#else
# define TCP_TW_RECYCLE_TICK (12+2-TCP_TW_RECYCLE_SLOTS_LOG)
#endif
-
-#define BICTCP_BETA_SCALE 1024 /* Scale factor beta calculation
- * max_cwnd = snd_cwnd * beta
- */
-#define BICTCP_MAX_INCREMENT 32 /*
- * Limit on the amount of
- * increment allowed during
- * binary search.
- */
-#define BICTCP_FUNC_OF_MIN_INCR 11 /*
- * log(B/Smin)/log(B/(B-1))+1,
- * Smin:min increment
- * B:log factor
- */
-#define BICTCP_B 4 /*
- * In binary search,
- * go to point (max+min)/N
- */
-
/*
* TCP option
*/
extern int sysctl_tcp_tw_reuse;
extern int sysctl_tcp_frto;
extern int sysctl_tcp_low_latency;
-extern int sysctl_tcp_westwood;
-extern int sysctl_tcp_vegas_cong_avoid;
-extern int sysctl_tcp_vegas_alpha;
-extern int sysctl_tcp_vegas_beta;
-extern int sysctl_tcp_vegas_gamma;
extern int sysctl_tcp_nometrics_save;
-extern int sysctl_tcp_bic;
-extern int sysctl_tcp_bic_fast_convergence;
-extern int sysctl_tcp_bic_low_window;
-extern int sysctl_tcp_bic_beta;
extern int sysctl_tcp_moderate_rcvbuf;
extern int sysctl_tcp_tso_win_divisor;
return tp->ack.pending&TCP_ACK_SCHED;
}
-static __inline__ void tcp_dec_quickack_mode(struct tcp_sock *tp)
+static __inline__ void tcp_dec_quickack_mode(struct tcp_sock *tp, unsigned int pkts)
{
- if (tp->ack.quick && --tp->ack.quick == 0) {
- /* Leaving quickack mode we deflate ATO. */
- tp->ack.ato = TCP_ATO_MIN;
+ if (tp->ack.quick) {
+ if (pkts >= tp->ack.quick) {
+ tp->ack.quick = 0;
+
+ /* Leaving quickack mode we deflate ATO. */
+ tp->ack.ato = TCP_ATO_MIN;
+ } else
+ tp->ack.quick -= pkts;
}
}
/* tcp_output.c */
extern int tcp_write_xmit(struct sock *, int nonagle);
+extern void __tcp_data_snd_check(struct sock *sk, struct sk_buff *skb);
+extern void __tcp_push_pending_frames(struct sock *sk, struct tcp_sock *tp,
+ unsigned cur_mss, int nonagle);
+extern int tcp_may_send_now(struct sock *sk, struct tcp_sock *tp);
extern int tcp_retransmit_skb(struct sock *, struct sk_buff *);
extern void tcp_xmit_retransmit_queue(struct sock *);
extern void tcp_simple_retransmit(struct sock *);
tp->packets_out -= 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 */
+ CA_EVENT_CWND_RESTART, /* congestion window restart */
+ CA_EVENT_COMPLETE_CWR, /* end of congestion recovery */
+ CA_EVENT_FRTO, /* fast recovery timeout */
+ CA_EVENT_LOSS, /* loss timeout */
+ CA_EVENT_FAST_ACK, /* in sequence ack */
+ CA_EVENT_SLOW_ACK, /* other ack */
+};
+
+/*
+ * Interface for adding new TCP congestion control handlers
+ */
+#define TCP_CA_NAME_MAX 16
+struct tcp_congestion_ops {
+ struct list_head list;
+
+ /* initialize private data (optional) */
+ void (*init)(struct tcp_sock *tp);
+ /* cleanup private data (optional) */
+ void (*release)(struct tcp_sock *tp);
+
+ /* return slow start threshold (required) */
+ u32 (*ssthresh)(struct tcp_sock *tp);
+ /* lower bound for congestion window (optional) */
+ u32 (*min_cwnd)(struct tcp_sock *tp);
+ /* do new cwnd calculation (required) */
+ void (*cong_avoid)(struct tcp_sock *tp, u32 ack,
+ u32 rtt, u32 in_flight, int good_ack);
+ /* round trip time sample per acked packet (optional) */
+ void (*rtt_sample)(struct tcp_sock *tp, u32 usrtt);
+ /* call before changing ca_state (optional) */
+ void (*set_state)(struct tcp_sock *tp, u8 new_state);
+ /* call when cwnd event occurs (optional) */
+ void (*cwnd_event)(struct tcp_sock *tp, enum tcp_ca_event ev);
+ /* new value of cwnd after loss (optional) */
