[IPV4]: Convert FIB Trie to RCU.
* Removes RW-lock
* Proteced read functions uses
rcu_dereference proteced with rcu_read_lock()
* writing of procted pointer w. rcu_assigen_pointer
* Insert/Replace atomic list_replace_rcu
* A BUG_ON condition removed.in trie_rebalance
With help from Paul E. McKenney.
Signed-off-by: Robert Olsson <Robert.Olsson@data.slu.se>
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/fib_trie.c b/net/ipv4/fib_trie.c
index 9c4c7f0..ff21748 100644
--- a/net/ipv4/fib_trie.c
+++ b/net/ipv4/fib_trie.c
@@ -43,7 +43,7 @@
* 2 of the License, or (at your option) any later version.
*/
-#define VERSION "0.325"
+#define VERSION "0.402"
#include <linux/config.h>
#include <asm/uaccess.h>
@@ -62,6 +62,7 @@
#include <linux/netdevice.h>
#include <linux/if_arp.h>
#include <linux/proc_fs.h>
+#include <linux/rcupdate.h>
#include <linux/skbuff.h>
#include <linux/netlink.h>
#include <linux/init.h>
@@ -81,22 +82,19 @@
#define MASK_PFX(k, l) (((l)==0)?0:(k >> (KEYLENGTH-l)) << (KEYLENGTH-l))
#define TKEY_GET_MASK(offset, bits) (((bits)==0)?0:((t_key)(-1) << (KEYLENGTH - bits) >> offset))
-static DEFINE_RWLOCK(fib_lock);
-
typedef unsigned int t_key;
#define T_TNODE 0
#define T_LEAF 1
#define NODE_TYPE_MASK 0x1UL
#define NODE_PARENT(node) \
- ((struct tnode *)((node)->parent & ~NODE_TYPE_MASK))
-#define NODE_SET_PARENT(node, ptr) \
- ((node)->parent = (((unsigned long)(ptr)) | \
- ((node)->parent & NODE_TYPE_MASK)))
-#define NODE_INIT_PARENT(node, type) \
- ((node)->parent = (type))
-#define NODE_TYPE(node) \
- ((node)->parent & NODE_TYPE_MASK)
+ ((struct tnode *)rcu_dereference(((node)->parent & ~NODE_TYPE_MASK)))
+
+#define NODE_TYPE(node) ((node)->parent & NODE_TYPE_MASK)
+
+#define NODE_SET_PARENT(node, ptr) \
+ rcu_assign_pointer((node)->parent, \
+ ((unsigned long)(ptr)) | NODE_TYPE(node))
#define IS_TNODE(n) (!(n->parent & T_LEAF))
#define IS_LEAF(n) (n->parent & T_LEAF)
@@ -110,10 +108,12 @@
t_key key;
unsigned long parent;
struct hlist_head list;
+ struct rcu_head rcu;
};
struct leaf_info {
struct hlist_node hlist;
+ struct rcu_head rcu;
int plen;
struct list_head falh;
};
@@ -125,6 +125,7 @@
unsigned short bits:5; /* 2log(KEYLENGTH) bits needed */
unsigned short full_children; /* KEYLENGTH bits needed */
unsigned short empty_children; /* KEYLENGTH bits needed */
+ struct rcu_head rcu;
struct node *child[0];
};
@@ -168,11 +169,14 @@
static kmem_cache_t *fn_alias_kmem;
static struct trie *trie_local = NULL, *trie_main = NULL;
+
+/* rcu_read_lock needs to be hold by caller from readside */
+
static inline struct node *tnode_get_child(struct tnode *tn, int i)
{
BUG_ON(i >= 1 << tn->bits);
- return tn->child[i];
+ return rcu_dereference(tn->child[i]);
}
static inline int tnode_child_length(const struct tnode *tn)
@@ -213,14 +217,6 @@
return i;
