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Commit 662921cd authored by Jon Paul Maloy's avatar Jon Paul Maloy Committed by David S. Miller
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tipc: merge link->exec_mode and link->state into one FSM 

Until now, we have been handling link failover and synchronization
by using an additional link state variable, "exec_mode". This variable
is not independent of the link FSM state, something causing a risk of
inconsistencies, apart from the fact that it clutters the code.

The conditions are now in place to define a new link FSM that covers
all existing use cases, including failover and synchronization, and
eliminate the "exec_mode" field altogether. The FSM must also support
non-atomic resetting of links, which will be introduced later.

The new link FSM is shown below, with 7 states and 8 events.
Only events leading to state change are shown as edges.

+------------------------------------+
|RESET_EVT                           |
|                                    |
|                             +--------------+
|           +-----------------|   SYNCHING   |-----------------+
|           |FAILURE_EVT      +--------------+   PEER_RESET_EVT|
|           |                  A            |                  |
|           |                  |            |                  |
|           |                  |            |                  |
|           |                  |SYNCH_      |SYNCH_            |
|           |                  |BEGIN_EVT   |END_EVT           |
|           |                  |            |                  |
|           V                  |            V                  V
|    +-------------+          +--------------+          +------------+
|    |  RESETTING  |<---------|  ESTABLISHED |--------->| PEER_RESET |
|    +-------------+ FAILURE_ +--------------+ PEER_    +------------+
|           |        EVT        |    A         RESET_EVT       |
|           |                   |    |                         |
|           |                   |    |                         |
|           |    +--------------+    |                         |
|  RESET_EVT|    |RESET_EVT          |ESTABLISH_EVT            |
|           |    |                   |                         |
|           |    |                   |                         |
|           V    V                   |                         |
|    +-------------+          +--------------+        RESET_EVT|
+--->|    RESET    |--------->| ESTABLISHING |<----------------+
     +-------------+ PEER_    +--------------+
      |           A  RESET_EVT       |
      |           |                  |
      |           |                  |
      |FAILOVER_  |FAILOVER_         |FAILOVER_
      |BEGIN_EVT  |END_EVT           |BEGIN_EVT
      |           |                  |
      V           |                  |
     +-------------+                 |
     | FAILINGOVER |<----------------+
     +-------------+

These changes are fully backwards compatible.
Tested-by: default avatarYing Xue <ying.xue@windriver.com>
Signed-off-by: default avatarJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 5045f7b9
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Showing with 226 additions and 180 deletions
net/tipc/link.c
View file @ 662921cd
...@@ -50,7 +50,6 @@ ...@@ -50,7 +50,6 @@
*/ */
static const char *link_co_err = "Link tunneling error, "; static const char *link_co_err = "Link tunneling error, ";
static const char *link_rst_msg = "Resetting link "; static const char *link_rst_msg = "Resetting link ";
static const char *link_unk_evt = "Unknown link event ";
static const struct nla_policy tipc_nl_link_policy[TIPC_NLA_LINK_MAX + 1] = { static const struct nla_policy tipc_nl_link_policy[TIPC_NLA_LINK_MAX + 1] = {
[TIPC_NLA_LINK_UNSPEC] = { .type = NLA_UNSPEC }, [TIPC_NLA_LINK_UNSPEC] = { .type = NLA_UNSPEC },
...@@ -85,46 +84,23 @@ static const struct nla_policy tipc_nl_prop_policy[TIPC_NLA_PROP_MAX + 1] = { ...@@ -85,46 +84,23 @@ static const struct nla_policy tipc_nl_prop_policy[TIPC_NLA_PROP_MAX + 1] = {
*/ */
#define WILDCARD_SESSION 0x10000 #define WILDCARD_SESSION 0x10000
/* State value stored in 'failover_pkts' /* Link FSM states:
*/ */
#define FIRST_FAILOVER 0xffffu
