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 int arch_reserve_bp_slot(struct perf_event *bp); 94 void arch_release_bp_slot(struct perf_event *bp); 95 void arch_unregister_hw_breakpoint(struct perf_event *bp); 96 97 extern void flush_ptrace_hw_breakpoint(struct task_struct *tsk); 98 99 static inline struct arch_hw_breakpoint *counter_arch_bp(struct perf_event *bp) 100 { 101 return &bp->hw.info; 102 } 103 104 #else /* !CONFIG_HAVE_HW_BREAKPOINT */ 105 106 static inline int __init init_hw_breakpoint(void) { return 0; } 107 108 static inline struct perf_event * 109 register_user_hw_breakpoint(struct perf_event_attr *attr, 110 perf_overflow_handler_t triggered, 111 void *context, 112 struct task_struct *tsk) { return NULL; } 113 static inline int 114 modify_user_hw_breakpoint(struct perf_event *bp, 115 struct perf_event_attr *attr) { return -ENOSYS; } 116 static inline int 117 modify_user_hw_breakpoint_check(struct perf_event *bp, struct perf_event_attr *attr, 118 bool check) { return -ENOSYS; } 119 120 static inline struct perf_event * 121 register_wide_hw_breakpoint_cpu(struct perf_event_attr *attr, 122 perf_overflow_handler_t triggered, 123 void *context, 124 int cpu) { return NULL; } 125 static inline struct perf_event * __percpu * 126 register_wide_hw_breakpoint(struct perf_event_attr *attr, 127 perf_overflow_handler_t triggered, 128 void *context) { return NULL; } 129 static inline int 130 register_perf_hw_breakpoint(struct perf_event *bp) { return -ENOSYS; } 131 static inline void unregister_hw_breakpoint(struct perf_event *bp) { } 132 static inline void 133 unregister_wide_hw_breakpoint(struct perf_event * __percpu *cpu_events) { } 134 static inline bool hw_breakpoint_is_used(void) { return false; } 135 136 static inline int 137 reserve_bp_slot(struct perf_event *bp) {return -ENOSYS; } 138 static inline void release_bp_slot(struct perf_event *bp) { } 139 140 static inline void flush_ptrace_hw_breakpoint(struct task_struct *tsk) { } 141 142 static inline struct arch_hw_breakpoint *counter_arch_bp(struct perf_event *bp) 143 { 144 return NULL; 145 } 146 147 #endif /* CONFIG_HAVE_HW_BREAKPOINT */ 148 #endif /* _LINUX_HW_BREAKPOINT_H */ 149