#define LOW_CREDIT(p) \
((p)->interactive_credit < -CREDIT_LIMIT)
-#ifdef CONFIG_CKRM_CPU_SCHEDULE
-/*
- * if belong to different class, compare class priority
- * otherwise compare task priority
- */
-#define TASK_PREEMPTS_CURR(p, rq) \
- ( ((p)->cpu_class != (rq)->curr->cpu_class) \
- && ((rq)->curr != (rq)->idle) && ((p) != (rq)->idle )) \
- ? class_preempts_curr((p),(rq)->curr) \
- : ((p)->prio < (rq)->curr->prio)
-#else
-#define TASK_PREEMPTS_CURR(p, rq) \
- ((p)->prio < (rq)->curr->prio)
-#endif
-
/*
* BASE_TIMESLICE scales user-nice values [ -20 ... 19 ]
* to time slice values.
((MAX_TIMESLICE - MIN_TIMESLICE) * \
(MAX_PRIO-1 - (p)->static_prio) / (MAX_USER_PRIO-1)))
-unsigned int task_timeslice(task_t *p)
+static unsigned int task_timeslice(task_t *p)
{
return BASE_TIMESLICE(p);
}
#define task_hot(p, now, sd) ((now) - (p)->timestamp < (sd)->cache_hot_time)
-/*
- * These are the runqueue data structures:
- */
-
-typedef struct runqueue runqueue_t;
-#include <linux/ckrm_classqueue.h>
-#include <linux/ckrm_sched.h>
-
-/*
- * This is the main, per-CPU runqueue data structure.
- *
- * Locking rule: those places that want to lock multiple runqueues
- * (such as the load balancing or the thread migration code), lock
- * acquire operations must be ordered by ascending &runqueue.
- */
-struct runqueue {
- spinlock_t lock;
-
- /*
- * nr_running and cpu_load should be in the same cacheline because
- * remote CPUs use both these fields when doing load calculation.
- */
- unsigned long nr_running;
-#if defined(CONFIG_SMP)
- unsigned long cpu_load;
-#endif
- unsigned long long nr_switches, nr_preempt;
- unsigned long expired_timestamp, nr_uninterruptible;
- unsigned long long timestamp_last_tick;
- task_t *curr, *idle;
- struct mm_struct *prev_mm;
-#ifdef CONFIG_CKRM_CPU_SCHEDULE
- struct classqueue_struct classqueue;
- ckrm_load_t ckrm_load;
-#else
- prio_array_t *active, *expired, arrays[2];
-#endif
- int best_expired_prio;
- atomic_t nr_iowait;
-
-#ifdef CONFIG_SMP
- struct sched_domain *sd;
-
- /* For active balancing */
- int active_balance;
- int push_cpu;
-
- task_t *migration_thread;
- struct list_head migration_queue;
-#endif
-
-#ifdef CONFIG_VSERVER_HARDCPU
- struct list_head hold_queue;
- int idle_tokens;
-#endif
-};
-
-static DEFINE_PER_CPU(struct runqueue, runqueues);
+DEFINE_PER_CPU(struct runqueue, runqueues);
#define for_each_domain(cpu, domain) \
for (domain = cpu_rq(cpu)->sd; domain; domain = domain->parent)
# define task_running(rq, p) ((rq)->curr == (p))
#endif
+#ifdef CONFIG_CKRM_CPU_SCHEDULE
+#include <linux/ckrm_sched.h>
+spinlock_t cvt_lock = SPIN_LOCK_UNLOCKED;
+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;
+
/*
- * task_rq_lock - lock the runqueue a given task resides on and disable
- * interrupts. Note the ordering: we can safely lookup the task_rq without
- * explicitly disabling preemption.
+ * the minimum CVT allowed is the base_cvt
+ * otherwise, it will starve others
*/
-static runqueue_t *task_rq_lock(task_t *p, unsigned long *flags)
+CVT_t get_min_cvt(int cpu)
{
- struct runqueue *rq;
-
-repeat_lock_task:
- local_irq_save(*flags);
- rq = task_rq(p);
- spin_lock(&rq->lock);
- if (unlikely(rq != task_rq(p))) {
- spin_unlock_irqrestore(&rq->lock, *flags);
- goto repeat_lock_task;
- }
- return rq;
-}
+ cq_node_t *node;
+ struct ckrm_local_runqueue * lrq;
+ CVT_t min_cvt;
-static inline void task_rq_unlock(runqueue_t *rq, unsigned long *flags)
-{
- spin_unlock_irqrestore(&rq->lock, *flags);
+ node = classqueue_get_head(bpt_queue(cpu));
+ lrq = (node) ? class_list_entry(node) : NULL;
+
+ if (lrq)
+ min_cvt = lrq->local_cvt;
+ else
+ min_cvt = 0;
+
+ return min_cvt;
}
/*
- * rq_lock - lock a given runqueue and disable interrupts.
