struct work_struct rwork; /* Receive workqueue */
struct work_struct swork; /* Send workqueue */
wait_queue_head_t shutdown_wait; /* wait for graceful shutdown */
+ struct rcu_head rcu;
};
#define sock2con(x) ((struct connection *)(x)->sk_user_data)
static struct workqueue_struct *send_workqueue;
static struct hlist_head connection_hash[CONN_HASH_SIZE];
-static DEFINE_MUTEX(connections_lock);
-static struct kmem_cache *con_cache;
+static DEFINE_SPINLOCK(connections_lock);
+DEFINE_STATIC_SRCU(connections_srcu);
static void process_recv_sockets(struct work_struct *work);
static void process_send_sockets(struct work_struct *work);
static struct connection *__find_con(int nodeid)
{
- int r;
+ int r, idx;
struct connection *con;
r = nodeid_hash(nodeid);
- hlist_for_each_entry(con, &connection_hash[r], list) {
- if (con->nodeid == nodeid)
+ idx = srcu_read_lock(&connections_srcu);
+ hlist_for_each_entry_rcu(con, &connection_hash[r], list) {
+ if (con->nodeid == nodeid) {
+ srcu_read_unlock(&connections_srcu, idx);
return con;
+ }
}
+ srcu_read_unlock(&connections_srcu, idx);
+
return NULL;
}
* If 'allocation' is zero then we don't attempt to create a new
* connection structure for this node.
*/
-static struct connection *__nodeid2con(int nodeid, gfp_t alloc)
+static struct connection *nodeid2con(int nodeid, gfp_t alloc)
{
struct connection *con = NULL;
int r;
if (con || !alloc)
return con;
- con = kmem_cache_zalloc(con_cache, alloc);
+ con = kzalloc(sizeof(*con), alloc);
if (!con)
return NULL;
- r = nodeid_hash(nodeid);
- hlist_add_head(&con->list, &connection_hash[r]);
-
con->nodeid = nodeid;
mutex_init(&con->sock_mutex);
INIT_LIST_HEAD(&con->writequeue);
con->rx_action = zerocon->rx_action;
}
+ r = nodeid_hash(nodeid);
+
+ spin_lock(&connections_lock);
+ hlist_add_head_rcu(&con->list, &connection_hash[r]);
+ spin_unlock(&connections_lock);
+
return con;
}
/* Loop round all connections */
static void foreach_conn(void (*conn_func)(struct connection *c))
{
- int i;
- struct hlist_node *n;
+ int i, idx;
struct connection *con;
+ idx = srcu_read_lock(&connections_srcu);
for (i = 0; i < CONN_HASH_SIZE; i++) {
- hlist_for_each_entry_safe(con, n, &connection_hash[i], list)
+ hlist_for_each_entry_rcu(con, &connection_hash[i], list)
conn_func(con);
}
-}
-
-static struct connection *nodeid2con(int nodeid, gfp_t allocation)
-{
- struct connection *con;
-
- mutex_lock(&connections_lock);
- con = __nodeid2con(nodeid, allocation);
- mutex_unlock(&connections_lock);
-
- return con;
+ srcu_read_unlock(&connections_srcu, idx);
}
static struct dlm_node_addr *find_node_addr(int nodeid)
struct connection *newcon;
struct connection *addcon;
- mutex_lock(&connections_lock);
if (!dlm_allow_conn) {
- mutex_unlock(&connections_lock);
return -1;
}
- mutex_unlock(&connections_lock);
mutex_lock_nested(&con->sock_mutex, 0);
struct connection *othercon = newcon->othercon;
if (!othercon) {
- othercon = kmem_cache_zalloc(con_cache, GFP_NOFS);
+ othercon = kzalloc(sizeof(*othercon), GFP_NOFS);
if (!othercon) {
log_print("failed to allocate incoming socket");
mutex_unlock(&newcon->sock_mutex);
{
close_connection(con, true, true, true);
if (con->othercon)
- kmem_cache_free(con_cache, con->othercon);
- hlist_del(&con->list);
- kmem_cache_free(con_cache, con);
+ kfree_rcu(con->othercon, rcu);
+ spin_lock(&connections_lock);
+ hlist_del_rcu(&con->list);
+ spin_unlock(&connections_lock);
+ kfree_rcu(con, rcu);
}
static void work_flush(void)
{
- int ok;
+ int ok, idx;
int i;
- struct hlist_node *n;
struct connection *con;
do {
flush_workqueue(recv_workqueue);
if (send_workqueue)
flush_workqueue(send_workqueue);
+ idx = srcu_read_lock(&connections_srcu);
for (i = 0; i < CONN_HASH_SIZE && ok; i++) {
- hlist_for_each_entry_safe(con, n,
- &connection_hash[i], list) {
+ hlist_for_each_entry_rcu(con, &connection_hash[i],
+ list) {
ok &= test_bit(CF_READ_PENDING, &con->flags);
ok &= test_bit(CF_WRITE_PENDING, &con->flags);
if (con->othercon) {
}
}
}
+ srcu_read_unlock(&connections_srcu, idx);
} while (!ok);
}
/* Set all the flags to prevent any
socket activity.
*/
- mutex_lock(&connections_lock);
dlm_allow_conn = 0;
- mutex_unlock(&connections_lock);
if (recv_workqueue)
flush_workqueue(recv_workqueue);
clean_writequeues();
foreach_conn(free_conn);
work_stop();
-
- kmem_cache_destroy(con_cache);
}
int dlm_lowcomms_start(void)
goto fail;
}
- error = -ENOMEM;
- con_cache = kmem_cache_create("dlm_conn", sizeof(struct connection),
- __alignof__(struct connection), 0,
- NULL);
- if (!con_cache)
- goto fail;
-
error = work_start();
if (error)
- goto fail_destroy;
+ goto fail;
dlm_allow_conn = 1;
con = nodeid2con(0,0);
if (con) {
close_connection(con, false, true, true);
- kmem_cache_free(con_cache, con);
+ kfree_rcu(con, rcu);
}
-fail_destroy:
- kmem_cache_destroy(con_cache);
fail:
return error;
}