diff options
Diffstat (limited to 'net/ipv4/ipvs/ip_vs_lblcr.c')
| -rw-r--r-- | net/ipv4/ipvs/ip_vs_lblcr.c | 760 |
1 files changed, 0 insertions, 760 deletions
diff --git a/net/ipv4/ipvs/ip_vs_lblcr.c b/net/ipv4/ipvs/ip_vs_lblcr.c deleted file mode 100644 index 8e3bbeb4513..00000000000 --- a/net/ipv4/ipvs/ip_vs_lblcr.c +++ /dev/null @@ -1,760 +0,0 @@ -/* - * IPVS: Locality-Based Least-Connection with Replication scheduler - * - * Authors: Wensong Zhang <wensong@gnuchina.org> - * - * 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. - * - * Changes: - * Julian Anastasov : Added the missing (dest->weight>0) - * condition in the ip_vs_dest_set_max. - * - */ - -/* - * The lblc/r algorithm is as follows (pseudo code): - * - * if serverSet[dest_ip] is null then - * n, serverSet[dest_ip] <- {weighted least-conn node}; - * else - * n <- {least-conn (alive) node in serverSet[dest_ip]}; - * if (n is null) OR - * (n.conns>n.weight AND - * there is a node m with m.conns<m.weight/2) then - * n <- {weighted least-conn node}; - * add n to serverSet[dest_ip]; - * if |serverSet[dest_ip]| > 1 AND - * now - serverSet[dest_ip].lastMod > T then - * m <- {most conn node in serverSet[dest_ip]}; - * remove m from serverSet[dest_ip]; - * if serverSet[dest_ip] changed then - * serverSet[dest_ip].lastMod <- now; - * - * return n; - * - */ - -#include <linux/ip.h> -#include <linux/module.h> -#include <linux/kernel.h> -#include <linux/skbuff.h> -#include <linux/jiffies.h> - -/* for sysctl */ -#include <linux/fs.h> -#include <linux/sysctl.h> -#include <net/net_namespace.h> - -#include <net/ip_vs.h> - - -/* - * It is for garbage collection of stale IPVS lblcr entries, - * when the table is full. - */ -#define CHECK_EXPIRE_INTERVAL (60*HZ) -#define ENTRY_TIMEOUT (6*60*HZ) - -/* - * It is for full expiration check. - * When there is no partial expiration check (garbage collection) - * in a half hour, do a full expiration check to collect stale - * entries that haven't been touched for a day. - */ -#define COUNT_FOR_FULL_EXPIRATION 30 -static int sysctl_ip_vs_lblcr_expiration = 24*60*60*HZ; - - -/* - * for IPVS lblcr entry hash table - */ -#ifndef CONFIG_IP_VS_LBLCR_TAB_BITS -#define CONFIG_IP_VS_LBLCR_TAB_BITS 10 -#endif -#define IP_VS_LBLCR_TAB_BITS CONFIG_IP_VS_LBLCR_TAB_BITS -#define IP_VS_LBLCR_TAB_SIZE (1 << IP_VS_LBLCR_TAB_BITS) -#define IP_VS_LBLCR_TAB_MASK (IP_VS_LBLCR_TAB_SIZE - 1) - - -/* - * IPVS destination set structure and operations - */ -struct ip_vs_dest_list { - struct ip_vs_dest_list *next; /* list link */ - struct ip_vs_dest *dest; /* destination server */ -}; - -struct ip_vs_dest_set { - atomic_t size; /* set size */ - unsigned long lastmod; /* last modified time */ - struct ip_vs_dest_list *list; /* destination list */ - rwlock_t lock; /* lock for this list */ -}; - - -static struct ip_vs_dest_list * -ip_vs_dest_set_insert(struct ip_vs_dest_set *set, struct ip_vs_dest *dest) -{ - struct ip_vs_dest_list *e; - - for (e=set->list; e!=NULL; e=e->next) { - if (e->dest == dest) - /* already existed */ - return NULL; - } - - e = kmalloc(sizeof(struct ip_vs_dest_list), GFP_ATOMIC); - if (e == NULL) { - IP_VS_ERR("ip_vs_dest_set_insert(): no memory\n"); - return NULL; - } - - atomic_inc(&dest->refcnt); - e->dest = dest; - - /* link it to the list */ - write_lock(&set->lock); - e->next = set->list; - set->list = e; - atomic_inc(&set->size); - write_unlock(&set->lock); - - set->lastmod = jiffies; - return e; -} - -static void -ip_vs_dest_set_erase(struct ip_vs_dest_set *set, struct ip_vs_dest *dest) -{ - struct ip_vs_dest_list *e, **ep; - - write_lock(&set->lock); - for (ep=&set->list, e=*ep; e!=NULL; e=*ep) { - if (e->dest == dest) { - /* HIT */ - *ep = e->next; - atomic_dec(&set->size); - set->lastmod = jiffies; - atomic_dec(&e->dest->refcnt); - kfree(e); - break; - } - ep = &e->next; - } - write_unlock(&set->lock); -} - -static void ip_vs_dest_set_eraseall(struct ip_vs_dest_set *set) -{ - struct ip_vs_dest_list *e, **ep; - - write_lock(&set->lock); - for (ep=&set->list, e=*ep; e!