linux/net/rxrpc/proc.c
David Howells 245500d853 rxrpc: Rewrite the client connection manager
Rewrite the rxrpc client connection manager so that it can support multiple
connections for a given security key to a peer.  The following changes are
made:

 (1) For each open socket, the code currently maintains an rbtree with the
     connections placed into it, keyed by communications parameters.  This
     is tricky to maintain as connections can be culled from the tree or
     replaced within it.  Connections can require replacement for a number
     of reasons, e.g. their IDs span too great a range for the IDR data
     type to represent efficiently, the call ID numbers on that conn would
     overflow or the conn got aborted.

     This is changed so that there's now a connection bundle object placed
     in the tree, keyed on the same parameters.  The bundle, however, does
     not need to be replaced.

 (2) An rxrpc_bundle object can now manage the available channels for a set
     of parallel connections.  The lock that manages this is moved there
     from the rxrpc_connection struct (channel_lock).

 (3) There'a a dummy bundle for all incoming connections to share so that
     they have a channel_lock too.  It might be better to give each
     incoming connection its own bundle.  This bundle is not needed to
     manage which channels incoming calls are made on because that's the
     solely at whim of the client.

 (4) The restrictions on how many client connections are around are
     removed.  Instead, a previous patch limits the number of client calls
     that can be allocated.  Ordinarily, client connections are reaped
     after 2 minutes on the idle queue, but when more than a certain number
     of connections are in existence, the reaper starts reaping them after
     2s of idleness instead to get the numbers back down.

     It could also be made such that new call allocations are forced to
     wait until the number of outstanding connections subsides.

