[RFC PATCH 01/29] fib_trie: Convert fib_alias to hlist from list

Alexander Duyck
2015-02-24T20:48:03Z

There isn't any advantage to having it as a list and by making it an hlist
we make the fib_alias more compatible with the list_info in terms of the
type of list used.

Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com>
---
include/net/ip_fib.h | 2 +
net/ipv4/fib_lookup.h | 2 +
net/ipv4/fib_semantics.c | 4 +--
net/ipv4/fib_trie.c | 72 ++++++++++++++++++++++++++--------------------
4 files changed, 44 insertions(+), 36 deletions(-)

diff --git a/include/net/ip_fib.h b/include/net/ip_fib.h
index 5bd120e..cba4b7c 100644
--- a/include/net/ip_fib.h
+++ b/include/net/ip_fib.h
@@ -136,7 +136,7 @@ struct fib_result {
u32 tclassid;
struct fib_info *fi;
struct fib_table *table;
- struct list_head *fa_head;
+ struct hlist_head *fa_head;
};

struct fib_result_nl {
diff --git a/net/ipv4/fib_lookup.h b/net/ipv4/fib_lookup.h
index 825981b..3cd444f 100644
--- a/net/ipv4/fib_lookup.h
+++ b/net/ipv4/fib_lookup.h
@@ -6,7 +6,7 @@
#include <net/ip_fib.h>

struct fib_alias {
- struct list_head fa_list;
+ struct hlist_node fa_list;
struct fib_info *fa_info;
u8 fa_tos;
u8 fa_type;
diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c
index 1e2090e..c6d2674 100644
--- a/net/ipv4/fib_semantics.c
+++ b/net/ipv4/fib_semantics.c
@@ -1163,12 +1163,12 @@ int fib_sync_down_dev(struct net_device *dev, int force)
void fib_select_default(struct fib_result *res)
{
struct fib_info *fi = NULL, *last_resort = NULL;
- struct list_head *fa_head = res->fa_head;
+ struct hlist_head *fa_head = res->fa_head;
struct fib_table *tb = res->table;
int order = -1, last_idx = -1;
struct fib_alias *fa;

- list_for_each_entry_rcu(fa, fa_head, fa_list) {
+ hlist_for_each_entry_rcu(fa, fa_head, fa_list) {
struct fib_info *next_fi = fa->fa_info;

if (next_fi->fib_scope != res->scope ||
diff --git a/net/ipv4/fib_trie.c b/net/ipv4/fib_trie.c
index 3daf022..e0d44b7 100644
--- a/net/ipv4/fib_trie.c
+++ b/net/ipv4/fib_trie.c
@@ -116,7 +116,7 @@ struct leaf_info {
struct hlist_node hlist;
int plen;
u32 mask_plen; /* ntohl(inet_make_mask(plen)) */
- struct list_head falh;
+ struct hlist_head falh;
struct rcu_head rcu;
};

@@ -339,7 +339,7 @@ static struct leaf_info *leaf_info_new(int plen)
if (li) {
li->plen = plen;
li->mask_plen = ntohl(inet_make_mask(plen));
- INIT_LIST_HEAD(&li->falh);
+ INIT_HLIST_HEAD(&li->falh);
}
return li;
}
@@ -881,7 +881,7 @@ static struct leaf_info *find_leaf_info(struct tnode *l, int plen)
return NULL;
}

-static inline struct list_head *get_fa_head(struct tnode *l, int plen)
+static inline struct hlist_head *get_fa_head(struct tnode *l, int plen)
{
struct leaf_info *li = find_leaf_info(l, plen);

@@ -994,14 +994,15 @@ static struct tnode *fib_find_node(struct trie *t, u32 key)
/* Return the first fib alias matching TOS with
* priority less than or equal to PRIO.
*/
-static struct fib_alias *fib_find_alias(struct list_head *fah, u8 tos, u32 prio)
+static struct fib_alias *fib_find_alias(struct hlist_head *fah, u8 tos,
+ u32 prio)
{
struct fib_alias *fa;

if (!fah)
return NULL;

