Commit 8803e6a7 authored by Tejun Heo's avatar Tejun Heo
Browse files

sched_ext: Factor out reenq_local() from scx_bpf_reenqueue_local() 



Factor out the core re-enqueue logic from scx_bpf_reenqueue_local() into a
new reenq_local() helper function. scx_bpf_reenqueue_local() now handles the
BPF kfunc checks and calls reenq_local() to perform the actual work.

This is a prep patch to allow reenq_local() to be called from other contexts.

Reviewed-by: default avatarEmil Tsalapatis <emil@etsalapatis.com>
Signed-off-by: default avatarTejun Heo <tj@kernel.org>
parent 180b4ac3

kernel/sched/ext.c

+29 −21
Original line number Diff line number Diff line
@@ -5879,32 +5879,12 @@ static const struct btf_kfunc_id_set scx_kfunc_set_dispatch = { 
	.set			= &scx_kfunc_ids_dispatch,

};



__bpf_kfunc_start_defs();



/**

 * scx_bpf_reenqueue_local - Re-enqueue tasks on a local DSQ

 *

 * Iterate over all of the tasks currently enqueued on the local DSQ of the

 * caller's CPU, and re-enqueue them in the BPF scheduler. Returns the number of

 * processed tasks. Can only be called from ops.cpu_release().

 */

__bpf_kfunc u32 scx_bpf_reenqueue_local(void)

static u32 reenq_local(struct rq *rq)

{

	struct scx_sched *sch;

	LIST_HEAD(tasks);

	u32 nr_enqueued = 0;

	struct rq *rq;

	struct task_struct *p, *n;



	guard(rcu)();

	sch = rcu_dereference(scx_root);

	if (unlikely(!sch))

		return 0;



	if (!scx_kf_allowed(sch, SCX_KF_CPU_RELEASE))

		return 0;



	rq = cpu_rq(smp_processor_id());

	lockdep_assert_rq_held(rq);



	/*
@@ -5941,6 +5921,34 @@ __bpf_kfunc u32 scx_bpf_reenqueue_local(void) 
	return nr_enqueued;

}



__bpf_kfunc_start_defs();



/**

 * scx_bpf_reenqueue_local - Re-enqueue tasks on a local DSQ

 *

 * Iterate over all of the tasks currently enqueued on the local DSQ of the

 * caller's CPU, and re-enqueue them in the BPF scheduler. Returns the number of

 * processed tasks. Can only be called from ops.cpu_release().

 */

__bpf_kfunc u32 scx_bpf_reenqueue_local(void)

{

	struct scx_sched *sch;

	struct rq *rq;



	guard(rcu)();

	sch = rcu_dereference(scx_root);

	if (unlikely(!sch))

		return 0;



	if (!scx_kf_allowed(sch, SCX_KF_CPU_RELEASE))

		return 0;



	rq = cpu_rq(smp_processor_id());

	lockdep_assert_rq_held(rq);



	return reenq_local(rq);

}



__bpf_kfunc_end_defs();



BTF_KFUNCS_START(scx_kfunc_ids_cpu_release)