Arjan van de Ven wrote:
> On Thu, 2006-04-27 at 10:56 +0200, Adrian Bunk wrote:
>> On Thu, Apr 27, 2006 at 10:41:12AM +0200, Arjan van de Ven wrote:
>>> On Thu, 2006-04-27 at 10:31 +0200, Adrian Bunk wrote:
>>>> On Thu, Apr 27, 2006 at 08:50:40AM +0200, Arjan van de Ven wrote:
>>>>> On Thu, 2006-04-27 at 09:28 +0300, Pekka J Enberg wrote:
>>>>>> On Thu, 27 Apr 2006, Nick Piggin wrote:
>>>>>>> Not to dispute your conclusions or method, but I think doing a
>>>>>>> defconfig or your personal config might be more representative
>>>>>>> of % size increase of text that will actually be executed. And
>>>>>>> that is the expensive type of text.
>>>>>> True but I was under the impression that Arjan thought we'd get text 
>>>>>> savings with GCC 4.1 by making kfree() inline.
>>>>> not savings in text size, I'll settle for the same size.
>>>>> ...
>>>> It will always be bigger since there are cases where it's unknown at 
>>>> compile time whether it will be NULL when called.
>>> if it's "unknown" you could call into a separate kfree() which does
>>> check out of line. (sure that's a dozen bytes bigger but that is
>>> noise ;)
>> It's noise and _much work.
> 
> not if the compiler can do it. The *compiler* knows a lot (4.1 at
> least)..

I would think so too. Unfortunately this is what I found for make
allyesconfig on 2.6.16.9:

   text    data     bss     dec     hex filename
21615935 7929490 2187672 31733097        1e43569 vmlinux-3.3.5-new
21616824 7929298 2187672 31733794        1e43822 vmlinux-3.3.5-old
21546713 7616546 2184984 31348243        1de5613 vmlinux-4.1.0-new
21546551 7616458 2184984 31347993        1de5519 vmlinux-4.1.0-old

Where "old" is the original one, and "new" the one with the included
patch applied. So the patch is a small win with gcc-3.3.5 and a small
loss on gcc-4.1.0. I don't really understand why 4.1.0 produces larger
code with the patch, but I triple-checked...

Groeten,
Bart




-- 
Bart Hartgers - TUE Eindhoven - http://plasimo.phys.tue.nl/bart/contact/