- list_for_each_entry(fa, fah, fa_list) {
+ hlist_for_each_entry(fa, fah, fa_list) {
if (fa->fa_tos > tos)
continue;
if (fa->fa_info->fib_priority >= prio || fa->fa_tos < tos)
@@ -1027,9 +1028,9 @@ static void trie_rebalance(struct trie *t, struct tnode *tn)

/* only used from updater-side */

-static struct list_head *fib_insert_node(struct trie *t, u32 key, int plen)
+static struct hlist_head *fib_insert_node(struct trie *t, u32 key, int plen)
{
- struct list_head *fa_head = NULL;
+ struct hlist_head *fa_head = NULL;
struct tnode *l, *n, *tp = NULL;
struct leaf_info *li;

@@ -1130,7 +1131,7 @@ int fib_table_insert(struct fib_table *tb, struct fib_config *cfg)
{
struct trie *t = (struct trie *) tb->tb_data;
struct fib_alias *fa, *new_fa;
- struct list_head *fa_head = NULL;
+ struct hlist_head *fa_head = NULL;
struct fib_info *fi;
int plen = cfg->fc_dst_len;
u8 tos = cfg->fc_tos;
@@ -1192,8 +1193,7 @@ int fib_table_insert(struct fib_table *tb, struct fib_config *cfg)
*/
fa_match = NULL;
fa_first = fa;
- fa = list_entry(fa->fa_list.prev, struct fib_alias, fa_list);
- list_for_each_entry_continue(fa, fa_head, fa_list) {
+ hlist_for_each_entry_from(fa, fa_list) {
if (fa->fa_tos != tos)
break;
if (fa->fa_info->fib_priority != fi->fib_priority)
@@ -1227,7 +1227,7 @@ int fib_table_insert(struct fib_table *tb, struct fib_config *cfg)
state = fa->fa_state;
new_fa->fa_state = state & ~FA_S_ACCESSED;

- list_replace_rcu(&fa->fa_list, &new_fa->fa_list);
+ hlist_replace_rcu(&fa->fa_list, &new_fa->fa_list);
alias_free_mem_rcu(fa);

fib_release_info(fi_drop);
@@ -1276,8 +1276,17 @@ int fib_table_insert(struct fib_table *tb, struct fib_config *cfg)
if (!plen)
tb->tb_num_default++;

- list_add_tail_rcu(&new_fa->fa_list,
- (fa ? &fa->fa_list : fa_head));
+ if (!fa) {
+ struct fib_alias *last;
+
+ hlist_for_each_entry(last, fa_head, fa_list)
+ fa = last;
+ }
+
+ if (fa)
+ hlist_add_behind_rcu(&new_fa->fa_list, &fa->fa_list);
+ else
+ hlist_add_head_rcu(&new_fa->fa_list, fa_head);

rt_cache_flush(cfg->fc_nlinfo.nl_net);
rtmsg_fib(RTM_NEWROUTE, htonl(key), new_fa, plen, tb->tb_id,
@@ -1419,7 +1428,7 @@ found:
if ((key ^ n->key) & li->mask_plen)
continue;

- list_for_each_entry_rcu(fa, &li->falh, fa_list) {
+ hlist_for_each_entry_rcu(fa, &li->falh, fa_list) {
struct fib_info *fi = fa->fa_info;
int nhsel, err;

@@ -1501,7 +1510,7 @@ int fib_table_delete(struct fib_table *tb, struct fib_config *cfg)
int plen = cfg->fc_dst_len;
u8 tos = cfg->fc_tos;
struct fib_alias *fa, *fa_to_delete;
- struct list_head *fa_head;
+ struct hlist_head *fa_head;
struct tnode *l;
struct leaf_info *li;

@@ -1534,8 +1543,7 @@ int fib_table_delete(struct fib_table *tb, struct fib_config *cfg)
pr_debug("Deleting %08x/%d tos=%d t=%p\n", key, plen, tos, t);

fa_to_delete = NULL;
- fa = list_entry(fa->fa_list.prev, struct fib_alias, fa_list);
- list_for_each_entry_continue(fa, fa_head, fa_list) {
+ hlist_for_each_entry_from(fa, fa_list) {
struct fib_info *fi = fa->fa_info;

if (fa->fa_tos != tos)
@@ -1561,12 +1569,12 @@ int fib_table_delete(struct fib_table *tb, struct fib_config *cfg)
rtmsg_fib(RTM_DELROUTE, htonl(key), fa, plen, tb->tb_id,
&cfg->fc_nlinfo, 0);

