| Message ID | 20240605145533.86229-3-hengqi@linux.alibaba.com (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | virtio_net: enable the irq for ctrlq | expand |
On Wed, Jun 5, 2024 at 10:56 PM Heng Qi <hengqi@linux.alibaba.com> wrote: > > Currently, the control queue (ctrlq) handles commands synchronously, > leading to increased delays for dim commands during multi-queue > VM configuration and directly impacting dim performance. > > To address this, we are shifting to asynchronous processing of > ctrlq's dim commands. > > Signed-off-by: Heng Qi <hengqi@linux.alibaba.com> > --- > drivers/net/virtio_net.c | 260 +++++++++++++++++++++++++++++++++++---- > 1 file changed, 236 insertions(+), 24 deletions(-) > > diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c > index 9b556ce89546..7975084052ad 100644 > --- a/drivers/net/virtio_net.c > +++ b/drivers/net/virtio_net.c > @@ -270,6 +270,14 @@ struct virtnet_interrupt_coalesce { > u32 max_usecs; > }; > > +struct virtnet_coal_node { > + struct virtio_net_ctrl_hdr hdr; > + virtio_net_ctrl_ack status; > + struct virtio_net_ctrl_coal_vq coal_vqs; > + bool is_coal_wait; > + struct list_head list; > +}; > + > /* The dma information of pages allocated at a time. */ > struct virtnet_rq_dma { > dma_addr_t addr; > @@ -421,6 +429,9 @@ struct virtnet_info { > /* Wait for the device to complete the cvq request. */ > struct completion completion; > > + /* Work struct for acquisition of cvq processing results. */ > + struct work_struct get_cvq; > + > /* Host can handle any s/g split between our header and packet data */ > bool any_header_sg; > > @@ -465,6 +476,14 @@ struct virtnet_info { > struct virtnet_interrupt_coalesce intr_coal_tx; > struct virtnet_interrupt_coalesce intr_coal_rx; > > + /* Free nodes used for concurrent delivery */ > + struct mutex coal_free_lock; > + struct list_head coal_free_list; > + > + /* Filled when there are no free nodes or cvq buffers */ > + struct mutex coal_wait_lock; > + struct list_head coal_wait_list; > + > unsigned long guest_offloads; > unsigned long guest_offloads_capable; > > @@ -671,7 +690,7 @@ static void virtnet_cvq_done(struct virtqueue *cvq) > { > struct virtnet_info *vi = cvq->vdev->priv; > > - complete(&vi->completion); > + schedule_work(&vi->get_cvq); > } > > static void skb_xmit_done(struct virtqueue *vq) > @@ -2183,6 +2202,113 @@ static bool try_fill_recv(struct virtnet_info *vi, struct receive_queue *rq, > return !oom; > } > > +static int __virtnet_add_dim_command(struct virtnet_info *vi, > + struct virtnet_coal_node *ctrl) > +{ > + struct scatterlist *sgs[4], hdr, stat, out; > + unsigned int out_num = 0; > + int ret; > + > + BUG_ON(!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ)); > + > + ctrl->hdr.class = VIRTIO_NET_CTRL_NOTF_COAL; > + ctrl->hdr.cmd = VIRTIO_NET_CTRL_NOTF_COAL_VQ_SET; > + > + sg_init_one(&hdr, &ctrl->hdr, sizeof(ctrl->hdr)); > + sgs[out_num++] = &hdr; > + > + sg_init_one(&out, &ctrl->coal_vqs, sizeof(ctrl->coal_vqs)); > + sgs[out_num++] = &out; > + > + ctrl->status = ~0; > + sg_init_one(&stat, &ctrl->status, sizeof(ctrl->status)); > + sgs[out_num] = &stat; > + > + BUG_ON(out_num + 1 > ARRAY_SIZE(sgs)); > + ret = virtqueue_add_sgs(vi->cvq, sgs, out_num, 1, ctrl, GFP_ATOMIC); > + if (ret < 0) { > + dev_warn(&vi->vdev->dev, > + "Failed to add sgs for command vq: %d\n.", ret); > + return ret; > + } > + > + if (unlikely(!virtqueue_kick(vi->cvq))) > + return -EIO; > + > + return 0; > +} > + > +static int virtnet_add_dim_command(struct virtnet_info *vi, > + struct virtnet_coal_node *ctrl) > +{ > + int ret; > + > + mutex_lock(&vi->cvq_lock); > + ret = __virtnet_add_dim_command(vi, ctrl); > + mutex_unlock(&vi->cvq_lock); > + > + return ret; > +} > + > +static void virtnet_process_dim_cmd(struct virtnet_info *vi, void *res) > +{ > + struct virtnet_coal_node *node = (struct virtnet_coal_node *)res; > + u16 qnum = le16_to_cpu(node->coal_vqs.vqn) / 2; > + > + mutex_lock(&vi->rq[qnum].dim_lock); > + vi->rq[qnum].intr_coal.max_usecs = > + le32_to_cpu(node->coal_vqs.coal.max_usecs); > + vi->rq[qnum].intr_coal.max_packets = > + le32_to_cpu(node->coal_vqs.coal.max_packets); > + vi->rq[qnum].dim.state = DIM_START_MEASURE; > + mutex_unlock(&vi->rq[qnum].dim_lock); > + > + if (node->is_coal_wait) { > + kfree(node); > + } else { > + mutex_lock(&vi->coal_free_lock); > + list_add(&node->list, &vi->coal_free_list); > + mutex_unlock(&vi->coal_free_lock); > + } > +} > + > +static