On Sun, Sep 18, 2022 at 10:12:31PM +0000, Joel Fernandes (Google) wrote: > When going through the lazy-rcu work, I noticed that > rcu_barrier_entrain() does not really wake up the rcuog GP thread in any > path after entraining. This means it is possible the GP thread is not > awakened soon (say there were no CBs in the cblist after entraining > time). Right. > > Further, nothing appears to be calling the rcu_barrier callback > directly in the case the ->cblist was empty which means if the IPI gets > delayed enough to make the ->cblist empty and it turns out to be the last > CPU holding, then nothing calls completes rcu_state.barrier_completion. No need for that, if the cblist is empty there is no need for a callback to enqueue. Thanks.