}
-/* Candidate for fib_semantics */
-
-static void fn_free_alias(struct fib_alias *fa)
-{
- fib_release_info(fa->fa_info);
- kmem_cache_free(fn_alias_kmem, fa);
-}
-
/*
To understand this stuff, an understanding of keys and all their bits is
necessary. Every node in the trie has a key associated with it, but not
@@ -292,11 +288,74 @@
static int halve_threshold = 25;
static int inflate_threshold = 50;
+
+static void __alias_free_mem(struct rcu_head *head)
+{
+ struct fib_alias *fa = container_of(head, struct fib_alias, rcu);
+ kmem_cache_free(fn_alias_kmem, fa);
+}
+
+static inline void alias_free_mem_rcu(struct fib_alias *fa)
+{
+ call_rcu(&fa->rcu, __alias_free_mem);
+}
+
+static void __leaf_free_rcu(struct rcu_head *head)
+{
+ kfree(container_of(head, struct leaf, rcu));
+}
+
+static inline void free_leaf(struct leaf *leaf)
+{
+ call_rcu(&leaf->rcu, __leaf_free_rcu);
+}
+
+static void __leaf_info_free_rcu(struct rcu_head *head)
+{
+ kfree(container_of(head, struct leaf_info, rcu));
+}
+
+static inline void free_leaf_info(struct leaf_info *leaf)
+{
+ call_rcu(&leaf->rcu, __leaf_info_free_rcu);
+}
+
+static struct tnode *tnode_alloc(unsigned int size)
+{
+ struct page *pages;
+
+ if (size <= PAGE_SIZE)
+ return kcalloc(size, 1, GFP_KERNEL);
+
+ pages = alloc_pages(GFP_KERNEL|__GFP_ZERO, get_order(size));
+ if (!pages)
+ return NULL;
+
+ return page_address(pages);
+}
+
+static void __tnode_free_rcu(struct rcu_head *head)
+{
+ struct tnode *tn = container_of(head, struct tnode, rcu);
+ unsigned int size = sizeof(struct tnode) +
+ (1 << tn->bits) * sizeof(struct node *);
+
+ if (size <= PAGE_SIZE)
+ kfree(tn);
+ else
+ free_pages((unsigned long)tn, get_order(size));
+}
+
+static inline void tnode_free(struct tnode *tn)
+{
+ call_rcu(&tn->rcu, __tnode_free_rcu);
+}
+
static struct leaf *leaf_new(void)
{
struct leaf *l = kmalloc(sizeof(struct leaf), GFP_KERNEL);
if (l) {
- NODE_INIT_PARENT(l, T_LEAF);
+ l->parent = T_LEAF;
INIT_HLIST_HEAD(&l->list);
}
return l;
@@ -305,45 +364,11 @@
static struct leaf_info *leaf_info_new(int plen)
{
struct leaf_info *li = kmalloc(sizeof(struct leaf_info), GFP_KERNEL);
-
- if (!li)
- return NULL;
-
- li->plen = plen;
- INIT_LIST_HEAD(&li->falh);
-
- return li;
-}
-
-static inline void free_leaf(struct leaf *l)
-{
- kfree(l);
-}
-
-static inline void free_leaf_info(struct leaf_info *li)
-{
- kfree(li);
-}
-
-static struct tnode *tnode_alloc(unsigned int size)
-{
- if (size <= PAGE_SIZE) {
- return kmalloc(size, GFP_KERNEL);
- } else {
- return (struct tnode *)
- __get_free_pages(GFP_KERNEL, get_order(size));
+ if (li) {
+ li->plen = plen;
+ INIT_LIST_HEAD(&li->falh);
}
-}
-
-static void __tnode_free(struct tnode *tn)
-{
- unsigned int size = sizeof(struct tnode) +
- (1 << tn->bits) * sizeof(struct node *);
-
