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-rw-r--r--net/ipv4/route.c105
1 files changed, 70 insertions, 35 deletions
diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index b2ba5581d2ae..cb562fdd9b9a 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -90,6 +90,7 @@
#include <linux/jhash.h>
#include <linux/rcupdate.h>
#include <linux/times.h>
+#include <linux/slab.h>
#include <net/dst.h>
#include <net/net_namespace.h>
#include <net/protocol.h>
@@ -146,7 +147,6 @@ static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst);
static void ipv4_link_failure(struct sk_buff *skb);
static void ip_rt_update_pmtu(struct dst_entry *dst, u32 mtu);
static int rt_garbage_collect(struct dst_ops *ops);
-static void rt_emergency_hash_rebuild(struct net *net);
static struct dst_ops ipv4_dst_ops = {
@@ -780,11 +780,30 @@ static void rt_do_flush(int process_context)
#define FRACT_BITS 3
#define ONE (1UL << FRACT_BITS)
+/*
+ * Given a hash chain and an item in this hash chain,
+ * find if a previous entry has the same hash_inputs
+ * (but differs on tos, mark or oif)
+ * Returns 0 if an alias is found.
+ * Returns ONE if rth has no alias before itself.
+ */
+static int has_noalias(const struct rtable *head, const struct rtable *rth)
+{
+ const struct rtable *aux = head;
+
+ while (aux != rth) {
+ if (compare_hash_inputs(&aux->fl, &rth->fl))
+ return 0;
+ aux = aux->u.dst.rt_next;
+ }
+ return ONE;
+}
+
static void rt_check_expire(void)
{
static unsigned int rover;
unsigned int i = rover, goal;
- struct rtable *rth, *aux, **rthp;
+ struct rtable *rth, **rthp;
unsigned long samples = 0;
unsigned long sum = 0, sum2 = 0;
unsigned long delta;
@@ -835,15 +854,7 @@ nofree:
* attributes don't unfairly skew
* the length computation
*/
- for (aux = rt_hash_table[i].chain;;) {
- if (aux == rth) {
- length += ONE;
- break;
- }
- if (compare_hash_inputs(&aux->fl, &rth->fl))
- break;
- aux = aux->u.dst.rt_next;
- }
+ length += has_noalias(rt_hash_table[i].chain, rth);
continue;
}
} else if (!rt_may_expire(rth, tmo, ip_rt_gc_timeout))
@@ -922,10 +933,8 @@ static void rt_secret_rebuild_oneshot(struct net *net)
{
del_timer_sync(&net->ipv4.rt_secret_timer);
rt_cache_invalidate(net);
- if (ip_rt_secret_interval) {
- net->ipv4.rt_secret_timer.expires += ip_rt_secret_interval;
- add_timer(&net->ipv4.rt_secret_timer);
- }
+ if (ip_rt_secret_interval)
+ mod_timer(&net->ipv4.rt_secret_timer, jiffies + ip_rt_secret_interval);
}
static void rt_emergency_hash_rebuild(struct net *net)
@@ -1073,8 +1082,23 @@ work_done:
out: return 0;
}
+/*
+ * Returns number of entries in a hash chain that have different hash_inputs
+ */
+static int slow_chain_length(const struct rtable *head)
+{
+ int length = 0;
+ const struct rtable *rth = head;
+
+ while (rth) {
+ length += has_noalias(head, rth);
+ rth = rth->u.dst.rt_next;
+ }
+ return length >> FRACT_BITS;
+}
+
static int rt_intern_hash(unsigned hash, struct rtable *rt,
- struct rtable **rp, struct sk_buff *skb)
+ struct rtable **rp, struct sk_buff *skb, int ifindex)
{
struct rtable *rth, **rthp;
unsigned long now;
@@ -1185,14 +1209,20 @@ restart:
rt_free(cand);
}
} else {
- if (chain_length > rt_chain_length_max) {
+ if (chain_length > rt_chain_length_max &&
+ slow_chain_length(rt_hash_table[hash].chain) > rt_chain_length_max) {
struct net *net = dev_net(rt->u.dst.dev);
int num = ++net->ipv4.current_rt_cache_rebuild_count;
- if (!rt_caching(dev_net(rt->u.dst.dev))) {
+ if (!rt_caching(net)) {
printk(KERN_WARNING "%s: %d rebuilds is over limit, route caching disabled\n",
rt->u.dst.dev->name, num);
}
- rt_emergency_hash_rebuild(dev_net(rt->u.dst.dev));
+ rt_emergency_hash_rebuild(net);
+ spin_unlock_bh(rt_hash_lock_addr(hash));
+
+ hash = rt_hash(rt->fl.fl4_dst, rt->fl.fl4_src,
+ ifindex, rt_genid(net));
+ goto restart;
}
}
@@ -1417,7 +1447,7 @@ void ip_rt_redirect(__be32 old_gw, __be32 daddr, __be32 new_gw,
dev_hold(rt->u.dst.dev);
if (rt->idev)
