Re: [2.6 patch] make UNIX a bool

[Adrian Bunk]

On Thu, Mar 02, 2006 at 09:40:17PM +0100, Jesper Juhl wrote:
> On 3/2/06, Adrian Bunk <bunk@xxxxxxxxx> wrote:
> > On Thu, Mar 02, 2006 at 09:28:15PM +0100, Jesper Juhl wrote:
> > > On 3/2/06, Adrian Bunk <bunk@xxxxxxxxx> wrote:
> > > > On Thu, Mar 02, 2006 at 12:31:34PM +1100, Herbert Xu wrote:
> > > > > Adrian Bunk <bunk@xxxxxxxxx> wrote:
> > > > > >
> > > > > > It does also matter in the kernel image size case, since you have to put
> > > > > > enough modules to the other medium for having a effect bigger than the
> > > > > > kernel image size increase from setting CONFIG_MODULES=y.
> > > > >
> > > > > That's not very difficult considering the large number of modules that's
> > > > > out there that a system may wish to use.
> > > > >...
> > > >
> > > > This might be true for full-blown desktop systems - but these do not
> > > > tend to be the systems where kernel image size matters that much.
> > > > Smaller kernel image size might be an issue e.g. for distribution
> > > > kernels, but in a much less pressing way.
> > > >
> > > > The systems where kernel image size really matters are systems with few
> > > > modules where you know in advance which modules you might need. I played
> > > > a bit with the ARM defconfigs, and if you consider that you can't build
> > > > the filesystem for accessing your modules modular I haven't found any
> > > > where making everything modular would have given a real kernel image
> > > > size gain compared to the CONFIG_MODULES=n case.
> > > >
> > >
> > > I believe the basic question is this: What do we win by making
> > > CONFIG_UNIX a bool?
> > >...
> >
> > We do not have to export symbols we don't want to export to modules but
> > needed by CONFIG_UNIX.
> >
> 
> I'm probably exposing my ignorance here, but, what symbols would those be?
> 
> and does it outweigh the harm done to people who want or need
> CONFIG_UNIX modular ?


Can anyone bring real life examples for this pretended harm?

All examples I have heard until now fall under one of the following:
- CONFIG_MODULES=n wouldn't be worse
- if you want your kernel to fit on a floppy, CONFIG_UNIX shouldn't be 
  the thing making the difference between the kernel fitting on the
  floppy and the kernel not fitting on the floppy


And I'm surprised that everyone thinks the world would stop turning if 
the kernel image size is increased by CONFIG_UNIX=y, but the same people 
were quiet when during the 2.5 development the discarding of __exit code 
moved from link time to run time on some architectures (e.g. i386) 
making the kernel image size bigger for everyone.

Is there much FUD in this thread or why do people pretend to care in the 
CONFIG_UNIX case but don't care when the __exit code is discarded?


> Jesper Juhl <jesper.juhl@xxxxxxxxx>

cu
Adrian

-- 

       "Is there not promise of rain?" Ling Tan asked suddenly out
        of the darkness. There had been need of rain for many days.
       "Only a promise," Lao Er said.
                                       Pearl S. Buck - Dragon Seed

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