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author | David S. Miller <davem@davemloft.net> | 2008-10-11 12:39:35 -0700 |
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committer | David S. Miller <davem@davemloft.net> | 2008-10-11 12:39:35 -0700 |
commit | 56c5d900dbb8e042bfad035d18433476931d8f93 (patch) | |
tree | 00b793965beeef10db03e0ff021d2d965c410759 /net/ipv4/ipvs/ip_vs_wrr.c | |
parent | 4dd95b63ae25c5cad6986829b5e8788e9faa0330 (diff) | |
parent | ead9d23d803ea3a73766c3cb27bf7563ac8d7266 (diff) | |
download | op-kernel-dev-56c5d900dbb8e042bfad035d18433476931d8f93.zip op-kernel-dev-56c5d900dbb8e042bfad035d18433476931d8f93.tar.gz |
Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6
Conflicts:
sound/core/memalloc.c
Diffstat (limited to 'net/ipv4/ipvs/ip_vs_wrr.c')
-rw-r--r-- | net/ipv4/ipvs/ip_vs_wrr.c | 234 |
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 0d86a79..0000000 --- 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"); |