From f03273f1e2fc8a59c3831200dd1532cf29e37e35 Mon Sep 17 00:00:00 2001 From: Ying Xue Date: Wed, 26 Nov 2014 11:41:54 +0800 Subject: [PATCH] tipc: use generic SKB list APIs to manage link receive queue Use standard SKB list APIs associated with struct sk_buff_head to manage link's receive queue to simplify its relevant code cemplexity. Signed-off-by: Ying Xue Reviewed-by: Jon Maloy Signed-off-by: David S. Miller --- net/tipc/bearer.h | 2 +- net/tipc/link.c | 83 ++++++++++++++++++++--------------------------- 2 files changed, 36 insertions(+), 49 deletions(-) diff --git a/net/tipc/bearer.h b/net/tipc/bearer.h index b1d905209e83..2c1230ac5dfe 100644 --- a/net/tipc/bearer.h +++ b/net/tipc/bearer.h @@ -165,7 +165,7 @@ extern struct tipc_bearer __rcu *bearer_list[]; * TIPC routines available to supported media types */ -void tipc_rcv(struct sk_buff *buf, struct tipc_bearer *tb_ptr); +void tipc_rcv(struct sk_buff *skb, struct tipc_bearer *tb_ptr); int tipc_enable_bearer(const char *bearer_name, u32 disc_domain, u32 priority); int tipc_disable_bearer(const char *name); diff --git a/net/tipc/link.c b/net/tipc/link.c index d9c2310e417d..0e04508cdba4 100644 --- a/net/tipc/link.c +++ b/net/tipc/link.c @@ -966,29 +966,17 @@ void tipc_link_retransmit(struct tipc_link *l_ptr, struct sk_buff *skb, } } -/** - * link_insert_deferred_queue - insert deferred messages back into receive chain - */ -static struct sk_buff *link_insert_deferred_queue(struct tipc_link *l_ptr, - struct sk_buff *buf) +static void link_retrieve_defq(struct tipc_link *link, + struct sk_buff_head *list) { - struct sk_buff_head head; - struct sk_buff *skb = NULL; u32 seq_no; - if (skb_queue_empty(&l_ptr->deferred_queue)) - return buf; + if (skb_queue_empty(&link->deferred_queue)) + return; - seq_no = buf_seqno(skb_peek(&l_ptr->deferred_queue)); - if (seq_no == mod(l_ptr->next_in_no)) { - __skb_queue_head_init(&head); - skb_queue_splice_tail_init(&l_ptr->deferred_queue, &head); - skb = head.next; - skb->prev = NULL; - head.prev->next = buf; - head.prev->prev = NULL; - } - return skb; + seq_no = buf_seqno(skb_peek(&link->deferred_queue)); + if (seq_no == mod(link->next_in_no)) + skb_queue_splice_tail_init(&link->deferred_queue, list); } /** @@ -1048,43 +1036,43 @@ static int link_recv_buf_validate(struct sk_buff *buf) /** * tipc_rcv - process TIPC packets/messages arriving from off-node - * @head: pointer to message buffer chain + * @skb: TIPC packet * @b_ptr: pointer to bearer message arrived on * * Invoked with no locks held. Bearer pointer must point to a valid bearer * structure (i.e. cannot be NULL), but bearer can be inactive. */ -void tipc_rcv(struct sk_buff *head, struct tipc_bearer *b_ptr) +void tipc_rcv(struct sk_buff *skb, struct tipc_bearer *b_ptr) { - while (head) { - struct tipc_node *n_ptr; - struct tipc_link *l_ptr; - struct sk_buff *buf = head; - struct sk_buff *skb1, *tmp; - struct tipc_msg *msg; - u32 seq_no; - u32 ackd; - u32 released; + struct sk_buff_head head; + struct tipc_node *n_ptr; + struct tipc_link *l_ptr; + struct sk_buff *skb1, *tmp; + struct tipc_msg *msg; + u32 seq_no; + u32 ackd; + u32 released; - head = head->next; - buf->next = NULL; + __skb_queue_head_init(&head); + __skb_queue_tail(&head, skb); + while ((skb = __skb_dequeue(&head))) { /* Ensure message is well-formed */ - if (unlikely(!link_recv_buf_validate(buf))) + if (unlikely(!link_recv_buf_validate(skb))) goto discard; /* Ensure message data is a single contiguous unit */ - if (unlikely(skb_linearize(buf))) + if (unlikely(skb_linearize(skb))) goto discard; /* Handle arrival of a non-unicast link message */ - msg = buf_msg(buf); + msg = buf_msg(skb); if (unlikely(msg_non_seq(msg))) { if (msg_user(msg) == LINK_CONFIG) - tipc_disc_rcv(buf, b_ptr); + tipc_disc_rcv(skb, b_ptr); else - tipc_bclink_rcv(buf); + tipc_bclink_rcv(skb); continue; } @@ -1145,8 +1133,8 @@ void tipc_rcv(struct sk_buff *head, struct tipc_bearer *b_ptr) /* Process the incoming packet */ if (unlikely(!link_working_working(l_ptr))) { if (msg_user(msg) == LINK_PROTOCOL) { - tipc_link_proto_rcv(l_ptr, buf); - head = link_insert_deferred_queue(l_ptr, head); + tipc_link_proto_rcv(l_ptr, skb); + link_retrieve_defq(l_ptr, &head); tipc_node_unlock(n_ptr); continue; } @@ -1156,8 +1144,7 @@ void tipc_rcv(struct sk_buff *head, struct tipc_bearer *b_ptr) if (link_working_working(l_ptr)) { /* Re-insert buffer in front of queue */ - buf->next = head; - head = buf; + __skb_queue_head(&head, skb); tipc_node_unlock(n_ptr); continue; } @@ -1166,33 +1153,33 @@ void tipc_rcv(struct sk_buff *head, struct tipc_bearer *b_ptr) /* Link is now in state WORKING_WORKING */ if (unlikely(seq_no != mod(l_ptr->next_in_no))) { - link_handle_out_of_seq_msg(l_ptr, buf); - head = link_insert_deferred_queue(l_ptr, head); + link_handle_out_of_seq_msg(l_ptr, skb); + link_retrieve_defq(l_ptr, &head); tipc_node_unlock(n_ptr); continue; } l_ptr->next_in_no++; if (unlikely(!skb_queue_empty(&l_ptr->deferred_queue))) - head = link_insert_deferred_queue(l_ptr, head); + link_retrieve_defq(l_ptr, &head); if (unlikely(++l_ptr->unacked_window >= TIPC_MIN_LINK_WIN)) { l_ptr->stats.sent_acks++; tipc_link_proto_xmit(l_ptr, STATE_MSG, 0, 0, 0, 0, 0); } - if (tipc_link_prepare_input(l_ptr, &buf)) { + if (tipc_link_prepare_input(l_ptr, &skb)) { tipc_node_unlock(n_ptr); continue; } tipc_node_unlock(n_ptr); - msg = buf_msg(buf); - if (tipc_link_input(l_ptr, buf) != 0) + + if (tipc_link_input(l_ptr, skb) != 0) goto discard; continue; unlock_discard: tipc_node_unlock(n_ptr); discard: - kfree_skb(buf); + kfree_skb(skb); } }