From 6d4ebeb4df0176b1973875840a9f7e91394c0685 Mon Sep 17 00:00:00 2001 From: Ying Xue Date: Thu, 6 Mar 2014 14:40:16 +0100 Subject: [PATCH] tipc: allow connection shutdown callback to be invoked in advance Currently connection shutdown callback function is called when connection instance is released in tipc_conn_kref_release(), and receiving packets and sending packets are running in different threads. Even if connection is closed by the thread of receiving packets, its shutdown callback may not be called immediately as the connection reference count is non-zero at that moment. So, although the connection is shut down by the thread of receiving packets, the thread of sending packets doesn't know it. Before its shutdown callback is invoked to tell the sending thread its connection has been closed, the sending thread may deliver messages by tipc_conn_sendmsg(), this is why the following error information appears: "Sending subscription event failed, no memory" To eliminate it, allow connection shutdown callback function to be called before connection id is removed in tipc_close_conn(), which makes the sending thread know the truth in time that its socket is closed so that it doesn't send message to it. We also remove the "Sending XXX failed..." error reporting for topology and config services. Signed-off-by: Ying Xue Signed-off-by: Erik Hugne Reviewed-by: Jon Maloy Signed-off-by: David S. Miller --- net/tipc/config.c | 9 ++------- net/tipc/server.c | 8 +++----- net/tipc/subscr.c | 8 ++------ 3 files changed, 7 insertions(+), 18 deletions(-) diff --git a/net/tipc/config.c b/net/tipc/config.c index e74eef2..e6d7216 100644 --- a/net/tipc/config.c +++ b/net/tipc/config.c @@ -376,7 +376,6 @@ static void cfg_conn_msg_event(int conid, struct sockaddr_tipc *addr, struct tipc_cfg_msg_hdr *req_hdr; struct tipc_cfg_msg_hdr *rep_hdr; struct sk_buff *rep_buf; - int ret; /* Validate configuration message header (ignore invalid message) */ req_hdr = (struct tipc_cfg_msg_hdr *)buf; @@ -398,12 +397,8 @@ static void cfg_conn_msg_event(int conid, struct sockaddr_tipc *addr, memcpy(rep_hdr, req_hdr, sizeof(*rep_hdr)); rep_hdr->tcm_len = htonl(rep_buf->len); rep_hdr->tcm_flags &= htons(~TCM_F_REQUEST); - - ret = tipc_conn_sendmsg(&cfgsrv, conid, addr, rep_buf->data, - rep_buf->len); - if (ret < 0) - pr_err("Sending cfg reply message failed, no memory\n"); - + tipc_conn_sendmsg(&cfgsrv, conid, addr, rep_buf->data, + rep_buf->len); kfree_skb(rep_buf); } } diff --git a/net/tipc/server.c b/net/tipc/server.c index 3739797..bbaa8f5 100644 --- a/net/tipc/server.c +++ b/net/tipc/server.c @@ -87,7 +87,6 @@ static void tipc_clean_outqueues(struct tipc_conn *con); static void tipc_conn_kref_release(struct kref *kref) { struct tipc_conn *con = container_of(kref, struct tipc_conn, kref); - struct tipc_server *s = con->server; if (con->sock) { tipc_sock_release_local(con->sock); @@ -95,10 +94,6 @@ static void tipc_conn_kref_release(struct kref *kref) } tipc_clean_outqueues(con); - - if (con->conid) - s->tipc_conn_shutdown(con->conid, con->usr_data); - kfree(con); } @@ -181,6 +176,9 @@ static void tipc_close_conn(struct tipc_conn *con) struct tipc_server *s = con->server; if (test_and_clear_bit(CF_CONNECTED, &con->flags)) { + if (con->conid) + s->tipc_conn_shutdown(con->conid, con->usr_data); + spin_lock_bh(&s->idr_lock); idr_remove(&s->conn_idr, con->conid); s->idr_in_use--; diff --git a/net/tipc/subscr.c b/net/tipc/subscr.c index 7cb0bd5..a6ce3bb 100644 --- a/net/tipc/subscr.c +++ b/net/tipc/subscr.c @@ -96,20 +96,16 @@ static void subscr_send_event(struct tipc_subscription *sub, u32 found_lower, { struct tipc_subscriber *subscriber = sub->subscriber; struct kvec msg_sect; - int ret; msg_sect.iov_base = (void *)&sub->evt; msg_sect.iov_len = sizeof(struct tipc_event); - sub->evt.event = htohl(event, sub->swap); sub->evt.found_lower = htohl(found_lower, sub->swap); sub->evt.found_upper = htohl(found_upper, sub->swap); sub->evt.port.ref = htohl(port_ref, sub->swap); sub->evt.port.node = htohl(node, sub->swap); - ret = tipc_conn_sendmsg(&topsrv, subscriber->conid, NULL, - msg_sect.iov_base, msg_sect.iov_len); - if (ret < 0) - pr_err("Sending subscription event failed, no memory\n"); + tipc_conn_sendmsg(&topsrv, subscriber->conid, NULL, msg_sect.iov_base, + msg_sect.iov_len); } /** -- 2.7.4