From 8b0a6b461e2ccc95363e0547aa4f43ba2e02b096 Mon Sep 17 00:00:00 2001 From: Santosh Shilimkar Date: Fri, 3 Feb 2012 11:09:23 -0500 Subject: RDS: make socket bind/release locking scheme simple and more efficient RDS bind and release locking scheme is very inefficient. It uses RCU for maintaining the bind hash-table which is great but it also needs to hold spinlock for [add/remove]_bound(). So overall usecase, the hash-table concurrent speedup doesn't pay off. In fact blocking nature of synchronize_rcu() makes the RDS socket shutdown too slow which hurts RDS performance since connection shutdown and re-connect happens quite often to maintain the RC part of the protocol. So we make the locking scheme simpler and more efficient by replacing spin_locks with reader/writer locks and getting rid off rcu for bind hash-table. In subsequent patch, we also covert the global lock with per-bucket lock to reduce the global lock contention. Signed-off-by: Santosh Shilimkar Signed-off-by: Santosh Shilimkar --- net/rds/af_rds.c | 6 ------ 1 file changed, 6 deletions(-) (limited to 'net/rds/af_rds.c') diff --git a/net/rds/af_rds.c b/net/rds/af_rds.c index a2f28a6d4dc5..dc087666217a 100644 --- a/net/rds/af_rds.c +++ b/net/rds/af_rds.c @@ -72,13 +72,7 @@ static int rds_release(struct socket *sock) rds_clear_recv_queue(rs); rds_cong_remove_socket(rs); - /* - * the binding lookup hash uses rcu, we need to - * make sure we synchronize_rcu before we free our - * entry - */ rds_remove_bound(rs); - synchronize_rcu(); rds_send_drop_to(rs, NULL); rds_rdma_drop_keys(rs); -- cgit v1.2.3