1 /* SPDX-License-Identifier: GPL-2.0 */ 2 3 #ifndef _LINUX_TRACE_EVENT_H 4 #define _LINUX_TRACE_EVENT_H 5 6 #include <linux/ring_buffer.h> 7 #include <linux/trace_seq.h> 8 #include <linux/percpu.h> 9 #include <linux/hardirq.h> 10 #include <linux/perf_event.h> 11 #include <linux/tracepoint.h> 12 13 struct trace_array; 14 struct trace_buffer; 15 struct tracer; 16 struct dentry; 17 struct bpf_prog; 18 19 const char *trace_print_flags_seq(struct trace_seq *p, const char *delim, 20 unsigned long flags, 21 const struct trace_print_flags *flag_array); 22 23 const char *trace_print_symbols_seq(struct trace_seq *p, unsigned long val, 24 const struct trace_print_flags *symbol_array); 25 26 #if BITS_PER_LONG == 32 27 const char *trace_print_flags_seq_u64(struct trace_seq *p, const char *delim, 28 unsigned long long flags, 29 const struct trace_print_flags_u64 *flag_array); 30 31 const char *trace_print_symbols_seq_u64(struct trace_seq *p, 32 unsigned long long val, 33 const struct trace_print_flags_u64 34 *symbol_array); 35 #endif 36 37 const char *trace_print_bitmask_seq(struct trace_seq *p, void *bitmask_ptr, 38 unsigned int bitmask_size); 39 40 const char *trace_print_hex_seq(struct trace_seq *p, 41 const unsigned char *buf, int len, 42 bool concatenate); 43 44 const char *trace_print_array_seq(struct trace_seq *p, 45 const void *buf, int count, 46 size_t el_size); 47 48 struct trace_iterator; 49 struct trace_event; 50 51 int trace_raw_output_prep(struct trace_iterator *iter, 52 struct trace_event *event); 53 54 /* 55 * The trace entry - the most basic unit of tracing. This is what 56 * is printed in the end as a single line in the trace output, such as: 57 * 58 * bash-15816 [01] 235.197585: idle_cpu <- irq_enter 59 */ 60 struct trace_entry { 61 unsigned short type; 62 unsigned char flags; 63 unsigned char preempt_count; 64 int pid; 65 }; 66 67 #define TRACE_EVENT_TYPE_MAX \ 68 ((1 << (sizeof(((struct trace_entry *)0)->type) * 8)) - 1) 69 70 /* 71 * Trace iterator - used by printout routines who present trace 72 * results to users and which routines might sleep, etc: 73 */ 74 struct trace_iterator { 75 struct trace_array *tr; 76 struct tracer *trace; 77 struct trace_buffer *trace_buffer; 78 void *private; 79 int cpu_file; 80 struct mutex mutex; 81 struct ring_buffer_iter **buffer_iter; 82 unsigned long iter_flags; 83 84 /* trace_seq for __print_flags() and __print_symbolic() etc. */ 85 struct trace_seq tmp_seq; 86 87 cpumask_var_t started; 88 89 /* it's true when current open file is snapshot */ 90 bool snapshot; 91 92 /* The below is zeroed out in pipe_read */ 93 struct trace_seq seq; 94 struct trace_entry *ent; 95 unsigned long lost_events; 96 int leftover; 97 int ent_size; 98 int cpu; 99 u64 ts; 100 101 loff_t pos; 102 long idx; 103 104 /* All new field here will be zeroed out in pipe_read */ 105 }; 106 107 enum trace_iter_flags { 108 TRACE_FILE_LAT_FMT = 1, 109 TRACE_FILE_ANNOTATE = 2, 110 TRACE_FILE_TIME_IN_NS = 4, 111 }; 112 113 114 typedef enum print_line_t (*trace_print_func)(struct trace_iterator *iter, 115 int flags, struct trace_event *event); 116 117 struct trace_event_functions { 118 trace_print_func trace; 119 trace_print_func raw; 120 trace_print_func hex; 121 trace_print_func binary; 122 }; 123 124 struct trace_event { 125 struct hlist_node node; 126 struct