/* Link FSM states and events:
*/
enum {
TIPC_LINK_WORKING,
TIPC_LINK_PROBING,
TIPC_LINK_RESETTING,
TIPC_LINK_ESTABLISHING
};
enum { enum {
PEER_RESET_EVT = RESET_MSG, LINK_ESTABLISHED = 0xe,
ACTIVATE_EVT = ACTIVATE_MSG, LINK_ESTABLISHING = 0xe << 4,
TRAFFIC_EVT, /* Any other valid msg from peer */ LINK_RESET = 0x1 << 8,
SILENCE_EVT /* Peer was silent during last timer interval*/ LINK_RESETTING = 0x2 << 12,
LINK_PEER_RESET = 0xd << 16,
LINK_FAILINGOVER = 0xf << 20,
LINK_SYNCHING = 0xc << 24
}; };
/* Link FSM state checking routines /* Link FSM state checking routines
*/ */
static int link_working(struct tipc_link *l) static int link_is_up(struct tipc_link *l)
{
return l->state == TIPC_LINK_WORKING;
}
static int link_probing(struct tipc_link *l)
{
return l->state == TIPC_LINK_PROBING;
}
static int link_resetting(struct tipc_link *l)
{ {
return l->state == TIPC_LINK_RESETTING; return l->state & (LINK_ESTABLISHED | LINK_SYNCHING);
}
static int link_establishing(struct tipc_link *l)
{
return l->state == TIPC_LINK_ESTABLISHING;
} }
static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb, static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
...@@ -141,11 +117,29 @@ static bool tipc_data_input(struct tipc_link *l, struct sk_buff *skb); ...@@ -141,11 +117,29 @@ static bool tipc_data_input(struct tipc_link *l, struct sk_buff *skb);
/* /*
* Simple non-static link routines (i.e. referenced outside this file) * Simple non-static link routines (i.e. referenced outside this file)
*/ */
int tipc_link_is_up(struct tipc_link *l_ptr) bool tipc_link_is_up(struct tipc_link *l)
{ {
if (!l_ptr) return link_is_up(l);
return 0; }
return link_working(l_ptr) || link_probing(l_ptr);
bool tipc_link_is_reset(struct tipc_link *l)
{
return l->state & (LINK_RESET | LINK_FAILINGOVER | LINK_ESTABLISHING);
}
bool tipc_link_is_synching(struct tipc_link *l)
{
return l->state == LINK_SYNCHING;
}
bool tipc_link_is_failingover(struct tipc_link *l)
{
return l->state == LINK_FAILINGOVER;
}
bool tipc_link_is_blocked(struct tipc_link *l)
{
return l->state & (LINK_RESETTING | LINK_PEER_RESET | LINK_FAILINGOVER);
} }
int tipc_link_is_active(struct tipc_link *l) int tipc_link_is_active(struct tipc_link *l)
...@@ -210,7 +204,7 @@ struct tipc_link *tipc_link_create(struct tipc_node *n_ptr, ...@@ -210,7 +204,7 @@ struct tipc_link *tipc_link_create(struct tipc_node *n_ptr,
l_ptr->tolerance = b_ptr->tolerance; l_ptr->tolerance = b_ptr->tolerance;
l_ptr->snd_nxt = 1; l_ptr->snd_nxt = 1;
l_ptr->rcv_nxt = 1; l_ptr->rcv_nxt = 1;
l_ptr->state = TIPC_LINK_RESETTING; l_ptr->state = LINK_RESET;
l_ptr->pmsg = (struct tipc_msg *)&l_ptr->proto_msg; l_ptr->pmsg = (struct tipc_msg *)&l_ptr->proto_msg;
msg = l_ptr->pmsg; msg = l_ptr->pmsg;
...@@ -265,120 +259,159 @@ void tipc_link_build_bcast_sync_msg(struct tipc_link *l, ...@@ -265,120 +259,159 @@ void tipc_link_build_bcast_sync_msg(struct tipc_link *l,
* tipc_link_fsm_evt - link finite state machine * tipc_link_fsm_evt - link finite state machine
* @l: pointer to link * @l: pointer to link
* @evt: state machine event to be processed * @evt: state machine event to be processed
* @xmitq: queue to prepend created protocol message, if any
*/ */
static int tipc_link_fsm_evt(struct tipc_link *l, int evt, int tipc_link_fsm_evt(struct tipc_link *l, int evt)
struct sk_buff_head *xmitq)
{ {
int rc = 0; int rc = 0;
struct tipc_link *pl;
enum {
LINK_RESET = 1,
LINK_ACTIVATE = (1 << 1),
SND_PROBE = (1 << 2),
SND_STATE = (1 << 3),
SND_RESET = (1 << 4),
SND_ACTIVATE = (1 << 5),
SND_BCAST_SYNC = (1 << 6)
} actions = 0;
if (l->exec_mode == TIPC_LINK_BLOCKED)
return rc;
switch (l->state) { switch (l->state) {
case TIPC_LINK_WORKING: case LINK_RESETTING:
switch (evt) { switch (evt) {
case TRAFFIC_EVT: case LINK_PEER_RESET_EVT:
case ACTIVATE_EVT: l->state = LINK_PEER_RESET;
break;
case LINK_RESET_EVT:
l->state = LINK_RESET;
break;
case LINK_FAILURE_EVT:
case LINK_FAILOVER_BEGIN_EVT:
case LINK_ESTABLISH_EVT:
case LINK_FAILOVER_END_EVT:
case LINK_SYNCH_BEGIN_EVT:
case LINK_SYNCH_END_EVT:
default:
goto illegal_evt;
}
break; break;
case SILENCE_EVT: case LINK_RESET:
l->state = TIPC_LINK_PROBING; switch (evt) {
actions |= SND_PROBE; case LINK_PEER_RESET_EVT:
l->state = LINK_ESTABLISHING;
break; break;
case PEER_RESET_EVT: case LINK_FAILOVER_BEGIN_EVT:
