diff --git a/include/linux/tcp.h b/include/linux/tcp.h
index f566b8567892ef0bb213de0540b37cfc6ac03ca0..3fa0a9669a3a662be81d4b04f7d117b11012257c 100644
--- a/include/linux/tcp.h
+++ b/include/linux/tcp.h
@@ -130,7 +130,7 @@ struct tcp_sock {
/* inet_connection_sock has to be the first member of tcp_sock */
struct inet_connection_sock inet_conn;
u16 tcp_header_len; /* Bytes of tcp header to send */
- u16 xmit_size_goal_segs; /* Goal for segmenting output packets */
+ u16 gso_segs; /* Max number of segs per GSO packet */
/*
* Header prediction flags
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index dc13a3657e8e1b81ba0cb1fcd5386a9d0b106168..427aee33ffc04ad189d9d0ec24ab8004c25961ec 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -835,47 +835,29 @@ static unsigned int tcp_xmit_size_goal(struct sock *sk, u32 mss_now,
int large_allowed)
{
struct tcp_sock *tp = tcp_sk(sk);
- u32 xmit_size_goal, old_size_goal;
-
- xmit_size_goal = mss_now;
-
- if (large_allowed && sk_can_gso(sk)) {
- u32 gso_size, hlen;
-
- /* Maybe we should/could use sk->sk_prot->max_header here ? */
- hlen = inet_csk(sk)->icsk_af_ops->net_header_len +
- inet_csk(sk)->icsk_ext_hdr_len +
- tp->tcp_header_len;
-
- /* Goal is to send at least one packet per ms,
- * not one big TSO packet every 100 ms.
- * This preserves ACK clocking and is consistent
- * with tcp_tso_should_defer() heuristic.
- */
- gso_size = sk->sk_pacing_rate / (2 * MSEC_PER_SEC);
- gso_size = max_t(u32, gso_size,
- sysctl_tcp_min_tso_segs * mss_now);
-
- xmit_size_goal = min_t(u32, gso_size,
- sk->sk_gso_max_size - 1 - hlen);
-
- xmit_size_goal = tcp_bound_to_half_wnd(tp, xmit_size_goal);
-
- /* We try hard to avoid divides here */
- old_size_goal = tp->xmit_size_goal_segs * mss_now;
-
- if (likely(old_size_goal <= xmit_size_goal &&
- old_size_goal + mss_now > xmit_size_goal)) {
- xmit_size_goal = old_size_goal;
- } else {
- tp->xmit_size_goal_segs =
- min_t(u16, xmit_size_goal / mss_now,
- sk->sk_gso_max_segs);
- xmit_size_goal = tp->xmit_size_goal_segs * mss_now;
- }
+ u32 new_size_goal, size_goal, hlen;
+
+ if (!large_allowed || !sk_can_gso(sk))
+ return mss_now;
+
+ /* Maybe we should/could use sk->sk_prot->max_header here ? */
+ hlen = inet_csk(sk)->icsk_af_ops->net_header_len +
+ inet_csk(sk)->icsk_ext_hdr_len +
+ tp->tcp_header_len;
+
+ new_size_goal = sk->sk_gso_max_size - 1 - hlen;
+ new_size_goal = tcp_bound_to_half_wnd(tp, new_size_goal);
+
+ /* We try hard to avoid divides here */
+ size_goal = tp->gso_segs * mss_now;
+ if (unlikely(new_size_goal < size_goal ||
+ new_size_goal >= size_goal + mss_now)) {
+ tp->gso_segs = min_t(u16, new_size_goal / mss_now,
+ sk->sk_gso_max_segs);
+ size_goal = tp->gso_segs * mss_now;
}
- return max(xmit_size_goal, mss_now);
+ return max(size_goal, mss_now);
}
static int tcp_send_mss(struct sock *sk, int *size_goal, int flags)
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index f5bd4bd3f7e669b3fd48a843d55e7313a30a3409..f37ecf53ee8a96827fc08bd203b0ca8857f8fc34 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -1524,6 +1524,27 @@ static bool tcp_nagle_check(bool partial, const struct tcp_sock *tp,
((nonagle & TCP_NAGLE_CORK) ||
(!nonagle && tp->packets_out && tcp_minshall_check(tp)));
}
+
+/* Return how many segs we'd like on a TSO packet,
+ * to send one TSO packet per ms
+ */
+static u32 tcp_tso_autosize(const struct sock *sk, unsigned int mss_now)
+{
+ u32 bytes, segs;
+
+ bytes = min(sk->sk_pacing_rate >> 10,
+ sk->sk_gso_max_size - 1 - MAX_TCP_HEADER);
+
+ /* Goal is to send at least one packet per ms,
+ * not one big TSO packet every 100 ms.
