summaryrefslogtreecommitdiff
path: root/net/ipv4/tcp_timer.c
diff options
context:
space:
mode:
Diffstat (limited to 'net/ipv4/tcp_timer.c')
-rw-r--r--net/ipv4/tcp_timer.c89
1 files changed, 38 insertions, 51 deletions
diff --git a/net/ipv4/tcp_timer.c b/net/ipv4/tcp_timer.c
index f87dbc78b6bc..f0c86398e6a7 100644
--- a/net/ipv4/tcp_timer.c
+++ b/net/ipv4/tcp_timer.c
@@ -22,28 +22,14 @@
#include <linux/gfp.h>
#include <net/tcp.h>
-static u32 tcp_retransmit_stamp(const struct sock *sk)
-{
- u32 start_ts = tcp_sk(sk)->retrans_stamp;
-
- if (unlikely(!start_ts)) {
- struct sk_buff *head = tcp_rtx_queue_head(sk);
-
- if (!head)
- return 0;
- start_ts = tcp_skb_timestamp(head);
- }
- return start_ts;
-}
-
static u32 tcp_clamp_rto_to_user_timeout(const struct sock *sk)
{
struct inet_connection_sock *icsk = inet_csk(sk);
u32 elapsed, start_ts;
s32 remaining;
- start_ts = tcp_retransmit_stamp(sk);
- if (!icsk->icsk_user_timeout || !start_ts)
+ start_ts = tcp_sk(sk)->retrans_stamp;
+ if (!icsk->icsk_user_timeout)
return icsk->icsk_rto;
elapsed = tcp_time_stamp(tcp_sk(sk)) - start_ts;
remaining = icsk->icsk_user_timeout - elapsed;
@@ -173,7 +159,20 @@ static void tcp_mtu_probing(struct inet_connection_sock *icsk, struct sock *sk)
tcp_sync_mss(sk, icsk->icsk_pmtu_cookie);
}
-
+static unsigned int tcp_model_timeout(struct sock *sk,
+ unsigned int boundary,
+ unsigned int rto_base)
+{
+ unsigned int linear_backoff_thresh, timeout;
+
+ linear_backoff_thresh = ilog2(TCP_RTO_MAX / rto_base);
+ if (boundary <= linear_backoff_thresh)
+ timeout = ((2 << boundary) - 1) * rto_base;
+ else
+ timeout = ((2 << linear_backoff_thresh) - 1) * rto_base +
+ (boundary - linear_backoff_thresh) * TCP_RTO_MAX;
+ return jiffies_to_msecs(timeout);
+}
/**
* retransmits_timed_out() - returns true if this connection has timed out
* @sk: The current socket
@@ -191,26 +190,15 @@ static bool retransmits_timed_out(struct sock *sk,
unsigned int boundary,
unsigned int timeout)
{
- const unsigned int rto_base = TCP_RTO_MIN;
- unsigned int linear_backoff_thresh, start_ts;
+ unsigned int start_ts;
if (!inet_csk(sk)->icsk_retransmits)
return false;
- start_ts = tcp_retransmit_stamp(sk);
- if (!start_ts)
- return false;
-
- if (likely(timeout == 0)) {
- linear_backoff_thresh = ilog2(TCP_RTO_MAX/rto_base);
+ start_ts = tcp_sk(sk)->retrans_stamp;
+ if (likely(timeout == 0))
+ timeout = tcp_model_timeout(sk, boundary, TCP_RTO_MIN);
- if (boundary <= linear_backoff_thresh)
- timeout = ((2 << boundary) - 1) * rto_base;
- else
- timeout = ((2 << linear_backoff_thresh) - 1) * rto_base +
- (boundary - linear_backoff_thresh) * TCP_RTO_MAX;
- timeout = jiffies_to_msecs(timeout);
- }
return (s32)(tcp_time_stamp(tcp_sk(sk)) - start_ts - timeout) >= 0;
}
@@ -226,7 +214,7 @@ static int tcp_write_timeout(struct sock *sk)
if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
if (icsk->icsk_retransmits) {
dst_negative_advice(sk);
- } else if (!tp->syn_data && !tp->syn_fastopen) {
+ } else {
sk_rethink_txhash(sk);
}
retry_until = icsk->icsk_syn_retries ? : net->ipv4.sysctl_tcp_syn_retries;
@@ -289,14 +277,14 @@ void tcp_delack_timer_handler(struct sock *sk)
icsk->icsk_ack.pending &= ~ICSK_ACK_TIMER;
if (inet_csk_ack_scheduled(sk)) {
- if (!icsk->icsk_ack.pingpong) {
+ if (!inet_csk_in_pingpong_mode(sk)) {
/* Delayed ACK missed: inflate ATO. */
icsk->icsk_ack.ato = min(icsk->icsk_ack.ato << 1, icsk->icsk_rto);
} else {
/* Delayed ACK missed: leave pingpong mode and
* deflate ATO.
