/*
* net/tipc/bcast.c: TIPC broadcast code
- *
+ *
* Copyright (c) 2004-2006, Ericsson AB
* Copyright (c) 2004, Intel Corporation.
* Copyright (c) 2005, Wind River Systems
#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
* @secondary: pointer to secondary bearer
- *
- * Bearers must have same priority and same set of reachable destinations
+ *
+ * Bearers must have same priority and same set of reachable destinations
* to be paired.
*/
* @bearer: (non-standard) broadcast bearer structure
* @media: (non-standard) broadcast media structure
* @bpairs: array of bearer pairs
- * @bpairs_temp: array of bearer pairs used during creation of "bpairs"
+ * @bpairs_temp: temporary array of bearer pairs used by tipc_bcbearer_sort()
+ * @remains: temporary node map used by tipc_bcbearer_send()
+ * @remains_new: temporary node map used tipc_bcbearer_send()
+ *
+ * Note: The fields labelled "temporary" are incorporated into the bearer
+ * to avoid consuming potentially limited stack space through the use of
+ * large local variables within multicast routines. Concurrent access is
+ * prevented through use of the spinlock "bc_lock".
*/
struct bcbearer {
struct media media;
struct bcbearer_pair bpairs[MAX_BEARERS];
struct bcbearer_pair bpairs_temp[TIPC_MAX_LINK_PRI + 1];
+ struct node_map remains;
+ struct node_map remains_new;
};
/**
* struct bclink - link used for broadcast messages
* @link: (non-standard) broadcast link structure
* @node: (non-standard) node structure representing b'cast link's peer node
- *
+ *
* Handles sequence numbering, fragmentation, bundling, etc.
*/
static struct bcbearer *bcbearer = NULL;
static struct bclink *bclink = NULL;
static struct link *bcl = NULL;
-static spinlock_t bc_lock = SPIN_LOCK_UNLOCKED;
+static DEFINE_SPINLOCK(bc_lock);
char tipc_bclink_name[] = "multicast-link";
static u32 buf_seqno(struct sk_buff *buf)
{
return msg_seqno(buf_msg(buf));
-}
+}
static u32 bcbuf_acks(struct sk_buff *buf)
{
}
-/**
+/**
* bclink_set_gap - set gap according to contents of current deferred pkt queue
- *
+ *
* Called with 'node' locked, bc_lock unlocked
*/
n_ptr->bclink.gap_to = mod(buf_seqno(buf) - 1);
}
-/**
+/**
* bclink_ack_allowed - test if ACK or NACK message can be sent at this moment
- *
+ *
* This mechanism endeavours to prevent all nodes in network from trying
* to ACK or NACK at the same time.
- *
+ *
* Note: TIPC uses a different trigger to distribute ACKs than it does to
- * distribute NACKs, but tries to use the same spacing (divide by 16).
+ * distribute NACKs, but tries to use the same spacing (divide by 16).
*/
static int bclink_ack_allowed(u32 n)
}
-/**
+/**
* bclink_retransmit_pkt - retransmit broadcast packets
* @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;
+ 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));
}
-/**
+/**
* tipc_bclink_acknowledge - handle acknowledgement of broadcast packets
* @n_ptr: node that sent acknowledgement info
* @acked: broadcast sequence # that has been acknowledged
- *
+ *
* Node is locked, bc_lock unlocked.
