Re: [Xen-devel] [PATCH v4 1/7] libxl: add definition of INVALID_DOMID to the API

["Durrant, Paul" <pdurrant@xxxxxxxxxxxx>]

> -----Original Message-----
> From: Xen-devel <xen-devel-bounces@xxxxxxxxxxxxxxxxxxxx> On Behalf Of
> Roger Pau Monné
> Sent: 22 January 2020 14:53
> To: Durrant, Paul <pdurrant@xxxxxxxxxxxx>
> Cc: Anthony PERARD <anthony.perard@xxxxxxxxxx>; xen-
> devel@xxxxxxxxxxxxxxxxxxxx; Ian Jackson <ian.jackson@xxxxxxxxxxxxx>; Wei
> Liu <wl@xxxxxxx>
> Subject: Re: [Xen-devel] [PATCH v4 1/7] libxl: add definition of
> INVALID_DOMID to the API
> 
> On Wed, Jan 22, 2020 at 02:44:40PM +0000, Paul Durrant wrote:
> > Currently both xl and libxl have internal definitions of INVALID_DOMID
> > which happen to be identical. However, for the purposes of describing
> the
> > behaviour of libxl_domain_create_new/restore() it is useful to have a
> > specified invalid value for a domain id.
> >
> > This patch therefore moves the libxl definition from libxl_internal.h to
> > libxl.h and removes the internal definition from xl_utils.h. The
> hardcoded
> > '-1' passed back via domcreate_complete() is then updated to
> INVALID_DOMID
> > and comment above libxl_domain_create_new/restore() is accordingly
> > modified.
> 
> Urg, it's kind of ugly to add another definition of invalid domid when
> there's already DOMID_INVALID in the public headers. I guess there's a
> reason I'm missing for not using DOMID_INVALID instead of introducing
> a new value?
> 

TBH I don't know. As far as xl/libxl goes, domids are uint32_ts so maybe 
DOMID_INVALID was for some reason not considered appropriate? Bear in mind, 
this patch is not truly introducing a new value; it's just making something 
that was internal but identical in both xl and libxl part of the interface.

> If so could this be mentioned in the commit message?
> 

I'll add a note to the commit comment to point out that this is not changing 
any value used by the toolstack.

  Paul

> Thanks, Roger.
> 
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@xxxxxxxxxxxxxxxxxxxx
> https://lists.xenproject.org/mailman/listinfo/xen-devel
_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/xen-devel