From: Keir Fraser <Keir.Fraser@cl.cam.ac.uk>
To: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Xen Development Mailing List <xen-devel@lists.xensource.com>
Subject: Re: RFC: [0/2] Remove netloop by lazy copying in netback
Date: Tue, 27 Mar 2007 01:45:54 +0100 [thread overview]
Message-ID: <C22E27D2.4D93%Keir.Fraser@cl.cam.ac.uk> (raw)
In-Reply-To: <C22E2506.4D76%Keir.Fraser@cl.cam.ac.uk>
On 27/3/07 01:33, "Keir Fraser" <Keir.Fraser@cl.cam.ac.uk> wrote:
>> That works fine for the x86 case. But when it's auto-translated,
>> you won't even get a page fault in the guest because the guest PTE
>> is unchanged and completely valid.
>
> How about you invalidate the PTE for the duration of the critical section.
> It's a bit skanky, but would work around this issue quite nicely!
As an arguably better alternative, perhaps we could simply make
XENMEM_add_to_physmap an atomic switch operation (from old mapping to new
mapping)? That is probably not a very hard thing to guarantee.
So you would XENMEM_add_to_physmap over the top of the existing grant
mapping, and expect the grant to simply 'fall away' as a result of this
operation (i.e., implicit removal from physmap triggers release of the
grant).
This sounds neat to me.
-- Keir
next prev parent reply other threads:[~2007-03-27 0:45 UTC|newest]
Thread overview: 63+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-03-20 4:46 RFC: [0/2] Remove netloop by lazy copying in netback Herbert Xu
2007-03-20 4:50 ` RFC: [1/2] [XEN] gnttab: Add new op unmap_and_replace Herbert Xu
2007-03-20 4:56 ` RFC: [2/2] [NET] back: Add lazy copying Herbert Xu
2007-03-20 7:10 ` RFC: [0/2] Remove netloop by lazy copying in netback Keir Fraser
2007-03-20 10:11 ` Herbert Xu
2007-03-20 10:18 ` Keir Fraser
2007-03-22 10:50 ` Herbert Xu
2007-03-22 15:40 ` Keir Fraser
2007-03-23 3:17 ` Herbert Xu
2007-03-23 10:32 ` Keir Fraser
2007-03-23 11:42 ` Herbert Xu
2007-03-23 11:47 ` Keir Fraser
2007-03-23 13:24 ` Ian Pratt
2007-03-23 23:07 ` Santos, Jose Renato G
2007-03-23 23:29 ` Ian Pratt
2007-03-26 23:58 ` Santos, Jose Renato G
2007-03-27 13:15 ` Ian Pratt
2007-03-25 11:41 ` Herbert Xu
2007-03-25 12:27 ` Keir Fraser
2007-03-26 2:19 ` Herbert Xu
2007-03-26 18:36 ` Keir Fraser
2007-03-26 21:08 ` Herbert Xu
2007-03-27 0:33 ` Keir Fraser
2007-03-27 0:35 ` Herbert Xu
2007-03-27 0:46 ` Keir Fraser
2007-03-27 0:45 ` Keir Fraser [this message]
2007-03-27 0:52 ` Herbert Xu
2007-03-27 1:02 ` Keir Fraser
2007-03-27 1:08 ` Herbert Xu
2007-03-27 1:17 ` Herbert Xu
2007-03-27 3:34 ` Isaku Yamahata
2007-03-27 7:36 ` Keir Fraser
2007-03-27 7:44 ` Herbert Xu
2007-03-27 8:12 ` Keir Fraser
2007-03-27 8:15 ` Herbert Xu
2007-03-27 8:15 ` Isaku Yamahata
2007-03-27 7:51 ` Keir Fraser
2007-03-27 7:53 ` Herbert Xu
2007-03-27 7:59 ` Herbert Xu
2007-03-27 8:10 ` Keir Fraser
2007-03-27 8:13 ` Herbert Xu
2007-03-27 8:31 ` Keir Fraser
2007-03-27 9:20 ` Herbert Xu
2007-03-27 9:58 ` Keir Fraser
2007-03-27 10:06 ` Herbert Xu
2007-03-27 10:17 ` Keir Fraser
2007-03-27 10:25 ` Herbert Xu
2007-03-27 10:40 ` Keir Fraser
2007-03-27 11:09 ` Herbert Xu
2007-03-27 8:03 ` Keir Fraser
2007-03-27 8:22 ` Isaku Yamahata
2007-03-27 10:15 ` Herbert Xu
2007-03-27 10:19 ` Keir Fraser
2007-03-27 11:11 ` Herbert Xu
2007-03-27 13:50 ` Keir Fraser
2007-03-27 20:46 ` Herbert Xu
2007-03-28 13:05 ` Herbert Xu
2007-03-29 6:08 ` Isaku Yamahata
2007-03-27 3:41 ` Isaku Yamahata
2007-03-27 5:45 ` Herbert Xu
2007-03-20 10:22 ` Keir Fraser
2007-03-20 10:27 ` Keir Fraser
2007-03-20 11:50 ` David Edmondson
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