Commit 3e3e13f3 authored by Ingo Molnar's avatar Ingo Molnar
Browse files

sched: remove PREEMPT_RESTRICT 



remove PREEMPT_RESTRICT. (this is a separate commit so that any
regression related to the removal itself is bisectable)

Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 52d3da1a

include/linux/sched.h

+0 −1
Original line number Diff line number Diff line
@@ -863,7 +863,6 @@ struct sched_entity { 
	struct load_weight	load;		/* for load-balancing */

	struct rb_node		run_node;

	unsigned int		on_rq;

	int			peer_preempt;



	u64			exec_start;

	u64			sum_exec_runtime;

kernel/sched.c

+1 −3
Original line number Diff line number Diff line
@@ -460,7 +460,6 @@ enum { 
	SCHED_FEAT_TREE_AVG             = 4,

	SCHED_FEAT_APPROX_AVG           = 8,

	SCHED_FEAT_WAKEUP_PREEMPT	= 16,

	SCHED_FEAT_PREEMPT_RESTRICT	= 32,

};



const_debug unsigned int sysctl_sched_features =
@@ -468,8 +467,7 @@ const_debug unsigned int sysctl_sched_features = 
		SCHED_FEAT_START_DEBIT		* 1 |

		SCHED_FEAT_TREE_AVG		* 0 |

		SCHED_FEAT_APPROX_AVG		* 0 |

		SCHED_FEAT_WAKEUP_PREEMPT	* 1 |

		SCHED_FEAT_PREEMPT_RESTRICT	* 0;

		SCHED_FEAT_WAKEUP_PREEMPT	* 1;



#define sched_feat(x) (sysctl_sched_features & SCHED_FEAT_##x)

kernel/sched_fair.c

+2 −8
Original line number Diff line number Diff line
@@ -546,7 +546,6 @@ dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int sleep) 


	update_stats_dequeue(cfs_rq, se);

	if (sleep) {

		se->peer_preempt = 0;

#ifdef CONFIG_SCHEDSTATS

		if (entity_is_task(se)) {

			struct task_struct *tsk = task_of(se);
@@ -574,10 +573,8 @@ check_preempt_tick(struct cfs_rq *cfs_rq, struct sched_entity *curr) 


	ideal_runtime = sched_slice(cfs_rq, curr);

	delta_exec = curr->sum_exec_runtime - curr->prev_sum_exec_runtime;

	if (delta_exec > ideal_runtime ||

			(sched_feat(PREEMPT_RESTRICT) && curr->peer_preempt))

	if (delta_exec > ideal_runtime)

		resched_task(rq_of(cfs_rq)->curr);

	curr->peer_preempt = 0;

}



static void
@@ -867,9 +864,7 @@ static void check_preempt_wakeup(struct rq *rq, struct task_struct *p) 
			gran = calc_delta_fair(gran, &se->load);



		if (delta > gran) {

			int now = !sched_feat(PREEMPT_RESTRICT);



			if (now || p->prio < curr->prio || !se->peer_preempt++)

			if (p->prio < curr->prio)

				resched_task(curr);

		}

	}
@@ -1083,7 +1078,6 @@ static void task_new_fair(struct rq *rq, struct task_struct *p) 
		swap(curr->vruntime, se->vruntime);

	}



	se->peer_preempt = 0;

	enqueue_task_fair(rq, p, 0);

	resched_task(rq->curr);

}