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![Simon Horman](/assets/img/avatar_default.png)
Acked-by: Graeme Fowler <graeme@graemef.net> Signed-off-by: Simon Horman <horms@verge.net.au> Signed-off-by: David S. Miller <davem@davemloft.net>
765 lines
19 KiB
C
765 lines
19 KiB
C
/*
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* IPVS: Locality-Based Least-Connection with Replication scheduler
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*
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* Authors: Wensong Zhang <wensong@gnuchina.org>
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*
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* Changes:
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* Julian Anastasov : Added the missing (dest->weight>0)
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* condition in the ip_vs_dest_set_max.
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*
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*/
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/*
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* The lblc/r algorithm is as follows (pseudo code):
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*
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* if serverSet[dest_ip] is null then
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* n, serverSet[dest_ip] <- {weighted least-conn node};
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* else
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* n <- {least-conn (alive) node in serverSet[dest_ip]};
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* if (n is null) OR
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* (n.conns>n.weight AND
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* there is a node m with m.conns<m.weight/2) then
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* n <- {weighted least-conn node};
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* add n to serverSet[dest_ip];
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* if |serverSet[dest_ip]| > 1 AND
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* now - serverSet[dest_ip].lastMod > T then
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* m <- {most conn node in serverSet[dest_ip]};
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* remove m from serverSet[dest_ip];
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* if serverSet[dest_ip] changed then
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* serverSet[dest_ip].lastMod <- now;
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*
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* return n;
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*
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*/
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#include <linux/ip.h>
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#include <linux/module.h>
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#include <linux/kernel.h>
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#include <linux/skbuff.h>
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#include <linux/jiffies.h>
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/* for sysctl */
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#include <linux/fs.h>
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#include <linux/sysctl.h>
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#include <net/net_namespace.h>
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#include <net/ip_vs.h>
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/*
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* It is for garbage collection of stale IPVS lblcr entries,
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* when the table is full.
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*/
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#define CHECK_EXPIRE_INTERVAL (60*HZ)
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#define ENTRY_TIMEOUT (6*60*HZ)
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/*
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* It is for full expiration check.
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* When there is no partial expiration check (garbage collection)
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* in a half hour, do a full expiration check to collect stale
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* entries that haven't been touched for a day.
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*/
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#define COUNT_FOR_FULL_EXPIRATION 30
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static int sysctl_ip_vs_lblcr_expiration = 24*60*60*HZ;
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/*
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* for IPVS lblcr entry hash table
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*/
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#ifndef CONFIG_IP_VS_LBLCR_TAB_BITS
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#define CONFIG_IP_VS_LBLCR_TAB_BITS 10
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#endif
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#define IP_VS_LBLCR_TAB_BITS CONFIG_IP_VS_LBLCR_TAB_BITS
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#define IP_VS_LBLCR_TAB_SIZE (1 << IP_VS_LBLCR_TAB_BITS)
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#define IP_VS_LBLCR_TAB_MASK (IP_VS_LBLCR_TAB_SIZE - 1)
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/*
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* IPVS destination set structure and operations
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*/
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struct ip_vs_dest_list {
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struct ip_vs_dest_list *next; /* list link */
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struct ip_vs_dest *dest; /* destination server */
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};
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struct ip_vs_dest_set {
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atomic_t size; /* set size */
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unsigned long lastmod; /* last modified time */
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struct ip_vs_dest_list *list; /* destination list */
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rwlock_t lock; /* lock for this list */
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};
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static struct ip_vs_dest_list *
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ip_vs_dest_set_insert(struct ip_vs_dest_set *set, struct ip_vs_dest *dest)
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{
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struct ip_vs_dest_list *e;
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for (e=set->list; e!=NULL; e=e->next) {
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if (e->dest == dest)
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/* already existed */
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return NULL;
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}
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e = kmalloc(sizeof(*e), GFP_ATOMIC);
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if (e == NULL) {
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IP_VS_ERR("ip_vs_dest_set_insert(): no memory\n");
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return NULL;
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}
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atomic_inc(&dest->refcnt);
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e->dest = dest;
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/* link it to the list */
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e->next = set->list;
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set->list = e;
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atomic_inc(&set->size);
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set->lastmod = jiffies;
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return e;
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}
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static void
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ip_vs_dest_set_erase(struct ip_vs_dest_set *set, struct ip_vs_dest *dest)
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{
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struct ip_vs_dest_list *e, **ep;
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for (ep=&set->list, e=*ep; e!=NULL; e=*ep) {
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if (e->dest == dest) {
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/* HIT */
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*ep = e->next;
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atomic_dec(&set->size);
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set->lastmod = jiffies;
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atomic_dec(&e->dest->refcnt);
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kfree(e);
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break;
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}
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ep = &e->next;
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}
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}
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static void ip_vs_dest_set_eraseall(struct ip_vs_dest_set *set)
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{
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struct ip_vs_dest_list *e, **ep;
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write_lock(&set->lock);
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for (ep=&set->list, e=*ep; e!=NULL; e=*ep) {
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*ep = e->next;
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/*
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* We don't kfree dest because it is refered either
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* by its service or by the trash dest list.
