1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * trace_events_hist - trace event hist triggers 4 * 5 * Copyright (C) 2015 Tom Zanussi <tom.zanussi@linux.intel.com> 6 */ 7 8 #include <linux/module.h> 9 #include <linux/kallsyms.h> 10 #include <linux/security.h> 11 #include <linux/mutex.h> 12 #include <linux/slab.h> 13 #include <linux/stacktrace.h> 14 #include <linux/rculist.h> 15 #include <linux/tracefs.h> 16 17 /* for gfp flag names */ 18 #include <linux/trace_events.h> 19 #include <trace/events/mmflags.h> 20 21 #include "tracing_map.h" 22 #include "trace_synth.h" 23 24 #define ERRORS \ 25 C(NONE, "No error"), \ 26 C(DUPLICATE_VAR, "Variable already defined"), \ 27 C(VAR_NOT_UNIQUE, "Variable name not unique, need to use fully qualified name (subsys.event.var) for variable"), \ 28 C(TOO_MANY_VARS, "Too many variables defined"), \ 29 C(MALFORMED_ASSIGNMENT, "Malformed assignment"), \ 30 C(NAMED_MISMATCH, "Named hist trigger doesn't match existing named trigger (includes variables)"), \ 31 C(TRIGGER_EEXIST, "Hist trigger already exists"), \ 32 C(TRIGGER_ENOENT_CLEAR, "Can't clear or continue a nonexistent hist trigger"), \ 33 C(SET_CLOCK_FAIL, "Couldn't set trace_clock"), \ 34 C(BAD_FIELD_MODIFIER, "Invalid field modifier"), \ 35 C(TOO_MANY_SUBEXPR, "Too many subexpressions (3 max)"), \ 36 C(TIMESTAMP_MISMATCH, "Timestamp units in expression don't match"), \ 37 C(TOO_MANY_FIELD_VARS, "Too many field variables defined"), \ 38 C(EVENT_FILE_NOT_FOUND, "Event file not found"), \ 39 C(HIST_NOT_FOUND, "Matching event histogram not found"), \ 40 C(HIST_CREATE_FAIL, "Couldn't create histogram for field"), \ 41 C(SYNTH_VAR_NOT_FOUND, "Couldn't find synthetic variable"), \ 42 C(SYNTH_EVENT_NOT_FOUND,"Couldn't find synthetic event"), \ 43 C(SYNTH_TYPE_MISMATCH, "Param type doesn't match synthetic event field type"), \ 44 C(SYNTH_COUNT_MISMATCH, "Param count doesn't match synthetic event field count"), \ 45 C(FIELD_VAR_PARSE_FAIL, "Couldn't parse field variable"), \ 46 C(VAR_CREATE_FIND_FAIL, "Couldn't create or find variable"), \ 47 C(ONX_NOT_VAR, "For onmax(x) or onchange(x), x must be a variable"), \ 48 C(ONX_VAR_NOT_FOUND, "Couldn't find onmax or onchange variable"), \ 49 C(ONX_VAR_CREATE_FAIL, "Couldn't create onmax or onchange variable"), \ 50 C(FIELD_VAR_CREATE_FAIL,"Couldn't create field variable"), \ 51 C(TOO_MANY_PARAMS, "Too many action params"), \ 52 C(PARAM_NOT_FOUND, "Couldn't find param"), \ 53 C(INVALID_PARAM, "Invalid action param"), \ 54 C(ACTION_NOT_FOUND, "No action found"), \ 55 C(NO_SAVE_PARAMS, "No params found for save()"), \ 56 C(TOO_MANY_SAVE_ACTIONS,"Can't have more than one save() action per hist"), \ 57 C(ACTION_MISMATCH, "Handler doesn't support action"), \ 58 C(NO_CLOSING_PAREN, "No closing paren found"), \ 59 C(SUBSYS_NOT_FOUND, "Missing subsystem"), \ 60 C(INVALID_SUBSYS_EVENT, "Invalid subsystem or event name"), \ 61 C(INVALID_REF_KEY, "Using variable references in keys not supported"), \ 62 C(VAR_NOT_FOUND, "Couldn't find variable"), \ 63 C(FIELD_NOT_FOUND, "Couldn't find field"), \ 64 C(EMPTY_ASSIGNMENT, "Empty assignment"), \ 65 C(INVALID_SORT_MODIFIER,"Invalid sort modifier"), \ 66 C(EMPTY_SORT_FIELD, "Empty sort field"), \ 67 C(TOO_MANY_SORT_FIELDS, "Too many sort fields (Max = 2)"), \ 68 C(INVALID_SORT_FIELD, "Sort field must be a key or a val"), \ 69 C(INVALID_STR_OPERAND, "String type can not be an operand in expression"), 70 71 #undef C 72 #define C(a, b) HIST_ERR_##a 73 74 enum { ERRORS }; 75 76 #undef C 77 #define C(a, b) b 78 79 static const char *err_text[] = { ERRORS }; 80 81 struct hist_field; 82 83 typedef u64 (*hist_field_fn_t) (struct hist_field *field, 84 struct tracing_map_elt *elt, 85 struct trace_buffer *buffer, 86 struct ring_buffer_event *rbe, 87 void *event); 88 89 #define HIST_FIELD_OPERANDS_MAX 2 90 #define HIST_FIELDS_MAX (TRACING_MAP_FIELDS_MAX + TRACING_MAP_VARS_MAX) 91 #define HIST_ACTIONS_MAX 8 92 93 enum field_op_id { 94 FIELD_OP_NONE, 95 FIELD_OP_PLUS, 96 FIELD_OP_MINUS, 97 FIELD_OP_UNARY_MINUS, 98 }; 99 100 /* 101 * A hist_var (histogram variable) contains variable information for 102 * hist_fields having the HIST_FIELD_FL_VAR or HIST_FIELD_FL_VAR_REF 103 * flag set. A hist_var has a variable name e.g. ts0, and is 104 * associated with a given histogram trigger, as specified by 105 * hist_data. The hist_var idx is the unique index assigned to the 106 * variable by the hist trigger's tracing_map. The idx is what is 107 * used to set a variable's value and, by a variable reference, to 108 * retrieve it. 109 */ 110 struct hist_var { 111 char *name; 112 struct hist_trigger_data *hist_data; 113 unsigned int idx; 114 }; 115 116 struct hist_field { 117 struct ftrace_event_field *field; 118 unsigned long flags; 119 hist_field_fn_t fn; 120 unsigned int ref; 121 unsigned int size; 122 unsigned int offset; 123 unsigned int is_signed; 124 unsigned long buckets; 125 const char *type; 126 struct hist_field *operands[HIST_FIELD_OPERANDS_MAX]; 127 struct hist_trigger_data *hist_data; 128 129 /* 130 * Variable fields contain variable-specific info in var. 131 */ 132 struct hist_var var; 133 enum field_op_id operator; 134 char *system; 135 char *event_name; 136 137 /* 138 * The name field is used for EXPR and VAR_REF fields. VAR 139 * fields contain the variable name in var.name. 140 */ 141 char *name; 142 143 /* 144 * When a histogram trigger is hit, if it has any references 145 * to variables, the values of those variables are collected 146 * into a var_ref_vals array by resolve_var_refs(). The 147 * current value of each variable is read from the tracing_map 148 * using the hist field's hist_var.idx and entered into the 149 * var_ref_idx entry i.e. var_ref_vals[var_ref_idx]. 150 */ 151 unsigned int var_ref_idx; 152 bool read_once; 153 154 unsigned int var_str_idx; 155 }; 156 157 static u64 hist_field_none(struct hist_field *field, 158 struct tracing_map_elt *elt, 159 struct trace_buffer *buffer, 160 struct ring_buffer_event *rbe, 161 void *event) 162 { 163 return 0; 164 } 165 166 static u64 hist_field_counter(struct hist_field *field, 167 struct tracing_map_elt *elt, 168 struct trace_buffer *buffer, 169 struct ring_buffer_event *rbe, 170 void *event) 171 { 172 return 1; 173 } 174 175 static u64 hist_field_string(struct hist_field *hist_field, 176 struct tracing_map_elt *elt, 177 struct trace_buffer *buffer, 178 struct ring_buffer_event *rbe, 179 void *event) 180 { 181 char *addr = (char *)(event + hist_field->field->offset); 182 183 return (u64)(unsigned long)addr; 184 } 185 186 static u64 hist_field_dynstring(struct hist_field *hist_field, 187 struct tracing_map_elt *elt, 188 struct trace_buffer *buffer, 189 struct ring_buffer_event *rbe, 190 void *event) 191 { 192 u32 str_item = *(u32 *)(event + hist_field->field->offset); 193 int str_loc = str_item & 0xffff; 194 char *addr = (char *)(event + str_loc); 195 196 return (u64)(unsigned long)addr; 197 } 198 199 static u64 hist_field_pstring(struct hist_field *hist_field, 200 struct tracing_map_elt *elt, 201 struct trace_buffer *buffer, 202 struct ring_buffer_event *rbe, 203 void *event) 204 { 205 char **addr = (char **)(event + hist_field->field->offset); 206 207 return (u64)(unsigned long)*addr; 208 } 209 210 static u64 hist_field_log2(struct hist_field *hist_field, 211 struct tracing_map_elt *elt, 212 struct trace_buffer *buffer, 213 struct ring_buffer_event *rbe, 214 void *event) 215 { 216 struct hist_field *operand = hist_field->operands[0]; 217 218 u64 val = operand->fn(operand, elt, buffer, rbe, event); 219 220 return (u64) ilog2(roundup_pow_of_two(val)); 221 } 222 223 static u64 hist_field_bucket(struct hist_field *hist_field, 224 struct tracing_map_elt *elt, 225 struct trace_buffer *buffer, 226 struct ring_buffer_event *rbe, 227 void *event) 228 { 229 struct hist_field *operand = hist_field->operands[0]; 230 unsigned long buckets = hist_field->buckets; 231 232 u64 val = operand->fn(operand, elt, buffer, rbe, event); 233 234 if (WARN_ON_ONCE(!buckets)) 235 return val; 236 237 if (val >= LONG_MAX) 238 val = div64_ul(val, buckets); 239 else 240 val = (u64)((unsigned long)val / buckets); 241 return val * buckets; 242 } 243 244 static u64 hist_field_plus(struct hist_field *hist_field, 245 struct tracing_map_elt *elt, 246 struct trace_buffer *buffer, 247 struct ring_buffer_event *rbe, 248 void *event) 249 { 250 struct hist_field *operand1 = hist_field->operands[0]; 251 struct hist_field *operand2 = hist_field->operands[1]; 252 253 u64 val1 = operand1->fn(operand1, elt, buffer, rbe, event); 254 u64 val2 = operand2->fn(operand2, elt, buffer, rbe, event); 255 256 return val1 + val2; 257 } 258 259 static u64 hist_field_minus(struct hist_field *hist_field, 260 struct tracing_map_elt *elt, 261 struct trace_buffer *buffer, 262 struct ring_buffer_event *rbe, 263 void *event) 264 { 265 struct hist_field *operand1 = hist_field->operands[0]; 266 struct hist_field *operand2 = hist_field->operands[1]; 267 268 u64 val1 = operand1->fn(operand1, elt, buffer, rbe, event); 269 u64 val2 = operand2->fn(operand2, elt, buffer, rbe, event); 270 271 return val1 - val2; 272 } 273 274 static u64 hist_field_unary_minus(struct hist_field *hist_field, 275 struct tracing_map_elt *elt, 276 struct trace_buffer *buffer, 277 struct ring_buffer_event *rbe, 278 void *event) 279 { 280 struct hist_field *operand = hist_field->operands[0]; 281 282 s64 sval = (s64)operand->fn(operand, elt, buffer, rbe, event); 283 u64 val = (u64)-sval; 284 285 return val; 286 } 287 288 #define DEFINE_HIST_FIELD_FN(type) \ 289 static u64 hist_field_##type(struct hist_field *hist_field, \ 290 struct tracing_map_elt *elt, \ 291 struct trace_buffer *buffer, \ 292 struct ring_buffer_event *rbe, \ 293 void *event) \ 294 { \ 295 type *addr = (type *)(event + hist_field->field->offset); \ 296 \ 297 return (u64)(unsigned long)*addr; \ 298 } 299 300 DEFINE_HIST_FIELD_FN(s64); 301 DEFINE_HIST_FIELD_FN(u64); 302 DEFINE_HIST_FIELD_FN(s32); 303 DEFINE_HIST_FIELD_FN(u32); 304 DEFINE_HIST_FIELD_FN(s16); 305 DEFINE_HIST_FIELD_FN(u16); 306 DEFINE_HIST_FIELD_FN(s8); 307 DEFINE_HIST_FIELD_FN(u8); 308 309 #define for_each_hist_field(i, hist_data) \ 310 for ((i) = 0; (i) < (hist_data)->n_fields; (i)++) 311 312 #define for_each_hist_val_field(i, hist_data) \ 313 for ((i) = 0; (i) < (hist_data)->n_vals; (i)++) 314 315 #define for_each_hist_key_field(i, hist_data) \ 316 for ((i) = (hist_data)->n_vals; (i) < (hist_data)->n_fields; (i)++) 317 318 #define HIST_STACKTRACE_DEPTH 16 319 #define HIST_STACKTRACE_SIZE (HIST_STACKTRACE_DEPTH * sizeof(unsigned long)) 320 #define HIST_STACKTRACE_SKIP 5 321 322 #define HITCOUNT_IDX 0 323 #define HIST_KEY_SIZE_MAX (MAX_FILTER_STR_VAL + HIST_STACKTRACE_SIZE) 324 325 enum hist_field_flags { 326 HIST_FIELD_FL_HITCOUNT = 1 << 0, 327 HIST_FIELD_FL_KEY = 1 << 1, 328 HIST_FIELD_FL_STRING = 1 << 2, 329 HIST_FIELD_FL_HEX = 1 << 3, 330 HIST_FIELD_FL_SYM = 1 << 4, 331 HIST_FIELD_FL_SYM_OFFSET = 1 << 5, 332 HIST_FIELD_FL_EXECNAME = 1 << 6, 333 HIST_FIELD_FL_SYSCALL = 1 << 7, 334 HIST_FIELD_FL_STACKTRACE = 1 << 8, 335 HIST_FIELD_FL_LOG2 = 1 << 9, 336 HIST_FIELD_FL_TIMESTAMP = 1 << 10, 337 HIST_FIELD_FL_TIMESTAMP_USECS = 1 << 11, 338 HIST_FIELD_FL_VAR = 1 << 12, 339 HIST_FIELD_FL_EXPR = 1 << 13, 340 HIST_FIELD_FL_VAR_REF = 1 << 14, 341 HIST_FIELD_FL_CPU = 1 << 15, 342 HIST_FIELD_FL_ALIAS = 1 << 16, 343 HIST_FIELD_FL_BUCKET = 1 << 17, 344 }; 345 346 struct var_defs { 347 unsigned int n_vars; 348 char *name[TRACING_MAP_VARS_MAX]; 349 char *expr[TRACING_MAP_VARS_MAX]; 350 }; 351 352 struct hist_trigger_attrs { 353 char *keys_str; 354 char *vals_str; 355 char *sort_key_str; 356 char *name; 357 char *clock; 358 bool pause; 359 bool cont; 360 bool clear; 361 bool ts_in_usecs; 362 unsigned int map_bits; 363 364 char *assignment_str[TRACING_MAP_VARS_MAX]; 365 unsigned int n_assignments; 366 367 char *action_str[HIST_ACTIONS_MAX]; 368 unsigned int n_actions; 369 370 struct var_defs var_defs; 371 }; 372 373 struct field_var { 374 struct hist_field *var; 375 struct hist_field *val; 376 }; 377 378 struct field_var_hist { 379 struct hist_trigger_data *hist_data; 380 char *cmd; 381 }; 382 383 struct hist_trigger_data { 384 struct hist_field *fields[HIST_FIELDS_MAX]; 385 unsigned int n_vals; 386 unsigned int n_keys; 387 unsigned int n_fields; 388 unsigned int n_vars; 389 unsigned int n_var_str; 390 unsigned int key_size; 391 struct tracing_map_sort_key sort_keys[TRACING_MAP_SORT_KEYS_MAX]; 392 unsigned int n_sort_keys; 393 struct trace_event_file *event_file; 394 struct hist_trigger_attrs *attrs; 395 struct tracing_map *map; 396 bool enable_timestamps; 397 bool remove; 398 struct hist_field *var_refs[TRACING_MAP_VARS_MAX]; 399 unsigned int n_var_refs; 400 401 struct action_data *actions[HIST_ACTIONS_MAX]; 402 unsigned int n_actions; 403 404 struct field_var *field_vars[SYNTH_FIELDS_MAX]; 405 unsigned int n_field_vars; 406 unsigned int n_field_var_str; 407 struct field_var_hist *field_var_hists[SYNTH_FIELDS_MAX]; 408 unsigned int n_field_var_hists; 409 410 struct field_var *save_vars[SYNTH_FIELDS_MAX]; 411 unsigned int n_save_vars; 412 unsigned int n_save_var_str; 413 }; 414 415 struct action_data; 416 417 typedef void (*action_fn_t) (struct hist_trigger_data *hist_data, 418 struct tracing_map_elt *elt, 419 struct trace_buffer *buffer, void *rec, 420 struct ring_buffer_event *rbe, void *key, 421 struct action_data *data, u64 *var_ref_vals); 422 423 typedef bool (*check_track_val_fn_t) (u64 track_val, u64 var_val); 424 425 enum handler_id { 426 HANDLER_ONMATCH = 1, 427 HANDLER_ONMAX, 428 HANDLER_ONCHANGE, 429 }; 430 431 enum action_id { 432 ACTION_SAVE = 1, 433 ACTION_TRACE, 434 ACTION_SNAPSHOT, 435 }; 436 437 struct action_data { 438 enum handler_id handler; 439 enum action_id action; 440 char *action_name; 441 action_fn_t fn; 442 443 unsigned int n_params; 444 char *params[SYNTH_FIELDS_MAX]; 445 446 /* 447 * When a histogram trigger is hit, the values of any 448 * references to variables, including variables being passed 449 * as parameters to synthetic events, are collected into a 450 * var_ref_vals array. This var_ref_idx array is an array of 451 * indices into the var_ref_vals array, one for each synthetic 452 * event param, and is passed to the synthetic event 453 * invocation. 454 */ 455 unsigned int var_ref_idx[TRACING_MAP_VARS_MAX]; 456 struct synth_event *synth_event; 457 bool use_trace_keyword; 458 char *synth_event_name; 459 460 union { 461 struct { 462 char *event; 463 char *event_system; 464 } match_data; 465 466 struct { 467 /* 468 * var_str contains the $-unstripped variable 469 * name referenced by var_ref, and used when 470 * printing the action. Because var_ref 471 * creation is deferred to create_actions(), 472 * we need a per-action way to save it until 473 * then, thus var_str. 474 */ 475 char *var_str; 476 477 /* 478 * var_ref refers to the variable being 479 * tracked e.g onmax($var). 480 */ 481 struct hist_field *var_ref; 482 483 /* 484 * track_var contains the 'invisible' tracking 485 * variable created to keep the current 486 * e.g. max value. 487 */ 488 struct hist_field *track_var; 489 490 check_track_val_fn_t check_val; 491 action_fn_t save_data; 492 } track_data; 493 }; 494 }; 495 496 struct track_data { 497 u64 track_val; 498 bool updated; 499 500 unsigned int key_len; 501 void *key; 502 struct tracing_map_elt elt; 503 504 struct action_data *action_data; 505 struct hist_trigger_data *hist_data; 506 }; 507 508 struct hist_elt_data { 509 char *comm; 510 u64 *var_ref_vals; 511 char **field_var_str; 512 int n_field_var_str; 513 }; 514 515 struct snapshot_context { 516 struct tracing_map_elt *elt; 517 void *key; 518 }; 519 520 static void track_data_free(struct track_data *track_data) 521 { 522 struct hist_elt_data *elt_data; 523 524 if (!track_data) 525 return; 526 527 kfree(track_data->key); 528 529 elt_data = track_data->elt.private_data; 530 if (elt_data) { 531 kfree(elt_data->comm); 532 kfree(elt_data); 533 } 534 535 kfree(track_data); 536 } 537 538 static struct track_data *track_data_alloc(unsigned int key_len, 539 struct action_data *action_data, 540 struct hist_trigger_data *hist_data) 541 { 542 struct track_data *data = kzalloc(sizeof(*data), GFP_KERNEL); 543 struct hist_elt_data *elt_data; 544 545 if (!data) 546 return ERR_PTR(-ENOMEM); 547 548 data->key = kzalloc(key_len, GFP_KERNEL); 549 if (!data->key) { 550 track_data_free(data); 551 return ERR_PTR(-ENOMEM); 552 } 553 554 data->key_len = key_len; 555 data->action_data = action_data; 556 data->hist_data = hist_data; 557 558 elt_data = kzalloc(sizeof(*elt_data), GFP_KERNEL); 559 if (!elt_data) { 560 track_data_free(data); 561 return ERR_PTR(-ENOMEM); 562 } 563 564 data->elt.private_data = elt_data; 565 566 elt_data->comm = kzalloc(TASK_COMM_LEN, GFP_KERNEL); 567 if (!elt_data->comm) { 568 track_data_free(data); 569 return ERR_PTR(-ENOMEM); 570 } 571 572 return data; 573 } 574 575 static char last_cmd[MAX_FILTER_STR_VAL]; 576 static char last_cmd_loc[MAX_FILTER_STR_VAL]; 577 578 static int errpos(char *str) 579 { 580 return err_pos(last_cmd, str); 581 } 582 583 static void last_cmd_set(struct trace_event_file *file, char *str) 584 { 585 const char *system = NULL, *name = NULL; 586 struct trace_event_call *call; 587 588 if (!str) 589 return; 590 591 strcpy(last_cmd, "hist:"); 592 strncat(last_cmd, str, MAX_FILTER_STR_VAL - 1 - sizeof("hist:")); 593 594 if (file) { 595 call = file->event_call; 596 system = call->class->system; 597 if (system) { 598 name = trace_event_name(call); 599 if (!name) 600 system = NULL; 601 } 602 } 603 604 if (system) 605 snprintf(last_cmd_loc, MAX_FILTER_STR_VAL, "hist:%s:%s", system, name); 606 } 607 608 static void hist_err(struct trace_array *tr, u8 err_type, u8 err_pos) 609 { 610 tracing_log_err(tr, last_cmd_loc, last_cmd, err_text, 611 err_type, err_pos); 612 } 613 614 static void hist_err_clear(void) 615 { 616 last_cmd[0] = '\0'; 617 last_cmd_loc[0] = '\0'; 618 } 619 620 typedef void (*synth_probe_func_t) (void *__data, u64 *var_ref_vals, 621 unsigned int *var_ref_idx); 622 623 static inline void trace_synth(struct synth_event *event, u64 *var_ref_vals, 624 unsigned int *var_ref_idx) 625 { 626 struct tracepoint *tp = event->tp; 627 628 if (unlikely(atomic_read(&tp->key.enabled) > 0)) { 629 struct tracepoint_func *probe_func_ptr; 630 synth_probe_func_t probe_func; 631 void *__data; 632 633 if (!(cpu_online(raw_smp_processor_id()))) 634 return; 635 636 probe_func_ptr = rcu_dereference_sched((tp)->funcs); 637 if (probe_func_ptr) { 638 do { 639 probe_func = probe_func_ptr->func; 640 __data = probe_func_ptr->data; 641 probe_func(__data, var_ref_vals, var_ref_idx); 642 } while ((++probe_func_ptr)->func); 643 } 644 } 645 } 646 647 static void action_trace(struct hist_trigger_data *hist_data, 648 struct tracing_map_elt *elt, 649 struct trace_buffer *buffer, void *rec, 650 struct ring_buffer_event *rbe, void *key, 651 struct action_data *data, u64 *var_ref_vals) 652 { 653 struct synth_event *event = data->synth_event; 654 655 trace_synth(event, var_ref_vals, data->var_ref_idx); 656 } 657 658 struct hist_var_data { 659 struct list_head list; 660 struct hist_trigger_data *hist_data; 661 }; 662 663 static u64 hist_field_timestamp(struct hist_field *hist_field, 664 struct tracing_map_elt *elt, 665 struct trace_buffer *buffer, 666 struct ring_buffer_event *rbe, 667 void *event) 668 { 669 struct hist_trigger_data *hist_data = hist_field->hist_data; 670 struct trace_array *tr = hist_data->event_file->tr; 671 672 u64 ts = ring_buffer_event_time_stamp(buffer, rbe); 673 674 if (hist_data->attrs->ts_in_usecs && trace_clock_in_ns(tr)) 675 ts = ns2usecs(ts); 676 677 return ts; 678 } 679 680 static u64 hist_field_cpu(struct hist_field *hist_field, 681 struct tracing_map_elt *elt, 682 struct trace_buffer *buffer, 683 struct ring_buffer_event *rbe, 684 void *event) 685 { 686 int cpu = smp_processor_id(); 687 688 return cpu; 689 } 690 691 /** 692 * check_field_for_var_ref - Check if a VAR_REF field references a variable 693 * @hist_field: The VAR_REF field to check 694 * @var_data: The hist trigger that owns the variable 695 * @var_idx: The trigger variable identifier 696 * 697 * Check the given VAR_REF field to see whether or not it references 698 * the given variable associated with the given trigger. 699 * 700 * Return: The VAR_REF field if it does reference the variable, NULL if not 701 */ 702 static struct hist_field * 703 check_field_for_var_ref(struct hist_field *hist_field, 704 struct hist_trigger_data *var_data, 705 unsigned int var_idx) 706 { 707 WARN_ON(!(hist_field && hist_field->flags & HIST_FIELD_FL_VAR_REF)); 708 709 if (hist_field && hist_field->var.idx == var_idx && 710 hist_field->var.hist_data == var_data) 711 return hist_field; 712 713 return NULL; 714 } 715 716 /** 717 * find_var_ref - Check if a trigger has a reference to a trigger variable 718 * @hist_data: The hist trigger that might have a reference to the variable 719 * @var_data: The hist trigger that owns the variable 720 * @var_idx: The trigger variable identifier 721 * 722 * Check the list of var_refs[] on the first hist trigger to see 723 * whether any of them are references to the variable on the second 724 * trigger. 