1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * trace_events_hist - trace event hist triggers 4 * 5 * Copyright (C) 2015 Tom Zanussi <tom.zanussi@linux.intel.com> 6 */ 7 8 #include <linux/module.h> 9 #include <linux/kallsyms.h> 10 #include <linux/security.h> 11 #include <linux/mutex.h> 12 #include <linux/slab.h> 13 #include <linux/stacktrace.h> 14 #include <linux/rculist.h> 15 #include <linux/tracefs.h> 16 17 /* for gfp flag names */ 18 #include <linux/trace_events.h> 19 #include <trace/events/mmflags.h> 20 21 #include "tracing_map.h" 22 #include "trace_synth.h" 23 24 #define ERRORS \ 25 C(NONE, "No error"), \ 26 C(DUPLICATE_VAR, "Variable already defined"), \ 27 C(VAR_NOT_UNIQUE, "Variable name not unique, need to use fully qualified name (subsys.event.var) for variable"), \ 28 C(TOO_MANY_VARS, "Too many variables defined"), \ 29 C(MALFORMED_ASSIGNMENT, "Malformed assignment"), \ 30 C(NAMED_MISMATCH, "Named hist trigger doesn't match existing named trigger (includes variables)"), \ 31 C(TRIGGER_EEXIST, "Hist trigger already exists"), \ 32 C(TRIGGER_ENOENT_CLEAR, "Can't clear or continue a nonexistent hist trigger"), \ 33 C(SET_CLOCK_FAIL, "Couldn't set trace_clock"), \ 34 C(BAD_FIELD_MODIFIER, "Invalid field modifier"), \ 35 C(TOO_MANY_SUBEXPR, "Too many subexpressions (3 max)"), \ 36 C(TIMESTAMP_MISMATCH, "Timestamp units in expression don't match"), \ 37 C(TOO_MANY_FIELD_VARS, "Too many field variables defined"), \ 38 C(EVENT_FILE_NOT_FOUND, "Event file not found"), \ 39 C(HIST_NOT_FOUND, "Matching event histogram not found"), \ 40 C(HIST_CREATE_FAIL, "Couldn't create histogram for field"), \ 41 C(SYNTH_VAR_NOT_FOUND, "Couldn't find synthetic variable"), \ 42 C(SYNTH_EVENT_NOT_FOUND,"Couldn't find synthetic event"), \ 43 C(SYNTH_TYPE_MISMATCH, "Param type doesn't match synthetic event field type"), \ 44 C(SYNTH_COUNT_MISMATCH, "Param count doesn't match synthetic event field count"), \ 45 C(FIELD_VAR_PARSE_FAIL, "Couldn't parse field variable"), \ 46 C(VAR_CREATE_FIND_FAIL, "Couldn't create or find variable"), \ 47 C(ONX_NOT_VAR, "For onmax(x) or onchange(x), x must be a variable"), \ 48 C(ONX_VAR_NOT_FOUND, "Couldn't find onmax or onchange variable"), \ 49 C(ONX_VAR_CREATE_FAIL, "Couldn't create onmax or onchange variable"), \ 50 C(FIELD_VAR_CREATE_FAIL,"Couldn't create field variable"), \ 51 C(TOO_MANY_PARAMS, "Too many action params"), \ 52 C(PARAM_NOT_FOUND, "Couldn't find param"), \ 53 C(INVALID_PARAM, "Invalid action param"), \ 54 C(ACTION_NOT_FOUND, "No action found"), \ 55 C(NO_SAVE_PARAMS, "No params found for save()"), \ 56 C(TOO_MANY_SAVE_ACTIONS,"Can't have more than one save() action per hist"), \ 57 C(ACTION_MISMATCH, "Handler doesn't support action"), \ 58 C(NO_CLOSING_PAREN, "No closing paren found"), \ 59 C(SUBSYS_NOT_FOUND, "Missing subsystem"), \ 60 C(INVALID_SUBSYS_EVENT, "Invalid subsystem or event name"), \ 61 C(INVALID_REF_KEY, "Using variable references in keys not supported"), \ 62 C(VAR_NOT_FOUND, "Couldn't find variable"), \ 63 C(FIELD_NOT_FOUND, "Couldn't find field"), \ 64 C(EMPTY_ASSIGNMENT, "Empty assignment"), \ 65 C(INVALID_SORT_MODIFIER,"Invalid sort modifier"), \ 66 C(EMPTY_SORT_FIELD, "Empty sort field"), \ 67 C(TOO_MANY_SORT_FIELDS, "Too many sort fields (Max = 2)"), \ 68 C(INVALID_SORT_FIELD, "Sort field must be a key or a val"), \ 69 C(INVALID_STR_OPERAND, "String type can not be an operand in expression"), 70 71 #undef C 72 #define C(a, b) HIST_ERR_##a 73 74 enum { ERRORS }; 75 76 #undef C 77 #define C(a, b) b 78 79 static const char *err_text[] = { ERRORS }; 80 81 struct hist_field; 82 83 typedef u64 (*hist_field_fn_t) (struct hist_field *field, 84 struct tracing_map_elt *elt, 85 struct trace_buffer *buffer, 86 struct ring_buffer_event *rbe, 87 void *event); 88 89 #define HIST_FIELD_OPERANDS_MAX 2 90 #define HIST_FIELDS_MAX (TRACING_MAP_FIELDS_MAX + TRACING_MAP_VARS_MAX) 91 #define HIST_ACTIONS_MAX 8 92 93 enum field_op_id { 94 FIELD_OP_NONE, 95 FIELD_OP_PLUS, 96 FIELD_OP_MINUS, 97 FIELD_OP_UNARY_MINUS, 98 }; 99 100 /* 101 * A hist_var (histogram variable) contains variable information for 102 * hist_fields having the HIST_FIELD_FL_VAR or HIST_FIELD_FL_VAR_REF 103 * flag set. A hist_var has a variable name e.g. ts0, and is 104 * associated with a given histogram trigger, as specified by 105 * hist_data. The hist_var idx is the unique index assigned to the 106 * variable by the hist trigger's tracing_map. The idx is what is 107 * used to set a variable's value and, by a variable reference, to 108 * retrieve it. 109 */ 110 struct hist_var { 111 char *name; 112 struct hist_trigger_data *hist_data; 113 unsigned int idx; 114 }; 115 116 struct hist_field { 117 struct ftrace_event_field *field; 118 unsigned long flags; 119 hist_field_fn_t fn; 120 unsigned int ref; 121 unsigned int size; 122 unsigned int offset; 123 unsigned int is_signed; 124 const char *type; 125 struct hist_field *operands[HIST_FIELD_OPERANDS_MAX]; 126 struct hist_trigger_data *hist_data; 127 128 /* 129 * Variable fields contain variable-specific info in var. 130 */ 131 struct hist_var var; 132 enum field_op_id operator; 133 char *system; 134 char *event_name; 135 136 /* 137 * The name field is used for EXPR and VAR_REF fields. VAR 138 * fields contain the variable name in var.name. 139 */ 140 char *name; 141 142 /* 143 * When a histogram trigger is hit, if it has any references 144 * to variables, the values of those variables are collected 145 * into a var_ref_vals array by resolve_var_refs(). The 146 * current value of each variable is read from the tracing_map 147 * using the hist field's hist_var.idx and entered into the 148 * var_ref_idx entry i.e. var_ref_vals[var_ref_idx]. 149 */ 150 unsigned int var_ref_idx; 151 bool read_once; 152 153 unsigned int var_str_idx; 154 }; 155 156 static u64 hist_field_none(struct hist_field *field, 157 struct tracing_map_elt *elt, 158 struct trace_buffer *buffer, 159 struct ring_buffer_event *rbe, 160 void *event) 161 { 162 return 0; 163 } 164 165 static u64 hist_field_counter(struct hist_field *field, 166 struct tracing_map_elt *elt, 167 struct trace_buffer *buffer, 168 struct ring_buffer_event *rbe, 169 void *event) 170 { 171 return 1; 172 } 173 174 static u64 hist_field_string(struct hist_field *hist_field, 175 struct tracing_map_elt *elt, 176 struct trace_buffer *buffer, 177 struct ring_buffer_event *rbe, 178 void *event) 179 { 180 char *addr = (char *)(event + hist_field->field->offset); 181 182 return (u64)(unsigned long)addr; 183 } 184 185 static u64 hist_field_dynstring(struct hist_field *hist_field, 186 struct tracing_map_elt *elt, 187 struct trace_buffer *buffer, 188 struct ring_buffer_event *rbe, 189 void *event) 190 { 191 u32 str_item = *(u32 *)(event + hist_field->field->offset); 192 int str_loc = str_item & 0xffff; 193 char *addr = (char *)(event + str_loc); 194 195 return (u64)(unsigned long)addr; 196 } 197 198 static u64 hist_field_pstring(struct hist_field *hist_field, 199 struct tracing_map_elt *elt, 200 struct trace_buffer *buffer, 201 struct ring_buffer_event *rbe, 202 void *event) 203 { 204 char **addr = (char **)(event + hist_field->field->offset); 205 206 return (u64)(unsigned long)*addr; 207 } 208 209 static u64 hist_field_log2(struct hist_field *hist_field, 210 struct tracing_map_elt *elt, 211 struct trace_buffer *buffer, 212 struct ring_buffer_event *rbe, 213 void *event) 214 { 215 struct hist_field *operand = hist_field->operands[0]; 216 217 u64 val = operand->fn(operand, elt, buffer, rbe, event); 218 219 return (u64) ilog2(roundup_pow_of_two(val)); 220 } 221 222 static u64 hist_field_plus(struct hist_field *hist_field, 223 struct tracing_map_elt *elt, 224 struct trace_buffer *buffer, 225 struct ring_buffer_event *rbe, 226 void *event) 227 { 228 struct hist_field *operand1 = hist_field->operands[0]; 229 struct hist_field *operand2 = hist_field->operands[1]; 230 231 u64 val1 = operand1->fn(operand1, elt, buffer, rbe, event); 232 u64 val2 = operand2->fn(operand2, elt, buffer, rbe, event); 233 234 return val1 + val2; 235 } 236 237 static u64 hist_field_minus(struct hist_field *hist_field, 238 struct tracing_map_elt *elt, 239 struct trace_buffer *buffer, 240 struct ring_buffer_event *rbe, 241 void *event) 242 { 243 struct hist_field *operand1 = hist_field->operands[0]; 244 struct hist_field *operand2 = hist_field->operands[1]; 245 246 u64 val1 = operand1->fn(operand1, elt, buffer, rbe, event); 247 u64 val2 = operand2->fn(operand2, elt, buffer, rbe, event); 248 249 return val1 - val2; 250 } 251 252 static u64 hist_field_unary_minus(struct hist_field *hist_field, 253 struct tracing_map_elt *elt, 254 struct trace_buffer *buffer, 255 struct ring_buffer_event *rbe, 256 void *event) 257 { 258 struct hist_field *operand = hist_field->operands[0]; 259 260 s64 sval = (s64)operand->fn(operand, elt, buffer, rbe, event); 261 u64 val = (u64)-sval; 262 263 return val; 264 } 265 266 #define DEFINE_HIST_FIELD_FN(type) \ 267 static u64 hist_field_##type(struct hist_field *hist_field, \ 268 struct tracing_map_elt *elt, \ 269 struct trace_buffer *buffer, \ 270 struct ring_buffer_event *rbe, \ 271 void *event) \ 272 { \ 273 type *addr = (type *)(event + hist_field->field->offset); \ 274 \ 275 return (u64)(unsigned long)*addr; \ 276 } 277 278 DEFINE_HIST_FIELD_FN(s64); 279 DEFINE_HIST_FIELD_FN(u64); 280 DEFINE_HIST_FIELD_FN(s32); 281 DEFINE_HIST_FIELD_FN(u32); 282 DEFINE_HIST_FIELD_FN(s16); 283 DEFINE_HIST_FIELD_FN(u16); 284 DEFINE_HIST_FIELD_FN(s8); 285 DEFINE_HIST_FIELD_FN(u8); 286 287 #define for_each_hist_field(i, hist_data) \ 288 for ((i) = 0; (i) < (hist_data)->n_fields; (i)++) 289 290 #define for_each_hist_val_field(i, hist_data) \ 291 for ((i) = 0; (i) < (hist_data)->n_vals; (i)++) 292 293 #define for_each_hist_key_field(i, hist_data) \ 294 for ((i) = (hist_data)->n_vals; (i) < (hist_data)->n_fields; (i)++) 295 296 #define HIST_STACKTRACE_DEPTH 16 297 #define HIST_STACKTRACE_SIZE (HIST_STACKTRACE_DEPTH * sizeof(unsigned long)) 298 #define HIST_STACKTRACE_SKIP 5 299 300 #define HITCOUNT_IDX 0 301 #define HIST_KEY_SIZE_MAX (MAX_FILTER_STR_VAL + HIST_STACKTRACE_SIZE) 302 303 enum hist_field_flags { 304 HIST_FIELD_FL_HITCOUNT = 1 << 0, 305 HIST_FIELD_FL_KEY = 1 << 1, 306 HIST_FIELD_FL_STRING = 1 << 2, 307 HIST_FIELD_FL_HEX = 1 << 3, 308 HIST_FIELD_FL_SYM = 1 << 4, 309 HIST_FIELD_FL_SYM_OFFSET = 1 << 5, 310 HIST_FIELD_FL_EXECNAME = 1 << 6, 311 HIST_FIELD_FL_SYSCALL = 1 << 7, 312 HIST_FIELD_FL_STACKTRACE = 1 << 8, 313 HIST_FIELD_FL_LOG2 = 1 << 9, 314 HIST_FIELD_FL_TIMESTAMP = 1 << 10, 315 HIST_FIELD_FL_TIMESTAMP_USECS = 1 << 11, 316 HIST_FIELD_FL_VAR = 1 << 12, 317 HIST_FIELD_FL_EXPR = 1 << 13, 318 HIST_FIELD_FL_VAR_REF = 1 << 14, 319 HIST_FIELD_FL_CPU = 1 << 15, 320 HIST_FIELD_FL_ALIAS = 1 << 16, 321 }; 322 323 struct var_defs { 324 unsigned int n_vars; 325 char *name[TRACING_MAP_VARS_MAX]; 326 char *expr[TRACING_MAP_VARS_MAX]; 327 }; 328 329 struct hist_trigger_attrs { 330 char *keys_str; 331 char *vals_str; 332 char *sort_key_str; 333 char *name; 334 char *clock; 335 bool pause; 336 bool cont; 337 bool clear; 338 bool ts_in_usecs; 339 unsigned int map_bits; 340 341 char *assignment_str[TRACING_MAP_VARS_MAX]; 342 unsigned int n_assignments; 343 344 char *action_str[HIST_ACTIONS_MAX]; 345 unsigned int n_actions; 346 347 struct var_defs var_defs; 348 }; 349 350 struct field_var { 351 struct hist_field *var; 352 struct hist_field *val; 353 }; 354 355 struct field_var_hist { 356 struct hist_trigger_data *hist_data; 357 char *cmd; 358 }; 359 360 struct hist_trigger_data { 361 struct hist_field *fields[HIST_FIELDS_MAX]; 362 unsigned int n_vals; 363 unsigned int n_keys; 364 unsigned int n_fields; 365 unsigned int n_vars; 366 unsigned int n_var_str; 367 unsigned int key_size; 368 struct tracing_map_sort_key sort_keys[TRACING_MAP_SORT_KEYS_MAX]; 369 unsigned int n_sort_keys; 370 struct trace_event_file *event_file; 371 struct hist_trigger_attrs *attrs; 372 struct tracing_map *map; 373 bool enable_timestamps; 374 bool remove; 375 struct hist_field *var_refs[TRACING_MAP_VARS_MAX]; 376 unsigned int n_var_refs; 377 378 struct action_data *actions[HIST_ACTIONS_MAX]; 379 unsigned int n_actions; 380 381 struct field_var *field_vars[SYNTH_FIELDS_MAX]; 382 unsigned int n_field_vars; 383 unsigned int n_field_var_str; 384 struct field_var_hist *field_var_hists[SYNTH_FIELDS_MAX]; 385 unsigned int n_field_var_hists; 386 387 struct field_var *save_vars[SYNTH_FIELDS_MAX]; 388 unsigned int n_save_vars; 389 unsigned int n_save_var_str; 390 }; 391 392 struct action_data; 393 394 typedef void (*action_fn_t) (struct hist_trigger_data *hist_data, 395 struct tracing_map_elt *elt, 396 struct trace_buffer *buffer, void *rec, 397 struct ring_buffer_event *rbe, void *key, 398 struct action_data *data, u64 *var_ref_vals); 399 400 typedef bool (*check_track_val_fn_t) (u64 track_val, u64 var_val); 401 402 enum handler_id { 403 HANDLER_ONMATCH = 1, 404 HANDLER_ONMAX, 405 HANDLER_ONCHANGE, 406 }; 407 408 enum action_id { 409 ACTION_SAVE = 1, 410 ACTION_TRACE, 411 ACTION_SNAPSHOT, 412 }; 413 414 struct action_data { 415 enum handler_id handler; 416 enum action_id action; 417 char *action_name; 418 action_fn_t fn; 419 420 unsigned int n_params; 421 char *params[SYNTH_FIELDS_MAX]; 422 423 /* 424 * When a histogram trigger is hit, the values of any 425 * references to variables, including variables being passed 426 * as parameters to synthetic events, are collected into a 427 * var_ref_vals array. This var_ref_idx array is an array of 428 * indices into the var_ref_vals array, one for each synthetic 429 * event param, and is passed to the synthetic event 430 * invocation. 431 */ 432 unsigned int var_ref_idx[TRACING_MAP_VARS_MAX]; 433 struct synth_event *synth_event; 434 bool use_trace_keyword; 435 char *synth_event_name; 436 437 union { 438 struct { 439 char *event; 440 char *event_system; 441 } match_data; 442 443 struct { 444 /* 445 * var_str contains the $-unstripped variable 446 * name referenced by var_ref, and used when 447 * printing the action. Because var_ref 448 * creation is deferred to create_actions(), 449 * we need a per-action way to save it until 450 * then, thus var_str. 451 */ 452 char *var_str; 453 454 /* 455 * var_ref refers to the variable being 456 * tracked e.g onmax($var). 457 */ 458 struct hist_field *var_ref; 459 460 /* 461 * track_var contains the 'invisible' tracking 462 * variable created to keep the current 463 * e.g. max value. 464 */ 465 struct hist_field *track_var; 466 467 check_track_val_fn_t check_val; 468 action_fn_t save_data; 469 } track_data; 470 }; 471 }; 472 473 struct track_data { 474 u64 track_val; 475 bool updated; 476 477 unsigned int key_len; 478 void *key; 479 struct tracing_map_elt elt; 480 481 struct action_data *action_data; 482 struct hist_trigger_data *hist_data; 483 }; 484 485 struct hist_elt_data { 486 char *comm; 487 u64 *var_ref_vals; 488 char *field_var_str[SYNTH_FIELDS_MAX]; 489 }; 490 491 struct snapshot_context { 492 struct tracing_map_elt *elt; 493 void *key; 494 }; 495 496 static void track_data_free(struct track_data *track_data) 497 { 498 struct hist_elt_data *elt_data; 499 500 if (!track_data) 501 return; 502 503 kfree(track_data->key); 504 505 elt_data = track_data->elt.private_data; 506 if (elt_data) { 507 kfree(elt_data->comm); 508 kfree(elt_data); 509 } 510 511 kfree(track_data); 512 } 513 514 static struct track_data *track_data_alloc(unsigned int key_len, 515 struct action_data *action_data, 516 struct hist_trigger_data *hist_data) 517 { 518 struct track_data *data = kzalloc(sizeof(*data), GFP_KERNEL); 519 struct hist_elt_data *elt_data; 520 521 if (!data) 522 return ERR_PTR(-ENOMEM); 523 524 data->key = kzalloc(key_len, GFP_KERNEL); 525 if (!data->key) { 526 track_data_free(data); 527 return ERR_PTR(-ENOMEM); 528 } 529 530 data->key_len = key_len; 531 data->action_data = action_data; 532 data->hist_data = hist_data; 533 534 elt_data = kzalloc(sizeof(*elt_data), GFP_KERNEL); 535 if (!elt_data) { 536 track_data_free(data); 537 return ERR_PTR(-ENOMEM); 538 } 539 540 data->elt.private_data = elt_data; 541 542 elt_data->comm = kzalloc(TASK_COMM_LEN, GFP_KERNEL); 543 if (!elt_data->comm) { 544 track_data_free(data); 545 return ERR_PTR(-ENOMEM); 546 } 547 548 return data; 549 } 550 551 static char last_cmd[MAX_FILTER_STR_VAL]; 552 static char last_cmd_loc[MAX_FILTER_STR_VAL]; 553 554 static int errpos(char *str) 555 { 556 return err_pos(last_cmd, str); 557 } 558 559 static void last_cmd_set(struct trace_event_file *file, char *str) 560 { 561 const char *system = NULL, *name = NULL; 562 struct trace_event_call *call; 563 564 if (!str) 565 return; 566 567 strcpy(last_cmd, "hist:"); 568 strncat(last_cmd, str, MAX_FILTER_STR_VAL - 1 - sizeof("hist:")); 569 570 if (file) { 571 call = file->event_call; 572 system = call->class->system; 573 if (system) { 574 name = trace_event_name(call); 575 if (!name) 576 system = NULL; 577 } 578 } 579 580 if (system) 581 snprintf(last_cmd_loc, MAX_FILTER_STR_VAL, "hist:%s:%s", system, name); 582 } 583 584 static void hist_err(struct trace_array *tr, u8 err_type, u8 err_pos) 585 { 586 tracing_log_err(tr, last_cmd_loc, last_cmd, err_text, 587 err_type, err_pos); 588 } 589 590 static void hist_err_clear(void) 591 { 592 last_cmd[0] = '\0'; 593 last_cmd_loc[0] = '\0'; 594 } 595 596 typedef void (*synth_probe_func_t) (void *__data, u64 *var_ref_vals, 597 unsigned int *var_ref_idx); 598 599 static inline void trace_synth(struct synth_event *event, u64 *var_ref_vals, 600 unsigned int *var_ref_idx) 601 { 602 struct tracepoint *tp = event->tp; 603 604 if (unlikely(atomic_read(&tp->key.enabled) > 0)) { 605 struct tracepoint_func *probe_func_ptr; 606 synth_probe_func_t probe_func; 607 void *__data; 608 609 if (!(cpu_online(raw_smp_processor_id()))) 610 return; 611 612 probe_func_ptr = rcu_dereference_sched((tp)->funcs); 613 if (probe_func_ptr) { 614 do { 615 probe_func = probe_func_ptr->func; 616 __data = probe_func_ptr->data; 617 probe_func(__data, var_ref_vals, var_ref_idx); 618 } while ((++probe_func_ptr)->func); 619 } 620 } 621 } 622 623 static void action_trace(struct hist_trigger_data *hist_data, 624 struct tracing_map_elt *elt, 625 struct trace_buffer *buffer, void *rec, 626 struct ring_buffer_event *rbe, void *key, 627 struct action_data *data, u64 *var_ref_vals) 628 { 629 struct synth_event *event = data->synth_event; 630 631 trace_synth(event, var_ref_vals, data->var_ref_idx); 632 } 633 634 struct hist_var_data { 635 struct list_head list; 636 struct hist_trigger_data *hist_data; 637 }; 638 639 static u64 hist_field_timestamp(struct hist_field *hist_field, 640 struct tracing_map_elt *elt, 641 struct trace_buffer *buffer, 642 struct ring_buffer_event *rbe, 643 void *event) 644 { 645 struct hist_trigger_data *hist_data = hist_field->hist_data; 646 struct trace_array *tr = hist_data->event_file->tr; 647 648 u64 ts = ring_buffer_event_time_stamp(buffer, rbe); 649 650 if (hist_data->attrs->ts_in_usecs && trace_clock_in_ns(tr)) 651 ts = ns2usecs(ts); 652 653 return ts; 654 } 655 656 static u64 hist_field_cpu(struct hist_field *hist_field, 657 struct tracing_map_elt *elt, 658 struct trace_buffer *buffer, 659 struct ring_buffer_event *rbe, 660 void *event) 661 { 662 int cpu = smp_processor_id(); 663 664 return cpu; 665 } 666 667 /** 668 * check_field_for_var_ref - Check if a VAR_REF field references a variable 669 * @hist_field: The VAR_REF field to check 670 * @var_data: The hist trigger that owns the variable 671 * @var_idx: The trigger variable identifier 672 * 673 * Check the given VAR_REF field to see whether or not it references 674 * the given variable associated with the given trigger. 675 * 676 * Return: The VAR_REF field if it does reference the variable, NULL if not 677 */ 678 static struct hist_field * 679 check_field_for_var_ref(struct hist_field *hist_field, 680 struct hist_trigger_data *var_data, 681 unsigned int var_idx) 682 { 683 WARN_ON(!(hist_field && hist_field->flags & HIST_FIELD_FL_VAR_REF)); 684 685 if (hist_field && hist_field->var.idx == var_idx && 686 hist_field->var.hist_data == var_data) 687 return hist_field; 688 689 return NULL; 690 } 691 692 /** 693 * find_var_ref - Check if a trigger has a reference to a trigger variable 694 * @hist_data: The hist trigger that might have a reference to the variable 695 * @var_data: The hist trigger that owns the variable 696 * @var_idx: The trigger variable identifier 697 * 698 * Check the list of var_refs[] on the first hist trigger to see 699 * whether any of them are references to the variable on the second 700 * trigger. 