Re: allocating memory during kernel startup

[Andrew Doran <ad%NetBSD.org@localhost>]

On Fri, May 07, 2010 at 11:19:58AM +0900, Masao Uebayashi wrote:
> On Thu, May 06, 2010 at 02:32:57PM -0400, Michael wrote:
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> > Hello,
> > 
> > I recently ran into this problem - there is no easy way to determine
> > wether it is safe to call kmem_alloc() yet ( as in, are we far
> > enough through startup ) and when we call it too early the whole
> > thing just hangs.
> 
> We have no clear definition of the kernel state - what is boot, startup,
> and when it's done.
> 
> > Any chance to just have kmem_alloc() immediately return NULL if it
> > isn't ready yet so we can fail gracefully instead of hanging?
> 
> I like panic().

Even better, KASSERT().

> I think that complicating memory allocation in bootstrap is not a good
> thing.  What is your purpose?

Right, on the face of it I don't see why this is something to be handled at
runtime.

> Masao
> 
> > 
> > have fun
> > Michael
> > 
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> -- 
> Masao Uebayashi / Tombi Inc. / Tel: +81-90-9141-4635