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