725 * 726 * Return: The VAR_REF field referencing the variable if so, NULL if not 727 */ 728 static struct hist_field *find_var_ref(struct hist_trigger_data *hist_data, 729 struct hist_trigger_data *var_data, 730 unsigned int var_idx) 731 { 732 struct hist_field *hist_field; 733 unsigned int i; 734 735 for (i = 0; i < hist_data->n_var_refs; i++) { 736 hist_field = hist_data->var_refs[i]; 737 if (check_field_for_var_ref(hist_field, var_data, var_idx)) 738 return hist_field; 739 } 740 741 return NULL; 742 } 743 744 /** 745 * find_any_var_ref - Check if there is a reference to a given trigger variable 746 * @hist_data: The hist trigger 747 * @var_idx: The trigger variable identifier 748 * 749 * Check to see whether the given variable is currently referenced by 750 * any other trigger. 751 * 752 * The trigger the variable is defined on is explicitly excluded - the 753 * assumption being that a self-reference doesn't prevent a trigger 754 * from being removed. 755 * 756 * Return: The VAR_REF field referencing the variable if so, NULL if not 757 */ 758 static struct hist_field *find_any_var_ref(struct hist_trigger_data *hist_data, 759 unsigned int var_idx) 760 { 761 struct trace_array *tr = hist_data->event_file->tr; 762 struct hist_field *found = NULL; 763 struct hist_var_data *var_data; 764 765 list_for_each_entry(var_data, &tr->hist_vars, list) { 766 if (var_data->hist_data == hist_data) 767 continue; 768 found = find_var_ref(var_data->hist_data, hist_data, var_idx); 769 if (found) 770 break; 771 } 772 773 return found; 774 } 775 776 /** 777 * check_var_refs - Check if there is a reference to any of trigger's variables 778 * @hist_data: The hist trigger 779 * 780 * A trigger can define one or more variables. If any one of them is 781 * currently referenced by any other trigger, this function will 782 * determine that. 783 784 * Typically used to determine whether or not a trigger can be removed 785 * - if there are any references to a trigger's variables, it cannot. 786 * 787 * Return: True if there is a reference to any of trigger's variables 788 */ 789 static bool check_var_refs(struct hist_trigger_data *hist_data) 790 { 791 struct hist_field *field; 792 bool found = false; 793 int i; 794 795 for_each_hist_field(i, hist_data) { 796 field = hist_data->fields[i]; 797 if (field && field->flags & HIST_FIELD_FL_VAR) { 798 if (find_any_var_ref(hist_data, field->var.idx)) { 799 found = true; 800 break; 801 } 802 } 803 } 804 805 return found; 806 } 807 808 static struct hist_var_data *find_hist_vars(struct hist_trigger_data *hist_data) 809 { 810 struct trace_array *tr = hist_data->event_file->tr; 811 struct hist_var_data *var_data, *found = NULL; 812 813 list_for_each_entry(var_data, &tr->hist_vars, list) { 814 if (var_data->hist_data == hist_data) { 815 found = var_data; 816 break; 817 } 818 } 819 820 return found; 821 } 822 823 static bool field_has_hist_vars(struct hist_field *hist_field, 824 unsigned int level) 825 { 826 int i; 827 828 if (level > 3) 829 return false; 830 831 if (!hist_field) 832 return false; 833 834 if (hist_field->flags & HIST_FIELD_FL_VAR || 835 hist_field->flags & HIST_FIELD_FL_VAR_REF) 836 return true; 837 838 for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++) { 839 struct hist_field *operand; 840 841 operand = hist_field->operands[i]; 842 if (field_has_hist_vars(operand, level + 1)) 843 return true; 844 } 845 846 return false; 847 } 848 849 static bool has_hist_vars(struct hist_trigger_data *hist_data) 850 { 851 struct hist_field *hist_field; 852 int i; 853 854 for_each_hist_field(i, hist_data) { 855 hist_field = hist_data->fields[i]; 856 if (field_has_hist_vars(hist_field, 0)) 857 return true; 858 } 859 860 return false; 861 } 862 863 static int save_hist_vars(struct hist_trigger_data *hist_data) 864 { 865 struct trace_array *tr = hist_data->event_file->tr; 866 struct hist_var_data *var_data; 867 868 var_data = find_hist_vars(hist_data); 869 if (var_data) 870 return 0; 871 872 if (tracing_check_open_get_tr(tr)) 873 return -ENODEV; 874 875 var_data = kzalloc(sizeof(*var_data), GFP_KERNEL); 876 if (!var_data) { 877 trace_array_put(tr); 878 return -ENOMEM; 879 } 880 881 var_data->hist_data = hist_data; 882 list_add(&var_data->list, &tr->hist_vars); 883 884 return 0; 885 } 886 887 static void remove_hist_vars(struct hist_trigger_data *hist_data) 888 { 889 struct trace_array *tr = hist_data->event_file->tr; 890 struct hist_var_data *var_data; 891 892 var_data = find_hist_vars(hist_data); 893 if (!var_data) 894 return; 895 896 if (WARN_ON(check_var_refs(hist_data))) 897 return; 898 899 list_del(&var_data->list); 900 901 kfree(var_data); 902 903 trace_array_put(tr); 904 } 905 906 static struct hist_field *find_var_field(struct hist_trigger_data *hist_data, 907 const char *var_name) 908 { 909 struct hist_field *hist_field, *found = NULL; 910 int i; 911 912 for_each_hist_field(i, hist_data) { 913 hist_field = hist_data->fields[i]; 914 if (hist_field && hist_field->flags & HIST_FIELD_FL_VAR && 915 strcmp(hist_field->var.name, var_name) == 0) { 916 found = hist_field; 917 break; 918 } 919 } 920 921 return found; 922 } 923 924 static struct hist_field *find_var(struct hist_trigger_data *hist_data, 925 struct trace_event_file *file, 926 const char *var_name) 927 { 928 struct hist_trigger_data *test_data; 929 struct event_trigger_data *test; 930 struct hist_field *hist_field; 931 932 lockdep_assert_held(&event_mutex); 933 934 hist_field = find_var_field(hist_data, var_name); 935 if (hist_field) 936 return hist_field; 937 938 list_for_each_entry(test, &file->triggers, list) { 939 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 940 test_data = test->private_data; 941 hist_field = find_var_field(test_data, var_name); 942 if (hist_field) 943 return hist_field; 944 } 945 } 946 947 return NULL; 948 } 949 950 static struct trace_event_file *find_var_file(struct trace_array *tr, 951 char *system, 952 char *event_name, 953 char *var_name) 954 { 955 struct hist_trigger_data *var_hist_data; 956 struct hist_var_data *var_data; 957 struct trace_event_file *file, *found = NULL; 958 959 if (system) 960 return find_event_file(tr, system, event_name); 961 962 list_for_each_entry(var_data, &tr->hist_vars, list) { 963 var_hist_data = var_data->hist_data; 964 file = var_hist_data->event_file; 965 if (file == found) 966 continue; 967 968 if (find_var_field(var_hist_data, var_name)) { 969 if (found) { 970 hist_err(tr, HIST_ERR_VAR_NOT_UNIQUE, errpos(var_name)); 971 return NULL; 972 } 973 974 found = file; 975 } 976 } 977 978 return found; 979 } 980 981 static struct hist_field *find_file_var(struct trace_event_file *file, 982 const char *var_name) 983 { 984 struct hist_trigger_data *test_data; 985 struct event_trigger_data *test; 986 struct hist_field *hist_field; 987 988 lockdep_assert_held(&event_mutex); 989 990 list_for_each_entry(test, &file->triggers, list) { 991 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 992 test_data = test->private_data; 993 hist_field = find_var_field(test_data, var_name); 994 if (hist_field) 995 return hist_field; 996 } 997 } 998 999 return NULL; 1000 } 1001 1002 static struct hist_field * 1003 find_match_var(struct hist_trigger_data *hist_data, char *var_name) 1004 { 1005 struct trace_array *tr = hist_data->event_file->tr; 1006 struct hist_field *hist_field, *found = NULL; 1007 struct trace_event_file *file; 1008 unsigned int i; 1009 1010 for (i = 0; i < hist_data->n_actions; i++) { 1011 struct action_data *data = hist_data->actions[i]; 1012 1013 if (data->handler == HANDLER_ONMATCH) { 1014 char *system = data->match_data.event_system; 1015 char *event_name = data->match_data.event; 1016 1017 file = find_var_file(tr, system, event_name, var_name); 1018 if (!file) 1019 continue; 1020 hist_field = find_file_var(file, var_name); 1021 if (hist_field) { 1022 if (found) { 1023 hist_err(tr, HIST_ERR_VAR_NOT_UNIQUE, 1024 errpos(var_name)); 1025 return ERR_PTR(-EINVAL); 1026 } 1027 1028 found = hist_field; 1029 } 1030 } 1031 } 1032 return found; 1033 } 1034 1035 static struct hist_field *find_event_var(struct hist_trigger_data *hist_data, 1036 char *system, 1037 char *event_name, 1038 char *var_name) 1039 { 1040 struct trace_array *tr = hist_data->event_file->tr; 1041 struct hist_field *hist_field = NULL; 1042 struct trace_event_file *file; 1043 1044 if (!system || !event_name) { 1045 hist_field = find_match_var(hist_data, var_name); 1046 if (IS_ERR(hist_field)) 1047 return NULL; 1048 if (hist_field) 1049 return hist_field; 1050 } 1051 1052 file = find_var_file(tr, system, event_name, var_name); 1053 if (!file) 1054 return NULL; 1055 1056 hist_field = find_file_var(file, var_name); 1057 1058 return hist_field; 1059 } 1060 1061 static u64 hist_field_var_ref(struct hist_field *hist_field, 1062 struct tracing_map_elt *elt, 1063 struct trace_buffer *buffer, 1064 struct ring_buffer_event *rbe, 1065 void *event) 1066 { 1067 struct hist_elt_data *elt_data; 1068 u64 var_val = 0; 1069 1070 if (WARN_ON_ONCE(!elt)) 1071 return var_val; 1072 1073 elt_data = elt->private_data; 1074 var_val = elt_data->var_ref_vals[hist_field->var_ref_idx]; 1075 1076 return var_val; 1077 } 1078 1079 static bool resolve_var_refs(struct hist_trigger_data *hist_data, void *key, 1080 u64 *var_ref_vals, bool self) 1081 { 1082 struct hist_trigger_data *var_data; 1083 struct tracing_map_elt *var_elt; 1084 struct hist_field *hist_field; 1085 unsigned int i, var_idx; 1086 bool resolved = true; 1087 u64 var_val = 0; 1088 1089 for (i = 0; i < hist_data->n_var_refs; i++) { 1090 hist_field = hist_data->var_refs[i]; 1091 var_idx = hist_field->var.idx; 1092 var_data = hist_field->var.hist_data; 1093 1094 if (var_data == NULL) { 1095 resolved = false; 1096 break; 1097 } 1098 1099 if ((self && var_data != hist_data) || 1100 (!self && var_data == hist_data)) 1101 continue; 1102 1103 var_elt = tracing_map_lookup(var_data->map, key); 1104 if (!var_elt) { 1105 resolved = false; 1106 break; 1107 } 1108 1109 if (!tracing_map_var_set(var_elt, var_idx)) { 1110 resolved = false; 1111 break; 1112 } 1113 1114 if (self || !hist_field->read_once) 1115 var_val = tracing_map_read_var(var_elt, var_idx); 1116 else 1117 var_val = tracing_map_read_var_once(var_elt, var_idx); 1118 1119 var_ref_vals[i] = var_val; 1120 } 1121 1122 return resolved; 1123 } 1124 1125 static const char *hist_field_name(struct hist_field *field, 1126 unsigned int level) 1127 { 1128 const char *field_name = ""; 1129 1130 if (level > 1) 1131 return field_name; 1132 1133 if (field->field) 1134 field_name = field->field->name; 1135 else if (field->flags & HIST_FIELD_FL_LOG2 || 1136 field->flags & HIST_FIELD_FL_ALIAS || 1137 field->flags & HIST_FIELD_FL_BUCKET) 1138 field_name = hist_field_name(field->operands[0], ++level); 1139 else if (field->flags & HIST_FIELD_FL_CPU) 1140 field_name = "common_cpu"; 1141 else if (field->flags & HIST_FIELD_FL_EXPR || 1142 field->flags & HIST_FIELD_FL_VAR_REF) { 1143 if (field->system) { 1144 static char full_name[MAX_FILTER_STR_VAL]; 1145 1146 strcat(full_name, field->system); 1147 strcat(full_name, "."); 1148 strcat(full_name, field->event_name); 1149 strcat(full_name, "."); 1150 strcat(full_name, field->name); 1151 field_name = full_name; 1152 } else 1153 field_name = field->name; 1154 } else if (field->flags & HIST_FIELD_FL_TIMESTAMP) 1155 field_name = "common_timestamp"; 1156 1157 if (field_name == NULL) 1158 field_name = ""; 1159 1160 return field_name; 1161 } 1162 1163 static hist_field_fn_t select_value_fn(int field_size, int field_is_signed) 1164 { 1165 hist_field_fn_t fn = NULL; 1166 1167 switch (field_size) { 1168 case 8: 1169 if (field_is_signed) 1170 fn = hist_field_s64; 1171 else 1172 fn = hist_field_u64; 1173 break; 1174 case 4: 1175 if (field_is_signed) 1176 fn = hist_field_s32; 1177 else 1178 fn = hist_field_u32; 1179 break; 1180 case 2: 1181 if (field_is_signed) 1182 fn = hist_field_s16; 1183 else 1184 fn = hist_field_u16; 1185 break; 1186 case 1: 1187 if (field_is_signed) 1188 fn = hist_field_s8; 1189 else 1190 fn = hist_field_u8; 1191 break; 1192 } 1193 1194 return fn; 1195 } 1196 1197 static int parse_map_size(char *str) 1198 { 1199 unsigned long size, map_bits; 1200 int ret; 1201 1202 ret = kstrtoul(str, 0, &size); 1203 if (ret) 1204 goto out; 1205 1206 map_bits = ilog2(roundup_pow_of_two(size)); 1207 if (map_bits < TRACING_MAP_BITS_MIN || 1208 map_bits > TRACING_MAP_BITS_MAX) 1209 ret = -EINVAL; 1210 else 1211 ret = map_bits; 1212 out: 1213 return ret; 1214 } 1215 1216 static void destroy_hist_trigger_attrs(struct hist_trigger_attrs *attrs) 1217 { 1218 unsigned int i; 1219 1220 if (!attrs) 1221 return; 1222 1223 for (i = 0; i < attrs->n_assignments; i++) 1224 kfree(attrs->assignment_str[i]); 1225 1226 for (i = 0; i < attrs->n_actions; i++) 1227 kfree(attrs->action_str[i]); 1228 1229 kfree(attrs->name); 1230 kfree(attrs->sort_key_str); 1231 kfree(attrs->keys_str); 1232 kfree(attrs->vals_str); 1233 kfree(attrs->clock); 1234 kfree(attrs); 1235 } 1236 1237 static int parse_action(char *str, struct hist_trigger_attrs *attrs) 1238 { 1239 int ret = -EINVAL; 1240 1241 if (attrs->n_actions >= HIST_ACTIONS_MAX) 1242 return ret; 1243 1244 if ((str_has_prefix(str, "onmatch(")) || 1245 (str_has_prefix(str, "onmax(")) || 1246 (str_has_prefix(str, "onchange("))) { 1247 attrs->action_str[attrs->n_actions] = kstrdup(str, GFP_KERNEL); 1248 if (!attrs->action_str[attrs->n_actions]) { 1249 ret = -ENOMEM; 1250 return ret; 1251 } 1252 attrs->n_actions++; 1253 ret = 0; 1254 } 1255 return ret; 1256 } 1257 1258 static int parse_assignment(struct trace_array *tr, 1259 char *str, struct hist_trigger_attrs *attrs) 1260 { 1261 int len, ret = 0; 1262 1263 if ((len = str_has_prefix(str, "key=")) || 1264 (len = str_has_prefix(str, "keys="))) { 1265 attrs->keys_str = kstrdup(str + len, GFP_KERNEL); 1266 if (!attrs->keys_str) { 1267 ret = -ENOMEM; 1268 goto out; 1269 } 1270 } else if ((len = str_has_prefix(str, "val=")) || 1271 (len = str_has_prefix(str, "vals=")) || 1272 (len = str_has_prefix(str, "values="))) { 1273 attrs->vals_str = kstrdup(str + len, GFP_KERNEL); 1274 if (!attrs->vals_str) { 1275 ret = -ENOMEM; 1276 goto out; 1277 } 1278 } else if ((len = str_has_prefix(str, "sort="))) { 1279 attrs->sort_key_str = kstrdup(str + len, GFP_KERNEL); 1280 if (!attrs->sort_key_str) { 1281 ret = -ENOMEM; 1282 goto out; 1283 } 1284 } else if (str_has_prefix(str, "name=")) { 1285 attrs->name = kstrdup(str, GFP_KERNEL); 1286 if (!attrs->name) { 1287 ret = -ENOMEM; 1288 goto out; 1289 } 1290 } else if ((len = str_has_prefix(str, "clock="))) { 1291 str += len; 1292 1293 str = strstrip(str); 1294 attrs->clock = kstrdup(str, GFP_KERNEL); 1295 if (!attrs->clock) { 1296 ret = -ENOMEM; 1297 goto out; 1298 } 1299 } else if ((len = str_has_prefix(str, "size="))) { 1300 int map_bits = parse_map_size(str + len); 1301 1302 if (map_bits < 0) { 1303 ret = map_bits; 1304 goto out; 1305 } 1306 attrs->map_bits = map_bits; 1307 } else { 1308 char *assignment; 1309 1310 if (attrs->n_assignments == TRACING_MAP_VARS_MAX) { 1311 hist_err(tr, HIST_ERR_TOO_MANY_VARS, errpos(str)); 1312 ret = -EINVAL; 1313 goto out; 1314 } 1315 1316 assignment = kstrdup(str, GFP_KERNEL); 1317 if (!assignment) { 1318 ret = -ENOMEM; 1319 goto out; 1320 } 1321 1322 attrs->assignment_str[attrs->n_assignments++] = assignment; 1323 } 1324 out: 1325 return ret; 1326 } 1327 1328 static struct hist_trigger_attrs * 1329 parse_hist_trigger_attrs(struct trace_array *tr, char *trigger_str) 1330 { 1331 struct hist_trigger_attrs *attrs; 1332 int ret = 0; 1333 1334 attrs = kzalloc(sizeof(*attrs), GFP_KERNEL); 1335 if (!attrs) 1336 return ERR_PTR(-ENOMEM); 1337 1338 while (trigger_str) { 1339 char *str = strsep(&trigger_str, ":"); 1340 char *rhs; 1341 1342 rhs = strchr(str, '='); 1343 if (rhs) { 1344 if (!strlen(++rhs)) { 1345 ret = -EINVAL; 1346 hist_err(tr, HIST_ERR_EMPTY_ASSIGNMENT, errpos(str)); 1347 goto free; 1348 } 1349 ret = parse_assignment(tr, str, attrs); 1350 if (ret) 1351 goto free; 1352 } else if (strcmp(str, "pause") == 0) 1353 attrs->pause = true; 1354 else if ((strcmp(str, "cont") == 0) || 1355 (strcmp(str, "continue") == 0)) 1356 attrs->cont = true; 1357 else if (strcmp(str, "clear") == 0) 1358 attrs->clear = true; 1359 else { 1360 ret = parse_action(str, attrs); 1361 if (ret) 1362 goto free; 1363 } 1364 } 1365 1366 if (!attrs->keys_str) { 1367 ret = -EINVAL; 1368 goto free; 1369 } 1370 1371 if (!attrs->clock) { 1372 attrs->clock = kstrdup("global", GFP_KERNEL); 1373 if (!attrs->clock) { 1374 ret = -ENOMEM; 1375 goto free; 1376 } 1377 } 1378 1379 return attrs; 1380 free: 1381 destroy_hist_trigger_attrs(attrs); 1382 1383 return ERR_PTR(ret); 1384 } 1385 1386 static inline void save_comm(char *comm, struct task_struct *task) 1387 { 1388 if (!task->pid) { 1389 strcpy(comm, "<idle>"); 1390 return; 1391 } 1392 1393 if (WARN_ON_ONCE(task->pid < 0)) { 1394 strcpy(comm, "<XXX>"); 1395 return; 1396 } 1397 1398 strncpy(comm, task->comm, TASK_COMM_LEN); 1399 } 1400 1401 static void hist_elt_data_free(struct hist_elt_data *elt_data) 1402 { 1403 unsigned int i; 1404 1405 for (i = 0; i < elt_data->n_field_var_str; i++) 1406 kfree(elt_data->field_var_str[i]); 1407 1408 kfree(elt_data->field_var_str); 1409 1410 kfree(elt_data->comm); 1411 kfree(elt_data); 1412 } 1413 1414 static void hist_trigger_elt_data_free(struct tracing_map_elt *elt) 1415 { 1416 struct hist_elt_data *elt_data = elt->private_data; 1417 1418 hist_elt_data_free(elt_data); 1419 } 1420 1421 static int hist_trigger_elt_data_alloc(struct tracing_map_elt *elt) 1422 { 1423 struct hist_trigger_data *hist_data = elt->map->private_data; 1424 unsigned int size = TASK_COMM_LEN; 1425 struct hist_elt_data *elt_data; 1426 struct hist_field *hist_field; 1427 unsigned int i, n_str; 1428 1429 elt_data = kzalloc(sizeof(*elt_data), GFP_KERNEL); 1430 if (!elt_data) 1431 return -ENOMEM; 1432 1433 for_each_hist_field(i, hist_data) { 1434 hist_field = hist_data->fields[i]; 1435 1436 if (hist_field->flags & HIST_FIELD_FL_EXECNAME) { 1437 elt_data->comm = kzalloc(size, GFP_KERNEL); 1438 if (!elt_data->comm) { 1439 kfree(elt_data); 1440 return -ENOMEM; 1441 } 1442 break; 1443 } 1444 } 1445 1446 n_str = hist_data->n_field_var_str + hist_data->n_save_var_str + 1447 hist_data->n_var_str; 1448 if (n_str > SYNTH_FIELDS_MAX) { 1449 hist_elt_data_free(elt_data); 1450 return -EINVAL; 1451 } 1452 1453 BUILD_BUG_ON(STR_VAR_LEN_MAX & (sizeof(u64) - 1)); 1454 1455 size = STR_VAR_LEN_MAX; 1456 1457 elt_data->field_var_str = kcalloc(n_str, sizeof(char *), GFP_KERNEL); 1458 if (!elt_data->field_var_str) { 1459 hist_elt_data_free(elt_data); 1460 return -EINVAL; 1461 } 1462 elt_data->n_field_var_str = n_str; 1463 1464 for (i = 0; i < n_str; i++) { 1465 elt_data->field_var_str[i] = kzalloc(size, GFP_KERNEL); 1466 if (!elt_data->field_var_str[i]) { 1467 hist_elt_data_free(elt_data); 1468 return -ENOMEM; 1469 } 1470 } 1471 1472 elt->private_data = elt_data; 1473 1474 return 0; 1475 } 1476 1477 static void hist_trigger_elt_data_init(struct tracing_map_elt *elt) 1478 { 1479 struct hist_elt_data *elt_data = elt->private_data; 1480 1481 if (elt_data->comm) 1482 save_comm(elt_data->comm, current); 1483 } 1484 1485 static const struct tracing_map_ops hist_trigger_elt_data_ops = { 1486 .elt_alloc = hist_trigger_elt_data_alloc, 1487 .elt_free = hist_trigger_elt_data_free, 1488 .elt_init = hist_trigger_elt_data_init, 1489 }; 1490 1491 static const char *get_hist_field_flags(struct hist_field *hist_field) 1492 { 1493 const char *flags_str = NULL; 1494 1495 if (hist_field->flags & HIST_FIELD_FL_HEX) 1496 flags_str = "hex"; 1497 else if (hist_field->flags & HIST_FIELD_FL_SYM) 1498 flags_str = "sym"; 1499 else if (hist_field->flags & HIST_FIELD_FL_SYM_OFFSET) 1500 flags_str = "sym-offset"; 1501 else if (hist_field->flags & HIST_FIELD_FL_EXECNAME) 1502 flags_str = "execname"; 1503 else if (hist_field->flags & HIST_FIELD_FL_SYSCALL) 1504 flags_str = "syscall"; 1505 else if (hist_field->flags & HIST_FIELD_FL_LOG2) 1506 flags_str = "log2"; 1507 else if (hist_field->flags & HIST_FIELD_FL_BUCKET) 1508 flags_str = "buckets"; 1509 else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP_USECS) 1510 flags_str = "usecs"; 1511 1512 return flags_str; 1513 } 1514 1515 static void expr_field_str(struct hist_field *field, char *expr) 1516 { 1517 if (field->flags & HIST_FIELD_FL_VAR_REF) 1518 strcat(expr, "$"); 1519 1520 strcat(expr, hist_field_name(field, 0)); 1521 1522 if (field->flags && !