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SubjectRe: [PATCH] rcuwait: do not enter RCU protection unless a wakeup is needed
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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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