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.h" 23 #include "trace_dynevent.h" 24 25 #define SYNTH_SYSTEM "synthetic" 26 #define SYNTH_FIELDS_MAX 32 27 28 #define STR_VAR_LEN_MAX 32 /* must be multiple of sizeof(u64) */ 29 30 #define ERRORS \ 31 C(NONE, "No error"), \ 32 C(DUPLICATE_VAR, "Variable already defined"), \ 33 C(VAR_NOT_UNIQUE, "Variable name not unique, need to use fully qualified name (subsys.event.var) for variable"), \ 34 C(TOO_MANY_VARS, "Too many variables defined"), \ 35 C(MALFORMED_ASSIGNMENT, "Malformed assignment"), \ 36 C(NAMED_MISMATCH, "Named hist trigger doesn't match existing named trigger (includes variables)"), \ 37 C(TRIGGER_EEXIST, "Hist trigger already exists"), \ 38 C(TRIGGER_ENOENT_CLEAR, "Can't clear or continue a nonexistent hist trigger"), \ 39 C(SET_CLOCK_FAIL, "Couldn't set trace_clock"), \ 40 C(BAD_FIELD_MODIFIER, "Invalid field modifier"), \ 41 C(TOO_MANY_SUBEXPR, "Too many subexpressions (3 max)"), \ 42 C(TIMESTAMP_MISMATCH, "Timestamp units in expression don't match"), \ 43 C(TOO_MANY_FIELD_VARS, "Too many field variables defined"), \ 44 C(EVENT_FILE_NOT_FOUND, "Event file not found"), \ 45 C(HIST_NOT_FOUND, "Matching event histogram not found"), \ 46 C(HIST_CREATE_FAIL, "Couldn't create histogram for field"), \ 47 C(SYNTH_VAR_NOT_FOUND, "Couldn't find synthetic variable"), \ 48 C(SYNTH_EVENT_NOT_FOUND,"Couldn't find synthetic event"), \ 49 C(SYNTH_TYPE_MISMATCH, "Param type doesn't match synthetic event field type"), \ 50 C(SYNTH_COUNT_MISMATCH, "Param count doesn't match synthetic event field count"), \ 51 C(FIELD_VAR_PARSE_FAIL, "Couldn't parse field variable"), \ 52 C(VAR_CREATE_FIND_FAIL, "Couldn't create or find variable"), \ 53 C(ONX_NOT_VAR, "For onmax(x) or onchange(x), x must be a variable"), \ 54 C(ONX_VAR_NOT_FOUND, "Couldn't find onmax or onchange variable"), \ 55 C(ONX_VAR_CREATE_FAIL, "Couldn't create onmax or onchange variable"), \ 56 C(FIELD_VAR_CREATE_FAIL,"Couldn't create field variable"), \ 57 C(TOO_MANY_PARAMS, "Too many action params"), \ 58 C(PARAM_NOT_FOUND, "Couldn't find param"), \ 59 C(INVALID_PARAM, "Invalid action param"), \ 60 C(ACTION_NOT_FOUND, "No action found"), \ 61 C(NO_SAVE_PARAMS, "No params found for save()"), \ 62 C(TOO_MANY_SAVE_ACTIONS,"Can't have more than one save() action per hist"), \ 63 C(ACTION_MISMATCH, "Handler doesn't support action"), \ 64 C(NO_CLOSING_PAREN, "No closing paren found"), \ 65 C(SUBSYS_NOT_FOUND, "Missing subsystem"), \ 66 C(INVALID_SUBSYS_EVENT, "Invalid subsystem or event name"), \ 67 C(INVALID_REF_KEY, "Using variable references in keys not supported"), \ 68 C(VAR_NOT_FOUND, "Couldn't find variable"), \ 69 C(FIELD_NOT_FOUND, "Couldn't find field"), \ 70 C(EMPTY_ASSIGNMENT, "Empty assignment"), \ 71 C(INVALID_SORT_MODIFIER,"Invalid sort modifier"), \ 72 C(EMPTY_SORT_FIELD, "Empty sort field"), \ 73 C(TOO_MANY_SORT_FIELDS, "Too many sort fields (Max = 2)"), \ 74 C(INVALID_SORT_FIELD, "Sort field must be a key or a val"), 75 76 #undef C 77 #define C(a, b) HIST_ERR_##a 78 79 enum { ERRORS }; 80 81 #undef C 82 #define C(a, b) b 83 84 static const char *err_text[] = { ERRORS }; 85 86 struct hist_field; 87 88 typedef u64 (*hist_field_fn_t) (struct hist_field *field, 89 struct tracing_map_elt *elt, 90 struct ring_buffer_event *rbe, 91 void *event); 92 93 #define HIST_FIELD_OPERANDS_MAX 2 94 #define HIST_FIELDS_MAX (TRACING_MAP_FIELDS_MAX + TRACING_MAP_VARS_MAX) 95 #define HIST_ACTIONS_MAX 8 96 97 enum field_op_id { 98 FIELD_OP_NONE, 99 FIELD_OP_PLUS, 100 FIELD_OP_MINUS, 101 FIELD_OP_UNARY_MINUS, 102 }; 103 104 /* 105 * A hist_var (histogram variable) contains variable information for 106 * hist_fields having the HIST_FIELD_FL_VAR or HIST_FIELD_FL_VAR_REF 107 * flag set. A hist_var has a variable name e.g. ts0, and is 108 * associated with a given histogram trigger, as specified by 109 * hist_data. The hist_var idx is the unique index assigned to the 110 * variable by the hist trigger's tracing_map. The idx is what is 111 * used to set a variable's value and, by a variable reference, to 112 * retrieve it. 113 */ 114 struct hist_var { 115 char *name; 116 struct hist_trigger_data *hist_data; 117 unsigned int idx; 118 }; 119 120 struct hist_field { 121 struct ftrace_event_field *field; 122 unsigned long flags; 123 hist_field_fn_t fn; 124 unsigned int size; 125 unsigned int offset; 126 unsigned int is_signed; 127 const char *type; 128 struct hist_field *operands[HIST_FIELD_OPERANDS_MAX]; 129 struct hist_trigger_data *hist_data; 130 131 /* 132 * Variable fields contain variable-specific info in var. 133 */ 134 struct hist_var var; 135 enum field_op_id operator; 136 char *system; 137 char *event_name; 138 139 /* 140 * The name field is used for EXPR and VAR_REF fields. VAR 141 * fields contain the variable name in var.name. 142 */ 143 char *name; 144 145 /* 146 * When a histogram trigger is hit, if it has any references 147 * to variables, the values of those variables are collected 148 * into a var_ref_vals array by resolve_var_refs(). The 149 * current value of each variable is read from the tracing_map 150 * using the hist field's hist_var.idx and entered into the 151 * var_ref_idx entry i.e. var_ref_vals[var_ref_idx]. 152 */ 153 unsigned int var_ref_idx; 154 bool read_once; 155 }; 156 157 static u64 hist_field_none(struct hist_field *field, 158 struct tracing_map_elt *elt, 159 struct ring_buffer_event *rbe, 160 void *event) 161 { 162 return 0; 163 } 164 165 static u64 hist_field_counter(struct hist_field *field, 166 struct tracing_map_elt *elt, 167 struct ring_buffer_event *rbe, 168 void *event) 169 { 170 return 1; 171 } 172 173 static u64 hist_field_string(struct hist_field *hist_field, 174 struct tracing_map_elt *elt, 175 struct ring_buffer_event *rbe, 176 void *event) 177 { 178 char *addr = (char *)(event + hist_field->field->offset); 179 180 return (u64)(unsigned long)addr; 181 } 182 183 static u64 hist_field_dynstring(struct hist_field *hist_field, 184 struct tracing_map_elt *elt, 185 struct ring_buffer_event *rbe, 186 void *event) 187 { 188 u32 str_item = *(u32 *)(event + hist_field->field->offset); 189 int str_loc = str_item & 0xffff; 190 char *addr = (char *)(event + str_loc); 191 192 return (u64)(unsigned long)addr; 193 } 194 195 static u64 hist_field_pstring(struct hist_field *hist_field, 196 struct tracing_map_elt *elt, 197 struct ring_buffer_event *rbe, 198 void *event) 199 { 200 char **addr = (char **)(event + hist_field->field->offset); 201 202 return (u64)(unsigned long)*addr; 203 } 204 205 static u64 hist_field_log2(struct hist_field *hist_field, 206 struct tracing_map_elt *elt, 207 struct ring_buffer_event *rbe, 208 void *event) 209 { 210 struct hist_field *operand = hist_field->operands[0]; 211 212 u64 val = operand->fn(operand, elt, rbe, event); 213 214 return (u64) ilog2(roundup_pow_of_two(val)); 215 } 216 217 static u64 hist_field_plus(struct hist_field *hist_field, 218 struct tracing_map_elt *elt, 219 struct ring_buffer_event *rbe, 220 void *event) 221 { 222 struct hist_field *operand1 = hist_field->operands[0]; 223 struct hist_field *operand2 = hist_field->operands[1]; 224 225 u64 val1 = operand1->fn(operand1, elt, rbe, event); 226 u64 val2 = operand2->fn(operand2, elt, rbe, event); 227 228 return val1 + val2; 229 } 230 231 static u64 hist_field_minus(struct hist_field *hist_field, 232 struct tracing_map_elt *elt, 233 struct ring_buffer_event *rbe, 234 void *event) 235 { 236 struct hist_field *operand1 = hist_field->operands[0]; 237 struct hist_field *operand2 = hist_field->operands[1]; 238 239 u64 val1 = operand1->fn(operand1, elt, rbe, event); 240 u64 val2 = operand2->fn(operand2, elt, rbe, event); 241 242 return val1 - val2; 243 } 244 245 static u64 hist_field_unary_minus(struct hist_field *hist_field, 246 struct tracing_map_elt *elt, 247 struct ring_buffer_event *rbe, 248 void *event) 249 { 250 struct hist_field *operand = hist_field->operands[0]; 251 252 s64 sval = (s64)operand->fn(operand, elt, rbe, event); 253 u64 val = (u64)-sval; 254 255 return val; 256 } 257 258 #define DEFINE_HIST_FIELD_FN(type) \ 259 static u64 hist_field_##type(struct hist_field *hist_field, \ 260 struct tracing_map_elt *elt, \ 261 struct ring_buffer_event *rbe, \ 262 void *event) \ 263 { \ 264 type *addr = (type *)(event + hist_field->field->offset); \ 265 \ 266 return (u64)(unsigned long)*addr; \ 267 } 268 269 DEFINE_HIST_FIELD_FN(s64); 270 DEFINE_HIST_FIELD_FN(u64); 271 DEFINE_HIST_FIELD_FN(s32); 272 DEFINE_HIST_FIELD_FN(u32); 273 DEFINE_HIST_FIELD_FN(s16); 274 DEFINE_HIST_FIELD_FN(u16); 275 DEFINE_HIST_FIELD_FN(s8); 276 DEFINE_HIST_FIELD_FN(u8); 277 278 #define for_each_hist_field(i, hist_data) \ 279 for ((i) = 0; (i) < (hist_data)->n_fields; (i)++) 280 281 #define for_each_hist_val_field(i, hist_data) \ 282 for ((i) = 0; (i) < (hist_data)->n_vals; (i)++) 283 284 #define for_each_hist_key_field(i, hist_data) \ 285 for ((i) = (hist_data)->n_vals; (i) < (hist_data)->n_fields; (i)++) 286 287 #define HIST_STACKTRACE_DEPTH 16 288 #define HIST_STACKTRACE_SIZE (HIST_STACKTRACE_DEPTH * sizeof(unsigned long)) 289 #define HIST_STACKTRACE_SKIP 5 290 291 #define HITCOUNT_IDX 0 292 #define HIST_KEY_SIZE_MAX (MAX_FILTER_STR_VAL + HIST_STACKTRACE_SIZE) 293 294 enum hist_field_flags { 295 HIST_FIELD_FL_HITCOUNT = 1 << 0, 296 HIST_FIELD_FL_KEY = 1 << 1, 297 HIST_FIELD_FL_STRING = 1 << 2, 298 HIST_FIELD_FL_HEX = 1 << 3, 299 HIST_FIELD_FL_SYM = 1 << 4, 300 HIST_FIELD_FL_SYM_OFFSET = 1 << 5, 301 HIST_FIELD_FL_EXECNAME = 1 << 6, 302 HIST_FIELD_FL_SYSCALL = 1 << 7, 303 HIST_FIELD_FL_STACKTRACE = 1 << 8, 304 HIST_FIELD_FL_LOG2 = 1 << 9, 305 HIST_FIELD_FL_TIMESTAMP = 1 << 10, 306 HIST_FIELD_FL_TIMESTAMP_USECS = 1 << 11, 307 HIST_FIELD_FL_VAR = 1 << 12, 308 HIST_FIELD_FL_EXPR = 1 << 13, 309 HIST_FIELD_FL_VAR_REF = 1 << 14, 310 HIST_FIELD_FL_CPU = 1 << 15, 311 HIST_FIELD_FL_ALIAS = 1 << 16, 312 }; 313 314 struct var_defs { 315 unsigned int n_vars; 316 char *name[TRACING_MAP_VARS_MAX]; 317 char *expr[TRACING_MAP_VARS_MAX]; 318 }; 319 320 struct hist_trigger_attrs { 321 char *keys_str; 322 char *vals_str; 323 char *sort_key_str; 324 char *name; 325 char *clock; 326 bool pause; 327 bool cont; 328 bool clear; 329 bool ts_in_usecs; 330 unsigned int map_bits; 331 332 char *assignment_str[TRACING_MAP_VARS_MAX]; 333 unsigned int n_assignments; 334 335 char *action_str[HIST_ACTIONS_MAX]; 336 unsigned int n_actions; 337 338 struct var_defs var_defs; 339 }; 340 341 struct field_var { 342 struct hist_field *var; 343 struct hist_field *val; 344 }; 345 346 struct field_var_hist { 347 struct hist_trigger_data *hist_data; 348 char *cmd; 349 }; 350 351 struct hist_trigger_data { 352 struct hist_field *fields[HIST_FIELDS_MAX]; 353 unsigned int n_vals; 354 unsigned int n_keys; 355 unsigned int n_fields; 356 unsigned int n_vars; 357 unsigned int key_size; 358 struct tracing_map_sort_key sort_keys[TRACING_MAP_SORT_KEYS_MAX]; 359 unsigned int n_sort_keys; 360 struct trace_event_file *event_file; 361 struct hist_trigger_attrs *attrs; 362 struct tracing_map *map; 363 bool enable_timestamps; 364 bool remove; 365 struct hist_field *var_refs[TRACING_MAP_VARS_MAX]; 366 unsigned int n_var_refs; 367 368 struct action_data *actions[HIST_ACTIONS_MAX]; 369 unsigned int n_actions; 370 371 struct field_var *field_vars[SYNTH_FIELDS_MAX]; 372 unsigned int n_field_vars; 373 unsigned int n_field_var_str; 374 struct field_var_hist *field_var_hists[SYNTH_FIELDS_MAX]; 375 unsigned int n_field_var_hists; 376 377 struct field_var *save_vars[SYNTH_FIELDS_MAX]; 378 unsigned int n_save_vars; 379 unsigned int n_save_var_str; 380 }; 381 382 static int synth_event_create(int argc, const char **argv); 383 static int synth_event_show(struct seq_file *m, struct dyn_event *ev); 384 static int synth_event_release(struct dyn_event *ev); 385 static bool synth_event_is_busy(struct dyn_event *ev); 386 static bool synth_event_match(const char *system, const char *event, 387 int argc, const char **argv, struct dyn_event *ev); 388 389 static struct dyn_event_operations synth_event_ops = { 390 .create = synth_event_create, 391 .show = synth_event_show, 392 .is_busy = synth_event_is_busy, 393 .free = synth_event_release, 394 .match = synth_event_match, 395 }; 396 397 struct synth_field { 398 char *type; 399 char *name; 400 size_t size; 401 bool is_signed; 402 bool is_string; 403 }; 404 405 struct synth_event { 406 struct dyn_event devent; 407 int ref; 408 char *name; 409 struct synth_field **fields; 410 unsigned int n_fields; 411 unsigned int n_u64; 412 struct trace_event_class class; 413 struct trace_event_call call; 414 struct tracepoint *tp; 415 }; 416 417 static bool is_synth_event(struct dyn_event *ev) 418 { 419 return ev->ops == &synth_event_ops; 420 } 421 422 static struct synth_event *to_synth_event(struct dyn_event *ev) 423 { 424 return container_of(ev, struct synth_event, devent); 425 } 426 427 static bool synth_event_is_busy(struct dyn_event *ev) 428 { 429 struct synth_event *event = to_synth_event(ev); 430 431 return event->ref != 0; 432 } 433 434 static bool synth_event_match(const char *system, const char *event, 435 int argc, const char **argv, struct dyn_event *ev) 436 { 437 struct synth_event *sev = to_synth_event(ev); 438 439 return strcmp(sev->name, event) == 0 && 440 (!system || strcmp(system, SYNTH_SYSTEM) == 0); 441 } 442 443 struct action_data; 444 445 typedef void (*action_fn_t) (struct hist_trigger_data *hist_data, 446 struct tracing_map_elt *elt, void *rec, 447 struct ring_buffer_event *rbe, void *key, 448 struct action_data *data, u64 *var_ref_vals); 449 450 typedef bool (*check_track_val_fn_t) (u64 track_val, u64 var_val); 451 452 enum handler_id { 453 HANDLER_ONMATCH = 1, 454 HANDLER_ONMAX, 455 HANDLER_ONCHANGE, 456 }; 457 458 enum action_id { 459 ACTION_SAVE = 1, 460 ACTION_TRACE, 461 ACTION_SNAPSHOT, 462 }; 463 464 struct action_data { 465 enum handler_id handler; 466 enum action_id action; 467 char *action_name; 468 action_fn_t fn; 469 470 unsigned int n_params; 471 char *params[SYNTH_FIELDS_MAX]; 472 473 /* 474 * When a histogram trigger is hit, the values of any 475 * references to variables, including variables being passed 476 * as parameters to synthetic events, are collected into a 477 * var_ref_vals array. This var_ref_idx is the index of the 478 * first param in the array to be passed to the synthetic 479 * event invocation. 480 */ 481 unsigned int var_ref_idx; 482 struct synth_event *synth_event; 483 bool use_trace_keyword; 484 char *synth_event_name; 485 486 union { 487 struct { 488 char *event; 489 char *event_system; 490 } match_data; 491 492 struct { 493 /* 494 * var_str contains the $-unstripped variable 495 * name referenced by var_ref, and used when 496 * printing the action. Because var_ref 497 * creation is deferred to create_actions(), 498 * we need a per-action way to save it until 499 * then, thus var_str. 500 */ 501 char *var_str; 502 503 /* 504 * var_ref refers to the variable being 505 * tracked e.g onmax($var). 506 */ 507 struct hist_field *var_ref; 508 509 /* 510 * track_var contains the 'invisible' tracking 511 * variable created to keep the current 512 * e.g. max value. 