Re: [PATCH] AFS: Fix file locking

Linus Torvalds
2007-07-21T01:37:37Z

On Fri, 20 Jul 2007, Nick Piggin wrote:
>
> So you did. Then to answer that, yes it could be faster because there are
> stupid volatiles sprinkled all over the bitops code so you could easily
> end up having to do more loads. Does it make a real difference? Unlikely,
> but David loves counting cycles :)

I thought we long long since removed the volatiles. They are buggy and
horrible, and we really want to let the compiler combine multiple
test-bits, and if they matter that implies locking is buggy or something
worse..

Ie we'd *want*

if (test_bit(x, y) || test_bit(z,y))

to be rewritten by the compiler as testing bits x/z at the same time.

But now I'm too scared to look.

Linus