*/
spin_unlock_bh(&bc_lock);
}
-/**
+/**
* bclink_send_ack - unicast an ACK msg
- *
+ *
* tipc_net_lock and node lock set
*/
tipc_link_send_proto_msg(l_ptr, STATE_MSG, 0, 0, 0, 0, 0);
}
-/**
+/**
* bclink_send_nack- broadcast a NACK msg
- *
+ *
* tipc_net_lock and node lock set
*/
msg_init(msg, BCAST_PROTOCOL, STATE_MSG,
TIPC_OK, INT_H_SIZE, n_ptr->addr);
msg_set_mc_netid(msg, tipc_net_id);
- msg_set_bcast_ack(msg, mod(n_ptr->bclink.last_in));
+ msg_set_bcast_ack(msg, mod(n_ptr->bclink.last_in));
msg_set_bcgap_after(msg, n_ptr->bclink.gap_after);
msg_set_bcgap_to(msg, n_ptr->bclink.gap_to);
msg_set_bcast_tag(msg, tipc_own_tag);
bcl->stats.bearer_congs++;
}
- /*
+ /*
* Ensure we doesn't send another NACK msg to the node
* until 16 more deferred messages arrive from it
* (i.e. helps prevent all nodes from NACK'ing at same time)
*/
-
+
n_ptr->bclink.nack_sync = tipc_own_tag;
}
}
-/**
+/**
* tipc_bclink_check_gap - send a NACK if a sequence gap exists
*
* tipc_net_lock and node lock set
bclink_send_nack(n_ptr);
}
-/**
+/**
* tipc_bclink_peek_nack - process a NACK msg meant for another node
- *
+ *
* Only tipc_net_lock set.
*/
if (less_eq(my_to, gap_to))
n_ptr->bclink.gap_to = gap_after;
} else {
- /*
+ /*
* Expand gap if missing bufs not in deferred queue:
*/
struct sk_buff *buf = n_ptr->bclink.deferred_head;
for (; buf; buf = buf->next) {
u32 seqno = buf_seqno(buf);
- if (mod(seqno - prev) != 1)
+ if (mod(seqno - prev) != 1) {
buf = NULL;
+ break;
+ }
if (seqno == gap_after)
break;
prev = seqno;
}
/*
* Some nodes may send a complementary NACK now:
- */
+ */
if (bclink_ack_allowed(sender_tag + 1)) {
if (n_ptr->bclink.gap_to != n_ptr->bclink.gap_after) {
bclink_send_nack(n_ptr);
/**
* tipc_bclink_recv_pkt - receive a broadcast packet, and deliver upwards
- *
+ *
* tipc_net_lock is read_locked, no other locks set
*/
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;
msg_dbg(msg, "<BC<<<");
- if (unlikely(!node || !tipc_node_is_up(node) || !node->bclink.supported ||
+ if (unlikely(!node || !tipc_node_is_up(node) || !node->bclink.supported ||
(msg_mc_netid(msg) != tipc_net_id))) {
buf_discard(buf);
return;
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),
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;
/**
* tipc_bcbearer_send - send a packet through the broadcast pseudo-bearer
- *
+ *
* Send through as many bearers as necessary to reach all nodes
* that support TIPC multicasting.
- *
+ *
* Returns 0 if packet sent successfully, non-zero if not
*/
{
static int send_count = 0;
- struct node_map *remains;
- struct node_map *remains_new;
- struct node_map *remains_tmp;
int bp_index;
int swap_time;
- int err;
/* Prepare buffer for broadcasting (if first time trying to send it) */
send_count = 0;
/* Send buffer over bearers until all targets reached */
-
- remains = kmalloc(sizeof(struct node_map), GFP_ATOMIC);
- remains_new = kmalloc(sizeof(struct node_map), GFP_ATOMIC);
- *remains = tipc_cltr_bcast_nodes;
+
+ bcbearer->remains = tipc_cltr_bcast_nodes;
for (bp_index = 0; bp_index < MAX_BEARERS; bp_index++) {
struct bearer *p = bcbearer->bpairs[bp_index].primary;
if (!p)
break; /* no more bearers to try */
- tipc_nmap_diff(remains, &p->nodes, remains_new);
- if (remains_new->count == remains->count)
+ tipc_nmap_diff(&bcbearer->remains, &p->nodes, &bcbearer->remains_new);
+ if (bcbearer->remains_new.count == bcbearer->remains.count)
continue; /* bearer pair doesn't add anything */
if (!p->publ.blocked &&
bcbearer->bpairs[bp_index].primary = s;
bcbearer->bpairs[bp_index].secondary = p;
update:
- if (remains_new->count == 0) {
- err = TIPC_OK;
- goto out;
- }
+ if (bcbearer->remains_new.count == 0)
+ return TIPC_OK;
- /* swap map */
- remains_tmp = remains;
- remains = remains_new;
- remains_new = remains_tmp;
+ bcbearer->remains = bcbearer->remains_new;
}
-
+
/* Unable to reach all targets */
bcbearer->bearer.publ.blocked = 1;
bcl->stats.bearer_congs++;
- err = ~TIPC_OK;
-
- out:
- kfree(remains_new);
- kfree(remains);
- return err;
+ return ~TIPC_OK;
}
/**
/**
* tipc_bcbearer_push - resolve bearer congestion
- *
+ *
* Forces bclink to push out any unsent packets, until all packets are gone
* or congestion reoccurs.
