iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

ipv6: prepare fib6_age() for exception table

Browse Source 
If all dst cache entries are stored in the exception table under the
main route, we have to go through them during fib6_age() when doing
garbage collecting.
Introduce a new function rt6_age_exception() which goes through all dst
entries in the exception table and remove those entries that are expired.
This function is called in fib6_age() so that all dst caches are also
garbage collected.

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>
This commit is contained in:
Wei Wang 2017-10-06 12:06:01 -07:00 committed by David S. Miller
parent b16cb459d7
commit c757faa8bf
4 changed files with 84 additions and 17 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

13
include/net/ip6_fib.h
View File

@ -29,6 +29,14 @@
#define FIB6_TABLE_HASHSZ 1
#endif
#define RT6_DEBUG 2
#if RT6_DEBUG >= 3
#define RT6_TRACE(x...) pr_debug(x)
#else
#define RT6_TRACE(x...) do { ; } while (0)
#endif
struct rt6_info;
struct fib6_config {
@ -75,6 +83,11 @@ struct fib6_node {
struct rcu_head rcu;
};
struct fib6_gc_args {
int timeout;
int more;
};
#ifndef CONFIG_IPV6_SUBTREES
#define FIB6_SUBTREE(fn) NULL
#else

2
include/net/ip6_route.h
View File

@ -97,6 +97,8 @@ int ip6_del_rt(struct rt6_info *);
void rt6_flush_exceptions(struct rt6_info *rt);
int rt6_remove_exception_rt(struct rt6_info *rt);
void rt6_age_exceptions(struct rt6_info *rt, struct fib6_gc_args *gc_args,
unsigned long now);
static inline int ip6_route_get_saddr(struct net *net, struct rt6_info *rt,
const struct in6_addr *daddr,

26
net/ipv6/ip6_fib.c
View File

@ -38,14 +38,6 @@
#include <net/ip6_fib.h>
#include <net/ip6_route.h>
#define RT6_DEBUG 2
#if RT6_DEBUG >= 3
#define RT6_TRACE(x...) pr_debug(x)
#else
#define RT6_TRACE(x...) do { ; } while (0)
#endif
static struct kmem_cache *fib6_node_kmem __read_mostly;
struct fib6_cleaner {
@ -1890,12 +1882,6 @@ static void fib6_flush_trees(struct net *net)
* Garbage collection
*/
struct fib6_gc_args
{
int timeout;
int more;
};
static int fib6_age(struct rt6_info *rt, void *arg)
{
struct fib6_gc_args *gc_args = arg;
@ -1904,9 +1890,6 @@ static int fib6_age(struct rt6_info *rt, void *arg)
/*
* check addrconf expiration here.
* Routes are expired even if they are in use.
*
* Also age clones. Note, that clones are aged out
* only if they are not in use now.
*/
if (rt->rt6i_flags & RTF_EXPIRES && rt->dst.expires) {
@ -1915,6 +1898,9 @@ static int fib6_age(struct rt6_info *rt, void *arg)
return -1;
}
gc_args->more++;
/* The following part will soon be removed when the exception
* table is hooked up to store all cached routes.
*/
} else if (rt->rt6i_flags & RTF_CACHE) {
if (time_after_eq(now, rt->dst.lastuse + gc_args->timeout))
rt->dst.obsolete = DST_OBSOLETE_KILL;
@ -1940,6 +1926,12 @@ static int fib6_age(struct rt6_info *rt, void *arg)
gc_args->more++;
}
/* Also age clones in the exception table.
* Note, that clones are aged out
* only if they are not in use now.
*/
rt6_age_exceptions(rt, gc_args, now);
return 0;
}

60
net/ipv6/route.c
View File

@ -1528,6 +1528,66 @@ static void rt6_exceptions_clean_tohost(struct rt6_info *rt,
spin_unlock_bh(&rt6_exception_lock);
}
static void rt6_age_examine_exception(struct rt6_exception_bucket *bucket,
struct rt6_exception *rt6_ex,
struct fib6_gc_args *gc_args,
unsigned long now)
{
struct rt6_info *rt = rt6_ex->rt6i;
if (atomic_read(&rt->dst.__refcnt) == 1 &&
time_after_eq(now, rt->dst.lastuse + gc_args->timeout)) {
RT6_TRACE("aging clone %p\n", rt);
rt6_remove_exception(bucket, rt6_ex);
return;
} else if (rt->rt6i_flags & RTF_GATEWAY) {
struct neighbour *neigh;
__u8 neigh_flags = 0;
neigh = dst_neigh_lookup(&rt->dst, &rt->rt6i_gateway);
if (neigh) {
neigh_flags = neigh->flags;
neigh_release(neigh);
}
if (!(neigh_flags & NTF_ROUTER)) {
RT6_TRACE("purging route %p via non-router but gateway\n",
rt);
rt6_remove_exception(bucket, rt6_ex);
return;
}
}
gc_args->more++;
}
void rt6_age_exceptions(struct rt6_info *rt,
struct fib6_gc_args *gc_args,
unsigned long now)
{
struct rt6_exception_bucket *bucket;
struct rt6_exception *rt6_ex;
struct hlist_node *tmp;
int i;
if (!rcu_access_pointer(rt->rt6i_exception_bucket))
return;
spin_lock_bh(&rt6_exception_lock);
bucket = rcu_dereference_protected(rt->rt6i_exception_bucket,
lockdep_is_held(&rt6_exception_lock));
if (bucket) {
for (i = 0; i < FIB6_EXCEPTION_BUCKET_SIZE; i++) {
hlist_for_each_entry_safe(rt6_ex, tmp,
&bucket->chain, hlist) {
rt6_age_examine_exception(bucket, rt6_ex,
gc_args, now);
}
bucket++;
}
}
spin_unlock_bh(&rt6_exception_lock);
}
struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table,
int oif, struct flowi6 *fl6, int flags)
{