ldpd: use red-black trees to store 'lde_map' 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/l2vpn.c b/ldpd/l2vpn.c
index 851ff77b7317f435f36ecbdc81054256d796ea98..c0f65868547b169b2801a90deea985ca2e65a1c9 100644 (file)
--- a/ldpd/l2vpn.c
+++ b/ldpd/l2vpn.c
@@ -459,7 +459,7 @@ l2vpn_binding_ctl(pid_t pid)
 
                fn = (struct fec_node *)f;
                if (fn->local_label == NO_LABEL &&
-                   LIST_EMPTY(&fn->downstream))
+                   RB_EMPTY(&fn->downstream))
                        continue;
 
                memset(&pwctl, 0, sizeof(pwctl));
@@ -477,7 +477,7 @@ l2vpn_binding_ctl(pid_t pid)
                } else
                        pwctl.local_label = NO_LABEL;
 
-               LIST_FOREACH(me, &fn->downstream, entry)
+               RB_FOREACH(me, lde_map_head, &fn->downstream)
                        if (f->u.pwid.lsr_id.s_addr == me->nexthop->id.s_addr)
                                break;
 

diff --git a/ldpd/lde.c b/ldpd/lde.c
index 67ed982ec515b02bf6b272925496796301858e85..a1309c64484cbd964d2c1a4d4b2a69f104b61f08 100644 (file)
--- a/ldpd/lde.c
+++ b/ldpd/lde.c
@@ -45,12 +45,14 @@ static struct lde_nbr       *lde_nbr_find(uint32_t);
 static void             lde_nbr_clear(void);
 static void             lde_nbr_addr_update(struct lde_nbr *,
                            struct lde_addr *, int);
+static __inline int     lde_map_compare(struct lde_map *, struct lde_map *);
 static void             lde_map_free(void *);
 static int              lde_address_add(struct lde_nbr *, struct lde_addr *);
 static int              lde_address_del(struct lde_nbr *, struct lde_addr *);
 static void             lde_address_list_free(struct lde_nbr *);
 
 RB_GENERATE(nbr_tree, lde_nbr, entry, lde_nbr_compare)
+RB_GENERATE(lde_map_head, lde_map, entry, lde_map_compare)
 
 struct ldpd_conf       *ldeconf;
 struct nbr_tree                 lde_nbrs = RB_INITIALIZER(&lde_nbrs);
@@ -1141,6 +1143,13 @@ lde_nbr_addr_update(struct lde_nbr *ln, struct lde_addr *lde_addr, int removed)
        }
 }
 
+static __inline int
+lde_map_compare(struct lde_map *a, struct lde_map *b)
+{
+       return (ldp_addrcmp(AF_INET, (union ldpd_addr *)&a->nexthop->id,
+           (union ldpd_addr *)&b->nexthop->id));
+}
+
 struct lde_map *
 lde_map_add(struct lde_nbr *ln, struct fec_node *fn, int sent)
 {
@@ -1154,13 +1163,15 @@ lde_map_add(struct lde_nbr *ln, struct fec_node *fn, int sent)
        me->nexthop = ln;
 
        if (sent) {
-               LIST_INSERT_HEAD(&fn->upstream, me, entry);
+               RB_INSERT(lde_map_head, &fn->upstream, me);
+               me->head = &fn->upstream;
                if (fec_insert(&ln->sent_map, &me->fec))
                        log_warnx("failed to add %s to sent map",
                            log_fec(&me->fec));
                        /* XXX on failure more cleanup is needed */
        } else {
-               LIST_INSERT_HEAD(&fn->downstream, me, entry);
+               RB_INSERT(lde_map_head, &fn->downstream, me);
+               me->head = &fn->downstream;
                if (fec_insert(&ln->recv_map, &me->fec))
                        log_warnx("failed to add %s to recv map",
                            log_fec(&me->fec));
@@ -1185,7 +1196,7 @@ lde_map_free(void *ptr)
 {
        struct lde_map  *map = ptr;
 
