[$] The RCU API, 2024 edition

Read-copy-update (RCU) is a synchronization mechanism that was added to the
Linux kernel in October 2002. RCU is most frequently used as a replacement
for reader-writer locking, but is also used in a
number of other ways. This article covers recent changes to the RCU
API; it was contributed by Paul McKenney, Boqun Feng, Frederic Weisbecker,
Joel Fernandes, Neeraj Upadhyay, and Uladzislau Rezki.