Commit cb24405e authored by Andy Grover's avatar Andy Grover Committed by David S. Miller
Browse files

RDS: Refactor end of __conn_create for readability



Add a comment for what's going on. Remove negative logic.
I find this much easier to understand quickly, although
there are a few lines duplicated.
Signed-off-by: default avatarAndy Grover <andy.grover@oracle.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent ed9e352a
......@@ -126,7 +126,7 @@ static struct rds_connection *__rds_conn_create(__be32 laddr, __be32 faddr,
struct rds_transport *trans, gfp_t gfp,
int is_outgoing)
{
struct rds_connection *conn, *tmp, *parent = NULL;
struct rds_connection *conn, *parent = NULL;
struct hlist_head *head = rds_conn_bucket(laddr, faddr);
unsigned long flags;
int ret;
......@@ -210,26 +210,40 @@ static struct rds_connection *__rds_conn_create(__be32 laddr, __be32 faddr,
trans->t_name ? trans->t_name : "[unknown]",
is_outgoing ? "(outgoing)" : "");
/*
* Since we ran without holding the conn lock, someone could
* have created the same conn (either normal or passive) in the
* interim. We check while holding the lock. If we won, we complete
* init and return our conn. If we lost, we rollback and return the
* other one.
*/
spin_lock_irqsave(&rds_conn_lock, flags);
if (parent == NULL) {
tmp = rds_conn_lookup(head, laddr, faddr, trans);
if (tmp == NULL)
hlist_add_head(&conn->c_hash_node, head);
} else {
tmp = parent->c_passive;
if (!tmp)
if (parent) {
/* Creating passive conn */
if (parent->c_passive) {
trans->conn_free(conn->c_transport_data);
kmem_cache_free(rds_conn_slab, conn);
conn = parent->c_passive;
} else {
parent->c_passive = conn;
}
if (tmp) {
trans->conn_free(conn->c_transport_data);
kmem_cache_free(rds_conn_slab, conn);
conn = tmp;
rds_cong_add_conn(conn);
rds_conn_count++;
}
} else {
rds_cong_add_conn(conn);
rds_conn_count++;
/* Creating normal conn */
struct rds_connection *found;
found = rds_conn_lookup(head, laddr, faddr, trans);
if (found) {
trans->conn_free(conn->c_transport_data);
kmem_cache_free(rds_conn_slab, conn);
conn = found;
} else {
hlist_add_head(&conn->c_hash_node, head);
rds_cong_add_conn(conn);
rds_conn_count++;
}
}
spin_unlock_irqrestore(&rds_conn_lock, flags);
out:
......
Markdown is supported
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment