[dpdk-users] Facing issues with Interrupt mode (IGB,VFIO)

[Prem Chaitanya]

Hi All,

We modified the l3fwd application to run in interrupt+poll mode. The driver
we used was IGB with Intel I350 NIC.
When we ran with 1 lcore and 1 queue, there were no issues. When we tried
to run with 2 lcores and 2 Rx-queues we are not getting interrupts.
In one of the documentation(DPDK-201.pdf), it was mentioned that IGB driver
doesn't support interrupt mode with multiple lcores since it supports only
1 epoll-fd.
Can you please confirm if this is the case?

Then we went ahead and loaded the VFIO driver and tried to run the same
application.
Now we get an interrupt once and after that when we go back to waiting on
epoll, we dont receive any further interrupts.
But when we print the stats for rx-packets we see that there are packets
waiting in the NIC Rx queue.
Same behavior is observed even when we run application with 1 lcore and 1
Rx queue.

We took the output of "/proc/interrupts", and we don't see the interrupt
count increasing there either.
Looks like interrupt is not getting raised eventhough packets arrive.

Would appreciate the help.

-- 
Regards
Prem