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Diffstat (limited to 'net/ipv4/tcp_input.c')
-rw-r--r--net/ipv4/tcp_input.c89
1 files changed, 50 insertions, 39 deletions
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 29c6fc8c7716..83330a6cb242 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -437,7 +437,7 @@ static void tcp_grow_window(struct sock *sk, const struct sk_buff *skb)
/* 3. Try to fixup all. It is made immediately after connection enters
* established state.
*/
-void tcp_init_buffer_space(struct sock *sk)
+static void tcp_init_buffer_space(struct sock *sk)
{
int tcp_app_win = sock_net(sk)->ipv4.sysctl_tcp_app_win;
struct tcp_sock *tp = tcp_sk(sk);
@@ -2183,8 +2183,7 @@ static bool tcp_time_to_recover(struct sock *sk, int flag)
}
/* Detect loss in event "A" above by marking head of queue up as lost.
- * For non-SACK(Reno) senders, the first "packets" number of segments
- * are considered lost. For RFC3517 SACK, a segment is considered lost if it
+ * For RFC3517 SACK, a segment is considered lost if it
* has at least tp->reordering SACKed seqments above it; "packets" refers to
* the maximum SACKed segments to pass before reaching this limit.
*/
@@ -2192,10 +2191,9 @@ static void tcp_mark_head_lost(struct sock *sk, int packets, int mark_head)
{
struct tcp_sock *tp = tcp_sk(sk);
struct sk_buff *skb;
- int cnt, oldcnt, lost;
- unsigned int mss;
+ int cnt;
/* Use SACK to deduce losses of new sequences sent during recovery */
- const u32 loss_high = tcp_is_sack(tp) ? tp->snd_nxt : tp->high_seq;
+ const u32 loss_high = tp->snd_nxt;
WARN_ON(packets > tp->packets_out);
skb = tp->lost_skb_hint;
@@ -2218,26 +2216,11 @@ static void tcp_mark_head_lost(struct sock *sk, int packets, int mark_head)
if (after(TCP_SKB_CB(skb)->end_seq, loss_high))
break;
- oldcnt = cnt;
- if (tcp_is_reno(tp) ||
- (TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_ACKED))
+ if (TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_ACKED)
cnt += tcp_skb_pcount(skb);
- if (cnt > packets) {
- if (tcp_is_sack(tp) ||
- (TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_ACKED) ||
- (oldcnt >= packets))
- break;
-
- mss = tcp_skb_mss(skb);
- /* If needed, chop off the prefix to mark as lost. */
- lost = (packets - oldcnt) * mss;
- if (lost < skb->len &&
- tcp_fragment(sk, TCP_FRAG_IN_RTX_QUEUE, skb,
- lost, mss, GFP_ATOMIC) < 0)
- break;
- cnt = packets;
- }
+ if (cnt > packets)
+ break;
tcp_skb_mark_lost(tp, skb);
@@ -2849,8 +2832,7 @@ static void tcp_fastretrans_alert(struct sock *sk, const u32 prior_snd_una,
if (tcp_try_undo_partial(sk, prior_snd_una))
return;
/* Partial ACK arrived. Force fast retransmit. */
- do_lost = tcp_is_reno(tp) ||
- tcp_force_fast_retransmit(sk);
+ do_lost = tcp_force_fast_retransmit(sk);
}
if (tcp_try_undo_dsack(sk)) {
tcp_try_keep_open(sk);
@@ -3014,7 +2996,7 @@ void tcp_rearm_rto(struct sock *sk)
rto = usecs_to_jiffies(max_t(int, delta_us, 1));
}
tcp_reset_xmit_timer(sk, ICSK_TIME_RETRANS, rto,
- TCP_RTO_MAX, tcp_rtx_queue_head(sk));
+ TCP_RTO_MAX);
}
}
@@ -3291,7 +3273,7 @@ static void tcp_ack_probe(struct sock *sk)
unsigned long when = tcp_probe0_when(sk, TCP_RTO_MAX);
tcp_reset_xmit_timer(sk, ICSK_TIME_PROBE0,
- when, TCP_RTO_MAX, NULL);
+ when, TCP_RTO_MAX);
}
}
@@ -4323,6 +4305,33 @@ static void tcp_sack_maybe_coalesce(struct tcp_sock *tp)
}
}
+static void tcp_sack_compress_send_ack(struct sock *sk)
+{
+ struct tcp_sock *tp = tcp_sk(sk);
+
+ if (!tp->compressed_ack)
+ return;
+
+ if (hrtimer_try_to_cancel(&tp->compressed_ack_timer) == 1)
+ __sock_put(sk);
+
+ /* Since we have to send one ack finally,
+ * substract one from tp->compressed_ack to keep
+ * LINUX_MIB_TCPACKCOMPRESSED accurate.
