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-rw-r--r--net/ipv4/route.c135
1 files changed, 82 insertions, 53 deletions
diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index 80cf633d9f4a..726ea5e8180a 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -54,6 +54,7 @@
* Marc Boucher : routing by fwmark
* Robert Olsson : Added rt_cache statistics
* Arnaldo C. Melo : Convert proc stuff to seq_file
+ * Eric Dumazet : hashed spinlocks and rt_check_expire() fixes.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
@@ -70,6 +71,7 @@
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/mm.h>
+#include <linux/bootmem.h>
#include <linux/string.h>
#include <linux/socket.h>
#include <linux/sockios.h>
@@ -201,8 +203,37 @@ __u8 ip_tos2prio[16] = {
struct rt_hash_bucket {
struct rtable *chain;
- spinlock_t lock;
-} __attribute__((__aligned__(8)));
+};
+#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK)
+/*
+ * Instead of using one spinlock for each rt_hash_bucket, we use a table of spinlocks
+ * The size of this table is a power of two and depends on the number of CPUS.
+ */
+#if NR_CPUS >= 32
+#define RT_HASH_LOCK_SZ 4096
+#elif NR_CPUS >= 16
+#define RT_HASH_LOCK_SZ 2048
+#elif NR_CPUS >= 8
+#define RT_HASH_LOCK_SZ 1024
+#elif NR_CPUS >= 4
+#define RT_HASH_LOCK_SZ 512
+#else
+#define RT_HASH_LOCK_SZ 256
+#endif
+
+static spinlock_t *rt_hash_locks;
+# define rt_hash_lock_addr(slot) &rt_hash_locks[(slot) & (RT_HASH_LOCK_SZ - 1)]
+# define rt_hash_lock_init() { \
+ int i; \
+ rt_hash_locks = kmalloc(sizeof(spinlock_t) * RT_HASH_LOCK_SZ, GFP_KERNEL); \
+ if (!rt_hash_locks) panic("IP: failed to allocate rt_hash_locks\n"); \
+ for (i = 0; i < RT_HASH_LOCK_SZ; i++) \
+ spin_lock_init(&rt_hash_locks[i]); \
+ }
+#else
+# define rt_hash_lock_addr(slot) NULL
+# define rt_hash_lock_init()
+#endif
static struct rt_hash_bucket *rt_hash_table;
static unsigned rt_hash_mask;
@@ -575,19 +606,26 @@ static struct rtable **rt_remove_balanced_route(struct rtable **chain_head,
/* This runs via a timer and thus is always in BH context. */
static void rt_check_expire(unsigned long dummy)
{
- static int rover;
- int i = rover, t;
+ static unsigned int rover;
+ unsigned int i = rover, goal;
struct rtable *rth, **rthp;
unsigned long now = jiffies;
-
- for (t = ip_rt_gc_interval << rt_hash_log; t >= 0;
- t -= ip_rt_gc_timeout) {
+ u64 mult;
+
+ mult = ((u64)ip_rt_gc_interval) << rt_hash_log;
+ if (ip_rt_gc_timeout > 1)
+ do_div(mult, ip_rt_gc_timeout);
+ goal = (unsigned int)mult;
+ if (goal > rt_hash_mask) goal = rt_hash_mask + 1;
+ for (; goal > 0; goal--) {
unsigned long tmo = ip_rt_gc_timeout;
i = (i + 1) & rt_hash_mask;
rthp = &rt_hash_table[i].chain;
- spin_lock(&rt_hash_table[i].lock);
+ if (*rthp == 0)
+ continue;
+ spin_lock(rt_hash_lock_addr(i));
while ((rth = *rthp) != NULL) {
if (rth->u.dst.expires) {
/* Entry is expired even if it is in use */
