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author | David S. Miller <davem@sunset.davemloft.net> | 2007-06-10 17:22:39 -0700 |
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committer | David S. Miller <davem@sunset.davemloft.net> | 2007-07-10 22:05:57 -0700 |
commit | e06e7c615877026544ad7f8b309d1a3706410383 (patch) | |
tree | eb087b49279e6db492039a5d684ca9acb13265a3 /net/ipv4/multipath_wrandom.c | |
parent | 4eb6bf6bfb580afaf1e1a1d30cba17a078530cf4 (diff) | |
download | op-kernel-dev-e06e7c615877026544ad7f8b309d1a3706410383.zip op-kernel-dev-e06e7c615877026544ad7f8b309d1a3706410383.tar.gz |
[IPV4]: The scheduled removal of multipath cached routing support.
With help from Chris Wedgwood.
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4/multipath_wrandom.c')
-rw-r--r-- | net/ipv4/multipath_wrandom.c | 329 |
1 files changed, 0 insertions, 329 deletions
diff --git a/net/ipv4/multipath_wrandom.c b/net/ipv4/multipath_wrandom.c deleted file mode 100644 index 57c5036..0000000 --- a/net/ipv4/multipath_wrandom.c +++ /dev/null @@ -1,329 +0,0 @@ -/* - * Weighted random policy for multipath. - * - * - * Version: $Id: multipath_wrandom.c,v 1.1.2.3 2004/09/22 07:51:40 elueck Exp $ - * - * Authors: Einar Lueck <elueck@de.ibm.com><lkml@einar-lueck.de> - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * as published by the Free Software Foundation; either version - * 2 of the License, or (at your option) any later version. - */ - -#include <asm/system.h> -#include <asm/uaccess.h> -#include <linux/types.h> -#include <linux/errno.h> -#include <linux/timer.h> -#include <linux/mm.h> -#include <linux/kernel.h> -#include <linux/fcntl.h> -#include <linux/stat.h> -#include <linux/socket.h> -#include <linux/in.h> -#include <linux/inet.h> -#include <linux/netdevice.h> -#include <linux/inetdevice.h> -#include <linux/igmp.h> -#include <linux/proc_fs.h> -#include <linux/seq_file.h> -#include <linux/module.h> -#include <linux/mroute.h> -#include <linux/init.h> -#include <linux/random.h> -#include <net/ip.h> -#include <net/protocol.h> -#include <linux/skbuff.h> -#include <net/sock.h> -#include <net/icmp.h> -#include <net/udp.h> -#include <net/raw.h> -#include <linux/notifier.h> -#include <linux/if_arp.h> -#include <linux/netfilter_ipv4.h> -#include <net/ipip.h> -#include <net/checksum.h> -#include <net/ip_fib.h> -#include <net/ip_mp_alg.h> - -#define MULTIPATH_STATE_SIZE 15 - -struct multipath_candidate { - struct multipath_candidate *next; - int power; - struct rtable *rt; -}; - -struct multipath_dest { - struct list_head list; - - const struct fib_nh *nh_info; - __be32 netmask; - __be32 network; - unsigned char prefixlen; - - struct rcu_head rcu; -}; - -struct multipath_bucket { - struct list_head head; - spinlock_t lock; -}; - -struct multipath_route { - struct list_head list; - - int oif; - __be32 gw; - struct list_head dests; - - struct rcu_head rcu; -}; - -/* state: primarily weight per route information */ -static struct multipath_bucket state[MULTIPATH_STATE_SIZE]; - -static unsigned char __multipath_lookup_weight(const struct flowi *fl, - const struct rtable *rt) -{ - const int state_idx = rt->idev->dev->ifindex % MULTIPATH_STATE_SIZE; - struct multipath_route *r; - struct multipath_route *target_route = NULL; - struct multipath_dest *d; - int weight = 1; - - /* lookup the weight information for a certain route */ - rcu_read_lock(); - - /* find state entry for gateway or add one if necessary */ - list_for_each_entry_rcu(r, &state[state_idx].head, list) { - if (r->gw == rt->rt_gateway && - r->oif == rt->idev->dev->ifindex) { - target_route = r; - break; - } - } - - if (!target_route) { - /* this should not happen... but we are prepared */ - printk( KERN_CRIT"%s: missing state for gateway: %u and " \ - "device %d\n", __FUNCTION__, rt->rt_gateway, - rt->idev->dev->ifindex); - goto out; - } - - /* find state entry for destination */ - list_for_each_entry_rcu(d, &target_route->dests, list) { - __be32 targetnetwork = fl->fl4_dst & - inet_make_mask(d->prefixlen); - - if ((targetnetwork & d->netmask) == d->network) { - weight = d->nh_info->nh_weight; - goto out; - } - } - -out: - rcu_read_unlock(); - return weight; -} - -static void wrandom_init_state(void) -{ - int i; - - for (i = 0; i < MULTIPATH_STATE_SIZE; ++i) { - INIT_LIST_HEAD(&state[i].head); - spin_lock_init(&state[i].lock); - } -} - -static void wrandom_select_route(const struct flowi *flp, - struct rtable *first, - struct rtable **rp) -{ - struct rtable *rt; - struct rtable *decision; - struct multipath_candidate *first_mpc = NULL; - struct multipath_candidate *mpc, *last_mpc = NULL; - int power = 0; - int last_power; - int selector; - const size_t size_mpc = sizeof(struct multipath_candidate); - - /* collect all candidates and identify their weights */ - for (rt = rcu_dereference(first); rt; - rt = rcu_dereference(rt->u.dst.rt_next)) { - if ((rt->u.dst.flags & DST_BALANCED) != 0 && - multipath_comparekeys(&rt->fl, flp)) { - struct multipath_candidate* mpc = - (struct multipath_candidate*) - kmalloc(size_mpc, GFP_ATOMIC); - - if (!mpc) - return; - - power += __multipath_lookup_weight(flp, rt) * 10000; - - mpc->power = power; - mpc->rt = rt; - mpc->next = NULL; - - if (!first_mpc) - first_mpc = mpc; - else - last_mpc->next = mpc; - - last_mpc = mpc; - } - } - - /* choose a weighted random candidate */ - decision = first; - selector = random32() % power; - last_power = 0; - - /* select candidate, adjust GC data and cleanup local state */ - decision = first; - last_mpc = NULL; - for (mpc = first_mpc; mpc; mpc = mpc->next) { - mpc->rt->u.dst.lastuse = jiffies; - if (last_power <= selector && selector < mpc->power) - decision = mpc->rt; - - last_power = mpc->power; - kfree(last_mpc); - last_mpc = mpc; - } - - /* concurrent __multipath_flush may lead to !last_mpc */ - kfree(last_mpc); - - decision->u.dst.__use++; - *rp = decision; -} - -static void wrandom_set_nhinfo(__be32 network, - __be32 netmask, - unsigned char prefixlen, - const struct fib_nh *nh) -{ - const int state_idx = nh->nh_oif % MULTIPATH_STATE_SIZE; - struct multipath_route *r, *target_route = NULL; - struct multipath_dest *d, *target_dest = NULL; - - /* store the weight information for a certain route */ - spin_lock_bh(&state[state_idx].lock); - - /* find state entry for gateway or add one if necessary */ - list_for_each_entry_rcu(r, &state[state_idx].head, list) { - if (r->gw == nh->nh_gw && r->oif == nh->nh_oif) { - target_route = r; - break; - } - } - - if (!target_route) { - const size_t size_rt = sizeof(struct multipath_route); - target_route = (struct multipath_route *) - kmalloc(size_rt, GFP_ATOMIC); - - target_route->gw = nh->nh_gw; - target_route->oif = nh->nh_oif; - memset(&target_route->rcu, 0, sizeof(struct rcu_head)); - INIT_LIST_HEAD(&target_route->dests); - - list_add_rcu(&target_route->list, &state[state_idx].head); - } - - /* find state entry for destination or add one if necessary */ - list_for_each_entry_rcu(d, &target_route->dests, list) { - if (d->nh_info == nh) { - target_dest = d; - break; - } - } - - if (!target_dest) { - const size_t size_dst = sizeof(struct multipath_dest); - target_dest = (struct multipath_dest*) - kmalloc(size_dst, GFP_ATOMIC); - - target_dest->nh_info = nh; - target_dest->network = network; - target_dest->netmask = netmask; - target_dest->prefixlen = prefixlen; - memset(&target_dest->rcu, 0, sizeof(struct rcu_head)); - - list_add_rcu(&target_dest->list, &target_route->dests); - } - /* else: we already stored this info for another destination => - * we are finished - */ - - spin_unlock_bh(&state[state_idx].lock); -} - -static void __multipath_free(struct rcu_head *head) -{ - struct multipath_route *rt = container_of(head, struct multipath_route, - rcu); - kfree(rt); -} - -static void __multipath_free_dst(struct rcu_head *head) -{ - struct multipath_dest *dst = container_of(head, - struct multipath_dest, - rcu); - kfree(dst); -} - -static void wrandom_flush(void) -{ - int i; - - /* defere delete to all entries */ - for (i = 0; i < MULTIPATH_STATE_SIZE; ++i) { - struct multipath_route *r; - - spin_lock_bh(&state[i].lock); - list_for_each_entry_rcu(r, &state[i].head, list) { - struct multipath_dest *d; - list_for_each_entry_rcu(d, &r->dests, list) { - list_del_rcu(&d->list); - call_rcu(&d->rcu, - __multipath_free_dst); - } - list_del_rcu(&r->list); - call_rcu(&r->rcu, - __multipath_free); - } - - spin_unlock_bh(&state[i].lock); - } -} - -static struct ip_mp_alg_ops wrandom_ops = { - .mp_alg_select_route = wrandom_select_route, - .mp_alg_flush = wrandom_flush, - .mp_alg_set_nhinfo = wrandom_set_nhinfo, -}; - -static int __init wrandom_init(void) -{ - wrandom_init_state(); - - return multipath_alg_register(&wrandom_ops, IP_MP_ALG_WRANDOM); -} - -static void __exit wrandom_exit(void) -{ - multipath_alg_unregister(&wrandom_ops, IP_MP_ALG_WRANDOM); -} - -module_init(wrandom_init); -module_exit(wrandom_exit); -MODULE_LICENSE("GPL"); |