Re: Patch?: module-init-tools/modprobe.c - use modules.dep

["Adam J. Richter" <adam@yggdrasil.com>]

Rusty Russell wrote:
>In message <20021121073912.A15349@adam.yggdrasil.com> you [Adam Richter] write:
>> 
>> --xHFwDpU9dbj6ez1V
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>> 	The following patch changes modprobe in module-init-tools-0.8
>> to use modules.dep.
>> 
>> 	Benefits:
>> 
>> 	- deletes a net of 594 lines of source code
>> 
>> 	- shrinks modprobe from 14kB to 10kB (stripped, dynamically linked),
>> 	  which is useful for boot images
>> 
>> 	- should make modprobe as fast on systems with a lot of modules as
>> 	  it was with the user level module loader,
>> 
>> 	- Restores the "include" command to the aliases file, which makes
>> 	  it simpler to have separate files for automatically generated
>> 	  aliases and user customizations.
>> 
>> 	- minor: eliminates ELF dependence from modprobe user level code

>Hmm, I like it.  But I prefer to pull the depmod code into the source
>too, to keep it all under one roof.

	I have been thinking about splitting depmod into two programs:
the program as originally designed that generates modules.dep and one
that generates hardware support files.  The latter could be
distributed in the Linux kernel tree and perhaps installed in
/lib/modules/<version>/bin/ to make it easy to change support table
formats as needed.

>The ELF dependence will go back in eventually, but that's trivial.

	I'm guessing this is for symbols.  If it's for something other
reason, I'd be curious to know it.

>Hmm, Adam, do you want to reverse positions and become
>module-init-tools maintainer?  I'll send patches to you, instead of
>vice versa.  I'll release a 0.8 with the patches I have so far, then
>hand it over if you want.

>Thoughts?
>Rusty.

	I'm honored by the offer, but I have not seen any convincing
accounting of real benefits and costs that shows that it is a win to
have the module loader in kernel memory.  I might be interested in
maintaining a small modutils that could be compiled to support either
the in-kernel module load or a user level method (or both) so as to
avoid unnecessary differences between the user level and in-kernel
methods, given that the code that is specific to the kernel module
loader would be small.

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