[PATCH V4] powerpc: Implement {cmp}xchg for u8 and u16

[Pan Xinhui]

On 2016年04月28日 15:59, Peter Zijlstra wrote:
> On Wed, Apr 27, 2016 at 05:16:45PM +0800, Pan Xinhui wrote:
>> From: Pan Xinhui <xinhui.pan at linux.vnet.ibm.com>
>>
>> Implement xchg{u8,u16}{local,relaxed}, and
>> cmpxchg{u8,u16}{,local,acquire,relaxed}.
>>
>> It works on all ppc.
>>
>> remove volatile of first parameter in __cmpxchg_local and __cmpxchg
>>
>> Suggested-by: Peter Zijlstra (Intel) <peterz at infradead.org>
>> Signed-off-by: Pan Xinhui <xinhui.pan at linux.vnet.ibm.com>
> 
> Generally has the right shape; and I trust others to double check the
> ppc-asm minutia.
> 
> Acked-by: Peter Zijlstra (Intel) <peterz at infradead.org>
> 
> 
thanks!