On 04/11/2017 10:48 AM, Joao Pinto wrote: > > Hi Niklas, > > Às 7:33 PM de 4/10/2017, Niklas Cassel escreveu: >> From: Niklas Cassel <niklas.cas...@axis.com> >> >> Field FL/TPL in register TDES3 is not correctly set on GMAC4. >> TX appears to be functional on GMAC 4.10a even if this field is not set, >> however, to avoid relying on undefined behavior, set the length in TDES3. >> >> The field has a different meaning depending on if the TSE bit in TDES3 >> is set or not (TSO). However, regardless of the TSE bit, the field is >> not optional. The field is already set correctly when the TSE bit is set. >> >> Since there is no limit for the number of descriptors that can be >> used for a single packet, the field should be set to the sum of >> the buffers contained in: >> [<desc with First Descriptor bit set> ... <desc n> ... >> <desc with Last Descriptor bit set>], which should be equal to skb->len. >> >> Signed-off-by: Niklas Cassel <niklas.cas...@axis.com> > > Sounds fine to me. Did you check for performance improvement? Thanks. >
Hello Joao, I could not see any difference with 1 TCP stream in iperf3 Without the patch: # ./iperf3-armhf -c 192.168.0.1 Connecting to host 192.168.0.1, port 5201 [ 4] local 192.168.0.105 port 51878 connected to 192.168.0.1 port 5201 [ 23.486426] random: fast init done [ ID] Interval Transfer Bandwidth Retr Cwnd [ 4] 0.00-1.00 sec 61.7 MBytes 517 Mbits/sec 0 294 KBytes [ 4] 1.00-2.00 sec 61.3 MBytes 515 Mbits/sec 0 294 KBytes [ 26.043850] random: crng init done [ 4] 2.00-3.00 sec 61.4 MBytes 515 Mbits/sec 0 294 KBytes [ 4] 3.00-4.00 sec 61.0 MBytes 512 Mbits/sec 0 294 KBytes [ 4] 4.00-5.00 sec 61.5 MBytes 516 Mbits/sec 0 294 KBytes [ 4] 5.00-6.00 sec 61.2 MBytes 514 Mbits/sec 0 294 KBytes [ 4] 6.00-7.00 sec 61.5 MBytes 516 Mbits/sec 0 294 KBytes [ 4] 7.00-8.00 sec 61.4 MBytes 515 Mbits/sec 0 294 KBytes [ 4] 8.00-9.00 sec 61.2 MBytes 514 Mbits/sec 0 294 KBytes [ 4] 9.00-10.00 sec 61.3 MBytes 514 Mbits/sec 0 294 KBytes - - - - - - - - - - - - - - - - - - - - - - - - - [ ID] Interval Transfer Bandwidth Retr [ 4] 0.00-10.00 sec 614 MBytes 515 Mbits/sec 0 sender [ 4] 0.00-10.00 sec 613 MBytes 514 Mbits/sec receiver With the patch: # ./iperf3-armhf -c 192.168.0.1 Connecting to host 192.168.0.1, port 5201 [ 4] local 192.168.0.105 port 37696 connected to 192.168.0.1 port 5201 [ 85.266262] random: fast init done [ ID] Interval Transfer Bandwidth Retr Cwnd [ 4] 0.00-1.00 sec 62.1 MBytes 520 Mbits/sec 0 288 KBytes [ 4] 1.00-2.00 sec 61.0 MBytes 512 Mbits/sec 0 288 KBytes [ 87.782547] random: crng init done [ 4] 2.00-3.00 sec 61.3 MBytes 515 Mbits/sec 0 300 KBytes [ 4] 3.00-4.00 sec 61.1 MBytes 512 Mbits/sec 0 300 KBytes [ 4] 4.00-5.00 sec 61.4 MBytes 515 Mbits/sec 0 300 KBytes [ 4] 5.00-6.00 sec 61.1 MBytes 513 Mbits/sec 0 300 KBytes [ 4] 6.00-7.00 sec 61.1 MBytes 513 Mbits/sec 0 300 KBytes [ 4] 7.00-8.00 sec 61.6 MBytes 517 Mbits/sec 0 300 KBytes [ 4] 8.00-9.00 sec 61.3 MBytes 515 Mbits/sec 0 300 KBytes [ 4] 9.00-10.00 sec 61.6 MBytes 517 Mbits/sec 0 300 KBytes - - - - - - - - - - - - - - - - - - - - - - - - - [ ID] Interval Transfer Bandwidth Retr [ 4] 0.00-10.00 sec 614 MBytes 515 Mbits/sec 0 sender [ 4] 0.00-10.00 sec 613 MBytes 514 Mbits/sec receiver Note that the results above are with TSO off. With TSO on, I get 921 Mbps. However, the patch should not affect the case where TSO is on. Regards, Niklas
