1 #ifndef _LINUX_CONTEXT_TRACKING_H
2 #define _LINUX_CONTEXT_TRACKING_H
3 
4 #include <linux/sched.h>
5 #include <linux/vtime.h>
6 #include <linux/context_tracking_state.h>
7 #include <asm/ptrace.h>
8 
9 
10 #ifdef CONFIG_CONTEXT_TRACKING
11 extern void context_tracking_cpu_set(int cpu);
12 
13 extern void context_tracking_enter(enum ctx_state state);
14 extern void context_tracking_exit(enum ctx_state state);
15 extern void context_tracking_user_enter(void);
16 extern void context_tracking_user_exit(void);
17 
18 static inline void user_enter(void)
19 {
20 	if (context_tracking_is_enabled())
21 		context_tracking_user_enter();
22 
23 }
24 static inline void user_exit(void)
25 {
26 	if (context_tracking_is_enabled())
27 		context_tracking_user_exit();
28 }
29 
30 static inline enum ctx_state exception_enter(void)
31 {
32 	enum ctx_state prev_ctx;
33 
34 	if (!context_tracking_is_enabled())
35 		return 0;
36 
37 	prev_ctx = this_cpu_read(context_tracking.state);
38 	if (prev_ctx != CONTEXT_KERNEL)
39 		context_tracking_exit(prev_ctx);
40 
41 	return prev_ctx;
42 }
43 
44 static inline void exception_exit(enum ctx_state prev_ctx)
45 {
46 	if (context_tracking_is_enabled()) {
47 		if (prev_ctx != CONTEXT_KERNEL)
48 			context_tracking_enter(prev_ctx);
49 	}
50 }
51 
52 #else
53 static inline void user_enter(void) { }
54 static inline void user_exit(void) { }
55 static inline enum ctx_state exception_enter(void) { return 0; }
56 static inline void exception_exit(enum ctx_state prev_ctx) { }
57 #endif /* !CONFIG_CONTEXT_TRACKING */
58 
59 
60 #ifdef CONFIG_CONTEXT_TRACKING_FORCE
61 extern void context_tracking_init(void);
62 #else
63 static inline void context_tracking_init(void) { }
64 #endif /* CONFIG_CONTEXT_TRACKING_FORCE */
65 
66 
67 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
68 static inline void guest_enter(void)
69 {
70 	if (vtime_accounting_enabled())
71 		vtime_guest_enter(current);
72 	else
73 		current->flags |= PF_VCPU;
74 
75 	if (context_tracking_is_enabled())
76 		context_tracking_enter(CONTEXT_GUEST);
77 }
78 
79 static inline void guest_exit(void)
80 {
81 	if (context_tracking_is_enabled())
82 		context_tracking_exit(CONTEXT_GUEST);
83 
84 	if (vtime_accounting_enabled())
85 		vtime_guest_exit(current);
86 	else
87 		current->flags &= ~PF_VCPU;
88 }
89 
90 #else
91 static inline void guest_enter(void)
92 {
93 	/*
94 	 * This is running in ioctl context so its safe
95 	 * to assume that it's the stime pending cputime
96 	 * to flush.
97 	 */
98 	vtime_account_system(current);
99 	current->flags |= PF_VCPU;
100 }
101 
102 static inline void guest_exit(void)
103 {
104 	/* Flush the guest cputime we spent on the guest */
105 	vtime_account_system(current);
106 	current->flags &= ~PF_VCPU;
107 }
108 #endif /* CONFIG_VIRT_CPU_ACCOUNTING_GEN */
109 
110 #endif
111