isolation.h

 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
 9enum 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
28DECLARE_STATIC_KEY_FALSE(housekeeping_overridden);
29extern int housekeeping_any_cpu(enum hk_type type);
30extern const struct cpumask *housekeeping_cpumask(enum hk_type type);
31extern bool housekeeping_enabled(enum hk_type type);
32extern void housekeeping_affine(struct task_struct *t, enum hk_type type);
33extern bool housekeeping_test_cpu(int cpu, enum hk_type type);
34extern void __init housekeeping_init(void);
35
36#else
37
38static inline int housekeeping_any_cpu(enum hk_type type)
39{
40	return smp_processor_id();
41}
42
43static inline const struct cpumask *housekeeping_cpumask(enum hk_type type)
44{
45	return cpu_possible_mask;
46}
47
48static inline bool housekeeping_enabled(enum hk_type type)
49{
50	return false;
51}
52
53static inline void housekeeping_affine(struct task_struct *t,
54				       enum hk_type type) { }
55
56static inline bool housekeeping_test_cpu(int cpu, enum hk_type type)
57{
58	return true;
59}
60
61static inline void housekeeping_init(void) { }
62#endif /* CONFIG_CPU_ISOLATION */
63
64static 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
73static 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 */