bool kill_all_client_conns;
atomic_t nr_client_conns;
spinlock_t client_conn_cache_lock; /* Lock for ->*_client_conns */
- spinlock_t client_conn_discard_lock; /* Prevent multiple discarders */
+ 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 rxrpc_conn_proto proto;
struct rxrpc_local *local; /* Representation of local endpoint */
struct rxrpc_peer *peer; /* Remote endpoint */
+ struct rxrpc_net *rxnet; /* Network namespace to which call belongs */
struct key *key; /* Security details */
refcount_t ref;
+ atomic_t active; /* Active count for service conns */
struct rcu_head rcu;
struct list_head cache_link;
struct timer_list timer; /* Conn event timer */
struct work_struct processor; /* connection event processor */
+ struct work_struct destructor; /* In-process-context destroyer */
struct rxrpc_bundle *bundle; /* Client connection bundle */
struct rb_node service_node; /* Node in peer->service_conns */
struct list_head proc_link; /* link in procfs list */
extern unsigned int rxrpc_connection_expiry;
extern unsigned int rxrpc_closed_conn_expiry;
-struct rxrpc_connection *rxrpc_alloc_connection(gfp_t);
+struct rxrpc_connection *rxrpc_alloc_connection(struct rxrpc_net *, gfp_t);
struct rxrpc_connection *rxrpc_find_connection_rcu(struct rxrpc_local *,
struct sk_buff *,
struct rxrpc_peer **);
void __rxrpc_disconnect_call(struct rxrpc_connection *, struct rxrpc_call *);
void rxrpc_disconnect_call(struct rxrpc_call *);
-void rxrpc_kill_connection(struct rxrpc_connection *);
-bool rxrpc_queue_conn(struct rxrpc_connection *, enum rxrpc_conn_trace);
+void rxrpc_kill_client_conn(struct rxrpc_connection *);
+void rxrpc_queue_conn(struct rxrpc_connection *, enum rxrpc_conn_trace);
void rxrpc_see_connection(struct rxrpc_connection *, enum rxrpc_conn_trace);
struct rxrpc_connection *rxrpc_get_connection(struct rxrpc_connection *,
enum rxrpc_conn_trace);
struct rxrpc_connection *rxrpc_get_connection_maybe(struct rxrpc_connection *,
enum rxrpc_conn_trace);
-void rxrpc_put_service_conn(struct rxrpc_connection *, enum rxrpc_conn_trace);
+void rxrpc_put_connection(struct rxrpc_connection *, enum rxrpc_conn_trace);
void rxrpc_service_connection_reaper(struct work_struct *);
void rxrpc_destroy_all_connections(struct rxrpc_net *);
return !rxrpc_conn_is_client(conn);
}
-static inline void rxrpc_put_connection(struct rxrpc_connection *conn,
- enum rxrpc_conn_trace why)
-{
- if (!conn)
- return;
-
- if (rxrpc_conn_is_client(conn))
- rxrpc_put_client_conn(conn, why);
- else
- rxrpc_put_service_conn(conn, why);
-}
-
static inline void rxrpc_reduce_conn_timer(struct rxrpc_connection *conn,
unsigned long expire_at)
{
static int rxrpc_get_client_connection_id(struct rxrpc_connection *conn,
gfp_t gfp)
{
- struct rxrpc_net *rxnet = conn->local->rxnet;
+ struct rxrpc_net *rxnet = conn->rxnet;
int id;
_enter("");
_enter("");
- conn = rxrpc_alloc_connection(gfp);
+ conn = rxrpc_alloc_connection(rxnet, gfp);
if (!conn) {
_leave(" = -ENOMEM");
return ERR_PTR(-ENOMEM);
if (!conn)
goto dont_reuse;
- rxnet = conn->local->rxnet;
+ rxnet = conn->rxnet;
if (test_bit(RXRPC_CONN_DONT_REUSE, &conn->flags))
goto dont_reuse;
/*
* Clean up a dead client connection.
*/
-static void rxrpc_kill_client_conn(struct rxrpc_connection *conn)
+void rxrpc_kill_client_conn(struct rxrpc_connection *conn)
{
struct rxrpc_local *local = conn->local;
struct rxrpc_net *rxnet = local->rxnet;
atomic_dec(&rxnet->nr_client_conns);
rxrpc_put_client_connection_id(conn);
- rxrpc_kill_connection(conn);
-}
-
-/*
- * Clean up a dead client connections.
- */
-void rxrpc_put_client_conn(struct rxrpc_connection *conn,
- enum rxrpc_conn_trace why)
-{
- unsigned int debug_id = conn->debug_id;
- bool dead;
- int r;
-
- dead = __refcount_dec_and_test(&conn->ref, &r);
- trace_rxrpc_conn(debug_id, r - 1, why);
- if (dead)
- rxrpc_kill_client_conn(conn);
}
/*
}
/* Don't double up on the discarding */
- if (!spin_trylock(&rxnet->client_conn_discard_lock)) {
+ if (!mutex_trylock(&rxnet->client_conn_discard_lock)) {
_leave(" [already]");
return;
}
goto not_yet_expired;
}
+ atomic_dec(&conn->active);
trace_rxrpc_client(conn, -1, rxrpc_client_discard);
list_del_init(&conn->cache_link);
out:
spin_unlock(&rxnet->client_conn_cache_lock);
- spin_unlock(&rxnet->client_conn_discard_lock);
+ mutex_unlock(&rxnet->client_conn_discard_lock);
_leave("");
}
list_for_each_entry_safe(conn, tmp, &rxnet->idle_client_conns,
cache_link) {
if (conn->local == local) {
+ atomic_dec(&conn->active);
trace_rxrpc_client(conn, -1, rxrpc_client_discard);
list_move(&conn->cache_link, &graveyard);
}
unsigned int __read_mostly rxrpc_connection_expiry = 10 * 60;
unsigned int __read_mostly rxrpc_closed_conn_expiry = 10;
-static void rxrpc_destroy_connection(struct rcu_head *);
+static void rxrpc_clean_up_connection(struct work_struct *work);
+static void rxrpc_set_service_reap_timer(struct rxrpc_net *rxnet,
+ unsigned long reap_at);
static void rxrpc_connection_timer(struct timer_list *timer)
{
/*
* allocate a new connection
*/
-struct rxrpc_connection *rxrpc_alloc_connection(gfp_t gfp)
+struct rxrpc_connection *rxrpc_alloc_connection(struct rxrpc_net *rxnet,
+ gfp_t gfp)
{
struct rxrpc_connection *conn;
if (conn) {
INIT_LIST_HEAD(&conn->cache_link);
timer_setup(&conn->timer, &rxrpc_connection_timer, 0);
- INIT_WORK(&conn->processor, &rxrpc_process_connection);
+ INIT_WORK(&conn->processor, rxrpc_process_connection);
+ INIT_WORK(&conn->destructor, rxrpc_clean_up_connection);
INIT_LIST_HEAD(&conn->proc_link);
INIT_LIST_HEAD(&conn->link);
skb_queue_head_init(&conn->rx_queue);
+ conn->rxnet = rxnet;
conn->security = &rxrpc_no_security;
spin_lock_init(&conn->state_lock);
conn->debug_id = atomic_inc_return(&rxrpc_debug_id);
set_bit(RXRPC_CALL_DISCONNECTED, &call->flags);
conn->idle_timestamp = jiffies;
-}
-
-/*
- * Kill off a connection.
- */
-void rxrpc_kill_connection(struct rxrpc_connection *conn)
-{
- struct rxrpc_net *rxnet = conn->local->rxnet;
-
- ASSERT(!rcu_access_pointer(conn->channels[0].call) &&
- !rcu_access_pointer(conn->channels[1].call) &&
- !rcu_access_pointer(conn->channels[2].call) &&
- !rcu_access_pointer(conn->channels[3].call));
- ASSERT(list_empty(&conn->cache_link));
-
- write_lock(&rxnet->conn_lock);
- list_del_init(&conn->proc_link);
- write_unlock(&rxnet->conn_lock);
-
- /* Drain the Rx queue. Note that even though we've unpublished, an
- * incoming packet could still be being added to our Rx queue, so we
- * will need to drain it again in the RCU cleanup handler.
