Re: [PATCH v2 RFC 1/3] documentation: Add needed ACCESS_ONCE() calls to memory-barriers.txt

Peter Zijlstra
2013-11-21T21:56:06Z

On Thu, Nov 21, 2013 at 01:31:27PM -0800, Paul E. McKenney wrote:
> From: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
>
> The Documentation/memory-barriers.txt file was written before the need
> for ACCESS_ONCE() was fully appreciated. It therefore contains no
> ACCESS_ONCE() calls, which can be a problem when people lift examples
> from it. This commit therefore adds ACCESS_ONCE() calls.

So I find the repeated ACCESS_ONCE() significantly detracts from the
readability of the text.

Can't we simply state that all accesses are assumed single-copy atomic
and this can be achieved for naturally aligned words using ACCESS_ONCE()
in C/C++ ?