Re: [PATCH] net/8021q/vlan_dev.c - Use print_mac

[Patrick McHardy <kaber-dcUjhNyLwpNeoWH0uzbU5w@public.gmane.org>]

David Miller wrote:
> From: Patrick McHardy <kaber-dcUjhNyLwpNeoWH0uzbU5w@public.gmane.org>
> Date: Mon, 18 Feb 2008 16:19:40 +0100
>
>   
>> Joe Perches wrote:
>>     
>>>
>>>> We specifically removed this sort of thing, please don't
>>>> add it back.
>>>>         
>> Why?
>>     
>
> We converted the entire tree over the print_mac(), and since
> the MAC_FMT stuff was therefore no longer used we could
> remove it.
>
> Some references slipped back in somehow, and thus MAC_FMT
> did too.
>
> There is no reason to keep around a global interface for
> _one_ user when that user can use the recommended interface
> just as equally as the rest of the tree which we converted.
>
> This is a pr_debug() statement we're talking about here.
> :-)
>   

The way pr_debug is implemented it still results in two function
calls per packet since the compiler doesn't know that it doesn't
have visible side-effects besides modifying the (unused) buffer.
I confirmed this using codiff.