From 9db9fdd1983eb960182d72f95d77b91b3a5173d0 Mon Sep 17 00:00:00 2001 From: Ying Xue Date: Mon, 5 May 2014 08:56:12 +0800 Subject: tipc: avoid to asynchronously notify subscriptions Postpone the actions of notifying subscriptions until after node lock is released, avoiding to asynchronously execute registered handlers when node is lost. Signed-off-by: Ying Xue Reviewed-by: Erik Hugne Reviewed-by: Jon Maloy Signed-off-by: David S. Miller --- net/tipc/node.c | 23 +++++++++++++++++++++-- net/tipc/node.h | 15 +++++++-------- net/tipc/node_subscr.c | 9 ++++----- net/tipc/node_subscr.h | 2 +- 4 files changed, 33 insertions(+), 16 deletions(-) (limited to 'net/tipc') diff --git a/net/tipc/node.c b/net/tipc/node.c index 2b0a0849d4cc..befbcc9eade6 100644 --- a/net/tipc/node.c +++ b/net/tipc/node.c @@ -321,10 +321,10 @@ static void node_lost_contact(struct tipc_node *n_ptr) } /* Notify subscribers */ - tipc_nodesub_notify(n_ptr); + n_ptr->flags = TIPC_NODE_LOST; /* Prevent re-contact with node until cleanup is done */ - n_ptr->flags = TIPC_NODE_DOWN | TIPC_NAMES_GONE; + n_ptr->flags |= TIPC_NODE_DOWN | TIPC_NAMES_GONE; tipc_k_signal((Handler)node_name_purge_complete, n_ptr->addr); } @@ -465,3 +465,22 @@ int tipc_node_get_linkname(u32 bearer_id, u32 addr, char *linkname, size_t len) tipc_node_unlock(node); return -EINVAL; } + +void tipc_node_unlock(struct tipc_node *node) +{ + LIST_HEAD(nsub_list); + + if (likely(!node->flags)) { + spin_unlock_bh(&node->lock); + return; + } + + if (node->flags & TIPC_NODE_LOST) { + list_replace_init(&node->nsub, &nsub_list); + node->flags &= ~TIPC_NODE_LOST; + } + spin_unlock_bh(&node->lock); + + if (!list_empty(&nsub_list)) + tipc_nodesub_notify(&nsub_list); +} diff --git a/net/tipc/node.h b/net/tipc/node.h index 242b918ddd14..fd86726ed192 100644 --- a/net/tipc/node.h +++ b/net/tipc/node.h @@ -51,11 +51,14 @@ * TIPC_NODE_DOWN: indicate node is down * TIPC_NAMES_GONE: indicate the node's publications are purged * TIPC_NODE_RESET: indicate node is reset + * TIPC_NODE_LOST: indicate node is lost and it's used to notify subscriptions + * when node lock is released */ enum { TIPC_NODE_DOWN = (1 << 1), TIPC_NAMES_GONE = (1 << 2), - TIPC_NODE_RESET = (1 << 3) + TIPC_NODE_RESET = (1 << 3), + TIPC_NODE_LOST = (1 << 4) }; /** @@ -130,15 +133,11 @@ int tipc_node_is_up(struct tipc_node *n_ptr); struct sk_buff *tipc_node_get_links(const void *req_tlv_area, int req_tlv_space); struct sk_buff *tipc_node_get_nodes(const void *req_tlv_area, int req_tlv_space); int tipc_node_get_linkname(u32 bearer_id, u32 node, char *linkname, size_t len); +void tipc_node_unlock(struct tipc_node *node); -static inline void tipc_node_lock(struct tipc_node *n_ptr) +static inline void tipc_node_lock(struct tipc_node *node) { - spin_lock_bh(&n_ptr->lock); -} - -static inline void tipc_node_unlock(struct tipc_node *n_ptr) -{ - spin_unlock_bh(&n_ptr->lock); + spin_lock_bh(&node->lock); } static inline bool tipc_node_blocked(struct tipc_node *node) diff --git a/net/tipc/node_subscr.c b/net/tipc/node_subscr.c index 8a7384c04add..7c59ab1d6ecb 100644 --- a/net/tipc/node_subscr.c +++ b/net/tipc/node_subscr.c @@ -81,14 +81,13 @@ void tipc_nodesub_unsubscribe(struct tipc_node_subscr *node_sub) * * Note: node is locked by caller */ -void tipc_nodesub_notify(struct tipc_node *node) +void tipc_nodesub_notify(struct list_head *nsub_list) { - struct tipc_node_subscr *ns; + struct tipc_node_subscr *ns, *safe; - list_for_each_entry(ns, &node->nsub, nodesub_list) { + list_for_each_entry_safe(ns, safe, nsub_list, nodesub_list) { if (ns->handle_node_down) { - tipc_k_signal((Handler)ns->handle_node_down, - (unsigned long)ns->usr_handle); + ns->handle_node_down(ns->usr_handle); ns->handle_node_down = NULL; } } diff --git a/net/tipc/node_subscr.h b/net/tipc/node_subscr.h index c95d20727ded..d91b8cc81e3d 100644 --- a/net/tipc/node_subscr.h +++ b/net/tipc/node_subscr.h @@ -58,6 +58,6 @@ struct tipc_node_subscr { void tipc_nodesub_subscribe(struct tipc_node_subscr *node_sub, u32 addr, void *usr_handle, net_ev_handler handle_down); void tipc_nodesub_unsubscribe(struct tipc_node_subscr *node_sub); -void tipc_nodesub_notify(struct tipc_node *node); +void tipc_nodesub_notify(struct list_head *nsub_list); #endif -- cgit v1.2.3