Commit 47da8ee6 authored by Sridhar Samudrala's avatar Sridhar Samudrala Committed by David S. Miller
Browse files

[TCP]: Export accept queue len of a TCP listening socket via rx_queue 



While debugging a TCP server hang issue, we noticed that currently there is
no way for a user to get the acceptq backlog value for a TCP listen socket.

All the standard networking utilities that display socket info like netstat,
ss and /proc/net/tcp have 2 fields called rx_queue and tx_queue. These
fields do not mean much for listening sockets. This patch uses one of these
unused fields(rx_queue) to export the accept queue len for listening sockets.

Signed-off-by: default avatarSridhar Samudrala <sri@us.ibm.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent c7bdb545

net/ipv4/tcp_diag.c

+4 −1
Original line number Diff line number Diff line
@@ -26,6 +26,9 @@ static void tcp_diag_get_info(struct sock *sk, struct inet_diag_msg *r, 
	const struct tcp_sock *tp = tcp_sk(sk);

	struct tcp_info *info = _info;



	if (sk->sk_state == TCP_LISTEN)

		r->idiag_rqueue = sk->sk_ack_backlog;

	else

		r->idiag_rqueue = tp->rcv_nxt - tp->copied_seq;

	r->idiag_wqueue = tp->write_seq - tp->snd_una;

	if (info != NULL)

net/ipv4/tcp_ipv4.c

+2 −1
Original line number Diff line number Diff line
@@ -1726,7 +1726,8 @@ static void get_tcp4_sock(struct sock *sp, char *tmpbuf, int i) 
	sprintf(tmpbuf, "%4d: %08X:%04X %08X:%04X %02X %08X:%08X %02X:%08lX "

			"%08X %5d %8d %lu %d %p %u %u %u %u %d",

		i, src, srcp, dest, destp, sp->sk_state,

		tp->write_seq - tp->snd_una, tp->rcv_nxt - tp->copied_seq,

		tp->write_seq - tp->snd_una,

		(sp->sk_state == TCP_LISTEN) ? sp->sk_ack_backlog : (tp->rcv_nxt - tp->copied_seq),

		timer_active,

		jiffies_to_clock_t(timer_expires - jiffies),

		icsk->icsk_retransmits,

net/ipv6/tcp_ipv6.c

+2 −1
Original line number Diff line number Diff line
@@ -1469,7 +1469,8 @@ static void get_tcp6_sock(struct seq_file *seq, struct sock *sp, int i) 
		   dest->s6_addr32[0], dest->s6_addr32[1],

		   dest->s6_addr32[2], dest->s6_addr32[3], destp,

		   sp->sk_state, 

		   tp->write_seq-tp->snd_una, tp->rcv_nxt-tp->copied_seq,

		   tp->write_seq-tp->snd_una,

		   (sp->sk_state == TCP_LISTEN) ? sp->sk_ack_backlog : (tp->rcv_nxt - tp->copied_seq),

		   timer_active,

		   jiffies_to_clock_t(timer_expires - jiffies),

		   icsk->icsk_retransmits,

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