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Diffstat (limited to 'net/ipv4/tcp_yeah.c')
-rw-r--r--net/ipv4/tcp_yeah.c99
1 files changed, 39 insertions, 60 deletions
diff --git a/net/ipv4/tcp_yeah.c b/net/ipv4/tcp_yeah.c
index 05c3b6f0e8e1..18b07ff5d20e 100644
--- a/net/ipv4/tcp_yeah.c
+++ b/net/ipv4/tcp_yeah.c
@@ -1,9 +1,10 @@
+// SPDX-License-Identifier: GPL-2.0-only
/*
*
* YeAH TCP
*
* For further details look at:
- * http://wil.cs.caltech.edu/pfldnet2007/paper/YeAH_TCP.pdf
+ * https://web.archive.org/web/20080316215752/http://wil.cs.caltech.edu/pfldnet2007/paper/YeAH_TCP.pdf
*
*/
#include <linux/mm.h>
@@ -15,13 +16,13 @@
#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
-#define TCP_YEAH_DELTA 3 //log minimum fraction of cwnd to be removed on loss
-#define TCP_YEAH_EPSILON 1 //log maximum fraction to be removed on early decongestion
-#define TCP_YEAH_PHY 8 //lin maximum delta from base
-#define TCP_YEAH_RHO 16 //lin minimum number of consecutive rtt to consider competition on loss
-#define TCP_YEAH_ZETA 50 //lin minimum number of state switchs to reset reno_count
+#define TCP_YEAH_ALPHA 80 /* number of packets queued at the bottleneck */
+#define TCP_YEAH_GAMMA 1 /* fraction of queue to be removed per rtt */
+#define TCP_YEAH_DELTA 3 /* log minimum fraction of cwnd to be removed on loss */
+#define TCP_YEAH_EPSILON 1 /* log maximum fraction to be removed on early decongestion */
+#define TCP_YEAH_PHY 8 /* maximum delta from base */
+#define TCP_YEAH_RHO 16 /* minimum number of consecutive rtt to consider competition on loss */
+#define TCP_YEAH_ZETA 50 /* minimum number of state switches to reset reno_count */
#define TCP_SCALABLE_AI_CNT 100U
@@ -35,8 +36,6 @@ struct yeah {
u32 reno_count;
u32 fast_count;
-
- u32 pkts_acked;
};
static void tcp_yeah_init(struct sock *sk)
@@ -54,47 +53,29 @@ static void tcp_yeah_init(struct sock *sk)
/* Ensure the MD arithmetic works. This is somewhat pedantic,
* since I don't think we will see a cwnd this large. :) */
tp->snd_cwnd_clamp = min_t(u32, tp->snd_cwnd_clamp, 0xffffffff/128);
-
-}
-
-
-static void tcp_yeah_pkts_acked(struct sock *sk, u32 pkts_acked, s32 rtt_us)
-{
- const struct inet_connection_sock *icsk = inet_csk(sk);
- struct yeah *yeah = inet_csk_ca(sk);
-
- if (icsk->icsk_ca_state == TCP_CA_Open)
- yeah->pkts_acked = pkts_acked;
-
- tcp_vegas_pkts_acked(sk, pkts_acked, rtt_us);
}
-static void tcp_yeah_cong_avoid(struct sock *sk, u32 ack, u32 in_flight)
+static void tcp_yeah_cong_avoid(struct sock *sk, u32 ack, u32 acked)
{
struct tcp_sock *tp = tcp_sk(sk);
struct yeah *yeah = inet_csk_ca(sk);
- if (!tcp_is_cwnd_limited(sk, in_flight))
+ if (!tcp_is_cwnd_limited(sk))
return;
- if (tp->snd_cwnd <= tp->snd_ssthresh)
- tcp_slow_start(tp);
+ if (tcp_in_slow_start(tp)) {
+ acked = tcp_slow_start(tp, acked);
+ if (!acked)
+ goto do_vegas;
+ }
- else if (!yeah->doing_reno_now) {
+ if (!yeah->doing_reno_now) {
/* Scalable */
-
- tp->snd_cwnd_cnt += yeah->pkts_acked;
- if (tp->snd_cwnd_cnt > min(tp->snd_cwnd, TCP_SCALABLE_AI_CNT)){
- if (tp->snd_cwnd < tp->snd_cwnd_clamp)
- tp->snd_cwnd++;
- tp->snd_cwnd_cnt = 0;
- }
-
- yeah->pkts_acked = 1;
-
+ tcp_cong_avoid_ai(tp, min(tcp_snd_cwnd(tp), TCP_SCALABLE_AI_CNT),
+ acked);
} else {
/* Reno */
- tcp_cong_avoid_ai(tp, tp->snd_cwnd);
+ tcp_cong_avoid_ai(tp, tcp_snd_cwnd(tp), acked);
}
/* The key players are v_vegas.beg_snd_una and v_beg_snd_nxt.
@@ -118,9 +99,8 @@ static void tcp_yeah_cong_avoid(struct sock *sk, u32 ack, u32 in_flight)
* of bytes we send in an RTT is often less than our cwnd will allow.
* So we keep track of our cwnd separately, in v_beg_snd_cwnd.
*/
-
+do_vegas:
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
* at least one RTT sample that wasn't from a delayed ACK.
