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Re: [Xen-devel] [PATCH] xc_save: ignore the first suspend event channel

To: Brendan Cully <brendan@xxxxxxxxx>
Subject: Re: [Xen-devel] [PATCH] xc_save: ignore the first suspend event channel notification
From: Keir Fraser <keir.fraser@xxxxxxxxxxxxx>
Date: Sun, 07 Sep 2008 08:11:32 +0100
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On 7/9/08 08:06, "Keir Fraser" <keir.fraser@xxxxxxxxxxxxx> wrote:

>> I could certainly code this up as well (it'd need a static flag in
>> evtchn_suspend as well to avoid resignalling the domain, I think). But
>> generally without clearing the event channel before signalling the
>> guest, the first suspend attempt will always return early. I'm not
>> really clear on the scenario that results in the domain not being
>> suspended after *suspend has succesfully returned. Could you clarify?
> I don't like the forced initial consumption of a single evtchn signal. I'd
> like rid of that and change the retry loop to call (*suspend) instead. Add
> an extra boolean to the static suspend_info structure to detect first
> invocation of (*suspend) versus repeated invocations.

Actually I can knock these changes together myself, so I'll do that, taking
whatever bits of your patch are appropriate.

 -- Keir

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