Hi,
2010/12/21 Felipe Balbi <balbi@xxxxxx>:
> On Wed, Dec 22, 2010 at 12:14:40AM +0800, tom.leiming@xxxxxxxxx wrote:
>>
>> From: Ming Lei <tom.leiming@xxxxxxxxx>
>>
>> This patch introduces musb_readb/musb_writeb function pointer,
>> so that we can use same musb_readb/musb_writeb in one single
>> binary image to help to support multiple machines.
>>
>> Signed-off-by: Ming Lei <tom.leiming@xxxxxxxxx>
>
> This I remember asking you to make a struct musb_io_ops to pass them and
> later asking for numbers of the overhead caused by a pointer deref which
> I think it's not a lot.
If musb_io_ops is to be made, musb_read{w, l} will be involved in,
so some extra overhead is added.
> Please measure the overhead caused by function pointers, if it's
> acceptable, I rather add those operations to some sort of struct
> musb_io_ops.
OK, I will do a performance comparison between inline and function
pointers.
> I don't think there will be any difference, since you're already using
> function pointers anyway.
The function pointer is only used to musb_readb/musb_writeb,
so not make struct musb_io_ops since I don't want musb_read{w,l}/
musb_write{w,l} involved in.
thanks,
--
Lei Ming
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