Re: Difference between atomic operations and memory barriers

From: Stefan Richter
Date: Mon Oct 26 2009 - 15:34:33 EST


Noah Watkins wrote:
>> So we can safely assume that pointer assignment will be done in an
>> atomic manner?
>
> See the the comment above rcu_assign_pointer in
> include/linux/rcupdate.h

This comment only talks about ordering, not about atomicity.

Again, AFAIR the ISO C spec should explain what is going to be
guaranteed atomic and what might not be atomic.

rcu_assign_pointer() itself does rely on atomicity of pointer
assignments though, like lots of code elsewhere in the kernel.
--
Stefan Richter
-=====-==--= =-=- ==-=-
http://arcgraph.de/sr/
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