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/
Home Products Support Community News


Re: [Xen-devel] [PATCH][RFC] Serialize scrubbing pages

To: Keir Fraser <keir.fraser@xxxxxxxxxxxxx>
Subject: Re: [Xen-devel] [PATCH][RFC] Serialize scrubbing pages
From: Kouya Shimura <kouya@xxxxxxxxxxxxxx>
Date: Mon, 11 Aug 2008 20:07:58 +0900
Cc: xen-devel@xxxxxxxxxxxxxxxxxxx
Delivery-date: Mon, 11 Aug 2008 04:08:22 -0700
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <C4C5D06B.254B5%keir.fraser@xxxxxxxxxxxxx>
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/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe>
References: <C4C5CF0E.254B2%keir.fraser@xxxxxxxxxxxxx> <C4C5D06B.254B5%keir.fraser@xxxxxxxxxxxxx>
Sender: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
Hi Keir,

I'm afraid that cset18305:f10d436d9a9e makes free_domheap_page freeze. 
Inner loop of page_scrub_softirq which keeps page_scrub_lock takes
at least 1 millisec. Is it OK? 
That's why I prepare a new spinlock.


Keir Fraser writes:
> On 11/8/08 11:12, "Keir Fraser" <keir.fraser@xxxxxxxxxxxxx> wrote:
> > I've considered the possibility of moving this kind of thing into a service
> > domain. Then it would be visible to the scheduler and be less of a hack.
> > 
> > Anyhow, I hadn't considered the contention for the heap_lock. I think your
> > patch is good and I will apply it for 3.3.
> I've simplified the patch and then checked it in. There was no need for a
> new spinlock as it strictly dominated the old one.

Xen-devel mailing list