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] linux: {start, stop}_hz_timer() not really affecting per

To: Jan Beulich <jbeulich@xxxxxxxxxx>
Subject: Re: [Xen-devel] linux: {start, stop}_hz_timer() not really affecting periodic timer?
From: Keir Fraser <Keir.Fraser@xxxxxxxxxxxx>
Date: Wed, 16 Jan 2008 18:26:53 +0000
Cc: xen-devel@xxxxxxxxxxxxxxxxxxx
Delivery-date: Wed, 16 Jan 2008 10:27:11 -0800
Envelope-to: www-data@xxxxxxxxxxxxxxxxxx
In-reply-to: <478E4A42.76E4.0078.0@xxxxxxxxxx>
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>
Sender: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
Thread-index: AchYbV3knJhsJsRgEdyOUgAWy6hiGQ==
Thread-topic: [Xen-devel] linux: {start, stop}_hz_timer() not really affecting periodic timer?
User-agent: Microsoft-Entourage/11.3.6.070618
On 16/1/08 17:17, "Jan Beulich" <jbeulich@xxxxxxxxxx> wrote:

>>> Immediately would mean to me that it would fire on the return path
>>> from VCPUOP_set_singleshot_timer, so HYPERVISOR_block() would
>>> not (necessarily) find any pending events and hence block when it
>>> shouldn't. Or am I missing some magic by which this is being avoided?
>> 
>> The function should only be called with interrupts disabled.
> 
> That goes back to what I stated first - there's nothing really requiring
> this, it just happens to be that way at present.

If you don't do this then the function doesn't work properly, so in that
sense it is a requirement! If you want it more explicit add a comment or
maybe even a BUG_ON().

 -- Keir



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