1da177e4c3
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
888 lines
21 KiB
C
888 lines
21 KiB
C
/*
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* IPVS: Locality-Based Least-Connection with Replication scheduler
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*
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* Version: $Id: ip_vs_lblcr.c,v 1.11 2002/09/15 08:14:08 wensong Exp $
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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/module.h>
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#include <linux/kernel.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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/* for proc_net_create/proc_net_remove */
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#include <linux/proc_fs.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(struct ip_vs_dest_list), 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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write_lock(&set->lock);
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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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write_unlock(&set->lock);
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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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write_lock(&set->lock);
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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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write_unlock(&set->lock);
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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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read_lock(&set->lock);
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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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read_unlock(&set->lock);
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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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read_unlock(&set->lock);
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IP_VS_DBG(6, "ip_vs_dest_set_min: server %d.%d.%d.%d:%d "
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"activeconns %d refcnt %d weight %d overhead %d\n",
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NIPQUAD(least->addr), 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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read_lock(&set->lock);
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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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read_unlock(&set->lock);
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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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read_unlock(&set->lock);
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IP_VS_DBG(6, "ip_vs_dest_set_max: server %d.%d.%d.%d:%d "
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"activeconns %d refcnt %d weight %d overhead %d\n",
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NIPQUAD(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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__u32 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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rwlock_t lock; /* lock for this 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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.ctl_name = NET_IPV4_VS_LBLCR_EXPIRE,
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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 ctl_table vs_table[] = {
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{
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.ctl_name = NET_IPV4_VS,
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.procname = "vs",
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.mode = 0555,
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.child = vs_vars_table
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},
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{ .ctl_name = 0 }
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};
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static ctl_table ipv4_table[] = {
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{
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.ctl_name = NET_IPV4,
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.procname = "ipv4",
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.mode = 0555,
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.child = vs_table
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},
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{ .ctl_name = 0 }
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};
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static ctl_table lblcr_root_table[] = {
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{
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.ctl_name = CTL_NET,
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.procname = "net",
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.mode = 0555,
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.child = ipv4_table
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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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/*
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* new/free a ip_vs_lblcr_entry, which is a mapping of a destination
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* IP address to a server.
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*/
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static inline struct ip_vs_lblcr_entry *ip_vs_lblcr_new(__u32 daddr)
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{
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struct ip_vs_lblcr_entry *en;
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en = kmalloc(sizeof(struct ip_vs_lblcr_entry), GFP_ATOMIC);
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if (en == NULL) {
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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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INIT_LIST_HEAD(&en->list);
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en->addr = daddr;
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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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return en;
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}
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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 ip_vs_lblcr_hashkey(__u32 addr)
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{
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return (ntohl(addr)*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 int
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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;
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if (!list_empty(&en->list)) {
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IP_VS_ERR("ip_vs_lblcr_hash(): request for already hashed, "
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"called from %p\n", __builtin_return_address(0));
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return 0;
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}
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/*
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* Hash by destination IP address
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*/
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hash = ip_vs_lblcr_hashkey(en->addr);
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write_lock(&tbl->lock);
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list_add(&en->list, &tbl->bucket[hash]);
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atomic_inc(&tbl->entries);
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write_unlock(&tbl->lock);
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return 1;
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}
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#if 0000
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/*
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* Unhash ip_vs_lblcr_entry from ip_vs_lblcr_table.
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* returns bool success.
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*/
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static int ip_vs_lblcr_unhash(struct ip_vs_lblcr_table *tbl,
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struct ip_vs_lblcr_entry *en)
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{
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if (list_empty(&en->list)) {
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IP_VS_ERR("ip_vs_lblcr_unhash(): request for not hashed entry, "
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"called from %p\n", __builtin_return_address(0));
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return 0;
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}
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/*
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* Remove it from the table
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*/
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write_lock(&tbl->lock);
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list_del(&en->list);
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INIT_LIST_HEAD(&en->list);
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write_unlock(&tbl->lock);
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return 1;
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}
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#endif
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/*
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* Get ip_vs_lblcr_entry associated with supplied parameters.