- if (size <= PAGE_SIZE)
- kfree(tn);
- else
- free_pages((unsigned long)tn, get_order(size));
+ return li;
}
static struct tnode* tnode_new(t_key key, int pos, int bits)
@@ -354,7 +379,7 @@
if (tn) {
memset(tn, 0, sz);
- NODE_INIT_PARENT(tn, T_TNODE);
+ tn->parent = T_TNODE;
tn->pos = pos;
tn->bits = bits;
tn->key = key;
@@ -367,17 +392,6 @@
return tn;
}
-static void tnode_free(struct tnode *tn)
-{
- if (IS_LEAF(tn)) {
- free_leaf((struct leaf *)tn);
- pr_debug("FL %p \n", tn);
- } else {
- __tnode_free(tn);
- pr_debug("FT %p \n", tn);
- }
-}
-
/*
* Check whether a tnode 'n' is "full", i.e. it is an internal node
* and no bits are skipped. See discussion in dyntree paper p. 6
@@ -403,13 +417,11 @@
static void tnode_put_child_reorg(struct tnode *tn, int i, struct node *n, int wasfull)
{
- struct node *chi;
+ struct node *chi = tn->child[i];
int isfull;
BUG_ON(i >= 1<<tn->bits);
- write_lock_bh(&fib_lock);
- chi = tn->child[i];
/* update emptyChildren */
if (n == NULL && chi != NULL)
@@ -430,8 +442,7 @@
if (n)
NODE_SET_PARENT(n, tn);
- tn->child[i] = n;
- write_unlock_bh(&fib_lock);
+ rcu_assign_pointer(tn->child[i], n);
}
static struct node *resize(struct trie *t, struct tnode *tn)
@@ -456,17 +467,12 @@
for (i = 0; i < tnode_child_length(tn); i++) {
struct node *n;
- write_lock_bh(&fib_lock);
n = tn->child[i];
- if (!n) {
- write_unlock_bh(&fib_lock);
+ if (!n)
continue;
- }
/* compress one level */
- NODE_INIT_PARENT(n, NODE_TYPE(n));
-
- write_unlock_bh(&fib_lock);
+ NODE_SET_PARENT(n, NULL);
tnode_free(tn);
return n;
}
@@ -577,24 +583,17 @@
/* Only one child remains */
-
if (tn->empty_children == tnode_child_length(tn) - 1)
for (i = 0; i < tnode_child_length(tn); i++) {
struct node *n;
- write_lock_bh(&fib_lock);
-
n = tn->child[i];
- if (!n) {
- write_unlock_bh(&fib_lock);
+ if (!n)
continue;
- }
/* compress one level */
- NODE_INIT_PARENT(n, NODE_TYPE(n));
-
- write_unlock_bh(&fib_lock);
+ NODE_SET_PARENT(n, NULL);
tnode_free(tn);
return n;
}
@@ -831,19 +830,22 @@
return;
t->size = 0;
- t->trie = NULL;
+ rcu_assign_pointer(t->trie, NULL);
t->revision = 0;
#ifdef CONFIG_IP_FIB_TRIE_STATS
memset(&t->stats, 0, sizeof(struct trie_use_stats));
#endif
}
+/* readside most use rcu_read_lock currently dump routines
+ via get_fa_head and dump */
+
static struct leaf_info *find_leaf_info(struct hlist_head *head, int plen)
{
struct hlist_node *node;
struct leaf_info *li;
- hlist_for_each_entry(li, node, head, hlist)
+ hlist_for_each_entry_rcu(li, node, head, hlist)
if (li->plen == plen)
return li;
@@ -862,28 +864,27 @@
static void insert_leaf_info(struct hlist_head *head, struct leaf_info *new)
{
- struct leaf_info *li = NULL, *last = NULL;
- struct hlist_node *node;
+ struct leaf_info *li = NULL, *last = NULL;
+ struct hlist_node *node;
- write_lock_bh(&fib_lock);