513 */ 514 struct hist_field *track_var; 515 516 check_track_val_fn_t check_val; 517 action_fn_t save_data; 518 } track_data; 519 }; 520 }; 521 522 struct track_data { 523 u64 track_val; 524 bool updated; 525 526 unsigned int key_len; 527 void *key; 528 struct tracing_map_elt elt; 529 530 struct action_data *action_data; 531 struct hist_trigger_data *hist_data; 532 }; 533 534 struct hist_elt_data { 535 char *comm; 536 u64 *var_ref_vals; 537 char *field_var_str[SYNTH_FIELDS_MAX]; 538 }; 539 540 struct snapshot_context { 541 struct tracing_map_elt *elt; 542 void *key; 543 }; 544 545 static void track_data_free(struct track_data *track_data) 546 { 547 struct hist_elt_data *elt_data; 548 549 if (!track_data) 550 return; 551 552 kfree(track_data->key); 553 554 elt_data = track_data->elt.private_data; 555 if (elt_data) { 556 kfree(elt_data->comm); 557 kfree(elt_data); 558 } 559 560 kfree(track_data); 561 } 562 563 static struct track_data *track_data_alloc(unsigned int key_len, 564 struct action_data *action_data, 565 struct hist_trigger_data *hist_data) 566 { 567 struct track_data *data = kzalloc(sizeof(*data), GFP_KERNEL); 568 struct hist_elt_data *elt_data; 569 570 if (!data) 571 return ERR_PTR(-ENOMEM); 572 573 data->key = kzalloc(key_len, GFP_KERNEL); 574 if (!data->key) { 575 track_data_free(data); 576 return ERR_PTR(-ENOMEM); 577 } 578 579 data->key_len = key_len; 580 data->action_data = action_data; 581 data->hist_data = hist_data; 582 583 elt_data = kzalloc(sizeof(*elt_data), GFP_KERNEL); 584 if (!elt_data) { 585 track_data_free(data); 586 return ERR_PTR(-ENOMEM); 587 } 588 data->elt.private_data = elt_data; 589 590 elt_data->comm = kzalloc(TASK_COMM_LEN, GFP_KERNEL); 591 if (!elt_data->comm) { 592 track_data_free(data); 593 return ERR_PTR(-ENOMEM); 594 } 595 596 return data; 597 } 598 599 static char last_cmd[MAX_FILTER_STR_VAL]; 600 static char last_cmd_loc[MAX_FILTER_STR_VAL]; 601 602 static int errpos(char *str) 603 { 604 return err_pos(last_cmd, str); 605 } 606 607 static void last_cmd_set(struct trace_event_file *file, char *str) 608 { 609 const char *system = NULL, *name = NULL; 610 struct trace_event_call *call; 611 612 if (!str) 613 return; 614 615 strcpy(last_cmd, "hist:"); 616 strncat(last_cmd, str, MAX_FILTER_STR_VAL - 1 - sizeof("hist:")); 617 618 if (file) { 619 call = file->event_call; 620 621 system = call->class->system; 622 if (system) { 623 name = trace_event_name(call); 624 if (!name) 625 system = NULL; 626 } 627 } 628 629 if (system) 630 snprintf(last_cmd_loc, MAX_FILTER_STR_VAL, "hist:%s:%s", system, name); 631 } 632 633 static void hist_err(struct trace_array *tr, u8 err_type, u8 err_pos) 634 { 635 tracing_log_err(tr, last_cmd_loc, last_cmd, err_text, 636 err_type, err_pos); 637 } 638 639 static void hist_err_clear(void) 640 { 641 last_cmd[0] = '\0'; 642 last_cmd_loc[0] = '\0'; 643 } 644 645 struct synth_trace_event { 646 struct trace_entry ent; 647 u64 fields[]; 648 }; 649 650 static int synth_event_define_fields(struct trace_event_call *call) 651 { 652 struct synth_trace_event trace; 653 int offset = offsetof(typeof(trace), fields); 654 struct synth_event *event = call->data; 655 unsigned int i, size, n_u64; 656 char *name, *type; 657 bool is_signed; 658 int ret = 0; 659 660 for (i = 0, n_u64 = 0; i < event->n_fields; i++) { 661 size = event->fields[i]->size; 662 is_signed = event->fields[i]->is_signed; 663 type = event->fields[i]->type; 664 name = event->fields[i]->name; 665 ret = trace_define_field(call, type, name, offset, size, 666 is_signed, FILTER_OTHER); 667 if (ret) 668 break; 669 670 if (event->fields[i]->is_string) { 671 offset += STR_VAR_LEN_MAX; 672 n_u64 += STR_VAR_LEN_MAX / sizeof(u64); 673 } else { 674 offset += sizeof(u64); 675 n_u64++; 676 } 677 } 678 679 event->n_u64 = n_u64; 680 681 return ret; 682 } 683 684 static bool synth_field_signed(char *type) 685 { 686 if (str_has_prefix(type, "u")) 687 return false; 688 if (strcmp(type, "gfp_t") == 0) 689 return false; 690 691 return true; 692 } 693 694 static int synth_field_is_string(char *type) 695 { 696 if (strstr(type, "char[") != NULL) 697 return true; 698 699 return false; 700 } 701 702 static int synth_field_string_size(char *type) 703 { 704 char buf[4], *end, *start; 705 unsigned int len; 706 int size, err; 707 708 start = strstr(type, "char["); 709 if (start == NULL) 710 return -EINVAL; 711 start += sizeof("char[") - 1; 712 713 end = strchr(type, ']'); 714 if (!end || end < start) 715 return -EINVAL; 716 717 len = end - start; 718 if (len > 3) 719 return -EINVAL; 720 721 strncpy(buf, start, len); 722 buf[len] = '\0'; 723 724 err = kstrtouint(buf, 0, &size); 725 if (err) 726 return err; 727 728 if (size > STR_VAR_LEN_MAX) 729 return -EINVAL; 730 731 return size; 732 } 733 734 static int synth_field_size(char *type) 735 { 736 int size = 0; 737 738 if (strcmp(type, "s64") == 0) 739 size = sizeof(s64); 740 else if (strcmp(type, "u64") == 0) 741 size = sizeof(u64); 742 else if (strcmp(type, "s32") == 0) 743 size = sizeof(s32); 744 else if (strcmp(type, "u32") == 0) 745 size = sizeof(u32); 746 else if (strcmp(type, "s16") == 0) 747 size = sizeof(s16); 748 else if (strcmp(type, "u16") == 0) 749 size = sizeof(u16); 750 else if (strcmp(type, "s8") == 0) 751 size = sizeof(s8); 752 else if (strcmp(type, "u8") == 0) 753 size = sizeof(u8); 754 else if (strcmp(type, "char") == 0) 755 size = sizeof(char); 756 else if (strcmp(type, "unsigned char") == 0) 757 size = sizeof(unsigned char); 758 else if (strcmp(type, "int") == 0) 759 size = sizeof(int); 760 else if (strcmp(type, "unsigned int") == 0) 761 size = sizeof(unsigned int); 762 else if (strcmp(type, "long") == 0) 763 size = sizeof(long); 764 else if (strcmp(type, "unsigned long") == 0) 765 size = sizeof(unsigned long); 766 else if (strcmp(type, "pid_t") == 0) 767 size = sizeof(pid_t); 768 else if (strcmp(type, "gfp_t") == 0) 769 size = sizeof(gfp_t); 770 else if (synth_field_is_string(type)) 771 size = synth_field_string_size(type); 772 773 return size; 774 } 775 776 static const char *synth_field_fmt(char *type) 777 { 778 const char *fmt = "%llu"; 779 780 if (strcmp(type, "s64") == 0) 781 fmt = "%lld"; 782 else if (strcmp(type, "u64") == 0) 783 fmt = "%llu"; 784 else if (strcmp(type, "s32") == 0) 785 fmt = "%d"; 786 else if (strcmp(type, "u32") == 0) 787 fmt = "%u"; 788 else if (strcmp(type, "s16") == 0) 789 fmt = "%d"; 790 else if (strcmp(type, "u16") == 0) 791 fmt = "%u"; 792 else if (strcmp(type, "s8") == 0) 793 fmt = "%d"; 794 else if (strcmp(type, "u8") == 0) 795 fmt = "%u"; 796 else if (strcmp(type, "char") == 0) 797 fmt = "%d"; 798 else if (strcmp(type, "unsigned char") == 0) 799 fmt = "%u"; 800 else if (strcmp(type, "int") == 0) 801 fmt = "%d"; 802 else if (strcmp(type, "unsigned int") == 0) 803 fmt = "%u"; 804 else if (strcmp(type, "long") == 0) 805 fmt = "%ld"; 806 else if (strcmp(type, "unsigned long") == 0) 807 fmt = "%lu"; 808 else if (strcmp(type, "pid_t") == 0) 809 fmt = "%d"; 810 else if (strcmp(type, "gfp_t") == 0) 811 fmt = "%x"; 812 else if (synth_field_is_string(type)) 813 fmt = "%s"; 814 815 return fmt; 816 } 817 818 static enum print_line_t print_synth_event(struct trace_iterator *iter, 819 int flags, 820 struct trace_event *event) 821 { 822 struct trace_array *tr = iter->tr; 823 struct trace_seq *s = &iter->seq; 824 struct synth_trace_event *entry; 825 struct synth_event *se; 826 unsigned int i, n_u64; 827 char print_fmt[32]; 828 const char *fmt; 829 830 entry = (struct synth_trace_event *)iter->ent; 831 se = container_of(event, struct synth_event, call.event); 832 833 trace_seq_printf(s, "%s: ", se->name); 834 835 for (i = 0, n_u64 = 0; i < se->n_fields; i++) { 836 if (trace_seq_has_overflowed(s)) 837 goto end; 838 839 fmt = synth_field_fmt(se->fields[i]->type); 840 841 /* parameter types */ 842 if (tr && tr->trace_flags & TRACE_ITER_VERBOSE) 843 trace_seq_printf(s, "%s ", fmt); 844 845 snprintf(print_fmt, sizeof(print_fmt), "%%s=%s%%s", fmt); 846 847 /* parameter values */ 848 if (se->fields[i]->is_string) { 849 trace_seq_printf(s, print_fmt, se->fields[i]->name, 850 (char *)&entry->fields[n_u64], 851 i == se->n_fields - 1 ? "" : " "); 852 n_u64 += STR_VAR_LEN_MAX / sizeof(u64); 853 } else { 854 struct trace_print_flags __flags[] = { 855 __def_gfpflag_names, {-1, NULL} }; 856 857 trace_seq_printf(s, print_fmt, se->fields[i]->name, 858 entry->fields[n_u64], 859 i == se->n_fields - 1 ? "" : " "); 860 861 if (strcmp(se->fields[i]->type, "gfp_t") == 0) { 862 trace_seq_puts(s, " ("); 863 trace_print_flags_seq(s, "|", 864 entry->fields[n_u64], 865 __flags); 866 trace_seq_putc(s, ')'); 867 } 868 n_u64++; 869 } 870 } 871 end: 872 trace_seq_putc(s, '\n'); 873 874 return trace_handle_return(s); 875 } 876 877 static struct trace_event_functions synth_event_funcs = { 878 .trace = print_synth_event 879 }; 880 881 static notrace void trace_event_raw_event_synth(void *__data, 882 u64 *var_ref_vals, 883 unsigned int var_ref_idx) 884 { 885 struct trace_event_file *trace_file = __data; 886 struct synth_trace_event *entry; 887 struct trace_event_buffer fbuffer; 888 struct trace_buffer *buffer; 889 struct synth_event *event; 890 unsigned int i, n_u64; 891 int fields_size = 0; 892 893 event = trace_file->event_call->data; 894 895 if (trace_trigger_soft_disabled(trace_file)) 896 return; 897 898 fields_size = event->n_u64 * sizeof(u64); 899 900 /* 901 * Avoid ring buffer recursion detection, as this event 902 * is being performed within another event. 903 */ 904 buffer = trace_file->tr->array_buffer.buffer; 905 ring_buffer_nest_start(buffer); 906 907 entry = trace_event_buffer_reserve(&fbuffer, trace_file, 908 sizeof(*entry) + fields_size); 909 if (!entry) 910 goto out; 911 912 for (i = 0, n_u64 = 0; i < event->n_fields; i++) { 913 if (event->fields[i]->is_string) { 914 char *str_val = (char *)(long)var_ref_vals[var_ref_idx + i]; 915 char *str_field = (char *)&entry->fields[n_u64]; 916 917 strscpy(str_field, str_val, STR_VAR_LEN_MAX); 918 n_u64 += STR_VAR_LEN_MAX / sizeof(u64); 919 } else { 920 struct synth_field *field = event->fields[i]; 921 u64 val = var_ref_vals[var_ref_idx + i]; 922 923 switch (field->size) { 924 case 1: 925 *(u8 *)&entry->fields[n_u64] = (u8)val; 926 break; 927 928 case 2: 929 *(u16 *)&entry->fields[n_u64] = (u16)val; 930 break; 931 932 case 4: 933 *(u32 *)&entry->fields[n_u64] = (u32)val; 934 break; 935 936 default: 937 entry->fields[n_u64] = val; 938 break; 939 } 940 n_u64++; 941 } 942 } 943 944 trace_event_buffer_commit(&fbuffer); 945 out: 946 ring_buffer_nest_end(buffer); 947 } 948 949 static void free_synth_event_print_fmt(struct trace_event_call *call) 950 { 951 if (call) { 952 kfree(call->print_fmt); 953 call->print_fmt = NULL; 954 } 955 } 956 957 static int __set_synth_event_print_fmt(struct synth_event *event, 958 char *buf, int len) 959 { 960 const char *fmt; 961 int pos = 0; 962 int i; 963 964 /* When len=0, we just calculate the needed length */ 965 #define LEN_OR_ZERO (len ? len - pos : 0) 966 967 pos += snprintf(buf + pos, LEN_OR_ZERO, "\""); 968 for (i = 0; i < event->n_fields; i++) { 969 fmt = synth_field_fmt(event->fields[i]->type); 970 pos += snprintf(buf + pos, LEN_OR_ZERO, "%s=%s%s", 971 event->fields[i]->name, fmt, 972 i == event->n_fields - 1 ? "" : ", "); 973 } 974 pos += snprintf(buf + pos, LEN_OR_ZERO, "\""); 975 976 for (i = 0; i < event->n_fields; i++) { 977 pos += snprintf(buf + pos, LEN_OR_ZERO, 978 ", REC->%s", event->fields[i]->name); 979 } 980 981 #undef LEN_OR_ZERO 982 983 /* return the length of print_fmt */ 984 return pos; 985 } 986 987 static int set_synth_event_print_fmt(struct trace_event_call *call) 988 { 989 struct synth_event *event = call->data; 990 char *print_fmt; 991 int len; 992 993 /* First: called with 0 length to calculate the needed length */ 994 len = __set_synth_event_print_fmt(event, NULL, 0); 995 996 print_fmt = kmalloc(len + 1, GFP_KERNEL); 997 if (!print_fmt) 998 return -ENOMEM; 999 1000 /* Second: actually write the @print_fmt */ 1001 __set_synth_event_print_fmt(event, print_fmt, len + 1); 1002 call->print_fmt = print_fmt; 1003 1004 return 0; 1005 } 1006 1007 static void free_synth_field(struct synth_field *field) 1008 { 1009 kfree(field->type); 1010 kfree(field->name); 1011 kfree(field); 1012 } 1013 1014 static struct synth_field *parse_synth_field(int argc, const char **argv, 1015 int *consumed) 1016 { 1017 struct synth_field *field; 1018 const char *prefix = NULL, *field_type = argv[0], *field_name, *array; 1019 int len, ret = 0; 1020 1021 if (field_type[0] == ';') 1022 field_type++; 1023 1024 if (!strcmp(field_type, "unsigned")) { 1025 if (argc < 3) 1026 return ERR_PTR(-EINVAL); 1027 prefix = "unsigned "; 1028 field_type = argv[1]; 1029 field_name = argv[2]; 1030 *consumed = 3; 1031 } else { 1032 field_name = argv[1]; 1033 *consumed = 2; 1034 } 1035 1036 field = kzalloc(sizeof(*field), GFP_KERNEL); 1037 if (!field) 1038 return ERR_PTR(-ENOMEM); 1039 1040 len = strlen(field_name); 1041 array = strchr(field_name, '['); 1042 if (array) 1043 len -= strlen(array); 1044 else if (field_name[len - 1] == ';') 1045 len--; 1046 1047 field->name = kmemdup_nul(field_name, len, GFP_KERNEL); 1048 if (!field->name) { 1049 ret = -ENOMEM; 1050 goto free; 1051 } 1052 1053 if (field_type[0] == ';') 1054 field_type++; 1055 len = strlen(field_type) + 1; 1056 if (array) 1057 len += strlen(array); 1058 if (prefix) 1059 len += strlen(prefix); 1060 1061 field->type = kzalloc(len, GFP_KERNEL); 1062 if (!field->type) { 1063 ret = -ENOMEM; 1064 goto free; 1065 } 1066 if (prefix) 1067 strcat(field->type, prefix); 1068 strcat(field->type, field_type); 1069 if (array) { 1070 strcat(field->type, array); 1071 if (field->type[len - 1] == ';') 1072 field->type[len - 1] = '\0'; 1073 } 1074 1075 field->size = synth_field_size(field->type); 1076 if (!field->size) { 1077 ret = -EINVAL; 1078 goto free; 1079 } 1080 1081 if (synth_field_is_string(field->type)) 1082 field->is_string = true; 1083 1084 field->is_signed = synth_field_signed(field->type); 1085 1086 out: 1087 return field; 1088 free: 1089 free_synth_field(field); 1090 field = ERR_PTR(ret); 1091 goto out; 1092 } 1093 1094 static void free_synth_tracepoint(struct tracepoint *tp) 1095 { 1096 if (!tp) 1097 return; 1098 1099 kfree(tp->name); 1100 kfree(tp); 1101 } 1102 1103 static struct tracepoint *alloc_synth_tracepoint(char *name) 1104 { 1105 struct tracepoint *tp; 1106 1107 tp = kzalloc(sizeof(*tp), GFP_KERNEL); 1108 if (!tp) 1109 return ERR_PTR(-ENOMEM); 1110 1111 tp->name = kstrdup(name, GFP_KERNEL); 1112 if (!tp->name) { 1113 kfree(tp); 1114 return ERR_PTR(-ENOMEM); 1115 } 1116 1117 return tp; 1118 } 1119 1120 typedef void (*synth_probe_func_t) (void *__data, u64 *var_ref_vals, 1121 unsigned int var_ref_idx); 1122 1123 static inline void trace_synth(struct synth_event *event, u64 *var_ref_vals, 1124 unsigned int var_ref_idx) 1125 { 1126 struct tracepoint *tp = event->tp; 1127 1128 if (unlikely(atomic_read(&tp->key.enabled) > 0)) { 1129 struct tracepoint_func *probe_func_ptr; 1130 synth_probe_func_t probe_func; 1131 void *__data; 1132 1133 if (!(cpu_online(raw_smp_processor_id()))) 1134 return; 1135 1136 probe_func_ptr = rcu_dereference_sched((tp)->funcs); 1137 if (probe_func_ptr) { 1138 do { 1139 probe_func = probe_func_ptr->func; 1140 __data = probe_func_ptr->data; 1141 probe_func(__data, var_ref_vals, var_ref_idx); 1142 } while ((++probe_func_ptr)->func); 1143 } 1144 } 1145 } 1146 1147 static struct synth_event *find_synth_event(const char *name) 1148 { 1149 struct dyn_event *pos; 1150 struct synth_event *event; 1151 1152 for_each_dyn_event(pos) { 1153 if (!is_synth_event(pos)) 1154 continue; 1155 event = to_synth_event(pos); 1156 if (strcmp(event->name, name) == 0) 1157 return event; 1158 } 1159 1160 return NULL; 1161 } 1162 1163 static int register_synth_event(struct synth_event *event) 1164 { 1165 struct trace_event_call *call = &event->call; 1166 int ret = 0; 1167 1168 event->call.class = &event->class; 1169 event->class.system = kstrdup(SYNTH_SYSTEM, GFP_KERNEL); 1170 if (!event->class.system) { 1171 ret = -ENOMEM; 1172 goto out; 1173 } 1174 1175 event->tp = alloc_synth_tracepoint(event->name); 1176 if (IS_ERR(event->tp)) { 1177 ret = PTR_ERR(event->tp); 1178 event->tp = NULL; 1179 goto out; 1180 } 1181 1182 INIT_LIST_HEAD(&call->class->fields); 1183 call->event.funcs = &synth_event_funcs; 1184 call->class->define_fields = synth_event_define_fields; 1185 1186 ret = register_trace_event(&call->event); 1187 if (!ret) { 1188 ret = -ENODEV; 1189 goto out; 1190 } 1191 call->flags = TRACE_EVENT_FL_TRACEPOINT; 1192 call->class->reg = trace_event_reg; 1193 call->class->probe = trace_event_raw_event_synth; 1194 call->data = event; 1195 call->tp = event->tp; 1196 1197 ret = trace_add_event_call(call); 1198 if (ret) { 1199 pr_warn("Failed to register synthetic event: %s\n", 1200 trace_event_name(call)); 1201 goto err; 1202 } 1203 1204 ret = set_synth_event_print_fmt(call); 1205 if (ret < 0) { 1206 trace_remove_event_call(call); 1207 goto err; 1208 } 1209 out: 1210 return ret; 1211 err: 1212 unregister_trace_event(&call->event); 1213 goto out; 1214 } 1215 1216 static int unregister_synth_event(struct synth_event *event) 1217 { 1218 struct trace_event_call *call = &event->call; 1219 int ret; 1220 1221 ret = trace_remove_event_call(call); 1222 1223 return ret; 1224 } 1225 1226 static void free_synth_event(struct synth_event *event) 1227 { 1228 unsigned int i; 1229 1230 if (!event) 1231 return; 1232 1233 for (i = 0; i < event->n_fields; i++) 1234 free_synth_field(event->fields[i]); 1235 1236 kfree(event->fields); 1237 kfree(event->name); 1238 kfree(event->class.system); 1239 free_synth_tracepoint(event->tp); 1240 free_synth_event_print_fmt(&event->call); 1241 kfree(event); 1242 } 1243 1244 static struct synth_event *alloc_synth_event(const char *name, int n_fields, 1245 struct synth_field **fields) 1246 { 1247 struct synth_event *event; 1248 unsigned int i; 1249 1250 event = kzalloc(sizeof(*event), GFP_KERNEL); 1251 if (!event) { 1252 event = ERR_PTR(-ENOMEM); 1253 goto out; 1254 } 1255 1256 event->name = kstrdup(name, GFP_KERNEL); 1257 if (!event->name) { 1258 kfree(event); 1259 event = ERR_PTR(-ENOMEM); 1260 goto out; 1261 } 1262 1263 event->fields = kcalloc(n_fields, sizeof(*event->fields), GFP_KERNEL); 1264 if (!event->fields) { 1265 free_synth_event(event); 1266 event = ERR_PTR(-ENOMEM); 1267 goto out; 1268 } 1269 1270 dyn_event_init(&event->devent, &synth_event_ops); 1271 1272 for (i = 0; i < n_fields; i++) 1273 event->fields[i] = fields[i]; 1274 1275 event->n_fields = n_fields; 1276 out: 1277 return event; 1278 } 1279 1280 static void action_trace(struct hist_trigger_data *hist_data, 1281 struct tracing_map_elt *elt, void *rec, 1282 struct ring_buffer_event *rbe, void *key, 1283 struct action_data *data, u64 *var_ref_vals) 1284 { 1285 struct synth_event *event = data->synth_event; 1286 1287 trace_synth(event, var_ref_vals, data->var_ref_idx); 1288 } 1289 1290 struct hist_var_data { 1291 struct list_head list; 1292 struct hist_trigger_data *hist_data; 1293 }; 1294 1295 static int __create_synth_event(int argc, const char *name, const char **argv) 1296 { 1297 struct synth_field *field, *fields[SYNTH_FIELDS_MAX]; 1298 struct synth_event *event = NULL; 1299 int i, consumed = 0, n_fields = 0, ret = 0; 1300 1301 /* 1302 * Argument syntax: 1303 * - Add synthetic event: <event_name> field[;field] ... 1304 * - Remove synthetic event: !<event_name> field[;field] ... 