Eric Dumazet <eric.duma...@gmail.com> wrote: > On Mon, 2016-06-06 at 13:42 +0200, Florian Westphal wrote: > > Jamal Hadi Salim <j...@mojatatu.com> wrote: > > > BTW, returning NET_XMIT_CN could be confusing to tcp; > > > it does not mean that the packet that we are getting return > > > code for was dropped; it could mean _another_ packet in > > > the queue was dropped. > > > > Yes, but we currently conceal NET_XMIT_CN from upper layer (tcp) > > via the net_xmit_* macros: > > > > #define net_xmit_eval(e) ((e) == NET_XMIT_CN ? 0 : (e)) > > #define net_xmit_errno(e) ((e) != NET_XMIT_CN ? -ENOBUFS : 0) > > > > Might be worth changing this so tcp reduces cwnd in _CN case too. > > It always had been the case. > > tcp_transmit_skb() calls tcp_enter_cwr(), unless someone broke this.
No, you're right. We hide error in ip_send_skb but that function is not used in tcp case. So all is good here.
