Skip to content

Commit

Permalink
ipv6: take care of rt6_stats
Browse files Browse the repository at this point in the history 
Currently, most of the rt6_stats are not hooked up correctly. As the
last part of this patch series, hook up all existing rt6_stats and add
one new stat fib_rt_uncache to indicate the number of routes in the
uncached list.
For details of the stats, please refer to the comments added in
include/net/ip6_fib.h.

Note: fib_rt_alloc and fib_rt_uncache are not guaranteed to be modified
under a lock. So atomic_t is used for them.

Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
  • Loading branch information
Wei Wang authored and David S. Miller committed Oct 7, 2017
1 parent 66f5d6c commit 81eb844
Show file tree
Hide file tree
Showing 3 changed files with 47 additions and 26 deletions.
15 changes: 9 additions & 6 deletions include/net/ip6_fib.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -297,12 +297,15 @@ struct fib6_walker {
};

struct rt6_statistics {
__u32 fib_nodes;
__u32 fib_route_nodes;
__u32 fib_rt_alloc; /* permanent routes */
__u32 fib_rt_entries; /* rt entries in table */
__u32 fib_rt_cache; /* cache routes */
__u32 fib_discarded_routes;
__u32 fib_nodes; /* all fib6 nodes */
__u32 fib_route_nodes; /* intermediate nodes */
__u32 fib_rt_entries; /* rt entries in fib table */
__u32 fib_rt_cache; /* cached rt entries in exception table */
__u32 fib_discarded_routes; /* total number of routes delete */

/* The following stats are not protected by any lock */
atomic_t fib_rt_alloc; /* total number of routes alloced */
atomic_t fib_rt_uncache; /* rt entries in uncached list */
};

#define RTN_TL_ROOT 0x0001
Expand Down
42 changes: 24 additions & 18 deletions net/ipv6/ip6_fib.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -149,18 +149,21 @@ static __be32 addr_bit_set(const void *token, int fn_bit)
addr[fn_bit >> 5];
}

static struct fib6_node *node_alloc(void)
static struct fib6_node *node_alloc(struct net *net)
{
struct fib6_node *fn;

fn = kmem_cache_zalloc(fib6_node_kmem, GFP_ATOMIC);
if (fn)
net->ipv6.rt6_stats->fib_nodes++;

return fn;
}

static void node_free_immediate(struct fib6_node *fn)
static void node_free_immediate(struct net *net, struct fib6_node *fn)
{
kmem_cache_free(fib6_node_kmem, fn);
net->ipv6.rt6_stats->fib_nodes--;
}

static void node_free_rcu(struct rcu_head *head)
Expand All @@ -170,9 +173,10 @@ static void node_free_rcu(struct rcu_head *head)
kmem_cache_free(fib6_node_kmem, fn);
}

static void node_free(struct fib6_node *fn)
static void node_free(struct net *net, struct fib6_node *fn)
{
call_rcu(&fn->rcu, node_free_rcu);
net->ipv6.rt6_stats->fib_nodes--;
}

void rt6_free_pcpu(struct rt6_info *non_pcpu_rt)
Expand Down Expand Up @@ -583,7 +587,8 @@ static int inet6_dump_fib(struct sk_buff *skb, struct netlink_callback *cb)
* node.
*/

static struct fib6_node *fib6_add_1(struct fib6_table *table,
static struct fib6_node *fib6_add_1(struct net *net,
struct fib6_table *table,
struct fib6_node *root,
struct in6_addr *addr, int plen,
int offset, int allow_create,
Expand Down Expand Up @@ -675,7 +680,7 @@ static struct fib6_node *fib6_add_1(struct fib6_table *table,
* Create new leaf node without children.
*/

ln = node_alloc();
ln = node_alloc(net);

if (!ln)
return ERR_PTR(-ENOMEM);
Expand Down Expand Up @@ -716,14 +721,14 @@ static struct fib6_node *fib6_add_1(struct fib6_table *table,
* (new leaf node)[ln] (old node)[fn]
*/
if (plen > bit) {
in = node_alloc();
ln = node_alloc();
in = node_alloc(net);
ln = node_alloc(net);

if (!in || !ln) {
if (in)
node_free_immediate(in);
node_free_immediate(net, in);
if (ln)
node_free_immediate(ln);
node_free_immediate(net, ln);
return ERR_PTR(-ENOMEM);
}