+ u32 (*undo_cwnd)(struct tcp_sock *tp);
+ /* hook for packet ack accounting (optional) */
+ void (*pkts_acked)(struct tcp_sock *tp, u32 num_acked);
+ /* get info for tcp_diag (optional) */
+ void (*get_info)(struct tcp_sock *tp, u32 ext, struct sk_buff *skb);
+
+ char name[TCP_CA_NAME_MAX];
+ struct module *owner;
+};
+
+extern int tcp_register_congestion_control(struct tcp_congestion_ops *type);
+extern void tcp_unregister_congestion_control(struct tcp_congestion_ops *type);
+
+extern void tcp_init_congestion_control(struct tcp_sock *tp);
+extern void tcp_cleanup_congestion_control(struct tcp_sock *tp);
+extern int tcp_set_default_congestion_control(const char *name);
+extern void tcp_get_default_congestion_control(char *name);
+extern int tcp_set_congestion_control(struct tcp_sock *tp, const char *name);
+
+extern struct tcp_congestion_ops tcp_init_congestion_ops;
+extern u32 tcp_reno_ssthresh(struct tcp_sock *tp);
+extern void tcp_reno_cong_avoid(struct tcp_sock *tp, u32 ack,
+ u32 rtt, u32 in_flight, int flag);
+extern u32 tcp_reno_min_cwnd(struct tcp_sock *tp);
+extern struct tcp_congestion_ops tcp_reno;
+
+static inline void tcp_set_ca_state(struct tcp_sock *tp, u8 ca_state)
+{
+ if (tp->ca_ops->set_state)
+ tp->ca_ops->set_state(tp, ca_state);
+ tp->ca_state = ca_state;
+}
+
+static inline void tcp_ca_event(struct tcp_sock *tp, enum tcp_ca_event event)
+{
+ if (tp->ca_ops->cwnd_event)
+ tp->ca_ops->cwnd_event(tp, event);
+}
+
/* This determines how many packets are "in the network" to the best
* of our knowledge. In many cases it is conservative, but where
* detailed information is available from the receiver (via SACK
return (tp->packets_out - tp->left_out + tp->retrans_out);
}
-/*
- * Which congestion algorithim is in use on the connection.
- */
-#define tcp_is_vegas(__tp) ((__tp)->adv_cong == TCP_VEGAS)
-#define tcp_is_westwood(__tp) ((__tp)->adv_cong == TCP_WESTWOOD)
-#define tcp_is_bic(__tp) ((__tp)->adv_cong == TCP_BIC)
-
-/* Recalculate snd_ssthresh, we want to set it to:
- *
- * Reno:
- * one half the current congestion window, but no
- * less than two segments
- *
- * BIC:
- * behave like Reno until low_window is reached,
- * then increase congestion window slowly
- */
-static inline __u32 tcp_recalc_ssthresh(struct tcp_sock *tp)
-{
- if (tcp_is_bic(tp)) {
- if (sysctl_tcp_bic_fast_convergence &&
- tp->snd_cwnd < tp->bictcp.last_max_cwnd)
- tp->bictcp.last_max_cwnd = (tp->snd_cwnd *
- (BICTCP_BETA_SCALE
- + sysctl_tcp_bic_beta))
- / (2 * BICTCP_BETA_SCALE);
- else
- tp->bictcp.last_max_cwnd = tp->snd_cwnd;
-
- if (tp->snd_cwnd > sysctl_tcp_bic_low_window)
- return max((tp->snd_cwnd * sysctl_tcp_bic_beta)
- / BICTCP_BETA_SCALE, 2U);
- }
-
- return max(tp->snd_cwnd >> 1U, 2U);
-}
-
-/* Stop taking Vegas samples for now. */
-#define tcp_vegas_disable(__tp) ((__tp)->vegas.doing_vegas_now = 0)
-
-static inline void tcp_vegas_enable(struct tcp_sock *tp)
-{
- /* There are several situations when we must "re-start" Vegas:
- *
- * o when a connection is established
- * o after an RTO
- * o after fast recovery
- * o when we send a packet and there is no outstanding
- * unacknowledged data (restarting an idle connection)
- *
- * In these circumstances we cannot do a Vegas calculation at the
- * end of the first RTT, because any calculation we do is using
- * stale info -- both the saved cwnd and congestion feedback are
- * stale.