(field->flags & HIST_FIELD_FL_VAR_REF)) { 1523 const char *flags_str = get_hist_field_flags(field); 1524 1525 if (flags_str) { 1526 strcat(expr, "."); 1527 strcat(expr, flags_str); 1528 } 1529 } 1530 } 1531 1532 static char *expr_str(struct hist_field *field, unsigned int level) 1533 { 1534 char *expr; 1535 1536 if (level > 1) 1537 return NULL; 1538 1539 expr = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL); 1540 if (!expr) 1541 return NULL; 1542 1543 if (!field->operands[0]) { 1544 expr_field_str(field, expr); 1545 return expr; 1546 } 1547 1548 if (field->operator == FIELD_OP_UNARY_MINUS) { 1549 char *subexpr; 1550 1551 strcat(expr, "-("); 1552 subexpr = expr_str(field->operands[0], ++level); 1553 if (!subexpr) { 1554 kfree(expr); 1555 return NULL; 1556 } 1557 strcat(expr, subexpr); 1558 strcat(expr, ")"); 1559 1560 kfree(subexpr); 1561 1562 return expr; 1563 } 1564 1565 expr_field_str(field->operands[0], expr); 1566 1567 switch (field->operator) { 1568 case FIELD_OP_MINUS: 1569 strcat(expr, "-"); 1570 break; 1571 case FIELD_OP_PLUS: 1572 strcat(expr, "+"); 1573 break; 1574 default: 1575 kfree(expr); 1576 return NULL; 1577 } 1578 1579 expr_field_str(field->operands[1], expr); 1580 1581 return expr; 1582 } 1583 1584 static int contains_operator(char *str) 1585 { 1586 enum field_op_id field_op = FIELD_OP_NONE; 1587 char *op; 1588 1589 op = strpbrk(str, "+-"); 1590 if (!op) 1591 return FIELD_OP_NONE; 1592 1593 switch (*op) { 1594 case '-': 1595 /* 1596 * Unfortunately, the modifier ".sym-offset" 1597 * can confuse things. 1598 */ 1599 if (op - str >= 4 && !strncmp(op - 4, ".sym-offset", 11)) 1600 return FIELD_OP_NONE; 1601 1602 if (*str == '-') 1603 field_op = FIELD_OP_UNARY_MINUS; 1604 else 1605 field_op = FIELD_OP_MINUS; 1606 break; 1607 case '+': 1608 field_op = FIELD_OP_PLUS; 1609 break; 1610 default: 1611 break; 1612 } 1613 1614 return field_op; 1615 } 1616 1617 static void get_hist_field(struct hist_field *hist_field) 1618 { 1619 hist_field->ref++; 1620 } 1621 1622 static void __destroy_hist_field(struct hist_field *hist_field) 1623 { 1624 if (--hist_field->ref > 1) 1625 return; 1626 1627 kfree(hist_field->var.name); 1628 kfree(hist_field->name); 1629 1630 /* Can likely be a const */ 1631 kfree_const(hist_field->type); 1632 1633 kfree(hist_field->system); 1634 kfree(hist_field->event_name); 1635 1636 kfree(hist_field); 1637 } 1638 1639 static void destroy_hist_field(struct hist_field *hist_field, 1640 unsigned int level) 1641 { 1642 unsigned int i; 1643 1644 if (level > 3) 1645 return; 1646 1647 if (!hist_field) 1648 return; 1649 1650 if (hist_field->flags & HIST_FIELD_FL_VAR_REF) 1651 return; /* var refs will be destroyed separately */ 1652 1653 for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++) 1654 destroy_hist_field(hist_field->operands[i], level + 1); 1655 1656 __destroy_hist_field(hist_field); 1657 } 1658 1659 static struct hist_field *create_hist_field(struct hist_trigger_data *hist_data, 1660 struct ftrace_event_field *field, 1661 unsigned long flags, 1662 char *var_name) 1663 { 1664 struct hist_field *hist_field; 1665 1666 if (field && is_function_field(field)) 1667 return NULL; 1668 1669 hist_field = kzalloc(sizeof(struct hist_field), GFP_KERNEL); 1670 if (!hist_field) 1671 return NULL; 1672 1673 hist_field->ref = 1; 1674 1675 hist_field->hist_data = hist_data; 1676 1677 if (flags & HIST_FIELD_FL_EXPR || flags & HIST_FIELD_FL_ALIAS) 1678 goto out; /* caller will populate */ 1679 1680 if (flags & HIST_FIELD_FL_VAR_REF) { 1681 hist_field->fn = hist_field_var_ref; 1682 goto out; 1683 } 1684 1685 if (flags & HIST_FIELD_FL_HITCOUNT) { 1686 hist_field->fn = hist_field_counter; 1687 hist_field->size = sizeof(u64); 1688 hist_field->type = "u64"; 1689 goto out; 1690 } 1691 1692 if (flags & HIST_FIELD_FL_STACKTRACE) { 1693 hist_field->fn = hist_field_none; 1694 goto out; 1695 } 1696 1697 if (flags & (HIST_FIELD_FL_LOG2 | HIST_FIELD_FL_BUCKET)) { 1698 unsigned long fl = flags & ~(HIST_FIELD_FL_LOG2 | HIST_FIELD_FL_BUCKET); 1699 hist_field->fn = flags & HIST_FIELD_FL_LOG2 ? hist_field_log2 : 1700 hist_field_bucket; 1701 hist_field->operands[0] = create_hist_field(hist_data, field, fl, NULL); 1702 hist_field->size = hist_field->operands[0]->size; 1703 hist_field->type = kstrdup_const(hist_field->operands[0]->type, GFP_KERNEL); 1704 if (!hist_field->type) 1705 goto free; 1706 goto out; 1707 } 1708 1709 if (flags & HIST_FIELD_FL_TIMESTAMP) { 1710 hist_field->fn = hist_field_timestamp; 1711 hist_field->size = sizeof(u64); 1712 hist_field->type = "u64"; 1713 goto out; 1714 } 1715 1716 if (flags & HIST_FIELD_FL_CPU) { 1717 hist_field->fn = hist_field_cpu; 1718 hist_field->size = sizeof(int); 1719 hist_field->type = "unsigned int"; 1720 goto out; 1721 } 1722 1723 if (WARN_ON_ONCE(!field)) 1724 goto out; 1725 1726 /* Pointers to strings are just pointers and dangerous to dereference */ 1727 if (is_string_field(field) && 1728 (field->filter_type != FILTER_PTR_STRING)) { 1729 flags |= HIST_FIELD_FL_STRING; 1730 1731 hist_field->size = MAX_FILTER_STR_VAL; 1732 hist_field->type = kstrdup_const(field->type, GFP_KERNEL); 1733 if (!hist_field->type) 1734 goto free; 1735 1736 if (field->filter_type == FILTER_STATIC_STRING) 1737 hist_field->fn = hist_field_string; 1738 else if (field->filter_type == FILTER_DYN_STRING) 1739 hist_field->fn = hist_field_dynstring; 1740 else 1741 hist_field->fn = hist_field_pstring; 1742 } else { 1743 hist_field->size = field->size; 1744 hist_field->is_signed = field->is_signed; 1745 hist_field->type = kstrdup_const(field->type, GFP_KERNEL); 1746 if (!hist_field->type) 1747 goto free; 1748 1749 hist_field->fn = select_value_fn(field->size, 1750 field->is_signed); 1751 if (!hist_field->fn) { 1752 destroy_hist_field(hist_field, 0); 1753 return NULL; 1754 } 1755 } 1756 out: 1757 hist_field->field = field; 1758 hist_field->flags = flags; 1759 1760 if (var_name) { 1761 hist_field->var.name = kstrdup(var_name, GFP_KERNEL); 1762 if (!hist_field->var.name) 1763 goto free; 1764 } 1765 1766 return hist_field; 1767 free: 1768 destroy_hist_field(hist_field, 0); 1769 return NULL; 1770 } 1771 1772 static void destroy_hist_fields(struct hist_trigger_data *hist_data) 1773 { 1774 unsigned int i; 1775 1776 for (i = 0; i < HIST_FIELDS_MAX; i++) { 1777 if (hist_data->fields[i]) { 1778 destroy_hist_field(hist_data->fields[i], 0); 1779 hist_data->fields[i] = NULL; 1780 } 1781 } 1782 1783 for (i = 0; i < hist_data->n_var_refs; i++) { 1784 WARN_ON(!(hist_data->var_refs[i]->flags & HIST_FIELD_FL_VAR_REF)); 1785 __destroy_hist_field(hist_data->var_refs[i]); 1786 hist_data->var_refs[i] = NULL; 1787 } 1788 } 1789 1790 static int init_var_ref(struct hist_field *ref_field, 1791 struct hist_field *var_field, 1792 char *system, char *event_name) 1793 { 1794 int err = 0; 1795 1796 ref_field->var.idx = var_field->var.idx; 1797 ref_field->var.hist_data = var_field->hist_data; 1798 ref_field->size = var_field->size; 1799 ref_field->is_signed = var_field->is_signed; 1800 ref_field->flags |= var_field->flags & 1801 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS); 1802 1803 if (system) { 1804 ref_field->system = kstrdup(system, GFP_KERNEL); 1805 if (!ref_field->system) 1806 return -ENOMEM; 1807 } 1808 1809 if (event_name) { 1810 ref_field->event_name = kstrdup(event_name, GFP_KERNEL); 1811 if (!ref_field->event_name) { 1812 err = -ENOMEM; 1813 goto free; 1814 } 1815 } 1816 1817 if (var_field->var.name) { 1818 ref_field->name = kstrdup(var_field->var.name, GFP_KERNEL); 1819 if (!ref_field->name) { 1820 err = -ENOMEM; 1821 goto free; 1822 } 1823 } else if (var_field->name) { 1824 ref_field->name = kstrdup(var_field->name, GFP_KERNEL); 1825 if (!ref_field->name) { 1826 err = -ENOMEM; 1827 goto free; 1828 } 1829 } 1830 1831 ref_field->type = kstrdup_const(var_field->type, GFP_KERNEL); 1832 if (!ref_field->type) { 1833 err = -ENOMEM; 1834 goto free; 1835 } 1836 out: 1837 return err; 1838 free: 1839 kfree(ref_field->system); 1840 kfree(ref_field->event_name); 1841 kfree(ref_field->name); 1842 1843 goto out; 1844 } 1845 1846 static int find_var_ref_idx(struct hist_trigger_data *hist_data, 1847 struct hist_field *var_field) 1848 { 1849 struct hist_field *ref_field; 1850 int i; 1851 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 return i; 1857 } 1858 1859 return -ENOENT; 1860 } 1861 1862 /** 1863 * create_var_ref - Create a variable reference and attach it to trigger 1864 * @hist_data: The trigger that will be referencing the variable 1865 * @var_field: The VAR field to create a reference to 1866 * @system: The optional system string 1867 * @event_name: The optional event_name string 1868 * 1869 * Given a variable hist_field, create a VAR_REF hist_field that 1870 * represents a reference to it. 1871 * 1872 * This function also adds the reference to the trigger that 1873 * now references the variable. 1874 * 1875 * Return: The VAR_REF field if successful, NULL if not 1876 */ 1877 static struct hist_field *create_var_ref(struct hist_trigger_data *hist_data, 1878 struct hist_field *var_field, 1879 char *system, char *event_name) 1880 { 1881 unsigned long flags = HIST_FIELD_FL_VAR_REF; 1882 struct hist_field *ref_field; 1883 int i; 1884 1885 /* Check if the variable already exists */ 1886 for (i = 0; i < hist_data->n_var_refs; i++) { 1887 ref_field = hist_data->var_refs[i]; 1888 if (ref_field->var.idx == var_field->var.idx && 1889 ref_field->var.hist_data == var_field->hist_data) { 1890 get_hist_field(ref_field); 1891 return ref_field; 1892 } 1893 } 1894 1895 ref_field = create_hist_field(var_field->hist_data, NULL, flags, NULL); 1896 if (ref_field) { 1897 if (init_var_ref(ref_field, var_field, system, event_name)) { 1898 destroy_hist_field(ref_field, 0); 1899 return NULL; 1900 } 1901 1902 hist_data->var_refs[hist_data->n_var_refs] = ref_field; 1903 ref_field->var_ref_idx = hist_data->n_var_refs++; 1904 } 1905 1906 return ref_field; 1907 } 1908 1909 static bool is_var_ref(char *var_name) 1910 { 1911 if (!var_name || strlen(var_name) < 2 || var_name[0] != '$') 1912 return false; 1913 1914 return true; 1915 } 1916 1917 static char *field_name_from_var(struct hist_trigger_data *hist_data, 1918 char *var_name) 1919 { 1920 char *name, *field; 1921 unsigned int i; 1922 1923 for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) { 1924 name = hist_data->attrs->var_defs.name[i]; 1925 1926 if (strcmp(var_name, name) == 0) { 1927 field = hist_data->attrs->var_defs.expr[i]; 1928 if (contains_operator(field) || is_var_ref(field)) 1929 continue; 1930 return field; 1931 } 1932 } 1933 1934 return NULL; 1935 } 1936 1937 static char *local_field_var_ref(struct hist_trigger_data *hist_data, 1938 char *system, char *event_name, 1939 char *var_name) 1940 { 1941 struct trace_event_call *call; 1942 1943 if (system && event_name) { 1944 call = hist_data->event_file->event_call; 1945 1946 if (strcmp(system, call->class->system) != 0) 1947 return NULL; 1948 1949 if (strcmp(event_name, trace_event_name(call)) != 0) 1950 return NULL; 1951 } 1952 1953 if (!!system != !!event_name) 1954 return NULL; 1955 1956 if (!is_var_ref(var_name)) 1957 return NULL; 1958 1959 var_name++; 1960 1961 return field_name_from_var(hist_data, var_name); 1962 } 1963 1964 static struct hist_field *parse_var_ref(struct hist_trigger_data *hist_data, 1965 char *system, char *event_name, 1966 char *var_name) 1967 { 1968 struct hist_field *var_field = NULL, *ref_field = NULL; 1969 struct trace_array *tr = hist_data->event_file->tr; 1970 1971 if (!is_var_ref(var_name)) 1972 return NULL; 1973 1974 var_name++; 1975 1976 var_field = find_event_var(hist_data, system, event_name, var_name); 1977 if (var_field) 1978 ref_field = create_var_ref(hist_data, var_field, 1979 system, event_name); 1980 1981 if (!ref_field) 1982 hist_err(tr, HIST_ERR_VAR_NOT_FOUND, errpos(var_name)); 1983 1984 return ref_field; 1985 } 1986 1987 static struct ftrace_event_field * 1988 parse_field(struct hist_trigger_data *hist_data, struct trace_event_file *file, 1989 char *field_str, unsigned long *flags, unsigned long *buckets) 1990 { 1991 struct ftrace_event_field *field = NULL; 1992 char *field_name, *modifier, *str; 1993 struct trace_array *tr = file->tr; 1994 1995 modifier = str = kstrdup(field_str, GFP_KERNEL); 1996 if (!modifier) 1997 return ERR_PTR(-ENOMEM); 1998 1999 field_name = strsep(&modifier, "."); 2000 if (modifier) { 2001 if (strcmp(modifier, "hex") == 0) 2002 *flags |= HIST_FIELD_FL_HEX; 2003 else if (strcmp(modifier, "sym") == 0) 2004 *flags |= HIST_FIELD_FL_SYM; 2005 else if (strcmp(modifier, "sym-offset") == 0) 2006 *flags |= HIST_FIELD_FL_SYM_OFFSET; 2007 else if ((strcmp(modifier, "execname") == 0) && 2008 (strcmp(field_name, "common_pid") == 0)) 2009 *flags |= HIST_FIELD_FL_EXECNAME; 2010 else if (strcmp(modifier, "syscall") == 0) 2011 *flags |= HIST_FIELD_FL_SYSCALL; 2012 else if (strcmp(modifier, "log2") == 0) 2013 *flags |= HIST_FIELD_FL_LOG2; 2014 else if (strcmp(modifier, "usecs") == 0) 2015 *flags |= HIST_FIELD_FL_TIMESTAMP_USECS; 2016 else if (strncmp(modifier, "bucket", 6) == 0) { 2017 int ret; 2018 2019 modifier += 6; 2020 2021 if (*modifier == 's') 2022 modifier++; 2023 if (*modifier != '=') 2024 goto error; 2025 modifier++; 2026 ret = kstrtoul(modifier, 0, buckets); 2027 if (ret || !(*buckets)) 2028 goto error; 2029 *flags |= HIST_FIELD_FL_BUCKET; 2030 } else { 2031 error: 2032 hist_err(tr, HIST_ERR_BAD_FIELD_MODIFIER, errpos(modifier)); 2033 field = ERR_PTR(-EINVAL); 2034 goto out; 2035 } 2036 } 2037 2038 if (strcmp(field_name, "common_timestamp") == 0) { 2039 *flags |= HIST_FIELD_FL_TIMESTAMP; 2040 hist_data->enable_timestamps = true; 2041 if (*flags & HIST_FIELD_FL_TIMESTAMP_USECS) 2042 hist_data->attrs->ts_in_usecs = true; 2043 } else if (strcmp(field_name, "common_cpu") == 0) 2044 *flags |= HIST_FIELD_FL_CPU; 2045 else { 2046 field = trace_find_event_field(file->event_call, field_name); 2047 if (!field || !field->size) { 2048 /* 2049 * For backward compatibility, if field_name 2050 * was "cpu", then we treat this the same as 2051 * common_cpu. 2052 */ 2053 if (strcmp(field_name, "cpu") == 0) { 2054 *flags |= HIST_FIELD_FL_CPU; 2055 } else { 2056 hist_err(tr, HIST_ERR_FIELD_NOT_FOUND, 2057 errpos(field_name)); 2058 field = ERR_PTR(-EINVAL); 2059 goto out; 2060 } 2061 } 2062 } 2063 out: 2064 kfree(str); 2065 2066 return field; 2067 } 2068 2069 static struct hist_field *create_alias(struct hist_trigger_data *hist_data, 2070 struct hist_field *var_ref, 2071 char *var_name) 2072 { 2073 struct hist_field *alias = NULL; 2074 unsigned long flags = HIST_FIELD_FL_ALIAS | HIST_FIELD_FL_VAR; 2075 2076 alias = create_hist_field(hist_data, NULL, flags, var_name); 2077 if (!alias) 2078 return NULL; 2079 2080 alias->fn = var_ref->fn; 2081 alias->operands[0] = var_ref; 2082 2083 if (init_var_ref(alias, var_ref, var_ref->system, var_ref->event_name)) { 2084 destroy_hist_field(alias, 0); 2085 return NULL; 2086 } 2087 2088 alias->var_ref_idx = var_ref->var_ref_idx; 2089 2090 return alias; 2091 } 2092 2093 static struct hist_field *parse_atom(struct hist_trigger_data *hist_data, 2094 struct trace_event_file *file, char *str, 2095 unsigned long *flags, char *var_name) 2096 { 2097 char *s, *ref_system = NULL, *ref_event = NULL, *ref_var = str; 2098 struct ftrace_event_field *field = NULL; 2099 struct hist_field *hist_field = NULL; 2100 unsigned long buckets = 0; 2101 int ret = 0; 2102 2103 s = strchr(str, '.'); 2104 if (s) { 2105 s = strchr(++s, '.'); 2106 if (s) { 2107 ref_system = strsep(&str, "."); 2108 if (!str) { 2109 ret = -EINVAL; 2110 goto out; 2111 } 2112 ref_event = strsep(&str, "."); 2113 if (!str) { 2114 ret = -EINVAL; 2115 goto out; 2116 } 2117 ref_var = str; 2118 } 2119 } 2120 2121 s = local_field_var_ref(hist_data, ref_system, ref_event, ref_var); 2122 if (!s) { 2123 hist_field = parse_var_ref(hist_data, ref_system, 2124 ref_event, ref_var); 2125 if (hist_field) { 2126 if (var_name) { 2127 hist_field = create_alias(hist_data, hist_field, var_name); 2128 if (!hist_field) { 2129 ret = -ENOMEM; 2130 goto out; 2131 } 2132 } 2133 return hist_field; 2134 } 2135 } else 2136 str = s; 2137 2138 field = parse_field(hist_data, file, str, flags, &buckets); 2139 if (IS_ERR(field)) { 2140 ret = PTR_ERR(field); 2141 goto out; 2142 } 2143 2144 hist_field = create_hist_field(hist_data, field, *flags, var_name); 2145 if (!hist_field) { 2146 ret = -ENOMEM; 2147 goto out; 2148 } 2149 hist_field->buckets = buckets; 2150 2151 return hist_field; 2152 out: 2153 return ERR_PTR(ret); 2154 } 2155 2156 static struct hist_field *parse_expr(struct hist_trigger_data *hist_data, 2157 struct trace_event_file *file, 2158 char *str, unsigned long flags, 2159 char *var_name, unsigned int level); 2160 2161 static struct hist_field *parse_unary(struct hist_trigger_data *hist_data, 2162 struct trace_event_file *file, 2163 char *str, unsigned long flags, 2164 char *var_name, unsigned int level) 2165 { 2166 struct hist_field *operand1, *expr = NULL; 2167 unsigned long operand_flags; 2168 int ret = 0; 2169 char *s; 2170 2171 /* we support only -(xxx) i.e. explicit parens required */ 2172 2173 if (level > 3) { 2174 hist_err(file->tr, HIST_ERR_TOO_MANY_SUBEXPR, errpos(str)); 2175 ret = -EINVAL; 2176 goto free; 2177 } 2178 2179 str++; /* skip leading '-' */ 2180 2181 s = strchr(str, '('); 2182 if (s) 2183 str++; 2184 else { 2185 ret = -EINVAL; 2186 goto free; 2187 } 2188 2189 s = strrchr(str, ')'); 2190 if (s) 2191 *s = '\0'; 2192 else { 2193 ret = -EINVAL; /* no closing ')' */ 2194 goto free; 2195 } 2196 2197 flags |= HIST_FIELD_FL_EXPR; 2198 expr = create_hist_field(hist_data, NULL, flags, var_name); 2199 if (!expr) { 2200 ret = -ENOMEM; 2201 goto free; 2202 } 2203 2204 operand_flags = 0; 2205 operand1 = parse_expr(hist_data, file, str, operand_flags, NULL, ++level); 2206 if (IS_ERR(operand1)) { 2207 ret = PTR_ERR(operand1); 2208 goto free; 2209 } 2210 if (operand1->flags & HIST_FIELD_FL_STRING) { 2211 /* String type can not be the operand of unary operator. */ 2212 hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(str)); 2213 destroy_hist_field(operand1, 0); 2214 ret = -EINVAL; 2215 goto free; 2216 } 2217 2218 expr->flags |= operand1->flags & 2219 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS); 2220 expr->fn = hist_field_unary_minus; 2221 expr->operands[0] = operand1; 2222 expr->operator = FIELD_OP_UNARY_MINUS; 2223 expr->name = expr_str(expr, 0); 2224 expr->type = kstrdup_const(operand1->type, GFP_KERNEL); 2225 if (!expr->type) { 2226 ret = -ENOMEM; 2227 goto free; 2228 } 2229 2230 return expr; 2231 free: 2232 destroy_hist_field(expr, 0); 2233 return ERR_PTR(ret); 2234 } 2235 2236 static int check_expr_operands(struct trace_array *tr, 2237 struct hist_field *operand1, 2238 struct hist_field *operand2) 2239 { 2240 unsigned long operand1_flags = operand1->flags; 2241 unsigned long operand2_flags = operand2->flags; 2242 2243 if ((operand1_flags & HIST_FIELD_FL_VAR_REF) || 2244 (operand1_flags & HIST_FIELD_FL_ALIAS)) { 2245 struct hist_field *var; 2246 2247 var = find_var_field(operand1->var.hist_data, operand1->name); 2248 if (!var) 2249 return -EINVAL; 2250 operand1_flags = var->flags; 2251 } 2252 2253 if ((operand2_flags & HIST_FIELD_FL_VAR_REF) || 2254 (operand2_flags & HIST_FIELD_FL_ALIAS)) { 2255 struct hist_field *var; 2256 2257 var = find_var_field(operand2->var.hist_data, operand2->name); 2258 if (!var) 2259 return -EINVAL; 2260 operand2_flags = var->flags; 2261 } 2262 2263 if ((operand1_flags & HIST_FIELD_FL_TIMESTAMP_USECS) != 2264 (operand2_flags & HIST_FIELD_FL_TIMESTAMP_USECS)) { 2265 hist_err(tr, HIST_ERR_TIMESTAMP_MISMATCH, 0); 2266 return -EINVAL; 2267 } 2268 2269 return 0; 2270 } 2271 2272 static struct hist_field *parse_expr(struct hist_trigger_data *hist_data, 2273 struct trace_event_file *file, 2274 char *str, unsigned long flags, 2275 char *var_name, unsigned int level) 2276 { 2277 struct hist_field *operand1 = NULL, *operand2 = NULL, *expr = NULL; 2278 unsigned long operand_flags; 2279 int field_op, ret = -EINVAL; 2280 char *sep, *operand1_str; 2281 2282 if (level > 3) { 2283 hist_err(file->tr, HIST_ERR_TOO_MANY_SUBEXPR, errpos(str)); 2284 return ERR_PTR(-EINVAL); 2285 } 2286 2287 field_op = contains_operator(str); 2288 2289 if (field_op == FIELD_OP_NONE) 2290 return parse_atom(hist_data, file, str, &flags, var_name); 2291 2292 if (field_op == FIELD_OP_UNARY_MINUS) 2293 return parse_unary(hist_data, file, str, flags, var_name, ++level); 2294 2295 switch (field_op) { 2296 case FIELD_OP_MINUS: 2297 sep = "-"; 2298 break; 2299 case FIELD_OP_PLUS: 2300 sep = "+"; 2301 break; 2302 default: 2303 goto free; 2304 } 2305 2306 operand1_str = strsep(&str, sep); 2307 if (!operand1_str || !str) 2308 goto free; 2309 2310 operand_flags = 0; 2311 operand1 = parse_atom(hist_data, file, operand1_str, 2312 &operand_flags, NULL); 2313 if (IS_ERR(operand1)) { 2314 ret = PTR_ERR(operand1); 2315 operand1 = NULL; 2316 goto free; 2317 } 2318 if (operand1->flags & HIST_FIELD_FL_STRING) { 2319 hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(operand1_str)); 2320 ret = -EINVAL; 2321 goto free; 2322 } 2323 2324 /* rest of string could be another expression e.g. b+c in a+b+c */ 2325 operand_flags = 0; 2326 operand2 = parse_expr(hist_data, file, str, operand_flags, NULL, ++level); 2327 if (IS_ERR(operand2)) { 2328 ret = PTR_ERR(operand2); 2329 operand2 = NULL; 2330 goto free; 2331 } 2332 if (operand2->flags & HIST_FIELD_FL_STRING) { 2333 hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(str)); 2334 ret = -EINVAL; 2335 goto free; 2336 } 2337 2338 ret = check_expr_operands(file->tr, operand1, operand2); 2339 if (ret) 2340 goto free; 2341 2342 flags |= HIST_FIELD_FL_EXPR; 2343 2344 flags |= operand1->flags & 2345 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS); 2346 2347 expr = create_hist_field(hist_data, NULL, flags, var_name); 2348 if (!expr) { 2349 ret = -ENOMEM; 2350 goto free; 2351 } 2352 2353 operand1->read_once = true; 2354 operand2->read_once = true; 2355 2356 expr->operands[0] = operand1; 2357 expr->operands[1] = operand2; 2358 2359 /* The operand sizes should be the same, so just pick one */ 2360 expr->size = operand1->size; 2361 2362 expr->operator = field_op; 2363 expr->name = expr_str(expr, 0); 2364 expr->type = kstrdup_const(operand1->type, GFP_KERNEL); 2365 if (!expr->type) { 2366 ret = -ENOMEM; 2367 goto free; 2368 } 2369 2370 switch (field_op) { 2371 case FIELD_OP_MINUS: 2372 expr->fn = hist_field_minus; 2373 break; 2374 case FIELD_OP_PLUS: 2375 expr->fn = hist_field_plus; 2376 break; 2377 default: 2378 ret = -EINVAL; 2379 goto free; 2380 } 2381 2382 return expr; 2383 free: 2384 destroy_hist_field(operand1, 0); 2385 destroy_hist_field(operand2, 0); 2386 destroy_hist_field(expr, 0); 2387 2388 return ERR_PTR(ret); 2389 } 2390 2391 static char *find_trigger_filter(struct hist_trigger_data *hist_data, 2392 struct trace_event_file *file) 2393 { 2394 struct event_trigger_data *test; 2395 2396 lockdep_assert_held(&event_mutex); 2397 2398 list_for_each_entry(test, &file->triggers, list) { 2399 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 2400 if (test->private_data == hist_data) 2401 return test->filter_str; 2402 } 2403 } 2404 2405 return NULL; 2406 } 2407 2408 static struct event_command trigger_hist_cmd; 2409 static int event_hist_trigger_func(struct event_command *cmd_ops, 2410 struct trace_event_file *file, 2411 char *glob, char *cmd, char *param); 2412 2413 static bool compatible_keys(struct hist_trigger_data *target_hist_data, 2414 struct hist_trigger_data *hist_data, 2415 unsigned int n_keys) 2416 { 2417 struct hist_field *target_hist_field, *hist_field; 2418 unsigned int n, i, j; 2419 2420 if (hist_data->n_fields - hist_data->n_vals != n_keys) 2421 return false; 2422 2423 i = hist_data->n_vals; 2424 j = target_hist_data->n_vals; 2425 2426 for (n = 0; n < n_keys; n++) { 2427 hist_field = hist_data->fields[i + n]; 2428 target_hist_field = target_hist_data->fields[j + n]; 2429 2430 if (strcmp(hist_field->type, target_hist_field->type) != 0) 2431 return false; 2432 if (hist_field->size != target_hist_field->size) 2433 return false; 2434 if (hist_field->is_signed != target_hist_field->is_signed) 2435 return false; 2436 } 2437 2438 return true; 2439 } 2440 2441 static struct hist_trigger_data * 2442 find_compatible_hist(struct hist_trigger_data *target_hist_data, 2443 struct trace_event_file *file) 2444 { 2445 struct hist_trigger_data *hist_data; 2446 struct event_trigger_data *test; 2447 unsigned int n_keys; 2448 2449 lockdep_assert_held(&event_mutex); 2450 2451 n_keys = target_hist_data->n_fields - target_hist_data->n_vals; 2452 2453 list_for_each_entry(test, &file->triggers, list) { 2454 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 2455 hist_data = test->private_data; 2456 2457 if (compatible_keys(target_hist_data, hist_data, n_keys)) 2458 return hist_data; 2459 } 2460 } 2461 2462 return NULL; 2463 } 2464 2465 static struct trace_event_file *event_file(struct trace_array *tr, 2466 char *system, char *event_name) 2467 { 2468 struct trace_event_file *file; 2469 2470 file = __find_event_file(tr, system, event_name); 2471 if (!file) 2472 return ERR_PTR(-EINVAL); 2473 2474 return file; 2475 } 2476 2477 static struct hist_field * 2478 find_synthetic_field_var(struct hist_trigger_data *target_hist_data, 2479 char *system, char *event_name, char *field_name) 2480 { 2481 struct hist_field *event_var; 2482 char *synthetic_name; 2483 2484 synthetic_name = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL); 2485 if (!synthetic_name) 2486 return ERR_PTR(-ENOMEM); 2487 2488 strcpy(synthetic_name, "synthetic_"); 2489 strcat(synthetic_name, field_name); 2490 2491 event_var = find_event_var(target_hist_data, system, event_name, synthetic_name); 2492 2493 kfree(synthetic_name); 2494 2495 return event_var; 2496 } 2497 2498 /** 2499 * create_field_var_hist - Automatically create a histogram and var for a field 2500 * @target_hist_data: The target hist trigger 2501 * @subsys_name: Optional subsystem name 2502 * @event_name: Optional event name 2503 * @field_name: The name of the field (and the resulting variable) 2504 * 2505 * Hist trigger actions fetch data from variables, not directly from 2506 * events. However, for convenience, users are allowed to directly 2507 * specify an event field in an action, which will be automatically 2508 * converted into a variable on their behalf. 2509 2510 * If a user specifies a field on an event that isn't the event the 2511 * histogram currently being defined (the target event histogram), the 2512 * only way that can be accomplished is if a new hist trigger is 2513 * created and the field variable defined on that. 2514 * 2515 * This function creates a new histogram compatible with the target 2516 * event (meaning a histogram with the same key as the target 2517 * histogram), and creates a variable for the specified field, but 2518 * with 'synthetic_' prepended to the variable name in order to avoid 2519 * collision with normal field variables. 2520 * 2521 * Return: The variable created for the field. 2522 */ 2523 static struct hist_field * 2524 create_field_var_hist(struct hist_trigger_data *target_hist_data, 2525 char *subsys_name, char *event_name, char *field_name) 2526 { 2527 struct trace_array *tr = target_hist_data->event_file->tr; 2528 struct hist_trigger_data *hist_data; 2529 unsigned int i, n, first = true; 2530 struct field_var_hist *var_hist; 2531 struct trace_event_file *file; 2532 struct hist_field *key_field; 2533 struct hist_field *event_var; 2534 char *saved_filter; 2535 char *cmd; 2536 int ret; 2537 2538 if (target_hist_data->n_field_var_hists >= SYNTH_FIELDS_MAX) { 2539 hist_err(tr, HIST_ERR_TOO_MANY_FIELD_VARS, errpos(field_name)); 2540 return ERR_PTR(-EINVAL); 2541 } 2542 2543 file = event_file(tr, subsys_name, event_name); 2544 2545 if (IS_ERR(file)) { 2546 hist_err(tr, HIST_ERR_EVENT_FILE_NOT_FOUND, errpos(field_name)); 2547 ret = PTR_ERR(file); 2548 return ERR_PTR(ret); 2549 } 2550 2551 /* 2552 * Look for a histogram compatible with target. We'll use the 2553 * found histogram specification to create a new matching 2554 * histogram with our variable on it. target_hist_data is not 2555 * yet a registered histogram so we can't use that. 2556 */ 2557 hist_data = find_compatible_hist(target_hist_data, file); 2558 if (!hist_data) { 2559 hist_err(tr, HIST_ERR_HIST_NOT_FOUND, errpos(field_name)); 2560 return ERR_PTR(-EINVAL); 2561 } 2562 2563 /* See if a synthetic field variable has already been created */ 2564 event_var = find_synthetic_field_var(target_hist_data, subsys_name, 2565 event_name, field_name); 2566 if (!IS_ERR_OR_NULL(event_var)) 2567 return event_var; 2568 2569 var_hist = kzalloc(sizeof(*var_hist), GFP_KERNEL); 2570 if (!var_hist) 2571 return ERR_PTR(-ENOMEM); 2572 2573 cmd = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL); 2574 if (!cmd) { 2575 kfree(var_hist); 2576 return ERR_PTR(-ENOMEM); 2577 } 2578 2579 /* Use the same keys as the compatible histogram */ 2580 strcat(cmd, "keys="); 2581 2582 for_each_hist_key_field(i, hist_data) { 2583 key_field = hist_data->fields[i]; 2584 if (!first) 2585 strcat(cmd, ","); 2586 strcat(cmd, key_field->field->name); 2587 first = false; 2588 } 2589 2590 /* Create the synthetic field variable specification */ 2591 strcat(cmd, ":synthetic_"); 2592 strcat(cmd, field_name); 2593 strcat(cmd, "="); 2594 strcat(cmd, field_name); 2595 2596 /* Use the same filter as the compatible histogram */ 2597 saved_filter = find_trigger_filter(hist_data, file); 2598 if (saved_filter) { 2599 strcat(cmd, " if "); 2600 strcat(cmd, saved_filter); 2601 } 2602 2603 var_hist->cmd = kstrdup(cmd, GFP_KERNEL); 2604 if (!var_hist->cmd) { 2605 kfree(cmd); 2606 kfree(var_hist); 2607 return ERR_PTR(-ENOMEM); 2608 } 2609 2610 /* Save the compatible histogram information */ 2611 var_hist->hist_data = hist_data; 2612 2613 /* Create the new histogram with our variable */ 2614 ret = event_hist_trigger_func(&trigger_hist_cmd, file, 2615 "", "hist", cmd); 2616 if (ret) { 2617 kfree(cmd); 2618 kfree(var_hist->cmd); 2619 kfree(var_hist); 2620 hist_err(tr, HIST_ERR_HIST_CREATE_FAIL, errpos(field_name)); 2621 return ERR_PTR(ret); 2622 } 2623 2624 kfree(cmd); 2625 2626 /* If we can't find the variable, something went wrong */ 2627 event_var = find_synthetic_field_var(target_hist_data, subsys_name, 2628 event_name, field_name); 2629 if (IS_ERR_OR_NULL(event_var)) { 2630 kfree(var_hist->cmd); 2631 kfree(var_hist); 2632 hist_err(tr, HIST_ERR_SYNTH_VAR_NOT_FOUND, errpos(field_name)); 2633 return ERR_PTR(-EINVAL); 2634 } 2635 2636 n = target_hist_data->n_field_var_hists; 2637 target_hist_data->field_var_hists[n] = var_hist; 2638 target_hist_data->n_field_var_hists++; 2639 2640 return event_var; 2641 } 2642 2643 static struct hist_field * 2644 find_target_event_var(struct hist_trigger_data *hist_data, 2645 char *subsys_name, char *event_name, char *var_name) 2646 { 2647 struct trace_event_file *file = hist_data->event_file; 2648 struct hist_field *hist_field = NULL; 2649 2650 if (subsys_name) { 2651 struct trace_event_call *call; 2652 2653 if (!event_name) 2654 return NULL; 2655 2656 call = file->event_call; 2657 2658 if (strcmp(subsys_name, call->class->system) != 0) 2659 return NULL; 2660 2661 if (strcmp(event_name, trace_event_name(call)) != 0) 2662 return NULL; 2663 } 2664 2665 hist_field = find_var_field(hist_data, var_name); 2666 2667 return hist_field; 2668 } 2669 2670 static inline void __update_field_vars(struct tracing_map_elt *elt, 2671 struct trace_buffer *buffer, 2672 struct ring_buffer_event *rbe, 2673 void *rec, 2674 struct field_var **field_vars, 2675 unsigned int n_field_vars, 2676 unsigned int field_var_str_start) 2677 { 2678 struct hist_elt_data *elt_data = elt->private_data; 2679 unsigned int i, j, var_idx; 2680 u64 var_val; 2681 2682 for (i = 0, j = field_var_str_start; i < n_field_vars; i++) { 2683 struct field_var *field_var = field_vars[i]; 2684 struct hist_field *var = field_var->var; 2685 struct hist_field *val = field_var->val; 2686 2687 var_val = val->fn(val, elt, buffer, rbe, rec); 2688 var_idx = var->var.idx; 2689 2690 if (val->flags & HIST_FIELD_FL_STRING) { 2691 char *str = elt_data->field_var_str[j++]; 2692 char *val_str = (char *)(uintptr_t)var_val; 2693 2694 strscpy(str, val_str, STR_VAR_LEN_MAX); 2695 var_val = (u64)(uintptr_t)str; 2696 } 2697 tracing_map_set_var(elt, var_idx, var_val); 2698 } 2699 } 2700 2701 static void update_field_vars(struct hist_trigger_data *hist_data, 2702 struct tracing_map_elt *elt, 2703 struct trace_buffer *buffer, 2704 struct ring_buffer_event *rbe, 2705 void *rec) 2706 { 2707 __update_field_vars(elt, buffer, rbe, rec, hist_data->field_vars, 2708 hist_data->n_field_vars, 0); 2709 } 2710 2711 static void save_track_data_vars(struct hist_trigger_data *hist_data, 2712 struct tracing_map_elt *elt, 2713 struct trace_buffer *buffer, void *rec, 2714 struct ring_buffer_event *rbe, void *key, 2715 struct action_data *data, u64 *var_ref_vals) 2716 { 2717 __update_field_vars(elt, buffer, rbe, rec, hist_data->save_vars, 2718 hist_data->n_save_vars, hist_data->n_field_var_str); 2719 } 2720 2721 static struct hist_field *create_var(struct hist_trigger_data *hist_data, 2722 struct trace_event_file *file, 2723 char *name, int size, const char *type) 2724 { 2725 struct hist_field *var; 2726 int idx; 2727 2728 if (find_var(hist_data, file, name) && !hist_data->remove) { 2729 var = ERR_PTR(-EINVAL); 2730 goto out; 2731 } 2732 2733 var = kzalloc(sizeof(struct hist_field), GFP_KERNEL); 2734 if (!var) { 2735 var = ERR_PTR(-ENOMEM); 2736 goto out; 2737 } 2738 2739 idx = tracing_map_add_var(hist_data->map); 2740 if (idx < 0) { 2741 kfree(var); 2742 var = ERR_PTR(-EINVAL); 2743 goto out; 2744 } 2745 2746 var->ref = 1; 2747 var->flags = HIST_FIELD_FL_VAR; 2748 var->var.idx = idx; 2749 var->var.hist_data = var->hist_data = hist_data; 2750 var->size = size; 2751 var->var.name = kstrdup(name, GFP_KERNEL); 2752 var->type = kstrdup_const(type, GFP_KERNEL); 2753 if (!var->var.name || !var->type) { 2754 kfree_const(var->type); 2755 kfree(var->var.name); 2756 kfree(var); 2757 var = ERR_PTR(-ENOMEM); 2758 } 2759 out: 2760 return var; 2761 } 2762 2763 static struct field_var *create_field_var(struct hist_trigger_data *hist_data, 2764 struct trace_event_file *file, 2765 char *field_name) 2766 { 2767 struct hist_field *val = NULL, *var = NULL; 2768 unsigned long flags = HIST_FIELD_FL_VAR; 2769 struct trace_array *tr = file->tr; 2770 struct field_var *field_var; 2771 int ret = 0; 2772 2773 if (hist_data->n_field_vars >= SYNTH_FIELDS_MAX) { 2774 hist_err(tr, HIST_ERR_TOO_MANY_FIELD_VARS, errpos(field_name)); 2775 ret = -EINVAL; 2776 goto err; 2777 } 2778 2779 val = parse_atom(hist_data, file, field_name, &flags, NULL); 2780 if (IS_ERR(val)) { 2781 hist_err(tr, HIST_ERR_FIELD_VAR_PARSE_FAIL, errpos(field_name)); 2782 ret = PTR_ERR(val); 2783 goto err; 2784 } 2785 2786 var = create_var(hist_data, file, field_name, val->size, val->type); 2787 if (IS_ERR(var)) { 2788 hist_err(tr, HIST_ERR_VAR_CREATE_FIND_FAIL, errpos(field_name)); 2789 kfree(val); 2790 ret = PTR_ERR(var); 2791 goto err; 2792 } 2793 2794 field_var = kzalloc(sizeof(struct field_var), GFP_KERNEL); 2795 if (!field_var) { 2796 kfree(val); 2797 kfree(var); 2798 ret = -ENOMEM; 2799 goto err; 2800 } 2801 2802 field_var->var = var; 2803 field_var->val = val; 2804 out: 2805 return field_var; 2806 err: 2807 field_var = ERR_PTR(ret); 2808 goto out; 2809 } 2810 2811 /** 2812 * create_target_field_var - Automatically create a variable for a field 2813 * @target_hist_data: The target hist trigger 2814 * @subsys_name: Optional subsystem name 2815 * @event_name: Optional event name 2816 * @var_name: The name of the field (and the resulting variable) 2817 * 2818 * Hist trigger actions fetch data from variables, not directly from 2819 * events. However, for convenience, users are allowed to directly 2820 * specify an event field in an action, which will be automatically 2821 * converted into a variable on their behalf. 2822 2823 * This function creates a field variable with the name var_name on 2824 * the hist trigger currently being defined on the target event. If 2825 * subsys_name and event_name are specified, this function simply 2826 * verifies that they do in fact match the target event subsystem and 2827 * event name. 2828 * 2829 * Return: The variable created for the field. 2830 */ 2831 static struct field_var * 2832 create_target_field_var(struct hist_trigger_data *target_hist_data, 2833 char *subsys_name, char *event_name, char *var_name) 2834 { 2835 struct trace_event_file *file = target_hist_data->event_file; 2836 2837 if (subsys_name) { 2838 struct trace_event_call *call; 2839 2840 if (!event_name) 2841 return NULL; 2842 2843 call = file->event_call; 2844 2845 if (strcmp(subsys_name, call->class->system) != 0) 2846 return NULL; 2847 2848 if (strcmp(event_name, trace_event_name(call)) != 0) 2849 return NULL; 2850 } 2851 2852 return create_field_var(target_hist_data, file, var_name); 2853 } 2854 2855 static bool check_track_val_max(u64 track_val, u64 var_val) 2856 { 2857 if (var_val <= track_val) 2858 return false; 2859 2860 return true; 2861 } 2862 2863 static bool check_track_val_changed(u64 track_val, u64 var_val) 2864 { 2865 if (var_val == track_val) 2866 return false; 2867 2868 return true; 2869 } 2870 2871 static u64 get_track_val(struct hist_trigger_data *hist_data, 2872 struct tracing_map_elt *elt, 2873 struct action_data *data) 2874 { 2875 unsigned int track_var_idx = data->track_data.track_var->var.idx; 2876 u64 track_val; 2877 2878 track_val = tracing_map_read_var(elt, track_var_idx); 2879 2880 return track_val; 2881 } 2882 2883 static void save_track_val(struct hist_trigger_data *hist_data, 2884 struct tracing_map_elt *elt, 2885 struct action_data *data, u64 var_val) 2886 { 2887 unsigned int track_var_idx = data->track_data.track_var->var.idx; 2888 2889 tracing_map_set_var(elt, track_var_idx, var_val); 2890 } 2891 2892 static void save_track_data(struct hist_trigger_data *hist_data, 2893 struct tracing_map_elt *elt, 2894 struct trace_buffer *buffer, void *rec, 2895 struct ring_buffer_event *rbe, void *key, 2896 struct action_data *data, u64 *var_ref_vals) 2897 { 2898 if (data->track_data.save_data) 2899 data->track_data.save_data(hist_data, elt, buffer, rec, rbe, 2900 key, data, var_ref_vals); 2901 } 2902 2903 static bool check_track_val(struct tracing_map_elt *elt, 2904 struct action_data *data, 2905 u64 var_val) 2906 { 2907 struct hist_trigger_data *hist_data; 2908 u64 track_val; 2909 2910 hist_data = data->track_data.track_var->hist_data; 2911 track_val = get_track_val(hist_data, elt, data); 2912 2913 return data->track_data.check_val(track_val, var_val); 2914 } 2915 2916 #ifdef CONFIG_TRACER_SNAPSHOT 2917 static bool cond_snapshot_update(struct trace_array *tr, void *cond_data) 2918 { 2919 /* called with tr->max_lock held */ 2920 struct track_data *track_data = tr->cond_snapshot->cond_data; 2921 struct hist_elt_data *elt_data, *track_elt_data; 2922 struct snapshot_context *context = cond_data; 2923 struct action_data *action; 2924 u64 track_val; 2925 2926 if (!track_data) 2927 return false; 2928 2929 action = track_data->action_data; 2930 2931 track_val = get_track_val(track_data->hist_data, context->elt, 2932 track_data->action_data); 2933 2934 if (!action->track_data.check_val(track_data->track_val, track_val)) 2935 return false; 2936 2937 track_data->track_val = track_val; 2938 memcpy(track_data->key, context->key, track_data->key_len); 2939 2940 elt_data = context->elt->private_data; 2941 track_elt_data = track_data->elt.private_data; 2942 if (elt_data->comm) 2943 strncpy(track_elt_data->comm, elt_data->comm, TASK_COMM_LEN); 2944 2945 track_data->updated = true; 2946 2947 return true; 2948 } 2949 2950 static void save_track_data_snapshot(struct hist_trigger_data *hist_data, 2951 struct tracing_map_elt *elt, 2952 struct trace_buffer *buffer, void *rec, 2953 struct ring_buffer_event *rbe, void *key, 2954 struct action_data *data, 2955 u64 *var_ref_vals) 2956 { 2957 struct trace_event_file *file = hist_data->event_file; 2958 struct snapshot_context context; 2959 2960 context.elt = elt; 2961 context.key = key; 2962 2963 tracing_snapshot_cond(file->tr, &context); 2964 } 2965 2966 static void hist_trigger_print_key(struct seq_file *m, 2967 struct hist_trigger_data *hist_data, 2968 void *key, 2969 struct tracing_map_elt *elt); 2970 2971 static struct action_data *snapshot_action(struct hist_trigger_data *hist_data) 2972 { 2973 unsigned int i; 2974 2975 if (!hist_data->n_actions) 2976 return NULL; 2977 2978 for (i = 0; i < hist_data->n_actions; i++) { 2979 struct action_data *data = hist_data->actions[i]; 2980 2981 if (data->action == ACTION_SNAPSHOT) 2982 return data; 2983 } 2984 2985 return NULL; 2986 } 2987 2988 static void track_data_snapshot_print(struct seq_file *m, 2989 struct hist_trigger_data *hist_data) 2990 { 2991 struct trace_event_file *file = hist_data->event_file; 2992 struct track_data *track_data; 2993 struct action_data *action; 2994 2995 track_data = tracing_cond_snapshot_data(file->tr); 2996 if (!track_data) 2997 return; 2998 2999 if (!track_data->updated) 3000 return; 3001 3002 action = snapshot_action(hist_data); 3003 if (!action) 3004 return; 3005 3006 seq_puts(m, "\nSnapshot taken (see tracing/snapshot). Details:\n"); 3007 seq_printf(m, "\ttriggering value { %s(%s) }: %10llu", 3008 action->handler == HANDLER_ONMAX ? "onmax" : "onchange", 3009 action->track_data.var_str, track_data->track_val); 3010 3011 seq_puts(m, "\ttriggered by event with key: "); 3012 hist_trigger_print_key(m, hist_data, track_data->key, &track_data->elt); 3013 seq_putc(m, '\n'); 3014 } 3015 #else 3016 static bool cond_snapshot_update(struct trace_array *tr, void *cond_data) 3017 { 3018 return false; 3019 } 3020 static void save_track_data_snapshot(struct hist_trigger_data *hist_data, 3021 struct tracing_map_elt *elt, 3022 struct trace_buffer *buffer, void *rec, 3023 struct ring_buffer_event *rbe, void *key, 3024 struct action_data *data, 3025 u64 *var_ref_vals) {} 3026 static void track_data_snapshot_print(struct seq_file *m, 3027 struct hist_trigger_data *hist_data) {} 3028 #endif /* CONFIG_TRACER_SNAPSHOT */ 3029 3030 static void track_data_print(struct seq_file *m, 3031 struct hist_trigger_data *hist_data, 3032 struct tracing_map_elt *elt, 3033 struct action_data *data) 3034 { 3035 u64 track_val = get_track_val(hist_data, elt, data); 3036 unsigned int i, save_var_idx; 3037 3038 if (data->handler == HANDLER_ONMAX) 3039 seq_printf(m, "\n\tmax: %10llu", track_val); 3040 else if (data->handler == HANDLER_ONCHANGE) 3041 seq_printf(m, "\n\tchanged: %10llu", track_val); 3042 3043 if (data->action == ACTION_SNAPSHOT) 3044 return; 3045 3046 for (i = 0; i < hist_data->n_save_vars; i++) { 3047 struct hist_field *save_val = hist_data->save_vars[i]->val; 3048 struct hist_field *save_var = hist_data->save_vars[i]->var; 3049 u64 val; 3050 3051 save_var_idx = save_var->var.idx; 3052 3053 val = tracing_map_read_var(elt, save_var_idx); 3054 3055 if (save_val->flags & HIST_FIELD_FL_STRING) { 3056 seq_printf(m, " %s: %-32s", save_var->var.name, 3057 (char *)(uintptr_t)(val)); 3058 } else 3059 seq_printf(m, " %s: %10llu", save_var->var.name, val); 3060 } 3061 } 3062 3063 static void ontrack_action(struct hist_trigger_data *hist_data, 3064 struct tracing_map_elt *elt, 3065 struct trace_buffer *buffer, void *rec, 3066 struct ring_buffer_event *rbe, void *key, 3067 struct action_data *data, u64 *var_ref_vals) 3068 { 3069 u64 var_val = var_ref_vals[data->track_data.var_ref->var_ref_idx]; 3070 3071 if (check_track_val(elt, data, var_val)) { 3072 save_track_val(hist_data, elt, data, var_val); 3073 save_track_data(hist_data, elt, buffer, rec, rbe, 3074 key, data, var_ref_vals); 3075 } 3076 } 3077 3078 static void action_data_destroy(struct action_data *data) 3079 { 3080 unsigned int i; 3081 3082 lockdep_assert_held(&event_mutex); 3083 3084 kfree(data->action_name); 3085 3086 for (i = 0; i < data->n_params; i++) 3087 kfree(data->params[i]); 3088 3089 if (data->synth_event) 3090 data->synth_event->ref--; 3091 3092 kfree(data->synth_event_name); 3093 3094 kfree(data); 3095 } 3096 3097 static void track_data_destroy(struct hist_trigger_data *hist_data, 3098 struct action_data *data) 3099 { 3100 struct trace_event_file *file = hist_data->event_file; 3101 3102 destroy_hist_field(data->track_data.track_var, 0); 3103 3104 if (data->action == ACTION_SNAPSHOT) { 3105 struct track_data *track_data; 3106 3107 track_data = tracing_cond_snapshot_data(file->tr); 3108 if (track_data && track_data->hist_data == hist_data) { 3109 tracing_snapshot_cond_disable(file->tr); 3110 track_data_free(track_data); 3111 } 3112 } 3113 3114 kfree(data->track_data.var_str); 3115 3116 action_data_destroy(data); 3117 } 3118 3119 static int action_create(struct hist_trigger_data *hist_data, 3120 struct action_data *data); 3121 3122 static int track_data_create(struct hist_trigger_data *hist_data, 3123 struct action_data *data) 3124 { 3125 struct hist_field *var_field, *ref_field, *track_var = NULL; 3126 struct trace_event_file *file = hist_data->event_file; 3127 struct trace_array *tr = file->tr; 3128 char *track_data_var_str; 3129 int ret = 0; 3130 3131 track_data_var_str = data->track_data.var_str; 3132 if (track_data_var_str[0] != '$') { 3133 hist_err(tr, HIST_ERR_ONX_NOT_VAR, errpos(track_data_var_str)); 3134 return -EINVAL; 3135 } 3136 track_data_var_str++; 3137 3138 var_field = find_target_event_var(hist_data, NULL, NULL, track_data_var_str); 3139 if (!var_field) { 3140 hist_err(tr, HIST_ERR_ONX_VAR_NOT_FOUND, errpos(track_data_var_str)); 3141 return -EINVAL; 3142 } 3143 3144 ref_field = create_var_ref(hist_data, var_field, NULL, NULL); 3145 if (!ref_field) 3146 return -ENOMEM; 3147 3148 data->track_data.var_ref = ref_field; 3149 3150 if (data->handler == HANDLER_ONMAX) 3151 track_var = create_var(hist_data, file, "__max", sizeof(u64), "u64"); 3152 if (IS_ERR(track_var)) { 3153 hist_err(tr, HIST_ERR_ONX_VAR_CREATE_FAIL, 0); 3154 ret = PTR_ERR(track_var); 3155 goto out; 3156 } 3157 3158 if (data->handler == HANDLER_ONCHANGE) 3159 track_var = create_var(hist_data, file, "__change", sizeof(u64), "u64"); 3160 if (IS_ERR(track_var)) { 3161 hist_err(tr, HIST_ERR_ONX_VAR_CREATE_FAIL, 0); 3162 ret = PTR_ERR(track_var); 3163 goto out; 3164 } 3165 data->track_data.track_var = track_var; 3166 3167 ret = action_create(hist_data, data); 3168 out: 3169 return ret; 3170 } 3171 3172 static int parse_action_params(struct trace_array *tr, char *params, 3173 struct action_data *data) 3174 { 3175 char *param, *saved_param; 3176 bool first_param = true; 3177 int ret = 0; 3178 3179 while (params) { 3180 if (data->n_params >= SYNTH_FIELDS_MAX) { 3181 hist_err(tr, HIST_ERR_TOO_MANY_PARAMS, 0); 3182 goto out; 3183 } 3184 3185 param = strsep(¶ms, ","); 3186 if (!param) { 3187 hist_err(tr, HIST_ERR_PARAM_NOT_FOUND, 0); 3188 ret = -EINVAL; 3189 goto out; 3190 } 3191 3192 param = strstrip(param); 3193 if (strlen(param) < 2) { 3194 hist_err(tr, HIST_ERR_INVALID_PARAM, errpos(param)); 3195 ret = -EINVAL; 3196 goto out; 3197 } 3198 3199 saved_param = kstrdup(param, GFP_KERNEL); 3200 if (!saved_param) { 3201 ret = -ENOMEM; 3202 goto out; 3203 } 3204 3205 if (first_param && data->use_trace_keyword) { 3206 data->synth_event_name = saved_param; 3207 first_param = false; 3208 continue; 3209 } 3210 first_param = false; 3211 3212 data->params[data->n_params++] = saved_param; 3213 } 3214 out: 3215 return ret; 3216 } 3217 3218 static int action_parse(struct trace_array *tr, char *str, struct action_data *data, 3219 enum handler_id handler) 3220 { 3221 char *action_name; 3222 int ret = 0; 3223 3224 strsep(&str, "."); 3225 if (!str) { 3226 hist_err(tr, HIST_ERR_ACTION_NOT_FOUND, 0); 3227 ret = -EINVAL; 3228 goto out; 3229 } 3230 3231 action_name = strsep(&str, "("); 3232 if (!action_name || !str) { 3233 hist_err(tr, HIST_ERR_ACTION_NOT_FOUND, 0); 3234 ret = -EINVAL; 3235 goto out; 3236 } 3237 3238 if (str_has_prefix(action_name, "save")) { 3239 char *params = strsep(&str, ")"); 3240 3241 if (!params) { 3242 hist_err(tr, HIST_ERR_NO_SAVE_PARAMS, 0); 3243 ret = -EINVAL; 3244 goto out; 3245 } 3246 3247 ret = parse_action_params(tr, params, data); 3248 if (ret) 3249 goto out; 3250 3251 if (handler == HANDLER_ONMAX) 3252 data->track_data.check_val = check_track_val_max; 3253 else if (handler == HANDLER_ONCHANGE) 3254 data->track_data.check_val = check_track_val_changed; 3255 else { 3256 hist_err(tr, HIST_ERR_ACTION_MISMATCH, errpos(action_name)); 3257 ret = -EINVAL; 3258 goto out; 3259 } 3260 3261 data->track_data.save_data = save_track_data_vars; 3262 data->fn = ontrack_action; 3263 data->action = ACTION_SAVE; 3264 } else if (str_has_prefix(action_name, "snapshot")) { 3265 char *params = strsep(&str, ")"); 3266 3267 if (!str) { 3268 hist_err(tr, HIST_ERR_NO_CLOSING_PAREN, errpos(params)); 3269 ret = -EINVAL; 3270 goto out; 3271 } 3272 3273 if (handler == HANDLER_ONMAX) 3274 data->track_data.check_val = check_track_val_max; 3275 else if (handler == HANDLER_ONCHANGE) 3276 data->track_data.check_val = check_track_val_changed; 3277 else { 3278 hist_err(tr, HIST_ERR_ACTION_MISMATCH, errpos(action_name)); 3279 ret = -EINVAL; 3280 goto out; 3281 } 3282 3283 data->track_data.save_data = save_track_data_snapshot; 3284 data->fn = ontrack_action; 3285 data->action = ACTION_SNAPSHOT; 3286 } else { 3287 char *params = strsep(&str, ")"); 3288 3289 if (str_has_prefix(action_name, "trace")) 3290 data->use_trace_keyword = true; 3291 3292 if (params) { 3293 ret = parse_action_params(tr, params, data); 3294 if (ret) 3295 goto out; 3296 } 3297 3298 if (handler == HANDLER_ONMAX) 3299 data->track_data.check_val = check_track_val_max; 3300 else if (handler == HANDLER_ONCHANGE) 3301 data->track_data.check_val = check_track_val_changed; 3302 3303 if (handler != HANDLER_ONMATCH) { 3304 data->track_data.save_data = action_trace; 3305 data->fn = ontrack_action; 3306 } else 3307 data->fn = action_trace; 3308 3309 data->action = ACTION_TRACE; 3310 } 3311 3312 data->action_name = kstrdup(action_name, GFP_KERNEL); 3313 if (!data->action_name) { 3314 ret = -ENOMEM; 3315 goto out; 3316 } 3317 3318 data->handler = handler; 3319 out: 3320 return ret; 3321 } 3322 3323 static struct action_data *track_data_parse(struct hist_trigger_data *hist_data, 3324 char *str, enum handler_id handler) 3325 { 3326 struct action_data *data; 3327 int ret = -EINVAL; 3328 char *var_str; 3329 3330 data = kzalloc(sizeof(*data), GFP_KERNEL); 3331 if (!data) 3332 return ERR_PTR(-ENOMEM); 3333 3334 var_str = strsep(&str, ")"); 3335 if (!var_str || !str) { 3336 ret = -EINVAL; 3337 goto free; 3338 } 3339 3340 data->track_data.var_str = kstrdup(var_str, GFP_KERNEL); 3341 if (!data->track_data.var_str) { 3342 ret = -ENOMEM; 3343 goto free; 3344 } 3345 3346 ret = action_parse(hist_data->event_file->tr, str, data, handler); 3347 if (ret) 3348 goto free; 3349 out: 3350 return data; 3351 free: 3352 track_data_destroy(hist_data, data); 3353 data = ERR_PTR(ret); 3354 goto out; 3355 } 3356 3357 static void onmatch_destroy(struct action_data *data) 3358 { 3359 kfree(data->match_data.event); 3360 kfree(data->match_data.event_system); 3361 3362 action_data_destroy(data); 3363 } 3364 3365 static void destroy_field_var(struct field_var *field_var) 3366 { 3367 if (!field_var) 3368 return; 3369 3370 destroy_hist_field(field_var->var, 0); 3371 destroy_hist_field(field_var->val, 0); 3372 3373 kfree(field_var); 3374 } 3375 3376 static void destroy_field_vars(struct hist_trigger_data *hist_data) 3377 { 3378 unsigned int i; 3379 3380 for (i = 0; i < hist_data->n_field_vars; i++) 3381 destroy_field_var(hist_data->field_vars[i]); 3382 3383 for (i = 0; i < hist_data->n_save_vars; i++) 3384 destroy_field_var(hist_data->save_vars[i]); 3385 } 3386 3387 static void save_field_var(struct hist_trigger_data *hist_data, 3388 struct field_var *field_var) 3389 { 3390 hist_data->field_vars[hist_data->n_field_vars++] = field_var; 3391 3392 if (field_var->val->flags & HIST_FIELD_FL_STRING) 3393 hist_data->n_field_var_str++; 3394 } 3395 3396 3397 static int check_synth_field(struct synth_event *event, 3398 struct hist_field *hist_field, 3399 unsigned int field_pos) 3400 { 3401 struct synth_field *field; 3402 3403 if (field_pos >= event->n_fields) 3404 return -EINVAL; 3405 3406 field = event->fields[field_pos]; 3407 3408 /* 3409 * A dynamic string synth field can accept static or 3410 * dynamic. A static string synth field can only accept a 3411 * same-sized static string, which is checked for later. 3412 */ 3413 if (strstr(hist_field->type, "char[") && field->is_string 3414 && field->is_dynamic) 3415 return 0; 3416 3417 if (strcmp(field->type, hist_field->type) != 0) { 3418 if (field->size != hist_field->size || 3419 field->is_signed != hist_field->is_signed) 3420 return -EINVAL; 3421 } 3422 3423 return 0; 3424 } 3425 3426 static struct hist_field * 3427 trace_action_find_var(struct hist_trigger_data *hist_data, 3428 struct action_data *data, 3429 char *system, char *event, char *var) 3430 { 3431 struct trace_array *tr = hist_data->event_file->tr; 3432 struct hist_field *hist_field; 3433 3434 var++; /* skip '$' */ 3435 3436 hist_field = find_target_event_var(hist_data, system, event, var); 3437 if (!hist_field) { 3438 if (!system && data->handler == HANDLER_ONMATCH) { 3439 system = data->match_data.event_system; 3440 event = data->match_data.event; 3441 } 3442 3443 hist_field = find_event_var(hist_data, system, event, var); 3444 } 3445 3446 if (!hist_field) 3447 hist_err(tr, HIST_ERR_PARAM_NOT_FOUND, errpos(var)); 3448 3449 return hist_field; 3450 } 3451 3452 static struct hist_field * 3453 trace_action_create_field_var(struct hist_trigger_data *hist_data, 3454 struct action_data *data, char *system, 3455 char *event, char *var) 3456 { 3457 struct hist_field *hist_field = NULL; 3458 struct field_var *field_var; 3459 3460 /* 3461 * First try to create a field var on the target event (the 3462 * currently being defined). This will create a variable for 3463 * unqualified fields on the target event, or if qualified, 3464 * target fields that have qualified names matching the target. 3465 */ 3466 field_var = create_target_field_var(hist_data, system, event, var); 3467 3468 if (field_var && !IS_ERR(field_var)) { 3469 save_field_var(hist_data, field_var); 3470 hist_field = field_var->var; 3471 } else { 3472 field_var = NULL; 3473 /* 3474 * If no explicit system.event is specified, default to 3475 * looking for fields on the onmatch(system.event.xxx) 3476 * event. 3477 */ 3478 if (!system && data->handler == HANDLER_ONMATCH) { 3479 system = data->match_data.event_system; 3480 event = data->match_data.event; 3481 } 3482 3483 if (!event) 3484 goto free; 3485 /* 3486 * At this point, we're looking at a field on another 3487 * event. Because we can't modify a hist trigger on 3488 * another event to add a variable for a field, we need 3489 * to create a new trigger on that event and create the 3490 * variable at the same time. 3491 */ 3492 hist_field = create_field_var_hist(hist_data, system, event, var); 3493 if (IS_ERR(hist_field)) 3494 goto free; 3495 } 3496 out: 3497 return hist_field; 3498 free: 3499 destroy_field_var(field_var); 3500 hist_field = NULL; 3501 goto out; 3502 } 3503 3504 static int trace_action_create(struct hist_trigger_data *hist_data, 3505 struct action_data *data) 3506 { 3507 struct trace_array *tr = hist_data->event_file->tr; 3508 char *event_name, *param, *system = NULL; 3509 struct hist_field *hist_field, *var_ref; 3510 unsigned int i; 3511 unsigned int field_pos = 0; 3512 struct synth_event *event; 3513 char *synth_event_name; 3514 int var_ref_idx, ret = 0; 3515 3516 lockdep_assert_held(&event_mutex); 3517 3518 if (data->use_trace_keyword) 3519 synth_event_name = data->synth_event_name; 3520 else 3521 synth_event_name = data->action_name; 3522 3523 event = find_synth_event(synth_event_name); 3524 if (!event) { 3525 hist_err(tr, HIST_ERR_SYNTH_EVENT_NOT_FOUND, errpos(synth_event_name)); 3526 return -EINVAL; 3527 } 3528 3529 event->ref++; 3530 3531 for (i = 0; i < data->n_params; i++) { 3532 char *p; 3533 3534 p = param = kstrdup(data->params[i], GFP_KERNEL); 3535 if (!param) { 3536 ret = -ENOMEM; 3537 goto err; 3538 } 3539 3540 system = strsep(¶m, "."); 3541 if (!param) { 3542 param = (char *)system; 3543 system = event_name = NULL; 3544 } else { 3545 event_name = strsep(¶m, "."); 3546 if (!param) { 3547 kfree(p); 3548 ret = -EINVAL; 3549 goto err; 3550 } 3551 } 3552 3553 if (param[0] == '$') 3554 hist_field = trace_action_find_var(hist_data, data, 3555 system, event_name, 3556 param); 3557 else 3558 hist_field = trace_action_create_field_var(hist_data, 3559 data, 3560 system, 3561 event_name, 3562 param); 3563 3564 if (!hist_field) { 3565 kfree(p); 3566 ret = -EINVAL; 3567 goto err; 3568 } 3569 3570 if (check_synth_field(event, hist_field, field_pos) == 0) { 3571 var_ref = create_var_ref(hist_data, hist_field, 3572 system, event_name); 3573 if (!var_ref) { 3574 kfree(p); 3575 ret = -ENOMEM; 3576 goto err; 3577 } 3578 3579 var_ref_idx = find_var_ref_idx(hist_data, var_ref); 3580 if (WARN_ON(var_ref_idx < 0)) { 3581 ret = var_ref_idx; 3582 goto err; 3583 } 3584 3585 data->var_ref_idx[i] = var_ref_idx; 3586 3587 field_pos++; 3588 kfree(p); 3589 continue; 3590 } 3591 3592 hist_err(tr, HIST_ERR_SYNTH_TYPE_MISMATCH, errpos(param)); 3593 kfree(p); 3594 ret = -EINVAL; 3595 goto err; 3596 } 3597 3598 if (field_pos != event->n_fields) { 3599 hist_err(tr, HIST_ERR_SYNTH_COUNT_MISMATCH, errpos(event->name)); 3600 ret = -EINVAL; 3601 goto err; 3602 } 3603 3604 data->synth_event = event; 3605 out: 3606 return ret; 3607 err: 3608 event->ref--; 3609 3610 goto out; 3611 } 3612 3613 static int action_create(struct hist_trigger_data *hist_data, 3614 struct action_data *data) 3615 { 3616 struct trace_event_file *file = hist_data->event_file; 3617 struct trace_array *tr = file->tr; 3618 struct track_data *track_data; 3619 struct field_var *field_var; 3620 unsigned int i; 3621 char *param; 3622 int ret = 0; 3623 3624 if (data->action == ACTION_TRACE) 3625 return trace_action_create(hist_data, data); 3626 3627 if (data->action == ACTION_SNAPSHOT) { 3628 track_data = track_data_alloc(hist_data->key_size, data, hist_data); 3629 if (IS_ERR(track_data)) { 3630 ret = PTR_ERR(track_data); 3631 goto out; 3632 } 3633 3634 ret = tracing_snapshot_cond_enable(file->tr, track_data, 3635 cond_snapshot_update); 3636 if (ret) 3637 track_data_free(track_data); 3638 3639 goto out; 3640 } 3641 3642 if (data->action == ACTION_SAVE) { 3643 if (hist_data->n_save_vars) { 3644 ret = -EEXIST; 3645 hist_err(tr, HIST_ERR_TOO_MANY_SAVE_ACTIONS, 0); 3646 goto out; 3647 } 3648 3649 for (i = 0; i < data->n_params; i++) { 3650 param = kstrdup(data->params[i], GFP_KERNEL); 3651 if (!param) { 3652 ret = -ENOMEM; 3653 goto out; 3654 } 3655 3656 field_var = create_target_field_var(hist_data, NULL, NULL, param); 3657 if (IS_ERR(field_var)) { 3658 hist_err(tr, HIST_ERR_FIELD_VAR_CREATE_FAIL, 3659 errpos(param)); 3660 ret = PTR_ERR(field_var); 3661 kfree(param); 3662 goto out; 3663 } 3664 3665 hist_data->save_vars[hist_data->n_save_vars++] = field_var; 3666 if (field_var->val->flags & HIST_FIELD_FL_STRING) 3667 hist_data->n_save_var_str++; 3668 kfree(param); 3669 } 3670 } 3671 out: 3672 return ret; 3673 } 3674 3675 static int onmatch_create(struct hist_trigger_data *hist_data, 3676 struct action_data *data) 3677 { 3678 return action_create(hist_data, data); 3679 } 3680 3681 static struct action_data *onmatch_parse(struct trace_array *tr, char *str) 3682 { 3683 char *match_event, *match_event_system; 3684 struct action_data *data; 3685 int ret = -EINVAL; 3686 3687 data = kzalloc(sizeof(*data), GFP_KERNEL); 3688 if (!data) 3689 return ERR_PTR(-ENOMEM); 3690 3691 match_event = strsep(&str, ")"); 3692 if (!match_event || !str) { 3693 hist_err(tr, HIST_ERR_NO_CLOSING_PAREN, errpos(match_event)); 3694 goto free; 3695 } 3696 3697 match_event_system = strsep(&match_event, "."); 3698 if (!match_event) { 3699 hist_err(tr, HIST_ERR_SUBSYS_NOT_FOUND, errpos(match_event_system)); 3700 goto free; 3701 } 3702 3703 if (IS_ERR(event_file(tr, match_event_system, match_event))) { 3704 hist_err(tr, HIST_ERR_INVALID_SUBSYS_EVENT, errpos(match_event)); 3705 goto free; 3706 } 3707 3708 data->match_data.event = kstrdup(match_event, GFP_KERNEL); 3709 if (!data->match_data.event) { 3710 ret = -ENOMEM; 3711 goto free; 3712 } 3713 3714 data->match_data.event_system = kstrdup(match_event_system, GFP_KERNEL); 3715 if (!data->match_data.event_system) { 3716 ret = -ENOMEM; 3717 goto free; 3718 } 3719 3720 ret = action_parse(tr, str, data, HANDLER_ONMATCH); 3721 if (ret) 3722 goto free; 3723 out: 3724 return data; 3725 free: 3726 onmatch_destroy(data); 3727 data = ERR_PTR(ret); 3728 goto out; 3729 } 3730 3731 static int create_hitcount_val(struct hist_trigger_data *hist_data) 3732 { 3733 hist_data->fields[HITCOUNT_IDX] = 3734 create_hist_field(hist_data, NULL, HIST_FIELD_FL_HITCOUNT, NULL); 3735 if (!hist_data->fields[HITCOUNT_IDX]) 3736 return -ENOMEM; 3737 3738 hist_data->n_vals++; 3739 hist_data->n_fields++; 3740 3741 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX)) 3742 return -EINVAL; 3743 3744 return 0; 3745 } 3746 3747 static int __create_val_field(struct hist_trigger_data *hist_data, 3748 unsigned int val_idx, 3749 struct trace_event_file *file, 3750 char *var_name, char *field_str, 3751 unsigned long flags) 3752 { 3753 struct hist_field *hist_field; 3754 int ret = 0; 3755 3756 hist_field = parse_expr(hist_data, file, field_str, flags, var_name, 0); 3757 if (IS_ERR(hist_field)) { 3758 ret = PTR_ERR(hist_field); 3759 goto out; 3760 } 3761 3762 hist_data->fields[val_idx] = hist_field; 3763 3764 ++hist_data->n_vals; 3765 ++hist_data->n_fields; 3766 3767 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX)) 3768 ret = -EINVAL; 3769 out: 3770 return ret; 3771 } 3772 3773 static int create_val_field(struct hist_trigger_data *hist_data, 3774 unsigned int val_idx, 3775 struct trace_event_file *file, 3776 char *field_str) 3777 { 3778 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX)) 3779 return -EINVAL; 3780 3781 return __create_val_field(hist_data, val_idx, file, NULL, field_str, 0); 3782 } 3783 3784 static const char *no_comm = "(no comm)"; 3785 3786 static u64 hist_field_execname(struct hist_field *hist_field, 3787 struct tracing_map_elt *elt, 3788 struct trace_buffer *buffer, 3789 struct ring_buffer_event *rbe, 3790 void *event) 3791 { 3792 struct hist_elt_data *elt_data; 3793 3794 if (WARN_ON_ONCE(!elt)) 3795 return (u64)(unsigned long)no_comm; 3796 3797 elt_data = elt->private_data; 3798 3799 if (WARN_ON_ONCE(!elt_data->comm)) 3800 return (u64)(unsigned long)no_comm; 3801 3802 return (u64)(unsigned long)(elt_data->comm); 3803 } 3804 3805 /* Convert a var that points to common_pid.execname to a string */ 3806 static void update_var_execname(struct hist_field *hist_field) 3807 { 3808 hist_field->flags = HIST_FIELD_FL_STRING | HIST_FIELD_FL_VAR | 3809 HIST_FIELD_FL_EXECNAME; 3810 hist_field->size = MAX_FILTER_STR_VAL; 3811 hist_field->is_signed = 0; 3812 3813 kfree_const(hist_field->type); 3814 hist_field->type = "char[]"; 3815 3816 hist_field->fn = hist_field_execname; 3817 } 3818 3819 static int create_var_field(struct hist_trigger_data *hist_data, 3820 