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] ac_timer: time to say goodbye?

To: "Magenheimer, Dan (HP Labs Fort Collins)" <dan.magenheimer@xxxxxx>
Subject: Re: [Xen-devel] ac_timer: time to say goodbye?
From: Keir Fraser <Keir.Fraser@xxxxxxxxxxxx>
Date: Mon, 23 May 2005 21:48:10 +0100
Cc: xen-devel@xxxxxxxxxxxxxxxxxxx, Ian Pratt <Ian.Pratt@xxxxxxxxxxxx>
Delivery-date: Mon, 23 May 2005 20:50:46 +0000
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <516F50407E01324991DD6D07B0531AD542D07F@xxxxxxxxxxxxxxxxxxxxxxxxxxxxx>
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: <516F50407E01324991DD6D07B0531AD542D07F@xxxxxxxxxxxxxxxxxxxxxxxxxxxxx>
Sender: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx

On 23 May 2005, at 21:28, Magenheimer, Dan (HP Labs Fort Collins) wrote:

I suspect that the whole functionality of it can be replaced
with a couple of time variables that are checked and
manipulated in the timer interrupt code and a single
scheduler/timer routine in the generic scheduler.

We are going to strip out the periodic ticker entirely (at least in arch/x86) and have just a programmable one-shot timer. We need to keep track of what is the nearest event we care about so we know what to program into the one-shot timer.

I think the interface could be simplified a little (fold mod_ac_timer/add_ac_timer into a single function, for example), but the implementation is already very pared down. I image it would hardly save 100 lines, or bytes of hypervisor code, to replace the heap with a list, for example.

 -- Keir


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

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