* No locks set when function called
spin_lock_bh(&bc_lock);
tipc_printf(&pb, "Link <%s>\n"
- " Window:%u packets\n",
+ " Window:%u packets\n",
bcl->name, bcl->queue_limit[0]);
- tipc_printf(&pb, " RX packets:%u fragments:%u/%u bundles:%u/%u\n",
+ tipc_printf(&pb, " RX packets:%u fragments:%u/%u bundles:%u/%u\n",
bcl->stats.recv_info,
bcl->stats.recv_fragments,
bcl->stats.recv_fragmented,
bcl->stats.recv_bundles,
bcl->stats.recv_bundled);
- tipc_printf(&pb, " TX packets:%u fragments:%u/%u bundles:%u/%u\n",
+ tipc_printf(&pb, " TX packets:%u fragments:%u/%u bundles:%u/%u\n",
bcl->stats.sent_info,
bcl->stats.sent_fragments,
- bcl->stats.sent_fragmented,
+ bcl->stats.sent_fragmented,
bcl->stats.sent_bundles,
bcl->stats.sent_bundled);
- tipc_printf(&pb, " RX naks:%u defs:%u dups:%u\n",
+ tipc_printf(&pb, " RX naks:%u defs:%u dups:%u\n",
bcl->stats.recv_nacks,
- bcl->stats.deferred_recv,
+ bcl->stats.deferred_recv,
bcl->stats.duplicates);
- tipc_printf(&pb, " TX naks:%u acks:%u dups:%u\n",
- bcl->stats.sent_nacks,
- bcl->stats.sent_acks,
+ tipc_printf(&pb, " TX naks:%u acks:%u dups:%u\n",
+ bcl->stats.sent_nacks,
+ bcl->stats.sent_acks,
bcl->stats.retransmitted);
tipc_printf(&pb, " Congestion bearer:%u link:%u Send queue max:%u avg:%u\n",
bcl->stats.bearer_congs,
int tipc_bclink_init(void)
{
- bcbearer = kmalloc(sizeof(*bcbearer), GFP_ATOMIC);
- bclink = kmalloc(sizeof(*bclink), GFP_ATOMIC);
+ bcbearer = kzalloc(sizeof(*bcbearer), GFP_ATOMIC);
+ bclink = kzalloc(sizeof(*bclink), GFP_ATOMIC);
if (!bcbearer || !bclink) {
nomem:
- warn("Memory squeeze; Failed to create multicast link\n");
+ warn("Multicast link creation failed, no memory\n");
kfree(bcbearer);
bcbearer = NULL;
kfree(bclink);
return -ENOMEM;
}
- memset(bcbearer, 0, sizeof(struct bcbearer));
INIT_LIST_HEAD(&bcbearer->bearer.cong_links);
bcbearer->bearer.media = &bcbearer->media;
bcbearer->media.send_msg = tipc_bcbearer_send;
sprintf(bcbearer->media.name, "tipc-multicast");
bcl = &bclink->link;
- memset(bclink, 0, sizeof(struct bclink));
INIT_LIST_HEAD(&bcl->waiting_ports);
bcl->next_out_no = 1;
- bclink->node.lock = SPIN_LOCK_UNLOCKED;
+ spin_lock_init(&bclink->node.lock);
bcl->owner = &bclink->node;
- bcl->max_pkt = MAX_PKT_DEFAULT_MCAST;
+ bcl->max_pkt = MAX_PKT_DEFAULT_MCAST;
tipc_link_set_queue_limits(bcl, BCLINK_WIN_DEFAULT);
bcl->b_ptr = &bcbearer->bearer;
bcl->state = WORKING_WORKING;
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff