diff options
| author | Yafang Shao <laoar.shao@gmail.com> | 2018-11-11 15:10:10 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2018-11-11 21:24:18 +0300 |
| commit | 5e13a0d3f5c11df7eb297e6583cf874a79a00374 (patch) | |
| tree | 6836047a30acd0c55c00e11d2814b427fadca5a5 /net/ipv4/tcp_input.c | |
| parent | 0cf3a68a53829815db58461da1807728437c5de2 (diff) | |
| download | linux-5e13a0d3f5c11df7eb297e6583cf874a79a00374.tar.xz | |
tcp: minor optimization in tcp ack fast path processing
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>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4/tcp_input.c')
| -rw-r--r-- | net/ipv4/tcp_input.c | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 2868ef28ce52..edaaebfbcd46 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. |