tools/sched_ext/include/scx/compat.bpf.h - linux - Git at Google

 /* SPDX-License-Identifier: GPL-2.0 */
 /*
  * Copyright (c) 2024 Meta Platforms, Inc. and affiliates.
  * Copyright (c) 2024 Tejun Heo <tj@kernel.org>
  * Copyright (c) 2024 David Vernet <dvernet@meta.com>
  */
 #ifndef __SCX_COMPAT_BPF_H
 #define __SCX_COMPAT_BPF_H

 #define __COMPAT_ENUM_OR_ZERO(__type, __ent)					\
 ({										\
 	__type __ret = 0;							\
 	if (bpf_core_enum_value_exists(__type, __ent))				\
 		__ret = __ent;							\
 	__ret;									\
 })

 /* v6.12: 819513666966 ("sched_ext: Add cgroup support") */
 #define __COMPAT_scx_bpf_task_cgroup(p)						\
 	(bpf_ksym_exists(scx_bpf_task_cgroup) ?					\
 	 scx_bpf_task_cgroup((p)) : NULL)

 /*
  * v6.13: The verb `dispatch` was too overloaded and confusing. kfuncs are
  * renamed to unload the verb.
  *
  * Build error is triggered if old names are used. New binaries work with both
  * new and old names. The compat macros will be removed on v6.15 release.
  *
  * scx_bpf_dispatch_from_dsq() and friends were added during v6.12 by
  * 4c30f5ce4f7a ("sched_ext: Implement scx_bpf_dispatch[_vtime]_from_dsq()").
  * Preserve __COMPAT macros until v6.15.
  */
 void scx_bpf_dispatch___compat(struct task_struct *p, u64 dsq_id, u64 slice, u64 enq_flags) __ksym __weak;
 void scx_bpf_dispatch_vtime___compat(struct task_struct *p, u64 dsq_id, u64 slice, u64 vtime, u64 enq_flags) __ksym __weak;
 bool scx_bpf_consume___compat(u64 dsq_id) __ksym __weak;
 void scx_bpf_dispatch_from_dsq_set_slice___compat(struct bpf_iter_scx_dsq *it__iter, u64 slice) __ksym __weak;
 void scx_bpf_dispatch_from_dsq_set_vtime___compat(struct bpf_iter_scx_dsq *it__iter, u64 vtime) __ksym __weak;
 bool scx_bpf_dispatch_from_dsq___compat(struct bpf_iter_scx_dsq *it__iter, struct task_struct *p, u64 dsq_id, u64 enq_flags) __ksym __weak;
 bool scx_bpf_dispatch_vtime_from_dsq___compat(struct bpf_iter_scx_dsq *it__iter, struct task_struct *p, u64 dsq_id, u64 enq_flags) __ksym __weak;
 int bpf_cpumask_populate(struct cpumask *dst, void *src, size_t src__sz) __ksym __weak;

 #define scx_bpf_dsq_insert(p, dsq_id, slice, enq_flags)				\
 	(bpf_ksym_exists(scx_bpf_dsq_insert) ?					\
 	 scx_bpf_dsq_insert((p), (dsq_id), (slice), (enq_flags)) :		\
 	 scx_bpf_dispatch___compat((p), (dsq_id), (slice), (enq_flags)))

 #define scx_bpf_dsq_insert_vtime(p, dsq_id, slice, vtime, enq_flags)		\
 	(bpf_ksym_exists(scx_bpf_dsq_insert_vtime) ?				\
 	 scx_bpf_dsq_insert_vtime((p), (dsq_id), (slice), (vtime), (enq_flags)) : \
 	 scx_bpf_dispatch_vtime___compat((p), (dsq_id), (slice), (vtime), (enq_flags)))

 #define scx_bpf_dsq_move_to_local(dsq_id)					\
 	(bpf_ksym_exists(scx_bpf_dsq_move_to_local) ?				\
 	 scx_bpf_dsq_move_to_local((dsq_id)) :					\
 	 scx_bpf_consume___compat((dsq_id)))

