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Re: [Xen-devel] [PATCH] Minor fix to xentop to stop it dying when domain

To: "Graham, Simon" <Simon.Graham@xxxxxxxxxxx>
Subject: Re: [Xen-devel] [PATCH] Minor fix to xentop to stop it dying when domains go away at the wrong time
From: Keir Fraser <Keir.Fraser@xxxxxxxxxxxx>
Date: Tue, 25 Jul 2006 19:48:42 +0100
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On 25 Jul 2006, at 19:40, Graham, Simon wrote:

1. It's not clear that all possible users of xenstat_get_node() would
   to have the call take an arbitrary amount of time as it struggles to
   get a consistent snapshot -- better to let the caller decide policy
   on retrying the call.

At the moment the caller cannot even make that choice as the function does not return specific error codes. If it, for example, returned a negative errno then the caller could check -EAGAIN. Anyhow, clearly the bulk of the patch belongs in libxenstat -- the only question is whether we retry internally or in the caller. I think the former is simpler as it does not change the function's specification.

 -- Keir

2. xentop is currently the only user of xenstat_get_node in the tree and
   fix in xentop was waaay easier ;-)

If you still think xenstat_get_node() should loop until it has a
consistent snapshot
then I'll redo the patch that way

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