-       LIST_REMOVE(map, entry);
+       RB_REMOVE(lde_map_head, map->head, map);
        free(map);
 }
 

diff --git a/ldpd/lde.h b/ldpd/lde.h
index 5f5d37defb3118b3209037d01dc32309b3edef2d..fe90b2c8524bae34cd77d80a2ae73cb593c842bb 100644 (file)
--- a/ldpd/lde.h
+++ b/ldpd/lde.h
@@ -62,10 +62,13 @@ struct lde_req {
 /* mapping entries */
 struct lde_map {
        struct fec               fec;
-       LIST_ENTRY(lde_map)      entry;
+       struct lde_map_head     *head;  /* fec_node's upstream/downstream */
+       RB_ENTRY(lde_map)        entry;
        struct lde_nbr          *nexthop;
        struct map               map;
 };
+RB_HEAD(lde_map_head, lde_map);
+RB_PROTOTYPE(lde_map_head, lde_map, entry, lde_map_cmp);
 
 /* withdraw entries */
 struct lde_wdraw {
@@ -112,8 +115,8 @@ struct fec_node {
        struct fec               fec;
 
        LIST_HEAD(, fec_nh)      nexthops;      /* fib nexthops */
-       LIST_HEAD(, lde_map)     downstream;    /* recv mappings */
-       LIST_HEAD(, lde_map)     upstream;      /* sent mappings */
+       struct lde_map_head      downstream;    /* recv mappings */
+       struct lde_map_head      upstream;      /* sent mappings */
 
        uint32_t                 local_label;
        void                    *data;          /* fec specific data */

diff --git a/ldpd/lde_lib.c b/ldpd/lde_lib.c
index 14ac592af96221874a4f7343f4b6fcd33313bfde..df65edad1a3d5b8d1c84c816363961752e9bdbde 100644 (file)
--- a/ldpd/lde_lib.c
+++ b/ldpd/lde_lib.c
@@ -159,7 +159,7 @@ rt_dump(pid_t pid)
        RB_FOREACH(f, fec_tree, &ft) {
                fn = (struct fec_node *)f;
                if (fn->local_label == NO_LABEL &&
-                   LIST_EMPTY(&fn->downstream))
+                   RB_EMPTY(&fn->downstream))
                        continue;
 
                rtctl.first = 1;
@@ -179,7 +179,7 @@ rt_dump(pid_t pid)
                }
 
                rtctl.local_label = fn->local_label;
-               LIST_FOREACH(me, &fn->downstream, entry) {
+               RB_FOREACH(me, lde_map_head, &fn->downstream) {
                        rtctl.in_use = lde_nbr_is_nexthop(fn, me->nexthop);
                        rtctl.nexthop = me->nexthop->id;
                        rtctl.remote_label = me->map.label;
@@ -188,7 +188,7 @@ rt_dump(pid_t pid)
                            &rtctl, sizeof(rtctl));
                        rtctl.first = 0;
                }
-               if (LIST_EMPTY(&fn->downstream)) {
+               if (RB_EMPTY(&fn->downstream)) {
                        rtctl.in_use = 0;
                        rtctl.nexthop.s_addr = INADDR_ANY;
                        rtctl.remote_label = NO_LABEL;
@@ -224,10 +224,10 @@ fec_free(void *arg)
 
        while ((fnh = LIST_FIRST(&fn->nexthops)))
                fec_nh_del(fnh);
-       if (!LIST_EMPTY(&fn->downstream))
+       if (!RB_EMPTY(&fn->downstream))
                log_warnx("%s: fec %s downstream list not empty", __func__,
                    log_fec(&fn->fec));
-       if (!LIST_EMPTY(&fn->upstream))
+       if (!RB_EMPTY(&fn->upstream))
                log_warnx("%s: fec %s upstream list not empty", __func__,
                    log_fec(&fn->fec));
 
@@ -251,8 +251,8 @@ fec_add(struct fec *fec)
 
        fn->fec = *fec;
        fn->local_label = NO_LABEL;
-       LIST_INIT(&fn->upstream);
-       LIST_INIT(&fn->downstream);
+       RB_INIT(&fn->upstream);
+       RB_INIT(&fn->downstream);
        LIST_INIT(&fn->nexthops);
 
        if (fec_insert(&ft, &fn->fec))
@@ -774,8 +774,8 @@ lde_gc_timer(struct thread *thread)
                fn = (struct fec_node *) fec;
 
                if (!LIST_EMPTY(&fn->nexthops) ||
-                   !LIST_EMPTY(&fn->downstream) ||
-                   !LIST_EMPTY(&fn->upstream))
+                   !RB_EMPTY(&fn->downstream) ||
+                   !RB_EMPTY(&fn->upstream))
                        continue;
 
                fec_remove(&ft, &fn->fec);