igb: Fix the transmission mode of queue 0 for Qav mode
When Qav mode is enabled, queue 0 should be kept on Stream Reservation
mode. From the i210 datasheet, section 8.12.19:
"Note: Queue0 QueueMode must be set to 1b when TransmitMode is set to
Qav." ("QueueMode 1b" represents the Stream Reservation mode)
The solution is to give queue 0 the all the credits it might need, so
it has priority over queue 1.
A situation where this can happen is when cbs is "installed" only on
queue 1, leaving queue 0 alone. For example:
$ tc qdisc replace dev enp2s0 handle 100: parent root mqprio num_tc 3 \
map 2 2 1 0 2 2 2 2 2 2 2 2 2 2 2 2 queues 1@0 1@1 2@2 hw 0
$ tc qdisc replace dev enp2s0 parent 100:2 cbs locredit -1470 \
hicredit 30 sendslope -980000 idleslope 20000 offload 1
Signed-off-by: Vinicius Costa Gomes <[email protected]>
Tested-by: Aaron Brown <[email protected]>
Signed-off-by: Jeff Kirsher <[email protected]>
1 file changed
