Re: [PATCH net] ixgbe: check return value of napi_complete_done()

On 9/21/18 7:59 AM, Eric Dumazet wrote:

On 09/21/2018 07:55 AM, Alexei Starovoitov wrote:

quoted

should we remove ndo_poll_controller then?
My understanding that the patch helps by not letting
drivers do napi_schedule() for all queues into this_cpu, right?
But most of the drivers do exactly that in their ndo_poll_controller
implementations. Means most of the drivers will experience
this nasty behavior.

Some legacy drivers do not use NAPI yet, but provide ndo_poll_controller()

I believe users caring about system behavior with multi queue NIC are
all using NAPI enabled drivers, so this should be fine.

I'm not following.
All modern napi enabled drivers need to _remove_ ndo_poll_controller
from the driver. This is a lot of churn.
Isn't it cleaner (less error prone) to introduce new ndo
for legacy drivers without napi?