Re: [bisected] kernel panic 2.6.22 -> 2.6.26-rc9+
flat view
From: Krzysztof Halasa <khc@pm.waw.pl>
Date: 2008-07-13 21:51:21
Also in:
lkml
Andrew Morton [off-list ref] writes:
quoted hunk
--- a/include/asm-arm/bitops.h~a +++ a/include/asm-arm/bitops.h@@ -277,9 +277,16 @@ static inline int constant_fls(int x) * the clz instruction for much better code efficiency. */ -#define fls(x) \ +#define __fls(x) \ ( __builtin_constant_p(x) ? constant_fls(x) : \ ({ int __r; asm("clz\t%0, %1" : "=r"(__r) : "r"(x) : "cc"); 32-__r; }) ) + +/* Implement fls() in C so that 64-bit args are suitably truncated */ +static inline int fls(int x) +{ + return __fls(x); +} +
Well, I like it more as it fixes all possible places instead of only fls64(). But... can't we just move the #define body into the inline fls(x)? Will there be other users of __fls(x)? It seems the __builtin_constant_p(x) works for inline functions. The above patch fixes the kernel panic, too. -- Krzysztof Halasa