Messages in this thread | | | Date | Wed, 20 Oct 2021 13:37:54 +0200 | Subject | Re: [PATCH] rcuwait: do not enter RCU protection unless a wakeup is needed | From | Paolo Bonzini <> |
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On 20/10/21 13:17, Peter Zijlstra wrote: > AFAICT, rcu_read_lock() for PREEMPT_RCU is: > > WRITE_ONCE(current->rcu_read_lock_nesting, READ_ONCE(current->rcu_read_lock_nesting) + 1); > barrier();
rcu_read_unlock() is the expensive one if you need to go down rcu_read_unlock_special().
Paolo
> Paul?
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