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Diffstat (limited to 'net/ipv4/tcp_output.c')
-rw-r--r--net/ipv4/tcp_output.c49
1 files changed, 33 insertions, 16 deletions
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index a369e8a70b2c..534e5fdb04c1 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -350,6 +350,15 @@ static void tcp_ecn_send_syn(struct sock *sk, struct sk_buff *skb)
}
}
+static void tcp_ecn_clear_syn(struct sock *sk, struct sk_buff *skb)
+{
+ if (sock_net(sk)->ipv4.sysctl_tcp_ecn_fallback)
+ /* tp->ecn_flags are cleared at a later point in time when
+ * SYN ACK is ultimatively being received.
+ */
+ TCP_SKB_CB(skb)->tcp_flags &= ~(TCPHDR_ECE | TCPHDR_CWR);
+}
+
static void
tcp_ecn_make_synack(const struct request_sock *req, struct tcphdr *th,
struct sock *sk)
@@ -1018,6 +1027,7 @@ static int tcp_transmit_skb(struct sock *sk, struct sk_buff *skb, int clone_it,
TCP_ADD_STATS(sock_net(sk), TCP_MIB_OUTSEGS,
tcp_skb_pcount(skb));
+ tp->segs_out += tcp_skb_pcount(skb);
/* OK, its time to fill skb_shinfo(skb)->gso_segs */
skb_shinfo(skb)->gso_segs = tcp_skb_pcount(skb);
@@ -1163,7 +1173,7 @@ int tcp_fragment(struct sock *sk, struct sk_buff *skb, u32 len,
return -ENOMEM;
/* Get a new skb... force flag on. */
- buff = sk_stream_alloc_skb(sk, nsize, gfp);
+ buff = sk_stream_alloc_skb(sk, nsize, gfp, true);
if (!buff)
return -ENOMEM; /* We'll just try again later. */
@@ -1722,7 +1732,7 @@ static int tso_fragment(struct sock *sk, struct sk_buff *skb, unsigned int len,
if (skb->len != skb->data_len)
return tcp_fragment(sk, skb, len, mss_now, gfp);
- buff = sk_stream_alloc_skb(sk, 0, gfp);
+ buff = sk_stream_alloc_skb(sk, 0, gfp, true);
if (unlikely(!buff))
return -ENOMEM;
@@ -1941,7 +1951,7 @@ static int tcp_mtu_probe(struct sock *sk)
}
/* We're allowed to probe. Build it now. */
- nskb = sk_stream_alloc_skb(sk, probe_size, GFP_ATOMIC);
+ nskb = sk_stream_alloc_skb(sk, probe_size, GFP_ATOMIC, false);
if (!nskb)
return -1;
sk->sk_wmem_queued += nskb->truesize;
@@ -2392,7 +2402,7 @@ u32 __tcp_select_window(struct sock *sk)
if (free_space < (full_space >> 1)) {
icsk->icsk_ack.quick = 0;
- if (sk_under_memory_pressure(sk))
+ if (tcp_under_memory_pressure(sk))
tp->rcv_ssthresh = min(tp->rcv_ssthresh,
4U * tp->advmss);
@@ -2615,6 +2625,10 @@ int __tcp_retransmit_skb(struct sock *sk, struct sk_buff *skb)
}
}
+ /* RFC3168, section 6.1.1.1. ECN fallback */
+ if ((TCP_SKB_CB(skb)->tcp_flags & TCPHDR_SYN_ECN) == TCPHDR_SYN_ECN)
+ tcp_ecn_clear_syn(sk, skb);
+
tcp_retrans_try_collapse(sk, skb, cur_mss);
/* Make a copy, if the first transmission SKB clone we made
@@ -2816,8 +2830,10 @@ begin_fwd:
* connection tear down and (memory) recovery.
* Otherwise tcp_send_fin() could be tempted to either delay FIN
* or even be forced to close flow without any FIN.
+ * In general, we want to allow one skb per socket to avoid hangs
+ * with edge trigger epoll()
*/
-static void sk_forced_wmem_schedule(struct sock *sk, int size)
+void sk_forced_mem_schedule(struct sock *sk, int size)
{
int amt, status;
@@ -2841,7 +2857,7 @@ void tcp_send_fin(struct sock *sk)
* Note: in the latter case, FIN packet will be sent after a timeout,
* as TCP stack thinks it has already been transmitted.
