mptcp: add and use MIB counter infrastructure

Exported via same /proc file as the Linux TCP MIB counters, so "netstat -s"
or "nstat" will show them automatically.

The MPTCP MIB counters are allocated in a distinct pcpu area in order to
avoid bloating/wasting TCP pcpu memory.

Counters are allocated once the first MPTCP socket is created in a
network namespace and free'd on exit.

If no sockets have been allocated, all-zero mptcp counters are shown.

The MIB counter list is taken from the multipath-tcp.org kernel, but
only a few counters have been picked up so far.  The counter list can
be increased at any time later on.

v2 -> v3:
 - remove 'inline' in foo.c files (David S. Miller)

Co-developed-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Florian Westphal 2020-03-27 14:48:50 -07:00 committed by David S. Miller
parent 5147dfb508
commit fc518953bc
9 changed files with 172 additions and 15 deletions

View File

@ -12,6 +12,8 @@
#include <linux/tcp.h>
#include <linux/types.h>
struct seq_file;
/* MPTCP sk_buff extension data */
struct mptcp_ext {
u64 data_ack;
@ -123,6 +125,7 @@ static inline bool mptcp_skb_can_collapse(const struct sk_buff *to,
bool mptcp_sk_is_subflow(const struct sock *sk);
void mptcp_seq_show(struct seq_file *seq);
#else
static inline void mptcp_init(void)
@ -194,6 +197,7 @@ static inline bool mptcp_sk_is_subflow(const struct sock *sk)
return false;
}
static inline void mptcp_seq_show(struct seq_file *seq) { }
#endif /* CONFIG_MPTCP */
#if IS_ENABLED(CONFIG_MPTCP_IPV6)

View File

@ -27,6 +27,9 @@ struct netns_mib {
#if IS_ENABLED(CONFIG_TLS)
DEFINE_SNMP_STAT(struct linux_tls_mib, tls_statistics);
#endif
#ifdef CONFIG_MPTCP
DEFINE_SNMP_STAT(struct mptcp_mib, mptcp_statistics);
#endif
};
#endif

View File

@ -1793,6 +1793,10 @@ static __net_exit void ipv4_mib_exit_net(struct net *net)
free_percpu(net->mib.net_statistics);
free_percpu(net->mib.ip_statistics);
free_percpu(net->mib.tcp_statistics);
#ifdef CONFIG_MPTCP
/* allocated on demand, see mptcp_init_sock() */
free_percpu(net->mib.mptcp_statistics);
#endif
}
static __net_initdata struct pernet_operations ipv4_mib_ops = {

View File

@ -32,6 +32,7 @@
#include <net/icmp.h>
#include <net/protocol.h>
#include <net/tcp.h>
#include <net/mptcp.h>
#include <net/udp.h>
#include <net/udplite.h>
#include <linux/bottom_half.h>
@ -485,6 +486,7 @@ static int netstat_seq_show(struct seq_file *seq, void *v)
offsetof(struct ipstats_mib, syncp)));
seq_putc(seq, '\n');
mptcp_seq_show(seq);
return 0;
}

View File

@ -1,4 +1,4 @@
# SPDX-License-Identifier: GPL-2.0
obj-$(CONFIG_MPTCP) += mptcp.o
mptcp-y := protocol.o subflow.o options.o token.o crypto.o ctrl.o pm.o diag.o
mptcp-y := protocol.o subflow.o options.o token.o crypto.o ctrl.o pm.o diag.o mib.o

