While debugging another problem, I noticed that the first number on
each line read from /proc/net/tcp (and from /proc/net/tcp6) was
meaningless. The netstat program ignores this number, and I know of
no other readers of /proc/net/tcp{,6}. So perhaps this is only a
cosmetic bug. Nevertheless, in debugging another problem with the
lines produced by /proc/net/tcp, these meaningless numbers caused
confusion.
On a linux-2.6.0-test7 system, it looks like this:
$ cat /proc/net/tcp
sl local_address rem_address st tx_queue rx_queue tr tm->when retrnsmt
uid timeout inode
1: 0100007F:2260 00000000:0000 0A 00000000:00000000 00:00000000 00000000
1000 0 2253 1 cdb27440 3000 0 0 2 -1
1: 00000000:1F40 00000000:0000 0A 00000000:00000000 00:00000000 00000000
0 0 1862 1 cf1e5060 3000 0 0 2 -1
1: 0100007F:0A43 00000000:0000 0A 00000000:00000000 00:00000000 00000000
1000 0 2259 1 cc949460 3000 0 0 2 -1
1: 00000000:0203 00000000:0000 0A 00000000:00000000 00:00000000 00000000
0 0 1256 1 cf1e53e0 3000 0 0 2 -1
1: 0100007F:2266 00000000:0000 0A 00000000:00000000 00:00000000 00000000
1000 0 2255 1 cc949b60 3000 0 0 2 -1
1: 0100007F:2B48 00000000:0000 0A 00000000:00000000 00:00000000 00000000
1000 0 2257 1 cc9497e0 3000 0 0 2 -1
2: 0100007F:16E9 00000000:0000 0A 00000000:00000000 00:00000000 00000000
103 0 1250 1 cf1e5760 3000 0 0 2 -1
2: 0100007F:2B6F 00000000:0000 0A 00000000:00000000 00:00000000 00000000
1000 0 2261 1 cc9490e0 3000 0 0 2 -1
2: 0100007F:0035 00000000:0000 0A 00000000:00000000 00:00000000 00000000
0 0 1141 1 c13443c0 3000 0 0 2 -1
2: 0100007F:0C38 00000000:0000 0A 00000000:00000000 00:00000000 00000000
1000 0 2265 1 cc927800 3000 0 0 2 -1
2: 0100007F:09DD 00000000:0000 0A 00000000:00000000 00:00000000 00000000
1000 0 2263 1 cc927b80 3000 0 0 2 -1
2: B8425C42:8001 0C00000A:0016 01 00000000:00000000 02:006B7C78 00000000
1000 0 2273 2 cc927100 205 40 0 3 -1
2: B8425C42:8000 52001A12:0016 01 00000000:00000000 02:006B4970 00000000
1000 0 2249 2 cdb270c0 262 40 0 3 -1
On a linux-2.4.21 system, this first number just counts up like this:
$ cat /proc/net/tcp
sl local_address rem_address st tx_queue rx_queue tr tm->when retrnsmt
uid timeout inode
0: 00000000:1F40 00000000:0000 0A 00000000:00000000 00:00000000 00000000
0 0 580 1 c702f820 300 0 0 2 -1
1: 00000000:16E9 00000000:0000 0A 00000000:00000000 00:00000000 00000000
101 0 297102 1 c718dba0 300 0 0 2 -1
2: 00000000:006F 00000000:0000 0A 00000000:00000000 00:00000000 00000000
0 0 145 1 c77e5420 300 0 0 2 -1
3: 00000000:1770 00000000:0000 0A 00000000:00000000 00:00000000 00000000
0 0 840 1 c6cf94c0 300 0 0 2 -1
4: 0C00000A:0035 00000000:0000 0A 00000000:00000000 00:00000000 00000000
0 0 2627 1 c5fd2b60 300 0 0 2 -1
5: 92425C42:0035 00000000:0000 0A 00000000:00000000 00:00000000 00000000
0 0 2625 1 c5fd2080 300 0 0 2 -1
6: 0100007F:0035 00000000:0000 0A 00000000:00000000 00:00000000 00000000
0 0 332 1 c718d0c0 300 0 0 2 -1
7: 00000000:0016 00000000:0000 0A 00000000:00000000 00:00000000 00000000
0 0 76922 1 c2eac880 300 0 0 2 -1
8: 00000000:0019 00000000:0000 0A 00000000:00000000 00:00000000 00000000
0 0 403 1 c718d800 300 0 0 2 -1
9: 0100007F:177A 00000000:0000 0A 00000000:00000000 00:00000000 00000000
1000 0 314391 1 c2eacc20 300 0 0 2 -1
However, on a linux-2.4.21 system with ipv6 listeners, the numbers are
shared between ipv4 and ipv6:
$ cat /proc/net/tcp
sl local_address rem_address st tx_queue rx_queue tr tm->when retrnsmt
uid timeout inode
0: 00000000:1F40 00000000:0000 0A 00000000:00000000 00:00000000 00000000
0 0 580 1 c702f820 300 0 0 2 -1
