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Diffstat (limited to 'net/ipv4/tcp_output.c')
-rw-r--r--net/ipv4/tcp_output.c112
1 files changed, 51 insertions, 61 deletions
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index d07e34f8e309..8e08b409c71e 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -162,6 +162,15 @@ static void tcp_event_data_sent(struct tcp_sock *tp,
/* Account for an ACK we sent. */
static inline void tcp_event_ack_sent(struct sock *sk, unsigned int pkts)
{
+ struct tcp_sock *tp = tcp_sk(sk);
+
+ if (unlikely(tp->compressed_ack)) {
+ NET_ADD_STATS(sock_net(sk), LINUX_MIB_TCPACKCOMPRESSED,
+ tp->compressed_ack);
+ tp->compressed_ack = 0;
+ if (hrtimer_try_to_cancel(&tp->compressed_ack_timer) == 1)
+ __sock_put(sk);
+ }
tcp_dec_quickack_mode(sk, pkts);
inet_csk_clear_xmit_timer(sk, ICSK_TIME_DACK);
}
@@ -229,11 +238,9 @@ void tcp_select_initial_window(const struct sock *sk, int __space, __u32 mss,
}
}
- if (mss > (1 << *rcv_wscale)) {
- if (!init_rcv_wnd) /* Use default unless specified otherwise */
- init_rcv_wnd = tcp_default_init_rwnd(mss);
- *rcv_wnd = min(*rcv_wnd, init_rcv_wnd * mss);
- }
+ if (!init_rcv_wnd) /* Use default unless specified otherwise */
+ init_rcv_wnd = tcp_default_init_rwnd(mss);
+ *rcv_wnd = min(*rcv_wnd, init_rcv_wnd * mss);
/* Set the clamp no higher than max representable value */
(*window_clamp) = min_t(__u32, U16_MAX << (*rcv_wscale), *window_clamp);
@@ -585,14 +592,15 @@ static unsigned int tcp_syn_options(struct sock *sk, struct sk_buff *skb,
unsigned int remaining = MAX_TCP_OPTION_SPACE;
struct tcp_fastopen_request *fastopen = tp->fastopen_req;
+ *md5 = NULL;
#ifdef CONFIG_TCP_MD5SIG
- *md5 = tp->af_specific->md5_lookup(sk, sk);
- if (*md5) {
- opts->options |= OPTION_MD5;
- remaining -= TCPOLEN_MD5SIG_ALIGNED;
+ if (unlikely(rcu_access_pointer(tp->md5sig_info))) {
+ *md5 = tp->af_specific->md5_lookup(sk, sk);
+ if (*md5) {
+ opts->options |= OPTION_MD5;
+ remaining -= TCPOLEN_MD5SIG_ALIGNED;
+ }
}
-#else
- *md5 = NULL;
#endif
/* We always get an MSS option. The option bytes which will be seen in
@@ -720,14 +728,15 @@ static unsigned int tcp_established_options(struct sock *sk, struct sk_buff *skb
opts->options = 0;
+ *md5 = NULL;
#ifdef CONFIG_TCP_MD5SIG
- *md5 = tp->af_specific->md5_lookup(sk, sk);
- if (unlikely(*md5)) {
- opts->options |= OPTION_MD5;
- size += TCPOLEN_MD5SIG_ALIGNED;
+ if (unlikely(rcu_access_pointer(tp->md5sig_info))) {
+ *md5 = tp->af_specific->md5_lookup(sk, sk);
+ if (*md5) {
+ opts->options |= OPTION_MD5;
+ size += TCPOLEN_MD5SIG_ALIGNED;
+ }
}
-#else
- *md5 = NULL;
#endif
if (likely(tp->rx_opt.tstamp_ok)) {
@@ -772,7 +781,7 @@ struct tsq_tasklet {
};
static DEFINE_PER_CPU(struct tsq_tasklet, tsq_tasklet);
-static void tcp_tsq_handler(struct sock *sk)
+static void tcp_tsq_write(struct sock *sk)
{
if ((1 << sk->sk_state) &
(TCPF_ESTABLISHED | TCPF_FIN_WAIT1 | TCPF_CLOSING |
@@ -789,6 +798,16 @@ static void tcp_tsq_handler(struct sock *sk)
0, GFP_ATOMIC);
}
}
+
+static void tcp_tsq_handler(struct sock *sk)
+{
+ bh_lock_sock(sk);
+ if (!sock_owned_by_user(sk))
+ tcp_tsq_write(sk);
+ else if (!test_and_set_bit(TCP_TSQ_DEFERRED, &sk->sk_tsq_flags))
+ sock_hold(sk);
+ bh_unlock_sock(sk);
+}
/*
* One tasklet per cpu tries to send more skbs.
