Commit b7772972 authored by Cheng Yu's avatar Cheng Yu
Browse files

sched/core: Add cpu.steal_task in cgroup v1 cpu subsystem 

hulk inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/IAQWPQ



-----------------------------------------

We add a new cpu.steal_task interface in cgroup v1 for a certain cgroup.
The default value is 0, which means it is disabled, and 1, which means
it is enabled.

If we want to enable the steal task feature for a cgroup, we first need
to configure group_steal in cmdline, then configure STEAL in
sched_feature, and finally configure the value of cpu.steal_task to 1.

Signed-off-by: default avatarCheng Yu <serein.chengyu@huawei.com>
parent c835db9d

include/linux/sched.h

+4 −0
Original line number Diff line number Diff line
@@ -522,7 +522,11 @@ struct sched_entity { 
#else

	KABI_RESERVE(1)

#endif

#ifdef CONFIG_SCHED_STEAL

	KABI_USE(2, int steal_task)

#else

	KABI_RESERVE(2)

#endif

	KABI_RESERVE(3)

	KABI_RESERVE(4)

};

kernel/sched/core.c

+108 −0
Original line number Diff line number Diff line
@@ -8275,6 +8275,9 @@ void __init sched_init(void) 
#ifdef CONFIG_QOS_SCHED_SMT_EXPELLER

		root_task_group.smt_expell = TG_SMT_EXPELL;

#endif

#ifdef CONFIG_SCHED_STEAL

		root_task_group.steal_task = TG_STEAL_NO;

#endif

#ifdef CONFIG_RT_GROUP_SCHED

		root_task_group.rt_se = (struct sched_rt_entity **)ptr;

		ptr += nr_cpu_ids * sizeof(void **);
@@ -8712,6 +8715,20 @@ static void sched_free_group(struct task_group *tg) 
	kmem_cache_free(task_group_cache, tg);

}



#ifdef CONFIG_SCHED_STEAL

static void sched_change_steal_group(struct task_struct *tsk, struct task_group *tg)

{

	struct sched_entity *se = &tsk->se;



	se->steal_task = tg->steal_task;

}



static inline void tg_init_steal(struct task_group *tg, struct task_group *ptg)

{

	tg->steal_task = ptg->steal_task;

}

#endif



#ifdef CONFIG_BPF_SCHED

static inline void tg_init_tag(struct task_group *tg, struct task_group *ptg)

{
@@ -8739,6 +8756,10 @@ struct task_group *sched_create_group(struct task_group *parent) 
	if (!alloc_rt_sched_group(tg, parent))

		goto err;



#ifdef CONFIG_SCHED_STEAL

	tg_init_steal(tg, parent);

#endif



#ifdef CONFIG_BPF_SCHED

	tg_init_tag(tg, parent);

#endif
@@ -8814,6 +8835,10 @@ static void sched_change_group(struct task_struct *tsk, int type) 
	sched_change_qos_group(tsk, tg);

#endif



#ifdef CONFIG_SCHED_STEAL

	sched_change_steal_group(tsk, tg);

#endif



#ifdef CONFIG_BPF_SCHED

	/*

	 * This function has cleared and restored the task status,
@@ -9787,6 +9812,81 @@ static inline s64 cpu_qos_read(struct cgroup_subsys_state *css, 
}

#endif



#ifdef CONFIG_SCHED_STEAL

static inline s64 cpu_steal_task_read(struct cgroup_subsys_state *css,

				      struct cftype *cft)

{

	return css_tg(css)->steal_task;

}



void sched_setsteal(struct task_struct *tsk, s64 steal_task)

{

	struct sched_entity *se = &tsk->se;

	int queued, running, queue_flags =

			DEQUEUE_SAVE | DEQUEUE_MOVE | DEQUEUE_NOCLOCK;

	struct rq_flags rf;

	struct rq *rq;



	if (se->steal_task == steal_task)

		return;



	rq = task_rq_lock(tsk, &rf);



	running = task_current(rq, tsk);

	queued = task_on_rq_queued(tsk);



	update_rq_clock(rq);

	if (queued)

		dequeue_task(rq, tsk, queue_flags);

	if (running)

		put_prev_task(rq, tsk);



	se->steal_task = steal_task;



	if (queued)

		enqueue_task(rq, tsk, queue_flags);

	if (running)

		set_next_task(rq, tsk);



	task_rq_unlock(rq, tsk, &rf);

}



int tg_change_steal(struct task_group *tg, void *data)

{

	struct css_task_iter it;

	struct task_struct *tsk;

	s64 steal_task = *(s64 *)data;

	struct cgroup_subsys_state *css = &tg->css;



	tg->steal_task = steal_task;



	css_task_iter_start(css, 0, &it);

	while ((tsk = css_task_iter_next(&it)))

		sched_setsteal(tsk, steal_task);

	css_task_iter_end(&it);



	return 0;

}



static int cpu_steal_task_write(struct cgroup_subsys_state *css,

				struct cftype *cftype, s64 steal_task)

{

	struct task_group *tg = css_tg(css);



	if (!group_steal_used())

		return -EPERM;



	if (steal_task < TG_STEAL_NO || steal_task > TG_STEAL)

		return -EINVAL;



	rcu_read_lock();

	walk_tg_tree_from(tg, tg_change_steal, tg_nop, (void *)(&steal_task));

	rcu_read_unlock();



	return 0;

}

#endif



#ifdef CONFIG_BPF_SCHED

void sched_settag(struct task_struct *tsk, s64 tag)

{
@@ -9957,6 +10057,14 @@ static struct cftype cpu_legacy_files[] = { 
		.write_s64 = cpu_smt_expell_write,

	},

#endif

#ifdef CONFIG_SCHED_STEAL

	{

		.name = "steal_task",

		.flags = CFTYPE_NOT_ON_ROOT,

		.read_s64 = cpu_steal_task_read,

		.write_s64 = cpu_steal_task_write,

	},

#endif

#ifdef CONFIG_BPF_SCHED

	{

		.name = "tag",

kernel/sched/sched.h

+18 −1
Original line number Diff line number Diff line
@@ -402,7 +402,6 @@ struct cfs_bandwidth { 
#endif

};





#ifdef CONFIG_QOS_SCHED_SMART_GRID

#define AD_LEVEL_MAX		8
@@ -497,7 +496,13 @@ struct task_group { 
#else

	KABI_RESERVE(2)

#endif



#ifdef CONFIG_SCHED_STEAL

	KABI_USE(3, int steal_task)

#else

	KABI_RESERVE(3)

#endif



#if defined(CONFIG_QOS_SCHED_SMART_GRID) && !defined(__GENKSYMS__)

	KABI_USE(4, struct auto_affinity *auto_affinity)

#else
@@ -505,6 +510,18 @@ struct task_group { 
#endif

};



#ifdef CONFIG_SCHED_STEAL

enum tg_steal_task {

	TG_STEAL_NO = 0,

	TG_STEAL = 1,

};



static inline bool is_tg_steal(int steal_task)

{

	return steal_task == TG_STEAL;

}

#endif



#ifdef CONFIG_FAIR_GROUP_SCHED

#define ROOT_TASK_GROUP_LOAD	NICE_0_LOAD