list_head list; 127 int type; 128 struct trace_event_functions *funcs; 129 }; 130 131 extern int register_trace_event(struct trace_event *event); 132 extern int unregister_trace_event(struct trace_event *event); 133 134 /* Return values for print_line callback */ 135 enum print_line_t { 136 TRACE_TYPE_PARTIAL_LINE = 0, /* Retry after flushing the seq */ 137 TRACE_TYPE_HANDLED = 1, 138 TRACE_TYPE_UNHANDLED = 2, /* Relay to other output functions */ 139 TRACE_TYPE_NO_CONSUME = 3 /* Handled but ask to not consume */ 140 }; 141 142 enum print_line_t trace_handle_return(struct trace_seq *s); 143 144 void tracing_generic_entry_update(struct trace_entry *entry, 145 unsigned long flags, 146 int pc); 147 struct trace_event_file; 148 149 struct ring_buffer_event * 150 trace_event_buffer_lock_reserve(struct ring_buffer **current_buffer, 151 struct trace_event_file *trace_file, 152 int type, unsigned long len, 153 unsigned long flags, int pc); 154 155 #define TRACE_RECORD_CMDLINE BIT(0) 156 #define TRACE_RECORD_TGID BIT(1) 157 158 void tracing_record_taskinfo(struct task_struct *task, int flags); 159 void tracing_record_taskinfo_sched_switch(struct task_struct *prev, 160 struct task_struct *next, int flags); 161 162 void tracing_record_cmdline(struct task_struct *task); 163 void tracing_record_tgid(struct task_struct *task); 164 165 int trace_output_call(struct trace_iterator *iter, char *name, char *fmt, ...); 166 167 struct event_filter; 168 169 enum trace_reg { 170 TRACE_REG_REGISTER, 171 TRACE_REG_UNREGISTER, 172 #ifdef CONFIG_PERF_EVENTS 173 TRACE_REG_PERF_REGISTER, 174 TRACE_REG_PERF_UNREGISTER, 175 TRACE_REG_PERF_OPEN, 176 TRACE_REG_PERF_CLOSE, 177 TRACE_REG_PERF_ADD, 178 TRACE_REG_PERF_DEL, 179 #endif 180 }; 181 182 struct trace_event_call; 183 184 struct trace_event_class { 185 const char *system; 186 void *probe; 187 #ifdef CONFIG_PERF_EVENTS 188 void *perf_probe; 189 #endif 190 int (*reg)(struct trace_event_call *event, 191 enum trace_reg type, void *data); 192 int (*define_fields)(struct trace_event_call *); 193 struct list_head *(*get_fields)(struct trace_event_call *); 194 struct list_head fields; 195 int (*raw_init)(struct trace_event_call *); 196 }; 197 198 extern int trace_event_reg(struct trace_event_call *event, 199 enum trace_reg type, void *data); 200 201 struct trace_event_buffer { 202 struct ring_buffer *buffer; 203 struct ring_buffer_event *event; 204 struct trace_event_file *trace_file; 205 void *entry; 206 unsigned long flags; 207 int pc; 208 }; 209 210 void *trace_event_buffer_reserve(struct trace_event_buffer *fbuffer, 211 struct trace_event_file *trace_file, 212 unsigned long len); 213 214 void trace_event_buffer_commit(struct trace_event_buffer *fbuffer); 215 216 enum { 217 TRACE_EVENT_FL_FILTERED_BIT, 218 TRACE_EVENT_FL_CAP_ANY_BIT, 219 TRACE_EVENT_FL_NO_SET_FILTER_BIT, 220 TRACE_EVENT_FL_IGNORE_ENABLE_BIT, 221 TRACE_EVENT_FL_TRACEPOINT_BIT, 222 TRACE_EVENT_FL_KPROBE_BIT, 223 TRACE_EVENT_FL_UPROBE_BIT, 224 }; 225 226 /* 227 * Event flags: 228 * FILTERED - The event has a filter attached 229 * CAP_ANY - Any user can enable for perf 230 * NO_SET_FILTER - Set when filter has error and is to be ignored 231 * IGNORE_ENABLE - For trace internal events, do not enable with debugfs file 232 * TRACEPOINT - Event is a tracepoint 233 * KPROBE - Event is a kprobe 