- *
- * Instead we must wait until the completion of an RTT during
- * which we actually receive ACKs.
- */
-
- /* Begin taking Vegas samples next time we send something. */
- tp->vegas.doing_vegas_now = 1;
-
- /* Set the beginning of the next send window. */
- tp->vegas.beg_snd_nxt = tp->snd_nxt;
-
- tp->vegas.cntRTT = 0;
- tp->vegas.minRTT = 0x7fffffff;
-}
-
-/* Should we be taking Vegas samples right now? */
-#define tcp_vegas_enabled(__tp) ((__tp)->vegas.doing_vegas_now)
-
-extern void tcp_ca_init(struct tcp_sock *tp);
-
-static inline void tcp_set_ca_state(struct tcp_sock *tp, u8 ca_state)
-{
- if (tcp_is_vegas(tp)) {
- if (ca_state == TCP_CA_Open)
- tcp_vegas_enable(tp);
- else
- tcp_vegas_disable(tp);
- }
- tp->ca_state = ca_state;
-}
-
/* If cwnd > ssthresh, we may raise ssthresh to be half-way to cwnd.
* The exception is rate halving phase, when cwnd is decreasing towards
* ssthresh.
static inline void __tcp_enter_cwr(struct tcp_sock *tp)
{
tp->undo_marker = 0;
- tp->snd_ssthresh = tcp_recalc_ssthresh(tp);
+ tp->snd_ssthresh = tp->ca_ops->ssthresh(tp);
tp->snd_cwnd = min(tp->snd_cwnd,
tcp_packets_in_flight(tp) + 1U);
tp->snd_cwnd_cnt = 0;
return 3;
}
-static __inline__ int tcp_minshall_check(const struct tcp_sock *tp)
-{
- return after(tp->snd_sml,tp->snd_una) &&
- !after(tp->snd_sml, tp->snd_nxt);
-}
-
static __inline__ void tcp_minshall_update(struct tcp_sock *tp, int mss,
const struct sk_buff *skb)
{
tp->snd_sml = TCP_SKB_CB(skb)->end_seq;
}
-/* Return 0, if packet can be sent now without violation Nagle's rules:
- 1. It is full sized.
- 2. Or it contains FIN.
- 3. Or TCP_NODELAY was set.
- 4. Or TCP_CORK is not set, and all sent packets are ACKed.
- With Minshall's modification: all sent small packets are ACKed.
- */
-
-static __inline__ int
-tcp_nagle_check(const struct tcp_sock *tp, const struct sk_buff *skb,
- unsigned mss_now, int nonagle)
-{
- return (skb->len < mss_now &&
- !(TCP_SKB_CB(skb)->flags & TCPCB_FLAG_FIN) &&
- ((nonagle&TCP_NAGLE_CORK) ||
- (!nonagle &&
- tp->packets_out &&
- tcp_minshall_check(tp))));
-}
-
-extern void tcp_set_skb_tso_segs(struct sock *, struct sk_buff *);
-
-/* This checks if the data bearing packet SKB (usually sk->sk_send_head)
- * should be put on the wire right now.
- */
-static __inline__ int tcp_snd_test(struct sock *sk,
- struct sk_buff *skb,
- unsigned cur_mss, int nonagle)
-{
- struct tcp_sock *tp = tcp_sk(sk);
- int pkts = tcp_skb_pcount(skb);
-
- if (!pkts) {
- tcp_set_skb_tso_segs(sk, skb);
- pkts = tcp_skb_pcount(skb);
- }
-
- /* RFC 1122 - section 4.2.3.4
- *
- * We must queue if
- *
- * a) The right edge of this frame exceeds the window
- * b) There are packets in flight and we have a small segment
- * [SWS avoidance and Nagle algorithm]
- * (part of SWS is done on packetization)
- * Minshall version sounds: there are no _small_
- * segments in flight. (tcp_nagle_check)
- * c) We have too many packets 'in flight'
- *
- * Don't use the nagle rule for urgent data (or
- * for the final FIN -DaveM).
- *
- * Also, Nagle rule does not apply to frames, which
- * sit in the middle of queue (they have no chances
- * to get new data) and if room at tail of skb is
- * not enough to save something seriously (<32 for now).
