[PATCH v2] arch: tile: include: asm: add cmpxchg64() definition

[Chen Gang]

Need add cmpxchg64(), or will cause compiling issue.

Need define it as cmpxchg() only for 64-bit operation, since cmpxchg()
can support 8 bytes.

The related error (with allmodconfig):

  drivers/block/blockconsole.c: In function âbcon_advance_console_bytesâ:
  drivers/block/blockconsole.c:164:2: error: implicit declaration of function âcmpxchg64â [-Werror=implicit-function-declaration]

Signed-off-by: Chen Gang <gang.chen@xxxxxxxxxxx>
---
 arch/tile/include/asm/cmpxchg.h |    6 ++++++
 1 files changed, 6 insertions(+), 0 deletions(-)

diff --git a/arch/tile/include/asm/cmpxchg.h b/arch/tile/include/asm/cmpxchg.h
index 276f067..1da5bfb 100644
--- a/arch/tile/include/asm/cmpxchg.h
+++ b/arch/tile/include/asm/cmpxchg.h
@@ -68,6 +68,12 @@ extern unsigned long __cmpxchg_called_with_bad_pointer(void);
 
 #define tas(ptr) (xchg((ptr), 1))
 
+#define cmpxchg64(ptr, o, n)						\
+({									\
+	BUILD_BUG_ON(sizeof(*(ptr)) != 8);				\
+	cmpxchg((ptr), (o), (n));					\
+})
+
 #endif /* __ASSEMBLY__ */
 
 #endif /* _ASM_TILE_CMPXCHG_H */
-- 
1.7.7.6
--
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/