| Message ID | 1541938210-11797-1-git-send-email-laoar.shao@gmail.com |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
| Series | [net-next,v2] tcp: minor optimization in tcp ack fast path processing | expand |
On 11/11/2018 04:10 AM, Yafang Shao wrote: > Bitwise operation is a little faster. > So I replace after() with using the flag FLAG_SND_UNA_ADVANCED as it is > already set before. > > In addtion, there's another similar improvement in tcp_cwnd_reduction(). > > Cc: Joe Perches <joe@perches.com> > Suggested-by: Eric Dumazet <edumazet@google.com> > Signed-off-by: Yafang Shao <laoar.shao@gmail.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Thanks.
From: Yafang Shao <laoar.shao@gmail.com> Date: Sun, 11 Nov 2018 20:10:10 +0800 > Bitwise operation is a little faster. > So I replace after() with using the flag FLAG_SND_UNA_ADVANCED as it is > already set before. > > In addtion, there's another similar improvement in tcp_cwnd_reduction(). > > Cc: Joe Perches <joe@perches.com> > Suggested-by: Eric Dumazet <edumazet@google.com> > Signed-off-by: Yafang Shao <laoar.shao@gmail.com> Applied.
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 2868ef2..edaaebf 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -2457,8 +2457,8 @@ void tcp_cwnd_reduction(struct sock *sk, int newly_acked_sacked, int flag) u64 dividend = (u64)tp->snd_ssthresh * tp->prr_delivered + tp->prior_cwnd - 1; sndcnt = div_u64(dividend, tp->prior_cwnd) - tp->prr_out; - } else if ((flag & FLAG_RETRANS_DATA_ACKED) && - !(flag & FLAG_LOST_RETRANS)) { + } else if ((flag & (FLAG_RETRANS_DATA_ACKED | FLAG_LOST_RETRANS)) == + FLAG_RETRANS_DATA_ACKED) { sndcnt = min_t(int, delta, max_t(int, tp->prr_delivered - tp->prr_out, newly_acked_sacked) + 1); @@ -3610,7 +3610,8 @@ static int tcp_ack(struct sock *sk, const struct sk_buff *skb, int flag) if (flag & FLAG_UPDATE_TS_RECENT) tcp_replace_ts_recent(tp, TCP_SKB_CB(skb)->seq); - if (!(flag & FLAG_SLOWPATH) && after(ack, prior_snd_una)) { + if ((flag & (FLAG_SLOWPATH | FLAG_SND_UNA_ADVANCED)) == + FLAG_SND_UNA_ADVANCED) { /* Window is constant, pure forward advance. * No more checks are required. * Note, we use the fact that SND.UNA>=SND.WL2.
Bitwise operation is a little faster. So I replace after() with using the flag FLAG_SND_UNA_ADVANCED as it is already set before. In addtion, there's another similar improvement in tcp_cwnd_reduction(). Cc: Joe Perches <joe@perches.com> Suggested-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Yafang Shao <laoar.shao@gmail.com> --- net/ipv4/tcp_input.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-)