From 67bd949a520151a5ab50090d02617adc4960868c Mon Sep 17 00:00:00 2001 From: Martin Mares Date: Thu, 11 Feb 1999 22:59:06 +0000 Subject: Real implementation of protocol state machines. Delayed startup/shutdown should work now. Initial feeding of protocols by interfaces/routes is done from the event queue to prevent unwanted recursion. --- nest/proto.c | 167 +++++++++++++++++++++++++++++++++++++++++++++++++---------- 1 file changed, 141 insertions(+), 26 deletions(-) (limited to 'nest/proto.c') diff --git a/nest/proto.c b/nest/proto.c index 976a967..c7c21dd 100644 --- a/nest/proto.c +++ b/nest/proto.c @@ -14,26 +14,45 @@ #include "nest/protocol.h" #include "lib/resource.h" #include "lib/lists.h" +#include "lib/event.h" #include "conf/conf.h" #include "nest/route.h" #include "nest/iface.h" +static pool *proto_pool; + list protocol_list; list proto_list; -list inactive_proto_list; + +static list inactive_proto_list; +static list initial_proto_list; + +static char *p_states[] = { "DOWN", "START", "UP", "STOP" }; +static char *c_states[] = { "HUNGRY", "FEEDING", "HAPPY", "FLUSHING" }; + +static void +proto_relink(struct proto *p) +{ + rem_node(&p->n); + add_tail(p->core_state == FS_HAPPY ? &proto_list : &inactive_proto_list, &p->n); +} void * proto_new(struct proto_config *c, unsigned size) { struct protocol *pr = c->proto; - struct proto *p = cfg_allocz(size); /* FIXME: Allocate from global pool */ + pool *r = rp_new(proto_pool, c->name); + struct proto *p = mb_alloc(r, size); p->cf = c; p->debug = c->debug; + p->name = c->name; p->preference = c->preference; p->disabled = c->disabled; p->proto = pr; - p->pool = rp_new(&root_pool, c->name); + p->pool = r; + p->attn = ev_new(r); + p->attn->data = p; return p; } @@ -57,6 +76,7 @@ protos_preconfig(struct config *c) init_list(&proto_list); init_list(&inactive_proto_list); + init_list(&initial_proto_list); debug("Protocol preconfig:"); WALK_LIST(p, protocol_list) { @@ -97,27 +117,45 @@ protos_commit(struct config *c) debug(" %s", x->name); p = x->proto; q = p->init(x); - add_tail(&inactive_proto_list, &q->n); + q->proto_state = PS_DOWN; + q->core_state = FS_HUNGRY; + add_tail(&initial_proto_list, &q->n); } debug("\n"); } static void -proto_start(struct proto *p) +proto_rethink_goal(struct proto *p) { - rem_node(&p->n); - if (p->disabled) + struct protocol *q = p->proto; + + if (p->core_state == p->core_goal) return; - p->proto_state = PS_DOWN; - p->core_state = FS_HUNGRY; - if (p->proto->start && p->proto->start(p) != PS_UP) - bug("Delayed protocol start not supported yet"); - p->proto_state = PS_UP; - p->core_state = FS_FEEDING; - if_feed_baby(p); - rt_feed_baby(p); - p->core_state = FS_HAPPY; - add_tail(&proto_list, &p->n); + if (p->core_goal == FS_HAPPY) /* Going up */ + { + if (p->core_state == FS_HUNGRY && p->proto_state == PS_DOWN) + { + DBG("Kicking %s up\n", p->name); + proto_notify_state(p, (q->start ? q->start(p) : PS_UP)); + } + } + else /* Going down */ + { + if (p->proto_state == PS_START || p->proto_state == PS_UP) + { + DBG("Kicking %s down\n", p->name); + proto_notify_state(p, (q->shutdown ? q->shutdown(p) : PS_DOWN)); + } + } +} + +static void +proto_set_goal(struct proto *p, unsigned goal) +{ + if (p->disabled) + goal = FS_HUNGRY; + p->core_goal = goal; + proto_rethink_goal(p); } void @@ -126,32 +164,29 @@ protos_start(void) struct proto *p, *n; debug("Protocol start\n"); - WALK_LIST_DELSAFE(p, n, inactive_proto_list) - { - debug("Starting %s\n", p->cf->name); - proto_start(p); - } + WALK_LIST_DELSAFE(p, n, initial_proto_list) + proto_set_goal(p, FS_HAPPY); } void protos_dump_all(void) { struct proto *p; - static char *p_states[] = { "DOWN", "START", "UP", "STOP" }; - static char *c_states[] = { "HUNGRY", "FEEDING", "HAPPY", "FLUSHING" }; debug("Protocols:\n"); WALK_LIST(p, proto_list) { - debug(" protocol %s: state %s/%s\n", p->cf->name, p_states[p->proto_state], c_states[p->core_state]); + debug(" protocol %s: state %s/%s\n", p->name, p_states[p->proto_state], c_states[p->core_state]); if (p->disabled) debug("\tDISABLED\n"); else if (p->proto->dump) p->proto->dump(p); } WALK_LIST(p, inactive_proto_list) - debug(" inactive %s\n", p->cf->name); + debug(" inactive %s: state %s/%s\n", p->name, p_states[p->proto_state], c_states[p->core_state]); + WALK_LIST(p, initial_proto_list) + debug(" initial %s\n", p->name); } void @@ -165,4 +200,84 @@ protos_build(void) #ifdef CONFIG_STATIC add_tail(&protocol_list, &proto_static.n); #endif + proto_pool = rp_new(&root_pool, "Protocols"); +} + +static void +proto_fell_down(struct proto *p) +{ + DBG("Protocol %s down\n", p->name); + proto_rethink_goal(p); +} + +static void +proto_feed(void *P) +{ + struct proto *p = P; + + DBG("Feeding protocol %s\n", p->name); + if_feed_baby(p); + rt_feed_baby(p); + p->core_state = FS_HAPPY; + proto_relink(p); + DBG("Protocol %s up and running\n", p->name); +} + +static void +proto_flush(void *P) +{ + struct proto *p = P; + + DBG("Flushing protocol %s\n", p->name); + bug("Protocol flushing not supported yet!"); /* FIXME */ +} + +void +proto_notify_state(struct proto *p, unsigned ps) +{ + unsigned ops = p->proto_state; + unsigned cs = p->core_state; + + DBG("%s reporting state transition %s/%s -> */%s\n", p->name, c_states[cs], p_states[ops], p_states[ps]); + if (ops == ps) + return; + + switch (ps) + { + case PS_DOWN: + if (cs == FS_HUNGRY) /* Shutdown finished */ + proto_fell_down(p); + else if (cs == FS_FLUSHING) /* Still flushing... */ + ; + else /* Need to start flushing */ + goto schedule_flush; + break; + case PS_START: + ASSERT(ops == PS_DOWN); + ASSERT(cs == FS_HUNGRY); + break; + case PS_UP: + ASSERT(ops == PS_DOWN || ops == PS_START); + ASSERT(cs == FS_HUNGRY); + DBG("%s: Scheduling meal\n", p->name); + cs = FS_FEEDING; + p->attn->hook = proto_feed; + ev_schedule(p->attn); + break; + case PS_STOP: + if (cs == FS_FEEDING || cs == FS_HAPPY) + { + schedule_flush: + DBG("%s: Scheduling flush\n", p->name); + cs = FS_FLUSHING; + p->attn->hook = proto_flush; + ev_schedule(p->attn); + } + default: + error: + bug("Invalid state transition for %s from %s/%s to */%s", p->name, c_states[cs], p_states[ops], p_states[ps]); + } + p->proto_state = ps; + p->core_state = cs; + proto_relink(p); } -- cgit v1.2.3