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*/
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atomic_dec(&e->dest->refcnt);
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kfree(e);
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}
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write_unlock(&set->lock);
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}
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/* get weighted least-connection node in the destination set */
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static inline struct ip_vs_dest *ip_vs_dest_set_min(struct ip_vs_dest_set *set)
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{
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register struct ip_vs_dest_list *e;
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struct ip_vs_dest *dest, *least;
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int loh, doh;
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if (set == NULL)
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return NULL;
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/* select the first destination server, whose weight > 0 */
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for (e=set->list; e!=NULL; e=e->next) {
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least = e->dest;
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if (least->flags & IP_VS_DEST_F_OVERLOAD)
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continue;
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if ((atomic_read(&least->weight) > 0)
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&& (least->flags & IP_VS_DEST_F_AVAILABLE)) {
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loh = atomic_read(&least->activeconns) * 50
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+ atomic_read(&least->inactconns);
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goto nextstage;
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}
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}
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return NULL;
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/* find the destination with the weighted least load */
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nextstage:
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for (e=e->next; e!=NULL; e=e->next) {
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dest = e->dest;
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if (dest->flags & IP_VS_DEST_F_OVERLOAD)
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continue;
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doh = atomic_read(&dest->activeconns) * 50
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+ atomic_read(&dest->inactconns);
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if ((loh * atomic_read(&dest->weight) >
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doh * atomic_read(&least->weight))
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&& (dest->flags & IP_VS_DEST_F_AVAILABLE)) {
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least = dest;
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loh = doh;
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}
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}
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IP_VS_DBG_BUF(6, "ip_vs_dest_set_min: server %s:%d "
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"activeconns %d refcnt %d weight %d overhead %d\n",
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IP_VS_DBG_ADDR(least->af, &least->addr),
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ntohs(least->port),
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atomic_read(&least->activeconns),
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atomic_read(&least->refcnt),
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atomic_read(&least->weight), loh);
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return least;
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}
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/* get weighted most-connection node in the destination set */
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static inline struct ip_vs_dest *ip_vs_dest_set_max(struct ip_vs_dest_set *set)
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{
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register struct ip_vs_dest_list *e;
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struct ip_vs_dest *dest, *most;
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int moh, doh;
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if (set == NULL)
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return NULL;
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/* select the first destination server, whose weight > 0 */
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for (e=set->list; e!=NULL; e=e->next) {
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most = e->dest;
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if (atomic_read(&most->weight) > 0) {
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moh = atomic_read(&most->activeconns) * 50
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+ atomic_read(&most->inactconns);
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goto nextstage;
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}
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}
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return NULL;
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/* find the destination with the weighted most load */
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nextstage:
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for (e=e->next; e!=NULL; e=e->next) {
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dest = e->dest;
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doh = atomic_read(&dest->activeconns) * 50
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+ atomic_read(&dest->inactconns);
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/* moh/mw < doh/dw ==> moh*dw < doh*mw, where mw,dw>0 */
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if ((moh * atomic_read(&dest->weight) <
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doh * atomic_read(&most->weight))
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&& (atomic_read(&dest->weight) > 0)) {
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most = dest;
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moh = doh;
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}
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}
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IP_VS_DBG_BUF(6, "ip_vs_dest_set_max: server %s:%d "
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"activeconns %d refcnt %d weight %d overhead %d\n",
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IP_VS_DBG_ADDR(most->af, &most->addr), ntohs(most->port),
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atomic_read(&most->activeconns),
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atomic_read(&most->refcnt),
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atomic_read(&most->weight), moh);
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return most;
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}
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/*
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* IPVS lblcr entry represents an association between destination
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* IP address and its destination server set
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*/
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struct ip_vs_lblcr_entry {
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struct list_head list;
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int af; /* address family */
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union nf_inet_addr addr; /* destination IP address */
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struct ip_vs_dest_set set; /* destination server set */
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unsigned long lastuse; /* last used time */