69
net/mptcp/mib.c Normal file
View File

@ -0,0 +1,69 @@
// SPDX-License-Identifier: GPL-2.0-or-later
#include <linux/seq_file.h>
#include <net/ip.h>
#include <net/mptcp.h>
#include <net/snmp.h>
#include <net/net_namespace.h>
#include "mib.h"
static const struct snmp_mib mptcp_snmp_list[] = {
SNMP_MIB_ITEM("MPCapableSYNRX", MPTCP_MIB_MPCAPABLEPASSIVE),
SNMP_MIB_ITEM("MPCapableACKRX", MPTCP_MIB_MPCAPABLEPASSIVEACK),
SNMP_MIB_ITEM("MPCapableFallbackACK", MPTCP_MIB_MPCAPABLEPASSIVEFALLBACK),
SNMP_MIB_ITEM("MPCapableFallbackSYNACK", MPTCP_MIB_MPCAPABLEACTIVEFALLBACK),
SNMP_MIB_ITEM("MPTCPRetrans", MPTCP_MIB_RETRANSSEGS),
SNMP_MIB_ITEM("MPJoinNoTokenFound", MPTCP_MIB_JOINNOTOKEN),
SNMP_MIB_ITEM("MPJoinSynRx", MPTCP_MIB_JOINSYNRX),
SNMP_MIB_ITEM("MPJoinSynAckRx", MPTCP_MIB_JOINSYNACKRX),
SNMP_MIB_ITEM("MPJoinSynAckHMacFailure", MPTCP_MIB_JOINSYNACKMAC),
SNMP_MIB_ITEM("MPJoinAckRx", MPTCP_MIB_JOINACKRX),
SNMP_MIB_ITEM("MPJoinAckHMacFailure", MPTCP_MIB_JOINACKMAC),
SNMP_MIB_ITEM("DSSNotMatching", MPTCP_MIB_DSSNOMATCH),
SNMP_MIB_ITEM("InfiniteMapRx", MPTCP_MIB_INFINITEMAPRX),
SNMP_MIB_SENTINEL
};
/* mptcp_mib_alloc - allocate percpu mib counters
*
* These are allocated when the first mptcp socket is created so
* we do not waste percpu memory if mptcp isn't in use.
*/
bool mptcp_mib_alloc(struct net *net)
{
struct mptcp_mib __percpu *mib = alloc_percpu(struct mptcp_mib);
if (!mib)
return false;
if (cmpxchg(&net->mib.mptcp_statistics, NULL, mib))
free_percpu(mib);
return true;
}
void mptcp_seq_show(struct seq_file *seq)
{
struct net *net = seq->private;
int i;
seq_puts(seq, "MPTcpExt:");
for (i = 0; mptcp_snmp_list[i].name; i++)
seq_printf(seq, " %s", mptcp_snmp_list[i].name);
seq_puts(seq, "\nMPTcpExt:");
if (!net->mib.mptcp_statistics) {
for (i = 0; mptcp_snmp_list[i].name; i++)
seq_puts(seq, " 0");
return;
}
for (i = 0; mptcp_snmp_list[i].name; i++)
seq_printf(seq, " %lu",
snmp_fold_field(net->mib.mptcp_statistics,
mptcp_snmp_list[i].entry));
seq_putc(seq, '\n');
}

40
net/mptcp/mib.h Normal file
View File

@ -0,0 +1,40 @@
/* SPDX-License-Identifier: GPL-2.0-or-later */
enum linux_mptcp_mib_field {
MPTCP_MIB_NUM = 0,
MPTCP_MIB_MPCAPABLEPASSIVE, /* Received SYN with MP_CAPABLE */
MPTCP_MIB_MPCAPABLEPASSIVEACK, /* Received third ACK with MP_CAPABLE */
MPTCP_MIB_MPCAPABLEPASSIVEFALLBACK,/* Server-side fallback during 3-way handshake */
MPTCP_MIB_MPCAPABLEACTIVEFALLBACK, /* Client-side fallback during 3-way handshake */
MPTCP_MIB_RETRANSSEGS, /* Segments retransmitted at the MPTCP-level */
MPTCP_MIB_JOINNOTOKEN, /* Received MP_JOIN but the token was not found */
MPTCP_MIB_JOINSYNRX, /* Received a SYN + MP_JOIN */
MPTCP_MIB_JOINSYNACKRX, /* Received a SYN/ACK + MP_JOIN */
MPTCP_MIB_JOINSYNACKMAC, /* HMAC was wrong on SYN/ACK + MP_JOIN */
MPTCP_MIB_JOINACKRX, /* Received an ACK + MP_JOIN */
MPTCP_MIB_JOINACKMAC, /* HMAC was wrong on ACK + MP_JOIN */
MPTCP_MIB_DSSNOMATCH, /* Received a new mapping that did not match the previous one */
MPTCP_MIB_INFINITEMAPRX, /* Received an infinite mapping */
__MPTCP_MIB_MAX
};
#define LINUX_MIB_MPTCP_MAX __MPTCP_MIB_MAX
struct mptcp_mib {
unsigned long mibs[LINUX_MIB_MPTCP_MAX];
};
static inline void MPTCP_INC_STATS(struct net *net,
enum linux_mptcp_mib_field field)
{
if (likely(net->mib.mptcp_statistics))
SNMP_INC_STATS(net->mib.mptcp_statistics, field);
}
static inline void __MPTCP_INC_STATS(struct net *net,
enum linux_mptcp_mib_field field)
{
if (likely(net->mib.mptcp_statistics))
__SNMP_INC_STATS(net->mib.mptcp_statistics, field);
}
bool mptcp_mib_alloc(struct net *net);

