1/// kernel/sched/sched.h
 2/*
 3 * Helper to define a sched_class instance; each one is placed in a separate
 4 * section which is ordered by the linker script:
 5 *
 6 *   include/asm-generic/vmlinux.lds.h
 7 *
 8 * *CAREFUL* they are laid out in *REVERSE* order!!!
 9 *
10 * Also enforce alignment on the instance, not the type, to guarantee layout.
11 */
12#define DEFINE_SCHED_CLASS(name) \
13const struct sched_class name##_sched_class \
14	__aligned(__alignof__(struct sched_class)) \
15	__section("__" #name "_sched_class")
16
17/* Defined in include/asm-generic/vmlinux.lds.h */
18extern struct sched_class __sched_class_highest[];
19extern struct sched_class __sched_class_lowest[];
20
21#define for_class_range(class, _from, _to) \
22	for (class = (_from); class < (_to); class++)
23
24#define for_each_class(class) \
25	for_class_range(class, __sched_class_highest, __sched_class_lowest)
26
27#define sched_class_above(_a, _b)	((_a) < (_b))
28
29extern const struct sched_class stop_sched_class;
30extern const struct sched_class dl_sched_class;
31extern const struct sched_class rt_sched_class;
32extern const struct sched_class fair_sched_class;
33extern const struct sched_class idle_sched_class;

1# git grep -Inw DEFINE_SCHED_CLASS kernel/sched/*.c
2kernel/sched/deadline.c:2718:DEFINE_SCHED_CLASS(dl) = {
3kernel/sched/fair.c:12904:DEFINE_SCHED_CLASS(fair) = {
4kernel/sched/idle.c:478:DEFINE_SCHED_CLASS(idle) = {
5kernel/sched/rt.c:2699:DEFINE_SCHED_CLASS(rt) = {
6kernel/sched/stop_task.c:117:DEFINE_SCHED_CLASS(stop) = {

 1/// include/asm-generic/vmlinux.lds.h
 2/*
 3 * The order of the sched class addresses are important, as they are
 4 * used to determine the order of the priority of each sched class in
 5 * relation to each other.
 6 */
 7#define SCHED_DATA				\
 8	STRUCT_ALIGN();				\
 9	__sched_class_highest = .;		\
10	*(__stop_sched_class)			\
11	*(__dl_sched_class)			\
12	*(__rt_sched_class)			\
13	*(__fair_sched_class)			\
14	*(__idle_sched_class)			\
15	__sched_class_lowest = .;