1305 * where 'field' = type field_name 1306 */ 1307 1308 if (name[0] == '\0' || argc < 1) 1309 return -EINVAL; 1310 1311 mutex_lock(&event_mutex); 1312 1313 event = find_synth_event(name); 1314 if (event) { 1315 ret = -EEXIST; 1316 goto out; 1317 } 1318 1319 for (i = 0; i < argc - 1; i++) { 1320 if (strcmp(argv[i], ";") == 0) 1321 continue; 1322 if (n_fields == SYNTH_FIELDS_MAX) { 1323 ret = -EINVAL; 1324 goto err; 1325 } 1326 1327 field = parse_synth_field(argc - i, &argv[i], &consumed); 1328 if (IS_ERR(field)) { 1329 ret = PTR_ERR(field); 1330 goto err; 1331 } 1332 fields[n_fields++] = field; 1333 i += consumed - 1; 1334 } 1335 1336 if (i < argc && strcmp(argv[i], ";") != 0) { 1337 ret = -EINVAL; 1338 goto err; 1339 } 1340 1341 event = alloc_synth_event(name, n_fields, fields); 1342 if (IS_ERR(event)) { 1343 ret = PTR_ERR(event); 1344 event = NULL; 1345 goto err; 1346 } 1347 ret = register_synth_event(event); 1348 if (!ret) 1349 dyn_event_add(&event->devent); 1350 else 1351 free_synth_event(event); 1352 out: 1353 mutex_unlock(&event_mutex); 1354 1355 return ret; 1356 err: 1357 for (i = 0; i < n_fields; i++) 1358 free_synth_field(fields[i]); 1359 1360 goto out; 1361 } 1362 1363 static int create_or_delete_synth_event(int argc, char **argv) 1364 { 1365 const char *name = argv[0]; 1366 struct synth_event *event = NULL; 1367 int ret; 1368 1369 /* trace_run_command() ensures argc != 0 */ 1370 if (name[0] == '!') { 1371 mutex_lock(&event_mutex); 1372 event = find_synth_event(name + 1); 1373 if (event) { 1374 if (event->ref) 1375 ret = -EBUSY; 1376 else { 1377 ret = unregister_synth_event(event); 1378 if (!ret) { 1379 dyn_event_remove(&event->devent); 1380 free_synth_event(event); 1381 } 1382 } 1383 } else 1384 ret = -ENOENT; 1385 mutex_unlock(&event_mutex); 1386 return ret; 1387 } 1388 1389 ret = __create_synth_event(argc - 1, name, (const char **)argv + 1); 1390 return ret == -ECANCELED ? -EINVAL : ret; 1391 } 1392 1393 int synth_event_run_command(const char *command) 1394 { 1395 return trace_run_command(command, create_or_delete_synth_event); 1396 } 1397 1398 static int synth_event_create(int argc, const char **argv) 1399 { 1400 const char *name = argv[0]; 1401 int len; 1402 1403 if (name[0] != 's' || name[1] != ':') 1404 return -ECANCELED; 1405 name += 2; 1406 1407 /* This interface accepts group name prefix */ 1408 if (strchr(name, '/')) { 1409 len = str_has_prefix(name, SYNTH_SYSTEM "/"); 1410 if (len == 0) 1411 return -EINVAL; 1412 name += len; 1413 } 1414 return __create_synth_event(argc - 1, name, argv + 1); 1415 } 1416 1417 static int synth_event_release(struct dyn_event *ev) 1418 { 1419 struct synth_event *event = to_synth_event(ev); 1420 int ret; 1421 1422 if (event->ref) 1423 return -EBUSY; 1424 1425 ret = unregister_synth_event(event); 1426 if (ret) 1427 return ret; 1428 1429 dyn_event_remove(ev); 1430 free_synth_event(event); 1431 return 0; 1432 } 1433 1434 static int __synth_event_show(struct seq_file *m, struct synth_event *event) 1435 { 1436 struct synth_field *field; 1437 unsigned int i; 1438 1439 seq_printf(m, "%s\t", event->name); 1440 1441 for (i = 0; i < event->n_fields; i++) { 1442 field = event->fields[i]; 1443 1444 /* parameter values */ 1445 seq_printf(m, "%s %s%s", field->type, field->name, 1446 i == event->n_fields - 1 ? "" : "; "); 1447 } 1448 1449 seq_putc(m, '\n'); 1450 1451 return 0; 1452 } 1453 1454 static int synth_event_show(struct seq_file *m, struct dyn_event *ev) 1455 { 1456 struct synth_event *event = to_synth_event(ev); 1457 1458 seq_printf(m, "s:%s/", event->class.system); 1459 1460 return __synth_event_show(m, event); 1461 } 1462 1463 static int synth_events_seq_show(struct seq_file *m, void *v) 1464 { 1465 struct dyn_event *ev = v; 1466 1467 if (!is_synth_event(ev)) 1468 return 0; 1469 1470 return __synth_event_show(m, to_synth_event(ev)); 1471 } 1472 1473 static const struct seq_operations synth_events_seq_op = { 1474 .start = dyn_event_seq_start, 1475 .next = dyn_event_seq_next, 1476 .stop = dyn_event_seq_stop, 1477 .show = synth_events_seq_show, 1478 }; 1479 1480 static int synth_events_open(struct inode *inode, struct file *file) 1481 { 1482 int ret; 1483 1484 ret = security_locked_down(LOCKDOWN_TRACEFS); 1485 if (ret) 1486 return ret; 1487 1488 if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) { 1489 ret = dyn_events_release_all(&synth_event_ops); 1490 if (ret < 0) 1491 return ret; 1492 } 1493 1494 return seq_open(file, &synth_events_seq_op); 1495 } 1496 1497 static ssize_t synth_events_write(struct file *file, 1498 const char __user *buffer, 1499 size_t count, loff_t *ppos) 1500 { 1501 return trace_parse_run_command(file, buffer, count, ppos, 1502 create_or_delete_synth_event); 1503 } 1504 1505 static const struct file_operations synth_events_fops = { 1506 .open = synth_events_open, 1507 .write = synth_events_write, 1508 .read = seq_read, 1509 .llseek = seq_lseek, 1510 .release = seq_release, 1511 }; 1512 1513 static u64 hist_field_timestamp(struct hist_field *hist_field, 1514 struct tracing_map_elt *elt, 1515 struct ring_buffer_event *rbe, 1516 void *event) 1517 { 1518 struct hist_trigger_data *hist_data = hist_field->hist_data; 1519 struct trace_array *tr = hist_data->event_file->tr; 1520 1521 u64 ts = ring_buffer_event_time_stamp(rbe); 1522 1523 if (hist_data->attrs->ts_in_usecs && trace_clock_in_ns(tr)) 1524 ts = ns2usecs(ts); 1525 1526 return ts; 1527 } 1528 1529 static u64 hist_field_cpu(struct hist_field *hist_field, 1530 struct tracing_map_elt *elt, 1531 struct ring_buffer_event *rbe, 1532 void *event) 1533 { 1534 int cpu = smp_processor_id(); 1535 1536 return cpu; 1537 } 1538 1539 /** 1540 * check_field_for_var_ref - Check if a VAR_REF field references a variable 1541 * @hist_field: The VAR_REF field to check 1542 * @var_data: The hist trigger that owns the variable 1543 * @var_idx: The trigger variable identifier 1544 * 1545 * Check the given VAR_REF field to see whether or not it references 1546 * the given variable associated with the given trigger. 1547 * 1548 * Return: The VAR_REF field if it does reference the variable, NULL if not 1549 */ 1550 static struct hist_field * 1551 check_field_for_var_ref(struct hist_field *hist_field, 1552 struct hist_trigger_data *var_data, 1553 unsigned int var_idx) 1554 { 1555 WARN_ON(!(hist_field && hist_field->flags & HIST_FIELD_FL_VAR_REF)); 1556 1557 if (hist_field && hist_field->var.idx == var_idx && 1558 hist_field->var.hist_data == var_data) 1559 return hist_field; 1560 1561 return NULL; 1562 } 1563 1564 /** 1565 * find_var_ref - Check if a trigger has a reference to a trigger variable 1566 * @hist_data: The hist trigger that might have a reference to the variable 1567 * @var_data: The hist trigger that owns the variable 1568 * @var_idx: The trigger variable identifier 1569 * 1570 * Check the list of var_refs[] on the first hist trigger to see 1571 * whether any of them are references to the variable on the second 1572 * trigger. 1573 * 1574 * Return: The VAR_REF field referencing the variable if so, NULL if not 1575 */ 1576 static struct hist_field *find_var_ref(struct hist_trigger_data *hist_data, 1577 struct hist_trigger_data *var_data, 1578 unsigned int var_idx) 1579 { 1580 struct hist_field *hist_field; 1581 unsigned int i; 1582 1583 for (i = 0; i < hist_data->n_var_refs; i++) { 1584 hist_field = hist_data->var_refs[i]; 1585 if (check_field_for_var_ref(hist_field, var_data, var_idx)) 1586 return hist_field; 1587 } 1588 1589 return NULL; 1590 } 1591 1592 /** 1593 * find_any_var_ref - Check if there is a reference to a given trigger variable 1594 * @hist_data: The hist trigger 1595 * @var_idx: The trigger variable identifier 1596 * 1597 * Check to see whether the given variable is currently referenced by 1598 * any other trigger. 1599 * 1600 * The trigger the variable is defined on is explicitly excluded - the 1601 * assumption being that a self-reference doesn't prevent a trigger 1602 * from being removed. 1603 * 1604 * Return: The VAR_REF field referencing the variable if so, NULL if not 1605 */ 1606 static struct hist_field *find_any_var_ref(struct hist_trigger_data *hist_data, 1607 unsigned int var_idx) 1608 { 1609 struct trace_array *tr = hist_data->event_file->tr; 1610 struct hist_field *found = NULL; 1611 struct hist_var_data *var_data; 1612 1613 list_for_each_entry(var_data, &tr->hist_vars, list) { 1614 if (var_data->hist_data == hist_data) 1615 continue; 1616 found = find_var_ref(var_data->hist_data, hist_data, var_idx); 1617 if (found) 1618 break; 1619 } 1620 1621 return found; 1622 } 1623 1624 /** 1625 * check_var_refs - Check if there is a reference to any of trigger's variables 1626 * @hist_data: The hist trigger 1627 * 1628 * A trigger can define one or more variables. If any one of them is 1629 * currently referenced by any other trigger, this function will 1630 * determine that. 1631 1632 * Typically used to determine whether or not a trigger can be removed 1633 * - if there are any references to a trigger's variables, it cannot. 1634 * 1635 * Return: True if there is a reference to any of trigger's variables 1636 */ 1637 static bool check_var_refs(struct hist_trigger_data *hist_data) 1638 { 1639 struct hist_field *field; 1640 bool found = false; 1641 int i; 1642 1643 for_each_hist_field(i, hist_data) { 1644 field = hist_data->fields[i]; 1645 if (field && field->flags & HIST_FIELD_FL_VAR) { 1646 if (find_any_var_ref(hist_data, field->var.idx)) { 1647 found = true; 1648 break; 1649 } 1650 } 1651 } 1652 1653 return found; 1654 } 1655 1656 static struct hist_var_data *find_hist_vars(struct hist_trigger_data *hist_data) 1657 { 1658 struct trace_array *tr = hist_data->event_file->tr; 1659 struct hist_var_data *var_data, *found = NULL; 1660 1661 list_for_each_entry(var_data, &tr->hist_vars, list) { 1662 if (var_data->hist_data == hist_data) { 1663 found = var_data; 1664 break; 1665 } 1666 } 1667 1668 return found; 1669 } 1670 1671 static bool field_has_hist_vars(struct hist_field *hist_field, 1672 unsigned int level) 1673 { 1674 int i; 1675 1676 if (level > 3) 1677 return false; 1678 1679 if (!hist_field) 1680 return false; 1681 1682 if (hist_field->flags & HIST_FIELD_FL_VAR || 1683 hist_field->flags & HIST_FIELD_FL_VAR_REF) 1684 return true; 1685 1686 for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++) { 1687 struct hist_field *operand; 1688 1689 operand = hist_field->operands[i]; 1690 if (field_has_hist_vars(operand, level + 1)) 1691 return true; 1692 } 1693 1694 return false; 1695 } 1696 1697 static bool has_hist_vars(struct hist_trigger_data *hist_data) 1698 { 1699 struct hist_field *hist_field; 1700 int i; 1701 1702 for_each_hist_field(i, hist_data) { 1703 hist_field = hist_data->fields[i]; 1704 if (field_has_hist_vars(hist_field, 0)) 1705 return true; 1706 } 1707 1708 return false; 1709 } 1710 1711 static int save_hist_vars(struct hist_trigger_data *hist_data) 1712 { 1713 struct trace_array *tr = hist_data->event_file->tr; 1714 struct hist_var_data *var_data; 1715 1716 var_data = find_hist_vars(hist_data); 1717 if (var_data) 1718 return 0; 1719 1720 if (tracing_check_open_get_tr(tr)) 1721 return -ENODEV; 1722 1723 var_data = kzalloc(sizeof(*var_data), GFP_KERNEL); 1724 if (!var_data) { 1725 trace_array_put(tr); 1726 return -ENOMEM; 1727 } 1728 1729 var_data->hist_data = hist_data; 1730 list_add(&var_data->list, &tr->hist_vars); 1731 1732 return 0; 1733 } 1734 1735 static void remove_hist_vars(struct hist_trigger_data *hist_data) 1736 { 1737 struct trace_array *tr = hist_data->event_file->tr; 1738 struct hist_var_data *var_data; 1739 1740 var_data = find_hist_vars(hist_data); 1741 if (!var_data) 1742 return; 1743 1744 if (WARN_ON(check_var_refs(hist_data))) 1745 return; 1746 1747 list_del(&var_data->list); 1748 1749 kfree(var_data); 1750 1751 trace_array_put(tr); 1752 } 1753 1754 static struct hist_field *find_var_field(struct hist_trigger_data *hist_data, 1755 const char *var_name) 1756 { 1757 struct hist_field *hist_field, *found = NULL; 1758 int i; 1759 1760 for_each_hist_field(i, hist_data) { 1761 hist_field = hist_data->fields[i]; 1762 if (hist_field && hist_field->flags & HIST_FIELD_FL_VAR && 1763 strcmp(hist_field->var.name, var_name) == 0) { 1764 found = hist_field; 1765 break; 1766 } 1767 } 1768 1769 return found; 1770 } 1771 1772 static struct hist_field *find_var(struct hist_trigger_data *hist_data, 1773 struct trace_event_file *file, 1774 const char *var_name) 1775 { 1776 struct hist_trigger_data *test_data; 1777 struct event_trigger_data *test; 1778 struct hist_field *hist_field; 1779 1780 lockdep_assert_held(&event_mutex); 1781 1782 hist_field = find_var_field(hist_data, var_name); 1783 if (hist_field) 1784 return hist_field; 1785 1786 list_for_each_entry(test, &file->triggers, list) { 1787 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 1788 test_data = test->private_data; 1789 hist_field = find_var_field(test_data, var_name); 1790 if (hist_field) 1791 return hist_field; 1792 } 1793 } 1794 1795 return NULL; 1796 } 1797 1798 static struct trace_event_file *find_var_file(struct trace_array *tr, 1799 char *system, 1800 char *event_name, 1801 char *var_name) 1802 { 1803 struct hist_trigger_data *var_hist_data; 1804 struct hist_var_data *var_data; 1805 struct trace_event_file *file, *found = NULL; 1806 1807 if (system) 1808 return find_event_file(tr, system, event_name); 1809 1810 list_for_each_entry(var_data, &tr->hist_vars, list) { 1811 var_hist_data = var_data->hist_data; 1812 file = var_hist_data->event_file; 1813 if (file == found) 1814 continue; 1815 1816 if (find_var_field(var_hist_data, var_name)) { 1817 if (found) { 1818 hist_err(tr, HIST_ERR_VAR_NOT_UNIQUE, errpos(var_name)); 1819 return NULL; 1820 } 1821 1822 found = file; 1823 } 1824 } 1825 1826 return found; 1827 } 1828 1829 static struct hist_field *find_file_var(struct trace_event_file *file, 1830 const char *var_name) 1831 { 1832 struct hist_trigger_data *test_data; 1833 struct event_trigger_data *test; 1834 struct hist_field *hist_field; 1835 1836 lockdep_assert_held(&event_mutex); 1837 1838 list_for_each_entry(test, &file->triggers, list) { 1839 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 1840 test_data = test->private_data; 1841 hist_field = find_var_field(test_data, var_name); 1842 if (hist_field) 1843 return hist_field; 1844 } 1845 } 1846 1847 return NULL; 1848 } 1849 1850 static struct hist_field * 1851 find_match_var(struct hist_trigger_data *hist_data, char *var_name) 1852 { 1853 struct trace_array *tr = hist_data->event_file->tr; 1854 struct hist_field *hist_field, *found = NULL; 1855 struct trace_event_file *file; 1856 unsigned int i; 1857 1858 for (i = 0; i < hist_data->n_actions; i++) { 1859 struct action_data *data = hist_data->actions[i]; 1860 1861 if (data->handler == HANDLER_ONMATCH) { 1862 char *system = data->match_data.event_system; 1863 char *event_name = data->match_data.event; 1864 1865 file = find_var_file(tr, system, event_name, var_name); 1866 if (!file) 1867 continue; 1868 hist_field = find_file_var(file, var_name); 1869 if (hist_field) { 1870 if (found) { 1871 hist_err(tr, HIST_ERR_VAR_NOT_UNIQUE, 1872 errpos(var_name)); 1873 return ERR_PTR(-EINVAL); 1874 } 1875 1876 found = hist_field; 1877 } 1878 } 1879 } 1880 return found; 1881 } 1882 1883 static struct hist_field *find_event_var(struct hist_trigger_data *hist_data, 1884 char *system, 1885 char *event_name, 1886 char *var_name) 1887 { 1888 struct trace_array *tr = hist_data->event_file->tr; 1889 struct hist_field *hist_field = NULL; 1890 struct trace_event_file *file; 1891 1892 if (!system || !event_name) { 1893 hist_field = find_match_var(hist_data, var_name); 1894 if (IS_ERR(hist_field)) 1895 return NULL; 1896 if (hist_field) 1897 return hist_field; 1898 } 1899 1900 file = find_var_file(tr, system, event_name, var_name); 1901 if (!file) 1902 return NULL; 1903 1904 hist_field = find_file_var(file, var_name); 1905 1906 return hist_field; 1907 } 1908 1909 static u64 hist_field_var_ref(struct hist_field *hist_field, 1910 struct tracing_map_elt *elt, 1911 struct ring_buffer_event *rbe, 1912 void *event) 1913 { 1914 struct hist_elt_data *elt_data; 1915 u64 var_val = 0; 1916 1917 if (WARN_ON_ONCE(!elt)) 1918 return var_val; 1919 1920 elt_data = elt->private_data; 1921 var_val = elt_data->var_ref_vals[hist_field->var_ref_idx]; 1922 1923 return var_val; 1924 } 1925 1926 static bool resolve_var_refs(struct hist_trigger_data *hist_data, void *key, 1927 u64 *var_ref_vals, bool self) 1928 { 1929 struct hist_trigger_data *var_data; 1930 struct tracing_map_elt *var_elt; 1931 struct hist_field *hist_field; 1932 unsigned int i, var_idx; 1933 bool resolved = true; 1934 u64 var_val = 0; 1935 1936 for (i = 0; i < hist_data->n_var_refs; i++) { 1937 hist_field = hist_data->var_refs[i]; 1938 var_idx = hist_field->var.idx; 1939 var_data = hist_field->var.hist_data; 1940 1941 if (var_data == NULL) { 1942 resolved = false; 1943 break; 1944 } 1945 1946 if ((self && var_data != hist_data) || 1947 (!self && var_data == hist_data)) 1948 continue; 1949 1950 var_elt = tracing_map_lookup(var_data->map, key); 1951 if (!var_elt) { 1952 resolved = false; 1953 break; 1954 } 1955 1956 if (!tracing_map_var_set(var_elt, var_idx)) { 1957 resolved = false; 1958 break; 1959 } 1960 1961 if (self || !hist_field->read_once) 1962 var_val = tracing_map_read_var(var_elt, var_idx); 1963 else 1964 var_val = tracing_map_read_var_once(var_elt, var_idx); 1965 1966 var_ref_vals[i] = var_val; 1967 } 1968 1969 return resolved; 1970 } 1971 1972 static const char *hist_field_name(struct hist_field *field, 1973 unsigned int level) 1974 { 1975 const char *field_name = ""; 1976 1977 if (level > 1) 1978 return field_name; 1979 1980 if (field->field) 1981 field_name = field->field->name; 1982 else if (field->flags & HIST_FIELD_FL_LOG2 || 1983 field->flags & HIST_FIELD_FL_ALIAS) 1984 field_name = hist_field_name(field->operands[0], ++level); 1985 else if (field->flags & HIST_FIELD_FL_CPU) 1986 field_name = "cpu"; 1987 else if (field->flags & HIST_FIELD_FL_EXPR || 1988 field->flags & HIST_FIELD_FL_VAR_REF) { 1989 if (field->system) { 1990 static char full_name[MAX_FILTER_STR_VAL]; 1991 1992 strcat(full_name, field->system); 1993 strcat(full_name, "."); 1994 strcat(full_name, field->event_name); 1995 strcat(full_name, "."); 1996 strcat(full_name, field->name); 1997 field_name = full_name; 1998 } else 1999 field_name = field->name; 2000 } else if (field->flags & HIST_FIELD_FL_TIMESTAMP) 2001 field_name = "common_timestamp"; 2002 2003 if (field_name == NULL) 2004 field_name = ""; 2005 2006 return field_name; 2007 } 2008 2009 static hist_field_fn_t select_value_fn(int field_size, int field_is_signed) 2010 { 2011 hist_field_fn_t fn = NULL; 2012 2013 switch (field_size) { 2014 case 8: 2015 if (field_is_signed) 2016 fn = hist_field_s64; 2017 else 2018 fn = hist_field_u64; 2019 break; 2020 case 4: 2021 if (field_is_signed) 2022 fn = hist_field_s32; 2023 else 2024 fn = hist_field_u32; 2025 break; 2026 case 2: 2027 if (field_is_signed) 2028 fn = hist_field_s16; 2029 else 2030 fn = hist_field_u16; 2031 break; 2032 case 1: 2033 if (field_is_signed) 2034 fn = hist_field_s8; 2035 else 2036 fn = hist_field_u8; 2037 break; 2038 } 2039 2040 return fn; 2041 } 2042 2043 static int parse_map_size(char *str) 2044 { 2045 unsigned long size, map_bits; 2046 int ret; 2047 2048 ret = kstrtoul(str, 0, &size); 2049 if (ret) 2050 goto out; 2051 2052 map_bits = ilog2(roundup_pow_of_two(size)); 2053 if (map_bits < TRACING_MAP_BITS_MIN || 2054 map_bits > TRACING_MAP_BITS_MAX) 2055 ret = -EINVAL; 2056 else 2057 ret = map_bits; 2058 out: 2059 return ret; 2060 } 2061 2062 static void destroy_hist_trigger_attrs(struct hist_trigger_attrs *attrs) 2063 { 2064 unsigned int i; 2065 2066 if (!attrs) 2067 return; 2068 2069 for (i = 0; i < attrs->n_assignments; i++) 2070 kfree(attrs->assignment_str[i]); 2071 2072 for (i = 0; i < attrs->n_actions; i++) 2073 kfree(attrs->action_str[i]); 2074 2075 kfree(attrs->name); 2076 kfree(attrs->sort_key_str); 2077 kfree(attrs->keys_str); 2078 kfree(attrs->vals_str); 2079 kfree(attrs->clock); 2080 kfree(attrs); 2081 } 2082 2083 static int parse_action(char *str, struct hist_trigger_attrs *attrs) 2084 { 2085 int ret = -EINVAL; 2086 2087 if (attrs->n_actions >= HIST_ACTIONS_MAX) 2088 return ret; 2089 2090 if ((str_has_prefix(str, "onmatch(")) || 2091 (str_has_prefix(str, "onmax(")) || 2092 (str_has_prefix(str, "onchange("))) { 2093 attrs->action_str[attrs->n_actions] = kstrdup(str, GFP_KERNEL); 2094 if (!attrs->action_str[attrs->n_actions]) { 2095 ret = -ENOMEM; 2096 return ret; 2097 } 2098 attrs->n_actions++; 2099 ret = 0; 2100 } 2101 return ret; 2102 } 2103 2104 static int parse_assignment(struct trace_array *tr, 2105 char *str, struct hist_trigger_attrs *attrs) 2106 { 2107 int len, ret = 0; 2108 2109 if ((len = str_has_prefix(str, "key=")) || 2110 (len = str_has_prefix(str, "keys="))) { 2111 attrs->keys_str = kstrdup(str + len, GFP_KERNEL); 2112 if (!attrs->keys_str) { 2113 ret = -ENOMEM; 2114 goto out; 2115 } 2116 } else if ((len = str_has_prefix(str, "val=")) || 2117 (len = str_has_prefix(str, "vals=")) || 2118 (len = str_has_prefix(str, "values="))) { 2119 attrs->vals_str = kstrdup(str + len, GFP_KERNEL); 2120 if (!attrs->vals_str) { 2121 ret = -ENOMEM; 2122 goto out; 2123 } 2124 } else if ((len = str_has_prefix(str, "sort="))) { 2125 attrs->sort_key_str = kstrdup(str + len, GFP_KERNEL); 2126 if (!attrs->sort_key_str) { 2127 ret = -ENOMEM; 2128 goto out; 2129 } 2130 } else if (str_has_prefix(str, "name=")) { 2131 attrs->name = kstrdup(str, GFP_KERNEL); 2132 if (!attrs->name) { 2133 ret = -ENOMEM; 2134 goto out; 2135 } 2136 } else if ((len = str_has_prefix(str, "clock="))) { 2137 str += len; 2138 2139 str = strstrip(str); 2140 attrs->clock = kstrdup(str, GFP_KERNEL); 2141 if (!attrs->clock) { 2142 ret = -ENOMEM; 2143 goto out; 2144 } 2145 } else if ((len = str_has_prefix(str, "size="))) { 2146 int map_bits = parse_map_size(str + len); 2147 2148 if (map_bits < 0) { 2149 ret = map_bits; 2150 goto out; 2151 } 2152 attrs->map_bits = map_bits; 2153 } else { 2154 char *assignment; 2155 2156 if (attrs->n_assignments == TRACING_MAP_VARS_MAX) { 2157 hist_err(tr, HIST_ERR_TOO_MANY_VARS, errpos(str)); 2158 ret = -EINVAL; 2159 goto out; 2160 } 2161 2162 assignment = kstrdup(str, GFP_KERNEL); 2163 if (!assignment) { 2164 ret = -ENOMEM; 2165 goto out; 2166 } 2167 2168 attrs->assignment_str[attrs->n_assignments++] = assignment; 2169 } 2170 out: 2171 return ret; 2172 } 2173 2174 static struct hist_trigger_attrs * 2175 parse_hist_trigger_attrs(struct trace_array *tr, char *trigger_str) 2176 { 2177 struct hist_trigger_attrs *attrs; 2178 int ret = 0; 2179 2180 attrs = kzalloc(sizeof(*attrs), GFP_KERNEL); 2181 if (!attrs) 2182 return ERR_PTR(-ENOMEM); 2183 2184 while (trigger_str) { 2185 char *str = strsep(&trigger_str, ":"); 2186 char *rhs; 2187 2188 rhs = strchr(str, '='); 2189 if (rhs) { 2190 if (!strlen(++rhs)) { 2191 ret = -EINVAL; 2192 hist_err(tr, HIST_ERR_EMPTY_ASSIGNMENT, errpos(str)); 2193 goto free; 2194 } 2195 ret = parse_assignment(tr, str, attrs); 2196 if (ret) 2197 goto free; 2198 } else if (strcmp(str, "pause") == 0) 2199 attrs->pause = true; 2200 else if ((strcmp(str, "cont") == 0) || 2201 (strcmp(str, "continue") == 0)) 2202 attrs->cont = true; 2203 else if (strcmp(str, "clear") == 0) 2204 attrs->clear = true; 2205 else { 2206 ret = parse_action(str, attrs); 2207 if (ret) 2208 goto free; 2209 } 2210 } 2211 2212 if (!attrs->keys_str) { 2213 ret = -EINVAL; 2214 goto free; 2215 } 2216 2217 if (!attrs->clock) { 2218 attrs->clock = kstrdup("global", GFP_KERNEL); 2219 if (!attrs->clock) { 2220 ret = -ENOMEM; 2221 goto free; 2222 } 2223 } 2224 2225 return attrs; 2226 free: 2227 destroy_hist_trigger_attrs(attrs); 2228 2229 return ERR_PTR(ret); 2230 } 2231 2232 static inline void save_comm(char *comm, struct task_struct *task) 2233 { 2234 if (!task->pid) { 2235 strcpy(comm, "<idle>"); 2236 return; 2237 } 2238 2239 if (WARN_ON_ONCE(task->pid < 0)) { 2240 strcpy(comm, "<XXX>"); 2241 return; 2242 } 2243 2244 strncpy(comm, task->comm, TASK_COMM_LEN); 2245 } 2246 2247 static void hist_elt_data_free(struct hist_elt_data *elt_data) 2248 { 2249 unsigned int i; 2250 2251 for (i = 0; i < SYNTH_FIELDS_MAX; i++) 2252 kfree(elt_data->field_var_str[i]); 2253 2254 kfree(elt_data->comm); 2255 kfree(elt_data); 2256 } 2257 2258 static void hist_trigger_elt_data_free(struct tracing_map_elt *elt) 2259 { 2260 struct hist_elt_data *elt_data = elt->private_data; 2261 2262 hist_elt_data_free(elt_data); 2263 } 2264 2265 static int hist_trigger_elt_data_alloc(struct tracing_map_elt *elt) 2266 { 2267 struct hist_trigger_data *hist_data = elt->map->private_data; 2268 unsigned int size = TASK_COMM_LEN; 2269 struct hist_elt_data *elt_data; 2270 struct hist_field *key_field; 2271 unsigned int i, n_str; 2272 2273 elt_data = kzalloc(sizeof(*elt_data), GFP_KERNEL); 2274 if (!elt_data) 2275 return -ENOMEM; 2276 2277 for_each_hist_key_field(i, hist_data) { 2278 key_field = hist_data->fields[i]; 2279 2280 if (key_field->flags & HIST_FIELD_FL_EXECNAME) { 2281 elt_data->comm = kzalloc(size, GFP_KERNEL); 2282 if (!elt_data->comm) { 2283 kfree(elt_data); 2284 return -ENOMEM; 2285 } 2286 break; 2287 } 2288 } 2289 2290 n_str = hist_data->n_field_var_str + hist_data->n_save_var_str; 2291 2292 size = STR_VAR_LEN_MAX; 2293 2294 for (i = 0; i < n_str; i++) { 2295 elt_data->field_var_str[i] = kzalloc(size, GFP_KERNEL); 2296 if (!elt_data->field_var_str[i]) { 2297 hist_elt_data_free(elt_data); 2298 return -ENOMEM; 2299 } 2300 } 2301 2302 elt->private_data = elt_data; 2303 2304 return 0; 2305 } 2306 2307 static void hist_trigger_elt_data_init(struct tracing_map_elt *elt) 2308 { 2309 struct hist_elt_data *elt_data = elt->private_data; 2310 2311 if (elt_data->comm) 2312 save_comm(elt_data->comm, current); 2313 } 2314 2315 static const struct tracing_map_ops hist_trigger_elt_data_ops = { 2316 .elt_alloc = hist_trigger_elt_data_alloc, 2317 .elt_free = hist_trigger_elt_data_free, 2318 .elt_init = hist_trigger_elt_data_init, 2319 }; 2320 2321 static const char *get_hist_field_flags(struct hist_field *hist_field) 2322 { 2323 const char *flags_str = NULL; 2324 2325 if (hist_field->flags & HIST_FIELD_FL_HEX) 2326 flags_str = "hex"; 2327 else if (hist_field->flags & HIST_FIELD_FL_SYM) 2328 flags_str = "sym"; 2329 else if (hist_field->flags & HIST_FIELD_FL_SYM_OFFSET) 2330 flags_str = "sym-offset"; 2331 else if (hist_field->flags & HIST_FIELD_FL_EXECNAME) 2332 flags_str = "execname"; 2333 else if (hist_field->flags & HIST_FIELD_FL_SYSCALL) 2334 flags_str = "syscall"; 2335 else if (hist_field->flags & HIST_FIELD_FL_LOG2) 2336 flags_str = "log2"; 2337 else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP_USECS) 2338 flags_str = "usecs"; 2339 2340 return flags_str; 2341 } 2342 2343 static void expr_field_str(struct hist_field *field, char *expr) 2344 { 2345 if (field->flags & HIST_FIELD_FL_VAR_REF) 2346 strcat(expr, "$"); 2347 2348 strcat(expr, hist_field_name(field, 0)); 2349 2350 if (field->flags && !(field->flags & HIST_FIELD_FL_VAR_REF)) { 2351 const char *flags_str = get_hist_field_flags(field); 2352 2353 if (flags_str) { 2354 strcat(expr, "."); 2355 strcat(expr, flags_str); 2356 } 2357 } 2358 } 2359 2360 static char *expr_str(struct hist_field *field, unsigned int level) 2361 { 2362 char *expr; 2363 2364 if (level > 1) 2365 return NULL; 2366 2367 expr = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL); 2368 if (!expr) 2369 return NULL; 2370 2371 if (!field->operands[0]) { 2372 expr_field_str(field, expr); 2373 return expr; 2374 } 2375 2376 if (field->operator == FIELD_OP_UNARY_MINUS) { 2377 char *subexpr; 2378 2379 strcat(expr, "-("); 2380 subexpr = expr_str(field->operands[0], ++level); 2381 if (!subexpr) { 2382 kfree(expr); 2383 return NULL; 2384 } 2385 strcat(expr, subexpr); 2386 strcat(expr, ")"); 2387 2388 kfree(subexpr); 2389 2390 return expr; 2391 } 2392 2393 expr_field_str(field->operands[0], expr); 2394 2395 switch (field->operator) { 2396 case FIELD_OP_MINUS: 2397 strcat(expr, "-"); 2398 break; 2399 case FIELD_OP_PLUS: 2400 strcat(expr, "+"); 2401 break; 2402 default: 2403 kfree(expr); 2404 return NULL; 2405 } 2406 2407 expr_field_str(field->operands[1], expr); 2408 2409 return expr; 2410 } 2411 2412 static int contains_operator(char *str) 2413 { 2414 enum field_op_id field_op = FIELD_OP_NONE; 2415 char *op; 2416 2417 op = strpbrk(str, "+-"); 2418 if (!op) 2419 return FIELD_OP_NONE; 2420 2421 switch (*op) { 2422 case '-': 2423 if (*str == '-') 2424 field_op = FIELD_OP_UNARY_MINUS; 2425 else 2426 field_op = FIELD_OP_MINUS; 2427 break; 2428 case '+': 2429 field_op = FIELD_OP_PLUS; 2430 break; 2431 default: 2432 break; 2433 } 2434 2435 return field_op; 2436 } 2437 2438 static void __destroy_hist_field(struct hist_field *hist_field) 2439 { 2440 kfree(hist_field->var.name); 2441 kfree(hist_field->name); 2442 kfree(hist_field->type); 2443 2444 kfree(hist_field); 2445 } 2446 2447 static void destroy_hist_field(struct hist_field *hist_field, 2448 unsigned int level) 2449 { 2450 unsigned int i; 2451 2452 if (level > 3) 2453 return; 2454 2455 if (!hist_field) 2456 return; 2457 2458 if (hist_field->flags & HIST_FIELD_FL_VAR_REF) 2459 return; /* var refs will be destroyed separately */ 2460 2461 for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++) 2462 destroy_hist_field(hist_field->operands[i], level + 1); 2463 2464 __destroy_hist_field(hist_field); 2465 } 2466 2467 static struct hist_field *create_hist_field(struct hist_trigger_data *hist_data, 2468 struct ftrace_event_field *field, 2469 unsigned long flags, 2470 char *var_name) 2471 { 2472 struct hist_field *hist_field; 2473 2474 if (field && is_function_field(field)) 2475 return NULL; 2476 2477 hist_field = kzalloc(sizeof(struct hist_field), GFP_KERNEL); 2478 if (!hist_field) 2479 return NULL; 2480 2481 hist_field->hist_data = hist_data; 2482 2483 if (flags & HIST_FIELD_FL_EXPR || flags & HIST_FIELD_FL_ALIAS) 2484 goto out; /* caller will populate */ 2485 2486 if (flags & HIST_FIELD_FL_VAR_REF) { 2487 hist_field->fn = hist_field_var_ref; 2488 goto out; 2489 } 2490 2491 if (flags & HIST_FIELD_FL_HITCOUNT) { 2492 hist_field->fn = hist_field_counter; 2493 hist_field->size = sizeof(u64); 2494 hist_field->type = kstrdup("u64", GFP_KERNEL); 2495 if (!hist_field->type) 2496 goto free; 2497 goto out; 2498 } 2499 2500 if (flags & HIST_FIELD_FL_STACKTRACE) { 2501 hist_field->fn = hist_field_none; 2502 goto out; 2503 } 2504 2505 if (flags & HIST_FIELD_FL_LOG2) { 2506 unsigned long fl = flags & ~HIST_FIELD_FL_LOG2; 2507 hist_field->fn = hist_field_log2; 2508 hist_field->operands[0] = create_hist_field(hist_data, field, fl, NULL); 2509 hist_field->size = hist_field->operands[0]->size; 2510 hist_field->type = kstrdup(hist_field->operands[0]->type, GFP_KERNEL); 2511 if (!hist_field->type) 2512 goto free; 2513 goto out; 2514 } 2515 2516 if (flags & HIST_FIELD_FL_TIMESTAMP) { 2517 hist_field->fn = hist_field_timestamp; 2518 hist_field->size = sizeof(u64); 2519 hist_field->type = kstrdup("u64", GFP_KERNEL); 2520 if (!hist_field->type) 2521 goto free; 2522 goto out; 2523 } 2524 2525 if (flags & HIST_FIELD_FL_CPU) { 2526 hist_field->fn = hist_field_cpu; 2527 hist_field->size = sizeof(int); 2528 hist_field->type = kstrdup("unsigned int", GFP_KERNEL); 2529 if (!hist_field->type) 2530 goto free; 2531 goto out; 2532 } 2533 2534 if (WARN_ON_ONCE(!field)) 2535 goto out; 2536 2537 if (is_string_field(field)) { 2538 flags |= HIST_FIELD_FL_STRING; 2539 2540 hist_field->size = MAX_FILTER_STR_VAL; 2541 hist_field->type = kstrdup(field->type, GFP_KERNEL); 2542 if (!hist_field->type) 2543 goto free; 2544 2545 if (field->filter_type == FILTER_STATIC_STRING) 2546 hist_field->fn = hist_field_string; 2547 else if (field->filter_type == FILTER_DYN_STRING) 2548 hist_field->fn = hist_field_dynstring; 2549 else 2550 hist_field->fn = hist_field_pstring; 2551 } else { 2552 hist_field->size = field->size; 2553 hist_field->is_signed = field->is_signed; 2554 hist_field->type = kstrdup(field->type, GFP_KERNEL); 2555 if (!hist_field->type) 2556 goto free; 2557 2558 hist_field->fn = select_value_fn(field->size, 2559 field->is_signed); 2560 if (!hist_field->fn) { 2561 destroy_hist_field(hist_field, 0); 2562 return NULL; 2563 } 2564 } 2565 out: 2566 hist_field->field = field; 2567 hist_field->flags = flags; 2568 2569 if (var_name) { 2570 hist_field->var.name = kstrdup(var_name, GFP_KERNEL); 2571 if (!hist_field->var.name) 2572 goto free; 2573 } 2574 2575 return hist_field; 2576 free: 2577 destroy_hist_field(hist_field, 0); 2578 return NULL; 2579 } 2580 2581 static void destroy_hist_fields(struct hist_trigger_data *hist_data) 2582 { 2583 unsigned int i; 2584 2585 for (i = 0; i < HIST_FIELDS_MAX; i++) { 2586 if (hist_data->fields[i]) { 2587 destroy_hist_field(hist_data->fields[i], 0); 2588 hist_data->fields[i] = NULL; 2589 } 2590 } 2591 2592 for (i = 0; i < hist_data->n_var_refs; i++) { 2593 WARN_ON(!(hist_data->var_refs[i]->flags & HIST_FIELD_FL_VAR_REF)); 2594 __destroy_hist_field(hist_data->var_refs[i]); 2595 hist_data->var_refs[i] = NULL; 2596 } 2597 } 2598 2599 static int init_var_ref(struct hist_field *ref_field, 2600 struct hist_field *var_field, 2601 char *system, char *event_name) 2602 { 2603 int err = 0; 2604 2605 ref_field->var.idx = var_field->var.idx; 2606 ref_field->var.hist_data = var_field->hist_data; 2607 ref_field->size = var_field->size; 2608 ref_field->is_signed = var_field->is_signed; 2609 ref_field->flags |= var_field->flags & 2610 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS); 2611 2612 if (system) { 2613 ref_field->system = kstrdup(system, GFP_KERNEL); 2614 if (!ref_field->system) 2615 return -ENOMEM; 2616 } 2617 2618 if (event_name) { 2619 ref_field->event_name = kstrdup(event_name, GFP_KERNEL); 2620 if (!ref_field->event_name) { 2621 err = -ENOMEM; 2622 goto free; 2623 } 2624 } 2625 2626 if (var_field->var.name) { 2627 ref_field->name = kstrdup(var_field->var.name, GFP_KERNEL); 2628 if (!ref_field->name) { 2629 err = -ENOMEM; 2630 goto free; 2631 } 2632 } else if (var_field->name) { 2633 ref_field->name = kstrdup(var_field->name, GFP_KERNEL); 2634 if (!ref_field->name) { 2635 err = -ENOMEM; 2636 goto free; 2637 } 2638 } 2639 2640 ref_field->type = kstrdup(var_field->type, GFP_KERNEL); 2641 if (!ref_field->type) { 2642 err = -ENOMEM; 2643 goto free; 2644 } 2645 out: 2646 return err; 2647 free: 2648 kfree(ref_field->system); 2649 kfree(ref_field->event_name); 2650 kfree(ref_field->name); 2651 2652 goto out; 2653 } 2654 2655 /** 2656 * create_var_ref - Create a variable reference and attach it to trigger 2657 * @hist_data: The trigger that will be referencing the variable 2658 * @var_field: The VAR field to create a reference to 2659 * @system: The optional system string 2660 * @event_name: The optional event_name string 2661 * 2662 * Given a variable hist_field, create a VAR_REF hist_field that 2663 * represents a reference to it. 2664 * 2665 * This function also adds the reference to the trigger that 2666 * now references the variable. 