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Diffstat (limited to 'net/ipv4/ipvs/ip_vs_dh.c')
-rw-r--r--net/ipv4/ipvs/ip_vs_dh.c258
1 files changed, 0 insertions, 258 deletions
diff --git a/net/ipv4/ipvs/ip_vs_dh.c b/net/ipv4/ipvs/ip_vs_dh.c
deleted file mode 100644
index fa66824d264..00000000000
--- a/net/ipv4/ipvs/ip_vs_dh.c
+++ /dev/null
@@ -1,258 +0,0 @@
-/*
- * IPVS: Destination Hashing scheduling module
- *
- * Authors: Wensong Zhang <wensong@gnuchina.org>
- *
- * Inspired by the consistent hashing scheduler patch from
- * Thomas Proell <proellt@gmx.de>
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version
- * 2 of the License, or (at your option) any later version.
- *
- * Changes:
- *
- */
-
-/*
- * The dh algorithm is to select server by the hash key of destination IP
- * address. The pseudo code is as follows:
- *
- * n <- servernode[dest_ip];
- * if (n is dead) OR
- * (n is overloaded) OR (n.weight <= 0) then
- * return NULL;
- *
- * return n;
- *
- * Notes that servernode is a 256-bucket hash table that maps the hash
- * index derived from packet destination IP address to the current server
- * array. If the dh scheduler is used in cache cluster, it is good to
- * combine it with cache_bypass feature. When the statically assigned
- * server is dead or overloaded, the load balancer can bypass the cache
- * server and send requests to the original server directly.
- *
- */
-
-#include <linux/ip.h>
-#include <linux/module.h>
-#include <linux/kernel.h>
-#include <linux/skbuff.h>
-
-#include <net/ip_vs.h>
-
-
-/*
- * IPVS DH bucket
- */
-struct ip_vs_dh_bucket {
- struct ip_vs_dest *dest; /* real server (cache) */
-};
-
-/*
- * for IPVS DH entry hash table
- */
-#ifndef CONFIG_IP_VS_DH_TAB_BITS
-#define CONFIG_IP_VS_DH_TAB_BITS 8
-#endif
-#define IP_VS_DH_TAB_BITS CONFIG_IP_VS_DH_TAB_BITS
-#define IP_VS_DH_TAB_SIZE (1 << IP_VS_DH_TAB_BITS)
-#define IP_VS_DH_TAB_MASK (IP_VS_DH_TAB_SIZE - 1)
-
-
-/*
- * Returns hash value for IPVS DH entry
- */
-static inline unsigned ip_vs_dh_hashkey(__be32 addr)
-{
- return (ntohl(addr)*2654435761UL) & IP_VS_DH_TAB_MASK;
-}
-
-
-/*
- * Get ip_vs_dest associated with supplied parameters.
- */
-static inline struct ip_vs_dest *
-ip_vs_dh_get(struct ip_vs_dh_bucket *tbl, __be32 addr)
-{
- return (tbl[ip_vs_dh_hashkey(addr)]).dest;
-}
-
-
-/*
- * Assign all the hash buckets of the specified table with the service.
- */
-static int
-ip_vs_dh_assign(struct ip_vs_dh_bucket *tbl, struct ip_vs_service *svc)
-{
- int i;
- struct ip_vs_dh_bucket *b;
- struct list_head *p;
- struct ip_vs_dest *dest;
-
- b = tbl;
- p = &svc->destinations;
- for (i=0; i<IP_VS_DH_TAB_SIZE; i++) {
- if (list_empty(p)) {
- b->dest = NULL;
- } else {
- if (p == &svc->destinations)
- p = p->next;
-
- dest = list_entry(p, struct ip_vs_dest, n_list);
- atomic_inc(&dest->refcnt);
- b->dest = dest;
-
- p = p->next;
- }
- b++;
- }
- return 0;
-}
-
-
-/*
- * Flush all the hash buckets of the specified table.
