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Date: Mon, 5 May 2003 18:52:48 -0700
From: Andrew Morton <akpm@digeo.com>
To: Rusty Russell <rusty@rustcorp.com.au>
Cc: dipankar@in.ibm.com, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] kmalloc_percpu
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Rusty Russell <rusty@rustcorp.com.au> wrote:
>
> > +#define PERCPU_POOL_SIZE 32768
> > 
> > What's this?
> 
> OK.  It has a size restriction: PERCPU_POOL_SIZE is the maximum total
> kmalloc_percpu + static DECLARE_PER_CPU you'll get, ever.  This is the
> main downside.  It's allocated at boot.

And is subject to fragmentation.

Is it not possible to go allocate another N * PERCPU_POOL_SIZE from
slab if it runs out?

That way, PERCPU_POOL_SIZE only needs to be sized for non-modular static
percpu data, which sounds more robust.