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From: Christoph Lameter <cl@linux-foundation.org>
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To: Matt Mackall <mpm@selenic.com>
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Subject: Re: [PATCH] Export symbol ksize()
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On Sun, 15 Feb 2009, Matt Mackall wrote:

> And it -is- a category error. The fact that kmalloc is implemented on
> top of kmem_cache_alloc is an implementation detail that callers should
> not assume. They shouldn't call kfree() on kmem_cache_alloc objects
> (even though it might just happen to work), nor should they call
> ksize().

ksize does not take a kmem_cache pointer and it is mainly used for
figuring out how much space kmalloc really allocated for an object. As
such its more part of the kmalloc/kfree set of calls than the
kmem_cache_* calls.

We could add another call

	kmem_cache_size()

for symmetries sake.