sched: group scheduling, change how cpu load is calculated

This patch changes how the cpu load exerted by fair_sched_class tasks
is calculated. Load exerted by fair_sched_class tasks on a cpu is now
a summation of the group weights, rather than summation of task weights.
Weight exerted by a group on a cpu is dependent on the shares allocated
to it.

This version of patch has a minor impact on code size, but should have
no runtime/functional impact for !CONFIG_FAIR_GROUP_SCHED.

Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Srivatsa Vaddagiri 2008-01-25 21:08:00 +01:00 committed by Ingo Molnar
parent ec2c507fe8
commit 58e2d4ca58
3 changed files with 40 additions and 20 deletions

View file

@ -886,6 +886,16 @@ static void cpuacct_charge(struct task_struct *tsk, u64 cputime);
static inline void cpuacct_charge(struct task_struct *tsk, u64 cputime) {}
#endif
static inline void inc_cpu_load(struct rq *rq, unsigned long load)
{
update_load_add(&rq->load, load);
}
static inline void dec_cpu_load(struct rq *rq, unsigned long load)
{
update_load_sub(&rq->load, load);
}
#include "sched_stats.h"
#include "sched_idletask.c"
#include "sched_fair.c"
@ -896,26 +906,14 @@ static inline void cpuacct_charge(struct task_struct *tsk, u64 cputime) {}
#define sched_class_highest (&rt_sched_class)
static inline void inc_load(struct rq *rq, const struct task_struct *p)
{
update_load_add(&rq->load, p->se.load.weight);
}
static inline void dec_load(struct rq *rq, const struct task_struct *p)
{
update_load_sub(&rq->load, p->se.load.weight);
}
static void inc_nr_running(struct task_struct *p, struct rq *rq)
{
rq->nr_running++;
inc_load(rq, p);
}
static void dec_nr_running(struct task_struct *p, struct rq *rq)
{
rq->nr_running--;
dec_load(rq, p);
}
static void set_load_weight(struct task_struct *p)
@ -4087,10 +4085,8 @@ void set_user_nice(struct task_struct *p, long nice)
goto out_unlock;
}
on_rq = p->se.on_rq;
if (on_rq) {
if (on_rq)
dequeue_task(rq, p, 0);
dec_load(rq, p);
}
p->static_prio = NICE_TO_PRIO(nice);
set_load_weight(p);
@ -4100,7 +4096,6 @@ void set_user_nice(struct task_struct *p, long nice)
if (on_rq) {
enqueue_task(rq, p, 0);
inc_load(rq, p);
/*
* If the task increased its priority or is running and
* lowered its priority, then reschedule its CPU:

View file

@ -760,15 +760,26 @@ static inline struct sched_entity *parent_entity(struct sched_entity *se)
static void enqueue_task_fair(struct rq *rq, struct task_struct *p, int wakeup)
{
struct cfs_rq *cfs_rq;
struct sched_entity *se = &p->se;
struct sched_entity *se = &p->se,
*topse = NULL; /* Highest schedulable entity */
int incload = 1;
for_each_sched_entity(se) {
if (se->on_rq)
topse = se;
if (se->on_rq) {
incload = 0;
break;
}
cfs_rq = cfs_rq_of(se);
enqueue_entity(cfs_rq, se, wakeup);
wakeup = 1;
}
/* Increment cpu load if we just enqueued the first task of a group on
* 'rq->cpu'. 'topse' represents the group to which task 'p' belongs
* at the highest grouping level.
*/
if (incload)
inc_cpu_load(rq, topse->load.weight);
}
/*
@ -779,16 +790,28 @@ static void enqueue_task_fair(struct rq *rq, struct task_struct *p, int wakeup)
static void dequeue_task_fair(struct rq *rq, struct task_struct *p, int sleep)
{
struct cfs_rq *cfs_rq;
struct sched_entity *se = &p->se;
struct sched_entity *se = &p->se,
*topse = NULL; /* Highest schedulable entity */
int decload = 1;
for_each_sched_entity(se) {
topse = se;
cfs_rq = cfs_rq_of(se);
dequeue_entity(cfs_rq, se, sleep);
/* Don't dequeue parent if it has other entities besides us */
if (cfs_rq->load.weight)
if (cfs_rq->load.weight) {
if (parent_entity(se))
decload = 0;
break;
}
sleep = 1;
}
/* Decrement cpu load if we just dequeued the last task of a group on
* 'rq->cpu'. 'topse' represents the group to which task 'p' belongs
* at the highest grouping level.
*/
if (decload)
dec_cpu_load(rq, topse->load.weight);
}
/*

View file

@ -32,6 +32,7 @@ static void enqueue_task_rt(struct rq *rq, struct task_struct *p, int wakeup)
list_add_tail(&p->run_list, array->queue + p->prio);
__set_bit(p->prio, array->bitmap);
inc_cpu_load(rq, p->se.load.weight);
}
/*
@ -46,6 +47,7 @@ static void dequeue_task_rt(struct rq *rq, struct task_struct *p, int sleep)
list_del(&p->run_list);
if (list_empty(array->queue + p->prio))
__clear_bit(p->prio, array->bitmap);
dec_cpu_load(rq, p->se.load.weight);
}
/*