From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vladimir Oltean Date: Mon, 28 Jun 2021 09:20:03 +0000 Subject: [Intel-wired-lan] [PATCH net-next v4 11/12] igc: Check incompatible configs for Frame Preemption In-Reply-To: <20210626003314.3159402-12-vinicius.gomes@intel.com> References: <20210626003314.3159402-1-vinicius.gomes@intel.com> <20210626003314.3159402-12-vinicius.gomes@intel.com> Message-ID: <20210628092003.bribdjfaxwnpdt5f@skbuf> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: intel-wired-lan@osuosl.org List-ID: On Fri, Jun 25, 2021 at 05:33:13PM -0700, Vinicius Costa Gomes wrote: > Frame Preemption and LaunchTime cannot be enabled on the same queue. > If that situation happens, emit an error to the user, and log the > error. > > Signed-off-by: Vinicius Costa Gomes > --- This is a very interesting limitation, considering the fact that much of the frame preemption validation that I did was in conjunction with tc-etf and SO_TXTIME (send packets on 2 queues, one preemptible and one express, and compare the TX timestamps of the express packets with their scheduled TX times). The base-time offset between the ET and the PT packets is varied in small increments in the order of 20 ns or so. If this is not possible with hardware driven by igc, how do you know it works properly? :)