[PATCH net-next 18/19] rxrpc: Move the client conn cache management to the I/O thread
David Howells
dhowells at redhat.com
Fri Dec 23 04:01:56 PST 2022
Move the management of the client connection cache to the I/O thread rather
than managing it from the namespace as an aggregate across all the local
endpoints within the namespace.
This will allow a load of locking to be got rid of in a future patch as
only the I/O thread will be looking at the this.
The downside is that the total number of cached connections on the system
can get higher because the limit is now per-local rather than per-netns.
We can, however, keep the number of client conns in use across the entire
netfs and use that to reduce the expiration time of idle connection.
Signed-off-by: David Howells <dhowells at redhat.com>
cc: Marc Dionne <marc.dionne at auristor.com>
cc: linux-afs at lists.infradead.org
---
net/rxrpc/ar-internal.h | 17 +++++----
net/rxrpc/conn_client.c | 92 ++++++++++++++++------------------------------
net/rxrpc/conn_object.c | 1 -
net/rxrpc/io_thread.c | 4 ++
net/rxrpc/local_object.c | 17 +++++++++
net/rxrpc/net_ns.c | 17 ---------
6 files changed, 62 insertions(+), 86 deletions(-)
diff --git a/net/rxrpc/ar-internal.h b/net/rxrpc/ar-internal.h
index f9527b100b48..038109d6c796 100644
--- a/net/rxrpc/ar-internal.h
+++ b/net/rxrpc/ar-internal.h
@@ -76,13 +76,7 @@ struct rxrpc_net {
bool live;
- bool kill_all_client_conns;
atomic_t nr_client_conns;
- spinlock_t client_conn_cache_lock; /* Lock for ->*_client_conns */
- struct mutex client_conn_discard_lock; /* Prevent multiple discarders */
- struct list_head idle_client_conns;
- struct work_struct client_conn_reaper;
- struct timer_list client_conn_reap_timer;
struct hlist_head local_endpoints;
struct mutex local_mutex; /* Lock for ->local_endpoints */
@@ -294,8 +288,16 @@ struct rxrpc_local {
struct sk_buff_head rx_queue; /* Received packets */
struct list_head conn_attend_q; /* Conns requiring immediate attention */
struct list_head call_attend_q; /* Calls requiring immediate attention */
+
struct rb_root client_bundles; /* Client connection bundles by socket params */
spinlock_t client_bundles_lock; /* Lock for client_bundles */
+ bool kill_all_client_conns;
+ spinlock_t client_conn_cache_lock; /* Lock for ->*_client_conns */
+ struct list_head idle_client_conns;
+ struct timer_list client_conn_reap_timer;
+ unsigned long client_conn_flags;
+#define RXRPC_CLIENT_CONN_REAP_TIMER 0 /* The client conn reap timer expired */
+
spinlock_t lock; /* access lock */
rwlock_t services_lock; /* lock for services list */
int debug_id; /* debug ID for printks */
@@ -939,8 +941,7 @@ void rxrpc_expose_client_call(struct rxrpc_call *);
void rxrpc_disconnect_client_call(struct rxrpc_bundle *, struct rxrpc_call *);
void rxrpc_deactivate_bundle(struct rxrpc_bundle *);
void rxrpc_put_client_conn(struct rxrpc_connection *, enum rxrpc_conn_trace);
-void rxrpc_discard_expired_client_conns(struct work_struct *);
-void rxrpc_destroy_all_client_connections(struct rxrpc_net *);
+void rxrpc_discard_expired_client_conns(struct rxrpc_local *);
void rxrpc_clean_up_local_conns(struct rxrpc_local *);
diff --git a/net/rxrpc/conn_client.c b/net/rxrpc/conn_client.c
index 320cb1233917..0f719177b844 100644
--- a/net/rxrpc/conn_client.c
+++ b/net/rxrpc/conn_client.c
@@ -578,17 +578,17 @@ static void rxrpc_activate_one_channel(struct rxrpc_connection *conn,
*/