- list_del_rcu(&fa->fa_list);
+ hlist_del_rcu(&fa->fa_list);

if (!plen)
tb->tb_num_default--;

- if (list_empty(fa_head)) {
+ if (hlist_empty(fa_head)) {
remove_leaf_info(l, li);
free_leaf_info(li);
}
@@ -1582,16 +1590,17 @@ int fib_table_delete(struct fib_table *tb, struct fib_config *cfg)
return 0;
}

-static int trie_flush_list(struct list_head *head)
+static int trie_flush_list(struct hlist_head *head)
{
- struct fib_alias *fa, *fa_node;
+ struct hlist_node *tmp;
+ struct fib_alias *fa;
int found = 0;

- list_for_each_entry_safe(fa, fa_node, head, fa_list) {
+ hlist_for_each_entry_safe(fa, tmp, head, fa_list) {
struct fib_info *fi = fa->fa_info;

if (fi && (fi->fib_flags & RTNH_F_DEAD)) {
- list_del_rcu(&fa->fa_list);
+ hlist_del_rcu(&fa->fa_list);
fib_release_info(fa->fa_info);
alias_free_mem_rcu(fa);
found++;
@@ -1603,15 +1612,14 @@ static int trie_flush_list(struct list_head *head)
static int trie_flush_leaf(struct tnode *l)
{
int found = 0;
- struct hlist_head *lih = &l->list;
struct hlist_node *tmp;
- struct leaf_info *li = NULL;
+ struct leaf_info *li;
unsigned char plen = KEYLENGTH;

- hlist_for_each_entry_safe(li, tmp, lih, hlist) {
+ hlist_for_each_entry_safe(li, tmp, &l->list, hlist) {
found += trie_flush_list(&li->falh);

- if (list_empty(&li->falh)) {
+ if (hlist_empty(&li->falh)) {
hlist_del_rcu(&li->hlist);
free_leaf_info(li);
continue;
@@ -1731,7 +1739,7 @@ void fib_free_table(struct fib_table *tb)
kfree(tb);
}

-static int fn_trie_dump_fa(t_key key, int plen, struct list_head *fah,
+static int fn_trie_dump_fa(t_key key, int plen, struct hlist_head *fah,
struct fib_table *tb,
struct sk_buff *skb, struct netlink_callback *cb)
{
@@ -1744,7 +1752,7 @@ static int fn_trie_dump_fa(t_key key, int plen, struct list_head *fah,

/* rcu_read_lock is hold by caller */

- list_for_each_entry_rcu(fa, fah, fa_list) {
+ hlist_for_each_entry_rcu(fa, fah, fa_list) {
if (i < s_i) {
i++;
continue;
@@ -1787,7 +1795,7 @@ static int fn_trie_dump_leaf(struct tnode *l, struct fib_table *tb,
if (i > s_i)
cb->args[5] = 0;

- if (list_empty(&li->falh))
+ if (hlist_empty(&li->falh))
continue;

if (fn_trie_dump_fa(l->key, li->plen, &li->falh, tb, skb, cb) < 0) {
@@ -2272,7 +2280,7 @@ static int fib_trie_seq_show(struct seq_file *seq, void *v)
hlist_for_each_entry_rcu(li, &n->list, hlist) {
struct fib_alias *fa;

- list_for_each_entry_rcu(fa, &li->falh, fa_list) {
+ hlist_for_each_entry_rcu(fa, &li->falh, fa_list) {
char buf1[32], buf2[32];

seq_indent(seq, iter->depth+1);
@@ -2429,7 +2437,7 @@ static int fib_route_seq_show(struct seq_file *seq, void *v)
mask = inet_make_mask(li->plen);
prefix = htonl(l->key);

- list_for_each_entry_rcu(fa, &li->falh, fa_list) {
+ hlist_for_each_entry_rcu(fa, &li->falh, fa_list) {
const struct fib_info *fi = fa->fa_info;
unsigned int flags = fib_flag_trans(fa->fa_type, mask, fi);