tree e9376caaf70b54e4b236840a1cc77a443c07b341
parent 4800a5bb13c09a572f7c74662a77c9eca229eba1
author Chris Metcalf <cmetcalf@tilera.com> 1305568779 -0400
committer Chris Metcalf <cmetcalf@tilera.com> 1305860149 -0400

arch/tile: use better definitions of xchg() and cmpxchg()

These definitions use a ({}) construct to avoid some cases where
we were getting warnings about unused return values.  We also
promote the definition to the common <asm/atomic.h>, since it applies
to both the 32- and 64-bit atomics.

In addition, define __HAVE_ARCH_CMPXCHG for TILE-Gx since it has
efficient direct atomic instructions.

Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>