 #define __COMPAT_scx_bpf_dsq_move_set_slice(it__iter, slice)			\
 	(bpf_ksym_exists(scx_bpf_dsq_move_set_slice) ?				\
 	 scx_bpf_dsq_move_set_slice((it__iter), (slice)) :			\
 	 (bpf_ksym_exists(scx_bpf_dispatch_from_dsq_set_slice___compat) ?	\
 	  scx_bpf_dispatch_from_dsq_set_slice___compat((it__iter), (slice)) :	\
 	  (void)0))

 #define __COMPAT_scx_bpf_dsq_move_set_vtime(it__iter, vtime)			\
 	(bpf_ksym_exists(scx_bpf_dsq_move_set_vtime) ?				\
 	 scx_bpf_dsq_move_set_vtime((it__iter), (vtime)) :			\
 	 (bpf_ksym_exists(scx_bpf_dispatch_from_dsq_set_vtime___compat) ?	\
 	  scx_bpf_dispatch_from_dsq_set_vtime___compat((it__iter), (vtime)) :	\
 	  (void) 0))

 #define __COMPAT_scx_bpf_dsq_move(it__iter, p, dsq_id, enq_flags)		\
 	(bpf_ksym_exists(scx_bpf_dsq_move) ?					\
 	 scx_bpf_dsq_move((it__iter), (p), (dsq_id), (enq_flags)) :		\
 	 (bpf_ksym_exists(scx_bpf_dispatch_from_dsq___compat) ?			\
 	  scx_bpf_dispatch_from_dsq___compat((it__iter), (p), (dsq_id), (enq_flags)) : \
 	  false))

 #define __COMPAT_scx_bpf_dsq_move_vtime(it__iter, p, dsq_id, enq_flags)		\
 	(bpf_ksym_exists(scx_bpf_dsq_move_vtime) ?				\
 	 scx_bpf_dsq_move_vtime((it__iter), (p), (dsq_id), (enq_flags)) :	\
 	 (bpf_ksym_exists(scx_bpf_dispatch_vtime_from_dsq___compat) ?		\
 	  scx_bpf_dispatch_vtime_from_dsq___compat((it__iter), (p), (dsq_id), (enq_flags)) : \
 	  false))

 #define __COMPAT_bpf_cpumask_populate(cpumask, src, size__sz)		\
 	(bpf_ksym_exists(bpf_cpumask_populate) ?			\
 	 (bpf_cpumask_populate(cpumask, src, size__sz)) : -EOPNOTSUPP)

 #define scx_bpf_dispatch(p, dsq_id, slice, enq_flags)				\
 	_Static_assert(false, "scx_bpf_dispatch() renamed to scx_bpf_dsq_insert()")

 #define scx_bpf_dispatch_vtime(p, dsq_id, slice, vtime, enq_flags)		\
 	_Static_assert(false, "scx_bpf_dispatch_vtime() renamed to scx_bpf_dsq_insert_vtime()")

 #define scx_bpf_consume(dsq_id) ({						\
 	_Static_assert(false, "scx_bpf_consume() renamed to scx_bpf_dsq_move_to_local()"); \
 	false;									\
 })

 #define scx_bpf_dispatch_from_dsq_set_slice(it__iter, slice)		\
 	_Static_assert(false, "scx_bpf_dispatch_from_dsq_set_slice() renamed to scx_bpf_dsq_move_set_slice()")

 #define scx_bpf_dispatch_from_dsq_set_vtime(it__iter, vtime)		\
 	_Static_assert(false, "scx_bpf_dispatch_from_dsq_set_vtime() renamed to scx_bpf_dsq_move_set_vtime()")

 #define scx_bpf_dispatch_from_dsq(it__iter, p, dsq_id, enq_flags) ({	\
 	_Static_assert(false, "scx_bpf_dispatch_from_dsq() renamed to scx_bpf_dsq_move()"); \
 	false;									\
 })

 #define scx_bpf_dispatch_vtime_from_dsq(it__iter, p, dsq_id, enq_flags) ({  \
 	_Static_assert(false, "scx_bpf_dispatch_vtime_from_dsq() renamed to scx_bpf_dsq_move_vtime()"); \
 	false;									\
 })

 #define __COMPAT_scx_bpf_dispatch_from_dsq_set_slice(it__iter, slice)		\
 	_Static_assert(false, "__COMPAT_scx_bpf_dispatch_from_dsq_set_slice() renamed to __COMPAT_scx_bpf_dsq_move_set_slice()")

