When enable, a certain number of struct virtnet_xsk_hdr is allocated to
save the information of each packet and virtio hdr.This number is the
limit of the received module parameters.
When struct virtnet_xsk_hdr is used up, or the sq->vq->num_free of
virtio-net is too small, it will be considered that the device is busy.
* xsk_num_max: the xsk.hdr max num
* xsk_num_percent: the max hdr num be the percent of the virtio ring
size. The real xsk hdr num will the min of xsk_num_max and the percent
of the num of virtio ring
* xsk_budget: the budget for xsk run
Signed-off-by: Xuan Zhuo <xuanzhuo@xxxxxxxxxxxxxxxxx>
---
drivers/net/virtio_net.c | 97 ++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 97 insertions(+)
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 9013328..a62d456 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -22,10 +22,19 @@
#include <net/route.h>
#include <net/xdp.h>
#include <net/net_failover.h>
+#include <net/xdp_sock_drv.h>
static int napi_weight = NAPI_POLL_WEIGHT;
module_param(napi_weight, int, 0444);
+static int xsk_num_max = 1024;
+static int xsk_num_percent = 80;
+static int xsk_budget = 128;
+
+module_param(xsk_num_max, int, 0644);
+module_param(xsk_num_percent, int, 0644);
+module_param(xsk_budget, int, 0644);
+
static bool csum = true, gso = true, napi_tx = true;
module_param(csum, bool, 0444);
module_param(gso, bool, 0444);
@@ -149,6 +158,15 @@ struct send_queue {
struct virtnet_sq_stats stats;
struct napi_struct napi;
+
+ struct {
+ struct xsk_buff_pool __rcu *pool;
+ struct virtnet_xsk_hdr __rcu *hdr;
+
+ u64 hdr_con;
+ u64 hdr_pro;
+ u64 hdr_n;
+ } xsk;
};
/* Internal representation of a receive virtqueue */
@@ -2540,11 +2558,90 @@ static int virtnet_xdp_set(struct net_device *dev, struct bpf_prog *prog,
return err;
}
+static int virtnet_xsk_pool_enable(struct net_device *dev,
+ struct xsk_buff_pool *pool,
+ u16 qid)
+{
+ struct virtnet_info *vi = netdev_priv(dev);
+ struct send_queue *sq = &vi->sq[qid];
+ struct virtnet_xsk_hdr *hdr;
+ int n, ret = 0;
+
+ if (qid >= dev->real_num_rx_queues || qid >= dev->real_num_tx_queues)
+ return -EINVAL;
+
+ if (qid >= vi->curr_queue_pairs)
+ return -EINVAL;
+
+ rcu_read_lock();
+
+ ret = -EBUSY;
+ if (rcu_dereference(sq->xsk.pool))
+ goto end;
+
+ /* check last xsk wait for hdr been free */
+ if (rcu_dereference(sq->xsk.hdr))
+ goto end;
+
+ n = virtqueue_get_vring_size(sq->vq);
+ n = min(xsk_num_max, n * (xsk_num_percent % 100) / 100);
+
+ ret = -ENOMEM;
+ hdr = kcalloc(n, sizeof(struct virtnet_xsk_hdr), GFP_ATOMIC);
+ if (!hdr)
+ goto end;
+
+ memset(&sq->xsk, 0, sizeof(sq->xsk));
+
+ sq->xsk.hdr_pro = n;
+ sq->xsk.hdr_n = n;
+
+ rcu_assign_pointer(sq->xsk.pool, pool);
+ rcu_assign_pointer(sq->xsk.hdr, hdr);
+
+ ret = 0;
+end:
+ rcu_read_unlock();
+
+ return ret;
+}
+
+static int virtnet_xsk_pool_disable(struct net_device *dev, u16 qid)
+{
+ struct virtnet_info *vi = netdev_priv(dev);
+ struct send_queue *sq = &vi->sq[qid];
+ struct virtnet_xsk_hdr *hdr = NULL;
+
+ if (qid >= dev->real_num_rx_queues || qid >= dev->real_num_tx_queues)
+ return -EINVAL;
+
+ if (qid >= vi->curr_queue_pairs)
+ return -EINVAL;
+
+ rcu_assign_pointer(sq->xsk.pool, NULL);
+
+ if (sq->xsk.hdr_pro - sq->xsk.hdr_con == sq->xsk.hdr_n)
+ hdr = rcu_replace_pointer(sq->xsk.hdr, hdr, true);
+
+ synchronize_rcu(); /* Sync with the XSK wakeup and with NAPI. */
+
+ kfree(hdr);
+
+ return 0;
+}
+
static int virtnet_xdp(struct net_device *dev, struct netdev_bpf *xdp)
{
switch (xdp->command) {
case XDP_SETUP_PROG:
return virtnet_xdp_set(dev, xdp->prog, xdp->extack);
+ case XDP_SETUP_XSK_POOL:
+ xdp->xsk.need_dma = false;
+ if (xdp->xsk.pool)
+ return virtnet_xsk_pool_enable(dev, xdp->xsk.pool,
+ xdp->xsk.queue_id);
+ else
+ return virtnet_xsk_pool_disable(dev, xdp->xsk.queue_id);
default:
return -EINVAL;
}
--
1.8.3.1
