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Diffstat (limited to 'net')
-rw-r--r--net/tipc/name_table.c279
1 files changed, 179 insertions, 100 deletions
diff --git a/net/tipc/name_table.c b/net/tipc/name_table.c
index 92d04dc2a44b..359b2bc888cf 100644
--- a/net/tipc/name_table.c
+++ b/net/tipc/name_table.c
@@ -36,6 +36,7 @@
#include <net/sock.h>
#include <linux/list_sort.h>
+#include <linux/rbtree_augmented.h>
#include "core.h"
#include "netlink.h"
#include "name_table.h"
@@ -51,6 +52,7 @@
* @lower: service range lower bound
* @upper: service range upper bound
* @tree_node: member of service range RB tree
+ * @max: largest 'upper' in this node subtree
* @local_publ: list of identical publications made from this node
* Used by closest_first lookup and multicast lookup algorithm
* @all_publ: all publications identical to this one, whatever node and scope
@@ -60,6 +62,7 @@ struct service_range {
u32 lower;
u32 upper;
struct rb_node tree_node;
+ u32 max;
struct list_head local_publ;
struct list_head all_publ;
};
@@ -84,6 +87,130 @@ struct tipc_service {
struct rcu_head rcu;
};
+#define service_range_upper(sr) ((sr)->upper)
+RB_DECLARE_CALLBACKS_MAX(static, sr_callbacks,
+ struct service_range, tree_node, u32, max,
+ service_range_upper)
+
+#define service_range_entry(rbtree_node) \
+ (container_of(rbtree_node, struct service_range, tree_node))
+
+#define service_range_overlap(sr, start, end) \
+ ((sr)->lower <= (end) && (sr)->upper >= (start))
+
+/**
+ * service_range_foreach_match - iterate over tipc service rbtree for each
+ * range match
+ * @sr: the service range pointer as a loop cursor
+ * @sc: the pointer to tipc service which holds the service range rbtree
+ * @start, end: the range (end >= start) for matching
+ */
+#define service_range_foreach_match(sr, sc, start, end) \
+ for (sr = service_range_match_first((sc)->ranges.rb_node, \
+ start, \
+ end); \
+ sr; \
+ sr = service_range_match_next(&(sr)->tree_node, \
+ start, \
+ end))
+
+/**
+ * service_range_match_first - find first service range matching a range
+ * @n: the root node of service range rbtree for searching
+ * @start, end: the range (end >= start) for matching
+ *
+ * Return: the leftmost service range node in the rbtree that overlaps the
+ * specific range if any. Otherwise, returns NULL.
+ */
+static struct service_range *service_range_match_first(struct rb_node *n,
+ u32 start, u32 end)
+{
+ struct service_range *sr;
+ struct rb_node *l, *r;
+
+ /* Non overlaps in tree at all? */
+ if (!n || service_range_entry(n)->max < start)
+ return NULL;
+
+ while (n) {
+ l = n->rb_left;
+ if (l && service_range_entry(l)->max >= start) {
+ /* A leftmost overlap range node must be one in the left
+ * subtree. If not, it has lower > end, then nodes on
+ * the right side cannot satisfy the condition either.
+ */
+ n = l;
+ continue;
+ }
+
+ /* No one in the left subtree can match, return if this node is
+ * an overlap i.e. leftmost.
+ */
+ sr = service_range_entry(n);
+ if (service_range_overlap(sr, start, end))
+ return sr;
+
+ /* Ok, try to lookup on the right side */
+ r = n->rb_right;
+ if (sr->lower <= end &&
+ r && service_range_entry(r)->max >= start) {
+ n = r;
+ continue;
+ }
+ break;
+ }
+
+ return NULL;
+}
+
+/**
+ * service_range_match_next - find next service range matching a range
+ * @n: a node in service range rbtree from which the searching starts
+ * @start, end: the range (end >= start) for matching
+ *
+ * Return: the next service range node to the given node in the rbtree that
+ * overlaps the specific range if any. Otherwise, returns NULL.
+ */
+static struct service_range *service_range_match_next(struct rb_node *n,
+ u32 start, u32 end)
+{
+ struct service_range *sr;
+ struct rb_node *p, *r;
+
+ while (n) {
+ r = n->rb_right;
+ if (r && service_range_entry(r)->max >= start)
+ /* A next overlap range node must be one in the right
+ * subtree. If not, it has lower > end, then any next
+ * successor (- an ancestor) of this node cannot
+ * satisfy the condition either.
+ */
+ return service_range_match_first(r, start, end);
+
+ /* No one in the right subtree can match, go up to find an
+ * ancestor of this node which is parent of a left-hand child.
