From 6a6b5c8bff89c76b09a921ef05b042fdee940f2a Mon Sep 17 00:00:00 2001 From: Tuong Lien Date: Mon, 17 Jun 2019 12:15:42 +0700 Subject: tipc: include retrans failure detection for unicast In patch series, commit 9195948fbf34 ("tipc: improve TIPC throughput by Gap ACK blocks"), as for simplicity, the repeated retransmit failures' detection in the function - "tipc_link_retrans()" was kept there for broadcast retransmissions only. This commit now reapplies this feature for link unicast retransmissions that has been done via the function - "tipc_link_advance_transmq()". Also, the "tipc_link_retrans()" is renamed to "tipc_link_bc_retrans()" as it is used only for broadcast. Acked-by: Jon Maloy Signed-off-by: Tuong Lien Signed-off-by: David S. Miller --- net/tipc/link.c | 106 +++++++++++++++++++++++++++++++++++++------------------- 1 file changed, 70 insertions(+), 36 deletions(-) (limited to 'net/tipc/link.c') diff --git a/net/tipc/link.c b/net/tipc/link.c index f5cd986e1e50..d5ed509e0660 100644 --- a/net/tipc/link.c +++ b/net/tipc/link.c @@ -249,9 +249,9 @@ static void tipc_link_build_bc_init_msg(struct tipc_link *l, struct sk_buff_head *xmitq); static bool tipc_link_release_pkts(struct tipc_link *l, u16 to); static u16 tipc_build_gap_ack_blks(struct tipc_link *l, void *data); -static void tipc_link_advance_transmq(struct tipc_link *l, u16 acked, u16 gap, - struct tipc_gap_ack_blks *ga, - struct sk_buff_head *xmitq); +static int tipc_link_advance_transmq(struct tipc_link *l, u16 acked, u16 gap, + struct tipc_gap_ack_blks *ga, + struct sk_buff_head *xmitq); /* * Simple non-static link routines (i.e. referenced outside this file) @@ -1044,32 +1044,69 @@ static void tipc_link_advance_backlog(struct tipc_link *l, l->snd_nxt = seqno; } -static void link_retransmit_failure(struct tipc_link *l, struct sk_buff *skb) +/** + * link_retransmit_failure() - Detect repeated retransmit failures + * @l: tipc link sender + * @r: tipc link receiver (= l in case of unicast) + * @from: seqno of the 1st packet in retransmit request + * @rc: returned code + * + * Return: true if the repeated retransmit failures happens, otherwise + * false + */ +static bool link_retransmit_failure(struct tipc_link *l, struct tipc_link *r, + u16 from, int *rc) { - struct tipc_msg *hdr = buf_msg(skb); + struct sk_buff *skb = skb_peek(&l->transmq); + struct tipc_msg *hdr; + + if (!skb) + return false; + hdr = buf_msg(skb); + + /* Detect repeated retransmit failures on same packet */ + if (r->prev_from != from) { + r->prev_from = from; + r->stale_limit = jiffies + msecs_to_jiffies(r->tolerance); + r->stale_cnt = 0; + } else if (++r->stale_cnt > 99 && time_after(jiffies, r->stale_limit)) { + pr_warn("Retransmission failure on link <%s>\n", l->name); + link_print(l, "State of link "); + pr_info("Failed msg: usr %u, typ %u, len %u, err %u\n", + msg_user(hdr), msg_type(hdr), msg_size(hdr), + msg_errcode(hdr)); + pr_info("sqno %u, prev: %x, src: %x\n", + msg_seqno(hdr), msg_prevnode(hdr), msg_orignode(hdr)); + + trace_tipc_list_dump(&l->transmq, true, "retrans failure!"); + trace_tipc_link_dump(l, TIPC_DUMP_NONE, "retrans failure!"); + trace_tipc_link_dump(r, TIPC_DUMP_NONE, "retrans failure!"); + + if (link_is_bc_sndlink(l)) + *rc = TIPC_LINK_DOWN_EVT; + + *rc = tipc_link_fsm_evt(l, LINK_FAILURE_EVT); + return true; + } - pr_warn("Retransmission failure on link <%s>\n", l->name); - link_print(l, "State of link "); - pr_info("Failed msg: usr %u, typ %u, len %u, err %u\n", - msg_user(hdr), msg_type(hdr), msg_size(hdr), msg_errcode(hdr)); - pr_info("sqno %u, prev: %x, src: %x\n", - msg_seqno(hdr), msg_prevnode(hdr), msg_orignode(hdr)); + return false; } -/* tipc_link_retrans() - retransmit one or more packets +/* tipc_link_bc_retrans() - retransmit zero or more packets * @l: the link to transmit on * @r: the receiving link ordering the retransmit. Same as l if unicast * @from: retransmit from (inclusive) this sequence number * @to: retransmit to (inclusive) this sequence number * xmitq: queue for accumulating the retransmitted packets */ -static int tipc_link_retrans(struct tipc_link *l, struct tipc_link *r, - u16 from, u16 to, struct sk_buff_head *xmitq) +static int tipc_link_bc_retrans(struct tipc_link *l, struct tipc_link *r, + u16 from, u16 to, struct sk_buff_head *xmitq) { struct sk_buff *_skb, *skb = skb_peek(&l->transmq); u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1; u16 ack = l->rcv_nxt - 1; struct tipc_msg *hdr; + int rc = 0; if (!skb) return 0; @@ -1077,20 +1114,9 @@ static int tipc_link_retrans(struct tipc_link *l, struct tipc_link *r, return 0; trace_tipc_link_retrans(r, from, to, &l->transmq); - /* Detect repeated retransmit failures on same packet */ - if (r->prev_from != from) { - r->prev_from = from; - r->stale_limit = jiffies + msecs_to_jiffies(r->tolerance); - r->stale_cnt = 0; - } else if (++r->stale_cnt > 99 && time_after(jiffies, r->stale_limit)) { - link_retransmit_failure(l, skb); - trace_tipc_list_dump(&l->transmq, true, "retrans failure!"); - trace_tipc_link_dump(l, TIPC_DUMP_NONE, "retrans failure!"); - trace_tipc_link_dump(r, TIPC_DUMP_NONE, "retrans failure!"); - if (link_is_bc_sndlink(l)) - return TIPC_LINK_DOWN_EVT; - return tipc_link_fsm_evt(l, LINK_FAILURE_EVT); - } + + if (link_retransmit_failure(l, r, from, &rc)) + return rc; skb_queue_walk(&l->transmq, skb) { hdr = buf_msg(skb); @@ -1324,17 +1350,23 @@ exit: * @gap: # of gap packets * @ga: buffer pointer to Gap ACK blocks from peer * @xmitq: queue for accumulating the retransmitted packets if any + * + * In case of a repeated retransmit failures, the call will return shortly + * with a returned code (e.g. TIPC_LINK_DOWN_EVT) */ -static void tipc_link_advance_transmq(struct tipc_link *l, u16 acked, u16 gap, - struct tipc_gap_ack_blks *ga, - struct sk_buff_head *xmitq) +static int tipc_link_advance_transmq(struct tipc_link *l, u16 acked, u16 gap, + struct tipc_gap_ack_blks *ga, + struct sk_buff_head *xmitq) { struct sk_buff *skb, *_skb, *tmp; struct tipc_msg *hdr; u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1; u16 ack = l->rcv_nxt - 1; - u16 seqno; - u16 n = 0; + u16 seqno, n = 0; + int rc = 0; + + if (gap && link_retransmit_failure(l, l, acked + 1, &rc)) + return rc; skb_queue_walk_safe(&l->transmq, skb, tmp) { seqno = buf_seqno(skb); @@ -1369,6 +1401,8 @@ next_gap_ack: goto next_gap_ack; } } + + return 0; } /* tipc_link_build_state_msg: prepare link state message for transmission @@ -1919,7 +1953,7 @@ static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb, tipc_link_build_proto_msg(l, STATE_MSG, 0, reply, rcvgap, 0, 0, xmitq); - tipc_link_advance_transmq(l, ack, gap, ga, xmitq); + rc |= tipc_link_advance_transmq(l, ack, gap, ga, xmitq); /* If NACK, retransmit will now start at right position */ if (gap) @@ -2036,7 +2070,7 @@ int tipc_link_bc_sync_rcv(struct tipc_link *l, struct tipc_msg *hdr, if (more(peers_snd_nxt, l->rcv_nxt + l->window)) return rc; - rc = tipc_link_retrans(snd_l, l, from, to, xmitq); + rc = tipc_link_bc_retrans(snd_l, l, from, to, xmitq); l->snd_nxt = peers_snd_nxt; if (link_bc_rcv_gap(l)) @@ -2132,7 +2166,7 @@ int tipc_link_bc_nack_rcv(struct tipc_link *l, struct sk_buff *skb, if (dnode == tipc_own_addr(l->net)) { tipc_link_bc_ack_rcv(l, acked, xmitq); - rc = tipc_link_retrans(l->bc_sndlink, l, from, to, xmitq); + rc = tipc_link_bc_retrans(l->bc_sndlink, l, from, to, xmitq); l->stats.recv_nacks++; return rc; } -- cgit v1.2.3-59-g8ed1b