unsigned int val_idx, 3821 struct trace_event_file *file, 3822 char *var_name, char *expr_str) 3823 { 3824 struct trace_array *tr = hist_data->event_file->tr; 3825 unsigned long flags = 0; 3826 int ret; 3827 3828 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX)) 3829 return -EINVAL; 3830 3831 if (find_var(hist_data, file, var_name) && !hist_data->remove) { 3832 hist_err(tr, HIST_ERR_DUPLICATE_VAR, errpos(var_name)); 3833 return -EINVAL; 3834 } 3835 3836 flags |= HIST_FIELD_FL_VAR; 3837 hist_data->n_vars++; 3838 if (WARN_ON(hist_data->n_vars > TRACING_MAP_VARS_MAX)) 3839 return -EINVAL; 3840 3841 ret = __create_val_field(hist_data, val_idx, file, var_name, expr_str, flags); 3842 3843 if (!ret && hist_data->fields[val_idx]->flags & HIST_FIELD_FL_EXECNAME) 3844 update_var_execname(hist_data->fields[val_idx]); 3845 3846 if (!ret && hist_data->fields[val_idx]->flags & HIST_FIELD_FL_STRING) 3847 hist_data->fields[val_idx]->var_str_idx = hist_data->n_var_str++; 3848 3849 return ret; 3850 } 3851 3852 static int create_val_fields(struct hist_trigger_data *hist_data, 3853 struct trace_event_file *file) 3854 { 3855 char *fields_str, *field_str; 3856 unsigned int i, j = 1; 3857 int ret; 3858 3859 ret = create_hitcount_val(hist_data); 3860 if (ret) 3861 goto out; 3862 3863 fields_str = hist_data->attrs->vals_str; 3864 if (!fields_str) 3865 goto out; 3866 3867 for (i = 0, j = 1; i < TRACING_MAP_VALS_MAX && 3868 j < TRACING_MAP_VALS_MAX; i++) { 3869 field_str = strsep(&fields_str, ","); 3870 if (!field_str) 3871 break; 3872 3873 if (strcmp(field_str, "hitcount") == 0) 3874 continue; 3875 3876 ret = create_val_field(hist_data, j++, file, field_str); 3877 if (ret) 3878 goto out; 3879 } 3880 3881 if (fields_str && (strcmp(fields_str, "hitcount") != 0)) 3882 ret = -EINVAL; 3883 out: 3884 return ret; 3885 } 3886 3887 static int create_key_field(struct hist_trigger_data *hist_data, 3888 unsigned int key_idx, 3889 unsigned int key_offset, 3890 struct trace_event_file *file, 3891 char *field_str) 3892 { 3893 struct trace_array *tr = hist_data->event_file->tr; 3894 struct hist_field *hist_field = NULL; 3895 unsigned long flags = 0; 3896 unsigned int key_size; 3897 int ret = 0; 3898 3899 if (WARN_ON(key_idx >= HIST_FIELDS_MAX)) 3900 return -EINVAL; 3901 3902 flags |= HIST_FIELD_FL_KEY; 3903 3904 if (strcmp(field_str, "stacktrace") == 0) { 3905 flags |= HIST_FIELD_FL_STACKTRACE; 3906 key_size = sizeof(unsigned long) * HIST_STACKTRACE_DEPTH; 3907 hist_field = create_hist_field(hist_data, NULL, flags, NULL); 3908 } else { 3909 hist_field = parse_expr(hist_data, file, field_str, flags, 3910 NULL, 0); 3911 if (IS_ERR(hist_field)) { 3912 ret = PTR_ERR(hist_field); 3913 goto out; 3914 } 3915 3916 if (field_has_hist_vars(hist_field, 0)) { 3917 hist_err(tr, HIST_ERR_INVALID_REF_KEY, errpos(field_str)); 3918 destroy_hist_field(hist_field, 0); 3919 ret = -EINVAL; 3920 goto out; 3921 } 3922 3923 key_size = hist_field->size; 3924 } 3925 3926 hist_data->fields[key_idx] = hist_field; 3927 3928 key_size = ALIGN(key_size, sizeof(u64)); 3929 hist_data->fields[key_idx]->size = key_size; 3930 hist_data->fields[key_idx]->offset = key_offset; 3931 3932 hist_data->key_size += key_size; 3933 3934 if (hist_data->key_size > HIST_KEY_SIZE_MAX) { 3935 ret = -EINVAL; 3936 goto out; 3937 } 3938 3939 hist_data->n_keys++; 3940 hist_data->n_fields++; 3941 3942 if (WARN_ON(hist_data->n_keys > TRACING_MAP_KEYS_MAX)) 3943 return -EINVAL; 3944 3945 ret = key_size; 3946 out: 3947 return ret; 3948 } 3949 3950 static int create_key_fields(struct hist_trigger_data *hist_data, 3951 struct trace_event_file *file) 3952 { 3953 unsigned int i, key_offset = 0, n_vals = hist_data->n_vals; 3954 char *fields_str, *field_str; 3955 int ret = -EINVAL; 3956 3957 fields_str = hist_data->attrs->keys_str; 3958 if (!fields_str) 3959 goto out; 3960 3961 for (i = n_vals; i < n_vals + TRACING_MAP_KEYS_MAX; i++) { 3962 field_str = strsep(&fields_str, ","); 3963 if (!field_str) 3964 break; 3965 ret = create_key_field(hist_data, i, key_offset, 3966 file, field_str); 3967 if (ret < 0) 3968 goto out; 3969 key_offset += ret; 3970 } 3971 if (fields_str) { 3972 ret = -EINVAL; 3973 goto out; 3974 } 3975 ret = 0; 3976 out: 3977 return ret; 3978 } 3979 3980 static int create_var_fields(struct hist_trigger_data *hist_data, 3981 struct trace_event_file *file) 3982 { 3983 unsigned int i, j = hist_data->n_vals; 3984 int ret = 0; 3985 3986 unsigned int n_vars = hist_data->attrs->var_defs.n_vars; 3987 3988 for (i = 0; i < n_vars; i++) { 3989 char *var_name = hist_data->attrs->var_defs.name[i]; 3990 char *expr = hist_data->attrs->var_defs.expr[i]; 3991 3992 ret = create_var_field(hist_data, j++, file, var_name, expr); 3993 if (ret) 3994 goto out; 3995 } 3996 out: 3997 return ret; 3998 } 3999 4000 static void free_var_defs(struct hist_trigger_data *hist_data) 4001 { 4002 unsigned int i; 4003 4004 for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) { 4005 kfree(hist_data->attrs->var_defs.name[i]); 4006 kfree(hist_data->attrs->var_defs.expr[i]); 4007 } 4008 4009 hist_data->attrs->var_defs.n_vars = 0; 4010 } 4011 4012 static int parse_var_defs(struct hist_trigger_data *hist_data) 4013 { 4014 struct trace_array *tr = hist_data->event_file->tr; 4015 char *s, *str, *var_name, *field_str; 4016 unsigned int i, j, n_vars = 0; 4017 int ret = 0; 4018 4019 for (i = 0; i < hist_data->attrs->n_assignments; i++) { 4020 str = hist_data->attrs->assignment_str[i]; 4021 for (j = 0; j < TRACING_MAP_VARS_MAX; j++) { 4022 field_str = strsep(&str, ","); 4023 if (!field_str) 4024 break; 4025 4026 var_name = strsep(&field_str, "="); 4027 if (!var_name || !field_str) { 4028 hist_err(tr, HIST_ERR_MALFORMED_ASSIGNMENT, 4029 errpos(var_name)); 4030 ret = -EINVAL; 4031 goto free; 4032 } 4033 4034 if (n_vars == TRACING_MAP_VARS_MAX) { 4035 hist_err(tr, HIST_ERR_TOO_MANY_VARS, errpos(var_name)); 4036 ret = -EINVAL; 4037 goto free; 4038 } 4039 4040 s = kstrdup(var_name, GFP_KERNEL); 4041 if (!s) { 4042 ret = -ENOMEM; 4043 goto free; 4044 } 4045 hist_data->attrs->var_defs.name[n_vars] = s; 4046 4047 s = kstrdup(field_str, GFP_KERNEL); 4048 if (!s) { 4049 ret = -ENOMEM; 4050 goto free; 4051 } 4052 hist_data->attrs->var_defs.expr[n_vars++] = s; 4053 4054 hist_data->attrs->var_defs.n_vars = n_vars; 4055 } 4056 } 4057 4058 return ret; 4059 free: 4060 free_var_defs(hist_data); 4061 4062 return ret; 4063 } 4064 4065 static int create_hist_fields(struct hist_trigger_data *hist_data, 4066 struct trace_event_file *file) 4067 { 4068 int ret; 4069 4070 ret = parse_var_defs(hist_data); 4071 if (ret) 4072 goto out; 4073 4074 ret = create_val_fields(hist_data, file); 4075 if (ret) 4076 goto out; 4077 4078 ret = create_var_fields(hist_data, file); 4079 if (ret) 4080 goto out; 4081 4082 ret = create_key_fields(hist_data, file); 4083 if (ret) 4084 goto out; 4085 out: 4086 free_var_defs(hist_data); 4087 4088 return ret; 4089 } 4090 4091 static int is_descending(struct trace_array *tr, const char *str) 4092 { 4093 if (!str) 4094 return 0; 4095 4096 if (strcmp(str, "descending") == 0) 4097 return 1; 4098 4099 if (strcmp(str, "ascending") == 0) 4100 return 0; 4101 4102 hist_err(tr, HIST_ERR_INVALID_SORT_MODIFIER, errpos((char *)str)); 4103 4104 return -EINVAL; 4105 } 4106 4107 static int create_sort_keys(struct hist_trigger_data *hist_data) 4108 { 4109 struct trace_array *tr = hist_data->event_file->tr; 4110 char *fields_str = hist_data->attrs->sort_key_str; 4111 struct tracing_map_sort_key *sort_key; 4112 int descending, ret = 0; 4113 unsigned int i, j, k; 4114 4115 hist_data->n_sort_keys = 1; /* we always have at least one, hitcount */ 4116 4117 if (!fields_str) 4118 goto out; 4119 4120 for (i = 0; i < TRACING_MAP_SORT_KEYS_MAX; i++) { 4121 struct hist_field *hist_field; 4122 char *field_str, *field_name; 4123 const char *test_name; 4124 4125 sort_key = &hist_data->sort_keys[i]; 4126 4127 field_str = strsep(&fields_str, ","); 4128 if (!field_str) 4129 break; 4130 4131 if (!*field_str) { 4132 ret = -EINVAL; 4133 hist_err(tr, HIST_ERR_EMPTY_SORT_FIELD, errpos("sort=")); 4134 break; 4135 } 4136 4137 if ((i == TRACING_MAP_SORT_KEYS_MAX - 1) && fields_str) { 4138 hist_err(tr, HIST_ERR_TOO_MANY_SORT_FIELDS, errpos("sort=")); 4139 ret = -EINVAL; 4140 break; 4141 } 4142 4143 field_name = strsep(&field_str, "."); 4144 if (!field_name || !*field_name) { 4145 ret = -EINVAL; 4146 hist_err(tr, HIST_ERR_EMPTY_SORT_FIELD, errpos("sort=")); 4147 break; 4148 } 4149 4150 if (strcmp(field_name, "hitcount") == 0) { 4151 descending = is_descending(tr, field_str); 4152 if (descending < 0) { 4153 ret = descending; 4154 break; 4155 } 4156 sort_key->descending = descending; 4157 continue; 4158 } 4159 4160 for (j = 1, k = 1; j < hist_data->n_fields; j++) { 4161 unsigned int idx; 4162 4163 hist_field = hist_data->fields[j]; 4164 if (hist_field->flags & HIST_FIELD_FL_VAR) 4165 continue; 4166 4167 idx = k++; 4168 4169 test_name = hist_field_name(hist_field, 0); 4170 4171 if (strcmp(field_name, test_name) == 0) { 4172 sort_key->field_idx = idx; 4173 descending = is_descending(tr, field_str); 4174 if (descending < 0) { 4175 ret = descending; 4176 goto out; 4177 } 4178 sort_key->descending = descending; 4179 break; 4180 } 4181 } 4182 if (j == hist_data->n_fields) { 4183 ret = -EINVAL; 4184 hist_err(tr, HIST_ERR_INVALID_SORT_FIELD, errpos(field_name)); 4185 break; 4186 } 4187 } 4188 4189 hist_data->n_sort_keys = i; 4190 out: 4191 return ret; 4192 } 4193 4194 static void destroy_actions(struct hist_trigger_data *hist_data) 4195 { 4196 unsigned int i; 4197 4198 for (i = 0; i < hist_data->n_actions; i++) { 4199 struct action_data *data = hist_data->actions[i]; 4200 4201 if (data->handler == HANDLER_ONMATCH) 4202 onmatch_destroy(data); 4203 else if (data->handler == HANDLER_ONMAX || 4204 data->handler == HANDLER_ONCHANGE) 4205 track_data_destroy(hist_data, data); 4206 else 4207 kfree(data); 4208 } 4209 } 4210 4211 static int parse_actions(struct hist_trigger_data *hist_data) 4212 { 4213 struct trace_array *tr = hist_data->event_file->tr; 4214 struct action_data *data; 4215 unsigned int i; 4216 int ret = 0; 4217 char *str; 4218 int len; 4219 4220 for (i = 0; i < hist_data->attrs->n_actions; i++) { 4221 str = hist_data->attrs->action_str[i]; 4222 4223 if ((len = str_has_prefix(str, "onmatch("))) { 4224 char *action_str = str + len; 4225 4226 data = onmatch_parse(tr, action_str); 4227 if (IS_ERR(data)) { 4228 ret = PTR_ERR(data); 4229 break; 4230 } 4231 } else if ((len = str_has_prefix(str, "onmax("))) { 4232 char *action_str = str + len; 4233 4234 data = track_data_parse(hist_data, action_str, 4235 HANDLER_ONMAX); 4236 if (IS_ERR(data)) { 4237 ret = PTR_ERR(data); 4238 break; 4239 } 4240 } else if ((len = str_has_prefix(str, "onchange("))) { 4241 char *action_str = str + len; 4242 4243 data = track_data_parse(hist_data, action_str, 4244 HANDLER_ONCHANGE); 4245 if (IS_ERR(data)) { 4246 ret = PTR_ERR(data); 4247 break; 4248 } 4249 } else { 4250 ret = -EINVAL; 4251 break; 4252 } 4253 4254 hist_data->actions[hist_data->n_actions++] = data; 4255 } 4256 4257 return ret; 4258 } 4259 4260 static int create_actions(struct hist_trigger_data *hist_data) 4261 { 4262 struct action_data *data; 4263 unsigned int i; 4264 int ret = 0; 4265 4266 for (i = 0; i < hist_data->attrs->n_actions; i++) { 4267 data = hist_data->actions[i]; 4268 4269 if (data->handler == HANDLER_ONMATCH) { 4270 ret = onmatch_create(hist_data, data); 4271 if (ret) 4272 break; 4273 } else if (data->handler == HANDLER_ONMAX || 4274 data->handler == HANDLER_ONCHANGE) { 4275 ret = track_data_create(hist_data, data); 4276 if (ret) 4277 break; 4278 } else { 4279 ret = -EINVAL; 4280 break; 4281 } 4282 } 4283 4284 return ret; 4285 } 4286 4287 static void print_actions(struct seq_file *m, 4288 struct hist_trigger_data *hist_data, 4289 struct tracing_map_elt *elt) 4290 { 4291 unsigned int i; 4292 4293 for (i = 0; i < hist_data->n_actions; i++) { 4294 struct action_data *data = hist_data->actions[i]; 4295 4296 if (data->action == ACTION_SNAPSHOT) 4297 continue; 4298 4299 if (data->handler == HANDLER_ONMAX || 4300 data->handler == HANDLER_ONCHANGE) 4301 track_data_print(m, hist_data, elt, data); 4302 } 4303 } 4304 4305 static void print_action_spec(struct seq_file *m, 4306 struct hist_trigger_data *hist_data, 4307 struct action_data *data) 4308 { 4309 unsigned int i; 4310 4311 if (data->action == ACTION_SAVE) { 4312 for (i = 0; i < hist_data->n_save_vars; i++) { 4313 seq_printf(m, "%s", hist_data->save_vars[i]->var->var.name); 4314 if (i < hist_data->n_save_vars - 1) 4315 seq_puts(m, ","); 4316 } 4317 } else if (data->action == ACTION_TRACE) { 4318 if (data->use_trace_keyword) 4319 seq_printf(m, "%s", data->synth_event_name); 4320 for (i = 0; i < data->n_params; i++) { 4321 if (i || data->use_trace_keyword) 4322 seq_puts(m, ","); 4323 seq_printf(m, "%s", data->params[i]); 4324 } 4325 } 4326 } 4327 4328 static void print_track_data_spec(struct seq_file *m, 4329 struct hist_trigger_data *hist_data, 4330 struct action_data *data) 4331 { 4332 if (data->handler == HANDLER_ONMAX) 4333 seq_puts(m, ":onmax("); 4334 else if (data->handler == HANDLER_ONCHANGE) 4335 seq_puts(m, ":onchange("); 4336 seq_printf(m, "%s", data->track_data.var_str); 4337 seq_printf(m, ").%s(", data->action_name); 4338 4339 print_action_spec(m, hist_data, data); 4340 4341 seq_puts(m, ")"); 4342 } 4343 4344 static void print_onmatch_spec(struct seq_file *m, 4345 struct hist_trigger_data *hist_data, 4346 struct action_data *data) 4347 { 4348 seq_printf(m, ":onmatch(%s.%s).", data->match_data.event_system, 4349 data->match_data.event); 4350 4351 seq_printf(m, "%s(", data->action_name); 4352 4353 print_action_spec(m, hist_data, data); 4354 4355 seq_puts(m, ")"); 4356 } 4357 4358 static bool actions_match(struct hist_trigger_data *hist_data, 4359 struct hist_trigger_data *hist_data_test) 4360 { 4361 unsigned int i, j; 4362 4363 if (hist_data->n_actions != hist_data_test->n_actions) 4364 return false; 4365 4366 for (i = 0; i < hist_data->n_actions; i++) { 4367 struct action_data *data = hist_data->actions[i]; 4368 struct action_data *data_test = hist_data_test->actions[i]; 4369 char *action_name, *action_name_test; 4370 4371 if (data->handler != data_test->handler) 4372 return false; 4373 if (data->action != data_test->action) 4374 return false; 4375 4376 if (data->n_params != data_test->n_params) 4377 return false; 4378 4379 for (j = 0; j < data->n_params; j++) { 4380 if (strcmp(data->params[j], data_test->params[j]) != 0) 4381 return false; 4382 } 4383 4384 if (data->use_trace_keyword) 4385 action_name = data->synth_event_name; 4386 else 4387 action_name = data->action_name; 4388 4389 if (data_test->use_trace_keyword) 4390 action_name_test = data_test->synth_event_name; 4391 else 4392 action_name_test = data_test->action_name; 4393 4394 if (strcmp(action_name, action_name_test) != 0) 4395 return false; 4396 4397 if (data->handler == HANDLER_ONMATCH) { 4398 if (strcmp(data->match_data.event_system, 4399 data_test->match_data.event_system) != 0) 4400 return false; 4401 if (strcmp(data->match_data.event, 4402 data_test->match_data.event) != 0) 4403 return false; 4404 } else if (data->handler == HANDLER_ONMAX || 4405 data->handler == HANDLER_ONCHANGE) { 4406 if (strcmp(data->track_data.var_str, 4407 data_test->track_data.var_str) != 0) 4408 return false; 4409 } 4410 } 4411 4412 return true; 4413 } 4414 4415 4416 static void print_actions_spec(struct seq_file *m, 4417 struct hist_trigger_data *hist_data) 4418 { 4419 unsigned int i; 4420 4421 for (i = 0; i < hist_data->n_actions; i++) { 4422 struct action_data *data = hist_data->actions[i]; 4423 4424 if (data->handler == HANDLER_ONMATCH) 4425 print_onmatch_spec(m, hist_data, data); 4426 else if (data->handler == HANDLER_ONMAX || 4427 data->handler == HANDLER_ONCHANGE) 4428 print_track_data_spec(m, hist_data, data); 4429 } 4430 } 4431 4432 static void destroy_field_var_hists(struct hist_trigger_data *hist_data) 4433 { 4434 unsigned int i; 4435 4436 for (i = 0; i < hist_data->n_field_var_hists; i++) { 4437 kfree(hist_data->field_var_hists[i]->cmd); 4438 kfree(hist_data->field_var_hists[i]); 4439 } 4440 } 4441 4442 static void destroy_hist_data(struct hist_trigger_data *hist_data) 4443 { 4444 if (!hist_data) 4445 return; 4446 4447 destroy_hist_trigger_attrs(hist_data->attrs); 4448 destroy_hist_fields(hist_data); 4449 tracing_map_destroy(hist_data->map); 4450 4451 destroy_actions(hist_data); 4452 destroy_field_vars(hist_data); 4453 destroy_field_var_hists(hist_data); 4454 4455 kfree(hist_data); 4456 } 4457 4458 static int create_tracing_map_fields(struct hist_trigger_data *hist_data) 4459 { 4460 struct tracing_map *map = hist_data->map; 4461 struct ftrace_event_field *field; 4462 struct hist_field *hist_field; 4463 int i, idx = 0; 4464 4465 for_each_hist_field(i, hist_data) { 4466 hist_field = hist_data->fields[i]; 4467 if (hist_field->flags & HIST_FIELD_FL_KEY) { 4468 tracing_map_cmp_fn_t cmp_fn; 4469 4470 field = hist_field->field; 4471 4472 if (hist_field->flags & HIST_FIELD_FL_STACKTRACE) 4473 cmp_fn = tracing_map_cmp_none; 4474 else if (!field) 4475 cmp_fn = tracing_map_cmp_num(hist_field->size, 4476 hist_field->is_signed); 4477 else if (is_string_field(field)) 4478 cmp_fn = tracing_map_cmp_string; 4479 else 4480 cmp_fn = tracing_map_cmp_num(field->size, 4481 field->is_signed); 4482 idx = tracing_map_add_key_field(map, 4483 hist_field->offset, 4484 cmp_fn); 4485 } else if (!(hist_field->flags & HIST_FIELD_FL_VAR)) 4486 idx = tracing_map_add_sum_field(map); 4487 4488 if (idx < 0) 4489 return idx; 4490 4491 if (hist_field->flags & HIST_FIELD_FL_VAR) { 4492 idx = tracing_map_add_var(map); 4493 if (idx < 0) 4494 return idx; 4495 hist_field->var.idx = idx; 4496 hist_field->var.hist_data = hist_data; 4497 } 4498 } 4499 4500 return 0; 4501 } 4502 4503 static struct hist_trigger_data * 4504 create_hist_data(unsigned int map_bits, 4505 struct hist_trigger_attrs *attrs, 4506 struct trace_event_file *file, 4507 bool remove) 4508 { 4509 const struct tracing_map_ops *map_ops = NULL; 4510 struct hist_trigger_data *hist_data; 4511 int ret = 0; 4512 4513 hist_data = kzalloc(sizeof(*hist_data), GFP_KERNEL); 4514 if (!hist_data) 4515 return ERR_PTR(-ENOMEM); 4516 4517 hist_data->attrs = attrs; 4518 hist_data->remove = remove; 4519 hist_data->event_file = file; 4520 4521 ret = parse_actions(hist_data); 4522 if (ret) 4523 goto free; 4524 4525 ret = create_hist_fields(hist_data, file); 4526 if (ret) 4527 goto free; 4528 4529 ret = create_sort_keys(hist_data); 4530 if (ret) 4531 goto free; 4532 4533 map_ops = &hist_trigger_elt_data_ops; 4534 4535 hist_data->map = tracing_map_create(map_bits, hist_data->key_size, 4536 map_ops, hist_data); 4537 if (IS_ERR(hist_data->map)) { 4538 ret = PTR_ERR(hist_data->map); 4539 hist_data->map = NULL; 4540 goto free; 4541 } 4542 4543 ret = create_tracing_map_fields(hist_data); 4544 if (ret) 4545 goto free; 4546 out: 4547 return hist_data; 4548 free: 4549 hist_data->attrs = NULL; 4550 4551 destroy_hist_data(hist_data); 4552 4553 hist_data = ERR_PTR(ret); 4554 4555 goto out; 4556 } 4557 4558 static void hist_trigger_elt_update(struct hist_trigger_data *hist_data, 4559 struct tracing_map_elt *elt, 4560 struct trace_buffer *buffer, void *rec, 4561 struct ring_buffer_event *rbe, 4562 u64 *var_ref_vals) 4563 { 4564 struct hist_elt_data *elt_data; 4565 struct hist_field *hist_field; 4566 unsigned int i, var_idx; 4567 u64 hist_val; 4568 4569 elt_data = elt->private_data; 4570 elt_data->var_ref_vals = var_ref_vals; 4571 4572 for_each_hist_val_field(i, hist_data) { 4573 hist_field = hist_data->fields[i]; 4574 hist_val = hist_field->fn(hist_field, elt, buffer, rbe, rec); 4575 if (hist_field->flags & HIST_FIELD_FL_VAR) { 4576 var_idx = hist_field->var.idx; 4577 4578 if (hist_field->flags & HIST_FIELD_FL_STRING) { 4579 unsigned int str_start, var_str_idx, idx; 4580 char *str, *val_str; 4581 4582 str_start = hist_data->n_field_var_str + 4583 hist_data->n_save_var_str; 4584 var_str_idx = hist_field->var_str_idx; 4585 idx = str_start + var_str_idx; 4586 4587 str = elt_data->field_var_str[idx]; 4588 val_str = (char *)(uintptr_t)hist_val; 4589 strscpy(str, val_str, STR_VAR_LEN_MAX); 4590 4591 hist_val = (u64)(uintptr_t)str; 4592 } 4593 tracing_map_set_var(elt, var_idx, hist_val); 4594 continue; 4595 } 4596 tracing_map_update_sum(elt, i, hist_val); 4597 } 4598 4599 for_each_hist_key_field(i, hist_data) { 4600 hist_field = hist_data->fields[i]; 4601 if (hist_field->flags & HIST_FIELD_FL_VAR) { 4602 hist_val = hist_field->fn(hist_field, elt, buffer, rbe, rec); 4603 var_idx = hist_field->var.idx; 4604 tracing_map_set_var(elt, var_idx, hist_val); 4605 } 4606 } 4607 4608 update_field_vars(hist_data, elt, buffer, rbe, rec); 4609 } 4610 4611 static inline void add_to_key(char *compound_key, void *key, 4612 struct hist_field *key_field, void *rec) 4613 { 4614 size_t size = key_field->size; 4615 4616 if (key_field->flags & HIST_FIELD_FL_STRING) { 4617 struct ftrace_event_field *field; 