Re: 2.6.9-rc1-mm4 sparc reiser4 build broken - undefined atomic_sub_and_test

[Roman Zippel]

Hi,

On Tue, 14 Sep 2004, Martin Schwidefsky wrote:

> > On some archs atomic_sub_return is more complex than atomic_sub_and_test
> > and there it does make a difference.
> 
> Well even if you can save lets say 10 cycles for the atomic_sub_return
> primitive you still won't notice any difference. The code in question
> is part of the end i/o function.

It's not just about this particular piece of code, if we introduce this as 
official API, people will start using it and in some cases it might 
matter. atomic_dec_and_test() can also be implemented using 
atomic_sub_return(), but I doubt you want to replace or deprecate it.

bye, Roman
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/