From: Vedang Patel <vedang.pa...@intel.com> Date: Tue, 25 Jun 2019 15:07:11 -0700
> Currently, we are seeing packets being transmitted outside their > timeslices. We can confirm that the packets are being dequeued at the right > time. So, the delay is induced after the packet is dequeued, because > taprio, without any offloading, has no control of when a packet is actually > transmitted. > > In order to solve this, we are making use of the txtime feature provided by > ETF qdisc. Hardware offloading needs to be supported by the ETF qdisc in > order to take advantage of this feature. The taprio qdisc will assign > txtime (in skb->tstamp) for all the packets which do not have the txtime > allocated via the SO_TXTIME socket option. For the packets which already > have SO_TXTIME set, taprio will validate whether the packet will be > transmitted in the correct interval. > > In order to support this, the following parameters have been added: > - flags (taprio): This is added in order to support different offloading > modes which will be added in the future. > - txtime-delay (taprio): This indicates the minimum time it will take for > the packet to hit the wire after it reaches taprio_enqueue(). This is > useful in determining whether we can transmit the packet in the remaining > time if the gate corresponding to the packet is currently open. > - skip_skb_check (ETF): ETF currently drops any packet which does not have > the SO_TXTIME socket option set. This check can be skipped by specifying > this option. ... Series applied, thanks.