+ if (hlist_empty(head)) {
+ hlist_add_head_rcu(&new->hlist, head);
+ } else {
+ hlist_for_each_entry(li, node, head, hlist) {
+ if (new->plen > li->plen)
+ break;
- if (hlist_empty(head)) {
- hlist_add_head(&new->hlist, head);
- } else {
- hlist_for_each_entry(li, node, head, hlist) {
- if (new->plen > li->plen)
- break;
-
- last = li;
- }
- if (last)
- hlist_add_after(&last->hlist, &new->hlist);
- else
- hlist_add_before(&new->hlist, &li->hlist);
- }
- write_unlock_bh(&fib_lock);
+ last = li;
+ }
+ if (last)
+ hlist_add_after_rcu(&last->hlist, &new->hlist);
+ else
+ hlist_add_before_rcu(&new->hlist, &li->hlist);
+ }
}
+/* rcu_read_lock needs to be hold by caller from readside */
+
static struct leaf *
fib_find_node(struct trie *t, u32 key)
{
@@ -892,7 +893,7 @@
struct node *n;
pos = 0;
- n = t->trie;
+ n = rcu_dereference(t->trie);
while (n != NULL && NODE_TYPE(n) == T_TNODE) {
tn = (struct tnode *) n;
@@ -915,17 +916,13 @@
static struct node *trie_rebalance(struct trie *t, struct tnode *tn)
{
- int i;
int wasfull;
t_key cindex, key;
struct tnode *tp = NULL;
key = tn->key;
- i = 0;
while (tn != NULL && NODE_PARENT(tn) != NULL) {
- BUG_ON(i > 12); /* Why is this a bug? -ojn */
- i++;
tp = NODE_PARENT(tn);
cindex = tkey_extract_bits(key, tp->pos, tp->bits);
@@ -945,6 +942,8 @@
return (struct node*) tn;
}
+/* only used from updater-side */
+
static struct list_head *
fib_insert_node(struct trie *t, int *err, u32 key, int plen)
{
@@ -1081,7 +1080,7 @@
cindex = tkey_extract_bits(key, tp->pos, tp->bits);
put_child(t, (struct tnode *)tp, cindex, (struct node *)tn);
} else {
- t->trie = (struct node*) tn; /* First tnode */
+ rcu_assign_pointer(t->trie, (struct node *)tn); /* First tnode */
tp = tn;
}
}
@@ -1091,7 +1090,8 @@
tp, tp->pos, tp->bits, key, plen);
/* Rebalance the trie */
- t->trie = trie_rebalance(t, tp);
+
+ rcu_assign_pointer(t->trie, trie_rebalance(t, tp));
done:
t->revision++;
err:
@@ -1166,16 +1166,21 @@
struct fib_info *fi_drop;
u8 state;
- write_lock_bh(&fib_lock);
+ err = -ENOBUFS;
+ new_fa = kmem_cache_alloc(fn_alias_kmem, SLAB_KERNEL);
+ if (new_fa == NULL)
+ goto out;
fi_drop = fa->fa_info;
- fa->fa_info = fi;
- fa->fa_type = type;
- fa->fa_scope = r->rtm_scope;
+ new_fa->fa_tos = fa->fa_tos;
+ new_fa->fa_info = fi;
+ new_fa->fa_type = type;
+ new_fa->fa_scope = r->rtm_scope;
state = fa->fa_state;
- fa->fa_state &= ~FA_S_ACCESSED;
+ new_fa->fa_state &= ~FA_S_ACCESSED;
- write_unlock_bh(&fib_lock);
+ list_replace_rcu(&fa->fa_list, &new_fa->fa_list);
+ alias_free_mem_rcu(fa);
fib_release_info(fi_drop);
if (state & FA_S_ACCESSED)
@@ -1227,11 +1232,8 @@
goto out_free_new_fa;
}
- write_lock_bh(&fib_lock);
-
- list_add_tail(&new_fa->fa_list, (fa ? &fa->fa_list : fa_head));
-
- write_unlock_bh(&fib_lock);
+ list_add_tail_rcu(&new_fa->fa_list,