static void rxrpc_unidle_conn(struct rxrpc_bundle *bundle, struct rxrpc_connection *conn)
{
- struct rxrpc_net *rxnet = bundle->local->rxnet;
+ struct rxrpc_local *local = bundle->local;
bool drop_ref;
if (!list_empty(&conn->cache_link)) {
drop_ref = false;
- spin_lock(&rxnet->client_conn_cache_lock);
+ spin_lock(&local->client_conn_cache_lock);
if (!list_empty(&conn->cache_link)) {
list_del_init(&conn->cache_link);
drop_ref = true;
}
- spin_unlock(&rxnet->client_conn_cache_lock);
+ spin_unlock(&local->client_conn_cache_lock);
if (drop_ref)
rxrpc_put_connection(conn, rxrpc_conn_put_unidle);
}
@@ -710,14 +710,10 @@ static int rxrpc_wait_for_channel(struct rxrpc_bundle *bundle,
int rxrpc_connect_call(struct rxrpc_call *call, gfp_t gfp)
{
struct rxrpc_bundle *bundle;
- struct rxrpc_local *local = call->local;
- struct rxrpc_net *rxnet = local->rxnet;
int ret = 0;
_enter("{%d,%lx},", call->debug_id, call->user_call_ID);
- rxrpc_discard_expired_client_conns(&rxnet->client_conn_reaper);
-
rxrpc_get_call(call, rxrpc_call_get_io_thread);
bundle = rxrpc_prep_call(call, gfp);
@@ -787,14 +783,14 @@ void rxrpc_expose_client_call(struct rxrpc_call *call)
/*
* Set the reap timer.
*/
-static void rxrpc_set_client_reap_timer(struct rxrpc_net *rxnet)
+static void rxrpc_set_client_reap_timer(struct rxrpc_local *local)
{
- if (!rxnet->kill_all_client_conns) {
+ if (!local->kill_all_client_conns) {
unsigned long now = jiffies;
unsigned long reap_at = now + rxrpc_conn_idle_client_expiry;
- if (rxnet->live)
- timer_reduce(&rxnet->client_conn_reap_timer, reap_at);
+ if (local->rxnet->live)
+ timer_reduce(&local->client_conn_reap_timer, reap_at);
}
}
@@ -805,7 +801,7 @@ void rxrpc_disconnect_client_call(struct rxrpc_bundle *bundle, struct rxrpc_call
{
struct rxrpc_connection *conn;
struct rxrpc_channel *chan = NULL;
- struct rxrpc_net *rxnet = bundle->local->rxnet;
+ struct rxrpc_local *local = bundle->local;
unsigned int channel;
bool may_reuse;
u32 cid;
@@ -895,11 +891,11 @@ void rxrpc_disconnect_client_call(struct rxrpc_bundle *bundle, struct rxrpc_call
conn->idle_timestamp = jiffies;
rxrpc_get_connection(conn, rxrpc_conn_get_idle);
- spin_lock(&rxnet->client_conn_cache_lock);
- list_move_tail(&conn->cache_link, &rxnet->idle_client_conns);
- spin_unlock(&rxnet->client_conn_cache_lock);
+ spin_lock(&local->client_conn_cache_lock);
+ list_move_tail(&conn->cache_link, &local->idle_client_conns);
+ spin_unlock(&local->client_conn_cache_lock);
- rxrpc_set_client_reap_timer(rxnet);
+ rxrpc_set_client_reap_timer(local);
}
out:
@@ -986,42 +982,34 @@ void rxrpc_kill_client_conn(struct rxrpc_connection *conn)
* This may be called from conn setup or from a work item so cannot be
* considered non-reentrant.
*/
-void rxrpc_discard_expired_client_conns(struct work_struct *work)
+void rxrpc_discard_expired_client_conns(struct rxrpc_local *local)
{
struct rxrpc_connection *conn;
- struct rxrpc_net *rxnet =
- container_of(work, struct rxrpc_net, client_conn_reaper);
unsigned long expiry, conn_expires_at, now;
unsigned int nr_conns;
_enter("");
- if (list_empty(&rxnet->idle_client_conns)) {
+ if (list_empty(&local->idle_client_conns)) {
_leave(" [empty]");
return;
}
- /* Don't double up on the discarding */
- if (!mutex_trylock(&rxnet->client_conn_discard_lock)) {
- _leave(" [already]");
- return;
- }
-
/* We keep an estimate of what the number of conns ought to be after
* we've discarded some so that we don't overdo the discarding.
