Re: [PATCH RFC 0/7] x86: convert ticketlocks to C and remove duplicatecode

[Jeremy Fitzhardinge]

On 06/21/2011 07:01 AM, Peter Zijlstra wrote:
> No complaints from me, I rather like the result.

OK, good.

> One other thing you could contemplate is adding something like:
>
> #define xadd(ptr, inc)							\
> do {									\
> 	switch(sizeof(*(ptr))) {					\
> 	case 1:								\
> 		asm volatile (LOCK_PREFIX "xaddb %0, %1\n"		\
>                              : "+r" (inc), "+m" (*(ptr))		\
>                              : : "memory", "cc");			\
> 	case 2:
> 		... xaddw ...
> 	case 4:
> 		... xaddl ...
> } while (0)
>
> and a similar something for inc. For both there seem to be various asm
> bits left (we could even consider adding xadd to
> arch/x86/include/asm/cmpxchg*.h).
>
> Also, you might have wanted to CC Linus on this, he's usually interested
> in these bits.

OK, I'll add the xadd/inc helpers and repost.

    J
--
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/