#include <linux/init.h>
#include <linux/ckrm_sched.h>
-rwlock_t class_list_lock = RW_LOCK_UNLOCKED;
-LIST_HEAD(active_cpu_classes); // list of active cpu classes; anchor
-
-struct ckrm_cpu_class default_cpu_class_obj;
-
-struct ckrm_cpu_class * get_default_cpu_class(void) {
- return (&default_cpu_class_obj);
-}
-
/*******************************************************/
/* CVT Management */
/*******************************************************/
+#define CVT_WINDOW_SIZE (CLASSQUEUE_SIZE << CLASS_BONUS_RATE)
+static CVT_t max_CVT = CVT_WINDOW_SIZE;
-static inline void check_inactive_class(ckrm_lrq_t * lrq,CVT_t cur_cvt)
+/*
+ * Also ensure that the classes global cvt is upgraded to the
+ * minimum CVT in the system, as a class might not have run for a while
+ */
+static void update_global_cvt(struct ckrm_cpu_class *cpu_class, int cpu)
{
+ struct ckrm_local_runqueue *class_queue =
+ get_ckrm_local_runqueue(cpu_class, cpu);
CVT_t min_cvt;
- CVT_t bonus;
-
- //just a safty measure
- if (unlikely(! cur_cvt))
- return;
+ CVT_t local_cvt_old = class_queue->local_cvt;
-#ifndef INTERACTIVE_BONUS_SUPPORT
-#warning "ACB taking out interactive bonus calculation"
- bonus = 0;
-#else
- /*
- * Always leaving a small bonus for inactive classes
- * allows them to compete for cycles immediately when the become
- * active. This should improve interactive behavior
- */
- bonus = INTERACTIVE_BONUS(lrq);
+ spin_lock(&cvt_lock);
+ if (class_queue->uncounted_cvt) {
+ cpu_class->global_cvt += class_queue->uncounted_cvt;
+ class_queue->uncounted_cvt = 0;
+ }
+ min_cvt = max_CVT - CVT_WINDOW_SIZE;
+ if (cpu_class->global_cvt < min_cvt)
+ cpu_class->global_cvt = min_cvt;
+ else if (cpu_class->global_cvt > max_CVT)
+ max_CVT = cpu_class->global_cvt;
+
+/* update local cvt from global cvt*/
+#if 0
+ class_queue->local_cvt = cpu_class->global_cvt;
#endif
+ spin_unlock(&cvt_lock);
- //cvt can't be negative
- if (cur_cvt > bonus)
- min_cvt = cur_cvt - bonus;
- else
- min_cvt = 0;
-
- if (lrq->local_cvt < min_cvt) {
- CVT_t lost_cvt;
-
- lost_cvt = scale_cvt(min_cvt - lrq->local_cvt,lrq);
- lrq->local_cvt = min_cvt;
-
- /* add what the class lost to its savings*/
- lrq->savings += lost_cvt;
- if (lrq->savings > MAX_SAVINGS)
- lrq->savings = MAX_SAVINGS;
- } else if (lrq->savings) {
- /*
- *if a class saving and falling behind
- * then start to use it saving in a leaking bucket way
- */
- CVT_t savings_used;
-
- savings_used = scale_cvt((lrq->local_cvt - min_cvt),lrq);
- if (savings_used > lrq->savings)
- savings_used = lrq->savings;
-
- if (savings_used > SAVINGS_LEAK_SPEED)
- savings_used = SAVINGS_LEAK_SPEED;
-
- BUG_ON(lrq->savings < savings_used);
- lrq->savings -= savings_used;
- unscale_cvt(savings_used,lrq);
- BUG_ON(lrq->local_cvt < savings_used);
-#ifndef CVT_SAVINGS_SUPPORT
-#warning "ACB taking out cvt saving"
-#else
- lrq->local_cvt -= savings_used;
-#endif
- }
+ if (class_queue->local_cvt != local_cvt_old)
+ update_class_priority(class_queue);
}
/*
- * return the max_cvt of all the classes
- */
-static inline CVT_t get_max_cvt(int this_cpu)
-{
- struct ckrm_cpu_class *clsptr;
- ckrm_lrq_t * lrq;
- CVT_t max_cvt;
-
- max_cvt = 0;
-
- /*update class time, at the same time get max_cvt */
- list_for_each_entry(clsptr, &active_cpu_classes, links) {
- lrq = get_ckrm_lrq(clsptr, this_cpu);
- if (lrq->local_cvt > max_cvt)
- max_cvt = lrq->local_cvt;
- }
-
- return max_cvt;
-}
-
-/**
- * update_class_cputime - updates cvt of inactive classes
- * -- an inactive class shouldn't starve others when it comes back
- * -- the cpu time it lost when it's inactive should be accumulated
- * -- its accumulated saving should be compensated (in a leaky bucket fashion)
- *
* class_list_lock must have been acquired
*/
-void update_class_cputime(int this_cpu)
+void update_global_cvts(int this_cpu)
{
struct ckrm_cpu_class *clsptr;
- ckrm_lrq_t * lrq;
- CVT_t cur_cvt;
-
- /*
- * a class's local_cvt must not be significantly smaller than min_cvt
- * of active classes otherwise, it will starve other classes when it
- * is reactivated.
