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Diffstat (limited to 'net/ipv4/tcp_output.c')
-rw-r--r--net/ipv4/tcp_output.c324
1 files changed, 192 insertions, 132 deletions
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index 5a42e873d44a..540b7d92cc70 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -41,40 +41,25 @@
#include <linux/compiler.h>
#include <linux/gfp.h>
#include <linux/module.h>
+#include <linux/static_key.h>
-/* People can turn this off for buggy TCP's found in printers etc. */
-int sysctl_tcp_retrans_collapse __read_mostly = 1;
-
-/* People can turn this on to work with those rare, broken TCPs that
- * interpret the window field as a signed quantity.
- */
-int sysctl_tcp_workaround_signed_windows __read_mostly = 0;
-
-/* Default TSQ limit of four TSO segments */
-int sysctl_tcp_limit_output_bytes __read_mostly = 262144;
-
-/* This limits the percentage of the congestion window which we
- * will allow a single TSO frame to consume. Building TSO frames
- * which are too large can cause TCP streams to be bursty.
- */
-int sysctl_tcp_tso_win_divisor __read_mostly = 3;
-
-/* By default, RFC2861 behavior. */
-int sysctl_tcp_slow_start_after_idle __read_mostly = 1;
+#include <trace/events/tcp.h>
static bool tcp_write_xmit(struct sock *sk, unsigned int mss_now, int nonagle,
int push_one, gfp_t gfp);
/* Account for new data that has been sent to the network. */
-static void tcp_event_new_data_sent(struct sock *sk, const struct sk_buff *skb)
+static void tcp_event_new_data_sent(struct sock *sk, struct sk_buff *skb)
{
struct inet_connection_sock *icsk = inet_csk(sk);
struct tcp_sock *tp = tcp_sk(sk);
unsigned int prior_packets = tp->packets_out;
- tcp_advance_send_head(sk, skb);
tp->snd_nxt = TCP_SKB_CB(skb)->end_seq;
+ __skb_unlink(skb, &sk->sk_write_queue);
+ tcp_rbtree_insert(&sk->tcp_rtx_queue, skb);
+
tp->packets_out += tcp_skb_pcount(skb);
if (!prior_packets || icsk->icsk_pending == ICSK_TIME_LOSS_PROBE)
tcp_rearm_rto(sk);
@@ -203,7 +188,7 @@ u32 tcp_default_init_rwnd(u32 mss)
* be a multiple of mss if possible. We assume here that mss >= 1.
* This MUST be enforced by all callers.
*/
-void tcp_select_initial_window(int __space, __u32 mss,
+void tcp_select_initial_window(const struct sock *sk, int __space, __u32 mss,
__u32 *rcv_wnd, __u32 *window_clamp,
int wscale_ok, __u8 *rcv_wscale,
__u32 init_rcv_wnd)
@@ -227,7 +212,7 @@ void tcp_select_initial_window(int __space, __u32 mss,
* which we interpret as a sign the remote TCP is not
* misinterpreting the window field as a signed quantity.
*/
- if (sysctl_tcp_workaround_signed_windows)
+ if (sock_net(sk)->ipv4.sysctl_tcp_workaround_signed_windows)
(*rcv_wnd) = min(space, MAX_TCP_WINDOW);
else
(*rcv_wnd) = space;
@@ -235,7 +220,7 @@ void tcp_select_initial_window(int __space, __u32 mss,
(*rcv_wscale) = 0;
if (wscale_ok) {
/* Set window scaling on max possible window */
- space = max_t(u32, space, sysctl_tcp_rmem[2]);
+ space = max_t(u32, space, sock_net(sk)->ipv4.sysctl_tcp_rmem[2]);
space = max_t(u32, space, sysctl_rmem_max);
space = min_t(u32, space, *window_clamp);
while (space > U16_MAX && (*rcv_wscale) < TCP_MAX_WSCALE) {
@@ -287,7 +272,8 @@ static u16 tcp_select_window(struct sock *sk)
/* Make sure we do not exceed the maximum possible
* scaled window.