+ * update the classueue base for all the runqueues
+ * TODO: we can only update half of the min_base to solve the movebackward issue
*/
-static runqueue_t *this_rq_lock(void)
-{
- runqueue_t *rq;
+static inline void check_update_class_base(int this_cpu) {
+ unsigned long min_base = 0xFFFFFFFF;
+ cq_node_t *node;
+ int i;
- local_irq_disable();
- rq = this_rq();
- spin_lock(&rq->lock);
+ if (! cpu_online(this_cpu)) return;
- return rq;
+ /*
+ * find the min_base across all the processors
+ */
+ for_each_online_cpu(i) {
+ /*
+ * I should change it to directly use bpt->base
+ */
+ node = classqueue_get_head(bpt_queue(i));
+ if (node && node->prio < min_base) {
+ min_base = node->prio;
+ }
+ }
+ if (min_base != 0xFFFFFFFF)
+ classqueue_update_base(bpt_queue(this_cpu),min_base);
}
-static inline void rq_unlock(runqueue_t *rq)
+static inline void ckrm_rebalance_tick(int j,int this_cpu)
{
- spin_unlock_irq(&rq->lock);
+#ifdef CONFIG_CKRM_CPU_SCHEDULE
+ read_lock(&class_list_lock);
+ if (!(j % CVT_UPDATE_TICK))
+ update_global_cvts(this_cpu);
+
+#define CKRM_BASE_UPDATE_RATE 400
+ if (! (jiffies % CKRM_BASE_UPDATE_RATE))
+ check_update_class_base(this_cpu);
+
+ read_unlock(&class_list_lock);
+#endif
}
-#ifdef CONFIG_CKRM_CPU_SCHEDULE
-static inline ckrm_lrq_t *rq_get_next_class(struct runqueue *rq)
+static inline struct ckrm_local_runqueue *rq_get_next_class(struct runqueue *rq)
{
cq_node_t *node = classqueue_get_head(&rq->classqueue);
return ((node) ? class_list_entry(node) : NULL);
}
-/*
- * return the cvt of the current running class
- * if no current running class, return 0
- * assume cpu is valid (cpu_online(cpu) == 1)
- */
-CVT_t get_local_cur_cvt(int cpu)
-{
- ckrm_lrq_t * lrq = rq_get_next_class(cpu_rq(cpu));
-
- if (lrq)
- return lrq->local_cvt;
- else
- return 0;
-}
-
static inline struct task_struct * rq_get_next_task(struct runqueue* rq)
{
prio_array_t *array;
struct task_struct *next;
- ckrm_lrq_t *queue;
- int idx;
+ struct ckrm_local_runqueue *queue;
int cpu = smp_processor_id();
-
- // it is guaranteed be the ( rq->nr_running > 0 ) check in
- // schedule that a task will be found.
-
+
+ next = rq->idle;
retry_next_class:
- queue = rq_get_next_class(rq);
- // BUG_ON( !queue );
-
- array = queue->active;
- if (unlikely(!array->nr_active)) {
- queue->active = queue->expired;
- queue->expired = array;
- queue->expired_timestamp = 0;
+ if ((queue = rq_get_next_class(rq))) {
+ array = queue->active;
+ //check switch active/expired queue
+ if (unlikely(!queue->active->nr_active)) {
+ queue->active = queue->expired;
+ queue->expired = array;
+ queue->expired_timestamp = 0;
+
+ if (queue->active->nr_active)
+ set_top_priority(queue,
+ find_first_bit(queue->active->bitmap, MAX_PRIO));
+ else {
+ classqueue_dequeue(queue->classqueue,
+ &queue->classqueue_linkobj);
+ cpu_demand_event(get_rq_local_stat(queue,cpu),CPU_DEMAND_DEQUEUE,0);
+ }
- if (queue->active->nr_active)
- set_top_priority(queue,
- find_first_bit(queue->active->bitmap, MAX_PRIO));
- else {
- classqueue_dequeue(queue->classqueue,
- &queue->classqueue_linkobj);
- cpu_demand_event(get_rq_local_stat(queue,cpu),CPU_DEMAND_DEQUEUE,0);
+ goto retry_next_class;
}
- goto retry_next_class;
+ BUG_ON(!queue->active->nr_active);
+ next = task_list_entry(array->queue[queue->top_priority].next);
}
- // BUG_ON(!array->nr_active);
-
- idx = queue->top_priority;
- // BUG_ON (idx == MAX_PRIO);
- next = task_list_entry(array->queue[idx].next);
return next;
}
-#else /*! CONFIG_CKRM_CPU_SCHEDULE*/
+
+static inline void rq_load_inc(runqueue_t *rq, struct task_struct *p) { rq->ckrm_cpu_load += cpu_class_weight(p->cpu_class); }
+static inline void rq_load_dec(runqueue_t *rq, struct task_struct *p) { rq->ckrm_cpu_load -= cpu_class_weight(p->cpu_class); }
+
+#else /*CONFIG_CKRM_CPU_SCHEDULE*/
+
static inline struct task_struct * rq_get_next_task(struct runqueue* rq)
{
prio_array_t *array;
static inline void class_enqueue_task(struct task_struct* p, prio_array_t *array) { }
static inline void class_dequeue_task(struct task_struct* p, prio_array_t *array) { }
static inline void init_cpu_classes(void) { }
-#define rq_ckrm_load(rq) NULL
-static inline void ckrm_sched_tick(int j,int this_cpu,void* name) {}
+static inline void rq_load_inc(runqueue_t *rq, struct task_struct *p) { }
+static inline void rq_load_dec(runqueue_t *rq, struct task_struct *p) { }
#endif /* CONFIG_CKRM_CPU_SCHEDULE */
+
+/*
+ * task_rq_lock - lock the runqueue a given task resides on and disable
+ * interrupts. Note the ordering: we can safely lookup the task_rq without
+ * explicitly disabling preemption.
+ */
+runqueue_t *task_rq_lock(task_t *p, unsigned long *flags)
+{
+ struct runqueue *rq;
+
+repeat_lock_task:
+ local_irq_save(*flags);
+ rq = task_rq(p);
+ spin_lock(&rq->lock);
+ if (unlikely(rq != task_rq(p))) {
+ spin_unlock_irqrestore(&rq->lock, *flags);
+ goto repeat_lock_task;
+ }
+ return rq;
+}
+
+void task_rq_unlock(runqueue_t *rq, unsigned long *flags)
+{
+ spin_unlock_irqrestore(&rq->lock, *flags);
+}
+
+/*
+ * rq_lock - lock a given runqueue and disable interrupts.
+ */
+static runqueue_t *this_rq_lock(void)
+{
+ runqueue_t *rq;
+
+ local_irq_disable();
+ rq = this_rq();
+ spin_lock(&rq->lock);
+
+ return rq;
+}
+
+static inline void rq_unlock(runqueue_t *rq)
+{
+ spin_unlock_irq(&rq->lock);
+}
+
/*
* Adding/removing a task to/from a priority array:
*/
-static void dequeue_task(struct task_struct *p, prio_array_t *array)
+void dequeue_task(struct task_struct *p, prio_array_t *array)
{
+ BUG_ON(! array);
array->nr_active--;
list_del(&p->run_list);
if (list_empty(array->queue + p->prio))
class_dequeue_task(p,array);
}
-static void enqueue_task(struct task_struct *p, prio_array_t *array)
+void enqueue_task(struct task_struct *p, prio_array_t *array)
{
list_add_tail(&p->run_list, array->queue + p->prio);
__set_bit(p->prio, array->bitmap);
{
enqueue_task(p, rq_active(p,rq));
rq->nr_running++;
+ rq_load_inc(rq,p);
}
/*
{
enqueue_task_head(p, rq_active(p,rq));
rq->nr_running++;
+ rq_load_inc(rq,p);
}
static void recalc_task_prio(task_t *p, unsigned long long now)
static void deactivate_task(struct task_struct *p, runqueue_t *rq)
{
rq->nr_running--;
+ rq_load_dec(rq,p);
if (p->state == TASK_UNINTERRUPTIBLE)
rq->nr_uninterruptible++;
dequeue_task(p, p->array);
INIT_LIST_HEAD(&p->run_list);
p->array = NULL;
spin_lock_init(&p->switch_lock);
-#ifdef CONFIG_CKRM_CPU_SCHEDULE
- cpu_demand_event(&p->demand_stat,CPU_DEMAND_INIT,0);
-#endif
-
#ifdef CONFIG_PREEMPT
/*
* During context-switch we hold precisely one spinlock, which
p->array = current->array;
p->array->nr_active++;
rq->nr_running++;
- class_enqueue_task(p,p->array);
+ rq_load_inc(rq,p);
}
task_rq_unlock(rq, &flags);
}
{
unsigned long i, sum = 0;
- for_each_cpu(i)
+ for_each_online_cpu(i)
sum += cpu_rq(i)->nr_uninterruptible;
return sum;
{
unsigned long long i, sum = 0;
- for_each_cpu(i)
+ for_each_online_cpu(i)
sum += cpu_rq(i)->nr_switches;
return sum;
{
unsigned long i, sum = 0;
- for_each_cpu(i)
+ for_each_online_cpu(i)
sum += atomic_read(&cpu_rq(i)->nr_iowait);
return sum;
p->array = current->array;
p->array->nr_active++;
rq->nr_running++;
- class_enqueue_task(p,p->array);
+ rq_load_inc(rq,p);
}
} else {
/* Not the local CPU - must adjust timestamp */
{
dequeue_task(p, src_array);
src_rq->nr_running--;
+ rq_load_dec(src_rq,p);
+
set_task_cpu(p, this_cpu);
this_rq->nr_running++;
+ rq_load_inc(this_rq,p);
enqueue_task(p, this_array);
+
p->timestamp = (p->timestamp - src_rq->timestamp_last_tick)
+ this_rq->timestamp_last_tick;
/*
}
#ifdef CONFIG_CKRM_CPU_SCHEDULE
-static inline int ckrm_preferred_task(task_t *tmp,long min, long max,
- int phase, enum idle_type idle)
+
+struct ckrm_cpu_class *find_unbalanced_class(int busiest_cpu, int this_cpu, unsigned long *cls_imbalance)
{
- long pressure = task_load(tmp);
-
- if (pressure > max)
- return 0;
+ struct ckrm_cpu_class *most_unbalanced_class = NULL;
+ struct ckrm_cpu_class *clsptr;
+ int max_unbalance = 0;
- if ((idle == NOT_IDLE) && ! phase && (pressure <= min))
- return 0;
- return 1;
+ list_for_each_entry(clsptr,&active_cpu_classes,links) {
+ struct ckrm_local_runqueue *this_lrq = get_ckrm_local_runqueue(clsptr,this_cpu);
+ struct ckrm_local_runqueue *busiest_lrq = get_ckrm_local_runqueue(clsptr,busiest_cpu);
+ int unbalance_degree;
+
+ unbalance_degree = (local_queue_nr_running(busiest_lrq) - local_queue_nr_running(this_lrq)) * cpu_class_weight(clsptr);
+ if (unbalance_degree >= *cls_imbalance)
+ continue; // already looked at this class
+
+ if (unbalance_degree > max_unbalance) {
+ max_unbalance = unbalance_degree;
+ most_unbalanced_class = clsptr;
+ }
+ }
+ *cls_imbalance = max_unbalance;
+ return most_unbalanced_class;
}
+
/*
- * move tasks for a specic local class
- * return number of tasks pulled
+ * find_busiest_queue - find the busiest runqueue among the cpus in cpumask.
*/
-static inline int ckrm_cls_move_tasks(ckrm_lrq_t* src_lrq,ckrm_lrq_t*dst_lrq,
- runqueue_t *this_rq,
- runqueue_t *busiest,
- struct sched_domain *sd,
- int this_cpu,
- enum idle_type idle,
- long* pressure_imbalance)
+static int find_busiest_cpu(runqueue_t *this_rq, int this_cpu, int idle,
+ int *imbalance)
{
- prio_array_t *array, *dst_array;
+ int cpu_load, load, max_load, i, busiest_cpu;
+ runqueue_t *busiest, *rq_src;
+
+
+ /*Hubertus ... the concept of nr_running is replace with cpu_load */
+ cpu_load = this_rq->ckrm_cpu_load;
+
+ busiest = NULL;
+ busiest_cpu = -1;
+
+ max_load = -1;
+ for_each_online_cpu(i) {
+ rq_src = cpu_rq(i);
+ load = rq_src->ckrm_cpu_load;
+
+ if ((load > max_load) && (rq_src != this_rq)) {
+ busiest = rq_src;
+ busiest_cpu = i;
+ max_load = load;
+ }
+ }
+
+ if (likely(!busiest))
+ goto out;
+
+ *imbalance = max_load - cpu_load;
+
+ /* It needs an at least ~25% imbalance to trigger balancing. */
+ if (!idle && ((*imbalance)*4 < max_load)) {
+ busiest = NULL;
+ goto out;
+ }
+
+ double_lock_balance(this_rq, busiest);
+ /*
+ * Make sure nothing changed since we checked the
+ * runqueue length.
+ */
+ if (busiest->ckrm_cpu_load <= cpu_load) {
+ spin_unlock(&busiest->lock);
+ busiest = NULL;
+ }
+out:
+ return (busiest ? busiest_cpu : -1);
+}
+
+static int load_balance(int this_cpu, runqueue_t *this_rq,
+ struct sched_domain *sd, enum idle_type idle)
+{
+ int imbalance, idx;
+ int busiest_cpu;
+ runqueue_t *busiest;
+ prio_array_t *array;
struct list_head *head, *curr;
task_t *tmp;
- int idx;
- int pulled = 0;
- int phase = -1;
- long pressure_min, pressure_max;
- /*hzheng: magic : 90% balance is enough*/
- long balance_min = *pressure_imbalance / 10;
-/*
- * we don't want to migrate tasks that will reverse the balance
- * or the tasks that make too small difference
- */
-#define CKRM_BALANCE_MAX_RATIO 100
-#define CKRM_BALANCE_MIN_RATIO 1
- start:
- phase ++;
+ struct ckrm_local_runqueue * busiest_local_queue;
+ struct ckrm_cpu_class *clsptr;
+ int weight;
+ unsigned long cls_imbalance; // so we can retry other classes
+
+ // need to update global CVT based on local accumulated CVTs
+ read_lock(&class_list_lock);
+ busiest_cpu = find_busiest_cpu(this_rq, this_cpu, idle, &imbalance);
+ if (busiest_cpu == -1)
+ goto out;
+
+ busiest = cpu_rq(busiest_cpu);
+
+ /*
+ * We only want to steal a number of tasks equal to 1/2 the imbalance,
+ * otherwise we'll just shift the imbalance to the new queue:
+ */
+ imbalance /= 2;
+
+ /* now find class on that runqueue with largest inbalance */
+ cls_imbalance = 0xFFFFFFFF;
+
+ retry_other_class:
+ clsptr = find_unbalanced_class(busiest_cpu, this_cpu, &cls_imbalance);
+ if (!clsptr)
+ goto out_unlock;
+
+ busiest_local_queue = get_ckrm_local_runqueue(clsptr,busiest_cpu);
+ weight = cpu_class_weight(clsptr);
+
/*
* We first consider expired tasks. Those will likely not be
* executed in the near future, and they are most likely to
* be cache-cold, thus switching CPUs has the least effect
* on them.
*/
- if (src_lrq->expired->nr_active) {
- array = src_lrq->expired;
- dst_array = dst_lrq->expired;
- } else {
- array = src_lrq->active;
- dst_array = dst_lrq->active;
- }
+ if (busiest_local_queue->expired->nr_active)
+ array = busiest_local_queue->expired;
+ else
+ array = busiest_local_queue->active;
new_array:
/* Start searching at priority 0: */
else
idx = find_next_bit(array->bitmap, MAX_PRIO, idx);
if (idx >= MAX_PRIO) {
- if (array == src_lrq->expired && src_lrq->active->nr_active) {
- array = src_lrq->active;
- dst_array = dst_lrq->active;
+ if (array == busiest_local_queue->expired && busiest_local_queue->active->nr_active) {
+ array = busiest_local_queue->active;
goto new_array;
}
- if ((! phase) && (! pulled) && (idle != IDLE))
- goto start; //try again
- else
- goto out; //finished search for this lrq
+ goto retry_other_class;
}
head = array->queue + idx;
curr = curr->prev;
- if (!can_migrate_task(tmp, busiest, this_cpu, sd, idle)) {
+ if (!can_migrate_task(tmp, busiest, this_cpu, sd,idle)) {
if (curr != head)
goto skip_queue;
idx++;
goto skip_bitmap;
}
-
- pressure_min = *pressure_imbalance * CKRM_BALANCE_MIN_RATIO/100;
- pressure_max = *pressure_imbalance * CKRM_BALANCE_MAX_RATIO/100;
+ pull_task(busiest, array, tmp, this_rq, rq_active(tmp,this_rq),this_cpu);
/*
- * skip the tasks that will reverse the balance too much
+ * tmp BUG FIX: hzheng
+ * load balancing can make the busiest local queue empty
+ * thus it should be removed from bpt
*/
- if (ckrm_preferred_task(tmp,pressure_min,pressure_max,phase,idle)) {
- *pressure_imbalance -= task_load(tmp);
- pull_task(busiest, array, tmp,
- this_rq, dst_array, this_cpu);
- pulled++;
-
- if (*pressure_imbalance <= balance_min)
- goto out;
+ if (! local_queue_nr_running(busiest_local_queue)) {
+ classqueue_dequeue(busiest_local_queue->classqueue,&busiest_local_queue->classqueue_linkobj);
+ cpu_demand_event(get_rq_local_stat(busiest_local_queue,busiest_cpu),CPU_DEMAND_DEQUEUE,0);
}
-
- if (curr != head)
- goto skip_queue;
- idx++;
- goto skip_bitmap;
- out:
- return pulled;
-}
-
-static inline long ckrm_rq_imbalance(runqueue_t *this_rq,runqueue_t *dst_rq)
-{
- long imbalance;
- /*
- * make sure after balance, imbalance' > - imbalance/2
- * we don't want the imbalance be reversed too much
- */
- imbalance = pid_get_pressure(rq_ckrm_load(dst_rq),0)
- - pid_get_pressure(rq_ckrm_load(this_rq),1);
- imbalance /= 2;
- return imbalance;
-}
-
-/*
- * try to balance the two runqueues
- *
- * Called with both runqueues locked.
- * if move_tasks is called, it will try to move at least one task over
- */
-static int move_tasks(runqueue_t *this_rq, int this_cpu, runqueue_t *busiest,
- unsigned long max_nr_move, struct sched_domain *sd,
- enum idle_type idle)
-{
- struct ckrm_cpu_class *clsptr,*vip_cls = NULL;
- ckrm_lrq_t* src_lrq,*dst_lrq;
- long pressure_imbalance, pressure_imbalance_old;
- int src_cpu = task_cpu(busiest->curr);
- struct list_head *list;
- int pulled = 0;
- long imbalance;
- imbalance = ckrm_rq_imbalance(this_rq,busiest);
-
- if ((idle == NOT_IDLE && imbalance <= 0) || busiest->nr_running <= 1)
- goto out;
-
- //try to find the vip class
- list_for_each_entry(clsptr,&active_cpu_classes,links) {
- src_lrq = get_ckrm_lrq(clsptr,src_cpu);
-
- if (! lrq_nr_running(src_lrq))
- continue;
-
- if (! vip_cls || cpu_class_weight(vip_cls) < cpu_class_weight(clsptr) )
- {
- vip_cls = clsptr;
- }
+ imbalance -= weight;
+ if (!idle && (imbalance>0)) {
+ if (curr != head)
+ goto skip_queue;
+ idx++;
+ goto skip_bitmap;
}
-
- /*
- * do search from the most significant class
- * hopefully, less tasks will be migrated this way
- */
- clsptr = vip_cls;
-
- move_class:
- if (! clsptr)
- goto out;
-
-
- src_lrq = get_ckrm_lrq(clsptr,src_cpu);
- if (! lrq_nr_running(src_lrq))
- goto other_class;
-
- dst_lrq = get_ckrm_lrq(clsptr,this_cpu);
-
- //how much pressure for this class should be transferred
- pressure_imbalance = src_lrq->lrq_load * imbalance/src_lrq->local_weight;
- if (pulled && ! pressure_imbalance)
- goto other_class;
-
- pressure_imbalance_old = pressure_imbalance;
-
- //move tasks
- pulled +=
- ckrm_cls_move_tasks(src_lrq,dst_lrq,
- this_rq,
- busiest,
- sd,this_cpu,idle,
- &pressure_imbalance);
-
- /*
- * hzheng: 2 is another magic number
- * stop balancing if the imbalance is less than 25% of the orig
- */
- if (pressure_imbalance <= (pressure_imbalance_old >> 2))
- goto out;
-
- //update imbalance
- imbalance *= pressure_imbalance / pressure_imbalance_old;
- other_class:
- //who is next?
- list = clsptr->links.next;
- if (list == &active_cpu_classes)
- list = list->next;
- clsptr = list_entry(list, typeof(*clsptr), links);
- if (clsptr != vip_cls)
- goto move_class;
+ out_unlock:
+ spin_unlock(&busiest->lock);
out:
- return pulled;
-}
-
-/**
- * ckrm_check_balance - is load balancing necessary?
- * return 0 if load balancing is not necessary
- * otherwise return the average load of the system
- * also, update nr_group
- *
- * heuristics:
- * no load balancing if it's load is over average
- * no load balancing if it's load is far more than the min
- * task:
- * read the status of all the runqueues
- */
-static unsigned long ckrm_check_balance(struct sched_domain *sd, int this_cpu,
- enum idle_type idle, int* nr_group)
-{
- struct sched_group *group = sd->groups;
- unsigned long min_load, max_load, avg_load;
- unsigned long total_load, this_load, total_pwr;
-
- max_load = this_load = total_load = total_pwr = 0;
- min_load = 0xFFFFFFFF;
- *nr_group = 0;
-
- do {
- cpumask_t tmp;
- unsigned long load;
- int local_group;
- int i, nr_cpus = 0;
-
- /* Tally up the load of all CPUs in the group */
- cpus_and(tmp, group->cpumask, cpu_online_map);
- if (unlikely(cpus_empty(tmp)))
- goto nextgroup;
-
- avg_load = 0;
- local_group = cpu_isset(this_cpu, group->cpumask);
-
- for_each_cpu_mask(i, tmp) {
- load = pid_get_pressure(rq_ckrm_load(cpu_rq(i)),local_group);
- nr_cpus++;
- avg_load += load;
- }
-
- if (!nr_cpus)
- goto nextgroup;
-
- total_load += avg_load;
- total_pwr += group->cpu_power;
-
- /* Adjust by relative CPU power of the group */
- avg_load = (avg_load * SCHED_LOAD_SCALE) / group->cpu_power;
-
- if (local_group) {
- this_load = avg_load;
- goto nextgroup;
- } else if (avg_load > max_load) {
- max_load = avg_load;
- }
- if (avg_load < min_load) {
- min_load = avg_load;
- }
-nextgroup:
- group = group->next;
- *nr_group = *nr_group + 1;
- } while (group != sd->groups);
-
- if (!max_load || this_load >= max_load)
- goto out_balanced;
-
- avg_load = (SCHED_LOAD_SCALE * total_load) / total_pwr;
-
- /* hzheng: debugging: 105 is a magic number
- * 100*max_load <= sd->imbalance_pct*this_load)
- * should use imbalance_pct instead
- */
- if (this_load > avg_load
- || 100*max_load < 105*this_load
- || 100*min_load < 70*this_load
- )
- goto out_balanced;
-
- return avg_load;
- out_balanced:
- return 0;
-}
-
-/**
- * any group that has above average load is considered busy
- * find the busiest queue from any of busy group
- */
-static runqueue_t *
-ckrm_find_busy_queue(struct sched_domain *sd, int this_cpu,
- unsigned long avg_load, enum idle_type idle,
- int nr_group)
-{
- struct sched_group *group;
- runqueue_t * busiest=NULL;
- unsigned long rand;
-
- group = sd->groups;
- rand = get_ckrm_rand(nr_group);
- nr_group = 0;
-
- do {
- unsigned long load,total_load,max_load;
- cpumask_t tmp;
- int i;
- runqueue_t * grp_busiest;
-
- cpus_and(tmp, group->cpumask, cpu_online_map);
- if (unlikely(cpus_empty(tmp)))
- goto find_nextgroup;
-
- total_load = 0;
- max_load = 0;
- grp_busiest = NULL;
- for_each_cpu_mask(i, tmp) {
- load = pid_get_pressure(rq_ckrm_load(cpu_rq(i)),0);
- total_load += load;
- if (load > max_load) {
- max_load = load;
- grp_busiest = cpu_rq(i);
- }
- }
-
- total_load = (total_load * SCHED_LOAD_SCALE) / group->cpu_power;
- if (total_load > avg_load) {
- busiest = grp_busiest;
- if (nr_group >= rand)
- break;
- }
- find_nextgroup:
- group = group->next;
- nr_group ++;
- } while (group != sd->groups);
-
- return busiest;
-}
-
-/**
- * load_balance - pressure based load balancing algorithm used by ckrm
- */
-static int ckrm_load_balance(int this_cpu, runqueue_t *this_rq,
- struct sched_domain *sd, enum idle_type idle)
-{
- runqueue_t *busiest;
- unsigned long avg_load;
- int nr_moved,nr_group;
-
- avg_load = ckrm_check_balance(sd, this_cpu, idle, &nr_group);
- if (! avg_load)
- goto out_balanced;
-
- busiest = ckrm_find_busy_queue(sd,this_cpu,avg_load,idle,nr_group);
- if (! busiest)
- goto out_balanced;
- /*
- * This should be "impossible", but since load
- * balancing is inherently racy and statistical,
- * it could happen in theory.
- */
- if (unlikely(busiest == this_rq)) {
- WARN_ON(1);
- goto out_balanced;
- }
-
- nr_moved = 0;
- if (busiest->nr_running > 1) {
- /*
- * Attempt to move tasks. If find_busiest_group has found
- * an imbalance but busiest->nr_running <= 1, the group is
- * still unbalanced. nr_moved simply stays zero, so it is
- * correctly treated as an imbalance.