Signed-off-by: David Howells <dhowells@redhat.com>
2020-09-08 21:11:43 +01:00

337 lines
8.1 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/* /proc/net/ support for AF_RXRPC
*
* Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*/
#include <linux/module.h>
#include <net/sock.h>
#include <net/af_rxrpc.h>
#include "ar-internal.h"
static const char *const rxrpc_conn_states[RXRPC_CONN__NR_STATES] = {
[RXRPC_CONN_UNUSED] = "Unused ",
[RXRPC_CONN_CLIENT] = "Client ",
[RXRPC_CONN_SERVICE_PREALLOC] = "SvPrealc",
[RXRPC_CONN_SERVICE_UNSECURED] = "SvUnsec ",
[RXRPC_CONN_SERVICE_CHALLENGING] = "SvChall ",
[RXRPC_CONN_SERVICE] = "SvSecure",
[RXRPC_CONN_REMOTELY_ABORTED] = "RmtAbort",
[RXRPC_CONN_LOCALLY_ABORTED] = "LocAbort",
};
/*
* generate a list of extant and dead calls in /proc/net/rxrpc_calls
*/
static void *rxrpc_call_seq_start(struct seq_file *seq, loff_t *_pos)
__acquires(rcu)
__acquires(rxnet->call_lock)
{
struct rxrpc_net *rxnet = rxrpc_net(seq_file_net(seq));
rcu_read_lock();
read_lock(&rxnet->call_lock);
return seq_list_start_head(&rxnet->calls, *_pos);
}
static void *rxrpc_call_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
struct rxrpc_net *rxnet = rxrpc_net(seq_file_net(seq));
return seq_list_next(v, &rxnet->calls, pos);
}
static void rxrpc_call_seq_stop(struct seq_file *seq, void *v)
__releases(rxnet->call_lock)
__releases(rcu)
{
struct rxrpc_net *rxnet = rxrpc_net(seq_file_net(seq));
read_unlock(&rxnet->call_lock);
rcu_read_unlock();
}
static int rxrpc_call_seq_show(struct seq_file *seq, void *v)
{
struct rxrpc_local *local;
struct rxrpc_sock *rx;
struct rxrpc_peer *peer;
struct rxrpc_call *call;
struct rxrpc_net *rxnet = rxrpc_net(seq_file_net(seq));
unsigned long timeout = 0;
rxrpc_seq_t tx_hard_ack, rx_hard_ack;
char lbuff[50], rbuff[50];
if (v == &rxnet->calls) {
seq_puts(seq,
"Proto Local "
" Remote "
" SvID ConnID CallID End Use State Abort "
" DebugId TxSeq TW RxSeq RW RxSerial RxTimo\n");
return 0;
}
call = list_entry(v, struct rxrpc_call, link);
rx = rcu_dereference(call->socket);
if (rx) {
local = READ_ONCE(rx->local);
if (local)
sprintf(lbuff, "%pISpc", &local->srx.transport);
else
strcpy(lbuff, "no_local");
} else {
strcpy(lbuff, "no_socket");
}
peer = call->peer;
if (peer)
sprintf(rbuff, "%pISpc", &peer->srx.transport);
else
strcpy(rbuff, "no_connection");
if (call->state != RXRPC_CALL_SERVER_PREALLOC) {
timeout = READ_ONCE(call->expect_rx_by);
timeout -= jiffies;
}
tx_hard_ack = READ_ONCE(call->tx_hard_ack);
rx_hard_ack = READ_ONCE(call->rx_hard_ack);
seq_printf(seq,
"UDP %-47.47s %-47.47s %4x %08x %08x %s %3u"
" %-8.8s %08x %08x %08x %02x %08x %02x %08x %06lx\n",
lbuff,
rbuff,
call->service_id,
call->cid,
call->call_id,
rxrpc_is_service_call(call) ? "Svc" : "Clt",
atomic_read(&call->usage),
rxrpc_call_states[call->state],
call->abort_code,
call->debug_id,
tx_hard_ack, READ_ONCE(call->tx_top) - tx_hard_ack,
rx_hard_ack, READ_ONCE(call->rx_top) - rx_hard_ack,
call->rx_serial,
timeout);
return 0;
}
const struct seq_operations rxrpc_call_seq_ops = {
.start = rxrpc_call_seq_start,
.next = rxrpc_call_seq_next,
.stop = rxrpc_call_seq_stop,
.show = rxrpc_call_seq_show,
};
/*
* generate a list of extant virtual connections in /proc/net/rxrpc_conns
*/
static void *rxrpc_connection_seq_start(struct seq_file *seq, loff_t *_pos)
__acquires(rxnet->conn_lock)
{
struct rxrpc_net *rxnet = rxrpc_net(seq_file_net(seq));
read_lock(&rxnet->conn_lock);
return seq_list_start_head(&rxnet->conn_proc_list, *_pos);
}
static void *rxrpc_connection_seq_next(struct seq_file *seq, void *v,
loff_t *pos)
{
struct rxrpc_net *rxnet = rxrpc_net(seq_file_net(seq));
return seq_list_next(v, &rxnet->conn_proc_list, pos);
}
static void rxrpc_connection_seq_stop(struct seq_file *seq, void *v)
