blob: c78fc27418f218c3d343a4c176602a50ad563236 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
|
#ifndef _LINUX_CONTEXT_TRACKING_H
#define _LINUX_CONTEXT_TRACKING_H
#include <linux/sched.h>
#include <linux/vtime.h>
#include <linux/context_tracking_state.h>
#include <asm/ptrace.h>
#ifdef CONFIG_CONTEXT_TRACKING
extern void context_tracking_cpu_set(int cpu);
/* Called with interrupts disabled. */
extern void __context_tracking_enter(enum ctx_state state);
extern void __context_tracking_exit(enum ctx_state state);
extern void context_tracking_enter(enum ctx_state state);
extern void context_tracking_exit(enum ctx_state state);
extern void context_tracking_user_enter(void);
extern void context_tracking_user_exit(void);
static inline void user_enter(void)
{
if (context_tracking_is_enabled())
context_tracking_enter(CONTEXT_USER);
}
static inline void user_exit(void)
{
if (context_tracking_is_enabled())
context_tracking_exit(CONTEXT_USER);
}
/* Called with interrupts disabled. */
static inline void user_enter_irqoff(void)
{
if (context_tracking_is_enabled())
__context_tracking_enter(CONTEXT_USER);
}
static inline void user_exit_irqoff(void)
{
if (context_tracking_is_enabled())
__context_tracking_exit(CONTEXT_USER);
}
static inline enum ctx_state exception_enter(void)
{
enum ctx_state prev_ctx;
if (!context_tracking_is_enabled())
return 0;
prev_ctx = this_cpu_read(context_tracking.state);
if (prev_ctx != CONTEXT_KERNEL)
context_tracking_exit(prev_ctx);
return prev_ctx;
}
static inline void exception_exit(enum ctx_state prev_ctx)
{
if (context_tracking_is_enabled()) {
if (prev_ctx != CONTEXT_KERNEL)
context_tracking_enter(prev_ctx);
}
}
/**
* ct_state() - return the current context tracking state if known
*
* Returns the current cpu's context tracking state if context tracking
* is enabled. If context tracking is disabled, returns
* CONTEXT_DISABLED. This should be used primarily for debugging.
*/
static inline enum ctx_state ct_state(void)
{
return context_tracking_is_enabled() ?
this_cpu_read(context_tracking.state) : CONTEXT_DISABLED;
}
#else
static inline void user_enter(void) { }
static inline void user_exit(void) { }
static inline void user_enter_irqoff(void) { }
static inline void user_exit_irqoff(void) { }
static inline enum ctx_state exception_enter(void) { return 0; }
static inline void exception_exit(enum ctx_state prev_ctx) { }
static inline enum ctx_state ct_state(void) { return CONTEXT_DISABLED; }
#endif /* !CONFIG_CONTEXT_TRACKING */
#define CT_WARN_ON(cond) WARN_ON(context_tracking_is_enabled() && (cond))
#ifdef CONFIG_CONTEXT_TRACKING_FORCE
extern void context_tracking_init(void);
#else
static inline void context_tracking_init(void) { }
#endif /* CONFIG_CONTEXT_TRACKING_FORCE */
#ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
/* must be called with irqs disabled */
static inline void guest_enter_irqoff(void)
{
if (vtime_accounting_cpu_enabled())
vtime_guest_enter(current);
else
current->flags |= PF_VCPU;
if (context_tracking_is_enabled())
__context_tracking_enter(CONTEXT_GUEST);
/* KVM does not hold any references to rcu protected data when it
* switches CPU into a guest mode. In fact switching to a guest mode
* is very similar to exiting to userspace from rcu point of view. In
* addition CPU may stay in a guest mode for quite a long time (up to
* one time slice). Lets treat guest mode as quiescent state, just like
* we do with user-mode execution.
*/
if (!context_tracking_cpu_is_enabled())
rcu_virt_note_context_switch(smp_processor_id());
}
static inline void guest_exit_irqoff(void)
{
if (context_tracking_is_enabled())
__context_tracking_exit(CONTEXT_GUEST);
if (vtime_accounting_cpu_enabled())
vtime_guest_exit(current);
else
current->flags &= ~PF_VCPU;
}
#else
static inline void guest_enter_irqoff(void)
{
/*
* This is running in ioctl context so its safe
* to assume that it's the stime pending cputime
* to flush.
*/
vtime_account_system(current);
current->flags |= PF_VCPU;
rcu_virt_note_context_switch(smp_processor_id());
}
static inline void guest_exit_irqoff(void)
{
/* Flush the guest cputime we spent on the guest */
vtime_account_system(current);
current->flags &= ~PF_VCPU;
}
#endif /* CONFIG_VIRT_CPU_ACCOUNTING_GEN */
static inline void guest_enter(void)
{
unsigned long flags;
local_irq_save(flags);
guest_enter_irqoff();
local_irq_restore(flags);
}
static inline void guest_exit(void)
{
unsigned long flags;
local_irq_save(flags);
guest_exit_irqoff();
local_irq_restore(flags);
}
#endif
|
