From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jan Kiszka Subject: Re: [RFC][PATCH 11/45] msi: Factor out delivery hook Date: Mon, 17 Oct 2011 21:18:01 +0200 Message-ID: <4E9C7F69.5080606@web.de> References: <4E9C09E7.2010106@redhat.com> <4E9C0E6C.2070809@siemens.com> <20111017134135.GC6406@redhat.com> <4E9C3098.4080804@redhat.com> <20111017134814.GE6406@redhat.com> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enigDAFF1E24786854877967C4CD" Cc: Alex Williamson , Marcelo Tosatti , Avi Kivity , "kvm@vger.kernel.org" , "qemu-devel@nongnu.org" To: "Michael S. Tsirkin" Return-path: In-Reply-To: <20111017134814.GE6406@redhat.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+gceq-qemu-devel=gmane.org@nongnu.org Sender: qemu-devel-bounces+gceq-qemu-devel=gmane.org@nongnu.org List-Id: kvm.vger.kernel.org This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enigDAFF1E24786854877967C4CD Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable On 2011-10-17 15:48, Michael S. Tsirkin wrote: > On Mon, Oct 17, 2011 at 03:41:44PM +0200, Avi Kivity wrote: >> On 10/17/2011 03:41 PM, Michael S. Tsirkin wrote: >>> On Mon, Oct 17, 2011 at 01:15:56PM +0200, Jan Kiszka wrote: >>>> On 2011-10-17 12:56, Avi Kivity wrote: >>>>> On 10/17/2011 11:27 AM, Jan Kiszka wrote: >>>>>> So far we deliver MSI messages by writing them into the target MMI= O >>>>>> area. This reflects what happens on hardware, but imposes some >>>>>> limitations on the emulation when introducing KVM in-kernel irqchi= p >>>>>> models. For those we will need to track the message origin. >>>>> >>>>> Why do we need to track the message origin? Emulated interrupt rem= apping? >>>> >>>> The origin holds the routing cache which we need to track if the mes= sage >>>> already has a route (and that without searching long lists) and to >>>> update that route instead of add another one. >>> >>> Hmm, yes, but if the device does stl_phys or something like this, >>> it won't work with irqchip, will it? And it should, ideally. >> >> Why not? it will fall back to the apic path, and use the local routin= g >> cache entry there. >=20 > Does it still work with irqchip enabled? I didn't realize ... Yep, as MSI requests that land in the APIC MMIO page are also fed into msi_deliver and will take the normal path from there on. Jan --------------enigDAFF1E24786854877967C4CD Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.16 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iEYEARECAAYFAk6cf2kACgkQitSsb3rl5xTrcQCgzWEqRXViH7gi3JmTyV5fuOs6 ol4An2wzAEkhQU+M59fxY5MrKCQYL+Ne =F89L -----END PGP SIGNATURE----- --------------enigDAFF1E24786854877967C4CD--