From 7216cd949c9bd56a4ccd952c624ab68f8c9aa0a4 Mon Sep 17 00:00:00 2001 From: Ying Xue Date: Mon, 21 Apr 2014 10:55:48 +0800 Subject: tipc: purge tipc_net_lock lock Now tipc routing hierarchy comprises the structures 'node', 'link'and 'bearer'. The whole hierarchy is protected by a big read/write lock, tipc_net_lock, to ensure that nothing is added or removed while code is accessing any of these structures. Obviously the locking policy makes node, link and bearer components closely bound together so that their relationship becomes unnecessarily complex. In the worst case, such locking policy not only has a negative influence on performance, but also it's prone to lead to deadlock occasionally. In order o decouple the complex relationship between bearer and node as well as link, the locking policy is adjusted as follows: - Bearer level RTNL lock is used on update side, and RCU is used on read side. Meanwhile, all bearer instances including broadcast bearer are saved into bearer_list array. - Node and link level All node instances are saved into two tipc_node_list and node_htable lists. The two lists are protected by node_list_lock on write side, and they are guarded with RCU lock on read side. All members in node structure including link instances are protected by node spin lock. - The relationship between bearer and node When link accesses bearer, it first needs to find the bearer with its bearer identity from the bearer_list array. When bearer accesses node, it can iterate the node_htable hash list with the node address to find the corresponding node. In the new locking policy, every component has its private locking solution and the relationship between bearer and node is very simple, that is, they can find each other with node address or bearer identity from node_htable hash list or bearer_list array. Until now above all changes have been done, so tipc_net_lock can be removed safely. Signed-off-by: Ying Xue Reviewed-by: Jon Maloy Reviewed-by: Erik Hugne Tested-by: Erik Hugne Signed-off-by: David S. Miller --- net/tipc/net.h | 2 -- 1 file changed, 2 deletions(-) (limited to 'net/tipc/net.h') diff --git a/net/tipc/net.h b/net/tipc/net.h index 079daadb3f7..f781cae8df4 100644 --- a/net/tipc/net.h +++ b/net/tipc/net.h @@ -37,8 +37,6 @@ #ifndef _TIPC_NET_H #define _TIPC_NET_H -extern rwlock_t tipc_net_lock; - void tipc_net_route_msg(struct sk_buff *buf); void tipc_net_start(u32 addr); -- cgit v1.2.3-70-g09d2 From eb8b00f5f248c50603bca383792ac3a618297be0 Mon Sep 17 00:00:00 2001 From: Ying Xue Date: Mon, 5 May 2014 08:56:16 +0800 Subject: tipc: convert allocations of global variables associated with bclink Convert allocations of global variables associated with bclink from static way to dynamical way for the convenience of bclink instance initialisation. Meanwhile, this also helps TIPC support name space in the future easily. Signed-off-by: Ying Xue Reviewed-by: Erik Hugne Reviewed-by: Jon Maloy Signed-off-by: David S. Miller --- net/tipc/bcast.c | 28 +++++++++++++++++++--------- net/tipc/bcast.h | 2 +- net/tipc/config.c | 6 ++++-- net/tipc/net.c | 9 +++++++-- net/tipc/net.h | 2 +- 5 files changed, 32 insertions(+), 15 deletions(-) (limited to 'net/tipc/net.h') diff --git a/net/tipc/bcast.c b/net/tipc/bcast.c index 9eceaa72f21..ef8cff4ad74 100644 --- a/net/tipc/bcast.c +++ b/net/tipc/bcast.c @@ -100,12 +100,9 @@ struct tipc_bclink { struct tipc_node *retransmit_to; }; -static struct tipc_bcbearer bcast_bearer; -static struct