+ */
+ while ((p = rb_parent(n)) && n == p->rb_right)
+ n = p;
+ if (!p)
+ break;
+
+ /* Return if this ancestor is an overlap */
+ sr = service_range_entry(p);
+ if (service_range_overlap(sr, start, end))
+ return sr;
+
+ /* Ok, try to lookup more from this ancestor */
+ if (sr->lower <= end) {
+ n = p;
+ continue;
+ }
+ break;
+ }
+
+ return NULL;
+}
+
static int hash(int x)
{
return x & (TIPC_NAMETBL_SIZE - 1);
@@ -139,84 +266,51 @@ static struct tipc_service *tipc_service_create(u32 type, struct hlist_head *hd)
return service;
}
-/**
- * tipc_service_first_range - find first service range in tree matching instance
- *
- * Very time-critical, so binary search through range rb tree
- */
-static struct service_range *tipc_service_first_range(struct tipc_service *sc,
- u32 instance)
-{
- struct rb_node *n = sc->ranges.rb_node;
- struct service_range *sr;
-
- while (n) {
- sr = container_of(n, struct service_range, tree_node);
- if (sr->lower > instance)
- n = n->rb_left;
- else if (sr->upper < instance)
- n = n->rb_right;
- else
- return sr;
- }
- return NULL;
-}
-
/* tipc_service_find_range - find service range matching publication parameters
*/
static struct service_range *tipc_service_find_range(struct tipc_service *sc,
u32 lower, u32 upper)
{
- struct rb_node *n = sc->ranges.rb_node;
struct service_range *sr;
- sr = tipc_service_first_range(sc, lower);
- if (!sr)
- return NULL;
-
- /* Look for exact match */
- for (n = &sr->tree_node; n; n = rb_next(n)) {
- sr = container_of(n, struct service_range, tree_node);
- if (sr->upper == upper)
- break;
+ service_range_foreach_match(sr, sc, lower, upper) {
+ /* Look for exact match */
+ if (sr->lower == lower && sr->upper == upper)
+ return sr;
}
- if (!n || sr->lower != lower || sr->upper != upper)
- return NULL;
- return sr;
+ return NULL;
}
static struct service_range *tipc_service_create_range(struct tipc_service *sc,
u32 lower, u32 upper)
{
struct rb_node **n, *parent = NULL;
- struct service_range *sr, *tmp;
+ struct service_range *sr;
n = &sc->ranges.rb_node;
while (*n) {
- tmp = container_of(*n, struct service_range, tree_node);
parent = *n;
- tmp = container_of(parent, struct service_range, tree_node);
- if (lower < tmp->lower)
- n = &(*n)->rb_left;
- else if (lower > tmp->lower)
- n = &(*n)->rb_right;
- else if (upper < tmp->upper)
- n = &(*n)->rb_left;
- else if (upper > tmp->upper)
- n = &(*n)->rb_right;
+ sr = service_range_entry(parent);
+ if (lower == sr->lower && upper == sr->upper)
+ return sr;
+ if (sr->max < upper)
+ sr->max = upper;
+ if (lower <= sr->lower)
+ n = &parent->rb_left;
else
- return tmp;
+ n = &parent->rb_right;
}
sr = kzalloc(sizeof(*sr), GFP_ATOMIC);
if (!sr)
return NULL;
sr->lower = lower;
sr->upper = upper;
+ sr->max = upper;
INIT_LIST_HEAD(&sr->local_publ);
INIT_LIST_HEAD(&sr->all_publ);
rb_link_node(&sr->tree_node, parent, n);
- rb_insert_color(&sr->tree_node, &sc->ranges);
+ rb_insert_augmented(&sr->tree_node, &sc->ranges, &sr_callbacks);
return sr;
}
@@ -310,7 +404,6 @@ static void tipc_service_subscribe(struct tipc_service *service,
struct list_head publ_list;
struct service_range *sr;
struct tipc_name_seq ns;
- struct rb_node *n;
u32 filter;
ns.type = tipc_sub_read(sb, seq.type);
@@ -325,13 +418,7 @@ static void tipc_service_subscribe(struct tipc_service *service,
return;
INIT_LIST_HEAD(&publ_list);
- for (n = rb_first(&service->ranges); n; n = rb_next(n)) {
- sr = container_of(n, struct service_range, tree_node);
- if (sr->lower > ns.upper)
- break;
- if (!tipc_sub_check_overlap(&ns, sr->lower, sr->upper))
- continue;
-
+ service_range_foreach_match(sr, service, ns.lower, ns.upper) {
first = NULL;
list_for_each_entry(p, &sr->all_publ, all_publ) {
if (filter & TIPC_SUB_PORTS)
@@ -425,7 +512,7 @@ struct publication *tipc_nametbl_remove_publ(struct net *net, u32 type,
/* Remove service range item if this was its last publication */
if (list_empty(&sr->all_publ)) {
- rb_erase(&sr->tree_node, &sc->ranges);
+ rb_erase_augmented(&sr->tree_node, &sc->ranges, &sr_callbacks);
kfree(sr);