Expand Down Expand Up @@ -768,7 +773,7 @@ static struct fib6_node *fib6_add_1(struct fib6_table *table,
* (old node)[fn] NULL
*/

ln = node_alloc();
ln = node_alloc(net);

if (!ln)
return ERR_PTR(-ENOMEM);
Expand Down Expand Up @@ -1065,6 +1070,7 @@ static int fib6_add_rt2node(struct fib6_node *fn, struct rt6_info *rt,
fn->rr_ptr = NULL;
rt6_release(iter);
nsiblings--;
info->nl_net->ipv6.rt6_stats->fib_rt_entries--;
} else {
ins = &iter->dst.rt6_next;
}
Expand Down Expand Up @@ -1140,7 +1146,7 @@ int fib6_add(struct fib6_node *root, struct rt6_info *rt,
if (!allow_create && !replace_required)
pr_warn("RTM_NEWROUTE with no NLM_F_CREATE or NLM_F_REPLACE\n");

fn = fib6_add_1(table, root,
fn = fib6_add_1(info->nl_net, table, root,
&rt->rt6i_dst.addr, rt->rt6i_dst.plen,
offsetof(struct rt6_info, rt6i_dst), allow_create,
replace_required, extack);
Expand Down Expand Up @@ -1170,7 +1176,7 @@ int fib6_add(struct fib6_node *root, struct rt6_info *rt,
*/

/* Create subtree root node */
sfn = node_alloc();
sfn = node_alloc(info->nl_net);
if (!sfn)
goto failure;

Expand All @@ -1181,8 +1187,8 @@ int fib6_add(struct fib6_node *root, struct rt6_info *rt,

/* Now add the first leaf node to new subtree */

sn = fib6_add_1(table, sfn, &rt->rt6i_src.addr,
rt->rt6i_src.plen,
sn = fib6_add_1(info->nl_net, table, sfn,
&rt->rt6i_src.addr, rt->rt6i_src.plen,
offsetof(struct rt6_info, rt6i_src),
allow_create, replace_required, extack);

Expand All @@ -1191,7 +1197,7 @@ int fib6_add(struct fib6_node *root, struct rt6_info *rt,
root, and then (in failure) stale node
in main tree.
*/
node_free_immediate(sfn);
node_free_immediate(info->nl_net, sfn);
err = PTR_ERR(sn);
goto failure;
}
Expand All @@ -1200,8 +1206,8 @@ int fib6_add(struct fib6_node *root, struct rt6_info *rt,
rcu_assign_pointer(sfn->parent, fn);
rcu_assign_pointer(fn->subtree, sfn);
} else {
sn = fib6_add_1(table, FIB6_SUBTREE(fn), &rt->rt6i_src.addr,
rt->rt6i_src.plen,
sn = fib6_add_1(info->nl_net, table, FIB6_SUBTREE(fn),
&rt->rt6i_src.addr, rt->rt6i_src.plen,
offsetof(struct rt6_info, rt6i_src),
allow_create, replace_required, extack);

Expand Down Expand Up @@ -1609,7 +1615,7 @@ static struct fib6_node *fib6_repair_tree(struct net *net,
}
read_unlock(&net->ipv6.fib6_walker_lock);

node_free(fn);
node_free(net, fn);
if (pn->fn_flags & RTN_RTINFO || FIB6_SUBTREE(pn))
return pn;

