Kenny Mathis | 616a9be | 2014-09-09 09:20:15 -0400 | [diff] [blame] | 1 | /* |
| 2 | * IPVS: Weighted Fail Over module |
| 3 | * |
| 4 | * Authors: Kenny Mathis <kmathis@chokepoint.net> |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or |
| 7 | * modify it under the terms of the GNU General Public License |
| 8 | * as published by the Free Software Foundation; either version |
| 9 | * 2 of the License, or (at your option) any later version. |
| 10 | * |
| 11 | * Changes: |
| 12 | * Kenny Mathis : added initial functionality based on weight |
| 13 | * |
| 14 | */ |
| 15 | |
| 16 | #define KMSG_COMPONENT "IPVS" |
| 17 | #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt |
| 18 | |
| 19 | #include <linux/module.h> |
| 20 | #include <linux/kernel.h> |
| 21 | |
| 22 | #include <net/ip_vs.h> |
| 23 | |
| 24 | /* Weighted Fail Over Module */ |
| 25 | static struct ip_vs_dest * |
| 26 | ip_vs_fo_schedule(struct ip_vs_service *svc, const struct sk_buff *skb, |
| 27 | struct ip_vs_iphdr *iph) |
| 28 | { |
| 29 | struct ip_vs_dest *dest, *hweight = NULL; |
| 30 | int hw = 0; /* Track highest weight */ |
| 31 | |
| 32 | IP_VS_DBG(6, "ip_vs_fo_schedule(): Scheduling...\n"); |
| 33 | |
| 34 | /* Basic failover functionality |
| 35 | * Find virtual server with highest weight and send it traffic |
| 36 | */ |
| 37 | list_for_each_entry_rcu(dest, &svc->destinations, n_list) { |
| 38 | if (!(dest->flags & IP_VS_DEST_F_OVERLOAD) && |
| 39 | atomic_read(&dest->weight) > hw) { |
| 40 | hweight = dest; |
| 41 | hw = atomic_read(&dest->weight); |
| 42 | } |
| 43 | } |
| 44 | |
| 45 | if (hweight) { |
| 46 | IP_VS_DBG_BUF(6, "FO: server %s:%u activeconns %d weight %d\n", |
Julian Anastasov | 4d316f3 | 2014-09-17 00:09:00 +0300 | [diff] [blame] | 47 | IP_VS_DBG_ADDR(hweight->af, &hweight->addr), |
Kenny Mathis | 616a9be | 2014-09-09 09:20:15 -0400 | [diff] [blame] | 48 | ntohs(hweight->port), |
| 49 | atomic_read(&hweight->activeconns), |
| 50 | atomic_read(&hweight->weight)); |
| 51 | return hweight; |
| 52 | } |
| 53 | |
| 54 | ip_vs_scheduler_err(svc, "no destination available"); |
| 55 | return NULL; |
| 56 | } |
| 57 | |
| 58 | static struct ip_vs_scheduler ip_vs_fo_scheduler = { |
| 59 | .name = "fo", |
| 60 | .refcnt = ATOMIC_INIT(0), |
| 61 | .module = THIS_MODULE, |
| 62 | .n_list = LIST_HEAD_INIT(ip_vs_fo_scheduler.n_list), |
| 63 | .schedule = ip_vs_fo_schedule, |
| 64 | }; |
| 65 | |
| 66 | static int __init ip_vs_fo_init(void) |
| 67 | { |
| 68 | return register_ip_vs_scheduler(&ip_vs_fo_scheduler); |
| 69 | } |
| 70 | |
| 71 | static void __exit ip_vs_fo_cleanup(void) |
| 72 | { |
| 73 | unregister_ip_vs_scheduler(&ip_vs_fo_scheduler); |
| 74 | synchronize_rcu(); |
| 75 | } |
| 76 | |
| 77 | module_init(ip_vs_fo_init); |
| 78 | module_exit(ip_vs_fo_cleanup); |
| 79 | MODULE_LICENSE("GPL"); |