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