[TCP]: Add pluggable congestion control algorithm infrastructure.
Allow TCP to have multiple pluggable congestion control algorithms.
Algorithms are defined by a set of operations and can be built in
or modules. The legacy "new RENO" algorithm is used as a starting
point and fallback.
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/sysctl.h b/include/linux/sysctl.h
index 614e939..72965bf 100644
--- a/include/linux/sysctl.h
+++ b/include/linux/sysctl.h
@@ -333,21 +333,14 @@
NET_TCP_FRTO=92,
NET_TCP_LOW_LATENCY=93,
NET_IPV4_IPFRAG_SECRET_INTERVAL=94,
- NET_TCP_WESTWOOD=95,
NET_IPV4_IGMP_MAX_MSF=96,
NET_TCP_NO_METRICS_SAVE=97,
- NET_TCP_VEGAS=98,
- NET_TCP_VEGAS_ALPHA=99,
- NET_TCP_VEGAS_BETA=100,
- NET_TCP_VEGAS_GAMMA=101,
- NET_TCP_BIC=102,
- NET_TCP_BIC_FAST_CONVERGENCE=103,
- NET_TCP_BIC_LOW_WINDOW=104,
NET_TCP_DEFAULT_WIN_SCALE=105,
NET_TCP_MODERATE_RCVBUF=106,
NET_TCP_TSO_WIN_DIVISOR=107,
NET_TCP_BIC_BETA=108,
NET_IPV4_ICMP_ERRORS_USE_INBOUND_IFADDR=109,
+ NET_TCP_CONG_CONTROL=110,
};
enum {
diff --git a/include/linux/tcp.h b/include/linux/tcp.h
index 97a7c9e..3ea75dd 100644
--- a/include/linux/tcp.h
+++ b/include/linux/tcp.h
@@ -203,13 +203,6 @@
__u32 end_seq;
};
-enum tcp_congestion_algo {
- TCP_RENO=0,
- TCP_VEGAS,
- TCP_WESTWOOD,
- TCP_BIC,
-};
-
struct tcp_options_received {
/* PAWS/RTTM data */
long ts_recent_stamp;/* Time we stored ts_recent (for aging) */
@@ -305,7 +298,7 @@
__u8 reordering; /* Packet reordering metric. */
__u8 frto_counter; /* Number of new acks after RTO */
- __u8 adv_cong; /* Using Vegas, Westwood, or BIC */
+ __u8 unused;
__u8 defer_accept; /* User waits for some data after accept() */
/* RTT measurement */
@@ -401,37 +394,10 @@
__u32 time;
} rcvq_space;
-/* TCP Westwood structure */
- struct {
- __u32 bw_ns_est; /* first bandwidth estimation..not too smoothed 8) */
- __u32 bw_est; /* bandwidth estimate */
- __u32 rtt_win_sx; /* here starts a new evaluation... */
- __u32 bk;
- __u32 snd_una; /* used for evaluating the number of acked bytes */
- __u32 cumul_ack;
- __u32 accounted;
- __u32 rtt;
- __u32 rtt_min; /* minimum observed RTT */
- } westwood;
-
-/* Vegas variables */
- struct {
- __u32 beg_snd_nxt; /* right edge during last RTT */
- __u32 beg_snd_una; /* left edge during last RTT */
- __u32 beg_snd_cwnd; /* saves the size of the cwnd */
- __u8 doing_vegas_now;/* if true, do vegas for this RTT */
- __u16 cntRTT; /* # of RTTs measured within last RTT */
- __u32 minRTT; /* min of RTTs measured within last RTT (in usec) */
- __u32 baseRTT; /* the min of all Vegas RTT measurements seen (in usec) */
- } vegas;
-
- /* BI TCP Parameters */
- struct {
- __u32 cnt; /* increase cwnd by 1 after this number of ACKs */
- __u32 last_max_cwnd; /* last maximium snd_cwnd */
- __u32 last_cwnd; /* the last snd_cwnd */
- __u32 last_stamp; /* time when updated last_cwnd */
- } bictcp;
+ /* Pluggable TCP congestion control hook */
+ struct tcp_congestion_ops *ca_ops;
+ u32 ca_priv[16];
+#define TCP_CA_PRIV_SIZE (16*sizeof(u32))
};
static inline struct tcp_sock *tcp_sk(const struct sock *sk)
@@ -439,6 +405,11 @@
return (struct tcp_sock *)sk;
}
+static inline void *tcp_ca(const struct tcp_sock *tp)
+{
+ return (void *) tp->ca_priv;
+}
+
#endif
#endif /* _LINUX_TCP_H */