ldpd: use red-black trees to store 'adj' elements

Using red-black trees instead of linked lists brings the following
benefits:
1 - Elements are naturally ordered (no need to reorder anything before
    outputting data to the user);
2 - Faster lookups/deletes: O(log n) time complexity against O(n).

The insert operation with red-black trees is more expensive though,
but that's not a big issue since lookups are much more frequent.

Signed-off-by: Renato Westphal <renato@opensourcerouting.org>

diff --git a/ldpd/adjacency.c b/ldpd/adjacency.c
index f01f7a12fa91cbfcf2486da22f00b5680ceb3eb5..69031bdd758b14f3b2e9d1b573e4e68bee77b234 100644 (file)
--- a/ldpd/adjacency.c
+++ b/ldpd/adjacency.c
@@ -25,6 +25,7 @@
 #include "ldpe.h"
 #include "log.h"
 
+static __inline int adj_compare(struct adj *, struct adj *);
 static int      adj_itimer(struct thread *);
 static __inline int tnbr_compare(struct tnbr *, struct tnbr *);
 static void     tnbr_del(struct ldpd_conf *, struct tnbr *);
@@ -32,8 +33,41 @@ static int    tnbr_hello_timer(struct thread *);
 static void     tnbr_start_hello_timer(struct tnbr *);
 static void     tnbr_stop_hello_timer(struct tnbr *);
 
+RB_GENERATE(global_adj_head, adj, global_entry, adj_compare)
+RB_GENERATE(nbr_adj_head, adj, nbr_entry, adj_compare)
+RB_GENERATE(ia_adj_head, adj, ia_entry, adj_compare)
 RB_GENERATE(tnbr_head, tnbr, entry, tnbr_compare)
 
+static __inline int
+adj_compare(struct adj *a, struct adj *b)
+{
+       if (a->source.type < b->source.type)
+               return (-1);
+       if (a->source.type > b->source.type)
+               return (1);
+
+       switch (a->source.type) {
+       case HELLO_LINK:
+               if (a->source.link.ia->af < b->source.link.ia->af)
+                       return (-1);
+               if (a->source.link.ia->af > b->source.link.ia->af)
+                       return (1);
+               return (ldp_addrcmp(a->source.link.ia->af,
+                   &a->source.link.src_addr, &b->source.link.src_addr));
+       case HELLO_TARGETED:
+               if (a->source.target->af < b->source.target->af)
+                       return (-1);
+               if (a->source.target->af > b->source.target->af)
+                       return (1);
+               return (ldp_addrcmp(a->source.target->af,
+                   &a->source.target->addr, &b->source.target->addr));
+       default:
+               fatalx("adj_get_af: unknown hello type");
+       }
+
+       return (0);
+}
+
 struct adj *
 adj_new(struct in_addr lsr_id, struct hello_source *source,
     union ldpd_addr *addr)
@@ -51,11 +85,11 @@ adj_new(struct in_addr lsr_id, struct hello_source *source,
        adj->source = *source;
        adj->trans_addr = *addr;
 
-       LIST_INSERT_HEAD(&global.adj_list, adj, global_entry);
+       RB_INSERT(global_adj_head, &global.adj_tree, adj);
 
        switch (source->type) {
        case HELLO_LINK:
-               LIST_INSERT_HEAD(&source->link.ia->adj_list, adj, ia_entry);
+               RB_INSERT(ia_adj_head, &source->link.ia->adj_tree, adj);
                break;
        case HELLO_TARGETED:
                source->target->adj = adj;
@@ -73,12 +107,12 @@ adj_del_single(struct adj *adj)
 
        adj_stop_itimer(adj);
 
-       LIST_REMOVE(adj, global_entry);
+       RB_REMOVE(global_adj_head, &global.adj_tree, adj);
        if (adj->nbr)
-               LIST_REMOVE(adj, nbr_entry);
+               RB_REMOVE(nbr_adj_head, &adj->nbr->adj_tree, adj);
        switch (adj->source.type) {
        case HELLO_LINK:
-               LIST_REMOVE(adj, ia_entry);
+               RB_REMOVE(ia_adj_head, &adj->source.link.ia->adj_tree, adj);
                break;
        case HELLO_TARGETED:
                adj->source.target->adj = NULL;
@@ -102,7 +136,7 @@ adj_del(struct adj *adj, uint32_t notif_status)
         * then delete it.
         */
        if (nbr && nbr_adj_count(nbr, nbr->af) == 0) {
-               LIST_FOREACH_SAFE(adj, &nbr->adj_list, nbr_entry, atmp)
+               RB_FOREACH_SAFE(adj, nbr_adj_head, &nbr->adj_tree, atmp)
                        adj_del_single(adj);
                session_shutdown(nbr, notif_status, 0, 0);
                nbr_del(nbr);
@@ -112,27 +146,9 @@ adj_del(struct adj *adj, uint32_t notif_status)
 struct adj *
 adj_find(struct hello_source *source)
 {
-       struct adj *adj;
-
-       LIST_FOREACH(adj, &global.adj_list, global_entry) {
-               if (adj->source.type != source->type)
-                       continue;
-
-               switch (source->type) {
-               case HELLO_LINK:
-                       if (ldp_addrcmp(source->link.ia->af,
-                           &adj->source.link.src_addr,
-                           &source->link.src_addr) == 0)
-                               return (adj);
-                       break;
-               case HELLO_TARGETED:
-                       if (adj->source.target == source->target)
-                               return (adj);
-                       break;
-               }
-       }
-
-       return (NULL);
+       struct adj       adj;
+       adj.source = *source;
+       return (RB_FIND(global_adj_head, &global.adj_tree, &adj));
 }
 
