Commit 347ed2d5 authored by zhidao su's avatar zhidao su Committed by Tejun Heo
Browse files

sched/ext: Implement cgroup_set_idle() callback 



Implement the missing cgroup_set_idle() callback that was marked as a
TODO. This allows BPF schedulers to be notified when a cgroup's idle
state changes, enabling them to adjust their scheduling behavior
accordingly.

The implementation follows the same pattern as other cgroup callbacks
like cgroup_set_weight() and cgroup_set_bandwidth(). It checks if the
BPF scheduler has implemented the callback and invokes it with the
appropriate parameters.

Fixes a spelling error in the cgroup_set_bandwidth() documentation.

tj: s/scx_cgroup_rwsem/scx_cgroup_ops_rwsem/ to fix build breakage.

Signed-off-by: default avatarzhidao su <soolaugust@gmail.com>
Signed-off-by: default avatarTejun Heo <tj@kernel.org>
parent bd7143e7

include/linux/sched/ext.h

+1 −0
Original line number Diff line number Diff line
@@ -228,6 +228,7 @@ struct scx_task_group { 
	u64			bw_period_us;

	u64			bw_quota_us;

	u64			bw_burst_us;

	bool			idle;

#endif

};

kernel/sched/ext.c

+15 −1
Original line number Diff line number Diff line
@@ -3066,6 +3066,7 @@ void scx_tg_init(struct task_group *tg) 
	tg->scx.weight = CGROUP_WEIGHT_DFL;

	tg->scx.bw_period_us = default_bw_period_us();

	tg->scx.bw_quota_us = RUNTIME_INF;

	tg->scx.idle = false;

}



int scx_tg_online(struct task_group *tg)
@@ -3214,7 +3215,18 @@ void scx_group_set_weight(struct task_group *tg, unsigned long weight) 


void scx_group_set_idle(struct task_group *tg, bool idle)

{

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

	struct scx_sched *sch = scx_root;



	percpu_down_read(&scx_cgroup_ops_rwsem);



	if (scx_cgroup_enabled && SCX_HAS_OP(sch, cgroup_set_idle))

		SCX_CALL_OP(sch, SCX_KF_UNLOCKED, cgroup_set_idle, NULL,

			    tg_cgrp(tg), idle);



	/* Update the task group's idle state */

	tg->scx.idle = idle;



	percpu_up_read(&scx_cgroup_ops_rwsem);

}



void scx_group_set_bandwidth(struct task_group *tg,
@@ -5017,6 +5029,7 @@ static void sched_ext_ops__cgroup_move(struct task_struct *p, struct cgroup *fro 
static void sched_ext_ops__cgroup_cancel_move(struct task_struct *p, struct cgroup *from, struct cgroup *to) {}

static void sched_ext_ops__cgroup_set_weight(struct cgroup *cgrp, u32 weight) {}

static void sched_ext_ops__cgroup_set_bandwidth(struct cgroup *cgrp, u64 period_us, u64 quota_us, u64 burst_us) {}

static void sched_ext_ops__cgroup_set_idle(struct cgroup *cgrp, bool idle) {}

#endif

static void sched_ext_ops__cpu_online(s32 cpu) {}

static void sched_ext_ops__cpu_offline(s32 cpu) {}
@@ -5055,6 +5068,7 @@ static struct sched_ext_ops __bpf_ops_sched_ext_ops = { 
	.cgroup_cancel_move	= sched_ext_ops__cgroup_cancel_move,

	.cgroup_set_weight	= sched_ext_ops__cgroup_set_weight,

	.cgroup_set_bandwidth	= sched_ext_ops__cgroup_set_bandwidth,

	.cgroup_set_idle	= sched_ext_ops__cgroup_set_idle,

#endif

	.cpu_online		= sched_ext_ops__cpu_online,

	.cpu_offline		= sched_ext_ops__cpu_offline,

kernel/sched/ext_internal.h

+12 −1
Original line number Diff line number Diff line
@@ -697,12 +697,23 @@ struct sched_ext_ops { 
	 * 2_500_000. @cgrp is entitled to 2.5 CPUs. @burst_us can be

	 * interpreted in the same fashion and specifies how much @cgrp can

	 * burst temporarily. The specific control mechanism and thus the

	 * interpretation of @period_us and burstiness is upto to the BPF

	 * interpretation of @period_us and burstiness is up to the BPF

	 * scheduler.

	 */

	void (*cgroup_set_bandwidth)(struct cgroup *cgrp,

				     u64 period_us, u64 quota_us, u64 burst_us);



	/**

	 * @cgroup_set_idle: A cgroup's idle state is being changed

	 * @cgrp: cgroup whose idle state is being updated

	 * @idle: whether the cgroup is entering or exiting idle state

	 *

	 * Update @cgrp's idle state to @idle. This callback is invoked when

	 * a cgroup transitions between idle and non-idle states, allowing the

	 * BPF scheduler to adjust its behavior accordingly.

	 */

	void (*cgroup_set_idle)(struct cgroup *cgrp, bool idle);



#endif	/* CONFIG_EXT_GROUP_SCHED */



	/*