[TCP] TCP YEAH: Use vegas dont copy it.

Rather than using a copy of vegas code, the YEAH code should just have
it exported so there is common code.

Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 24 insertions, 29 deletions

diff --git a/net/ipv4/tcp_yeah.c b/net/ipv4/tcp_yeah.c
index 81ef02c1649a..545ed237ab53 100644
--- a/net/ipv4/tcp_yeah.c
+++ b/net/ipv4/tcp_yeah.c
@@ -6,13 +6,14 @@
  *    http://wil.cs.caltech.edu/pfldnet2007/paper/YeAH_TCP.pdf
  *
  */
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/skbuff.h>
+#include <linux/inet_diag.h>
 
-#include "tcp_yeah.h"
+#include <net/tcp.h>
 
-/* Default values of the Vegas variables, in fixed-point representation
- * with V_PARAM_SHIFT bits to the right of the binary point.
- */
-#define V_PARAM_SHIFT 1
+#include "tcp_vegas.h"
 
 #define TCP_YEAH_ALPHA       80 //lin number of packets queued at the bottleneck
 #define TCP_YEAH_GAMMA        1 //lin fraction of queue to be removed per rtt
@@ -26,14 +27,7 @@
 
 /* YeAH variables */
 struct yeah {
-        /* Vegas */
-        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) */
+        struct vegas vegas;     /* must be first */
 
         /* YeAH */
         u32 lastQ;
@@ -84,9 +78,10 @@ static void tcp_yeah_cong_avoid(struct sock *sk, u32 ack,
         if (!tcp_is_cwnd_limited(sk, in_flight))
                 return;
 
-        if (tp->snd_cwnd <= tp->snd_ssthresh) {
+        if (tp->snd_cwnd <= tp->snd_ssthresh)
                 tcp_slow_start(tp);
-        } else if (!yeah->doing_reno_now) {
+
+        else if (!yeah->doing_reno_now) {
                 /* Scalable */
 
                 tp->snd_cwnd_cnt+=yeah->pkts_acked;
@@ -110,19 +105,19 @@ static void tcp_yeah_cong_avoid(struct sock *sk, u32 ack,
                 }
         }
 
-        /* The key players are v_beg_snd_una and v_beg_snd_nxt.
+        /* The key players are v_vegas.beg_snd_una and v_beg_snd_nxt.
          *
          * These are so named because they represent the approximate values
          * of snd_una and snd_nxt at the beginning of the current RTT. More
          * precisely, they represent the amount of data sent during the RTT.
          * At the end of the RTT, when we receive an ACK for v_beg_snd_nxt,
-         * we will calculate that (v_beg_snd_nxt - v_beg_snd_una) outstanding
+         * we will calculate that (v_beg_snd_nxt - v_vegas.beg_snd_una) outstanding
          * bytes of data have been ACKed during the course of the RTT, giving
          * an "actual" rate of:
          *
-         *     (v_beg_snd_nxt - v_beg_snd_una) / (rtt duration)
+         *     (v_beg_snd_nxt - v_vegas.beg_snd_una) / (rtt duration)
          *
-         * Unfortunately, v_beg_snd_una is not exactly equal to snd_una,
+         * Unfortunately, v_vegas.beg_snd_una is not exactly equal to snd_una,
          * because delayed ACKs can cover more than one segment, so they
          * don't line up yeahly with the boundaries of RTTs.
          *
@@ -132,7 +127,7 @@ static void tcp_yeah_cong_avoid(struct sock *sk, u32 ack,
          * So we keep track of our cwnd separately, in v_beg_snd_cwnd.
          */
 
-        if (after(ack, yeah->beg_snd_nxt)) {
+        if (after(ack, yeah->vegas.beg_snd_nxt)) {
 
                 /* We do the Vegas calculations only if we got enough RTT
                  * samples that we can be reasonably sure that we got
@@ -143,7 +138,7 @@ static void tcp_yeah_cong_avoid(struct sock *sk, u32 ack,
                  * If  we have 3 samples, we should be OK.
                  */
 
-                if (yeah->cntRTT > 2) {
+                if (yeah->vegas.cntRTT > 2) {
                         u32 rtt, queue;
                         u64 bw;
 
@@ -158,18 +153,18 @@ static void tcp_yeah_cong_avoid(struct sock *sk, u32 ack,
                          * of delayed ACKs, at the cost of noticing congestion
                          * a bit later.
                          */
-                        rtt = yeah->minRTT;
+                        rtt = yeah->vegas.minRTT;
 
                         /* Compute excess number of packets above bandwidth
                          * Avoid doing full 64 bit divide.
                          */
                         bw = tp->snd_cwnd;
-                        bw *= rtt - yeah->baseRTT;
+                        bw *= rtt - yeah->vegas.baseRTT;
                         do_div(bw, rtt);
                         queue = bw;
 
                         if (queue > TCP_YEAH_ALPHA ||
-                            rtt - yeah->baseRTT > (yeah->baseRTT / TCP_YEAH_PHY)) {
+                            rtt - yeah->vegas.baseRTT > (yeah->vegas.baseRTT / TCP_YEAH_PHY)) {
                                 if (queue > TCP_YEAH_ALPHA
                                     && tp->snd_cwnd > yeah->reno_count) {
                                         u32 reduction = min(queue / TCP_YEAH_GAMMA ,
@@ -208,13 +203,13 @@ static void tcp_yeah_cong_avoid(struct sock *sk, u32 ack,
                 /* Save the extent of the current window so we can use this
                  * at the end of the next RTT.
                  */
-                yeah->beg_snd_una  = yeah->beg_snd_nxt;
-                yeah->beg_snd_nxt  = tp->snd_nxt;
-                yeah->beg_snd_cwnd = tp->snd_cwnd;
+                yeah->vegas.beg_snd_una  = yeah->vegas.beg_snd_nxt;
+                yeah->vegas.beg_snd_nxt  = tp->snd_nxt;
+                yeah->vegas.beg_snd_cwnd = tp->snd_cwnd;
 
                 /* Wipe the slate clean for the next RTT. */
-                yeah->cntRTT = 0;
-                yeah->minRTT = 0x7fffffff;
+                yeah->vegas.cntRTT = 0;
+                yeah->vegas.minRTT = 0x7fffffff;
         }
 }