Subject: Re: Corret way to allocate memory in kernel ?
To: Jason Thorpe <thorpej@nas.nasa.gov>
From: Chris G Demetriou <Chris_G_Demetriou@ux2.sp.cs.cmu.edu>
List: tech-kern
Date: 08/15/1996 14:06:40
> On Thu, 15 Aug 1996 23:17:31 +1000 (EST) 
>  Darren Reed <darrenr@cyber.com.au> wrote:
> 
>  > And what about using MALLOC() vs malloc() in the kernel ?
>  > 
>  > Seems like I want to do MALLOC(), for the spl() ?
>  > 
>  > But grep'ing through a 1.1 kernel shows a fair amount of mallc()...
> 
> Most places just use malloc().  Really, MALLOC() is just an attept to 
> optimize ... you'll note that if DIAGNOSTIC is defined, it just expands 
> to a call to malloc() ... malloc() does an splimp() internally.
> 
> It's mostly a stylistic thing, I think... I usually just use malloc().

it boils down to optimization.  MALLOC should be used in 'critical
paths'.  How you do determine if something's a critical path?
"profile" is one good answer.

I just about always use malloc(), unless i have good reason to believe
that a piece of code would be used sufficiently frequently that the
inlining would be of significant benefit.


cgd