@@ -150,7 +130,7 @@ static void tcp_yeah_cong_avoid(struct sock *sk, u32 ack, u32 in_flight)
/* Compute excess number of packets above bandwidth
* Avoid doing full 64 bit divide.
*/
- bw = tp->snd_cwnd;
+ bw = tcp_snd_cwnd(tp);
bw *= rtt - yeah->vegas.baseRTT;
do_div(bw, rtt);
queue = bw;
@@ -158,20 +138,20 @@ static void tcp_yeah_cong_avoid(struct sock *sk, u32 ack, u32 in_flight)
if (queue > TCP_YEAH_ALPHA ||
rtt - yeah->vegas.baseRTT > (yeah->vegas.baseRTT / TCP_YEAH_PHY)) {
if (queue > TCP_YEAH_ALPHA &&
- tp->snd_cwnd > yeah->reno_count) {
+ tcp_snd_cwnd(tp) > yeah->reno_count) {
u32 reduction = min(queue / TCP_YEAH_GAMMA ,
- tp->snd_cwnd >> TCP_YEAH_EPSILON);
+ tcp_snd_cwnd(tp) >> TCP_YEAH_EPSILON);
- tp->snd_cwnd -= reduction;
+ tcp_snd_cwnd_set(tp, tcp_snd_cwnd(tp) - reduction);
- tp->snd_cwnd = max(tp->snd_cwnd,
- yeah->reno_count);
+ tcp_snd_cwnd_set(tp, max(tcp_snd_cwnd(tp),
+ yeah->reno_count));
- tp->snd_ssthresh = tp->snd_cwnd;
+ tp->snd_ssthresh = tcp_snd_cwnd(tp);
}
if (yeah->reno_count <= 2)
- yeah->reno_count = max(tp->snd_cwnd>>1, 2U);
+ yeah->reno_count = max(tcp_snd_cwnd(tp)>>1, 2U);
else
yeah->reno_count++;
@@ -189,7 +169,6 @@ static void tcp_yeah_cong_avoid(struct sock *sk, u32 ack, u32 in_flight)
}
yeah->lastQ = queue;
-
}
/* Save the extent of the current window so we can use this
@@ -197,7 +176,7 @@ static void tcp_yeah_cong_avoid(struct sock *sk, u32 ack, u32 in_flight)
*/
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;
+ yeah->vegas.beg_snd_cwnd = tcp_snd_cwnd(tp);
/* Wipe the slate clean for the next RTT. */
yeah->vegas.cntRTT = 0;
@@ -205,7 +184,8 @@ static void tcp_yeah_cong_avoid(struct sock *sk, u32 ack, u32 in_flight)
}
}
-static u32 tcp_yeah_ssthresh(struct sock *sk) {
+static u32 tcp_yeah_ssthresh(struct sock *sk)
+{
const struct tcp_sock *tp = tcp_sk(sk);
struct yeah *yeah = inet_csk_ca(sk);
u32 reduction;
@@ -213,28 +193,27 @@ static u32 tcp_yeah_ssthresh(struct sock *sk) {
if (yeah->doing_reno_now < TCP_YEAH_RHO) {
reduction = yeah->lastQ;
- reduction = min( reduction, max(tp->snd_cwnd>>1, 2U) );
+ reduction = min(reduction, max(tcp_snd_cwnd(tp)>>1, 2U));
- reduction = max( reduction, tp->snd_cwnd >> TCP_YEAH_DELTA);
+ reduction = max(reduction, tcp_snd_cwnd(tp) >> TCP_YEAH_DELTA);
} else
- reduction = max(tp->snd_cwnd>>1, 2U);
+ reduction = max(tcp_snd_cwnd(tp)>>1, 2U);
yeah->fast_count = 0;
yeah->reno_count = max(yeah->reno_count>>1, 2U);
- return tp->snd_cwnd - reduction;
+ return max_t(int, tcp_snd_cwnd(tp) - reduction, 2);
}
static struct tcp_congestion_ops tcp_yeah __read_mostly = {
- .flags = TCP_CONG_RTT_STAMP,
.init = tcp_yeah_init,
.ssthresh = tcp_yeah_ssthresh,
+ .undo_cwnd = tcp_reno_undo_cwnd,
.cong_avoid = tcp_yeah_cong_avoid,
- .min_cwnd = tcp_reno_min_cwnd,
.set_state = tcp_vegas_state,
.cwnd_event = tcp_vegas_cwnd_event,
.get_info = tcp_vegas_get_info,
- .pkts_acked = tcp_yeah_pkts_acked,
+ .pkts_acked = tcp_vegas_pkts_acked,
.owner = THIS_MODULE,
.name = "yeah",
@@ -242,7 +221,7 @@ static struct tcp_congestion_ops tcp_yeah __read_mostly = {
static int __init tcp_yeah_register(void)
{
- BUG_ON(sizeof(struct yeah) > ICSK_CA_PRIV_SIZE);
+ BUILD_BUG_ON(sizeof(struct yeah) > ICSK_CA_PRIV_SIZE);
tcp_register_congestion_control(&tcp_yeah);
return 0;
}
generated by cgit (git 2.34.1) at 2025-12-21 22:51:01 +0000