Rajkumar Manoharan <rmanohar@xxxxxxxxxxxxxx> writes:
>>> diff --git a/net/mac80211/sta_info.h b/net/mac80211/sta_info.h
>>> index b1b0fd6a2e21..ddc2c882c91c 100644
>>> --- a/net/mac80211/sta_info.h
>>> +++ b/net/mac80211/sta_info.h
>>> @@ -135,6 +135,7 @@ struct airtime_info {
>>> u64 rx_airtime;
>>> u64 tx_airtime;
>>> s64 deficit;
>>> + s32 budget;
>>
>> Why signed? This should never become negative unless something is wrong
>> with the accounting somewhere?
>>
>> Related, are we sure there are no "leaks", i.e., packets that increase
>> the budget on dequeue, but are never tx_completed?
>
> Just to avoid wraparound issue. Yeah... Irrespective of signedness if
> there is mismatch in tx and tx-compl, it may stall tx. no? I was
> worrying what if the driver is freeing skb silently instead of
> free_txskb().
>
> Will change it to unsigned and add WARN_ON statement upon adjustment.
> is it OK?
Just note that WARN_ON() is pretty dangerous, especially on data path,
as it can kill the host with excessive spamming. WARN_ON_ONCE() or a
ratelimited printk() variant are much safer choises.
--
Kalle Valo
