[RFC] ath10k: change to do napi_enable and napi_disable when insmod and rmmod for sdio

[Wen Gong]

On 2020-08-20 18:52, Krishna Chaitanya wrote:
> On Thu, Aug 20, 2020 at 3:45 PM Wen Gong <wgong at codeaurora.org> wrote:
>> 
>> On 2020-08-20 17:19, Krishna Chaitanya wrote:
...
>> >> I'm not really convinced that this is the right fix, but I'm no NAPI
>> >> expert. Can anyone else help?
>> > Calling napi_disable() twice can lead to hangs, but moving NAPI from
>> > start/stop to
>> > the probe isn't the right approach as the datapath is tied to
>> > start/stop.
>> >
>> > Maybe check the state of NAPI before disable?
>> >
>> >  if (test_bit(NAPI_STATE_SCHED, &ar->napi.napi.state))
>> >   napi_disable(&ar->napi)
>> > or maintain napi_state like this
>> > https://patchwork.kernel.org/patch/10249365/
>> it is better to use above link's patch.
>> napi.state is controlled by napi API, it is better ath10k not know it.
> Sure, but IMHO just canceling the async rx work should solve the issue.
Oh no, canceling the async rx work will not solve this issue, rx worker
ath10k_rx_indication_async_work call napi_schedule, after napi_complete,
the NAPI_STATE_SCHED will clear.
The issue of this patch is because 2 thread called to hif_stop and
NAPI_STATE_SCHED not clear.
...