From mboxrd@z Thu Jan  1 00:00:00 1970
From: Wei Liu <wei.liu2@citrix.com>
Subject: Re: [PATCH v1 03/10] libxl: store a copy of vanilla
 domain configuration when creating domain
Date: Wed, 16 Jul 2014 17:47:30 +0100
Message-ID: <20140716164730.GC4913@zion.uk.xensource.com>
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To: Ian Campbell <Ian.Campbell@citrix.com>
Cc: ian.jackson@eu.citrix.com, Wei Liu <wei.liu2@citrix.com>, xen-devel@lists.xen.org
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On Wed, Jul 16, 2014 at 05:18:08PM +0100, Ian Campbell wrote:
> On Thu, 2014-07-10 at 15:32 +0100, Wei Liu wrote:
> 
> > +/* update the saved domain configuration with a callback function,
> > + * which is responsible to pull in useful fields from src.
> > + */
> > +typedef void (update_callback)(libxl__gc *, libxl_domain_config *,
> > +                               const libxl_domain_config *);
> > +static int libxl__update_domain_configuration(libxl__gc *gc,
> > +                                              uint32_t domid,
> > +                                              update_callback callback,
> > +                                              const libxl_domain_config *src)
> 
> You aren't using your shiny new locking functions here?
> 

We don't need locking here. The lock should already be held (if it needs
to be held).

Note, this is not async callback, this is just to make it possible to
replace the update function at will. Probably renaming "update_callback"
to "update" is better?

And for larger scope, when creating a domain, there shouldn't be any
other thread trying to access the configuration file (is there?), so
locking is not necessary.

Wei.