return seq3 - seq2 >= seq1 - seq2;
}
-static inline int tcp_too_many_orphans(struct sock *sk, int num)
+static inline bool tcp_too_many_orphans(struct sock *sk, int shift)
{
- return (num > sysctl_tcp_max_orphans) ||
- (sk->sk_wmem_queued > SOCK_MIN_SNDBUF &&
- atomic_read(&tcp_memory_allocated) > sysctl_tcp_mem[2]);
+ struct percpu_counter *ocp = sk->sk_prot->orphan_count;
+ int orphans = percpu_counter_read_positive(ocp);
+
+ if (orphans << shift > sysctl_tcp_max_orphans) {
+ orphans = percpu_counter_sum_positive(ocp);
+ if (orphans << shift > sysctl_tcp_max_orphans)
+ return true;
+ }
+
+ if (sk->sk_wmem_queued > SOCK_MIN_SNDBUF &&
+ atomic_read(&tcp_memory_allocated) > sysctl_tcp_mem[2])
+ return true;
+ return false;
}
/* syncookies: remember time of last synqueue overflow */
/* Bound MSS / TSO packet size with the half of the window */
static inline int tcp_bound_to_half_wnd(struct tcp_sock *tp, int pktsize)
{
- if (tp->max_window && pktsize > (tp->max_window >> 1))
- return max(tp->max_window >> 1, 68U - tp->tcp_header_len);
+ int cutoff;
+
+ /* When peer uses tiny windows, there is no use in packetizing
+ * to sub-MSS pieces for the sake of SWS or making sure there
+ * are enough packets in the pipe for fast recovery.
+ *
+ * On the other hand, for extremely large MSS devices, handling
+ * smaller than MSS windows in this way does make sense.
+ */
+ if (tp->max_window >= 512)
+ cutoff = (tp->max_window >> 1);
+ else
+ cutoff = tp->max_window;
+
+ if (cutoff && pktsize > cutoff)
+ return max_t(int, cutoff, 68U - tp->tcp_header_len);
else
return pktsize;
}
/* Use define here intentionally to get WARN_ON location shown at the caller */
#define tcp_verify_left_out(tp) WARN_ON(tcp_left_out(tp) > tp->packets_out)
+/*
+ * Convert RFC 3390 larger initial window into an equivalent number of packets.
+ * This is based on the numbers specified in RFC 5681, 3.1.
+ */
+static inline u32 rfc3390_bytes_to_packets(const u32 smss)
+{
+ return smss <= 1095 ? 4 : (smss > 2190 ? 2 : 3);
+}
+
extern void tcp_enter_cwr(struct sock *sk, const int set_ssthresh);
extern __u32 tcp_init_cwnd(struct tcp_sock *tp, struct dst_entry *dst);