__releases(rxnet->conn_lock)
{
struct rxrpc_net *rxnet = rxrpc_net(seq_file_net(seq));
read_unlock(&rxnet->conn_lock);
}
static int rxrpc_connection_seq_show(struct seq_file *seq, void *v)
{
struct rxrpc_connection *conn;
struct rxrpc_net *rxnet = rxrpc_net(seq_file_net(seq));
char lbuff[50], rbuff[50];
if (v == &rxnet->conn_proc_list) {
seq_puts(seq,
"Proto Local "
" Remote "
" SvID ConnID End Use State Key "
" Serial ISerial CallId0 CallId1 CallId2 CallId3\n"
);
return 0;
}
conn = list_entry(v, struct rxrpc_connection, proc_link);
if (conn->state == RXRPC_CONN_SERVICE_PREALLOC) {
strcpy(lbuff, "no_local");
strcpy(rbuff, "no_connection");
goto print;
}
sprintf(lbuff, "%pISpc", &conn->params.local->srx.transport);
sprintf(rbuff, "%pISpc", &conn->params.peer->srx.transport);
print:
seq_printf(seq,
"UDP %-47.47s %-47.47s %4x %08x %s %3u"
" %s %08x %08x %08x %08x %08x %08x %08x\n",
lbuff,
rbuff,
conn->service_id,
conn->proto.cid,
rxrpc_conn_is_service(conn) ? "Svc" : "Clt",
atomic_read(&conn->usage),
rxrpc_conn_states[conn->state],
key_serial(conn->params.key),
atomic_read(&conn->serial),
conn->hi_serial,
conn->channels[0].call_id,
conn->channels[1].call_id,
conn->channels[2].call_id,
conn->channels[3].call_id);
return 0;
}
const struct seq_operations rxrpc_connection_seq_ops = {
.start = rxrpc_connection_seq_start,
.next = rxrpc_connection_seq_next,
.stop = rxrpc_connection_seq_stop,
.show = rxrpc_connection_seq_show,
};
/*
* generate a list of extant virtual peers in /proc/net/rxrpc/peers
*/
static int rxrpc_peer_seq_show(struct seq_file *seq, void *v)
{
struct rxrpc_peer *peer;
time64_t now;
char lbuff[50], rbuff[50];
if (v == SEQ_START_TOKEN) {
seq_puts(seq,
"Proto Local "
" Remote "
" Use CW MTU LastUse RTT RTO\n"
);
return 0;
}
peer = list_entry(v, struct rxrpc_peer, hash_link);
sprintf(lbuff, "%pISpc", &peer->local->srx.transport);
sprintf(rbuff, "%pISpc", &peer->srx.transport);
now = ktime_get_seconds();
seq_printf(seq,
"UDP %-47.47s %-47.47s %3u"
" %3u %5u %6llus %8u %8u\n",
lbuff,
rbuff,
atomic_read(&peer->usage),
peer->cong_cwnd,
peer->mtu,
now - peer->last_tx_at,
peer->srtt_us >> 3,
jiffies_to_usecs(peer->rto_j));
return 0;
}
static void *rxrpc_peer_seq_start(struct seq_file *seq, loff_t *_pos)
__acquires(rcu)
{
struct rxrpc_net *rxnet = rxrpc_net(seq_file_net(seq));
unsigned int bucket, n;
unsigned int shift = 32 - HASH_BITS(rxnet->peer_hash);
void *p;
rcu_read_lock();
if (*_pos >= UINT_MAX)
return NULL;
n = *_pos & ((1U << shift) - 1);
bucket = *_pos >> shift;
for (;;) {
if (bucket >= HASH_SIZE(rxnet->peer_hash)) {
*_pos = UINT_MAX;
return NULL;
}
if (n == 0) {
if (bucket == 0)
return SEQ_START_TOKEN;
*_pos += 1;
n++;
}
p = seq_hlist_start_rcu(&rxnet->peer_hash[bucket], n - 1);
if (p)
return p;
bucket++;
n = 1;
*_pos = (bucket << shift) | n;
}
}
static void *rxrpc_peer_seq_next(struct seq_file *seq, void *v, loff_t *_pos)
{
struct rxrpc_net *rxnet = rxrpc_net(seq_file_net(seq));
unsigned int bucket, n;
unsigned int shift = 32 - HASH_BITS(rxnet->peer_hash);
void *p;
if (*_pos >= UINT_MAX)
return NULL;
bucket = *_pos >> shift;
p = seq_hlist_next_rcu(v, &rxnet->peer_hash[bucket], _pos);
if (p)
return p;
for (;;) {
bucket++;
n = 1;
*_pos = (bucket << shift) | n;
if (bucket >= HASH_SIZE(rxnet->peer_hash)) {
*_pos = UINT_MAX;
return NULL;
}
if (n == 0) {
*_pos += 1;
n++;
}
p = seq_hlist_start_rcu(&rxnet->peer_hash[bucket], n - 1);
if (p)
return p;
}
}
static void rxrpc_peer_seq_stop(struct seq_file *seq, void *v)
__releases(rcu)
{
rcu_read_unlock();
}
const struct seq_operations rxrpc_peer_seq_ops = {
.start = rxrpc_peer_seq_start,
.next = rxrpc_peer_seq_next,
.stop = rxrpc_peer_seq_stop,
.show = rxrpc_peer_seq_show,
};