By comparing the traffic information in the complete napi processes, let the virtio-net driver automatically adjust the coalescing moderation parameters of each receive queue. Signed-off-by: Heng Qi <hengqi@xxxxxxxxxxxxxxxxx> --- v2->v3: - Some minor modifications. v1->v2: - Improved the judgment of dim switch conditions. - Cancel the work when vq reset. drivers/net/virtio_net.c | 191 ++++++++++++++++++++++++++++++++++----- 1 file changed, 169 insertions(+), 22 deletions(-) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index 69fe09e99b3c..bc32d5aae005 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -19,6 +19,7 @@ #include <linux/average.h> #include <linux/filter.h> #include <linux/kernel.h> +#include <linux/dim.h> #include <net/route.h> #include <net/xdp.h> #include <net/net_failover.h> @@ -172,6 +173,17 @@ struct receive_queue { struct virtnet_rq_stats stats; + /* The number of rx notifications */ + u16 calls; + + /* Is dynamic interrupt moderation enabled? */ + bool dim_enabled; + + /* Dynamic Interrupt Moderation */ + struct dim dim; + + u32 packets_in_napi; + struct virtnet_interrupt_coalesce intr_coal; /* Chain pages by the private ptr. */ @@ -305,6 +317,9 @@ struct virtnet_info { u8 duplex; u32 speed; + /* Is rx dynamic interrupt moderation enabled? */ + bool rx_dim_enabled; + /* Interrupt coalescing settings */ struct virtnet_interrupt_coalesce intr_coal_tx; struct virtnet_interrupt_coalesce intr_coal_rx; @@ -2001,6 +2016,7 @@ static void skb_recv_done(struct virtqueue *rvq) struct virtnet_info *vi = rvq->vdev->priv; struct receive_queue *rq = &vi->rq[vq2rxq(rvq)]; + rq->calls++; virtqueue_napi_schedule(&rq->napi, rvq); } @@ -2141,6 +2157,26 @@ static void virtnet_poll_cleantx(struct receive_queue *rq) } } +static void virtnet_rx_dim_work(struct work_struct *work); + +static void virtnet_rx_dim_update(struct virtnet_info *vi, struct receive_queue *rq) +{ + struct dim_sample cur_sample = {}; + + if (!rq->packets_in_napi) + return; + + u64_stats_update_begin(&rq->stats.syncp); + dim_update_sample(rq->calls, + u64_stats_read(&rq->stats.packets), + u64_stats_read(&rq->stats.bytes), + &cur_sample); + u64_stats_update_end(&rq->stats.syncp); + + net_dim(&rq->dim, cur_sample); + rq->packets_in_napi = 0; +} + static int virtnet_poll(struct napi_struct *napi, int budget) { struct receive_queue *rq = @@ -2149,17 +2185,22 @@ static int virtnet_poll(struct napi_struct *napi, int budget) struct send_queue *sq; unsigned int received; unsigned int xdp_xmit = 0; + bool napi_complete; virtnet_poll_cleantx(rq); received = virtnet_receive(rq, budget, &xdp_xmit); + rq->packets_in_napi += received; if (xdp_xmit & VIRTIO_XDP_REDIR) xdp_do_flush(); /* Out of packets? */ - if (received < budget) - virtqueue_napi_complete(napi, rq->vq, received); + if (received < budget) { + napi_complete = virtqueue_napi_complete(napi, rq->vq, received); + if (napi_complete && rq->dim_enabled) + virtnet_rx_dim_update(vi, rq); + } if (xdp_xmit & VIRTIO_XDP_TX) { sq = virtnet_xdp_get_sq(vi); @@ -2179,6 +2220,7 @@ static void virtnet_disable_queue_pair(struct virtnet_info *vi, int qp_index) virtnet_napi_tx_disable(&vi->sq[qp_index].napi); napi_disable(&vi->rq[qp_index].napi); xdp_rxq_info_unreg(&vi->rq[qp_index].xdp_rxq); + cancel_work_sync(&vi->rq[qp_index].dim.work); } static int virtnet_enable_queue_pair(struct