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};
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/*
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* IPVS lblcr hash table
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*/
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struct ip_vs_lblcr_table {
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struct list_head bucket[IP_VS_LBLCR_TAB_SIZE]; /* hash bucket */
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atomic_t entries; /* number of entries */
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int max_size; /* maximum size of entries */
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struct timer_list periodic_timer; /* collect stale entries */
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int rover; /* rover for expire check */
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int counter; /* counter for no expire */
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};
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/*
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* IPVS LBLCR sysctl table
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*/
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static ctl_table vs_vars_table[] = {
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{
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.procname = "lblcr_expiration",
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.data = &sysctl_ip_vs_lblcr_expiration,
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.maxlen = sizeof(int),
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.mode = 0644,
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.proc_handler = proc_dointvec_jiffies,
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},
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{ .ctl_name = 0 }
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};
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static struct ctl_table_header * sysctl_header;
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static inline void ip_vs_lblcr_free(struct ip_vs_lblcr_entry *en)
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{
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list_del(&en->list);
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ip_vs_dest_set_eraseall(&en->set);
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kfree(en);
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}
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/*
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* Returns hash value for IPVS LBLCR entry
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*/
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static inline unsigned
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ip_vs_lblcr_hashkey(int af, const union nf_inet_addr *addr)
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{
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__be32 addr_fold = addr->ip;
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#ifdef CONFIG_IP_VS_IPV6
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if (af == AF_INET6)
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addr_fold = addr->ip6[0]^addr->ip6[1]^
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addr->ip6[2]^addr->ip6[3];
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#endif
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return (ntohl(addr_fold)*2654435761UL) & IP_VS_LBLCR_TAB_MASK;
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}
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/*
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* Hash an entry in the ip_vs_lblcr_table.
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* returns bool success.
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*/
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static void
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ip_vs_lblcr_hash(struct ip_vs_lblcr_table *tbl, struct ip_vs_lblcr_entry *en)
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{
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unsigned hash = ip_vs_lblcr_hashkey(en->af, &en->addr);
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list_add(&en->list, &tbl->bucket[hash]);
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atomic_inc(&tbl->entries);
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}
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/*
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* Get ip_vs_lblcr_entry associated with supplied parameters. Called under
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* read lock.
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*/
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static inline struct ip_vs_lblcr_entry *
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ip_vs_lblcr_get(int af, struct ip_vs_lblcr_table *tbl,
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const union nf_inet_addr *addr)
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{
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unsigned hash = ip_vs_lblcr_hashkey(af, addr);
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struct ip_vs_lblcr_entry *en;
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list_for_each_entry(en, &tbl->bucket[hash], list)
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if (ip_vs_addr_equal(af, &en->addr, addr))
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return en;
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return NULL;
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}
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/*
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* Create or update an ip_vs_lblcr_entry, which is a mapping of a destination
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* IP address to a server. Called under write lock.
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*/
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static inline struct ip_vs_lblcr_entry *
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ip_vs_lblcr_new(struct ip_vs_lblcr_table *tbl, const union nf_inet_addr *daddr,
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struct ip_vs_dest *dest)
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{
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struct ip_vs_lblcr_entry *en;
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en = ip_vs_lblcr_get(dest->af, tbl, daddr);
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if (!en) {
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en = kmalloc(sizeof(*en), GFP_ATOMIC);
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if (!en) {
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IP_VS_ERR("ip_vs_lblcr_new(): no memory\n");
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return NULL;
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}
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en->af = dest->af;
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ip_vs_addr_copy(dest->af, &en->addr, daddr);
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en->lastuse = jiffies;
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/* initilize its dest set */
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atomic_set(&(en->set.size), 0);
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en->set.list = NULL;
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rwlock_init(&en->set.lock);
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ip_vs_lblcr_hash(tbl, en);
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}
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write_lock(&en->set.lock);
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ip_vs_dest_set_insert(&en->set, dest);
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write_unlock(&en->set.lock);
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return en;
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}
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/*
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* Flush all the entries of the specified table.
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*/
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static void ip_vs_lblcr_flush(struct ip_vs_lblcr_table *tbl)
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{
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int i;
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struct ip_vs_lblcr_entry *en, *nxt;
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/* No locking required, only called during cleanup. */
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for (i=0; i<IP_VS_LBLCR_TAB_SIZE; i++) {
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list_for_each_entry_safe(en, nxt, &tbl->bucket[i], list) {
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ip_vs_lblcr_free(en);
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}
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}
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}
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static inline void ip_vs_lblcr_full_check(struct ip_vs_service *svc)
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{
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struct ip_vs_lblcr_table *tbl = svc->sched_data;
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unsigned long now = jiffies;
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int i, j;
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struct ip_vs_lblcr_entry *en, *nxt;
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for (i=0, j=tbl->rover; i<IP_VS_LBLCR_TAB_SIZE; i++) {
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j = (j + 1) & IP_VS_LBLCR_TAB_MASK;
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write_lock(&svc->sched_lock);
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list_for_each_entry_safe(en, nxt, &tbl->bucket[j], list) {
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if (time_after(en->lastuse+sysctl_ip_vs_lblcr_expiration,
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now))
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continue;
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ip_vs_lblcr_free(en);
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atomic_dec(&tbl->entries);
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}
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write_unlock(&svc->sched_lock);
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}
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tbl->rover = j;
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}
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/*
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* Periodical timer handler for IPVS lblcr table
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* It is used to collect stale entries when the number of entries
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* exceeds the maximum size of the table.
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*
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* Fixme: we probably need more complicated algorithm to collect
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* entries that have not been used for a long time even
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* if the number of entries doesn't exceed the maximum size
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* of the table.
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* The full expiration check is for this purpose now.
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*/
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static void ip_vs_lblcr_check_expire(unsigned long data)
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{
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struct ip_vs_service *svc = (struct ip_vs_service *) data;
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struct ip_vs_lblcr_table *tbl = svc->sched_data;
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unsigned long now = jiffies;
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int goal;
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int i, j;
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struct ip_vs_lblcr_entry *en, *nxt;
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if ((tbl->counter % COUNT_FOR_FULL_EXPIRATION) == 0) {
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/* do full expiration check */
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ip_vs_lblcr_full_check(svc);
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tbl->counter = 1;
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goto out;
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}
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if (atomic_read(&tbl->entries) <= tbl->max_size) {
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tbl->counter++;
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goto out;
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}
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goal = (atomic_read(&tbl->entries) - tbl->max_size)*4/3;
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if (goal > tbl->max_size/2)
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goal = tbl->max_size/2;
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for (i=0, j=tbl->rover; i<IP_VS_LBLCR_TAB_SIZE; i++) {
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j = (j + 1) & IP_VS_LBLCR_TAB_MASK;
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write_lock(&svc->sched_lock);
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list_for_each_entry_safe(en, nxt, &tbl->bucket[j], list) {
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if (time_before(now, en->lastuse+ENTRY_TIMEOUT))
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continue;
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ip_vs_lblcr_free(en);
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atomic_dec(&tbl->entries);
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goal--;
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}
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write_unlock(&svc->sched_lock);
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if (goal <= 0)
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break;
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}
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tbl->rover = j;
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out:
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mod_timer(&tbl->periodic_timer, jiffies+CHECK_EXPIRE_INTERVAL);
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}
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static int ip_vs_lblcr_init_svc(struct ip_vs_service *svc)
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{
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int i;
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struct ip_vs_lblcr_table *tbl;
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/*
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* Allocate the ip_vs_lblcr_table for this service
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*/
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tbl = kmalloc(sizeof(*tbl), GFP_ATOMIC);
|
|
if (tbl == NULL) {
|
|
IP_VS_ERR("ip_vs_lblcr_init_svc(): no memory\n");
|
|
return -ENOMEM;
|
|
}
|
|
svc->sched_data = tbl;
|
|
IP_VS_DBG(6, "LBLCR hash table (memory=%Zdbytes) allocated for "
|
|
"current service\n", sizeof(*tbl));
|
|
|
|
/*
|
|
* Initialize the hash buckets
|
|
*/
|
|
for (i=0; i<IP_VS_LBLCR_TAB_SIZE; i++) {
|
|
INIT_LIST_HEAD(&tbl->bucket[i]);
|
|
}
|
|
tbl->max_size = IP_VS_LBLCR_TAB_SIZE*16;
|
|
tbl->rover = 0;
|
|
tbl->counter = 1;
|
|
|
|
/*
|
|
* Hook periodic timer for garbage collection
|
|
*/
|
|
setup_timer(&tbl->periodic_timer, ip_vs_lblcr_check_expire,
|
|
(unsigned long)svc);
|
|
mod_timer(&tbl->periodic_timer, jiffies + CHECK_EXPIRE_INTERVAL);
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
static int ip_vs_lblcr_done_svc(struct ip_vs_service *svc)
|
|
{
|
|
struct ip_vs_lblcr_table *tbl = svc->sched_data;
|
|
|
|
/* remove periodic timer */
|
|
del_timer_sync(&tbl->periodic_timer);
|
|
|
|
/* got to clean up table entries here */
|
|
ip_vs_lblcr_flush(tbl);
|
|
|
|
/* release the table itself */
|
|
kfree(tbl);
|
|
IP_VS_DBG(6, "LBLCR hash table (memory=%Zdbytes) released\n",
|
|
sizeof(*tbl));
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
static inline struct ip_vs_dest *
|
|
__ip_vs_lblcr_schedule(struct ip_vs_service *svc)
|
|
{
|
|
struct ip_vs_dest *dest, *least;
|
|
int loh, doh;
|
|
|
|
/*
|
|
* We think the overhead of processing active connections is fifty
|
|
* times higher than that of inactive connections in average. (This
|
|
* fifty times might not be accurate, we will change it later.) We
|
|
* use the following formula to estimate the overhead:
|
|
* dest->activeconns*50 + dest->inactconns
|
|
* and the load:
|
|
* (dest overhead) / dest->weight
|
|
*
|
|
* Remember -- no floats in kernel mode!!!
