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In this configuration cond_resched() is an empty stub and > does not provide quiescent states via rcu_all_qs(). PREEMPT_RCU=y > provides this information via rcu_read_unlock() and its nesting counter. > >> So, use the availability of preempt_count() to report quiescent states >> in rcu_flavor_sched_clock_irq(). > > Okay. You might also want to update the cond_resched() comment, > s@In preemptible kernels, ->rcu_read_lock_nesting@ > In PREEMPT_RCU kernels, ->rcu_read_lock_nesting@ Good point. Will add. > Reviewed-by: Sebastian Andrzej Siewior Thanks! Ankur >> Suggested-by: Paul E. McKenney >> Signed-off-by: Ankur Arora > > Sebastian -- ankur