234 * UPROBE - Event is a uprobe 235 */ 236 enum { 237 TRACE_EVENT_FL_FILTERED = (1 << TRACE_EVENT_FL_FILTERED_BIT), 238 TRACE_EVENT_FL_CAP_ANY = (1 << TRACE_EVENT_FL_CAP_ANY_BIT), 239 TRACE_EVENT_FL_NO_SET_FILTER = (1 << TRACE_EVENT_FL_NO_SET_FILTER_BIT), 240 TRACE_EVENT_FL_IGNORE_ENABLE = (1 << TRACE_EVENT_FL_IGNORE_ENABLE_BIT), 241 TRACE_EVENT_FL_TRACEPOINT = (1 << TRACE_EVENT_FL_TRACEPOINT_BIT), 242 TRACE_EVENT_FL_KPROBE = (1 << TRACE_EVENT_FL_KPROBE_BIT), 243 TRACE_EVENT_FL_UPROBE = (1 << TRACE_EVENT_FL_UPROBE_BIT), 244 }; 245 246 #define TRACE_EVENT_FL_UKPROBE (TRACE_EVENT_FL_KPROBE | TRACE_EVENT_FL_UPROBE) 247 248 struct trace_event_call { 249 struct list_head list; 250 struct trace_event_class *class; 251 union { 252 char *name; 253 /* Set TRACE_EVENT_FL_TRACEPOINT flag when using "tp" */ 254 struct tracepoint *tp; 255 }; 256 struct trace_event event; 257 char *print_fmt; 258 struct event_filter *filter; 259 void *mod; 260 void *data; 261 /* 262 * bit 0: filter_active 263 * bit 1: allow trace by non root (cap any) 264 * bit 2: failed to apply filter 265 * bit 3: trace internal event (do not enable) 266 * bit 4: Event was enabled by module 267 * bit 5: use call filter rather than file filter 268 * bit 6: Event is a tracepoint 269 */ 270 int flags; /* static flags of different events */ 271 272 #ifdef CONFIG_PERF_EVENTS 273 int perf_refcount; 274 struct hlist_head __percpu *perf_events; 275 struct bpf_prog *prog; 276 struct perf_event *bpf_prog_owner; 277 278 int (*perf_perm)(struct trace_event_call *, 279 struct perf_event *); 280 #endif 281 }; 282 283 static inline const char * 284 trace_event_name(struct trace_event_call *call) 285 { 286 if (call->flags & TRACE_EVENT_FL_TRACEPOINT) 287 return call->tp ? call->tp->name : NULL; 288 else 289 return call->name; 290 } 291 292 struct trace_array; 293 struct trace_subsystem_dir; 294 295 enum { 296 EVENT_FILE_FL_ENABLED_BIT, 297 EVENT_FILE_FL_RECORDED_CMD_BIT, 298 EVENT_FILE_FL_RECORDED_TGID_BIT, 299 EVENT_FILE_FL_FILTERED_BIT, 300 EVENT_FILE_FL_NO_SET_FILTER_BIT, 301 EVENT_FILE_FL_SOFT_MODE_BIT, 302 EVENT_FILE_FL_SOFT_DISABLED_BIT, 303 EVENT_FILE_FL_TRIGGER_MODE_BIT, 304 EVENT_FILE_FL_TRIGGER_COND_BIT, 305 EVENT_FILE_FL_PID_FILTER_BIT, 306 EVENT_FILE_FL_WAS_ENABLED_BIT, 307 }; 308 309 /* 310 * Event file flags: 311 * ENABLED - The event is enabled 312 * RECORDED_CMD - The comms should be recorded at sched_switch 313 * RECORDED_TGID - The tgids should be recorded at sched_switch 314 * FILTERED - The event has a filter attached 315 * NO_SET_FILTER - Set when filter has error and is to be ignored 316 * SOFT_MODE - The event is enabled/disabled by SOFT_DISABLED 317 * SOFT_DISABLED - When set, do not trace the event (even though its 318 * tracepoint may be enabled) 319 * TRIGGER_MODE - When set, invoke the triggers associated with the event 320 * TRIGGER_COND - When set, one or more triggers has an associated filter 321 * PID_FILTER - When set, the event is filtered based on pid 322 * WAS_ENABLED - Set when enabled to know to clear trace on module removal 323 */ 324 enum { 325 EVENT_FILE_FL_ENABLED = (1 << EVENT_FILE_FL_ENABLED_BIT), 326 EVENT_FILE_FL_RECORDED_CMD = (1 << EVENT_FILE_FL_RECORDED_CMD_BIT), 327 EVENT_FILE_FL_RECORDED_TGID = (1 << EVENT_FILE_FL_RECORDED_TGID_BIT), 328 EVENT_FILE_FL_FILTERED = (1 << EVENT_FILE_FL_FILTERED_BIT), 329 EVENT_FILE_FL_NO_SET_FILTER = (1 << EVENT_FILE_FL_NO_SET_FILTER_BIT), 330 EVENT_FILE_FL_SOFT_MODE = (1 << EVENT_FILE_FL_SOFT_MODE_BIT), 331 EVENT_FILE_FL_SOFT_DISABLED = (1 << EVENT_FILE_FL_SOFT_DISABLED_BIT), 332 EVENT_FILE_FL_TRIGGER_MODE = (1 << EVENT_FILE_FL_TRIGGER_MODE_BIT), 333 EVENT_FILE_FL_TRIGGER_COND = (1 << EVENT_FILE_FL_TRIGGER_COND_BIT), 334 EVENT_FILE_FL_PID_FILTER = (1 << EVENT_FILE_FL_PID_FILTER_BIT), 335 EVENT_FILE_FL_WAS_ENABLED = (1 << EVENT_FILE_FL_WAS_ENABLED_BIT), 336 }; 337 338 struct trace_event_file { 339 struct list_head list; 340 struct trace_event_call *event_call; 341 struct event_filter __rcu *filter; 342 struct dentry *dir; 343 struct trace_array *tr; 344 struct trace_subsystem_dir *system; 345 struct list_head triggers; 346 347 /* 348 * 32 bit flags: 349 * bit 0: enabled 350 * bit 1: enabled cmd record 351 * bit 2: enable/disable with the soft disable bit 352 * bit 3: soft disabled 353 * bit 4: trigger enabled 354 * 355 * Note: The bits must be set atomically to prevent races 356 * from other writers. Reads of flags do not need to be in 357 * sync as they occur in critical sections. But the way flags 358 * is currently used, these changes do not affect the code 359 * except that when a change is made, it may have a slight 360 * delay in propagating the changes to other CPUs due to 361 * caching and such. Which is mostly OK ;-) 362 */ 363 unsigned long flags; 364 atomic_t sm_ref; /* soft-mode reference counter */ 365 atomic_t tm_ref; /* trigger-mode reference counter */ 366 }; 367 368 #define __TRACE_EVENT_FLAGS(name, value) \ 369 static int __init trace_init_flags_##name(void) \ 370 { \ 371 event_##name.flags |= value; \ 372 return 0; \ 373 } \ 374 early_initcall(trace_init_flags_##name); 375 376 #define __TRACE_EVENT_PERF_PERM(name, expr...) \ 377 static int perf_perm_##name(struct trace_event_call *tp_event, \ 378 struct perf_event *p_event) \ 379 { \ 380 return ({ expr; }); \ 381 } \ 382 static int __init trace_init_perf_perm_##name(void) \ 383 { \ 384 event_##name.perf_perm = &perf_perm_##name; \ 385 return 0; \ 386 } \ 387 early_initcall(trace_init_perf_perm_##name); 388 389 #define PERF_MAX_TRACE_SIZE 2048 390 391 #define MAX_FILTER_STR_VAL 256 /* Should handle KSYM_SYMBOL_LEN */ 392 393 enum event_trigger_type { 394 ETT_NONE = (0), 395 ETT_TRACE_ONOFF = (1 << 0), 396 ETT_SNAPSHOT = (1 << 1), 397 ETT_STACKTRACE = (1 << 2), 398 ETT_EVENT_ENABLE = (1 << 3), 399 ETT_EVENT_HIST = (1 << 4), 400 ETT_HIST_ENABLE = (1 << 5), 401 }; 402 403 extern int filter_match_preds(struct event_filter *filter, void *rec); 404 405 extern enum event_trigger_type event_triggers_call(struct trace_event_file *file, 406 void *rec); 407 extern void event_triggers_post_call(struct trace_event_file *file, 408 enum event_trigger_type tt, 409 void *rec); 410 411 bool trace_event_ignore_this_pid(struct trace_event_file *trace_file); 412 413 /** 414 * trace_trigger_soft_disabled - do triggers and test if soft disabled 415 * @file: The file pointer of the event to test 416 * 417 * If any triggers without filters are attached to this event, they 418 * will be called here. If the event is soft disabled and has no 419 * triggers that require testing the fields, it will return true, 420 * otherwise false. 