701 * 702 * Return: The VAR_REF field referencing the variable if so, NULL if not 703 */ 704 static struct hist_field *find_var_ref(struct hist_trigger_data *hist_data, 705 struct hist_trigger_data *var_data, 706 unsigned int var_idx) 707 { 708 struct hist_field *hist_field; 709 unsigned int i; 710 711 for (i = 0; i < hist_data->n_var_refs; i++) { 712 hist_field = hist_data->var_refs[i]; 713 if (check_field_for_var_ref(hist_field, var_data, var_idx)) 714 return hist_field; 715 } 716 717 return NULL; 718 } 719 720 /** 721 * find_any_var_ref - Check if there is a reference to a given trigger variable 722 * @hist_data: The hist trigger 723 * @var_idx: The trigger variable identifier 724 * 725 * Check to see whether the given variable is currently referenced by 726 * any other trigger. 727 * 728 * The trigger the variable is defined on is explicitly excluded - the 729 * assumption being that a self-reference doesn't prevent a trigger 730 * from being removed. 731 * 732 * Return: The VAR_REF field referencing the variable if so, NULL if not 733 */ 734 static struct hist_field *find_any_var_ref(struct hist_trigger_data *hist_data, 735 unsigned int var_idx) 736 { 737 struct trace_array *tr = hist_data->event_file->tr; 738 struct hist_field *found = NULL; 739 struct hist_var_data *var_data; 740 741 list_for_each_entry(var_data, &tr->hist_vars, list) { 742 if (var_data->hist_data == hist_data) 743 continue; 744 found = find_var_ref(var_data->hist_data, hist_data, var_idx); 745 if (found) 746 break; 747 } 748 749 return found; 750 } 751 752 /** 753 * check_var_refs - Check if there is a reference to any of trigger's variables 754 * @hist_data: The hist trigger 755 * 756 * A trigger can define one or more variables. If any one of them is 757 * currently referenced by any other trigger, this function will 758 * determine that. 759 760 * Typically used to determine whether or not a trigger can be removed 761 * - if there are any references to a trigger's variables, it cannot. 762 * 763 * Return: True if there is a reference to any of trigger's variables 764 */ 765 static bool check_var_refs(struct hist_trigger_data *hist_data) 766 { 767 struct hist_field *field; 768 bool found = false; 769 int i; 770 771 for_each_hist_field(i, hist_data) { 772 field = hist_data->fields[i]; 773 if (field && field->flags & HIST_FIELD_FL_VAR) { 774 if (find_any_var_ref(hist_data, field->var.idx)) { 775 found = true; 776 break; 777 } 778 } 779 } 780 781 return found; 782 } 783 784 static struct hist_var_data *find_hist_vars(struct hist_trigger_data *hist_data) 785 { 786 struct trace_array *tr = hist_data->event_file->tr; 787 struct hist_var_data *var_data, *found = NULL; 788 789 list_for_each_entry(var_data, &tr->hist_vars, list) { 790 if (var_data->hist_data == hist_data) { 791 found = var_data; 792 break; 793 } 794 } 795 796 return found; 797 } 798 799 static bool field_has_hist_vars(struct hist_field *hist_field, 800 unsigned int level) 801 { 802 int i; 803 804 if (level > 3) 805 return false; 806 807 if (!hist_field) 808 return false; 809 810 if (hist_field->flags & HIST_FIELD_FL_VAR || 811 hist_field->flags & HIST_FIELD_FL_VAR_REF) 812 return true; 813 814 for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++) { 815 struct hist_field *operand; 816 817 operand = hist_field->operands[i]; 818 if (field_has_hist_vars(operand, level + 1)) 819 return true; 820 } 821 822 return false; 823 } 824 825 static bool has_hist_vars(struct hist_trigger_data *hist_data) 826 { 827 struct hist_field *hist_field; 828 int i; 829 830 for_each_hist_field(i, hist_data) { 831 hist_field = hist_data->fields[i]; 832 if (field_has_hist_vars(hist_field, 0)) 833 return true; 834 } 835 836 return false; 837 } 838 839 static int save_hist_vars(struct hist_trigger_data *hist_data) 840 { 841 struct trace_array *tr = hist_data->event_file->tr; 842 struct hist_var_data *var_data; 843 844 var_data = find_hist_vars(hist_data); 845 if (var_data) 846 return 0; 847 848 if (tracing_check_open_get_tr(tr)) 849 return -ENODEV; 850 851 var_data = kzalloc(sizeof(*var_data), GFP_KERNEL); 852 if (!var_data) { 853 trace_array_put(tr); 854 return -ENOMEM; 855 } 856 857 var_data->hist_data = hist_data; 858 list_add(&var_data->list, &tr->hist_vars); 859 860 return 0; 861 } 862 863 static void remove_hist_vars(struct hist_trigger_data *hist_data) 864 { 865 struct trace_array *tr = hist_data->event_file->tr; 866 struct hist_var_data *var_data; 867 868 var_data = find_hist_vars(hist_data); 869 if (!var_data) 870 return; 871 872 if (WARN_ON(check_var_refs(hist_data))) 873 return; 874 875 list_del(&var_data->list); 876 877 kfree(var_data); 878 879 trace_array_put(tr); 880 } 881 882 static struct hist_field *find_var_field(struct hist_trigger_data *hist_data, 883 const char *var_name) 884 { 885 struct hist_field *hist_field, *found = NULL; 886 int i; 887 888 for_each_hist_field(i, hist_data) { 889 hist_field = hist_data->fields[i]; 890 if (hist_field && hist_field->flags & HIST_FIELD_FL_VAR && 891 strcmp(hist_field->var.name, var_name) == 0) { 892 found = hist_field; 893 break; 894 } 895 } 896 897 return found; 898 } 899 900 static struct hist_field *find_var(struct hist_trigger_data *hist_data, 901 struct trace_event_file *file, 902 const char *var_name) 903 { 904 struct hist_trigger_data *test_data; 905 struct event_trigger_data *test; 906 struct hist_field *hist_field; 907 908 lockdep_assert_held(&event_mutex); 909 910 hist_field = find_var_field(hist_data, var_name); 911 if (hist_field) 912 return hist_field; 913 914 list_for_each_entry(test, &file->triggers, list) { 915 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 916 test_data = test->private_data; 917 hist_field = find_var_field(test_data, var_name); 918 if (hist_field) 919 return hist_field; 920 } 921 } 922 923 return NULL; 924 } 925 926 static struct trace_event_file *find_var_file(struct trace_array *tr, 927 char *system, 928 char *event_name, 929 char *var_name) 930 { 931 struct hist_trigger_data *var_hist_data; 932 struct hist_var_data *var_data; 933 struct trace_event_file *file, *found = NULL; 934 935 if (system) 936 return find_event_file(tr, system, event_name); 937 938 list_for_each_entry(var_data, &tr->hist_vars, list) { 939 var_hist_data = var_data->hist_data; 940 file = var_hist_data->event_file; 941 if (file == found) 942 continue; 943 944 if (find_var_field(var_hist_data, var_name)) { 945 if (found) { 946 hist_err(tr, HIST_ERR_VAR_NOT_UNIQUE, errpos(var_name)); 947 return NULL; 948 } 949 950 found = file; 951 } 952 } 953 954 return found; 955 } 956 957 static struct hist_field *find_file_var(struct trace_event_file *file, 958 const char *var_name) 959 { 960 struct hist_trigger_data *test_data; 961 struct event_trigger_data *test; 962 struct hist_field *hist_field; 963 964 lockdep_assert_held(&event_mutex); 965 966 list_for_each_entry(test, &file->triggers, list) { 967 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 968 test_data = test->private_data; 969 hist_field = find_var_field(test_data, var_name); 970 if (hist_field) 971 return hist_field; 972 } 973 } 974 975 return NULL; 976 } 977 978 static struct hist_field * 979 find_match_var(struct hist_trigger_data *hist_data, char *var_name) 980 { 981 struct trace_array *tr = hist_data->event_file->tr; 982 struct hist_field *hist_field, *found = NULL; 983 struct trace_event_file *file; 984 unsigned int i; 985 986 for (i = 0; i < hist_data->n_actions; i++) { 987 struct action_data *data = hist_data->actions[i]; 988 989 if (data->handler == HANDLER_ONMATCH) { 990 char *system = data->match_data.event_system; 991 char *event_name = data->match_data.event; 992 993 file = find_var_file(tr, system, event_name, var_name); 994 if (!file) 995 continue; 996 hist_field = find_file_var(file, var_name); 997 if (hist_field) { 998 if (found) { 999 hist_err(tr, HIST_ERR_VAR_NOT_UNIQUE, 1000 errpos(var_name)); 1001 return ERR_PTR(-EINVAL); 1002 } 1003 1004 found = hist_field; 1005 } 1006 } 1007 } 1008 return found; 1009 } 1010 1011 static struct hist_field *find_event_var(struct hist_trigger_data *hist_data, 1012 char *system, 1013 char *event_name, 1014 char *var_name) 1015 { 1016 struct trace_array *tr = hist_data->event_file->tr; 1017 struct hist_field *hist_field = NULL; 1018 struct trace_event_file *file; 1019 1020 if (!system || !event_name) { 1021 hist_field = find_match_var(hist_data, var_name); 1022 if (IS_ERR(hist_field)) 1023 return NULL; 1024 if (hist_field) 1025 return hist_field; 1026 } 1027 1028 file = find_var_file(tr, system, event_name, var_name); 1029 if (!file) 1030 return NULL; 1031 1032 hist_field = find_file_var(file, var_name); 1033 1034 return hist_field; 1035 } 1036 1037 static u64 hist_field_var_ref(struct hist_field *hist_field, 1038 struct tracing_map_elt *elt, 1039 struct trace_buffer *buffer, 1040 struct ring_buffer_event *rbe, 1041 void *event) 1042 { 1043 struct hist_elt_data *elt_data; 1044 u64 var_val = 0; 1045 1046 if (WARN_ON_ONCE(!elt)) 1047 return var_val; 1048 1049 elt_data = elt->private_data; 1050 var_val = elt_data->var_ref_vals[hist_field->var_ref_idx]; 1051 1052 return var_val; 1053 } 1054 1055 static bool resolve_var_refs(struct hist_trigger_data *hist_data, void *key, 1056 u64 *var_ref_vals, bool self) 1057 { 1058 struct hist_trigger_data *var_data; 1059 struct tracing_map_elt *var_elt; 1060 struct hist_field *hist_field; 1061 unsigned int i, var_idx; 1062 bool resolved = true; 1063 u64 var_val = 0; 1064 1065 for (i = 0; i < hist_data->n_var_refs; i++) { 1066 hist_field = hist_data->var_refs[i]; 1067 var_idx = hist_field->var.idx; 1068 var_data = hist_field->var.hist_data; 1069 1070 if (var_data == NULL) { 1071 resolved = false; 1072 break; 1073 } 1074 1075 if ((self && var_data != hist_data) || 1076 (!self && var_data == hist_data)) 1077 continue; 1078 1079 var_elt = tracing_map_lookup(var_data->map, key); 1080 if (!var_elt) { 1081 resolved = false; 1082 break; 1083 } 1084 1085 if (!tracing_map_var_set(var_elt, var_idx)) { 1086 resolved = false; 1087 break; 1088 } 1089 1090 if (self || !hist_field->read_once) 1091 var_val = tracing_map_read_var(var_elt, var_idx); 1092 else 1093 var_val = tracing_map_read_var_once(var_elt, var_idx); 1094 1095 var_ref_vals[i] = var_val; 1096 } 1097 1098 return resolved; 1099 } 1100 1101 static const char *hist_field_name(struct hist_field *field, 1102 unsigned int level) 1103 { 1104 const char *field_name = ""; 1105 1106 if (level > 1) 1107 return field_name; 1108 1109 if (field->field) 1110 field_name = field->field->name; 1111 else if (field->flags & HIST_FIELD_FL_LOG2 || 1112 field->flags & HIST_FIELD_FL_ALIAS) 1113 field_name = hist_field_name(field->operands[0], ++level); 1114 else if (field->flags & HIST_FIELD_FL_CPU) 1115 field_name = "common_cpu"; 1116 else if (field->flags & HIST_FIELD_FL_EXPR || 1117 field->flags & HIST_FIELD_FL_VAR_REF) { 1118 if (field->system) { 1119 static char full_name[MAX_FILTER_STR_VAL]; 1120 1121 strcat(full_name, field->system); 1122 strcat(full_name, "."); 1123 strcat(full_name, field->event_name); 1124 strcat(full_name, "."); 1125 strcat(full_name, field->name); 1126 field_name = full_name; 1127 } else 1128 field_name = field->name; 1129 } else if (field->flags & HIST_FIELD_FL_TIMESTAMP) 1130 field_name = "common_timestamp"; 1131 1132 if (field_name == NULL) 1133 field_name = ""; 1134 1135 return field_name; 1136 } 1137 1138 static hist_field_fn_t select_value_fn(int field_size, int field_is_signed) 1139 { 1140 hist_field_fn_t fn = NULL; 1141 1142 switch (field_size) { 1143 case 8: 1144 if (field_is_signed) 1145 fn = hist_field_s64; 1146 else 1147 fn = hist_field_u64; 1148 break; 1149 case 4: 1150 if (field_is_signed) 1151 fn = hist_field_s32; 1152 else 1153 fn = hist_field_u32; 1154 break; 1155 case 2: 1156 if (field_is_signed) 1157 fn = hist_field_s16; 1158 else 1159 fn = hist_field_u16; 1160 break; 1161 case 1: 1162 if (field_is_signed) 1163 fn = hist_field_s8; 1164 else 1165 fn = hist_field_u8; 1166 break; 1167 } 1168 1169 return fn; 1170 } 1171 1172 static int parse_map_size(char *str) 1173 { 1174 unsigned long size, map_bits; 1175 int ret; 1176 1177 ret = kstrtoul(str, 0, &size); 1178 if (ret) 1179 goto out; 1180 1181 map_bits = ilog2(roundup_pow_of_two(size)); 1182 if (map_bits < TRACING_MAP_BITS_MIN || 1183 map_bits > TRACING_MAP_BITS_MAX) 1184 ret = -EINVAL; 1185 else 1186 ret = map_bits; 1187 out: 1188 return ret; 1189 } 1190 1191 static void destroy_hist_trigger_attrs(struct hist_trigger_attrs *attrs) 1192 { 1193 unsigned int i; 1194 1195 if (!attrs) 1196 return; 1197 1198 for (i = 0; i < attrs->n_assignments; i++) 1199 kfree(attrs->assignment_str[i]); 1200 1201 for (i = 0; i < attrs->n_actions; i++) 1202 kfree(attrs->action_str[i]); 1203 1204 kfree(attrs->name); 1205 kfree(attrs->sort_key_str); 1206 kfree(attrs->keys_str); 1207 kfree(attrs->vals_str); 1208 kfree(attrs->clock); 1209 kfree(attrs); 1210 } 1211 1212 static int parse_action(char *str, struct hist_trigger_attrs *attrs) 1213 { 1214 int ret = -EINVAL; 1215 1216 if (attrs->n_actions >= HIST_ACTIONS_MAX) 1217 return ret; 1218 1219 if ((str_has_prefix(str, "onmatch(")) || 1220 (str_has_prefix(str, "onmax(")) || 1221 (str_has_prefix(str, "onchange("))) { 1222 attrs->action_str[attrs->n_actions] = kstrdup(str, GFP_KERNEL); 1223 if (!attrs->action_str[attrs->n_actions]) { 1224 ret = -ENOMEM; 1225 return ret; 1226 } 1227 attrs->n_actions++; 1228 ret = 0; 1229 } 1230 return ret; 1231 } 1232 1233 static int parse_assignment(struct trace_array *tr, 1234 char *str, struct hist_trigger_attrs *attrs) 1235 { 1236 int len, ret = 0; 1237 1238 if ((len = str_has_prefix(str, "key=")) || 1239 (len = str_has_prefix(str, "keys="))) { 1240 attrs->keys_str = kstrdup(str + len, GFP_KERNEL); 1241 if (!attrs->keys_str) { 1242 ret = -ENOMEM; 1243 goto out; 1244 } 1245 } else if ((len = str_has_prefix(str, "val=")) || 1246 (len = str_has_prefix(str, "vals=")) || 1247 (len = str_has_prefix(str, "values="))) { 1248 attrs->vals_str = kstrdup(str + len, GFP_KERNEL); 1249 if (!attrs->vals_str) { 1250 ret = -ENOMEM; 1251 goto out; 1252 } 1253 } else if ((len = str_has_prefix(str, "sort="))) { 1254 attrs->sort_key_str = kstrdup(str + len, GFP_KERNEL); 1255 if (!attrs->sort_key_str) { 1256 ret = -ENOMEM; 1257 goto out; 1258 } 1259 } else if (str_has_prefix(str, "name=")) { 1260 attrs->name = kstrdup(str, GFP_KERNEL); 1261 if (!attrs->name) { 1262 ret = -ENOMEM; 1263 goto out; 1264 } 1265 } else if ((len = str_has_prefix(str, "clock="))) { 1266 str += len; 1267 1268 str = strstrip(str); 1269 attrs->clock = kstrdup(str, GFP_KERNEL); 1270 if (!attrs->clock) { 1271 ret = -ENOMEM; 1272 goto out; 1273 } 1274 } else if ((len = str_has_prefix(str, "size="))) { 1275 int map_bits = parse_map_size(str + len); 1276 1277 if (map_bits < 0) { 1278 ret = map_bits; 1279 goto out; 1280 } 1281 attrs->map_bits = map_bits; 1282 } else { 1283 char *assignment; 1284 1285 if (attrs->n_assignments == TRACING_MAP_VARS_MAX) { 1286 hist_err(tr, HIST_ERR_TOO_MANY_VARS, errpos(str)); 1287 ret = -EINVAL; 1288 goto out; 1289 } 1290 1291 assignment = kstrdup(str, GFP_KERNEL); 1292 if (!assignment) { 1293 ret = -ENOMEM; 1294 goto out; 1295 } 1296 1297 attrs->assignment_str[attrs->n_assignments++] = assignment; 1298 } 1299 out: 1300 return ret; 1301 } 1302 1303 static struct hist_trigger_attrs * 1304 parse_hist_trigger_attrs(struct trace_array *tr, char *trigger_str) 1305 { 1306 struct hist_trigger_attrs *attrs; 1307 int ret = 0; 1308 1309 attrs = kzalloc(sizeof(*attrs), GFP_KERNEL); 1310 if (!attrs) 1311 return ERR_PTR(-ENOMEM); 1312 1313 while (trigger_str) { 1314 char *str = strsep(&trigger_str, ":"); 1315 char *rhs; 1316 1317 rhs = strchr(str, '='); 1318 if (rhs) { 1319 if (!strlen(++rhs)) { 1320 ret = -EINVAL; 1321 hist_err(tr, HIST_ERR_EMPTY_ASSIGNMENT, errpos(str)); 1322 goto free; 1323 } 1324 ret = parse_assignment(tr, str, attrs); 1325 if (ret) 1326 goto free; 1327 } else if (strcmp(str, "pause") == 0) 1328 attrs->pause = true; 1329 else if ((strcmp(str, "cont") == 0) || 1330 (strcmp(str, "continue") == 0)) 1331 attrs->cont = true; 1332 else if (strcmp(str, "clear") == 0) 1333 attrs->clear = true; 1334 else { 1335 ret = parse_action(str, attrs); 1336 if (ret) 1337 goto free; 1338 } 1339 } 1340 1341 if (!attrs->keys_str) { 1342 ret = -EINVAL; 1343 goto free; 1344 } 1345 1346 if (!attrs->clock) { 1347 attrs->clock = kstrdup("global", GFP_KERNEL); 1348 if (!attrs->clock) { 1349 ret = -ENOMEM; 1350 goto free; 1351 } 1352 } 1353 1354 return attrs; 1355 free: 1356 destroy_hist_trigger_attrs(attrs); 1357 1358 return ERR_PTR(ret); 1359 } 1360 1361 static inline void save_comm(char *comm, struct task_struct *task) 1362 { 1363 if (!task->pid) { 1364 strcpy(comm, "<idle>"); 1365 return; 1366 } 1367 1368 if (WARN_ON_ONCE(task->pid < 0)) { 1369 strcpy(comm, "<XXX>"); 1370 return; 1371 } 1372 1373 strncpy(comm, task->comm, TASK_COMM_LEN); 1374 } 1375 1376 static void hist_elt_data_free(struct hist_elt_data *elt_data) 1377 { 1378 unsigned int i; 1379 1380 for (i = 0; i < SYNTH_FIELDS_MAX; i++) 1381 kfree(elt_data->field_var_str[i]); 1382 1383 kfree(elt_data->comm); 1384 kfree(elt_data); 1385 } 1386 1387 static void hist_trigger_elt_data_free(struct tracing_map_elt *elt) 1388 { 1389 struct hist_elt_data *elt_data = elt->private_data; 1390 1391 hist_elt_data_free(elt_data); 1392 } 1393 1394 static int hist_trigger_elt_data_alloc(struct tracing_map_elt *elt) 1395 { 1396 struct hist_trigger_data *hist_data = elt->map->private_data; 1397 unsigned int size = TASK_COMM_LEN; 1398 struct hist_elt_data *elt_data; 1399 struct hist_field *key_field; 1400 unsigned int i, n_str; 1401 1402 elt_data = kzalloc(sizeof(*elt_data), GFP_KERNEL); 1403 if (!elt_data) 1404 return -ENOMEM; 1405 1406 for_each_hist_key_field(i, hist_data) { 1407 key_field = hist_data->fields[i]; 1408 1409 if (key_field->flags & HIST_FIELD_FL_EXECNAME) { 1410 elt_data->comm = kzalloc(size, GFP_KERNEL); 1411 if (!elt_data->comm) { 1412 kfree(elt_data); 1413 return -ENOMEM; 1414 } 1415 break; 1416 } 1417 } 1418 1419 n_str = hist_data->n_field_var_str + hist_data->n_save_var_str + 1420 hist_data->n_var_str; 1421 if (n_str > SYNTH_FIELDS_MAX) { 1422 hist_elt_data_free(elt_data); 1423 return -EINVAL; 1424 } 1425 1426 BUILD_BUG_ON(STR_VAR_LEN_MAX & (sizeof(u64) - 1)); 1427 1428 size = STR_VAR_LEN_MAX; 1429 1430 for (i = 0; i < n_str; i++) { 1431 elt_data->field_var_str[i] = kzalloc(size, GFP_KERNEL); 1432 if (!elt_data->field_var_str[i]) { 1433 hist_elt_data_free(elt_data); 1434 return -ENOMEM; 1435 } 1436 } 1437 1438 elt->private_data = elt_data; 1439 1440 return 0; 1441 } 1442 1443 static void hist_trigger_elt_data_init(struct tracing_map_elt *elt) 1444 { 1445 struct hist_elt_data *elt_data = elt->private_data; 1446 1447 if (elt_data->comm) 1448 save_comm(elt_data->comm, current); 1449 } 1450 1451 static const struct tracing_map_ops hist_trigger_elt_data_ops = { 1452 .elt_alloc = hist_trigger_elt_data_alloc, 1453 .elt_free = hist_trigger_elt_data_free, 1454 .elt_init = hist_trigger_elt_data_init, 1455 }; 1456 1457 static const char *get_hist_field_flags(struct hist_field *hist_field) 1458 { 1459 const char *flags_str = NULL; 1460 1461 if (hist_field->flags & HIST_FIELD_FL_HEX) 1462 flags_str = "hex"; 1463 else if (hist_field->flags & HIST_FIELD_FL_SYM) 1464 flags_str = "sym"; 1465 else if (hist_field->flags & HIST_FIELD_FL_SYM_OFFSET) 1466 flags_str = "sym-offset"; 1467 else if (hist_field->flags & HIST_FIELD_FL_EXECNAME) 1468 flags_str = "execname"; 1469 else if (hist_field->flags & HIST_FIELD_FL_SYSCALL) 1470 flags_str = "syscall"; 1471 else if (hist_field->flags & HIST_FIELD_FL_LOG2) 1472 flags_str = "log2"; 1473 else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP_USECS) 1474 flags_str = "usecs"; 1475 1476 return flags_str; 1477 } 1478 1479 static void expr_field_str(struct hist_field *field, char *expr) 1480 { 1481 if (field->flags & HIST_FIELD_FL_VAR_REF) 1482 strcat(expr, "$"); 1483 1484 strcat(expr, hist_field_name(field, 0)); 1485 1486 if (field->flags && !