From: Allan Stephens Date: Mon, 26 Jun 2006 06:40:01 +0000 (-0700) Subject: [TIPC]: Multicast link failure now resets all links to "nacking" node. X-Git-Tag: v2.6.18-rc1~614^2~35 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=d356eeba8e34786621d85468e5176052813a3059;p=linux-2.6 [TIPC]: Multicast link failure now resets all links to "nacking" node. This fix prevents node from crashing. Signed-off-by: Allan Stephens Signed-off-by: Per Liden Signed-off-by: David S. Miller --- diff --git a/net/tipc/bcast.c b/net/tipc/bcast.c index 2c4ecbe500..00691b7c35 100644 --- a/net/tipc/bcast.c +++ b/net/tipc/bcast.c @@ -49,13 +49,19 @@ #include "name_table.h" #include "bcast.h" - #define MAX_PKT_DEFAULT_MCAST 1500 /* bcast link max packet size (fixed) */ #define BCLINK_WIN_DEFAULT 20 /* bcast link window size (default) */ #define BCLINK_LOG_BUF_SIZE 0 +/* + * Loss rate for incoming broadcast frames; used to test retransmission code. + * Set to N to cause every N'th frame to be discarded; 0 => don't discard any. + */ + +#define TIPC_BCAST_LOSS_RATE 0 + /** * struct bcbearer_pair - a pair of bearers used by broadcast link * @primary: pointer to primary bearer @@ -165,21 +171,18 @@ static int bclink_ack_allowed(u32 n) * @after: sequence number of last packet to *not* retransmit * @to: sequence number of last packet to retransmit * - * Called with 'node' locked, bc_lock unlocked + * Called with bc_lock locked */ static void bclink_retransmit_pkt(u32 after, u32 to) { struct sk_buff *buf; - spin_lock_bh(&bc_lock); buf = bcl->first_out; while (buf && less_eq(buf_seqno(buf), after)) { buf = buf->next; } - if (buf != NULL) - tipc_link_retransmit(bcl, buf, mod(to - after)); - spin_unlock_bh(&bc_lock); + tipc_link_retransmit(bcl, buf, mod(to - after)); } /** @@ -399,7 +402,10 @@ int tipc_bclink_send_msg(struct sk_buff *buf) */ void tipc_bclink_recv_pkt(struct sk_buff *buf) -{ +{ +#if (TIPC_BCAST_LOSS_RATE) + static int rx_count = 0; +#endif struct tipc_msg *msg = buf_msg(buf); struct node* node = tipc_node_find(msg_prevnode(msg)); u32 next_in; @@ -420,9 +426,13 @@ void tipc_bclink_recv_pkt(struct sk_buff *buf) tipc_node_lock(node); tipc_bclink_acknowledge(node, msg_bcast_ack(msg)); tipc_node_unlock(node); + spin_lock_bh(&bc_lock); bcl->stats.recv_nacks++; + bcl->owner->next = node; /* remember requestor */ bclink_retransmit_pkt(msg_bcgap_after(msg), msg_bcgap_to(msg)); + bcl->owner->next = NULL; + spin_unlock_bh(&bc_lock); } else { tipc_bclink_peek_nack(msg_destnode(msg), msg_bcast_tag(msg), @@ -433,6 +443,14 @@ void tipc_bclink_recv_pkt(struct sk_buff *buf) return; } +#if (TIPC_BCAST_LOSS_RATE) + if (++rx_count == TIPC_BCAST_LOSS_RATE) { + rx_count = 0; + buf_discard(buf); + return; + } +#endif + tipc_node_lock(node); receive: deferred = node->bclink.deferred_head; diff --git a/net/tipc/link.c b/net/tipc/link.c index 955b87d9b4..ba7d3f19be 100644 --- a/net/tipc/link.c +++ b/net/tipc/link.c @@ -1604,40 +1604,121 @@ void tipc_link_push_queue(struct link *l_ptr) tipc_bearer_schedule(l_ptr->b_ptr, l_ptr); } +static void link_reset_all(unsigned long addr) +{ + struct node *n_ptr; + char addr_string[16]; + u32 i; + + read_lock_bh(&tipc_net_lock); + n_ptr = tipc_node_find((u32)addr); + if (!n_ptr) { + read_unlock_bh(&tipc_net_lock); + return; /* node no longer exists */ + } + + tipc_node_lock(n_ptr); + + warn("Resetting all links to %s\n", + addr_string_fill(addr_string, n_ptr->addr)); + + for (i = 0; i < MAX_BEARERS; i++) { + if (n_ptr->links[i]) { + link_print(n_ptr->links[i], TIPC_OUTPUT, + "Resetting