*/
- if (!tp->rx_opt.rcv_wscale && sysctl_tcp_workaround_signed_windows)
+ if (!tp->rx_opt.rcv_wscale &&
+ sock_net(sk)->ipv4.sysctl_tcp_workaround_signed_windows)
new_win = min(new_win, MAX_TCP_WINDOW);
else
new_win = min(new_win, (65535U << tp->rx_opt.rcv_wscale));
@@ -395,7 +381,6 @@ static void tcp_ecn_send(struct sock *sk, struct sk_buff *skb,
static void tcp_init_nondata_skb(struct sk_buff *skb, u32 seq, u8 flags)
{
skb->ip_summed = CHECKSUM_PARTIAL;
- skb->csum = 0;
TCP_SKB_CB(skb)->tcp_flags = flags;
TCP_SKB_CB(skb)->sacked = 0;
@@ -418,6 +403,22 @@ static inline bool tcp_urg_mode(const struct tcp_sock *tp)
#define OPTION_MD5 (1 << 2)
#define OPTION_WSCALE (1 << 3)
#define OPTION_FAST_OPEN_COOKIE (1 << 8)
+#define OPTION_SMC (1 << 9)
+
+static void smc_options_write(__be32 *ptr, u16 *options)
+{
+#if IS_ENABLED(CONFIG_SMC)
+ if (static_branch_unlikely(&tcp_have_smc)) {
+ if (unlikely(OPTION_SMC & *options)) {
+ *ptr++ = htonl((TCPOPT_NOP << 24) |
+ (TCPOPT_NOP << 16) |
+ (TCPOPT_EXP << 8) |
+ (TCPOLEN_EXP_SMC_BASE));
+ *ptr++ = htonl(TCPOPT_SMC_MAGIC);
+ }
+ }
+#endif
+}
struct tcp_out_options {
u16 options; /* bit field of OPTION_* */
@@ -536,6 +537,41 @@ static void tcp_options_write(__be32 *ptr, struct tcp_sock *tp,
}
ptr += (len + 3) >> 2;
}
+
+ smc_options_write(ptr, &options);
+}
+
+static void smc_set_option(const struct tcp_sock *tp,
+ struct tcp_out_options *opts,
+ unsigned int *remaining)
+{
+#if IS_ENABLED(CONFIG_SMC)
+ if (static_branch_unlikely(&tcp_have_smc)) {
+ if (tp->syn_smc) {
+ if (*remaining >= TCPOLEN_EXP_SMC_BASE_ALIGNED) {
+ opts->options |= OPTION_SMC;
+ *remaining -= TCPOLEN_EXP_SMC_BASE_ALIGNED;
+ }
+ }
+ }
+#endif
+}
+
+static void smc_set_option_cond(const struct tcp_sock *tp,
+ const struct inet_request_sock *ireq,
+ struct tcp_out_options *opts,
+ unsigned int *remaining)
+{
+#if IS_ENABLED(CONFIG_SMC)
+ if (static_branch_unlikely(&tcp_have_smc)) {
+ if (tp->syn_smc && ireq->smc_ok) {
+ if (*remaining >= TCPOLEN_EXP_SMC_BASE_ALIGNED) {
+ opts->options |= OPTION_SMC;
+ *remaining -= TCPOLEN_EXP_SMC_BASE_ALIGNED;
+ }
+ }
+ }
+#endif
}
/* Compute TCP options for SYN packets. This is not the final
@@ -603,11 +639,14 @@ static unsigned int tcp_syn_options(struct sock *sk, struct sk_buff *skb,
}
}
+ smc_set_option(tp, opts, &remaining);
+
return MAX_TCP_OPTION_SPACE - remaining;
}
/* Set up TCP options for SYN-ACKs. */
-static unsigned int tcp_synack_options(struct request_sock *req,
+static unsigned int tcp_synack_options(const struct sock *sk,
+ struct request_sock *req,
unsigned int mss, struct sk_buff *skb,
struct tcp_out_options *opts,
const struct tcp_md5sig_key *md5,
@@ -663,6 +702,8 @@ static unsigned int tcp_synack_options(struct request_sock *req,
}
}
+ smc_set_option_cond(tcp_sk(sk), ireq, opts, &remaining);
+
return MAX_TCP_OPTION_SPACE - remaining;
}
@@ -973,6 +1014,12 @@ static void tcp_internal_pacing(struct sock *sk, const struct sk_buff *skb)
HRTIMER_MODE_ABS_PINNED);
}
+static void tcp_update_skb_after_send(struct tcp_sock *tp, struct sk_buff *skb)
+{
+ skb->skb_mstamp = tp->tcp_mstamp;
+ list_move_tail(&skb->tcp_tsorted_anchor, &tp->tsorted_sent_queue);
+}
+
/* This routine actually transmits TCP packets queued in by
* tcp_do_sendmsg(). This is used by both the initial
* transmission and possible later retransmissions.
