[PATCH] m32r: __cmpxchg_u32 fix
This patch fixes a bug of include/asm-m32r/system.h:__cmpxchg_u32().
static __inline__ unsigned long
__cmpxchg_u32(volatile unsigned int *p, unsigned int old, unsigned int new);
In __cmpxchg_u32(), the "old" value must not be changed to the previous "*p"
value. But the former code modifies the previous "*p" value.
A deadlock at _atomic_dec_and_lock sometimes happened due to this bug.
Signed-off-by: Hayato Fujiwara <fujiwara@linux-m32r.org>
Signed-off-by: Hirokazu Takata <takata@linux-m32r.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/include/asm-m32r/system.h b/include/asm-m32r/system.h
index 06c12a0..d6a2c61 100644
--- a/include/asm-m32r/system.h
+++ b/include/asm-m32r/system.h
@@ -239,7 +239,7 @@
" bra 2f; \n"
" .fillinsn \n"
"1:"
- M32R_UNLOCK" %2, @%1; \n"
+ M32R_UNLOCK" %0, @%1; \n"
" .fillinsn \n"
"2:"
: "=&r" (retval)