* We run in tasklet context but need to disable irqs when
@@ -816,16 +835,7 @@ static void tcp_tasklet_func(unsigned long data)
smp_mb__before_atomic();
clear_bit(TSQ_QUEUED, &sk->sk_tsq_flags);
- if (!sk->sk_lock.owned &&
- test_bit(TCP_TSQ_DEFERRED, &sk->sk_tsq_flags)) {
- bh_lock_sock(sk);
- if (!sock_owned_by_user(sk)) {
- clear_bit(TCP_TSQ_DEFERRED, &sk->sk_tsq_flags);
- tcp_tsq_handler(sk);
- }
- bh_unlock_sock(sk);
- }
-
+ tcp_tsq_handler(sk);
sk_free(sk);
}
}
@@ -853,9 +863,10 @@ void tcp_release_cb(struct sock *sk)
nflags = flags & ~TCP_DEFERRED_ALL;
} while (cmpxchg(&sk->sk_tsq_flags, flags, nflags) != flags);
- if (flags & TCPF_TSQ_DEFERRED)
- tcp_tsq_handler(sk);
-
+ if (flags & TCPF_TSQ_DEFERRED) {
+ tcp_tsq_write(sk);
+ __sock_put(sk);
+ }
/* Here begins the tricky part :
* We are called from release_sock() with :
* 1) BH disabled
@@ -929,7 +940,7 @@ void tcp_wfree(struct sk_buff *skb)
if (!(oval & TSQF_THROTTLED) || (oval & TSQF_QUEUED))
goto out;
- nval = (oval & ~TSQF_THROTTLED) | TSQF_QUEUED | TCPF_TSQ_DEFERRED;
+ nval = (oval & ~TSQF_THROTTLED) | TSQF_QUEUED;
nval = cmpxchg(&sk->sk_tsq_flags, oval, nval);
if (nval != oval)
continue;
@@ -948,37 +959,17 @@ out:
sk_free(sk);
}
-/* Note: Called under hard irq.
- * We can not call TCP stack right away.
+/* Note: Called under soft irq.
+ * We can call TCP stack right away, unless socket is owned by user.
*/
enum hrtimer_restart tcp_pace_kick(struct hrtimer *timer)
{
struct tcp_sock *tp = container_of(timer, struct tcp_sock, pacing_timer);
struct sock *sk = (struct sock *)tp;
- unsigned long nval, oval;
- for (oval = READ_ONCE(sk->sk_tsq_flags);; oval = nval) {
- struct tsq_tasklet *tsq;
- bool empty;
-
- if (oval & TSQF_QUEUED)
- break;
-
- nval = (oval & ~TSQF_THROTTLED) | TSQF_QUEUED | TCPF_TSQ_DEFERRED;
- nval = cmpxchg(&sk->sk_tsq_flags, oval, nval);
- if (nval != oval)
- continue;
+ tcp_tsq_handler(sk);
+ sock_put(sk);
- if (!refcount_inc_not_zero(&sk->sk_wmem_alloc))
- break;
- /* queue this socket to tasklet queue */
- tsq = this_cpu_ptr(&tsq_tasklet);
- empty = list_empty(&tsq->head);
- list_add(&tp->tsq_node, &tsq->head);
- if (empty)
- tasklet_schedule(&tsq->tasklet);
- break;
- }
return HRTIMER_NORESTART;
}
@@ -1011,7 +1002,8 @@ static void tcp_internal_pacing(struct sock *sk, const struct sk_buff *skb)
do_div(len_ns, rate);
hrtimer_start(&tcp_sk(sk)->pacing_timer,
ktime_add_ns(ktime_get(), len_ns),
- HRTIMER_MODE_ABS_PINNED);
+ HRTIMER_MODE_ABS_PINNED_SOFT);
+ sock_hold(sk);
}
static void tcp_update_skb_after_send(struct tcp_sock *tp, struct sk_buff *skb)
@@ -1078,7 +1070,7 @@ static int tcp_transmit_skb(struct sock *sk, struct sk_buff *skb, int clone_it,
/* if no packet is in qdisc/device queue, then allow XPS to select
* another queue. We can be called from tcp_tsq_handler()
- * which holds one reference to sk_wmem_alloc.
+ * which holds one reference to sk.
*
* TODO: Ideally, in-flight pure ACK packets should not matter here.
* One way to get this would be to set skb->truesize = 2 on them.
@@ -2185,7 +2177,7 @@ static int tcp_mtu_probe(struct sock *sk)
static bool tcp_pacing_check(const struct sock *sk)
{
return tcp_needs_internal_pacing(sk) &&
- hrtimer_active(&tcp_sk(sk)->pacing_timer);
+ hrtimer_is_queued(&tcp_sk(sk)->pacing_timer);
}
/* TCP Small Queues :
@@ -2365,8 +2357,6 @@ static bool tcp_write_xmit(struct sock *sk, unsigned int mss_now, int nonagle,
skb, limit, mss_now, gfp)))
break;
- if (test_bit(TCP_TSQ_DEFERRED, &sk->sk_tsq_flags))
- clear_bit(TCP_TSQ_DEFERRED, &sk->sk_tsq_flags);
if (tcp_small_queue_check(sk, skb, 0))
break;