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Diffstat (limited to 'net/ipv4/tcp_cong.c')
-rw-r--r--net/ipv4/tcp_cong.c55
1 files changed, 24 insertions, 31 deletions
diff --git a/net/ipv4/tcp_cong.c b/net/ipv4/tcp_cong.c
index 7b09d8b49fa5..b1c5970d47a1 100644
--- a/net/ipv4/tcp_cong.c
+++ b/net/ipv4/tcp_cong.c
@@ -74,24 +74,34 @@ void tcp_unregister_congestion_control(struct tcp_congestion_ops *ca)
EXPORT_SYMBOL_GPL(tcp_unregister_congestion_control);
/* Assign choice of congestion control. */
-void tcp_init_congestion_control(struct sock *sk)
+void tcp_assign_congestion_control(struct sock *sk)
{
struct inet_connection_sock *icsk = inet_csk(sk);
struct tcp_congestion_ops *ca;
- /* if no choice made yet assign the current value set as default */
- if (icsk->icsk_ca_ops == &tcp_init_congestion_ops) {
- rcu_read_lock();
- list_for_each_entry_rcu(ca, &tcp_cong_list, list) {
- if (try_module_get(ca->owner)) {
- icsk->icsk_ca_ops = ca;
- break;
- }
-
- /* fallback to next available */
+ rcu_read_lock();
+ list_for_each_entry_rcu(ca, &tcp_cong_list, list) {
+ if (likely(try_module_get(ca->owner))) {
+ icsk->icsk_ca_ops = ca;
+ goto out;
}
- rcu_read_unlock();
+ /* Fallback to next available. The last really
+ * guaranteed fallback is Reno from this list.
+ */
}
+out:
+ rcu_read_unlock();
+
+ /* Clear out private data before diag gets it and
+ * the ca has not been initialized.
+ */
+ if (ca->get_info)
+ memset(icsk->icsk_ca_priv, 0, sizeof(icsk->icsk_ca_priv));
+}
+
+void tcp_init_congestion_control(struct sock *sk)
+{
+ const struct inet_connection_sock *icsk = inet_csk(sk);
if (icsk->icsk_ca_ops->init)
icsk->icsk_ca_ops->init(sk);
@@ -142,7 +152,6 @@ static int __init tcp_congestion_default(void)
}
late_initcall(tcp_congestion_default);
-
/* Build string with list of available congestion control values */
void tcp_get_available_congestion_control(char *buf, size_t maxlen)
{
@@ -154,7 +163,6 @@ void tcp_get_available_congestion_control(char *buf, size_t maxlen)
offs += snprintf(buf + offs, maxlen - offs,
"%s%s",
offs == 0 ? "" : " ", ca->name);
-
}
rcu_read_unlock();
}
@@ -186,7 +194,6 @@ void tcp_get_allowed_congestion_control(char *buf, size_t maxlen)
offs += snprintf(buf + offs, maxlen - offs,
"%s%s",
offs == 0 ? "" : " ", ca->name);
-
}
rcu_read_unlock();
}
@@ -230,7 +237,6 @@ out:
return ret;
}
-
/* Change congestion control for socket */
int tcp_set_congestion_control(struct sock *sk, const char *name)
{
@@ -285,15 +291,13 @@ int tcp_set_congestion_control(struct sock *sk, const char *name)
* ABC caps N to 2. Slow start exits when cwnd grows over ssthresh and
* returns the leftover acks to adjust cwnd in congestion avoidance mode.
*/
-int tcp_slow_start(struct tcp_sock *tp, u32 acked)
+void tcp_slow_start(struct tcp_sock *tp, u32 acked)
{
u32 cwnd = tp->snd_cwnd + acked;
if (cwnd > tp->snd_ssthresh)
cwnd = tp->snd_ssthresh + 1;
- acked -= cwnd - tp->snd_cwnd;
tp->snd_cwnd = min(cwnd, tp->snd_cwnd_clamp);
- return acked;
}
EXPORT_SYMBOL_GPL(tcp_slow_start);
@@ -337,6 +341,7 @@ EXPORT_SYMBOL_GPL(tcp_reno_cong_avoid);
u32 tcp_reno_ssthresh(struct sock *sk)
{
const struct tcp_sock *tp = tcp_sk(sk);
+
return max(tp->snd_cwnd >> 1U, 2U);
}
EXPORT_SYMBOL_GPL(tcp_reno_ssthresh);
@@ -348,15 +353,3 @@ struct tcp_congestion_ops tcp_reno = {
.ssthresh = tcp_reno_ssthresh,
.cong_avoid = tcp_reno_cong_avoid,
};
-
-/* Initial congestion control used (until SYN)
- * really reno under another name so we can tell difference
- * during tcp_set_default_congestion_control
- */
-struct tcp_congestion_ops tcp_init_congestion_ops = {
- .name = "",
- .owner = THIS_MODULE,
- .ssthresh = tcp_reno_ssthresh,
- .cong_avoid = tcp_reno_cong_avoid,
-};
-EXPORT_SYMBOL_GPL(tcp_init_congestion_ops);