diff options
Diffstat (limited to 'kernel/trace/trace_probe.h')
| -rw-r--r-- | kernel/trace/trace_probe.h | 546 |
1 files changed, 546 insertions, 0 deletions
diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h new file mode 100644 index 0000000000..850d9ecb67 --- /dev/null +++ b/kernel/trace/trace_probe.h @@ -0,0 +1,546 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Common header file for probe-based Dynamic events. + * + * This code was copied from kernel/trace/trace_kprobe.h written by + * Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> + * + * Updates to make this generic: + * Copyright (C) IBM Corporation, 2010-2011 + * Author: Srikar Dronamraju + */ + +#include <linux/seq_file.h> +#include <linux/slab.h> +#include <linux/smp.h> +#include <linux/tracefs.h> +#include <linux/types.h> +#include <linux/string.h> +#include <linux/ptrace.h> +#include <linux/perf_event.h> +#include <linux/kprobes.h> +#include <linux/stringify.h> +#include <linux/limits.h> +#include <linux/uaccess.h> +#include <linux/bitops.h> +#include <linux/btf.h> +#include <asm/bitsperlong.h> + +#include "trace.h" +#include "trace_output.h" + +#define MAX_TRACE_ARGS 128 +#define MAX_ARGSTR_LEN 63 +#define MAX_ARRAY_LEN 64 +#define MAX_ARG_NAME_LEN 32 +#define MAX_BTF_ARGS_LEN 128 +#define MAX_STRING_SIZE PATH_MAX +#define MAX_ARG_BUF_LEN (MAX_TRACE_ARGS * MAX_ARG_NAME_LEN) + +/* Reserved field names */ +#define FIELD_STRING_IP "__probe_ip" +#define FIELD_STRING_RETIP "__probe_ret_ip" +#define FIELD_STRING_FUNC "__probe_func" + +#undef DEFINE_FIELD +#define DEFINE_FIELD(type, item, name, is_signed) \ + do { \ + ret = trace_define_field(event_call, #type, name, \ + offsetof(typeof(field), item), \ + sizeof(field.item), is_signed, \ + FILTER_OTHER); \ + if (ret) \ + return ret; \ + } while (0) + + +/* Flags for trace_probe */ +#define TP_FLAG_TRACE 1 +#define TP_FLAG_PROFILE 2 + +/* data_loc: data location, compatible with u32 */ +#define make_data_loc(len, offs) \ + (((u32)(len) << 16) | ((u32)(offs) & 0xffff)) +#define get_loc_len(dl) ((u32)(dl) >> 16) +#define get_loc_offs(dl) ((u32)(dl) & 0xffff) + +static nokprobe_inline void *get_loc_data(u32 *dl, void *ent) +{ + return (u8 *)ent + get_loc_offs(*dl); +} + +static nokprobe_inline u32 update_data_loc(u32 loc, int consumed) +{ + u32 maxlen = get_loc_len(loc); + u32 offset = get_loc_offs(loc); + + return make_data_loc(maxlen - consumed, offset + consumed); +} + +/* Printing function type */ +typedef int (*print_type_func_t)(struct trace_seq *, void *, void *); + +enum fetch_op { + FETCH_OP_NOP = 0, + // Stage 1 (load) ops + FETCH_OP_REG, /* Register : .param = offset */ + FETCH_OP_STACK, /* Stack : .param = index */ + FETCH_OP_STACKP, /* Stack pointer */ + FETCH_OP_RETVAL, /* Return value */ + FETCH_OP_IMM, /* Immediate : .immediate */ + FETCH_OP_COMM, /* Current comm */ + FETCH_OP_ARG, /* Function argument : .param */ + FETCH_OP_FOFFS, /* File offset: .immediate */ + FETCH_OP_DATA, /* Allocated data: .data */ + // Stage 2 (dereference) op + FETCH_OP_DEREF, /* Dereference: .offset */ + FETCH_OP_UDEREF, /* User-space Dereference: .offset */ + // Stage 3 (store) ops + FETCH_OP_ST_RAW, /* Raw: .size */ + FETCH_OP_ST_MEM, /* Mem: .offset, .size */ + FETCH_OP_ST_UMEM, /* Mem: .offset, .size */ + FETCH_OP_ST_STRING, /* String: .offset, .size */ + FETCH_OP_ST_USTRING, /* User String: .offset, .size */ + FETCH_OP_ST_SYMSTR, /* Kernel Symbol String: .offset, .size */ + // Stage 4 (modify) op + FETCH_OP_MOD_BF, /* Bitfield: .basesize, .lshift, .rshift */ + // Stage 5 (loop) op + FETCH_OP_LP_ARRAY, /* Array: .param = loop count */ + FETCH_OP_TP_ARG, /* Trace Point argument */ + FETCH_OP_END, + FETCH_NOP_SYMBOL, /* Unresolved Symbol holder */ +}; + +struct fetch_insn { + enum fetch_op op; + union { + unsigned int param; + struct { + unsigned int size; + int offset; + }; + struct { + unsigned char basesize; + unsigned char lshift; + unsigned char rshift; + }; + unsigned long immediate; + void *data; + }; +}; + +/* fetch + deref*N + store + mod + end <= 16, this allows N=12, enough */ +#define FETCH_INSN_MAX 16 +#define FETCH_TOKEN_COMM (-ECOMM) + +/* Fetch type information table */ +struct fetch_type { + const char *name; /* Name of type */ + size_t size; /* Byte size of type */ + bool is_signed; /* Signed flag */ + bool is_string; /* String flag */ + print_type_func_t print; /* Print functions */ + const char *fmt; /* Format string */ + const char *fmttype; /* Name in format file */ +}; + +/* For defining macros, define string/string_size types */ +typedef u32 string; +typedef u32 string_size; + +#define PRINT_TYPE_FUNC_NAME(type) print_type_##type +#define PRINT_TYPE_FMT_NAME(type) print_type_format_##type + +/* Printing in basic type function template */ +#define DECLARE_BASIC_PRINT_TYPE_FUNC(type) \ +int PRINT_TYPE_FUNC_NAME(type)(struct trace_seq *s, void *data, void *ent);\ +extern const char PRINT_TYPE_FMT_NAME(type)[] + +DECLARE_BASIC_PRINT_TYPE_FUNC(u8); +DECLARE_BASIC_PRINT_TYPE_FUNC(u16); +DECLARE_BASIC_PRINT_TYPE_FUNC(u32); +DECLARE_BASIC_PRINT_TYPE_FUNC(u64); +DECLARE_BASIC_PRINT_TYPE_FUNC(s8); +DECLARE_BASIC_PRINT_TYPE_FUNC(s16); +DECLARE_BASIC_PRINT_TYPE_FUNC(s32); +DECLARE_BASIC_PRINT_TYPE_FUNC(s64); +DECLARE_BASIC_PRINT_TYPE_FUNC(x8); +DECLARE_BASIC_PRINT_TYPE_FUNC(x16); +DECLARE_BASIC_PRINT_TYPE_FUNC(x32); +DECLARE_BASIC_PRINT_TYPE_FUNC(x64); + +DECLARE_BASIC_PRINT_TYPE_FUNC(char); +DECLARE_BASIC_PRINT_TYPE_FUNC(string); +DECLARE_BASIC_PRINT_TYPE_FUNC(symbol); + +/* Default (unsigned long) fetch type */ +#define __DEFAULT_FETCH_TYPE(t) x##t +#define _DEFAULT_FETCH_TYPE(t) __DEFAULT_FETCH_TYPE(t) +#define DEFAULT_FETCH_TYPE _DEFAULT_FETCH_TYPE(BITS_PER_LONG) +#define DEFAULT_FETCH_TYPE_STR __stringify(DEFAULT_FETCH_TYPE) + +#define __ADDR_FETCH_TYPE(t) u##t +#define _ADDR_FETCH_TYPE(t) __ADDR_FETCH_TYPE(t) +#define ADDR_FETCH_TYPE _ADDR_FETCH_TYPE(BITS_PER_LONG) + +#define __ASSIGN_FETCH_TYPE(_name, ptype, ftype, _size, sign, str, _fmttype) \ + {.name = _name, \ + .size = _size, \ + .is_signed = (bool)sign, \ + .is_string = (bool)str, \ + .print = PRINT_TYPE_FUNC_NAME(ptype), \ + .fmt = PRINT_TYPE_FMT_NAME(ptype), \ + .fmttype = _fmttype, \ + } + +/* Non string types can use these macros */ +#define _ASSIGN_FETCH_TYPE(_name, ptype, ftype, _size, sign, _fmttype) \ + __ASSIGN_FETCH_TYPE(_name, ptype, ftype, _size, sign, 0, #_fmttype) +#define ASSIGN_FETCH_TYPE(ptype, ftype, sign) \ + _ASSIGN_FETCH_TYPE(#ptype, ptype, ftype, sizeof(ftype), sign, ptype) + +/* If ptype is an alias of atype, use this macro (show atype in format) */ +#define ASSIGN_FETCH_TYPE_ALIAS(ptype, atype, ftype, sign) \ + _ASSIGN_FETCH_TYPE(#ptype, ptype, ftype, sizeof(ftype), sign, atype) + +#define ASSIGN_FETCH_TYPE_END {} +#define MAX_ARRAY_LEN 64 + +#ifdef CONFIG_KPROBE_EVENTS +bool trace_kprobe_on_func_entry(struct trace_event_call *call); +bool trace_kprobe_error_injectable(struct trace_event_call *call); +#else +static inline bool trace_kprobe_on_func_entry(struct trace_event_call *call) +{ + return false; +} + +static inline bool trace_kprobe_error_injectable(struct trace_event_call *call) +{ + return false; +} +#endif /* CONFIG_KPROBE_EVENTS */ + +struct probe_arg { + struct fetch_insn *code; + bool dynamic;/* Dynamic array (string) is used */ + unsigned int offset; /* Offset from argument entry */ + unsigned int count; /* Array count */ + const char *name; /* Name of this argument */ + const char *comm; /* Command of this argument */ + char *fmt; /* Format string if needed */ + const struct fetch_type *type; /* Type of this argument */ +}; + +struct trace_uprobe_filter { + rwlock_t rwlock; + int nr_systemwide; + struct list_head perf_events; +}; + +/* Event call and class holder */ +struct trace_probe_event { + unsigned int flags; /* For TP_FLAG_* */ + struct trace_event_class class; + struct trace_event_call call; + struct list_head files; + struct list_head probes; + struct trace_uprobe_filter filter[]; +}; + +struct trace_probe { + struct list_head list; + struct trace_probe_event *event; + ssize_t size; /* trace entry size */ + unsigned int nr_args; + struct probe_arg args[]; +}; + +struct event_file_link { + struct trace_event_file *file; + struct list_head list; +}; + +static inline bool trace_probe_test_flag(struct trace_probe *tp, + unsigned int flag) +{ + return !!(tp->event->flags & flag); +} + +static inline void trace_probe_set_flag(struct trace_probe *tp, + unsigned int flag) +{ + tp->event->flags |= flag; +} + +static inline void trace_probe_clear_flag(struct trace_probe *tp, + unsigned int flag) +{ + tp->event->flags &= ~flag; +} + +static inline bool trace_probe_is_enabled(struct trace_probe *tp) +{ + return trace_probe_test_flag(tp, TP_FLAG_TRACE | TP_FLAG_PROFILE); +} + +static inline const char *trace_probe_name(struct trace_probe *tp) +{ + return trace_event_name(&tp->event->call); +} + +static inline const char *trace_probe_group_name(struct trace_probe *tp) +{ + return tp->event->call.class->system; +} + +static inline struct trace_event_call * + trace_probe_event_call(struct trace_probe *tp) +{ + return &tp->event->call; +} + +static inline struct trace_probe_event * +trace_probe_event_from_call(struct trace_event_call *event_call) +{ + return container_of(event_call, struct trace_probe_event, call); +} + +static inline struct trace_probe * +trace_probe_primary_from_call(struct trace_event_call *call) +{ + struct trace_probe_event *tpe = trace_probe_event_from_call(call); + + return list_first_entry_or_null(&tpe->probes, struct trace_probe, list); +} + +static inline struct list_head *trace_probe_probe_list(struct trace_probe *tp) +{ + return &tp->event->probes; +} + +static inline bool trace_probe_has_sibling(struct trace_probe *tp) +{ + struct list_head *list = trace_probe_probe_list(tp); + + return !list_empty(list) && !list_is_singular(list); +} + +static inline int trace_probe_unregister_event_call(struct trace_probe *tp) +{ + /* tp->event is unregistered in trace_remove_event_call() */ + return trace_remove_event_call(&tp->event->call); +} + +static inline bool trace_probe_has_single_file(struct trace_probe *tp) +{ + return !!list_is_singular(&tp->event->files); +} + +int trace_probe_init(struct trace_probe *tp, const char *event, + const char *group, bool alloc_filter); +void trace_probe_cleanup(struct trace_probe *tp); +int trace_probe_append(struct trace_probe *tp, struct trace_probe *to); +void trace_probe_unlink(struct trace_probe *tp); +int trace_probe_register_event_call(struct trace_probe *tp); +int trace_probe_add_file(struct trace_probe *tp, struct trace_event_file *file); +int trace_probe_remove_file(struct trace_probe *tp, + struct trace_event_file *file); +struct event_file_link *trace_probe_get_file_link(struct trace_probe *tp, + struct trace_event_file *file); +int trace_probe_compare_arg_type(struct trace_probe *a, struct trace_probe *b); +bool trace_probe_match_command_args(struct trace_probe *tp, + int argc, const char **argv); +int trace_probe_create(const char *raw_command, int (*createfn)(int, const char **)); +int trace_probe_print_args(struct trace_seq *s, struct probe_arg *args, int nr_args, + u8 *data, void *field); + +#define trace_probe_for_each_link(pos, tp) \ + list_for_each_entry(pos, &(tp)->event->files, list) +#define trace_probe_for_each_link_rcu(pos, tp) \ + list_for_each_entry_rcu(pos, &(tp)->event->files, list) + +/* + * The flags used for parsing trace_probe arguments. + * TPARG_FL_RETURN, TPARG_FL_FENTRY and TPARG_FL_TEVENT are mutually exclusive. + * TPARG_FL_KERNEL and TPARG_FL_USER are also mutually exclusive. + * TPARG_FL_FPROBE and TPARG_FL_TPOINT are optional but it should be with + * TPARG_FL_KERNEL. + */ +#define TPARG_FL_RETURN BIT(0) +#define TPARG_FL_KERNEL BIT(1) +#define TPARG_FL_FENTRY BIT(2) +#define TPARG_FL_TEVENT BIT(3) +#define TPARG_FL_USER BIT(4) +#define TPARG_FL_FPROBE BIT(5) +#define TPARG_FL_TPOINT BIT(6) +#define TPARG_FL_LOC_MASK GENMASK(4, 0) + +static inline bool tparg_is_function_entry(unsigned int flags) +{ + return (flags & TPARG_FL_LOC_MASK) == (TPARG_FL_KERNEL | TPARG_FL_FENTRY); +} + +struct traceprobe_parse_context { + struct trace_event_call *event; + /* BTF related parameters */ + const char *funcname; /* Function name in BTF */ + const struct btf_type *proto; /* Prototype of the function */ + const struct btf_param *params; /* Parameter of the function */ + s32 nr_params; /* The number of the parameters */ + struct btf *btf; /* The BTF to be used */ + const struct btf_type *last_type; /* Saved type */ + u32 last_bitoffs; /* Saved bitoffs */ + u32 last_bitsize; /* Saved bitsize */ + unsigned int flags; + int offset; +}; + +extern int traceprobe_parse_probe_arg(struct trace_probe *tp, int i, + const char *argv, + struct traceprobe_parse_context *ctx); +const char **traceprobe_expand_meta_args(int argc, const char *argv[], + int *new_argc, char *buf, int bufsize, + struct traceprobe_parse_context *ctx); + +extern int traceprobe_update_arg(struct probe_arg *arg); +extern void traceprobe_free_probe_arg(struct probe_arg *arg); + +/* + * If either traceprobe_parse_probe_arg() or traceprobe_expand_meta_args() is called, + * this MUST be called for clean up the context and return a resource. + */ +void traceprobe_finish_parse(struct traceprobe_parse_context *ctx); + +extern int traceprobe_split_symbol_offset(char *symbol, long *offset); +int traceprobe_parse_event_name(const char **pevent, const char **pgroup, + char *buf, int offset); + +enum probe_print_type { + PROBE_PRINT_NORMAL, + PROBE_PRINT_RETURN, + PROBE_PRINT_EVENT, +}; + +extern int traceprobe_set_print_fmt(struct trace_probe *tp, enum probe_print_type ptype); + +#ifdef CONFIG_PERF_EVENTS +extern struct trace_event_call * +create_local_trace_kprobe(char *func, void *addr, unsigned long offs, + bool is_return); +extern void destroy_local_trace_kprobe(struct trace_event_call *event_call); + +extern struct trace_event_call * +create_local_trace_uprobe(char *name, unsigned long offs, + unsigned long ref_ctr_offset, bool is_return); +extern void destroy_local_trace_uprobe(struct trace_event_call *event_call); +#endif +extern int traceprobe_define_arg_fields(struct trace_event_call *event_call, + size_t offset, struct trace_probe *tp); + +#undef ERRORS +#define ERRORS \ + C(FILE_NOT_FOUND, "Failed to find the given file"), \ + C(NO_REGULAR_FILE, "Not a regular file"), \ + C(BAD_REFCNT, "Invalid reference counter offset"), \ + C(REFCNT_OPEN_BRACE, "Reference counter brace is not closed"), \ + C(BAD_REFCNT_SUFFIX, "Reference counter has wrong suffix"), \ + C(BAD_UPROBE_OFFS, "Invalid uprobe offset"), \ + C(BAD_MAXACT_TYPE, "Maxactive is only for function exit"), \ + C(BAD_MAXACT, "Invalid maxactive number"), \ + C(MAXACT_TOO_BIG, "Maxactive is too big"), \ + C(BAD_PROBE_ADDR, "Invalid probed address or symbol"), \ + C(NON_UNIQ_SYMBOL, "The symbol is not unique"), \ + C(BAD_RETPROBE, "Retprobe address must be an function entry"), \ + C(NO_TRACEPOINT, "Tracepoint is not found"), \ + C(BAD_ADDR_SUFFIX, "Invalid probed address suffix"), \ + C(NO_GROUP_NAME, "Group name is not specified"), \ + C(GROUP_TOO_LONG, "Group name is too long"), \ + C(BAD_GROUP_NAME, "Group name must follow the same rules as C identifiers"), \ + C(NO_EVENT_NAME, "Event name is not specified"), \ + C(EVENT_TOO_LONG, "Event name is too long"), \ + C(BAD_EVENT_NAME, "Event name must follow the same rules as C identifiers"), \ + C(EVENT_EXIST, "Given group/event name is already used by another event"), \ + C(RETVAL_ON_PROBE, "$retval is not available on probe"), \ + C(NO_RETVAL, "This function returns 'void' type"), \ + C(BAD_STACK_NUM, "Invalid stack number"), \ + C(BAD_ARG_NUM, "Invalid argument number"), \ + C(BAD_VAR, "Invalid $-valiable specified"), \ + C(BAD_REG_NAME, "Invalid register name"), \ + C(BAD_MEM_ADDR, "Invalid memory address"), \ + C(BAD_IMM, "Invalid immediate value"), \ + C(IMMSTR_NO_CLOSE, "String is not closed with '\"'"), \ + C(FILE_ON_KPROBE, "File offset is not available with kprobe"), \ + C(BAD_FILE_OFFS, "Invalid file offset value"), \ + C(SYM_ON_UPROBE, "Symbol