+ * This preserves ACK clocking and is consistent
+ * with tcp_tso_should_defer() heuristic.
+ */
+ segs = max_t(u32, bytes / mss_now, sysctl_tcp_min_tso_segs);
+
+ return min_t(u32, segs, sk->sk_gso_max_segs);
+}
+
/* Returns the portion of skb which can be sent right away */
static unsigned int tcp_mss_split_point(const struct sock *sk,
const struct sk_buff *skb,
@@ -1731,7 +1752,7 @@ static int tso_fragment(struct sock *sk, struct sk_buff *skb, unsigned int len,
* This algorithm is from John Heffner.
*/
static bool tcp_tso_should_defer(struct sock *sk, struct sk_buff *skb,
- bool *is_cwnd_limited)
+ bool *is_cwnd_limited, u32 max_segs)
{
struct tcp_sock *tp = tcp_sk(sk);
const struct inet_connection_sock *icsk = inet_csk(sk);
@@ -1761,8 +1782,7 @@ static bool tcp_tso_should_defer(struct sock *sk, struct sk_buff *skb,
limit = min(send_win, cong_win);
/* If a full-sized TSO skb can be sent, do it. */
- if (limit >= min_t(unsigned int, sk->sk_gso_max_size,
- tp->xmit_size_goal_segs * tp->mss_cache))
+ if (limit >= max_segs * tp->mss_cache)
goto send_now;
/* Middle in queue won't get any more data, full sendable already? */
@@ -1959,6 +1979,7 @@ static bool tcp_write_xmit(struct sock *sk, unsigned int mss_now, int nonagle,
int cwnd_quota;
int result;
bool is_cwnd_limited = false;
+ u32 max_segs;
sent_pkts = 0;
@@ -1972,6 +1993,7 @@ static bool tcp_write_xmit(struct sock *sk, unsigned int mss_now, int nonagle,
}
}
+ max_segs = tcp_tso_autosize(sk, mss_now);
while ((skb = tcp_send_head(sk))) {
unsigned int limit;
@@ -2004,10 +2026,23 @@ static bool tcp_write_xmit(struct sock *sk, unsigned int mss_now, int nonagle,
break;
} else {
if (!push_one &&
- tcp_tso_should_defer(sk, skb, &is_cwnd_limited))
+ tcp_tso_should_defer(sk, skb, &is_cwnd_limited,
+ max_segs))
break;
}
+ limit = mss_now;
+ if (tso_segs > 1 && !tcp_urg_mode(tp))
+ limit = tcp_mss_split_point(sk, skb, mss_now,
+ min_t(unsigned int,
+ cwnd_quota,
+ max_segs),
+ nonagle);
+
+ if (skb->len > limit &&
+ unlikely(tso_fragment(sk, skb, limit, mss_now, gfp)))
+ break;
+
/* TCP Small Queues :
* Control number of packets in qdisc/devices to two packets / or ~1 ms.
* This allows for :
@@ -2018,8 +2053,8 @@ static bool tcp_write_xmit(struct sock *sk, unsigned int mss_now, int nonagle,
* of queued bytes to ensure line rate.
* One example is wifi aggregation (802.11 AMPDU)
*/
- limit = max_t(unsigned int, sysctl_tcp_limit_output_bytes,
- sk->sk_pacing_rate >> 10);
+ limit = max(2 * skb->truesize, sk->sk_pacing_rate >> 10);
+ limit = min_t(u32, limit, sysctl_tcp_limit_output_bytes);
if (atomic_read(&sk->sk_wmem_alloc) > limit) {
set_bit(TSQ_THROTTLED, &tp->tsq_flags);
@@ -2032,18 +2067,6 @@ static bool tcp_write_xmit(struct sock *sk, unsigned int mss_now, int nonagle,
break;
}
- limit = mss_now;
- if (tso_segs > 1 && !tcp_urg_mode(tp))
- limit = tcp_mss_split_point(sk, skb, mss_now,
- min_t(unsigned int,
- cwnd_quota,
- sk->sk_gso_max_segs),
- nonagle);
-
- if (skb->len > limit &&
- unlikely(tso_fragment(sk, skb, limit, mss_now, gfp)))
- break;
-
if (unlikely(tcp_transmit_skb(sk, skb, 1, gfp)))
break;