Section 9.5: Nobody expects the Spanish Acquisition!

[Elad Lahav <e2lahav@gmail.com>]

Hi Paul,

As promised, I have a potentially more interesting comment regarding
Section 9.5. Throughout this section, from the very first example, the
writer uses release semantics, but the readers are not obligated to
use acquire semantics, at least on sensible architectures (with
apologies to employees of HP nee Compaq nee Digital).

If I understand correctly, these relaxed semantics are the result of
an address dependency, with the data protected by the RCU critical
section residing in a structure whose address is stored by the pointer
dereferenced by a reader. The reader cannot consider any data outside
of this structure as protected by the critical section. This is a
critical point without which the examples won't work reliably.

Am I missing something? If not, I think that this point should be
emphasized early on, with a link to Section 15.2.3.

--Elad