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From: David Howells <dhowells@redhat.com>
In-Reply-To: <45EDABC8.8040901@zytor.com> 
References: <45EDABC8.8040901@zytor.com>  <20070306173929.2708.37191.stgit@warthog.cambridge.redhat.com> 
To: "H. Peter Anvin" <hpa@zytor.com>
Cc: torvalds@osdl.org, akpm@osdl.org, benh@kernel.crashing.org,
       linux-kernel@vger.kernel.org, johannes@sipsolutions.net
Subject: Re: [PATCH] Fix get_order() 
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Date: Tue, 06 Mar 2007 18:21:39 +0000
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H. Peter Anvin <hpa@zytor.com> wrote:

> 	if (size <= (1UL << page_shift))
> 		return 0;
> 	else
> 		return __ilog2_u32(size-1)+1-page_shift;

I think you're right.  That'll also defend against the result of __ilog2_u32()
being less than page_shift-1.

I think I can dispense with the page_shift argument.  IIRC __get_order() was
overridden by some arch, but isn't now.

David