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Date: Tue, 09 Aug 2005 12:09:29 +0200
Message-ID: <s5hhddz1kx2.wl%tiwai@suse.de>
From: Takashi Iwai <tiwai@suse.de>
To: Adrian Bunk <bunk@stusta.de>
Cc: Pekka J Enberg <penberg@cs.Helsinki.FI>, Andrew Morton <akpm@osdl.org>,
       linux-kernel@vger.kernel.org, pmarques@grupopie.com
Subject: Re: [PATCH] kernel: use kcalloc instead kmalloc/memset
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At Mon, 8 Aug 2005 23:05:24 +0200,
Adrian Bunk wrote:
> 
> On Mon, Aug 08, 2005 at 12:11:21PM +0200, Takashi Iwai wrote:
> > At Sat, 6 Aug 2005 17:09:40 +0200,
> > Adrian Bunk wrote:
> > > 
> > > 
> > > Looking at how few is left from kcalloc, can't we make it a
> > > "static inline" function in slab.h?
> > > 
> > > This would optimize nicely for all of the users where the first or even 
> > > the first two parameters are constant at compile-time and shouldn't do 
> > > much harm for the other users.
> > > 
> > > As a side effect, the difference between kcalloc(1, ...) and kzalloc() 
> > > would become a coding style question without any effect on the generated 
> > > code.
> > 
> > How about to use __builtin_constant_p() like kmalloc?
> > The code readability would be worsen, though...
> 
> Where should this make any difference?
> 
> If the function is "static inline", gcc can e.g. always determine at 
> compile-time that 1 >= 0 can never be false and therefore optimize it 
> away.

Argh, forget my post.  It was just lack of caffeine :)


Takashi