 int

diff --git a/ldpd/hello.c b/ldpd/hello.c
index 0833ebbafb30e4b00681ac505b98677803b791b5..95be1d51113cab047f824d69243d921c3183daac 100644 (file)
--- a/ldpd/hello.c
+++ b/ldpd/hello.c
@@ -364,7 +364,7 @@ recv_hello(struct in_addr lsr_id, struct ldp_msg *msg, int af,
                adj = adj_new(lsr_id, &source, &trans_addr);
                if (nbr) {
                        adj->nbr = nbr;
-                       LIST_INSERT_HEAD(&nbr->adj_list, adj, nbr_entry);
+                       RB_INSERT(nbr_adj_head, &nbr->adj_tree, adj);
                }
        }
 

diff --git a/ldpd/interface.c b/ldpd/interface.c
index 06d36fef72dea2ee357a84d4ccfaaefd88821db1..8fea91b878579ed9fb67b7b5c7ac2e2723dce4a1 100644 (file)
--- a/ldpd/interface.c
+++ b/ldpd/interface.c
@@ -66,14 +66,14 @@ if_new(struct kif *kif)
        iface->ipv4.iface = iface;
        iface->ipv4.enabled = 0;
        iface->ipv4.state = IF_STA_DOWN;
-       LIST_INIT(&iface->ipv4.adj_list);
+       RB_INIT(&iface->ipv4.adj_tree);
 
        /* ipv6 */
        iface->ipv6.af = AF_INET6;
        iface->ipv6.iface = iface;
        iface->ipv6.enabled = 0;
        iface->ipv6.state = IF_STA_DOWN;
-       LIST_INIT(&iface->ipv6.adj_list);
+       RB_INIT(&iface->ipv6.adj_tree);
 
        return (iface);
 }
@@ -293,7 +293,7 @@ if_reset(struct iface *iface, int af)
        ia = iface_af_get(iface, af);
        if_stop_hello_timer(ia);
 
-       while ((adj = LIST_FIRST(&ia->adj_list)) != NULL)
+       while ((adj = RB_ROOT(&ia->adj_tree)) != NULL)
                adj_del(adj, S_SHUTDOWN);
 
        /* try to cleanup */
@@ -465,7 +465,7 @@ if_to_ctl(struct iface_af *ia)
                ictl.uptime = 0;
 
        ictl.adj_cnt = 0;
-       LIST_FOREACH(adj, &ia->adj_list, ia_entry)
+       RB_FOREACH(adj, ia_adj_head, &ia->adj_tree)
                ictl.adj_cnt++;
 
        return (&ictl);

diff --git a/ldpd/lde.c b/ldpd/lde.c
index 78551e4d35c50d7a111d71b0879bb40627cd33bf..b19418585e979463ae2affac955c2c3f4c63f48b 100644 (file)
--- a/ldpd/lde.c
+++ b/ldpd/lde.c
@@ -483,8 +483,8 @@ lde_dispatch_parent(struct thread *thread)
                        memcpy(niface, imsg.data, sizeof(struct iface));
 
                        LIST_INIT(&niface->addr_list);
-                       LIST_INIT(&niface->ipv4.adj_list);
-                       LIST_INIT(&niface->ipv6.adj_list);
+                       RB_INIT(&niface->ipv4.adj_tree);
+                       RB_INIT(&niface->ipv6.adj_tree);
                        niface->ipv4.iface = niface;
                        niface->ipv6.iface = niface;
 

diff --git a/ldpd/ldpd.h b/ldpd/ldpd.h
index 79af31d8051d05a3e6d2e9875001adf18734c991..bfce014b9b1079d49967d29743f7270705aaccc4 100644 (file)
--- a/ldpd/ldpd.h
+++ b/ldpd/ldpd.h
@@ -196,7 +196,10 @@ enum nbr_action {
        NBR_ACT_CLOSE_SESSION
 };
 
