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