diff options
| author | Andreas Larsson <andreas@gaisler.com> | 2014-11-05 15:52:08 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-11-21 09:22:52 -0800 |
| commit | 96920746658f98dbdaccc90ab818443471accc89 (patch) | |
| tree | 90c3956ca5c0d736056e45ae5fa1b9136edb8459 /arch/sparc/include/asm/atomic_32.h | |
| parent | 134712463afbd65c6b11193cd8000c83fc5b3a1b (diff) | |
sparc32: Implement xchg and atomic_xchg using ATOMIC_HASH locks
[ Upstream commit 1a17fdc4f4ed06b63fac1937470378a5441a663a ]
Atomicity between xchg and cmpxchg cannot be guaranteed when xchg is
implemented with a swap and cmpxchg is implemented with locks.
Without this, e.g. mcs_spin_lock and mcs_spin_unlock are broken.
Signed-off-by: Andreas Larsson <andreas@gaisler.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/sparc/include/asm/atomic_32.h')
| -rw-r--r-- | arch/sparc/include/asm/atomic_32.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/sparc/include/asm/atomic_32.h b/arch/sparc/include/asm/atomic_32.h index 905832aa9e9e..a0ed182ae73c 100644 --- a/arch/sparc/include/asm/atomic_32.h +++ b/arch/sparc/include/asm/atomic_32.h @@ -21,7 +21,7 @@ extern int __atomic_add_return(int, atomic_t *); extern int atomic_cmpxchg(atomic_t *, int, int); -#define atomic_xchg(v, new) (xchg(&((v)->counter), new)) +extern int atomic_xchg(atomic_t *, int); extern int __atomic_add_unless(atomic_t *, int, int); extern void atomic_set(atomic_t *, int); |