From mboxrd@z Thu Jan  1 00:00:00 1970
From: Zachary Amsden <zach@vmware.com>
Subject: Re: pgd_alloc and [cd]tors
Date: Thu, 16 Nov 2006 18:10:20 -0800
Message-ID: <455D1A0C.6010001@vmware.com>
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To: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Chris Wright <chrisw@sous-sol.org>, Virtualization Mailing List <virtualization@lists.osdl.org>
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Jeremy Fitzhardinge wrote:
> Is there any real use in having a ctor/dtor for the pgd cache?  Given
> that all pgd allocation happens via pgd_alloc/pgd_free, why not just
> fold the [cd]tor in?
>
> I'm asking because Xen wants pgd[3] to be unshared in the PAE case, and
> it looks to me like the easiest way to handle that is by making
> pgd_alloc/free pv-ops and doing the appropriate thing in the Xen code. =

> Would need to sort out the vmalloc mapping replication as well, but I
> think that's pretty straightforward.
>   =


Actually, vmalloc mapping replication is not quite straightforward - you =

have to replicate it under locks and track all pgds using pgd_list if =

you support large pages.

Zach