >> >> But in the very last "if" statement in the context of the last hunk of >> this patch, isn't it instead checking for !irqs_were_disabled? >> >> Or is there something that I am missing that makes this work out OK? > > You are right, after going over all the cases I introduced a behavioral change. > > Say, irqs_were_disabled was false. And say we are RCU-boosted. needs_exp might > return true now, but previously it was returning false. Further say, we are not > in hardirq. > > New code will raise softirq, old code would go to the ELSE and just set: > set_tsk_need_resched(current); > set_preempt_need_resched(); > > But preempt_bh_were_disabled that's why we're here. > > So we need to only set resched and not raise softirq, because the preempt enable > would reschedule. > > Sorry I missed this, but unless this behavior is correct or needs further work, > lets drop this patch. Thanks and kudos on the catch! Btw, Neeraj, the related patch 3/7 should still be good for applying (which has Paul's Review tag). Thanks.