User: Password:
Subscribe / Log in / New account

Reader-to-updater upgrade?

Reader-to-updater upgrade?

Posted Jan 10, 2008 21:02 UTC (Thu) by PaulMcKenney (subscriber, #9624)
In reply to: Reader-to-updater upgrade? by jarkao2
Parent article: What is RCU? Part 2: Usage

1. Indeed, the upgrade-to-update change would be visible to the remainder of the RCU read-side
critical section.  However, in a surprisingly large number of cases, there is no need for
additional verification steps (though verification can be used when needed).  This is a key
difference between RCU and non-blocking synchronization (NBS) -- NBS would absolutely require
the validation steps in order to avoid memory corruption.

2. Good point -- although rcu_assign_pointer(head, NULL) is superfluous, it is good practice,
and there is no performance penalty.

3. Good eyes!!!

(Log in to post comments)

Copyright © 2017, Eklektix, Inc.
Comments and public postings are copyrighted by their creators.
Linux is a registered trademark of Linus Torvalds