@@ -1005,10 +1052,14 @@ static int tcp_transmit_skb(struct sock *sk, struct sk_buff *skb, int clone_it,
TCP_SKB_CB(skb)->tx.in_flight = TCP_SKB_CB(skb)->end_seq
- tp->snd_una;
oskb = skb;
- if (unlikely(skb_cloned(skb)))
- skb = pskb_copy(skb, gfp_mask);
- else
- skb = skb_clone(skb, gfp_mask);
+
+ tcp_skb_tsorted_save(oskb) {
+ if (unlikely(skb_cloned(oskb)))
+ skb = pskb_copy(oskb, gfp_mask);
+ else
+ skb = skb_clone(oskb, gfp_mask);
+ } tcp_skb_tsorted_restore(oskb);
+
if (unlikely(!skb))
return -ENOBUFS;
}
@@ -1129,7 +1180,7 @@ static int tcp_transmit_skb(struct sock *sk, struct sk_buff *skb, int clone_it,
err = net_xmit_eval(err);
}
if (!err && oskb) {
- oskb->skb_mstamp = tp->tcp_mstamp;
+ tcp_update_skb_after_send(tp, oskb);
tcp_rate_skb_sent(sk, oskb);
}
return err;
@@ -1167,21 +1218,6 @@ static void tcp_set_skb_tso_segs(struct sk_buff *skb, unsigned int mss_now)
}
}
-/* When a modification to fackets out becomes necessary, we need to check
- * skb is counted to fackets_out or not.
- */
-static void tcp_adjust_fackets_out(struct sock *sk, const struct sk_buff *skb,
- int decr)
-{
- struct tcp_sock *tp = tcp_sk(sk);
-
- if (!tp->sacked_out || tcp_is_reno(tp))
- return;
-
- if (after(tcp_highest_sack_seq(tp), TCP_SKB_CB(skb)->seq))
- tp->fackets_out -= decr;
-}
-
/* Pcount in the middle of the write queue got changed, we need to do various
* tweaks to fix counters
*/
@@ -1202,11 +1238,9 @@ static void tcp_adjust_pcount(struct sock *sk, const struct sk_buff *skb, int de
if (tcp_is_reno(tp) && decr > 0)
tp->sacked_out -= min_t(u32, tp->sacked_out, decr);
- tcp_adjust_fackets_out(sk, skb, decr);
-
if (tp->lost_skb_hint &&
before(TCP_SKB_CB(skb)->seq, TCP_SKB_CB(tp->lost_skb_hint)->seq) &&
- (tcp_is_fack(tp) || (TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_ACKED)))
+ (TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_ACKED))
tp->lost_cnt_hint -= decr;
tcp_verify_left_out(tp);
@@ -1241,12 +1275,25 @@ static void tcp_skb_fragment_eor(struct sk_buff *skb, struct sk_buff *skb2)
TCP_SKB_CB(skb)->eor = 0;
}
+/* Insert buff after skb on the write or rtx queue of sk. */
+static void tcp_insert_write_queue_after(struct sk_buff *skb,
+ struct sk_buff *buff,
+ struct sock *sk,
+ enum tcp_queue tcp_queue)
+{
+ if (tcp_queue == TCP_FRAG_IN_WRITE_QUEUE)
+ __skb_queue_after(&sk->sk_write_queue, skb, buff);
+ else
+ tcp_rbtree_insert(&sk->tcp_rtx_queue, buff);
+}
+
/* Function to create two new TCP segments. Shrinks the given segment
* to the specified size and appends a new segment with the rest of the
* packet to the list. This won't be called frequently, I hope.
* Remember, these are still headerless SKBs at this point.
*/
-int tcp_fragment(struct sock *sk, struct sk_buff *skb, u32 len,
+int tcp_fragment(struct sock *sk, enum tcp_queue tcp_queue,
+ struct sk_buff *skb, u32 len,
unsigned int mss_now, gfp_t gfp)
{
struct tcp_sock *tp = tcp_sk(sk);
@@ -1329,7 +1376,9 @@ int tcp_fragment(struct sock *sk, struct sk_buff *skb, u32 len,
/* Link BUFF into the send queue. */
__skb_header_release(buff);
- tcp_insert_write_queue_after(skb, buff, sk);
+ tcp_insert_write_queue_after(skb, buff, sk, tcp_queue);
+ if (tcp_queue == TCP_FRAG_IN_RTX_QUEUE)
+ list_add(&buff->tcp_tsorted_anchor, &skb->tcp_tsorted_anchor);
return 0;
}
@@ -1607,7 +1656,7 @@ static void tcp_cwnd_validate(struct sock *sk, bool is_cwnd_limited)
if (tp->packets_out > tp->snd_cwnd_used)
tp->snd_cwnd_used = tp->packets_out;
- if (sysctl_tcp_slow_start_after_idle &&
+ if (sock_net(sk)->ipv4.sysctl_tcp_slow_start_after_idle &&
(s32)(tcp_jiffies32 - tp->snd_cwnd_stamp) >= inet_csk(sk)->icsk_rto &&
!ca_ops->cong_control)
tcp_cwnd_application_limited(sk);
@@ -1616,10 +1665,10 @@ static void tcp_cwnd_validate(struct sock *sk, bool is_cwnd_limited)
* is caused by insufficient sender buffer:
