Re: [Qemu-devel] [Xen-devel] [PATCH 4/5] configure: detect presence of libxendevicemodel

[Paul Durrant <Paul.Durrant@citrix.com>]

> -----Original Message-----
> From: Juergen Gross [mailto:jgross@suse.com]
> Sent: 02 March 2017 11:01
> To: Anthony Perard <anthony.perard@citrix.com>; Paul Durrant
> <Paul.Durrant@citrix.com>
> Cc: xen-devel@lists.xenproject.org; Stefano Stabellini
> <sstabellini@kernel.org>; qemu-devel@nongnu.org
> Subject: Re: [Xen-devel] [PATCH 4/5] configure: detect presence of
> libxendevicemodel
> 
> On 02/03/17 11:54, Anthony PERARD wrote:
> > On Thu, Mar 02, 2017 at 09:06:43AM +0000, Paul Durrant wrote:
> >>> -----Original Message-----
> >>> From: Anthony PERARD [mailto:anthony.perard@citrix.com]
> >>> Sent: 01 March 2017 17:18
> >>> To: Paul Durrant <Paul.Durrant@citrix.com>
> >>> Cc: xen-devel@lists.xenproject.org; qemu-devel@nongnu.org; Stefano
> >>> Stabellini <sstabellini@kernel.org>
> >>> Subject: Re: [PATCH 4/5] configure: detect presence of
> libxendevicemodel
> >>>
> >>> On Thu, Feb 23, 2017 at 02:53:54PM +0000, Paul Durrant wrote:
> >>>> This patch adds code in configure to set
> >>> CONFIG_XEN_CTRL_INTERFACE_VERSION
> >>>> to a new value of 490 if libxendevicemodel is present in the build
> >>>> environment.
> >>>>
> >>>> Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
> >>>> ---
> >>>> Cc: Stefano Stabellini <sstabellini@kernel.org>
> >>>> Cc: Anthony Perard <anthony.perard@citrix.com>
> >>>> ---
> >>>>  configure | 19 +++++++++++++++++++
> >>>>  1 file changed, 19 insertions(+)
> >>>>
> >>>> diff --git a/configure b/configure
> >>>> index 8e8f18d..fc1e12b 100755
> >>>> --- a/configure
> >>>> +++ b/configure
> >>>> @@ -1980,6 +1980,25 @@ EOF
> >>>>    # Xen unstable
> >>>>    elif
> >>>>        cat > $TMPC <<EOF &&
> >>>> +#undef XC_WANT_COMPAT_DEVICEMODEL_API
> >>>> +#define __XEN_TOOLS__
> >>>
> >>> Isn't __XEN_TOOLS__ supposed to be reserved for some to tools inside
> >>> xen.git?
> >>>
> >>> Also it seems to be the only time this define is used in your patch
> >>> series.
> >>>
> >> No. QEMU falls under the definition of 'tools' as far as Xen goes and the
> hypercalls and xendevicemodel API are protected by that. The reason you
> don't see it elsewhere is that xenctrl.h defines it. (See
> http://xenbits.xen.org/gitweb/?p=xen.git;a=blob;f=tools/libxc/include/xenc
> trl.h;hb=HEAD#l27).
> >> I think that's a little underhand so I thought I'd make the new code in
> configure more transparent. I can change it to just include xenctrl.h before
> xendevicemodel.h if you'd prefer.
> >
> > I guess that is fine with __XEN_TOOLS__.
> > You can add my
> > Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
> >
> 
> Sorry for jumping in only now:
> 
> Wouldn't it be better to base qemu's configure modification for support
> of Xen 4.9 (and newer) on my just posted series introducing pkg-config?
> 
> I'm just about to expand this series to all of Xen's libraries and I
> already have a qemu patch at hand supporting this new scheme.

Ok, but I'm at v2 and I was literally just about to post. I guess it will also be pretty trivial to change configure after this change has been applied.

  Paul

> 
> 
> Juergen