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Date: Sun, 27 Jan 2008 22:56:41 +0100
From: "Vegard Nossum" <vegard.nossum@gmail.com>
To: "Pekka Enberg" <penberg@cs.helsinki.fi>
Subject: Re: lib/idr.c: initialize struct idr_layer
Cc: "Jim Houston" <jim.houston@ccur.com>, "Ingo Molnar" <mingo@elte.hu>,
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On Jan 27, 2008 10:35 PM, Pekka Enberg <penberg@cs.helsinki.fi> wrote:
> > I think there's a pretty big chance I'm wrong (or misunderstanding
> > something) here, so I'll just ask:
> > setup_object() from mm/slub.c is what calls the ctor. Shouldn't this
> > be called from slab_alloc() as well? (I'm marking the data
> > "uninitialized" there before returning the object.) Otherwise you
> > might get back an object that is initialized with the previous owner's
> > data. Or is this intentional?
>
> It's intentional. The caller of kmem_cache_free() is expected to put
> the object in such a state that it can be recycled immediately when
> kmem_cache_alloc() for that cache is called. You can find the design
> rationale for that in Bonwick's original paper on slab:
> http://citeseer.ist.psu.edu/bonwick94slab.html

Ow. I guess this is the end of the thread, then :-) My fault. Thanks!

Vegard