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authorDavid S. Miller <davem@davemloft.net>2012-07-10 03:14:24 -0700
committerDavid S. Miller <davem@davemloft.net>2012-07-10 22:40:08 -0700
commit81166dd6fa8eb780b2132d32fbc77eb6ac04e44e (patch)
tree7a41b12950640648d3bb95ca74bfa1391efa0421 /net/ipv4/tcp_metrics.c
parent94334d5ed4b64ebcd2c4b421e133b921f8ccf75d (diff)
downloadlinux-stericsson-81166dd6fa8eb780b2132d32fbc77eb6ac04e44e.tar.gz
tcp: Move timestamps from inetpeer to metrics cache.
With help from Lin Ming. Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4/tcp_metrics.c')
-rw-r--r--net/ipv4/tcp_metrics.c136
1 files changed, 131 insertions, 5 deletions
diff --git a/net/ipv4/tcp_metrics.c b/net/ipv4/tcp_metrics.c
index 56223bab251b..1fd83d3118fe 100644
--- a/net/ipv4/tcp_metrics.c
+++ b/net/ipv4/tcp_metrics.c
@@ -34,6 +34,8 @@ struct tcp_metrics_block {
struct tcp_metrics_block __rcu *tcpm_next;
struct inetpeer_addr tcpm_addr;
unsigned long tcpm_stamp;
+ u32 tcpm_ts;
+ u32 tcpm_ts_stamp;
u32 tcpm_lock;
u32 tcpm_vals[TCP_METRIC_MAX];
};
@@ -114,6 +116,8 @@ static void tcpm_suck_dst(struct tcp_metrics_block *tm, struct dst_entry *dst)
tm->tcpm_vals[TCP_METRIC_SSTHRESH] = dst_metric_raw(dst, RTAX_SSTHRESH);
tm->tcpm_vals[TCP_METRIC_CWND] = dst_metric_raw(dst, RTAX_CWND);
tm->tcpm_vals[TCP_METRIC_REORDERING] = dst_metric_raw(dst, RTAX_REORDERING);
+ tm->tcpm_ts = 0;
+ tm->tcpm_ts_stamp = 0;
}
static struct tcp_metrics_block *tcpm_new(struct dst_entry *dst,
@@ -230,6 +234,45 @@ static struct tcp_metrics_block *__tcp_get_metrics_req(struct request_sock *req,
return tm;
}
+static struct tcp_metrics_block *__tcp_get_metrics_tw(struct inet_timewait_sock *tw)
+{
+ struct inet6_timewait_sock *tw6;
+ struct tcp_metrics_block *tm;
+ struct inetpeer_addr addr;
+ unsigned int hash;
+ struct net *net;
+
+ addr.family = tw->tw_family;
+ switch (addr.family) {
+ case AF_INET:
+ addr.addr.a4 = tw->tw_daddr;
+ hash = (__force unsigned int) addr.addr.a4;
+ break;
+ case AF_INET6:
+ tw6 = inet6_twsk((struct sock *)tw);
+ *(struct in6_addr *)addr.addr.a6 = tw6->tw_v6_daddr;
+ hash = ((__force unsigned int) addr.addr.a6[0] ^
+ (__force unsigned int) addr.addr.a6[1] ^
+ (__force unsigned int) addr.addr.a6[2] ^
+ (__force unsigned int) addr.addr.a6[3]);
+ break;
+ default:
+ return NULL;
+ }
+
+ hash ^= (hash >> 24) ^ (hash >> 16) ^ (hash >> 8);
+
+ net = twsk_net(tw);
+ hash &= net->ipv4.tcp_metrics_hash_mask;
+
+ for (tm = rcu_dereference(net->ipv4.tcp_metrics_hash[hash].chain); tm;
+ tm = rcu_dereference(tm->tcpm_next)) {
+ if (addr_same(&tm->tcpm_addr, &addr))
+ break;
+ }
+ return tm;
+}
+
static struct tcp_metrics_block *tcp_get_metrics(struct sock *sk,
struct dst_entry *dst,
bool create)
@@ -496,7 +539,7 @@ reset:
tp->snd_cwnd_stamp = tcp_time_stamp;
}