2667 * 2668 * Return: The VAR_REF field if successful, NULL if not 2669 */ 2670 static struct hist_field *create_var_ref(struct hist_trigger_data *hist_data, 2671 struct hist_field *var_field, 2672 char *system, char *event_name) 2673 { 2674 unsigned long flags = HIST_FIELD_FL_VAR_REF; 2675 struct hist_field *ref_field; 2676 2677 ref_field = create_hist_field(var_field->hist_data, NULL, flags, NULL); 2678 if (ref_field) { 2679 if (init_var_ref(ref_field, var_field, system, event_name)) { 2680 destroy_hist_field(ref_field, 0); 2681 return NULL; 2682 } 2683 2684 hist_data->var_refs[hist_data->n_var_refs] = ref_field; 2685 ref_field->var_ref_idx = hist_data->n_var_refs++; 2686 } 2687 2688 return ref_field; 2689 } 2690 2691 static bool is_var_ref(char *var_name) 2692 { 2693 if (!var_name || strlen(var_name) < 2 || var_name[0] != '$') 2694 return false; 2695 2696 return true; 2697 } 2698 2699 static char *field_name_from_var(struct hist_trigger_data *hist_data, 2700 char *var_name) 2701 { 2702 char *name, *field; 2703 unsigned int i; 2704 2705 for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) { 2706 name = hist_data->attrs->var_defs.name[i]; 2707 2708 if (strcmp(var_name, name) == 0) { 2709 field = hist_data->attrs->var_defs.expr[i]; 2710 if (contains_operator(field) || is_var_ref(field)) 2711 continue; 2712 return field; 2713 } 2714 } 2715 2716 return NULL; 2717 } 2718 2719 static char *local_field_var_ref(struct hist_trigger_data *hist_data, 2720 char *system, char *event_name, 2721 char *var_name) 2722 { 2723 struct trace_event_call *call; 2724 2725 if (system && event_name) { 2726 call = hist_data->event_file->event_call; 2727 2728 if (strcmp(system, call->class->system) != 0) 2729 return NULL; 2730 2731 if (strcmp(event_name, trace_event_name(call)) != 0) 2732 return NULL; 2733 } 2734 2735 if (!!system != !!event_name) 2736 return NULL; 2737 2738 if (!is_var_ref(var_name)) 2739 return NULL; 2740 2741 var_name++; 2742 2743 return field_name_from_var(hist_data, var_name); 2744 } 2745 2746 static struct hist_field *parse_var_ref(struct hist_trigger_data *hist_data, 2747 char *system, char *event_name, 2748 char *var_name) 2749 { 2750 struct hist_field *var_field = NULL, *ref_field = NULL; 2751 struct trace_array *tr = hist_data->event_file->tr; 2752 2753 if (!is_var_ref(var_name)) 2754 return NULL; 2755 2756 var_name++; 2757 2758 var_field = find_event_var(hist_data, system, event_name, var_name); 2759 if (var_field) 2760 ref_field = create_var_ref(hist_data, var_field, 2761 system, event_name); 2762 2763 if (!ref_field) 2764 hist_err(tr, HIST_ERR_VAR_NOT_FOUND, errpos(var_name)); 2765 2766 return ref_field; 2767 } 2768 2769 static struct ftrace_event_field * 2770 parse_field(struct hist_trigger_data *hist_data, struct trace_event_file *file, 2771 char *field_str, unsigned long *flags) 2772 { 2773 struct ftrace_event_field *field = NULL; 2774 char *field_name, *modifier, *str; 2775 struct trace_array *tr = file->tr; 2776 2777 modifier = str = kstrdup(field_str, GFP_KERNEL); 2778 if (!modifier) 2779 return ERR_PTR(-ENOMEM); 2780 2781 field_name = strsep(&modifier, "."); 2782 if (modifier) { 2783 if (strcmp(modifier, "hex") == 0) 2784 *flags |= HIST_FIELD_FL_HEX; 2785 else if (strcmp(modifier, "sym") == 0) 2786 *flags |= HIST_FIELD_FL_SYM; 2787 else if (strcmp(modifier, "sym-offset") == 0) 2788 *flags |= HIST_FIELD_FL_SYM_OFFSET; 2789 else if ((strcmp(modifier, "execname") == 0) && 2790 (strcmp(field_name, "common_pid") == 0)) 2791 *flags |= HIST_FIELD_FL_EXECNAME; 2792 else if (strcmp(modifier, "syscall") == 0) 2793 *flags |= HIST_FIELD_FL_SYSCALL; 2794 else if (strcmp(modifier, "log2") == 0) 2795 *flags |= HIST_FIELD_FL_LOG2; 2796 else if (strcmp(modifier, "usecs") == 0) 2797 *flags |= HIST_FIELD_FL_TIMESTAMP_USECS; 2798 else { 2799 hist_err(tr, HIST_ERR_BAD_FIELD_MODIFIER, errpos(modifier)); 2800 field = ERR_PTR(-EINVAL); 2801 goto out; 2802 } 2803 } 2804 2805 if (strcmp(field_name, "common_timestamp") == 0) { 2806 *flags |= HIST_FIELD_FL_TIMESTAMP; 2807 hist_data->enable_timestamps = true; 2808 if (*flags & HIST_FIELD_FL_TIMESTAMP_USECS) 2809 hist_data->attrs->ts_in_usecs = true; 2810 } else if (strcmp(field_name, "cpu") == 0) 2811 *flags |= HIST_FIELD_FL_CPU; 2812 else { 2813 field = trace_find_event_field(file->event_call, field_name); 2814 if (!field || !field->size) { 2815 hist_err(tr, HIST_ERR_FIELD_NOT_FOUND, errpos(field_name)); 2816 field = ERR_PTR(-EINVAL); 2817 goto out; 2818 } 2819 } 2820 out: 2821 kfree(str); 2822 2823 return field; 2824 } 2825 2826 static struct hist_field *create_alias(struct hist_trigger_data *hist_data, 2827 struct hist_field *var_ref, 2828 char *var_name) 2829 { 2830 struct hist_field *alias = NULL; 2831 unsigned long flags = HIST_FIELD_FL_ALIAS | HIST_FIELD_FL_VAR; 2832 2833 alias = create_hist_field(hist_data, NULL, flags, var_name); 2834 if (!alias) 2835 return NULL; 2836 2837 alias->fn = var_ref->fn; 2838 alias->operands[0] = var_ref; 2839 2840 if (init_var_ref(alias, var_ref, var_ref->system, var_ref->event_name)) { 2841 destroy_hist_field(alias, 0); 2842 return NULL; 2843 } 2844 2845 alias->var_ref_idx = var_ref->var_ref_idx; 2846 2847 return alias; 2848 } 2849 2850 static struct hist_field *parse_atom(struct hist_trigger_data *hist_data, 2851 struct trace_event_file *file, char *str, 2852 unsigned long *flags, char *var_name) 2853 { 2854 char *s, *ref_system = NULL, *ref_event = NULL, *ref_var = str; 2855 struct ftrace_event_field *field = NULL; 2856 struct hist_field *hist_field = NULL; 2857 int ret = 0; 2858 2859 s = strchr(str, '.'); 2860 if (s) { 2861 s = strchr(++s, '.'); 2862 if (s) { 2863 ref_system = strsep(&str, "."); 2864 if (!str) { 2865 ret = -EINVAL; 2866 goto out; 2867 } 2868 ref_event = strsep(&str, "."); 2869 if (!str) { 2870 ret = -EINVAL; 2871 goto out; 2872 } 2873 ref_var = str; 2874 } 2875 } 2876 2877 s = local_field_var_ref(hist_data, ref_system, ref_event, ref_var); 2878 if (!s) { 2879 hist_field = parse_var_ref(hist_data, ref_system, 2880 ref_event, ref_var); 2881 if (hist_field) { 2882 if (var_name) { 2883 hist_field = create_alias(hist_data, hist_field, var_name); 2884 if (!hist_field) { 2885 ret = -ENOMEM; 2886 goto out; 2887 } 2888 } 2889 return hist_field; 2890 } 2891 } else 2892 str = s; 2893 2894 field = parse_field(hist_data, file, str, flags); 2895 if (IS_ERR(field)) { 2896 ret = PTR_ERR(field); 2897 goto out; 2898 } 2899 2900 hist_field = create_hist_field(hist_data, field, *flags, var_name); 2901 if (!hist_field) { 2902 ret = -ENOMEM; 2903 goto out; 2904 } 2905 2906 return hist_field; 2907 out: 2908 return ERR_PTR(ret); 2909 } 2910 2911 static struct hist_field *parse_expr(struct hist_trigger_data *hist_data, 2912 struct trace_event_file *file, 2913 char *str, unsigned long flags, 2914 char *var_name, unsigned int level); 2915 2916 static struct hist_field *parse_unary(struct hist_trigger_data *hist_data, 2917 struct trace_event_file *file, 2918 char *str, unsigned long flags, 2919 char *var_name, unsigned int level) 2920 { 2921 struct hist_field *operand1, *expr = NULL; 2922 unsigned long operand_flags; 2923 int ret = 0; 2924 char *s; 2925 2926 /* we support only -(xxx) i.e. explicit parens required */ 2927 2928 if (level > 3) { 2929 hist_err(file->tr, HIST_ERR_TOO_MANY_SUBEXPR, errpos(str)); 2930 ret = -EINVAL; 2931 goto free; 2932 } 2933 2934 str++; /* skip leading '-' */ 2935 2936 s = strchr(str, '('); 2937 if (s) 2938 str++; 2939 else { 2940 ret = -EINVAL; 2941 goto free; 2942 } 2943 2944 s = strrchr(str, ')'); 2945 if (s) 2946 *s = '\0'; 2947 else { 2948 ret = -EINVAL; /* no closing ')' */ 2949 goto free; 2950 } 2951 2952 flags |= HIST_FIELD_FL_EXPR; 2953 expr = create_hist_field(hist_data, NULL, flags, var_name); 2954 if (!expr) { 2955 ret = -ENOMEM; 2956 goto free; 2957 } 2958 2959 operand_flags = 0; 2960 operand1 = parse_expr(hist_data, file, str, operand_flags, NULL, ++level); 2961 if (IS_ERR(operand1)) { 2962 ret = PTR_ERR(operand1); 2963 goto free; 2964 } 2965 2966 expr->flags |= operand1->flags & 2967 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS); 2968 expr->fn = hist_field_unary_minus; 2969 expr->operands[0] = operand1; 2970 expr->operator = FIELD_OP_UNARY_MINUS; 2971 expr->name = expr_str(expr, 0); 2972 expr->type = kstrdup(operand1->type, GFP_KERNEL); 2973 if (!expr->type) { 2974 ret = -ENOMEM; 2975 goto free; 2976 } 2977 2978 return expr; 2979 free: 2980 destroy_hist_field(expr, 0); 2981 return ERR_PTR(ret); 2982 } 2983 2984 static int check_expr_operands(struct trace_array *tr, 2985 struct hist_field *operand1, 2986 struct hist_field *operand2) 2987 { 2988 unsigned long operand1_flags = operand1->flags; 2989 unsigned long operand2_flags = operand2->flags; 2990 2991 if ((operand1_flags & HIST_FIELD_FL_VAR_REF) || 2992 (operand1_flags & HIST_FIELD_FL_ALIAS)) { 2993 struct hist_field *var; 2994 2995 var = find_var_field(operand1->var.hist_data, operand1->name); 2996 if (!var) 2997 return -EINVAL; 2998 operand1_flags = var->flags; 2999 } 3000 3001 if ((operand2_flags & HIST_FIELD_FL_VAR_REF) || 3002 (operand2_flags & HIST_FIELD_FL_ALIAS)) { 3003 struct hist_field *var; 3004 3005 var = find_var_field(operand2->var.hist_data, operand2->name); 3006 if (!var) 3007 return -EINVAL; 3008 operand2_flags = var->flags; 3009 } 3010 3011 if ((operand1_flags & HIST_FIELD_FL_TIMESTAMP_USECS) != 3012 (operand2_flags & HIST_FIELD_FL_TIMESTAMP_USECS)) { 3013 hist_err(tr, HIST_ERR_TIMESTAMP_MISMATCH, 0); 3014 return -EINVAL; 3015 } 3016 3017 return 0; 3018 } 3019 3020 static struct hist_field *parse_expr(struct hist_trigger_data *hist_data, 3021 struct trace_event_file *file, 3022 char *str, unsigned long flags, 3023 char *var_name, unsigned int level) 3024 { 3025 struct hist_field *operand1 = NULL, *operand2 = NULL, *expr = NULL; 3026 unsigned long operand_flags; 3027 int field_op, ret = -EINVAL; 3028 char *sep, *operand1_str; 3029 3030 if (level > 3) { 3031 hist_err(file->tr, HIST_ERR_TOO_MANY_SUBEXPR, errpos(str)); 3032 return ERR_PTR(-EINVAL); 3033 } 3034 3035 field_op = contains_operator(str); 3036 3037 if (field_op == FIELD_OP_NONE) 3038 return parse_atom(hist_data, file, str, &flags, var_name); 3039 3040 if (field_op == FIELD_OP_UNARY_MINUS) 3041 return parse_unary(hist_data, file, str, flags, var_name, ++level); 3042 3043 switch (field_op) { 3044 case FIELD_OP_MINUS: 3045 sep = "-"; 3046 break; 3047 case FIELD_OP_PLUS: 3048 sep = "+"; 3049 break; 3050 default: 3051 goto free; 3052 } 3053 3054 operand1_str = strsep(&str, sep); 3055 if (!operand1_str || !str) 3056 goto free; 3057 3058 operand_flags = 0; 3059 operand1 = parse_atom(hist_data, file, operand1_str, 3060 &operand_flags, NULL); 3061 if (IS_ERR(operand1)) { 3062 ret = PTR_ERR(operand1); 3063 operand1 = NULL; 3064 goto free; 3065 } 3066 3067 /* rest of string could be another expression e.g. b+c in a+b+c */ 3068 operand_flags = 0; 3069 operand2 = parse_expr(hist_data, file, str, operand_flags, NULL, ++level); 3070 if (IS_ERR(operand2)) { 3071 ret = PTR_ERR(operand2); 3072 operand2 = NULL; 3073 goto free; 3074 } 3075 3076 ret = check_expr_operands(file->tr, operand1, operand2); 3077 if (ret) 3078 goto free; 3079 3080 flags |= HIST_FIELD_FL_EXPR; 3081 3082 flags |= operand1->flags & 3083 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS); 3084 3085 expr = create_hist_field(hist_data, NULL, flags, var_name); 3086 if (!expr) { 3087 ret = -ENOMEM; 3088 goto free; 3089 } 3090 3091 operand1->read_once = true; 3092 operand2->read_once = true; 3093 3094 expr->operands[0] = operand1; 3095 expr->operands[1] = operand2; 3096 expr->operator = field_op; 3097 expr->name = expr_str(expr, 0); 3098 expr->type = kstrdup(operand1->type, GFP_KERNEL); 3099 if (!expr->type) { 3100 ret = -ENOMEM; 3101 goto free; 3102 } 3103 3104 switch (field_op) { 3105 case FIELD_OP_MINUS: 3106 expr->fn = hist_field_minus; 3107 break; 3108 case FIELD_OP_PLUS: 3109 expr->fn = hist_field_plus; 3110 break; 3111 default: 3112 ret = -EINVAL; 3113 goto free; 3114 } 3115 3116 return expr; 3117 free: 3118 destroy_hist_field(operand1, 0); 3119 destroy_hist_field(operand2, 0); 3120 destroy_hist_field(expr, 0); 3121 3122 return ERR_PTR(ret); 3123 } 3124 3125 static char *find_trigger_filter(struct hist_trigger_data *hist_data, 3126 struct trace_event_file *file) 3127 { 3128 struct event_trigger_data *test; 3129 3130 lockdep_assert_held(&event_mutex); 3131 3132 list_for_each_entry(test, &file->triggers, list) { 3133 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 3134 if (test->private_data == hist_data) 3135 return test->filter_str; 3136 } 3137 } 3138 3139 return NULL; 3140 } 3141 3142 static struct event_command trigger_hist_cmd; 3143 static int event_hist_trigger_func(struct event_command *cmd_ops, 3144 struct trace_event_file *file, 3145 char *glob, char *cmd, char *param); 3146 3147 static bool compatible_keys(struct hist_trigger_data *target_hist_data, 3148 struct hist_trigger_data *hist_data, 3149 unsigned int n_keys) 3150 { 3151 struct hist_field *target_hist_field, *hist_field; 3152 unsigned int n, i, j; 3153 3154 if (hist_data->n_fields - hist_data->n_vals != n_keys) 3155 return false; 3156 3157 i = hist_data->n_vals; 3158 j = target_hist_data->n_vals; 3159 3160 for (n = 0; n < n_keys; n++) { 3161 hist_field = hist_data->fields[i + n]; 3162 target_hist_field = target_hist_data->fields[j + n]; 3163 3164 if (strcmp(hist_field->type, target_hist_field->type) != 0) 3165 return false; 3166 if (hist_field->size != target_hist_field->size) 3167 return false; 3168 if (hist_field->is_signed != target_hist_field->is_signed) 3169 return false; 3170 } 3171 3172 return true; 3173 } 3174 3175 static struct hist_trigger_data * 3176 find_compatible_hist(struct hist_trigger_data *target_hist_data, 3177 struct trace_event_file *file) 3178 { 3179 struct hist_trigger_data *hist_data; 3180 struct event_trigger_data *test; 3181 unsigned int n_keys; 3182 3183 lockdep_assert_held(&event_mutex); 3184 3185 n_keys = target_hist_data->n_fields - target_hist_data->n_vals; 3186 3187 list_for_each_entry(test, &file->triggers, list) { 3188 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 3189 hist_data = test->private_data; 3190 3191 if (compatible_keys(target_hist_data, hist_data, n_keys)) 3192 return hist_data; 3193 } 3194 } 3195 3196 return NULL; 3197 } 3198 3199 static struct trace_event_file *event_file(struct trace_array *tr, 3200 char *system, char *event_name) 3201 { 3202 struct trace_event_file *file; 3203 3204 file = __find_event_file(tr, system, event_name); 3205 if (!file) 3206 return ERR_PTR(-EINVAL); 3207 3208 return file; 3209 } 3210 3211 static struct hist_field * 3212 find_synthetic_field_var(struct hist_trigger_data *target_hist_data, 3213 char *system, char *event_name, char *field_name) 3214 { 3215 struct hist_field *event_var; 3216 char *synthetic_name; 3217 3218 synthetic_name = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL); 3219 if (!synthetic_name) 3220 return ERR_PTR(-ENOMEM); 3221 3222 strcpy(synthetic_name, "synthetic_"); 3223 strcat(synthetic_name, field_name); 3224 3225 event_var = find_event_var(target_hist_data, system, event_name, synthetic_name); 3226 3227 kfree(synthetic_name); 3228 3229 return event_var; 3230 } 3231 3232 /** 3233 * create_field_var_hist - Automatically create a histogram and var for a field 3234 * @target_hist_data: The target hist trigger 3235 * @subsys_name: Optional subsystem name 3236 * @event_name: Optional event name 3237 * @field_name: The name of the field (and the resulting variable) 3238 * 3239 * Hist trigger actions fetch data from variables, not directly from 3240 * events. However, for convenience, users are allowed to directly 3241 * specify an event field in an action, which will be automatically 3242 * converted into a variable on their behalf. 3243 3244 * If a user specifies a field on an event that isn't the event the 3245 * histogram currently being defined (the target event histogram), the 3246 * only way that can be accomplished is if a new hist trigger is 3247 * created and the field variable defined on that. 3248 * 3249 * This function creates a new histogram compatible with the target 3250 * event (meaning a histogram with the same key as the target 3251 * histogram), and creates a variable for the specified field, but 3252 * with 'synthetic_' prepended to the variable name in order to avoid 3253 * collision with normal field variables. 3254 * 3255 * Return: The variable created for the field. 