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


[Xen-devel] RE: [PATCH] Allocate vmcs pages when system booting

To: Keir Fraser <keir.fraser@xxxxxxxxxxxxx>, "xen-devel@xxxxxxxxxxxxxxxxxxx" <xen-devel@xxxxxxxxxxxxxxxxxxx>
Subject: [Xen-devel] RE: [PATCH] Allocate vmcs pages when system booting
From: "Jiang, Yunhong" <yunhong.jiang@xxxxxxxxx>
Date: Thu, 12 Nov 2009 23:15:22 +0800
Accept-language: en-US
Acceptlanguage: en-US
Delivery-date: Thu, 12 Nov 2009 07:15:45 -0800
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <C721D462.BE92%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: <E2263E4A5B2284449EEBD0AAB751098418E55575CE@xxxxxxxxxxxxxxxxxxxxxxxxxxxx> <C721D462.BE92%keir.fraser@xxxxxxxxxxxxx>
Sender: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
Thread-index: Acpjhi/FowWYJHS9QX+XJREOh9n85gABERxSAAcM60AAAK2pHwAAFsqw
Thread-topic: [PATCH] Allocate vmcs pages when system booting
Keir Fraser wrote:
> On 12/11/2009 14:58, "Jiang, Yunhong" <yunhong.jiang@xxxxxxxxx> wrote:
>>> Can you try this alternative fix please?
>> Yes, spin_debug_disable() is the first idea come into my mind, I
>> change my mind because the spin_debug is a global variable.  disable
>> spin_debug() before start_secondary means maybe we can't catch error
>> happens at that window, so I choose this method. Previously I
>> thought high-end system support cpu hotplug may not care about the
>> 64 pages :$ 
> CONFIG_HOTPLUG_CPU is not a user-accessible build option. In
> fact manually
> disabling it in config.h resulted in a broken build, and now I
> basically stripped out the non-HOTPLUG_CPU code (in c/s 20431). So
> this 
> would be an
> overhead for absolutely everyone.
>> Or you assume this window is quite small, and we can assume safely
>> if a error happening at this window, it will happen in other
>> timeslot in the end, sepecially this function itself don't need the
>> check? 
> Exactly. The spinlock debug checking can be best effort. I did
> think about
> allowing the checks to be disabled per-cpu, but I don't think
> it's worth it.

Agree, it don't need be per-cpu.

> I will check in my suggested fix, then.

Ok, I will work this way tomorrow.

Yunhong Jiang

> -- Keir
Xen-devel mailing list

<Prev in Thread] Current Thread [Next in Thread>