Re: [PATCH] 2.5.1-pre5: per-cpu areas

[Rusty Russell]

In message <[e-mail]> you write:
> >>>>> On Fri, 15 Mar 2002 15:07:27 +1100, Rusty Russell <[e-mail].a
u> said:
> 
>   Rusty> Sorry, after thought, I've reverted to my original position.  the
>   Rusty> original SMP per_cpu()/this_cpu() implementations were broken.
> 
>   Rusty> They must return an lvalue, otherwise they're useless for 50% of cas
es
>   Rusty> (ie. assignment).  x86_64 can still use its own mechanism for
>   Rusty> arch-specific per-cpu data, of course.
> 
> What's your position about someone taking the address of this_cpu(foo)
> and passing it to another CPU?  IMO, the effect of this should be
> allowed to be implementation-dependent.  If you agree, perhaps it
> would be good to add a comment to this effect?

Well, if you want to do TLB tricks, sure.  I don't know if that's a
good idea (Linus seems opposed to it).  But I'll add the comment.

Rusty.
--
  Anyone who quotes me in their sig is an idiot. -- Rusty Russell.