+ (fa ? &fa->fa_list : fa_head));
rt_cache_flush(-1);
rtmsg_fib(RTM_NEWROUTE, htonl(key), new_fa, plen, tb->tb_id, nlhdr, req);
@@ -1246,6 +1248,8 @@
return err;
}
+
+/* should be clalled with rcu_read_lock */
static inline int check_leaf(struct trie *t, struct leaf *l,
t_key key, int *plen, const struct flowi *flp,
struct fib_result *res)
@@ -1256,7 +1260,7 @@
struct hlist_head *hhead = &l->list;
struct hlist_node *node;
- hlist_for_each_entry(li, node, hhead, hlist) {
+ hlist_for_each_entry_rcu(li, node, hhead, hlist) {
i = li->plen;
mask = ntohl(inet_make_mask(i));
if (l->key != (key & mask))
@@ -1292,10 +1296,9 @@
t_key node_prefix, key_prefix, pref_mismatch;
int mp;
- n = t->trie;
+ rcu_read_lock();
- read_lock(&fib_lock);
-
+ n = rcu_dereference(t->trie);
if (!n)
goto failed;
@@ -1465,10 +1468,11 @@
failed:
ret = 1;
found:
- read_unlock(&fib_lock);
+ rcu_read_unlock();
return ret;
}
+/* only called from updater side */
static int trie_leaf_remove(struct trie *t, t_key key)
{
t_key cindex;
@@ -1503,15 +1507,17 @@
t->revision++;
t->size--;
+ preempt_disable();
tp = NODE_PARENT(n);
tnode_free((struct tnode *) n);
if (tp) {
cindex = tkey_extract_bits(key, tp->pos, tp->bits);
put_child(t, (struct tnode *)tp, cindex, NULL);
- t->trie = trie_rebalance(t, tp);
+ rcu_assign_pointer(t->trie, trie_rebalance(t, tp));
} else
- t->trie = NULL;
+ rcu_assign_pointer(t->trie, NULL);
+ preempt_enable();
return 1;
}
@@ -1527,7 +1533,6 @@
struct fib_alias *fa, *fa_to_delete;
struct list_head *fa_head;
struct leaf *l;
- int kill_li = 0;
struct leaf_info *li;
@@ -1560,6 +1565,7 @@
fa_to_delete = NULL;
fa_head = fa->fa_list.prev;
+
list_for_each_entry(fa, fa_head, fa_list) {
struct fib_info *fi = fa->fa_info;
@@ -1587,18 +1593,12 @@
l = fib_find_node(t, key);
li = find_leaf_info(&l->list, plen);
- write_lock_bh(&fib_lock);
-
- list_del(&fa->fa_list);
+ list_del_rcu(&fa->fa_list);
if (list_empty(fa_head)) {
- hlist_del(&li->hlist);
- kill_li = 1;
- }
- write_unlock_bh(&fib_lock);
-
- if (kill_li)
+ hlist_del_rcu(&li->hlist);
free_leaf_info(li);
+ }
if (hlist_empty(&l->list))
trie_leaf_remove(t, key);
@@ -1606,7 +1606,8 @@
if (fa->fa_state & FA_S_ACCESSED)
rt_cache_flush(-1);
- fn_free_alias(fa);
+ fib_release_info(fa->fa_info);
+ alias_free_mem_rcu(fa);
return 0;
}
@@ -1618,12 +1619,10 @@
list_for_each_entry_safe(fa, fa_node, head, fa_list) {
struct fib_info *fi = fa->fa_info;
- if (fi && (fi->fib_flags&RTNH_F_DEAD)) {
- write_lock_bh(&fib_lock);
- list_del(&fa->fa_list);
- write_unlock_bh(&fib_lock);
-
- fn_free_alias(fa);
+ if (fi && (fi->fib_flags & RTNH_F_DEAD)) {
+ list_del_rcu(&fa->fa_list);
+ fib_release_info(fa->fa_info);
+ alias_free_mem_rcu(fa);
found++;
}
}
@@ -1641,30 +1640,30 @@
found += trie_flush_list(t, &li->falh);
if (list_empty(&li->falh)) {