link\n"); + tipc_link_reset(n_ptr->links[i]); + } + } + + tipc_node_unlock(n_ptr); + read_unlock_bh(&tipc_net_lock); +} + +static void link_retransmit_failure(struct link *l_ptr, struct sk_buff *buf) +{ + struct tipc_msg *msg = buf_msg(buf); + + warn("Retransmission failure on link <%s>\n", l_ptr->name); + tipc_msg_print(TIPC_OUTPUT, msg, ">RETR-FAIL>"); + + if (l_ptr->addr) { + + /* Handle failure on standard link */ + + link_print(l_ptr, TIPC_OUTPUT, "Resetting link\n"); + tipc_link_reset(l_ptr); + + } else { + + /* Handle failure on broadcast link */ + + struct node *n_ptr; + char addr_string[16]; + + tipc_printf(TIPC_OUTPUT, "Msg seq number: %u, ", msg_seqno(msg)); + tipc_printf(TIPC_OUTPUT, "Outstanding acks: %u\n", (u32)TIPC_SKB_CB(buf)->handle); + + n_ptr = l_ptr->owner->next; + tipc_node_lock(n_ptr); + + addr_string_fill(addr_string, n_ptr->addr); + tipc_printf(TIPC_OUTPUT, "Multicast link info for %s\n", addr_string); + tipc_printf(TIPC_OUTPUT, "Supported: %d, ", n_ptr->bclink.supported); + tipc_printf(TIPC_OUTPUT, "Acked: %u\n", n_ptr->bclink.acked); + tipc_printf(TIPC_OUTPUT, "Last in: %u, ", n_ptr->bclink.last_in); + tipc_printf(TIPC_OUTPUT, "Gap after: %u, ", n_ptr->bclink.gap_after); + tipc_printf(TIPC_OUTPUT, "Gap to: %u\n", n_ptr->bclink.gap_to); + tipc_printf(TIPC_OUTPUT, "Nack sync: %u\n\n", n_ptr->bclink.nack_sync); + + tipc_k_signal((Handler)link_reset_all, (unsigned long)n_ptr->addr); + + tipc_node_unlock(n_ptr); + + l_ptr->stale_count = 0; + } +} + void tipc_link_retransmit(struct link *l_ptr, struct sk_buff *buf, u32 retransmits) { struct tipc_msg *msg; + if (!buf) + return; + + msg = buf_msg(buf); + dbg("Retransmitting %u in link %x\n", retransmits, l_ptr); - if (tipc_bearer_congested(l_ptr->b_ptr, l_ptr) && buf && !skb_cloned(buf)) { - msg_dbg(buf_msg(buf), ">NO_RETR->BCONG>"); - dbg_print_link(l_ptr, " "); - l_ptr->retransm_queue_head = msg_seqno(buf_msg(buf)); - l_ptr->retransm_queue_size = retransmits; - return; + if (tipc_bearer_congested(l_ptr->b_ptr, l_ptr)) { + if (!skb_cloned(buf)) { + msg_dbg(msg, ">NO_RETR->BCONG>"); + dbg_print_link(l_ptr, " "); + l_ptr->retransm_queue_head = msg_seqno(msg); + l_ptr->retransm_queue_size = retransmits; + return; + } else { + /* Don't retransmit if driver already has the buffer */ + } + } else { + /* Detect repeated retransmit failures on uncongested bearer */ + + if (l_ptr->last_retransmitted == msg_seqno(msg)) { + if (++l_ptr->stale_count > 100) { + link_retransmit_failure(l_ptr, buf); + return; + } + } else { + l_ptr->last_retransmitted = msg_seqno(msg); + l_ptr->stale_count = 1; + } } + while (retransmits && (buf != l_ptr->next_out) && buf && !skb_cloned(buf)) { msg = buf_msg(buf); msg_set_ack(msg, mod(l_ptr->next_in_no - 1)); msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in); if (tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr)) { - /* Catch if retransmissions fail repeatedly: */ - if (l_ptr->last_retransmitted == msg_seqno(msg)) { - if (++l_ptr->stale_count > 100) { - tipc_msg_print(TIPC_CONS, buf_msg(buf), ">RETR>"); - info("...Retransmitted %u times\n", - l_ptr->stale_count); - link_print(l_ptr, TIPC_CONS, "Resetting Link\n"); - tipc_link_reset(l_ptr); - break; - } - } else { - l_ptr->stale_count = 0; - } - l_ptr->last_retransmitted = msg_seqno(msg); - msg_dbg(buf_msg(buf), ">RETR>"); buf = buf->next; retransmits--; @@ -1650,6 +1731,7 @@ void tipc_link_retransmit(struct link *l_ptr, struct sk_buff *buf, return; } } + l_ptr->retransm_queue_head = l_ptr->retransm_queue_size = 0; }