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author | Heng Qi <hengqi@linux.alibaba.com> | 2023-10-08 14:27:39 +0800 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2023-10-11 07:13:50 +0100 |
commit | 3014a0d54820d25c3dc66657bcc19013f2338760 (patch) | |
tree | 06137282149134a11ad7322e7b78dec8a5eb48ff /drivers | |
parent | e5f061d5e340fefc663cacfe8f42f149d55bdb53 (diff) | |
download | linux-3014a0d54820d25c3dc66657bcc19013f2338760.tar.gz linux-3014a0d54820d25c3dc66657bcc19013f2338760.tar.bz2 linux-3014a0d54820d25c3dc66657bcc19013f2338760.zip |
virtio-net: initially change the value of tx-frames
Background:
1. Commit 0c465be183c7 ("virtio_net: ethtool tx napi configuration") uses
tx-frames to toggle napi_tx (0 off and 1 on) if notification coalescing
is not supported.
2. Commit 31c03aef9bc2 ("virtio_net: enable napi_tx by default") enables
napi_tx for all txqs by default.
Status:
When virtio-net supports notification coalescing, after initialization,
tx-frames is 0 and napi_tx is true.
Problem:
When the user only wants to set rx coalescing params using
ethtool -C eth0 rx-usecs 10, or
ethtool -Q eth0 queue_mask 0x1 -C rx-usecs 10,
these cmds will carry tx-frames as 0, causing the napi_tx switching condition
is satisfied. Then the user gets:
netlink error: Device or resource busy.
The same happens when trying to set rx-frames, adaptive_rx, adaptive_tx...
How to fix:
When notification coalescing feature is negotiated, initially make the
value of tx-frames to be consistent with napi_tx.
For compatibility with the past, it is still supported to use tx-frames
to toggle napi_tx.
Reported-by: Xiaoming Zhao <zxm377917@alibaba-inc.com>
Signed-off-by: Heng Qi <hengqi@linux.alibaba.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/net/virtio_net.c | 28 |
1 files changed, 21 insertions, 7 deletions
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index 1ed6bcc4cbb1..35dc978def77 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -4442,13 +4442,6 @@ static int virtnet_probe(struct virtio_device *vdev) dev->xdp_features |= NETDEV_XDP_ACT_RX_SG; } - 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; - vi->intr_coal_tx.max_packets = 0; - vi->intr_coal_rx.max_packets = 0; - } - if (virtio_has_feature(vdev, VIRTIO_NET_F_HASH_REPORT)) vi->has_rss_hash_report = true; @@ -4523,6 +4516,27 @@ static int virtnet_probe(struct virtio_device *vdev) if (err) 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; + vi->intr_coal_rx.max_packets = 0; + + /* Keep the default values of the coalescing parameters + * aligned with the default napi_tx state. + */ + if (vi->sq[0].napi.weight) + vi->intr_coal_tx.max_packets = 1; + else + vi->intr_coal_tx.max_packets = 0; + } + + if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_VQ_NOTF_COAL)) { + /* The reason is the same as VIRTIO_NET_F_NOTF_COAL. */ + for (i = 0; i < vi->max_queue_pairs; i++) + if (vi->sq[i].napi.weight) + vi->sq[i].intr_coal.max_packets = 1; + } + #ifdef CONFIG_SYSFS if (vi->mergeable_rx_bufs) dev->sysfs_rx_queue_group = &virtio_net_mrg_rx_group; |