- */
- rxrpc_purge_queue(&conn->rx_queue);
-
- /* Leave final destruction to RCU. The connection processor work item
- * must carry a ref on the connection to prevent us getting here whilst
- * it is queued or running.
- */
- call_rcu(&conn->rcu, rxrpc_destroy_connection);
+ if (atomic_dec_and_test(&conn->active))
+ rxrpc_set_service_reap_timer(conn->rxnet,
+ jiffies + rxrpc_connection_expiry);
}
/*
* Queue a connection's work processor, getting a ref to pass to the work
* queue.
*/
-bool rxrpc_queue_conn(struct rxrpc_connection *conn, enum rxrpc_conn_trace why)
+void rxrpc_queue_conn(struct rxrpc_connection *conn, enum rxrpc_conn_trace why)
{
- int r;
-
- if (!__refcount_inc_not_zero(&conn->ref, &r))
- return false;
- if (rxrpc_queue_work(&conn->processor))
- trace_rxrpc_conn(conn->debug_id, why, r + 1);
- else
- rxrpc_put_connection(conn, rxrpc_conn_put_already_queued);
- return true;
+ if (atomic_read(&conn->active) >= 0 &&
+ rxrpc_queue_work(&conn->processor))
+ rxrpc_see_connection(conn, why);
}
/*
timer_reduce(&rxnet->service_conn_reap_timer, reap_at);
}
-/*
- * Release a service connection
- */
-void rxrpc_put_service_conn(struct rxrpc_connection *conn,
- enum rxrpc_conn_trace why)
-{
- unsigned int debug_id = conn->debug_id;
- int r;
-
- __refcount_dec(&conn->ref, &r);
- trace_rxrpc_conn(debug_id, r - 1, why);
- if (r - 1 == 1)
- rxrpc_set_service_reap_timer(conn->local->rxnet,
- jiffies + rxrpc_connection_expiry);
-}
-
/*
* destroy a virtual connection
*/
-static void rxrpc_destroy_connection(struct rcu_head *rcu)
+static void rxrpc_rcu_free_connection(struct rcu_head *rcu)
{
struct rxrpc_connection *conn =
container_of(rcu, struct rxrpc_connection, rcu);
+ struct rxrpc_net *rxnet = conn->rxnet;
_enter("{%d,u=%d}", conn->debug_id, refcount_read(&conn->ref));
trace_rxrpc_conn(conn->debug_id, refcount_read(&conn->ref),
rxrpc_conn_free);
+ kfree(conn);
- ASSERTCMP(refcount_read(&conn->ref), ==, 0);
+ if (atomic_dec_and_test(&rxnet->nr_conns))
+ wake_up_var(&rxnet->nr_conns);
+}
+
+/*
+ * Clean up a dead connection.
+ */
+static void rxrpc_clean_up_connection(struct work_struct *work)
+{
+ struct rxrpc_connection *conn =
+ container_of(work, struct rxrpc_connection, destructor);
+ struct rxrpc_net *rxnet = conn->rxnet;
+
+ ASSERT(!rcu_access_pointer(conn->channels[0].call) &&
+ !rcu_access_pointer(conn->channels[1].call) &&
+ !rcu_access_pointer(conn->channels[2].call) &&
+ !rcu_access_pointer(conn->channels[3].call));
+ ASSERT(list_empty(&conn->cache_link));
del_timer_sync(&conn->timer);
+ cancel_work_sync(&conn->processor); /* Processing may restart the timer */
+ del_timer_sync(&conn->timer);
+
+ write_lock(&rxnet->conn_lock);
+ list_del_init(&conn->proc_link);
+ write_unlock(&rxnet->conn_lock);
+
rxrpc_purge_queue(&conn->rx_queue);
+ rxrpc_kill_client_conn(conn);
+
conn->security->clear(conn);
key_put(conn->key);
rxrpc_put_bundle(conn->bundle, rxrpc_bundle_put_conn);
rxrpc_put_peer(conn->peer, rxrpc_peer_put_conn);
-
- if (atomic_dec_and_test(&conn->local->rxnet->nr_conns))
- wake_up_var(&conn->local->rxnet->nr_conns);
rxrpc_put_local(conn->local, rxrpc_local_put_kill_conn);
- kfree(conn);
- _leave("");
+ /* Drain the Rx queue. Note that even though we've unpublished, an
+ * incoming packet could still be being added to our Rx queue, so we
+ * will need to drain it again in the RCU cleanup handler.
