From db7f00b8dba6d687b6ab1f2e9309acfd214fcb4b Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Thu, 16 Mar 2017 15:43:19 -0700 Subject: [PATCH] tcp: tcp_get_info() should read tcp_time_stamp later Commit b369e7fd41f7 ("tcp: make TCP_INFO more consistent") moved lock_sock_fast() earlier in tcp_get_info() This has the minor effect that jiffies value being sampled at the beginning of tcp_get_info() is more likely to be off by one, and we report big tcpi_last_data_sent values (like 0xFFFFFFFF). Since we lock the socket, fetching tcp_time_stamp right before doing the jiffies_to_msecs() calls is enough to remove these wrong values. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- net/ipv4/tcp.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index cf45555..1e319a5 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -2770,7 +2770,7 @@ void tcp_get_info(struct sock *sk, struct tcp_info *info) { const struct tcp_sock *tp = tcp_sk(sk); /* iff sk_type == SOCK_STREAM */ const struct inet_connection_sock *icsk = inet_csk(sk); - u32 now = tcp_time_stamp, intv; + u32 now, intv; u64 rate64; bool slow; u32 rate; @@ -2839,6 +2839,7 @@ void tcp_get_info(struct sock *sk, struct tcp_info *info) info->tcpi_retrans = tp->retrans_out; info->tcpi_fackets = tp->fackets_out; + now = tcp_time_stamp; info->tcpi_last_data_sent = jiffies_to_msecs(now - tp->lsndtime); info->tcpi_last_data_recv = jiffies_to_msecs(now - icsk->icsk_ack.lrcvtime); info->tcpi_last_ack_recv = jiffies_to_msecs(now - tp->rcv_tstamp); -- 2.7.4