On 7/15/25 5:14 PM, Chia-Yu Chang (Nokia) wrote: >> On 7/4/25 10:53 AM, [email protected] wrote: >>> @@ -285,9 +297,33 @@ static inline void >>> tcp_ecn_received_counters(struct sock *sk, >>> >>> if (len > 0) { >>> u8 minlen = >>> tcp_ecnfield_to_accecn_optfield(ecnfield); >>> + u32 oldbytes = tp->received_ecn_bytes[ecnfield - >>> + 1]; >>> + >>> tp->received_ecn_bytes[ecnfield - 1] += len; >>> tp->accecn_minlen = max_t(u8, tp->accecn_minlen, >>> minlen); >>> + >>> + /* Demand AccECN option at least every 2^22 bytes to >>> + * avoid overflowing the ECN byte counters. >>> + */ >>> + if ((tp->received_ecn_bytes[ecnfield - 1] ^ oldbytes) >>> & >>> + ~((1 << 22) - 1)) { >> >> I don't understand the above statement, I don't think it yield the result >> expected according to the above comment. > > Hi Paolo, > > I was thinking to change it into GENMASK_U32() and comments like below. > > It is intended to send AccECN option at least once per 2^22-byte increase in > the counter.
Ok, I see it now. Please mention explicitly the above in the comment and test just the 22 bit. /P