*/
- if (tskb && (tcp_send_head(sk) || sk_under_memory_pressure(sk))) {
+ if (tskb && (tcp_send_head(sk) || tcp_under_memory_pressure(sk))) {
coalesce:
TCP_SKB_CB(tskb)->tcp_flags |= TCPHDR_FIN;
TCP_SKB_CB(tskb)->end_seq++;
@@ -2864,7 +2880,7 @@ coalesce:
return;
}
skb_reserve(skb, MAX_TCP_HEADER);
- sk_forced_wmem_schedule(sk, skb->truesize);
+ sk_forced_mem_schedule(sk, skb->truesize);
/* FIN eats a sequence byte, write_seq advanced by tcp_queue_skb(). */
tcp_init_nondata_skb(skb, tp->write_seq,
TCPHDR_ACK | TCPHDR_FIN);
@@ -3175,7 +3191,7 @@ static int tcp_send_syn_data(struct sock *sk, struct sk_buff *syn)
/* limit to order-0 allocations */
space = min_t(size_t, space, SKB_MAX_HEAD(MAX_TCP_HEADER));
- syn_data = sk_stream_alloc_skb(sk, space, sk->sk_allocation);
+ syn_data = sk_stream_alloc_skb(sk, space, sk->sk_allocation, false);
if (!syn_data)
goto fallback;
syn_data->ip_summed = CHECKSUM_PARTIAL;
@@ -3241,7 +3257,7 @@ int tcp_connect(struct sock *sk)
return 0;
}
- buff = sk_stream_alloc_skb(sk, 0, sk->sk_allocation);
+ buff = sk_stream_alloc_skb(sk, 0, sk->sk_allocation, true);
if (unlikely(!buff))
return -ENOBUFS;
@@ -3382,7 +3398,7 @@ EXPORT_SYMBOL_GPL(tcp_send_ack);
* one is with SEG.SEQ=SND.UNA to deliver urgent pointer, another is
* out-of-date with SND.UNA-1 to probe window.
*/
-static int tcp_xmit_probe_skb(struct sock *sk, int urgent)
+static int tcp_xmit_probe_skb(struct sock *sk, int urgent, int mib)
{
struct tcp_sock *tp = tcp_sk(sk);
struct sk_buff *skb;
@@ -3400,6 +3416,7 @@ static int tcp_xmit_probe_skb(struct sock *sk, int urgent)
*/
tcp_init_nondata_skb(skb, tp->snd_una - !urgent, TCPHDR_ACK);
skb_mstamp_get(&skb->skb_mstamp);
+ NET_INC_STATS_BH(sock_net(sk), mib);
return tcp_transmit_skb(sk, skb, 0, GFP_ATOMIC);
}
@@ -3407,12 +3424,12 @@ 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_xmit_probe_skb(sk, 0);
+ tcp_xmit_probe_skb(sk, 0, LINUX_MIB_TCPWINPROBE);
}
}
/* Initiate keepalive or window probe from timer. */
-int tcp_write_wakeup(struct sock *sk)
+int tcp_write_wakeup(struct sock *sk, int mib)
{
struct tcp_sock *tp = tcp_sk(sk);
struct sk_buff *skb;
@@ -3449,8 +3466,8 @@ int tcp_write_wakeup(struct sock *sk)
return err;
} else {
if (between(tp->snd_up, tp->snd_una + 1, tp->snd_una + 0xFFFF))
- tcp_xmit_probe_skb(sk, 1);
- return tcp_xmit_probe_skb(sk, 0);
+ tcp_xmit_probe_skb(sk, 1, mib);
+ return tcp_xmit_probe_skb(sk, 0, mib);
}
}
@@ -3464,7 +3481,7 @@ void tcp_send_probe0(struct sock *sk)
unsigned long probe_max;
int err;
- err = tcp_write_wakeup(sk);
+ err = tcp_write_wakeup(sk, LINUX_MIB_TCPWINPROBE);
if (tp->packets_out || !tcp_send_head(sk)) {
/* Cancel probe timer, if it is not required. */
@@ -3490,7 +3507,7 @@ void tcp_send_probe0(struct sock *sk)
probe_max = TCP_RESOURCE_PROBE_INTERVAL;
}
inet_csk_reset_xmit_timer(sk, ICSK_TIME_PROBE0,
- inet_csk_rto_backoff(icsk, probe_max),
+ tcp_probe0_when(sk, probe_max),
TCP_RTO_MAX);
}
generated by cgit v1.2.3-70-g09d2 (git 2.48.1) at 2025-03-28 03:43:57 +0000