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: 4.0/4.1 requests - IO-APIC EOI v4 [RFC]

To: Jan Beulich <JBeulich@xxxxxxxx>, Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
Subject: Re: [Xen-devel] Re: 4.0/4.1 requests - IO-APIC EOI v4 [RFC]
From: Keir Fraser <keir.xen@xxxxxxxxx>
Date: Mon, 12 Sep 2011 12:30:54 +0100
Cc: "xen-devel@xxxxxxxxxxxxxxxxxxx" <xen-devel@xxxxxxxxxxxxxxxxxxx>
Delivery-date: Mon, 12 Sep 2011 04:31:57 -0700
Dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=user-agent:date:subject:from:to:cc:message-id:thread-topic :thread-index:in-reply-to:mime-version:content-type :content-transfer-encoding; bh=3Ryw2g0/sZl1I67wzC9qTp2b1daMJTRiBixIINwkfS8=; b=AqIIeZSiB5NvtCcSgIIwW1oNNgLcmtgyDOu+vp2Zkj981pepq2lXsJ+jiQZ0lgtnKU hTKjZBl2kWKNrln9UgWMGNXmHl5Eg+4A0ehrOuJ3DwRAt0fBRDIcHkjnirw+m9Y9KpP0 lLSoJPgXaa/LrL2UaoRX1KMmMfN4UDqPQv3Y4=
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <4E6DF9AB0200007800055B2F@xxxxxxxxxxxxxxxxxxxx>
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: AcxxP26jSANcPtfEZ0qJP1OmRs/uww==
Thread-topic: [Xen-devel] Re: 4.0/4.1 requests - IO-APIC EOI v4 [RFC]
User-agent: Microsoft-Entourage/12.30.0.110427
On 12/09/2011 11:23, "Jan Beulich" <JBeulich@xxxxxxxx> wrote:

>>>> On 12.09.11 at 12:15, Andrew Cooper <andrew.cooper3@xxxxxxxxxx> wrote:
>> On 12/09/11 07:50, Jan Beulich wrote:
>>>>>> On 09.09.11 at 18:47, Andrew Cooper <andrew.cooper3@xxxxxxxxxx> wrote:
>>>> +                     * Xen code doesn't actually prevent multiple IO-APIC
>>>> +                     * entries being assigned the same vector, so EOI all
>>>> +                     * pins which have the correct vector.
>>>> +                     *
>>>> +                     * Remove the following code when the above assertion
>>>> +                     * is fulfilled. */
>>>> +
>>> Why don't you just call __io_apic_eoi() recursively here?
>>> 
>>> Jan
>> 
>> If I call the function recursively, it will loop forever.  Anyway, the
> 
> Why would it loop forever? You get in here only with pin == -1, and
> for the recursive call you'd pass the pin number you determined.

Exactly. Please re-send the patch with the recursive call. It makes the
function quite a bit shorter.

 -- Keir

>> need to clear multiple pins is only temorary until George finishes his
>> per-device AMD interrupt remap patch which will enforce vector
>> uniqueness in each IO-APIC.  My expectation is that this issue will be
>> fixed in the next few weeks.
> 
> Sure.
> 
> Jan
> 



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