Re: [PATCH] ide/libata: fix ata_id_is_cfa()

[Jeff Garzik <jgarzik@pobox.com>]

Sergei Shtylyov wrote:
> Alan Cox wrote:
> 
>>>>>> +    if (id[ATA_ID_MAJOR_VER] == 0xFFFF)
>>>>>> +        return 0;
>>>>>> +    return (id[ATA_ID_MAJOR_VER] & (1 << v)) ? 1 : 0;
> 
>>>>>   Refer to afa_dev_cf_sata() on how it's done in really optimal way.
> 
>>>> To what ? - there is no ata or afa_dev_cf_sata ?
> 
>>>    Very funny. Meant to be ata_dev_is_sata(), of course.
> 
>> We don't have one of those either - do you mean ata_id_is_sata ? If so
>> then yes that looks like it might be slightly cleaner although its
>> probably one instruction difference from the .s files.
> 
>    That extra *if* cost more than instruction I think.

Either way, this is irrelevant, since this isn't used in any hot path 
that I am aware of... :)

Alan just posted a reasonable explanation in the "The logic is this" 
email, maybe we can reboot the discussion from there?

Responding to a side point, I don't think its a big deal to combine 
fixes and improvements into a single patch, if you are dealing with the 
same few lines of code.  Just make sure the patch description (and/or 
code comment) enumerates the fixes and improvements both...

	Jeff