These changes are the raw update to linux-4.4.6-rt14. Kernel sources

[kvmfornfv.git] / kernel / net / netfilter / ipvs / ip_vs_ovf.c

diff --git a/kernel/net/netfilter/ipvs/ip_vs_ovf.c b/kernel/net/netfilter/ipvs/ip_vs_ovf.c
new file mode 100644 (file)
index 0000000..f7d62c3
--- /dev/null
+++ b/kernel/net/netfilter/ipvs/ip_vs_ovf.c
@@ -0,0 +1,86 @@
+/*
+ * IPVS:        Overflow-Connection Scheduling module
+ *
+ * Authors:     Raducu Deaconu <rhadoo_io@yahoo.com>
+ *
+ *              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.
+ *
+ * Scheduler implements "overflow" loadbalancing according to number of active
+ * connections , will keep all conections to the node with the highest weight
+ * and overflow to the next node if the number of connections exceeds the node's
+ * weight.
+ * Note that this scheduler might not be suitable for UDP because it only uses
+ * active connections
+ *
+ */
+
+#define KMSG_COMPONENT "IPVS"
+#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+
+#include <net/ip_vs.h>
+
+/* OVF Connection scheduling  */
+static struct ip_vs_dest *
+ip_vs_ovf_schedule(struct ip_vs_service *svc, const struct sk_buff *skb,
+                  struct ip_vs_iphdr *iph)
+{
+       struct ip_vs_dest *dest, *h = NULL;
+       int hw = 0, w;
+
+       IP_VS_DBG(6, "ip_vs_ovf_schedule(): Scheduling...\n");
+       /* select the node with highest weight, go to next in line if active
+       * connections exceed weight
+       */
+       list_for_each_entry_rcu(dest, &svc->destinations, n_list) {
+               w = atomic_read(&dest->weight);
+               if ((dest->flags & IP_VS_DEST_F_OVERLOAD) ||
+                   atomic_read(&dest->activeconns) > w ||
+                   w == 0)
+                       continue;
+               if (!h || w > hw) {
+                       h = dest;
+                       hw = w;
+               }
+       }
+
+       if (h) {
+               IP_VS_DBG_BUF(6, "OVF: server %s:%u active %d w %d\n",
+                             IP_VS_DBG_ADDR(h->af, &h->addr),
+                             ntohs(h->port),
+                             atomic_read(&h->activeconns),
+                             atomic_read(&h->weight));
+               return h;
+       }
+
+       ip_vs_scheduler_err(svc, "no destination available");
+       return NULL;
+}
+
+static struct ip_vs_scheduler ip_vs_ovf_scheduler = {
+       .name =                 "ovf",
+       .refcnt =               ATOMIC_INIT(0),
+       .module =               THIS_MODULE,
+       .n_list =               LIST_HEAD_INIT(ip_vs_ovf_scheduler.n_list),
+       .schedule =             ip_vs_ovf_schedule,
+};
+
+static int __init ip_vs_ovf_init(void)
+{
+       return register_ip_vs_scheduler(&ip_vs_ovf_scheduler);
+}
+
+static void __exit ip_vs_ovf_cleanup(void)
+{
+       unregister_ip_vs_scheduler(&ip_vs_ovf_scheduler);
+       synchronize_rcu();
+}
+
+module_init(ip_vs_ovf_init);
+module_exit(ip_vs_ovf_cleanup);
+MODULE_LICENSE("GPL");