documentation: Explain why rcu_read_lock() needs no barrier()
authorPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Tue, 16 Feb 2016 01:29:47 +0000 (17:29 -0800)
committerPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Thu, 31 Mar 2016 20:33:20 +0000 (13:33 -0700)
commitd8936c0b7e29510ce8f5c85ff5fcc592a938e860
tree013f527bbb3972263e4428eb5b9e3dc762c76c92
parentf43b62542eb61a52d97d6b82a786a912fa5e6c51
documentation: Explain why rcu_read_lock() needs no barrier()

This commit adds a Quick Quiz whose answer explains why the compiler
code reordering enabled by CONFIG_PREEMPT=n's empty rcu_read_lock()
and rcu_read_unlock() functions does not hinder RCU's ability to figure
out which RCU read-side critical sections have completed and not.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Documentation/RCU/Design/Requirements/Requirements.html
Documentation/RCU/Design/Requirements/Requirements.htmlx