tcp_bbr: remove bbr->tso_segs_goal

Its value is computed then immediately used,
there is no need to store it.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/ipv4/tcp_bbr.c b/net/ipv4/tcp_bbr.c
index afc0567..c92014c 100644 (file)
--- a/net/ipv4/tcp_bbr.c
+++ b/net/ipv4/tcp_bbr.c
@@ -97,10 +97,9 @@ struct bbr {
                packet_conservation:1,  /* use packet conservation? */
                restore_cwnd:1,      /* decided to revert cwnd to old value */
                round_start:1,       /* start of packet-timed tx->ack round? */
-               tso_segs_goal:7,     /* segments we want in each skb we send */
                idle_restart:1,      /* restarting after idle? */
                probe_rtt_round_done:1,  /* a BBR_PROBE_RTT round at 4 pkts? */
-               unused:5,
+               unused:12,
                lt_is_sampling:1,    /* taking long-term ("LT") samples now? */
                lt_rtt_cnt:7,        /* round trips in long-term interval */
                lt_use_bw:1;         /* use lt_bw as our bw estimate? */
@@ -267,10 +266,9 @@ static u32 bbr_min_tso_segs(struct sock *sk)
        return sk->sk_pacing_rate < (bbr_min_tso_rate >> 3) ? 1 : 2;
 }
 
-static void bbr_set_tso_segs_goal(struct sock *sk)
+static u32 bbr_tso_segs_goal(struct sock *sk)
 {
        struct tcp_sock *tp = tcp_sk(sk);
-       struct bbr *bbr = inet_csk_ca(sk);
        u32 segs, bytes;
 
        /* Sort of tcp_tso_autosize() but ignoring
@@ -280,7 +278,7 @@ static void bbr_set_tso_segs_goal(struct sock *sk)
                      GSO_MAX_SIZE - 1 - MAX_TCP_HEADER);
        segs = max_t(u32, bytes / tp->mss_cache, bbr_min_tso_segs(sk));
 
-       bbr->tso_segs_goal = min(segs, 0x7FU);
+       return min(segs, 0x7FU);
 }
 
 /* Save "last known good" cwnd so we can restore it after losses or PROBE_RTT */
@@ -351,7 +349,7 @@ static u32 bbr_target_cwnd(struct sock *sk, u32 bw, int gain)
        cwnd = (((w * gain) >> BBR_SCALE) + BW_UNIT - 1) / BW_UNIT;
 
        /* Allow enough full-sized skbs in flight to utilize end systems. */
-       cwnd += 3 * bbr->tso_segs_goal;
+       cwnd += 3 * bbr_tso_segs_goal(sk);
 
        /* Reduce delayed ACKs by rounding up cwnd to the next even number. */
        cwnd = (cwnd + 1) & ~1U;
@@ -827,7 +825,6 @@ static void bbr_main(struct sock *sk, const struct rate_sample *rs)
 
        bw = bbr_bw(sk);
        bbr_set_pacing_rate(sk, bw, bbr->pacing_gain);
-       bbr_set_tso_segs_goal(sk);
        bbr_set_cwnd(sk, rs, rs->acked_sacked, bw, bbr->cwnd_gain);
 }
 
@@ -837,7 +834,6 @@ static void bbr_init(struct sock *sk)
        struct bbr *bbr = inet_csk_ca(sk);
 
        bbr->prior_cwnd = 0;
-       bbr->tso_segs_goal = 0;  /* default segs per skb until first ACK */
        bbr->rtt_cnt = 0;
        bbr->next_rtt_delivered = 0;
        bbr->prev_ca_state = TCP_CA_Open;