Commit fad095a7 authored by Srivatsa Vaddagiri's avatar Srivatsa Vaddagiri Committed by Ingo Molnar
Browse files

sched: group scheduler, fix bloat 



Recent fix to check_preempt_wakeup() to check for preemption at higher
levels caused a size bloat for !CONFIG_FAIR_GROUP_SCHED.

Fix the problem.

  42277   10598     320   53195    cfcb kernel/sched.o-before_this_patch
  42216   10598     320   53134    cf8e kernel/sched.o-after_this_patch

Signed-off-by: default avatarSrivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
Reviewed-by: default avatarThomas Gleixner <tglx@linutronix.de>
parent fb615581

kernel/sched_fair.c

+25 −18
Original line number Diff line number Diff line
@@ -652,15 +652,21 @@ static inline struct cfs_rq *cpu_cfs_rq(struct cfs_rq *cfs_rq, int this_cpu) 
#define for_each_leaf_cfs_rq(rq, cfs_rq) \

	list_for_each_entry(cfs_rq, &rq->leaf_cfs_rq_list, leaf_cfs_rq_list)



/* Do the two (enqueued) tasks belong to the same group ? */

static inline int is_same_group(struct task_struct *curr, struct task_struct *p)

/* Do the two (enqueued) entities belong to the same group ? */

static inline int

is_same_group(struct sched_entity *se, struct sched_entity *pse)

{

	if (curr->se.cfs_rq == p->se.cfs_rq)

	if (se->cfs_rq == pse->cfs_rq)

		return 1;



	return 0;

}



static inline struct sched_entity *parent_entity(struct sched_entity *se)

{

	return se->parent;

}



#else	/* CONFIG_FAIR_GROUP_SCHED */



#define for_each_sched_entity(se) \
@@ -693,11 +699,17 @@ static inline struct cfs_rq *cpu_cfs_rq(struct cfs_rq *cfs_rq, int this_cpu) 
#define for_each_leaf_cfs_rq(rq, cfs_rq) \

		for (cfs_rq = &rq->cfs; cfs_rq; cfs_rq = NULL)



static inline int is_same_group(struct task_struct *curr, struct task_struct *p)

static inline int

is_same_group(struct sched_entity *se, struct sched_entity *pse)

{

	return 1;

}



static inline struct sched_entity *parent_entity(struct sched_entity *se)

{

	return NULL;

}



#endif	/* CONFIG_FAIR_GROUP_SCHED */



/*
@@ -787,8 +799,9 @@ static void yield_task_fair(struct rq *rq) 
static void check_preempt_wakeup(struct rq *rq, struct task_struct *p)

{

	struct task_struct *curr = rq->curr;

	struct cfs_rq *cfs_rq = task_cfs_rq(curr), *pcfs_rq;

	struct cfs_rq *cfs_rq = task_cfs_rq(curr);

	struct sched_entity *se = &curr->se, *pse = &p->se;

	s64 delta;



	if (unlikely(rt_prio(p->prio))) {

		update_rq_clock(rq);
@@ -797,21 +810,15 @@ static void check_preempt_wakeup(struct rq *rq, struct task_struct *p) 
		return;

	}



	for_each_sched_entity(se) {

		cfs_rq = cfs_rq_of(se);

		pcfs_rq = cfs_rq_of(pse);

	while (!is_same_group(se, pse)) {

		se = parent_entity(se);

		pse = parent_entity(pse);

	}



		if (cfs_rq == pcfs_rq) {

			s64 delta = se->vruntime - pse->vruntime;

	delta = se->vruntime - pse->vruntime;



	if (delta > (s64)sysctl_sched_wakeup_granularity)

		resched_task(curr);

			break;

		}

#ifdef CONFIG_FAIR_GROUP_SCHED

		pse = pse->parent;

#endif

	}

}



static struct task_struct *pick_next_task_fair(struct rq *rq)

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