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_symbols_seq_u64(struct trace_seq *p, 27 unsigned long long val, 28 const struct trace_print_flags_u64 29 *symbol_array); 30 #endif 31 32 const char *trace_print_bitmask_seq(struct trace_seq *p, void *bitmask_ptr, 33 unsigned int bitmask_size); 34 35 const char *trace_print_hex_seq(struct trace_seq *p, 36 const unsigned char *buf, int len, 37 bool spacing); 38 39 const char *trace_print_array_seq(struct trace_seq *p, 40 const void *buf, int count, 41 size_t el_size); 42 43 struct trace_iterator; 44 struct trace_event; 45 46 int trace_raw_output_prep(struct trace_iterator *iter, 47 struct trace_event *event); 48 49 /* 50 * The trace entry - the most basic unit of tracing. This is what 51 * is printed in the end as a single line in the trace output, such as: 52 * 53 * bash-15816 [01] 235.197585: idle_cpu <- irq_enter 54 */ 55 struct trace_entry { 56 unsigned short type; 57 unsigned char flags; 58 unsigned char preempt_count; 59 int pid; 60 }; 61 62 #define TRACE_EVENT_TYPE_MAX \ 63 ((1 << (sizeof(((struct trace_entry *)0)->type) * 8)) - 1) 64 65 /* 66 * Trace iterator - used by printout routines who present trace 67 * results to users and which routines might sleep, etc: 68 */ 69 struct trace_iterator { 70 struct trace_array *tr; 71 struct tracer *trace; 72 struct trace_buffer *trace_buffer; 73 void *private; 74 int cpu_file; 75 struct mutex mutex; 76 struct ring_buffer_iter **buffer_iter; 77 unsigned long iter_flags; 78 79 /* trace_seq for __print_flags() and __print_symbolic() etc. */ 80 struct trace_seq tmp_seq; 81 82 cpumask_var_t started; 83 84 /* it's true when current open file is snapshot */ 85 bool snapshot; 86 87 /* The below is zeroed out in pipe_read */ 88 struct trace_seq seq; 89 struct trace_entry *ent; 90 unsigned long lost_events; 91 int leftover; 92 int ent_size; 93 int cpu; 94 u64 ts; 95 96 loff_t pos; 97 long idx; 98 99 /* All new field here will be zeroed out in pipe_read */ 100 }; 101 102 enum trace_iter_flags { 103 TRACE_FILE_LAT_FMT = 1, 104 TRACE_FILE_ANNOTATE = 2, 105 TRACE_FILE_TIME_IN_NS = 4, 106 }; 107 108 109 typedef enum print_line_t (*trace_print_func)(struct trace_iterator *iter, 110 int flags, struct trace_event *event); 111 112 struct trace_event_functions { 113 trace_print_func trace; 114 trace_print_func raw; 115 trace_print_func hex; 116 trace_print_func binary; 117 }; 118 119 struct trace_event { 120 struct hlist_node node; 121 struct list_head list; 122 int type; 123 struct trace_event_functions *funcs; 124 }; 125 126 extern int register_trace_event(struct trace_event *event); 127 extern int unregister_trace_event(struct trace_event *event); 128 129 /* Return values for print_line callback */ 130 enum print_line_t { 131 TRACE_TYPE_PARTIAL_LINE = 0, /* Retry after flushing the seq */ 132 TRACE_TYPE_HANDLED = 1, 133 TRACE_TYPE_UNHANDLED = 2, /* Relay to other output functions */ 134 TRACE_TYPE_NO_CONSUME = 3 /* Handled but ask to not consume */ 135 }; 136 137 /* 138 * Several functions return TRACE_TYPE_PARTIAL_LINE if the trace_seq 139 * overflowed, and TRACE_TYPE_HANDLED otherwise. This helper function 140 * simplifies those functions and keeps them in sync. 141 */ 142 static inline enum print_line_t trace_handle_return(struct trace_seq *s) 143 { 144 return trace_seq_has_overflowed(s) ? 