actions |= LINK_RESET | SND_ACTIVATE; l->state = LINK_FAILINGOVER;
case LINK_FAILURE_EVT:
case LINK_RESET_EVT:
case LINK_ESTABLISH_EVT:
case LINK_FAILOVER_END_EVT:
break; break;
case LINK_SYNCH_BEGIN_EVT:
case LINK_SYNCH_END_EVT:
default: default:
pr_debug("%s%u WORKING\n", link_unk_evt, evt); goto illegal_evt;
} }
break; break;
case TIPC_LINK_PROBING: case LINK_PEER_RESET:
switch (evt) { switch (evt) {
case TRAFFIC_EVT: case LINK_RESET_EVT:
case ACTIVATE_EVT: l->state = LINK_ESTABLISHING;
l->state = TIPC_LINK_WORKING; break;
case LINK_PEER_RESET_EVT:
case LINK_ESTABLISH_EVT:
case LINK_FAILURE_EVT:
break;
case LINK_SYNCH_BEGIN_EVT:
case LINK_SYNCH_END_EVT:
case LINK_FAILOVER_BEGIN_EVT:
case LINK_FAILOVER_END_EVT:
default:
goto illegal_evt;
}
break; break;
case PEER_RESET_EVT: case LINK_FAILINGOVER:
actions |= LINK_RESET | SND_ACTIVATE; switch (evt) {
case LINK_FAILOVER_END_EVT:
l->state = LINK_RESET;
break; break;
case SILENCE_EVT: case LINK_PEER_RESET_EVT:
if (l->silent_intv_cnt <= l->abort_limit) { case LINK_RESET_EVT:
actions |= SND_PROBE; case LINK_ESTABLISH_EVT:
case LINK_FAILURE_EVT:
break; break;
case LINK_FAILOVER_BEGIN_EVT:
case LINK_SYNCH_BEGIN_EVT:
case LINK_SYNCH_END_EVT:
default:
goto illegal_evt;
} }
actions |= LINK_RESET | SND_RESET;
break; break;
case LINK_ESTABLISHING:
switch (evt) {
case LINK_ESTABLISH_EVT:
l->state = LINK_ESTABLISHED;
rc |= TIPC_LINK_UP_EVT;
break;
case LINK_FAILOVER_BEGIN_EVT:
l->state = LINK_FAILINGOVER;
break;
case LINK_PEER_RESET_EVT:
case LINK_RESET_EVT:
case LINK_FAILURE_EVT:
case LINK_SYNCH_BEGIN_EVT:
case LINK_FAILOVER_END_EVT:
break;
case LINK_SYNCH_END_EVT:
default: default:
pr_err("%s%u PROBING\n", link_unk_evt, evt); goto illegal_evt;
} }
break; break;
case TIPC_LINK_RESETTING: case LINK_ESTABLISHED:
switch (evt) { switch (evt) {
case TRAFFIC_EVT: case LINK_PEER_RESET_EVT:
l->state = LINK_PEER_RESET;
rc |= TIPC_LINK_DOWN_EVT;
break; break;
case ACTIVATE_EVT: case LINK_FAILURE_EVT:
pl = node_active_link(l->owner, 0); l->state = LINK_RESETTING;
if (pl && link_probing(pl)) rc |= TIPC_LINK_DOWN_EVT;
break; break;
l->state = TIPC_LINK_WORKING; case LINK_RESET_EVT:
actions |= LINK_ACTIVATE; l->state = LINK_RESET;
if (!l->owner->working_links)
actions |= SND_BCAST_SYNC;
break; break;
case PEER_RESET_EVT: case LINK_ESTABLISH_EVT:
l->state = TIPC_LINK_ESTABLISHING;
actions |= SND_ACTIVATE;
break; break;
case SILENCE_EVT: case LINK_SYNCH_BEGIN_EVT:
actions |= SND_RESET; l->state = LINK_SYNCHING;
break; break;
case LINK_SYNCH_END_EVT:
case LINK_FAILOVER_BEGIN_EVT:
case LINK_FAILOVER_END_EVT:
default: default:
pr_err("%s%u in RESETTING\n", link_unk_evt, evt); goto illegal_evt;
} }
break; break;
case TIPC_LINK_ESTABLISHING: case LINK_SYNCHING:
switch (evt) { switch (evt) {
case TRAFFIC_EVT: case LINK_PEER_RESET_EVT:
case ACTIVATE_EVT: l->state = LINK_PEER_RESET;
pl = node_active_link(l->owner, 0); rc |= TIPC_LINK_DOWN_EVT;
if (pl && link_probing(pl)) break;
case LINK_FAILURE_EVT:
l->state = LINK_RESETTING;
rc |= TIPC_LINK_DOWN_EVT;
break; break;
l->state = TIPC_LINK_WORKING; case LINK_RESET_EVT:
actions |= LINK_ACTIVATE; l->state = LINK_RESET;
if (!l->owner->working_links)
actions |= SND_BCAST_SYNC;
break; break;
case PEER_RESET_EVT: case LINK_ESTABLISH_EVT:
case LINK_SYNCH_BEGIN_EVT:
break; break;
case SILENCE_EVT: case LINK_SYNCH_END_EVT:
actions |= SND_ACTIVATE; l->state = LINK_ESTABLISHED;
break; break;
case LINK_FAILOVER_BEGIN_EVT:
case LINK_FAILOVER_END_EVT:
default: default:
pr_err("%s%u ESTABLISHING\n", link_unk_evt, evt); goto illegal_evt;
} }
break; break;
default: default:
pr_err("Unknown link state %u/%u\n", l->state, evt); pr_err("Unknown FSM state %x in %s\n", l->state, l->name);
}
/* Perform actions as decided by FSM */
if (actions & LINK_RESET) {
l->exec_mode = TIPC_LINK_BLOCKED;
rc = TIPC_LINK_DOWN_EVT;
} }
if (actions & LINK_ACTIVATE) return rc;
rc = TIPC_LINK_UP_EVT; illegal_evt:
pr_err("Illegal FSM event %x in state %x on link %s\n",
evt, l->state, l->name);
return rc; return rc;
} }
...@@ -432,12 +465,11 @@ int tipc_link_timeout(struct tipc_link *l, struct sk_buff_head *xmitq) ...@@ -432,12 +465,11 @@ int tipc_link_timeout(struct tipc_link *l, struct sk_buff_head *xmitq)
bool xmit = false; bool xmit = false;
bool prb = false; bool prb = false;