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*/
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static inline struct ip_vs_lblcr_entry *
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ip_vs_lblcr_get(struct ip_vs_lblcr_table *tbl, __u32 addr)
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{
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unsigned hash;
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struct ip_vs_lblcr_entry *en;
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hash = ip_vs_lblcr_hashkey(addr);
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read_lock(&tbl->lock);
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list_for_each_entry(en, &tbl->bucket[hash], list) {
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if (en->addr == addr) {
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/* HIT */
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read_unlock(&tbl->lock);
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return en;
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}
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}
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read_unlock(&tbl->lock);
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return NULL;
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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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for (i=0; i<IP_VS_LBLCR_TAB_SIZE; i++) {
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write_lock(&tbl->lock);
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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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atomic_dec(&tbl->entries);
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}
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write_unlock(&tbl->lock);
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}
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}
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static inline void ip_vs_lblcr_full_check(struct ip_vs_lblcr_table *tbl)
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{
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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(&tbl->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(&tbl->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_lblcr_table *tbl;
|
|
unsigned long now = jiffies;
|
|
int goal;
|
|
int i, j;
|
|
struct ip_vs_lblcr_entry *en, *nxt;
|
|
|
|
tbl = (struct ip_vs_lblcr_table *)data;
|
|
|
|
if ((tbl->counter % COUNT_FOR_FULL_EXPIRATION) == 0) {
|
|
/* do full expiration check */
|
|
ip_vs_lblcr_full_check(tbl);
|
|
tbl->counter = 1;
|
|
goto out;
|
|
}
|
|
|
|
if (atomic_read(&tbl->entries) <= tbl->max_size) {
|
|
tbl->counter++;
|
|
goto out;
|
|
}
|
|
|
|
goal = (atomic_read(&tbl->entries) - tbl->max_size)*4/3;
|
|
if (goal > tbl->max_size/2)
|
|
goal = tbl->max_size/2;
|
|
|
|
for (i=0, j=tbl->rover; i<IP_VS_LBLCR_TAB_SIZE; i++) {
|
|
j = (j + 1) & IP_VS_LBLCR_TAB_MASK;
|
|
|
|
write_lock(&tbl->lock);
|
|
list_for_each_entry_safe(en, nxt, &tbl->bucket[j], list) {
|
|
if (time_before(now, en->lastuse+ENTRY_TIMEOUT))
|
|
continue;
|
|
|
|
ip_vs_lblcr_free(en);
|
|
atomic_dec(&tbl->entries);
|
|
goal--;
|
|
}
|
|
write_unlock(&tbl->lock);
|
|
if (goal <= 0)
|
|
break;
|
|
}
|
|
tbl->rover = j;
|
|
|
|
out:
|
|
mod_timer(&tbl->periodic_timer, jiffies+CHECK_EXPIRE_INTERVAL);
|
|
}
|
|
|
|
|
|
#ifdef CONFIG_IP_VS_LBLCR_DEBUG
|
|
static struct ip_vs_lblcr_table *lblcr_table_list;
|
|
|
|
/*
|
|
* /proc/net/ip_vs_lblcr to display the mappings of
|
|
* destination IP address <==> its serverSet
|
|
*/
|
|
static int
|
|
ip_vs_lblcr_getinfo(char *buffer, char **start, off_t offset, int length)
|
|
{
|
|
off_t pos=0, begin;
|
|
int len=0, size;
|
|
struct ip_vs_lblcr_table *tbl;
|
|
unsigned long now = jiffies;
|
|
int i;
|
|
struct ip_vs_lblcr_entry *en;
|
|
|
|
tbl = lblcr_table_list;
|
|
|
|
size = sprintf(buffer, "LastTime Dest IP address Server set\n");
|
|
pos += size;
|
|
len += size;
|
|
|
|
for (i=0; i<IP_VS_LBLCR_TAB_SIZE; i++) {
|
|
read_lock_bh(&tbl->lock);
|
|
list_for_each_entry(en, &tbl->bucket[i], list) {
|
|
char tbuf[16];
|
|
struct ip_vs_dest_list *d;
|
|
|
|
sprintf(tbuf, "%u.%u.%u.%u", NIPQUAD(en->addr));
|
|
size = sprintf(buffer+len, "%8lu %-16s ",