 #define __COMPAT_scx_bpf_dispatch_from_dsq_set_vtime(it__iter, vtime)		\
 	_Static_assert(false, "__COMPAT_scx_bpf_dispatch_from_dsq_set_vtime() renamed to __COMPAT_scx_bpf_dsq_move_set_vtime()")

 #define __COMPAT_scx_bpf_dispatch_from_dsq(it__iter, p, dsq_id, enq_flags) ({	\
 	_Static_assert(false, "__COMPAT_scx_bpf_dispatch_from_dsq() renamed to __COMPAT_scx_bpf_dsq_move()"); \
 	false;									\
 })

 #define __COMPAT_scx_bpf_dispatch_vtime_from_dsq(it__iter, p, dsq_id, enq_flags) ({  \
 	_Static_assert(false, "__COMPAT_scx_bpf_dispatch_vtime_from_dsq() renamed to __COMPAT_scx_bpf_dsq_move_vtime()"); \
 	false;									\
 })

 /**
  * __COMPAT_is_enq_cpu_selected - Test if SCX_ENQ_CPU_SELECTED is on
  * in a compatible way. We will preserve this __COMPAT helper until v6.16.
  *
  * @enq_flags: enqueue flags from ops.enqueue()
  *
  * Return: True if SCX_ENQ_CPU_SELECTED is turned on in @enq_flags
  */
 static inline bool __COMPAT_is_enq_cpu_selected(u64 enq_flags)
 {
 #ifdef HAVE_SCX_ENQ_CPU_SELECTED
 	/*
 	 * This is the case that a BPF code compiled against vmlinux.h
 	 * where the enum SCX_ENQ_CPU_SELECTED exists.
 	 */

 	/*
 	 * We should temporarily suspend the macro expansion of
 	 * 'SCX_ENQ_CPU_SELECTED'. This avoids 'SCX_ENQ_CPU_SELECTED' being
 	 * rewritten to '__SCX_ENQ_CPU_SELECTED' when 'SCX_ENQ_CPU_SELECTED'
 	 * is defined in 'scripts/gen_enums.py'.
 	 */
 #pragma push_macro("SCX_ENQ_CPU_SELECTED")
 #undef SCX_ENQ_CPU_SELECTED
 	u64 flag;

 	/*
 	 * When the kernel did not have SCX_ENQ_CPU_SELECTED,
 	 * select_task_rq_scx() has never been skipped. Thus, this case
 	 * should be considered that the CPU has already been selected.
 	 */
 	if (!bpf_core_enum_value_exists(enum scx_enq_flags,
 					SCX_ENQ_CPU_SELECTED))
 		return true;

 	flag = bpf_core_enum_value(enum scx_enq_flags, SCX_ENQ_CPU_SELECTED);
 	return enq_flags & flag;

 	/*
 	 * Once done, resume the macro expansion of 'SCX_ENQ_CPU_SELECTED'.
 	 */
 #pragma pop_macro("SCX_ENQ_CPU_SELECTED")
 #else
 	/*
 	 * This is the case that a BPF code compiled against vmlinux.h
 	 * where the enum SCX_ENQ_CPU_SELECTED does NOT exist.
 	 */
 	return true;
 #endif /* HAVE_SCX_ENQ_CPU_SELECTED */
 }


 #define scx_bpf_now()								\
 	(bpf_ksym_exists(scx_bpf_now) ?						\
 	 scx_bpf_now() :							\
 	 bpf_ktime_get_ns())

 /*
  * v6.15: Introduce event counters.
  *
  * Preserve the following macro until v6.17.
  */
 #define __COMPAT_scx_bpf_events(events, size)					\
 	(bpf_ksym_exists(scx_bpf_events) ?					\
 	 scx_bpf_events(events, size) : ({}))

 /*
  * v6.15: Introduce NUMA-aware kfuncs to operate with per-node idle
  * cpumasks.
  *
  * Preserve the following __COMPAT_scx_*_node macros until v6.17.
  */
 #define __COMPAT_scx_bpf_nr_node_ids()						\
 	(bpf_ksym_exists(scx_bpf_nr_node_ids) ?					\
 	 scx_bpf_nr_node_ids() : 1U)

