virtio-net: support dim profile fine-tuning

Virtio-net has different types of back-end device implementations.
In order to effectively optimize the dim library's gains for different
device implementations, let's use the new interface params to
initialize and query dim results from a customized profile list.

Signed-off-by: Heng Qi <hengqi@linux.alibaba.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20240621101353.107425-6-hengqi@linux.alibaba.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index f212977513107137bcd6219b184e9124b4e9c649..0b4747e81464fbabb5ff6fdf62bb894cc58ff4b3 100644 (file)
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -2469,6 +2469,13 @@ err_xdp_reg_mem_model:
        return err;
 }
 
+static void virtnet_cancel_dim(struct virtnet_info *vi, struct dim *dim)
+{
+       if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_VQ_NOTF_COAL))
+               return;
+       net_dim_work_cancel(dim);
+}
+
 static int virtnet_open(struct net_device *dev)
 {
        struct virtnet_info *vi = netdev_priv(dev);
@@ -2495,7 +2502,7 @@ err_enable_qp:
 
        for (i--; i >= 0; i--) {
                virtnet_disable_queue_pair(vi, i);
-               cancel_work_sync(&vi->rq[i].dim.work);
+               virtnet_cancel_dim(vi, &vi->rq[i].dim);
        }
 
        return err;
@@ -2671,7 +2678,7 @@ static int virtnet_rx_resize(struct virtnet_info *vi,
 
        if (running) {
                napi_disable(&rq->napi);
-               cancel_work_sync(&rq->dim.work);
+               virtnet_cancel_dim(vi, &rq->dim);
        }
 
        err = virtqueue_resize(rq->vq, ring_num, virtnet_rq_unmap_free_buf);
@@ -2932,7 +2939,7 @@ static int virtnet_close(struct net_device *dev)
 
        for (i = 0; i < vi->max_queue_pairs; i++) {
                virtnet_disable_queue_pair(vi, i);
-               cancel_work_sync(&vi->rq[i].dim.work);
+               virtnet_cancel_dim(vi, &vi->rq[i].dim);
        }
 
        return 0;
@@ -4458,7 +4465,7 @@ static void virtnet_rx_dim_work(struct work_struct *work)
        if (!rq->dim_enabled)
                goto out;
 
-       update_moder = net_dim_get_rx_moderation(dim->mode, dim->profile_ix);
+       update_moder = net_dim_get_rx_irq_moder(dev, dim);
        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,
@@ -5158,6 +5165,36 @@ static void virtnet_tx_timeout(struct net_device *dev, unsigned int txqueue)
                   jiffies_to_usecs(jiffies - READ_ONCE(txq->trans_start)));
 }
 
+static int virtnet_init_irq_moder(struct virtnet_info *vi)
+{
+       u8 profile_flags = 0, coal_flags = 0;
+       int ret, i;
+
+       profile_flags |= DIM_PROFILE_RX;
+       coal_flags |= DIM_COALESCE_USEC | DIM_COALESCE_PKTS;
+       ret = net_dim_init_irq_moder(vi->dev, profile_flags, coal_flags,
+                                    DIM_CQ_PERIOD_MODE_START_FROM_EQE,
+                                    0, virtnet_rx_dim_work, NULL);
+
+       if (ret)
+               return ret;
+
+       for (i = 0; i < vi->max_queue_pairs; i++)
+               net_dim_setting(vi->dev, &vi->rq[i].dim, false);
+
+       return 0;
+}
+
+static void virtnet_free_irq_moder(struct virtnet_info *vi)
+{
+       if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_VQ_NOTF_COAL))
+               return;
+
+       rtnl_lock();
+       net_dim_free_irq_moder(vi->dev);
+       rtnl_unlock();
+}
+
 static const struct net_device_ops virtnet_netdev = {
        .ndo_open            = virtnet_open,
        .ndo_stop            = virtnet_close,
@@ -5437,9 +5474,6 @@ static int virtnet_alloc_queues(struct virtnet_info *vi)
                                         virtnet_poll_tx,
                                         napi_tx ? napi_weight : 0);
 
-               INIT_WORK(&vi->rq[i].dim.work, virtnet_rx_dim_work);
-               vi->rq[i].dim.mode = DIM_CQ_PERIOD_MODE_START_FROM_EQE;
-
                sg_init_table(vi->rq[i].sg, ARRAY_SIZE(vi->rq[i].sg));
                ewma_pkt_len_init(&vi->rq[i].mrg_avg_pkt_len);
                sg_init_table(vi->sq[i].sg, ARRAY_SIZE(vi->sq[i].sg));
@@ -5868,6 +5902,10 @@ static int virtnet_probe(struct virtio_device *vdev)
                for (i = 0; i < vi->max_queue_pairs; i++)
                        if (vi->sq[i].napi.weight)
                                vi->sq[i].intr_coal.max_packets = 1;
+
+               err = virtnet_init_irq_moder(vi);
+               if (err)
+                       goto free;
        }
 
 #ifdef CONFIG_SYSFS
@@ -6019,6 +6057,8 @@ static void virtnet_remove(struct virtio_device *vdev)
        disable_rx_mode_work(vi);
        flush_work(&vi->rx_mode_work);
 
+       virtnet_free_irq_moder(vi);
+
        unregister_netdev(vi->dev);
 
        net_failover_destroy(vi->failover);