421 */ 422 static inline bool 423 trace_trigger_soft_disabled(struct trace_event_file *file) 424 { 425 unsigned long eflags = file->flags; 426 427 if (!(eflags & EVENT_FILE_FL_TRIGGER_COND)) { 428 if (eflags & EVENT_FILE_FL_TRIGGER_MODE) 429 event_triggers_call(file, NULL); 430 if (eflags & EVENT_FILE_FL_SOFT_DISABLED) 431 return true; 432 if (eflags & EVENT_FILE_FL_PID_FILTER) 433 return trace_event_ignore_this_pid(file); 434 } 435 return false; 436 } 437 438 #ifdef CONFIG_BPF_EVENTS 439 unsigned int trace_call_bpf(struct bpf_prog *prog, void *ctx); 440 #else 441 static inline unsigned int trace_call_bpf(struct bpf_prog *prog, void *ctx) 442 { 443 return 1; 444 } 445 #endif 446 447 enum { 448 FILTER_OTHER = 0, 449 FILTER_STATIC_STRING, 450 FILTER_DYN_STRING, 451 FILTER_PTR_STRING, 452 FILTER_TRACE_FN, 453 FILTER_COMM, 454 FILTER_CPU, 455 }; 456 457 extern int trace_event_raw_init(struct trace_event_call *call); 458 extern int trace_define_field(struct trace_event_call *call, const char *type, 459 const char *name, int offset, int size, 460 int is_signed, int filter_type); 461 extern int trace_add_event_call(struct trace_event_call *call); 462 extern int trace_remove_event_call(struct trace_event_call *call); 463 extern int trace_event_get_offsets(struct trace_event_call *call); 464 465 #define is_signed_type(type) (((type)(-1)) < (type)1) 466 467 int trace_set_clr_event(const char *system, const char *event, int set); 468 469 /* 470 * The double __builtin_constant_p is because gcc will give us an error 471 * if we try to allocate the static variable to fmt if it is not a 472 * constant. Even with the outer if statement optimizing out. 473 */ 474 #define event_trace_printk(ip, fmt, args...) \ 475 do { \ 476 __trace_printk_check_format(fmt, ##args); \ 477 tracing_record_cmdline(current); \ 478 if (__builtin_constant_p(fmt)) { \ 479 static const char *trace_printk_fmt \ 480 __attribute__((section("__trace_printk_fmt"))) = \ 481 __builtin_constant_p(fmt) ? fmt : NULL; \ 482 \ 483 __trace_bprintk(ip, trace_printk_fmt, ##args); \ 484 } else \ 485 __trace_printk(ip, fmt, ##args); \ 486 } while (0) 487 488 #ifdef CONFIG_PERF_EVENTS 489 struct perf_event; 490 491 DECLARE_PER_CPU(struct pt_regs, perf_trace_regs); 492 493 extern int perf_trace_init(struct perf_event *event); 494 extern void perf_trace_destroy(struct perf_event *event); 495 extern int perf_trace_add(struct perf_event *event, int flags); 496 extern void perf_trace_del(struct perf_event *event, int flags); 497 extern int ftrace_profile_set_filter(struct perf_event *event, int event_id, 498 char *filter_str); 499 extern void ftrace_profile_free_filter(struct perf_event *event); 500 void perf_trace_buf_update(void *record, u16 type); 501 void *perf_trace_buf_alloc(int size, struct pt_regs **regs, int *rctxp); 502 503 void perf_trace_run_bpf_submit(void *raw_data, int size, int rctx, 504 struct trace_event_call *call, u64 count, 505 struct pt_regs *regs, struct hlist_head *head, 506 struct task_struct *task); 507 508 static inline void 509 perf_trace_buf_submit(void *raw_data, int size, int rctx, u16 type, 510 u64 count, struct pt_regs *regs, void *head, 511 struct task_struct *task, struct perf_event *event) 512 { 513 perf_tp_event(type, count, raw_data, size, regs, head, rctx, task, event); 514 } 515 #endif 516 517 #endif /* _LINUX_TRACE_EVENT_H */ 518