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From: ebiederm@xmission.com (Eric W. Biederman)
To: Peter Zijlstra <peterz@infradead.org>
Cc: Yinghai Lu <yhlu.kernel@gmail.com>, Ingo Molnar <mingo@elte.hu>,
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Date: Thu, 31 Jul 2008 15:14:57 -0700
In-Reply-To: <1217541108.8157.108.camel@twins> (Peter Zijlstra's message of
	"Thu, 31 Jul 2008 23:51:48 +0200")
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Subject: Re: [PATCH 0/3] dyn_array support #2
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Peter Zijlstra <peterz@infradead.org> writes:

> On Wed, 2008-07-30 at 21:09 -0700, Yinghai Lu wrote:
>> please check the patches adding dyn_array and nr_irqs #2
>
> Why can't we use a radix tree like powerpc does?

Unless I am mistaken the ppc uses the radix tree for something
different.  We don't have any architecture in the kernel to
my knowledge that doesn't use an array of irq_desc entries.

Killing the array of irq_desc entries and along with it
NR_IRQS is what needs to happen.

Eric