is not available with uprobe"), \ + C(TOO_MANY_OPS, "Dereference is too much nested"), \ + C(DEREF_NEED_BRACE, "Dereference needs a brace"), \ + C(BAD_DEREF_OFFS, "Invalid dereference offset"), \ + C(DEREF_OPEN_BRACE, "Dereference brace is not closed"), \ + C(COMM_CANT_DEREF, "$comm can not be dereferenced"), \ + C(BAD_FETCH_ARG, "Invalid fetch argument"), \ + C(ARRAY_NO_CLOSE, "Array is not closed"), \ + C(BAD_ARRAY_SUFFIX, "Array has wrong suffix"), \ + C(BAD_ARRAY_NUM, "Invalid array size"), \ + C(ARRAY_TOO_BIG, "Array number is too big"), \ + C(BAD_TYPE, "Unknown type is specified"), \ + C(BAD_STRING, "String accepts only memory argument"), \ + C(BAD_SYMSTRING, "Symbol String doesn't accept data/userdata"), \ + C(BAD_BITFIELD, "Invalid bitfield"), \ + C(ARG_NAME_TOO_LONG, "Argument name is too long"), \ + C(NO_ARG_NAME, "Argument name is not specified"), \ + C(BAD_ARG_NAME, "Argument name must follow the same rules as C identifiers"), \ + C(USED_ARG_NAME, "This argument name is already used"), \ + C(ARG_TOO_LONG, "Argument expression is too long"), \ + C(NO_ARG_BODY, "No argument expression"), \ + C(BAD_INSN_BNDRY, "Probe point is not an instruction boundary"),\ + C(FAIL_REG_PROBE, "Failed to register probe event"),\ + C(DIFF_PROBE_TYPE, "Probe type is different from existing probe"),\ + C(DIFF_ARG_TYPE, "Argument type or name is different from existing probe"),\ + C(SAME_PROBE, "There is already the exact same probe event"),\ + C(NO_EVENT_INFO, "This requires both group and event name to attach"),\ + C(BAD_ATTACH_EVENT, "Attached event does not exist"),\ + C(BAD_ATTACH_ARG, "Attached event does not have this field"),\ + C(NO_EP_FILTER, "No filter rule after 'if'"), \ + C(NOSUP_BTFARG, "BTF is not available or not supported"), \ + C(NO_BTFARG, "This variable is not found at this probe point"),\ + C(NO_BTF_ENTRY, "No BTF entry for this probe point"), \ + C(BAD_VAR_ARGS, "$arg* must be an independent parameter without name etc."),\ + C(NOFENTRY_ARGS, "$arg* can be used only on function entry"), \ + C(DOUBLE_ARGS, "$arg* can be used only once in the parameters"), \ + C(ARGS_2LONG, "$arg* failed because the argument list is too long"), \ + C(ARGIDX_2BIG, "$argN index is too big"), \ + C(NO_PTR_STRCT, "This is not a pointer to union/structure."), \ + C(NOSUP_DAT_ARG, "Non pointer structure/union argument is not supported."),\ + C(BAD_HYPHEN, "Failed to parse single hyphen. Forgot '>'?"), \ + C(NO_BTF_FIELD, "This field is not found."), \ + C(BAD_BTF_TID, "Failed to get BTF type info."),\ + C(BAD_TYPE4STR, "This type does not fit for string."), + +#undef C +#define C(a, b) TP_ERR_##a + +/* Define TP_ERR_ */ +enum { ERRORS }; + +/* Error text is defined in trace_probe.c */ + +struct trace_probe_log { + const char *subsystem; + const char **argv; + int argc; + int index; +}; + +void trace_probe_log_init(const char *subsystem, int argc, const char **argv); +void trace_probe_log_set_index(int index); +void trace_probe_log_clear(void); +void __trace_probe_log_err(int offset, int err); + +#define trace_probe_log_err(offs, err) \ + __trace_probe_log_err(offs, TP_ERR_##err) + +struct uprobe_dispatch_data { + struct trace_uprobe *tu; + unsigned long bp_addr; +}; |