From mboxrd@z Thu Jan  1 00:00:00 1970
From: Julien Grall <julien.grall@linaro.org>
Subject: Re: [PATCH for-4.5 7/8] xen/irq: Handle multiple action
 per IRQ
Date: Wed, 19 Feb 2014 14:41:48 +0000
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To: Ian Campbell <Ian.Campbell@citrix.com>
Cc: xen-devel@lists.xenproject.org, tim@xen.org, Keir Fraser <keir@xen.org>, stefano.stabellini@citrix.com, patches@linaro.org
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Hi Ian,

On 02/19/2014 11:55 AM, Ian Campbell wrote:
> On Fri, 2014-01-24 at 16:43 +0000, Julien Grall wrote:
>> On ARM, it may happen (eg ARM SMMU) to setup multiple handler for the same
>> interrupt.
> 
> Mention here that you are therefore creating a linked list of actions
> for each interrupt.
> 
> If you use xen/list.h for this then you get a load of helpers and
> iterators which would save you open coding them.

I will use it on the next version.

> Some discussion of the behaviour wrt acking the physical interrupt might
> also be interesting, especially in the case where the shared IRQ is
> routed to the guest and to the hypervisor or to multiple guests.

For now, it's forbidden by the patch #3 of this series. Sharing IRQ
between Xen and guest will need a bit of rework, mainly when the
Stefano's patch series to remove the maintenance interrupt will be applied.

Cheers,

-- 
Julien Grall