if (l->exec_mode == TIPC_LINK_BLOCKED)
return rc;
link_profile_stats(l); link_profile_stats(l);
if (l->state == TIPC_LINK_WORKING) { switch (l->state) {
case LINK_ESTABLISHED:
case LINK_SYNCHING:
if (!l->silent_intv_cnt) { if (!l->silent_intv_cnt) {
if (tipc_bclink_acks_missing(l->owner)) if (tipc_bclink_acks_missing(l->owner))
xmit = true; xmit = true;
...@@ -445,17 +477,26 @@ int tipc_link_timeout(struct tipc_link *l, struct sk_buff_head *xmitq) ...@@ -445,17 +477,26 @@ int tipc_link_timeout(struct tipc_link *l, struct sk_buff_head *xmitq)
xmit = true; xmit = true;
prb = true; prb = true;
} else { } else {
l->exec_mode = TIPC_LINK_BLOCKED; rc |= tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
rc |= TIPC_LINK_DOWN_EVT;
} }
l->silent_intv_cnt++; l->silent_intv_cnt++;
} else if (l->state == TIPC_LINK_RESETTING) { break;
case LINK_RESET:
xmit = true; xmit = true;
mtyp = RESET_MSG; mtyp = RESET_MSG;
} else if (l->state == TIPC_LINK_ESTABLISHING) { break;
case LINK_ESTABLISHING:
xmit = true; xmit = true;
mtyp = ACTIVATE_MSG; mtyp = ACTIVATE_MSG;
break;
case LINK_RESETTING:
case LINK_PEER_RESET:
case LINK_FAILINGOVER:
break;
default:
break;
} }
if (xmit) if (xmit)
tipc_link_build_proto_msg(l, mtyp, prb, 0, 0, 0, xmitq); tipc_link_build_proto_msg(l, mtyp, prb, 0, 0, 0, xmitq);
...@@ -559,7 +600,7 @@ void tipc_link_reset(struct tipc_link *l) ...@@ -559,7 +600,7 @@ void tipc_link_reset(struct tipc_link *l)
{ {
struct tipc_node *owner = l->owner; struct tipc_node *owner = l->owner;
l->state = TIPC_LINK_RESETTING; tipc_link_fsm_evt(l, LINK_RESET_EVT);
/* Link is down, accept any session */ /* Link is down, accept any session */
l->peer_session = WILDCARD_SESSION; l->peer_session = WILDCARD_SESSION;
...@@ -902,8 +943,7 @@ static int tipc_link_retransm(struct tipc_link *l, int retransm, ...@@ -902,8 +943,7 @@ static int tipc_link_retransm(struct tipc_link *l, int retransm,
l->stale_count = 1; l->stale_count = 1;
} else if (++l->stale_count > 100) { } else if (++l->stale_count > 100) {
link_retransmit_failure(l, skb); link_retransmit_failure(l, skb);
l->exec_mode = TIPC_LINK_BLOCKED; return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
return TIPC_LINK_DOWN_EVT;
} }
skb_queue_walk(&l->transmq, skb) { skb_queue_walk(&l->transmq, skb) {
if (!retransm) if (!retransm)
...@@ -1002,25 +1042,23 @@ static int tipc_link_input(struct tipc_link *l, struct sk_buff *skb) ...@@ -1002,25 +1042,23 @@ static int tipc_link_input(struct tipc_link *l, struct sk_buff *skb)
l->stats.recv_bundled += msg_msgcnt(hdr); l->stats.recv_bundled += msg_msgcnt(hdr);
while (tipc_msg_extract(skb, &iskb, &pos)) while (tipc_msg_extract(skb, &iskb, &pos))
tipc_data_input(l, iskb); tipc_data_input(l, iskb);
return rc; return 0;
} else if (usr == MSG_FRAGMENTER) { } else if (usr == MSG_FRAGMENTER) {
l->stats.recv_fragments++; l->stats.recv_fragments++;
if (tipc_buf_append(reasm_skb, &skb)) { if (tipc_buf_append(reasm_skb, &skb)) {
l->stats.recv_fragmented++; l->stats.recv_fragmented++;
tipc_data_input(l, skb); tipc_data_input(l, skb);
} else if (!*reasm_skb) { } else if (!*reasm_skb) {
l->exec_mode = TIPC_LINK_BLOCKED; return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
l->state = TIPC_LINK_RESETTING;
rc = TIPC_LINK_DOWN_EVT;
} }
return rc; return 0;
} else if (usr == BCAST_PROTOCOL) { } else if (usr == BCAST_PROTOCOL) {
tipc_link_sync_rcv(node, skb); tipc_link_sync_rcv(node, skb);
return rc; return 0;
} }
drop: drop:
kfree_skb(skb); kfree_skb(skb);
return rc; return 0;
} }
static bool tipc_link_release_pkts(struct tipc_link *l, u16 acked) static bool tipc_link_release_pkts(struct tipc_link *l, u16 acked)
...@@ -1068,9 +1106,9 @@ int tipc_link_rcv(struct tipc_link *l, struct sk_buff *skb, ...@@ -1068,9 +1106,9 @@ int tipc_link_rcv(struct tipc_link *l, struct sk_buff *skb,
continue; continue;
} }
if (unlikely(!link_working(l))) { if (unlikely(!link_is_up(l))) {
rc = tipc_link_fsm_evt(l, TRAFFIC_EVT, xmitq); rc = tipc_link_fsm_evt(l, LINK_ESTABLISH_EVT);
if (!link_working(l)) { if (!link_is_up(l)) {
kfree_skb(__skb_dequeue(arrvq)); kfree_skb(__skb_dequeue(arrvq));
return rc; return rc;
} }
...@@ -1192,7 +1230,7 @@ static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe, ...@@ -1192,7 +1230,7 @@ static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe,
