src/sd_rr.c

   1 /*
   2  * Lightweight Autonomic Network Architecture
   3  *
   4  * Round robin scheduler.
   5  *
   6  * Copyright 2011 Daniel Borkmann <dborkma@tik.ee.ethz.ch>,
   7  * Swiss federal institute of technology (ETH Zurich)
   8  * Subject to the GPL.
   9  */
  10
  11 #include <linux/module.h>
  12 #include <linux/kernel.h>
  13 #include <linux/cache.h>
  14 #include <linux/cpumask.h>
  15
  16 #include "xt_sched.h"
  17 #include "xt_engine.h"
  18
  19 static volatile unsigned long cpu = 0;
  20 static unsigned long cpu_max;
  21
  22 static int ppe_rr_init(void)
  23 {
  24         cpu_max = num_online_cpus();
  25         return 0;
  26 }
  27
  28 static int ppe_rr_sched(struct sk_buff *skb, enum path_type dir)
  29 {
  30 #ifdef __HIGHPERF
  31         unsigned long ncpu = cpu++ & (cpu_max - 1);
  32         while (ncpu == USERSPACECPU)
  33                 ncpu = cpu++ & (cpu_max - 1);
  34         enqueue_on_engine(skb, ncpu, dir);
  35 #else
  36         enqueue_on_engine(skb, cpu++ & (cpu_max - 1), dir);
  37 #endif
  38         return PPE_SUCCESS;
  39 }
  40
  41 static struct ppesched_discipline_ops ppe_rr_ops __read_mostly = {
  42         .discipline_init = ppe_rr_init,
  43         .discipline_sched = ppe_rr_sched,
  44 };
  45
  46 static struct ppesched_discipline ppe_rr __read_mostly = {
  47         .name = "roundrobin",
  48         .ops = &ppe_rr_ops,
  49         .owner = THIS_MODULE,
  50 };
  51
  52 static int __init init_ppe_rr_module(void)
  53 {
  54         return ppesched_discipline_register(&ppe_rr);
  55 }
  56
  57 static void __exit cleanup_ppe_rr_module(void)
  58 {
  59         return ppesched_discipline_unregister(&ppe_rr);
  60 }
  61
  62 module_init(init_ppe_rr_module);
  63 module_exit(cleanup_ppe_rr_module);
  64
  65 MODULE_LICENSE("GPL");
  66 MODULE_AUTHOR("Daniel Borkmann <dborkma@tik.ee.ethz.ch>");
  67 MODULE_DESCRIPTION("LANA round robin scheduler");
  68