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] Re: how to handle paged hypercall args?

To: Olaf Hering <olaf@xxxxxxxxx>, Jan Beulich <JBeulich@xxxxxxxxxx>
Subject: Re: [Xen-devel] Re: how to handle paged hypercall args?
From: Keir Fraser <keir@xxxxxxx>
Date: Fri, 03 Dec 2010 06:18:30 -0800
Cc: xen-devel@xxxxxxxxxxxxxxxxxxx
Delivery-date: Fri, 03 Dec 2010 06:20:28 -0800
Dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:sender:user-agent:date :subject:from:to:cc:message-id:thread-topic:thread-index:in-reply-to :mime-version:content-type:content-transfer-encoding; bh=1mLjmJqVtsBm3JOVqK8BuxRyuhlLLwvEOT7LWijHL4c=; b=RBiWy03LCwEDkZVSpAlaur+Qre1xaLk8UEfEpjPZ25SNFRUuLIvkWRwSl1CjtXFO7q 67wedIfWdTg2TdI9WptlLrPi93fF8NSN2U/HDykDS4XfUDXpyTxSb0zIGfROKO/o8p6Z BxkQQGIatPeK/r9svPo9X0VxtQ0yD2GnmdCn4=
Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=sender:user-agent:date:subject:from:to:cc:message-id:thread-topic :thread-index:in-reply-to:mime-version:content-type :content-transfer-encoding; b=jtUfwC3nawTwHDkqJYXpsEb7DdOihBSTnfCZWewQrXBxZPQ1IVsJNsa+2gPLEVosd5 La0LFcIsvZuDSoF6QmUh/9C7k/wuUs62hdKAaGLZUO5rdc6V5q8Nu/L6pFxLwzRkzHbj 25aCZmKIoYd/BbttnBNK4TZ2tl+aJqXv9XOTQ=
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <20101203090629.GB6055@xxxxxxxxx>
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>
Sender: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
Thread-index: AcuS9PWUuSdzUYbKhEmSyO3PF1tq7w==
Thread-topic: [Xen-devel] Re: how to handle paged hypercall args?
User-agent: Microsoft-Entourage/12.23.0.091001
On 03/12/2010 01:06, "Olaf Hering" <olaf@xxxxxxxxx> wrote:

>> I didn't look in detail whether that's being done in a non-intuitive
>> way elsewhere, but I can't see how the event you're waiting on
>> would ever get signaled - wouldn't you need to pass it into
>> __hvm_copy() and further down from there?
> 
> I was relying on the kind-of wakeup in p2m_mem_paging_resume().
> 
> There will be a new patch shortly.

vcpu_pause() is nestable and counted. So the vcpu_unpause() on
MEM_EVENT_FLAG_VCPU_PAUSED will not be enough to wake up a vcpu that is also
paused on a waitqueue. Once the vcou is a sleep on a waitqueue it definitely
needs wake_up() to wake it.

Of course, p2m_mem_paging_resume() is quite likely the right place to put
the wake_up() call. But you do need it in addition to the unpause on the
MEM_EVENT flag.

 -- Keir



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