Re: [PATCH net-next 05/11] tuntap: tweak on the path of non-xdp case in tun_build_skb()
From: "Michael S. Tsirkin" <mst@redhat.com>
Date: 2018-09-06 17:16:21
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On Thu, Sep 06, 2018 at 12:05:20PM +0800, Jason Wang wrote:
If we're sure not to go native XDP, there's no need for several things like bh and rcu stuffs. Signed-off-by: Jason Wang <redacted>
True...
quoted hunk ↗ jump to hunk
--- drivers/net/tun.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-)diff --git a/drivers/net/tun.c b/drivers/net/tun.c index f8cdcfa392c3..389aa0727cc6 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c@@ -1675,10 +1675,12 @@ static struct sk_buff *tun_build_skb(struct tun_struct *tun, * of xdp_prog above, this should be rare and for simplicity * we do XDP on skb in case the headroom is not enough. */ - if (hdr->gso_type || !xdp_prog) + if (hdr->gso_type || !xdp_prog) { *skb_xdp = 1; - else - *skb_xdp = 0; + goto build; + } + + *skb_xdp = 0; local_bh_disable(); rcu_read_lock();@@ -1724,6 +1726,7 @@ static struct sk_buff *tun_build_skb(struct tun_struct *tun, rcu_read_unlock(); local_bh_enable(); +build:
But this is spaghetti code. Please just put common code into functions and call them, don't goto.
skb = build_skb(buf, buflen);
if (!skb) {
skb = ERR_PTR(-ENOMEM);
--
2.17.1