[PATCH 5.4 129/165] parisc: Fix compiler warnings in debug_core.c

Greg Kroah-Hartman
2020-01-11T10:32:25Z

From: Helge Deller <deller@gmx.de>

[ Upstream commit 75cf9797006a3a9f29a3a25c1febd6842a4a9eb2 ]

Fix this compiler warning:
kernel/debug/debug_core.c: In function ‘kgdb_cpu_enter’:
arch/parisc/include/asm/cmpxchg.h:48:3: warning: value computed is not used [-Wunused-value]
48 | ((__typeof__(*(ptr)))__xchg((unsigned long)(x), (ptr), sizeof(*(ptr))))
arch/parisc/include/asm/atomic.h:78:30: note: in expansion of macro ‘xchg’
78 | #define atomic_xchg(v, new) (xchg(&((v)->counter), new))
| ^~~~
kernel/debug/debug_core.c:596:4: note: in expansion of macro ‘atomic_xchg’
596 | atomic_xchg(&kgdb_active, cpu);
| ^~~~~~~~~~~

Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
arch/parisc/include/asm/cmpxchg.h | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/arch/parisc/include/asm/cmpxchg.h b/arch/parisc/include/asm/cmpxchg.h
index f627c37dad9c..ab5c215cf46c 100644
--- a/arch/parisc/include/asm/cmpxchg.h
+++ b/arch/parisc/include/asm/cmpxchg.h
@@ -44,8 +44,14 @@ __xchg(unsigned long x, __volatile__ void *ptr, int size)
** if (((unsigned long)p & 0xf) == 0)
** return __ldcw(p);
*/
-#define xchg(ptr, x) \
- ((__typeof__(*(ptr)))__xchg((unsigned long)(x), (ptr), sizeof(*(ptr))))
+#define xchg(ptr, x) \
+({ \
+ __typeof__(*(ptr)) __ret; \
+ __typeof__(*(ptr)) _x_ = (x); \
+ __ret = (__typeof__(*(ptr))) \
+ __xchg((unsigned long)_x_, (ptr), sizeof(*(ptr))); \
+ __ret; \
+})

/* bug catcher for when unsupported size is used - won't link */
extern void __cmpxchg_called_with_bad_pointer(void);
--
2.20.1