ice: Support 5 layer topology
There is a performance issue when the number of VSIs are not multiple of 8. This is caused due to the max children limitation per node(8) in 9 layer topology. The BW credits are shared evenly among the children by default. Assume one node has 8 children and the other has 1. The parent of these nodes share the BW credit equally among them. Apparently this causes a problem for the first node which has 8 children. The 9th VM get more BW credits than the first 8 VMs. Example: 1) With 8 VM's: for x in 0 1 2 3 4 5 6 7; do taskset -c ${x} netperf -P0 -H 172.68.169.125 & sleep .1 ; done tx_queue_0_packets: 23283027 tx_queue_1_packets: 23292289 tx_queue_2_packets: 23276136 tx_queue_3_packets: 23279828 tx_queue_4_packets: 23279828 tx_queue_5_packets: 23279333 tx_queue_6_packets: 23277745 tx_queue_7_packets: 23279950 tx_queue_8_packets: 0 2) With 9 VM's: for x in 0 1 2 3 4 5 6 7 8; do taskset -c ${x} netperf -P0 -H 172.68.169.125 & sleep .1 ; done tx_queue_0_packets: 24163396 tx_queue_1_packets: 24164623 tx_queue_2_packets: 24163188 tx_queue_3_packets: 24163701 tx_queue_4_packets: 24163683 tx_queue_5_packets: 24164668 tx_queue_6_packets: 23327200 tx_queue_7_packets: 24163853 tx_queue_8_packets: 91101417 So on average queue 8 statistics show that 3.7 times more packets were send there than to the other queues. The FW starting with version 3.20, has increased the max number of children per node by reducing the number of layers from 9 to 5. Reflect this on driver side. Signed-off-by: Raj Victor <victor.raj@intel.com> Co-developed-by: Michal Wilczynski <michal.wilczynski@intel.com> Signed-off-by: Michal Wilczynski <michal.wilczynski@intel.com> Co-developed-by: Mateusz Polchlopek <mateusz.polchlopek@intel.com> Signed-off-by: Mateusz Polchlopek <mateusz.polchlopek@intel.com> Tested-by: Pucha Himasekhar Reddy <himasekharx.reddy.pucha@intel.com> Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
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