xref: /linux/include/linux/sched/isolation.h (revision 62de6e1685269e1637a6c6684c8be58cc8d4ff38)
1 #ifndef _LINUX_SCHED_ISOLATION_H
2 #define _LINUX_SCHED_ISOLATION_H
3 
4 #include <linux/cpumask.h>
5 #include <linux/cpuset.h>
6 #include <linux/init.h>
7 #include <linux/tick.h>
8 
9 enum hk_type {
10 	HK_TYPE_DOMAIN,
11 	HK_TYPE_MANAGED_IRQ,
12 	HK_TYPE_KERNEL_NOISE,
13 	HK_TYPE_MAX,
14 
15 	/*
16 	 * The following housekeeping types are only set by the nohz_full
17 	 * boot commandline option. So they can share the same value.
18 	 */
19 	HK_TYPE_TICK    = HK_TYPE_KERNEL_NOISE,
20 	HK_TYPE_TIMER   = HK_TYPE_KERNEL_NOISE,
21 	HK_TYPE_RCU     = HK_TYPE_KERNEL_NOISE,
22 	HK_TYPE_MISC    = HK_TYPE_KERNEL_NOISE,
23 	HK_TYPE_WQ      = HK_TYPE_KERNEL_NOISE,
24 	HK_TYPE_KTHREAD = HK_TYPE_KERNEL_NOISE
25 };
26 
27 #ifdef CONFIG_CPU_ISOLATION
28 DECLARE_STATIC_KEY_FALSE(housekeeping_overridden);
29 extern int housekeeping_any_cpu(enum hk_type type);
30 extern const struct cpumask *housekeeping_cpumask(enum hk_type type);
31 extern bool housekeeping_enabled(enum hk_type type);
32 extern void housekeeping_affine(struct task_struct *t, enum hk_type type);
33 extern bool housekeeping_test_cpu(int cpu, enum hk_type type);
34 extern void __init housekeeping_init(void);
35 
36 #else
37 
38 static inline int housekeeping_any_cpu(enum hk_type type)
39 {
40 	return smp_processor_id();
41 }
42 
43 static inline const struct cpumask *housekeeping_cpumask(enum hk_type type)
44 {
45 	return cpu_possible_mask;
46 }
47 
48 static inline bool housekeeping_enabled(enum hk_type type)
49 {
50 	return false;
51 }
52 
53 static inline void housekeeping_affine(struct task_struct *t,
54 				       enum hk_type type) { }
55 
56 static inline bool housekeeping_test_cpu(int cpu, enum hk_type type)
57 {
58 	return true;
59 }
60 
61 static inline void housekeeping_init(void) { }
62 #endif /* CONFIG_CPU_ISOLATION */
63 
64 static inline bool housekeeping_cpu(int cpu, enum hk_type type)
65 {
66 #ifdef CONFIG_CPU_ISOLATION
67 	if (static_branch_unlikely(&housekeeping_overridden))
68 		return housekeeping_test_cpu(cpu, type);
69 #endif
70 	return true;
71 }
72 
73 static inline bool cpu_is_isolated(int cpu)
74 {
75 	return !housekeeping_test_cpu(cpu, HK_TYPE_DOMAIN) ||
76 	       !housekeeping_test_cpu(cpu, HK_TYPE_TICK) ||
77 	       cpuset_cpu_is_isolated(cpu);
78 }
79 
80 #endif /* _LINUX_SCHED_ISOLATION_H */
81