int node_up = l->owner->bclink.recv_permitted; int node_up = l->owner->bclink.recv_permitted;
/* Don't send protocol message during reset or link failover */ /* Don't send protocol message during reset or link failover */
if (l->exec_mode == TIPC_LINK_BLOCKED) if (tipc_link_is_blocked(l))
return; return;
msg_set_type(hdr, mtyp); msg_set_type(hdr, mtyp);
...@@ -1302,7 +1340,6 @@ void tipc_link_tnl_prepare(struct tipc_link *l, struct tipc_link *tnl, ...@@ -1302,7 +1340,6 @@ void tipc_link_tnl_prepare(struct tipc_link *l, struct tipc_link *tnl,
tnl->drop_point = l->rcv_nxt; tnl->drop_point = l->rcv_nxt;
tnl->failover_reasm_skb = l->reasm_buf; tnl->failover_reasm_skb = l->reasm_buf;
l->reasm_buf = NULL; l->reasm_buf = NULL;
l->exec_mode = TIPC_LINK_BLOCKED;
} }
} }
...@@ -1323,7 +1360,7 @@ static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb, ...@@ -1323,7 +1360,7 @@ static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
char *if_name; char *if_name;
int rc = 0; int rc = 0;
if (l->exec_mode == TIPC_LINK_BLOCKED) if (tipc_link_is_blocked(l))
goto exit; goto exit;
if (link_own_addr(l) > msg_prevnode(hdr)) if (link_own_addr(l) > msg_prevnode(hdr))
...@@ -1337,6 +1374,7 @@ static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb, ...@@ -1337,6 +1374,7 @@ static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
(l->peer_session != WILDCARD_SESSION)) (l->peer_session != WILDCARD_SESSION))
break; break;
/* fall thru' */ /* fall thru' */
case ACTIVATE_MSG: case ACTIVATE_MSG:
/* Complete own link name with peer's interface name */ /* Complete own link name with peer's interface name */
...@@ -1355,13 +1393,20 @@ static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb, ...@@ -1355,13 +1393,20 @@ static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
if (in_range(peers_prio, l->priority + 1, TIPC_MAX_LINK_PRI)) if (in_range(peers_prio, l->priority + 1, TIPC_MAX_LINK_PRI))
l->priority = peers_prio; l->priority = peers_prio;
if (msg_type(hdr) == RESET_MSG) {
rc |= tipc_link_fsm_evt(l, LINK_PEER_RESET_EVT);
} else if (!link_is_up(l)) {
tipc_link_fsm_evt(l, LINK_PEER_RESET_EVT);
rc |= tipc_link_fsm_evt(l, LINK_ESTABLISH_EVT);
}
l->peer_session = msg_session(hdr); l->peer_session = msg_session(hdr);
l->peer_bearer_id = msg_bearer_id(hdr); l->peer_bearer_id = msg_bearer_id(hdr);
rc = tipc_link_fsm_evt(l, msg_type(hdr), xmitq);
if (l->mtu > msg_max_pkt(hdr)) if (l->mtu > msg_max_pkt(hdr))
l->mtu = msg_max_pkt(hdr); l->mtu = msg_max_pkt(hdr);
break; break;
case STATE_MSG: case STATE_MSG:
/* Update own tolerance if peer indicates a non-zero value */ /* Update own tolerance if peer indicates a non-zero value */
if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL)) if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL))
l->tolerance = peers_tol; l->tolerance = peers_tol;
...@@ -1370,11 +1415,11 @@ static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb, ...@@ -1370,11 +1415,11 @@ static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
l->stats.recv_states++; l->stats.recv_states++;
if (msg_probe(hdr)) if (msg_probe(hdr))
l->stats.recv_probes++; l->stats.recv_probes++;
rc = tipc_link_fsm_evt(l, TRAFFIC_EVT, xmitq); rc = tipc_link_fsm_evt(l, LINK_ESTABLISH_EVT);
if (!tipc_link_is_up(l)) if (!link_is_up(l))
break; break;
/* Has peer sent packets we haven't received yet ? */ /* Send NACK if peer has sent pkts we haven't received yet */
if (more(peers_snd_nxt, l->rcv_nxt)) if (more(peers_snd_nxt, l->rcv_nxt))
rcvgap = peers_snd_nxt - l->rcv_nxt; rcvgap = peers_snd_nxt - l->rcv_nxt;
if (rcvgap || (msg_probe(hdr))) if (rcvgap || (msg_probe(hdr)))
...@@ -1387,6 +1432,7 @@ static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb, ...@@ -1387,6 +1432,7 @@ static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
rc = tipc_link_retransm(l, nacked_gap, xmitq); rc = tipc_link_retransm(l, nacked_gap, xmitq);
l->stats.recv_nacks++; l->stats.recv_nacks++;
} }
tipc_link_advance_backlog(l, xmitq); tipc_link_advance_backlog(l, xmitq);
if (unlikely(!skb_queue_empty(&l->wakeupq))) if (unlikely(!skb_queue_empty(&l->wakeupq)))
link_prepare_wakeup(l); link_prepare_wakeup(l);