 #define __COMPAT_scx_bpf_cpu_node(cpu)						\
 	(bpf_ksym_exists(scx_bpf_cpu_node) ?					\
 	 scx_bpf_cpu_node(cpu) : 0)

 #define __COMPAT_scx_bpf_get_idle_cpumask_node(node)				\
 	(bpf_ksym_exists(scx_bpf_get_idle_cpumask_node) ?			\
 	 scx_bpf_get_idle_cpumask_node(node) :					\
 	 scx_bpf_get_idle_cpumask())						\

 #define __COMPAT_scx_bpf_get_idle_smtmask_node(node)				\
 	(bpf_ksym_exists(scx_bpf_get_idle_smtmask_node) ?			\
 	 scx_bpf_get_idle_smtmask_node(node) :					\
 	 scx_bpf_get_idle_smtmask())

 #define __COMPAT_scx_bpf_pick_idle_cpu_node(cpus_allowed, node, flags)		\
 	(bpf_ksym_exists(scx_bpf_pick_idle_cpu_node) ?				\
 	 scx_bpf_pick_idle_cpu_node(cpus_allowed, node, flags) :		\
 	 scx_bpf_pick_idle_cpu(cpus_allowed, flags))

 #define __COMPAT_scx_bpf_pick_any_cpu_node(cpus_allowed, node, flags)		\
 	(bpf_ksym_exists(scx_bpf_pick_any_cpu_node) ?				\
 	 scx_bpf_pick_any_cpu_node(cpus_allowed, node, flags) :			\
 	 scx_bpf_pick_any_cpu(cpus_allowed, flags))

 /*
  * v6.18: Add a helper to retrieve the current task running on a CPU.
  *
  * Keep this helper available until v6.20 for compatibility.
  */
 static inline struct task_struct *__COMPAT_scx_bpf_cpu_curr(int cpu)
 {
 	struct rq *rq;

 	if (bpf_ksym_exists(scx_bpf_cpu_curr))
 		return scx_bpf_cpu_curr(cpu);

 	rq = scx_bpf_cpu_rq(cpu);

 	return rq ? rq->curr : NULL;
 }

 /*
  * Define sched_ext_ops. This may be expanded to define multiple variants for
  * backward compatibility. See compat.h::SCX_OPS_LOAD/ATTACH().
  */
 #define SCX_OPS_DEFINE(__name, ...)						\
 	SEC(".struct_ops.link")							\
 	struct sched_ext_ops __name = {						\
 		__VA_ARGS__,							\
 	};

 #endif	/* __SCX_COMPAT_BPF_H */
	/* SPDX-License-Identifier: GPL-2.0 */
	/*
	* Copyright (c) 2024 Meta Platforms, Inc. and affiliates.
	* Copyright (c) 2024 Tejun Heo <tj@kernel.org>
	* Copyright (c) 2024 David Vernet <dvernet@meta.com>
	*/
	#ifndef __SCX_COMPAT_BPF_H
	#define __SCX_COMPAT_BPF_H

	#define __COMPAT_ENUM_OR_ZERO(__type, __ent) \
	({ \
	__type __ret = 0; \
	if (bpf_core_enum_value_exists(__type, __ent)) \
	__ret = __ent; \
	__ret; \
	})

	/* v6.12: 819513666966 ("sched_ext: Add cgroup support") */
	#define __COMPAT_scx_bpf_task_cgroup(p) \
	(bpf_ksym_exists(scx_bpf_task_cgroup) ? \
	scx_bpf_task_cgroup((p)) : NULL)

