RDS: split out connection specific state from rds_connection to rds_conn_path
In preparation for multipath RDS, split the rds_connection
structure into a base structure, and a per-path struct rds_conn_path.
The base structure tracks information and locks common to all
paths. The workqs for send/recv/shutdown etc are tracked per
rds_conn_path. Thus the workq callbacks now work with rds_conn_path.
This commit allows for one rds_conn_path per rds_connection, and will
be extended into multiple conn_paths in subsequent commits.
Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/rds/rds.h b/net/rds/rds.h
index 387df5f..ca31a07 100644
--- a/net/rds/rds.h
+++ b/net/rds/rds.h
@@ -84,56 +84,69 @@
#define RDS_IN_XMIT 2
#define RDS_RECV_REFILL 3
+/* Max number of multipaths per RDS connection. Must be a power of 2 */
+#define RDS_MPATH_WORKERS 1
+
+/* Per mpath connection state */
+struct rds_conn_path {
+ struct rds_connection *cp_conn;
+ struct rds_message *cp_xmit_rm;
+ unsigned long cp_xmit_sg;
+ unsigned int cp_xmit_hdr_off;
+ unsigned int cp_xmit_data_off;
+ unsigned int cp_xmit_atomic_sent;
+ unsigned int cp_xmit_rdma_sent;
+ unsigned int cp_xmit_data_sent;
+
+ spinlock_t cp_lock; /* protect msg queues */
+ u64 cp_next_tx_seq;
+ struct list_head cp_send_queue;
+ struct list_head cp_retrans;
+
+ u64 cp_next_rx_seq;
+
+ void *cp_transport_data;
+
+ atomic_t cp_state;
+ unsigned long cp_send_gen;
+ unsigned long cp_flags;
+ unsigned long cp_reconnect_jiffies;
+ struct delayed_work cp_send_w;
+ struct delayed_work cp_recv_w;
+ struct delayed_work cp_conn_w;
+ struct work_struct cp_down_w;
+ struct mutex cp_cm_lock; /* protect cp_state & cm */
+ wait_queue_head_t cp_waitq;
+
+ unsigned int cp_unacked_packets;
+ unsigned int cp_unacked_bytes;
+ unsigned int cp_outgoing:1,
+ cp_pad_to_32:31;
+ unsigned int cp_index;
+};
+
+/* One rds_connection per RDS address pair */
struct rds_connection {
struct hlist_node c_hash_node;
__be32 c_laddr;
__be32 c_faddr;
unsigned int c_loopback:1,
- c_outgoing:1,
- c_pad_to_32:30;
+ c_pad_to_32:31;
+ int c_npaths;
struct rds_connection *c_passive;
+ struct rds_transport *c_trans;
struct rds_cong_map *c_lcong;
struct rds_cong_map *c_fcong;
- struct rds_message *c_xmit_rm;
- unsigned long c_xmit_sg;
- unsigned int c_xmit_hdr_off;
- unsigned int c_xmit_data_off;
- unsigned int c_xmit_atomic_sent;
- unsigned int c_xmit_rdma_sent;
- unsigned int c_xmit_data_sent;
-
- spinlock_t c_lock; /* protect msg queues */
- u64 c_next_tx_seq;
- struct list_head c_send_queue;
- struct list_head c_retrans;
-
- u64 c_next_rx_seq;
-
- struct rds_transport *c_trans;
- void *c_transport_data;
-
- atomic_t c_state;
- unsigned long c_send_gen;
- unsigned long c_flags;
- unsigned long c_reconnect_jiffies;
- struct delayed_work c_send_w;
- struct delayed_work c_recv_w;
- struct delayed_work c_conn_w;
- struct work_struct c_down_w;
- struct mutex c_cm_lock; /* protect conn state & cm */
- wait_queue_head_t c_waitq;
+ /* Protocol version */
+ unsigned int c_version;
+ possible_net_t c_net;
struct list_head c_map_item;
unsigned long c_map_queued;
- unsigned int c_unacked_packets;
- unsigned int c_unacked_bytes;
-
- /* Protocol version */
- unsigned int c_version;
- possible_net_t c_net;
+ struct rds_conn_path c_path[RDS_MPATH_WORKERS];
};
static inline
@@ -639,6 +652,7 @@
void rds_conn_shutdown(struct rds_connection *conn);
void rds_conn_destroy(struct rds_connection *conn);
void rds_conn_drop(struct rds_connection *conn);
+void rds_conn_path_drop(struct rds_conn_path *cpath);
void rds_conn_connect_if_down(struct rds_connection *conn);
void rds_for_each_conn_info(struct socket *sock, unsigned int len,
struct rds_info_iterator *iter,
@@ -651,27 +665,51 @@
__rds_conn_error(conn, KERN_WARNING "RDS: " fmt)
static inline int
+rds_conn_path_transition(struct rds_conn_path *cp, int old, int new)
+{
+ return atomic_cmpxchg(&cp->cp_state, old, new) == old;
+}
+
+static inline int
rds_conn_transition(struct rds_connection *conn, int old, int new)
{
- return atomic_cmpxchg(&conn->c_state, old, new) == old;
+ return rds_conn_path_transition(&conn->c_path[0], old, new);
+}
+
+static inline int
+rds_conn_path_state(struct rds_conn_path *cp)
+{
+ return atomic_read(&cp->cp_state);
}
static inline int
rds_conn_state(struct rds_connection *conn)
{
- return atomic_read(&conn->c_state);
+ return rds_conn_path_state(&conn->c_path[0]);
+}
+
+static inline int
+rds_conn_path_up(struct rds_conn_path *cp)
+{
+ return atomic_read(&cp->cp_state) == RDS_CONN_UP;
}
static inline int
rds_conn_up(struct rds_connection *conn)
{
- return atomic_read(&conn->c_state) == RDS_CONN_UP;
+ return rds_conn_path_up(&conn->c_path[0]);
+}
+
+static inline int
+rds_conn_path_connecting(struct rds_conn_path *cp)
+{
+ return atomic_read(&cp->cp_state) == RDS_CONN_CONNECTING;
}
static inline int
rds_conn_connecting(struct rds_connection *conn)
{
- return atomic_read(&conn->c_state) == RDS_CONN_CONNECTING;
+ return rds_conn_path_connecting(&conn->c_path[0]);
}
/* message.c */
@@ -809,12 +847,12 @@
int rds_threads_init(void);
void rds_threads_exit(void);
extern struct workqueue_struct *rds_wq;
-void rds_queue_reconnect(struct rds_connection *conn);
+void rds_queue_reconnect(struct rds_conn_path *cp);
void rds_connect_worker(struct work_struct *);
void rds_shutdown_worker(struct work_struct *);
void rds_send_worker(struct work_struct *);
void rds_recv_worker(struct work_struct *);
-void rds_connect_path_complete(struct rds_connection *conn, int curr);
+void rds_connect_path_complete(struct rds_conn_path *conn, int curr);
void rds_connect_complete(struct rds_connection *conn);
/* transport.c */