Commit e776b26e authored by Tejun Heo's avatar Tejun Heo
Browse files

sched_ext: Remove cpu.weight / cpu.idle unimplemented warnings 



sched_ext generates warnings when cpu.weight / cpu.idle are set to
non-default values if the BPF scheduler doesn't implement weight support.
These warnings don't provide much value while adding constant annoyance. A
BPF scheduler may not implement any particular behavior and there's nothing
particularly special about missing cgroup weight support. Drop the warnings.

Signed-off-by: default avatarTejun Heo <tj@kernel.org>
parent 47068309

kernel/sched/ext.c

+1 −40
Original line number Diff line number Diff line
@@ -3899,35 +3899,6 @@ bool scx_can_stop_tick(struct rq *rq) 


DEFINE_STATIC_PERCPU_RWSEM(scx_cgroup_rwsem);

static bool scx_cgroup_enabled;

static bool cgroup_warned_missing_weight;

static bool cgroup_warned_missing_idle;



static void scx_cgroup_warn_missing_weight(struct task_group *tg)

{

	if (scx_ops_enable_state() == SCX_OPS_DISABLED ||

	    cgroup_warned_missing_weight)

		return;



	if ((scx_ops.flags & SCX_OPS_HAS_CGROUP_WEIGHT) || !tg->css.parent)

		return;



	pr_warn("sched_ext: \"%s\" does not implement cgroup cpu.weight\n",

		scx_ops.name);

	cgroup_warned_missing_weight = true;

}



static void scx_cgroup_warn_missing_idle(struct task_group *tg)

{

	if (!scx_cgroup_enabled || cgroup_warned_missing_idle)

		return;



	if (!tg->idle)

		return;



	pr_warn("sched_ext: \"%s\" does not implement cgroup cpu.idle\n",

		scx_ops.name);

	cgroup_warned_missing_idle = true;

}



int scx_tg_online(struct task_group *tg)

{
@@ -3937,8 +3908,6 @@ int scx_tg_online(struct task_group *tg) 


	percpu_down_read(&scx_cgroup_rwsem);



	scx_cgroup_warn_missing_weight(tg);



	if (scx_cgroup_enabled) {

		if (SCX_HAS_OP(cgroup_init)) {

			struct scx_cgroup_init_args args =
@@ -4076,9 +4045,7 @@ void scx_group_set_weight(struct task_group *tg, unsigned long weight) 


void scx_group_set_idle(struct task_group *tg, bool idle)

{

	percpu_down_read(&scx_cgroup_rwsem);

	scx_cgroup_warn_missing_idle(tg);

	percpu_up_read(&scx_cgroup_rwsem);

	/* TODO: Implement ops->cgroup_set_idle() */

}



static void scx_cgroup_lock(void)
@@ -4272,9 +4239,6 @@ static int scx_cgroup_init(void) 


	percpu_rwsem_assert_held(&scx_cgroup_rwsem);



	cgroup_warned_missing_weight = false;

	cgroup_warned_missing_idle = false;



	/*

	 * scx_tg_on/offline() are excluded through scx_cgroup_rwsem. If we walk

	 * cgroups and init, all online cgroups are initialized.
@@ -4284,9 +4248,6 @@ static int scx_cgroup_init(void) 
		struct task_group *tg = css_tg(css);

		struct scx_cgroup_init_args args = { .weight = tg->scx_weight };



		scx_cgroup_warn_missing_weight(tg);

		scx_cgroup_warn_missing_idle(tg);



		if ((tg->scx_flags &

		     (SCX_TG_ONLINE | SCX_TG_INITED)) != SCX_TG_ONLINE)

			continue;