145 TRACE_TYPE_PARTIAL_LINE : TRACE_TYPE_HANDLED; 146 } 147 148 void tracing_generic_entry_update(struct trace_entry *entry, 149 unsigned long flags, 150 int pc); 151 struct trace_event_file; 152 153 struct ring_buffer_event * 154 trace_event_buffer_lock_reserve(struct ring_buffer **current_buffer, 155 struct trace_event_file *trace_file, 156 int type, unsigned long len, 157 unsigned long flags, int pc); 158 159 void tracing_record_cmdline(struct task_struct *tsk); 160 161 int trace_output_call(struct trace_iterator *iter, char *name, char *fmt, ...); 162 163 struct event_filter; 164 165 enum trace_reg { 166 TRACE_REG_REGISTER, 167 TRACE_REG_UNREGISTER, 168 #ifdef CONFIG_PERF_EVENTS 169 TRACE_REG_PERF_REGISTER, 170 TRACE_REG_PERF_UNREGISTER, 171 TRACE_REG_PERF_OPEN, 172 TRACE_REG_PERF_CLOSE, 173 TRACE_REG_PERF_ADD, 174 TRACE_REG_PERF_DEL, 175 #endif 176 }; 177 178 struct trace_event_call; 179 180 struct trace_event_class { 181 const char *system; 182 void *probe; 183 #ifdef CONFIG_PERF_EVENTS 184 void *perf_probe; 185 #endif 186 int (*reg)(struct trace_event_call *event, 187 enum trace_reg type, void *data); 188 int (*define_fields)(struct trace_event_call *); 189 struct list_head *(*get_fields)(struct trace_event_call *); 190 struct list_head fields; 191 int (*raw_init)(struct trace_event_call *); 192 }; 193 194 extern int trace_event_reg(struct trace_event_call *event, 195 enum trace_reg type, void *data); 196 197 struct trace_event_buffer { 198 struct ring_buffer *buffer; 199 struct ring_buffer_event *event; 200 struct trace_event_file *trace_file; 201 void *entry; 202 unsigned long flags; 203 int pc; 204 }; 205 206 void *trace_event_buffer_reserve(struct trace_event_buffer *fbuffer, 207 struct trace_event_file *trace_file, 208 unsigned long len); 209 210 void trace_event_buffer_commit(struct trace_event_buffer *fbuffer); 211 212 enum { 213 TRACE_EVENT_FL_FILTERED_BIT, 214 TRACE_EVENT_FL_CAP_ANY_BIT, 215 TRACE_EVENT_FL_NO_SET_FILTER_BIT, 216 TRACE_EVENT_FL_IGNORE_ENABLE_BIT, 217 TRACE_EVENT_FL_WAS_ENABLED_BIT, 218 TRACE_EVENT_FL_TRACEPOINT_BIT, 219 TRACE_EVENT_FL_KPROBE_BIT, 220 TRACE_EVENT_FL_UPROBE_BIT, 221 }; 222 223 /* 224 * Event flags: 225 * FILTERED - The event has a filter attached 226 * CAP_ANY - Any user can enable for perf 227 * NO_SET_FILTER - Set when filter has error and is to be ignored 228 * IGNORE_ENABLE - For trace internal events, do not enable with debugfs file 229 * WAS_ENABLED - Set and stays set when an event was ever enabled 230 * (used for module unloading, if a module event is enabled, 231 * it is best to clear the buffers that used it). 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_WAS_ENABLED = (1 << TRACE_EVENT_FL_WAS_ENABLED_BIT), 242 TRACE_EVENT_FL_TRACEPOINT = (1 << TRACE_EVENT_FL_TRACEPOINT_BIT), 243 TRACE_EVENT_FL_KPROBE = (1 << TRACE_EVENT_FL_KPROBE_BIT), 244 TRACE_EVENT_FL_UPROBE = (1 << TRACE_EVENT_FL_UPROBE_BIT), 245 }; 246 247 #define TRACE_EVENT_FL_UKPROBE (TRACE_EVENT_FL_KPROBE | TRACE_EVENT_FL_UPROBE) 248 249 struct trace_event_call { 250 struct list_head list; 251 struct trace_event_class *class; 252 union { 253 char *name; 254 /* Set TRACE_EVENT_FL_TRACEPOINT flag when using "tp" */ 255 struct tracepoint *tp; 256 }; 257 struct trace_event event; 258 char *print_fmt; 259 struct event_filter *filter; 260 void *mod; 261 void *data; 262 /* 263 * bit 0: filter_active 264 * bit 1: allow trace by non root (cap any) 265 * bit 2: failed to apply filter 266 * bit 3: trace internal event (do not enable) 267 * bit 4: Event was enabled by module 268 * bit 5: use call filter rather than file filter 269 * bit 6: Event is a tracepoint 270 */ 271 int flags; /* static flags of different events */ 272 273 #ifdef CONFIG_PERF_EVENTS 274 int perf_refcount; 275 struct hlist_head __percpu *perf_events; 276 struct bpf_prog *prog; 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_FILTERED_BIT, 299 EVENT_FILE_FL_NO_SET_FILTER_BIT, 300 EVENT_FILE_FL_SOFT_MODE_BIT, 301 EVENT_FILE_FL_SOFT_DISABLED_BIT, 302 EVENT_FILE_FL_TRIGGER_MODE_BIT, 303 EVENT_FILE_FL_TRIGGER_COND_BIT, 304 