in_dev_hold(rt->idev);
- rt->u.dst.obsolete = 0;
+ rt->u.dst.obsolete = -1;
rt->u.dst.lastuse = jiffies;
rt->u.dst.path = &rt->u.dst;
rt->u.dst.neighbour = NULL;
@@ -1453,7 +1483,7 @@ void ip_rt_redirect(__be32 old_gw, __be32 daddr, __be32 new_gw,
&netevent);
rt_del(hash, rth);
- if (!rt_intern_hash(hash, rt, &rt, NULL))
+ if (!rt_intern_hash(hash, rt, &rt, NULL, rt->fl.oif))
ip_rt_put(rt);
goto do_next;
}
@@ -1482,11 +1512,12 @@ static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst)
struct dst_entry *ret = dst;
if (rt) {
- if (dst->obsolete) {
+ if (dst->obsolete > 0) {
ip_rt_put(rt);
ret = NULL;
} else if ((rt->rt_flags & RTCF_REDIRECTED) ||
- rt->u.dst.expires) {
+ (rt->u.dst.expires &&
+ time_after_eq(jiffies, rt->u.dst.expires))) {
unsigned hash = rt_hash(rt->fl.fl4_dst, rt->fl.fl4_src,
rt->fl.oif,
rt_genid(dev_net(dst->dev)));
@@ -1702,7 +1733,9 @@ static void ip_rt_update_pmtu(struct dst_entry *dst, u32 mtu)
static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie)
{
- return NULL;
+ if (rt_is_expired((struct rtable *)dst))
+ return NULL;
+ return dst;
}
static void ipv4_dst_destroy(struct dst_entry *dst)
@@ -1864,7 +1897,8 @@ static int ip_route_input_mc(struct sk_buff *skb, __be32 daddr, __be32 saddr,
if (!rth)
goto e_nobufs;
- rth->u.dst.output= ip_rt_bug;
+ rth->u.dst.output = ip_rt_bug;
+ rth->u.dst.obsolete = -1;
atomic_set(&rth->u.dst.__refcnt, 1);
rth->u.dst.flags= DST_HOST;
@@ -1903,7 +1937,7 @@ static int ip_route_input_mc(struct sk_buff *skb, __be32 daddr, __be32 saddr,
in_dev_put(in_dev);
hash = rt_hash(daddr, saddr, dev->ifindex, rt_genid(dev_net(dev)));
- return rt_intern_hash(hash, rth, NULL, skb);
+ return rt_intern_hash(hash, rth, NULL, skb, dev->ifindex);
e_nobufs:
in_dev_put(in_dev);
@@ -2030,6 +2064,7 @@ static int __mkroute_input(struct sk_buff *skb,
rth->fl.oif = 0;
rth->rt_spec_dst= spec_dst;
+ rth->u.dst.obsolete = -1;
rth->u.dst.input = ip_forward;
rth->u.dst.output = ip_output;
rth->rt_genid = rt_genid(dev_net(rth->u.dst.dev));
@@ -2069,7 +2104,7 @@ static int ip_mkroute_input(struct sk_buff *skb,
/* put it into the cache */
hash = rt_hash(daddr, saddr, fl->iif,
rt_genid(dev_net(rth->u.dst.dev)));
- return rt_intern_hash(hash, rth, NULL, skb);
+ return rt_intern_hash(hash, rth, NULL, skb, fl->iif);
}
/*
@@ -2194,6 +2229,7 @@ local_input:
goto e_nobufs;
rth->u.dst.output= ip_rt_bug;
+ rth->u.dst.obsolete = -1;
rth->rt_genid = rt_genid(net);
atomic_set(&rth->u.dst.__refcnt, 1);
@@ -2225,7 +2261,7 @@ local_input:
}
rth->rt_type = res.type;
hash = rt_hash(daddr, saddr, fl.iif, rt_genid(net));
- err = rt_intern_hash(hash, rth, NULL, skb);
+ err = rt_intern_hash(hash, rth, NULL, skb, fl.iif);
goto done;
no_route:
@@ -2420,6 +2456,7 @@ static int __mkroute_output(struct rtable **result,
rth->rt_spec_dst= fl->fl4_src;
rth->u.dst.output=ip_output;
+ rth->u.dst.obsolete = -1;
rth->rt_genid = rt_genid(dev_net(dev_out));
RT_CACHE_STAT_INC(out_slow_tot);
@@ -2471,7 +2508,7 @@ static int ip_mkroute_output(struct rtable **rp,
if (err == 0) {
hash = rt_hash(oldflp->fl4_dst, oldflp->fl4_src, oldflp->oif,
rt_genid(dev_net(dev_out)));
- err = rt_intern_hash(hash, rth, rp, NULL);
+ err = rt_intern_hash(hash, rth, rp, NULL, oldflp->oif);
}
return err;
@@ -3077,22 +3114,20 @@ static void rt_secret_reschedule(int old)
rtnl_lock();
for_each_net(net) {
int deleted = del_timer_sync(&net->ipv4.rt_secret_timer);
+ long time;
if (!new)
continue;
if (deleted) {
- long time = net->ipv4.rt_secret_timer.expires - jiffies;
+ time = net->ipv4.rt_secret_timer.expires - jiffies;
if (time <= 0 || (time += diff) <= 0)
time = 0;
-
- net->ipv4.rt_secret_timer.expires = time;
} else
- net->ipv4.rt_secret_timer.expires = new;
+ time = new;
- net->ipv4.rt_secret_timer.expires += jiffies;
- add_timer(&net->ipv4.rt_secret_timer);
+ mod_timer(&net->ipv4.rt_secret_timer, jiffies + time);
}
rtnl_unlock();
}
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-20 17:17:57 +0000