rds: Use RCU for the bind lookup searches
The RDS bind lookups are somewhat expensive in terms of CPU
time and locking overhead. This commit changes them into a
faster RCU based hash tree instead of the rbtrees they were using
before.
On large NUMA systems it is a significant improvement.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/net/rds/af_rds.c b/net/rds/af_rds.c
index ef09340..f16d2a9 100644
--- a/net/rds/af_rds.c
+++ b/net/rds/af_rds.c
@@ -72,7 +72,15 @@
* with the socket. */
rds_clear_recv_queue(rs);
rds_cong_remove_socket(rs);
+
+ /*
+ * the binding lookup hash uses rcu, we need to
+ * make sure we sychronize_rcu before we free our
+ * entry
+ */
rds_remove_bound(rs);
+ synchronize_rcu();
+
rds_send_drop_to(rs, NULL);
rds_rdma_drop_keys(rs);
rds_notify_queue_get(rs, NULL);