#include <net/ip.h>
#include <net/tcp_states.h>
#include <net/inet_ecn.h>
+#include <net/dst.h>
#include <linux/seq_file.h>
atomic_read(&tcp_memory_allocated) > sysctl_tcp_mem[2]);
}
+/* syncookies: remember time of last synqueue overflow */
+static inline void tcp_synq_overflow(struct sock *sk)
+{
+ tcp_sk(sk)->rx_opt.ts_recent_stamp = jiffies;
+}
+
+/* syncookies: no recent synqueue overflow on this listening socket? */
+static inline int tcp_synq_no_recent_overflow(const struct sock *sk)
+{
+ unsigned long last_overflow = tcp_sk(sk)->rx_opt.ts_recent_stamp;
+ return time_after(jiffies, last_overflow + TCP_TIMEOUT_INIT);
+}
+
extern struct proto tcp_prot;
#define TCP_INC_STATS(net, field) SNMP_INC_STATS((net)->mib.tcp_statistics, field)
tcp_fast_path_on(tp);
}
+/* Compute the actual rto_min value */
+static inline u32 tcp_rto_min(struct sock *sk)
+{
+ struct dst_entry *dst = __sk_dst_get(sk);
+ u32 rto_min = TCP_RTO_MIN;
+
+ if (dst && dst_metric_locked(dst, RTAX_RTO_MIN))
+ rto_min = dst_metric_rtt(dst, RTAX_RTO_MIN);
+ return rto_min;
+}
+
/* Compute the actual receive window we are currently advertising.
* Rcv_nxt can be after the window if our peer push more data
* than the offered window.
return skb_shinfo(skb)->gso_size;
}
-static inline void tcp_dec_pcount_approx_int(__u32 *count, const int decr)
-{
- if (*count) {
- *count -= decr;
- if ((int)*count < 0)
- *count = 0;
- }
-}
-
-static inline void tcp_dec_pcount_approx(__u32 *count,
- const struct sk_buff *skb)
-{
- tcp_dec_pcount_approx_int(count, tcp_skb_pcount(skb));
-}
-
/* Events passed to congestion control interface */
enum tcp_ca_event {
CA_EVENT_TX_START, /* first transmit when no packets in flight */
{
struct tcp_sock *tp = tcp_sk(sk);
- if (!sysctl_tcp_low_latency && tp->ucopy.task) {
- __skb_queue_tail(&tp->ucopy.prequeue, skb);
- tp->ucopy.memory += skb->truesize;
- if (tp->ucopy.memory > sk->sk_rcvbuf) {
- struct sk_buff *skb1;
-
- BUG_ON(sock_owned_by_user(sk));
-
- while ((skb1 = __skb_dequeue(&tp->ucopy.prequeue)) != NULL) {
- sk_backlog_rcv(sk, skb1);
- NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPPREQUEUEDROPPED);
- }
-
- tp->ucopy.memory = 0;
- } else if (skb_queue_len(&tp->ucopy.prequeue) == 1) {
- wake_up_interruptible(sk->sk_sleep);
- if (!inet_csk_ack_scheduled(sk))
- inet_csk_reset_xmit_timer(sk, ICSK_TIME_DACK,
- (3 * TCP_RTO_MIN) / 4,
- TCP_RTO_MAX);
+ if (sysctl_tcp_low_latency || !tp->ucopy.task)
+ return 0;
+
+ __skb_queue_tail(&tp->ucopy.prequeue, skb);
+ tp->ucopy.memory += skb->truesize;
+ if (tp->ucopy.memory > sk->sk_rcvbuf) {
+ struct sk_buff *skb1;
+
+ BUG_ON(sock_owned_by_user(sk));
+
+ while ((skb1 = __skb_dequeue(&tp->ucopy.prequeue)) != NULL) {
+ sk_backlog_rcv(sk, skb1);
+ NET_INC_STATS_BH(sock_net(sk),
+ LINUX_MIB_TCPPREQUEUEDROPPED);
}
- return 1;
+
+ tp->ucopy.memory = 0;
+ } else if (skb_queue_len(&tp->ucopy.prequeue) == 1) {
+ wake_up_interruptible_poll(sk->sk_sleep,
+ POLLIN | POLLRDNORM | POLLRDBAND);
+ if (!inet_csk_ack_scheduled(sk))
+ inet_csk_reset_xmit_timer(sk, ICSK_TIME_DACK,
+ (3 * tcp_rto_min(sk)) / 4,
+ TCP_RTO_MAX);
}
- return 0;
+ return 1;
}