EVENT_FILE_FL_PID_FILTER_BIT, 305 }; 306 307 /* 308 * Event file flags: 309 * ENABLED - The event is enabled 310 * RECORDED_CMD - The comms should be recorded at sched_switch 311 * FILTERED - The event has a filter attached 312 * NO_SET_FILTER - Set when filter has error and is to be ignored 313 * SOFT_MODE - The event is enabled/disabled by SOFT_DISABLED 314 * SOFT_DISABLED - When set, do not trace the event (even though its 315 * tracepoint may be enabled) 316 * TRIGGER_MODE - When set, invoke the triggers associated with the event 317 * TRIGGER_COND - When set, one or more triggers has an associated filter 318 * PID_FILTER - When set, the event is filtered based on pid 319 */ 320 enum { 321 EVENT_FILE_FL_ENABLED = (1 << EVENT_FILE_FL_ENABLED_BIT), 322 EVENT_FILE_FL_RECORDED_CMD = (1 << EVENT_FILE_FL_RECORDED_CMD_BIT), 323 EVENT_FILE_FL_FILTERED = (1 << EVENT_FILE_FL_FILTERED_BIT), 324 EVENT_FILE_FL_NO_SET_FILTER = (1 << EVENT_FILE_FL_NO_SET_FILTER_BIT), 325 EVENT_FILE_FL_SOFT_MODE = (1 << EVENT_FILE_FL_SOFT_MODE_BIT), 326 EVENT_FILE_FL_SOFT_DISABLED = (1 << EVENT_FILE_FL_SOFT_DISABLED_BIT), 327 EVENT_FILE_FL_TRIGGER_MODE = (1 << EVENT_FILE_FL_TRIGGER_MODE_BIT), 328 EVENT_FILE_FL_TRIGGER_COND = (1 << EVENT_FILE_FL_TRIGGER_COND_BIT), 329 EVENT_FILE_FL_PID_FILTER = (1 << EVENT_FILE_FL_PID_FILTER_BIT), 330 }; 331 332 struct trace_event_file { 333 struct list_head list; 334 struct trace_event_call *event_call; 335 struct event_filter *filter; 336 struct dentry *dir; 337 struct trace_array *tr; 338 struct trace_subsystem_dir *system; 339 struct list_head triggers; 340 341 /* 342 * 32 bit flags: 343 * bit 0: enabled 344 * bit 1: enabled cmd record 345 * bit 2: enable/disable with the soft disable bit 346 * bit 3: soft disabled 347 * bit 4: trigger enabled 348 * 349 * Note: The bits must be set atomically to prevent races 350 * from other writers. Reads of flags do not need to be in 351 * sync as they occur in critical sections. But the way flags 352 * is currently used, these changes do not affect the code 353 * except that when a change is made, it may have a slight 354 * delay in propagating the changes to other CPUs due to 355 * caching and such. Which is mostly OK ;-) 356 */ 357 unsigned long flags; 358 atomic_t sm_ref; /* soft-mode reference counter */ 359 atomic_t tm_ref; /* trigger-mode reference counter */ 360 }; 361 362 #define __TRACE_EVENT_FLAGS(name, value) \ 363 static int __init trace_init_flags_##name(void) \ 364 { \ 365 event_##name.flags |= value; \ 366 return 0; \ 367 } \ 368 early_initcall(trace_init_flags_##name); 369 370 #define __TRACE_EVENT_PERF_PERM(name, expr...) \ 371 static int perf_perm_##name(struct trace_event_call *tp_event, \ 372 struct perf_event *p_event) \ 373 { \ 374 return ({ expr; }); \ 375 } \ 376 static int __init trace_init_perf_perm_##name(void) \ 377 { \ 378 event_##name.perf_perm = &perf_perm_##name; \ 379 return 0; \ 380 } \ 381 early_initcall(trace_init_perf_perm_##name); 382 383 #define PERF_MAX_TRACE_SIZE 2048 384 385 #define MAX_FILTER_STR_VAL 256 /* Should handle KSYM_SYMBOL_LEN */ 386 387 enum event_trigger_type { 388 ETT_NONE = (0), 389 ETT_TRACE_ONOFF = (1 << 0), 390 ETT_SNAPSHOT = (1 << 1), 391 ETT_STACKTRACE = (1 << 2), 392 ETT_EVENT_ENABLE = (1 << 3), 393 ETT_EVENT_HIST = (1 << 4), 394 ETT_HIST_ENABLE = (1 << 5), 395 }; 396 397 extern int filter_match_preds(struct event_filter *filter, void *rec); 398 399 extern enum event_trigger_type event_triggers_call(struct trace_event_file *file, 400 void *rec); 401 extern void event_triggers_post_call(struct trace_event_file *file, 402 enum event_trigger_type tt, 403 void *rec); 404 405 bool trace_event_ignore_this_pid(struct trace_event_file *trace_file); 406 407 /** 408 * trace_trigger_soft_disabled - do triggers and test if soft disabled 409 * @file: The file pointer of the event to test 410 * 411 * If any triggers without filters are attached to this event, they 412 * will be called here. If the event is soft disabled and has no 413 * triggers that require testing the fields, it will return true, 414 * otherwise false. 415 */ 416 static inline bool 417 trace_trigger_soft_disabled(struct trace_event_file *file) 418 { 419 unsigned long eflags = file->flags; 420 421 if (!(eflags & EVENT_FILE_FL_TRIGGER_COND)) { 422 if (eflags & EVENT_FILE_FL_TRIGGER_MODE) 423 event_triggers_call(file, NULL); 424 if (eflags & EVENT_FILE_FL_SOFT_DISABLED) 425 return true; 426 if (eflags & EVENT_FILE_FL_PID_FILTER) 427 return trace_event_ignore_this_pid(file); 428 } 429 return false; 430 } 431 432 #ifdef CONFIG_BPF_EVENTS 433 unsigned int trace_call_bpf(struct bpf_prog *prog, void *ctx); 434 #else 435 static inline unsigned int trace_call_bpf(struct bpf_prog *prog, void *ctx) 436 { 437 return 1; 438 } 439 #endif 440 441 enum { 442 FILTER_OTHER = 0, 443 FILTER_STATIC_STRING, 444 FILTER_DYN_STRING, 445 FILTER_PTR_STRING, 446 FILTER_TRACE_FN, 447 FILTER_COMM, 448 FILTER_CPU, 449 }; 450 451 extern int trace_event_raw_init(struct trace_event_call *call); 452 extern int trace_define_field(struct trace_event_call *call, const char *type, 453 const char *name, int offset, int size, 454 int is_signed, int filter_type); 455 extern int trace_add_event_call(struct trace_event_call *call); 456 extern int trace_remove_event_call(struct trace_event_call *call); 457 extern int trace_event_get_offsets(struct trace_event_call *call); 458 459 #define is_signed_type(type) (((type)(-1)) < (type)1) 460 461 int trace_set_clr_event(const char *system, const char *event, int set); 462 463 /* 464 * The double __builtin_constant_p is because gcc will give us an error 465 * if we try to allocate the static variable to fmt if it is not a 466 * constant. Even with the outer if statement optimizing out. 467 */ 468 #define event_trace_printk(ip, fmt, args...) \ 469 do { \ 470 __trace_printk_check_format(fmt, ##args); \ 471 tracing_record_cmdline(current); \ 472 if (__builtin_constant_p(fmt)) { \ 473 static const char *trace_printk_fmt \ 474 __attribute__((section("__trace_printk_fmt"))) = \ 475 __builtin_constant_p(fmt) ? fmt : NULL; \ 476 \ 477 __trace_bprintk(ip, trace_printk_fmt, ##args); \ 478 } else \ 479 __trace_printk(ip, fmt, ##args); \ 480 } while (0) 481 482 #ifdef CONFIG_PERF_EVENTS 483 struct perf_event; 484 485 DECLARE_PER_CPU(struct pt_regs, perf_trace_regs); 486 487 extern int perf_trace_init(struct perf_event *event); 488 extern void perf_trace_destroy(struct perf_event *event); 489 extern int perf_trace_add(struct perf_event *event, int flags); 490 extern void perf_trace_del(struct perf_event *event, int flags); 491 extern int ftrace_profile_set_filter(struct perf_event *event, int event_id, 492 char *filter_str); 493 extern void ftrace_profile_free_filter(struct perf_event *event); 494 void perf_trace_buf_update(void *record, u16 type); 495 void *perf_trace_buf_alloc(int size, struct pt_regs **regs, int *rctxp); 496 497 void perf_trace_run_bpf_submit(void *raw_data, int size, int rctx, 498 struct trace_event_call *call, u64 count, 499 struct pt_regs *regs, struct hlist_head *head, 500 struct task_struct *task); 501 502 static inline void 503 perf_trace_buf_submit(void *raw_data, int size, int rctx, u16 type, 504 u64 count, struct pt_regs *regs, void *head, 505 struct task_struct *task) 506 { 507 perf_tp_event(type, count, raw_data, size, regs, head, rctx, task); 508 } 509 #endif 510 511 #endif /* _LINUX_TRACE_EVENT_H */ 512