Re: POSIX Semaphores

[Paul Goyette <paul%whooppee.com@localhost>]

On Sun, 24 Feb 2013, Nicolas Joly wrote:

> On Sat, Feb 23, 2013 at 02:50:44PM -0800, Paul Goyette wrote:
> [...]
> > 1. (status quo) Don't touch anything, leave ksem as a module which can
> > only be (and always is) built-in.
> >
> > 2. Remove the partial MODULE-arization that has already been done, and
> > treat ksem just like any other mandatory, non-optional part of the
> > kernel.
> >
> > 3. Finish the MODULE-arization, which would enable us to unload and
> > reload the module at will, without requiring a reboot.  (The default, of
> > course, would remain including ksem in all kernels, but it would be
> > controlled by an "options BLAH" so a highly-modular kernel could be
> > configured with "nooptions BLAH".)
> >
> > Option 1 is easiest, but does it really make sense to have a non-modular
> > module?  :)
>
> The built-in module version has the advantage, over non modular one,
> that it can be disabled at run-time if needed.

True.  But option 3 has an even larger advantage in that you can 
actually replace the implementation, as well as simply disable it.


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