* 1) just sent some data (see tcp_write_xmit)
* 2) not cwnd limited (this else condition)
- * 3) no more data to send (null tcp_send_head )
+ * 3) no more data to send (tcp_write_queue_empty())
* 4) application is hitting buffer limit (SOCK_NOSPACE)
*/
- if (!tcp_send_head(sk) && sk->sk_socket &&
+ if (tcp_write_queue_empty(sk) && sk->sk_socket &&
test_bit(SOCK_NOSPACE, &sk->sk_socket->flags) &&
(1 << sk->sk_state) & (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT))
tcp_chrono_start(sk, TCP_CHRONO_SNDBUF_LIMITED);
@@ -1671,7 +1720,7 @@ u32 tcp_tso_autosize(const struct sock *sk, unsigned int mss_now,
{
u32 bytes, segs;
- bytes = min(sk->sk_pacing_rate >> 10,
+ bytes = min(sk->sk_pacing_rate >> sk->sk_pacing_shift,
sk->sk_gso_max_size - 1 - MAX_TCP_HEADER);
/* Goal is to send at least one packet per ms,
@@ -1694,7 +1743,8 @@ static u32 tcp_tso_segs(struct sock *sk, unsigned int mss_now)
u32 tso_segs = ca_ops->tso_segs_goal ? ca_ops->tso_segs_goal(sk) : 0;
return tso_segs ? :
- tcp_tso_autosize(sk, mss_now, sysctl_tcp_min_tso_segs);
+ tcp_tso_autosize(sk, mss_now,
+ sock_net(sk)->ipv4.sysctl_tcp_min_tso_segs);
}
/* Returns the portion of skb which can be sent right away */
@@ -1815,7 +1865,8 @@ static bool tcp_snd_wnd_test(const struct tcp_sock *tp,
* know that all the data is in scatter-gather pages, and that the
* packet has never been sent out before (and thus is not cloned).
*/
-static int tso_fragment(struct sock *sk, struct sk_buff *skb, unsigned int len,
+static int tso_fragment(struct sock *sk, enum tcp_queue tcp_queue,
+ struct sk_buff *skb, unsigned int len,
unsigned int mss_now, gfp_t gfp)
{
struct sk_buff *buff;
@@ -1824,7 +1875,7 @@ static int tso_fragment(struct sock *sk, struct sk_buff *skb, unsigned int len,
/* All of a TSO frame must be composed of paged data. */
if (skb->len != skb->data_len)
- return tcp_fragment(sk, skb, len, mss_now, gfp);
+ return tcp_fragment(sk, tcp_queue, skb, len, mss_now, gfp);
buff = sk_stream_alloc_skb(sk, 0, gfp, true);
if (unlikely(!buff))
@@ -1860,7 +1911,7 @@ static int tso_fragment(struct sock *sk, struct sk_buff *skb, unsigned int len,
/* Link BUFF into the send queue. */
__skb_header_release(buff);
- tcp_insert_write_queue_after(skb, buff, sk);
+ tcp_insert_write_queue_after(skb, buff, sk, tcp_queue);
return 0;
}
@@ -1910,7 +1961,7 @@ static bool tcp_tso_should_defer(struct sock *sk, struct sk_buff *skb,
if ((skb != tcp_write_queue_tail(sk)) && (limit >= skb->len))
goto send_now;
- win_divisor = READ_ONCE(sysctl_tcp_tso_win_divisor);
+ win_divisor = READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_tso_win_divisor);
if (win_divisor) {
u32 chunk = min(tp->snd_wnd, tp->snd_cwnd * tp->mss_cache);
@@ -1930,8 +1981,10 @@ static bool tcp_tso_should_defer(struct sock *sk, struct sk_buff *skb,
goto send_now;
}
- head = tcp_write_queue_head(sk);
-
+ /* TODO : use tsorted_sent_queue ? */
+ head = tcp_rtx_queue_head(sk);
+ if (!head)
+ goto send_now;
age = tcp_stamp_us_delta(tp->tcp_mstamp, head->skb_mstamp);
/* If next ACK is likely to come too late (half srtt), do not defer */
if (age < (tp->srtt_us >> 4))
@@ -2145,18 +2198,18 @@ static bool tcp_small_queue_check(struct sock *sk, const struct sk_buff *skb,
{
unsigned int limit;
- limit = max(2 * skb->truesize, sk->sk_pacing_rate >> 10);
- limit = min_t(u32, limit, sysctl_tcp_limit_output_bytes);
+ limit = max(2 * skb->truesize, sk->sk_pacing_rate >> sk->sk_pacing_shift);
+ limit = min_t(u32, limit,
+ sock_net(sk)->ipv4.sysctl_tcp_limit_output_bytes);
limit <<= factor;
if (refcount_read(&sk->sk_wmem_alloc) > limit) {
- /* Always send the 1st or 2nd skb in write queue.
+ /* Always send skb if rtx queue is empty.
* No need to wait for TX completion to call us back,
* after softirq/tasklet schedule.
