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Date: Fri, 7 Jan 2005 19:32:40 +0000
From: Christoph Hellwig <hch@infradead.org>
To: Paulo Marques <pmarques@grupopie.com>
Cc: Vladimir Saveliev <vs@namesys.com>, linux-mm <linux-mm@kvack.org>,
       Andrew Morton <akpm@osdl.org>,
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       Christoph Hellwig <hch@infradead.org>
Subject: Re: [RFC] per thread page reservation patch
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On Fri, Jan 07, 2005 at 07:14:15PM +0000, Paulo Marques wrote:
> This seems like a very asymmetrical behavior. If the code explicitly 
> reserves pages, it should explicitly use them, or it will become 
> impossible to track down who is using what (not to mention that this 
> will slow down every regular user of __alloc_pages, even if it is just 
> for a quick test).
> 
> Why are there specialized functions to reserve the pages, but then they 
> are used through the standard __alloc_pages interface?

That seems to be the whole point of the patch, as that way it'll serve
all sub-allocators or kernel function called by the user.  Without this
behaviour the caller could have simply used a mempool.