-bool tcp_peer_is_proven(struct request_sock *req, struct dst_entry *dst)
+bool tcp_peer_is_proven(struct request_sock *req, struct dst_entry *dst, bool paws_check)
{
struct tcp_metrics_block *tm;
bool ret;
@@ -506,16 +549,99 @@ bool tcp_peer_is_proven(struct request_sock *req, struct dst_entry *dst)
rcu_read_lock();
tm = __tcp_get_metrics_req(req, dst);
- if (tm && tcp_metric_get(tm, TCP_METRIC_RTT))
- ret = true;
- else
- ret = false;
+ if (paws_check) {
+ if (tm &&
+ (u32)get_seconds() - tm->tcpm_ts_stamp < TCP_PAWS_MSL &&
+ (s32)(tm->tcpm_ts - req->ts_recent) > TCP_PAWS_WINDOW)
+ ret = false;
+ else
+ ret = true;
+ } else {
+ if (tm && tcp_metric_get(tm, TCP_METRIC_RTT) && tm->tcpm_ts_stamp)
+ ret = true;
+ else
+ ret = false;
+ }
rcu_read_unlock();
return ret;
}
EXPORT_SYMBOL_GPL(tcp_peer_is_proven);
+void tcp_fetch_timewait_stamp(struct sock *sk, struct dst_entry *dst)
+{
+ struct tcp_metrics_block *tm;
+
+ rcu_read_lock();
+ tm = tcp_get_metrics(sk, dst, true);
+ if (tm) {
+ struct tcp_sock *tp = tcp_sk(sk);
+
+ if ((u32)get_seconds() - tm->tcpm_ts_stamp <= TCP_PAWS_MSL) {
+ tp->rx_opt.ts_recent_stamp = tm->tcpm_ts_stamp;
+ tp->rx_opt.ts_recent = tm->tcpm_ts;
+ }
+ }
+ rcu_read_unlock();
+}
+EXPORT_SYMBOL_GPL(tcp_fetch_timewait_stamp);
+
+/* VJ's idea. Save last timestamp seen from this destination and hold
+ * it at least for normal timewait interval to use for duplicate
+ * segment detection in subsequent connections, before they enter
+ * synchronized state.
+ */
+bool tcp_remember_stamp(struct sock *sk)
+{
+ struct dst_entry *dst = __sk_dst_get(sk);
+ bool ret = false;
+
+ if (dst) {
+ struct tcp_metrics_block *tm;
+
+ rcu_read_lock();
+ tm = tcp_get_metrics(sk, dst, true);
+ if (tm) {
+ struct tcp_sock *tp = tcp_sk(sk);
+
+ if ((s32)(tm->tcpm_ts - tp->rx_opt.ts_recent) <= 0 ||
+ ((u32)get_seconds() - tm->tcpm_ts_stamp > TCP_PAWS_MSL &&
+ tm->tcpm_ts_stamp <= (u32)tp->rx_opt.ts_recent_stamp)) {
+ tm->tcpm_ts_stamp = (u32)tp->rx_opt.ts_recent_stamp;
+ tm->tcpm_ts = tp->rx_opt.ts_recent;
+ }
+ ret = true;
+ }
+ rcu_read_unlock();
+ }
+ return ret;
+}
+
+bool tcp_tw_remember_stamp(struct inet_timewait_sock *tw)
+{
+ struct tcp_metrics_block *tm;
+ bool ret = false;
+
+ rcu_read_lock();
+ tm = __tcp_get_metrics_tw(tw);
+ if (tw) {
+ const struct tcp_timewait_sock *tcptw;
+ struct sock *sk = (struct sock *) tw;
+
+ tcptw = tcp_twsk(sk);
+ if ((s32)(tm->tcpm_ts - tcptw->tw_ts_recent) <= 0 ||
+ ((u32)get_seconds() - tm->tcpm_ts_stamp > TCP_PAWS_MSL &&
+ tm->tcpm_ts_stamp <= (u32)tcptw->tw_ts_recent_stamp)) {
+ tm->tcpm_ts_stamp = (u32)tcptw->tw_ts_recent_stamp;
+ tm->tcpm_ts = tcptw->tw_ts_recent;
+ }
+ ret = true;
+ }
+ rcu_read_unlock();
+
+ return ret;
+}
+
static unsigned long tcpmhash_entries;
static int __init set_tcpmhash_entries(char *str)
{