1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _LINUX_HW_BREAKPOINT_H 3 #define _LINUX_HW_BREAKPOINT_H 4 5 #include <linux/perf_event.h> 6 #include <uapi/linux/hw_breakpoint.h> 7 8 #ifdef CONFIG_HAVE_HW_BREAKPOINT 9 10 enum bp_type_idx { 11 TYPE_INST = 0, 12 #if defined(CONFIG_HAVE_MIXED_BREAKPOINTS_REGS) 13 TYPE_DATA = 0, 14 #else 15 TYPE_DATA = 1, 16 #endif 17 TYPE_MAX 18 }; 19 20 extern int __init init_hw_breakpoint(void); 21 22 static inline void hw_breakpoint_init(struct perf_event_attr *attr) 23 { 24 memset(attr, 0, sizeof(*attr)); 25 26 attr->type = PERF_TYPE_BREAKPOINT; 27 attr->size = sizeof(*attr); 28 /* 29 * As it's for in-kernel or ptrace use, we want it to be pinned 30 * and to call its callback every hits. 31 */ 32 attr->pinned = 1; 33 attr->sample_period = 1; 34 } 35 36 static inline void ptrace_breakpoint_init(struct perf_event_attr *attr) 37 { 38 hw_breakpoint_init(attr); 39 attr->exclude_kernel = 1; 40 } 41 42 static inline unsigned long hw_breakpoint_addr(struct perf_event *bp) 43 { 44 return bp->attr.bp_addr; 45 } 46 47 static inline int hw_breakpoint_type(struct perf_event *bp) 48 { 49 return bp->attr.bp_type; 50 } 51 52 static inline unsigned long hw_breakpoint_len(struct perf_event *bp) 53 { 54 return bp->attr.bp_len; 55 } 56 57 extern struct perf_event * 58 register_user_hw_breakpoint(struct perf_event_attr *attr, 59 perf_overflow_handler_t triggered, 60 void *context, 61 struct task_struct *tsk); 62 63 /* FIXME: only change from the attr, and don't unregister */ 64 extern int 65 modify_user_hw_breakpoint(struct perf_event *bp, struct perf_event_attr *attr); 66 extern int 67 modify_user_hw_breakpoint_check(struct perf_event *bp, struct perf_event_attr *attr, 68 bool check); 69 70 /* 71 * Kernel breakpoints are not associated with any particular thread. 72 */ 73 extern struct perf_event * 74 register_wide_hw_breakpoint_cpu(struct perf_event_attr *attr, 75 perf_overflow_handler_t triggered, 76 void *context, 77 int cpu); 78 79 extern struct perf_event * __percpu * 80 register_wide_hw_breakpoint(struct perf_event_attr *attr, 81 perf_overflow_handler_t triggered, 82 void *context); 83 84 extern int register_perf_hw_breakpoint(struct perf_event *bp); 85 extern void unregister_hw_breakpoint(struct perf_event *bp); 86 extern void unregister_wide_hw_breakpoint(struct perf_event * __percpu *cpu_events); 87 extern bool hw_breakpoint_is_used(void); 88 89 extern int dbg_reserve_bp_slot(struct perf_event *bp); 90 extern int dbg_release_bp_slot(struct perf_event *bp); 91 extern int reserve_bp_slot(struct perf_event *bp); 92 extern void release_bp_slot(struct perf_event *bp); 93 94 extern void flush_ptrace_hw_breakpoint(struct task_struct *tsk); 95 96 static inline struct arch_hw_breakpoint *counter_arch_bp(struct perf_event *bp) 97 { 98 return &bp->hw.info; 99 } 100 101 #else /* !CONFIG_HAVE_HW_BREAKPOINT */ 102 103 static inline int __init init_hw_breakpoint(void) { return 0; } 104 105 static inline struct perf_event * 106 register_user_hw_breakpoint(struct perf_event_attr *attr, 107 perf_overflow_handler_t triggered, 108 void *context, 109 struct task_struct *tsk) { return NULL; } 110 static inline int 111 modify_user_hw_breakpoint(struct perf_event *bp, 112 struct perf_event_attr *attr) { return -ENOSYS; } 113 static inline int 114 modify_user_hw_breakpoint_check(struct perf_event *bp, struct perf_event_attr *attr, 115 bool check) { return -ENOSYS; } 116 117 static inline struct perf_event * 118 register_wide_hw_breakpoint_cpu(struct perf_event_attr *attr, 119 perf_overflow_handler_t triggered, 120 void *context, 121 int cpu) { return NULL; } 122 static inline struct perf_event * __percpu * 123 register_wide_hw_breakpoint(struct perf_event_attr *attr, 124 perf_overflow_handler_t triggered, 125 void *context) { return NULL; } 126 static inline int 127 register_perf_hw_breakpoint(struct perf_event *bp) { return -ENOSYS; } 128 static inline void unregister_hw_breakpoint(struct perf_event *bp) { } 129 static inline void 130 unregister_wide_hw_breakpoint(struct perf_event * __percpu *cpu_events) { } 131 static inline bool hw_breakpoint_is_used(void) { return false; } 132 133 static inline int 134 reserve_bp_slot(struct perf_event *bp) {return -ENOSYS; } 135 static inline void release_bp_slot(struct perf_event *bp) { } 136 137 static inline void flush_ptrace_hw_breakpoint(struct task_struct *tsk) { } 138 139 static inline struct arch_hw_breakpoint *counter_arch_bp(struct perf_event *bp) 140 { 141 return NULL; 142 } 143 144 #endif /* CONFIG_HAVE_HW_BREAKPOINT */ 145 #endif /* _LINUX_HW_BREAKPOINT_H */ 146