Merge remote-tracking branch 'lsk/v3.10/topic/arm64-hmp' into linux-linaro-lsk

[firefly-linux-kernel-4.4.55.git] / net / ipv4 / tcp_output.c

diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index ec335fabd5cc12daba8addf5de86adc90abbd561..5560abfe6d301b21f137866bc19f1a9d69f7567b 100644 (file)
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -887,8 +887,7 @@ static int tcp_transmit_skb(struct sock *sk, struct sk_buff *skb, int clone_it,
 
        skb_orphan(skb);
        skb->sk = sk;
-       skb->destructor = (sysctl_tcp_limit_output_bytes > 0) ?
-                         tcp_wfree : sock_wfree;
+       skb->destructor = tcp_wfree;
        atomic_add(skb->truesize, &sk->sk_wmem_alloc);
 
        /* Build TCP header and checksum it. */
@@ -977,6 +976,9 @@ static void tcp_queue_skb(struct sock *sk, struct sk_buff *skb)
 static void tcp_set_skb_tso_segs(const struct sock *sk, struct sk_buff *skb,
                                 unsigned int mss_now)
 {
+       /* Make sure we own this skb before messing gso_size/gso_segs */
+       WARN_ON_ONCE(skb_cloned(skb));
+
        if (skb->len <= mss_now || !sk_can_gso(sk) ||
            skb->ip_summed == CHECKSUM_NONE) {
                /* Avoid the costly divide in the normal
@@ -1058,9 +1060,7 @@ int tcp_fragment(struct sock *sk, struct sk_buff *skb, u32 len,
        if (nsize < 0)
                nsize = 0;
 
-       if (skb_cloned(skb) &&
-           skb_is_nonlinear(skb) &&
-           pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
+       if (skb_unclone(skb, GFP_ATOMIC))
                return -ENOMEM;
 
        /* Get a new skb... force flag on. */
@@ -1623,7 +1623,7 @@ static bool tcp_tso_should_defer(struct sock *sk, struct sk_buff *skb)
 
        /* If a full-sized TSO skb can be sent, do it. */
        if (limit >= min_t(unsigned int, sk->sk_gso_max_size,
-                          sk->sk_gso_max_segs * tp->mss_cache))
+                          tp->xmit_size_goal_segs * tp->mss_cache))
                goto send_now;
 
        /* Middle in queue won't get any more data, full sendable already? */
@@ -1832,7 +1832,6 @@ static bool tcp_write_xmit(struct sock *sk, unsigned int mss_now, int nonagle,
        while ((skb = tcp_send_head(sk))) {
                unsigned int limit;
 
-
                tso_segs = tcp_init_tso_segs(sk, skb, mss_now);
                BUG_ON(!tso_segs);
 
@@ -1861,13 +1860,24 @@ static bool tcp_write_xmit(struct sock *sk, unsigned int mss_now, int nonagle,
                                break;
                }
 
-               /* TSQ : sk_wmem_alloc accounts skb truesize,
-                * including skb overhead. But thats OK.
+               /* TCP Small Queues :
+                * Control number of packets in qdisc/devices to two packets / or ~1 ms.
+                * This allows for :
+                *  - better RTT estimation and ACK scheduling
+                *  - faster recovery
+                *  - high rates
+                * Alas, some drivers / subsystems require a fair amount
+                * of queued bytes to ensure line rate.
+                * One example is wifi aggregation (802.11 AMPDU)
                 */
-               if (atomic_read(&sk->sk_wmem_alloc) >= sysctl_tcp_limit_output_bytes) {
+               limit = max_t(unsigned int, sysctl_tcp_limit_output_bytes,
+                             sk->sk_pacing_rate >> 10);
+
+               if (atomic_read(&sk->sk_wmem_alloc) > limit) {
                        set_bit(TSQ_THROTTLED, &tp->tsq_flags);
                        break;
                }
+
                limit = mss_now;
                if (tso_segs > 1 && !tcp_urg_mode(tp))
                        limit = tcp_mss_split_point(sk, skb, mss_now,
@@ -2329,6 +2339,8 @@ int __tcp_retransmit_skb(struct sock *sk, struct sk_buff *skb)
                int oldpcount = tcp_skb_pcount(skb);
 
                if (unlikely(oldpcount > 1)) {
+                       if (skb_unclone(skb, GFP_ATOMIC))
+                               return -ENOMEM;
                        tcp_init_tso_segs(sk, skb, cur_mss);
                        tcp_adjust_pcount(sk, skb, oldpcount - tcp_skb_pcount(skb));
                }
@@ -2664,7 +2676,7 @@ struct sk_buff *tcp_make_synack(struct sock *sk, struct dst_entry *dst,
        int tcp_header_size;
        int mss;
 
-       skb = alloc_skb(MAX_TCP_HEADER + 15, sk_gfp_atomic(sk, GFP_ATOMIC));
+       skb = sock_wmalloc(sk, MAX_TCP_HEADER + 15, 1, GFP_ATOMIC);
        if (unlikely(!skb)) {
                dst_release(dst);
                return NULL;
@@ -2808,6 +2820,8 @@ void tcp_connect_init(struct sock *sk)
 
        if (likely(!tp->repair))
                tp->rcv_nxt = 0;
+       else
+               tp->rcv_tstamp = tcp_time_stamp;
        tp->rcv_wup = tp->rcv_nxt;
        tp->copied_seq = tp->rcv_nxt;
 
@@ -3088,7 +3102,6 @@ void tcp_send_window_probe(struct sock *sk)
 {
        if (sk->sk_state == TCP_ESTABLISHED) {
                tcp_sk(sk)->snd_wl1 = tcp_sk(sk)->rcv_nxt - 1;
-               tcp_sk(sk)->snd_nxt = tcp_sk(sk)->write_seq;
                tcp_xmit_probe_skb(sk, 0);
        }
 }