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Diffstat (limited to 'net/ipv4/tcp_yeah.c')
-rw-r--r--net/ipv4/tcp_yeah.c42
1 files changed, 23 insertions, 19 deletions
diff --git a/net/ipv4/tcp_yeah.c b/net/ipv4/tcp_yeah.c
index 18355a2608e1..46dd1bee583a 100644
--- a/net/ipv4/tcp_yeah.c
+++ b/net/ipv4/tcp_yeah.c
@@ -74,7 +74,7 @@ static void tcp_yeah_pkts_acked(struct sock *sk, u32 pkts_acked)
74} 74}
75 75
76static void tcp_yeah_cong_avoid(struct sock *sk, u32 ack, 76static void tcp_yeah_cong_avoid(struct sock *sk, u32 ack,
77 u32 seq_rtt, u32 in_flight, int flag) 77 u32 seq_rtt, u32 in_flight, int flag)
78{ 78{
79 struct tcp_sock *tp = tcp_sk(sk); 79 struct tcp_sock *tp = tcp_sk(sk);
80 struct yeah *yeah = inet_csk_ca(sk); 80 struct yeah *yeah = inet_csk_ca(sk);
@@ -142,8 +142,8 @@ static void tcp_yeah_cong_avoid(struct sock *sk, u32 ack,
142 */ 142 */
143 143
144 if (yeah->cntRTT > 2) { 144 if (yeah->cntRTT > 2) {
145 u32 rtt; 145 u32 rtt, queue;
146 u32 queue, maxqueue; 146 u64 bw;
147 147
148 /* We have enough RTT samples, so, using the Vegas 148 /* We have enough RTT samples, so, using the Vegas
149 * algorithm, we determine if we should increase or 149 * algorithm, we determine if we should increase or
@@ -158,32 +158,36 @@ static void tcp_yeah_cong_avoid(struct sock *sk, u32 ack,
158 */ 158 */
159 rtt = yeah->minRTT; 159 rtt = yeah->minRTT;
160 160
161 queue = (u32)div64_64((u64)tp->snd_cwnd * (rtt - yeah->baseRTT), rtt); 161 /* Compute excess number of packets above bandwidth
162 162 * Avoid doing full 64 bit divide.
163 maxqueue = TCP_YEAH_ALPHA; 163 */
164 164 bw = tp->snd_cwnd;
165 if (queue > maxqueue || 165 bw *= rtt - yeah->baseRTT;
166 rtt - yeah->baseRTT > (yeah->baseRTT / TCP_YEAH_PHY)) { 166 do_div(bw, rtt);
167 167 queue = bw;
168 if (queue > maxqueue && tp->snd_cwnd > yeah->reno_count) { 168
169 u32 reduction = min( queue / TCP_YEAH_GAMMA , 169 if (queue > TCP_YEAH_ALPHA ||
170 tp->snd_cwnd >> TCP_YEAH_EPSILON ); 170 rtt - yeah->baseRTT > (yeah->baseRTT / TCP_YEAH_PHY)) {
171 if (queue > TCP_YEAH_ALPHA
172 && tp->snd_cwnd > yeah->reno_count) {
173 u32 reduction = min(queue / TCP_YEAH_GAMMA ,
174 tp->snd_cwnd >> TCP_YEAH_EPSILON);
171 175
172 tp->snd_cwnd -= reduction; 176 tp->snd_cwnd -= reduction;
173 177
174 tp->snd_cwnd = max( tp->snd_cwnd, yeah->reno_count); 178 tp->snd_cwnd = max(tp->snd_cwnd,
179 yeah->reno_count);
175 180
176 tp->snd_ssthresh = tp->snd_cwnd; 181 tp->snd_ssthresh = tp->snd_cwnd;
177 } 182 }
178 183
179 if (yeah->reno_count <= 2) 184 if (yeah->reno_count <= 2)
180 yeah->reno_count = max( tp->snd_cwnd>>1, 2U); 185 yeah->reno_count = max(tp->snd_cwnd>>1, 2U);
181 else 186 else
182 yeah->reno_count++; 187 yeah->reno_count++;
183 188
184 yeah->doing_reno_now = 189 yeah->doing_reno_now = min(yeah->doing_reno_now + 1,
185 min_t( u32, yeah->doing_reno_now + 1 , 0xffffff); 190 0xffffffU);
186
187 } else { 191 } else {
188 yeah->fast_count++; 192 yeah->fast_count++;
189 193