(field->flags & HIST_FIELD_FL_VAR_REF)) { 1487 const char *flags_str = get_hist_field_flags(field); 1488 1489 if (flags_str) { 1490 strcat(expr, "."); 1491 strcat(expr, flags_str); 1492 } 1493 } 1494 } 1495 1496 static char *expr_str(struct hist_field *field, unsigned int level) 1497 { 1498 char *expr; 1499 1500 if (level > 1) 1501 return NULL; 1502 1503 expr = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL); 1504 if (!expr) 1505 return NULL; 1506 1507 if (!field->operands[0]) { 1508 expr_field_str(field, expr); 1509 return expr; 1510 } 1511 1512 if (field->operator == FIELD_OP_UNARY_MINUS) { 1513 char *subexpr; 1514 1515 strcat(expr, "-("); 1516 subexpr = expr_str(field->operands[0], ++level); 1517 if (!subexpr) { 1518 kfree(expr); 1519 return NULL; 1520 } 1521 strcat(expr, subexpr); 1522 strcat(expr, ")"); 1523 1524 kfree(subexpr); 1525 1526 return expr; 1527 } 1528 1529 expr_field_str(field->operands[0], expr); 1530 1531 switch (field->operator) { 1532 case FIELD_OP_MINUS: 1533 strcat(expr, "-"); 1534 break; 1535 case FIELD_OP_PLUS: 1536 strcat(expr, "+"); 1537 break; 1538 default: 1539 kfree(expr); 1540 return NULL; 1541 } 1542 1543 expr_field_str(field->operands[1], expr); 1544 1545 return expr; 1546 } 1547 1548 static int contains_operator(char *str) 1549 { 1550 enum field_op_id field_op = FIELD_OP_NONE; 1551 char *op; 1552 1553 op = strpbrk(str, "+-"); 1554 if (!op) 1555 return FIELD_OP_NONE; 1556 1557 switch (*op) { 1558 case '-': 1559 /* 1560 * Unfortunately, the modifier ".sym-offset" 1561 * can confuse things. 1562 */ 1563 if (op - str >= 4 && !strncmp(op - 4, ".sym-offset", 11)) 1564 return FIELD_OP_NONE; 1565 1566 if (*str == '-') 1567 field_op = FIELD_OP_UNARY_MINUS; 1568 else 1569 field_op = FIELD_OP_MINUS; 1570 break; 1571 case '+': 1572 field_op = FIELD_OP_PLUS; 1573 break; 1574 default: 1575 break; 1576 } 1577 1578 return field_op; 1579 } 1580 1581 static void get_hist_field(struct hist_field *hist_field) 1582 { 1583 hist_field->ref++; 1584 } 1585 1586 static void __destroy_hist_field(struct hist_field *hist_field) 1587 { 1588 if (--hist_field->ref > 1) 1589 return; 1590 1591 kfree(hist_field->var.name); 1592 kfree(hist_field->name); 1593 kfree(hist_field->type); 1594 1595 kfree(hist_field->system); 1596 kfree(hist_field->event_name); 1597 1598 kfree(hist_field); 1599 } 1600 1601 static void destroy_hist_field(struct hist_field *hist_field, 1602 unsigned int level) 1603 { 1604 unsigned int i; 1605 1606 if (level > 3) 1607 return; 1608 1609 if (!hist_field) 1610 return; 1611 1612 if (hist_field->flags & HIST_FIELD_FL_VAR_REF) 1613 return; /* var refs will be destroyed separately */ 1614 1615 for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++) 1616 destroy_hist_field(hist_field->operands[i], level + 1); 1617 1618 __destroy_hist_field(hist_field); 1619 } 1620 1621 static struct hist_field *create_hist_field(struct hist_trigger_data *hist_data, 1622 struct ftrace_event_field *field, 1623 unsigned long flags, 1624 char *var_name) 1625 { 1626 struct hist_field *hist_field; 1627 1628 if (field && is_function_field(field)) 1629 return NULL; 1630 1631 hist_field = kzalloc(sizeof(struct hist_field), GFP_KERNEL); 1632 if (!hist_field) 1633 return NULL; 1634 1635 hist_field->ref = 1; 1636 1637 hist_field->hist_data = hist_data; 1638 1639 if (flags & HIST_FIELD_FL_EXPR || flags & HIST_FIELD_FL_ALIAS) 1640 goto out; /* caller will populate */ 1641 1642 if (flags & HIST_FIELD_FL_VAR_REF) { 1643 hist_field->fn = hist_field_var_ref; 1644 goto out; 1645 } 1646 1647 if (flags & HIST_FIELD_FL_HITCOUNT) { 1648 hist_field->fn = hist_field_counter; 1649 hist_field->size = sizeof(u64); 1650 hist_field->type = kstrdup("u64", GFP_KERNEL); 1651 if (!hist_field->type) 1652 goto free; 1653 goto out; 1654 } 1655 1656 if (flags & HIST_FIELD_FL_STACKTRACE) { 1657 hist_field->fn = hist_field_none; 1658 goto out; 1659 } 1660 1661 if (flags & HIST_FIELD_FL_LOG2) { 1662 unsigned long fl = flags & ~HIST_FIELD_FL_LOG2; 1663 hist_field->fn = hist_field_log2; 1664 hist_field->operands[0] = create_hist_field(hist_data, field, fl, NULL); 1665 hist_field->size = hist_field->operands[0]->size; 1666 hist_field->type = kstrdup(hist_field->operands[0]->type, GFP_KERNEL); 1667 if (!hist_field->type) 1668 goto free; 1669 goto out; 1670 } 1671 1672 if (flags & HIST_FIELD_FL_TIMESTAMP) { 1673 hist_field->fn = hist_field_timestamp; 1674 hist_field->size = sizeof(u64); 1675 hist_field->type = kstrdup("u64", GFP_KERNEL); 1676 if (!hist_field->type) 1677 goto free; 1678 goto out; 1679 } 1680 1681 if (flags & HIST_FIELD_FL_CPU) { 1682 hist_field->fn = hist_field_cpu; 1683 hist_field->size = sizeof(int); 1684 hist_field->type = kstrdup("unsigned int", GFP_KERNEL); 1685 if (!hist_field->type) 1686 goto free; 1687 goto out; 1688 } 1689 1690 if (WARN_ON_ONCE(!field)) 1691 goto out; 1692 1693 /* Pointers to strings are just pointers and dangerous to dereference */ 1694 if (is_string_field(field) && 1695 (field->filter_type != FILTER_PTR_STRING)) { 1696 flags |= HIST_FIELD_FL_STRING; 1697 1698 hist_field->size = MAX_FILTER_STR_VAL; 1699 hist_field->type = kstrdup(field->type, GFP_KERNEL); 1700 if (!hist_field->type) 1701 goto free; 1702 1703 if (field->filter_type == FILTER_STATIC_STRING) 1704 hist_field->fn = hist_field_string; 1705 else if (field->filter_type == FILTER_DYN_STRING) 1706 hist_field->fn = hist_field_dynstring; 1707 else 1708 hist_field->fn = hist_field_pstring; 1709 } else { 1710 hist_field->size = field->size; 1711 hist_field->is_signed = field->is_signed; 1712 hist_field->type = kstrdup(field->type, GFP_KERNEL); 1713 if (!hist_field->type) 1714 goto free; 1715 1716 hist_field->fn = select_value_fn(field->size, 1717 field->is_signed); 1718 if (!hist_field->fn) { 1719 destroy_hist_field(hist_field, 0); 1720 return NULL; 1721 } 1722 } 1723 out: 1724 hist_field->field = field; 1725 hist_field->flags = flags; 1726 1727 if (var_name) { 1728 hist_field->var.name = kstrdup(var_name, GFP_KERNEL); 1729 if (!hist_field->var.name) 1730 goto free; 1731 } 1732 1733 return hist_field; 1734 free: 1735 destroy_hist_field(hist_field, 0); 1736 return NULL; 1737 } 1738 1739 static void destroy_hist_fields(struct hist_trigger_data *hist_data) 1740 { 1741 unsigned int i; 1742 1743 for (i = 0; i < HIST_FIELDS_MAX; i++) { 1744 if (hist_data->fields[i]) { 1745 destroy_hist_field(hist_data->fields[i], 0); 1746 hist_data->fields[i] = NULL; 1747 } 1748 } 1749 1750 for (i = 0; i < hist_data->n_var_refs; i++) { 1751 WARN_ON(!(hist_data->var_refs[i]->flags & HIST_FIELD_FL_VAR_REF)); 1752 __destroy_hist_field(hist_data->var_refs[i]); 1753 hist_data->var_refs[i] = NULL; 1754 } 1755 } 1756 1757 static int init_var_ref(struct hist_field *ref_field, 1758 struct hist_field *var_field, 1759 char *system, char *event_name) 1760 { 1761 int err = 0; 1762 1763 ref_field->var.idx = var_field->var.idx; 1764 ref_field->var.hist_data = var_field->hist_data; 1765 ref_field->size = var_field->size; 1766 ref_field->is_signed = var_field->is_signed; 1767 ref_field->flags |= var_field->flags & 1768 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS); 1769 1770 if (system) { 1771 ref_field->system = kstrdup(system, GFP_KERNEL); 1772 if (!ref_field->system) 1773 return -ENOMEM; 1774 } 1775 1776 if (event_name) { 1777 ref_field->event_name = kstrdup(event_name, GFP_KERNEL); 1778 if (!ref_field->event_name) { 1779 err = -ENOMEM; 1780 goto free; 1781 } 1782 } 1783 1784 if (var_field->var.name) { 1785 ref_field->name = kstrdup(var_field->var.name, GFP_KERNEL); 1786 if (!ref_field->name) { 1787 err = -ENOMEM; 1788 goto free; 1789 } 1790 } else if (var_field->name) { 1791 ref_field->name = kstrdup(var_field->name, GFP_KERNEL); 1792 if (!ref_field->name) { 1793 err = -ENOMEM; 1794 goto free; 1795 } 1796 } 1797 1798 ref_field->type = kstrdup(var_field->type, GFP_KERNEL); 1799 if (!ref_field->type) { 1800 err = -ENOMEM; 1801 goto free; 1802 } 1803 out: 1804 return err; 1805 free: 1806 kfree(ref_field->system); 1807 kfree(ref_field->event_name); 1808 kfree(ref_field->name); 1809 1810 goto out; 1811 } 1812 1813 static int find_var_ref_idx(struct hist_trigger_data *hist_data, 1814 struct hist_field *var_field) 1815 { 1816 struct hist_field *ref_field; 1817 int i; 1818 1819 for (i = 0; i < hist_data->n_var_refs; i++) { 1820 ref_field = hist_data->var_refs[i]; 1821 if (ref_field->var.idx == var_field->var.idx && 1822 ref_field->var.hist_data == var_field->hist_data) 1823 return i; 1824 } 1825 1826 return -ENOENT; 1827 } 1828 1829 /** 1830 * create_var_ref - Create a variable reference and attach it to trigger 1831 * @hist_data: The trigger that will be referencing the variable 1832 * @var_field: The VAR field to create a reference to 1833 * @system: The optional system string 1834 * @event_name: The optional event_name string 1835 * 1836 * Given a variable hist_field, create a VAR_REF hist_field that 1837 * represents a reference to it. 1838 * 1839 * This function also adds the reference to the trigger that 1840 * now references the variable. 1841 * 1842 * Return: The VAR_REF field if successful, NULL if not 1843 */ 1844 static struct hist_field *create_var_ref(struct hist_trigger_data *hist_data, 1845 struct hist_field *var_field, 1846 char *system, char *event_name) 1847 { 1848 unsigned long flags = HIST_FIELD_FL_VAR_REF; 1849 struct hist_field *ref_field; 1850 int i; 1851 1852 /* Check if the variable already exists */ 1853 for (i = 0; i < hist_data->n_var_refs; i++) { 1854 ref_field = hist_data->var_refs[i]; 1855 if (ref_field->var.idx == var_field->var.idx && 1856 ref_field->var.hist_data == var_field->hist_data) { 1857 get_hist_field(ref_field); 1858 return ref_field; 1859 } 1860 } 1861 1862 ref_field = create_hist_field(var_field->hist_data, NULL, flags, NULL); 1863 if (ref_field) { 1864 if (init_var_ref(ref_field, var_field, system, event_name)) { 1865 destroy_hist_field(ref_field, 0); 1866 return NULL; 1867 } 1868 1869 hist_data->var_refs[hist_data->n_var_refs] = ref_field; 1870 ref_field->var_ref_idx = hist_data->n_var_refs++; 1871 } 1872 1873 return ref_field; 1874 } 1875 1876 static bool is_var_ref(char *var_name) 1877 { 1878 if (!var_name || strlen(var_name) < 2 || var_name[0] != '$') 1879 return false; 1880 1881 return true; 1882 } 1883 1884 static char *field_name_from_var(struct hist_trigger_data *hist_data, 1885 char *var_name) 1886 { 1887 char *name, *field; 1888 unsigned int i; 1889 1890 for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) { 1891 name = hist_data->attrs->var_defs.name[i]; 1892 1893 if (strcmp(var_name, name) == 0) { 1894 field = hist_data->attrs->var_defs.expr[i]; 1895 if (contains_operator(field) || is_var_ref(field)) 1896 continue; 1897 return field; 1898 } 1899 } 1900 1901 return NULL; 1902 } 1903 1904 static char *local_field_var_ref(struct hist_trigger_data *hist_data, 1905 char *system, char *event_name, 1906 char *var_name) 1907 { 1908 struct trace_event_call *call; 1909 1910 if (system && event_name) { 1911 call = hist_data->event_file->event_call; 1912 1913 if (strcmp(system, call->class->system) != 0) 1914 return NULL; 1915 1916 if (strcmp(event_name, trace_event_name(call)) != 0) 1917 return NULL; 1918 } 1919 1920 if (!!system != !!event_name) 1921 return NULL; 1922 1923 if (!is_var_ref(var_name)) 1924 return NULL; 1925 1926 var_name++; 1927 1928 return field_name_from_var(hist_data, var_name); 1929 } 1930 1931 static struct hist_field *parse_var_ref(struct hist_trigger_data *hist_data, 1932 char *system, char *event_name, 1933 char *var_name) 1934 { 1935 struct hist_field *var_field = NULL, *ref_field = NULL; 1936 struct trace_array *tr = hist_data->event_file->tr; 1937 1938 if (!is_var_ref(var_name)) 1939 return NULL; 1940 1941 var_name++; 1942 1943 var_field = find_event_var(hist_data, system, event_name, var_name); 1944 if (var_field) 1945 ref_field = create_var_ref(hist_data, var_field, 1946 system, event_name); 1947 1948 if (!ref_field) 1949 hist_err(tr, HIST_ERR_VAR_NOT_FOUND, errpos(var_name)); 1950 1951 return ref_field; 1952 } 1953 1954 static struct ftrace_event_field * 1955 parse_field(struct hist_trigger_data *hist_data, struct trace_event_file *file, 1956 char *field_str, unsigned long *flags) 1957 { 1958 struct ftrace_event_field *field = NULL; 1959 char *field_name, *modifier, *str; 1960 struct trace_array *tr = file->tr; 1961 1962 modifier = str = kstrdup(field_str, GFP_KERNEL); 1963 if (!modifier) 1964 return ERR_PTR(-ENOMEM); 1965 1966 field_name = strsep(&modifier, "."); 1967 if (modifier) { 1968 if (strcmp(modifier, "hex") == 0) 1969 *flags |= HIST_FIELD_FL_HEX; 1970 else if (strcmp(modifier, "sym") == 0) 1971 *flags |= HIST_FIELD_FL_SYM; 1972 else if (strcmp(modifier, "sym-offset") == 0) 1973 *flags |= HIST_FIELD_FL_SYM_OFFSET; 1974 else if ((strcmp(modifier, "execname") == 0) && 1975 (strcmp(field_name, "common_pid") == 0)) 1976 *flags |= HIST_FIELD_FL_EXECNAME; 1977 else if (strcmp(modifier, "syscall") == 0) 1978 *flags |= HIST_FIELD_FL_SYSCALL; 1979 else if (strcmp(modifier, "log2") == 0) 1980 *flags |= HIST_FIELD_FL_LOG2; 1981 else if (strcmp(modifier, "usecs") == 0) 1982 *flags |= HIST_FIELD_FL_TIMESTAMP_USECS; 1983 else { 1984 hist_err(tr, HIST_ERR_BAD_FIELD_MODIFIER, errpos(modifier)); 1985 field = ERR_PTR(-EINVAL); 1986 goto out; 1987 } 1988 } 1989 1990 if (strcmp(field_name, "common_timestamp") == 0) { 1991 *flags |= HIST_FIELD_FL_TIMESTAMP; 1992 hist_data->enable_timestamps = true; 1993 if (*flags & HIST_FIELD_FL_TIMESTAMP_USECS) 1994 hist_data->attrs->ts_in_usecs = true; 1995 } else if (strcmp(field_name, "common_cpu") == 0) 1996 *flags |= HIST_FIELD_FL_CPU; 1997 else { 1998 field = trace_find_event_field(file->event_call, field_name); 1999 if (!field || !field->size) { 2000 /* 2001 * For backward compatibility, if field_name 2002 * was "cpu", then we treat this the same as 2003 * common_cpu. 2004 */ 2005 if (strcmp(field_name, "cpu") == 0) { 2006 *flags |= HIST_FIELD_FL_CPU; 2007 } else { 2008 hist_err(tr, HIST_ERR_FIELD_NOT_FOUND, 2009 errpos(field_name)); 2010 field = ERR_PTR(-EINVAL); 2011 goto out; 2012 } 2013 } 2014 } 2015 out: 2016 kfree(str); 2017 2018 return field; 2019 } 2020 2021 static struct hist_field *create_alias(struct hist_trigger_data *hist_data, 2022 struct hist_field *var_ref, 2023 char *var_name) 2024 { 2025 struct hist_field *alias = NULL; 2026 unsigned long flags = HIST_FIELD_FL_ALIAS | HIST_FIELD_FL_VAR; 2027 2028 alias = create_hist_field(hist_data, NULL, flags, var_name); 2029 if (!alias) 2030 return NULL; 2031 2032 alias->fn = var_ref->fn; 2033 alias->operands[0] = var_ref; 2034 2035 if (init_var_ref(alias, var_ref, var_ref->system, var_ref->event_name)) { 2036 destroy_hist_field(alias, 0); 2037 return NULL; 2038 } 2039 2040 alias->var_ref_idx = var_ref->var_ref_idx; 2041 2042 return alias; 2043 } 2044 2045 static struct hist_field *parse_atom(struct hist_trigger_data *hist_data, 2046 struct trace_event_file *file, char *str, 2047 unsigned long *flags, char *var_name) 2048 { 2049 char *s, *ref_system = NULL, *ref_event = NULL, *ref_var = str; 2050 struct ftrace_event_field *field = NULL; 2051 struct hist_field *hist_field = NULL; 2052 int ret = 0; 2053 2054 s = strchr(str, '.'); 2055 if (s) { 2056 s = strchr(++s, '.'); 2057 if (s) { 2058 ref_system = strsep(&str, "."); 2059 if (!str) { 2060 ret = -EINVAL; 2061 goto out; 2062 } 2063 ref_event = strsep(&str, "."); 2064 if (!str) { 2065 ret = -EINVAL; 2066 goto out; 2067 } 2068 ref_var = str; 2069 } 2070 } 2071 2072 s = local_field_var_ref(hist_data, ref_system, ref_event, ref_var); 2073 if (!s) { 2074 hist_field = parse_var_ref(hist_data, ref_system, 2075 ref_event, ref_var); 2076 if (hist_field) { 2077 if (var_name) { 2078 hist_field = create_alias(hist_data, hist_field, var_name); 2079 if (!hist_field) { 2080 ret = -ENOMEM; 2081 goto out; 2082 } 2083 } 2084 return hist_field; 2085 } 2086 } else 2087 str = s; 2088 2089 field = parse_field(hist_data, file, str, flags); 2090 if (IS_ERR(field)) { 2091 ret = PTR_ERR(field); 2092 goto out; 2093 } 2094 2095 hist_field = create_hist_field(hist_data, field, *flags, var_name); 2096 if (!hist_field) { 2097 ret = -ENOMEM; 2098 goto out; 2099 } 2100 2101 return hist_field; 2102 out: 2103 return ERR_PTR(ret); 2104 } 2105 2106 static struct hist_field *parse_expr(struct hist_trigger_data *hist_data, 2107 struct trace_event_file *file, 2108 char *str, unsigned long flags, 2109 char *var_name, unsigned int level); 2110 2111 static struct hist_field *parse_unary(struct hist_trigger_data *hist_data, 2112 struct trace_event_file *file, 2113 char *str, unsigned long flags, 2114 char *var_name, unsigned int level) 2115 { 2116 struct hist_field *operand1, *expr = NULL; 2117 unsigned long operand_flags; 2118 int ret = 0; 2119 char *s; 2120 2121 /* we support only -(xxx) i.e. explicit parens required */ 2122 2123 if (level > 3) { 2124 hist_err(file->tr, HIST_ERR_TOO_MANY_SUBEXPR, errpos(str)); 2125 ret = -EINVAL; 2126 goto free; 2127 } 2128 2129 str++; /* skip leading '-' */ 2130 2131 s = strchr(str, '('); 2132 if (s) 2133 str++; 2134 else { 2135 ret = -EINVAL; 2136 goto free; 2137 } 2138 2139 s = strrchr(str, ')'); 2140 if (s) 2141 *s = '\0'; 2142 else { 2143 ret = -EINVAL; /* no closing ')' */ 2144 goto free; 2145 } 2146 2147 flags |= HIST_FIELD_FL_EXPR; 2148 expr = create_hist_field(hist_data, NULL, flags, var_name); 2149 if (!expr) { 2150 ret = -ENOMEM; 2151 goto free; 2152 } 2153 2154 operand_flags = 0; 2155 operand1 = parse_expr(hist_data, file, str, operand_flags, NULL, ++level); 2156 if (IS_ERR(operand1)) { 2157 ret = PTR_ERR(operand1); 2158 goto free; 2159 } 2160 if (operand1->flags & HIST_FIELD_FL_STRING) { 2161 /* String type can not be the operand of unary operator. */ 2162 hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(str)); 2163 destroy_hist_field(operand1, 0); 2164 ret = -EINVAL; 2165 goto free; 2166 } 2167 2168 expr->flags |= operand1->flags & 2169 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS); 2170 expr->fn = hist_field_unary_minus; 2171 expr->operands[0] = operand1; 2172 expr->operator = FIELD_OP_UNARY_MINUS; 2173 expr->name = expr_str(expr, 0); 2174 expr->type = kstrdup(operand1->type, GFP_KERNEL); 2175 if (!expr->type) { 2176 ret = -ENOMEM; 2177 goto free; 2178 } 2179 2180 return expr; 2181 free: 2182 destroy_hist_field(expr, 0); 2183 return ERR_PTR(ret); 2184 } 2185 2186 static int check_expr_operands(struct trace_array *tr, 2187 struct hist_field *operand1, 2188 struct hist_field *operand2) 2189 { 2190 unsigned long operand1_flags = operand1->flags; 2191 unsigned long operand2_flags = operand2->flags; 2192 2193 if ((operand1_flags & HIST_FIELD_FL_VAR_REF) || 2194 (operand1_flags & HIST_FIELD_FL_ALIAS)) { 2195 struct hist_field *var; 2196 2197 var = find_var_field(operand1->var.hist_data, operand1->name); 2198 if (!var) 2199 return -EINVAL; 2200 operand1_flags = var->flags; 2201 } 2202 2203 if ((operand2_flags & HIST_FIELD_FL_VAR_REF) || 2204 (operand2_flags & HIST_FIELD_FL_ALIAS)) { 2205 struct hist_field *var; 2206 2207 var = find_var_field(operand2->var.hist_data, operand2->name); 2208 if (!var) 2209 return -EINVAL; 2210 operand2_flags = var->flags; 2211 } 2212 2213 if ((operand1_flags & HIST_FIELD_FL_TIMESTAMP_USECS) != 2214 (operand2_flags & HIST_FIELD_FL_TIMESTAMP_USECS)) { 2215 hist_err(tr, HIST_ERR_TIMESTAMP_MISMATCH, 0); 2216 return -EINVAL; 2217 } 2218 2219 return 0; 2220 } 2221 2222 static struct hist_field *parse_expr(struct hist_trigger_data *hist_data, 2223 struct trace_event_file *file, 2224 char *str, unsigned long flags, 2225 char *var_name, unsigned int level) 2226 { 2227 struct hist_field *operand1 = NULL, *operand2 = NULL, *expr = NULL; 2228 unsigned long operand_flags; 2229 int field_op, ret = -EINVAL; 2230 char *sep, *operand1_str; 2231 2232 if (level > 3) { 2233 hist_err(file->tr, HIST_ERR_TOO_MANY_SUBEXPR, errpos(str)); 2234 return ERR_PTR(-EINVAL); 2235 } 2236 2237 field_op = contains_operator(str); 2238 2239 if (field_op == FIELD_OP_NONE) 2240 return parse_atom(hist_data, file, str, &flags, var_name); 2241 2242 if (field_op == FIELD_OP_UNARY_MINUS) 2243 return parse_unary(hist_data, file, str, flags, var_name, ++level); 2244 2245 switch (field_op) { 2246 case FIELD_OP_MINUS: 2247 sep = "-"; 2248 break; 2249 case FIELD_OP_PLUS: 2250 sep = "+"; 2251 break; 2252 default: 2253 goto free; 2254 } 2255 2256 operand1_str = strsep(&str, sep); 2257 if (!operand1_str || !str) 2258 goto free; 2259 2260 operand_flags = 0; 2261 operand1 = parse_atom(hist_data, file, operand1_str, 2262 &operand_flags, NULL); 2263 if (IS_ERR(operand1)) { 2264 ret = PTR_ERR(operand1); 2265 operand1 = NULL; 2266 goto free; 2267 } 2268 if (operand1->flags & HIST_FIELD_FL_STRING) { 2269 hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(operand1_str)); 2270 ret = -EINVAL; 2271 goto free; 2272 } 2273 2274 /* rest of string could be another expression e.g. b+c in a+b+c */ 2275 operand_flags = 0; 2276 operand2 = parse_expr(hist_data, file, str, operand_flags, NULL, ++level); 2277 if (IS_ERR(operand2)) { 2278 ret = PTR_ERR(operand2); 2279 operand2 = NULL; 2280 goto free; 2281 } 2282 if (operand2->flags & HIST_FIELD_FL_STRING) { 2283 hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(str)); 2284 ret = -EINVAL; 2285 goto free; 2286 } 2287 2288 ret = check_expr_operands(file->tr, operand1, operand2); 2289 if (ret) 2290 goto free; 2291 2292 flags |= HIST_FIELD_FL_EXPR; 2293 