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Diffstat (limited to 'net/rds')
-rw-r--r--net/rds/send.c30
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);
}