|
|
* The comparison of h1*w2 > h2*w1 is equivalent to that of
|
|
* h1/w1 > h2/w2
|
|
* if every weight is larger than zero.
|
|
*
|
|
* The server with weight=0 is quiesced and will not receive any
|
|
* new connection.
|
|
*/
|
|
list_for_each_entry(dest, &svc->destinations, n_list) {
|
|
if (dest->flags & IP_VS_DEST_F_OVERLOAD)
|
|
continue;
|
|
|
|
if (atomic_read(&dest->weight) > 0) {
|
|
least = dest;
|
|
loh = atomic_read(&least->activeconns) * 50
|
|
+ atomic_read(&least->inactconns);
|
|
goto nextstage;
|
|
}
|
|
}
|
|
return NULL;
|
|
|
|
/*
|
|
* Find the destination with the least load.
|
|
*/
|
|
nextstage:
|
|
list_for_each_entry_continue(dest, &svc->destinations, n_list) {
|
|
if (dest->flags & IP_VS_DEST_F_OVERLOAD)
|
|
continue;
|
|
|
|
doh = atomic_read(&dest->activeconns) * 50
|
|
+ atomic_read(&dest->inactconns);
|
|
if (loh * atomic_read(&dest->weight) >
|
|
doh * atomic_read(&least->weight)) {
|
|
least = dest;
|
|
loh = doh;
|
|
}
|
|
}
|
|
|
|
IP_VS_DBG_BUF(6, "LBLCR: server %s:%d "
|
|
"activeconns %d refcnt %d weight %d overhead %d\n",
|
|
IP_VS_DBG_ADDR(least->af, &least->addr),
|
|
ntohs(least->port),
|
|
atomic_read(&least->activeconns),
|
|
atomic_read(&least->refcnt),
|
|
atomic_read(&least->weight), loh);
|
|
|
|
return least;
|
|
}
|
|
|
|
|
|
/*
|
|
* If this destination server is overloaded and there is a less loaded
|
|
* server, then return true.