2294 flags |= operand1->flags & 2295 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS); 2296 2297 expr = create_hist_field(hist_data, NULL, flags, var_name); 2298 if (!expr) { 2299 ret = -ENOMEM; 2300 goto free; 2301 } 2302 2303 operand1->read_once = true; 2304 operand2->read_once = true; 2305 2306 expr->operands[0] = operand1; 2307 expr->operands[1] = operand2; 2308 2309 /* The operand sizes should be the same, so just pick one */ 2310 expr->size = operand1->size; 2311 2312 expr->operator = field_op; 2313 expr->name = expr_str(expr, 0); 2314 expr->type = kstrdup(operand1->type, GFP_KERNEL); 2315 if (!expr->type) { 2316 ret = -ENOMEM; 2317 goto free; 2318 } 2319 2320 switch (field_op) { 2321 case FIELD_OP_MINUS: 2322 expr->fn = hist_field_minus; 2323 break; 2324 case FIELD_OP_PLUS: 2325 expr->fn = hist_field_plus; 2326 break; 2327 default: 2328 ret = -EINVAL; 2329 goto free; 2330 } 2331 2332 return expr; 2333 free: 2334 destroy_hist_field(operand1, 0); 2335 destroy_hist_field(operand2, 0); 2336 destroy_hist_field(expr, 0); 2337 2338 return ERR_PTR(ret); 2339 } 2340 2341 static char *find_trigger_filter(struct hist_trigger_data *hist_data, 2342 struct trace_event_file *file) 2343 { 2344 struct event_trigger_data *test; 2345 2346 lockdep_assert_held(&event_mutex); 2347 2348 list_for_each_entry(test, &file->triggers, list) { 2349 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 2350 if (test->private_data == hist_data) 2351 return test->filter_str; 2352 } 2353 } 2354 2355 return NULL; 2356 } 2357 2358 static struct event_command trigger_hist_cmd; 2359 static int event_hist_trigger_func(struct event_command *cmd_ops, 2360 struct trace_event_file *file, 2361 char *glob, char *cmd, char *param); 2362 2363 static bool compatible_keys(struct hist_trigger_data *target_hist_data, 2364 struct hist_trigger_data *hist_data, 2365 unsigned int n_keys) 2366 { 2367 struct hist_field *target_hist_field, *hist_field; 2368 unsigned int n, i, j; 2369 2370 if (hist_data->n_fields - hist_data->n_vals != n_keys) 2371 return false; 2372 2373 i = hist_data->n_vals; 2374 j = target_hist_data->n_vals; 2375 2376 for (n = 0; n < n_keys; n++) { 2377 hist_field = hist_data->fields[i + n]; 2378 target_hist_field = target_hist_data->fields[j + n]; 2379 2380 if (strcmp(hist_field->type, target_hist_field->type) != 0) 2381 return false; 2382 if (hist_field->size != target_hist_field->size) 2383 return false; 2384 if (hist_field->is_signed != target_hist_field->is_signed) 2385 return false; 2386 } 2387 2388 return true; 2389 } 2390 2391 static struct hist_trigger_data * 2392 find_compatible_hist(struct hist_trigger_data *target_hist_data, 2393 struct trace_event_file *file) 2394 { 2395 struct hist_trigger_data *hist_data; 2396 struct event_trigger_data *test; 2397 unsigned int n_keys; 2398 2399 lockdep_assert_held(&event_mutex); 2400 2401 n_keys = target_hist_data->n_fields - target_hist_data->n_vals; 2402 2403 list_for_each_entry(test, &file->triggers, list) { 2404 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 2405 hist_data = test->private_data; 2406 2407 if (compatible_keys(target_hist_data, hist_data, n_keys)) 2408 return hist_data; 2409 } 2410 } 2411 2412 return NULL; 2413 } 2414 2415 static struct trace_event_file *event_file(struct trace_array *tr, 2416 char *system, char *event_name) 2417 { 2418 struct trace_event_file *file; 2419 2420 file = __find_event_file(tr, system, event_name); 2421 if (!file) 2422 return ERR_PTR(-EINVAL); 2423 2424 return file; 2425 } 2426 2427 static struct hist_field * 2428 find_synthetic_field_var(struct hist_trigger_data *target_hist_data, 2429 char *system, char *event_name, char *field_name) 2430 { 2431 struct hist_field *event_var; 2432 char *synthetic_name; 2433 2434 synthetic_name = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL); 2435 if (!synthetic_name) 2436 return ERR_PTR(-ENOMEM); 2437 2438 strcpy(synthetic_name, "synthetic_"); 2439 strcat(synthetic_name, field_name); 2440 2441 event_var = find_event_var(target_hist_data, system, event_name, synthetic_name); 2442 2443 kfree(synthetic_name); 2444 2445 return event_var; 2446 } 2447 2448 /** 2449 * create_field_var_hist - Automatically create a histogram and var for a field 2450 * @target_hist_data: The target hist trigger 2451 * @subsys_name: Optional subsystem name 2452 * @event_name: Optional event name 2453 * @field_name: The name of the field (and the resulting variable) 2454 * 2455 * Hist trigger actions fetch data from variables, not directly from 2456 * events. However, for convenience, users are allowed to directly 2457 * specify an event field in an action, which will be automatically 2458 * converted into a variable on their behalf. 2459 2460 * If a user specifies a field on an event that isn't the event the 2461 * histogram currently being defined (the target event histogram), the 2462 * only way that can be accomplished is if a new hist trigger is 2463 * created and the field variable defined on that. 2464 * 2465 * This function creates a new histogram compatible with the target 2466 * event (meaning a histogram with the same key as the target 2467 * histogram), and creates a variable for the specified field, but 2468 * with 'synthetic_' prepended to the variable name in order to avoid 2469 * collision with normal field variables. 2470 * 2471 * Return: The variable created for the field. 2472 */ 2473 static struct hist_field * 2474 create_field_var_hist(struct hist_trigger_data *target_hist_data, 2475 char *subsys_name, char *event_name, char *field_name) 2476 { 2477 struct trace_array *tr = target_hist_data->event_file->tr; 2478 struct hist_trigger_data *hist_data; 2479 unsigned int i, n, first = true; 2480 struct field_var_hist *var_hist; 2481 struct trace_event_file *file; 2482 struct hist_field *key_field; 2483 struct hist_field *event_var; 2484 char *saved_filter; 2485 char *cmd; 2486 int ret; 2487 2488 if (target_hist_data->n_field_var_hists >= SYNTH_FIELDS_MAX) { 2489 hist_err(tr, HIST_ERR_TOO_MANY_FIELD_VARS, errpos(field_name)); 2490 return ERR_PTR(-EINVAL); 2491 } 2492 2493 file = event_file(tr, subsys_name, event_name); 2494 2495 if (IS_ERR(file)) { 2496 hist_err(tr, HIST_ERR_EVENT_FILE_NOT_FOUND, errpos(field_name)); 2497 ret = PTR_ERR(file); 2498 return ERR_PTR(ret); 2499 } 2500 2501 /* 2502 * Look for a histogram compatible with target. We'll use the 2503 * found histogram specification to create a new matching 2504 * histogram with our variable on it. target_hist_data is not 2505 * yet a registered histogram so we can't use that. 2506 */ 2507 hist_data = find_compatible_hist(target_hist_data, file); 2508 if (!hist_data) { 2509 hist_err(tr, HIST_ERR_HIST_NOT_FOUND, errpos(field_name)); 2510 return ERR_PTR(-EINVAL); 2511 } 2512 2513 /* See if a synthetic field variable has already been created */ 2514 event_var = find_synthetic_field_var(target_hist_data, subsys_name, 2515 event_name, field_name); 2516 if (!IS_ERR_OR_NULL(event_var)) 2517 return event_var; 2518 2519 var_hist = kzalloc(sizeof(*var_hist), GFP_KERNEL); 2520 if (!var_hist) 2521 return ERR_PTR(-ENOMEM); 2522 2523 cmd = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL); 2524 if (!cmd) { 2525 kfree(var_hist); 2526 return ERR_PTR(-ENOMEM); 2527 } 2528 2529 /* Use the same keys as the compatible histogram */ 2530 strcat(cmd, "keys="); 2531 2532 for_each_hist_key_field(i, hist_data) { 2533 key_field = hist_data->fields[i]; 2534 if (!first) 2535 strcat(cmd, ","); 2536 strcat(cmd, key_field->field->name); 2537 first = false; 2538 } 2539 2540 /* Create the synthetic field variable specification */ 2541 strcat(cmd, ":synthetic_"); 2542 strcat(cmd, field_name); 2543 strcat(cmd, "="); 2544 strcat(cmd, field_name); 2545 2546 /* Use the same filter as the compatible histogram */ 2547 saved_filter = find_trigger_filter(hist_data, file); 2548 if (saved_filter) { 2549 strcat(cmd, " if "); 2550 strcat(cmd, saved_filter); 2551 } 2552 2553 var_hist->cmd = kstrdup(cmd, GFP_KERNEL); 2554 if (!var_hist->cmd) { 2555 kfree(cmd); 2556 kfree(var_hist); 2557 return ERR_PTR(-ENOMEM); 2558 } 2559 2560 /* Save the compatible histogram information */ 2561 var_hist->hist_data = hist_data; 2562 2563 /* Create the new histogram with our variable */ 2564 ret = event_hist_trigger_func(&trigger_hist_cmd, file, 2565 "", "hist", cmd); 2566 if (ret) { 2567 kfree(cmd); 2568 kfree(var_hist->cmd); 2569 kfree(var_hist); 2570 hist_err(tr, HIST_ERR_HIST_CREATE_FAIL, errpos(field_name)); 2571 return ERR_PTR(ret); 2572 } 2573 2574 kfree(cmd); 2575 2576 /* If we can't find the variable, something went wrong */ 2577 event_var = find_synthetic_field_var(target_hist_data, subsys_name, 2578 event_name, field_name); 2579 if (IS_ERR_OR_NULL(event_var)) { 2580 kfree(var_hist->cmd); 2581 kfree(var_hist); 2582 hist_err(tr, HIST_ERR_SYNTH_VAR_NOT_FOUND, errpos(field_name)); 2583 return ERR_PTR(-EINVAL); 2584 } 2585 2586 n = target_hist_data->n_field_var_hists; 2587 target_hist_data->field_var_hists[n] = var_hist; 2588 target_hist_data->n_field_var_hists++; 2589 2590 return event_var; 2591 } 2592 2593 static struct hist_field * 2594 find_target_event_var(struct hist_trigger_data *hist_data, 2595 char *subsys_name, char *event_name, char *var_name) 2596 { 2597 struct trace_event_file *file = hist_data->event_file; 2598 struct hist_field *hist_field = NULL; 2599 2600 if (subsys_name) { 2601 struct trace_event_call *call; 2602 2603 if (!event_name) 2604 return NULL; 2605 2606 call = file->event_call; 2607 2608 if (strcmp(subsys_name, call->class->system) != 0) 2609 return NULL; 2610 2611 if (strcmp(event_name, trace_event_name(call)) != 0) 2612 return NULL; 2613 } 2614 2615 hist_field = find_var_field(hist_data, var_name); 2616 2617 return hist_field; 2618 } 2619 2620 static inline void __update_field_vars(struct tracing_map_elt *elt, 2621 struct trace_buffer *buffer, 2622 struct ring_buffer_event *rbe, 2623 void *rec, 2624 struct field_var **field_vars, 2625 unsigned int n_field_vars, 2626 unsigned int field_var_str_start) 2627 { 2628 struct hist_elt_data *elt_data = elt->private_data; 2629 unsigned int i, j, var_idx; 2630 u64 var_val; 2631 2632 for (i = 0, j = field_var_str_start; i < n_field_vars; i++) { 2633 struct field_var *field_var = field_vars[i]; 2634 struct hist_field *var = field_var->var; 2635 struct hist_field *val = field_var->val; 2636 2637 var_val = val->fn(val, elt, buffer, rbe, rec); 2638 var_idx = var->var.idx; 2639 2640 if (val->flags & HIST_FIELD_FL_STRING) { 2641 char *str = elt_data->field_var_str[j++]; 2642 char *val_str = (char *)(uintptr_t)var_val; 2643 2644 strscpy(str, val_str, STR_VAR_LEN_MAX); 2645 var_val = (u64)(uintptr_t)str; 2646 } 2647 tracing_map_set_var(elt, var_idx, var_val); 2648 } 2649 } 2650 2651 static void update_field_vars(struct hist_trigger_data *hist_data, 2652 struct tracing_map_elt *elt, 2653 struct trace_buffer *buffer, 2654 struct ring_buffer_event *rbe, 2655 void *rec) 2656 { 2657 __update_field_vars(elt, buffer, rbe, rec, hist_data->field_vars, 2658 hist_data->n_field_vars, 0); 2659 } 2660 2661 static void save_track_data_vars(struct hist_trigger_data *hist_data, 2662 struct tracing_map_elt *elt, 2663 struct trace_buffer *buffer, void *rec, 2664 struct ring_buffer_event *rbe, void *key, 2665 struct action_data *data, u64 *var_ref_vals) 2666 { 2667 __update_field_vars(elt, buffer, rbe, rec, hist_data->save_vars, 2668 hist_data->n_save_vars, hist_data->n_field_var_str); 2669 } 2670 2671 static struct hist_field *create_var(struct hist_trigger_data *hist_data, 2672 struct trace_event_file *file, 2673 char *name, int size, const char *type) 2674 { 2675 struct hist_field *var; 2676 int idx; 2677 2678 if (find_var(hist_data, file, name) && !hist_data->remove) { 2679 var = ERR_PTR(-EINVAL); 2680 goto out; 2681 } 2682 2683 var = kzalloc(sizeof(struct hist_field), GFP_KERNEL); 2684 if (!var) { 2685 var = ERR_PTR(-ENOMEM); 2686 goto out; 2687 } 2688 2689 idx = tracing_map_add_var(hist_data->map); 2690 if (idx < 0) { 2691 kfree(var); 2692 var = ERR_PTR(-EINVAL); 2693 goto out; 2694 } 2695 2696 var->ref = 1; 2697 var->flags = HIST_FIELD_FL_VAR; 2698 var->var.idx = idx; 2699 var->var.hist_data = var->hist_data = hist_data; 2700 var->size = size; 2701 var->var.name = kstrdup(name, GFP_KERNEL); 2702 var->type = kstrdup(type, GFP_KERNEL); 2703 if (!var->var.name || !var->type) { 2704 kfree(var->var.name); 2705 kfree(var->type); 2706 kfree(var); 2707 var = ERR_PTR(-ENOMEM); 2708 } 2709 out: 2710 return var; 2711 } 2712 2713 static struct field_var *create_field_var(struct hist_trigger_data *hist_data, 2714 struct trace_event_file *file, 2715 char *field_name) 2716 { 2717 struct hist_field *val = NULL, *var = NULL; 2718 unsigned long flags = HIST_FIELD_FL_VAR; 2719 struct trace_array *tr = file->tr; 2720 struct field_var *field_var; 2721 int ret = 0; 2722 2723 if (hist_data->n_field_vars >= SYNTH_FIELDS_MAX) { 2724 hist_err(tr, HIST_ERR_TOO_MANY_FIELD_VARS, errpos(field_name)); 2725 ret = -EINVAL; 2726 goto err; 2727 } 2728 2729 val = parse_atom(hist_data, file, field_name, &flags, NULL); 2730 if (IS_ERR(val)) { 2731 hist_err(tr, HIST_ERR_FIELD_VAR_PARSE_FAIL, errpos(field_name)); 2732 ret = PTR_ERR(val); 2733 goto err; 2734 } 2735 2736 var = create_var(hist_data, file, field_name, val->size, val->type); 2737 if (IS_ERR(var)) { 2738 hist_err(tr, HIST_ERR_VAR_CREATE_FIND_FAIL, errpos(field_name)); 2739 kfree(val); 2740 ret = PTR_ERR(var); 2741 goto err; 2742 } 2743 2744 field_var = kzalloc(sizeof(struct field_var), GFP_KERNEL); 2745 if (!field_var) { 2746 kfree(val); 2747 kfree(var); 2748 ret = -ENOMEM; 2749 goto err; 2750 } 2751 2752 field_var->var = var; 2753 field_var->val = val; 2754 out: 2755 return field_var; 2756 err: 2757 field_var = ERR_PTR(ret); 2758 goto out; 2759 } 2760 2761 /** 2762 * create_target_field_var - Automatically create a variable for a field 2763 * @target_hist_data: The target hist trigger 2764 * @subsys_name: Optional subsystem name 2765 * @event_name: Optional event name 2766 * @var_name: The name of the field (and the resulting variable) 2767 * 2768 * Hist trigger actions fetch data from variables, not directly from 2769 * events. However, for convenience, users are allowed to directly 2770 * specify an event field in an action, which will be automatically 2771 * converted into a variable on their behalf. 2772 2773 * This function creates a field variable with the name var_name on 2774 * the hist trigger currently being defined on the target event. If 2775 * subsys_name and event_name are specified, this function simply 2776 * verifies that they do in fact match the target event subsystem and 2777 * event name. 2778 * 2779 * Return: The variable created for the field. 2780 */ 2781 static struct field_var * 2782 create_target_field_var(struct hist_trigger_data *target_hist_data, 2783 char *subsys_name, char *event_name, char *var_name) 2784 { 2785 struct trace_event_file *file = target_hist_data->event_file; 2786 2787 if (subsys_name) { 2788 struct trace_event_call *call; 2789 2790 if (!event_name) 2791 return NULL; 2792 2793 call = file->event_call; 2794 2795 if (strcmp(subsys_name, call->class->system) != 0) 2796 return NULL; 2797 2798 if (strcmp(event_name, trace_event_name(call)) != 0) 2799 return NULL; 2800 } 2801 2802 return create_field_var(target_hist_data, file, var_name); 2803 } 2804 2805 static bool check_track_val_max(u64 track_val, u64 var_val) 2806 { 2807 if (var_val <= track_val) 2808 return false; 2809 2810 return true; 2811 } 2812 2813 static bool check_track_val_changed(u64 track_val, u64 var_val) 2814 { 2815 if (var_val == track_val) 2816 return false; 2817 2818 return true; 2819 } 2820 2821 static u64 get_track_val(struct hist_trigger_data *hist_data, 2822 struct tracing_map_elt *elt, 2823 struct action_data *data) 2824 { 2825 unsigned int track_var_idx = data->track_data.track_var->var.idx; 2826 u64 track_val; 2827 2828 track_val = tracing_map_read_var(elt, track_var_idx); 2829 2830 return track_val; 2831 } 2832 2833 static void save_track_val(struct hist_trigger_data *hist_data, 2834 struct tracing_map_elt *elt, 2835 struct action_data *data, u64 var_val) 2836 { 2837 unsigned int track_var_idx = data->track_data.track_var->var.idx; 2838 2839 tracing_map_set_var(elt, track_var_idx, var_val); 2840 } 2841 2842 static void save_track_data(struct hist_trigger_data *hist_data, 2843 struct tracing_map_elt *elt, 2844 struct trace_buffer *buffer, void *rec, 2845 struct ring_buffer_event *rbe, void *key, 2846 struct action_data *data, u64 *var_ref_vals) 2847 { 2848 if (data->track_data.save_data) 2849 data->track_data.save_data(hist_data, elt, buffer, rec, rbe, 2850 key, data, var_ref_vals); 2851 } 2852 2853 static bool check_track_val(struct tracing_map_elt *elt, 2854 struct action_data *data, 2855 u64 var_val) 2856 { 2857 struct hist_trigger_data *hist_data; 2858 u64 track_val; 2859 2860 hist_data = data->track_data.track_var->hist_data; 2861 track_val = get_track_val(hist_data, elt, data); 2862 2863 return data->track_data.check_val(track_val, var_val); 2864 } 2865 2866 #ifdef CONFIG_TRACER_SNAPSHOT 2867 static bool cond_snapshot_update(struct trace_array *tr, void *cond_data) 2868 { 2869 /* called with tr->max_lock held */ 2870 struct track_data *track_data = tr->cond_snapshot->cond_data; 2871 struct hist_elt_data *elt_data, *track_elt_data; 2872 struct snapshot_context *context = cond_data; 2873 struct action_data *action; 2874 u64 track_val; 2875 2876 if (!track_data) 2877 return false; 2878 2879 action = track_data->action_data; 2880 2881 track_val = get_track_val(track_data->hist_data, context->elt, 2882 track_data->action_data); 2883 2884 if (!action->track_data.check_val(track_data->track_val, track_val)) 2885 return false; 2886 2887 track_data->track_val = track_val; 2888 memcpy(track_data->key, context->key, track_data->key_len); 2889 2890 elt_data = context->elt->private_data; 2891 track_elt_data = track_data->elt.private_data; 2892 if (elt_data->comm) 2893 strncpy(track_elt_data->comm, elt_data->comm, TASK_COMM_LEN); 2894 2895 track_data->updated = true; 2896 2897 return true; 2898 } 2899 2900 static void save_track_data_snapshot(struct hist_trigger_data *hist_data, 2901 struct tracing_map_elt *elt, 2902 struct trace_buffer *buffer, void *rec, 2903 struct ring_buffer_event *rbe, void *key, 2904 struct action_data *data, 2905 u64 *var_ref_vals) 2906 { 2907 struct trace_event_file *file = hist_data->event_file; 2908 struct snapshot_context context; 2909 2910 context.elt = elt; 2911 context.key = key; 2912 2913 tracing_snapshot_cond(file->tr, &context); 2914 } 2915 2916 static void hist_trigger_print_key(struct seq_file *m, 2917 struct hist_trigger_data *hist_data, 2918 void *key, 2919 struct tracing_map_elt *elt); 2920 2921 static struct action_data *snapshot_action(struct hist_trigger_data *hist_data) 2922 { 2923 unsigned int i; 2924 2925 if (!hist_data->n_actions) 2926 return NULL; 2927 2928 for (i = 0; i < hist_data->n_actions; i++) { 2929 struct action_data *data = hist_data->actions[i]; 2930 2931 if (data->action == ACTION_SNAPSHOT) 2932 return data; 2933 } 2934 2935 return NULL; 2936 } 2937 2938 static void track_data_snapshot_print(struct seq_file *m, 2939 struct hist_trigger_data *hist_data) 2940 { 2941 struct trace_event_file *file = hist_data->event_file; 2942 struct track_data *track_data; 2943 struct action_data *action; 2944 2945 track_data = tracing_cond_snapshot_data(file->tr); 2946 if (!track_data) 2947 return; 2948 2949 if (!track_data->updated) 2950 return; 2951 2952 action = snapshot_action(hist_data); 2953 if (!action) 2954 return; 2955 2956 seq_puts(m, "\nSnapshot taken (see tracing/snapshot). Details:\n"); 2957 seq_printf(m, "\ttriggering value { %s(%s) }: %10llu", 2958 action->handler == HANDLER_ONMAX ? "onmax" : "onchange", 2959 action->track_data.var_str, track_data->track_val); 2960 2961 seq_puts(m, "\ttriggered by event with key: "); 2962 hist_trigger_print_key(m, hist_data, track_data->key, &track_data->elt); 2963 seq_putc(m, '\n'); 2964 } 2965 #else 2966 static bool cond_snapshot_update(struct trace_array *tr, void *cond_data) 2967 { 2968 return false; 2969 } 2970 static void save_track_data_snapshot(struct hist_trigger_data *hist_data, 2971 struct tracing_map_elt *elt, 2972 struct trace_buffer *buffer, void *rec, 2973 struct ring_buffer_event *rbe, void *key, 2974 struct action_data *data, 2975 u64 *var_ref_vals) {} 2976 static void track_data_snapshot_print(struct seq_file *m, 2977 struct hist_trigger_data *hist_data) {} 2978 #endif /* CONFIG_TRACER_SNAPSHOT */ 2979 2980 static void track_data_print(struct seq_file *m, 2981 struct hist_trigger_data *hist_data, 2982 