3256 */ 3257 static struct hist_field * 3258 create_field_var_hist(struct hist_trigger_data *target_hist_data, 3259 char *subsys_name, char *event_name, char *field_name) 3260 { 3261 struct trace_array *tr = target_hist_data->event_file->tr; 3262 struct hist_field *event_var = ERR_PTR(-EINVAL); 3263 struct hist_trigger_data *hist_data; 3264 unsigned int i, n, first = true; 3265 struct field_var_hist *var_hist; 3266 struct trace_event_file *file; 3267 struct hist_field *key_field; 3268 char *saved_filter; 3269 char *cmd; 3270 int ret; 3271 3272 if (target_hist_data->n_field_var_hists >= SYNTH_FIELDS_MAX) { 3273 hist_err(tr, HIST_ERR_TOO_MANY_FIELD_VARS, errpos(field_name)); 3274 return ERR_PTR(-EINVAL); 3275 } 3276 3277 file = event_file(tr, subsys_name, event_name); 3278 3279 if (IS_ERR(file)) { 3280 hist_err(tr, HIST_ERR_EVENT_FILE_NOT_FOUND, errpos(field_name)); 3281 ret = PTR_ERR(file); 3282 return ERR_PTR(ret); 3283 } 3284 3285 /* 3286 * Look for a histogram compatible with target. We'll use the 3287 * found histogram specification to create a new matching 3288 * histogram with our variable on it. target_hist_data is not 3289 * yet a registered histogram so we can't use that. 3290 */ 3291 hist_data = find_compatible_hist(target_hist_data, file); 3292 if (!hist_data) { 3293 hist_err(tr, HIST_ERR_HIST_NOT_FOUND, errpos(field_name)); 3294 return ERR_PTR(-EINVAL); 3295 } 3296 3297 /* See if a synthetic field variable has already been created */ 3298 event_var = find_synthetic_field_var(target_hist_data, subsys_name, 3299 event_name, field_name); 3300 if (!IS_ERR_OR_NULL(event_var)) 3301 return event_var; 3302 3303 var_hist = kzalloc(sizeof(*var_hist), GFP_KERNEL); 3304 if (!var_hist) 3305 return ERR_PTR(-ENOMEM); 3306 3307 cmd = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL); 3308 if (!cmd) { 3309 kfree(var_hist); 3310 return ERR_PTR(-ENOMEM); 3311 } 3312 3313 /* Use the same keys as the compatible histogram */ 3314 strcat(cmd, "keys="); 3315 3316 for_each_hist_key_field(i, hist_data) { 3317 key_field = hist_data->fields[i]; 3318 if (!first) 3319 strcat(cmd, ","); 3320 strcat(cmd, key_field->field->name); 3321 first = false; 3322 } 3323 3324 /* Create the synthetic field variable specification */ 3325 strcat(cmd, ":synthetic_"); 3326 strcat(cmd, field_name); 3327 strcat(cmd, "="); 3328 strcat(cmd, field_name); 3329 3330 /* Use the same filter as the compatible histogram */ 3331 saved_filter = find_trigger_filter(hist_data, file); 3332 if (saved_filter) { 3333 strcat(cmd, " if "); 3334 strcat(cmd, saved_filter); 3335 } 3336 3337 var_hist->cmd = kstrdup(cmd, GFP_KERNEL); 3338 if (!var_hist->cmd) { 3339 kfree(cmd); 3340 kfree(var_hist); 3341 return ERR_PTR(-ENOMEM); 3342 } 3343 3344 /* Save the compatible histogram information */ 3345 var_hist->hist_data = hist_data; 3346 3347 /* Create the new histogram with our variable */ 3348 ret = event_hist_trigger_func(&trigger_hist_cmd, file, 3349 "", "hist", cmd); 3350 if (ret) { 3351 kfree(cmd); 3352 kfree(var_hist->cmd); 3353 kfree(var_hist); 3354 hist_err(tr, HIST_ERR_HIST_CREATE_FAIL, errpos(field_name)); 3355 return ERR_PTR(ret); 3356 } 3357 3358 kfree(cmd); 3359 3360 /* If we can't find the variable, something went wrong */ 3361 event_var = find_synthetic_field_var(target_hist_data, subsys_name, 3362 event_name, field_name); 3363 if (IS_ERR_OR_NULL(event_var)) { 3364 kfree(var_hist->cmd); 3365 kfree(var_hist); 3366 hist_err(tr, HIST_ERR_SYNTH_VAR_NOT_FOUND, errpos(field_name)); 3367 return ERR_PTR(-EINVAL); 3368 } 3369 3370 n = target_hist_data->n_field_var_hists; 3371 target_hist_data->field_var_hists[n] = var_hist; 3372 target_hist_data->n_field_var_hists++; 3373 3374 return event_var; 3375 } 3376 3377 static struct hist_field * 3378 find_target_event_var(struct hist_trigger_data *hist_data, 3379 char *subsys_name, char *event_name, char *var_name) 3380 { 3381 struct trace_event_file *file = hist_data->event_file; 3382 struct hist_field *hist_field = NULL; 3383 3384 if (subsys_name) { 3385 struct trace_event_call *call; 3386 3387 if (!event_name) 3388 return NULL; 3389 3390 call = file->event_call; 3391 3392 if (strcmp(subsys_name, call->class->system) != 0) 3393 return NULL; 3394 3395 if (strcmp(event_name, trace_event_name(call)) != 0) 3396 return NULL; 3397 } 3398 3399 hist_field = find_var_field(hist_data, var_name); 3400 3401 return hist_field; 3402 } 3403 3404 static inline void __update_field_vars(struct tracing_map_elt *elt, 3405 struct ring_buffer_event *rbe, 3406 void *rec, 3407 struct field_var **field_vars, 3408 unsigned int n_field_vars, 3409 unsigned int field_var_str_start) 3410 { 3411 struct hist_elt_data *elt_data = elt->private_data; 3412 unsigned int i, j, var_idx; 3413 u64 var_val; 3414 3415 for (i = 0, j = field_var_str_start; i < n_field_vars; i++) { 3416 struct field_var *field_var = field_vars[i]; 3417 struct hist_field *var = field_var->var; 3418 struct hist_field *val = field_var->val; 3419 3420 var_val = val->fn(val, elt, rbe, rec); 3421 var_idx = var->var.idx; 3422 3423 if (val->flags & HIST_FIELD_FL_STRING) { 3424 char *str = elt_data->field_var_str[j++]; 3425 char *val_str = (char *)(uintptr_t)var_val; 3426 3427 strscpy(str, val_str, STR_VAR_LEN_MAX); 3428 var_val = (u64)(uintptr_t)str; 3429 } 3430 tracing_map_set_var(elt, var_idx, var_val); 3431 } 3432 } 3433 3434 static void update_field_vars(struct hist_trigger_data *hist_data, 3435 struct tracing_map_elt *elt, 3436 struct ring_buffer_event *rbe, 3437 void *rec) 3438 { 3439 __update_field_vars(elt, rbe, rec, hist_data->field_vars, 3440 hist_data->n_field_vars, 0); 3441 } 3442 3443 static void save_track_data_vars(struct hist_trigger_data *hist_data, 3444 struct tracing_map_elt *elt, void *rec, 3445 struct ring_buffer_event *rbe, void *key, 3446 struct action_data *data, u64 *var_ref_vals) 3447 { 3448 __update_field_vars(elt, rbe, rec, hist_data->save_vars, 3449 hist_data->n_save_vars, hist_data->n_field_var_str); 3450 } 3451 3452 static struct hist_field *create_var(struct hist_trigger_data *hist_data, 3453 struct trace_event_file *file, 3454 char *name, int size, const char *type) 3455 { 3456 struct hist_field *var; 3457 int idx; 3458 3459 if (find_var(hist_data, file, name) && !hist_data->remove) { 3460 var = ERR_PTR(-EINVAL); 3461 goto out; 3462 } 3463 3464 var = kzalloc(sizeof(struct hist_field), GFP_KERNEL); 3465 if (!var) { 3466 var = ERR_PTR(-ENOMEM); 3467 goto out; 3468 } 3469 3470 idx = tracing_map_add_var(hist_data->map); 3471 if (idx < 0) { 3472 kfree(var); 3473 var = ERR_PTR(-EINVAL); 3474 goto out; 3475 } 3476 3477 var->flags = HIST_FIELD_FL_VAR; 3478 var->var.idx = idx; 3479 var->var.hist_data = var->hist_data = hist_data; 3480 var->size = size; 3481 var->var.name = kstrdup(name, GFP_KERNEL); 3482 var->type = kstrdup(type, GFP_KERNEL); 3483 if (!var->var.name || !var->type) { 3484 kfree(var->var.name); 3485 kfree(var->type); 3486 kfree(var); 3487 var = ERR_PTR(-ENOMEM); 3488 } 3489 out: 3490 return var; 3491 } 3492 3493 static struct field_var *create_field_var(struct hist_trigger_data *hist_data, 3494 struct trace_event_file *file, 3495 char *field_name) 3496 { 3497 struct hist_field *val = NULL, *var = NULL; 3498 unsigned long flags = HIST_FIELD_FL_VAR; 3499 struct trace_array *tr = file->tr; 3500 struct field_var *field_var; 3501 int ret = 0; 3502 3503 if (hist_data->n_field_vars >= SYNTH_FIELDS_MAX) { 3504 hist_err(tr, HIST_ERR_TOO_MANY_FIELD_VARS, errpos(field_name)); 3505 ret = -EINVAL; 3506 goto err; 3507 } 3508 3509 val = parse_atom(hist_data, file, field_name, &flags, NULL); 3510 if (IS_ERR(val)) { 3511 hist_err(tr, HIST_ERR_FIELD_VAR_PARSE_FAIL, errpos(field_name)); 3512 ret = PTR_ERR(val); 3513 goto err; 3514 } 3515 3516 var = create_var(hist_data, file, field_name, val->size, val->type); 3517 if (IS_ERR(var)) { 3518 hist_err(tr, HIST_ERR_VAR_CREATE_FIND_FAIL, errpos(field_name)); 3519 kfree(val); 3520 ret = PTR_ERR(var); 3521 goto err; 3522 } 3523 3524 field_var = kzalloc(sizeof(struct field_var), GFP_KERNEL); 3525 if (!field_var) { 3526 kfree(val); 3527 kfree(var); 3528 ret = -ENOMEM; 3529 goto err; 3530 } 3531 3532 field_var->var = var; 3533 field_var->val = val; 3534 out: 3535 return field_var; 3536 err: 3537 field_var = ERR_PTR(ret); 3538 goto out; 3539 } 3540 3541 /** 3542 * create_target_field_var - Automatically create a variable for a field 3543 * @target_hist_data: The target hist trigger 3544 * @subsys_name: Optional subsystem name 3545 * @event_name: Optional event name 3546 * @var_name: The name of the field (and the resulting variable) 3547 * 3548 * Hist trigger actions fetch data from variables, not directly from 3549 * events. However, for convenience, users are allowed to directly 3550 * specify an event field in an action, which will be automatically 3551 * converted into a variable on their behalf. 3552 3553 * This function creates a field variable with the name var_name on 3554 * the hist trigger currently being defined on the target event. If 3555 * subsys_name and event_name are specified, this function simply 3556 * verifies that they do in fact match the target event subsystem and 3557 * event name. 3558 * 3559 * Return: The variable created for the field. 3560 */ 3561 static struct field_var * 3562 create_target_field_var(struct hist_trigger_data *target_hist_data, 3563 char *subsys_name, char *event_name, char *var_name) 3564 { 3565 struct trace_event_file *file = target_hist_data->event_file; 3566 3567 if (subsys_name) { 3568 struct trace_event_call *call; 3569 3570 if (!event_name) 3571 return NULL; 3572 3573 call = file->event_call; 3574 3575 if (strcmp(subsys_name, call->class->system) != 0) 3576 return NULL; 3577 3578 if (strcmp(event_name, trace_event_name(call)) != 0) 3579 return NULL; 3580 } 3581 3582 return create_field_var(target_hist_data, file, var_name); 3583 } 3584 3585 static bool check_track_val_max(u64 track_val, u64 var_val) 3586 { 3587 if (var_val <= track_val) 3588 return false; 3589 3590 return true; 3591 } 3592 3593 static bool check_track_val_changed(u64 track_val, u64 var_val) 3594 { 3595 if (var_val == track_val) 3596 return false; 3597 3598 return true; 3599 } 3600 3601 static u64 get_track_val(struct hist_trigger_data *hist_data, 3602 struct tracing_map_elt *elt, 3603 struct action_data *data) 3604 { 3605 unsigned int track_var_idx = data->track_data.track_var->var.idx; 3606 u64 track_val; 3607 3608 track_val = tracing_map_read_var(elt, track_var_idx); 3609 3610 return track_val; 3611 } 3612 3613 static void save_track_val(struct hist_trigger_data *hist_data, 3614 struct tracing_map_elt *elt, 3615 struct action_data *data, u64 var_val) 3616 { 3617 unsigned int track_var_idx = data->track_data.track_var->var.idx; 3618 3619 tracing_map_set_var(elt, track_var_idx, var_val); 3620 } 3621 3622 static void save_track_data(struct hist_trigger_data *hist_data, 3623 struct tracing_map_elt *elt, void *rec, 3624 struct ring_buffer_event *rbe, void *key, 3625 struct action_data *data, u64 *var_ref_vals) 3626 { 3627 if (data->track_data.save_data) 3628 data->track_data.save_data(hist_data, elt, rec, rbe, key, data, var_ref_vals); 3629 } 3630 3631 static bool check_track_val(struct tracing_map_elt *elt, 3632 struct action_data *data, 3633 u64 var_val) 3634 { 3635 struct hist_trigger_data *hist_data; 3636 u64 track_val; 3637 3638 hist_data = data->track_data.track_var->hist_data; 3639 track_val = get_track_val(hist_data, elt, data); 3640 3641 return data->track_data.check_val(track_val, var_val); 3642 } 3643 3644 #ifdef CONFIG_TRACER_SNAPSHOT 3645 static bool cond_snapshot_update(struct trace_array *tr, void *cond_data) 3646 { 3647 /* called with tr->max_lock held */ 3648 struct track_data *track_data = tr->cond_snapshot->cond_data; 3649 struct hist_elt_data *elt_data, *track_elt_data; 3650 struct snapshot_context *context = cond_data; 3651 struct action_data *action; 3652 u64 track_val; 3653 3654 if (!track_data) 3655 return false; 3656 3657 action = track_data->action_data; 3658 3659 track_val = get_track_val(track_data->hist_data, context->elt, 3660 track_data->action_data); 3661 3662 if (!action->track_data.check_val(track_data->track_val, track_val)) 3663 return false; 3664 3665 track_data->track_val = track_val; 3666 memcpy(track_data->key, context->key, track_data->key_len); 3667 3668 elt_data = context->elt->private_data; 3669 track_elt_data = track_data->elt.private_data; 3670 if (elt_data->comm) 3671 strncpy(track_elt_data->comm, elt_data->comm, TASK_COMM_LEN); 3672 3673 track_data->updated = true; 3674 3675 return true; 3676 } 3677 3678 static void save_track_data_snapshot(struct hist_trigger_data *hist_data, 3679 struct tracing_map_elt *elt, void *rec, 3680 struct ring_buffer_event *rbe, void *key, 3681 struct action_data *data, 3682 u64 *var_ref_vals) 3683 { 3684 struct trace_event_file *file = hist_data->event_file; 3685 struct snapshot_context context; 3686 3687 context.elt = elt; 3688 context.key = key; 3689 3690 tracing_snapshot_cond(file->tr, &context); 3691 } 3692 3693 static void hist_trigger_print_key(struct seq_file *m, 3694 struct hist_trigger_data *hist_data, 3695 void *key, 3696 struct tracing_map_elt *elt); 3697 3698 static struct action_data *snapshot_action(struct hist_trigger_data *hist_data) 3699 { 3700 unsigned int i; 3701 3702 if (!hist_data->n_actions) 3703 return NULL; 3704 3705 for (i = 0; i < hist_data->n_actions; i++) { 3706 struct action_data *data = hist_data->actions[i]; 3707 3708 if (data->action == ACTION_SNAPSHOT) 3709 return data; 3710 } 3711 3712 return NULL; 3713 } 3714 3715 static void track_data_snapshot_print(struct seq_file *m, 3716 struct hist_trigger_data *hist_data) 3717 { 3718 struct trace_event_file *file = hist_data->event_file; 3719 struct track_data *track_data; 3720 struct action_data *action; 3721 3722 track_data = tracing_cond_snapshot_data(file->tr); 3723 if (!track_data) 3724 return; 3725 3726 if (!track_data->updated) 3727 return; 3728 3729 action = snapshot_action(hist_data); 3730 if (!action) 3731 return; 3732 3733 seq_puts(m, "\nSnapshot taken (see tracing/snapshot). Details:\n"); 3734 seq_printf(m, "\ttriggering value { %s(%s) }: %10llu", 3735 action->handler == HANDLER_ONMAX ? "onmax" : "onchange", 3736 action->track_data.var_str, track_data->track_val); 3737 3738 seq_puts(m, "\ttriggered by event with key: "); 3739 hist_trigger_print_key(m, hist_data, track_data->key, &track_data->elt); 3740 seq_putc(m, '\n'); 3741 } 3742 #else 3743 static bool cond_snapshot_update(struct trace_array *tr, void *cond_data) 3744 { 3745 return false; 3746 } 3747 static void save_track_data_snapshot(struct hist_trigger_data *hist_data, 3748 struct tracing_map_elt *elt, void *rec, 3749 struct ring_buffer_event *rbe, void *key, 3750 struct action_data *data, 3751 u64 *var_ref_vals) {} 3752 static void track_data_snapshot_print(struct seq_file *m, 3753 struct hist_trigger_data *hist_data) {} 3754 #endif /* CONFIG_TRACER_SNAPSHOT */ 3755 3756 static void track_data_print(struct seq_file *m, 3757 struct hist_trigger_data *hist_data, 3758 struct tracing_map_elt *elt, 3759 struct action_data *data) 3760 { 3761 u64 track_val = get_track_val(hist_data, elt, data); 3762 unsigned int i, save_var_idx; 3763 3764 if (data->handler == HANDLER_ONMAX) 3765 seq_printf(m, "\n\tmax: %10llu", track_val); 3766 else if (data->handler == HANDLER_ONCHANGE) 3767 seq_printf(m, "\n\tchanged: %10llu", track_val); 3768 3769 if (data->action == ACTION_SNAPSHOT) 3770 return; 3771 3772 for (i = 0; i < hist_data->n_save_vars; i++) { 3773 struct hist_field *save_val = hist_data->save_vars[i]->val; 3774 struct hist_field *save_var = hist_data->save_vars[i]->var; 3775 u64 val; 3776 3777 save_var_idx = save_var->var.idx; 3778 3779 val = tracing_map_read_var(elt, save_var_idx); 3780 3781 if (save_val->flags & HIST_FIELD_FL_STRING) { 3782 seq_printf(m, " %s: %-32s", save_var->var.name, 3783 (char *)(uintptr_t)(val)); 3784 } else 3785 seq_printf(m, " %s: %10llu", save_var->var.name, val); 3786 } 3787 } 3788 3789 static void ontrack_action(struct hist_trigger_data *hist_data, 3790 struct tracing_map_elt *elt, void *rec, 3791 struct ring_buffer_event *rbe, void *key, 3792 struct action_data *data, u64 *var_ref_vals) 3793 { 3794 u64 var_val = var_ref_vals[data->track_data.var_ref->var_ref_idx]; 3795 3796 if (check_track_val(elt, data, var_val)) { 3797 save_track_val(hist_data, elt, data, var_val); 3798 save_track_data(hist_data, elt, rec, rbe, key, data, var_ref_vals); 3799 } 3800 } 3801 3802 static void action_data_destroy(struct action_data *data) 3803 { 3804 unsigned int i; 3805 3806 lockdep_assert_held(&event_mutex); 3807 3808 kfree(data->action_name); 3809 3810 for (i = 0; i < data->n_params; i++) 3811 kfree(data->params[i]); 3812 3813 if (data->synth_event) 3814 data->synth_event->ref--; 3815 3816 kfree(data->synth_event_name); 3817 3818 kfree(data); 3819 } 3820 3821 static void track_data_destroy(struct hist_trigger_data *hist_data, 3822 struct action_data *data) 3823 { 3824 struct trace_event_file *file = hist_data->event_file; 3825 3826 destroy_hist_field(data->track_data.track_var, 0); 3827 3828 if (data->action == ACTION_SNAPSHOT) { 3829 struct track_data *track_data; 3830 3831 track_data = tracing_cond_snapshot_data(file->tr); 3832 if (track_data && track_data->hist_data == hist_data) { 3833 tracing_snapshot_cond_disable(file->tr); 3834 track_data_free(track_data); 3835 } 3836 } 3837 3838 kfree(data->track_data.var_str); 3839 3840 action_data_destroy(data); 3841 } 3842 3843 static int action_create(struct hist_trigger_data *hist_data, 3844 struct action_data *data); 3845 3846 static int track_data_create(struct hist_trigger_data *hist_data, 3847 struct action_data *data) 3848 { 3849 struct hist_field *var_field, *ref_field, *track_var = NULL; 3850 struct trace_event_file *file = hist_data->event_file; 3851 struct trace_array *tr = file->tr; 3852 char *track_data_var_str; 3853 int ret = 0; 3854 3855 track_data_var_str = data->track_data.var_str; 3856 if (track_data_var_str[0] != '$') { 3857 hist_err(tr, HIST_ERR_ONX_NOT_VAR, errpos(track_data_var_str)); 3858 return -EINVAL; 3859 } 3860 track_data_var_str++; 3861 3862 var_field = find_target_event_var(hist_data, NULL, NULL, track_data_var_str); 3863 if (!var_field) { 3864 hist_err(tr, HIST_ERR_ONX_VAR_NOT_FOUND, errpos(track_data_var_str)); 3865 return -EINVAL; 3866 } 3867 3868 ref_field = create_var_ref(hist_data, var_field, NULL, NULL); 3869 if (!ref_field) 3870 return -ENOMEM; 3871 3872 data->track_data.var_ref = ref_field; 3873 3874 if (data->handler == HANDLER_ONMAX) 3875 track_var = create_var(hist_data, file, "__max", sizeof(u64), "u64"); 3876 if (IS_ERR(track_var)) { 3877 hist_err(tr, HIST_ERR_ONX_VAR_CREATE_FAIL, 0); 3878 ret = PTR_ERR(track_var); 3879 goto out; 3880 } 3881 3882 if (data->handler == HANDLER_ONCHANGE) 3883 track_var = create_var(hist_data, file, "__change", sizeof(u64), "u64"); 3884 if (IS_ERR(track_var)) { 3885 hist_err(tr, HIST_ERR_ONX_VAR_CREATE_FAIL, 0); 3886 ret = PTR_ERR(track_var); 3887 goto out; 3888 } 3889 data->track_data.track_var = track_var; 3890 3891 ret = action_create(hist_data, data); 3892 out: 3893 return ret; 3894 } 3895 3896 static int parse_action_params(struct trace_array *tr, char *params, 3897 struct action_data *data) 3898 { 3899 char *param, *saved_param; 3900 bool first_param = true; 3901 int ret = 0; 3902 3903 while (params) { 3904 if (data->n_params >= SYNTH_FIELDS_MAX) { 3905 hist_err(tr, HIST_ERR_TOO_MANY_PARAMS, 0); 3906 goto out; 3907 } 3908 3909 param = strsep(¶ms, ","); 3910 if (!param) { 3911 hist_err(tr, HIST_ERR_PARAM_NOT_FOUND, 0); 3912 ret = -EINVAL; 3913 goto out; 3914 } 3915 3916 param = strstrip(param); 3917 if (strlen(param) < 2) { 3918 hist_err(tr, HIST_ERR_INVALID_PARAM, errpos(param)); 3919 ret = -EINVAL; 3920 goto out; 3921 } 3922 3923 saved_param = kstrdup(param, GFP_KERNEL); 3924 if (!saved_param) { 3925 ret = -ENOMEM; 3926 goto out; 3927 } 3928 3929 if (first_param && data->use_trace_keyword) { 3930 data->synth_event_name = saved_param; 3931 first_param = false; 3932 continue; 3933 } 3934 first_param = false; 3935 3936 data->params[data->n_params++] = saved_param; 3937 } 3938 out: 3939 return ret; 3940 } 3941 3942 static int action_parse(struct trace_array *tr, char *str, struct action_data *data, 3943 enum handler_id handler) 3944 { 3945 char *action_name; 3946 int ret = 0; 3947 3948 strsep(&str, "."); 3949 if (!str) { 3950 hist_err(tr, HIST_ERR_ACTION_NOT_FOUND, 0); 3951 ret = -EINVAL; 3952 goto out; 3953 } 3954 3955 action_name = strsep(&str, "("); 3956 if (!action_name || !str) { 3957 hist_err(tr, HIST_ERR_ACTION_NOT_FOUND, 0); 3958 ret = -EINVAL; 3959 goto out; 3960 } 3961 3962 if (str_has_prefix(action_name, "save")) { 3963 char *params = strsep(&str, ")"); 3964 3965 if (!params) { 3966 hist_err(tr, HIST_ERR_NO_SAVE_PARAMS, 0); 3967 ret = -EINVAL; 3968 goto out; 3969 } 3970 3971 ret = parse_action_params(tr, params, data); 3972 if (ret) 3973 goto out; 3974 3975 if (handler == HANDLER_ONMAX) 3976 data->track_data.check_val = check_track_val_max; 3977 else if (handler == HANDLER_ONCHANGE) 3978 data->track_data.check_val = check_track_val_changed; 3979 else { 3980 hist_err(tr, HIST_ERR_ACTION_MISMATCH, errpos(action_name)); 3981 ret = -EINVAL; 3982 goto out; 3983 } 3984 3985 data->track_data.save_data = save_track_data_vars; 3986 data->fn = ontrack_action; 3987 data->action = ACTION_SAVE; 3988 } else if (str_has_prefix(action_name, "snapshot")) { 3989 char *params = strsep(&str, ")"); 3990 3991 if (!str) { 3992 hist_err(tr, HIST_ERR_NO_CLOSING_PAREN, errpos(params)); 3993 ret = -EINVAL; 3994 goto out; 3995 } 3996 3997 if (handler == HANDLER_ONMAX) 3998 data->track_data.check_val = check_track_val_max; 3999 else if (handler == HANDLER_ONCHANGE) 4000 data->track_data.check_val = check_track_val_changed; 4001 else { 4002 hist_err(tr, HIST_ERR_ACTION_MISMATCH, errpos(action_name)); 4003 ret = -EINVAL; 4004 goto out; 4005 } 4006 4007 data->track_data.save_data = save_track_data_snapshot; 4008 data->fn = ontrack_action; 4009 data->action = ACTION_SNAPSHOT; 4010 } else { 4011 char *params = strsep(&str, ")"); 4012 4013 if (str_has_prefix(action_name, "trace")) 4014 data->use_trace_keyword = true; 4015 4016 if (params) { 4017 ret = parse_action_params(tr, params, data); 4018 if (ret) 4019 goto out; 4020 } 4021 4022 if (handler == HANDLER_ONMAX) 4023 data->track_data.check_val = check_track_val_max; 4024 else if (handler == HANDLER_ONCHANGE) 4025 data->track_data.check_val = check_track_val_changed; 4026 4027 if (handler != HANDLER_ONMATCH) { 4028 data->track_data.save_data = action_trace; 4029 data->fn = ontrack_action; 4030 } else 4031 data->fn = action_trace; 4032 4033 data->action = ACTION_TRACE; 4034 } 4035 4036 data->action_name = kstrdup(action_name, GFP_KERNEL); 4037 if (!data->action_name) { 4038 ret = -ENOMEM; 4039 goto out; 4040 } 4041 4042 data->handler = handler; 4043 out: 4044 return ret; 4045 } 4046 4047 static struct action_data *track_data_parse(struct hist_trigger_data *hist_data, 4048 char *str, enum handler_id handler) 4049 { 4050 struct action_data *data; 4051 int ret = -EINVAL; 4052 char *var_str; 4053 4054 data = kzalloc(sizeof(*data), GFP_KERNEL); 4055 if (!data) 4056 return ERR_PTR(-ENOMEM); 4057 4058 var_str = strsep(&str, ")"); 4059 if (!var_str || !str) { 4060 ret = -EINVAL; 4061 goto free; 4062 } 4063 4064 data->track_data.var_str = kstrdup(var_str, GFP_KERNEL); 4065 if (!data->track_data.var_str) { 4066 ret = -ENOMEM; 4067 goto free; 4068 } 4069 4070 ret = action_parse(hist_data->event_file->tr, str, data, handler); 4071 if (ret) 4072 goto free; 4073 out: 4074 return data; 4075 free: 4076 track_data_destroy(hist_data, data); 4077 data = ERR_PTR(ret); 4078 goto out; 4079 } 4080 4081 static void onmatch_destroy(struct action_data *data) 4082 { 4083 kfree(data->match_data.event); 4084 kfree(data->match_data.event_system); 4085 4086 action_data_destroy(data); 4087 } 4088 4089 static void destroy_field_var(struct field_var *field_var) 4090 { 4091 if (!field_var) 4092 return; 4093 4094 destroy_hist_field(field_var->var, 0); 4095 destroy_hist_field(field_var->val, 0); 4096 4097 kfree(field_var); 4098 } 4099 4100 static void destroy_field_vars(struct hist_trigger_data *hist_data) 4101 { 4102 unsigned int i; 4103 4104 for (i = 0; i < hist_data->n_field_vars; i++) 4105 destroy_field_var(hist_data->field_vars[i]); 4106 } 4107 4108 static void save_field_var(struct hist_trigger_data *hist_data, 4109 struct field_var *field_var) 4110 { 4111 hist_data->field_vars[hist_data->n_field_vars++] = field_var; 4112 4113 if (field_var->val->flags & HIST_FIELD_FL_STRING) 4114 hist_data->n_field_var_str++; 4115 } 4116 4117 4118 static int check_synth_field(struct synth_event *event, 4119 struct hist_field *hist_field, 4120 unsigned int field_pos) 4121 { 4122 struct synth_field *field; 4123 4124 if (field_pos >= event->n_fields) 4125 return -EINVAL; 4126 4127 field = event->fields[field_pos]; 4128 4129 if (strcmp(field->type, hist_field->type) != 0) { 4130 if (field->size != hist_field->size || 4131 field->is_signed != hist_field->is_signed) 4132 return -EINVAL; 4133 } 4134 4135 return 0; 4136 } 4137 4138 static struct hist_field * 4139 trace_action_find_var(struct hist_trigger_data *hist_data, 4140 struct action_data *data, 4141 char *system, char *event, char *var) 4142 { 4143 struct trace_array *tr = hist_data->event_file->tr; 4144 struct hist_field *hist_field; 4145 4146 var++; /* skip '$' */ 4147 4148 hist_field = find_target_event_var(hist_data, system, event, var); 4149 if (!hist_field) { 4150 if (!system && data->handler == HANDLER_ONMATCH) { 4151 system = data->match_data.event_system; 4152 event = data->match_data.event; 4153 } 4154 4155 hist_field = find_event_var(hist_data, system, event, var); 4156 } 4157 4158 if (!hist_field) 4159 hist_err(tr, HIST_ERR_PARAM_NOT_FOUND, errpos(var)); 4160 4161 return hist_field; 4162 } 4163 4164 static struct hist_field * 4165 trace_action_create_field_var(struct hist_trigger_data *hist_data, 4166 struct action_data *data, char *system, 4167 char *event, char *var) 4168 { 4169 struct hist_field *hist_field = NULL; 4170 struct field_var *field_var; 4171 4172 /* 4173 * First try to create a field var on the target event (the 4174 * currently being defined). This will create a variable for 4175 * unqualified fields on the target event, or if qualified, 4176 * target fields that have qualified names matching the target. 4177 */ 4178 field_var = create_target_field_var(hist_data, system, event, var); 4179 4180 if (field_var && !IS_ERR(field_var)) { 4181 save_field_var(hist_data, field_var); 4182 hist_field = field_var->var; 4183 } else { 4184 field_var = NULL; 4185 /* 4186 * If no explicit system.event is specfied, default to 4187 * looking for fields on the onmatch(system.event.xxx) 4188 * event. 4189 */ 4190 if (!system && data->handler == HANDLER_ONMATCH) { 4191 system = data->match_data.event_system; 4192 event = data->match_data.event; 4193 } 4194 4195 /* 4196 * At this point, we're looking at a field on another 4197 * event. Because we can't modify a hist trigger on 4198 * another event to add a variable for a field, we need 4199 * to create a new trigger on that event and create the 4200 * variable at the same time. 4201 */ 4202 hist_field = create_field_var_hist(hist_data, system, event, var); 4203 if (IS_ERR(hist_field)) 4204 goto free; 4205 } 4206 out: 4207 return hist_field; 4208 free: 4209 destroy_field_var(field_var); 4210 hist_field = NULL; 4211 goto out; 4212 } 4213 4214 static int trace_action_create(struct hist_trigger_data *hist_data, 4215 struct action_data *data) 4216 { 4217 struct trace_array *tr = hist_data->event_file->tr; 4218 char *event_name, *param, *system = NULL; 4219 struct hist_field *hist_field, *var_ref; 4220 unsigned int i, var_ref_idx; 4221 unsigned int field_pos = 0; 4222 struct synth_event *event; 4223 char *synth_event_name; 4224 int ret = 0; 4225 4226 lockdep_assert_held(&event_mutex); 4227 4228 if (data->use_trace_keyword) 4229 synth_event_name = data->synth_event_name; 4230 else 4231 synth_event_name = data->action_name; 4232 4233 event = find_synth_event(synth_event_name); 4234 if (!event) { 4235 hist_err(tr, HIST_ERR_SYNTH_EVENT_NOT_FOUND, errpos(synth_event_name)); 4236 return -EINVAL; 4237 } 4238 4239 event->ref++; 4240 4241 var_ref_idx = hist_data->n_var_refs; 4242 4243 for (i = 0; i < data->n_params; i++) { 4244 char *p; 4245 4246 p = param = kstrdup(data->params[i], GFP_KERNEL); 4247 if (!param) { 4248 ret = -ENOMEM; 4249 goto err; 4250 } 4251 4252 system = strsep(¶m, "."); 4253 if (!param) { 4254 param = (char *)system; 4255 system = event_name = NULL; 4256 } else { 4257 event_name = strsep(¶m, "."); 4258 if (!param) { 4259 kfree(p); 4260 ret = -EINVAL; 4261 goto err; 4262 } 4263 } 4264 4265 if (param[0] == '$') 4266 hist_field = trace_action_find_var(hist_data, data, 4267 system, event_name, 4268 param); 4269 else 4270 hist_field = trace_action_create_field_var(hist_data, 4271 data, 4272 system, 4273 event_name, 4274 param); 4275 4276 if (!hist_field) { 4277 kfree(p); 4278 ret = -EINVAL; 4279 goto err; 4280 } 4281 4282 if (check_synth_field(event, hist_field, field_pos) == 0) { 4283 var_ref = create_var_ref(hist_data, hist_field, 4284 system, event_name); 4285 if (!var_ref) { 4286 kfree(p); 4287 ret = -ENOMEM; 4288 goto err; 4289 } 4290 4291 field_pos++; 4292 kfree(p); 4293 continue; 4294 } 4295 4296 hist_err(tr, HIST_ERR_SYNTH_TYPE_MISMATCH, errpos(param)); 4297 kfree(p); 4298 ret = -EINVAL; 4299 goto err; 4300 } 4301 4302 if (field_pos != event->n_fields) { 4303 hist_err(tr, HIST_ERR_SYNTH_COUNT_MISMATCH, errpos(event->name)); 4304 ret = -EINVAL; 4305 goto err; 4306 } 4307 4308 data->synth_event = event; 4309 data->var_ref_idx = var_ref_idx; 4310 out: 4311 return ret; 4312 err: 4313 event->ref--; 4314 4315 goto out; 4316 } 4317 4318 static int action_create(struct hist_trigger_data *hist_data, 4319 struct action_data *data) 4320 { 4321 struct trace_event_file *file = hist_data->event_file; 4322 struct trace_array *tr = file->tr; 4323 struct track_data *track_data; 4324 struct field_var *field_var; 4325 unsigned int i; 4326 char *param; 4327 int ret = 0; 4328 4329 if (data->action == ACTION_TRACE) 4330 return trace_action_create(hist_data, data); 4331 4332 if (data->action == ACTION_SNAPSHOT) { 4333 track_data = track_data_alloc(hist_data->key_size, data, hist_data); 4334 if (IS_ERR(track_data)) { 4335 ret = PTR_ERR(track_data); 4336 goto out; 4337 } 4338 4339 ret = tracing_snapshot_cond_enable(file->tr, track_data, 4340 cond_snapshot_update); 4341 if (ret) 4342 track_data_free(track_data); 4343 4344 goto out; 4345 } 4346 4347 if (data->action == ACTION_SAVE) { 4348 if (hist_data->n_save_vars) { 4349 ret = -EEXIST; 4350 hist_err(tr, HIST_ERR_TOO_MANY_SAVE_ACTIONS, 0); 4351 goto out; 4352 } 4353 4354 for (i = 0; i < data->n_params; i++) { 4355 param = kstrdup(data->params[i], GFP_KERNEL); 4356 if (!param) { 4357 ret = -ENOMEM; 4358 goto out; 4359 } 4360 4361 field_var = create_target_field_var(hist_data, NULL, NULL, param); 4362 if (IS_ERR(field_var)) { 4363 hist_err(tr, HIST_ERR_FIELD_VAR_CREATE_FAIL, 4364 errpos(param)); 4365 ret = PTR_ERR(field_var); 4366 kfree(param); 4367 goto out; 4368 } 4369 4370 hist_data->save_vars[hist_data->n_save_vars++] = field_var; 4371 if (field_var->val->flags & HIST_FIELD_FL_STRING) 4372 hist_data->n_save_var_str++; 4373 kfree(param); 4374 } 4375 } 4376 out: 4377 return ret; 4378 } 4379 4380 static int onmatch_create(struct hist_trigger_data *hist_data, 4381 struct action_data *data) 4382 { 4383 return action_create(hist_data, data); 4384 } 4385 4386 static struct action_data *onmatch_parse(struct trace_array *tr, char *str) 4387 { 4388 char *match_event, *match_event_system; 4389 struct action_data *data; 4390 int ret = -EINVAL; 4391 4392 data = kzalloc(sizeof(*data), GFP_KERNEL); 4393 if (!data) 4394 return ERR_PTR(-ENOMEM); 4395 4396 match_event = strsep(&str, ")"); 4397 if (!match_event || !str) { 4398 hist_err(tr, HIST_ERR_NO_CLOSING_PAREN, errpos(match_event)); 4399 goto free; 4400 } 4401 4402 match_event_system = strsep(&match_event, "."); 4403 if (!match_event) { 4404 hist_err(tr, HIST_ERR_SUBSYS_NOT_FOUND, errpos(match_event_system)); 4405 goto free; 4406 } 4407 4408 if (IS_ERR(event_file(tr, match_event_system, match_event))) { 4409 hist_err(tr, HIST_ERR_INVALID_SUBSYS_EVENT, errpos(match_event)); 4410 goto free; 4411 } 4412 4413 data->match_data.event = kstrdup(match_event, GFP_KERNEL); 4414 if (!data->match_data.event) { 4415 ret = -ENOMEM; 4416 goto free; 4417 } 4418 4419 data->match_data.event_system = kstrdup(match_event_system, GFP_KERNEL); 4420 if (!data->match_data.event_system) { 4421 ret = -ENOMEM; 4422 goto free; 4423 } 4424 4425 ret = action_parse(tr, str, data, HANDLER_ONMATCH); 4426 if (ret) 4427 goto free; 4428 out: 4429 return data; 4430 free: 4431 onmatch_destroy(data); 4432 data = ERR_PTR(ret); 4433 goto out; 4434 } 4435 4436 static int create_hitcount_val(struct hist_trigger_data *hist_data) 4437 { 4438 hist_data->fields[HITCOUNT_IDX] = 4439 create_hist_field(hist_data, NULL, HIST_FIELD_FL_HITCOUNT, NULL); 4440 if (!hist_data->fields[HITCOUNT_IDX]) 4441 return -ENOMEM; 4442 4443 hist_data->n_vals++; 4444 hist_data->n_fields++; 4445 4446 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX)) 4447 return -EINVAL; 4448 4449 return 0; 4450 } 4451 4452 static int __create_val_field(struct hist_trigger_data *hist_data, 4453 unsigned int val_idx, 4454 struct trace_event_file *file, 4455 char *var_name, char *field_str, 4456 unsigned long flags) 4457 { 4458 struct hist_field *hist_field; 4459 int ret = 0; 4460 4461 hist_field = parse_expr(hist_data, file, field_str, flags, var_name, 0); 4462 if (IS_ERR(hist_field)) { 4463 ret = PTR_ERR(hist_field); 4464 goto out; 4465 } 4466 4467 hist_data->fields[val_idx] = hist_field; 4468 4469 ++hist_data->n_vals; 4470 ++hist_data->n_fields; 4471 4472 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX)) 4473 ret = -EINVAL; 4474 out: 4475 return ret; 4476 } 4477 4478 static int create_val_field(struct hist_trigger_data *hist_data, 4479 unsigned int val_idx, 4480 struct trace_event_file *file, 4481 char *field_str) 4482 { 4483 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX)) 4484 return -EINVAL; 4485 4486 return __create_val_field(hist_data, val_idx, file, NULL, field_str, 0); 4487 } 4488 4489 static int create_var_field(struct hist_trigger_data *hist_data, 4490 unsigned int val_idx, 4491 struct trace_event_file *file, 4492 char *var_name, char *expr_str) 4493 { 4494 struct trace_array *tr = hist_data->event_file->tr; 4495 unsigned long flags = 0; 4496 4497 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX)) 4498 return -EINVAL; 4499 4500 if (find_var(hist_data, file, var_name) && !hist_data->remove) { 4501 hist_err(tr, HIST_ERR_DUPLICATE_VAR, errpos(var_name)); 4502 return -EINVAL; 4503 } 4504 4505 flags |= HIST_FIELD_FL_VAR; 4506 hist_data->n_vars++; 4507 if (WARN_ON(hist_data->n_vars > TRACING_MAP_VARS_MAX)) 4508 return -EINVAL; 4509 4510 return __create_val_field(hist_data, val_idx, file, var_name, expr_str, flags); 4511 } 4512 4513 static int create_val_fields(struct hist_trigger_data *hist_data, 4514 struct trace_event_file *file) 4515 { 4516 char *fields_str, *field_str; 4517 unsigned int i, j = 1; 4518 int ret; 4519 4520 ret = create_hitcount_val(hist_data); 4521 if (ret) 4522 goto out; 4523 4524 fields_str = hist_data->attrs->vals_str; 4525 if (!fields_str) 4526 goto out; 4527 4528 for (i = 0, j = 1; i < TRACING_MAP_VALS_MAX && 4529 j < TRACING_MAP_VALS_MAX; i++) { 4530 field_str = strsep(&fields_str, ","); 4531 if (!field_str) 4532 break; 4533 4534 if (strcmp(field_str, "hitcount") == 0) 4535 continue; 4536 4537 ret = create_val_field(hist_data, j++, file, field_str); 4538 if (ret) 4539 goto out; 4540 } 4541 4542 if (fields_str && (strcmp(fields_str, "hitcount") != 0)) 4543 ret = -EINVAL; 4544 out: 4545 return ret; 4546 } 4547 4548 static int create_key_field(struct