[Qemu-devel] Re: [PATCH v2] qemu-kvm: Speed up of the dirty-bitmap-traveling

[Anthony Liguori]

On 02/10/2010 07:20 AM, Avi Kivity wrote:
> On 02/10/2010 12:52 PM, OHMURA Kei wrote:
>   
>> dirty-bitmap-traveling is carried out by byte size in qemu-kvm.c.
>> But We think that dirty-bitmap-traveling by long size is faster than by byte
>> size especially when most of memory is not dirty.
>>
>> --- a/bswap.h
>> +++ b/bswap.h
>> @@ -209,7 +209,6 @@ static inline void cpu_to_be32wu(uint32_t *p, uint32_t v)
>>  #define cpu_to_32wu cpu_to_le32wu
>>  #endif
>>  
>> -#undef le_bswap
>>  #undef be_bswap
>>  #undef le_bswaps
>>   
>>     
>
> Anthony, is it okay to export le_bswap this way, or will you want
> leul_to_cpu()?
>   

kvm_get_dirty_pages_log_range() is kvm-specific code. We're guaranteed
that when we're using kvm, target byte order == host byte order.

So is it really necessary to use a byte swapping function at all?

Regards,

Anthony Liguori