WARNING - OLD ARCHIVES

This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
   
 
 
Xen 
 
Home Products Support Community News
 
   
 

xen-devel

Re: [Xen-devel] [PATCH] respin of mprotect performance patch

To: "Keir Fraser" <Keir.Fraser@xxxxxxxxxxxx>, <xen-devel@xxxxxxxxxxxxxxxxxxx>
Subject: Re: [Xen-devel] [PATCH] respin of mprotect performance patch
From: "Bruce Rogers" <brogers@xxxxxxxxxx>
Date: Sat, 12 Jan 2008 20:08:06 -0700
Delivery-date: Sat, 12 Jan 2008 19:28:56 -0800
Envelope-to: www-data@xxxxxxxxxxxxxxxxxx
In-reply-to: <C3AE5951.12129%Keir.Fraser@xxxxxxxxxxxx>
List-help: <mailto:xen-devel-request@lists.xensource.com?subject=help>
List-id: Xen developer discussion <xen-devel.lists.xensource.com>
List-post: <mailto:xen-devel@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe>
References: <47826C1C.5C6B.0048.1@xxxxxxxxxx> <C3AE5951.12129%Keir.Fraser@xxxxxxxxxxxx>
Sender: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
I made a few tweaks to your patch as follows:
As I see it we need to preserve the existing AD bits but additionally OR in the 
AD bits being passed in (see behavior of pte_modify(), where it preserves 
current AD in use of _PAGE_CHG_MASK along with ORing in newprot bits, which 
include AD bits (A at least).)
See update_intpte() for this change.

Also we need to remove cmd value from req.ptr in do_mmu_update..

Updated Linux patch is also included.

Let me know if I'm missing the point some how.

Signed-off-by: Bruce Rogers <brogers@xxxxxxxxxx>

- Bruce

>>> On Sat, Jan 12, 2008 at  4:47 AM, in message
<C3AE5951.12129%Keir.Fraser@xxxxxxxxxxxx>, Keir Fraser
<Keir.Fraser@xxxxxxxxxxxx> wrote: 
> Bruce,
> 
> Attached is my equivalent implementation of ATOMIC_PT_UPDATE. Notice that I
> changed the name to MMU_PT_UPDATE_PRESERVE_AD, also that I removed a bunch
> of code duplication albeit at the expense of passing yet another parameter
> around.
> 
> Could you rev your Linux patch and give it a spin?
> 
>  Thanks,
>  Keir
> 
> On 8/1/08 01:05, "Bruce Rogers" <brogers@xxxxxxxxxx> wrote:
> 
>> I've incorporated the comments of Jan and Keir into the attached patches, 
> with
>> the exception of moving mmu_ops related entries from public/xen.h into
>> architecture specific headers.
>> Thanks for your review.  Let me know if I've missed anything.
>> 
>> Signed-off-by: Bruce Rogers <brogers@xxxxxxxxxx>
>> 
>> - Bruce
>> 
>> _______________________________________________
>> Xen-devel mailing list
>> Xen-devel@xxxxxxxxxxxxxxxxxxx
>> http://lists.xensource.com/xen-devel


Attachment: 01-preserve-ad.patch
Description: Text document

Attachment: linux_mprotect_perf.patch
Description: Text document

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel