Random Walk of Life

Okay, henceforth decided to give the opening and closing mood a break!

Anyway, I am currently reading the Linux scheduler load balancing code. And there’s this one function called find_busiest_group() which looks something like this:

/*
 * find_busiest_group finds and returns the busiest CPU group within the
 * domain. It calculates and returns the amount of weighted load which
 * should be moved to restore balance via the imbalance parameter.
 */
static struct sched_group *
find_busiest_group(struct sched_domain *sd, int this_cpu,
 	   unsigned long *imbalance, enum cpu_idle_type idle,
 	   int *sd_idle, cpumask_t *cpus, int *balance)
{
   struct sched_group *busiest = NULL, *this = NULL, *group = sd->groups;
   unsigned long max_load, avg_load, total_load, this_load, total_pwr;
   unsigned long max_pull;
   unsigned long busiest_load_per_task, busiest_nr_running;
   unsigned long this_load_per_task, this_nr_running;
   int load_idx, group_imb = 0;
  #if defined(CONFIG_SCHED_MC) || defined(CONFIG_SCHED_SMT)
   int power_savings_balance = 1;
   unsigned long leader_nr_running = 0, min_load_per_task = 0;
   unsigned long min_nr_running = ULONG_MAX;
   struct sched_group *group_min = NULL, *group_leader = NULL;
  #endif

	max_load = this_load = total_load = total_pwr = 0;
        busiest_load_per_task = busiest_nr_running = 0;
 this_load_per_task = this_nr_running = 0;
 if (idle == CPU_NOT_IDLE)
 	load_idx = sd->busy_idx;
 else if (idle == CPU_NEWLY_IDLE)
 	load_idx = sd->newidle_idx;
 else
 	load_idx = sd->idle_idx;

	do {
 	unsigned long load, group_capacity, max_cpu_load, min_cpu_load;
 	int local_group;
 	int i;
 	int __group_imb = 0;
 	unsigned int balance_cpu = -1, first_idle_cpu = 0;
 	unsigned long sum_nr_running, sum_weighted_load;

Now by the time I reach this point, I am kinda confused asto what variable holds what value and represents what load exactly!
I guess, I need to increase the stack size of my mind to keep track of soo many local variables!

PS: I apologise for the formatting. The [sourcecode] macro of wordpress cannot do any better than this.
Sathya is planning to write a simple script to convert C code into color coded html instead.