- */
- double_lock_balance(this_rq, busiest);
- nr_moved = move_tasks(this_rq, this_cpu, busiest,
- 0,sd, idle);
- spin_unlock(&busiest->lock);
- if (nr_moved) {
- adjust_local_weight();
- }
- }
-
- if (!nr_moved)
- sd->nr_balance_failed ++;
- else
- sd->nr_balance_failed = 0;
-
- /* We were unbalanced, so reset the balancing interval */
- sd->balance_interval = sd->min_interval;
-
- return nr_moved;
-
-out_balanced:
- /* tune up the balancing interval */
- if (sd->balance_interval < sd->max_interval)
- sd->balance_interval *= 2;
-
+ read_unlock(&class_list_lock);
return 0;
}
-/*
- * this_rq->lock is already held
- */
-static inline int load_balance_newidle(int this_cpu, runqueue_t *this_rq,
- struct sched_domain *sd)
-{
- int ret;
- read_lock(&class_list_lock);
- ret = ckrm_load_balance(this_cpu,this_rq,sd,NEWLY_IDLE);
- read_unlock(&class_list_lock);
- return ret;
-}
-static inline int load_balance(int this_cpu, runqueue_t *this_rq,
- struct sched_domain *sd, enum idle_type idle)
+static inline void idle_balance(int this_cpu, runqueue_t *this_rq)
{
- int ret;
-
- spin_lock(&this_rq->lock);
- read_lock(&class_list_lock);
- ret= ckrm_load_balance(this_cpu,this_rq,sd,NEWLY_IDLE);
- read_unlock(&class_list_lock);
- spin_unlock(&this_rq->lock);
- return ret;
}
-#else /*! CONFIG_CKRM_CPU_SCHEDULE */
+#else /* CONFIG_CKRM_CPU_SCHEDULE */
/*
* move_tasks tries to move up to max_nr_move tasks from busiest to this_rq,
* as part of a balancing operation within "domain". Returns the number of
out:
return nr_moved;
}
-#endif /* CONFIG_CKRM_CPU_SCHEDULE*/
-
/*
* idle_balance is called by schedule() if this_cpu is about to become
group = group->next;
} while (group != sd->groups);
}
+#endif /* CONFIG_CKRM_CPU_SCHEDULE*/
/*
* rebalance_tick will get called every timer tick, on every CPU.
unsigned long j = jiffies + CPU_OFFSET(this_cpu);
struct sched_domain *sd;
+ ckrm_rebalance_tick(j,this_cpu);
+
/* Update our load */
old_load = this_rq->cpu_load;
this_load = this_rq->nr_running * SCHED_LOAD_SCALE;
*/
static inline void rebalance_tick(int cpu, runqueue_t *rq, enum idle_type idle)
{
+ ckrm_rebalance_tick(jiffies,cpu);
}
+
static inline void idle_balance(int cpu, runqueue_t *rq)
{
}
return 0;
}
-DEFINE_PER_CPU(struct kernel_stat, kstat);
+DEFINE_PER_CPU(struct kernel_stat, kstat) = { { 0 } };
+
EXPORT_PER_CPU_SYMBOL(kstat);
/*
#define EXPIRED_STARVING(rq) \
(STARVATION_LIMIT && ((rq)->expired_timestamp && \
(jiffies - (rq)->expired_timestamp >= \
- STARVATION_LIMIT * (lrq_nr_running(rq)) + 1)))
+ STARVATION_LIMIT * (local_queue_nr_running(rq)) + 1)))
#endif
/*
}
if (p == rq->idle) {
-#ifdef CONFIG_VSERVER_HARDCPU
if (!--rq->idle_tokens && !list_empty(&rq->hold_queue))
set_need_resched();
-#endif
if (atomic_read(&rq->nr_iowait) > 0)
cpustat->iowait += sys_ticks;
cpustat->idle += sys_ticks;
if (wake_priority_sleeper(rq))
goto out;
- ckrm_sched_tick(jiffies,cpu,rq_ckrm_load(rq));
rebalance_tick(cpu, rq, IDLE);
return;
}
}
goto out_unlock;
}
+#warning MEF PLANETLAB: "if (vx_need_resched(p)) was if (!--p->time_slice) */"
if (vx_need_resched(p)) {
#ifdef CONFIG_CKRM_CPU_SCHEDULE
/* Hubertus ... we can abstract this out */
- ckrm_lrq_t* rq = get_task_lrq(p);
+ struct ckrm_local_runqueue* rq = get_task_class_queue(p);
#endif
dequeue_task(p, rq->active);
set_tsk_need_resched(p);
out_unlock:
spin_unlock(&rq->lock);
out:
- ckrm_sched_tick(jiffies,cpu,rq_ckrm_load(rq));
rebalance_tick(cpu, rq, NOT_IDLE);
}
spin_lock_irq(&rq->lock);
-#ifdef CONFIG_CKRM_CPU_SCHEDULE
- if (prev != rq->idle) {
- unsigned long long run = now - prev->timestamp;
- ckrm_lrq_t * lrq = get_task_lrq(prev);
-
- lrq->lrq_load -= task_load(prev);
- cpu_demand_event(&prev->demand_stat,CPU_DEMAND_DESCHEDULE,run);
- lrq->lrq_load += task_load(prev);
-
- cpu_demand_event(get_task_lrq_stat(prev),CPU_DEMAND_DESCHEDULE,run);
- update_local_cvt(prev, run);
- }
-#endif
/*
* if entering off of a kernel preemption go straight
* to picking the next task.
#endif
if (unlikely(!rq->nr_running)) {
idle_balance(cpu, rq);
- if (!rq->nr_running) {
- next = rq->idle;
-#ifdef CONFIG_CKRM_CPU_SCHEDULE
- rq->expired_timestamp = 0;
-#endif
- wake_sleeping_dependent(cpu, rq);
- goto switch_tasks;
- }
+ if (!rq->nr_running) {
+ next = rq->idle;
+ rq->expired_timestamp = 0;
+ wake_sleeping_dependent(cpu, rq);
+ goto switch_tasks;
+ }
}
next = rq_get_next_task(rq);
+ if (next == rq->idle)
+ goto switch_tasks;
if (dependent_sleeper(cpu, rq, next)) {
next = rq->idle;
rq->nr_preempt++;
RCU_qsctr(task_cpu(prev))++;
+#ifdef CONFIG_CKRM_CPU_SCHEDULE
+ if (prev != rq->idle) {
+ unsigned long long run = now - prev->timestamp;
+ cpu_demand_event(get_task_local_stat(prev),CPU_DEMAND_DESCHEDULE,run);
+ update_local_cvt(prev, run);
+ }
+#endif
+
prev->sleep_avg -= run_time;
if ((long)prev->sleep_avg <= 0) {
prev->sleep_avg = 0;
}
EXPORT_SYMBOL(schedule);
+
#ifdef CONFIG_PREEMPT
/*
* this is is the entry point to schedule() from in-kernel preemption
if (!cpu_isset(dest_cpu, p->cpus_allowed))
goto out;
+ set_task_cpu(p, dest_cpu);
if (p->array) {
/*
* Sync timestamp with rq_dest's before activating.