struct tracing_map_elt *elt, 2983 struct action_data *data) 2984 { 2985 u64 track_val = get_track_val(hist_data, elt, data); 2986 unsigned int i, save_var_idx; 2987 2988 if (data->handler == HANDLER_ONMAX) 2989 seq_printf(m, "\n\tmax: %10llu", track_val); 2990 else if (data->handler == HANDLER_ONCHANGE) 2991 seq_printf(m, "\n\tchanged: %10llu", track_val); 2992 2993 if (data->action == ACTION_SNAPSHOT) 2994 return; 2995 2996 for (i = 0; i < hist_data->n_save_vars; i++) { 2997 struct hist_field *save_val = hist_data->save_vars[i]->val; 2998 struct hist_field *save_var = hist_data->save_vars[i]->var; 2999 u64 val; 3000 3001 save_var_idx = save_var->var.idx; 3002 3003 val = tracing_map_read_var(elt, save_var_idx); 3004 3005 if (save_val->flags & HIST_FIELD_FL_STRING) { 3006 seq_printf(m, " %s: %-32s", save_var->var.name, 3007 (char *)(uintptr_t)(val)); 3008 } else 3009 seq_printf(m, " %s: %10llu", save_var->var.name, val); 3010 } 3011 } 3012 3013 static void ontrack_action(struct hist_trigger_data *hist_data, 3014 struct tracing_map_elt *elt, 3015 struct trace_buffer *buffer, void *rec, 3016 struct ring_buffer_event *rbe, void *key, 3017 struct action_data *data, u64 *var_ref_vals) 3018 { 3019 u64 var_val = var_ref_vals[data->track_data.var_ref->var_ref_idx]; 3020 3021 if (check_track_val(elt, data, var_val)) { 3022 save_track_val(hist_data, elt, data, var_val); 3023 save_track_data(hist_data, elt, buffer, rec, rbe, 3024 key, data, var_ref_vals); 3025 } 3026 } 3027 3028 static void action_data_destroy(struct action_data *data) 3029 { 3030 unsigned int i; 3031 3032 lockdep_assert_held(&event_mutex); 3033 3034 kfree(data->action_name); 3035 3036 for (i = 0; i < data->n_params; i++) 3037 kfree(data->params[i]); 3038 3039 if (data->synth_event) 3040 data->synth_event->ref--; 3041 3042 kfree(data->synth_event_name); 3043 3044 kfree(data); 3045 } 3046 3047 static void track_data_destroy(struct hist_trigger_data *hist_data, 3048 struct action_data *data) 3049 { 3050 struct trace_event_file *file = hist_data->event_file; 3051 3052 destroy_hist_field(data->track_data.track_var, 0); 3053 3054 if (data->action == ACTION_SNAPSHOT) { 3055 struct track_data *track_data; 3056 3057 track_data = tracing_cond_snapshot_data(file->tr); 3058 if (track_data && track_data->hist_data == hist_data) { 3059 tracing_snapshot_cond_disable(file->tr); 3060 track_data_free(track_data); 3061 } 3062 } 3063 3064 kfree(data->track_data.var_str); 3065 3066 action_data_destroy(data); 3067 } 3068 3069 static int action_create(struct hist_trigger_data *hist_data, 3070 struct action_data *data); 3071 3072 static int track_data_create(struct hist_trigger_data *hist_data, 3073 struct action_data *data) 3074 { 3075 struct hist_field *var_field, *ref_field, *track_var = NULL; 3076 struct trace_event_file *file = hist_data->event_file; 3077 struct trace_array *tr = file->tr; 3078 char *track_data_var_str; 3079 int ret = 0; 3080 3081 track_data_var_str = data->track_data.var_str; 3082 if (track_data_var_str[0] != '$') { 3083 hist_err(tr, HIST_ERR_ONX_NOT_VAR, errpos(track_data_var_str)); 3084 return -EINVAL; 3085 } 3086 track_data_var_str++; 3087 3088 var_field = find_target_event_var(hist_data, NULL, NULL, track_data_var_str); 3089 if (!var_field) { 3090 hist_err(tr, HIST_ERR_ONX_VAR_NOT_FOUND, errpos(track_data_var_str)); 3091 return -EINVAL; 3092 } 3093 3094 ref_field = create_var_ref(hist_data, var_field, NULL, NULL); 3095 if (!ref_field) 3096 return -ENOMEM; 3097 3098 data->track_data.var_ref = ref_field; 3099 3100 if (data->handler == HANDLER_ONMAX) 3101 track_var = create_var(hist_data, file, "__max", sizeof(u64), "u64"); 3102 if (IS_ERR(track_var)) { 3103 hist_err(tr, HIST_ERR_ONX_VAR_CREATE_FAIL, 0); 3104 ret = PTR_ERR(track_var); 3105 goto out; 3106 } 3107 3108 if (data->handler == HANDLER_ONCHANGE) 3109 track_var = create_var(hist_data, file, "__change", sizeof(u64), "u64"); 3110 if (IS_ERR(track_var)) { 3111 hist_err(tr, HIST_ERR_ONX_VAR_CREATE_FAIL, 0); 3112 ret = PTR_ERR(track_var); 3113 goto out; 3114 } 3115 data->track_data.track_var = track_var; 3116 3117 ret = action_create(hist_data, data); 3118 out: 3119 return ret; 3120 } 3121 3122 static int parse_action_params(struct trace_array *tr, char *params, 3123 struct action_data *data) 3124 { 3125 char *param, *saved_param; 3126 bool first_param = true; 3127 int ret = 0; 3128 3129 while (params) { 3130 if (data->n_params >= SYNTH_FIELDS_MAX) { 3131 hist_err(tr, HIST_ERR_TOO_MANY_PARAMS, 0); 3132 goto out; 3133 } 3134 3135 param = strsep(¶ms, ","); 3136 if (!param) { 3137 hist_err(tr, HIST_ERR_PARAM_NOT_FOUND, 0); 3138 ret = -EINVAL; 3139 goto out; 3140 } 3141 3142 param = strstrip(param); 3143 if (strlen(param) < 2) { 3144 hist_err(tr, HIST_ERR_INVALID_PARAM, errpos(param)); 3145 ret = -EINVAL; 3146 goto out; 3147 } 3148 3149 saved_param = kstrdup(param, GFP_KERNEL); 3150 if (!saved_param) { 3151 ret = -ENOMEM; 3152 goto out; 3153 } 3154 3155 if (first_param && data->use_trace_keyword) { 3156 data->synth_event_name = saved_param; 3157 first_param = false; 3158 continue; 3159 } 3160 first_param = false; 3161 3162 data->params[data->n_params++] = saved_param; 3163 } 3164 out: 3165 return ret; 3166 } 3167 3168 static int action_parse(struct trace_array *tr, char *str, struct action_data *data, 3169 enum handler_id handler) 3170 { 3171 char *action_name; 3172 int ret = 0; 3173 3174 strsep(&str, "."); 3175 if (!str) { 3176 hist_err(tr, HIST_ERR_ACTION_NOT_FOUND, 0); 3177 ret = -EINVAL; 3178 goto out; 3179 } 3180 3181 action_name = strsep(&str, "("); 3182 if (!action_name || !str) { 3183 hist_err(tr, HIST_ERR_ACTION_NOT_FOUND, 0); 3184 ret = -EINVAL; 3185 goto out; 3186 } 3187 3188 if (str_has_prefix(action_name, "save")) { 3189 char *params = strsep(&str, ")"); 3190 3191 if (!params) { 3192 hist_err(tr, HIST_ERR_NO_SAVE_PARAMS, 0); 3193 ret = -EINVAL; 3194 goto out; 3195 } 3196 3197 ret = parse_action_params(tr, params, data); 3198 if (ret) 3199 goto out; 3200 3201 if (handler == HANDLER_ONMAX) 3202 data->track_data.check_val = check_track_val_max; 3203 else if (handler == HANDLER_ONCHANGE) 3204 data->track_data.check_val = check_track_val_changed; 3205 else { 3206 hist_err(tr, HIST_ERR_ACTION_MISMATCH, errpos(action_name)); 3207 ret = -EINVAL; 3208 goto out; 3209 } 3210 3211 data->track_data.save_data = save_track_data_vars; 3212 data->fn = ontrack_action; 3213 data->action = ACTION_SAVE; 3214 } else if (str_has_prefix(action_name, "snapshot")) { 3215 char *params = strsep(&str, ")"); 3216 3217 if (!str) { 3218 hist_err(tr, HIST_ERR_NO_CLOSING_PAREN, errpos(params)); 3219 ret = -EINVAL; 3220 goto out; 3221 } 3222 3223 if (handler == HANDLER_ONMAX) 3224 data->track_data.check_val = check_track_val_max; 3225 else if (handler == HANDLER_ONCHANGE) 3226 data->track_data.check_val = check_track_val_changed; 3227 else { 3228 hist_err(tr, HIST_ERR_ACTION_MISMATCH, errpos(action_name)); 3229 ret = -EINVAL; 3230 goto out; 3231 } 3232 3233 data->track_data.save_data = save_track_data_snapshot; 3234 data->fn = ontrack_action; 3235 data->action = ACTION_SNAPSHOT; 3236 } else { 3237 char *params = strsep(&str, ")"); 3238 3239 if (str_has_prefix(action_name, "trace")) 3240 data->use_trace_keyword = true; 3241 3242 if (params) { 3243 ret = parse_action_params(tr, params, data); 3244 if (ret) 3245 goto out; 3246 } 3247 3248 if (handler == HANDLER_ONMAX) 3249 data->track_data.check_val = check_track_val_max; 3250 else if (handler == HANDLER_ONCHANGE) 3251 data->track_data.check_val = check_track_val_changed; 3252 3253 if (handler != HANDLER_ONMATCH) { 3254 data->track_data.save_data = action_trace; 3255 data->fn = ontrack_action; 3256 } else 3257 data->fn = action_trace; 3258 3259 data->action = ACTION_TRACE; 3260 } 3261 3262 data->action_name = kstrdup(action_name, GFP_KERNEL); 3263 if (!data->action_name) { 3264 ret = -ENOMEM; 3265 goto out; 3266 } 3267 3268 data->handler = handler; 3269 out: 3270 return ret; 3271 } 3272 3273 static struct action_data *track_data_parse(struct hist_trigger_data *hist_data, 3274 char *str, enum handler_id handler) 3275 { 3276 struct action_data *data; 3277 int ret = -EINVAL; 3278 char *var_str; 3279 3280 data = kzalloc(sizeof(*data), GFP_KERNEL); 3281 if (!data) 3282 return ERR_PTR(-ENOMEM); 3283 3284 var_str = strsep(&str, ")"); 3285 if (!var_str || !str) { 3286 ret = -EINVAL; 3287 goto free; 3288 } 3289 3290 data->track_data.var_str = kstrdup(var_str, GFP_KERNEL); 3291 if (!data->track_data.var_str) { 3292 ret = -ENOMEM; 3293 goto free; 3294 } 3295 3296 ret = action_parse(hist_data->event_file->tr, str, data, handler); 3297 if (ret) 3298 goto free; 3299 out: 3300 return data; 3301 free: 3302 track_data_destroy(hist_data, data); 3303 data = ERR_PTR(ret); 3304 goto out; 3305 } 3306 3307 static void onmatch_destroy(struct action_data *data) 3308 { 3309 kfree(data->match_data.event); 3310 kfree(data->match_data.event_system); 3311 3312 action_data_destroy(data); 3313 } 3314 3315 static void destroy_field_var(struct field_var *field_var) 3316 { 3317 if (!field_var) 3318 return; 3319 3320 destroy_hist_field(field_var->var, 0); 3321 destroy_hist_field(field_var->val, 0); 3322 3323 kfree(field_var); 3324 } 3325 3326 static void destroy_field_vars(struct hist_trigger_data *hist_data) 3327 { 3328 unsigned int i; 3329 3330 for (i = 0; i < hist_data->n_field_vars; i++) 3331 destroy_field_var(hist_data->field_vars[i]); 3332 3333 for (i = 0; i < hist_data->n_save_vars; i++) 3334 destroy_field_var(hist_data->save_vars[i]); 3335 } 3336 3337 static void save_field_var(struct hist_trigger_data *hist_data, 3338 struct field_var *field_var) 3339 { 3340 hist_data->field_vars[hist_data->n_field_vars++] = field_var; 3341 3342 if (field_var->val->flags & HIST_FIELD_FL_STRING) 3343 hist_data->n_field_var_str++; 3344 } 3345 3346 3347 static int check_synth_field(struct synth_event *event, 3348 struct hist_field *hist_field, 3349 unsigned int field_pos) 3350 { 3351 struct synth_field *field; 3352 3353 if (field_pos >= event->n_fields) 3354 return -EINVAL; 3355 3356 field = event->fields[field_pos]; 3357 3358 /* 3359 * A dynamic string synth field can accept static or 3360 * dynamic. A static string synth field can only accept a 3361 * same-sized static string, which is checked for later. 3362 */ 3363 if (strstr(hist_field->type, "char[") && field->is_string 3364 && field->is_dynamic) 3365 return 0; 3366 3367 if (strcmp(field->type, hist_field->type) != 0) { 3368 if (field->size != hist_field->size || 3369 field->is_signed != hist_field->is_signed) 3370 return -EINVAL; 3371 } 3372 3373 return 0; 3374 } 3375 3376 static struct hist_field * 3377 trace_action_find_var(struct hist_trigger_data *hist_data, 3378 struct action_data *data, 3379 char *system, char *event, char *var) 3380 { 3381 struct trace_array *tr = hist_data->event_file->tr; 3382 struct hist_field *hist_field; 3383 3384 var++; /* skip '$' */ 3385 3386 hist_field = find_target_event_var(hist_data, system, event, var); 3387 if (!hist_field) { 3388 if (!system && data->handler == HANDLER_ONMATCH) { 3389 system = data->match_data.event_system; 3390 event = data->match_data.event; 3391 } 3392 3393 hist_field = find_event_var(hist_data, system, event, var); 3394 } 3395 3396 if (!hist_field) 3397 hist_err(tr, HIST_ERR_PARAM_NOT_FOUND, errpos(var)); 3398 3399 return hist_field; 3400 } 3401 3402 static struct hist_field * 3403 trace_action_create_field_var(struct hist_trigger_data *hist_data, 3404 struct action_data *data, char *system, 3405 char *event, char *var) 3406 { 3407 struct hist_field *hist_field = NULL; 3408 struct field_var *field_var; 3409 3410 /* 3411 * First try to create a field var on the target event (the 3412 * currently being defined). This will create a variable for 3413 * unqualified fields on the target event, or if qualified, 3414 * target fields that have qualified names matching the target. 3415 */ 3416 field_var = create_target_field_var(hist_data, system, event, var); 3417 3418 if (field_var && !IS_ERR(field_var)) { 3419 save_field_var(hist_data, field_var); 3420 hist_field = field_var->var; 3421 } else { 3422 field_var = NULL; 3423 /* 3424 * If no explicit system.event is specified, default to 3425 * looking for fields on the onmatch(system.event.xxx) 3426 * event. 3427 */ 3428 if (!system && data->handler == HANDLER_ONMATCH) { 3429 system = data->match_data.event_system; 3430 event = data->match_data.event; 3431 } 3432 3433 if (!event) 3434 goto free; 3435 /* 3436 * At this point, we're looking at a field on another 3437 * event. Because we can't modify a hist trigger on 3438 * another event to add a variable for a field, we need 3439 * to create a new trigger on that event and create the 3440 * variable at the same time. 3441 */ 3442 hist_field = create_field_var_hist(hist_data, system, event, var); 3443 if (IS_ERR(hist_field)) 3444 goto free; 3445 } 3446 out: 3447 return hist_field; 3448 free: 3449 destroy_field_var(field_var); 3450 hist_field = NULL; 3451 goto out; 3452 } 3453 3454 static int trace_action_create(struct hist_trigger_data *hist_data, 3455 struct action_data *data) 3456 { 3457 struct trace_array *tr = hist_data->event_file->tr; 3458 char *event_name, *param, *system = NULL; 3459 struct hist_field *hist_field, *var_ref; 3460 unsigned int i; 3461 unsigned int field_pos = 0; 3462 struct synth_event *event; 3463 char *synth_event_name; 3464 int var_ref_idx, ret = 0; 3465 3466 lockdep_assert_held(&event_mutex); 3467 3468 if (data->use_trace_keyword) 3469 synth_event_name = data->synth_event_name; 3470 else 3471 synth_event_name = data->action_name; 3472 3473 event = find_synth_event(synth_event_name); 3474 if (!event) { 3475 hist_err(tr, HIST_ERR_SYNTH_EVENT_NOT_FOUND, errpos(synth_event_name)); 3476 return -EINVAL; 3477 } 3478 3479 event->ref++; 3480 3481 for (i = 0; i < data->n_params; i++) { 3482 char *p; 3483 3484 p = param = kstrdup(data->params[i], GFP_KERNEL); 3485 if (!param) { 3486 ret = -ENOMEM; 3487 goto err; 3488 } 3489 3490 system = strsep(¶m, "."); 3491 if (!param) { 3492 param = (char *)system; 3493 system = event_name = NULL; 3494 } else { 3495 event_name = strsep(¶m, "."); 3496 if (!param) { 3497 kfree(p); 3498 ret = -EINVAL; 3499 goto err; 3500 } 3501 } 3502 3503 if (param[0] == '$') 3504 hist_field = trace_action_find_var(hist_data, data, 3505 system, event_name, 3506 param); 3507 else 3508 hist_field = trace_action_create_field_var(hist_data, 3509 data, 3510 system, 3511 event_name, 3512 param); 3513 3514 if (!hist_field) { 3515 kfree(p); 3516 ret = -EINVAL; 3517 goto err; 3518 } 3519 3520 if (check_synth_field(event, hist_field, field_pos) == 0) { 3521 var_ref = create_var_ref(hist_data, hist_field, 3522 system, event_name); 3523 if (!var_ref) { 3524 kfree(p); 3525 ret = -ENOMEM; 3526 goto err; 3527 } 3528 3529 var_ref_idx = find_var_ref_idx(hist_data, var_ref); 3530 if (WARN_ON(var_ref_idx < 0)) { 3531 ret = var_ref_idx; 3532 goto err; 3533 } 3534 3535 data->var_ref_idx[i] = var_ref_idx; 3536 3537 field_pos++; 3538 kfree(p); 3539 continue; 3540 } 3541 3542 hist_err(tr, HIST_ERR_SYNTH_TYPE_MISMATCH, errpos(param)); 3543 kfree(p); 3544 ret = -EINVAL; 3545 goto err; 3546 } 3547 3548 if (field_pos != event->n_fields) { 3549 hist_err(tr, HIST_ERR_SYNTH_COUNT_MISMATCH, errpos(event->name)); 3550 ret = -EINVAL; 3551 goto err; 3552 } 3553 3554 data->synth_event = event; 3555 out: 3556 return ret; 3557 err: 3558 event->ref--; 3559 3560 goto out; 3561 } 3562 3563 static int action_create(struct hist_trigger_data *hist_data, 3564 struct action_data *data) 3565 { 3566 struct trace_event_file *file = hist_data->event_file; 3567 struct trace_array *tr = file->tr; 3568 struct track_data *track_data; 3569 struct field_var *field_var; 3570 unsigned int i; 3571 char *param; 3572 int ret = 0; 3573 3574 if (data->action == ACTION_TRACE) 3575 return trace_action_create(hist_data, data); 3576 3577 if (data->action == ACTION_SNAPSHOT) { 3578 track_data = track_data_alloc(hist_data->key_size, data, hist_data); 3579 if (IS_ERR(track_data)) { 3580 ret = PTR_ERR(track_data); 3581 goto out; 3582 } 3583 3584 ret = tracing_snapshot_cond_enable(file->tr, track_data, 3585 cond_snapshot_update); 3586 if (ret) 3587 track_data_free(track_data); 3588 3589 goto out; 3590 } 3591 3592 if (data->action == ACTION_SAVE) { 3593 if (hist_data->n_save_vars) { 3594 ret = -EEXIST; 3595 hist_err(tr, HIST_ERR_TOO_MANY_SAVE_ACTIONS, 0); 3596 goto out; 3597 } 3598 3599 for (i = 0; i < data->n_params; i++) { 3600 param = kstrdup(data->params[i], GFP_KERNEL); 3601 if (!param) { 3602 ret = -ENOMEM; 3603 goto out; 3604 } 3605 3606 field_var = create_target_field_var(hist_data, NULL, NULL, param); 3607 if (IS_ERR(field_var)) { 3608 hist_err(tr, HIST_ERR_FIELD_VAR_CREATE_FAIL, 3609 errpos(param)); 3610 ret = PTR_ERR(field_var); 3611 kfree(param); 3612 goto out; 3613 } 3614 3615 hist_data->save_vars[hist_data->n_save_vars++] = field_var; 3616 if (field_var->val->flags & HIST_FIELD_FL_STRING) 3617 hist_data->n_save_var_str++; 3618 kfree(param); 3619 } 3620 } 3621 out: 3622 return ret; 3623 } 3624 3625 static int onmatch_create(struct hist_trigger_data *hist_data, 3626 struct action_data *data) 3627 { 3628 return action_create(hist_data, data); 3629 } 3630 3631 static struct action_data *onmatch_parse(struct trace_array *tr, char *str) 3632 { 3633 char *match_event, *match_event_system; 3634 struct action_data *data; 3635 int ret = -EINVAL; 3636 3637 data = kzalloc(sizeof(*data), GFP_KERNEL); 3638 if (!data) 3639 return ERR_PTR(-ENOMEM); 3640 3641 match_event = strsep(&str, ")"); 3642 if (!match_event || !str) { 3643 hist_err(tr, HIST_ERR_NO_CLOSING_PAREN, errpos(match_event)); 3644 goto free; 3645 } 3646 3647 match_event_system = strsep(&match_event, "."); 3648 if (!match_event) { 3649 hist_err(tr, HIST_ERR_SUBSYS_NOT_FOUND, errpos(match_event_system)); 3650 goto free; 3651 } 3652 3653 if (IS_ERR(event_file(tr, match_event_system, match_event))) { 3654 hist_err(tr, HIST_ERR_INVALID_SUBSYS_EVENT, errpos(match_event)); 3655 goto free; 3656 } 3657 3658 data->match_data.event = kstrdup(match_event, GFP_KERNEL); 3659 if (!data->match_data.event) { 3660 ret = -ENOMEM; 3661 goto free; 3662 } 3663 3664 data->match_data.event_system = kstrdup(match_event_system, GFP_KERNEL); 3665 if (!data->match_data.event_system) { 3666 ret = -ENOMEM; 3667 goto free; 3668 } 3669 3670 ret = action_parse(tr, str, data, HANDLER_ONMATCH); 3671 if (ret) 3672 goto free; 3673 out: 3674 return data; 3675 free: 3676 onmatch_destroy(data); 3677 data = ERR_PTR(ret); 3678 goto out; 3679 } 3680 3681 static int create_hitcount_val(struct hist_trigger_data *hist_data) 3682 { 3683 hist_data->fields[HITCOUNT_IDX] = 3684 create_hist_field(hist_data, NULL, HIST_FIELD_FL_HITCOUNT, NULL); 3685 if (!hist_data->fields[HITCOUNT_IDX]) 3686 return -ENOMEM; 3687 3688 hist_data->n_vals++; 3689 hist_data->n_fields++; 3690 3691 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX)) 3692 return -EINVAL; 3693 3694 return 0; 3695 } 3696 3697 static int __create_val_field(struct hist_trigger_data *hist_data, 3698 unsigned int val_idx, 3699 struct trace_event_file *file, 3700 char *var_name, char *field_str, 3701 unsigned long flags) 3702 { 3703 struct hist_field *hist_field; 3704 int ret = 0; 3705 3706 hist_field = parse_expr(hist_data, file, field_str, flags, var_name, 0); 3707 if (IS_ERR(hist_field)) { 3708 ret = PTR_ERR(hist_field); 3709 goto out; 3710 } 3711 3712 hist_data->fields[val_idx] = hist_field; 3713 3714 ++hist_data->n_vals; 3715 ++hist_data->n_fields; 3716 3717 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX)) 3718 ret = -EINVAL; 3719 out: 3720 return ret; 3721 } 3722 3723 static int create_val_field(struct hist_trigger_data *hist_data, 3724 unsigned int val_idx, 3725 struct trace_event_file *file, 3726 char *field_str) 3727 { 3728 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX)) 3729 return -EINVAL; 3730 3731 return __create_val_field(hist_data, val_idx, file, NULL, field_str, 0); 3732 } 3733 3734 static int create_var_field(struct hist_trigger_data *hist_data, 3735 unsigned int val_idx, 3736 struct trace_event_file *file, 3737 char *var_name, char *expr_str) 3738 { 3739 struct trace_array *tr = hist_data->event_file->tr; 3740 unsigned long flags = 0; 3741 int ret; 3742 3743 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX)) 3744 return -EINVAL; 3745 3746 if (find_var(hist_data, file, var_name) && !hist_data->remove) { 3747 hist_err(tr, HIST_ERR_DUPLICATE_VAR, errpos(var_name)); 3748 return -EINVAL; 3749 } 3750 3751 flags |= HIST_FIELD_FL_VAR; 3752 hist_data->n_vars++; 3753 if (WARN_ON(hist_data->n_vars > TRACING_MAP_VARS_MAX)) 3754 return -EINVAL; 3755 