1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _LINUX_KCOV_H
3#define _LINUX_KCOV_H
4
5#include <linux/sched.h>
6#include <uapi/linux/kcov.h>
7
8struct task_struct;
9
10#ifdef CONFIG_KCOV
11
12enum kcov_mode {
13 /* Coverage collection is not enabled yet. */
14 KCOV_MODE_DISABLED = 0,
15 /* KCOV was initialized, but tracing mode hasn't been chosen yet. */
16 KCOV_MODE_INIT = 1,
17 /*
18 * Tracing coverage collection mode.
19 * Covered PCs are collected in a per-task buffer.
20 */
21 KCOV_MODE_TRACE_PC = 2,
22 /* Collecting comparison operands mode. */
23 KCOV_MODE_TRACE_CMP = 3,
24};
25
26#define KCOV_IN_CTXSW (1 << 30)
27
28void kcov_task_init(struct task_struct *t);
29void kcov_task_exit(struct task_struct *t);
30
31#define kcov_prepare_switch(t) \
32do { \
33 (t)->kcov_mode |= KCOV_IN_CTXSW; \
34} while (0)
35
36#define kcov_finish_switch(t) \
37do { \
38 (t)->kcov_mode &= ~KCOV_IN_CTXSW; \
39} while (0)
40
41/* See Documentation/dev-tools/kcov.rst for usage details. */
42void kcov_remote_start(u64 handle);
43void kcov_remote_stop(void);
44u64 kcov_common_handle(void);
45
46static inline void kcov_remote_start_common(u64 id)
47{
48 kcov_remote_start(kcov_remote_handle(KCOV_SUBSYSTEM_COMMON, id));
49}
50
51static inline void kcov_remote_start_usb(u64 id)
52{
53 kcov_remote_start(kcov_remote_handle(KCOV_SUBSYSTEM_USB, id));
54}
55
56/*
57 * The softirq flavor of kcov_remote_*() functions is introduced as a temporary
58 * work around for kcov's lack of nested remote coverage sections support in
59 * task context. Adding suport for nested sections is tracked in:
60 * https://bugzilla.kernel.org/show_bug.cgi?id=210337
61 */
62
63static inline void kcov_remote_start_usb_softirq(u64 id)
64{
65 if (in_serving_softirq())
66 kcov_remote_start_usb(id);
67}
68
69static inline void kcov_remote_stop_softirq(void)
70{
71 if (in_serving_softirq())
72 kcov_remote_stop();
73}
74
75#else
76
77static inline void kcov_task_init(struct task_struct *t) {}
78static inline void kcov_task_exit(struct task_struct *t) {}
79static inline void kcov_prepare_switch(struct task_struct *t) {}
80static inline void kcov_finish_switch(struct task_struct *t) {}
81static inline void kcov_remote_start(u64 handle) {}
82static inline void kcov_remote_stop(void) {}
83static inline u64 kcov_common_handle(void)
84{
85 return 0;
86}
87static inline void kcov_remote_start_common(u64 id) {}
88static inline void kcov_remote_start_usb(u64 id) {}
89static inline void kcov_remote_start_usb_softirq(u64 id) {}
90static inline void kcov_remote_stop_softirq(void) {}
91
92#endif /* CONFIG_KCOV */
93#endif /* _LINUX_KCOV_H */
94

source code of linux/include/linux/kcov.h