Commit-ID: 27566139b6e2f6cfe273e8bb0e538d7616c2ea00 Gitweb: http://git.kernel.org/tip/27566139b6e2f6cfe273e8bb0e538d7616c2ea00 Author: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx> AuthorDate: Sat, 1 Aug 2015 10:45:26 -0700 Committer: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx> CommitDate: Tue, 6 Oct 2015 11:22:28 -0700 documentation: No acquire/release for RCU readers Documentation/memory-barriers.txt calls out RCU as one of the sets of primitives associated with ACQUIRE and RELEASE. There really is an association in that rcu_assign_pointer() includes a RELEASE operation, but a quick read can convince people that rcu_read_lock() and rcu_read_unlock() have ACQUIRE and RELEASE semantics, which they do not. This commit therefore removes RCU from this list in order to avoid this confusion. Reported-by: Boqun Feng <boqun.feng@xxxxxxxxx> Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx> Reviewed-by: Josh Triplett <josh@xxxxxxxxxxxxxxxx> --- Documentation/memory-barriers.txt | 1 - 1 file changed, 1 deletion(-) diff --git a/Documentation/memory-barriers.txt b/Documentation/memory-barriers.txt index 2ba8461..d336e4d 100644 --- a/Documentation/memory-barriers.txt +++ b/Documentation/memory-barriers.txt @@ -1789,7 +1789,6 @@ The Linux kernel has a number of locking constructs: (*) mutexes (*) semaphores (*) R/W semaphores - (*) RCU In all cases there are variants on "ACQUIRE" operations and "RELEASE" operations for each construct. These operations all imply certain barriers: -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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