From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:42473) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fQHJW-0001wi-4I for qemu-devel@nongnu.org; Tue, 05 Jun 2018 15:08:15 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fQHJU-0002x4-Rv for qemu-devel@nongnu.org; Tue, 05 Jun 2018 15:08:14 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:50264 helo=mx1.redhat.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1fQHJU-0002vn-Kz for qemu-devel@nongnu.org; Tue, 05 Jun 2018 15:08:12 -0400 From: wexu@redhat.com Date: Tue, 5 Jun 2018 15:07:55 -0400 Message-Id: <1528225683-11413-1-git-send-email-wexu@redhat.com> Subject: [Qemu-devel] [RFC v2 0/8] packed ring virtio-net userspace backend support List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: jasowang@redhat.com, tiwei.bie@intel.com, mst@redhat.com, wexu@redhat.com, jfreimann@redhat.com From: Wei Xu Todo: - address Rx slow performance - event index interrupt suppression test v1->v2 - sync to tiwei's v5 - reuse memory cache function with 1.0 - dropped detach patch and notification helper(04 & 05 in v1) - guest virtio-net driver unload/reload support - event suppression support(not tested) - addressed feedback from v1 About guest virtio-net load/unload: Since last_avail, avail_wrap_count, used_idx and used_wrap_count are all 16 or bool type variables, so I turned to merge them to 'vhost_vring_state.num' in stead of introducing a new case in handling ioctl, test has been done with a tweak in kernel side like: --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -1439,10 +1439,16 @@ long vhost_vring_ioctl(struct vhost_dev *d, int ioctl, void __user *argp) r = -EFAULT; break; } - if (s.num > 0xffff) { - r = -EINVAL; - break; - } + if (vhost_has_feature(vq, VIRTIO_F_RING_PACKED)) { + vq->avail_wrap_counter = (bool)(uint16_t)(s.num >> 16); + vq->last_used_idx = (uint16_t)(s.num >> 32); + vq->used_wrap_counter = (bool)(uint16_t)(s.num >> 48); + } else { + if (s.num > 0xffff) { + r = -EINVAL; + break; + } + } vq->last_avail_idx = s.num; /* Forget the cached index value. */ vq->avail_idx = vq->last_avail_idx; @@ -1450,8 +1456,15 @@ long vhost_vring_ioctl(struct vhost_dev *d, int ioctl, void __user *argp) case VHOST_GET_VRING_BASE: s.index = idx; s.num = vq->last_avail_idx; + if (vhost_has_feature(vq, VIRTIO_F_RING_PACKED)) { + s.num |= vq->avail_wrap_counter << 16; + s.num |= vq->last_used_idx << 32; + s.num |= vq->used_wrap_counter << 48; + } if (copy_to_user(argp, &s, sizeof s)) r = -EFAULT; + if (vhost_has_feature(vq, VIRTIO_F_RING_PACKED)) + s.num |= vq->avail_wrap_counter << 31; break; case VHOST_SET_VRING_ADDR: if (copy_from_user(&a, argp, sizeof a)) { Wei Xu (8): virtio: feature bit, data structure, init for packed ring virtio: memory cache for packed ring virtio: empty check and desc read for packed ring virtio: get avail bytes check for packed ring virtio: queue pop support for packed ring virtio: flush/push support for packed ring virtio: event suppression support for packed ring virtio: support guest driver reload for vhost-net hw/net/vhost_net.c | 2 + hw/virtio/virtio.c | 677 +++++++++++++++++++++++-- include/hw/virtio/virtio.h | 4 +- include/standard-headers/linux/virtio_config.h | 15 + 4 files changed, 649 insertions(+), 49 deletions(-) -- 1.8.3.1