...@@ -1463,19 +1509,7 @@ static void link_print(struct tipc_link *l, const char *str) ...@@ -1463,19 +1509,7 @@ static void link_print(struct tipc_link *l, const char *str)
u16 head = hskb ? msg_seqno(buf_msg(hskb)) : l->snd_nxt; u16 head = hskb ? msg_seqno(buf_msg(hskb)) : l->snd_nxt;
u16 tail = l->snd_nxt - 1; u16 tail = l->snd_nxt - 1;
pr_info("%s Link <%s>:", str, l->name); pr_info("%s Link <%s> state %x\n", str, l->name, l->state);
if (link_probing(l))
pr_cont(":P\n");
else if (link_establishing(l))
pr_cont(":E\n");
else if (link_resetting(l))
pr_cont(":R\n");
else if (link_working(l))
pr_cont(":W\n");
else
pr_cont("\n");
pr_info("XMTQ: %u [%u-%u], BKLGQ: %u, SNDNX: %u, RCVNX: %u\n", pr_info("XMTQ: %u [%u-%u], BKLGQ: %u, SNDNX: %u, RCVNX: %u\n",
skb_queue_len(&l->transmq), head, tail, skb_queue_len(&l->transmq), head, tail,
skb_queue_len(&l->backlogq), l->snd_nxt, l->rcv_nxt); skb_queue_len(&l->backlogq), l->snd_nxt, l->rcv_nxt);
......
net/tipc/link.h
View file @ 662921cd
...@@ -49,13 +49,17 @@ ...@@ -49,13 +49,17 @@
*/ */
#define INVALID_LINK_SEQ 0x10000 #define INVALID_LINK_SEQ 0x10000
/* Link FSM events:
/* Link endpoint receive states
*/ */
enum { enum {
TIPC_LINK_OPEN, LINK_ESTABLISH_EVT = 0xec1ab1e,
TIPC_LINK_BLOCKED, LINK_PEER_RESET_EVT = 0x9eed0e,
TIPC_LINK_TUNNEL LINK_FAILURE_EVT = 0xfa110e,
LINK_RESET_EVT = 0x10ca1d0e,
LINK_FAILOVER_BEGIN_EVT = 0xfa110bee,
LINK_FAILOVER_END_EVT = 0xfa110ede,
LINK_SYNCH_BEGIN_EVT = 0xc1ccbee,
LINK_SYNCH_END_EVT = 0xc1ccede
}; };
/* Events returned from link at packet reception or at timeout /* Events returned from link at packet reception or at timeout
...@@ -120,7 +124,6 @@ struct tipc_stats { ...@@ -120,7 +124,6 @@ struct tipc_stats {
* @pmsg: convenience pointer to "proto_msg" field * @pmsg: convenience pointer to "proto_msg" field
* @priority: current link priority * @priority: current link priority
* @net_plane: current link network plane ('A' through 'H') * @net_plane: current link network plane ('A' through 'H')
* @exec_mode: transmit/receive mode for link endpoint instance
* @backlog_limit: backlog queue congestion thresholds (indexed by importance) * @backlog_limit: backlog queue congestion thresholds (indexed by importance)
* @exp_msg_count: # of tunnelled messages expected during link changeover * @exp_msg_count: # of tunnelled messages expected during link changeover
* @reset_rcv_checkpt: seq # of last acknowledged message at time of link reset * @reset_rcv_checkpt: seq # of last acknowledged message at time of link reset
...@@ -155,7 +158,7 @@ struct tipc_link { ...@@ -155,7 +158,7 @@ struct tipc_link {
u32 tolerance; u32 tolerance;
unsigned long keepalive_intv; unsigned long keepalive_intv;
u32 abort_limit; u32 abort_limit;
int state; u32 state;
u32 silent_intv_cnt; u32 silent_intv_cnt;
struct { struct {
unchar hdr[INT_H_SIZE]; unchar hdr[INT_H_SIZE];
...@@ -166,7 +169,6 @@ struct tipc_link { ...@@ -166,7 +169,6 @@ struct tipc_link {
char net_plane; char net_plane;
/* Failover/synch */ /* Failover/synch */
u8 exec_mode;
u16 drop_point; u16 drop_point;
struct sk_buff *failover_reasm_skb; struct sk_buff *failover_reasm_skb;
...@@ -214,8 +216,13 @@ void tipc_link_tnl_prepare(struct tipc_link *l, struct tipc_link *tnl, ...@@ -214,8 +216,13 @@ void tipc_link_tnl_prepare(struct tipc_link *l, struct tipc_link *tnl,
int mtyp, struct sk_buff_head *xmitq); int mtyp, struct sk_buff_head *xmitq);
void tipc_link_build_bcast_sync_msg(struct tipc_link *l, void tipc_link_build_bcast_sync_msg(struct tipc_link *l,
struct sk_buff_head *xmitq); struct sk_buff_head *xmitq);
int tipc_link_fsm_evt(struct tipc_link *l, int evt);
void tipc_link_reset_fragments(struct tipc_link *l_ptr); void tipc_link_reset_fragments(struct tipc_link *l_ptr);
int tipc_link_is_up(struct tipc_link *l_ptr); bool tipc_link_is_up(struct tipc_link *l);
bool tipc_link_is_reset(struct tipc_link *l);
bool tipc_link_is_synching(struct tipc_link *l);
bool tipc_link_is_failingover(struct tipc_link *l);
bool tipc_link_is_blocked(struct tipc_link *l);
int tipc_link_is_active(struct tipc_link *l_ptr); int tipc_link_is_active(struct tipc_link *l_ptr);
void tipc_link_purge_queues(struct tipc_link *l_ptr); void tipc_link_purge_queues(struct tipc_link *l_ptr);
void tipc_link_purge_backlog(struct tipc_link *l); void tipc_link_purge_backlog(struct tipc_link *l);
......
