Date: Wed, 20 Feb 2008 17:30:43 +0100 (CET)
From: Jan Engelhardt <jengelh@computergmbh.de>
To: Patrick McHardy <kaber@trash.net>
cc: =?ISO-8859-15?Q?Ilpo_J=E4rvinen?= <ilpo.jarvinen@helsinki.fi>,
       netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
       David Miller <davem@davemloft.net>,
       Arnaldo Carvalho de Melo <acme@redhat.com>
Subject: Re: [RFC PATCH 3/8] [NET]: uninline dev_alloc_skb, de-bloats a lot
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On Feb 20 2008 17:27, Patrick McHardy wrote:
>> Striking. How can this even happen? A callsite which calls
>> 
>>  dev_alloc_skb(n)
>> 
>> is just equivalent to
>> 
>>  __dev_alloc_skb(n, GFP_ATOMIC);
>> 
>> which means there's like 4 (or 8 if it's long) bytes more on the
>> stack. For a worst case, count in another 8 bytes for push and pop or mov on
>> the stack. But that still does not add up to 23 kb.
>
> __dev_alloc_skb() is also an inline function which performs
> some extra work. Which raises the question - if dev_alloc_skb()
> is uninlined, shouldn't __dev_alloc_skb() be uninline as well?
>
I'd like to see the results when {__dev_alloc_skb is externed
and dev_alloc_skb remains inlined}.
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