*/
- icsk->icsk_ack.pingpong = 0;
+ inet_csk_exit_pingpong_mode(sk);
icsk->icsk_ack.ato = TCP_ATO_MIN;
}
tcp_mstamp_refresh(tcp_sk(sk));
@@ -345,7 +333,6 @@ static void tcp_probe_timer(struct sock *sk)
struct sk_buff *skb = tcp_send_head(sk);
struct tcp_sock *tp = tcp_sk(sk);
int max_probes;
- u32 start_ts;
if (tp->packets_out || !skb) {
icsk->icsk_probes_out = 0;
@@ -360,12 +347,13 @@ static void tcp_probe_timer(struct sock *sk)
* corresponding system limit. We also implement similar policy when
* we use RTO to probe window in tcp_retransmit_timer().
*/
- start_ts = tcp_skb_timestamp(skb);
- if (!start_ts)
- skb->skb_mstamp_ns = tp->tcp_clock_cache;
- else if (icsk->icsk_user_timeout &&
- (s32)(tcp_time_stamp(tp) - start_ts) > icsk->icsk_user_timeout)
- goto abort;
+ if (icsk->icsk_user_timeout) {
+ u32 elapsed = tcp_model_timeout(sk, icsk->icsk_probes_out,
+ tcp_probe0_base(sk));
+
+ if (elapsed >= icsk->icsk_user_timeout)
+ goto abort;
+ }
max_probes = sock_net(sk)->ipv4.sysctl_tcp_retries2;
if (sock_flag(sk, SOCK_DEAD)) {
@@ -395,6 +383,7 @@ static void tcp_fastopen_synack_timer(struct sock *sk)
struct inet_connection_sock *icsk = inet_csk(sk);
int max_retries = icsk->icsk_syn_retries ? :
sock_net(sk)->ipv4.sysctl_tcp_synack_retries + 1; /* add one more retry for fastopen */
+ struct tcp_sock *tp = tcp_sk(sk);
struct request_sock *req;
req = tcp_sk(sk)->fastopen_rsk;
@@ -412,6 +401,8 @@ static void tcp_fastopen_synack_timer(struct sock *sk)
inet_rtx_syn_ack(sk, req);
req->num_timeout++;
icsk->icsk_retransmits++;
+ if (!tp->retrans_stamp)
+ tp->retrans_stamp = tcp_time_stamp(tp);
inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS,
TCP_TIMEOUT_INIT << req->num_timeout, TCP_RTO_MAX);
}
@@ -443,10 +434,8 @@ void tcp_retransmit_timer(struct sock *sk)
*/
return;
}
- if (!tp->packets_out)
- goto out;
-
- WARN_ON(tcp_rtx_queue_empty(sk));
+ if (!tp->packets_out || WARN_ON_ONCE(tcp_rtx_queue_empty(sk)))
+ return;
tp->tlp_high_seq = 0;
@@ -511,14 +500,13 @@ void tcp_retransmit_timer(struct sock *sk)
tcp_enter_loss(sk);
+ icsk->icsk_retransmits++;
if (tcp_retransmit_skb(sk, tcp_rtx_queue_head(sk), 1) > 0) {
/* Retransmission failed because of local congestion,
- * do not backoff.
+ * Let senders fight for local resources conservatively.
*/
- if (!icsk->icsk_retransmits)
- icsk->icsk_retransmits = 1;
inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS,
- min(icsk->icsk_rto, TCP_RESOURCE_PROBE_INTERVAL),
+ TCP_RESOURCE_PROBE_INTERVAL,
TCP_RTO_MAX);
goto out;
}
@@ -539,7 +527,6 @@ void tcp_retransmit_timer(struct sock *sk)
* the 120 second clamps though!
*/
icsk->icsk_backoff++;
- icsk->icsk_retransmits++;
out_reset_timer:
/* If stream is thin, use linear timeouts. Since 'icsk_backoff' is
generated by cgit v1.2.3 (git 2.39.0) at 2024-11-24 19:17:44 +0300