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Date: Wed, 16 Apr 2003 14:40:35 -0700 (PDT)
Message-Id: <20030416.144035.130217416.davem@redhat.com>
To: akpm@digeo.com
Cc: willy@debian.org, ak@muc.de, linux-kernel@vger.kernel.org, anton@samba.org,
       schwidefsky@de.ibm.com, davidm@hpl.hp.com, matthew@wil.cx,
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Subject: Re: Reduce struct page by 8 bytes on 64bit
From: "David S. Miller" <davem@redhat.com>
In-Reply-To: <20030416144311.46f32253.akpm@digeo.com>
References: <20030416133539.0ac01968.akpm@digeo.com>
	<20030416212651.GF1505@parcelfarce.linux.theplanet.co.uk>
	<20030416144311.46f32253.akpm@digeo.com>
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   From: Andrew Morton <akpm@digeo.com>
   Date: Wed, 16 Apr 2003 14:43:11 -0700
   
   Well are we sure that the `flags' and `count' fields will always fall into
   the same 256-byte range?  Wouldn't it subtly break if sizeof(struct page)
   became not a multiple of eight?  Will the compiler pad it out anyway?

As long as there is a long or pointer member, the structure
will be required to be 8 byte or better aligned.