Subject: Re: [PATCH 0/24] make atomic_read() behave consistently across all architectures

From: Nick Piggin <[email-masked]>
Date: Fri, 17 Aug 2007 17:26:12 +1000

Satyam Sharma wrote:

> #define atomic_read_volatile(v)				\
> 	({						\
> 		forget((v)->counter);			\
> 		((v)->counter);				\
> 	})
> 
> where:

*vomit* :)

Not only do I hate the keyword volatile, but the barrier is only a
one-sided affair so its probable this is going to have slightly
different allowed reorderings than a real volatile access.

Also, why would you want to make these insane accessors for atomic_t
types? Just make sure everybody knows the basics of barriers, and they
can apply that knowledge to atomic_t and all other lockless memory
accesses as well.

> #define forget(a)	__asm__ __volatile__ ("" :"=m" (a) :"m" (a))

I like order(x) better, but it's not the most perfect name either.

-- 
SUSE Labs, Novell Inc.