*/
- nr_conns = atomic_read(&rxnet->nr_client_conns);
+ nr_conns = atomic_read(&local->rxnet->nr_client_conns);
next:
- spin_lock(&rxnet->client_conn_cache_lock);
+ spin_lock(&local->client_conn_cache_lock);
- if (list_empty(&rxnet->idle_client_conns))
+ if (list_empty(&local->idle_client_conns))
goto out;
- conn = list_entry(rxnet->idle_client_conns.next,
+ conn = list_entry(local->idle_client_conns.next,
struct rxrpc_connection, cache_link);
- if (!rxnet->kill_all_client_conns) {
+ if (!local->kill_all_client_conns) {
/* If the number of connections is over the reap limit, we
* expedite discard by reducing the expiry timeout. We must,
* however, have at least a short grace period to be able to do
@@ -1044,7 +1032,7 @@ void rxrpc_discard_expired_client_conns(struct work_struct *work)
trace_rxrpc_client(conn, -1, rxrpc_client_discard);
list_del_init(&conn->cache_link);
- spin_unlock(&rxnet->client_conn_cache_lock);
+ spin_unlock(&local->client_conn_cache_lock);
rxrpc_unbundle_conn(conn);
/* Drop the ->cache_link ref */
@@ -1062,32 +1050,11 @@ void rxrpc_discard_expired_client_conns(struct work_struct *work)
* then things get messier.
*/
_debug("not yet");
- if (!rxnet->kill_all_client_conns)
- timer_reduce(&rxnet->client_conn_reap_timer, conn_expires_at);
+ if (!local->kill_all_client_conns)
+ timer_reduce(&local->client_conn_reap_timer, conn_expires_at);
out:
- spin_unlock(&rxnet->client_conn_cache_lock);
- mutex_unlock(&rxnet->client_conn_discard_lock);
- _leave("");
-}
-
-/*
- * Preemptively destroy all the client connection records rather than waiting
- * for them to time out
- */
-void rxrpc_destroy_all_client_connections(struct rxrpc_net *rxnet)
-{
- _enter("");
-
- spin_lock(&rxnet->client_conn_cache_lock);
- rxnet->kill_all_client_conns = true;
- spin_unlock(&rxnet->client_conn_cache_lock);
-
- del_timer_sync(&rxnet->client_conn_reap_timer);
-
- if (!rxrpc_queue_work(&rxnet->client_conn_reaper))
- _debug("destroy: queue failed");
-
+ spin_unlock(&local->client_conn_cache_lock);
_leave("");
}
@@ -1097,14 +1064,19 @@ void rxrpc_destroy_all_client_connections(struct rxrpc_net *rxnet)
void rxrpc_clean_up_local_conns(struct rxrpc_local *local)
{
struct rxrpc_connection *conn, *tmp;
- struct rxrpc_net *rxnet = local->rxnet;
LIST_HEAD(graveyard);
_enter("");
- spin_lock(&rxnet->client_conn_cache_lock);
+ spin_lock(&local->client_conn_cache_lock);
+ local->kill_all_client_conns = true;
+ spin_unlock(&local->client_conn_cache_lock);
+
+ del_timer_sync(&local->client_conn_reap_timer);
+
+ spin_lock(&local->client_conn_cache_lock);
- list_for_each_entry_safe(conn, tmp, &rxnet->idle_client_conns,
+ list_for_each_entry_safe(conn, tmp, &local->idle_client_conns,
cache_link) {
if (conn->local == local) {
atomic_dec(&conn->active);
@@ -1113,7 +1085,7 @@ void rxrpc_clean_up_local_conns(struct rxrpc_local *local)
}
}
- spin_unlock(&rxnet->client_conn_cache_lock);
+ spin_unlock(&local->client_conn_cache_lock);
while (!list_empty(&graveyard)) {
conn = list_entry(graveyard.next,
diff --git a/net/rxrpc/conn_object.c b/net/rxrpc/conn_object.c
index 2ef43ce3dd3c..56ea9316e3ff 100644
--- a/net/rxrpc/conn_object.c