-TAILQ_HEAD(mapping_head, mapping_entry);
+/* forward declarations */
+RB_HEAD(global_adj_head, adj);
+RB_HEAD(nbr_adj_head, adj);
+RB_HEAD(ia_adj_head, adj);
 
 struct map {
        uint8_t         type;
@@ -256,7 +259,7 @@ struct iface_af {
        int                      af;
        int                      enabled;
        int                      state;
-       LIST_HEAD(, adj)         adj_list;
+       struct ia_adj_head       adj_tree;
        time_t                   uptime;
        struct thread           *hello_timer;
        uint16_t                 hello_holdtime;
@@ -450,7 +453,7 @@ struct ldpd_global {
        uint32_t                 conf_seqnum;
        int                      pfkeysock;
        struct if_addr_head      addr_list;
-       LIST_HEAD(, adj)         adj_list;
+       struct global_adj_head   adj_tree;
        struct in_addr           mcast_addr_v4;
        struct in6_addr          mcast_addr_v6;
        TAILQ_HEAD(, pending_conn) pending_conns;

diff --git a/ldpd/ldpe.c b/ldpd/ldpe.c
index 9a03410069f5436e641ee1a68eab604fba638068..798085b935711c99a53edb47941865a2d577bd8e 100644 (file)
--- a/ldpd/ldpe.c
+++ b/ldpd/ldpe.c
@@ -111,7 +111,7 @@ ldpe(const char *user, const char *group, const char *ctl_path)
        ldpd_process = PROC_LDP_ENGINE;
 
        LIST_INIT(&global.addr_list);
-       LIST_INIT(&global.adj_list);
+       RB_INIT(&global.adj_tree);
        TAILQ_INIT(&global.pending_conns);
        if (inet_pton(AF_INET, AllRouters_v4, &global.mcast_addr_v4) != 1)
                fatal("inet_pton");
@@ -210,7 +210,7 @@ ldpe_shutdown(void)
                LIST_REMOVE(if_addr, entry);
                free(if_addr);
        }
-       while ((adj = LIST_FIRST(&global.adj_list)) != NULL)
+       while ((adj = RB_ROOT(&global.adj_tree)) != NULL)
                adj_del(adj, S_SHUTDOWN);
 
        /* clean up */
@@ -426,8 +426,8 @@ ldpe_dispatch_main(struct thread *thread)
                        memcpy(niface, imsg.data, sizeof(struct iface));
 
                        LIST_INIT(&niface->addr_list);
-                       LIST_INIT(&niface->ipv4.adj_list);
-                       LIST_INIT(&niface->ipv6.adj_list);
+                       RB_INIT(&niface->ipv4.adj_tree);
+                       RB_INIT(&niface->ipv6.adj_tree);
                        niface->ipv4.iface = niface;
                        niface->ipv6.iface = niface;
 
@@ -815,18 +815,18 @@ ldpe_adj_ctl(struct ctl_conn *c)
                        continue;
 
                strlcpy(ictl.name, iface->name, sizeof(ictl.name));
-               if (LIST_EMPTY(&iface->ipv4.adj_list) &&
-                   LIST_EMPTY(&iface->ipv6.adj_list))
+               if (RB_EMPTY(&iface->ipv4.adj_tree) &&
+                   RB_EMPTY(&iface->ipv6.adj_tree))
                        ictl.no_adj = 1;
                imsg_compose_event(&c->iev, IMSG_CTL_SHOW_DISC_IFACE, 0, 0,
                    -1, &ictl, sizeof(ictl));
 
-               LIST_FOREACH(adj, &iface->ipv4.adj_list, ia_entry) {
+               RB_FOREACH(adj, ia_adj_head, &iface->ipv4.adj_tree) {
                        actl = adj_to_ctl(adj);
                        imsg_compose_event(&c->iev, IMSG_CTL_SHOW_DISC_ADJ,
                            0, 0, -1, actl, sizeof(struct ctl_adj));
                }
-               LIST_FOREACH(adj, &iface->ipv6.adj_list, ia_entry) {
+               RB_FOREACH(adj, ia_adj_head, &iface->ipv6.adj_tree) {
                        actl = adj_to_ctl(adj);
                        imsg_compose_event(&c->iev, IMSG_CTL_SHOW_DISC_ADJ,
                            0, 0, -1, actl, sizeof(struct ctl_adj));
@@ -870,7 +870,7 @@ ldpe_nbr_ctl(struct ctl_conn *c)
                imsg_compose_event(&c->iev, IMSG_CTL_SHOW_NBR, 0, 0, -1, nctl,
                    sizeof(struct ctl_nbr));
 
