Re: kbuild 2.5 is ready for inclusion in the 2.5 kernel

Dave Jones
2002-05-18T01:34:00Z

On Sat, May 18, 2002 at 03:14:10AM +0200, Andrea Arcangeli wrote:
> you're right if we need a make clean it's because the buildsystem is
> broken. However one thing that happens all the time to me, is that I
> change an header like mm.h or sched.h and ~everything needs to be
> rebuilt then.

Yep. Our includes dependancies suck bigtime. Some work has been
done already in untangling the mess, but a lot more needs to be
done to really make a real difference.

Whats scary is that if you look at the dependancy graphs[1] of the
'best of the worst' includes, it's the same ugly mess we've
come to know and expect, and yet this is *after* some cleanups
already happened.

The 'dump everything into sched.h and friends' things really
needs splitting up some more, but it's a lot of work, and I don't
think kbuild2.5 alone is going to make that much difference
in this regard. Pulling out the component parts of the bigger
includes is probably the only way around this.

A driver that needs 'jiffies' defined should not be
inadvertantly pulling in a hundred include files.

Dave.

[1] ftp://ftp.kernel.org/pub/linux/kernel/people/davej/misc/graphs/

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