- write_lock_bh(&fib_lock);
- hlist_del(&li->hlist);
- write_unlock_bh(&fib_lock);
-
+ hlist_del_rcu(&li->hlist);
free_leaf_info(li);
}
}
return found;
}
+/* rcu_read_lock needs to be hold by caller from readside */
+
static struct leaf *nextleaf(struct trie *t, struct leaf *thisleaf)
{
struct node *c = (struct node *) thisleaf;
struct tnode *p;
int idx;
+ struct node *trie = rcu_dereference(t->trie);
if (c == NULL) {
- if (t->trie == NULL)
+ if (trie == NULL)
return NULL;
- if (IS_LEAF(t->trie)) /* trie w. just a leaf */
- return (struct leaf *) t->trie;
+ if (IS_LEAF(trie)) /* trie w. just a leaf */
+ return (struct leaf *) trie;
- p = (struct tnode*) t->trie; /* Start */
+ p = (struct tnode*) trie; /* Start */
} else
p = (struct tnode *) NODE_PARENT(c);
@@ -1679,23 +1678,26 @@
last = 1 << p->bits;
for (idx = pos; idx < last ; idx++) {
- if (!p->child[idx])
+ c = rcu_dereference(p->child[idx]);
+
+ if (!c)
continue;
/* Decend if tnode */
- while (IS_TNODE(p->child[idx])) {
- p = (struct tnode*) p->child[idx];
- idx = 0;
+ while (IS_TNODE(c)) {
+ p = (struct tnode *) c;
+ idx = 0;
/* Rightmost non-NULL branch */
if (p && IS_TNODE(p))
- while (p->child[idx] == NULL && idx < (1 << p->bits)) idx++;
+ while (!(c = rcu_dereference(p->child[idx]))
+ && idx < (1<<p->bits)) idx++;
/* Done with this tnode? */
- if (idx >= (1 << p->bits) || p->child[idx] == NULL)
+ if (idx >= (1 << p->bits) || !c)
goto up;
}
- return (struct leaf*) p->child[idx];
+ return (struct leaf *) c;
}
up:
/* No more children go up one step */
@@ -1713,6 +1715,7 @@
t->revision++;
+ rcu_read_lock();
for (h = 0; (l = nextleaf(t, l)) != NULL; h++) {
found += trie_flush_leaf(t, l);
@@ -1720,6 +1723,7 @@
trie_leaf_remove(t, ll->key);
ll = l;
}
+ rcu_read_unlock();
if (ll && hlist_empty(&ll->list))
trie_leaf_remove(t, ll->key);
@@ -1745,7 +1749,7 @@
last_resort = NULL;
order = -1;
- read_lock(&fib_lock);
+ rcu_read_lock();
l = fib_find_node(t, 0);
if (!l)
@@ -1758,7 +1762,7 @@
if (list_empty(fa_head))
goto out;
- list_for_each_entry(fa, fa_head, fa_list) {
+ list_for_each_entry_rcu(fa, fa_head, fa_list) {
struct fib_info *next_fi = fa->fa_info;
if (fa->fa_scope != res->scope ||
@@ -1809,7 +1813,7 @@
}
trie_last_dflt = last_idx;
out:;
- read_unlock(&fib_lock);
+ rcu_read_unlock();
}
static int fn_trie_dump_fa(t_key key, int plen, struct list_head *fah, struct fib_table *tb,
@@ -1823,7 +1827,9 @@
s_i = cb->args[3];
i = 0;
- list_for_each_entry(fa, fah, fa_list) {
+ /* rcu_read_lock is hold by caller */
+
+ list_for_each_entry_rcu(fa, fah, fa_list) {
if (i < s_i) {
i++;
continue;
@@ -1898,7 +1904,7 @@
s_m = cb->args[1];
- read_lock(&fib_lock);
+ rcu_read_lock();
for (m = 0; m <= 32; m++) {
if (m < s_m)
continue;
@@ -1911,11 +1917,11 @@
goto out;
}
}
- read_unlock(&fib_lock);
