From mboxrd@z Thu Jan  1 00:00:00 1970
From: Dario Faggioli <dario.faggioli@citrix.com>
Subject: Re: [PATCH v6 01/10] xen: vnuma topology and subop
 hypercalls
Date: Tue, 22 Jul 2014 17:18:07 +0200
Message-ID: <1406042287.17850.78.camel@Solace>
References: <1405662609-31486-1-git-send-email-ufimtseva@gmail.com>
	<1405662609-31486-2-git-send-email-ufimtseva@gmail.com>
	<20140718103034.GA7142@zion.uk.xensource.com>
	<CAEr7rXifuLnHECG6pCBThgRwzv2K92pSgRaPp95m51Y+GoVSpw@mail.gmail.com>
	<20140720155918.GB26184@zion.uk.xensource.com>
Mime-Version: 1.0
Content-Type: multipart/mixed; boundary="===============0878592220935533030=="
Return-path: <xen-devel-bounces@lists.xen.org>
In-Reply-To: <20140720155918.GB26184@zion.uk.xensource.com>
List-Unsubscribe: <http://lists.xen.org/cgi-bin/mailman/options/xen-devel>,
	<mailto:xen-devel-request@lists.xen.org?subject=unsubscribe>
List-Post: <mailto:xen-devel@lists.xen.org>
List-Help: <mailto:xen-devel-request@lists.xen.org?subject=help>
List-Subscribe: <http://lists.xen.org/cgi-bin/mailman/listinfo/xen-devel>,
	<mailto:xen-devel-request@lists.xen.org?subject=subscribe>
Sender: xen-devel-bounces@lists.xen.org
Errors-To: xen-devel-bounces@lists.xen.org
To: Wei Liu <wei.liu2@citrix.com>
Cc: Keir Fraser <keir@xen.org>, Ian Campbell <Ian.Campbell@citrix.com>, Stefano Stabellini <stefano.stabellini@eu.citrix.com>, George Dunlap <george.dunlap@eu.citrix.com>, Matt Wilson <msw@linux.com>, Li Yechen <lccycc123@gmail.com>, Ian Jackson <ian.jackson@eu.citrix.com>, "xen-devel@lists.xen.org" <xen-devel@lists.xen.org>, Jan Beulich <JBeulich@suse.com>, Elena Ufimtseva <ufimtseva@gmail.com>
List-Id: xen-devel@lists.xenproject.org

--===============0878592220935533030==
Content-Type: multipart/signed; micalg=pgp-sha1;
	protocol="application/pgp-signature"; boundary="=-k8rid5FgTEwLDGNRvzzD"

--=-k8rid5FgTEwLDGNRvzzD
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable

On dom, 2014-07-20 at 16:59 +0100, Wei Liu wrote:
> On Sun, Jul 20, 2014 at 09:16:11AM -0400, Elena Ufimtseva wrote:

> > >> +struct vnuma_topology_info {
> > >> +    /* IN */
> > >> +    domid_t domid;
> > >> +    /* IN/OUT */
> > >> +    unsigned int nr_vnodes;
> > >> +    unsigned int nr_vcpus;
> > >> +    /* OUT */
> > >> +    union {
> > >> +        XEN_GUEST_HANDLE(uint) h;
> > >> +        uint64_t pad;
> > >> +    } vdistance;
> > >> +    union {
> > >> +        XEN_GUEST_HANDLE(uint) h;
> > >> +        uint64_t pad;
> > >> +    } vcpu_to_vnode;
> > >> +    union {
> > >> +        XEN_GUEST_HANDLE(vmemrange_t) h;
> > >> +        uint64_t pad;
> > >> +    } vmemrange;
> > >
> > > Why do you need to use union? The other interface you introduce in th=
is
> > > patch doesn't use union.
> >=20
> > This is one is for making sure on 32 and 64 bits the structures are of
> > the same size.
> >=20
>=20
> I can see other similiar occurences of XEN_GUEST_HANDLE don't need
> padding. Did I miss something?
>=20
I remember this coming up during review of an earlier version of Elena's
series, and I think I also remember the union with padding solution
being suggested, but I don't remember which round it was, and who
suggested it... Elena, up for some digging in your inbox (or xen-devel
archives)? :-P

Regards,
Dario

--=20
<<This happens because I choose it to happen!>> (Raistlin Majere)
-----------------------------------------------------------------
Dario Faggioli, Ph.D, http://about.me/dario.faggioli
Senior Software Engineer, Citrix Systems R&D Ltd., Cambridge (UK)


--=-k8rid5FgTEwLDGNRvzzD
Content-Type: application/pgp-signature; name="signature.asc"
Content-Description: This is a digitally signed message part
Content-Transfer-Encoding: 7bit

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2

iEYEABECAAYFAlPOgK8ACgkQk4XaBE3IOsR30ACfeJnpT3RjKgwO4kUpYePPrpYE
LVUAoIkYKe/0hGy7gmb0NCRZfjI0zun3
=ExvZ
-----END PGP SIGNATURE-----

--=-k8rid5FgTEwLDGNRvzzD--


--===============0878592220935533030==
Content-Type: text/plain; charset="us-ascii"
MIME-Version: 1.0
Content-Transfer-Encoding: 7bit
Content-Disposition: inline

_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
http://lists.xen.org/xen-devel

--===============0878592220935533030==--