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SubjectRe: [PATCH] docs: rcu: Make reader aware of rcu_dereference_protected
On Tue, Oct 09, 2018 at 08:09:06PM -0700, Paul E. McKenney wrote:
> On Mon, Oct 08, 2018 at 06:33:41PM -0700, Joel Fernandes (Google) wrote:
> > whatisRCU says rcu_dereference cannot be used outside of rcu read lock
> > protected sections. Its better to mention rcu_dereference_protected when
> > it says that, so that the new reader is aware of this API and is not led
> > to believing that all RCU dereferences in all situations have to be
> > protected by a rcu_read_lock() and rcu_read_unlock().
> >
> > Cc: tytso@mit.edu
> > Suggested-by: tytso@mit.edu
> > Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
>
> Good stuff! I queued and pushed this with some wordsmithing. Could
> you please check for my having messed something up?

One small nit which the below diff should fix, but otherwise looks good to
me, thanks!

- Joel

----8<----

diff --git a/Documentation/RCU/whatisRCU.txt b/Documentation/RCU/whatisRCU.txt
index 38044c978e54..093b85ad49eb 100644
--- a/Documentation/RCU/whatisRCU.txt
+++ b/Documentation/RCU/whatisRCU.txt
@@ -297,7 +297,7 @@ rcu_dereference()
protected by locks acquired by the update-side code. This variant
avoids the lockdep warning that would happen when using (for
example) rcu_dereference() without rcu_read_lock() protection.
- Using rcu_dereference_protected() also have the advantage
+ Using rcu_dereference_protected() also has the advantage
of permitting compiler optimizations that rcu_dereference()
must prohibit. The rcu_dereference_protected() variant takes
a lockdep expression to indicate which locks must be acquired
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