From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:33769) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZgwNR-0005nj-41 for qemu-devel@nongnu.org; Tue, 29 Sep 2015 10:59:34 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZgwNO-0000RW-DH for qemu-devel@nongnu.org; Tue, 29 Sep 2015 10:59:33 -0400 Received: from mx1.redhat.com ([209.132.183.28]:43454) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZgwNO-0000RH-5w for qemu-devel@nongnu.org; Tue, 29 Sep 2015 10:59:30 -0400 Date: Tue, 29 Sep 2015 17:59:24 +0300 From: "Michael S. Tsirkin" Message-ID: <20150929175849-mutt-send-email-mst@redhat.com> References: <1443111741-4736-1-git-send-email-marcandre.lureau@redhat.com> <1443111741-4736-12-git-send-email-marcandre.lureau@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline In-Reply-To: <1443111741-4736-12-git-send-email-marcandre.lureau@redhat.com> Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [PATCH v5 11/21] vhost: only use shared log if in use by backend List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: marcandre.lureau@redhat.com Cc: haifeng.lin@huawei.com, thibaut.collet@6wind.com, jasowang@redhat.com, qemu-devel@nongnu.org, pbonzini@redhat.com On Thu, Sep 24, 2015 at 06:22:11PM +0200, marcandre.lureau@redhat.com wro= te: > From: Marc-Andr=E9 Lureau >=20 > Do not allocate a shared log if the backend doesn't support it. >=20 > Signed-off-by: Marc-Andr=E9 Lureau So squash this in the previous patch introducing the shared log? This split makes review harder, not easier. > --- > hw/virtio/vhost-user.c | 9 +++++++++ > hw/virtio/vhost.c | 15 ++++++++++----- > include/hw/virtio/vhost-backend.h | 4 ++++ > 3 files changed, 23 insertions(+), 5 deletions(-) >=20 > diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c > index 41e0364..455caba 100644 > --- a/hw/virtio/vhost-user.c > +++ b/hw/virtio/vhost-user.c > @@ -553,6 +553,14 @@ static int vhost_user_get_vq_index(struct vhost_de= v *dev, int idx) > return idx; > } > =20 > +static bool vhost_user_requires_shm_log(struct vhost_dev *dev) > +{ > + assert(dev->vhost_ops->backend_type =3D=3D VHOST_BACKEND_TYPE_USER= ); > + > + return virtio_has_feature(dev->protocol_features, > + VHOST_USER_PROTOCOL_F_LOG_SHMFD); > +} > + > const VhostOps user_ops =3D { > .backend_type =3D VHOST_BACKEND_TYPE_USER, > .vhost_backend_init =3D vhost_user_init, > @@ -573,4 +581,5 @@ const VhostOps user_ops =3D { > .vhost_reset_device =3D vhost_user_reset_device, > .vhost_get_vq_index =3D vhost_user_get_vq_index, > .vhost_set_vring_enable =3D vhost_user_set_vring_enable, > + .vhost_requires_shm_log =3D vhost_user_requires_shm_log, > }; > diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c > index d9f2131..ec27c7b 100644 > --- a/hw/virtio/vhost.c > +++ b/hw/virtio/vhost.c > @@ -357,10 +357,15 @@ static void vhost_log_put(struct vhost_dev *dev, = bool sync) > } > } > =20 > -static inline void vhost_dev_log_resize(struct vhost_dev* dev, uint64_= t size) > +static bool vhost_dev_log_is_shared(struct vhost_dev *dev) > { > - bool share =3D dev->vhost_ops->backend_type =3D=3D VHOST_BACKEND_T= YPE_USER; > - struct vhost_log *log =3D vhost_log_get(size, share); > + return dev->vhost_ops->vhost_requires_shm_log && > + dev->vhost_ops->vhost_requires_shm_log(dev); > +} > + > +static inline void vhost_dev_log_resize(struct vhost_dev *dev, uint64_= t size) > +{ > + struct vhost_log *log =3D vhost_log_get(size, vhost_dev_log_is_sha= red(dev)); > uint64_t log_base =3D (uintptr_t)log->log; > int r; > =20 > @@ -1166,10 +1171,10 @@ int vhost_dev_start(struct vhost_dev *hdev, Vir= tIODevice *vdev) > =20 > if (hdev->log_enabled) { > uint64_t log_base; > - bool share =3D hdev->vhost_ops->backend_type =3D=3D VHOST_BACK= END_TYPE_USER; > =20 > hdev->log_size =3D vhost_get_log_size(hdev); > - hdev->log =3D vhost_log_get(hdev->log_size, share); > + hdev->log =3D vhost_log_get(hdev->log_size, > + vhost_dev_log_is_shared(hdev)); > log_base =3D (uintptr_t)hdev->log->log; > r =3D hdev->vhost_ops->vhost_set_log_base(hdev, > hdev->log_size ? log_b= ase : 0, > diff --git a/include/hw/virtio/vhost-backend.h b/include/hw/virtio/vhos= t-backend.h > index 868a78a..e07118c 100644 > --- a/include/hw/virtio/vhost-backend.h > +++ b/include/hw/virtio/vhost-backend.h > @@ -11,6 +11,8 @@ > #ifndef VHOST_BACKEND_H_ > #define VHOST_BACKEND_H_ > =20 > +#include > + > typedef enum VhostBackendType { > VHOST_BACKEND_TYPE_NONE =3D 0, > VHOST_BACKEND_TYPE_KERNEL =3D 1, > @@ -64,6 +66,7 @@ typedef int (*vhost_reset_device_op)(struct vhost_dev= *dev); > typedef int (*vhost_get_vq_index_op)(struct vhost_dev *dev, int idx); > typedef int (*vhost_set_vring_enable_op)(struct vhost_dev *dev, > int enable); > +typedef bool (*vhost_requires_shm_log_op)(struct vhost_dev *dev); > =20 > typedef struct VhostOps { > VhostBackendType backend_type; > @@ -90,6 +93,7 @@ typedef struct VhostOps { > vhost_reset_device_op vhost_reset_device; > vhost_get_vq_index_op vhost_get_vq_index; > vhost_set_vring_enable_op vhost_set_vring_enable; > + vhost_requires_shm_log_op vhost_requires_shm_log; > } VhostOps; > =20 > extern const VhostOps user_ops; > --=20 > 2.4.3