[gentoo-dev] Loading Modules from Init Scripts?

[gentoo-dev] Loading Modules from Init Scripts?

[Chad M. Huneycutt]

Hi all,
    Do we have a policy about init scripts loading modules?  I didn't think 
the scripts for any packages that I have installed load modules, but I 
don't have everything installed.  It seems like the preferred way to do it 
is to have the admin put any necessary modules in /etc/modules.autoload.

    Here is why I ask.  The pcmcia init script that is installed with 
pcmcia-cs currently is outdated, but it loads the $PCIC (i82365 or 
yenta_socket) module, as well as pcmcia_core and ds.  Then it starts 
cardmgr (which will not start without ds loaded).  The init script does not 
unload the modules when it is stopped, though.

    It makes sense that if a service requires particular kernel 
functionality to be available in order to work that it should load the 
modules for that functionality.  However, this adds some overhead to the 
initscript, in that you have to determine if the module exists, load it, 
make sure it loads, etc. before starting the service.  Then what about when 
the functionality has been built into the kernel, not as a module.  Do we 
have to detect that?  That is why I think it might be easier if we make it 
policy to just eerror out and say "You have to first load these modules!" 
rather than worrying about loading them in the script.

    If we decide to load modules from the scripts, then it would be nice to 
have some convenience routines to facilitate the process, e.g.,

     load_modules pcmcia_core i82365 ds || die

or something like that, which would check to see if the modules were 
already loaded (or maybe even compiled into the kernel), and if not, then 
it would load them.

Thoughts?

Chad

Re: [gentoo-dev] Loading Modules from Init Scripts?

[Craig M. Reece]

On Friday 25 January 2002 05:31 pm, Chad M. Huneycutt wrote thusly:
> Hi all,
>     Do we have a policy about init scripts loading modules?  I didn't think
> the scripts for any packages that I have installed load modules, but I
> don't have everything installed.  It seems like the preferred way to do it
> is to have the admin put any necessary modules in /etc/modules.autoload.
>

My impression is that /etc/modules.autoload is used for modules that you 
_always_ want loaded. Thus, the init script should load its own needed stuff 
since we would then be assuming that the script is not _always_ run.

>     Here is why I ask.  The pcmcia init script that is installed with
> pcmcia-cs currently is outdated, but it loads the $PCIC (i82365 or
> yenta_socket) module, as well as pcmcia_core and ds.  Then it starts
> cardmgr (which will not start without ds loaded).  The init script does not
> unload the modules when it is stopped, though.
>
>     It makes sense that if a service requires particular kernel
> functionality to be available in order to work that it should load the
> modules for that functionality.  However, this adds some overhead to the
> initscript, in that you have to determine if the module exists, load it,
> make sure it loads, etc. before starting the service.  Then what about when
> the functionality has been built into the kernel, not as a module.  Do we
> have to detect that?  That is why I think it might be easier if we make it
> policy to just eerror out and say "You have to first load these modules!"
> rather than worrying about loading them in the script.
>
>     If we decide to load modules from the scripts, then it would be nice to
> have some convenience routines to facilitate the process, e.g.,
>
>      load_modules pcmcia_core i82365 ds || die
>
> or something like that, which would check to see if the modules were
> already loaded (or maybe even compiled into the kernel), and if not, then
> it would load them.
>
> Thoughts?
>

I like this method a lot better than the way the pcmcia-cs package's default 
init goes about doing things.