+ */
+ NET_ADD_STATS(sock_net(sk), LINUX_MIB_TCPACKCOMPRESSED,
+ tp->compressed_ack - 1);
+
+ tp->compressed_ack = 0;
+ tcp_send_ack(sk);
+}
+
+/* Reasonable amount of sack blocks included in TCP SACK option
+ * The max is 4, but this becomes 3 if TCP timestamps are there.
+ * Given that SACK packets might be lost, be conservative and use 2.
+ */
+#define TCP_SACK_BLOCKS_EXPECTED 2
+
static void tcp_sack_new_ofo_skb(struct sock *sk, u32 seq, u32 end_seq)
{
struct tcp_sock *tp = tcp_sk(sk);
@@ -4335,6 +4344,8 @@ static void tcp_sack_new_ofo_skb(struct sock *sk, u32 seq, u32 end_seq)
for (this_sack = 0; this_sack < cur_sacks; this_sack++, sp++) {
if (tcp_sack_extend(sp, seq, end_seq)) {
+ if (this_sack >= TCP_SACK_BLOCKS_EXPECTED)
+ tcp_sack_compress_send_ack(sk);
/* Rotate this_sack to the first one. */
for (; this_sack > 0; this_sack--, sp--)
swap(*sp, *(sp - 1));
@@ -4344,6 +4355,9 @@ static void tcp_sack_new_ofo_skb(struct sock *sk, u32 seq, u32 end_seq)
}
}
+ if (this_sack >= TCP_SACK_BLOCKS_EXPECTED)
+ tcp_sack_compress_send_ack(sk);
+
/* Could not find an adjacent existing SACK, build a new one,
* put it at the front, and shift everyone else down. We
* always know there is at least one SACK present already here.
@@ -4351,8 +4365,6 @@ static void tcp_sack_new_ofo_skb(struct sock *sk, u32 seq, u32 end_seq)
* If the sack array is full, forget about the last one.
*/
if (this_sack >= TCP_NUM_SACKS) {
- if (tp->compressed_ack > TCP_FASTRETRANS_THRESH)
- tcp_send_ack(sk);
this_sack--;
tp->rx_opt.num_sacks--;
sp--;
@@ -5272,15 +5284,13 @@ send_now:
if (tp->compressed_ack_rcv_nxt != tp->rcv_nxt) {
tp->compressed_ack_rcv_nxt = tp->rcv_nxt;
- if (tp->compressed_ack > TCP_FASTRETRANS_THRESH)
- NET_ADD_STATS(sock_net(sk), LINUX_MIB_TCPACKCOMPRESSED,
- tp->compressed_ack - TCP_FASTRETRANS_THRESH);
- tp->compressed_ack = 0;
+ tp->dup_ack_counter = 0;
}
-
- if (++tp->compressed_ack <= TCP_FASTRETRANS_THRESH)
+ if (tp->dup_ack_counter < TCP_FASTRETRANS_THRESH) {
+ tp->dup_ack_counter++;
goto send_now;
-
+ }
+ tp->compressed_ack++;
if (hrtimer_is_queued(&tp->compressed_ack_timer))
return;
@@ -5293,8 +5303,9 @@ send_now:
delay = min_t(unsigned long, sock_net(sk)->ipv4.sysctl_tcp_comp_sack_delay_ns,
rtt * (NSEC_PER_USEC >> 3)/20);
sock_hold(sk);
- hrtimer_start(&tp->compressed_ack_timer, ns_to_ktime(delay),
- HRTIMER_MODE_REL_PINNED_SOFT);
+ hrtimer_start_range_ns(&tp->compressed_ack_timer, ns_to_ktime(delay),
+ sock_net(sk)->ipv4.sysctl_tcp_comp_sack_slack_ns,
+ HRTIMER_MODE_REL_PINNED_SOFT);
}
static inline void tcp_ack_snd_check(struct sock *sk)
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-25 00:41:45 +0100