tipc_bclink bcast_link; - -static struct tipc_bcbearer *bcbearer = &bcast_bearer; -static struct tipc_bclink *bclink = &bcast_link; -static struct tipc_link *bcl = &bcast_link.link; +static struct tipc_bcbearer *bcbearer; +static struct tipc_bclink *bclink; +static struct tipc_link *bcl; const char tipc_bclink_name[] = "broadcast-link"; @@ -788,8 +785,19 @@ int tipc_bclink_set_queue_limits(u32 limit) return 0; } -void tipc_bclink_init(void) +int tipc_bclink_init(void) { + bcbearer = kzalloc(sizeof(*bcbearer), GFP_ATOMIC); + if (!bcbearer) + return -ENOMEM; + + bclink = kzalloc(sizeof(*bclink), GFP_ATOMIC); + if (!bclink) { + kfree(bcbearer); + return -ENOMEM; + } + + bcl = &bclink->link; bcbearer->bearer.media = &bcbearer->media; bcbearer->media.send_msg = tipc_bcbearer_send; sprintf(bcbearer->media.name, "tipc-broadcast"); @@ -805,6 +813,7 @@ void tipc_bclink_init(void) rcu_assign_pointer(bearer_list[MAX_BEARERS], &bcbearer->bearer); bcl->state = WORKING_WORKING; strlcpy(bcl->name, tipc_bclink_name, TIPC_MAX_LINK_NAME); + return 0; } void tipc_bclink_stop(void) @@ -814,8 +823,9 @@ void tipc_bclink_stop(void) tipc_bclink_unlock(); RCU_INIT_POINTER(bearer_list[BCBEARER], NULL); - memset(bclink, 0, sizeof(*bclink)); - memset(bcbearer, 0, sizeof(*bcbearer)); + synchronize_net(); + kfree(bcbearer); + kfree(bclink); } /** diff --git a/net/tipc/bcast.h b/net/tipc/bcast.h index 7c1ef1b3d7b..ea162c7b30e 100644 --- a/net/tipc/bcast.h +++ b/net/tipc/bcast.h @@ -81,7 +81,7 @@ static inline int tipc_nmap_equal(struct tipc_node_map *nm_a, void tipc_port_list_add(struct tipc_port_list *pl_ptr, u32 port); void tipc_port_list_free(struct tipc_port_list *pl_ptr); -void tipc_bclink_init(void); +int tipc_bclink_init(void); void tipc_bclink_stop(void); void tipc_bclink_add_node(u32 addr); void tipc_bclink_remove_node(u32 addr); diff --git a/net/tipc/config.c b/net/tipc/config.c index 251f5a2028e..2b42403ad33 100644 --- a/net/tipc/config.c +++ b/net/tipc/config.c @@ -177,8 +177,10 @@ static struct sk_buff *cfg_set_own_addr(void) if (tipc_own_addr) return tipc_cfg_reply_error_string(TIPC_CFG_NOT_SUPPORTED " (cannot change node address once assigned)"); - tipc_net_start(addr); - return tipc_cfg_reply_none(); + if (!tipc_net_start(addr)) + return tipc_cfg_reply_none(); + + return tipc_cfg_reply_error_string("cannot change to network mode"); } static struct sk_buff *cfg_set_max_ports(void) diff --git a/net/tipc/net.c b/net/tipc/net.c index 75bb39025d5..f8fc95d58c0 100644 --- a/net/tipc/net.c +++ b/net/tipc/net.c @@ -164,20 +164,25 @@ void tipc_net_route_msg(struct sk_buff *buf) tipc_link_xmit(buf, dnode, msg_link_selector(msg)); } -void tipc_net_start(u32 addr) +int tipc_net_start(u32 addr) { char addr_string[16]; + int res; tipc_own_addr = addr; tipc_named_reinit(); tipc_port_reinit(); - tipc_bclink_init(); + res = tipc_bclink_init(); + if (res) + return res; + tipc_nametbl_publish(TIPC_CFG_SRV, tipc_own_addr, tipc_own_addr, TIPC_ZONE_SCOPE, 0, tipc_own_addr); pr_info("Started in network mode\n"); pr_info("Own node address %s, network identity %u\n", tipc_addr_string_fill(addr_string, tipc_own_addr), tipc_net_id); + return 0; } void tipc_net_stop(void) diff --git a/net/tipc/net.h b/net/tipc/net.h index f781cae8df4..c6c2b46f7c2 100644 --- a/net/tipc/net.h +++ b/net/tipc/net.h @@ -39,7 +39,7 @@ void tipc_net_route_msg(struct sk_buff *buf); -void tipc_net_start(u32 addr); +int tipc_net_start(u32 addr); void tipc_net_stop(void); #endif -- cgit v1.2.3-70-g09d2