- */
-static void ip_vs_dh_flush(struct ip_vs_dh_bucket *tbl)
-{
- int i;
- struct ip_vs_dh_bucket *b;
-
- b = tbl;
- for (i=0; i<IP_VS_DH_TAB_SIZE; i++) {
- if (b->dest) {
- atomic_dec(&b->dest->refcnt);
- b->dest = NULL;
- }
- b++;
- }
-}
-
-
-static int ip_vs_dh_init_svc(struct ip_vs_service *svc)
-{
- struct ip_vs_dh_bucket *tbl;
-
- /* allocate the DH table for this service */
- tbl = kmalloc(sizeof(struct ip_vs_dh_bucket)*IP_VS_DH_TAB_SIZE,
- GFP_ATOMIC);
- if (tbl == NULL) {
- IP_VS_ERR("ip_vs_dh_init_svc(): no memory\n");
- return -ENOMEM;
- }
- svc->sched_data = tbl;
- IP_VS_DBG(6, "DH hash table (memory=%Zdbytes) allocated for "
- "current service\n",
- sizeof(struct ip_vs_dh_bucket)*IP_VS_DH_TAB_SIZE);
-
- /* assign the hash buckets with the updated service */
- ip_vs_dh_assign(tbl, svc);
-
- return 0;
-}
-
-
-static int ip_vs_dh_done_svc(struct ip_vs_service *svc)
-{
- struct ip_vs_dh_bucket *tbl = svc->sched_data;
-
- /* got to clean up hash buckets here */
- ip_vs_dh_flush(tbl);
-
- /* release the table itself */
- kfree(svc->sched_data);
- IP_VS_DBG(6, "DH hash table (memory=%Zdbytes) released\n",
- sizeof(struct ip_vs_dh_bucket)*IP_VS_DH_TAB_SIZE);
-
- return 0;
-}
-
-
-static int ip_vs_dh_update_svc(struct ip_vs_service *svc)
-{
- struct ip_vs_dh_bucket *tbl = svc->sched_data;
-
- /* got to clean up hash buckets here */
- ip_vs_dh_flush(tbl);
-
- /* assign the hash buckets with the updated service */
- ip_vs_dh_assign(tbl, svc);
-
- return 0;
-}
-
-
-/*
- * If the dest flags is set with IP_VS_DEST_F_OVERLOAD,
- * consider that the server is overloaded here.
- */
-static inline int is_overloaded(struct ip_vs_dest *dest)
-{
- return dest->flags & IP_VS_DEST_F_OVERLOAD;
-}
-
-
-/*
- * Destination hashing scheduling
- */
-static struct ip_vs_dest *
-ip_vs_dh_schedule(struct ip_vs_service *svc, const struct sk_buff *skb)
-{
- struct ip_vs_dest *dest;
- struct ip_vs_dh_bucket *tbl;
- struct iphdr *iph = ip_hdr(skb);
-
- IP_VS_DBG(6, "ip_vs_dh_schedule(): Scheduling...\n");
-
- tbl = (struct ip_vs_dh_bucket *)svc->sched_data;
- dest = ip_vs_dh_get(tbl, iph->daddr);
- if (!dest
- || !(dest->flags & IP_VS_DEST_F_AVAILABLE)
- || atomic_read(&dest->weight) <= 0
- || is_overloaded(dest)) {
- return NULL;
- }
-
- IP_VS_DBG(6, "DH: destination IP address %u.%u.%u.%u "
- "--> server %u.%u.%u.%u:%d\n",
- NIPQUAD(iph->daddr),
- NIPQUAD(dest->addr),
- ntohs(dest->port));
-
- return dest;
-}
-
-
-/*
- * IPVS DH Scheduler structure
- */
-static struct ip_vs_scheduler ip_vs_dh_scheduler =
-{
- .name = "dh",
- .refcnt = ATOMIC_INIT(0),
- .module = THIS_MODULE,
- .n_list = LIST_HEAD_INIT(ip_vs_dh_scheduler.n_list),
- .init_service = ip_vs_dh_init_svc,
- .done_service = ip_vs_dh_done_svc,
- .update_service = ip_vs_dh_update_svc,
- .schedule = ip_vs_dh_schedule,
-};
-
-
-static int __init ip_vs_dh_init(void)
-{
- return register_ip_vs_scheduler(&ip_vs_dh_scheduler);
-}
-
-
-static void __exit ip_vs_dh_cleanup(void)
-{
- unregister_ip_vs_scheduler(&ip_vs_dh_scheduler);
-}
-
-
-module_init(ip_vs_dh_init);
-module_exit(ip_vs_dh_cleanup);
-MODULE_LICENSE("GPL");
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-24 05:21:53 +0000