Search Linux Wireless

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

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 8/20/20 9:08 AM, Krishna Chaitanya wrote:
On Thu, Aug 20, 2020 at 8:07 PM Wen Gong <wgong@xxxxxxxxxxxxxx> wrote:

On 2020-08-20 18:52, Krishna Chaitanya wrote:
On Thu, Aug 20, 2020 at 3:45 PM Wen Gong <wgong@xxxxxxxxxxxxxx> 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.
That fix is still valid and good to have.

ndev_stop being called twice is typical scenarios (stop vs rmmod), so
  just checking the netdev_flags for IFF_UP and returning from hif_Stop
should suffice, no?

My approach to fix this problem was to add a boolean in ath10k as to whether
it had napi enabled or not, and then check that before trying to enable/disable
it again.  Seems to work fine, and cleaner in my mind than checking internal
napi flags.

Thanks,
Ben


--
Ben Greear <greearb@xxxxxxxxxxxxxxx>
Candela Technologies Inc  http://www.candelatech.com



[Index of Archives]     [Linux Host AP]     [ATH6KL]     [Linux Wireless Personal Area Network]     [Linux Bluetooth]     [Wireless Regulations]     [Linux Netdev]     [Kernel Newbies]     [Linux Kernel]     [IDE]     [Git]     [Netfilter]     [Bugtraq]     [Yosemite Hiking]     [MIPS Linux]     [ARM Linux]     [Linux RAID]

  Powered by Linux