	/*
	* v6.13: The verb `dispatch` was too overloaded and confusing. kfuncs are
	* renamed to unload the verb.
	*
	* Build error is triggered if old names are used. New binaries work with both
	* new and old names. The compat macros will be removed on v6.15 release.
	*
	* scx_bpf_dispatch_from_dsq() and friends were added during v6.12 by
	* 4c30f5ce4f7a ("sched_ext: Implement scx_bpf_dispatch[_vtime]_from_dsq()").
	* Preserve __COMPAT macros until v6.15.
	*/
	void scx_bpf_dispatch___compat(struct task_struct *p, u64 dsq_id, u64 slice, u64 enq_flags) __ksym __weak;
	void scx_bpf_dispatch_vtime___compat(struct task_struct *p, u64 dsq_id, u64 slice, u64 vtime, u64 enq_flags) __ksym __weak;
	bool scx_bpf_consume___compat(u64 dsq_id) __ksym __weak;
	void scx_bpf_dispatch_from_dsq_set_slice___compat(struct bpf_iter_scx_dsq *it__iter, u64 slice) __ksym __weak;
	void scx_bpf_dispatch_from_dsq_set_vtime___compat(struct bpf_iter_scx_dsq *it__iter, u64 vtime) __ksym __weak;
	bool scx_bpf_dispatch_from_dsq___compat(struct bpf_iter_scx_dsq it__iter, struct task_struct p, u64 dsq_id, u64 enq_flags) __ksym __weak;
	bool scx_bpf_dispatch_vtime_from_dsq___compat(struct bpf_iter_scx_dsq it__iter, struct task_struct p, u64 dsq_id, u64 enq_flags) __ksym __weak;
	int bpf_cpumask_populate(struct cpumask dst, void src, size_t src__sz) __ksym __weak;

	#define scx_bpf_dsq_insert(p, dsq_id, slice, enq_flags) \
	(bpf_ksym_exists(scx_bpf_dsq_insert) ? \
	scx_bpf_dsq_insert((p), (dsq_id), (slice), (enq_flags)) : \
	scx_bpf_dispatch___compat((p), (dsq_id), (slice), (enq_flags)))

	#define scx_bpf_dsq_insert_vtime(p, dsq_id, slice, vtime, enq_flags) \
	(bpf_ksym_exists(scx_bpf_dsq_insert_vtime) ? \
	scx_bpf_dsq_insert_vtime((p), (dsq_id), (slice), (vtime), (enq_flags)) : \
	scx_bpf_dispatch_vtime___compat((p), (dsq_id), (slice), (vtime), (enq_flags)))

	#define scx_bpf_dsq_move_to_local(dsq_id) \
	(bpf_ksym_exists(scx_bpf_dsq_move_to_local) ? \
	scx_bpf_dsq_move_to_local((dsq_id)) : \
	scx_bpf_consume___compat((dsq_id)))

	#define __COMPAT_scx_bpf_dsq_move_set_slice(it__iter, slice) \
	(bpf_ksym_exists(scx_bpf_dsq_move_set_slice) ? \
	scx_bpf_dsq_move_set_slice((it__iter), (slice)) : \
	(bpf_ksym_exists(scx_bpf_dispatch_from_dsq_set_slice___compat) ? \
	scx_bpf_dispatch_from_dsq_set_slice___compat((it__iter), (slice)) : \
	(void)0))

	#define __COMPAT_scx_bpf_dsq_move_set_vtime(it__iter, vtime) \
	(bpf_ksym_exists(scx_bpf_dsq_move_set_vtime) ? \
	scx_bpf_dsq_move_set_vtime((it__iter), (vtime)) : \
	(bpf_ksym_exists(scx_bpf_dispatch_from_dsq_set_vtime___compat) ? \
	scx_bpf_dispatch_from_dsq_set_vtime___compat((it__iter), (vtime)) : \
	(void) 0))

	#define __COMPAT_scx_bpf_dsq_move(it__iter, p, dsq_id, enq_flags) \
	(bpf_ksym_exists(scx_bpf_dsq_move) ? \
	scx_bpf_dsq_move((it__iter), (p), (dsq_id), (enq_flags)) : \
	(bpf_ksym_exists(scx_bpf_dispatch_from_dsq___compat) ? \
	scx_bpf_dispatch_from_dsq___compat((it__iter), (p), (dsq_id), (enq_flags)) : \
	false))

	#define __COMPAT_scx_bpf_dsq_move_vtime(it__iter, p, dsq_id, enq_flags) \
	(bpf_ksym_exists(scx_bpf_dsq_move_vtime) ? \
	scx_bpf_dsq_move_vtime((it__iter), (p), (dsq_id), (enq_flags)) : \
	(bpf_ksym_exists(scx_bpf_dispatch_vtime_from_dsq___compat) ? \
	scx_bpf_dispatch_vtime_from_dsq___compat((it__iter), (p), (dsq_id), (enq_flags)) : \
	false))

	#define __COMPAT_bpf_cpumask_populate(cpumask, src, size__sz) \
	(bpf_ksym_exists(bpf_cpumask_populate) ? \
	(bpf_cpumask_populate(cpumask, src, size__sz)) : -EOPNOTSUPP)