|
|
*/
|
|
static inline int
|
|
is_overloaded(struct ip_vs_dest *dest, struct ip_vs_service *svc)
|
|
{
|
|
if (atomic_read(&dest->activeconns) > atomic_read(&dest->weight)) {
|
|
struct ip_vs_dest *d;
|
|
|
|
list_for_each_entry(d, &svc->destinations, n_list) {
|
|
if (atomic_read(&d->activeconns)*2
|
|
< atomic_read(&d->weight)) {
|
|
return 1;
|
|
}
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
|
|
/*
|
|
* Locality-Based (weighted) Least-Connection scheduling
|
|
*/
|
|
static struct ip_vs_dest *
|
|
ip_vs_lblcr_schedule(struct ip_vs_service *svc, const struct sk_buff *skb)
|
|
{
|
|
struct ip_vs_lblcr_table *tbl = svc->sched_data;
|
|
struct ip_vs_iphdr iph;
|
|
struct ip_vs_dest *dest = NULL;
|
|
struct ip_vs_lblcr_entry *en;
|
|
|
|
ip_vs_fill_iphdr(svc->af, skb_network_header(skb), &iph);
|
|
|
|
IP_VS_DBG(6, "ip_vs_lblcr_schedule(): Scheduling...\n");
|
|
|
|
/* First look in our cache */
|
|
read_lock(&svc->sched_lock);
|
|
en = ip_vs_lblcr_get(svc->af, tbl, &iph.daddr);
|
|
if (en) {
|
|
/* We only hold a read lock, but this is atomic */
|
|
en->lastuse = jiffies;
|
|
|
|
/* Get the least loaded destination */
|
|
read_lock(&en->set.lock);
|
|
dest = ip_vs_dest_set_min(&en->set);
|
|
read_unlock(&en->set.lock);
|
|
|
|
/* More than one destination + enough time passed by, cleanup */
|
|
if (atomic_read(&en->set.size) > 1 &&
|
|
time_after(jiffies, en->set.lastmod +
|
|
sysctl_ip_vs_lblcr_expiration)) {
|
|
struct ip_vs_dest *m;
|
|
|
|
write_lock(&en->set.lock);
|
|
m = ip_vs_dest_set_max(&en->set);
|
|
if (m)
|
|
ip_vs_dest_set_erase(&en->set, m);
|
|
write_unlock(&en->set.lock);
|
|
}
|
|
|
|
/* If the destination is not overloaded, use it */
|
|
if (dest && !is_overloaded(dest, svc)) {
|
|
read_unlock(&svc->sched_lock);
|
|
goto out;
|
|
}
|
|
|
|
/* The cache entry is invalid, time to schedule */
|
|
dest = __ip_vs_lblcr_schedule(svc);
|
|
if (!dest) {
|
|
IP_VS_ERR_RL("LBLCR: no destination available\n");
|
|
read_unlock(&svc->sched_lock);
|
|
return NULL;
|
|
}
|
|
|
|
/* Update our cache entry */
|
|
write_lock(&en->set.lock);
|
|
ip_vs_dest_set_insert(&en->set, dest);
|
|
write_unlock(&en->set.lock);
|
|
}
|
|
read_unlock(&svc->sched_lock);
|
|
|
|
if (dest)
|
|
goto out;
|
|
|
|
/* No cache entry, time to schedule */
|
|
dest = __ip_vs_lblcr_schedule(svc);
|
|
if (!dest) {
|
|
IP_VS_DBG(1, "no destination available\n");
|
|
return NULL;
|
|
}
|
|
|
|
/* If we fail to create a cache entry, we'll just use the valid dest */
|
|
write_lock(&svc->sched_lock);
|
|
ip_vs_lblcr_new(tbl, &iph.daddr, dest);
|
|
write_unlock(&svc->sched_lock);
|
|
|
|
out:
|
|
IP_VS_DBG_BUF(6, "LBLCR: destination IP address %s --> server %s:%d\n",
|
|
IP_VS_DBG_ADDR(svc->af, &iph.daddr),
|
|
IP_VS_DBG_ADDR(svc->af, &dest->addr), ntohs(dest->port));
|
|
|
|
return dest;
|
|
}
|
|
|
|
|
|
/*
|
|
* IPVS LBLCR Scheduler structure
|
|
*/
|
|
static struct ip_vs_scheduler ip_vs_lblcr_scheduler =
|
|
{
|
|
.name = "lblcr",
|
|
.refcnt = ATOMIC_INIT(0),
|
|
.module = THIS_MODULE,
|
|
.n_list = LIST_HEAD_INIT(ip_vs_lblcr_scheduler.n_list),
|
|
.init_service = ip_vs_lblcr_init_svc,
|
|
.done_service = ip_vs_lblcr_done_svc,
|
|
.schedule = ip_vs_lblcr_schedule,
|
|
};
|
|
|
|
|
|
static int __init ip_vs_lblcr_init(void)
|
|
{
|
|
int ret;
|
|
|
|
sysctl_header = register_sysctl_paths(net_vs_ctl_path, vs_vars_table);
|
|
ret = register_ip_vs_scheduler(&ip_vs_lblcr_scheduler);
|
|
if (ret)
|
|
unregister_sysctl_table(sysctl_header);
|
|
return ret;
|
|
}
|
|
|
|
|
|
static void __exit ip_vs_lblcr_cleanup(void)
|
|
{
|
|
unregister_sysctl_table(sysctl_header);
|
|
unregister_ip_vs_scheduler(&ip_vs_lblcr_scheduler);
|
|
}
|
|
|
|
|
|
module_init(ip_vs_lblcr_init);
|
|
module_exit(ip_vs_lblcr_cleanup);
|
|
MODULE_LICENSE("GPL");
|