- it is illegal to block or where update-side performance is
- critically important.
-
- However, the call_rcu() API should not be used lightly, as use
- of the synchronize_rcu() API generally results in simpler code.
- In addition, the synchronize_rcu() API has the nice property
- of automatically limiting update rate should grace periods
- be delayed. This property results in system resilience in face
- of denial-of-service attacks. Code using call_rcu() should limit
- update rate in order to gain this same sort of resilience. See
- checklist.txt for some approaches to limiting the update rate.