On Mon, Jan 25, 2021 at 7:44 PM Ferruh Yigit [off-list ref] wrote:

quoted

quoted

+       if (rx_offloads != port->dev_conf.rxmode.offloads) {
+               uint16_t qid;
+
+               port->dev_conf.rxmode.offloads = rx_offloads;
+
+               /* Apply JUMBO_FRAME offload configuration to Rx queue(s) */
+               for (qid = 0; qid < port->dev_info.nb_rx_queues; qid++) {
+                       if (on)
+                               port->rx_conf[qid].offloads |= DEV_RX_OFFLOAD_JUMBO_FRAME;
+                       else
+                               port->rx_conf[qid].offloads &= ~DEV_RX_OFFLOAD_JUMBO_FRAME;
+               }

Is it correct to set per-queue offloads that aren't advertised by the PMD
as supported in rx_queue_offload_capa?

'port->rx_conf[]' is testpmd struct, and 'port->dev_conf.rxmode.offloads' values
are reflected to 'port->rx_conf[].offloads' for all queues.

We should set the offload in 'port->rx_conf[].offloads' if it is set in
'port->dev_conf.rxmode.offloads'.

If a port has capability for 'JUMBO_FRAME', 'port->rx_conf[].offloads' can have
it. And the port level capability is already checked above.

I'm still not 100% clear about the per-queue offload question.

With this patch, and jumbo max packet size configured (on the command
line in this case), I see:

testpmd> show port 0 rx_offload configuration
Rx Offloading Configuration of port 0 :
  Port : JUMBO_FRAME
  Queue[ 0] : JUMBO_FRAME

testpmd> show port 0 rx_offload capabilities
Rx Offloading Capabilities of port 0 :
  Per Queue :
  Per Port  : VLAN_STRIP IPV4_CKSUM UDP_CKSUM TCP_CKSUM TCP_LRO
OUTER_IPV4_CKSUM VLAN_FILTER VLAN_EXTEND JUMBO_FRAME SCATTER TIMESTAMP
KEEP_CRC OUTER_UDP_CKSUM RSS_HASH

Yet if I configure a jumbo MTU starting with standard max packet size,
jumbo is only enabled at the port level:
testpmd> port config mtu 0 9000
testpmd> port start all

testpmd> show port 0 rx_offload configuration
Rx Offloading Configuration of port 0 :
  Port : JUMBO_FRAME
  Queue[ 0] :

It still seems odd for a per-queue offload to be enabled on a PMD that
doesn't support per-queue receive offloads.