* This helps when TX completions are delayed too much.
*/
- if (skb == sk->sk_write_queue.next ||
- skb->prev == sk->sk_write_queue.next)
+ if (tcp_rtx_queue_empty(sk))
return false;
set_bit(TSQ_THROTTLED, &sk->sk_tsq_flags);
@@ -2207,7 +2260,7 @@ void tcp_chrono_stop(struct sock *sk, const enum tcp_chrono type)
* it's the "most interesting" or current chrono we are
* tracking and starts busy chrono if we have pending data.
*/
- if (tcp_write_queue_empty(sk))
+ if (tcp_rtx_and_write_queues_empty(sk))
tcp_chrono_set(tp, TCP_CHRONO_UNSPEC);
else if (type == tp->chrono_type)
tcp_chrono_set(tp, TCP_CHRONO_BUSY);
@@ -2263,7 +2316,7 @@ static bool tcp_write_xmit(struct sock *sk, unsigned int mss_now, int nonagle,
if (unlikely(tp->repair) && tp->repair_queue == TCP_SEND_QUEUE) {
/* "skb_mstamp" is used as a start point for the retransmit timer */
- skb->skb_mstamp = tp->tcp_mstamp;
+ tcp_update_skb_after_send(tp, skb);
goto repair; /* Skip network transmission */
}
@@ -2302,7 +2355,8 @@ static bool tcp_write_xmit(struct sock *sk, unsigned int mss_now, int nonagle,
nonagle);
if (skb->len > limit &&
- unlikely(tso_fragment(sk, skb, limit, mss_now, gfp)))
+ unlikely(tso_fragment(sk, TCP_FRAG_IN_WRITE_QUEUE,
+ skb, limit, mss_now, gfp)))
break;
if (test_bit(TCP_TSQ_DEFERRED, &sk->sk_tsq_flags))
@@ -2342,7 +2396,7 @@ repair:
tcp_cwnd_validate(sk, is_cwnd_limited);
return false;
}
- return !tp->packets_out && tcp_send_head(sk);
+ return !tp->packets_out && !tcp_write_queue_empty(sk);
}
bool tcp_schedule_loss_probe(struct sock *sk)
@@ -2350,6 +2404,7 @@ bool tcp_schedule_loss_probe(struct sock *sk)
struct inet_connection_sock *icsk = inet_csk(sk);
struct tcp_sock *tp = tcp_sk(sk);
u32 timeout, rto_delta_us;
+ int early_retrans;
/* Don't do any loss probe on a Fast Open connection before 3WHS
* finishes.
@@ -2357,16 +2412,17 @@ bool tcp_schedule_loss_probe(struct sock *sk)
if (tp->fastopen_rsk)
return false;
+ early_retrans = sock_net(sk)->ipv4.sysctl_tcp_early_retrans;
/* Schedule a loss probe in 2*RTT for SACK capable connections
* in Open state, that are either limited by cwnd or application.
*/
- if ((sysctl_tcp_early_retrans != 3 && sysctl_tcp_early_retrans != 4) ||
+ if ((early_retrans != 3 && early_retrans != 4) ||
!tp->packets_out || !tcp_is_sack(tp) ||
icsk->icsk_ca_state != TCP_CA_Open)
return false;
if ((tp->snd_cwnd > tcp_packets_in_flight(tp)) &&
- tcp_send_head(sk))
+ !tcp_write_queue_empty(sk))
return false;
/* Probe timeout is 2*rtt. Add minimum RTO to account
@@ -2419,18 +2475,14 @@ void tcp_send_loss_probe(struct sock *sk)
int mss = tcp_current_mss(sk);
skb = tcp_send_head(sk);
- if (skb) {
- if (tcp_snd_wnd_test(tp, skb, mss)) {
- pcount = tp->packets_out;
- tcp_write_xmit(sk, mss, TCP_NAGLE_OFF, 2, GFP_ATOMIC);
- if (tp->packets_out > pcount)
- goto probe_sent;
- goto rearm_timer;
- }
- skb = tcp_write_queue_prev(sk, skb);
- } else {
- skb = tcp_write_queue_tail(sk);
+ if (skb && tcp_snd_wnd_test(tp, skb, mss)) {
+ pcount = tp->packets_out;
+ tcp_write_xmit(sk, mss, TCP_NAGLE_OFF, 2, GFP_ATOMIC);
+ if (tp->packets_out > pcount)
+ goto probe_sent;
+ goto rearm_timer;
}
+ skb = skb_rb_last(&sk->tcp_rtx_queue);
/* At most one outstanding TLP retransmission. */
if (tp->tlp_high_seq)
@@ -2448,10 +2500,11 @@ void tcp_send_loss_probe(struct sock *sk)
goto rearm_timer;
if ((pcount > 1) && (skb->len > (pcount - 1) * mss)) {
