xref: /linux-6.15/include/linux/hw_breakpoint.h (revision 659431fc)
1 #ifndef _LINUX_HW_BREAKPOINT_H
2 #define _LINUX_HW_BREAKPOINT_H
3 
4 enum {
5 	HW_BREAKPOINT_LEN_1 = 1,
6 	HW_BREAKPOINT_LEN_2 = 2,
7 	HW_BREAKPOINT_LEN_4 = 4,
8 	HW_BREAKPOINT_LEN_8 = 8,
9 };
10 
11 enum {
12 	HW_BREAKPOINT_R = 1,
13 	HW_BREAKPOINT_W = 2,
14 	HW_BREAKPOINT_X = 4,
15 };
16 
17 #ifdef __KERNEL__
18 
19 #include <linux/perf_event.h>
20 
21 #ifdef CONFIG_HAVE_HW_BREAKPOINT
22 
23 static inline void hw_breakpoint_init(struct perf_event_attr *attr)
24 {
25 	memset(attr, 0, sizeof(*attr));
26 
27 	attr->type = PERF_TYPE_BREAKPOINT;
28 	attr->size = sizeof(*attr);
29 	/*
30 	 * As it's for in-kernel or ptrace use, we want it to be pinned
31 	 * and to call its callback every hits.
32 	 */
33 	attr->pinned = 1;
34 	attr->sample_period = 1;
35 }
36 
37 static inline unsigned long hw_breakpoint_addr(struct perf_event *bp)
38 {
39 	return bp->attr.bp_addr;
40 }
41 
42 static inline int hw_breakpoint_type(struct perf_event *bp)
43 {
44 	return bp->attr.bp_type;
45 }
46 
47 static inline int hw_breakpoint_len(struct perf_event *bp)
48 {
49 	return bp->attr.bp_len;
50 }
51 
52 extern struct perf_event *
53 register_user_hw_breakpoint(struct perf_event_attr *attr,
54 			    perf_overflow_handler_t triggered,
55 			    struct task_struct *tsk);
56 
57 /* FIXME: only change from the attr, and don't unregister */
58 extern int
59 modify_user_hw_breakpoint(struct perf_event *bp, struct perf_event_attr *attr);
60 
61 /*
62  * Kernel breakpoints are not associated with any particular thread.
63  */
64 extern struct perf_event *
65 register_wide_hw_breakpoint_cpu(struct perf_event_attr *attr,
66 				perf_overflow_handler_t	triggered,
67 				int cpu);
68 
69 extern struct perf_event **
70 register_wide_hw_breakpoint(struct perf_event_attr *attr,
71 			    perf_overflow_handler_t triggered);
72 
73 extern int register_perf_hw_breakpoint(struct perf_event *bp);
74 extern int __register_perf_hw_breakpoint(struct perf_event *bp);
75 extern void unregister_hw_breakpoint(struct perf_event *bp);
76 extern void unregister_wide_hw_breakpoint(struct perf_event **cpu_events);
77 
78 extern int dbg_reserve_bp_slot(struct perf_event *bp);
79 extern int dbg_release_bp_slot(struct perf_event *bp);
80 extern int reserve_bp_slot(struct perf_event *bp);
81 extern void release_bp_slot(struct perf_event *bp);
82 
83 extern void flush_ptrace_hw_breakpoint(struct task_struct *tsk);
84 
85 static inline struct arch_hw_breakpoint *counter_arch_bp(struct perf_event *bp)
86 {
87 	return &bp->hw.info;
88 }
89 
90 #else /* !CONFIG_HAVE_HW_BREAKPOINT */
91 
92 static inline struct perf_event *
93 register_user_hw_breakpoint(struct perf_event_attr *attr,
94 			    perf_overflow_handler_t triggered,
95 			    struct task_struct *tsk)	{ return NULL; }
96 static inline int
97 modify_user_hw_breakpoint(struct perf_event *bp,
98 			  struct perf_event_attr *attr)	{ return -ENOSYS; }
99 static inline struct perf_event *
100 register_wide_hw_breakpoint_cpu(struct perf_event_attr *attr,
101 				perf_overflow_handler_t	 triggered,
102 				int cpu)		{ return NULL; }
103 static inline struct perf_event **
104 register_wide_hw_breakpoint(struct perf_event_attr *attr,
105 			    perf_overflow_handler_t triggered)	{ return NULL; }
106 static inline int
107 register_perf_hw_breakpoint(struct perf_event *bp)	{ return -ENOSYS; }
108 static inline int
109 __register_perf_hw_breakpoint(struct perf_event *bp) 	{ return -ENOSYS; }
110 static inline void unregister_hw_breakpoint(struct perf_event *bp)	{ }
111 static inline void
112 unregister_wide_hw_breakpoint(struct perf_event **cpu_events)		{ }
113 static inline int
114 reserve_bp_slot(struct perf_event *bp)			{return -ENOSYS; }
115 static inline void release_bp_slot(struct perf_event *bp) 		{ }
116 
117 static inline void flush_ptrace_hw_breakpoint(struct task_struct *tsk)	{ }
118 
119 static inline struct arch_hw_breakpoint *counter_arch_bp(struct perf_event *bp)
120 {
121 	return NULL;
122 }
123 
124 #endif /* CONFIG_HAVE_HW_BREAKPOINT */
125 #endif /* __KERNEL__ */
126 
127 #endif /* _LINUX_HW_BREAKPOINT_H */
128