From d82bae12dc38d79a2b77473f5eb0612a3d69c55b Mon Sep 17 00:00:00 2001 From: Soheil Hassas Yeganeh Date: Wed, 15 Mar 2017 16:30:45 -0400 Subject: tcp: remove per-destination timestamp cache Commit 8a5bd45f6616 (tcp: randomize tcp timestamp offsets for each connection) randomizes TCP timestamps per connection. After this commit, there is no guarantee that the timestamps received from the same destination are monotonically increasing. As a result, the per-destination timestamp cache in TCP metrics (i.e., tcpm_ts in struct tcp_metrics_block) is broken and cannot be relied upon. Remove the per-destination timestamp cache and all related code paths. Note that this cache was already broken for caching timestamps of multiple machines behind a NAT sharing the same address. Signed-off-by: Soheil Hassas Yeganeh Signed-off-by: Eric Dumazet Signed-off-by: Neal Cardwell Signed-off-by: Yuchung Cheng Cc: Lutz Vieweg Cc: Florian Westphal Signed-off-by: David S. Miller --- net/ipv4/tcp_minisocks.c | 22 ++++------------------ 1 file changed, 4 insertions(+), 18 deletions(-) (limited to 'net/ipv4/tcp_minisocks.c') diff --git a/net/ipv4/tcp_minisocks.c b/net/ipv4/tcp_minisocks.c index 7e16243cdb58..692f974e5abe 100644 --- a/net/ipv4/tcp_minisocks.c +++ b/net/ipv4/tcp_minisocks.c @@ -94,7 +94,6 @@ tcp_timewait_state_process(struct inet_timewait_sock *tw, struct sk_buff *skb, struct tcp_options_received tmp_opt; struct tcp_timewait_sock *tcptw = tcp_twsk((struct sock *)tw); bool paws_reject = false; - struct inet_timewait_death_row *tcp_death_row = &sock_net((struct sock*)tw)->ipv4.tcp_death_row; tmp_opt.saw_tstamp = 0; if (th->doff > (sizeof(*th) >> 2) && tcptw->tw_ts_recent_stamp) { @@ -149,12 +148,7 @@ tcp_timewait_state_process(struct inet_timewait_sock *tw, struct sk_buff *skb, tcptw->tw_ts_recent = tmp_opt.rcv_tsval; } - if (tcp_death_row->sysctl_tw_recycle && - tcptw->tw_ts_recent_stamp && - tcp_tw_remember_stamp(tw)) - inet_twsk_reschedule(tw, tw->tw_timeout); - else - inet_twsk_reschedule(tw, TCP_TIMEWAIT_LEN); + inet_twsk_reschedule(tw, TCP_TIMEWAIT_LEN); return TCP_TW_ACK; } @@ -259,12 +253,8 @@ void tcp_time_wait(struct sock *sk, int state, int timeo) const struct inet_connection_sock *icsk = inet_csk(sk); const struct tcp_sock *tp = tcp_sk(sk); struct inet_timewait_sock *tw; - bool recycle_ok = false; struct inet_timewait_death_row *tcp_death_row = &sock_net(sk)->ipv4.tcp_death_row; - if (tcp_death_row->sysctl_tw_recycle && tp->rx_opt.ts_recent_stamp) - recycle_ok = tcp_remember_stamp(sk); - tw = inet_twsk_alloc(sk, tcp_death_row, state); if (tw) { @@ -317,13 +307,9 @@ void tcp_time_wait(struct sock *sk, int state, int timeo) if (timeo < rto) timeo = rto; - if (recycle_ok) { - tw->tw_timeout = rto; - } else { - tw->tw_timeout = TCP_TIMEWAIT_LEN; - if (state == TCP_TIME_WAIT) - timeo = TCP_TIMEWAIT_LEN; - } + tw->tw_timeout = TCP_TIMEWAIT_LEN; + if (state == TCP_TIME_WAIT) + timeo = TCP_TIMEWAIT_LEN; inet_twsk_schedule(tw, timeo); /* Linkage updates. */ -- cgit v1.2.3 From e5907459ce7e2b6bc397007865ad492f10c2aeac Mon Sep 17 00:00:00 2001 From: Alexander Duyck Date: Fri, 24 Mar 2017 10:08:00 -0700 Subject: tcp: Record Rx hash and NAPI ID in tcp_child_process While working on some recent busy poll changes we found that child sockets were being instantiated without NAPI ID being set. In our first attempt to fix it, it was suggested that we should just pull programming the NAPI ID into the function itself since all callers will need to have it set. In addition to the NAPI ID change I have dropped the code that was populating the Rx hash since it was actually being populated in tcp_get_cookie_sock. Reported-by: Sridhar Samudrala Signed-off-by: Alexander Duyck Acked-by: Eric Dumazet Signed-off-by: David S. Miller --- net/ipv4/tcp_ipv4.c | 2 -- net/ipv4/tcp_minisocks.c | 4 ++++ net/ipv6/tcp_ipv6.c | 2 -- 3 files changed, 4 insertions(+), 4 deletions(-) (limited to 'net/ipv4/tcp_minisocks.c') diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index 7482b5d11861..20cbd2f07f28 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -1409,8 +1409,6 @@ int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb) if (!nsk) goto discard; if (nsk != sk) { - sock_rps_save_rxhash(nsk, skb); - sk_mark_napi_id(nsk, skb); if (tcp_child_process(sk, nsk, skb)) { rsk = nsk; goto reset; diff --git a/net/ipv4/tcp_minisocks.c b/net/ipv4/tcp_minisocks.c index 1e217948be62..8f6373b0cd77 100644 --- a/net/ipv4/tcp_minisocks.c +++ b/net/ipv4/tcp_minisocks.c @@ -26,6 +26,7 @@ #include #include #include +#include int sysctl_tcp_abort_on_overflow __read_mostly; @@ -799,6 +800,9 @@ int tcp_child_process(struct sock *parent, struct sock *child, int ret = 0; int state = child->sk_state; + /* record NAPI ID of child */ + sk_mark_napi_id(child, skb); + tcp_segs_in(tcp_sk(child), skb); if (!sock_owned_by_user(child)) { ret = tcp_rcv_state_process(child, skb); diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index 031a8c019f7a..8e42e8f54b70 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -1293,8 +1293,6 @@ static int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb) goto discard; if (nsk != sk) { - sock_rps_save_rxhash(nsk, skb); - sk_mark_napi_id(nsk, skb); if (tcp_child_process(sk, nsk, skb)) goto reset; if (opt_skb) -- cgit v1.2.3