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Date: Sun, 28 Jul 2024 19:11:32 +0530 Message-ID: <2751519.mvXUDI8C0e@valdaarhun> In-Reply-To: References: <20240726095822.104017-1-sahilcdq@proton.me> <20240726095822.104017-4-sahilcdq@proton.me> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Received-SPF: pass client-ip=2607:f8b0:4864:20::432; envelope-from=icegambit91@gmail.com; helo=mail-pf1-x432.google.com X-Spam_score_int: 15 X-Spam_score: 1.5 X-Spam_bar: + X-Spam_report: (1.5 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, FREEMAIL_ENVFROM_END_DIGIT=0.25, FREEMAIL_FROM=0.001, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_SBL_CSS=3.335, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=no autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Hi, On Friday, July 26, 2024 7:58:49=E2=80=AFPM GMT+5:30 Eugenio Perez Martin w= rote: > On Fri, Jul 26, 2024 at 11:59=E2=80=AFAM Sahil Siddiq wrote: > > [...] > > @@ -759,19 +780,34 @@ void vhost_svq_start(VhostShadowVirtqueue *svq, > > VirtIODevice *vdev,>=20 > > svq->vq =3D vq; > > svq->iova_tree =3D iova_tree; > >=20 > > - svq->vring.num =3D virtio_queue_get_num(vdev, > > virtio_get_queue_index(vq)); - svq->num_free =3D svq->vring.num; > > - svq->vring.desc =3D mmap(NULL, vhost_svq_driver_area_size(svq), > > - PROT_READ | PROT_WRITE, MAP_SHARED | > > MAP_ANONYMOUS, - -1, 0); > > - desc_size =3D sizeof(vring_desc_t) * svq->vring.num; > > - svq->vring.avail =3D (void *)((char *)svq->vring.desc + desc_size); > > - svq->vring.used =3D mmap(NULL, vhost_svq_device_area_size(svq), > > - PROT_READ | PROT_WRITE, MAP_SHARED | > > MAP_ANONYMOUS, - -1, 0); > > - svq->desc_state =3D g_new0(SVQDescState, svq->vring.num); > > - svq->desc_next =3D g_new0(uint16_t, svq->vring.num); > > - for (unsigned i =3D 0; i < svq->vring.num - 1; i++) { > > + if (virtio_vdev_has_feature(svq->vdev, VIRTIO_F_RING_PACKED)) { > > + svq->is_packed =3D true; > > + svq->vring_packed.vring.num =3D virtio_queue_get_num(vdev, > > virtio_get_queue_index(vq)); + svq->num_free =3D > > svq->vring_packed.vring.num; > > + svq->vring_packed.vring.desc =3D mmap(NULL, > > vhost_svq_memory_packed(svq), + = =20 > > PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, + = =20 > > -1, 0); > > + desc_size =3D sizeof(struct vring_packed_desc) * svq->vring.nu= m; > > + svq->vring_packed.vring.driver =3D (void *)((char > > *)svq->vring_packed.vring.desc + desc_size); > (Expanding on the cover letter comment) Here the driver area is > aligned properly too as each descriptor is 16 bytes length, and > required alignment for the driver area is 4 bytes by VirtIO standard. Ok, this makes sense now. > > + svq->vring_packed.vring.device =3D (void *)((char *)svq- >vring_packed.vring.driver + > > + sizeof(struct vring_packed_desc_e= vent)); + } else { > > + svq->is_packed =3D false; > > + svq->vring.num =3D virtio_queue_get_num(vdev, virtio_get_queue= _index(vq)); > > + svq->num_free =3D svq->vring.num; >=20 > Nitpicks, >=20 > The variables is_packed and num_free can be merged out of the if/else > to reduce code duplication. >=20 > Also it is clearer to me to assign svq->is_packed =3D > virtio_vdev_has_feature(...) and then check the variable in the if. > But other parts of QEMU do as you do here so I don't have a strong > opinion. I think your suggestion will reduce code duplication. I'll change this. > > [...] > > @@ -146,10 +149,13 @@ size_t vhost_svq_poll(VhostShadowVirtqueue *svq, = size_t num); > >=20 > > void vhost_svq_set_svq_kick_fd(VhostShadowVirtqueue *svq, int svq_kick= _fd); > > void vhost_svq_set_svq_call_fd(VhostShadowVirtqueue *svq, int call_fd); > > -void vhost_svq_get_vring_addr(const VhostShadowVirtqueue *svq, > > - struct vhost_vring_addr *addr); > > +void vhost_svq_get_vring_addr_split(const VhostShadowVirtqueue *svq, > > + struct vhost_vring_addr *addr); > > +void vhost_svq_get_vring_addr_packed(const VhostShadowVirtqueue *svq, > > + struct vhost_vring_addr *addr); > >=20 > > size_t vhost_svq_driver_area_size(const VhostShadowVirtqueue *svq); > > size_t vhost_svq_device_area_size(const VhostShadowVirtqueue *svq); > >=20 > > +size_t vhost_svq_memory_packed(const VhostShadowVirtqueue *svq); >=20 > Ok now I get the question on the cover letter better, >=20 > It is ok to reuse the already present functions, no need to create new > ones to export in this header. I think "vhost_svq_memory_packed" will be required while the others can be removed. Thanks, Sahil