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SubjectRe: Portable binary modules
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[Horst von Brand]

> The locking primitives are inlined for performance, and radically
> different in both cases. The UP kernel has a definite advantage
> speedwise by _not_ handling SMP locks. Your idea is to compile
> everything as SMP then?

Just the module. If inserted into a UP kernel, grabbing the lock
would never fail. Is it really impossible to do this? (Please
educate me.) The only cost I see is the memory for the locks which
the UP kernel needs to allocate, even though it will never use
them.[1]

> > In many cases binary modules could easily be built as SMP compatible
> > without any real performance hit on the system. If there is a
> > performance hit, the developer can build both SMP and UP versions of
> > the modules.
>
> And for large memory, and not. And for i386, i486, i586 and
> i686. And so on. Get real.

It is a pain to maintain hundreds of machines which vary in subtle
ways. If I could compile a module _once_ and rdist it to all the
workstations, it would make life a lot easier.

I don't see why it is so evil to reduce the variables when compiling a
module. Combinatorial growth and all that.


Kjetil T.

[1] It looks like the memory _is_ allocated if you compile with GCC < 2.8...

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