- if (unlikely(tcp_fragment(sk, skb, (pcount - 1) * mss, mss,
+ if (unlikely(tcp_fragment(sk, TCP_FRAG_IN_RTX_QUEUE, skb,
+ (pcount - 1) * mss, mss,
GFP_ATOMIC)))
goto rearm_timer;
- skb = tcp_write_queue_next(sk, skb);
+ skb = skb_rb_next(skb);
}
if (WARN_ON(!skb || !tcp_skb_pcount(skb)))
@@ -2651,7 +2704,7 @@ void tcp_skb_collapse_tstamp(struct sk_buff *skb,
static bool tcp_collapse_retrans(struct sock *sk, struct sk_buff *skb)
{
struct tcp_sock *tp = tcp_sk(sk);
- struct sk_buff *next_skb = tcp_write_queue_next(sk, skb);
+ struct sk_buff *next_skb = skb_rb_next(skb);
int skb_size, next_skb_size;
skb_size = skb->len;
@@ -2668,8 +2721,6 @@ static bool tcp_collapse_retrans(struct sock *sk, struct sk_buff *skb)
}
tcp_highest_sack_replace(sk, next_skb, skb);
- tcp_unlink_write_queue(next_skb, sk);
-
if (next_skb->ip_summed == CHECKSUM_PARTIAL)
skb->ip_summed = CHECKSUM_PARTIAL;
@@ -2697,7 +2748,7 @@ static bool tcp_collapse_retrans(struct sock *sk, struct sk_buff *skb)
tcp_skb_collapse_tstamp(skb, next_skb);
- sk_wmem_free_skb(sk, next_skb);
+ tcp_rtx_queue_unlink_and_free(next_skb, sk);
return true;
}
@@ -2708,8 +2759,6 @@ static bool tcp_can_collapse(const struct sock *sk, const struct sk_buff *skb)
return false;
if (skb_cloned(skb))
return false;
- if (skb == tcp_send_head(sk))
- return false;
/* Some heuristics for collapsing over SACK'd could be invented */
if (TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_ACKED)
return false;
@@ -2727,12 +2776,12 @@ static void tcp_retrans_try_collapse(struct sock *sk, struct sk_buff *to,
struct sk_buff *skb = to, *tmp;
bool first = true;
- if (!sysctl_tcp_retrans_collapse)
+ if (!sock_net(sk)->ipv4.sysctl_tcp_retrans_collapse)
return;
if (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_SYN)
return;
- tcp_for_write_queue_from_safe(skb, tmp, sk) {
+ skb_rbtree_walk_from_safe(skb, tmp) {
if (!tcp_can_collapse(sk, skb))
break;
@@ -2807,7 +2856,8 @@ int __tcp_retransmit_skb(struct sock *sk, struct sk_buff *skb, int segs)
len = cur_mss * segs;
if (skb->len > len) {
- if (tcp_fragment(sk, skb, len, cur_mss, GFP_ATOMIC))
+ if (tcp_fragment(sk, TCP_FRAG_IN_RTX_QUEUE, skb, len,
+ cur_mss, GFP_ATOMIC))
return -ENOMEM; /* We'll try again later. */
} else {
if (skb_unclone(skb, GFP_ATOMIC))
@@ -2841,11 +2891,14 @@ int __tcp_retransmit_skb(struct sock *sk, struct sk_buff *skb, int segs)
skb_headroom(skb) >= 0xFFFF)) {
struct sk_buff *nskb;
- nskb = __pskb_copy(skb, MAX_TCP_HEADER, GFP_ATOMIC);
- err = nskb ? tcp_transmit_skb(sk, nskb, 0, GFP_ATOMIC) :
- -ENOBUFS;
+ tcp_skb_tsorted_save(skb) {
+ nskb = __pskb_copy(skb, MAX_TCP_HEADER, GFP_ATOMIC);
+ err = nskb ? tcp_transmit_skb(sk, nskb, 0, GFP_ATOMIC) :
+ -ENOBUFS;
+ } tcp_skb_tsorted_restore(skb);
+
if (!err) {
- skb->skb_mstamp = tp->tcp_mstamp;
+ tcp_update_skb_after_send(tp, skb);
tcp_rate_skb_sent(sk, skb);
}
} else {
@@ -2854,6 +2907,7 @@ int __tcp_retransmit_skb(struct sock *sk, struct sk_buff *skb, int segs)
if (likely(!err)) {
TCP_SKB_CB(skb)->sacked |= TCPCB_EVER_RETRANS;
+ trace_tcp_retransmit_skb(sk, skb);
} else if (err != -EBUSY) {
NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPRETRANSFAIL);
}
@@ -2890,36 +2944,25 @@ int tcp_retransmit_skb(struct sock *sk, struct sk_buff *skb, int segs)
* retransmitted data is acknowledged. It tries to continue
* resending the rest of the retransmit queue, until either
* we've sent it all or the congestion window limit is reached.