View File

@ -21,6 +21,7 @@
#endif
#include <net/mptcp.h>
#include "protocol.h"
#include "mib.h"
#define MPTCP_SAME_STATE TCP_MAX_STATES
@ -1032,6 +1033,7 @@ static void mptcp_worker(struct work_struct *work)
if (ret < 0)
break;
MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_RETRANSSEGS);
copied += ret;
dfrag->data_len -= ret;
dfrag->offset += ret;
@ -1081,17 +1083,22 @@ static int __mptcp_init_sock(struct sock *sk)
static int mptcp_init_sock(struct sock *sk)
{
int ret = __mptcp_init_sock(sk);
struct net *net = sock_net(sk);
int ret;
if (!mptcp_is_enabled(net))
return -ENOPROTOOPT;
if (unlikely(!net->mib.mptcp_statistics) && !mptcp_mib_alloc(net))
return -ENOMEM;
ret = __mptcp_init_sock(sk);
if (ret)
return ret;
sk_sockets_allocated_inc(sk);
sk->sk_sndbuf = sock_net(sk)->ipv4.sysctl_tcp_wmem[2];
if (!mptcp_is_enabled(sock_net(sk)))
return -ENOPROTOOPT;
return 0;
}
@ -1327,7 +1334,12 @@ static struct sock *mptcp_accept(struct sock *sk, int flags, int *err,
list_add(&subflow->node, &msk->conn_list);
bh_unlock_sock(new_mptcp_sock);
__MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_MPCAPABLEPASSIVEACK);
local_bh_enable();
} else {
MPTCP_INC_STATS(sock_net(sk),
MPTCP_MIB_MPCAPABLEPASSIVEFALLBACK);
}
return newsk;
@ -1448,13 +1460,15 @@ void mptcp_finish_connect(struct sock *ssk)
u64 ack_seq;
subflow = mptcp_subflow_ctx(ssk);
if (!subflow->mp_capable)
return;
sk = subflow->conn;
msk = mptcp_sk(sk);
if (!subflow->mp_capable) {
MPTCP_INC_STATS(sock_net(sk),
MPTCP_MIB_MPCAPABLEACTIVEFALLBACK);
return;
}
pr_debug("msk=%p, token=%u", sk, subflow->token);
mptcp_crypto_key_sha(subflow->remote_key, NULL, &ack_seq);

View File

@ -20,6 +20,13 @@
#endif
#include <net/mptcp.h>
#include "protocol.h"
#include "mib.h"
static void SUBFLOW_REQ_INC_STATS(struct request_sock *req,
enum linux_mptcp_mib_field field)
{
MPTCP_INC_STATS(sock_net(req_to_sk(req)), field);
}
static int subflow_rebuild_header(struct sock *sk)
{
@ -88,8 +95,7 @@ static bool subflow_token_join_request(struct request_sock *req,
msk = mptcp_token_get_sock(subflow_req->token);
if (!msk) {
pr_debug("subflow_req=%p, token=%u - not found\n",
subflow_req, subflow_req->token);
SUBFLOW_REQ_INC_STATS(req, MPTCP_MIB_JOINNOTOKEN);
return false;
}
@ -137,8 +143,14 @@ static void subflow_init_req(struct request_sock *req,
return;
#endif
if (rx_opt.mptcp.mp_capable && rx_opt.mptcp.mp_join)
return;
if (rx_opt.mptcp.mp_capable) {
SUBFLOW_REQ_INC_STATS(req, MPTCP_MIB_MPCAPABLEPASSIVE);
if (rx_opt.mptcp.mp_join)
return;
} else if (rx_opt.mptcp.mp_join) {
SUBFLOW_REQ_INC_STATS(req, MPTCP_MIB_JOINSYNRX);
}
if (rx_opt.mptcp.mp_capable && listener->request_mptcp) {
int err;
@ -237,6 +249,7 @@ static void subflow_finish_connect(struct sock *sk, const struct sk_buff *skb)
subflow, subflow->thmac,
subflow->remote_nonce);
if (!subflow_thmac_valid(subflow)) {
MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_JOINACKMAC);
subflow->mp_join = 0;
goto do_reset;
}
@ -253,6 +266,7 @@ static void subflow_finish_connect(struct sock *sk, const struct sk_buff *skb)
goto do_reset;
subflow->conn_finished = 1;
MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_JOINSYNACKRX);
} else {
do_reset:
tcp_send_active_reset(sk, GFP_ATOMIC);
@ -382,8 +396,10 @@ create_msk:
opt_rx.mptcp.mp_join = 0;
mptcp_get_options(skb, &opt_rx);
if (!opt_rx.mptcp.mp_join ||
!subflow_hmac_valid(req, &opt_rx))
!subflow_hmac_valid(req, &opt_rx)) {
SUBFLOW_REQ_INC_STATS(req, MPTCP_MIB_JOINACKMAC);
return NULL;
}
}
create_child:
@ -420,6 +436,8 @@ create_child:
ctx->conn = (struct sock *)owner;
if (!mptcp_finish_join(child))
goto close_child;
SUBFLOW_REQ_INC_STATS(req, MPTCP_MIB_JOINACKRX);
}
}
@ -535,6 +553,7 @@ static enum mapping_status get_mapping_status(struct sock *ssk)
data_len = mpext->data_len;
if (data_len == 0) {
pr_err("Infinite mapping not handled");
MPTCP_INC_STATS(sock_net(ssk), MPTCP_MIB_INFINITEMAPRX);
return MAPPING_INVALID;
}
@ -578,8 +597,10 @@ static enum mapping_status get_mapping_status(struct sock *ssk)
/* If this skb data are fully covered by the current mapping,
* the new map would need caching, which is not supported
*/
if (skb_is_fully_mapped(ssk, skb))
if (skb_is_fully_mapped(ssk, skb)) {
MPTCP_INC_STATS(sock_net(ssk), MPTCP_MIB_DSSNOMATCH);
return MAPPING_INVALID;
}
/* will validate the next map after consuming the current one */
return MAPPING_OK;