From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Dumazet via iovisor-dev Subject: Re: [PATCH RFC 11/11] net/mlx5e: XDP TX xmit more Date: Wed, 07 Sep 2016 11:19:06 -0700 Message-ID: <1473272346.10725.73.camel@edumazet-glaptop3.roam.corp.google.com> References: <1473252152-11379-1-git-send-email-saeedm@mellanox.com> <1473252152-11379-12-git-send-email-saeedm@mellanox.com> <1473259302.10725.31.camel@edumazet-glaptop3.roam.corp.google.com> <1473262379.10725.42.camel@edumazet-glaptop3.roam.corp.google.com> Reply-To: Eric Dumazet Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: Linux Netdev List , iovisor-dev , Jamal Hadi Salim , Saeed Mahameed , Eric Dumazet , Tom Herbert To: Saeed Mahameed Return-path: In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: iovisor-dev-bounces-9jONkmmOlFHEE9lA1F8Ukti2O/JbrIOy@public.gmane.org Errors-To: iovisor-dev-bounces-9jONkmmOlFHEE9lA1F8Ukti2O/JbrIOy@public.gmane.org List-Id: netdev.vger.kernel.org On Wed, 2016-09-07 at 19:57 +0300, Saeed Mahameed wrote: > Jesper has a similar Idea to make the qdisc think it is under > pressure, when the device > TX ring is idle most of the time, i think his idea can come in handy here. > I am not fully involved in the details, maybe he can elaborate more. > > But if it works, it will be transparent to napi, and xmit more will > happen by design. I do not think qdisc is relevant here. Right now, skb->xmit_more is set only by qdisc layer (and pktgen tool), because only this layer can know if more packets are to come. What I am saying is that regardless of skb->xmit_more being set or not, (for example if no qdisc is even used) a NAPI driver can arm a bit asking the doorbell being sent at the end of NAPI. I am not saying this must be done, only that the idea could be extended to non XDP world, if we care enough.