@@ -620,14 +658,14 @@ static void rt_check_expire(unsigned long dummy)
rt_free(rth);
#endif /* CONFIG_IP_ROUTE_MULTIPATH_CACHED */
}
- spin_unlock(&rt_hash_table[i].lock);
+ spin_unlock(rt_hash_lock_addr(i));
/* Fallback loop breaker. */
if (time_after(jiffies, now))
break;
}
rover = i;
- mod_timer(&rt_periodic_timer, now + ip_rt_gc_interval);
+ mod_timer(&rt_periodic_timer, jiffies + ip_rt_gc_interval);
}
/* This can run from both BH and non-BH contexts, the latter
@@ -643,11 +681,11 @@ static void rt_run_flush(unsigned long dummy)
get_random_bytes(&rt_hash_rnd, 4);
for (i = rt_hash_mask; i >= 0; i--) {
- spin_lock_bh(&rt_hash_table[i].lock);
+ spin_lock_bh(rt_hash_lock_addr(i));
rth = rt_hash_table[i].chain;
if (rth)
rt_hash_table[i].chain = NULL;
- spin_unlock_bh(&rt_hash_table[i].lock);
+ spin_unlock_bh(rt_hash_lock_addr(i));
for (; rth; rth = next) {
next = rth->u.rt_next;
@@ -780,7 +818,7 @@ static int rt_garbage_collect(void)
k = (k + 1) & rt_hash_mask;
rthp = &rt_hash_table[k].chain;
- spin_lock_bh(&rt_hash_table[k].lock);
+ spin_lock_bh(rt_hash_lock_addr(k));
while ((rth = *rthp) != NULL) {
if (!rt_may_expire(rth, tmo, expire)) {
tmo >>= 1;
@@ -812,7 +850,7 @@ static int rt_garbage_collect(void)
goal--;
#endif /* CONFIG_IP_ROUTE_MULTIPATH_CACHED */
}
- spin_unlock_bh(&rt_hash_table[k].lock);
+ spin_unlock_bh(rt_hash_lock_addr(k));
if (goal <= 0)
break;
}
@@ -882,7 +920,7 @@ restart:
rthp = &rt_hash_table[hash].chain;
- spin_lock_bh(&rt_hash_table[hash].lock);
+ spin_lock_bh(rt_hash_lock_addr(hash));
while ((rth = *rthp) != NULL) {
#ifdef CONFIG_IP_ROUTE_MULTIPATH_CACHED
if (!(rth->u.dst.flags & DST_BALANCED) &&
@@ -908,7 +946,7 @@ restart:
rth->u.dst.__use++;
dst_hold(&rth->u.dst);
rth->u.dst.lastuse = now;
- spin_unlock_bh(&rt_hash_table[hash].lock);
+ spin_unlock_bh(rt_hash_lock_addr(hash));
rt_drop(rt);
*rp = rth;
@@ -949,7 +987,7 @@ restart:
if (rt->rt_type == RTN_UNICAST || rt->fl.iif == 0) {
int err = arp_bind_neighbour(&rt->u.dst);
if (err) {
- spin_unlock_bh(&rt_hash_table[hash].lock);
+ spin_unlock_bh(rt_hash_lock_addr(hash));
if (err != -ENOBUFS) {
rt_drop(rt);
@@ -990,7 +1028,7 @@ restart:
}
#endif
rt_hash_table[hash].chain = rt;
- spin_unlock_bh(&rt_hash_table[hash].lock);
+ spin_unlock_bh(rt_hash_lock_addr(hash));
*rp = rt;
return 0;
}
@@ -1058,7 +1096,7 @@ static void rt_del(unsigned hash, struct rtable *rt)
{
struct rtable **rthp;
- spin_lock_bh(&rt_hash_table[hash].lock);
+ spin_lock_bh(rt_hash_lock_addr(hash));
ip_rt_put(rt);
for (rthp = &rt_hash_table[hash].chain; *rthp;
rthp = &(*rthp)->u.rt_next)
@@ -1067,7 +1105,7 @@ static void rt_del(unsigned hash, struct rtable *rt)
rt_free(rt);
break;
}
- spin_unlock_bh(&rt_hash_table[hash].lock);
+ spin_unlock_bh(rt_hash_lock_addr(hash));
}
void ip_rt_redirect(u32 old_gw, u32 daddr, u32 new_gw,
