Re: Modules loading modules?

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

On Sun, 1 Aug 2010, John Nemeth wrote:

>     I'm thinking the acquisition of module_lock should be pushed into
> module_autoload() instead of having the caller acquire it for this very
> reason.  It makes it hard to change the way locking works in the
> MODULAR code if you expect the caller to acquire the lock.  I don't
> know why it was done this way originally, or what the consequences (if
> any) would be for making the change.  Andrew, any thoughts on this?

I was thinking the same thing.

There is one case in kern/kern_exec.c where the lock was held while the 
code loops through a list of possible modules.  Looking closer, that 
code actually releases the lock and yield()s before re-acquiring it 
within the loop, so it probably could be modified without any adverse 
effects.

This would actually simplify the interface, since ALL of the routines 
would be doing their own locking, and noone in the rest of the kernel 
would need to know about the lock.




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