- * If doing SACK, the first ACK which comes back for a timeout
- * based retransmit packet might feed us FACK information again.
- * If so, we use it to avoid unnecessarily retransmissions.
*/
void tcp_xmit_retransmit_queue(struct sock *sk)
{
const struct inet_connection_sock *icsk = inet_csk(sk);
+ struct sk_buff *skb, *rtx_head, *hole = NULL;
struct tcp_sock *tp = tcp_sk(sk);
- struct sk_buff *skb;
- struct sk_buff *hole = NULL;
u32 max_segs;
int mib_idx;
if (!tp->packets_out)
return;
- if (tp->retransmit_skb_hint) {
- skb = tp->retransmit_skb_hint;
- } else {
- skb = tcp_write_queue_head(sk);
- }
-
+ rtx_head = tcp_rtx_queue_head(sk);
+ skb = tp->retransmit_skb_hint ?: rtx_head;
max_segs = tcp_tso_segs(sk, tcp_current_mss(sk));
- tcp_for_write_queue_from(skb, sk) {
+ skb_rbtree_walk_from(skb) {
__u8 sacked;
int segs;
- if (skb == tcp_send_head(sk))
- break;
-
if (tcp_pacing_check(sk))
break;
@@ -2964,7 +3007,7 @@ void tcp_xmit_retransmit_queue(struct sock *sk)
if (tcp_in_cwnd_reduction(sk))
tp->prr_out += tcp_skb_pcount(skb);
- if (skb == tcp_write_queue_head(sk) &&
+ if (skb == rtx_head &&
icsk->icsk_pending != ICSK_TIME_REO_TIMEOUT)
inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS,
inet_csk(sk)->icsk_rto,
@@ -3006,12 +3049,15 @@ 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) || tcp_under_memory_pressure(sk))) {
+ if (!tskb && tcp_under_memory_pressure(sk))
+ tskb = skb_rb_last(&sk->tcp_rtx_queue);
+
+ if (tskb) {
coalesce:
TCP_SKB_CB(tskb)->tcp_flags |= TCPHDR_FIN;
TCP_SKB_CB(tskb)->end_seq++;
tp->write_seq++;
- if (!tcp_send_head(sk)) {
+ if (tcp_write_queue_empty(sk)) {
/* This means tskb was already sent.
* Pretend we included the FIN on previous transmit.
* We need to set tp->snd_nxt to the value it would have
@@ -3028,6 +3074,7 @@ coalesce:
goto coalesce;
return;
}
+ INIT_LIST_HEAD(&skb->tcp_tsorted_anchor);
skb_reserve(skb, MAX_TCP_HEADER);
sk_forced_mem_schedule(sk, skb->truesize);
/* FIN eats a sequence byte, write_seq advanced by tcp_queue_skb(). */
@@ -3064,6 +3111,11 @@ void tcp_send_active_reset(struct sock *sk, gfp_t priority)
/* Send it off. */
if (tcp_transmit_skb(sk, skb, 0, priority))
NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPABORTFAILED);
+
+ /* skb of trace_tcp_send_reset() keeps the skb that caused RST,
+ * skb here is different to the troublesome skb, so use NULL
+ */
+ trace_tcp_send_reset(sk, NULL);
}
/* Send a crossed SYN-ACK during socket establishment.
