Re:Possible kernel optimizati
Tekno Soft Snc (MC3641@mclink.it)
Fri, 13 Dec 96 15:59:26 CET
>> this is an idea that I think possible.
>>
>> It is possible to fit all the driver initialization & probing code in a
>> separate ELF section that can be discarded after kernel initializations
?
>>
>> This code, after the kernel initialization, is unused, why don't free
it ?
>
> heh :) when i first read the ELF standard i came up with the very same
> idea ... then i was told that this idea is almost as old as Linux
itself,
> and that it comes up regularly on linux-kernel, but nobody has done it
so
> far.
>
> now that we definitely do ELF bootloading only, it's the right time to
> start thinking about the details? :)
>
> btw, imho it would be cleaner if we did it this way:
>
> - define an 'init module'. This 'module' can be unloaded after booting
> has finished. Just by calling 'rmmod initmodule' from user-space.
>
> the boot code has to set up this 'module', and we need support from the
> kernel image linker too. The kernel could decrease the kernel usage
> counter once all init functions in it were called?
Hmmm! I guess that can be done in this way:
- Fitting the initialization code in a section (gcc the do this with
a directive like #pragma section xyz ? I don't know the gcc very well)
- The linker can fit all the inizialization code in a separate ELF section
(like new exceptions handling), a this point we know the section
start/end
address (this section must be aligned to a page ?)
- After the kernel initialization we can mark this section (=group of
pages),
we know the start/end address, as free.
Roberto Fichera - email MC3641@mclink.it
Xmeo ver.3.0 Alpha for Linux & Windows