+ */
+ rxrpc_purge_queue(&conn->rx_queue);
+
+ call_rcu(&conn->rcu, rxrpc_rcu_free_connection);
+}
+
+/*
+ * Drop a ref on a connection.
+ */
+void rxrpc_put_connection(struct rxrpc_connection *conn,
+ enum rxrpc_conn_trace why)
+{
+ unsigned int debug_id;
+ bool dead;
+ int r;
+
+ if (!conn)
+ return;
+
+ debug_id = conn->debug_id;
+ dead = __refcount_dec_and_test(&conn->ref, &r);
+ trace_rxrpc_conn(debug_id, r - 1, why);
+ if (dead) {
+ del_timer(&conn->timer);
+ cancel_work(&conn->processor);
+
+ if (in_softirq() || work_busy(&conn->processor) ||
+ timer_pending(&conn->timer))
+ /* Can't use the rxrpc workqueue as we need to cancel/flush
+ * something that may be running/waiting there.
+ */
+ schedule_work(&conn->destructor);
+ else
+ rxrpc_clean_up_connection(&conn->destructor);
+ }
}
/*
struct rxrpc_net *rxnet =
container_of(work, struct rxrpc_net, service_conn_reaper);
unsigned long expire_at, earliest, idle_timestamp, now;
+ int active;
LIST_HEAD(graveyard);
write_lock(&rxnet->conn_lock);
list_for_each_entry_safe(conn, _p, &rxnet->service_conns, link) {
- ASSERTCMP(refcount_read(&conn->ref), >, 0);
- if (likely(refcount_read(&conn->ref) > 1))
+ ASSERTCMP(atomic_read(&conn->active), >=, 0);
+ if (likely(atomic_read(&conn->active) > 0))
continue;
if (conn->state == RXRPC_CONN_SERVICE_PREALLOC)
continue;
if (conn->local->service_closed)
expire_at = idle_timestamp + rxrpc_closed_conn_expiry * HZ;
- _debug("reap CONN %d { u=%d,t=%ld }",
- conn->debug_id, refcount_read(&conn->ref),
+ _debug("reap CONN %d { a=%d,t=%ld }",
+ conn->debug_id, atomic_read(&conn->active),
(long)expire_at - (long)now);
if (time_before(now, expire_at)) {
}
}
- /* The usage count sits at 1 whilst the object is unused on the
- * list; we reduce that to 0 to make the object unavailable.
+ /* The activity count sits at 0 whilst the conn is unused on
+ * the list; we reduce that to -1 to make the conn unavailable.
*/
- if (!refcount_dec_if_one(&conn->ref))
+ active = 0;
+ if (!atomic_try_cmpxchg(&conn->active, &active, -1))
continue;
rxrpc_see_connection(conn, rxrpc_conn_see_reap_service);
link);
list_del_init(&conn->link);
- ASSERTCMP(refcount_read(&conn->ref), ==, 0);
- rxrpc_kill_connection(conn);
+ ASSERTCMP(atomic_read(&conn->active), ==, -1);
+ rxrpc_put_connection(conn, rxrpc_conn_put_service_reaped);
}
_leave("");
projects / linux.git / commitdiff