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-rw-r--r--net/ipv4/ipvs/ip_vs_wrr.c234
1 files changed, 0 insertions, 234 deletions
diff --git a/net/ipv4/ipvs/ip_vs_wrr.c b/net/ipv4/ipvs/ip_vs_wrr.c
deleted file mode 100644
index 0d86a79b87b5..000000000000
--- a/net/ipv4/ipvs/ip_vs_wrr.c
+++ /dev/null
@@ -1,234 +0,0 @@
-/*
- * IPVS: Weighted Round-Robin Scheduling module
- *
- * Authors: Wensong Zhang <wensong@linuxvirtualserver.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:
- * Wensong Zhang : changed the ip_vs_wrr_schedule to return dest
- * Wensong Zhang : changed some comestics things for debugging
- * Wensong Zhang : changed for the d-linked destination list
- * Wensong Zhang : added the ip_vs_wrr_update_svc
- * Julian Anastasov : fixed the bug of returning destination
- * with weight 0 when all weights are zero
- *
- */
-
-#include <linux/module.h>
-#include <linux/kernel.h>
-#include <linux/net.h>
-
-#include <net/ip_vs.h>
-
-/*
- * current destination pointer for weighted round-robin scheduling
- */
-struct ip_vs_wrr_mark {
- struct list_head *cl; /* current list head */
- int cw; /* current weight */
- int mw; /* maximum weight */
- int di; /* decreasing interval */
-};
-
-
-/*
- * Get the gcd of server weights
- */
-static int gcd(int a, int b)
-{
- int c;
-
- while ((c = a % b)) {
- a = b;
- b = c;
- }
- return b;
-}
-
-static int ip_vs_wrr_gcd_weight(struct ip_vs_service *svc)
-{
- struct ip_vs_dest *dest;
- int weight;
- int g = 0;
-
- list_for_each_entry(dest, &svc->destinations, n_list) {
- weight = atomic_read(&dest->weight);
- if (weight > 0) {
- if (g > 0)
- g = gcd(weight, g);
- else
- g = weight;
- }
- }
- return g ? g : 1;
-}
-
-
-/*
- * Get the maximum weight of the service destinations.
- */
-static int ip_vs_wrr_max_weight(struct ip_vs_service *svc)
-{
- struct ip_vs_dest *dest;
- int weight = 0;
-
- list_for_each_entry(dest, &svc->destinations, n_list) {
- if (atomic_read(&dest->weight) > weight)
- weight = atomic_read(&dest->weight);
- }
-
- return weight;
-}
-
-
-static int ip_vs_wrr_init_svc(struct ip_vs_service *svc)
-{
- struct ip_vs_wrr_mark *mark;
-
- /*
- * Allocate the mark variable for WRR scheduling
- */
- mark = kmalloc(sizeof(struct ip_vs_wrr_mark), GFP_ATOMIC);
- if (mark == NULL) {
- IP_VS_ERR("ip_vs_wrr_init_svc(): no memory\n");
- return -ENOMEM;
- }
- mark->cl = &svc->destinations;
- mark->cw = 0;
- mark->mw = ip_vs_wrr_max_weight(svc);
- mark->di = ip_vs_wrr_gcd_weight(svc);
- svc->sched_data = mark;
-
- return 0;
-}
-
-
-static int ip_vs_wrr_done_svc(struct ip_vs_service *svc)
-{
- /*
- * Release the mark variable
- */
- kfree(svc->sched_data);
-
- return 0;
-}
-
-
-static int ip_vs_wrr_update_svc(struct ip_vs_service *svc)
-{
- struct ip_vs_wrr_mark *mark = svc->sched_data;
-
- mark->cl = &svc->destinations;
- mark->mw = ip_vs_wrr_max_weight(svc);
- mark->di = ip_vs_wrr_gcd_weight(svc);
- if (mark->cw > mark->mw)
- mark->cw = 0;
- return 0;
-}
-
-
-/*
- * Weighted Round-Robin Scheduling
- */
-static struct ip_vs_dest *
-ip_vs_wrr_schedule(struct ip_vs_service *svc, const struct sk_buff *skb)
-{
- struct ip_vs_dest *dest;
- struct ip_vs_wrr_mark *mark = svc->sched_data;
- struct list_head *p;
-
- IP_VS_DBG(6, "ip_vs_wrr_schedule(): Scheduling...\n");
-
- /*
- * This loop will always terminate, because mark->cw in (0, max_weight]
- * and at least one server has its weight equal to max_weight.
- */
- write_lock(&svc->sched_lock);
- p = mark->cl;
- while (1) {
- if (mark->cl == &svc->destinations) {
- /* it is at the head of the destination list */
-
- if (mark->cl == mark->cl->next) {
- /* no dest entry */
- dest = NULL;
- goto out;
- }
-
- mark->cl = svc->destinations.next;
- mark->cw -= mark->di;
- if (mark->cw <= 0) {
- mark->cw = mark->mw;
- /*
- * Still zero, which means no available servers.
- */
- if (mark->cw == 0) {
- mark->cl = &svc->destinations;
- IP_VS_ERR_RL("ip_vs_wrr_schedule(): "
- "no available servers\n");
- dest = NULL;
- goto out;
- }
- }
- } else
- mark->cl = mark->cl->next;
-
- if (mark->cl != &svc->destinations) {
- /* not at the head of the list */
- dest = list_entry(mark->cl, struct ip_vs_dest, n_list);
- if (!(dest->flags & IP_VS_DEST_F_OVERLOAD) &&
- atomic_read(&dest->weight) >= mark->cw) {
- /* got it */
- break;
- }
- }
-
- if (mark->cl == p && mark->cw == mark->di) {
- /* back to the start, and no dest is found.
- It is only possible when all dests are OVERLOADED */
- dest = NULL;
- goto out;
- }
- }
-
- IP_VS_DBG(6, "WRR: server %u.%u.%u.%u:%u "
- "activeconns %d refcnt %d weight %d\n",
- NIPQUAD(dest->addr), ntohs(dest->port),
- atomic_read(&dest->activeconns),
- atomic_read(&dest->refcnt),
- atomic_read(&dest->weight));
-
- out:
- write_unlock(&svc->sched_lock);
- return dest;
-}
-
-
-static struct ip_vs_scheduler ip_vs_wrr_scheduler = {
- .name = "wrr",
- .refcnt = ATOMIC_INIT(0),
- .module = THIS_MODULE,
- .n_list = LIST_HEAD_INIT(ip_vs_wrr_scheduler.n_list),
- .init_service = ip_vs_wrr_init_svc,
- .done_service = ip_vs_wrr_done_svc,
- .update_service = ip_vs_wrr_update_svc,
- .schedule = ip_vs_wrr_schedule,
-};
-
-static int __init ip_vs_wrr_init(void)
-{
- return register_ip_vs_scheduler(&ip_vs_wrr_scheduler) ;
-}
-
-static void __exit ip_vs_wrr_cleanup(void)
-{
- unregister_ip_vs_scheduler(&ip_vs_wrr_scheduler);
-}
-
-module_init(ip_vs_wrr_init);
-module_exit(ip_vs_wrr_cleanup);
-MODULE_LICENSE("GPL");