Expand Down
16 changes: 14 additions & 2 deletions net/ipv6/route.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -143,9 +143,11 @@ static void rt6_uncached_list_del(struct rt6_info *rt)
{
if (!list_empty(&rt->rt6i_uncached)) {
struct uncached_list *ul = rt->rt6i_uncached_list;
struct net *net = dev_net(rt->dst.dev);

spin_lock_bh(&ul->lock);
list_del(&rt->rt6i_uncached);
atomic_dec(&net->ipv6.rt6_stats->fib_rt_uncache);
spin_unlock_bh(&ul->lock);
}
}
Expand Down Expand Up @@ -359,8 +361,10 @@ static struct rt6_info *__ip6_dst_alloc(struct net *net,
struct rt6_info *rt = dst_alloc(&net->ipv6.ip6_dst_ops, dev,
1, DST_OBSOLETE_FORCE_CHK, flags);

if (rt)
if (rt) {
rt6_info_init(rt);
atomic_inc(&net->ipv6.rt6_stats->fib_rt_alloc);
}

return rt;
}
Expand Down Expand Up @@ -1156,6 +1160,8 @@ static DEFINE_SPINLOCK(rt6_exception_lock);
static void rt6_remove_exception(struct rt6_exception_bucket *bucket,
struct rt6_exception *rt6_ex)
{
struct net *net = dev_net(rt6_ex->rt6i->dst.dev);

if (!bucket || !rt6_ex)
return;
rt6_ex->rt6i->rt6i_node = NULL;
Expand All @@ -1164,6 +1170,7 @@ static void rt6_remove_exception(struct rt6_exception_bucket *bucket,
kfree_rcu(rt6_ex, rcu);
WARN_ON_ONCE(!bucket->depth);
bucket->depth--;
net->ipv6.rt6_stats->fib_rt_cache--;
}

/* Remove oldest rt6_ex in bucket and free the memory
Expand Down Expand Up @@ -1270,6 +1277,7 @@ __rt6_find_exception_rcu(struct rt6_exception_bucket **bucket,
static int rt6_insert_exception(struct rt6_info *nrt,
struct rt6_info *ort)
{
struct net *net = dev_net(ort->dst.dev);
struct rt6_exception_bucket *bucket;
struct in6_addr *src_key = NULL;
struct rt6_exception *rt6_ex;
Expand Down Expand Up @@ -1339,6 +1347,7 @@ static int rt6_insert_exception(struct rt6_info *nrt,
nrt->rt6i_node = ort->rt6i_node;
hlist_add_head_rcu(&rt6_ex->hlist, &bucket->chain);
bucket->depth++;
net->ipv6.rt6_stats->fib_rt_cache++;

if (bucket->depth > FIB6_MAX_DEPTH)
rt6_exception_remove_oldest(bucket);
Expand Down Expand Up @@ -1714,6 +1723,7 @@ struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table,
* No need for another dst_hold()
*/
rt6_uncached_list_add(uncached_rt);
atomic_inc(&net->ipv6.rt6_stats->fib_rt_uncache);
} else {
uncached_rt = net->ipv6.ip6_null_entry;
dst_hold(&uncached_rt->dst);
Expand Down Expand Up @@ -1894,6 +1904,7 @@ struct dst_entry *ip6_blackhole_route(struct net *net, struct dst_entry *dst_ori
DST_OBSOLETE_NONE, 0);
if (rt) {
rt6_info_init(rt);
atomic_inc(&net->ipv6.rt6_stats->fib_rt_alloc);

new = &rt->dst;
new->__use = 1;
Expand Down Expand Up @@ -2341,6 +2352,7 @@ struct dst_entry *icmp6_dst_alloc(struct net_device *dev,
* do proper release of the net_device
*/
rt6_uncached_list_add(rt);
atomic_inc(&net->ipv6.rt6_stats->fib_rt_uncache);

dst = xfrm_lookup(net, &rt->dst, flowi6_to_flowi(fl6), NULL, 0);

Expand Down Expand Up @@ -4422,7 +4434,7 @@ static int rt6_stats_seq_show(struct seq_file *seq, void *v)
seq_printf(seq, "%04x %04x %04x %04x %04x %04x %04x\n",
net->ipv6.rt6_stats->fib_nodes,
net->ipv6.rt6_stats->fib_route_nodes,
net->ipv6.rt6_stats->fib_rt_alloc,
atomic_read(&net->ipv6.rt6_stats->fib_rt_alloc),
net->ipv6.rt6_stats->fib_rt_entries,
net->ipv6.rt6_stats->fib_rt_cache,
dst_entries_get_slow(&net->ipv6.ip6_dst_ops),
Expand Down

0 comments on commit 81eb844

Please sign in to comment.