+ rcu_read_unlock();
cb->args[1] = m;
return skb->len;
out:
- read_unlock(&fib_lock);
+ rcu_read_unlock();
return -1;
}
@@ -2016,7 +2022,7 @@
putspace_seq(seq, indent+2);
seq_printf(seq, "{/%d...dumping}\n", i);
- list_for_each_entry(fa, fa_head, fa_list) {
+ list_for_each_entry_rcu(fa, fa_head, fa_list) {
putspace_seq(seq, indent+2);
if (fa->fa_info == NULL) {
seq_printf(seq, "Error fa_info=NULL\n");
@@ -2056,28 +2062,28 @@
static void trie_dump_seq(struct seq_file *seq, struct trie *t)
{
- struct node *n = t->trie;
+ struct node *n;
int cindex = 0;
int indent = 1;
int pend = 0;
int depth = 0;
struct tnode *tn;
- read_lock(&fib_lock);
-
+ rcu_read_lock();
+ n = rcu_dereference(t->trie);
seq_printf(seq, "------ trie_dump of t=%p ------\n", t);
if (!n) {
seq_printf(seq, "------ trie is empty\n");
- read_unlock(&fib_lock);
+ rcu_read_unlock();
return;
}
printnode_seq(seq, indent, n, pend, cindex, 0);
if (!IS_TNODE(n)) {
- read_unlock(&fib_lock);
+ rcu_read_unlock();
return;
}
@@ -2088,26 +2094,32 @@
depth++;
while (tn && cindex < (1 << tn->bits)) {
- if (tn->child[cindex]) {
+ struct node *child = rcu_dereference(tn->child[cindex]);
+ if (!child)
+ cindex++;
+ else {
/* Got a child */
+ printnode_seq(seq, indent, child, pend,
+ cindex, tn->bits);
- printnode_seq(seq, indent, tn->child[cindex], pend, cindex, tn->bits);
- if (IS_LEAF(tn->child[cindex])) {
+ if (IS_LEAF(child))
cindex++;
- } else {
+
+ else {
/*
* New tnode. Decend one level
*/
depth++;
- tn = (struct tnode *)tn->child[cindex];
- pend = tn->pos + tn->bits;
- putspace_seq(seq, indent); seq_printf(seq, "\\--\n");
+ n = child;
+ tn = (struct tnode *)n;
+ pend = tn->pos+tn->bits;
+ putspace_seq(seq, indent);
+ seq_printf(seq, "\\--\n");
indent += 3;
cindex = 0;
}
- } else
- cindex++;
+ }
/*
* Test if we are done
@@ -2132,8 +2144,7 @@
depth--;
}
}
-
- read_unlock(&fib_lock);
+ rcu_read_unlock();
}
static struct trie_stat *trie_stat_new(void)
@@ -2159,7 +2170,7 @@
static struct trie_stat *trie_collect_stats(struct trie *t)
{
- struct node *n = t->trie;
+ struct node *n;
struct trie_stat *s = trie_stat_new();
int cindex = 0;
int pend = 0;
@@ -2167,11 +2178,13 @@
if (!s)
return NULL;
+
+ rcu_read_lock();
+ n = rcu_dereference(t->trie);
+
if (!n)
return s;
- read_lock(&fib_lock);
-
if (IS_TNODE(n)) {
struct tnode *tn = (struct tnode *)n;
pend = tn->pos+tn->bits;
@@ -2179,7 +2192,9 @@
depth++;
while (tn && cindex < (1 << tn->bits)) {
- if (tn->child[cindex]) {
+ struct node *ch = rcu_dereference(tn->child[cindex]);
+ if (ch) {
+
/* Got a child */
if (IS_LEAF(tn->child[cindex])) {
@@ -2199,7 +2214,7 @@
s->nodesizes[tn->bits]++;
depth++;
- n = tn->child[cindex];
+ n = ch;
tn = (struct tnode *)n;
pend = tn->pos+tn->bits;
@@ -2236,7 +2251,7 @@
}
}
- read_unlock(&fib_lock);
+ rcu_read_unlock();
return s;
}
