mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-12-15 23:14:31 +08:00
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!
124 lines
3.1 KiB
C
124 lines
3.1 KiB
C
/*
|
|
* IPVS: Least-Connection Scheduling module
|
|
*
|
|
* Version: $Id: ip_vs_lc.c,v 1.10 2003/04/18 09:03:16 wensong Exp $
|
|
*
|
|
* 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 : added the ip_vs_lc_update_svc
|
|
* Wensong Zhang : added any dest with weight=0 is quiesced
|
|
*
|
|
*/
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/kernel.h>
|
|
|
|
#include <net/ip_vs.h>
|
|
|
|
|
|
static int ip_vs_lc_init_svc(struct ip_vs_service *svc)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
|
|
static int ip_vs_lc_done_svc(struct ip_vs_service *svc)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
|
|
static int ip_vs_lc_update_svc(struct ip_vs_service *svc)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
|
|
static inline unsigned int
|
|
ip_vs_lc_dest_overhead(struct ip_vs_dest *dest)
|
|
{
|
|
/*
|
|
* We think the overhead of processing active connections is 256
|
|
* times higher than that of inactive connections in average. (This
|
|
* 256 times might not be accurate, we will change it later) We
|
|
* use the following formula to estimate the overhead now:
|
|
* dest->activeconns*256 + dest->inactconns
|
|
*/
|
|
return (atomic_read(&dest->activeconns) << 8) +
|
|
atomic_read(&dest->inactconns);
|
|
}
|
|
|
|
|
|
/*
|
|
* Least Connection scheduling
|
|
*/
|
|
static struct ip_vs_dest *
|
|
ip_vs_lc_schedule(struct ip_vs_service *svc, const struct sk_buff *skb)
|
|
{
|
|
struct ip_vs_dest *dest, *least = NULL;
|
|
unsigned int loh = 0, doh;
|
|
|
|
IP_VS_DBG(6, "ip_vs_lc_schedule(): Scheduling...\n");
|
|
|
|
/*
|
|
* Simply select the server with the least number of
|
|
* (activeconns<<5) + inactconns
|
|
* Except whose weight is equal to zero.
|
|
* If the weight is equal to zero, it means that the server is
|
|
* quiesced, the existing connections to the server still get
|
|
* served, but no new connection is assigned to the server.
|
|
*/
|
|
|
|
list_for_each_entry(dest, &svc->destinations, n_list) {
|
|
if ((dest->flags & IP_VS_DEST_F_OVERLOAD) ||
|
|
atomic_read(&dest->weight) == 0)
|
|
continue;
|
|
doh = ip_vs_lc_dest_overhead(dest);
|
|
if (!least || doh < loh) {
|
|
least = dest;
|
|
loh = doh;
|
|
}
|
|
}
|
|
|
|
if (least)
|
|
IP_VS_DBG(6, "LC: server %u.%u.%u.%u:%u activeconns %d inactconns %d\n",
|
|
NIPQUAD(least->addr), ntohs(least->port),
|
|
atomic_read(&least->activeconns),
|
|
atomic_read(&least->inactconns));
|
|
|
|
return least;
|
|
}
|
|
|
|
|
|
static struct ip_vs_scheduler ip_vs_lc_scheduler = {
|
|
.name = "lc",
|
|
.refcnt = ATOMIC_INIT(0),
|
|
.module = THIS_MODULE,
|
|
.init_service = ip_vs_lc_init_svc,
|
|
.done_service = ip_vs_lc_done_svc,
|
|
.update_service = ip_vs_lc_update_svc,
|
|
.schedule = ip_vs_lc_schedule,
|
|
};
|
|
|
|
|
|
static int __init ip_vs_lc_init(void)
|
|
{
|
|
INIT_LIST_HEAD(&ip_vs_lc_scheduler.n_list);
|
|
return register_ip_vs_scheduler(&ip_vs_lc_scheduler) ;
|
|
}
|
|
|
|
static void __exit ip_vs_lc_cleanup(void)
|
|
{
|
|
unregister_ip_vs_scheduler(&ip_vs_lc_scheduler);
|
|
}
|
|
|
|
module_init(ip_vs_lc_init);
|
|
module_exit(ip_vs_lc_cleanup);
|
|
MODULE_LICENSE("GPL");
|