3756 ret = __create_val_field(hist_data, val_idx, file, var_name, expr_str, flags); 3757 3758 if (!ret && hist_data->fields[val_idx]->flags & HIST_FIELD_FL_STRING) 3759 hist_data->fields[val_idx]->var_str_idx = hist_data->n_var_str++; 3760 3761 return ret; 3762 } 3763 3764 static int create_val_fields(struct hist_trigger_data *hist_data, 3765 struct trace_event_file *file) 3766 { 3767 char *fields_str, *field_str; 3768 unsigned int i, j = 1; 3769 int ret; 3770 3771 ret = create_hitcount_val(hist_data); 3772 if (ret) 3773 goto out; 3774 3775 fields_str = hist_data->attrs->vals_str; 3776 if (!fields_str) 3777 goto out; 3778 3779 for (i = 0, j = 1; i < TRACING_MAP_VALS_MAX && 3780 j < TRACING_MAP_VALS_MAX; i++) { 3781 field_str = strsep(&fields_str, ","); 3782 if (!field_str) 3783 break; 3784 3785 if (strcmp(field_str, "hitcount") == 0) 3786 continue; 3787 3788 ret = create_val_field(hist_data, j++, file, field_str); 3789 if (ret) 3790 goto out; 3791 } 3792 3793 if (fields_str && (strcmp(fields_str, "hitcount") != 0)) 3794 ret = -EINVAL; 3795 out: 3796 return ret; 3797 } 3798 3799 static int create_key_field(struct hist_trigger_data *hist_data, 3800 unsigned int key_idx, 3801 unsigned int key_offset, 3802 struct trace_event_file *file, 3803 char *field_str) 3804 { 3805 struct trace_array *tr = hist_data->event_file->tr; 3806 struct hist_field *hist_field = NULL; 3807 unsigned long flags = 0; 3808 unsigned int key_size; 3809 int ret = 0; 3810 3811 if (WARN_ON(key_idx >= HIST_FIELDS_MAX)) 3812 return -EINVAL; 3813 3814 flags |= HIST_FIELD_FL_KEY; 3815 3816 if (strcmp(field_str, "stacktrace") == 0) { 3817 flags |= HIST_FIELD_FL_STACKTRACE; 3818 key_size = sizeof(unsigned long) * HIST_STACKTRACE_DEPTH; 3819 hist_field = create_hist_field(hist_data, NULL, flags, NULL); 3820 } else { 3821 hist_field = parse_expr(hist_data, file, field_str, flags, 3822 NULL, 0); 3823 if (IS_ERR(hist_field)) { 3824 ret = PTR_ERR(hist_field); 3825 goto out; 3826 } 3827 3828 if (field_has_hist_vars(hist_field, 0)) { 3829 hist_err(tr, HIST_ERR_INVALID_REF_KEY, errpos(field_str)); 3830 destroy_hist_field(hist_field, 0); 3831 ret = -EINVAL; 3832 goto out; 3833 } 3834 3835 key_size = hist_field->size; 3836 } 3837 3838 hist_data->fields[key_idx] = hist_field; 3839 3840 key_size = ALIGN(key_size, sizeof(u64)); 3841 hist_data->fields[key_idx]->size = key_size; 3842 hist_data->fields[key_idx]->offset = key_offset; 3843 3844 hist_data->key_size += key_size; 3845 3846 if (hist_data->key_size > HIST_KEY_SIZE_MAX) { 3847 ret = -EINVAL; 3848 goto out; 3849 } 3850 3851 hist_data->n_keys++; 3852 hist_data->n_fields++; 3853 3854 if (WARN_ON(hist_data->n_keys > TRACING_MAP_KEYS_MAX)) 3855 return -EINVAL; 3856 3857 ret = key_size; 3858 out: 3859 return ret; 3860 } 3861 3862 static int create_key_fields(struct hist_trigger_data *hist_data, 3863 struct trace_event_file *file) 3864 { 3865 unsigned int i, key_offset = 0, n_vals = hist_data->n_vals; 3866 char *fields_str, *field_str; 3867 int ret = -EINVAL; 3868 3869 fields_str = hist_data->attrs->keys_str; 3870 if (!fields_str) 3871 goto out; 3872 3873 for (i = n_vals; i < n_vals + TRACING_MAP_KEYS_MAX; i++) { 3874 field_str = strsep(&fields_str, ","); 3875 if (!field_str) 3876 break; 3877 ret = create_key_field(hist_data, i, key_offset, 3878 file, field_str); 3879 if (ret < 0) 3880 goto out; 3881 key_offset += ret; 3882 } 3883 if (fields_str) { 3884 ret = -EINVAL; 3885 goto out; 3886 } 3887 ret = 0; 3888 out: 3889 return ret; 3890 } 3891 3892 static int create_var_fields(struct hist_trigger_data *hist_data, 3893 struct trace_event_file *file) 3894 { 3895 unsigned int i, j = hist_data->n_vals; 3896 int ret = 0; 3897 3898 unsigned int n_vars = hist_data->attrs->var_defs.n_vars; 3899 3900 for (i = 0; i < n_vars; i++) { 3901 char *var_name = hist_data->attrs->var_defs.name[i]; 3902 char *expr = hist_data->attrs->var_defs.expr[i]; 3903 3904 ret = create_var_field(hist_data, j++, file, var_name, expr); 3905 if (ret) 3906 goto out; 3907 } 3908 out: 3909 return ret; 3910 } 3911 3912 static void free_var_defs(struct hist_trigger_data *hist_data) 3913 { 3914 unsigned int i; 3915 3916 for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) { 3917 kfree(hist_data->attrs->var_defs.name[i]); 3918 kfree(hist_data->attrs->var_defs.expr[i]); 3919 } 3920 3921 hist_data->attrs->var_defs.n_vars = 0; 3922 } 3923 3924 static int parse_var_defs(struct hist_trigger_data *hist_data) 3925 { 3926 struct trace_array *tr = hist_data->event_file->tr; 3927 char *s, *str, *var_name, *field_str; 3928 unsigned int i, j, n_vars = 0; 3929 int ret = 0; 3930 3931 for (i = 0; i < hist_data->attrs->n_assignments; i++) { 3932 str = hist_data->attrs->assignment_str[i]; 3933 for (j = 0; j < TRACING_MAP_VARS_MAX; j++) { 3934 field_str = strsep(&str, ","); 3935 if (!field_str) 3936 break; 3937 3938 var_name = strsep(&field_str, "="); 3939 if (!var_name || !field_str) { 3940 hist_err(tr, HIST_ERR_MALFORMED_ASSIGNMENT, 3941 errpos(var_name)); 3942 ret = -EINVAL; 3943 goto free; 3944 } 3945 3946 if (n_vars == TRACING_MAP_VARS_MAX) { 3947 hist_err(tr, HIST_ERR_TOO_MANY_VARS, errpos(var_name)); 3948 ret = -EINVAL; 3949 goto free; 3950 } 3951 3952 s = kstrdup(var_name, GFP_KERNEL); 3953 if (!s) { 3954 ret = -ENOMEM; 3955 goto free; 3956 } 3957 hist_data->attrs->var_defs.name[n_vars] = s; 3958 3959 s = kstrdup(field_str, GFP_KERNEL); 3960 if (!s) { 3961 ret = -ENOMEM; 3962 goto free; 3963 } 3964 hist_data->attrs->var_defs.expr[n_vars++] = s; 3965 3966 hist_data->attrs->var_defs.n_vars = n_vars; 3967 } 3968 } 3969 3970 return ret; 3971 free: 3972 free_var_defs(hist_data); 3973 3974 return ret; 3975 } 3976 3977 static int create_hist_fields(struct hist_trigger_data *hist_data, 3978 struct trace_event_file *file) 3979 { 3980 int ret; 3981 3982 ret = parse_var_defs(hist_data); 3983 if (ret) 3984 goto out; 3985 3986 ret = create_val_fields(hist_data, file); 3987 if (ret) 3988 goto out; 3989 3990 ret = create_var_fields(hist_data, file); 3991 if (ret) 3992 goto out; 3993 3994 ret = create_key_fields(hist_data, file); 3995 if (ret) 3996 goto out; 3997 out: 3998 free_var_defs(hist_data); 3999 4000 return ret; 4001 } 4002 4003 static int is_descending(struct trace_array *tr, const char *str) 4004 { 4005 if (!str) 4006 return 0; 4007 4008 if (strcmp(str, "descending") == 0) 4009 return 1; 4010 4011 if (strcmp(str, "ascending") == 0) 4012 return 0; 4013 4014 hist_err(tr, HIST_ERR_INVALID_SORT_MODIFIER, errpos((char *)str)); 4015 4016 return -EINVAL; 4017 } 4018 4019 static int create_sort_keys(struct hist_trigger_data *hist_data) 4020 { 4021 struct trace_array *tr = hist_data->event_file->tr; 4022 char *fields_str = hist_data->attrs->sort_key_str; 4023 struct tracing_map_sort_key *sort_key; 4024 int descending, ret = 0; 4025 unsigned int i, j, k; 4026 4027 hist_data->n_sort_keys = 1; /* we always have at least one, hitcount */ 4028 4029 if (!fields_str) 4030 goto out; 4031 4032 for (i = 0; i < TRACING_MAP_SORT_KEYS_MAX; i++) { 4033 struct hist_field *hist_field; 4034 char *field_str, *field_name; 4035 const char *test_name; 4036 4037 sort_key = &hist_data->sort_keys[i]; 4038 4039 field_str = strsep(&fields_str, ","); 4040 if (!field_str) 4041 break; 4042 4043 if (!*field_str) { 4044 ret = -EINVAL; 4045 hist_err(tr, HIST_ERR_EMPTY_SORT_FIELD, errpos("sort=")); 4046 break; 4047 } 4048 4049 if ((i == TRACING_MAP_SORT_KEYS_MAX - 1) && fields_str) { 4050 hist_err(tr, HIST_ERR_TOO_MANY_SORT_FIELDS, errpos("sort=")); 4051 ret = -EINVAL; 4052 break; 4053 } 4054 4055 field_name = strsep(&field_str, "."); 4056 if (!field_name || !*field_name) { 4057 ret = -EINVAL; 4058 hist_err(tr, HIST_ERR_EMPTY_SORT_FIELD, errpos("sort=")); 4059 break; 4060 } 4061 4062 if (strcmp(field_name, "hitcount") == 0) { 4063 descending = is_descending(tr, field_str); 4064 if (descending < 0) { 4065 ret = descending; 4066 break; 4067 } 4068 sort_key->descending = descending; 4069 continue; 4070 } 4071 4072 for (j = 1, k = 1; j < hist_data->n_fields; j++) { 4073 unsigned int idx; 4074 4075 hist_field = hist_data->fields[j]; 4076 if (hist_field->flags & HIST_FIELD_FL_VAR) 4077 continue; 4078 4079 idx = k++; 4080 4081 test_name = hist_field_name(hist_field, 0); 4082 4083 if (strcmp(field_name, test_name) == 0) { 4084 sort_key->field_idx = idx; 4085 descending = is_descending(tr, field_str); 4086 if (descending < 0) { 4087 ret = descending; 4088 goto out; 4089 } 4090 sort_key->descending = descending; 4091 break; 4092 } 4093 } 4094 if (j == hist_data->n_fields) { 4095 ret = -EINVAL; 4096 hist_err(tr, HIST_ERR_INVALID_SORT_FIELD, errpos(field_name)); 4097 break; 4098 } 4099 } 4100 4101 hist_data->n_sort_keys = i; 4102 out: 4103 return ret; 4104 } 4105 4106 static void destroy_actions(struct hist_trigger_data *hist_data) 4107 { 4108 unsigned int i; 4109 4110 for (i = 0; i < hist_data->n_actions; i++) { 4111 struct action_data *data = hist_data->actions[i]; 4112 4113 if (data->handler == HANDLER_ONMATCH) 4114 onmatch_destroy(data); 4115 else if (data->handler == HANDLER_ONMAX || 4116 data->handler == HANDLER_ONCHANGE) 4117 track_data_destroy(hist_data, data); 4118 else 4119 kfree(data); 4120 } 4121 } 4122 4123 static int parse_actions(struct hist_trigger_data *hist_data) 4124 { 4125 struct trace_array *tr = hist_data->event_file->tr; 4126 struct action_data *data; 4127 unsigned int i; 4128 int ret = 0; 4129 char *str; 4130 int len; 4131 4132 for (i = 0; i < hist_data->attrs->n_actions; i++) { 4133 str = hist_data->attrs->action_str[i]; 4134 4135 if ((len = str_has_prefix(str, "onmatch("))) { 4136 char *action_str = str + len; 4137 4138 data = onmatch_parse(tr, action_str); 4139 if (IS_ERR(data)) { 4140 ret = PTR_ERR(data); 4141 break; 4142 } 4143 } else if ((len = str_has_prefix(str, "onmax("))) { 4144 char *action_str = str + len; 4145 4146 data = track_data_parse(hist_data, action_str, 4147 HANDLER_ONMAX); 4148 if (IS_ERR(data)) { 4149 ret = PTR_ERR(data); 4150 break; 4151 } 4152 } else if ((len = str_has_prefix(str, "onchange("))) { 4153 char *action_str = str + len; 4154 4155 data = track_data_parse(hist_data, action_str, 4156 HANDLER_ONCHANGE); 4157 if (IS_ERR(data)) { 4158 ret = PTR_ERR(data); 4159 break; 4160 } 4161 } else { 4162 ret = -EINVAL; 4163 break; 4164 } 4165 4166 hist_data->actions[hist_data->n_actions++] = data; 4167 } 4168 4169 return ret; 4170 } 4171 4172 static int create_actions(struct hist_trigger_data *hist_data) 4173 { 4174 struct action_data *data; 4175 unsigned int i; 4176 int ret = 0; 4177 4178 for (i = 0; i < hist_data->attrs->n_actions; i++) { 4179 data = hist_data->actions[i]; 4180 4181 if (data->handler == HANDLER_ONMATCH) { 4182 ret = onmatch_create(hist_data, data); 4183 if (ret) 4184 break; 4185 } else if (data->handler == HANDLER_ONMAX || 4186 data->handler == HANDLER_ONCHANGE) { 4187 ret = track_data_create(hist_data, data); 4188 if (ret) 4189 break; 4190 } else { 4191 ret = -EINVAL; 4192 break; 4193 } 4194 } 4195 4196 return ret; 4197 } 4198 4199 static void print_actions(struct seq_file *m, 4200 struct hist_trigger_data *hist_data, 4201 struct tracing_map_elt *elt) 4202 { 4203 unsigned int i; 4204 4205 for (i = 0; i < hist_data->n_actions; i++) { 4206 struct action_data *data = hist_data->actions[i]; 4207 4208 if (data->action == ACTION_SNAPSHOT) 4209 continue; 4210 4211 if (data->handler == HANDLER_ONMAX || 4212 data->handler == HANDLER_ONCHANGE) 4213 track_data_print(m, hist_data, elt, data); 4214 } 4215 } 4216 4217 static void print_action_spec(struct seq_file *m, 4218 struct hist_trigger_data *hist_data, 4219 struct action_data *data) 4220 { 4221 unsigned int i; 4222 4223 if (data->action == ACTION_SAVE) { 4224 for (i = 0; i < hist_data->n_save_vars; i++) { 4225 seq_printf(m, "%s", hist_data->save_vars[i]->var->var.name); 4226 if (i < hist_data->n_save_vars - 1) 4227 seq_puts(m, ","); 4228 } 4229 } else if (data->action == ACTION_TRACE) { 4230 if (data->use_trace_keyword) 4231 seq_printf(m, "%s", data->synth_event_name); 4232 for (i = 0; i < data->n_params; i++) { 4233 if (i || data->use_trace_keyword) 4234 seq_puts(m, ","); 4235 seq_printf(m, "%s", data->params[i]); 4236 } 4237 } 4238 } 4239 4240 static void print_track_data_spec(struct seq_file *m, 4241 struct hist_trigger_data *hist_data, 4242 struct action_data *data) 4243 { 4244 if (data->handler == HANDLER_ONMAX) 4245 seq_puts(m, ":onmax("); 4246 else if (data->handler == HANDLER_ONCHANGE) 4247 seq_puts(m, ":onchange("); 4248 seq_printf(m, "%s", data->track_data.var_str); 4249 seq_printf(m, ").%s(", data->action_name); 4250 4251 print_action_spec(m, hist_data, data); 4252 4253 seq_puts(m, ")"); 4254 } 4255 4256 static void print_onmatch_spec(struct seq_file *m, 4257 struct hist_trigger_data *hist_data, 4258 struct action_data *data) 4259 { 4260 seq_printf(m, ":onmatch(%s.%s).", data->match_data.event_system, 4261 data->match_data.event); 4262 4263 seq_printf(m, "%s(", data->action_name); 4264 4265 print_action_spec(m, hist_data, data); 4266 4267 seq_puts(m, ")"); 4268 } 4269 4270 static bool actions_match(struct hist_trigger_data *hist_data, 4271 struct hist_trigger_data *hist_data_test) 4272 { 4273 unsigned int i, j; 4274 4275 if (hist_data->n_actions != hist_data_test->n_actions) 4276 return false; 4277 4278 for (i = 0; i < hist_data->n_actions; i++) { 4279 struct action_data *data = hist_data->actions[i]; 4280 struct action_data *data_test = hist_data_test->actions[i]; 4281 char *action_name, *action_name_test; 4282 4283 if (data->handler != data_test->handler) 4284 return false; 4285 if (data->action != data_test->action) 4286 return false; 4287 4288 if (data->n_params != data_test->n_params) 4289 return false; 4290 4291 for (j = 0; j < data->n_params; j++) { 4292 if (strcmp(data->params[j], data_test->params[j]) != 0) 4293 return false; 4294 } 4295 4296 if (data->use_trace_keyword) 4297 action_name = data->synth_event_name; 4298 else 4299 action_name = data->action_name; 4300 4301 if (data_test->use_trace_keyword) 4302 action_name_test = data_test->synth_event_name; 4303 else 4304 action_name_test = data_test->action_name; 4305 4306 if (strcmp(action_name, action_name_test) != 0) 4307 return false; 4308 4309 if (data->handler == HANDLER_ONMATCH) { 4310 if (strcmp(data->match_data.event_system, 4311 data_test->match_data.event_system) != 0) 4312 return false; 4313 if (strcmp(data->match_data.event, 4314 data_test->match_data.event) != 0) 4315 return false; 4316 } else if (data->handler == HANDLER_ONMAX || 4317 data->handler == HANDLER_ONCHANGE) { 4318 if (strcmp(data->track_data.var_str, 4319 data_test->track_data.var_str) != 0) 4320 return false; 4321 } 4322 } 4323 4324 return true; 4325 } 4326 4327 4328 static void print_actions_spec(struct seq_file *m, 4329 struct hist_trigger_data *hist_data) 4330 { 4331 unsigned int i; 4332 4333 for (i = 0; i < hist_data->n_actions; i++) { 4334 struct action_data *data = hist_data->actions[i]; 4335 4336 if (data->handler == HANDLER_ONMATCH) 4337 print_onmatch_spec(m, hist_data, data); 4338 else if (data->handler == HANDLER_ONMAX || 4339 data->handler == HANDLER_ONCHANGE) 4340 print_track_data_spec(m, hist_data, data); 4341 } 4342 } 4343 4344 static void destroy_field_var_hists(struct hist_trigger_data *hist_data) 4345 { 4346 unsigned int i; 4347 4348 for (i = 0; i < hist_data->n_field_var_hists; i++) { 4349 kfree(hist_data->field_var_hists[i]->cmd); 4350 kfree(hist_data->field_var_hists[i]); 4351 } 4352 } 4353 4354 static void destroy_hist_data(struct hist_trigger_data *hist_data) 4355 { 4356 if (!hist_data) 4357 return; 4358 4359 destroy_hist_trigger_attrs(hist_data->attrs); 4360 destroy_hist_fields(hist_data); 4361 tracing_map_destroy(hist_data->map); 4362 4363 destroy_actions(hist_data); 4364 destroy_field_vars(hist_data); 4365 destroy_field_var_hists(hist_data); 4366 4367 kfree(hist_data); 4368 } 4369 4370 static int create_tracing_map_fields(struct hist_trigger_data *hist_data) 4371 { 4372 struct tracing_map *map = hist_data->map; 4373 struct ftrace_event_field *field; 4374 struct hist_field *hist_field; 4375 int i, idx = 0; 4376 4377 for_each_hist_field(i, hist_data) { 4378 hist_field = hist_data->fields[i]; 4379 if (hist_field->flags & HIST_FIELD_FL_KEY) { 4380 tracing_map_cmp_fn_t cmp_fn; 4381 4382 field = hist_field->field; 4383 4384 if (hist_field->flags & HIST_FIELD_FL_STACKTRACE) 4385 cmp_fn = tracing_map_cmp_none; 4386 else if (!field) 4387 cmp_fn = tracing_map_cmp_num(hist_field->size, 4388 hist_field->is_signed); 4389 else if (is_string_field(field)) 4390 cmp_fn = tracing_map_cmp_string; 4391 else 4392 cmp_fn = tracing_map_cmp_num(field->size, 4393 field->is_signed); 4394 idx = tracing_map_add_key_field(map, 4395 hist_field->offset, 4396 cmp_fn); 4397 } else if (!(hist_field->flags & HIST_FIELD_FL_VAR)) 4398 idx = tracing_map_add_sum_field(map); 4399 4400 if (idx < 0) 4401 return idx; 4402 4403 if (hist_field->flags & HIST_FIELD_FL_VAR) { 4404 idx = tracing_map_add_var(map); 4405 if (idx < 0) 4406 return idx; 4407 hist_field->var.idx = idx; 4408 hist_field->var.hist_data = hist_data; 4409 } 4410 } 4411 4412 return 0; 4413 } 4414 4415 static struct hist_trigger_data * 4416 create_hist_data(unsigned int map_bits, 4417 struct hist_trigger_attrs *attrs, 4418 struct trace_event_file *file, 4419 bool remove) 4420 { 4421 const struct tracing_map_ops *map_ops = NULL; 4422 struct hist_trigger_data *hist_data; 4423 int ret = 0; 4424 4425 hist_data = kzalloc(sizeof(*hist_data), GFP_KERNEL); 4426 if (!hist_data) 4427 return ERR_PTR(-ENOMEM); 4428 4429 hist_data->attrs = attrs; 4430 hist_data->remove = remove; 4431 hist_data->event_file = file; 4432 4433 ret = parse_actions(hist_data); 4434 if (ret) 4435 goto free; 4436 4437 ret = create_hist_fields(hist_data, file); 4438 if (ret) 4439 goto free; 4440 4441 ret = create_sort_keys(hist_data); 4442 if (ret) 4443 goto free; 4444 4445 map_ops = &hist_trigger_elt_data_ops; 4446 4447 hist_data->map = tracing_map_create(map_bits, hist_data->key_size, 4448 map_ops, hist_data); 4449 if (IS_ERR(hist_data->map)) { 4450 ret = PTR_ERR(hist_data->map); 4451 hist_data->map = NULL; 4452 goto free; 4453 } 4454 4455 ret = create_tracing_map_fields(hist_data); 4456 if (ret) 4457 goto free; 4458 out: 4459 return hist_data; 4460 free: 4461 hist_data->attrs = NULL; 4462 4463 destroy_hist_data(hist_data); 4464 4465 hist_data = ERR_PTR(ret); 4466 4467 goto out; 4468 } 4469 4470 static void hist_trigger_elt_update(struct hist_trigger_data *hist_data, 4471 struct tracing_map_elt *elt, 4472 struct trace_buffer *buffer, void *rec, 4473 struct ring_buffer_event *rbe, 4474 u64 *var_ref_vals) 4475 { 4476 struct hist_elt_data *elt_data; 4477 struct hist_field *hist_field; 4478 unsigned int i, var_idx; 4479 u64 hist_val; 4480 4481 elt_data = elt->private_data; 4482 elt_data->var_ref_vals = var_ref_vals; 4483 4484 for_each_hist_val_field(i, hist_data) { 4485 hist_field = hist_data->fields[i]; 4486 hist_val = hist_field->fn(hist_field, elt, buffer, rbe, rec); 4487 if (hist_field->flags & HIST_FIELD_FL_VAR) { 4488 var_idx = hist_field->var.idx; 4489 4490 if (hist_field->flags & HIST_FIELD_FL_STRING) { 4491 unsigned int str_start, var_str_idx, idx; 4492 char *str, *val_str; 4493 4494 str_start = hist_data->n_field_var_str + 4495 hist_data->n_save_var_str; 4496 var_str_idx = hist_field->var_str_idx; 4497 idx = str_start + var_str_idx; 4498 4499 str = elt_data->field_var_str[idx]; 4500 val_str = (char *)(uintptr_t)hist_val; 4501 strscpy(str, val_str, STR_VAR_LEN_MAX); 4502 4503 hist_val = (u64)(uintptr_t)str; 4504 } 4505 tracing_map_set_var(elt, var_idx, hist_val); 4506 continue; 4507 } 4508 tracing_map_update_sum(elt, i, hist_val); 4509 } 4510 4511 for_each_hist_key_field(i, hist_data) { 4512 hist_field = hist_data->fields[i]; 4513 if (hist_field->flags & HIST_FIELD_FL_VAR) { 4514 hist_val = hist_field->fn(hist_field, elt, buffer, rbe, rec); 4515 var_idx = hist_field->var.idx; 4516 tracing_map_set_var(elt, var_idx, hist_val); 4517 } 4518 } 4519 4520 update_field_vars(hist_data, elt, buffer, rbe, rec); 4521 } 4522 4523 static inline void add_to_key(char *compound_key, void *key, 4524 struct hist_field *key_field, void *rec) 4525 { 4526 size_t size = key_field->size; 4527 4528 if (key_field->flags & HIST_FIELD_FL_STRING) { 4529 struct ftrace_event_field *field; 4530 4531 field = key_field->field; 4532 if (field->filter_type == FILTER_DYN_STRING) 4533 size = *(u32 *)(rec + field->offset) >> 16; 4534 else if (field->filter_type == FILTER_STATIC_STRING) 4535 size = field->size; 4536 4537 /* ensure NULL-termination */ 4538 if (size > key_field->size - 1) 4539 size = key_field->size - 1; 4540 4541 strncpy(compound_key + key_field->offset, (char *)key, size); 4542 } else 4543 memcpy(compound_key + key_field->offset, key, size); 4544 } 4545 4546 static void 4547 hist_trigger_actions(struct hist_trigger_data *hist_data, 4548 struct tracing_map_elt *elt, 4549 struct trace_buffer *buffer, void *rec, 4550 struct ring_buffer_event *rbe, void *key, 4551 u64 *var_ref_vals) 4552 { 4553 struct action_data *data; 4554 unsigned int i; 4555 4556 for (i = 0; i < hist_data->n_actions; i++) { 4557 data = hist_data->actions[i]; 4558 data->fn(hist_data, elt, buffer, rec, rbe, key, data, var_ref_vals); 4559 } 4560 } 4561 4562 static void event_hist_trigger(struct event_trigger_data *data, 4563 struct trace_buffer *buffer, void *rec, 4564 struct ring_buffer_event *rbe) 4565 { 4566 struct hist_trigger_data *hist_data = data->private_data; 4567 bool use_compound_key = (hist_data->n_keys > 1); 4568 unsigned long entries[HIST_STACKTRACE_DEPTH]; 4569 u64 var_ref_vals[TRACING_MAP_VARS_MAX]; 4570 char compound_key[HIST_KEY_SIZE_MAX]; 4571 struct tracing_map_elt *elt = NULL; 4572 struct hist_field *key_field; 4573 u64 field_contents; 4574 void *key = NULL; 4575 unsigned int i; 4576 4577 memset(compound_key, 0, hist_data->key_size); 4578 4579 for_each_hist_key_field(i, hist_data) { 4580 key_field = hist_data->fields[i]; 4581 4582 if (key_field->flags & HIST_FIELD_FL_STACKTRACE) { 4583 memset(entries, 0, HIST_STACKTRACE_SIZE); 4584 stack_trace_save(entries, HIST_STACKTRACE_DEPTH, 4585 HIST_STACKTRACE_SKIP); 4586 key = entries; 4587 } else { 4588 field_contents = key_field->fn(key_field, elt, buffer, rbe, rec); 4589 if (key_field->flags & HIST_FIELD_FL_STRING) { 4590 key = (void *)(unsigned long)field_contents; 4591 use_compound_key = true; 4592 } else 4593 key = (void *)&field_contents; 4594 } 4595 4596 if (use_compound_key) 4597 add_to_key(compound_key, key, key_field, rec); 4598 } 4599 4600 if (use_compound_key) 4601 key = compound_key; 4602 4603 if (hist_data->n_var_refs && 4604 !resolve_var_refs(hist_data, key, var_ref_vals, false)) 4605 return; 4606 4607 elt = tracing_map_insert(hist_data->map, key); 4608 if (!elt) 4609 return; 4610 4611 hist_trigger_elt_update(hist_data, elt, buffer, rec, rbe, var_ref_vals); 4612 4613 if (resolve_var_refs(hist_data, key, var_ref_vals, true)) 4614 hist_trigger_actions(hist_data, elt, buffer, rec, rbe, key, var_ref_vals); 4615 } 4616 4617 static void hist_trigger_stacktrace_print(struct seq_file *m, 4618 unsigned long *stacktrace_entries, 4619 unsigned int max_entries) 4620 { 4621 char str[KSYM_SYMBOL_LEN]; 4622 unsigned int spaces = 8; 4623 unsigned int i; 4624 4625 for (i = 0; i < max_entries; i++) { 4626 if (!stacktrace_entries[i]) 4627 return; 4628 4629 seq_printf(m, "%*c", 1 + spaces, ' '); 4630 sprint_symbol(str, stacktrace_entries[i]); 4631 seq_printf(m, "%s\n", str); 4632 } 4633 } 4634 4635 static void hist_trigger_print_key(struct seq_file *m, 4636 struct hist_trigger_data *hist_data, 4637 void *key, 4638 struct tracing_map_elt *elt) 4639 { 4640 struct hist_field *key_field; 4641 char str[KSYM_SYMBOL_LEN]; 4642 bool multiline = false; 4643 const char *field_name; 4644 unsigned int i; 4645 u64 uval; 4646 4647 seq_puts(m, "{ "); 4648 4649 for_each_hist_key_field(i, hist_data) { 4650 key_field = hist_data->fields[i]; 4651 4652 if (i > hist_data->n_vals) 4653 seq_puts(m, ", "); 4654 4655 field_name = hist_field_name(key_field, 0); 4656 4657 if (key_field->flags & HIST_FIELD_FL_HEX) { 4658 uval = *(u64 *)(key + key_field->offset); 4659 seq_printf(m, "%s: %llx", field_name, uval); 4660 } else if (key_field->flags & HIST_FIELD_FL_SYM) { 4661 uval = *(u64 *)(key + key_field->offset); 4662 sprint_symbol_no_offset(str, uval); 4663 seq_printf(m, "%s: [%llx] %-45s", field_name, 4664 uval, str); 4665 } else if (key_field->flags & HIST_FIELD_FL_SYM_OFFSET) { 4666 uval = *(u64 *)(key + key_field->offset); 4667 sprint_symbol(str, uval); 4668 seq_printf(m, "%s: [%llx] %-55s", field_name, 4669 uval, str); 4670 } else if (key_field->flags & HIST_FIELD_FL_EXECNAME) { 4671 struct hist_elt_data *elt_data = elt->private_data; 4672 char *comm; 4673 4674 if (WARN_ON_ONCE(!elt_data)) 4675 return; 4676 4677 comm = elt_data->comm; 4678 4679 uval = *(u64 *)(key + key_field->offset); 4680 seq_printf(m, "%s: %-16s[%10llu]", field_name, 4681 comm, uval); 4682 } else if (key_field->flags & HIST_FIELD_FL_SYSCALL) { 4683 const char *syscall_name; 4684 4685 uval = *(u64 *)(key + key_field->offset); 4686 syscall_name = get_syscall_name(uval); 4687 if (!syscall_name) 4688 syscall_name = "unknown_syscall"; 4689 4690 seq_printf(m, "%s: %-30s[%3llu]", field_name, 4691 syscall_name, uval); 4692 } else if (key_field->flags & HIST_FIELD_FL_STACKTRACE) { 4693 seq_puts(m, "stacktrace:\n"); 4694 hist_trigger_stacktrace_print(m, 4695 key + key_field->offset, 4696 HIST_STACKTRACE_DEPTH); 4697 multiline = true; 4698 } else if (key_field->flags & HIST_FIELD_FL_LOG2) { 4699 seq_printf(m, "%s: ~ 2^%-2llu", field_name, 4700 *(u64 *)(key + key_field->offset)); 4701 } else if (key_field->flags & HIST_FIELD_FL_STRING) { 4702 seq_printf(m, "%s: %-50s", field_name, 4703 (char *)(key + key_field->offset)); 4704 } else { 4705 uval = *(u64 *)(key + key_field->offset); 4706 seq_printf(m, "%s: %10llu", field_name, uval); 4707 } 4708 } 4709 4710 if (!multiline) 4711 seq_puts(m, " "); 4712 4713 seq_puts(m, "}"); 4714 } 4715 4716 static void hist_trigger_entry_print(struct seq_file *m, 4717 struct hist_trigger_data *hist_data, 4718 void *key, 4719 struct tracing_map_elt *elt) 4720 { 4721 const char *field_name; 4722 unsigned int i; 4723 4724 hist_trigger_print_key(m, hist_data, key, elt); 4725 4726 seq_printf(m, " hitcount: %10llu", 4727 tracing_map_read_sum(elt, HITCOUNT_IDX)); 4728 4729 for (i = 1; i < hist_data->n_vals; i++) { 4730 field_name = hist_field_name(hist_data->fields[i], 0); 4731 4732 if (hist_data->fields[i]->flags & HIST_FIELD_FL_VAR || 4733 hist_data->fields[i]->flags & HIST_FIELD_FL_EXPR) 4734 continue; 4735 4736 if (hist_data->fields[i]->flags & HIST_FIELD_FL_HEX) { 4737 seq_printf(m, " %s: %10llx", field_name, 4738 tracing_map_read_sum(elt, i)); 4739 } else { 4740 seq_printf(m, " %s: %10llu", field_name, 4741 tracing_map_read_sum(elt, i)); 4742 } 4743 } 4744 4745 print_actions(m, hist_data, elt); 4746 4747 seq_puts(m, "\n"); 4748 } 4749 4750 static int print_entries(struct seq_file *m, 4751 struct hist_trigger_data *hist_data) 4752 { 4753 struct tracing_map_sort_entry **sort_entries = NULL; 4754 struct tracing_map *map = hist_data->map; 4755 int i, n_entries; 4756 4757 n_entries = tracing_map_sort_entries(map, hist_data->sort_keys, 4758 hist_data->n_sort_keys, 4759 &sort_entries); 4760 if (n_entries < 0) 4761 return n_entries; 4762 4763 for (i = 0; i < n_entries; i++) 4764 hist_trigger_entry_print(m, hist_data, 4765 sort_entries[i]->key, 4766 sort_entries[i]->elt); 4767 4768 tracing_map_destroy_sort_entries(sort_entries, n_entries); 4769 4770 return n_entries; 4771 } 4772 4773 static void hist_trigger_show(struct seq_file *m, 4774 struct event_trigger_data *data, int n) 4775 { 4776 struct hist_trigger_data *hist_data; 4777 int n_entries; 4778 4779 if (n > 0) 4780 seq_puts(m, "\n\n"); 4781 4782 seq_puts(m, "# event histogram\n#\n# trigger info: "); 4783 data->ops->print(m, data->ops, data); 4784 seq_puts(m, "#\n\n"); 4785 4786 hist_data = data->private_data; 4787 n_entries = print_entries(m, hist_data); 4788 if (n_entries < 0) 4789 n_entries = 0; 4790 4791 track_data_snapshot_print(m, hist_data); 4792 4793 seq_printf(m, "\nTotals:\n Hits: %llu\n Entries: %u\n Dropped: %llu\n", 4794 (u64)atomic64_read(&hist_data->map->hits), 4795 n_entries, (u64)atomic64_read(&hist_data->map->drops)); 4796 } 4797 4798 static int hist_show(struct seq_file *m, void *v) 4799 { 4800 struct event_trigger_data *data; 4801 struct trace_event_file *event_file; 4802 int n = 0, ret = 0; 4803 4804 mutex_lock(&event_mutex); 4805 4806 event_file = event_file_data(m->private); 4807 if (unlikely(!event_file)) { 4808 ret = -ENODEV; 4809 goto out_unlock; 4810 } 4811 4812 list_for_each_entry(data, &event_file->triggers, list) { 4813 if (data->cmd_ops->trigger_type == ETT_EVENT_HIST) 4814 hist_trigger_show(m, data, n++); 4815 } 4816 4817 out_unlock: 4818 mutex_unlock(&event_mutex); 4819 4820 return ret; 4821 } 4822 4823 static int event_hist_open(struct inode *inode, struct file *file) 4824 { 4825 int ret; 4826 4827 ret = security_locked_down(LOCKDOWN_TRACEFS); 4828 if (ret) 4829 return ret; 4830 4831 return single_open(file, hist_show, file); 4832 } 4833 4834 const struct file_operations event_hist_fops = { 4835 .open = event_hist_open, 4836 .read = seq_read, 4837 .llseek = seq_lseek, 4838 .release = single_release, 4839 }; 4840 4841 #ifdef CONFIG_HIST_TRIGGERS_DEBUG 4842 static void hist_field_debug_show_flags(struct seq_file *m, 4843 unsigned long flags) 4844 { 4845 seq_puts(m, " flags:\n"); 4846 4847 if (flags & HIST_FIELD_FL_KEY) 4848 seq_puts(m, " HIST_FIELD_FL_KEY\n"); 4849 else if (flags & HIST_FIELD_FL_HITCOUNT) 4850 seq_puts(m, " VAL: HIST_FIELD_FL_HITCOUNT\n"); 4851 else if (flags & HIST_FIELD_FL_VAR) 4852 seq_puts(m, " HIST_FIELD_FL_VAR\n"); 4853 else if (flags & HIST_FIELD_FL_VAR_REF) 4854 seq_puts(m, " HIST_FIELD_FL_VAR_REF\n"); 4855 else 4856 seq_puts(m, " VAL: normal u64 value\n"); 4857 4858 if (flags & HIST_FIELD_FL_ALIAS) 4859 seq_puts(m, " HIST_FIELD_FL_ALIAS\n"); 4860 } 4861 4862 static int hist_field_debug_show(struct seq_file *m, 4863 struct hist_field *field, unsigned long flags) 4864 { 4865 if ((field->flags & flags) != flags) { 4866 seq_printf(m, "ERROR: bad flags - %lx\n", flags); 4867 return -EINVAL; 4868 } 4869 4870 hist_field_debug_show_flags(m, field->flags); 4871 if (field->field) 4872 seq_printf(m, " ftrace_event_field name: %s\n", 4873 field->field->name); 4874 4875 if (field->flags & HIST_FIELD_FL_VAR) { 4876 seq_printf(m, " var.name: %s\n", field->var.name); 4877 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n", 4878 field->var.idx); 4879 } 4880 4881 if (field->flags & HIST_FIELD_FL_ALIAS) 4882 seq_printf(m, " var_ref_idx (into hist_data->var_refs[]): %u\n", 4883 field->var_ref_idx); 4884 4885 if (field->flags & HIST_FIELD_FL_VAR_REF) { 4886 seq_printf(m, " name: %s\n", field->name); 4887 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n", 4888 field->var.idx); 4889 seq_printf(m, " var.hist_data: %p\n", field->var.hist_data); 4890 seq_printf(m, " var_ref_idx (into hist_data->var_refs[]): %u\n", 4891 field->var_ref_idx); 4892 if (field->system) 4893 seq_printf(m, " system: %s\n", field->system); 4894 if (field->event_name) 4895 seq_printf(m, " event_name: %s\n", field->event_name); 4896 } 4897 4898 seq_printf(m, " type: %s\n", field->type); 4899 seq_printf(m, " size: %u\n", field->size); 4900 seq_printf(m, " is_signed: %u\n", field->is_signed); 4901 4902 return 0; 4903 } 4904 4905 static int field_var_debug_show(struct seq_file *m, 4906 struct field_var *field_var, unsigned int i, 4907 bool save_vars) 4908 { 4909 const char *vars_name = save_vars ? "save_vars" : "field_vars"; 4910 struct hist_field *field; 4911 int ret = 0; 4912 4913 seq_printf(m, "\n hist_data->%s[%d]:\n", vars_name, i); 4914 4915 field = field_var->var; 4916 4917 seq_printf(m, "\n %s[%d].var:\n", vars_name, i); 4918 4919 hist_field_debug_show_flags(m, field->flags); 4920 seq_printf(m, " var.name: %s\n", field->var.name); 4921 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n", 4922 field->var.idx); 4923 4924 field = field_var->val; 4925 4926 seq_printf(m, "\n %s[%d].val:\n", vars_name, i); 4927 if (field->field) 4928 seq_printf(m, " ftrace_event_field name: %s\n", 4929 field->field->name); 4930 else { 4931 ret = -EINVAL; 4932 goto out; 4933 } 4934 4935 seq_printf(m, " type: %s\n", field->type); 4936 seq_printf(m, " size: %u\n", field->size); 4937 seq_printf(m, " is_signed: %u\n", field->is_signed); 4938 out: 4939 return ret; 4940 } 4941 4942 static int hist_action_debug_show(struct seq_file *m, 4943 struct action_data *data, int i) 4944 { 4945 int ret = 0; 4946 4947 if (data->handler == HANDLER_ONMAX || 4948 data->handler == HANDLER_ONCHANGE) { 4949 seq_printf(m, "\n hist_data->actions[%d].track_data.var_ref:\n", i); 4950 ret = hist_field_debug_show(m, data->track_data.var_ref, 4951 HIST_FIELD_FL_VAR_REF); 4952 if (ret) 4953 goto out; 4954 4955 seq_printf(m, "\n hist_data->actions[%d].track_data.track_var:\n", i); 4956 ret = hist_field_debug_show(m, data->track_data.track_var, 4957 HIST_FIELD_FL_VAR); 4958 if (ret) 4959 goto out; 4960 } 4961 4962 if (data->handler == HANDLER_ONMATCH) { 4963 seq_printf(m, "\n hist_data->actions[%d].match_data.event_system: %s\n", 4964 i, data->match_data.event_system); 4965 seq_printf(m, " hist_data->actions[%d].match_data.event: %s\n", 4966 i, data->match_data.event); 4967 } 4968 out: 4969 return ret; 4970 } 4971 4972 static int hist_actions_debug_show(struct seq_file *m, 4973 struct hist_trigger_data *hist_data) 4974 { 4975 int i, ret = 0; 4976 4977 if (hist_data->n_actions) 4978 seq_puts(m, "\n action tracking variables (for onmax()/onchange()/onmatch()):\n"); 4979 4980 for (i = 0; i < hist_data->n_actions; i++) { 4981 struct action_data *action = hist_data->actions[i]; 4982 4983 ret = hist_action_debug_show(m, action, i); 4984 if (ret) 4985 goto out; 4986 } 4987 4988 if (hist_data->n_save_vars) 4989 seq_puts(m, "\n save action variables (save() params):\n"); 4990 4991 for (i = 0; i < hist_data->n_save_vars; i++) { 4992 ret = field_var_debug_show(m, hist_data->save_vars[i], i, true); 4993 if (ret) 4994 goto out; 4995 } 4996 out: 4997 return ret; 4998 } 4999 5000 static void hist_trigger_debug_show(struct seq_file *m, 5001 struct event_trigger_data *data, int n) 5002 { 5003 struct hist_trigger_data *hist_data; 5004 int i, ret; 5005 5006 if (n > 0) 5007 seq_puts(m, "\n\n"); 5008 5009 seq_puts(m, "# event histogram\n#\n# trigger info: "); 5010 data->ops->print(m, data->ops, data); 5011 seq_puts(m, "#\n\n"); 5012 5013 hist_data = data->private_data; 5014 5015 seq_printf(m, "hist_data: %p\n\n", hist_data); 5016 seq_printf(m, " n_vals: %u\n", hist_data->n_vals); 5017 seq_printf(m, " n_keys: %u\n", hist_data->n_keys); 5018 seq_printf(m, " n_fields: %u\n", hist_data->n_fields); 5019 5020 seq_puts(m, "\n val fields:\n\n"); 5021 5022 seq_puts(m, " hist_data->fields[0]:\n"); 5023 ret = hist_field_debug_show(m, hist_data->fields[0], 5024 HIST_FIELD_FL_HITCOUNT); 5025 if (ret) 5026 return; 5027 5028 for (i = 1; i < hist_data->n_vals; i++) { 5029 seq_printf(m, "\n hist_data->fields[%d]:\n", i); 5030 ret = hist_field_debug_show(m, hist_data->fields[i], 0); 5031 if (ret) 5032 return; 5033 } 5034 5035 seq_puts(m, "\n key fields:\n"); 5036 5037 for (i = hist_data->n_vals; i < hist_data->n_fields; i++) { 5038 seq_printf(m, "\n hist_data->fields[%d]:\n", i); 5039 ret = hist_field_debug_show(m, hist_data->fields[i], 5040 HIST_FIELD_FL_KEY); 5041 if (ret) 5042 return; 5043 } 5044 5045 if (hist_data->n_var_refs) 5046 seq_puts(m, "\n variable reference fields:\n"); 5047 5048 for (i = 0; i < hist_data->n_var_refs; i++) { 5049 seq_printf(m, "\n hist_data->var_refs[%d]:\n", i); 5050 ret = hist_field_debug_show(m, hist_data->var_refs[i], 5051 HIST_FIELD_FL_VAR_REF); 5052 if (ret) 5053 return; 5054 } 5055 5056 if (hist_data->n_field_vars) 5057 seq_puts(m, "\n field variables:\n"); 5058 5059 for (i = 0; i < hist_data->n_field_vars; i++) { 5060 ret = field_var_debug_show(m, hist_data->field_vars[i], i, false); 5061 if (ret) 5062 return; 5063 } 5064 5065 ret = hist_actions_debug_show(m, hist_data); 5066 if (ret) 5067 return; 5068 } 5069 5070 static int hist_debug_show(struct seq_file *m, void *v) 5071 { 5072 struct event_trigger_data *data; 5073 struct trace_event_file *event_file; 5074 int n = 0, ret = 0; 5075 5076 mutex_lock(&event_mutex); 5077 5078 event_file = event_file_data(m->private); 5079 if (unlikely(!event_file)) { 5080 ret = -ENODEV; 5081 goto out_unlock; 5082 } 5083 5084 list_for_each_entry(data, &event_file->triggers, list) { 5085 if (data->cmd_ops->trigger_type == ETT_EVENT_HIST) 5086 hist_trigger_debug_show(m, data, n++); 5087 } 5088 5089 out_unlock: 5090 mutex_unlock(&event_mutex); 5091 5092 return ret; 5093 } 5094 5095 static int event_hist_debug_open(struct inode *inode, struct file *file) 5096 { 5097 int ret; 5098 5099 ret = security_locked_down(LOCKDOWN_TRACEFS); 5100 if (ret) 5101 return ret; 5102 5103 return single_open(file, hist_debug_show, file); 5104 } 5105 5106 const struct file_operations event_hist_debug_fops = { 5107 .open = event_hist_debug_open, 5108 .read = seq_read, 5109 .llseek = seq_lseek, 5110 .release = single_release, 5111 }; 5112 #endif 5113 5114 static void hist_field_print(struct seq_file *m, struct hist_field *hist_field) 5115 { 5116 const char *field_name = hist_field_name(hist_field, 0); 5117 5118 if (hist_field->var.name) 5119 seq_printf(m, "%s=", hist_field->var.name); 5120 5121 if (hist_field->flags & HIST_FIELD_FL_CPU) 5122 seq_puts(m, "common_cpu"); 5123 else if (field_name) { 5124 if (hist_field->flags & HIST_FIELD_FL_VAR_REF || 5125 hist_field->flags & HIST_FIELD_FL_ALIAS) 5126 seq_putc(m, '$'); 5127 seq_printf(m, "%s", field_name); 5128 } else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP) 5129 seq_puts(m, "common_timestamp"); 5130 5131 if (hist_field->flags) { 5132 if (!(hist_field->flags & HIST_FIELD_FL_VAR_REF) && 5133 !(hist_field->flags & HIST_FIELD_FL_EXPR)) { 5134 const char *flags = get_hist_field_flags(hist_field); 5135 5136 if (flags) 5137 seq_printf(m, ".%s", flags); 5138 } 5139 } 5140 } 5141 5142 static int event_hist_trigger_print(struct seq_file *m, 5143 struct event_trigger_ops *ops, 5144 struct event_trigger_data *data) 5145 { 5146 struct hist_trigger_data *hist_data = data->private_data; 5147 struct hist_field *field; 5148 bool have_var = false; 5149 unsigned int i; 5150 5151 seq_puts(m, "hist:"); 5152 5153 if (data->name) 5154 seq_printf(m, "%s:", data->name); 5155 5156 seq_puts(m, "keys="); 5157 5158 for_each_hist_key_field(i, hist_data) { 5159 field = hist_data->fields[i]; 5160 5161 if (i > hist_data->n_vals) 5162 seq_puts(m, ","); 5163 5164 if (field->flags & HIST_FIELD_FL_STACKTRACE) 5165 seq_puts(m, "stacktrace"); 5166 else 5167 hist_field_print(m, field); 5168 } 5169 5170 seq_puts(m, ":vals="); 5171 5172 for_each_hist_val_field(i, hist_data) { 5173 field = hist_data->fields[i]; 5174 if (field->flags & HIST_FIELD_FL_VAR) { 5175 have_var = true; 5176 continue; 5177 } 5178 5179 if (i == HITCOUNT_IDX) 5180 seq_puts(m, "hitcount"); 5181 else { 5182 seq_puts(m, ","); 5183 hist_field_print(m, field); 5184 } 5185 } 5186 5187 if (have_var) { 5188 unsigned int n = 0; 5189 5190 seq_puts(m, ":"); 5191 5192 for_each_hist_val_field(i, hist_data) { 5193 field = hist_data->fields[i]; 5194 5195 if (field->flags & HIST_FIELD_FL_VAR) { 5196 if (n++) 5197 seq_puts(m, ","); 5198 hist_field_print(m, field); 5199 } 5200 } 5201 } 5202 5203 seq_puts(m, ":sort="); 5204 5205 for (i = 0; i < hist_data->n_sort_keys; i++) { 5206 struct tracing_map_sort_key *sort_key; 5207 unsigned int idx, first_key_idx; 5208 5209 /* skip VAR vals */ 5210 first_key_idx = hist_data->n_vals - hist_data->n_vars; 5211 5212 sort_key = &hist_data->sort_keys[i]; 5213 idx = sort_key->field_idx; 5214 5215 if (WARN_ON(idx >= HIST_FIELDS_MAX)) 5216 return -EINVAL; 5217 5218 if (i > 0) 5219 seq_puts(m, ","); 5220 5221 if (idx == HITCOUNT_IDX) 5222 seq_puts(m, "hitcount"); 5223 else { 5224 if (idx >= first_key_idx) 5225 idx += hist_data->n_vars; 5226 hist_field_print(m, hist_data->fields[idx]); 5227 } 5228 5229 if (sort_key->descending) 5230 seq_puts(m, ".descending"); 5231 } 5232 seq_printf(m, ":size=%u", (1 << hist_data->map->map_bits)); 5233 if (hist_data->enable_timestamps) 5234 seq_printf(m, ":clock=%s", hist_data->attrs->clock); 5235 5236 print_actions_spec(m, hist_data); 5237 5238 if (data->filter_str) 5239 seq_printf(m, " if %s", data->filter_str); 5240 5241 if (data->paused) 5242 seq_puts(m, " [paused]"); 5243 else 5244 seq_puts(m, " [active]"); 5245 5246 seq_putc(m, '\n'); 5247 5248 return 0; 5249 } 5250 5251 static int event_hist_trigger_init(struct event_trigger_ops *ops, 5252 struct event_trigger_data *data) 5253 { 5254 struct hist_trigger_data *hist_data = data->private_data; 5255 5256 if (!data->ref && hist_data->attrs->name) 5257 save_named_trigger(hist_data->attrs->name, data); 5258 5259 data->ref++; 5260 5261 return 0; 5262 } 5263 5264 static void unregister_field_var_hists(struct hist_trigger_data *hist_data) 5265 { 5266 struct trace_event_file *file; 5267 unsigned int i; 5268 char *cmd; 5269 int ret; 5270 5271 for (i = 0; i < hist_data->n_field_var_hists; i++) { 5272 file = hist_data->field_var_hists[i]->hist_data->event_file; 5273 