[PATCH] Report vegas connection info

[Stephen Hemminger <shemminger@xxxxxxxx>]

Simple extension of tcp_diag to send out vegas information.
Have simple addition to 'ss' command to print:

$ ss -i
State      Recv-Q Send-Q      Local Address:Port          Peer Address:Port
ESTAB      0      0             172.20.1.73:32775          172.20.1.60:iperf  
        rto:201 rtt:1.875/0.75 cwnd:8 ssthresh:3 vegas bw:9.2672e+10

diff -Nru a/include/linux/tcp_diag.h b/include/linux/tcp_diag.h
--- a/include/linux/tcp_diag.h  Fri Apr 23 14:56:53 2004
+++ b/include/linux/tcp_diag.h  Fri Apr 23 14:56:53 2004
@@ -98,9 +98,10 @@
        TCPDIAG_NONE,
        TCPDIAG_MEMINFO,
        TCPDIAG_INFO,
+       TCPDIAG_VEGASINFO,
 };
 
-#define TCPDIAG_MAX TCPDIAG_INFO
+#define TCPDIAG_MAX TCPDIAG_VEGASINFO
 
 
 /* TCPDIAG_MEM */
@@ -112,5 +113,15 @@
        __u32   tcpdiag_fmem;
        __u32   tcpdiag_tmem;
 };
+
+/* TCPDIAG_VEGASINFO */
+
+struct tcpvegas_info {
+       __u32   tcpv_enabled;
+       __u32   tcpv_rttcnt;
+       __u32   tcpv_rtt;
+       __u32   tcpv_minrtt;
+};
+
 
 #endif /* _TCP_DIAG_H_ */
diff -Nru a/net/ipv4/tcp_diag.c b/net/ipv4/tcp_diag.c
--- a/net/ipv4/tcp_diag.c       Fri Apr 23 14:56:53 2004
+++ b/net/ipv4/tcp_diag.c       Fri Apr 23 14:56:53 2004
@@ -50,6 +50,7 @@
        struct nlmsghdr  *nlh;
        struct tcp_info  *info = NULL;
        struct tcpdiag_meminfo  *minfo = NULL;
+       struct tcpvegas_info *vinfo = NULL;
        unsigned char    *b = skb->tail;
 
        nlh = NLMSG_PUT(skb, pid, seq, TCPDIAG_GETSOCK, sizeof(*r));
@@ -59,6 +60,9 @@
                        minfo = TCPDIAG_PUT(skb, TCPDIAG_MEMINFO, 
sizeof(*minfo));
                if (ext & (1<<(TCPDIAG_INFO-1)))
                        info = TCPDIAG_PUT(skb, TCPDIAG_INFO, sizeof(*info));
+               
+               if (tcp_is_vegas(tp) && (ext & (1<<(TCPDIAG_VEGASINFO-1))))
+                       vinfo = TCPDIAG_PUT(skb, TCPDIAG_VEGASINFO, 
sizeof(*vinfo));
        }
        r->tcpdiag_family = sk->sk_family;
        r->tcpdiag_state = sk->sk_state;
@@ -194,6 +198,13 @@
                info->tcpi_snd_cwnd = tp->snd_cwnd;
                info->tcpi_advmss = tp->advmss;
                info->tcpi_reordering = tp->reordering;
+       }
+
+       if (vinfo) {
+               vinfo->tcpv_enabled = tp->vegas.doing_vegas_now;
+               vinfo->tcpv_rttcnt = tp->vegas.cntRTT;
+               vinfo->tcpv_rtt = tp->vegas.baseRTT;
+               vinfo->tcpv_minrtt = tp->vegas.minRTT;
        }
 
        nlh->nlmsg_len = skb->tail - b;