From:   Wenliang Wang <wangwenliang.1995@bytedance.com>
To:     mst@redhat.com, jasowang@redhat.com, davem@davemloft.net,
        kuba@kernel.org
Cc:     virtualization@lists.linux-foundation.org, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        Wenliang Wang <wangwenliang.1995@bytedance.com>
Subject: [PATCH] virtio_net: fix rx_drops stat for small pkts
Date:   Thu, 16 Dec 2021 11:11:35 +0800
Message-Id: <20211216031135.3182660-1-wangwenliang.1995@bytedance.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

We found the stat of rx drops for small pkts does not increment when
build_skb fail, it's not coherent with other mode's rx drops stat.

Signed-off-by: Wenliang Wang <wangwenliang.1995@bytedance.com>
---
 drivers/net/virtio_net.c | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 55db6a336f7e..b107835242ad 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -733,7 +733,7 @@ static struct sk_buff *receive_small(struct net_device *dev,
 		pr_debug("%s: rx error: len %u exceeds max size %d\n",
 			 dev->name, len, GOOD_PACKET_LEN);
 		dev->stats.rx_length_errors++;
-		goto err_len;
+		goto err;
 	}
 
 	if (likely(!vi->xdp_enabled)) {
@@ -825,10 +825,8 @@ static struct sk_buff *receive_small(struct net_device *dev,
 
 skip_xdp:
 	skb = build_skb(buf, buflen);
-	if (!skb) {
-		put_page(page);
+	if (!skb)
 		goto err;
-	}
 	skb_reserve(skb, headroom - delta);
 	skb_put(skb, len);
 	if (!xdp_prog) {
@@ -839,13 +837,12 @@ static struct sk_buff *receive_small(struct net_device *dev,
 	if (metasize)
 		skb_metadata_set(skb, metasize);
 
-err:
 	return skb;
 
 err_xdp:
 	rcu_read_unlock();
 	stats->xdp_drops++;
-err_len:
+err:
 	stats->drops++;
 	put_page(page);
 xdp_xmit:
-- 
2.30.2