@@ -1909,7 +1947,7 @@ static int ip_route_input_slow(struct sk_buff *skb, u32 daddr, u32 saddr,
*/
if ((err = fib_lookup(&fl, &res)) != 0) {
if (!IN_DEV_FORWARD(in_dev))
- goto e_inval;
+ goto e_hostunreach;
goto no_route;
}
free_res = 1;
@@ -1933,7 +1971,7 @@ static int ip_route_input_slow(struct sk_buff *skb, u32 daddr, u32 saddr,
}
if (!IN_DEV_FORWARD(in_dev))
- goto e_inval;
+ goto e_hostunreach;
if (res.type != RTN_UNICAST)
goto martian_destination;
@@ -2025,6 +2063,11 @@ martian_destination:
"%u.%u.%u.%u, dev %s\n",
NIPQUAD(daddr), NIPQUAD(saddr), dev->name);
#endif
+
+e_hostunreach:
+ err = -EHOSTUNREACH;
+ goto done;
+
e_inval:
err = -EINVAL;
goto done;
@@ -3068,12 +3111,14 @@ __setup("rhash_entries=", set_rhash_entries);
int __init ip_rt_init(void)
{
- int i, order, goal, rc = 0;
+ int rc = 0;
rt_hash_rnd = (int) ((num_physpages ^ (num_physpages>>8)) ^
(jiffies ^ (jiffies >> 7)));
#ifdef CONFIG_NET_CLS_ROUTE
+ {
+ int order;
for (order = 0;
(PAGE_SIZE << order) < 256 * sizeof(struct ip_rt_acct) * NR_CPUS; order++)
/* NOTHING */;
@@ -3081,6 +3126,7 @@ int __init ip_rt_init(void)
if (!ip_rt_acct)
panic("IP: failed to allocate ip_rt_acct\n");
memset(ip_rt_acct, 0, PAGE_SIZE << order);
+ }
#endif
ipv4_dst_ops.kmem_cachep = kmem_cache_create("ip_dst_cache",
@@ -3091,36 +3137,19 @@ int __init ip_rt_init(void)
if (!ipv4_dst_ops.kmem_cachep)
panic("IP: failed to allocate ip_dst_cache\n");
- goal = num_physpages >> (26 - PAGE_SHIFT);
- if (rhash_entries)
- goal = (rhash_entries * sizeof(struct rt_hash_bucket)) >> PAGE_SHIFT;
- for (order = 0; (1UL << order) < goal; order++)
- /* NOTHING */;
-
- do {
- rt_hash_mask = (1UL << order) * PAGE_SIZE /
- sizeof(struct rt_hash_bucket);
- while (rt_hash_mask & (rt_hash_mask - 1))
- rt_hash_mask--;
- rt_hash_table = (struct rt_hash_bucket *)
- __get_free_pages(GFP_ATOMIC, order);
- } while (rt_hash_table == NULL && --order > 0);
-
- if (!rt_hash_table)
- panic("Failed to allocate IP route cache hash table\n");
-
- printk(KERN_INFO "IP: routing cache hash table of %u buckets, %ldKbytes\n",
- rt_hash_mask,
- (long) (rt_hash_mask * sizeof(struct rt_hash_bucket)) / 1024);
-
- for (rt_hash_log = 0; (1 << rt_hash_log) != rt_hash_mask; rt_hash_log++)
- /* NOTHING */;
-
- rt_hash_mask--;
- for (i = 0; i <= rt_hash_mask; i++) {
- spin_lock_init(&rt_hash_table[i].lock);
- rt_hash_table[i].chain = NULL;
- }
+ rt_hash_table = (struct rt_hash_bucket *)
+ alloc_large_system_hash("IP route cache",
+ sizeof(struct rt_hash_bucket),
+ rhash_entries,
+ (num_physpages >= 128 * 1024) ?
+ (27 - PAGE_SHIFT) :
+ (29 - PAGE_SHIFT),
+ HASH_HIGHMEM,
+ &rt_hash_log,
+ &rt_hash_mask,
+ 0);
+ memset(rt_hash_table, 0, (rt_hash_mask + 1) * sizeof(struct rt_hash_bucket));
+ rt_hash_lock_init();
ipv4_dst_ops.gc_thresh = (rt_hash_mask + 1);
ip_rt_max_size = (rt_hash_mask + 1) * 16;
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-01 03:26:09 +0000