=NULL; e=*ep) { - *ep = e->next; - /* - * We don't kfree dest because it is refered either - * by its service or by the trash dest list. - */ - atomic_dec(&e->dest->refcnt); - kfree(e); - } - write_unlock(&set->lock); -} - -/* get weighted least-connection node in the destination set */ -static inline struct ip_vs_dest *ip_vs_dest_set_min(struct ip_vs_dest_set *set) -{ - register struct ip_vs_dest_list *e; - struct ip_vs_dest *dest, *least; - int loh, doh; - - if (set == NULL) - return NULL; - - read_lock(&set->lock); - /* select the first destination server, whose weight > 0 */ - for (e=set->list; e!=NULL; e=e->next) { - least = e->dest; - if (least->flags & IP_VS_DEST_F_OVERLOAD) - continue; - - if ((atomic_read(&least->weight) > 0) - && (least->flags & IP_VS_DEST_F_AVAILABLE)) { - loh = atomic_read(&least->activeconns) * 50 - + atomic_read(&least->inactconns); - goto nextstage; - } - } - read_unlock(&set->lock); - return NULL; - - /* find the destination with the weighted least load */ - nextstage: - for (e=e->next; e!=NULL; e=e->next) { - dest = e->dest; - 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)) - && (dest->flags & IP_VS_DEST_F_AVAILABLE)) { - least = dest; - loh = doh; - } - } - read_unlock(&set->lock); - - IP_VS_DBG(6, "ip_vs_dest_set_min: 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; -} - - -/* get weighted most-connection node in the destination set */ -static inline struct ip_vs_dest *ip_vs_dest_set_max(struct ip_vs_dest_set *set) -{ - register struct ip_vs_dest_list *e; - struct ip_vs_dest *dest, *most; - int moh, doh; - - if (set == NULL) - return NULL; - - read_lock(&set->lock); - /* select the first destination server, whose weight > 0 */ - for (e=set->list; e!=NULL; e=e->next) { - most = e->dest; - if (atomic_read(&most->weight) > 0) { - moh = atomic_read(&most->activeconns) * 50 - + atomic_read(&most->inactconns); - goto nextstage; - } - } - read_unlock(&set->lock); - return NULL; - - /* find the destination with the weighted most load */ - nextstage: - for (e=e->next; e!=NULL; e=e->next) { - dest = e->dest; - doh = atomic_read(&dest->activeconns) * 50 - + atomic_read(&dest->inactconns); - /* moh/mw < doh/dw ==> moh*dw < doh*mw, where mw,dw>0 */ - if ((moh * atomic_read(&dest->weight) < - doh * atomic_read(&most->weight)) - && (atomic_read(&dest->weight) > 0)) { - most = dest; - moh = doh; - } - } - read_unlock(&set->lock); - - IP_VS_DBG(6, "ip_vs_dest_set_max: server %d.%d.%d.%d:%d " - "activeconns %d refcnt %d weight %d overhead %d\n", - NIPQUAD(most->addr), ntohs(most->port), - atomic_read(&most->activeconns), - atomic_read(&most->refcnt), - atomic_read(&most->weight), moh); - return most; -} - - -/* - * IPVS lblcr entry represents an association between destination - * IP address and its destination server set - */ -struct ip_vs_lblcr_entry { - struct list_head list; - __be32 addr; /* destination IP address */ - struct ip_vs_dest_set set; /* destination server set */ - unsigned long lastuse; /* last used time */ -}; - - -/* - * IPVS lblcr hash table - */ -struct ip_vs_lblcr_table { - rwlock_t lock; /* lock for this table */ - struct list_head bucket[IP_VS_LBLCR_TAB_SIZE]; /* hash bucket */ - atomic_t entries; /* number of entries */ - int max_size; /* maximum size of entries */ - struct timer_list periodic_timer; /* collect stale entries */ - int rover; /* rover for expire check */ - int counter; /* counter for no expire */ -}; - - -/* - * IPVS LBLCR sysctl table - */ - -static ctl_table vs_vars_table[] = { - { - .procname = "lblcr_expiration", - .data = &sysctl_ip_vs_lblcr_expiration, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = &proc_dointvec_jiffies, - }, - { .ctl_name = 0 } -}; - -static struct ctl_table_header * sysctl_header; - -/* - * new/free a ip_vs_lblcr_entry, which is a mapping of a destination - * IP address to a server. - */ -static inline struct ip_vs_lblcr_entry *ip_vs_lblcr_new(__be32 daddr) -{ - struct ip_vs_lblcr_entry *en; - - en = kmalloc(sizeof(struct ip_vs_lblcr_entry), GFP_ATOMIC); - if (en == NULL) { - IP_VS_ERR("ip_vs_lblcr_new(): no memory\n"); - return NULL; - } - - INIT_LIST_HEAD(&en->list); - en->addr = daddr; - - /* initilize its dest set */ - atomic_set(&(en->set.size), 0); - en->set.list = NULL; - rwlock_init(&en->set.lock); - - return en; -} - - -static inline void ip_vs_lblcr_free(struct ip_vs_lblcr_entry *en) -{ - list_del(&en->list); - ip_vs_dest_set_eraseall(&en->set); - kfree(en); -} - - -/* - * Returns hash value for IPVS LBLCR entry - */ -static inline unsigned ip_vs_lblcr_hashkey(__be32 addr) -{ - return (ntohl(addr)*2654435761UL) & IP_VS_LBLCR_TAB_MASK; -} - - -/* - * Hash an entry in the ip_vs_lblcr_table. - * returns bool success. - */ -static int -ip_vs_lblcr_hash(struct ip_vs_lblcr_table *tbl, struct ip_vs_lblcr_entry *en) -{ - unsigned hash; - - if (!list_empty(&en->list)) { - IP_VS_ERR("ip_vs_lblcr_hash(): request for already hashed, " - "called from %p\n", __builtin_return_address(0)); - return 0; - } - - /* - * Hash by destination IP address - */ - hash = ip_vs_lblcr_hashkey(en->addr); - - write_lock(&tbl->lock); - list_add(&en->list, &tbl->bucket[hash]); - atomic_inc(&tbl->entries); - write_unlock(&tbl->lock); - - return 1; -} - - -/* - * Get ip_vs_lblcr_entry associated with supplied parameters. - */ -static inline struct ip_vs_lblcr_entry * -ip_vs_lblcr_get(struct ip_vs_lblcr_table *tbl, __be32 addr) -{ - unsigned hash; - struct ip_vs_lblcr_entry *en; - - hash = ip_vs_lblcr_hashkey(addr); - - read_lock(&tbl->lock); - - list_for_each_entry(en, &tbl->bucket[hash], list) { - if (en->addr == addr) { - /* HIT */ - read_unlock(&tbl->lock); - return en; - } - } - - read_unlock(&tbl->lock); - - return NULL; -} - - -/* - * Flush all the entries of the specified table. - */ -static void ip_vs_lblcr_flush(struct ip_vs_lblcr_table *tbl) -{ - int i; - struct ip_vs_lblcr_entry *en, *nxt; - - for (i=0; i<IP_VS_LBLCR_TAB_SIZE; i++) { - write_lock(&tbl->lock); - list_for_each_entry_safe(en, nxt, &tbl->bucket[i], list) { - ip_vs_lblcr_free(en); - atomic_dec(&tbl->entries); - } - write_unlock(&tbl->lock); - } -} - - -static inline void ip_vs_lblcr_full_check(struct ip_vs_lblcr_table *tbl) -{ - unsigned long now = jiffies; - int i, j; - struct ip_vs_lblcr_entry *en, *nxt; - - 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_after(en->lastuse+sysctl_ip_vs_lblcr_expiration, - now)) - continue; - - ip_vs_lblcr_free(en); - atomic_dec(&tbl->entries); - } - write_unlock(&tbl->lock); - } - tbl->rover = j; -} - - -/* - * Periodical timer handler for IPVS lblcr table - * It is used to collect stale entries when the number of entries - * exceeds the maximum size of the table. - * - * Fixme: we probably need more complicated algorithm to collect - * entries that have not been used for a long time even - * if the number of entries doesn't exceed the maximum size - * of the table. - * The full expiration check is for this purpose now. - */ -static void ip_vs_lblcr_check_expire(unsigned long data) -{ - 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); -} - -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 - */ - setup_timer(&tbl->periodic_timer, ip_vs_lblcr_check_expire, - (unsigned long)tbl); - tbl->periodic_timer.expires = jiffies+CHECK_EXPIRE_INTERVAL; - add_timer(&tbl->periodic_timer); - - 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 = ip_hdr(skb); - - 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) -{ - int ret; - - INIT_LIST_HEAD(&ip_vs_lblcr_scheduler.n_list); - 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"); |