void virtnet_get_cvq_work(struct work_struct *work) > +{ > + struct virtnet_info *vi = > + container_of(work, struct virtnet_info, get_cvq); > + struct virtnet_coal_node *wait_coal; > + bool valid = false; > + unsigned int tmp; > + void *res; > + > + mutex_lock(&vi->cvq_lock); > + while ((res = virtqueue_get_buf(vi->cvq, &tmp)) != NULL) { > + if (res == ((void *)vi)) > + complete(&vi->completion); > + else > + virtnet_process_dim_cmd(vi, res); This seems an ad-hoc optimization for dim? Instead of doing this, I wonder if we can make it re-usable for other possible use cases. For example, just allocation completion and store the completion as a token. Then virtqueue_get_buf can wake up the correct completion? Thanks > + > + valid = true; > + } > + > + if (!valid) { > + mutex_unlock(&vi->cvq_lock); > + return; > + } > + > + mutex_lock(&vi->coal_wait_lock); > + while (!list_empty(&vi->coal_wait_list)) { > + wait_coal = list_first_entry(&vi->coal_wait_list, > + struct virtnet_coal_node, list); > + if (__virtnet_add_dim_command(vi, wait_coal)) > + break; > + list_del(&wait_coal->list); > + } > + mutex_unlock(&vi->coal_wait_lock); > + > + mutex_unlock(&vi->cvq_lock); > +} > + > static void skb_recv_done(struct virtqueue *rvq) > { > struct virtnet_info *vi = rvq->vdev->priv; > @@ -2695,7 +2821,7 @@ static bool virtnet_send_command_reply(struct virtnet_info *vi, u8 class, u8 cmd > struct scatterlist *in) > { > struct scatterlist *sgs[5], hdr, stat; > - u32 out_num = 0, tmp, in_num = 0; > + u32 out_num = 0, in_num = 0; > int ret; > > /* Caller should know better */ > @@ -2728,14 +2854,15 @@ static bool virtnet_send_command_reply(struct virtnet_info *vi, u8 class, u8 cmd > return false; > } > > - if (unlikely(!virtqueue_kick(vi->cvq))) > - goto unlock; > + if (unlikely(!virtqueue_kick(vi->cvq))) { > + mutex_unlock(&vi->cvq_lock); > + return false; > + } > + > + mutex_unlock(&vi->cvq_lock); > > wait_for_completion(&vi->completion); > - virtqueue_get_buf(vi->cvq, &tmp); > > -unlock: > - mutex_unlock(&vi->cvq_lock); > return vi->ctrl->status == VIRTIO_NET_OK; > } > > @@ -4396,35 +4523,73 @@ static int virtnet_send_notf_coal_vq_cmds(struct virtnet_info *vi, > return 0; > } > > +static void virtnet_put_wait_coal(struct virtnet_info *vi, > + struct receive_queue *rq, > + struct dim_cq_moder moder) > +{ > + struct virtnet_coal_node *wait_node; > + > + wait_node = kzalloc(sizeof(*wait_node), GFP_KERNEL); > + if (!wait_node) { > + rq->dim.state = DIM_START_MEASURE; > + return; > + } > + > + wait_node->is_coal_wait = true; > + wait_node->coal_vqs.vqn = cpu_to_le16(rxq2vq(rq - vi->rq)); > + wait_node->coal_vqs.coal.max_usecs = cpu_to_le32(moder.usec); > + wait_node->coal_vqs.coal.max_packets = cpu_to_le32(moder.pkts); > + mutex_lock(&vi->coal_wait_lock); > + list_add_tail(&wait_node->list, &vi->coal_wait_list); > + mutex_unlock(&vi->coal_wait_lock); > +} > + > static void virtnet_rx_dim_work(struct work_struct *work) > { > struct dim *dim = container_of(work, struct dim, work); > struct receive_queue *rq = container_of(dim, > struct receive_queue, dim); > struct virtnet_info *vi = rq->vq->vdev->priv; > - struct net_device *dev = vi->dev; > + struct virtnet_coal_node *avail_coal; > struct dim_cq_moder update_moder; > - int qnum, err; > > - qnum = rq - vi->rq; > + update_moder = net_dim_get_rx_moderation(dim->mode, dim->profile_ix); > > mutex_lock(&rq->dim_lock); > - if (!rq->dim_enabled) > - goto out; > - > - update_moder = net_dim_get_rx_moderation(dim->mode, dim->profile_ix); > - if (update_moder.usec != rq->intr_coal.max_usecs || > - update_moder.pkts != rq->intr_coal.max_packets) { > - err = virtnet_send_rx_ctrl_coal_vq_cmd(vi, qnum, > - update_moder.usec, > - update_moder.pkts); > - if (err) > - pr_debug("%s: Failed to send dim parameters on rxq%d\n", > - dev->name, qnum); > - dim->state = DIM_START_MEASURE; > + if (!rq->dim_enabled || > + (update_moder.usec == rq->intr_coal.max_usecs && > + update_moder.pkts == rq->intr_coal.max_packets)) { > + rq->dim.state = DIM_START_MEASURE; > + mutex_unlock(&rq->dim_lock); > + return; > } > -out: > mutex_unlock(&rq->dim_lock); > + > + mutex_lock(&vi->cvq_lock); > + if (vi->cvq->num_free < 3) { > + virtnet_put_wait_coal(vi, rq, update_moder); > + mutex_unlock(&vi->cvq_lock); > + return; > + } > + mutex_unlock(&vi->cvq_lock); > + > + mutex_lock(&vi->coal_free_lock); > + if (list_empty(&vi->coal_free_list)) { > + virtnet_put_wait_coal(vi, rq, update_moder); > + mutex_unlock(&vi->coal_free_lock); > + return; > + } > + > + avail_coal = list_first_entry(&vi->coal_free_list, > + struct virtnet_coal_node, list); > + avail_coal->coal_vqs.vqn = cpu_to_le16(rxq2vq(rq - vi->rq)); > + avail_coal->coal_vqs.coal.max_usecs = cpu_to_le32(update_moder.usec); > + avail_coal->coal_vqs.coal.max_packets = cpu_to_le32(update_moder.pkts); > + > + list_del(&avail_coal->list); > + mutex_unlock(&vi->coal_free_lock); > + > + virtnet_add_dim_command(vi, avail_coal); > } > > static int virtnet_coal_params_supported(struct ethtool_coalesce *ec) > @@ -4837,6 +5002,7 @@ static void virtnet_freeze_down(struct virtio_device *vdev) > flush_work(&vi->config_work); > disable_rx_mode_work(vi); > flush_work(&vi->rx_mode_work); > + flush_work(&vi->get_cvq); > > netif_tx_lock_bh(vi->dev); > netif_device_detach(vi->dev); > @@ -5610,6 +5776,45 @@ static const struct xdp_metadata_ops virtnet_xdp_metadata_ops = { > .xmo_rx_hash = virtnet_xdp_rx_hash, > }; > > +static void virtnet_del_coal_free_list(struct virtnet_info *vi) > +{ > + struct virtnet_coal_node *coal_node, *tmp; > + > + list_for_each_entry_safe(coal_node, tmp, &vi->coal_free_list, list) { > + list_del(&coal_node->list); > + kfree(coal_node); > + } > +} > + > +static int virtnet_init_coal_list(struct virtnet_info *vi) > +{ > + struct virtnet_coal_node *coal_node; > + int batch_dim_nums; > + int i; > + > + INIT_LIST_HEAD(&vi->coal_free_list); > + mutex_init(&vi->coal_free_lock); > + > + INIT_LIST_HEAD(&vi->coal_wait_list); > + mutex_init(&vi->coal_wait_lock); > + > + if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_VQ_NOTF_COAL)) > + return 0; > + > + batch_dim_nums = min((unsigned int)vi->max_queue_pairs, > + virtqueue_get_vring_size(vi->cvq) / 3); > + for (i = 0; i < batch_dim_nums; i++) { > + coal_node = kzalloc(sizeof(*coal_node), GFP_KERNEL); > + if (!coal_node) { > + virtnet_del_coal_free_list(vi); > + return -ENOMEM; > + } > + list_add(&coal_node->list, &vi->coal_free_list); > + } > + > + return 0; > +} > + > static int virtnet_probe(struct virtio_device *vdev) > { > int i, err = -ENOMEM; > @@ -5795,6 +6000,9 @@ static int virtnet_probe(struct virtio_device *vdev) > if (err) > goto free; > > + if (virtnet_init_coal_list(vi)) > + goto free; > + > if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_NOTF_COAL)) { > vi->intr_coal_rx.max_usecs = 0; > vi->intr_coal_tx.max_usecs = 0; > @@ -5836,6 +6044,7 @@ static int virtnet_probe(struct virtio_device *vdev) > if (vi->has_rss || vi->has_rss_hash_report) > virtnet_init_default_rss(vi); > > + INIT_WORK(&vi->get_cvq, virtnet_get_cvq_work); > init_completion(&vi->completion); > enable_rx_mode_work(vi); > > @@ -5965,11 +6174,14 @@ static void virtnet_remove(struct virtio_device *vdev) > flush_work(&vi->config_work); > disable_rx_mode_work(vi); > flush_work(&vi->rx_mode_work); > + flush_work(&vi->get_cvq); > > unregister_netdev(vi->dev); > > net_failover_destroy(vi->failover); > > + virtnet_del_coal_free_list(vi); > + > remove_vq_common(vi); > > free_netdev(vi->dev); > -- > 2.32.0.3.g01195cf9f >
On Thu, 6 Jun 2024 08:27:35 +0800, Jason Wang <jasowang@redhat.com> wrote: > On Wed, Jun 5, 2024 at 10:56 PM Heng Qi <hengqi@linux.alibaba.com> wrote: > > > > Currently, the control queue (ctrlq) handles commands synchronously, > > leading to increased delays for dim commands during multi-queue > > VM configuration and directly impacting dim performance. > > > > To address this, we are shifting to asynchronous processing of > > ctrlq's dim commands. > > > > Signed-off-by: Heng Qi <hengqi@linux.alibaba.com> > > --- > > drivers/net/virtio_net.c | 260 +++++++++++++++++++++++++++++++++++---- > > 1 file changed, 236 insertions(+), 24 deletions(-) > > > > diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c > > index 9b556ce89546..7975084052ad 100644 > > --- a/drivers/net/virtio_net.c > > +++ b/drivers/net/virtio_net.c > > @@ -270,6 +270,14 @@ struct virtnet_interrupt_coalesce { > > u32 max_usecs; > > }; > > > > +struct virtnet_coal_node { > > + struct virtio_net_ctrl_hdr hdr; > > + virtio_net_ctrl_ack status; > > + struct virtio_net_ctrl_coal_vq coal_vqs; > > + bool is_coal_wait; > > + struct list_head list; > > +}; > > + > > /* The dma information of pages allocated at a time. */ > > struct virtnet_rq_dma { > > dma_addr_t addr; > > @@ -421,6 +429,9 @@ struct virtnet_info { > > /* Wait for