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

@@ -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);
}
/*