diff options
| author | Li RongQing <lirongqing@baidu.com> | 2021-10-09 17:32:43 +0800 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2021-10-10 11:31:09 +0100 |
| commit | 6213f07cb542c9651ba614e784bf58ed41354936 (patch) | |
| tree | 687df6e5bbb9336fb067f5392bff0cb5c40e5bb6 /drivers/net/virtio_net.c | |
| parent | c0288ae8e6bd402785360de5bbc94ded770af000 (diff) | |
virtio_net: skip RCU read lock by checking xdp_enabled of vi
networking benchmark shows that __rcu_read_lock and
__rcu_read_unlock takes some cpu cycles, and we can avoid
calling them partially in virtio rx path by check xdp_enabled
of vi, and xdp is disabled most of time
Signed-off-by: Li RongQing <lirongqing@baidu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/virtio_net.c')
| -rw-r--r-- | drivers/net/virtio_net.c | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index 2ed49884565f..74d2be438180 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -734,6 +734,12 @@ static struct sk_buff *receive_small(struct net_device *dev, dev->stats.rx_length_errors++; goto err_len; } + + if (likely(!vi->xdp_enabled)) { + xdp_prog = NULL; + goto skip_xdp; + } + rcu_read_lock(); xdp_prog = rcu_dereference(rq->xdp_prog); if (xdp_prog) { @@ -816,6 +822,7 @@ static struct sk_buff *receive_small(struct net_device *dev, } rcu_read_unlock(); +skip_xdp: skb = build_skb(buf, buflen); if (!skb) { put_page(page); @@ -897,6 +904,12 @@ static struct sk_buff *receive_mergeable(struct net_device *dev, dev->stats.rx_length_errors++; goto err_skb; } + + if (likely(!vi->xdp_enabled)) { + xdp_prog = NULL; + goto skip_xdp; + } + rcu_read_lock(); xdp_prog = rcu_dereference(rq->xdp_prog); if (xdp_prog) { @@ -1024,6 +1037,7 @@ static struct sk_buff *receive_mergeable(struct net_device *dev, } rcu_read_unlock(); +skip_xdp: head_skb = page_to_skb(vi, rq, page, offset, len, truesize, !xdp_prog, metasize, headroom); curr_skb = head_skb; |