Re: [PATCH 3/4] Add __global tag where needed.

David Woodhouse
2006-08-25T10:34:41Z

On Fri, 2006-08-25 at 12:26 +0200, Adrian Bunk wrote:
> On Fri, Aug 25, 2006 at 10:52:26AM +0100, David Woodhouse wrote:
> > On Thu, 2006-08-24 at 23:30 +0200, Adrian Bunk wrote:
> > > Applying this doesn't seem to make much sense until it's clear whether a
> > > "build everything except for assembler files at once" approach (that
> > > needs less globals) or your current "compile only multi-obj at once"
> > > approach (that requires more globals).
> >
> > For the kernel itself, I think that building a directory at once is the
> > way forward. For modules, obviously the scope is more limited.
>
> For any desktop or server you buy today your patches are a nice
> improvement but not that important.

Yes, I agree -- although I haven't tested for performance yet; there
_may_ be something surprisingly improved in there but I suspect it's
unlikely.

> But projects like embedded systems or OLPC that really need want
> kernels should be the same projects that already avoid the
> 10% size penalty of CONFIG_MODULES=y.

OLPC has USB ports and wants to be fairly flexible about being able to
connect stuff -- I don't think we can turn off CONFIG_MODULES in its
running kernel. However, its _boot_ kernel (LinuxBIOS) has
CONFIG_MODULES=n, and that's where we _really_ care about the space.

--
dwmw2