	#define scx_bpf_dispatch(p, dsq_id, slice, enq_flags) \
	_Static_assert(false, "scx_bpf_dispatch() renamed to scx_bpf_dsq_insert()")

	#define scx_bpf_dispatch_vtime(p, dsq_id, slice, vtime, enq_flags) \
	_Static_assert(false, "scx_bpf_dispatch_vtime() renamed to scx_bpf_dsq_insert_vtime()")

	#define scx_bpf_consume(dsq_id) ({ \
	_Static_assert(false, "scx_bpf_consume() renamed to scx_bpf_dsq_move_to_local()"); \
	false; \
	})

	#define scx_bpf_dispatch_from_dsq_set_slice(it__iter, slice) \
	_Static_assert(false, "scx_bpf_dispatch_from_dsq_set_slice() renamed to scx_bpf_dsq_move_set_slice()")

	#define scx_bpf_dispatch_from_dsq_set_vtime(it__iter, vtime) \
	_Static_assert(false, "scx_bpf_dispatch_from_dsq_set_vtime() renamed to scx_bpf_dsq_move_set_vtime()")

	#define scx_bpf_dispatch_from_dsq(it__iter, p, dsq_id, enq_flags) ({ \
	_Static_assert(false, "scx_bpf_dispatch_from_dsq() renamed to scx_bpf_dsq_move()"); \
	false; \
	})

	#define scx_bpf_dispatch_vtime_from_dsq(it__iter, p, dsq_id, enq_flags) ({ \
	_Static_assert(false, "scx_bpf_dispatch_vtime_from_dsq() renamed to scx_bpf_dsq_move_vtime()"); \
	false; \
	})

	#define __COMPAT_scx_bpf_dispatch_from_dsq_set_slice(it__iter, slice) \
	_Static_assert(false, "__COMPAT_scx_bpf_dispatch_from_dsq_set_slice() renamed to __COMPAT_scx_bpf_dsq_move_set_slice()")

	#define __COMPAT_scx_bpf_dispatch_from_dsq_set_vtime(it__iter, vtime) \
	_Static_assert(false, "__COMPAT_scx_bpf_dispatch_from_dsq_set_vtime() renamed to __COMPAT_scx_bpf_dsq_move_set_vtime()")

	#define __COMPAT_scx_bpf_dispatch_from_dsq(it__iter, p, dsq_id, enq_flags) ({ \
	_Static_assert(false, "__COMPAT_scx_bpf_dispatch_from_dsq() renamed to __COMPAT_scx_bpf_dsq_move()"); \
	false; \
	})

	#define __COMPAT_scx_bpf_dispatch_vtime_from_dsq(it__iter, p, dsq_id, enq_flags) ({ \
	_Static_assert(false, "__COMPAT_scx_bpf_dispatch_vtime_from_dsq() renamed to __COMPAT_scx_bpf_dsq_move_vtime()"); \
	false; \
	})

	/**
	* __COMPAT_is_enq_cpu_selected - Test if SCX_ENQ_CPU_SELECTED is on
	* in a compatible way. We will preserve this __COMPAT helper until v6.16.
	*
	* @enq_flags: enqueue flags from ops.enqueue()
	*
	* Return: True if SCX_ENQ_CPU_SELECTED is turned on in @enq_flags
	*/
	static inline bool __COMPAT_is_enq_cpu_selected(u64 enq_flags)
	{
	#ifdef HAVE_SCX_ENQ_CPU_SELECTED
	/*
	* This is the case that a BPF code compiled against vmlinux.h
	* where the enum SCX_ENQ_CPU_SELECTED exists.
	*/

	/*
	* We should temporarily suspend the macro expansion of
	* 'SCX_ENQ_CPU_SELECTED'. This avoids 'SCX_ENQ_CPU_SELECTED' being
	* rewritten to '__SCX_ENQ_CPU_SELECTED' when 'SCX_ENQ_CPU_SELECTED'
	* is defined in 'scripts/gen_enums.py'.
	*/
	#pragma push_macro("SCX_ENQ_CPU_SELECTED")
	#undef SCX_ENQ_CPU_SELECTED
	u64 flag;