4618 4619 field = key_field->field; 4620 if (field->filter_type == FILTER_DYN_STRING) 4621 size = *(u32 *)(rec + field->offset) >> 16; 4622 else if (field->filter_type == FILTER_STATIC_STRING) 4623 size = field->size; 4624 4625 /* ensure NULL-termination */ 4626 if (size > key_field->size - 1) 4627 size = key_field->size - 1; 4628 4629 strncpy(compound_key + key_field->offset, (char *)key, size); 4630 } else 4631 memcpy(compound_key + key_field->offset, key, size); 4632 } 4633 4634 static void 4635 hist_trigger_actions(struct hist_trigger_data *hist_data, 4636 struct tracing_map_elt *elt, 4637 struct trace_buffer *buffer, void *rec, 4638 struct ring_buffer_event *rbe, void *key, 4639 u64 *var_ref_vals) 4640 { 4641 struct action_data *data; 4642 unsigned int i; 4643 4644 for (i = 0; i < hist_data->n_actions; i++) { 4645 data = hist_data->actions[i]; 4646 data->fn(hist_data, elt, buffer, rec, rbe, key, data, var_ref_vals); 4647 } 4648 } 4649 4650 static void event_hist_trigger(struct event_trigger_data *data, 4651 struct trace_buffer *buffer, void *rec, 4652 struct ring_buffer_event *rbe) 4653 { 4654 struct hist_trigger_data *hist_data = data->private_data; 4655 bool use_compound_key = (hist_data->n_keys > 1); 4656 unsigned long entries[HIST_STACKTRACE_DEPTH]; 4657 u64 var_ref_vals[TRACING_MAP_VARS_MAX]; 4658 char compound_key[HIST_KEY_SIZE_MAX]; 4659 struct tracing_map_elt *elt = NULL; 4660 struct hist_field *key_field; 4661 u64 field_contents; 4662 void *key = NULL; 4663 unsigned int i; 4664 4665 memset(compound_key, 0, hist_data->key_size); 4666 4667 for_each_hist_key_field(i, hist_data) { 4668 key_field = hist_data->fields[i]; 4669 4670 if (key_field->flags & HIST_FIELD_FL_STACKTRACE) { 4671 memset(entries, 0, HIST_STACKTRACE_SIZE); 4672 stack_trace_save(entries, HIST_STACKTRACE_DEPTH, 4673 HIST_STACKTRACE_SKIP); 4674 key = entries; 4675 } else { 4676 field_contents = key_field->fn(key_field, elt, buffer, rbe, rec); 4677 if (key_field->flags & HIST_FIELD_FL_STRING) { 4678 key = (void *)(unsigned long)field_contents; 4679 use_compound_key = true; 4680 } else 4681 key = (void *)&field_contents; 4682 } 4683 4684 if (use_compound_key) 4685 add_to_key(compound_key, key, key_field, rec); 4686 } 4687 4688 if (use_compound_key) 4689 key = compound_key; 4690 4691 if (hist_data->n_var_refs && 4692 !resolve_var_refs(hist_data, key, var_ref_vals, false)) 4693 return; 4694 4695 elt = tracing_map_insert(hist_data->map, key); 4696 if (!elt) 4697 return; 4698 4699 hist_trigger_elt_update(hist_data, elt, buffer, rec, rbe, var_ref_vals); 4700 4701 if (resolve_var_refs(hist_data, key, var_ref_vals, true)) 4702 hist_trigger_actions(hist_data, elt, buffer, rec, rbe, key, var_ref_vals); 4703 } 4704 4705 static void hist_trigger_stacktrace_print(struct seq_file *m, 4706 unsigned long *stacktrace_entries, 4707 unsigned int max_entries) 4708 { 4709 char str[KSYM_SYMBOL_LEN]; 4710 unsigned int spaces = 8; 4711 unsigned int i; 4712 4713 for (i = 0; i < max_entries; i++) { 4714 if (!stacktrace_entries[i]) 4715 return; 4716 4717 seq_printf(m, "%*c", 1 + spaces, ' '); 4718 sprint_symbol(str, stacktrace_entries[i]); 4719 seq_printf(m, "%s\n", str); 4720 } 4721 } 4722 4723 static void hist_trigger_print_key(struct seq_file *m, 4724 struct hist_trigger_data *hist_data, 4725 void *key, 4726 struct tracing_map_elt *elt) 4727 { 4728 struct hist_field *key_field; 4729 char str[KSYM_SYMBOL_LEN]; 4730 bool multiline = false; 4731 const char *field_name; 4732 unsigned int i; 4733 u64 uval; 4734 4735 seq_puts(m, "{ "); 4736 4737 for_each_hist_key_field(i, hist_data) { 4738 key_field = hist_data->fields[i]; 4739 4740 if (i > hist_data->n_vals) 4741 seq_puts(m, ", "); 4742 4743 field_name = hist_field_name(key_field, 0); 4744 4745 if (key_field->flags & HIST_FIELD_FL_HEX) { 4746 uval = *(u64 *)(key + key_field->offset); 4747 seq_printf(m, "%s: %llx", field_name, uval); 4748 } else if (key_field->flags & HIST_FIELD_FL_SYM) { 4749 uval = *(u64 *)(key + key_field->offset); 4750 sprint_symbol_no_offset(str, uval); 4751 seq_printf(m, "%s: [%llx] %-45s", field_name, 4752 uval, str); 4753 } else if (key_field->flags & HIST_FIELD_FL_SYM_OFFSET) { 4754 uval = *(u64 *)(key + key_field->offset); 4755 sprint_symbol(str, uval); 4756 seq_printf(m, "%s: [%llx] %-55s", field_name, 4757 uval, str); 4758 } else if (key_field->flags & HIST_FIELD_FL_EXECNAME) { 4759 struct hist_elt_data *elt_data = elt->private_data; 4760 char *comm; 4761 4762 if (WARN_ON_ONCE(!elt_data)) 4763 return; 4764 4765 comm = elt_data->comm; 4766 4767 uval = *(u64 *)(key + key_field->offset); 4768 seq_printf(m, "%s: %-16s[%10llu]", field_name, 4769 comm, uval); 4770 } else if (key_field->flags & HIST_FIELD_FL_SYSCALL) { 4771 const char *syscall_name; 4772 4773 uval = *(u64 *)(key + key_field->offset); 4774 syscall_name = get_syscall_name(uval); 4775 if (!syscall_name) 4776 syscall_name = "unknown_syscall"; 4777 4778 seq_printf(m, "%s: %-30s[%3llu]", field_name, 4779 syscall_name, uval); 4780 } else if (key_field->flags & HIST_FIELD_FL_STACKTRACE) { 4781 seq_puts(m, "stacktrace:\n"); 4782 hist_trigger_stacktrace_print(m, 4783 key + key_field->offset, 4784 HIST_STACKTRACE_DEPTH); 4785 multiline = true; 4786 } else if (key_field->flags & HIST_FIELD_FL_LOG2) { 4787 seq_printf(m, "%s: ~ 2^%-2llu", field_name, 4788 *(u64 *)(key + key_field->offset)); 4789 } else if (key_field->flags & HIST_FIELD_FL_BUCKET) { 4790 unsigned long buckets = key_field->buckets; 4791 uval = *(u64 *)(key + key_field->offset); 4792 seq_printf(m, "%s: ~ %llu-%llu", field_name, 4793 uval, uval + buckets -1); 4794 } else if (key_field->flags & HIST_FIELD_FL_STRING) { 4795 seq_printf(m, "%s: %-50s", field_name, 4796 (char *)(key + key_field->offset)); 4797 } else { 4798 uval = *(u64 *)(key + key_field->offset); 4799 seq_printf(m, "%s: %10llu", field_name, uval); 4800 } 4801 } 4802 4803 if (!multiline) 4804 seq_puts(m, " "); 4805 4806 seq_puts(m, "}"); 4807 } 4808 4809 static void hist_trigger_entry_print(struct seq_file *m, 4810 struct hist_trigger_data *hist_data, 4811 void *key, 4812 struct tracing_map_elt *elt) 4813 { 4814 const char *field_name; 4815 unsigned int i; 4816 4817 hist_trigger_print_key(m, hist_data, key, elt); 4818 4819 seq_printf(m, " hitcount: %10llu", 4820 tracing_map_read_sum(elt, HITCOUNT_IDX)); 4821 4822 for (i = 1; i < hist_data->n_vals; i++) { 4823 field_name = hist_field_name(hist_data->fields[i], 0); 4824 4825 if (hist_data->fields[i]->flags & HIST_FIELD_FL_VAR || 4826 hist_data->fields[i]->flags & HIST_FIELD_FL_EXPR) 4827 continue; 4828 4829 if (hist_data->fields[i]->flags & HIST_FIELD_FL_HEX) { 4830 seq_printf(m, " %s: %10llx", field_name, 4831 tracing_map_read_sum(elt, i)); 4832 } else { 4833 seq_printf(m, " %s: %10llu", field_name, 4834 tracing_map_read_sum(elt, i)); 4835 } 4836 } 4837 4838 print_actions(m, hist_data, elt); 4839 4840 seq_puts(m, "\n"); 4841 } 4842 4843 static int print_entries(struct seq_file *m, 4844 struct hist_trigger_data *hist_data) 4845 { 4846 struct tracing_map_sort_entry **sort_entries = NULL; 4847 struct tracing_map *map = hist_data->map; 4848 int i, n_entries; 4849 4850 n_entries = tracing_map_sort_entries(map, hist_data->sort_keys, 4851 hist_data->n_sort_keys, 4852 &sort_entries); 4853 if (n_entries < 0) 4854 return n_entries; 4855 4856 for (i = 0; i < n_entries; i++) 4857 hist_trigger_entry_print(m, hist_data, 4858 sort_entries[i]->key, 4859 sort_entries[i]->elt); 4860 4861 tracing_map_destroy_sort_entries(sort_entries, n_entries); 4862 4863 return n_entries; 4864 } 4865 4866 static void hist_trigger_show(struct seq_file *m, 4867 struct event_trigger_data *data, int n) 4868 { 4869 struct hist_trigger_data *hist_data; 4870 int n_entries; 4871 4872 if (n > 0) 4873 seq_puts(m, "\n\n"); 4874 4875 seq_puts(m, "# event histogram\n#\n# trigger info: "); 4876 data->ops->print(m, data->ops, data); 4877 seq_puts(m, "#\n\n"); 4878 4879 hist_data = data->private_data; 4880 n_entries = print_entries(m, hist_data); 4881 if (n_entries < 0) 4882 n_entries = 0; 4883 4884 track_data_snapshot_print(m, hist_data); 4885 4886 seq_printf(m, "\nTotals:\n Hits: %llu\n Entries: %u\n Dropped: %llu\n", 4887 (u64)atomic64_read(&hist_data->map->hits), 4888 n_entries, (u64)atomic64_read(&hist_data->map->drops)); 4889 } 4890 4891 static int hist_show(struct seq_file *m, void *v) 4892 { 4893 struct event_trigger_data *data; 4894 struct trace_event_file *event_file; 4895 int n = 0, ret = 0; 4896 4897 mutex_lock(&event_mutex); 4898 4899 event_file = event_file_data(m->private); 4900 if (unlikely(!event_file)) { 4901 ret = -ENODEV; 4902 goto out_unlock; 4903 } 4904 4905 list_for_each_entry(data, &event_file->triggers, list) { 4906 if (data->cmd_ops->trigger_type == ETT_EVENT_HIST) 4907 hist_trigger_show(m, data, n++); 4908 } 4909 4910 out_unlock: 4911 mutex_unlock(&event_mutex); 4912 4913 return ret; 4914 } 4915 4916 static int event_hist_open(struct inode *inode, struct file *file) 4917 { 4918 int ret; 4919 4920 ret = security_locked_down(LOCKDOWN_TRACEFS); 4921 if (ret) 4922 return ret; 4923 4924 return single_open(file, hist_show, file); 4925 } 4926 4927 const struct file_operations event_hist_fops = { 4928 .open = event_hist_open, 4929 .read = seq_read, 4930 .llseek = seq_lseek, 4931 .release = single_release, 4932 }; 4933 4934 #ifdef CONFIG_HIST_TRIGGERS_DEBUG 4935 static void hist_field_debug_show_flags(struct seq_file *m, 4936 unsigned long flags) 4937 { 4938 seq_puts(m, " flags:\n"); 4939 4940 if (flags & HIST_FIELD_FL_KEY) 4941 seq_puts(m, " HIST_FIELD_FL_KEY\n"); 4942 else if (flags & HIST_FIELD_FL_HITCOUNT) 4943 seq_puts(m, " VAL: HIST_FIELD_FL_HITCOUNT\n"); 4944 else if (flags & HIST_FIELD_FL_VAR) 4945 seq_puts(m, " HIST_FIELD_FL_VAR\n"); 4946 else if (flags & HIST_FIELD_FL_VAR_REF) 4947 seq_puts(m, " HIST_FIELD_FL_VAR_REF\n"); 4948 else 4949 seq_puts(m, " VAL: normal u64 value\n"); 4950 4951 if (flags & HIST_FIELD_FL_ALIAS) 4952 seq_puts(m, " HIST_FIELD_FL_ALIAS\n"); 4953 } 4954 4955 static int hist_field_debug_show(struct seq_file *m, 4956 struct hist_field *field, unsigned long flags) 4957 { 4958 if ((field->flags & flags) != flags) { 4959 seq_printf(m, "ERROR: bad flags - %lx\n", flags); 4960 return -EINVAL; 4961 } 4962 4963 hist_field_debug_show_flags(m, field->flags); 4964 if (field->field) 4965 seq_printf(m, " ftrace_event_field name: %s\n", 4966 field->field->name); 4967 4968 if (field->flags & HIST_FIELD_FL_VAR) { 4969 seq_printf(m, " var.name: %s\n", field->var.name); 4970 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n", 4971 field->var.idx); 4972 } 4973 4974 if (field->flags & HIST_FIELD_FL_ALIAS) 4975 seq_printf(m, " var_ref_idx (into hist_data->var_refs[]): %u\n", 4976 field->var_ref_idx); 4977 4978 if (field->flags & HIST_FIELD_FL_VAR_REF) { 4979 seq_printf(m, " name: %s\n", field->name); 4980 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n", 4981 field->var.idx); 4982 seq_printf(m, " var.hist_data: %p\n", field->var.hist_data); 4983 seq_printf(m, " var_ref_idx (into hist_data->var_refs[]): %u\n", 4984 field->var_ref_idx); 4985 if (field->system) 4986 seq_printf(m, " system: %s\n", field->system); 4987 if (field->event_name) 4988 seq_printf(m, " event_name: %s\n", field->event_name); 4989 } 4990 4991 seq_printf(m, " type: %s\n", field->type); 4992 seq_printf(m, " size: %u\n", field->size); 4993 seq_printf(m, " is_signed: %u\n", field->is_signed); 4994 4995 return 0; 4996 } 4997 4998 static int field_var_debug_show(struct seq_file *m, 4999 struct field_var *field_var, unsigned int i, 5000 bool save_vars) 5001 { 5002 const char *vars_name = save_vars ? "save_vars" : "field_vars"; 5003 struct hist_field *field; 5004 int ret = 0; 5005 5006 seq_printf(m, "\n hist_data->%s[%d]:\n", vars_name, i); 5007 5008 field = field_var->var; 5009 5010 seq_printf(m, "\n %s[%d].var:\n", vars_name, i); 5011 5012 hist_field_debug_show_flags(m, field->flags); 5013 seq_printf(m, " var.name: %s\n", field->var.name); 5014 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n", 5015 field->var.idx); 5016 5017 field = field_var->val; 5018 5019 seq_printf(m, "\n %s[%d].val:\n", vars_name, i); 5020 if (field->field) 5021 seq_printf(m, " ftrace_event_field name: %s\n", 5022 field->field->name); 5023 else { 5024 ret = -EINVAL; 5025 goto out; 5026 } 5027 5028 seq_printf(m, " type: %s\n", field->type); 5029 seq_printf(m, " size: %u\n", field->size); 5030 seq_printf(m, " is_signed: %u\n", field->is_signed); 5031 out: 5032 return ret; 5033 } 5034 5035 static int hist_action_debug_show(struct seq_file *m, 5036 struct action_data *data, int i) 5037 { 5038 int ret = 0; 5039 5040 if (data->handler == HANDLER_ONMAX || 5041 data->handler == HANDLER_ONCHANGE) { 5042 seq_printf(m, "\n hist_data->actions[%d].track_data.var_ref:\n", i); 5043 ret = hist_field_debug_show(m, data->track_data.var_ref, 5044 HIST_FIELD_FL_VAR_REF); 5045 if (ret) 5046 goto out; 5047 5048 seq_printf(m, "\n hist_data->actions[%d].track_data.track_var:\n", i); 5049 ret = hist_field_debug_show(m, data->track_data.track_var, 5050 HIST_FIELD_FL_VAR); 5051 if (ret) 5052 goto out; 5053 } 5054 5055 if (data->handler == HANDLER_ONMATCH) { 5056 seq_printf(m, "\n hist_data->actions[%d].match_data.event_system: %s\n", 5057 i, data->match_data.event_system); 5058 seq_printf(m, " hist_data->actions[%d].match_data.event: %s\n", 5059 i, data->match_data.event); 5060 } 5061 out: 5062 return ret; 5063 } 5064 5065 static int hist_actions_debug_show(struct seq_file *m, 5066 struct hist_trigger_data *hist_data) 5067 { 5068 int i, ret = 0; 5069 5070 if (hist_data->n_actions) 5071 seq_puts(m, "\n action tracking variables (for onmax()/onchange()/onmatch()):\n"); 5072 5073 for (i = 0; i < hist_data->n_actions; i++) { 5074 struct action_data *action = hist_data->actions[i]; 5075 5076 ret = hist_action_debug_show(m, action, i); 5077 if (ret) 5078 goto out; 5079 } 5080 5081 if (hist_data->n_save_vars) 5082 seq_puts(m, "\n save action variables (save() params):\n"); 5083 5084 for (i = 0; i < hist_data->n_save_vars; i++) { 5085 ret = field_var_debug_show(m, hist_data->save_vars[i], i, true); 5086 if (ret) 5087 goto out; 5088 } 5089 out: 5090 return ret; 5091 } 5092 5093 static void hist_trigger_debug_show(struct seq_file *m, 5094 struct event_trigger_data *data, int n) 5095 { 5096 struct hist_trigger_data *hist_data; 5097 int i, ret; 5098 5099 if (n > 0) 5100 seq_puts(m, "\n\n"); 5101 5102 seq_puts(m, "# event histogram\n#\n# trigger info: "); 5103 data->ops->print(m, data->ops, data); 5104 seq_puts(m, "#\n\n"); 5105 5106 hist_data = data->private_data; 5107 5108 seq_printf(m, "hist_data: %p\n\n", hist_data); 5109 seq_printf(m, " n_vals: %u\n", hist_data->n_vals); 5110 seq_printf(m, " n_keys: %u\n", hist_data->n_keys); 5111 seq_printf(m, " n_fields: %u\n", hist_data->n_fields); 5112 5113 seq_puts(m, "\n val fields:\n\n"); 5114 5115 seq_puts(m, " hist_data->fields[0]:\n"); 5116 ret = hist_field_debug_show(m, hist_data->fields[0], 5117 HIST_FIELD_FL_HITCOUNT); 5118 if (ret) 5119 return; 5120 5121 for (i = 1; i < hist_data->n_vals; i++) { 5122 seq_printf(m, "\n hist_data->fields[%d]:\n", i); 5123 ret = hist_field_debug_show(m, hist_data->fields[i], 0); 5124 if (ret) 5125 return; 5126 } 5127 5128 seq_puts(m, "\n key fields:\n"); 5129 5130 for (i = hist_data->n_vals; i < hist_data->n_fields; i++) { 5131 seq_printf(m, "\n hist_data->fields[%d]:\n", i); 5132 ret = hist_field_debug_show(m, hist_data->fields[i], 5133 HIST_FIELD_FL_KEY); 5134 if (ret) 5135 return; 5136 } 5137 5138 if (hist_data->n_var_refs) 5139 seq_puts(m, "\n variable reference fields:\n"); 5140 5141 for (i = 0; i < hist_data->n_var_refs; i++) { 5142 seq_printf(m, "\n hist_data->var_refs[%d]:\n", i); 5143 ret = hist_field_debug_show(m, hist_data->var_refs[i], 5144 HIST_FIELD_FL_VAR_REF); 5145 if (ret) 5146 return; 5147 } 5148 5149 if (hist_data->n_field_vars) 5150 seq_puts(m, "\n field variables:\n"); 5151 5152 for (i = 0; i < hist_data->n_field_vars; i++) { 5153 ret = field_var_debug_show(m, hist_data->field_vars[i], i, false); 5154 if (ret) 5155 return; 5156 } 5157 5158 ret = hist_actions_debug_show(m, hist_data); 5159 if (ret) 5160 return; 5161 } 5162 5163 static int hist_debug_show(struct seq_file *m, void *v) 5164 { 5165 struct event_trigger_data *data; 5166 struct trace_event_file *event_file; 5167 int n = 0, ret = 0; 5168 5169 mutex_lock(&event_mutex); 5170 5171 event_file = event_file_data(m->private); 5172 if (unlikely(!event_file)) { 5173 ret = -ENODEV; 5174 goto out_unlock; 5175 } 5176 5177 list_for_each_entry(data, &event_file->triggers, list) { 5178 if (data->cmd_ops->trigger_type == ETT_EVENT_HIST) 5179 hist_trigger_debug_show(m, data, n++); 5180 } 5181 5182 out_unlock: 5183 mutex_unlock(&event_mutex); 5184 5185 return ret; 5186 } 5187 5188 static int event_hist_debug_open(struct inode *inode, struct file *file) 5189 { 5190 int ret; 5191 5192 ret = security_locked_down(LOCKDOWN_TRACEFS); 5193 if (ret) 5194 return ret; 5195 5196 return single_open(file, hist_debug_show, file); 5197 } 5198 5199 const struct file_operations event_hist_debug_fops = { 5200 .open = event_hist_debug_open, 5201 .read = seq_read, 5202 .llseek = seq_lseek, 5203 .release = single_release, 5204 }; 5205 #endif 5206 5207 static void hist_field_print(struct seq_file *m, struct hist_field *hist_field) 5208 { 5209 const char *field_name = hist_field_name(hist_field, 0); 5210 5211 if (hist_field->var.name) 5212 seq_printf(m, "%s=", hist_field->var.name); 5213 5214 if (hist_field->flags & HIST_FIELD_FL_CPU) 5215 seq_puts(m, "common_cpu"); 5216 else if (field_name) { 5217 if (hist_field->flags & HIST_FIELD_FL_VAR_REF || 5218 hist_field->flags & HIST_FIELD_FL_ALIAS) 5219 seq_putc(m, '$'); 5220 seq_printf(m, "%s", field_name); 5221 } else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP) 5222 seq_puts(m, "common_timestamp"); 5223 5224 if (hist_field->flags) { 5225 if (!(hist_field->flags & HIST_FIELD_FL_VAR_REF) && 5226 !(hist_field->flags & HIST_FIELD_FL_EXPR)) { 5227 const char *flags = get_hist_field_flags(hist_field); 5228 5229 if (flags) 5230 seq_printf(m, ".