From: Eric Dumazet <eric.duma...@gmail.com> Date: Wed, 22 Apr 2015 12:12:20 -0700
> On Wed, 2015-04-22 at 14:50 -0400, David Miller wrote: >> From: Eric Dumazet <eric.duma...@gmail.com> >> Date: Wed, 22 Apr 2015 11:39:27 -0700 >> >> > Note that in the unlikely case skb can not be allocated, >> > if an already transmitted packet is in the write queue, we also can OR >> > the FIN flag on it, and rely on normal rtx to deliver this FIN later. >> > >> > I'll cook a patch when net-next reopens. >> >> Hmmm, we already check for something like this at the beginning of >> tcp_send_fin(), I know because I added that piece of code 15+ years >> ago :-) >> >> Or are you suggesting something slightly different? > > > The existing test does the OR only if there is an unsent frame in the > write queue. > > Because if the frame present in write queue was already sent, we prefer > cooking a fresh skb to be able to send it right now (disabling Nagle > checks) > > So, in the case we cannot allocate the skb, we can still add the FIN > flag, but not push any frame right now. > > FIN will be sent later, because incoming ACK or rtx will eventually send > it. > > This sounds better than not sending FIN at all. Ok, that makes a lot of sense. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