	/*
	* When the kernel did not have SCX_ENQ_CPU_SELECTED,
	* select_task_rq_scx() has never been skipped. Thus, this case
	* should be considered that the CPU has already been selected.
	*/
	if (!bpf_core_enum_value_exists(enum scx_enq_flags,
	SCX_ENQ_CPU_SELECTED))
	return true;

	flag = bpf_core_enum_value(enum scx_enq_flags, SCX_ENQ_CPU_SELECTED);
	return enq_flags & flag;

	/*
	* Once done, resume the macro expansion of 'SCX_ENQ_CPU_SELECTED'.
	*/
	#pragma pop_macro("SCX_ENQ_CPU_SELECTED")
	#else
	/*
	* This is the case that a BPF code compiled against vmlinux.h
	* where the enum SCX_ENQ_CPU_SELECTED does NOT exist.
	*/
	return true;
	#endif /* HAVE_SCX_ENQ_CPU_SELECTED */
	}


	#define scx_bpf_now() \
	(bpf_ksym_exists(scx_bpf_now) ? \
	scx_bpf_now() : \
	bpf_ktime_get_ns())

	/*
	* v6.15: Introduce event counters.
	*
	* Preserve the following macro until v6.17.
	*/
	#define __COMPAT_scx_bpf_events(events, size) \
	(bpf_ksym_exists(scx_bpf_events) ? \
	scx_bpf_events(events, size) : ({}))

	/*
	* v6.15: Introduce NUMA-aware kfuncs to operate with per-node idle
	* cpumasks.
	*
	* Preserve the following __COMPAT_scx_*_node macros until v6.17.
	*/
	#define __COMPAT_scx_bpf_nr_node_ids() \
	(bpf_ksym_exists(scx_bpf_nr_node_ids) ? \
	scx_bpf_nr_node_ids() : 1U)

	#define __COMPAT_scx_bpf_cpu_node(cpu) \
	(bpf_ksym_exists(scx_bpf_cpu_node) ? \
	scx_bpf_cpu_node(cpu) : 0)

	#define __COMPAT_scx_bpf_get_idle_cpumask_node(node) \
	(bpf_ksym_exists(scx_bpf_get_idle_cpumask_node) ? \
	scx_bpf_get_idle_cpumask_node(node) : \
	scx_bpf_get_idle_cpumask()) \

	#define __COMPAT_scx_bpf_get_idle_smtmask_node(node) \
	(bpf_ksym_exists(scx_bpf_get_idle_smtmask_node) ? \
	scx_bpf_get_idle_smtmask_node(node) : \
	scx_bpf_get_idle_smtmask())

	#define __COMPAT_scx_bpf_pick_idle_cpu_node(cpus_allowed, node, flags) \
	(bpf_ksym_exists(scx_bpf_pick_idle_cpu_node) ? \
	scx_bpf_pick_idle_cpu_node(cpus_allowed, node, flags) : \
	scx_bpf_pick_idle_cpu(cpus_allowed, flags))

	#define __COMPAT_scx_bpf_pick_any_cpu_node(cpus_allowed, node, flags) \
	(bpf_ksym_exists(scx_bpf_pick_any_cpu_node) ? \
	scx_bpf_pick_any_cpu_node(cpus_allowed, node, flags) : \
	scx_bpf_pick_any_cpu(cpus_allowed, flags))

	/*
	* v6.18: Add a helper to retrieve the current task running on a CPU.
	*
	* Keep this helper available until v6.20 for compatibility.
	*/
	static inline struct task_struct *__COMPAT_scx_bpf_cpu_curr(int cpu)
	{
	struct rq *rq;

	if (bpf_ksym_exists(scx_bpf_cpu_curr))
	return scx_bpf_cpu_curr(cpu);

	rq = scx_bpf_cpu_rq(cpu);

	return rq ? rq->curr : NULL;
	}

	/*
	* Define sched_ext_ops. This may be expanded to define multiple variants for
	* backward compatibility. See compat.h::SCX_OPS_LOAD/ATTACH().
	*/
	#define SCX_OPS_DEFINE(__name, ...) \
	SEC(".struct_ops.link") \
	struct sched_ext_ops __name = { \
	__VA_ARGS__, \
	};

	#endif /* __SCX_COMPAT_BPF_H */