@@ -3076,20 +3128,24 @@ int tcp_send_synack(struct sock *sk)
{
struct sk_buff *skb;
- skb = tcp_write_queue_head(sk);
+ skb = tcp_rtx_queue_head(sk);
if (!skb || !(TCP_SKB_CB(skb)->tcp_flags & TCPHDR_SYN)) {
- pr_debug("%s: wrong queue state\n", __func__);
+ pr_err("%s: wrong queue state\n", __func__);
return -EFAULT;
}
if (!(TCP_SKB_CB(skb)->tcp_flags & TCPHDR_ACK)) {
if (skb_cloned(skb)) {
- struct sk_buff *nskb = skb_copy(skb, GFP_ATOMIC);
+ struct sk_buff *nskb;
+
+ tcp_skb_tsorted_save(skb) {
+ nskb = skb_copy(skb, GFP_ATOMIC);
+ } tcp_skb_tsorted_restore(skb);
if (!nskb)
return -ENOMEM;
- tcp_unlink_write_queue(skb, sk);
+ INIT_LIST_HEAD(&nskb->tcp_tsorted_anchor);
+ tcp_rtx_queue_unlink_and_free(skb, sk);
__skb_header_release(nskb);
- __tcp_add_write_queue_head(sk, nskb);
- sk_wmem_free_skb(sk, skb);
+ tcp_rbtree_insert(&sk->tcp_rtx_queue, nskb);
sk->sk_wmem_queued += nskb->truesize;
sk_mem_charge(sk, nskb->truesize);
skb = nskb;
@@ -3166,8 +3222,8 @@ struct sk_buff *tcp_make_synack(const struct sock *sk, struct dst_entry *dst,
md5 = tcp_rsk(req)->af_specific->req_md5_lookup(sk, req_to_sk(req));
#endif
skb_set_hash(skb, tcp_rsk(req)->txhash, PKT_HASH_TYPE_L4);
- tcp_header_size = tcp_synack_options(req, mss, skb, &opts, md5, foc) +
- sizeof(*th);
+ tcp_header_size = tcp_synack_options(sk, req, mss, skb, &opts, md5,
+ foc) + sizeof(*th);
skb_push(skb, tcp_header_size);
skb_reset_transport_header(skb);
@@ -3268,7 +3324,7 @@ static void tcp_connect_init(struct sock *sk)
if (rcv_wnd == 0)
rcv_wnd = dst_metric(dst, RTAX_INITRWND);
- tcp_select_initial_window(tcp_full_space(sk),
+ tcp_select_initial_window(sk, tcp_full_space(sk),
tp->advmss - (tp->rx_opt.ts_recent_stamp ? tp->tcp_header_len - sizeof(struct tcphdr) : 0),
&tp->rcv_wnd,
&tp->window_clamp,
@@ -3307,7 +3363,6 @@ static void tcp_connect_queue_skb(struct sock *sk, struct sk_buff *skb)
tcb->end_seq += skb->len;
__skb_header_release(skb);
- __tcp_add_write_queue_tail(sk, skb);
sk->sk_wmem_queued += skb->truesize;
sk_mem_charge(sk, skb->truesize);
tp->write_seq = tcb->end_seq;
@@ -3355,6 +3410,7 @@ static int tcp_send_syn_data(struct sock *sk, struct sk_buff *syn)
int copied = copy_from_iter(skb_put(syn_data, space), space,
&fo->data->msg_iter);
if (unlikely(!copied)) {
+ tcp_skb_tsorted_anchor_cleanup(syn_data);
kfree_skb(syn_data);
goto fallback;
}
@@ -3385,12 +3441,13 @@ static int tcp_send_syn_data(struct sock *sk, struct sk_buff *syn)
TCP_SKB_CB(syn_data)->tcp_flags = TCPHDR_ACK | TCPHDR_PSH;
if (!err) {
tp->syn_data = (fo->copied > 0);
+ tcp_rbtree_insert(&sk->tcp_rtx_queue, syn_data);
NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPORIGDATASENT);
goto done;
}
- /* data was not sent, this is our new send_head */
- sk->sk_send_head = syn_data;
+ /* data was not sent, put it in write_queue */
+ __skb_queue_tail(&sk->sk_write_queue, syn_data);
tp->packets_out -= tcp_skb_pcount(syn_data);
fallback:
@@ -3433,6 +3490,7 @@ int tcp_connect(struct sock *sk)
tp->retrans_stamp = tcp_time_stamp(tp);
tcp_connect_queue_skb(sk, buff);
tcp_ecn_send_syn(sk, buff);
+ tcp_rbtree_insert(&sk->tcp_rtx_queue, buff);
/* Send off SYN; include data in Fast Open. */
err = tp->fastopen_req ? tcp_send_syn_data(sk, buff) :
@@ -3627,7 +3685,8 @@ int tcp_write_wakeup(struct sock *sk, int mib)
skb->len > mss) {
seg_size = min(seg_size, mss);
TCP_SKB_CB(skb)->tcp_flags |= TCPHDR_PSH;
- if (tcp_fragment(sk, skb, seg_size, mss, GFP_ATOMIC))
+ if (tcp_fragment(sk, TCP_FRAG_IN_WRITE_QUEUE,
+ skb, seg_size, mss, GFP_ATOMIC))
return -1;
} else if (!tcp_skb_pcount(skb))
tcp_set_skb_tso_segs(skb, mss);
@@ -3657,7 +3716,7 @@ void tcp_send_probe0(struct sock *sk)
err = tcp_write_wakeup(sk, LINUX_MIB_TCPWINPROBE);
- if (tp->packets_out || !tcp_send_head(sk)) {
+ if (tp->packets_out || tcp_write_queue_empty(sk)) {
/* Cancel probe timer, if it is not required. */
icsk->icsk_probes_out = 0;
icsk->icsk_backoff = 0;
@@ -3698,6 +3757,7 @@ int tcp_rtx_synack(const struct sock *sk, struct request_sock *req)
__NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPSYNRETRANS);
if (unlikely(tcp_passive_fastopen(sk)))
tcp_sk(sk)->total_retrans++;
+ trace_tcp_retransmit_synack(sk, req);
}
return res;
}