>> > @@ -720,6 +720,7 @@ void __sock_recv_timestamp(struct msghdr *msg, struct
>> > sock *sk,
>> > empty = 0;
>> > if (shhwtstamps &&
>> > (sk->sk_tsflags & SOF_TIMESTAMPING_RAW_HARDWARE) &&
>> > + (empty || !skb_is_err_queue(skb)) &&
>> > ktime_to_timespec_cond(shhwtstamps->hwtstamp, tss.ts + 2)) {
>>
>> I find skb->tstamp == 0 easier to understand than the condition on empty.
>>
>> Indeed, this is so non-obvious that I would suggest another helper function
>> skb_is_hwtx_tstamp with a concise comment about the race condition
>> between tx software and hardware timestamps (as in the last sentence of
>> the commit message).
>
> Should it include also the skb_is_err_queue() check? If it returned
> true for both TX and RX HW timestamps, maybe it could be called
> skb_has_hw_tstamp?
For the purpose of documenting why this complex condition exists,
I would call the skb_is_err_queue in that helper function and make
it tx + hw specific.
