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