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

[Xen-devel] Re: [GIT PATCH v2 0/14] xen: events: cleanups + ween off nr_

To: Konrad Rzeszutek Wilk <konrad.wilk@xxxxxxxxxx>
Subject: [Xen-devel] Re: [GIT PATCH v2 0/14] xen: events: cleanups + ween off nr_irqs
From: Ian Campbell <Ian.Campbell@xxxxxxxxxxxxx>
Date: Fri, 11 Mar 2011 09:12:54 +0000
Cc: Fitzhardinge <jeremy@xxxxxxxx>, "xen-devel@xxxxxxxxxxxxxxxxxxx" <xen-devel@xxxxxxxxxxxxxxxxxxx>, Jeremy, "linux-kernel@xxxxxxxxxxxxxxx" <linux-kernel@xxxxxxxxxxxxxxx>, Stefano Stabellini <Stefano.Stabellini@xxxxxxxxxxxxx>
Delivery-date: Fri, 11 Mar 2011 01:13:33 -0800
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <20110310225726.GA2983@xxxxxxxxxxxx>
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>
Organization: Citrix Systems, Inc.
References: <1299773279.17339.813.camel@xxxxxxxxxxxxxxxxxxxxxx> <20110310225726.GA2983@xxxxxxxxxxxx>
Sender: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
On Thu, 2011-03-10 at 22:57 +0000, Konrad Rzeszutek Wilk wrote:
> On Thu, Mar 10, 2011 at 04:07:59PM +0000, Ian Campbell wrote:
> > Changes since last time:
> >       * correct return value of xen_irq_from_pirq
> >       * WARN if a pirq cannot be allocated for a legacy IRQ
> >       * Updated checking comment of "xen: events: do not workaround
> >         too-small nr_irqs"
> > 
> > The following series makes a few cleanups to the Xen IRQ infrastructure.
> > The most important thing is that it removes the need to know about
> > nr_irqs and in particular the reliance on nr_irqs being static.
> > 
> > Apart from being generally a good thing this is needed because in 2.6.39
> > nr_irqs will be able to grow dynamically, specifically e7bcecb7b1d2
> > "genirq: Make nr_irqs runtime expandable" from tip/core/irq is targeted
> > at 2.6.39.
> > 
> > Dynamically growing nr_irqs also allows us to remove the workaround
> > which eats into GSI space if a dynamic IRQ cannot be allocated.
> > 
> > There is no ideal sequencing of this series vs e7bcecb7b1d2 (most should
> > have gone in before, but the penultimate patch really needed to be
> > simultaneous) so I haven't bothered to try and pull anything from tip
> > into this branch -- it should all be resolved during the merge window
> > and bisection won't be too broken since the "eat into GSI space"
> > workaround only appears to be needed on a small number of older
> > platforms (qemu being the main exception).
> 
> <nods>
> > 
> > I have tested:
> >       * Domain 0 on real h/w and under qemu
> >       * PV guest, including migration and passthrough of both VF and PF.
> >       * PVHVM guest, including migration and passthrough of both VF and
> >         PF.
> 
> I am having difficulties with passthrough of an USB device. Somehow the
> irq count is not going up at all (both in dom0 and domU) and it looks to
> be doing just simple polling. I've rebased the xen-pciback to be on top
> of your changes and apply cleanly. The whole lot is now in #master
> 
> MSI and MSI-X devices work just fine in both Dom0 and DomU case so
> it is something special with the legacy IRQs. Probably forgot something
> simple...

Thanks, I'll take a look. Did you mean "legacy IRQ" as in <16 or as in
not-MSI(-X)?

Ian.


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

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