the device to complete the cvq request. */ > > struct completion completion; > > > > + /* Work struct for acquisition of cvq processing results. */ > > + struct work_struct get_cvq; > > + > > /* Host can handle any s/g split between our header and packet data */ > > bool any_header_sg; > > > > @@ -465,6 +476,14 @@ struct virtnet_info { > > struct virtnet_interrupt_coalesce intr_coal_tx; > > struct virtnet_interrupt_coalesce intr_coal_rx; > > > > + /* Free nodes used for concurrent delivery */ > > + struct mutex coal_free_lock; > > + struct list_head coal_free_list; > > + > > + /* Filled when there are no free nodes or cvq buffers */ > > + struct mutex coal_wait_lock; > > + struct list_head coal_wait_list; > > + > > unsigned long guest_offloads; > > unsigned long guest_offloads_capable; > > > > @@ -671,7 +690,7 @@ static void virtnet_cvq_done(struct virtqueue *cvq) > > { > > struct virtnet_info *vi = cvq->vdev->priv; > > > > - complete(&vi->completion); > > + schedule_work(&vi->get_cvq); > > } > > > > static void skb_xmit_done(struct virtqueue *vq) > > @@ -2183,6 +2202,113 @@ static bool try_fill_recv(struct virtnet_info *vi, struct receive_queue *rq, > > return !oom; > > } > > > > +static int __virtnet_add_dim_command(struct virtnet_info *vi, > > + struct virtnet_coal_node *ctrl) > > +{ > > + struct scatterlist *sgs[4], hdr, stat, out; > > + unsigned int out_num = 0; > > + int ret; > > + > > + BUG_ON(!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ)); > > + > > + ctrl->hdr.class = VIRTIO_NET_CTRL_NOTF_COAL; > > + ctrl->hdr.cmd = VIRTIO_NET_CTRL_NOTF_COAL_VQ_SET; > > + > > + sg_init_one(&hdr, &ctrl->hdr, sizeof(ctrl->hdr)); > > + sgs[out_num++] = &hdr; > > + > > + sg_init_one(&out, &ctrl->coal_vqs, sizeof(ctrl->coal_vqs)); > > + sgs[out_num++] = &out; > > + > > + ctrl->status = ~0; > > + sg_init_one(&stat, &ctrl->status, sizeof(ctrl->status)); > > + sgs[out_num] = &stat; > > + > > + BUG_ON(out_num + 1 > ARRAY_SIZE(sgs)); > > + ret = virtqueue_add_sgs(vi->cvq, sgs, out_num, 1, ctrl, GFP_ATOMIC); > > + if (ret < 0) { > > + dev_warn(&vi->vdev->dev, > > + "Failed to add sgs for command vq: %d\n.", ret); > > + return ret; > > + } > > + > > + if (unlikely(!virtqueue_kick(vi->cvq))) > > + return -EIO; > > + > > + return 0; > > +} > > + > > +static int virtnet_add_dim_command(struct virtnet_info *vi, > > + struct virtnet_coal_node *ctrl) > > +{ > > + int ret; > > + > > + mutex_lock(&vi->cvq_lock); > > + ret = __virtnet_add_dim_command(vi, ctrl); > > + mutex_unlock(&vi->cvq_lock); > > + > > + return ret; > > +} > > + > > +static void virtnet_process_dim_cmd(struct virtnet_info *vi, void *res) > > +{ > > + struct virtnet_coal_node *node = (struct virtnet_coal_node *)res; > > + u16 qnum = le16_to_cpu(node->coal_vqs.vqn) / 2; > > + > > + mutex_lock(&vi->rq[qnum].dim_lock); > > + vi->rq[qnum].intr_coal.max_usecs = > > + le32_to_cpu(node->coal_vqs.coal.max_usecs); > > + vi->rq[qnum].intr_coal.max_packets = > > + le32_to_cpu(node->coal_vqs.coal.max_packets); > > + vi->rq[qnum].dim.state = DIM_START_MEASURE; > > + mutex_unlock(&vi->rq[qnum].dim_lock); > > + > > + if (node->is_coal_wait) { > > + kfree(node); > > + } else { > > + mutex_lock(&vi->coal_free_lock); > > + list_add(&node->list, &vi->coal_free_list); > > + mutex_unlock(&vi->coal_free_lock); > > + } > > +} > > + > > +static void virtnet_get_cvq_work(struct work_struct *work) > > +{ > > + struct virtnet_info *vi = > > + container_of(work, struct virtnet_info, get_cvq); > > + struct virtnet_coal_node *wait_coal; > > + bool valid = false; > > + unsigned int tmp; > > + void *res; > > + > > + mutex_lock(&vi->cvq_lock); > > + while ((res = virtqueue_get_buf(vi->cvq, &tmp)) != NULL) { > > + if (res == ((void *)vi)) > > + complete(&vi->completion); > > + else > > + virtnet_process_dim_cmd(vi, res); > > This seems an ad-hoc optimization for dim? Instead of doing this, I > wonder if we can make it re-usable for other possible use cases. > The purpose of this is that I don't see the need for concurrent ctrlq requests in addition to dim. But I can try your suggestion. Thanks. > For example, just allocation completion and store the completion as a > token. Then virtqueue_get_buf can wake up the correct completion? > > Thanks > > > + > > + valid = true; > > + } > > + > > + if (!valid) { > > + mutex_unlock(&vi->cvq_lock); > > + return; > > + } > > + > > + mutex_lock(&vi->coal_wait_lock); > > + while (!list_empty(&vi->coal_wait_list)) { > > + wait_coal = list_first_entry(&vi->coal_wait_list, > > + struct virtnet_coal_node, list); > > + if (__virtnet_add_dim_command(vi, wait_coal)) > > + break; > > + list_del(&wait_coal->list); > > + } > > + mutex_unlock(&vi->coal_wait_lock); > > + > > + mutex_unlock(&vi->cvq_lock); > > +} > > + > > static void skb_recv_done(struct virtqueue *rvq) > > { > > struct virtnet_info *vi = rvq->vdev->priv; > > @@ -2695,7 +2821,7 @@ static bool virtnet_send_command_reply(struct virtnet_info *vi, u8 class, u8 cmd > > struct scatterlist *in) > > { > > struct scatterlist *sgs[5], hdr, stat; > > - u32 out_num = 0, tmp, in_num = 0; > > + u32 out_num = 0, in_num = 0; > > int ret; > > > > /* Caller should know better */ > > @@ -2728,14 +2854,15 @@ static bool virtnet_send_command_reply(struct virtnet_info *vi, u8 class, u8 cmd > > return false; > > } > > > > - if (unlikely(!virtqueue_kick(vi->cvq))) > > - goto unlock; > > + if (unlikely(!virtqueue_kick(vi->cvq))) { > > + mutex_unlock(&vi->cvq_lock); > > + return false; > > + } > > + > > + mutex_unlock(&vi->cvq_lock); > > > > wait_for_completion(&vi->completion); > > - virtqueue_get_buf(vi->cvq, &tmp); > > > > -unlock: > > - mutex_unlock(&vi->cvq_lock); > > return vi->ctrl->status == VIRTIO_NET_OK; > > } > > > > @@ -4396,35 +4523,73 @@ static int virtnet_send_notf_coal_vq_cmds(struct virtnet_info *vi, > > return 0; > > } > > > > +static void virtnet_put_wait_coal(struct virtnet_info *vi, > > + struct receive_queue *rq, > > + struct dim_cq_moder moder) > > +{ > > + struct virtnet_coal_node *wait_node; > > + > > + wait_node = kzalloc(sizeof(*wait_node), GFP_KERNEL); > > + if (!wait_node) { > > + rq->dim.state = DIM_START_MEASURE; > > + return; > > + } > > + > > + wait_node->is_coal_wait = true; > > + wait_node->coal_vqs.vqn = cpu_to_le16(rxq2vq(rq - vi->rq)); > > + wait_node->coal_vqs.coal.max_usecs = cpu_to_le32(moder.usec); > > + wait_node->coal_vqs.coal.max_packets = cpu_to_le32(moder.pkts); > > + mutex_lock(&vi->coal_wait_lock); > > + list_add_tail(&wait_node->list, &vi->coal_wait_list); > > + mutex_unlock(&vi->coal_wait_lock); > > +} > > + > > static void virtnet_rx_dim_work(struct work_struct *work) > > { > > struct dim *dim = container_of(work, struct dim, work); > > struct receive_queue *rq = container_of(dim, > > struct receive_queue, dim); > > struct virtnet_info *vi = rq->vq->vdev->priv; > > - struct net_device *dev = vi->dev; > > + struct virtnet_coal_node *avail_coal; > > struct dim_cq_moder update_moder; > > - int qnum, err; > > > > - qnum = rq - vi->rq; > > + update_moder = net_dim_get_rx_moderation(dim->mode, dim->profile_ix); > > > > mutex_lock(&rq->dim_lock); > > - if (!rq->dim_enabled) > > - goto out; > > - > > - update_moder = net_dim_get_rx_moderation(dim->mode, dim->profile_ix); > > - if (update_moder.usec != rq->intr_coal.max_usecs || > > - update_moder.pkts != rq->intr_coal.max_packets) { > > - err = virtnet_send_rx_ctrl_coal_vq_cmd(vi, qnum, > > - update_moder.usec, > > - update_moder.pkts); > > - if (err) > > - pr_debug("%s: Failed to send dim parameters on rxq%d\n", > > - dev->name, qnum); > > - dim->state = DIM_START_MEASURE; > > + if (!rq->dim_enabled || > > + (update_moder.usec == rq->intr_coal.max_usecs && > > + update_moder.pkts == rq->intr_coal.max_packets)) { > > + rq->dim.state = DIM_START_MEASURE; > > + mutex_unlock(&rq->dim_lock); > > + return; > > } > > -out: > > mutex_unlock(&rq->dim_lock); > > + > > + mutex_lock(&vi->cvq_lock); > > + if (vi->cvq->num_free < 3) { > > + virtnet_put_wait_coal(vi, rq, update_moder); > > + mutex_unlock(&vi->cvq_lock); > > + return; > > + } > > + mutex_unlock(&vi->cvq_lock); > > + > > + mutex_lock(&vi->coal_free_lock); > > + if (list_empty(&vi->coal_free_list)) { > > + virtnet_put_wait_coal(vi, rq, update_moder); > > + mutex_unlock(&vi->coal_free_lock); > > + return; > > + } > > + > > + avail_coal = list_first_entry(&vi->coal_free_list, > > + struct virtnet_coal_node, list); > > + avail_coal->coal_vqs.vqn = cpu_to_le16(rxq2vq(rq - vi->rq)); > > + avail_coal->coal_vqs.coal.max_usecs = cpu_to_le32(update_moder.usec); > > + avail_coal->coal_vqs.coal.max_packets = cpu_to_le32(update_moder.pkts); > > + > > + list_del(&avail_coal->list); > > + mutex_unlock(&vi->coal_free_lock); > > + > > + virtnet_add_dim_command(vi, avail_coal); > > } > > > > static int virtnet_coal_params_supported(struct ethtool_coalesce *ec) > > @@ -4837,6 +5002,7 @@ static void virtnet_freeze_down(struct virtio_device *vdev) > > flush_work(&vi->config_work); > > disable_rx_mode_work(vi); > > flush_work(&vi->rx_mode_work); > > + flush_work(&vi->get_cvq); > > > > netif_tx_lock_bh(vi->dev); > > netif_device_detach(vi->dev); > > @@ -5610,6 +5776,45 @@ static const struct xdp_metadata_ops virtnet_xdp_metadata_ops = { > > .xmo_rx_hash = virtnet_xdp_rx_hash, > > }; > > > > +static void virtnet_del_coal_free_list(struct virtnet_info *vi) > > +{ > > + struct virtnet_coal_node *coal_node, *tmp; > > + > > + list_for_each_entry_safe(coal_node, tmp, &vi->coal_free_list, list) { > > + list_del(&coal_node->list); > > + kfree(coal_node); > > + } > > +} > > + > > +static int virtnet_init_coal_list(struct virtnet_info *vi) > > +{ > > + struct virtnet_coal_node *coal_node; > > + int batch_dim_nums; > > + int i; > > + > > + INIT_LIST_HEAD(&vi->coal_free_list); > > + mutex_init(&vi->coal_free_lock); > > + > > + INIT_LIST_HEAD(&vi->coal_wait_list); > > + mutex_init(&vi->coal_wait_lock); > > + > > + if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_VQ_NOTF_COAL)) > > + return 0; > > + > > + batch_dim_nums = min((unsigned int)vi->max_queue_pairs, > > + virtqueue_get_vring_size(vi->cvq) / 3); > > + for (i = 0; i < batch_dim_nums; i++) { > > + coal_node = kzalloc(sizeof(*coal_node), GFP_KERNEL); > > + if (!coal_node) { > > + virtnet_del_coal_free_list(vi); > > + return -ENOMEM; > > + } > > + list_add(&coal_node->list, &vi->coal_free_list); > > + } > > + > > + return 0; > > +} > > + > > static int virtnet_probe(struct virtio_device *vdev) > > { > > int i, err = -ENOMEM; > > @@ -5795,6 +6000,9 @@ static int virtnet_probe(struct virtio_device *vdev) > > if (err) > > goto free; > > > > + if (virtnet_init_coal_list(vi)) > > + goto free; > > + > > if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_NOTF_COAL)) { > > vi->intr_coal_rx.max_usecs = 0; > > vi->intr_coal_tx.max_usecs = 0; > > @@ -5836,6 +6044,7 @@ static int virtnet_probe(struct virtio_device *vdev) > > if (vi->has_rss || vi->has_rss_hash_report) > > virtnet_init_default_rss(vi); > > > > + INIT_WORK(&vi->get_cvq, virtnet_get_cvq_work); > > init_completion(&vi->completion); > > enable_rx_mode_work(vi); > > > > @@ -5965,11 +6174,14 @@ static void virtnet_remove(struct virtio_device *vdev) > > flush_work(&vi->config_work); > > disable_rx_mode_work(vi); > > flush_work(&vi->rx_mode_work); > > + flush_work(&vi->get_cvq); > > > > unregister_netdev(vi->dev); > > > > net_failover_destroy(vi->failover); > > > > + virtnet_del_coal_free_list(vi); > > + > > remove_vq_common(vi); > > > > free_netdev(vi->dev); > > -- > > 2.32.0.3.g01195cf9f > > >
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index 9b556ce89546..7975084052ad 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -270,6 +270,14 @@ struct virtnet_interrupt_coalesce { u32 max_usecs; }; +struct virtnet_coal_node { + struct virtio_net_ctrl_hdr hdr; + virtio_net_ctrl_ack status; + struct virtio_net_ctrl_coal_vq coal_vqs; + bool is_coal_wait; + struct list_head list; +}; + /* The dma information of pages allocated at a time. */ struct virtnet_rq_dma { dma_addr_t addr; @@ -421,6 +429,9 @@ struct virtnet_info { /* Wait for the device to complete the cvq request. */ struct completion completion; + /* Work struct for acquisition of cvq processing results. */ + struct work_struct get_cvq; + /* Host can handle any s/g split between our header and packet data */ bool any_header_sg; @@ -465,6 +476,14 @@ struct virtnet_info { struct virtnet_interrupt_coalesce intr_coal_tx; struct virtnet_interrupt_coalesce intr_coal_rx; + /* Free nodes used for concurrent delivery */ + struct mutex coal_free_lock; + struct list_head coal_free_list; + + /* Filled when there are no free nodes or cvq buffers */ + struct mutex coal_wait_lock; + struct list_head coal_wait_list; + unsigned long guest_offloads; unsigned long guest_offloads_capable; @@ -671,7 +690,7 @@ static void virtnet_cvq_done(struct virtqueue *cvq) { struct virtnet_info *vi = cvq->vdev->priv; - complete(&vi->completion); + schedule_work(&vi->get_cvq); } static void skb_xmit_done(struct virtqueue *vq) @@ -2183,6 +2202,113 @@ static bool try_fill_recv(struct virtnet_info *vi, struct receive_queue *rq, return !oom; } +static int __virtnet_add_dim_command(struct virtnet_info *vi, + struct virtnet_coal_node *ctrl) +{ + struct scatterlist *sgs[4], hdr, stat, out; + unsigned int out_num = 0; + int ret; + + BUG_ON(!