%s", flags); 5231 } 5232 } 5233 if (hist_field->buckets) 5234 seq_printf(m, "=%ld", hist_field->buckets); 5235 } 5236 5237 static int event_hist_trigger_print(struct seq_file *m, 5238 struct event_trigger_ops *ops, 5239 struct event_trigger_data *data) 5240 { 5241 struct hist_trigger_data *hist_data = data->private_data; 5242 struct hist_field *field; 5243 bool have_var = false; 5244 unsigned int i; 5245 5246 seq_puts(m, "hist:"); 5247 5248 if (data->name) 5249 seq_printf(m, "%s:", data->name); 5250 5251 seq_puts(m, "keys="); 5252 5253 for_each_hist_key_field(i, hist_data) { 5254 field = hist_data->fields[i]; 5255 5256 if (i > hist_data->n_vals) 5257 seq_puts(m, ","); 5258 5259 if (field->flags & HIST_FIELD_FL_STACKTRACE) 5260 seq_puts(m, "stacktrace"); 5261 else 5262 hist_field_print(m, field); 5263 } 5264 5265 seq_puts(m, ":vals="); 5266 5267 for_each_hist_val_field(i, hist_data) { 5268 field = hist_data->fields[i]; 5269 if (field->flags & HIST_FIELD_FL_VAR) { 5270 have_var = true; 5271 continue; 5272 } 5273 5274 if (i == HITCOUNT_IDX) 5275 seq_puts(m, "hitcount"); 5276 else { 5277 seq_puts(m, ","); 5278 hist_field_print(m, field); 5279 } 5280 } 5281 5282 if (have_var) { 5283 unsigned int n = 0; 5284 5285 seq_puts(m, ":"); 5286 5287 for_each_hist_val_field(i, hist_data) { 5288 field = hist_data->fields[i]; 5289 5290 if (field->flags & HIST_FIELD_FL_VAR) { 5291 if (n++) 5292 seq_puts(m, ","); 5293 hist_field_print(m, field); 5294 } 5295 } 5296 } 5297 5298 seq_puts(m, ":sort="); 5299 5300 for (i = 0; i < hist_data->n_sort_keys; i++) { 5301 struct tracing_map_sort_key *sort_key; 5302 unsigned int idx, first_key_idx; 5303 5304 /* skip VAR vals */ 5305 first_key_idx = hist_data->n_vals - hist_data->n_vars; 5306 5307 sort_key = &hist_data->sort_keys[i]; 5308 idx = sort_key->field_idx; 5309 5310 if (WARN_ON(idx >= HIST_FIELDS_MAX)) 5311 return -EINVAL; 5312 5313 if (i > 0) 5314 seq_puts(m, ","); 5315 5316 if (idx == HITCOUNT_IDX) 5317 seq_puts(m, "hitcount"); 5318 else { 5319 if (idx >= first_key_idx) 5320 idx += hist_data->n_vars; 5321 hist_field_print(m, hist_data->fields[idx]); 5322 } 5323 5324 if (sort_key->descending) 5325 seq_puts(m, ".descending"); 5326 } 5327 seq_printf(m, ":size=%u", (1 << hist_data->map->map_bits)); 5328 if (hist_data->enable_timestamps) 5329 seq_printf(m, ":clock=%s", hist_data->attrs->clock); 5330 5331 print_actions_spec(m, hist_data); 5332 5333 if (data->filter_str) 5334 seq_printf(m, " if %s", data->filter_str); 5335 5336 if (data->paused) 5337 seq_puts(m, " [paused]"); 5338 else 5339 seq_puts(m, " [active]"); 5340 5341 seq_putc(m, '\n'); 5342 5343 return 0; 5344 } 5345 5346 static int event_hist_trigger_init(struct event_trigger_ops *ops, 5347 struct event_trigger_data *data) 5348 { 5349 struct hist_trigger_data *hist_data = data->private_data; 5350 5351 if (!data->ref && hist_data->attrs->name) 5352 save_named_trigger(hist_data->attrs->name, data); 5353 5354 data->ref++; 5355 5356 return 0; 5357 } 5358 5359 static void unregister_field_var_hists(struct hist_trigger_data *hist_data) 5360 { 5361 struct trace_event_file *file; 5362 unsigned int i; 5363 char *cmd; 5364 int ret; 5365 5366 for (i = 0; i < hist_data->n_field_var_hists; i++) { 5367 file = hist_data->field_var_hists[i]->hist_data->event_file; 5368 cmd = hist_data->field_var_hists[i]->cmd; 5369 ret = event_hist_trigger_func(&trigger_hist_cmd, file, 5370 "!hist", "hist", cmd); 5371 WARN_ON_ONCE(ret < 0); 5372 } 5373 } 5374 5375 static void event_hist_trigger_free(struct event_trigger_ops *ops, 5376 struct event_trigger_data *data) 5377 { 5378 struct hist_trigger_data *hist_data = data->private_data; 5379 5380 if (WARN_ON_ONCE(data->ref <= 0)) 5381 return; 5382 5383 data->ref--; 5384 if (!data->ref) { 5385 if (data->name) 5386 del_named_trigger(data); 5387 5388 trigger_data_free(data); 5389 5390 remove_hist_vars(hist_data); 5391 5392 unregister_field_var_hists(hist_data); 5393 5394 destroy_hist_data(hist_data); 5395 } 5396 } 5397 5398 static struct event_trigger_ops event_hist_trigger_ops = { 5399 .func = event_hist_trigger, 5400 .print = event_hist_trigger_print, 5401 .init = event_hist_trigger_init, 5402 .free = event_hist_trigger_free, 5403 }; 5404 5405 static int event_hist_trigger_named_init(struct event_trigger_ops *ops, 5406 struct event_trigger_data *data) 5407 { 5408 data->ref++; 5409 5410 save_named_trigger(data->named_data->name, data); 5411 5412 event_hist_trigger_init(ops, data->named_data); 5413 5414 return 0; 5415 } 5416 5417 static void event_hist_trigger_named_free(struct event_trigger_ops *ops, 5418 struct event_trigger_data *data) 5419 { 5420 if (WARN_ON_ONCE(data->ref <= 0)) 5421 return; 5422 5423 event_hist_trigger_free(ops, data->named_data); 5424 5425 data->ref--; 5426 if (!data->ref) { 5427 del_named_trigger(data); 5428 trigger_data_free(data); 5429 } 5430 } 5431 5432 static struct event_trigger_ops event_hist_trigger_named_ops = { 5433 .func = event_hist_trigger, 5434 .print = event_hist_trigger_print, 5435 .init = event_hist_trigger_named_init, 5436 .free = event_hist_trigger_named_free, 5437 }; 5438 5439 static struct event_trigger_ops *event_hist_get_trigger_ops(char *cmd, 5440 char *param) 5441 { 5442 return &event_hist_trigger_ops; 5443 } 5444 5445 static void hist_clear(struct event_trigger_data *data) 5446 { 5447 struct hist_trigger_data *hist_data = data->private_data; 5448 5449 if (data->name) 5450 pause_named_trigger(data); 5451 5452 tracepoint_synchronize_unregister(); 5453 5454 tracing_map_clear(hist_data->map); 5455 5456 if (data->name) 5457 unpause_named_trigger(data); 5458 } 5459 5460 static bool compatible_field(struct ftrace_event_field *field, 5461 struct ftrace_event_field *test_field) 5462 { 5463 if (field == test_field) 5464 return true; 5465 if (field == NULL || test_field == NULL) 5466 return false; 5467 if (strcmp(field->name, test_field->name) != 0) 5468 return false; 5469 if (strcmp(field->type, test_field->type) != 0) 5470 return false; 5471 if (field->size != test_field->size) 5472 return false; 5473 if (field->is_signed != test_field->is_signed) 5474 return false; 5475 5476 return true; 5477 } 5478 5479 static bool hist_trigger_match(struct event_trigger_data *data, 5480 struct event_trigger_data *data_test, 5481 struct event_trigger_data *named_data, 5482 bool ignore_filter) 5483 { 5484 struct tracing_map_sort_key *sort_key, *sort_key_test; 5485 struct hist_trigger_data *hist_data, *hist_data_test; 5486 struct hist_field *key_field, *key_field_test; 5487 unsigned int i; 5488 5489 if (named_data && (named_data != data_test) && 5490 (named_data != data_test->named_data)) 5491 return false; 5492 5493 if (!named_data && is_named_trigger(data_test)) 5494 return false; 5495 5496 hist_data = data->private_data; 5497 hist_data_test = data_test->private_data; 5498 5499 if (hist_data->n_vals != hist_data_test->n_vals || 5500 hist_data->n_fields != hist_data_test->n_fields || 5501 hist_data->n_sort_keys != hist_data_test->n_sort_keys) 5502 return false; 5503 5504 if (!ignore_filter) { 5505 if ((data->filter_str && !data_test->filter_str) || 5506 (!data->filter_str && data_test->filter_str)) 5507 return false; 5508 } 5509 5510 for_each_hist_field(i, hist_data) { 5511 key_field = hist_data->fields[i]; 5512 key_field_test = hist_data_test->fields[i]; 5513 5514 if (key_field->flags != key_field_test->flags) 5515 return false; 5516 if (!compatible_field(key_field->field, key_field_test->field)) 5517 return false; 5518 if (key_field->offset != key_field_test->offset) 5519 return false; 5520 if (key_field->size != key_field_test->size) 5521 return false; 5522 if (key_field->is_signed != key_field_test->is_signed) 5523 return false; 5524 if (!!key_field->var.name != !!key_field_test->var.name) 5525 return false; 5526 if (key_field->var.name && 5527 strcmp(key_field->var.name, key_field_test->var.name) != 0) 5528 return false; 5529 } 5530 5531 for (i = 0; i < hist_data->n_sort_keys; i++) { 5532 sort_key = &hist_data->sort_keys[i]; 5533 sort_key_test = &hist_data_test->sort_keys[i]; 5534 5535 if (sort_key->field_idx != sort_key_test->field_idx || 5536 sort_key->descending != sort_key_test->descending) 5537 return false; 5538 } 5539 5540 if (!ignore_filter && data->filter_str && 5541 (strcmp(data->filter_str, data_test->filter_str) != 0)) 5542 return false; 5543 5544 if (!actions_match(hist_data, hist_data_test)) 5545 return false; 5546 5547 return true; 5548 } 5549 5550 static int hist_register_trigger(char *glob, struct event_trigger_ops *ops, 5551 struct event_trigger_data *data, 5552 struct trace_event_file *file) 5553 { 5554 struct hist_trigger_data *hist_data = data->private_data; 5555 struct event_trigger_data *test, *named_data = NULL; 5556 struct trace_array *tr = file->tr; 5557 int ret = 0; 5558 5559 if (hist_data->attrs->name) { 5560 named_data = find_named_trigger(hist_data->attrs->name); 5561 if (named_data) { 5562 if (!hist_trigger_match(data, named_data, named_data, 5563 true)) { 5564 hist_err(tr, HIST_ERR_NAMED_MISMATCH, errpos(hist_data->attrs->name)); 5565 ret = -EINVAL; 5566 goto out; 5567 } 5568 } 5569 } 5570 5571 if (hist_data->attrs->name && !named_data) 5572 goto new; 5573 5574 lockdep_assert_held(&event_mutex); 5575 5576 list_for_each_entry(test, &file->triggers, list) { 5577 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 5578 if (!hist_trigger_match(data, test, named_data, false)) 5579 continue; 5580 if (hist_data->attrs->pause) 5581 test->paused = true; 5582 else if (hist_data->attrs->cont) 5583 test->paused = false; 5584 else if (hist_data->attrs->clear) 5585 hist_clear(test); 5586 else { 5587 hist_err(tr, HIST_ERR_TRIGGER_EEXIST, 0); 5588 ret = -EEXIST; 5589 } 5590 goto out; 5591 } 5592 } 5593 new: 5594 if (hist_data->attrs->cont || hist_data->attrs->clear) { 5595 hist_err(tr, HIST_ERR_TRIGGER_ENOENT_CLEAR, 0); 5596 ret = -ENOENT; 5597 goto out; 5598 } 5599 5600 if (hist_data->attrs->pause) 5601 data->paused = true; 5602 5603 if (named_data) { 5604 data->private_data = named_data->private_data; 5605 set_named_trigger_data(data, named_data); 5606 data->ops = &event_hist_trigger_named_ops; 5607 } 5608 5609 if (data->ops->init) { 5610 ret = data->ops->init(data->ops, data); 5611 if (ret < 0) 5612 goto out; 5613 } 5614 5615 if (hist_data->enable_timestamps) { 5616 char *clock = hist_data->attrs->clock; 5617 5618 ret = tracing_set_clock(file->tr, hist_data->attrs->clock); 5619 if (ret) { 5620 hist_err(tr, HIST_ERR_SET_CLOCK_FAIL, errpos(clock)); 5621 goto out; 5622 } 5623 5624 tracing_set_filter_buffering(file->tr, true); 5625 } 5626 5627 if (named_data) 5628 destroy_hist_data(hist_data); 5629 5630 ret++; 5631 out: 5632 return ret; 5633 } 5634 5635 static int hist_trigger_enable(struct event_trigger_data *data, 5636 struct trace_event_file *file) 5637 { 5638 int ret = 0; 5639 5640 list_add_tail_rcu(&data->list, &file->triggers); 5641 5642 update_cond_flag(file); 5643 5644 if (trace_event_trigger_enable_disable(file, 1) < 0) { 5645 list_del_rcu(&data->list); 5646 update_cond_flag(file); 5647 ret--; 5648 } 5649 5650 return ret; 5651 } 5652 5653 static bool have_hist_trigger_match(struct event_trigger_data *data, 5654 struct trace_event_file *file) 5655 { 5656 struct hist_trigger_data *hist_data = data->private_data; 5657 struct event_trigger_data *test, *named_data = NULL; 5658 bool match = false; 5659 5660 lockdep_assert_held(&event_mutex); 5661 5662 if (hist_data->attrs->name) 5663 named_data = find_named_trigger(hist_data->attrs->name); 5664 5665 list_for_each_entry(test, &file->triggers, list) { 5666 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 5667 if (hist_trigger_match(data, test, named_data, false)) { 5668 match = true; 5669 break; 5670 } 5671 } 5672 } 5673 5674 return match; 5675 } 5676 5677 static bool hist_trigger_check_refs(struct event_trigger_data *data, 5678 struct trace_event_file *file) 5679 { 5680 struct hist_trigger_data *hist_data = data->private_data; 5681 struct event_trigger_data *test, *named_data = NULL; 5682 5683 lockdep_assert_held(&event_mutex); 5684 5685 if (hist_data->attrs->name) 5686 named_data = find_named_trigger(hist_data->attrs->name); 5687 5688 list_for_each_entry(test, &file->triggers, list) { 5689 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 5690 if (!hist_trigger_match(data, test, named_data, false)) 5691 continue; 5692 hist_data = test->private_data; 5693 if (check_var_refs(hist_data)) 5694 return true; 5695 break; 5696 } 5697 } 5698 5699 return false; 5700 } 5701 5702 static void hist_unregister_trigger(char *glob, struct event_trigger_ops *ops, 5703 struct event_trigger_data *data, 5704 struct trace_event_file *file) 5705 { 5706 struct hist_trigger_data *hist_data = data->private_data; 5707 struct event_trigger_data *test, *named_data = NULL; 5708 bool unregistered = false; 5709 5710 lockdep_assert_held(&event_mutex); 5711 5712 if (hist_data->attrs->name) 5713 named_data = find_named_trigger(hist_data->attrs->name); 5714 5715 list_for_each_entry(test, &file->triggers, list) { 5716 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 5717 if (!hist_trigger_match(data, test, named_data, false)) 5718 continue; 5719 unregistered = true; 5720 list_del_rcu(&test->list); 5721 trace_event_trigger_enable_disable(file, 0); 5722 update_cond_flag(file); 5723 break; 5724 } 5725 } 5726 5727 if (unregistered && test->ops->free) 5728 test->ops->free(test->ops, test); 5729 5730 if (hist_data->enable_timestamps) { 5731 if (!hist_data->remove || unregistered) 5732 tracing_set_filter_buffering(file->tr, false); 5733 } 5734 } 5735 5736 static bool hist_file_check_refs(struct trace_event_file *file) 5737 { 5738 struct hist_trigger_data *hist_data; 5739 struct event_trigger_data *test; 5740 5741 lockdep_assert_held(&event_mutex); 5742 5743 list_for_each_entry(test, &file->triggers, list) { 5744 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 5745 hist_data = test->private_data; 5746 if (check_var_refs(hist_data)) 5747 return true; 5748 } 5749 } 5750 5751 return false; 5752 } 5753 5754 static void hist_unreg_all(struct trace_event_file *file) 5755 { 5756 struct event_trigger_data *test, *n; 5757 struct hist_trigger_data *hist_data; 5758 struct synth_event *se; 5759 const char *se_name; 5760 5761 lockdep_assert_held(&event_mutex); 5762 5763 if (hist_file_check_refs(file)) 5764 return; 5765 5766 list_for_each_entry_safe(test, n, &file->triggers, list) { 5767 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 5768 hist_data = test->private_data; 5769 list_del_rcu(&test->list); 5770 trace_event_trigger_enable_disable(file, 0); 5771 5772 se_name = trace_event_name(file->event_call); 5773 se = find_synth_event(se_name); 5774 if (se) 5775 se->ref--; 5776 5777 update_cond_flag(file); 5778 if (hist_data->enable_timestamps) 5779 tracing_set_filter_buffering(file->tr, false); 5780 if (test->ops->free) 5781 test->ops->free(test->ops, test); 5782 } 5783 } 5784 } 5785 5786 static int event_hist_trigger_func(struct event_command *cmd_ops, 5787 struct trace_event_file *file, 5788 char *glob, char *cmd, char *param) 5789 { 5790 unsigned int hist_trigger_bits = TRACING_MAP_BITS_DEFAULT; 5791 struct event_trigger_data *trigger_data; 5792 struct hist_trigger_attrs *attrs; 5793 struct event_trigger_ops *trigger_ops; 5794 struct hist_trigger_data *hist_data; 5795 struct synth_event *se; 5796 const char *se_name; 5797 bool remove = false; 5798 char *trigger, *p; 5799 int ret = 0; 5800 5801 lockdep_assert_held(&event_mutex); 5802 5803 if (glob && strlen(glob)) { 5804 hist_err_clear(); 5805 last_cmd_set(file, param); 5806 } 5807 5808 if (!param) 5809 return -EINVAL; 5810 5811 if (glob[0] == '!') 5812 remove = true; 5813 5814 /* 5815 * separate the trigger from the filter (k:v [if filter]) 5816 * allowing for whitespace in the trigger 5817 */ 5818 p = trigger = param; 5819 do { 5820 p = strstr(p, "if"); 5821 if (!p) 5822 break; 5823 if (p == param) 5824 return -EINVAL; 5825 if (*(p - 1) != ' ' && *(p - 1) != '\t') { 5826 p++; 5827 continue; 5828 } 5829 if (p >= param + strlen(param) - (sizeof("if") - 1) - 1) 5830 return -EINVAL; 5831 if (*(p + sizeof("if") - 1) != ' ' && *(p + sizeof("if") - 1) != '\t') { 5832 p++; 5833 continue; 5834 } 5835 break; 5836 } while (p); 5837 5838 if (!p) 5839 param = NULL; 5840 else { 5841 *(p - 1) = '\0'; 5842 param = strstrip(p); 5843 trigger = strstrip(trigger); 5844 } 5845 5846 attrs = parse_hist_trigger_attrs(file->tr, trigger); 5847 if (IS_ERR(attrs)) 5848 return PTR_ERR(attrs); 5849 5850 if (attrs->map_bits) 5851 hist_trigger_bits = attrs->map_bits; 5852 5853 hist_data = create_hist_data(hist_trigger_bits, attrs, file, remove); 5854 if (IS_ERR(hist_data)) { 5855 destroy_hist_trigger_attrs(attrs); 5856 return PTR_ERR(hist_data); 5857 } 5858 5859 trigger_ops = cmd_ops->get_trigger_ops(cmd, trigger); 5860 5861 trigger_data = kzalloc(sizeof(*trigger_data), GFP_KERNEL); 5862 if (!trigger_data) { 5863 ret = -ENOMEM; 5864 goto out_free; 5865 } 5866 5867 trigger_data->count = -1; 5868 trigger_data->ops = trigger_ops; 5869 trigger_data->cmd_ops = cmd_ops; 5870 5871 INIT_LIST_HEAD(&trigger_data->list); 5872 RCU_INIT_POINTER(trigger_data->filter, NULL); 5873 5874 trigger_data->private_data = hist_data; 5875 5876 /* if param is non-empty, it's supposed to be a filter */ 5877 if (param && cmd_ops->set_filter) { 5878 ret = cmd_ops->set_filter(param, trigger_data, file); 5879 if (ret < 0) 5880 goto out_free; 5881 } 5882 5883 if (remove) { 5884 if (!have_hist_trigger_match(trigger_data, file)) 5885 goto out_free; 5886 5887 if (hist_trigger_check_refs(trigger_data, file)) { 5888 ret = -EBUSY; 5889 goto out_free; 5890 } 5891 5892 cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file); 5893 se_name = trace_event_name(file->event_call); 5894 se = find_synth_event(se_name); 5895 if (se) 5896 se->ref--; 5897 ret = 0; 5898 goto out_free; 5899 } 5900 5901 ret = cmd_ops->reg(glob, trigger_ops, trigger_data, file); 5902 /* 5903 * The above returns on success the # of triggers registered, 5904 * but if it didn't register any it returns zero. Consider no 5905 * triggers registered a failure too. 5906 */ 5907 if (!ret) { 5908 if (!(attrs->pause || attrs->cont || attrs->clear)) 5909 ret = -ENOENT; 5910 goto out_free; 5911 } else if (ret < 0) 5912 goto out_free; 5913 5914 if (get_named_trigger_data(trigger_data)) 5915 goto enable; 5916 5917 if (has_hist_vars(hist_data)) 5918 save_hist_vars(hist_data); 5919 5920 ret = create_actions(hist_data); 5921 if (ret) 5922 goto out_unreg; 5923 5924 ret = tracing_map_init(hist_data->map); 5925 if (ret) 5926 goto out_unreg; 5927 enable: 5928 ret = hist_trigger_enable(trigger_data, file); 5929 if (ret) 5930 goto out_unreg; 5931 5932 se_name = trace_event_name(file->event_call); 5933 se = find_synth_event(se_name); 5934 if (se) 5935 se->ref++; 5936 /* Just return zero, not the number of registered triggers */ 5937 ret = 0; 5938 out: 5939 if (ret == 0) 5940 hist_err_clear(); 5941 5942 return ret; 5943 out_unreg: 5944 cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file); 5945 out_free: 5946 if (cmd_ops->set_filter) 5947 cmd_ops->set_filter(NULL, trigger_data, NULL); 5948 5949 remove_hist_vars(hist_data); 5950 5951 kfree(trigger_data); 5952 5953 destroy_hist_data(hist_data); 5954 goto out; 5955 } 5956 5957 static struct event_command trigger_hist_cmd = { 5958 .name = "hist", 5959 .trigger_type = ETT_EVENT_HIST, 5960 .flags = EVENT_CMD_FL_NEEDS_REC, 5961 .func = event_hist_trigger_func, 5962 .reg = hist_register_trigger, 5963 .unreg = hist_unregister_trigger, 5964 .unreg_all = hist_unreg_all, 5965 .get_trigger_ops = event_hist_get_trigger_ops, 5966 .set_filter = set_trigger_filter, 5967 }; 5968 5969 __init int register_trigger_hist_cmd(void) 5970 { 5971 int ret; 5972 5973 ret = register_event_command(&trigger_hist_cmd); 5974 WARN_ON(ret < 0); 5975 5976 return ret; 5977 } 5978 5979 static void 5980 hist_enable_trigger(struct event_trigger_data *data, 5981 struct trace_buffer *buffer, void *rec, 5982 struct ring_buffer_event *event) 5983 { 5984 struct enable_trigger_data *enable_data = data->private_data; 5985 struct event_trigger_data *test; 5986 5987 list_for_each_entry_rcu(test, &enable_data->file->triggers, list, 5988 lockdep_is_held(&event_mutex)) { 5989 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 5990 if (enable_data->enable) 5991 test->paused = false; 5992 else 5993 test->paused = true; 5994 } 5995 } 5996 } 5997 5998 static void 5999 hist_enable_count_trigger(struct event_trigger_data *data, 6000 struct trace_buffer *buffer, void *rec, 6001 struct ring_buffer_event *event) 6002 { 6003 if (!data->count) 6004 return; 6005 6006 if (data->count != -1) 6007 (data->count)--; 6008 6009 hist_enable_trigger(data, buffer, rec, event); 6010 } 6011 6012 static struct event_trigger_ops hist_enable_trigger_ops = { 6013 .func = hist_enable_trigger, 6014 .print = event_enable_trigger_print, 6015 .init = event_trigger_init, 6016 .free = event_enable_trigger_free, 6017 }; 6018 6019 static struct event_trigger_ops hist_enable_count_trigger_ops = { 6020 .func = hist_enable_count_trigger, 6021 .print = event_enable_trigger_print, 6022 .init = event_trigger_init, 6023 .free = event_enable_trigger_free, 6024 }; 6025 6026 static struct event_trigger_ops hist_disable_trigger_ops = { 6027 .func = hist_enable_trigger, 6028 .print = event_enable_trigger_print, 6029 .init = event_trigger_init, 6030 .free = event_enable_trigger_free, 6031 }; 6032 6033 static struct event_trigger_ops hist_disable_count_trigger_ops = { 6034 .func = hist_enable_count_trigger, 6035 .print = event_enable_trigger_print, 6036 .init = event_trigger_init, 6037 .free = event_enable_trigger_free, 6038 }; 6039 6040 static struct event_trigger_ops * 6041 hist_enable_get_trigger_ops(char *cmd, char *param) 6042 { 6043 struct event_trigger_ops *ops; 6044 bool enable; 6045 6046 enable = (strcmp(cmd, ENABLE_HIST_STR) == 0); 6047 6048 if (enable) 6049 ops = param ? &hist_enable_count_trigger_ops : 6050 &hist_enable_trigger_ops; 6051 else 6052 ops = param ? &hist_disable_count_trigger_ops : 6053 &hist_disable_trigger_ops; 6054 6055 return ops; 6056 } 6057 6058 static void hist_enable_unreg_all(struct trace_event_file *file) 6059 { 6060 struct event_trigger_data *test, *n; 6061 6062 list_for_each_entry_safe(test, n, &file->triggers, list) { 6063 if (test->cmd_ops->trigger_type == ETT_HIST_ENABLE) { 6064 list_del_rcu(&test->list); 6065 update_cond_flag(file); 6066 trace_event_trigger_enable_disable(file, 0); 6067 if (test->ops->free) 6068 test->ops->free(test->ops, test); 6069 } 6070 } 6071 } 6072 6073 static struct event_command trigger_hist_enable_cmd = { 6074 .name = ENABLE_HIST_STR, 6075 .trigger_type = ETT_HIST_ENABLE, 6076 .func = event_enable_trigger_func, 6077 .reg = event_enable_register_trigger, 6078 .unreg = event_enable_unregister_trigger, 6079 .unreg_all = hist_enable_unreg_all, 6080 .get_trigger_ops = hist_enable_get_trigger_ops, 6081 .set_filter = set_trigger_filter, 6082 }; 6083 6084 static struct event_command trigger_hist_disable_cmd = { 6085 .name = DISABLE_HIST_STR, 6086 .trigger_type = ETT_HIST_ENABLE, 6087 .func = event_enable_trigger_func, 6088 .reg = event_enable_register_trigger, 6089 .unreg = event_enable_unregister_trigger, 6090 .unreg_all = hist_enable_unreg_all, 6091 .get_trigger_ops = hist_enable_get_trigger_ops, 6092 .set_filter = set_trigger_filter, 6093 }; 6094 6095 static __init void unregister_trigger_hist_enable_disable_cmds(void) 6096 { 6097 unregister_event_command(&trigger_hist_enable_cmd); 6098 unregister_event_command(&trigger_hist_disable_cmd); 6099 } 6100 6101 __init int register_trigger_hist_enable_disable_cmds(void) 6102 { 6103 int ret; 6104 6105 ret = register_event_command(&trigger_hist_enable_cmd); 6106 if (WARN_ON(ret < 0)) 6107 return ret; 6108 ret = register_event_command(&trigger_hist_disable_cmd); 6109 if (WARN_ON(ret < 0)) 6110 unregister_trigger_hist_enable_disable_cmds(); 6111 6112 return ret; 6113 } 6114