cmd = hist_data->field_var_hists[i]->cmd; 5274 ret = event_hist_trigger_func(&trigger_hist_cmd, file, 5275 "!hist", "hist", cmd); 5276 WARN_ON_ONCE(ret < 0); 5277 } 5278 } 5279 5280 static void event_hist_trigger_free(struct event_trigger_ops *ops, 5281 struct event_trigger_data *data) 5282 { 5283 struct hist_trigger_data *hist_data = data->private_data; 5284 5285 if (WARN_ON_ONCE(data->ref <= 0)) 5286 return; 5287 5288 data->ref--; 5289 if (!data->ref) { 5290 if (data->name) 5291 del_named_trigger(data); 5292 5293 trigger_data_free(data); 5294 5295 remove_hist_vars(hist_data); 5296 5297 unregister_field_var_hists(hist_data); 5298 5299 destroy_hist_data(hist_data); 5300 } 5301 } 5302 5303 static struct event_trigger_ops event_hist_trigger_ops = { 5304 .func = event_hist_trigger, 5305 .print = event_hist_trigger_print, 5306 .init = event_hist_trigger_init, 5307 .free = event_hist_trigger_free, 5308 }; 5309 5310 static int event_hist_trigger_named_init(struct event_trigger_ops *ops, 5311 struct event_trigger_data *data) 5312 { 5313 data->ref++; 5314 5315 save_named_trigger(data->named_data->name, data); 5316 5317 event_hist_trigger_init(ops, data->named_data); 5318 5319 return 0; 5320 } 5321 5322 static void event_hist_trigger_named_free(struct event_trigger_ops *ops, 5323 struct event_trigger_data *data) 5324 { 5325 if (WARN_ON_ONCE(data->ref <= 0)) 5326 return; 5327 5328 event_hist_trigger_free(ops, data->named_data); 5329 5330 data->ref--; 5331 if (!data->ref) { 5332 del_named_trigger(data); 5333 trigger_data_free(data); 5334 } 5335 } 5336 5337 static struct event_trigger_ops event_hist_trigger_named_ops = { 5338 .func = event_hist_trigger, 5339 .print = event_hist_trigger_print, 5340 .init = event_hist_trigger_named_init, 5341 .free = event_hist_trigger_named_free, 5342 }; 5343 5344 static struct event_trigger_ops *event_hist_get_trigger_ops(char *cmd, 5345 char *param) 5346 { 5347 return &event_hist_trigger_ops; 5348 } 5349 5350 static void hist_clear(struct event_trigger_data *data) 5351 { 5352 struct hist_trigger_data *hist_data = data->private_data; 5353 5354 if (data->name) 5355 pause_named_trigger(data); 5356 5357 tracepoint_synchronize_unregister(); 5358 5359 tracing_map_clear(hist_data->map); 5360 5361 if (data->name) 5362 unpause_named_trigger(data); 5363 } 5364 5365 static bool compatible_field(struct ftrace_event_field *field, 5366 struct ftrace_event_field *test_field) 5367 { 5368 if (field == test_field) 5369 return true; 5370 if (field == NULL || test_field == NULL) 5371 return false; 5372 if (strcmp(field->name, test_field->name) != 0) 5373 return false; 5374 if (strcmp(field->type, test_field->type) != 0) 5375 return false; 5376 if (field->size != test_field->size) 5377 return false; 5378 if (field->is_signed != test_field->is_signed) 5379 return false; 5380 5381 return true; 5382 } 5383 5384 static bool hist_trigger_match(struct event_trigger_data *data, 5385 struct event_trigger_data *data_test, 5386 struct event_trigger_data *named_data, 5387 bool ignore_filter) 5388 { 5389 struct tracing_map_sort_key *sort_key, *sort_key_test; 5390 struct hist_trigger_data *hist_data, *hist_data_test; 5391 struct hist_field *key_field, *key_field_test; 5392 unsigned int i; 5393 5394 if (named_data && (named_data != data_test) && 5395 (named_data != data_test->named_data)) 5396 return false; 5397 5398 if (!named_data && is_named_trigger(data_test)) 5399 return false; 5400 5401 hist_data = data->private_data; 5402 hist_data_test = data_test->private_data; 5403 5404 if (hist_data->n_vals != hist_data_test->n_vals || 5405 hist_data->n_fields != hist_data_test->n_fields || 5406 hist_data->n_sort_keys != hist_data_test->n_sort_keys) 5407 return false; 5408 5409 if (!ignore_filter) { 5410 if ((data->filter_str && !data_test->filter_str) || 5411 (!data->filter_str && data_test->filter_str)) 5412 return false; 5413 } 5414 5415 for_each_hist_field(i, hist_data) { 5416 key_field = hist_data->fields[i]; 5417 key_field_test = hist_data_test->fields[i]; 5418 5419 if (key_field->flags != key_field_test->flags) 5420 return false; 5421 if (!compatible_field(key_field->field, key_field_test->field)) 5422 return false; 5423 if (key_field->offset != key_field_test->offset) 5424 return false; 5425 if (key_field->size != key_field_test->size) 5426 return false; 5427 if (key_field->is_signed != key_field_test->is_signed) 5428 return false; 5429 if (!!key_field->var.name != !!key_field_test->var.name) 5430 return false; 5431 if (key_field->var.name && 5432 strcmp(key_field->var.name, key_field_test->var.name) != 0) 5433 return false; 5434 } 5435 5436 for (i = 0; i < hist_data->n_sort_keys; i++) { 5437 sort_key = &hist_data->sort_keys[i]; 5438 sort_key_test = &hist_data_test->sort_keys[i]; 5439 5440 if (sort_key->field_idx != sort_key_test->field_idx || 5441 sort_key->descending != sort_key_test->descending) 5442 return false; 5443 } 5444 5445 if (!ignore_filter && data->filter_str && 5446 (strcmp(data->filter_str, data_test->filter_str) != 0)) 5447 return false; 5448 5449 if (!actions_match(hist_data, hist_data_test)) 5450 return false; 5451 5452 return true; 5453 } 5454 5455 static int hist_register_trigger(char *glob, struct event_trigger_ops *ops, 5456 struct event_trigger_data *data, 5457 struct trace_event_file *file) 5458 { 5459 struct hist_trigger_data *hist_data = data->private_data; 5460 struct event_trigger_data *test, *named_data = NULL; 5461 struct trace_array *tr = file->tr; 5462 int ret = 0; 5463 5464 if (hist_data->attrs->name) { 5465 named_data = find_named_trigger(hist_data->attrs->name); 5466 if (named_data) { 5467 if (!hist_trigger_match(data, named_data, named_data, 5468 true)) { 5469 hist_err(tr, HIST_ERR_NAMED_MISMATCH, errpos(hist_data->attrs->name)); 5470 ret = -EINVAL; 5471 goto out; 5472 } 5473 } 5474 } 5475 5476 if (hist_data->attrs->name && !named_data) 5477 goto new; 5478 5479 lockdep_assert_held(&event_mutex); 5480 5481 list_for_each_entry(test, &file->triggers, list) { 5482 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 5483 if (!hist_trigger_match(data, test, named_data, false)) 5484 continue; 5485 if (hist_data->attrs->pause) 5486 test->paused = true; 5487 else if (hist_data->attrs->cont) 5488 test->paused = false; 5489 else if (hist_data->attrs->clear) 5490 hist_clear(test); 5491 else { 5492 hist_err(tr, HIST_ERR_TRIGGER_EEXIST, 0); 5493 ret = -EEXIST; 5494 } 5495 goto out; 5496 } 5497 } 5498 new: 5499 if (hist_data->attrs->cont || hist_data->attrs->clear) { 5500 hist_err(tr, HIST_ERR_TRIGGER_ENOENT_CLEAR, 0); 5501 ret = -ENOENT; 5502 goto out; 5503 } 5504 5505 if (hist_data->attrs->pause) 5506 data->paused = true; 5507 5508 if (named_data) { 5509 data->private_data = named_data->private_data; 5510 set_named_trigger_data(data, named_data); 5511 data->ops = &event_hist_trigger_named_ops; 5512 } 5513 5514 if (data->ops->init) { 5515 ret = data->ops->init(data->ops, data); 5516 if (ret < 0) 5517 goto out; 5518 } 5519 5520 if (hist_data->enable_timestamps) { 5521 char *clock = hist_data->attrs->clock; 5522 5523 ret = tracing_set_clock(file->tr, hist_data->attrs->clock); 5524 if (ret) { 5525 hist_err(tr, HIST_ERR_SET_CLOCK_FAIL, errpos(clock)); 5526 goto out; 5527 } 5528 5529 tracing_set_filter_buffering(file->tr, true); 5530 } 5531 5532 if (named_data) 5533 destroy_hist_data(hist_data); 5534 5535 ret++; 5536 out: 5537 return ret; 5538 } 5539 5540 static int hist_trigger_enable(struct event_trigger_data *data, 5541 struct trace_event_file *file) 5542 { 5543 int ret = 0; 5544 5545 list_add_tail_rcu(&data->list, &file->triggers); 5546 5547 update_cond_flag(file); 5548 5549 if (trace_event_trigger_enable_disable(file, 1) < 0) { 5550 list_del_rcu(&data->list); 5551 update_cond_flag(file); 5552 ret--; 5553 } 5554 5555 return ret; 5556 } 5557 5558 static bool have_hist_trigger_match(struct event_trigger_data *data, 5559 struct trace_event_file *file) 5560 { 5561 struct hist_trigger_data *hist_data = data->private_data; 5562 struct event_trigger_data *test, *named_data = NULL; 5563 bool match = false; 5564 5565 lockdep_assert_held(&event_mutex); 5566 5567 if (hist_data->attrs->name) 5568 named_data = find_named_trigger(hist_data->attrs->name); 5569 5570 list_for_each_entry(test, &file->triggers, list) { 5571 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 5572 if (hist_trigger_match(data, test, named_data, false)) { 5573 match = true; 5574 break; 5575 } 5576 } 5577 } 5578 5579 return match; 5580 } 5581 5582 static bool hist_trigger_check_refs(struct event_trigger_data *data, 5583 struct trace_event_file *file) 5584 { 5585 struct hist_trigger_data *hist_data = data->private_data; 5586 struct event_trigger_data *test, *named_data = NULL; 5587 5588 lockdep_assert_held(&event_mutex); 5589 5590 if (hist_data->attrs->name) 5591 named_data = find_named_trigger(hist_data->attrs->name); 5592 5593 list_for_each_entry(test, &file->triggers, list) { 5594 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 5595 if (!hist_trigger_match(data, test, named_data, false)) 5596 continue; 5597 hist_data = test->private_data; 5598 if (check_var_refs(hist_data)) 5599 return true; 5600 break; 5601 } 5602 } 5603 5604 return false; 5605 } 5606 5607 static void hist_unregister_trigger(char *glob, struct event_trigger_ops *ops, 5608 struct event_trigger_data *data, 5609 struct trace_event_file *file) 5610 { 5611 struct hist_trigger_data *hist_data = data->private_data; 5612 struct event_trigger_data *test, *named_data = NULL; 5613 bool unregistered = false; 5614 5615 lockdep_assert_held(&event_mutex); 5616 5617 if (hist_data->attrs->name) 5618 named_data = find_named_trigger(hist_data->attrs->name); 5619 5620 list_for_each_entry(test, &file->triggers, list) { 5621 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 5622 if (!hist_trigger_match(data, test, named_data, false)) 5623 continue; 5624 unregistered = true; 5625 list_del_rcu(&test->list); 5626 trace_event_trigger_enable_disable(file, 0); 5627 update_cond_flag(file); 5628 break; 5629 } 5630 } 5631 5632 if (unregistered && test->ops->free) 5633 test->ops->free(test->ops, test); 5634 5635 if (hist_data->enable_timestamps) { 5636 if (!hist_data->remove || unregistered) 5637 tracing_set_filter_buffering(file->tr, false); 5638 } 5639 } 5640 5641 static bool hist_file_check_refs(struct trace_event_file *file) 5642 { 5643 struct hist_trigger_data *hist_data; 5644 struct event_trigger_data *test; 5645 5646 lockdep_assert_held(&event_mutex); 5647 5648 list_for_each_entry(test, &file->triggers, list) { 5649 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 5650 hist_data = test->private_data; 5651 if (check_var_refs(hist_data)) 5652 return true; 5653 } 5654 } 5655 5656 return false; 5657 } 5658 5659 static void hist_unreg_all(struct trace_event_file *file) 5660 { 5661 struct event_trigger_data *test, *n; 5662 struct hist_trigger_data *hist_data; 5663 struct synth_event *se; 5664 const char *se_name; 5665 5666 lockdep_assert_held(&event_mutex); 5667 5668 if (hist_file_check_refs(file)) 5669 return; 5670 5671 list_for_each_entry_safe(test, n, &file->triggers, list) { 5672 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 5673 hist_data = test->private_data; 5674 list_del_rcu(&test->list); 5675 trace_event_trigger_enable_disable(file, 0); 5676 5677 se_name = trace_event_name(file->event_call); 5678 se = find_synth_event(se_name); 5679 if (se) 5680 se->ref--; 5681 5682 update_cond_flag(file); 5683 if (hist_data->enable_timestamps) 5684 tracing_set_filter_buffering(file->tr, false); 5685 if (test->ops->free) 5686 test->ops->free(test->ops, test); 5687 } 5688 } 5689 } 5690 5691 static int event_hist_trigger_func(struct event_command *cmd_ops, 5692 struct trace_event_file *file, 5693 char *glob, char *cmd, char *param) 5694 { 5695 unsigned int hist_trigger_bits = TRACING_MAP_BITS_DEFAULT; 5696 struct event_trigger_data *trigger_data; 5697 struct hist_trigger_attrs *attrs; 5698 struct event_trigger_ops *trigger_ops; 5699 struct hist_trigger_data *hist_data; 5700 struct synth_event *se; 5701 const char *se_name; 5702 bool remove = false; 5703 char *trigger, *p; 5704 int ret = 0; 5705 5706 lockdep_assert_held(&event_mutex); 5707 5708 if (glob && strlen(glob)) { 5709 hist_err_clear(); 5710 last_cmd_set(file, param); 5711 } 5712 5713 if (!param) 5714 return -EINVAL; 5715 5716 if (glob[0] == '!') 5717 remove = true; 5718 5719 /* 5720 * separate the trigger from the filter (k:v [if filter]) 5721 * allowing for whitespace in the trigger 5722 */ 5723 p = trigger = param; 5724 do { 5725 p = strstr(p, "if"); 5726 if (!p) 5727 break; 5728 if (p == param) 5729 return -EINVAL; 5730 if (*(p - 1) != ' ' && *(p - 1) != '\t') { 5731 p++; 5732 continue; 5733 } 5734 if (p >= param + strlen(param) - (sizeof("if") - 1) - 1) 5735 return -EINVAL; 5736 if (*(p + sizeof("if") - 1) != ' ' && *(p + sizeof("if") - 1) != '\t') { 5737 p++; 5738 continue; 5739 } 5740 break; 5741 } while (p); 5742 5743 if (!p) 5744 param = NULL; 5745 else { 5746 *(p - 1) = '\0'; 5747 param = strstrip(p); 5748 trigger = strstrip(trigger); 5749 } 5750 5751 attrs = parse_hist_trigger_attrs(file->tr, trigger); 5752 if (IS_ERR(attrs)) 5753 return PTR_ERR(attrs); 5754 5755 if (attrs->map_bits) 5756 hist_trigger_bits = attrs->map_bits; 5757 5758 hist_data = create_hist_data(hist_trigger_bits, attrs, file, remove); 5759 if (IS_ERR(hist_data)) { 5760 destroy_hist_trigger_attrs(attrs); 5761 return PTR_ERR(hist_data); 5762 } 5763 5764 trigger_ops = cmd_ops->get_trigger_ops(cmd, trigger); 5765 5766 trigger_data = kzalloc(sizeof(*trigger_data), GFP_KERNEL); 5767 if (!trigger_data) { 5768 ret = -ENOMEM; 5769 goto out_free; 5770 } 5771 5772 trigger_data->count = -1; 5773 trigger_data->ops = trigger_ops; 5774 trigger_data->cmd_ops = cmd_ops; 5775 5776 INIT_LIST_HEAD(&trigger_data->list); 5777 RCU_INIT_POINTER(trigger_data->filter, NULL); 5778 5779 trigger_data->private_data = hist_data; 5780 5781 /* if param is non-empty, it's supposed to be a filter */ 5782 if (param && cmd_ops->set_filter) { 5783 ret = cmd_ops->set_filter(param, trigger_data, file); 5784 if (ret < 0) 5785 goto out_free; 5786 } 5787 5788 if (remove) { 5789 if (!have_hist_trigger_match(trigger_data, file)) 5790 goto out_free; 5791 5792 if (hist_trigger_check_refs(trigger_data, file)) { 5793 ret = -EBUSY; 5794 goto out_free; 5795 } 5796 5797 cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file); 5798 se_name = trace_event_name(file->event_call); 5799 se = find_synth_event(se_name); 5800 if (se) 5801 se->ref--; 5802 ret = 0; 5803 goto out_free; 5804 } 5805 5806 ret = cmd_ops->reg(glob, trigger_ops, trigger_data, file); 5807 /* 5808 * The above returns on success the # of triggers registered, 5809 * but if it didn't register any it returns zero. Consider no 5810 * triggers registered a failure too. 5811 */ 5812 if (!ret) { 5813 if (!(attrs->pause || attrs->cont || attrs->clear)) 5814 ret = -ENOENT; 5815 goto out_free; 5816 } else if (ret < 0) 5817 goto out_free; 5818 5819 if (get_named_trigger_data(trigger_data)) 5820 goto enable; 5821 5822 if (has_hist_vars(hist_data)) 5823 save_hist_vars(hist_data); 5824 5825 ret = create_actions(hist_data); 5826 if (ret) 5827 goto out_unreg; 5828 5829 ret = tracing_map_init(hist_data->map); 5830 if (ret) 5831 goto out_unreg; 5832 enable: 5833 ret = hist_trigger_enable(trigger_data, file); 5834 if (ret) 5835 goto out_unreg; 5836 5837 se_name = trace_event_name(file->event_call); 5838 se = find_synth_event(se_name); 5839 if (se) 5840 se->ref++; 5841 /* Just return zero, not the number of registered triggers */ 5842 ret = 0; 5843 out: 5844 if (ret == 0) 5845 hist_err_clear(); 5846 5847 return ret; 5848 out_unreg: 5849 cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file); 5850 out_free: 5851 if (cmd_ops->set_filter) 5852 cmd_ops->set_filter(NULL, trigger_data, NULL); 5853 5854 remove_hist_vars(hist_data); 5855 5856 kfree(trigger_data); 5857 5858 destroy_hist_data(hist_data); 5859 goto out; 5860 } 5861 5862 static struct event_command trigger_hist_cmd = { 5863 .name = "hist", 5864 .trigger_type = ETT_EVENT_HIST, 5865 .flags = EVENT_CMD_FL_NEEDS_REC, 5866 .func = event_hist_trigger_func, 5867 .reg = hist_register_trigger, 5868 .unreg = hist_unregister_trigger, 5869 .unreg_all = hist_unreg_all, 5870 .get_trigger_ops = event_hist_get_trigger_ops, 5871 .set_filter = set_trigger_filter, 5872 }; 5873 5874 __init int register_trigger_hist_cmd(void) 5875 { 5876 int ret; 5877 5878 ret = register_event_command(&trigger_hist_cmd); 5879 WARN_ON(ret < 0); 5880 5881 return ret; 5882 } 5883 5884 static void 5885 hist_enable_trigger(struct event_trigger_data *data, 5886 struct trace_buffer *buffer, void *rec, 5887 struct ring_buffer_event *event) 5888 { 5889 struct enable_trigger_data *enable_data = data->private_data; 5890 struct event_trigger_data *test; 5891 5892 list_for_each_entry_rcu(test, &enable_data->file->triggers, list, 5893 lockdep_is_held(&event_mutex)) { 5894 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 5895 if (enable_data->enable) 5896 test->paused = false; 5897 else 5898 test->paused = true; 5899 } 5900 } 5901 } 5902 5903 static void 5904 hist_enable_count_trigger(struct event_trigger_data *data, 5905 struct trace_buffer *buffer, void *rec, 5906 struct ring_buffer_event *event) 5907 { 5908 if (!data->count) 5909 return; 5910 5911 if (data->count != -1) 5912 (data->count)--; 5913 5914 hist_enable_trigger(data, buffer, rec, event); 5915 } 5916 5917 static struct event_trigger_ops hist_enable_trigger_ops = { 5918 .func = hist_enable_trigger, 5919 .print = event_enable_trigger_print, 5920 .init = event_trigger_init, 5921 .free = event_enable_trigger_free, 5922 }; 5923 5924 static struct event_trigger_ops hist_enable_count_trigger_ops = { 5925 .func = hist_enable_count_trigger, 5926 .print = event_enable_trigger_print, 5927 .init = event_trigger_init, 5928 .free = event_enable_trigger_free, 5929 }; 5930 5931 static struct event_trigger_ops hist_disable_trigger_ops = { 5932 .func = hist_enable_trigger, 5933 .print = event_enable_trigger_print, 5934 .init = event_trigger_init, 5935 .free = event_enable_trigger_free, 5936 }; 5937 5938 static struct event_trigger_ops hist_disable_count_trigger_ops = { 5939 .func = hist_enable_count_trigger, 5940 .print = event_enable_trigger_print, 5941 .init = event_trigger_init, 5942 .free = event_enable_trigger_free, 5943 }; 5944 5945 static struct event_trigger_ops * 5946 hist_enable_get_trigger_ops(char *cmd, char *param) 5947 { 5948 struct event_trigger_ops *ops; 5949 bool enable; 5950 5951 enable = (strcmp(cmd, ENABLE_HIST_STR) == 0); 5952 5953 if (enable) 5954 ops = param ? &hist_enable_count_trigger_ops : 5955 &hist_enable_trigger_ops; 5956 else 5957 ops = param ? &hist_disable_count_trigger_ops : 5958 &hist_disable_trigger_ops; 5959 5960 return ops; 5961 } 5962 5963 static void hist_enable_unreg_all(struct trace_event_file *file) 5964 { 5965 struct event_trigger_data *test, *n; 5966 5967 list_for_each_entry_safe(test, n, &file->triggers, list) { 5968 if (test->cmd_ops->trigger_type == ETT_HIST_ENABLE) { 5969 list_del_rcu(&test->list); 5970 update_cond_flag(file); 5971 trace_event_trigger_enable_disable(file, 0); 5972 if (test->ops->free) 5973 test->ops->free(test->ops, test); 5974 } 5975 } 5976 } 5977 5978 static struct event_command trigger_hist_enable_cmd = { 5979 .name = ENABLE_HIST_STR, 5980 .trigger_type = ETT_HIST_ENABLE, 5981 .func = event_enable_trigger_func, 5982 .reg = event_enable_register_trigger, 5983 .unreg = event_enable_unregister_trigger, 5984 .unreg_all = hist_enable_unreg_all, 5985 .get_trigger_ops = hist_enable_get_trigger_ops, 5986 .set_filter = set_trigger_filter, 5987 }; 5988 5989 static struct event_command trigger_hist_disable_cmd = { 5990 .name = DISABLE_HIST_STR, 5991 .trigger_type = ETT_HIST_ENABLE, 5992 .func = event_enable_trigger_func, 5993 .reg = event_enable_register_trigger, 5994 .unreg = event_enable_unregister_trigger, 5995 .unreg_all = hist_enable_unreg_all, 5996 .get_trigger_ops = hist_enable_get_trigger_ops, 5997 .set_filter = set_trigger_filter, 5998 }; 5999 6000 static __init void unregister_trigger_hist_enable_disable_cmds(void) 6001 { 6002 unregister_event_command(&trigger_hist_enable_cmd); 6003 unregister_event_command(&trigger_hist_disable_cmd); 6004 } 6005 6006 __init int register_trigger_hist_enable_disable_cmds(void) 6007 { 6008 int ret; 6009 6010 ret = register_event_command(&trigger_hist_enable_cmd); 6011 if (WARN_ON(ret < 0)) 6012 return ret; 6013 ret = register_event_command(&trigger_hist_disable_cmd); 6014 if (WARN_ON(ret < 0)) 6015 unregister_trigger_hist_enable_disable_cmds(); 6016 6017 return ret; 6018 } 6019