[PATCH] __cmpxchg() must really always be inlined on alpha

With the latest 2.6.15 kernel builds for alpha on Debian, we ran into a
problem with undefined references to __cmpxchg_called_with_bad_pointer() in
a couple of kernel modules (xfs.ko and drm.ko; see
http://bugs.debian.org/347556).

It looks like people have been trying to out-clever each other wrt the
definition of "inline" on this architecture :), with the result that
__cmpxchg(), which must be inlined so the compiler can see its argument is
const, is not guaranteed to be inlined.  Indeed, it was not being inlined
when building with -Os.

The attached patch fixes the issue by adding an
__attribute__((always_inline)) explicitly to the definition of __cmpxchg()
instead of relying on redefines of "inline" elsewhere to make this happen.

Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>