+++ b/net/rxrpc/conn_object.c
@@ -470,7 +470,6 @@ void rxrpc_destroy_all_connections(struct rxrpc_net *rxnet)
_enter("");
atomic_dec(&rxnet->nr_conns);
- rxrpc_destroy_all_client_connections(rxnet);
del_timer_sync(&rxnet->service_conn_reap_timer);
rxrpc_queue_work(&rxnet->service_conn_reaper);
diff --git a/net/rxrpc/io_thread.c b/net/rxrpc/io_thread.c
index e7db137f78e1..89335f5f1a02 100644
--- a/net/rxrpc/io_thread.c
+++ b/net/rxrpc/io_thread.c
@@ -434,6 +434,10 @@ int rxrpc_io_thread(void *data)
continue;
}
+ if (test_and_clear_bit(RXRPC_CLIENT_CONN_REAP_TIMER,
+ &local->client_conn_flags))
+ rxrpc_discard_expired_client_conns(local);
+
/* Deal with calls that want immediate attention. */
if ((call = list_first_entry_or_null(&local->call_attend_q,
struct rxrpc_call,
diff --git a/net/rxrpc/local_object.c b/net/rxrpc/local_object.c
index ca8b3ee68b59..9bc8d08ca12c 100644
--- a/net/rxrpc/local_object.c
+++ b/net/rxrpc/local_object.c
@@ -82,6 +82,16 @@ static long rxrpc_local_cmp_key(const struct rxrpc_local *local,
}
}
+static void rxrpc_client_conn_reap_timeout(struct timer_list *timer)
+{
+ struct rxrpc_local *local =
+ container_of(timer, struct rxrpc_local, client_conn_reap_timer);
+
+ if (local->kill_all_client_conns &&
+ test_and_set_bit(RXRPC_CLIENT_CONN_REAP_TIMER, &local->client_conn_flags))
+ rxrpc_wake_up_io_thread(local);
+}
+
/*
* Allocate a new local endpoint.
*/
@@ -103,8 +113,15 @@ static struct rxrpc_local *rxrpc_alloc_local(struct net *net,
skb_queue_head_init(&local->rx_queue);
INIT_LIST_HEAD(&local->conn_attend_q);
INIT_LIST_HEAD(&local->call_attend_q);
+
local->client_bundles = RB_ROOT;
spin_lock_init(&local->client_bundles_lock);
+ local->kill_all_client_conns = false;
+ spin_lock_init(&local->client_conn_cache_lock);
+ INIT_LIST_HEAD(&local->idle_client_conns);
+ timer_setup(&local->client_conn_reap_timer,
+ rxrpc_client_conn_reap_timeout, 0);
+
spin_lock_init(&local->lock);
rwlock_init(&local->services_lock);
local->debug_id = atomic_inc_return(&rxrpc_debug_id);
diff --git a/net/rxrpc/net_ns.c b/net/rxrpc/net_ns.c
index 5905530e2f33..a0319c040c25 100644
--- a/net/rxrpc/net_ns.c
+++ b/net/rxrpc/net_ns.c
@@ -10,15 +10,6 @@
unsigned int rxrpc_net_id;
-static void rxrpc_client_conn_reap_timeout(struct timer_list *timer)
-{
- struct rxrpc_net *rxnet =
- container_of(timer, struct rxrpc_net, client_conn_reap_timer);
-
- if (rxnet->live)
- rxrpc_queue_work(&rxnet->client_conn_reaper);
-}
-
static void rxrpc_service_conn_reap_timeout(struct timer_list *timer)
{
struct rxrpc_net *rxnet =
@@ -63,14 +54,6 @@ static __net_init int rxrpc_init_net(struct net *net)
rxrpc_service_conn_reap_timeout, 0);
atomic_set(&rxnet->nr_client_conns, 0);
- rxnet->kill_all_client_conns = false;
- spin_lock_init(&rxnet->client_conn_cache_lock);
- mutex_init(&rxnet->client_conn_discard_lock);
- INIT_LIST_HEAD(&rxnet->idle_client_conns);
- INIT_WORK(&rxnet->client_conn_reaper,
- rxrpc_discard_expired_client_conns);
- timer_setup(&rxnet->client_conn_reap_timer,
- rxrpc_client_conn_reap_timeout, 0);
INIT_HLIST_HEAD(&rxnet->local_endpoints);
mutex_init(&rxnet->local_mutex);
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