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ)); + + ctrl->hdr.class = VIRTIO_NET_CTRL_NOTF_COAL; + ctrl->hdr.cmd = VIRTIO_NET_CTRL_NOTF_COAL_VQ_SET; + + sg_init_one(&hdr, &ctrl->hdr, sizeof(ctrl->hdr)); + sgs[out_num++] = &hdr; + + sg_init_one(&out, &ctrl->coal_vqs, sizeof(ctrl->coal_vqs)); + sgs[out_num++] = &out; + + ctrl->status = ~0; + sg_init_one(&stat, &ctrl->status, sizeof(ctrl->status)); + sgs[out_num] = &stat; + + BUG_ON(out_num + 1 > ARRAY_SIZE(sgs)); + ret = virtqueue_add_sgs(vi->cvq, sgs, out_num, 1, ctrl, GFP_ATOMIC); + if (ret < 0) { + dev_warn(&vi->vdev->dev, + "Failed to add sgs for command vq: %d\n.", ret); + return ret; + } + + if (unlikely(!virtqueue_kick(vi->cvq))) + return -EIO; + + return 0; +} + +static int virtnet_add_dim_command(struct virtnet_info *vi, + struct virtnet_coal_node *ctrl) +{ + int ret; + + mutex_lock(&vi->cvq_lock); + ret = __virtnet_add_dim_command(vi, ctrl); + mutex_unlock(&vi->cvq_lock); + + return ret; +} + +static void virtnet_process_dim_cmd(struct virtnet_info *vi, void *res) +{ + struct virtnet_coal_node *node = (struct virtnet_coal_node *)res; + u16 qnum = le16_to_cpu(node->coal_vqs.vqn) / 2; + + mutex_lock(&vi->rq[qnum].dim_lock); + vi->rq[qnum].intr_coal.max_usecs = + le32_to_cpu(node->coal_vqs.coal.max_usecs); + vi->rq[qnum].intr_coal.max_packets = + le32_to_cpu(node->coal_vqs.coal.max_packets); + vi->rq[qnum].dim.state = DIM_START_MEASURE; + mutex_unlock(&vi->rq[qnum].dim_lock); + + if (node->is_coal_wait) { + kfree(node); + } else { + mutex_lock(&vi->coal_free_lock); + list_add(&node->list, &vi->coal_free_list); + mutex_unlock(&vi->coal_free_lock); + } +} + +static void virtnet_get_cvq_work(struct work_struct *work) +{ + struct virtnet_info *vi = + container_of(work, struct virtnet_info, get_cvq); + struct virtnet_coal_node *wait_coal; + bool valid = false; + unsigned int tmp; + void *res; + + mutex_lock(&vi->cvq_lock); + while ((res = virtqueue_get_buf(vi->cvq, &tmp)) != NULL) { + if (res == ((void *)vi)) + complete(&vi->completion); + else + virtnet_process_dim_cmd(vi, res); + + valid = true; + } + + if (!valid) { + mutex_unlock(&vi->cvq_lock); + return; + } + + mutex_lock(&vi->coal_wait_lock); + while (!list_empty(&vi->coal_wait_list)) { + wait_coal = list_first_entry(&vi->coal_wait_list, + struct virtnet_coal_node, list); + if (__virtnet_add_dim_command(vi, wait_coal)) + break; + list_del(&wait_coal->list); + } + mutex_unlock(&vi->coal_wait_lock); + + mutex_unlock(&vi->cvq_lock); +} + static void skb_recv_done(struct virtqueue *rvq) { struct virtnet_info *vi = rvq->vdev->priv; @@ -2695,7 +2821,7 @@ static bool virtnet_send_command_reply(struct virtnet_info *vi, u8 class, u8 cmd struct scatterlist *in) { struct scatterlist *sgs[5], hdr, stat; - u32 out_num = 0, tmp, in_num = 0; + u32 out_num = 0, in_num = 0; int ret; /* Caller should know better */ @@ -2728,14 +2854,15 @@ static bool virtnet_send_command_reply(struct virtnet_info *vi, u8 class, u8 cmd return false; } - if (unlikely(!virtqueue_kick(vi->cvq))) - goto unlock; + if (unlikely(!virtqueue_kick(vi->cvq))) { + mutex_unlock(&vi->cvq_lock); + return false; + } + + mutex_unlock(&vi->cvq_lock); wait_for_completion(&vi->completion); - virtqueue_get_buf(vi->cvq, &tmp); -unlock: - mutex_unlock(&vi->cvq_lock); return vi->ctrl->status == VIRTIO_NET_OK; } @@ -4396,35 +4523,73 @@ static int virtnet_send_notf_coal_vq_cmds(struct virtnet_info *vi, return 0; } +static void virtnet_put_wait_coal(struct virtnet_info *vi, + struct receive_queue *rq, + struct dim_cq_moder moder) +{ + struct virtnet_coal_node *wait_node; + + wait_node = kzalloc(sizeof(*wait_node), GFP_KERNEL); + if (!wait_node) { + rq->dim.state = DIM_START_MEASURE; + return; + } + + wait_node->is_coal_wait = true; + wait_node->coal_vqs.vqn = cpu_to_le16(rxq2vq(rq - vi->rq)); + wait_node->coal_vqs.coal.max_usecs = cpu_to_le32(moder.usec); + wait_node->coal_vqs.coal.max_packets = cpu_to_le32(moder.pkts); + mutex_lock(&vi->coal_wait_lock); + list_add_tail(&wait_node->list, &vi->coal_wait_list); + mutex_unlock(&vi->coal_wait_lock); +} + static void virtnet_rx_dim_work(struct work_struct *work) { struct dim *dim = container_of(work, struct dim, work); struct receive_queue *rq = container_of(dim, struct receive_queue, dim); struct virtnet_info *vi = rq->vq->vdev->priv; - struct net_device *dev = vi->dev; + struct virtnet_coal_node *avail_coal; struct dim_cq_moder