-               LIST_FOREACH(adj, &nbr->adj_list, nbr_entry) {
+               RB_FOREACH(adj, nbr_adj_head, &nbr->adj_tree) {
                        actl = adj_to_ctl(adj);
                        imsg_compose_event(&c->iev, IMSG_CTL_SHOW_NBR_DISC,
                            0, 0, -1, actl, sizeof(struct ctl_adj));

diff --git a/ldpd/ldpe.h b/ldpd/ldpe.h
index a57727591a8edc67ac6f63e2c5009454656ed376..6a2f4b3cf5b3af6bcb4f995d7cebbb3ff423e18e 100644 (file)
--- a/ldpd/ldpe.h
+++ b/ldpd/ldpe.h
@@ -32,6 +32,9 @@
 #define min(x,y) ((x) <= (y) ? (x) : (y))
 #define max(x,y) ((x) > (y) ? (x) : (y))
 
+/* forward declarations */
+TAILQ_HEAD(mapping_head, mapping_entry);
+
 struct hello_source {
        enum hello_type          type;
        struct {
@@ -42,9 +45,7 @@ struct hello_source {
 };
 
 struct adj {
-       LIST_ENTRY(adj)          global_entry;
-       LIST_ENTRY(adj)          nbr_entry;
-       LIST_ENTRY(adj)          ia_entry;
+       RB_ENTRY(adj)            global_entry, nbr_entry, ia_entry;
        struct in_addr           lsr_id;
        struct nbr              *nbr;
        int                      ds_tlv;
@@ -53,6 +54,9 @@ struct adj {
        uint16_t                 holdtime;
        union ldpd_addr          trans_addr;
 };
+RB_PROTOTYPE(global_adj_head, adj, global_entry, adj_compare)
+RB_PROTOTYPE(nbr_adj_head, adj, nbr_entry, adj_compare)
+RB_PROTOTYPE(ia_adj_head, adj, ia_entry, adj_compare)
 
 struct tcp_conn {
        struct nbr              *nbr;
@@ -67,7 +71,7 @@ struct tcp_conn {
 struct nbr {
        RB_ENTRY(nbr)            id_tree, addr_tree, pid_tree;
        struct tcp_conn         *tcp;
-       LIST_HEAD(, adj)         adj_list;      /* adjacencies */
+       struct nbr_adj_head      adj_tree;      /* adjacencies */
        struct thread           *ev_connect;
        struct thread           *keepalive_timer;
        struct thread           *keepalive_timeout;

diff --git a/ldpd/neighbor.c b/ldpd/neighbor.c
index 5addc4dda27ae150c0c21fa2fe810c5636dbac85..d24ceb1229dcee6519b932c7127a7ba6e97646c4 100644 (file)
--- a/ldpd/neighbor.c
+++ b/ldpd/neighbor.c
@@ -229,7 +229,7 @@ nbr_new(struct in_addr id, int af, int ds_tlv, union ldpd_addr *addr,
        if ((nbr = calloc(1, sizeof(*nbr))) == NULL)
                fatal(__func__);
 
-       LIST_INIT(&nbr->adj_list);
+       RB_INIT(&nbr->adj_tree);
        nbr->state = NBR_STA_PRESENT;
        nbr->peerid = 0;
        nbr->af = af;
@@ -244,10 +244,10 @@ nbr_new(struct in_addr id, int af, int ds_tlv, union ldpd_addr *addr,
        nbr->raddr_scope = scope_id;
        nbr->conf_seqnum = 0;
 
-       LIST_FOREACH(adj, &global.adj_list, global_entry) {
+       RB_FOREACH(adj, global_adj_head, &global.adj_tree) {
                if (adj->lsr_id.s_addr == nbr->id.s_addr) {
                        adj->nbr = nbr;
-                       LIST_INSERT_HEAD(&nbr->adj_list, adj, nbr_entry);
+                       RB_INSERT(nbr_adj_head, &nbr->adj_tree, adj);
                }
        }
 
@@ -366,7 +366,7 @@ nbr_adj_count(struct nbr *nbr, int af)
        struct adj      *adj;
        int              total = 0;
 
-       LIST_FOREACH(adj, &nbr->adj_list, nbr_entry)
+       RB_FOREACH(adj, nbr_adj_head, &nbr->adj_tree)
                if (adj_get_af(adj) == af)
                        total++;
 
@@ -624,7 +624,7 @@ nbr_establish_connection(struct nbr *nbr)
         * Send an extra hello to guarantee that the remote peer has formed
         * an adjacency as well.
         */
-       LIST_FOREACH(adj, &nbr->adj_list, nbr_entry)
+       RB_FOREACH(adj, nbr_adj_head, &nbr->adj_tree)
                send_hello(adj->source.type, adj->source.link.ia,
                    adj->source.target);