virtnet_info *vi, int qp_index) @@ -2196,6 +2238,9 @@ static int virtnet_enable_queue_pair(struct virtnet_info *vi, int qp_index) if (err < 0) goto err_xdp_reg_mem_model; + INIT_WORK(&vi->rq[qp_index].dim.work, virtnet_rx_dim_work); + vi->rq[qp_index].dim.mode = DIM_CQ_PERIOD_MODE_START_FROM_EQE; + virtnet_napi_enable(vi->rq[qp_index].vq, &vi->rq[qp_index].napi); virtnet_napi_tx_enable(vi, vi->sq[qp_index].vq, &vi->sq[qp_index].napi); @@ -2393,8 +2438,10 @@ static int virtnet_rx_resize(struct virtnet_info *vi, qindex = rq - vi->rq; - if (running) + if (running) { napi_disable(&rq->napi); + cancel_work_sync(&rq->dim.work); + } err = virtqueue_resize(rq->vq, ring_num, virtnet_rq_free_unused_buf); if (err) @@ -2403,8 +2450,10 @@ static int virtnet_rx_resize(struct virtnet_info *vi, if (!try_fill_recv(vi, rq, GFP_KERNEL)) schedule_delayed_work(&vi->refill, 0); - if (running) + if (running) { + INIT_WORK(&rq->dim.work, virtnet_rx_dim_work); virtnet_napi_enable(rq->vq, &rq->napi); + } return err; } @@ -3341,24 +3390,55 @@ static int virtnet_send_tx_notf_coal_cmds(struct virtnet_info *vi, static int virtnet_send_rx_notf_coal_cmds(struct virtnet_info *vi, struct ethtool_coalesce *ec) { + bool rx_ctrl_dim_on = !!ec->use_adaptive_rx_coalesce; + bool update = false, switch_dim; struct scatterlist sgs_rx; int i; - vi->ctrl->coal_rx.rx_usecs = cpu_to_le32(ec->rx_coalesce_usecs); - vi->ctrl->coal_rx.rx_max_packets = cpu_to_le32(ec->rx_max_coalesced_frames); - sg_init_one(&sgs_rx, &vi->ctrl->coal_rx, sizeof(vi->ctrl->coal_rx)); - - if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_NOTF_COAL, - VIRTIO_NET_CTRL_NOTF_COAL_RX_SET, - &sgs_rx)) - return -EINVAL; + switch_dim = rx_ctrl_dim_on != vi->rx_dim_enabled; + if (switch_dim) { + if (rx_ctrl_dim_on) { + if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_VQ_NOTF_COAL)) { + vi->rx_dim_enabled = true; + for (i = 0; i < vi->max_queue_pairs; i++) + vi->rq[i].dim_enabled = true; + } else { + return -EOPNOTSUPP; + } + } else { + vi->rx_dim_enabled = false; + for (i = 0; i < vi->max_queue_pairs; i++) + vi->rq[i].dim_enabled = false; + } + } else { + if (ec->rx_coalesce_usecs != vi->intr_coal_rx.max_usecs || + ec->rx_max_coalesced_frames != vi->intr_coal_rx.max_packets) + update = true; - /* Save parameters */ - vi->intr_coal_rx.max_usecs = ec->rx_coalesce_usecs; - vi->intr_coal_rx.max_packets = ec->rx_max_coalesced_frames; - for (i = 0; i < vi->max_queue_pairs; i++) { - vi->rq[i].intr_coal.max_usecs = ec->rx_coalesce_usecs; - vi->rq[i].intr_coal.max_packets = ec->rx_max_coalesced_frames; + if (vi->rx_dim_enabled) { + if (update) + return -EINVAL; + } else { + /* Since the per-queue coalescing params can be set, + * we need apply the global new params even if they + * are not updated. + */ + vi->ctrl->coal_rx.rx_usecs = cpu_to_le32(ec->rx_coalesce_usecs); + vi->ctrl->coal_rx.rx_max_packets = cpu_to_le32(ec->rx_max_coalesced_frames); + sg_init_one(&sgs_rx, &vi->ctrl->coal_rx, sizeof(vi->ctrl->coal_rx)); + + if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_NOTF_COAL, + VIRTIO_NET_CTRL_NOTF_COAL_RX_SET, + &sgs_rx)) + return -EINVAL; + + vi->intr_coal_rx.max_usecs = ec->rx_coalesce_usecs; + vi->intr_coal_rx.max_packets = ec->rx_max_coalesced_frames; + for (i = 0; i < vi->max_queue_pairs; i++) { + vi->rq[i].intr_coal.max_usecs = ec->rx_coalesce_usecs; + vi->rq[i].intr_coal.max_packets = ec->rx_max_coalesced_frames; + } + } } return 0; @@ -3380,15 +3460,54 @@ static int virtnet_send_notf_coal_cmds(struct virtnet_info *vi, return 0; } +static int virtnet_send_rx_notf_coal_vq_cmds(struct virtnet_info *vi, + struct ethtool_coalesce *ec, + u16 queue) +{ + bool rx_ctrl_dim_on = !!ec->use_adaptive_rx_coalesce; + bool cur_rx_dim = vi->rq[queue].dim_enabled; + bool update = false, switch_dim; + u32 max_usecs, max_packets; + int err; + + switch_dim = rx_ctrl_dim_on != cur_rx_dim; + if (switch_dim) { + if (rx_ctrl_dim_on) + vi->rq[queue].dim_enabled = true; + else + vi->rq[queue].dim_enabled = false; + } else { + max_usecs = vi->rq[queue].intr_coal.max_usecs; + max_packets = vi->rq[queue].intr_coal.max_packets; + if (ec->rx_coalesce_usecs != max_usecs || + ec->rx_max_coalesced_frames != max_packets) + update = true; + + if (cur_rx_dim) { + if (update) + return -EINVAL; + } else { + if (!update) + return 0; + + err = virtnet_send_rx_ctrl_coal_vq_cmd(vi, queue, + ec->rx_coalesce_usecs, + ec->rx_max_coalesced_frames); + if (err) + return err; + } + } + + return 0; +} + static int virtnet_send_notf_coal_vq_cmds(struct virtnet_info *vi, struct ethtool_coalesce *ec, u16 queue) { int err; - err = virtnet_send_rx_ctrl_coal_vq_cmd(vi, queue, - ec->rx_coalesce_usecs, - ec->rx_max_coalesced_frames); + err = virtnet_send_rx_notf_coal_vq_cmds(vi, ec, queue); if (err) return err; @@ -3401,6 +3520,32 @@ static int virtnet_send_notf_coal_vq_cmds(struct virtnet_info *vi, return 0; } +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 dim_cq_moder update_moder; + int qnum = rq - vi->rq, err; + + update_moder = net_dim_get_rx_moderation(dim->mode, dim->profile_ix); + if (update_moder.usec != vi->rq[qnum].intr_coal.max_usecs || + update_moder.pkts != vi->rq[qnum].intr_coal.max_packets) { + rtnl_lock(); + 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, (int)(rq - vi->rq)); + rtnl_unlock(); + } + + dim->state = DIM_START_MEASURE; +} + static int virtnet_coal_params_supported(struct ethtool_coalesce *ec) { /* usecs coalescing is supported only if VIRTIO_NET_F_NOTF_COAL @@ -3482,6 +3627,7 @@ static int virtnet_get_coalesce(struct net_device *dev, ec->tx_coalesce_usecs = vi->intr_coal_tx.max_usecs; ec->tx_max_coalesced_frames = vi->intr_coal_tx.max_packets; ec->rx_max_coalesced_frames = vi->intr_coal_rx.max_packets; + ec->use_adaptive_rx_coalesce = vi->rx_dim_enabled; } else { ec->rx_max_coalesced_frames = 1; @@ -3539,6 +3685,7 @@ static int virtnet_get_per_queue_coalesce(struct net_device *dev, ec->tx_coalesce_usecs = vi->sq[queue].intr_coal.max_usecs; ec->tx_max_coalesced_frames = vi->sq[queue].intr_coal.max_packets; ec->rx_max_coalesced_frames = vi->rq[queue].intr_coal.max_packets; + ec->use_adaptive_rx_coalesce = vi->rq[queue].dim_enabled; } else { ec->rx_max_coalesced_frames = 1; @@ -3664,7 +3811,7 @@ static int virtnet_set_rxnfc(struct net_device *dev, struct ethtool_rxnfc *info) static const struct ethtool_ops virtnet_ethtool_ops = { .supported_coalesce_params = ETHTOOL_COALESCE_MAX_FRAMES | - ETHTOOL_COALESCE_USECS, + ETHTOOL_COALESCE_USECS | ETHTOOL_COALESCE_USE_ADAPTIVE_RX, .get_drvinfo = virtnet_get_drvinfo, .get_link = ethtool_op_get_link, .get_ringparam = virtnet_get_ringparam, -- 2.19.1.6.gb485710b