From 5492390a9495bade807afca61eab860f852e33fa Mon Sep 17 00:00:00 2001 From: Ying Xue Date: Tue, 2 Dec 2014 15:00:28 +0800 Subject: [PATCH] tipc: simplify relationship between name table lock and node lock When tipc name sequence is published, name table lock is released before name sequence buffer is delivered to remote nodes through its underlying unicast links. However, when name sequence is withdrawn, the name table lock is held until the transmission of the removal message of name sequence is finished. During the process, node lock is nested in name table lock. To prevent node lock from being nested in name table lock, while withdrawing name, we should adopt the same locking policy of publishing name sequence: name table lock should be released before message is sent. Signed-off-by: Ying Xue Reviewed-by: Erik Hugne Reviewed-by: Jon Maloy Tested-by: Erik Hugne Signed-off-by: David S. Miller --- net/tipc/name_table.c | 19 ++++++++++--------- 1 file changed, 10 insertions(+), 9 deletions(-) diff --git a/net/tipc/name_table.c b/net/tipc/name_table.c index 93bac40292c1..bc3e7ed80000 100644 --- a/net/tipc/name_table.c +++ b/net/tipc/name_table.c @@ -685,27 +685,28 @@ struct publication *tipc_nametbl_publish(u32 type, u32 lower, u32 upper, int tipc_nametbl_withdraw(u32 type, u32 lower, u32 ref, u32 key) { struct publication *publ; - struct sk_buff *buf; + struct sk_buff *skb = NULL; write_lock_bh(&tipc_nametbl_lock); publ = tipc_nametbl_remove_publ(type, lower, tipc_own_addr, ref, key); if (likely(publ)) { tipc_nametbl->local_publ_count--; - buf = tipc_named_withdraw(publ); + skb = tipc_named_withdraw(publ); /* Any pending external events? */ tipc_named_process_backlog(); - write_unlock_bh(&tipc_nametbl_lock); list_del_init(&publ->pport_list); kfree(publ); + } else { + pr_err("Unable to remove local publication\n" + "(type=%u, lower=%u, ref=%u, key=%u)\n", + type, lower, ref, key); + } + write_unlock_bh(&tipc_nametbl_lock); - if (buf) - named_cluster_distribute(buf); + if (skb) { + named_cluster_distribute(skb); return 1; } - write_unlock_bh(&tipc_nametbl_lock); - pr_err("Unable to remove local publication\n" - "(type=%u, lower=%u, ref=%u, key=%u)\n", - type, lower, ref, key); return 0; } -- 2.20.1