p->timestamp = p->timestamp - rq_src->timestamp_last_tick
+ rq_dest->timestamp_last_tick;
deactivate_task(p, rq_src);
- set_task_cpu(p, dest_cpu);
activate_task(p, rq_dest, 0);
if (TASK_PREEMPTS_CURR(p, rq_dest))
resched_task(rq_dest->curr);
- } else
- set_task_cpu(p, dest_cpu);
+ }
out:
double_rq_unlock(rq_src, rq_dest);
}
if (rq->active_balance) {
+#ifndef CONFIG_CKRM_CPU_SCHEDULE
active_load_balance(rq, cpu);
+#endif
rq->active_balance = 0;
}
{
runqueue_t *rq;
int i;
+#ifndef CONFIG_CKRM_CPU_SCHEDULE
+ int j, k;
+#endif
#ifdef CONFIG_SMP
/* Set up an initial dummy domain for early boot */
sched_domain_init.groups = &sched_group_init;
sched_domain_init.last_balance = jiffies;
sched_domain_init.balance_interval = INT_MAX; /* Don't balance */
- sched_domain_init.busy_factor = 1;
memset(&sched_group_init, 0, sizeof(struct sched_group));
sched_group_init.cpumask = CPU_MASK_ALL;
sched_group_init.next = &sched_group_init;
sched_group_init.cpu_power = SCHED_LOAD_SCALE;
#endif
+
init_cpu_classes();
for (i = 0; i < NR_CPUS; i++) {
#ifndef CONFIG_CKRM_CPU_SCHEDULE
- int j, k;
prio_array_t *array;
-
+#endif
rq = cpu_rq(i);
spin_lock_init(&rq->lock);
- for (j = 0; j < 2; j++) {
- array = rq->arrays + j;
- for (k = 0; k < MAX_PRIO; k++) {
- INIT_LIST_HEAD(array->queue + k);
- __clear_bit(k, array->bitmap);
- }
- // delimiter for bitsearch
- __set_bit(MAX_PRIO, array->bitmap);
- }
-
+#ifndef CONFIG_CKRM_CPU_SCHEDULE
rq->active = rq->arrays;
rq->expired = rq->arrays + 1;
#else
- rq = cpu_rq(i);
- spin_lock_init(&rq->lock);
+ rq->ckrm_cpu_load = 0;
#endif
-
rq->best_expired_prio = MAX_PRIO;
#ifdef CONFIG_SMP
rq->sd = &sched_domain_init;
rq->cpu_load = 0;
-#ifdef CONFIG_CKRM_CPU_SCHEDULE
- ckrm_load_init(rq_ckrm_load(rq));
-#endif
rq->active_balance = 0;
rq->push_cpu = 0;
rq->migration_thread = NULL;
INIT_LIST_HEAD(&rq->migration_queue);
#endif
-#ifdef CONFIG_VSERVER_HARDCPU
INIT_LIST_HEAD(&rq->hold_queue);
-#endif
atomic_set(&rq->nr_iowait, 0);
+
+#ifndef CONFIG_CKRM_CPU_SCHEDULE
+ for (j = 0; j < 2; j++) {
+ array = rq->arrays + j;
+ for (k = 0; k < MAX_PRIO; k++) {
+ INIT_LIST_HEAD(array->queue + k);
+ __clear_bit(k, array->bitmap);
+ }
+ // delimiter for bitsearch
+ __set_bit(MAX_PRIO, array->bitmap);
+ }
+#endif
}
/*
rq->idle = current;
set_task_cpu(current, smp_processor_id());
#ifdef CONFIG_CKRM_CPU_SCHEDULE
- cpu_demand_event(&(current)->demand_stat,CPU_DEMAND_INIT,0);
- current->cpu_class = get_default_cpu_class();
+ current->cpu_class = default_cpu_class;
current->array = NULL;
#endif
wake_up_forked_process(current);
#ifdef CONFIG_CKRM_CPU_SCHEDULE
/**
* return the classqueue object of a certain processor
+ * Note: not supposed to be used in performance sensitive functions
*/
struct classqueue_struct * get_cpu_classqueue(int cpu)
{
return (& (cpu_rq(cpu)->classqueue) );
}
-
-/**
- * _ckrm_cpu_change_class - change the class of a task
- */
-void _ckrm_cpu_change_class(task_t *tsk, struct ckrm_cpu_class *newcls)
-{
- prio_array_t *array;
- struct runqueue *rq;
- unsigned long flags;
-
- rq = task_rq_lock(tsk,&flags);
- array = tsk->array;
- if (array) {
- dequeue_task(tsk,array);
- tsk->cpu_class = newcls;
- enqueue_task(tsk,rq_active(tsk,rq));
- } else
- tsk->cpu_class = newcls;
-
- task_rq_unlock(rq,&flags);
-}
#endif
git://git.onelab.eu / linux-2.6.git / blobdiff