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


Re: [Xen-devel] xhci passthrough

To: Sander Eikelenboom <linux@xxxxxxxxxxxxxx>
Subject: Re: [Xen-devel] xhci passthrough
From: Konrad Rzeszutek Wilk <konrad.wilk@xxxxxxxxxx>
Date: Thu, 28 Oct 2010 17:12:23 -0400
Cc: Jeremy Fitzhardinge <jeremy@xxxxxxxx>, "Xen-devel@xxxxxxxxxxxxxxxxxxx" <Xen-devel@xxxxxxxxxxxxxxxxxxx>
Delivery-date: Thu, 28 Oct 2010 14:13:23 -0700
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <2010169160.20101028000118@xxxxxxxxxxxxxx>
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: <2010169160.20101028000118@xxxxxxxxxxxxxx>
Sender: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
User-agent: Mutt/1.5.20 (2009-06-14)
On Thu, Oct 28, 2010 at 12:01:18AM +0200, Sander Eikelenboom wrote:
> Hi Konrad,
> Due to a 2.6.37-merge-window kernel now being able to boot under Xen i was 
> able to test my xhci controller under dom0 which i previously couldn't.
> The results:
> A) 2.6.37-merge-window kernel baremetal: Videograbbing while doing 20 
> iterations of make -j6 of kernel works.
> B) Xen + 2.6.37-merge-window kernel as Dom0: Videograbbing while doing 20 
> iterations of make -j6 of kernel works.

> C) Xen + pvops dom0 +  2.6.37-merge-window kernel DomU: 
> Videograbbing while doing 20 iterations of make -j6  still freezes the 
> machine without a trace after a short while.

Ok, so it points to the doing something funky, which unfortunatly  
does not help that much
as the xen patches that are in the 2.6.37-merge-window for IRQ are about the 
as what has. Thought the 2.6.37-merge-window got tons of bells and 
whistles in the
generic Linux kernel code part.

These interrupts were for the MSI-X for the XHCI controller or was it legacy 

> An other interesting thing is the interrupt rate i see in /proc/interrrupts 
> for the xhci controller, i measured for 5 minutes each time.
> In situation:
> A) About 3200 Interrupts/second
> B) About 3200 Interrupts/second
> C) About 7800 Interrupts/second, what would be 7.8 interrupt per ms which 
> seems to work as long as you don't stress the rest to the limit.
>    Which probably causes some sort of deadlock (some where in the path from 
> device, xen, dom0/pciback , domU/pcifront, xhci driver, application.) when 
> not delivered on time or when it boldly goes on a code path where no one has 
> gone before ..
> Compared with a measurement of interrupts by a USB2 controller:
> Around 155 Interrupts/second
> Probably a silly question without a right answer ... but what interrupt rate 
> would you guess it should be able to take ?
> And is it logically that when passed through it causes around 2.5 times more 
> interrupts ?
> Now testing on a Intel(R) Core(TM)2 Quad CPU    Q9400  @ 2.66GHz
> --
> Sander
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@xxxxxxxxxxxxxxxxxxx
> http://lists.xensource.com/xen-devel

Xen-devel mailing list

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