diff options
| -rw-r--r-- | net/rds/send.c | 30 |
1 files changed, 15 insertions, 15 deletions
diff --git a/net/rds/send.c b/net/rds/send.c index ecda3e6c432..656c5c1b32b 100644 --- a/net/rds/send.c +++ b/net/rds/send.c @@ -110,12 +110,11 @@ int rds_send_xmit(struct rds_connection *conn) struct rds_message *rm; unsigned long flags; unsigned int tmp; - unsigned int send_quota = send_batch_count; struct scatterlist *sg; int ret = 0; - int was_empty = 0; LIST_HEAD(to_be_dropped); +restart: if (!rds_conn_up(conn)) goto out; @@ -139,7 +138,7 @@ int rds_send_xmit(struct rds_connection *conn) * spin trying to push headers and data down the connection until * the connection doesn't make forward progress. */ - while (--send_quota) { + while (1) { rm = conn->c_xmit_rm; @@ -185,10 +184,8 @@ int rds_send_xmit(struct rds_connection *conn) spin_unlock(&conn->c_lock); - if (!rm) { - was_empty = 1; + if (!rm) break; - } /* Unfortunately, the way Infiniband deals with * RDMA to a bad MR key is by moving the entire @@ -350,20 +347,23 @@ int rds_send_xmit(struct rds_connection *conn) rds_send_remove_from_sock(&to_be_dropped, RDS_RDMA_DROPPED); } - if (send_quota == 0 && !was_empty) { - /* We exhausted the send quota, but there's work left to - * do. Return and (re-)schedule the send worker. - */ - ret = -EAGAIN; - } - - if (ret == 0 && was_empty) { + /* + * Other senders will see we have c_send_lock and exit. We + * need to recheck the send queue and race again for c_send_lock + * to make sure messages don't just sit on the send queue. + * + * If the transport cannot continue (i.e ret != 0), then it must + * call us when more room is available, such as from the tx + * completion handler. + */ + if (ret == 0) { /* A simple bit test would be way faster than taking the * spin lock */ spin_lock_irqsave(&conn->c_lock, flags); if (!list_empty(&conn->c_send_queue)) { rds_stats_inc(s_send_lock_queue_raced); - ret = -EAGAIN; + spin_unlock_irqrestore(&conn->c_lock, flags); + goto restart; } spin_unlock_irqrestore(&conn->c_lock, flags); } |