|
|
now-en->lastuse, tbuf);
|
|
|
|
read_lock(&en->set.lock);
|
|
for (d=en->set.list; d!=NULL; d=d->next) {
|
|
size += sprintf(buffer+len+size,
|
|
"%u.%u.%u.%u ",
|
|
NIPQUAD(d->dest->addr));
|
|
}
|
|
read_unlock(&en->set.lock);
|
|
size += sprintf(buffer+len+size, "\n");
|
|
len += size;
|
|
pos += size;
|
|
if (pos <= offset)
|
|
len=0;
|
|
if (pos >= offset+length) {
|
|
read_unlock_bh(&tbl->lock);
|
|
goto done;
|
|
}
|
|
}
|
|
read_unlock_bh(&tbl->lock);
|
|
}
|
|
|
|
done:
|
|
begin = len - (pos - offset);
|
|
*start = buffer + begin;
|
|
len -= begin;
|
|
if(len>length)
|
|
len = length;
|
|
return len;
|
|
}
|
|
#endif
|
|
|
|
|
|
static int ip_vs_lblcr_init_svc(struct ip_vs_service *svc)
|
|
{
|
|
int i;
|
|
struct ip_vs_lblcr_table *tbl;
|
|
|
|
/*
|
|
* Allocate the ip_vs_lblcr_table for this service
|
|
*/
|
|
tbl = kmalloc(sizeof(struct ip_vs_lblcr_table), 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(struct ip_vs_lblcr_table));
|
|
|
|
/*
|
|
* Initialize the hash buckets
|
|
*/
|
|
for (i=0; i<IP_VS_LBLCR_TAB_SIZE; i++) {
|
|
INIT_LIST_HEAD(&tbl->bucket[i]);
|
|
}
|
|
rwlock_init(&tbl->lock);
|
|
tbl->max_size = IP_VS_LBLCR_TAB_SIZE*16;
|
|
tbl->rover = 0;
|
|
tbl->counter = 1;
|
|
|
|
/*
|
|
* Hook periodic timer for garbage collection
|
|
*/
|
|
init_timer(&tbl->periodic_timer);
|
|
tbl->periodic_timer.data = (unsigned long)tbl;
|
|
tbl->periodic_timer.function = ip_vs_lblcr_check_expire;
|
|
tbl->periodic_timer.expires = jiffies+CHECK_EXPIRE_INTERVAL;
|
|
add_timer(&tbl->periodic_timer);
|
|
|
|
#ifdef CONFIG_IP_VS_LBLCR_DEBUG
|
|
lblcr_table_list = tbl;
|
|
#endif
|
|
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(svc->sched_data);
|
|
IP_VS_DBG(6, "LBLCR hash table (memory=%Zdbytes) released\n",
|
|
sizeof(struct ip_vs_lblcr_table));
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
static int ip_vs_lblcr_update_svc(struct ip_vs_service *svc)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
|
|
static inline struct ip_vs_dest *
|
|
__ip_vs_wlc_schedule(struct ip_vs_service *svc, struct iphdr *iph)
|
|
{
|
|
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(6, "LBLCR: server %d.%d.%d.%d:%d "
|
|
"activeconns %d refcnt %d weight %d overhead %d\n",
|
|
NIPQUAD(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_dest *dest;
|
|
struct ip_vs_lblcr_table *tbl;
|
|
struct ip_vs_lblcr_entry *en;
|
|
struct iphdr *iph = skb->nh.iph;
|
|
|
|
IP_VS_DBG(6, "ip_vs_lblcr_schedule(): Scheduling...\n");
|
|
|
|
tbl = (struct ip_vs_lblcr_table *)svc->sched_data;
|
|
en = ip_vs_lblcr_get(tbl, iph->daddr);
|
|
if (en == NULL) {
|
|
dest = __ip_vs_wlc_schedule(svc, iph);
|
|
if (dest == NULL) {
|
|
IP_VS_DBG(1, "no destination available\n");
|
|
return NULL;
|
|
}
|
|
en = ip_vs_lblcr_new(iph->daddr);
|
|
if (en == NULL) {
|
|
return NULL;
|
|
}
|
|
ip_vs_dest_set_insert(&en->set, dest);
|
|
ip_vs_lblcr_hash(tbl, en);
|
|
} else {
|
|
dest = ip_vs_dest_set_min(&en->set);
|
|
if (!dest || is_overloaded(dest, svc)) {
|
|
dest = __ip_vs_wlc_schedule(svc, iph);
|
|
if (dest == NULL) {
|
|
IP_VS_DBG(1, "no destination available\n");
|
|
return NULL;
|
|
}
|
|
ip_vs_dest_set_insert(&en->set, dest);
|
|
}
|
|
if (atomic_read(&en->set.size) > 1 &&
|
|
jiffies-en->set.lastmod > sysctl_ip_vs_lblcr_expiration) {
|
|
struct ip_vs_dest *m;
|
|
m = ip_vs_dest_set_max(&en->set);
|
|
if (m)
|
|
ip_vs_dest_set_erase(&en->set, m);
|
|
}
|
|
}
|
|
en->lastuse = jiffies;
|
|
|
|
IP_VS_DBG(6, "LBLCR: destination IP address %u.%u.%u.%u "
|
|
"--> server %u.%u.%u.%u:%d\n",
|
|
NIPQUAD(en->addr),
|
|
NIPQUAD(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,
|
|
.init_service = ip_vs_lblcr_init_svc,
|
|
.done_service = ip_vs_lblcr_done_svc,
|
|
.update_service = ip_vs_lblcr_update_svc,
|
|
.schedule = ip_vs_lblcr_schedule,
|
|
};
|
|
|
|
|
|
static int __init ip_vs_lblcr_init(void)
|
|
{
|
|
INIT_LIST_HEAD(&ip_vs_lblcr_scheduler.n_list);
|
|
sysctl_header = register_sysctl_table(lblcr_root_table, 0);
|
|
#ifdef CONFIG_IP_VS_LBLCR_DEBUG
|
|
proc_net_create("ip_vs_lblcr", 0, ip_vs_lblcr_getinfo);
|
|
#endif
|
|
return register_ip_vs_scheduler(&ip_vs_lblcr_scheduler);
|
|
}
|
|
|
|
|
|
static void __exit ip_vs_lblcr_cleanup(void)
|
|
{
|
|
#ifdef CONFIG_IP_VS_LBLCR_DEBUG
|
|
proc_net_remove("ip_vs_lblcr");
|
|
#endif
|
|
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");
|