update_moder; - int qnum, err; - qnum = rq - vi->rq; + update_moder = net_dim_get_rx_moderation(dim->mode, dim->profile_ix); mutex_lock(&rq->dim_lock); - if (!rq->dim_enabled) - goto out; - - update_moder = net_dim_get_rx_moderation(dim->mode, dim->profile_ix); - if (update_moder.usec != rq->intr_coal.max_usecs || - update_moder.pkts != rq->intr_coal.max_packets) { - err = virtnet_send_rx_ctrl_coal_vq_cmd(vi, qnum, - update_moder.usec, - update_moder.pkts); - if (err) - pr_debug("%s: Failed to send dim parameters on rxq%d\n", - dev->name, qnum); - dim->state = DIM_START_MEASURE; + if (!rq->dim_enabled || + (update_moder.usec == rq->intr_coal.max_usecs && + update_moder.pkts == rq->intr_coal.max_packets)) { + rq->dim.state = DIM_START_MEASURE; + mutex_unlock(&rq->dim_lock); + return; } -out: mutex_unlock(&rq->dim_lock); + + mutex_lock(&vi->cvq_lock); + if (vi->cvq->num_free < 3) { + virtnet_put_wait_coal(vi, rq, update_moder); + mutex_unlock(&vi->cvq_lock); + return; + } + mutex_unlock(&vi->cvq_lock); + + mutex_lock(&vi->coal_free_lock); + if (list_empty(&vi->coal_free_list)) { + virtnet_put_wait_coal(vi, rq, update_moder); + mutex_unlock(&vi->coal_free_lock); + return; + } + + avail_coal = list_first_entry(&vi->coal_free_list, + struct virtnet_coal_node, list); + avail_coal->coal_vqs.vqn = cpu_to_le16(rxq2vq(rq - vi->rq)); + avail_coal->coal_vqs.coal.max_usecs = cpu_to_le32(update_moder.usec); + avail_coal->coal_vqs.coal.max_packets = cpu_to_le32(update_moder.pkts); + + list_del(&avail_coal->list); + mutex_unlock(&vi->coal_free_lock); + + virtnet_add_dim_command(vi, avail_coal); } static int virtnet_coal_params_supported(struct ethtool_coalesce *ec) @@ -4837,6 +5002,7 @@ static void virtnet_freeze_down(struct virtio_device *vdev) flush_work(&vi->config_work); disable_rx_mode_work(vi); flush_work(&vi->rx_mode_work); + flush_work(&vi->get_cvq); netif_tx_lock_bh(vi->dev); netif_device_detach(vi->dev); @@ -5610,6 +5776,45 @@ static const struct xdp_metadata_ops virtnet_xdp_metadata_ops = { .xmo_rx_hash = virtnet_xdp_rx_hash, }; +static void virtnet_del_coal_free_list(struct virtnet_info *vi) +{ + struct virtnet_coal_node *coal_node, *tmp; + + list_for_each_entry_safe(coal_node, tmp, &vi->coal_free_list, list) { + list_del(&coal_node->list); + kfree(coal_node); + } +} + +static int virtnet_init_coal_list(struct virtnet_info *vi) +{ + struct virtnet_coal_node *coal_node; + int batch_dim_nums; + int i; + + INIT_LIST_HEAD(&vi->coal_free_list); + mutex_init(&vi->coal_free_lock); + + INIT_LIST_HEAD(&vi->coal_wait_list); + mutex_init(&vi->coal_wait_lock); + + if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_VQ_NOTF_COAL)) + return 0; + + batch_dim_nums = min((unsigned int)vi->max_queue_pairs, + virtqueue_get_vring_size(vi->cvq) / 3); + for (i = 0; i < batch_dim_nums; i++) { + coal_node = kzalloc(sizeof(*coal_node), GFP_KERNEL); + if (!coal_node) { + virtnet_del_coal_free_list(vi); + return -ENOMEM; + } + list_add(&coal_node->list, &vi->coal_free_list); + } + + return 0; +} + static int virtnet_probe(struct virtio_device *vdev) { int i, err = -ENOMEM; @@ -5795,6 +6000,9 @@ static int virtnet_probe(struct virtio_device *vdev) if (err) goto free; + if (virtnet_init_coal_list(vi)) + goto free; + if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_NOTF_COAL)) { vi->intr_coal_rx.max_usecs = 0; vi->intr_coal_tx.max_usecs = 0; @@ -5836,6 +6044,7 @@ static int virtnet_probe(struct virtio_device *vdev) if (vi->has_rss || vi->has_rss_hash_report) virtnet_init_default_rss(vi); + INIT_WORK(&vi->get_cvq, virtnet_get_cvq_work); init_completion(&vi->completion); enable_rx_mode_work(vi); @@ -5965,11 +6174,14 @@ static void virtnet_remove(struct virtio_device *vdev) flush_work(&vi->config_work); disable_rx_mode_work(vi); flush_work(&vi->rx_mode_work); + flush_work(&vi->get_cvq); unregister_netdev(vi->dev); net_failover_destroy(vi->failover); + virtnet_del_coal_free_list(vi); + remove_vq_common(vi); free_netdev(vi->dev);
Currently, the control queue (ctrlq) handles commands synchronously, leading to increased delays for dim commands during multi-queue VM configuration and directly impacting dim performance. To address this, we are shifting to asynchronous processing of ctrlq's dim commands. Signed-off-by: Heng Qi <hengqi@linux.alibaba.com> --- drivers/net/virtio_net.c | 260 +++++++++++++++++++++++++++++++++++---- 1 file changed, 236 insertions(+), 24 deletions(-)