net/tipc/node.c
View file @ 662921cd
...@@ -334,7 +334,6 @@ static void tipc_node_link_up(struct tipc_node *n, int bearer_id, ...@@ -334,7 +334,6 @@ static void tipc_node_link_up(struct tipc_node *n, int bearer_id,
if (!ol) { if (!ol) {
*slot0 = bearer_id; *slot0 = bearer_id;
*slot1 = bearer_id; *slot1 = bearer_id;
nl->exec_mode = TIPC_LINK_OPEN;
tipc_link_build_bcast_sync_msg(nl, xmitq); tipc_link_build_bcast_sync_msg(nl, xmitq);
node_established_contact(n); node_established_contact(n);
return; return;
...@@ -368,7 +367,7 @@ static void tipc_node_link_down(struct tipc_node *n, int bearer_id) ...@@ -368,7 +367,7 @@ static void tipc_node_link_down(struct tipc_node *n, int bearer_id)
struct sk_buff_head xmitq; struct sk_buff_head xmitq;
l = n->links[bearer_id].link; l = n->links[bearer_id].link;
if (!l || !tipc_link_is_up(l)) if (!l || tipc_link_is_reset(l))
return; return;
__skb_queue_head_init(&xmitq); __skb_queue_head_init(&xmitq);
...@@ -414,6 +413,7 @@ static void tipc_node_link_down(struct tipc_node *n, int bearer_id) ...@@ -414,6 +413,7 @@ static void tipc_node_link_down(struct tipc_node *n, int bearer_id)
n->sync_point = tnl->rcv_nxt + (U16_MAX / 2 - 1); n->sync_point = tnl->rcv_nxt + (U16_MAX / 2 - 1);
tipc_link_tnl_prepare(l, tnl, FAILOVER_MSG, &xmitq); tipc_link_tnl_prepare(l, tnl, FAILOVER_MSG, &xmitq);
tipc_link_reset(l); tipc_link_reset(l);
tipc_link_fsm_evt(l, LINK_FAILOVER_BEGIN_EVT);
tipc_bearer_xmit(n->net, tnl->bearer_id, &xmitq, maddr); tipc_bearer_xmit(n->net, tnl->bearer_id, &xmitq, maddr);
} }
...@@ -749,7 +749,7 @@ static void node_lost_contact(struct tipc_node *n_ptr) ...@@ -749,7 +749,7 @@ static void node_lost_contact(struct tipc_node *n_ptr)
struct tipc_link *l_ptr = n_ptr->links[i].link; struct tipc_link *l_ptr = n_ptr->links[i].link;
if (!l_ptr) if (!l_ptr)
continue; continue;
l_ptr->exec_mode = TIPC_LINK_OPEN; tipc_link_fsm_evt(l_ptr, LINK_FAILOVER_END_EVT);
kfree_skb(l_ptr->failover_reasm_skb); kfree_skb(l_ptr->failover_reasm_skb);
l_ptr->failover_reasm_skb = NULL; l_ptr->failover_reasm_skb = NULL;
tipc_link_reset_fragments(l_ptr); tipc_link_reset_fragments(l_ptr);
...@@ -989,7 +989,7 @@ int tipc_node_xmit_skb(struct net *net, struct sk_buff *skb, u32 dnode, ...@@ -989,7 +989,7 @@ int tipc_node_xmit_skb(struct net *net, struct sk_buff *skb, u32 dnode,
* Returns true if state is ok, otherwise consumes buffer and returns false * Returns true if state is ok, otherwise consumes buffer and returns false
*/ */
static bool tipc_node_check_state(struct tipc_node *n, struct sk_buff *skb, static bool tipc_node_check_state(struct tipc_node *n, struct sk_buff *skb,
int bearer_id) int bearer_id, struct sk_buff_head *xmitq)
{ {
struct tipc_msg *hdr = buf_msg(skb); struct tipc_msg *hdr = buf_msg(skb);
int usr = msg_user(hdr); int usr = msg_user(hdr);
...@@ -1042,42 +1042,47 @@ static bool tipc_node_check_state(struct tipc_node *n, struct sk_buff *skb, ...@@ -1042,42 +1042,47 @@ static bool tipc_node_check_state(struct tipc_node *n, struct sk_buff *skb,
/* Initiate or update failover mode if applicable */ /* Initiate or update failover mode if applicable */
if ((usr == TUNNEL_PROTOCOL) && (mtyp == FAILOVER_MSG)) { if ((usr == TUNNEL_PROTOCOL) && (mtyp == FAILOVER_MSG)) {
