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
|
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_KCOV_H
#define _LINUX_KCOV_H
#include <linux/sched.h>
#include <uapi/linux/kcov.h>
struct task_struct;
#ifdef CONFIG_KCOV
enum kcov_mode {
/* Coverage collection is not enabled yet. */
KCOV_MODE_DISABLED = 0,
/* KCOV was initialized, but tracing mode hasn't been chosen yet. */
KCOV_MODE_INIT = 1,
/*
* Tracing coverage collection mode.
* Covered PCs are collected in a per-task buffer.
*/
KCOV_MODE_TRACE_PC = 2,
/* Collecting comparison operands mode. */
KCOV_MODE_TRACE_CMP = 3,
/* The process owns a KCOV remote reference. */
KCOV_MODE_REMOTE = 4,
};
#define KCOV_IN_CTXSW (1 << 30)
void kcov_task_init(struct task_struct *t);
void kcov_task_exit(struct task_struct *t);
#define kcov_prepare_switch(t) \
do { \
(t)->kcov_mode |= KCOV_IN_CTXSW; \
} while (0)
#define kcov_finish_switch(t) \
do { \
(t)->kcov_mode &= ~KCOV_IN_CTXSW; \
} while (0)
/* See Documentation/dev-tools/kcov.rst for usage details. */
void kcov_remote_start(u64 handle);
void kcov_remote_stop(void);
u64 kcov_common_handle(void);
static inline void kcov_remote_start_common(u64 id)
{
kcov_remote_start(kcov_remote_handle(KCOV_SUBSYSTEM_COMMON, id));
}
static inline void kcov_remote_start_usb(u64 id)
{
kcov_remote_start(kcov_remote_handle(KCOV_SUBSYSTEM_USB, id));
}
/*
* The softirq flavor of kcov_remote_*() functions is introduced as a temporary
* workaround for KCOV's lack of nested remote coverage sections support.
*
* Adding support is tracked in https://bugzilla.kernel.org/show_bug.cgi?id=210337.
*
* kcov_remote_start_usb_softirq():
*
* 1. Only collects coverage when called in the softirq context. This allows
* avoiding nested remote coverage collection sections in the task context.
* For example, USB/IP calls usb_hcd_giveback_urb() in the task context
* within an existing remote coverage collection section. Thus, KCOV should
* not attempt to start collecting coverage within the coverage collection
* section in __usb_hcd_giveback_urb() in this case.
*
* 2. Disables interrupts for the duration of the coverage collection section.
* This allows avoiding nested remote coverage collection sections in the
* softirq context (a softirq might occur during the execution of a work in
* the BH workqueue, which runs with in_serving_softirq() > 0).
* For example, usb_giveback_urb_bh() runs in the BH workqueue with
* interrupts enabled, so __usb_hcd_giveback_urb() might be interrupted in
* the middle of its remote coverage collection section, and the interrupt
* handler might invoke __usb_hcd_giveback_urb() again.
*/
static inline unsigned long kcov_remote_start_usb_softirq(u64 id)
{
unsigned long flags = 0;
if (in_serving_softirq()) {
local_irq_save(flags);
kcov_remote_start_usb(id);
}
return flags;
}
static inline void kcov_remote_stop_softirq(unsigned long flags)
{
if (in_serving_softirq()) {
kcov_remote_stop();
local_irq_restore(flags);
}
}
#ifdef CONFIG_64BIT
typedef unsigned long kcov_u64;
#else
typedef unsigned long long kcov_u64;
#endif
void __sanitizer_cov_trace_pc(void);
void __sanitizer_cov_trace_cmp1(u8 arg1, u8 arg2);
void __sanitizer_cov_trace_cmp2(u16 arg1, u16 arg2);
void __sanitizer_cov_trace_cmp4(u32 arg1, u32 arg2);
void __sanitizer_cov_trace_cmp8(kcov_u64 arg1, kcov_u64 arg2);
void __sanitizer_cov_trace_const_cmp1(u8 arg1, u8 arg2);
void __sanitizer_cov_trace_const_cmp2(u16 arg1, u16 arg2);
void __sanitizer_cov_trace_const_cmp4(u32 arg1, u32 arg2);
void __sanitizer_cov_trace_const_cmp8(kcov_u64 arg1, kcov_u64 arg2);
void __sanitizer_cov_trace_switch(kcov_u64 val, void *cases);
#else
static inline void kcov_task_init(struct task_struct *t) {}
static inline void kcov_task_exit(struct task_struct *t) {}
static inline void kcov_prepare_switch(struct task_struct *t) {}
static inline void kcov_finish_switch(struct task_struct *t) {}
static inline void kcov_remote_start(u64 handle) {}
static inline void kcov_remote_stop(void) {}
static inline u64 kcov_common_handle(void)
{
return 0;
}
static inline void kcov_remote_start_common(u64 id) {}
static inline void kcov_remote_start_usb(u64 id) {}
static inline unsigned long kcov_remote_start_usb_softirq(u64 id)
{
return 0;
}
static inline void kcov_remote_stop_softirq(unsigned long flags) {}
#endif /* CONFIG_KCOV */
#endif /* _LINUX_KCOV_H */
|