- *
- * Hence we keep all local_cvt's within a range of the min_cvt off
- * all active classes (approximated by the local_cvt of the currently
- * running class) and account for how many cycles where thus taken
- * from an inactive class building a savings (not to exceed a few seconds)
- * for a class to gradually make up upon reactivation, without
- * starvation of other classes.
- *
- */
- cur_cvt = get_local_cur_cvt(this_cpu);
+ struct ckrm_local_runqueue *class_queue;
- /*
- * cur_cvt == 0 means the system is now idle
- * in this case, we use max_cvt as cur_cvt
- * max_cvt roughly represents the cvt of the class
- * that has just finished running
- *
- * fairness wouldn't be a problem since we account for whatever lost in savings
- * if the system is not busy, the system responsiveness is not a problem.
- * still fine if the sytem is busy, but happened to be idle at this certain point
- * since bias toward interactive classes (class priority) is a more important way to improve system responsiveness
- */
- if (unlikely(! cur_cvt)) {
- cur_cvt = get_max_cvt(this_cpu);
- //return;
- }
-
- /*
- * - check the local cvt of all the classes
- * - update total_ns received by the class
- * - do a usage sampling for the whole class
- */
+ /*for each class*/
list_for_each_entry(clsptr, &active_cpu_classes, links) {
- lrq = get_ckrm_lrq(clsptr, this_cpu);
-
- spin_lock(&clsptr->stat.stat_lock);
- clsptr->stat.total_ns += lrq->uncounted_ns;
- ckrm_sample_usage(clsptr);
- spin_unlock(&clsptr->stat.stat_lock);
- lrq->uncounted_ns = 0;
-
- check_inactive_class(lrq,cur_cvt);
+ update_global_cvt(clsptr, this_cpu);
+ class_queue = get_ckrm_local_runqueue(clsptr, this_cpu);
+ clsptr->stat.total_ns += class_queue->uncounted_ns;
+ class_queue->uncounted_ns = 0;
}
}
-
-/*******************************************************/
-/* PID load balancing stuff */
-/*******************************************************/
-#define PID_SAMPLE_T 32
-#define PID_KP 20
-#define PID_KI 60
-#define PID_KD 20
-
-/**
- * sample pid load periodically
- */
-void ckrm_load_sample(ckrm_load_t* pid,int cpu)
-{
- long load;
- long err;
-
- if (jiffies % PID_SAMPLE_T)
- return;
-
- adjust_local_weight();
-
- load = ckrm_cpu_load(cpu);
- err = load - pid->load_p;
- pid->load_d = err;
- pid->load_p = load;
- pid->load_i *= 9;
- pid->load_i += load;
- pid->load_i /= 10;
-}
-
-long pid_get_pressure(ckrm_load_t* ckrm_load, int local_group)
-{
- long pressure;
- pressure = ckrm_load->load_p * PID_KP;
- pressure += ckrm_load->load_i * PID_KI;
- pressure += ckrm_load->load_d * PID_KD;
- pressure /= 100;
- return pressure;
-}
git://git.onelab.eu / linux-2.6.git / blobdiff