1: 00000000:16E9 00000000:0000 0A 00000000:00000000 00:00000000 00000000
101 0 297102 1 c718dba0 300 0 0 2 -1
2: 00000000:006F 00000000:0000 0A 00000000:00000000 00:00000000 00000000
0 0 145 1 c77e5420 300 0 0 2 -1
4: 00000000:1770 00000000:0000 0A 00000000:00000000 00:00000000 00000000
0 0 840 1 c6cf94c0 300 0 0 2 -1
5: 0C00000A:0035 00000000:0000 0A 00000000:00000000 00:00000000 00000000
0 0 2627 1 c5fd2b60 300 0 0 2 -1
6: 92425C42:0035 00000000:0000 0A 00000000:00000000 00:00000000 00000000
0 0 2625 1 c5fd2080 300 0 0 2 -1
7: 0100007F:0035 00000000:0000 0A 00000000:00000000 00:00000000 00000000
0 0 332 1 c718d0c0 300 0 0 2 -1
8: 00000000:0016 00000000:0000 0A 00000000:00000000 00:00000000 00000000
0 0 76922 1 c2eac880 300 0 0 2 -1
9: 00000000:0019 00000000:0000 0A 00000000:00000000 00:00000000 00000000
0 0 403 1 c718d800 300 0 0 2 -1
10: 0100007F:177A 00000000:0000 0A 00000000:00000000 00:00000000 00000000
1000 0 314391 1 c2eacc20 300 0 0 2 -1
$ cat /proc/net/tcp6
sl local_address remote_address
st tx_queue rx_queue tr tm->when retrnsmt uid timeout inode
3: 00000000000000000000000000000000:0050
00000000000000000000000000000000:0000 0A 00000000:00000000 00:00000000 00000000
0 0 6630 1 c702fbc0 300 0 0 2 -1
I am not sure what the behavior is supposed to be. Is there a spec
anywhere for the interface with /proc/net/tcp?
The patch below changes it to always count up from zero, without
sharing the numbers between ipv4 and ipv6. This is an improvement
over linux-2.6.0-test7 behavior, but without a spec I cannot be sure
what the correct behavior would be.
This patch can be applied before, after, alone, or with the other patch I
submitted earlier today. This patch is the less important of the two.
I welcome comments.
-Tim Shepard
shep@xxxxxxxxxxxx
--- ../pristine/linux-2.6.0-test7/net/ipv4/tcp_ipv4.c 2003-10-08
15:24:03.000000000 -0400
+++ net/ipv4/tcp_ipv4.c 2003-10-13 22:33:10.000000000 -0400
@@ -2145,7 +2145,6 @@
if (!sk)
continue;
- ++st->num;
if (sk->sk_family == st->family) {
rc = sk;
goto out;
@@ -2159,7 +2158,7 @@
for (st->sbucket = 0; st->sbucket < TCP_SYNQ_HSIZE;
++st->sbucket) {
for (req =
tp->listen_opt->syn_table[st->sbucket];
- req; req = req->dl_next, ++st->num) {
+ req; req = req->dl_next) {
if (req->class->family != st->family)
continue;
rc = req;
@@ -2181,6 +2180,8 @@
struct sock *sk = cur;
struct tcp_iter_state* st = seq->private;
+ ++st->num;
+
if (st->state == TCP_SEQ_STATE_OPENREQ) {
struct open_request *req = cur;
@@ -2188,7 +2189,6 @@
req = req->dl_next;
while (1) {
while (req) {
- ++st->num;
if (req->class->family == st->family) {
cur = req;
goto out;
@@ -2254,7 +2254,6 @@
read_lock(&tcp_ehash[st->bucket].lock);
sk_for_each(sk, node, &tcp_ehash[st->bucket].chain) {
if (sk->sk_family != st->family) {
- ++st->num;
continue;
}
rc = sk;
@@ -2264,7 +2263,6 @@
tw_for_each(tw, node,
&tcp_ehash[st->bucket + tcp_ehash_size].chain) {
if (tw->tw_family != st->family) {
- ++st->num;
continue;
}
rc = tw;
@@ -2284,12 +2282,13 @@
struct hlist_node *node;
struct tcp_iter_state* st = seq->private;
+ ++st->num;
+
if (st->state == TCP_SEQ_STATE_TIME_WAIT) {
tw = cur;
tw = tw_next(tw);
get_tw:
while (tw && tw->tw_family != st->family) {
- ++st->num;
tw = tw_next(tw);
}
if (tw) {
@@ -2311,7 +2310,6 @@
sk_for_each_from(sk, node) {
if (sk->sk_family == st->family)
goto found;
- ++st->num;
}
st->state = TCP_SEQ_STATE_TIME_WAIT;
@@ -2354,6 +2352,8 @@
static void *tcp_seq_start(struct seq_file *seq, loff_t *pos)
{
+ struct tcp_iter_state* st = seq->private;
+ st->num = 0;
return *pos ? tcp_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
}
|