Listing 1. Linux Schedule Function
/* Code from sched.c, heavily edited for clarity
and simplicity */
static inline int goodness(struct task_struct * p,
struct task_struct * prev, int this_cpu)
{
int weight;
weight = p->counter;
/* Code to adjust weight */
return weight;
}
asmlinkage void schedule(void)
{
prev = current;
c = -1000;
next = idle_task;
/* The Search Loop */
while (p != &init_task) {
int weight = goodness(p, prev, this_cpu);
if (weight > c)
c = weight, next = p;
p = p->next_run;
}
/* The Recalc Loop */
/* if all runnable processes have "counter == 0",
re-calculate counters */
if (!c) {
for_each_task(p)
p->counter = (p->counter >> 1) + p->priority;
}
}
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