From f56a12475ff1b8aa61210d08522c3c8aaf0e2648 Mon Sep 17 00:00:00 2001 From: "Michael S. Tsirkin" Date: Mon, 24 Dec 2012 17:37:01 +0200 Subject: vhost: backend masking support Support backend guest notifier masking in vhost-net: create eventfd at device init, when masked, make vhost use that as eventfd instead of sending an interrupt. Signed-off-by: Michael S. Tsirkin --- hw/vhost.c | 95 +++++++++++++++++++++++++++++++++++++++++++++++++-------- hw/vhost.h | 10 ++++++ hw/vhost_net.c | 27 ++++++++++++++-- hw/vhost_net.h | 3 ++ hw/virtio-net.c | 18 +++++++++++ 5 files changed, 137 insertions(+), 16 deletions(-) (limited to 'hw') diff --git a/hw/vhost.c b/hw/vhost.c index 4fa5007..cee8aad 100644 --- a/hw/vhost.c +++ b/hw/vhost.c @@ -612,7 +612,7 @@ static void vhost_log_stop(MemoryListener *listener, /* FIXME: implement */ } -static int vhost_virtqueue_init(struct vhost_dev *dev, +static int vhost_virtqueue_start(struct vhost_dev *dev, struct VirtIODevice *vdev, struct vhost_virtqueue *vq, unsigned idx) @@ -681,16 +681,11 @@ static int vhost_virtqueue_init(struct vhost_dev *dev, goto fail_kick; } - file.fd = event_notifier_get_fd(virtio_queue_get_guest_notifier(vvq)); - r = ioctl(dev->control, VHOST_SET_VRING_CALL, &file); - if (r) { - r = -errno; - goto fail_call; - } + /* Clear and discard previous events if any. */ + event_notifier_test_and_clear(&vq->masked_notifier); return 0; -fail_call: fail_kick: fail_alloc: cpu_physical_memory_unmap(vq->ring, virtio_queue_get_ring_size(vdev, idx), @@ -708,7 +703,7 @@ fail_alloc_desc: return r; } -static void vhost_virtqueue_cleanup(struct vhost_dev *dev, +static void vhost_virtqueue_stop(struct vhost_dev *dev, struct VirtIODevice *vdev, struct vhost_virtqueue *vq, unsigned idx) @@ -746,11 +741,39 @@ static void vhost_eventfd_del(MemoryListener *listener, { } +static int vhost_virtqueue_init(struct vhost_dev *dev, + struct vhost_virtqueue *vq, int n) +{ + struct vhost_vring_file file = { + .index = n, + }; + int r = event_notifier_init(&vq->masked_notifier, 0); + if (r < 0) { + return r; + } + + file.fd = event_notifier_get_fd(&vq->masked_notifier); + r = ioctl(dev->control, VHOST_SET_VRING_CALL, &file); + if (r) { + r = -errno; + goto fail_call; + } + return 0; +fail_call: + event_notifier_cleanup(&vq->masked_notifier); + return r; +} + +static void vhost_virtqueue_cleanup(struct vhost_virtqueue *vq) +{ + event_notifier_cleanup(&vq->masked_notifier); +} + int vhost_dev_init(struct vhost_dev *hdev, int devfd, const char *devpath, bool force) { uint64_t features; - int r; + int i, r; if (devfd >= 0) { hdev->control = devfd; } else { @@ -768,6 +791,13 @@ int vhost_dev_init(struct vhost_dev *hdev, int devfd, const char *devpath, if (r < 0) { goto fail; } + + for (i = 0; i < hdev->nvqs; ++i) { + r = vhost_virtqueue_init(hdev, hdev->vqs + i, i); + if (r < 0) { + goto fail_vq; + } + } hdev->features = features; hdev->memory_listener = (MemoryListener) { @@ -795,6 +825,10 @@ int vhost_dev_init(struct vhost_dev *hdev, int devfd, const char *devpath, memory_listener_register(&hdev->memory_listener, &address_space_memory); hdev->force = force; return 0; +fail_vq: + while (--i >= 0) { + vhost_virtqueue_cleanup(hdev->vqs + i); + } fail: r = -errno; close(hdev->control); @@ -803,6 +837,10 @@ fail: void vhost_dev_cleanup(struct vhost_dev *hdev) { + int i; + for (i = 0; i < hdev->nvqs; ++i) { + vhost_virtqueue_cleanup(hdev->vqs + i); + } memory_listener_unregister(&hdev->memory_listener); g_free(hdev->mem); g_free(hdev->mem_sections); @@ -869,6 +907,37 @@ void vhost_dev_disable_notifiers(struct vhost_dev *hdev, VirtIODevice *vdev) } } +/* Test and clear event pending status. + * Should be called after unmask to avoid losing events. + */ +bool vhost_virtqueue_pending(struct vhost_dev *hdev, int n) +{ + struct vhost_virtqueue *vq = hdev->vqs + n; + assert(hdev->started); + return event_notifier_test_and_clear(&vq->masked_notifier); +} + +/* Mask/unmask events from this vq. */ +void vhost_virtqueue_mask(struct vhost_dev *hdev, VirtIODevice *vdev, int n, + bool mask) +{ + struct VirtQueue *vvq = virtio_get_queue(vdev, n); + int r; + + assert(hdev->started); + + struct vhost_vring_file file = { + .index = n, + }; + if (mask) { + file.fd = event_notifier_get_fd(&hdev->vqs[n].masked_notifier); + } else { + file.fd = event_notifier_get_fd(virtio_queue_get_guest_notifier(vvq)); + } + r = ioctl(hdev->control, VHOST_SET_VRING_CALL, &file); + assert(r >= 0); +} + /* Host notifiers must be enabled at this point. */ int vhost_dev_start(struct vhost_dev *hdev, VirtIODevice *vdev) { @@ -900,7 +969,7 @@ int vhost_dev_start(struct vhost_dev *hdev, VirtIODevice *vdev) goto fail_mem; } for (i = 0; i < hdev->nvqs; ++i) { - r = vhost_virtqueue_init(hdev, + r = vhost_virtqueue_start(hdev, vdev, hdev->vqs + i, i); @@ -925,7 +994,7 @@ int vhost_dev_start(struct vhost_dev *hdev, VirtIODevice *vdev) fail_log: fail_vq: while (--i >= 0) { - vhost_virtqueue_cleanup(hdev, + vhost_virtqueue_stop(hdev, vdev, hdev->vqs + i, i); @@ -946,7 +1015,7 @@ void vhost_dev_stop(struct vhost_dev *hdev, VirtIODevice *vdev) int i, r; for (i = 0; i < hdev->nvqs; ++i) { - vhost_virtqueue_cleanup(hdev, + vhost_virtqueue_stop(hdev, vdev, hdev->vqs + i, i); diff --git a/hw/vhost.h b/hw/vhost.h index 6f6a906..44c61a5 100644 --- a/hw/vhost.h +++ b/hw/vhost.h @@ -18,6 +18,7 @@ struct vhost_virtqueue { void *ring; unsigned long long ring_phys; unsigned ring_size; + EventNotifier masked_notifier; }; typedef unsigned long vhost_log_chunk_t; @@ -53,4 +54,13 @@ void vhost_dev_stop(struct vhost_dev *hdev, VirtIODevice *vdev); int vhost_dev_enable_notifiers(struct vhost_dev *hdev, VirtIODevice *vdev); void vhost_dev_disable_notifiers(struct vhost_dev *hdev, VirtIODevice *vdev); +/* Test and clear masked event pending status. + * Should be called after unmask to avoid losing events. + */ +bool vhost_virtqueue_pending(struct vhost_dev *hdev, int n); + +/* Mask/unmask events from this vq. + */ +void vhost_virtqueue_mask(struct vhost_dev *hdev, VirtIODevice *vdev, int n, + bool mask); #endif diff --git a/hw/vhost_net.c b/hw/vhost_net.c index ae2785d..d3a04ca 100644 --- a/hw/vhost_net.c +++ b/hw/vhost_net.c @@ -109,6 +109,9 @@ struct vhost_net *vhost_net_init(NetClientState *backend, int devfd, (1 << VHOST_NET_F_VIRTIO_NET_HDR); net->backend = r; + net->dev.nvqs = 2; + net->dev.vqs = net->vqs; + r = vhost_dev_init(&net->dev, devfd, "/dev/vhost-net", force); if (r < 0) { goto fail; @@ -143,9 +146,6 @@ int vhost_net_start(struct vhost_net *net, struct vhost_vring_file file = { }; int r; - net->dev.nvqs = 2; - net->dev.vqs = net->vqs; - r = vhost_dev_enable_notifiers(&net->dev, dev); if (r < 0) { goto fail_notifiers; @@ -200,6 +200,17 @@ void vhost_net_cleanup(struct vhost_net *net) vhost_dev_cleanup(&net->dev); g_free(net); } + +bool vhost_net_virtqueue_pending(VHostNetState *net, int idx) +{ + return vhost_virtqueue_pending(&net->dev, idx); +} + +void vhost_net_virtqueue_mask(VHostNetState *net, VirtIODevice *dev, + int idx, bool mask) +{ + vhost_virtqueue_mask(&net->dev, dev, idx, mask); +} #else struct vhost_net *vhost_net_init(NetClientState *backend, int devfd, bool force) @@ -234,4 +245,14 @@ unsigned vhost_net_get_features(struct vhost_net *net, unsigned features) void vhost_net_ack_features(struct vhost_net *net, unsigned features) { } + +bool vhost_net_virtqueue_pending(VHostNetState *net, int idx) +{ + return -ENOSYS; +} + +void vhost_net_virtqueue_mask(VHostNetState *net, VirtIODevice *dev, + int idx, bool mask) +{ +} #endif diff --git a/hw/vhost_net.h b/hw/vhost_net.h index 012aba4..88912b8 100644 --- a/hw/vhost_net.h +++ b/hw/vhost_net.h @@ -17,4 +17,7 @@ void vhost_net_cleanup(VHostNetState *net); unsigned vhost_net_get_features(VHostNetState *net, unsigned features); void vhost_net_ack_features(VHostNetState *net, unsigned features); +bool vhost_net_virtqueue_pending(VHostNetState *net, int n); +void vhost_net_virtqueue_mask(VHostNetState *net, VirtIODevice *dev, + int idx, bool mask); #endif diff --git a/hw/virtio-net.c b/hw/virtio-net.c index b756d57..3bb01b1 100644 --- a/hw/virtio-net.c +++ b/hw/virtio-net.c @@ -1010,6 +1010,22 @@ static NetClientInfo net_virtio_info = { .link_status_changed = virtio_net_set_link_status, }; +static bool virtio_net_guest_notifier_pending(VirtIODevice *vdev, int idx) +{ + VirtIONet *n = to_virtio_net(vdev); + assert(n->vhost_started); + return vhost_net_virtqueue_pending(tap_get_vhost_net(n->nic->nc.peer), idx); +} + +static void virtio_net_guest_notifier_mask(VirtIODevice *vdev, int idx, + bool mask) +{ + VirtIONet *n = to_virtio_net(vdev); + assert(n->vhost_started); + vhost_net_virtqueue_mask(tap_get_vhost_net(n->nic->nc.peer), + vdev, idx, mask); +} + VirtIODevice *virtio_net_init(DeviceState *dev, NICConf *conf, virtio_net_conf *net) { @@ -1026,6 +1042,8 @@ VirtIODevice *virtio_net_init(DeviceState *dev, NICConf *conf, n->vdev.bad_features = virtio_net_bad_features; n->vdev.reset = virtio_net_reset; n->vdev.set_status = virtio_net_set_status; + n->vdev.guest_notifier_mask = virtio_net_guest_notifier_mask; + n->vdev.guest_notifier_pending = virtio_net_guest_notifier_pending; n->rx_vq = virtio_add_queue(&n->vdev, 256, virtio_net_handle_rx); if (net->tx && strcmp(net->tx, "timer") && strcmp(net->tx, "bh")) { -- cgit v1.1