syncpt = oseqno + exp_pkts - 1; syncpt = oseqno + exp_pkts - 1;
if (pl && tipc_link_is_up(pl)) { if (pl && tipc_link_is_up(pl))
tipc_node_link_down(n, pl->bearer_id); tipc_node_link_down(n, pl->bearer_id);
pl->exec_mode = TIPC_LINK_BLOCKED;
}
/* If pkts arrive out of order, use lowest calculated syncpt */ /* If pkts arrive out of order, use lowest calculated syncpt */
if (less(syncpt, n->sync_point)) if (less(syncpt, n->sync_point))
n->sync_point = syncpt; n->sync_point = syncpt;
} }
/* Open parallel link when tunnel link reaches synch point */ /* Open parallel link when tunnel link reaches synch point */
if ((n->state == NODE_FAILINGOVER) && (more(rcv_nxt, n->sync_point))) { if ((n->state == NODE_FAILINGOVER) && !tipc_link_is_failingover(l)) {
if (!more(rcv_nxt, n->sync_point))
return true;
tipc_node_fsm_evt(n, NODE_FAILOVER_END_EVT); tipc_node_fsm_evt(n, NODE_FAILOVER_END_EVT);
if (pl) if (pl)
pl->exec_mode = TIPC_LINK_OPEN; tipc_link_fsm_evt(pl, LINK_FAILOVER_END_EVT);
return true; return true;
} }
/* Initiate or update synch mode if applicable */ /* Initiate or update synch mode if applicable */
if ((usr == TUNNEL_PROTOCOL) && (mtyp == SYNCH_MSG)) { if ((usr == TUNNEL_PROTOCOL) && (mtyp == SYNCH_MSG)) {
syncpt = iseqno + exp_pkts - 1; syncpt = iseqno + exp_pkts - 1;
if (!tipc_link_is_up(l)) {
tipc_link_fsm_evt(l, LINK_ESTABLISH_EVT);
tipc_node_link_up(n, bearer_id, xmitq);
}
if (n->state == SELF_UP_PEER_UP) { if (n->state == SELF_UP_PEER_UP) {
n->sync_point = syncpt; n->sync_point = syncpt;
tipc_link_fsm_evt(l, LINK_SYNCH_BEGIN_EVT);
tipc_node_fsm_evt(n, NODE_SYNCH_BEGIN_EVT); tipc_node_fsm_evt(n, NODE_SYNCH_BEGIN_EVT);
} }
l->exec_mode = TIPC_LINK_TUNNEL;
if (less(syncpt, n->sync_point)) if (less(syncpt, n->sync_point))
n->sync_point = syncpt; n->sync_point = syncpt;
} }
/* Open tunnel link when parallel link reaches synch point */ /* Open tunnel link when parallel link reaches synch point */
if ((n->state == NODE_SYNCHING) && (l->exec_mode == TIPC_LINK_TUNNEL)) { if ((n->state == NODE_SYNCHING) && tipc_link_is_synching(l)) {
if (pl) if (pl)
dlv_nxt = mod(pl->rcv_nxt - skb_queue_len(pl->inputq)); dlv_nxt = mod(pl->rcv_nxt - skb_queue_len(pl->inputq));
if (!pl || more(dlv_nxt, n->sync_point)) { if (!pl || more(dlv_nxt, n->sync_point)) {
tipc_link_fsm_evt(l, LINK_SYNCH_END_EVT);
tipc_node_fsm_evt(n, NODE_SYNCH_END_EVT); tipc_node_fsm_evt(n, NODE_SYNCH_END_EVT);
l->exec_mode = TIPC_LINK_OPEN;
return true; return true;
} }
if ((usr == TUNNEL_PROTOCOL) && (mtyp == SYNCH_MSG)) if ((usr == TUNNEL_PROTOCOL) && (mtyp == SYNCH_MSG))
...@@ -1143,7 +1148,7 @@ void tipc_rcv(struct net *net, struct sk_buff *skb, struct tipc_bearer *b) ...@@ -1143,7 +1148,7 @@ void tipc_rcv(struct net *net, struct sk_buff *skb, struct tipc_bearer *b)
tipc_bclink_acknowledge(n, msg_bcast_ack(hdr)); tipc_bclink_acknowledge(n, msg_bcast_ack(hdr));
/* Check and if necessary update node state */ /* Check and if necessary update node state */
if (likely(tipc_node_check_state(n, skb, bearer_id))) { if (likely(tipc_node_check_state(n, skb, bearer_id, &xmitq))) {
rc = tipc_link_rcv(le->link, skb, &xmitq); rc = tipc_link_rcv(le->link, skb, &xmitq);
skb = NULL; skb = NULL;
} }
......
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