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Message-ID: <4A8426CE.5090605@vflare.org>
Date: Thu, 13 Aug 2009 20:14:30 +0530
From: Nitin Gupta <ngupta@vflare.org>
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To: Peter Zijlstra <peterz@infradead.org>
CC: Hugh Dickins <hugh.dickins@tiscali.co.uk>,
       Matthew Wilcox <willy@linux.intel.com>, Ingo Molnar <mingo@elte.hu>,
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Subject: Re: [PATCH] swap: send callback when swap slot is freed
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(resending in plain text)

On 08/13/2009 12:23 PM, Peter Zijlstra wrote:
> On Thu, 2009-08-13 at 08:00 +0530, Nitin Gupta wrote:
>>> I don't share Peter's view that it should be using a more general
>>> notifier interface (but I certainly agree with his EXPORT_SYMBOL_GPL).
>> Considering that the callback is made under swap_lock, we should not
>> have an array of callbacks to do. But what if this callback finds other
>> users too? I think we should leave it in its current state till it finds
>> more users and probably add BUG() to make sure callback is not already set.
>>
>> I will make it EXPORT_SYMBOL_GPL.
>
> If its such a tightly coupled system, then why is compcache a module?
>

Keeping everything as separate kernel modules has been the goal of this 
project. However, this callback is the only thing which I could not do 
without this small patching.

Nitin