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
11extern void context_tracking_cpu_set(int cpu);
12
13/* Called with interrupts disabled.  */
14extern void __context_tracking_enter(enum ctx_state state);
15extern void __context_tracking_exit(enum ctx_state state);
16
17extern void context_tracking_enter(enum ctx_state state);
18extern void context_tracking_exit(enum ctx_state state);
19extern void context_tracking_user_enter(void);
20extern void context_tracking_user_exit(void);
21
22static inline void user_enter(void)
23{
24	if (context_tracking_is_enabled())
25		context_tracking_enter(CONTEXT_USER);
26
27}
28static inline void user_exit(void)
29{
30	if (context_tracking_is_enabled())
31		context_tracking_exit(CONTEXT_USER);
32}
33
34static inline enum ctx_state exception_enter(void)
35{
36	enum ctx_state prev_ctx;
37
38	if (!context_tracking_is_enabled())
39		return 0;
40
41	prev_ctx = this_cpu_read(context_tracking.state);
42	if (prev_ctx != CONTEXT_KERNEL)
43		context_tracking_exit(prev_ctx);
44
45	return prev_ctx;
46}
47
48static inline void exception_exit(enum ctx_state prev_ctx)
49{
50	if (context_tracking_is_enabled()) {
51		if (prev_ctx != CONTEXT_KERNEL)
52			context_tracking_enter(prev_ctx);
53	}
54}
55
56
57/**
58 * ct_state() - return the current context tracking state if known
59 *
60 * Returns the current cpu's context tracking state if context tracking
61 * is enabled.  If context tracking is disabled, returns
62 * CONTEXT_DISABLED.  This should be used primarily for debugging.
63 */
64static inline enum ctx_state ct_state(void)
65{
66	return context_tracking_is_enabled() ?
67		this_cpu_read(context_tracking.state) : CONTEXT_DISABLED;
68}
69#else
70static inline void user_enter(void) { }
71static inline void user_exit(void) { }
72static inline enum ctx_state exception_enter(void) { return 0; }
73static inline void exception_exit(enum ctx_state prev_ctx) { }
74static inline enum ctx_state ct_state(void) { return CONTEXT_DISABLED; }
75#endif /* !CONFIG_CONTEXT_TRACKING */
76
77#define CT_WARN_ON(cond) WARN_ON(context_tracking_is_enabled() && (cond))
78
79#ifdef CONFIG_CONTEXT_TRACKING_FORCE
80extern void context_tracking_init(void);
81#else
82static inline void context_tracking_init(void) { }
83#endif /* CONFIG_CONTEXT_TRACKING_FORCE */
84
85
86#ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
87static inline void guest_enter(void)
88{
89	if (vtime_accounting_enabled())
90		vtime_guest_enter(current);
91	else
92		current->flags |= PF_VCPU;
93
94	if (context_tracking_is_enabled())
95		__context_tracking_enter(CONTEXT_GUEST);
96}
97
98static inline void guest_exit(void)
99{
100	if (context_tracking_is_enabled())
101		__context_tracking_exit(CONTEXT_GUEST);
102
103	if (vtime_accounting_enabled())
104		vtime_guest_exit(current);
105	else
106		current->flags &= ~PF_VCPU;
107}
108
109#else
110static inline void guest_enter(void)
111{
112	/*
113	 * This is running in ioctl context so its safe
114	 * to assume that it's the stime pending cputime
115	 * to flush.
116	 */
117	vtime_account_system(current);
118	current->flags |= PF_VCPU;
119}
120
121static inline void guest_exit(void)
122{
123	/* Flush the guest cputime we spent on the guest */
124	vtime_account_system(current);
125	current->flags &= ~PF_VCPU;
126}
127#endif /* CONFIG_VIRT_CPU_ACCOUNTING_GEN */
128
129#endif
130