Re: [PATCH] Driver Core update for 2.6.4

Andi Kleen
2004-03-17T00:01:26Z

On Tue, Mar 16, 2004 at 11:40:39AM -0800, Greg KH wrote:
> On Tue, Mar 16, 2004 at 05:14:47PM +0100, Andi Kleen wrote:
> > Andrew Morton <akpm@osdl.org> writes:
> > >
> > > eh? If there is any argument against this code it is that it is so simple
> > > that the thing which it abstracts is not worth abstracting. But given that
> > > it is so unwasteful, this seems unimportant.
> >
> > The bloat argument was about the additional pointer in the dynamic
> > data structure (on a 64bit architecture it costs 12 bytes)
>
> Well balance that out against every usb driver re-implemeting the same
> get/put logic with an atomic counter and that "bloat of a pointer" just

Yes, all those one and two liners duplicated ... scary.

> got lost in the noise of the extra kernel code size increase :)

Have you ever looked how many instructions

if (!atomic_dec_and_test(&foo->ref))
release(foo)

generated? Code size makes no difference here at all.

Dynamic object bloat is much worse than code bloat anyways because you
can have thousands of these objects.

-Andi