- */
-
- /* Don't be strict about the congestion window for the
- * final FIN frame. -DaveM
- */
- return (((nonagle&TCP_NAGLE_PUSH) || tp->urg_mode
- || !tcp_nagle_check(tp, skb, cur_mss, nonagle)) &&
- (((tcp_packets_in_flight(tp) + (pkts-1)) < tp->snd_cwnd) ||
- (TCP_SKB_CB(skb)->flags & TCPCB_FLAG_FIN)) &&
- !after(TCP_SKB_CB(skb)->end_seq, tp->snd_una + tp->snd_wnd));
-}
-
static __inline__ void tcp_check_probe_timer(struct sock *sk, struct tcp_sock *tp)
{
if (!tp->packets_out && !tp->pending)
tcp_reset_xmit_timer(sk, TCP_TIME_PROBE0, tp->rto);
}
-static __inline__ int tcp_skb_is_last(const struct sock *sk,
- const struct sk_buff *skb)
-{
- return skb->next == (struct sk_buff *)&sk->sk_write_queue;
-}
-
-/* Push out any pending frames which were held back due to
- * TCP_CORK or attempt at coalescing tiny packets.
- * The socket must be locked by the caller.
- */
-static __inline__ void __tcp_push_pending_frames(struct sock *sk,
- struct tcp_sock *tp,
- unsigned cur_mss,
- int nonagle)
-{
- struct sk_buff *skb = sk->sk_send_head;
-
- if (skb) {
- if (!tcp_skb_is_last(sk, skb))
- nonagle = TCP_NAGLE_PUSH;
- if (!tcp_snd_test(sk, skb, cur_mss, nonagle) ||
- tcp_write_xmit(sk, nonagle))
- tcp_check_probe_timer(sk, tp);
- }
- tcp_cwnd_validate(sk, tp);
-}
-
static __inline__ void tcp_push_pending_frames(struct sock *sk,
struct tcp_sock *tp)
{
__tcp_push_pending_frames(sk, tp, tcp_current_mss(sk, 1), tp->nonagle);
}
-static __inline__ int tcp_may_send_now(struct sock *sk, struct tcp_sock *tp)
-{
- struct sk_buff *skb = sk->sk_send_head;
-
- return (skb &&
- tcp_snd_test(sk, skb, tcp_current_mss(sk, 1),
- tcp_skb_is_last(sk, skb) ? TCP_NAGLE_PUSH : tp->nonagle));
-}
-
static __inline__ void tcp_init_wl(struct tcp_sock *tp, u32 ack, u32 seq)
{
tp->snd_wl1 = seq;
extern int tcp_proc_register(struct tcp_seq_afinfo *afinfo);
extern void tcp_proc_unregister(struct tcp_seq_afinfo *afinfo);
-/* TCP Westwood functions and constants */
-
-#define TCP_WESTWOOD_INIT_RTT (20*HZ) /* maybe too conservative?! */
-#define TCP_WESTWOOD_RTT_MIN (HZ/20) /* 50ms */
-
-static inline void tcp_westwood_update_rtt(struct tcp_sock *tp, __u32 rtt_seq)
-{
- if (tcp_is_westwood(tp))
- tp->westwood.rtt = rtt_seq;
-}
-
-static inline __u32 __tcp_westwood_bw_rttmin(const struct tcp_sock *tp)
-{
- return max((tp->westwood.bw_est) * (tp->westwood.rtt_min) /
- (__u32) (tp->mss_cache_std),
- 2U);
-}
-
-static inline __u32 tcp_westwood_bw_rttmin(const struct tcp_sock *tp)
-{
- return tcp_is_westwood(tp) ? __tcp_westwood_bw_rttmin(tp) : 0;
-}
-
-static inline int tcp_westwood_ssthresh(struct tcp_sock *tp)
-{
- __u32 ssthresh = 0;
-
- if (tcp_is_westwood(tp)) {
- ssthresh = __tcp_westwood_bw_rttmin(tp);
- if (ssthresh)
- tp->snd_ssthresh = ssthresh;
- }
-
- return (ssthresh != 0);
-}
-
-static inline int tcp_westwood_cwnd(struct tcp_sock *tp)
-{
- __u32 cwnd = 0;
-
- if (tcp_is_westwood(tp)) {
- cwnd = __tcp_westwood_bw_rttmin(tp);
- if (cwnd)
- tp->snd_cwnd = cwnd;
- }
-
- return (cwnd != 0);
-}
#endif /* _TCP_H */
git.openpandora.org / pandora-kernel.git / blobdiff