}
@@ -473,34 +560,39 @@ u32 tipc_nametbl_translate(struct net *net, u32 type, u32 instance, u32 *dnode)
rcu_read_lock();
sc = tipc_service_find(net, type);
if (unlikely(!sc))
- goto not_found;
+ goto exit;
spin_lock_bh(&sc->lock);
- sr = tipc_service_first_range(sc, instance);
- if (unlikely(!sr))
- goto no_match;
-
- /* Select lookup algorithm: local, closest-first or round-robin */
- if (*dnode == self) {
- list = &sr->local_publ;
- if (list_empty(list))
- goto no_match;
- p = list_first_entry(list, struct publication, local_publ);
- list_move_tail(&p->local_publ, &sr->local_publ);
- } else if (legacy && !*dnode && !list_empty(&sr->local_publ)) {
- list = &sr->local_publ;
- p = list_first_entry(list, struct publication, local_publ);
- list_move_tail(&p->local_publ, &sr->local_publ);
- } else {
- list = &sr->all_publ;
- p = list_first_entry(list, struct publication, all_publ);
- list_move_tail(&p->all_publ, &sr->all_publ);
+ service_range_foreach_match(sr, sc, instance, instance) {
+ /* Select lookup algo: local, closest-first or round-robin */
+ if (*dnode == self) {
+ list = &sr->local_publ;
+ if (list_empty(list))
+ continue;
+ p = list_first_entry(list, struct publication,
+ local_publ);
+ list_move_tail(&p->local_publ, &sr->local_publ);
+ } else if (legacy && !*dnode && !list_empty(&sr->local_publ)) {
+ list = &sr->local_publ;
+ p = list_first_entry(list, struct publication,
+ local_publ);
+ list_move_tail(&p->local_publ, &sr->local_publ);
+ } else {
+ list = &sr->all_publ;
+ p = list_first_entry(list, struct publication,
+ all_publ);
+ list_move_tail(&p->all_publ, &sr->all_publ);
+ }
+ port = p->port;
+ node = p->node;
+ /* Todo: as for legacy, pick the first matching range only, a
+ * "true" round-robin will be performed as needed.
+ */
+ break;
}
- port = p->port;
- node = p->node;
-no_match:
spin_unlock_bh(&sc->lock);
-not_found:
+
+exit:
rcu_read_unlock();
*dnode = node;
return port;
@@ -523,7 +615,8 @@ bool tipc_nametbl_lookup(struct net *net, u32 type, u32 instance, u32 scope,
spin_lock_bh(&sc->lock);
- sr = tipc_service_first_range(sc, instance);
+ /* Todo: a full search i.e. service_range_foreach_match() instead? */
+ sr = service_range_match_first(sc->ranges.rb_node, instance, instance);
if (!sr)
goto no_match;
@@ -552,7 +645,6 @@ void tipc_nametbl_mc_lookup(struct net *net, u32 type, u32 lower, u32 upper,
struct service_range *sr;
struct tipc_service *sc;
struct publication *p;
- struct rb_node *n;
rcu_read_lock();
sc = tipc_service_find(net, type);
@@ -560,13 +652,7 @@ void tipc_nametbl_mc_lookup(struct net *net, u32 type, u32 lower, u32 upper,
goto exit;
spin_lock_bh(&sc->lock);
-
- for (n = rb_first(&sc->ranges); n; n = rb_next(n)) {
- sr = container_of(n, struct service_range, tree_node);
- if (sr->upper < lower)
- continue;
- if (sr->lower > upper)
- break;
+ service_range_foreach_match(sr, sc, lower, upper) {
list_for_each_entry(p, &sr->local_publ, local_publ) {
if (p->scope == scope || (!exact && p->scope < scope))
tipc_dest_push(dports, 0, p->port);
@@ -587,7 +673,6 @@ void tipc_nametbl_lookup_dst_nodes(struct net *net, u32 type, u32 lower,
struct service_range *sr;
struct tipc_service *sc;
struct publication *p;
- struct rb_node *n;
rcu_read_lock();
sc = tipc_service_find(net, type);
@@ -595,13 +680,7 @@ void tipc_nametbl_lookup_dst_nodes(struct net *net, u32 type, u32 lower,
goto exit;
spin_lock_bh(&sc->lock);
-
- for (n = rb_first(&sc->ranges); n; n = rb_next(n)) {
- sr = container_of(n, struct service_range, tree_node);
- if (sr->upper < lower)
- continue;
- if (sr->lower > upper)
- break;
+ service_range_foreach_match(sr, sc, lower, upper) {
list_for_each_entry(p, &sr->all_publ, all_publ) {
tipc_nlist_add(nodes, p->node);
}
@@ -799,7 +878,7 @@ static void tipc_service_delete(struct net *net, struct tipc_service *sc)
tipc_service_remove_publ(sr, p->node, p->key);
kfree_rcu(p, rcu);
}
- rb_erase(&sr->tree_node, &sc->ranges);
+ rb_erase_augmented(&sr->tree_node, &sc->ranges, &sr_callbacks);
kfree(sr);
}
hlist_del_init_rcu(&sc->service_list);