Re: [PATCH] likely cleanup: remove unlikely for kfree(NULL)

[Arjan van de Ven <arjan@infradead.org>]

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)..

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