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