hist_trigger_data *hist_data, 4549 unsigned int key_idx, 4550 unsigned int key_offset, 4551 struct trace_event_file *file, 4552 char *field_str) 4553 { 4554 struct trace_array *tr = hist_data->event_file->tr; 4555 struct hist_field *hist_field = NULL; 4556 unsigned long flags = 0; 4557 unsigned int key_size; 4558 int ret = 0; 4559 4560 if (WARN_ON(key_idx >= HIST_FIELDS_MAX)) 4561 return -EINVAL; 4562 4563 flags |= HIST_FIELD_FL_KEY; 4564 4565 if (strcmp(field_str, "stacktrace") == 0) { 4566 flags |= HIST_FIELD_FL_STACKTRACE; 4567 key_size = sizeof(unsigned long) * HIST_STACKTRACE_DEPTH; 4568 hist_field = create_hist_field(hist_data, NULL, flags, NULL); 4569 } else { 4570 hist_field = parse_expr(hist_data, file, field_str, flags, 4571 NULL, 0); 4572 if (IS_ERR(hist_field)) { 4573 ret = PTR_ERR(hist_field); 4574 goto out; 4575 } 4576 4577 if (field_has_hist_vars(hist_field, 0)) { 4578 hist_err(tr, HIST_ERR_INVALID_REF_KEY, errpos(field_str)); 4579 destroy_hist_field(hist_field, 0); 4580 ret = -EINVAL; 4581 goto out; 4582 } 4583 4584 key_size = hist_field->size; 4585 } 4586 4587 hist_data->fields[key_idx] = hist_field; 4588 4589 key_size = ALIGN(key_size, sizeof(u64)); 4590 hist_data->fields[key_idx]->size = key_size; 4591 hist_data->fields[key_idx]->offset = key_offset; 4592 4593 hist_data->key_size += key_size; 4594 4595 if (hist_data->key_size > HIST_KEY_SIZE_MAX) { 4596 ret = -EINVAL; 4597 goto out; 4598 } 4599 4600 hist_data->n_keys++; 4601 hist_data->n_fields++; 4602 4603 if (WARN_ON(hist_data->n_keys > TRACING_MAP_KEYS_MAX)) 4604 return -EINVAL; 4605 4606 ret = key_size; 4607 out: 4608 return ret; 4609 } 4610 4611 static int create_key_fields(struct hist_trigger_data *hist_data, 4612 struct trace_event_file *file) 4613 { 4614 unsigned int i, key_offset = 0, n_vals = hist_data->n_vals; 4615 char *fields_str, *field_str; 4616 int ret = -EINVAL; 4617 4618 fields_str = hist_data->attrs->keys_str; 4619 if (!fields_str) 4620 goto out; 4621 4622 for (i = n_vals; i < n_vals + TRACING_MAP_KEYS_MAX; i++) { 4623 field_str = strsep(&fields_str, ","); 4624 if (!field_str) 4625 break; 4626 ret = create_key_field(hist_data, i, key_offset, 4627 file, field_str); 4628 if (ret < 0) 4629 goto out; 4630 key_offset += ret; 4631 } 4632 if (fields_str) { 4633 ret = -EINVAL; 4634 goto out; 4635 } 4636 ret = 0; 4637 out: 4638 return ret; 4639 } 4640 4641 static int create_var_fields(struct hist_trigger_data *hist_data, 4642 struct trace_event_file *file) 4643 { 4644 unsigned int i, j = hist_data->n_vals; 4645 int ret = 0; 4646 4647 unsigned int n_vars = hist_data->attrs->var_defs.n_vars; 4648 4649 for (i = 0; i < n_vars; i++) { 4650 char *var_name = hist_data->attrs->var_defs.name[i]; 4651 char *expr = hist_data->attrs->var_defs.expr[i]; 4652 4653 ret = create_var_field(hist_data, j++, file, var_name, expr); 4654 if (ret) 4655 goto out; 4656 } 4657 out: 4658 return ret; 4659 } 4660 4661 static void free_var_defs(struct hist_trigger_data *hist_data) 4662 { 4663 unsigned int i; 4664 4665 for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) { 4666 kfree(hist_data->attrs->var_defs.name[i]); 4667 kfree(hist_data->attrs->var_defs.expr[i]); 4668 } 4669 4670 hist_data->attrs->var_defs.n_vars = 0; 4671 } 4672 4673 static int parse_var_defs(struct hist_trigger_data *hist_data) 4674 { 4675 struct trace_array *tr = hist_data->event_file->tr; 4676 char *s, *str, *var_name, *field_str; 4677 unsigned int i, j, n_vars = 0; 4678 int ret = 0; 4679 4680 for (i = 0; i < hist_data->attrs->n_assignments; i++) { 4681 str = hist_data->attrs->assignment_str[i]; 4682 for (j = 0; j < TRACING_MAP_VARS_MAX; j++) { 4683 field_str = strsep(&str, ","); 4684 if (!field_str) 4685 break; 4686 4687 var_name = strsep(&field_str, "="); 4688 if (!var_name || !field_str) { 4689 hist_err(tr, HIST_ERR_MALFORMED_ASSIGNMENT, 4690 errpos(var_name)); 4691 ret = -EINVAL; 4692 goto free; 4693 } 4694 4695 if (n_vars == TRACING_MAP_VARS_MAX) { 4696 hist_err(tr, HIST_ERR_TOO_MANY_VARS, errpos(var_name)); 4697 ret = -EINVAL; 4698 goto free; 4699 } 4700 4701 s = kstrdup(var_name, GFP_KERNEL); 4702 if (!s) { 4703 ret = -ENOMEM; 4704 goto free; 4705 } 4706 hist_data->attrs->var_defs.name[n_vars] = s; 4707 4708 s = kstrdup(field_str, GFP_KERNEL); 4709 if (!s) { 4710 kfree(hist_data->attrs->var_defs.name[n_vars]); 4711 ret = -ENOMEM; 4712 goto free; 4713 } 4714 hist_data->attrs->var_defs.expr[n_vars++] = s; 4715 4716 hist_data->attrs->var_defs.n_vars = n_vars; 4717 } 4718 } 4719 4720 return ret; 4721 free: 4722 free_var_defs(hist_data); 4723 4724 return ret; 4725 } 4726 4727 static int create_hist_fields(struct hist_trigger_data *hist_data, 4728 struct trace_event_file *file) 4729 { 4730 int ret; 4731 4732 ret = parse_var_defs(hist_data); 4733 if (ret) 4734 goto out; 4735 4736 ret = create_val_fields(hist_data, file); 4737 if (ret) 4738 goto out; 4739 4740 ret = create_var_fields(hist_data, file); 4741 if (ret) 4742 goto out; 4743 4744 ret = create_key_fields(hist_data, file); 4745 if (ret) 4746 goto out; 4747 out: 4748 free_var_defs(hist_data); 4749 4750 return ret; 4751 } 4752 4753 static int is_descending(struct trace_array *tr, const char *str) 4754 { 4755 if (!str) 4756 return 0; 4757 4758 if (strcmp(str, "descending") == 0) 4759 return 1; 4760 4761 if (strcmp(str, "ascending") == 0) 4762 return 0; 4763 4764 hist_err(tr, HIST_ERR_INVALID_SORT_MODIFIER, errpos((char *)str)); 4765 4766 return -EINVAL; 4767 } 4768 4769 static int create_sort_keys(struct hist_trigger_data *hist_data) 4770 { 4771 struct trace_array *tr = hist_data->event_file->tr; 4772 char *fields_str = hist_data->attrs->sort_key_str; 4773 struct tracing_map_sort_key *sort_key; 4774 int descending, ret = 0; 4775 unsigned int i, j, k; 4776 4777 hist_data->n_sort_keys = 1; /* we always have at least one, hitcount */ 4778 4779 if (!fields_str) 4780 goto out; 4781 4782 for (i = 0; i < TRACING_MAP_SORT_KEYS_MAX; i++) { 4783 struct hist_field *hist_field; 4784 char *field_str, *field_name; 4785 const char *test_name; 4786 4787 sort_key = &hist_data->sort_keys[i]; 4788 4789 field_str = strsep(&fields_str, ","); 4790 if (!field_str) 4791 break; 4792 4793 if (!*field_str) { 4794 ret = -EINVAL; 4795 hist_err(tr, HIST_ERR_EMPTY_SORT_FIELD, errpos("sort=")); 4796 break; 4797 } 4798 4799 if ((i == TRACING_MAP_SORT_KEYS_MAX - 1) && fields_str) { 4800 hist_err(tr, HIST_ERR_TOO_MANY_SORT_FIELDS, errpos("sort=")); 4801 ret = -EINVAL; 4802 break; 4803 } 4804 4805 field_name = strsep(&field_str, "."); 4806 if (!field_name || !*field_name) { 4807 ret = -EINVAL; 4808 hist_err(tr, HIST_ERR_EMPTY_SORT_FIELD, errpos("sort=")); 4809 break; 4810 } 4811 4812 if (strcmp(field_name, "hitcount") == 0) { 4813 descending = is_descending(tr, field_str); 4814 if (descending < 0) { 4815 ret = descending; 4816 break; 4817 } 4818 sort_key->descending = descending; 4819 continue; 4820 } 4821 4822 for (j = 1, k = 1; j < hist_data->n_fields; j++) { 4823 unsigned int idx; 4824 4825 hist_field = hist_data->fields[j]; 4826 if (hist_field->flags & HIST_FIELD_FL_VAR) 4827 continue; 4828 4829 idx = k++; 4830 4831 test_name = hist_field_name(hist_field, 0); 4832 4833 if (strcmp(field_name, test_name) == 0) { 4834 sort_key->field_idx = idx; 4835 descending = is_descending(tr, field_str); 4836 if (descending < 0) { 4837 ret = descending; 4838 goto out; 4839 } 4840 sort_key->descending = descending; 4841 break; 4842 } 4843 } 4844 if (j == hist_data->n_fields) { 4845 ret = -EINVAL; 4846 hist_err(tr, HIST_ERR_INVALID_SORT_FIELD, errpos(field_name)); 4847 break; 4848 } 4849 } 4850 4851 hist_data->n_sort_keys = i; 4852 out: 4853 return ret; 4854 } 4855 4856 static void destroy_actions(struct hist_trigger_data *hist_data) 4857 { 4858 unsigned int i; 4859 4860 for (i = 0; i < hist_data->n_actions; i++) { 4861 struct action_data *data = hist_data->actions[i]; 4862 4863 if (data->handler == HANDLER_ONMATCH) 4864 onmatch_destroy(data); 4865 else if (data->handler == HANDLER_ONMAX || 4866 data->handler == HANDLER_ONCHANGE) 4867 track_data_destroy(hist_data, data); 4868 else 4869 kfree(data); 4870 } 4871 } 4872 4873 static int parse_actions(struct hist_trigger_data *hist_data) 4874 { 4875 struct trace_array *tr = hist_data->event_file->tr; 4876 struct action_data *data; 4877 unsigned int i; 4878 int ret = 0; 4879 char *str; 4880 int len; 4881 4882 for (i = 0; i < hist_data->attrs->n_actions; i++) { 4883 str = hist_data->attrs->action_str[i]; 4884 4885 if ((len = str_has_prefix(str, "onmatch("))) { 4886 char *action_str = str + len; 4887 4888 data = onmatch_parse(tr, action_str); 4889 if (IS_ERR(data)) { 4890 ret = PTR_ERR(data); 4891 break; 4892 } 4893 } else if ((len = str_has_prefix(str, "onmax("))) { 4894 char *action_str = str + len; 4895 4896 data = track_data_parse(hist_data, action_str, 4897 HANDLER_ONMAX); 4898 if (IS_ERR(data)) { 4899 ret = PTR_ERR(data); 4900 break; 4901 } 4902 } else if ((len = str_has_prefix(str, "onchange("))) { 4903 char *action_str = str + len; 4904 4905 data = track_data_parse(hist_data, action_str, 4906 HANDLER_ONCHANGE); 4907 if (IS_ERR(data)) { 4908 ret = PTR_ERR(data); 4909 break; 4910 } 4911 } else { 4912 ret = -EINVAL; 4913 break; 4914 } 4915 4916 hist_data->actions[hist_data->n_actions++] = data; 4917 } 4918 4919 return ret; 4920 } 4921 4922 static int create_actions(struct hist_trigger_data *hist_data) 4923 { 4924 struct action_data *data; 4925 unsigned int i; 4926 int ret = 0; 4927 4928 for (i = 0; i < hist_data->attrs->n_actions; i++) { 4929 data = hist_data->actions[i]; 4930 4931 if (data->handler == HANDLER_ONMATCH) { 4932 ret = onmatch_create(hist_data, data); 4933 if (ret) 4934 break; 4935 } else if (data->handler == HANDLER_ONMAX || 4936 data->handler == HANDLER_ONCHANGE) { 4937 ret = track_data_create(hist_data, data); 4938 if (ret) 4939 break; 4940 } else { 4941 ret = -EINVAL; 4942 break; 4943 } 4944 } 4945 4946 return ret; 4947 } 4948 4949 static void print_actions(struct seq_file *m, 4950 struct hist_trigger_data *hist_data, 4951 struct tracing_map_elt *elt) 4952 { 4953 unsigned int i; 4954 4955 for (i = 0; i < hist_data->n_actions; i++) { 4956 struct action_data *data = hist_data->actions[i]; 4957 4958 if (data->action == ACTION_SNAPSHOT) 4959 continue; 4960 4961 if (data->handler == HANDLER_ONMAX || 4962 data->handler == HANDLER_ONCHANGE) 4963 track_data_print(m, hist_data, elt, data); 4964 } 4965 } 4966 4967 static void print_action_spec(struct seq_file *m, 4968 struct hist_trigger_data *hist_data, 4969 struct action_data *data) 4970 { 4971 unsigned int i; 4972 4973 if (data->action == ACTION_SAVE) { 4974 for (i = 0; i < hist_data->n_save_vars; i++) { 4975 seq_printf(m, "%s", hist_data->save_vars[i]->var->var.name); 4976 if (i < hist_data->n_save_vars - 1) 4977 seq_puts(m, ","); 4978 } 4979 } else if (data->action == ACTION_TRACE) { 4980 if (data->use_trace_keyword) 4981 seq_printf(m, "%s", data->synth_event_name); 4982 for (i = 0; i < data->n_params; i++) { 4983 if (i || data->use_trace_keyword) 4984 seq_puts(m, ","); 4985 seq_printf(m, "%s", data->params[i]); 4986 } 4987 } 4988 } 4989 4990 static void print_track_data_spec(struct seq_file *m, 4991 struct hist_trigger_data *hist_data, 4992 struct action_data *data) 4993 { 4994 if (data->handler == HANDLER_ONMAX) 4995 seq_puts(m, ":onmax("); 4996 else if (data->handler == HANDLER_ONCHANGE) 4997 seq_puts(m, ":onchange("); 4998 seq_printf(m, "%s", data->track_data.var_str); 4999 seq_printf(m, ").%s(", data->action_name); 5000 5001 print_action_spec(m, hist_data, data); 5002 5003 seq_puts(m, ")"); 5004 } 5005 5006 static void print_onmatch_spec(struct seq_file *m, 5007 struct hist_trigger_data *hist_data, 5008 struct action_data *data) 5009 { 5010 seq_printf(m, ":onmatch(%s.%s).", data->match_data.event_system, 5011 data->match_data.event); 5012 5013 seq_printf(m, "%s(", data->action_name); 5014 5015 print_action_spec(m, hist_data, data); 5016 5017 seq_puts(m, ")"); 5018 } 5019 5020 static bool actions_match(struct hist_trigger_data *hist_data, 5021 struct hist_trigger_data *hist_data_test) 5022 { 5023 unsigned int i, j; 5024 5025 if (hist_data->n_actions != hist_data_test->n_actions) 5026 return false; 5027 5028 for (i = 0; i < hist_data->n_actions; i++) { 5029 struct action_data *data = hist_data->actions[i]; 5030 struct action_data *data_test = hist_data_test->actions[i]; 5031 char *action_name, *action_name_test; 5032 5033 if (data->handler != data_test->handler) 5034 return false; 5035 if (data->action != data_test->action) 5036 return false; 5037 5038 if (data->n_params != data_test->n_params) 5039 return false; 5040 5041 for (j = 0; j < data->n_params; j++) { 5042 if (strcmp(data->params[j], data_test->params[j]) != 0) 5043 return false; 5044 } 5045 5046 if (data->use_trace_keyword) 5047 action_name = data->synth_event_name; 5048 else 5049 action_name = data->action_name; 5050 5051 if (data_test->use_trace_keyword) 5052 action_name_test = data_test->synth_event_name; 5053 else 5054 action_name_test = data_test->action_name; 5055 5056 if (strcmp(action_name, action_name_test) != 0) 5057 return false; 5058 5059 if (data->handler == HANDLER_ONMATCH) { 5060 if (strcmp(data->match_data.event_system, 5061 data_test->match_data.event_system) != 0) 5062 return false; 5063 if (strcmp(data->match_data.event, 5064 data_test->match_data.event) != 0) 5065 return false; 5066 } else if (data->handler == HANDLER_ONMAX || 5067 data->handler == HANDLER_ONCHANGE) { 5068 if (strcmp(data->track_data.var_str, 5069 data_test->track_data.var_str) != 0) 5070 return false; 5071 } 5072 } 5073 5074 return true; 5075 } 5076 5077 5078 static void print_actions_spec(struct seq_file *m, 5079 struct hist_trigger_data *hist_data) 5080 { 5081 unsigned int i; 5082 5083 for (i = 0; i < hist_data->n_actions; i++) { 5084 struct action_data *data = hist_data->actions[i]; 5085 5086 if (data->handler == HANDLER_ONMATCH) 5087 print_onmatch_spec(m, hist_data, data); 5088 else if (data->handler == HANDLER_ONMAX || 5089 data->handler == HANDLER_ONCHANGE) 5090 print_track_data_spec(m, hist_data, data); 5091 } 5092 } 5093 5094 static void destroy_field_var_hists(struct hist_trigger_data *hist_data) 5095 { 5096 unsigned int i; 5097 5098 for (i = 0; i < hist_data->n_field_var_hists; i++) { 5099 kfree(hist_data->field_var_hists[i]->cmd); 5100 kfree(hist_data->field_var_hists[i]); 5101 } 5102 } 5103 5104 static void destroy_hist_data(struct hist_trigger_data *hist_data) 5105 { 5106 if (!hist_data) 5107 return; 5108 5109 destroy_hist_trigger_attrs(hist_data->attrs); 5110 destroy_hist_fields(hist_data); 5111 tracing_map_destroy(hist_data->map); 5112 5113 destroy_actions(hist_data); 5114 destroy_field_vars(hist_data); 5115 destroy_field_var_hists(hist_data); 5116 5117 kfree(hist_data); 5118 } 5119 5120 static int create_tracing_map_fields(struct hist_trigger_data *hist_data) 5121 { 5122 struct tracing_map *map = hist_data->map; 5123 struct ftrace_event_field *field; 5124 struct hist_field *hist_field; 5125 int i, idx = 0; 5126 5127 for_each_hist_field(i, hist_data) { 5128 hist_field = hist_data->fields[i]; 5129 if (hist_field->flags & HIST_FIELD_FL_KEY) { 5130 tracing_map_cmp_fn_t cmp_fn; 5131 5132 field = hist_field->field; 5133 5134 if (hist_field->flags & HIST_FIELD_FL_STACKTRACE) 5135 cmp_fn = tracing_map_cmp_none; 5136 else if (!field) 5137 cmp_fn = tracing_map_cmp_num(hist_field->size, 5138 hist_field->is_signed); 5139 else if (is_string_field(field)) 5140 cmp_fn = tracing_map_cmp_string; 5141 else 5142 cmp_fn = tracing_map_cmp_num(field->size, 5143 field->is_signed); 5144 idx = tracing_map_add_key_field(map, 5145 hist_field->offset, 5146 cmp_fn); 5147 } else if (!(hist_field->flags & HIST_FIELD_FL_VAR)) 5148 idx = tracing_map_add_sum_field(map); 5149 5150 if (idx < 0) 5151 return idx; 5152 5153 if (hist_field->flags & HIST_FIELD_FL_VAR) { 5154 idx = tracing_map_add_var(map); 5155 if (idx < 0) 5156 return idx; 5157 hist_field->var.idx = idx; 5158 hist_field->var.hist_data = hist_data; 5159 } 5160 } 5161 5162 return 0; 5163 } 5164 5165 static struct hist_trigger_data * 5166 create_hist_data(unsigned int map_bits, 5167 struct hist_trigger_attrs *attrs, 5168 struct trace_event_file *file, 5169 bool remove) 5170 { 5171 const struct tracing_map_ops *map_ops = NULL; 5172 struct hist_trigger_data *hist_data; 5173 int ret = 0; 5174 5175 hist_data = kzalloc(sizeof(*hist_data), GFP_KERNEL); 5176 if (!hist_data) 5177 return ERR_PTR(-ENOMEM); 5178 5179 hist_data->attrs = attrs; 5180 hist_data->remove = remove; 5181 hist_data->event_file = file; 5182 5183 ret = parse_actions(hist_data); 5184 if (ret) 5185 goto free; 5186 5187 ret = create_hist_fields(hist_data, file); 5188 if (ret) 5189 goto free; 5190 5191 ret = create_sort_keys(hist_data); 5192 if (ret) 5193 goto free; 5194 5195 map_ops = &hist_trigger_elt_data_ops; 5196 5197 hist_data->map = tracing_map_create(map_bits, hist_data->key_size, 5198 map_ops, hist_data); 5199 if (IS_ERR(hist_data->map)) { 5200 ret = PTR_ERR(hist_data->map); 5201 hist_data->map = NULL; 5202 goto free; 5203 } 5204 5205 ret = create_tracing_map_fields(hist_data); 5206 if (ret) 5207 goto free; 5208 out: 5209 return hist_data; 5210 free: 5211 hist_data->attrs = NULL; 5212 5213 destroy_hist_data(hist_data); 5214 5215 hist_data = ERR_PTR(ret); 5216 5217 goto out; 5218 } 5219 5220 static void hist_trigger_elt_update(struct hist_trigger_data *hist_data, 5221 struct tracing_map_elt *elt, void *rec, 5222 struct ring_buffer_event *rbe, 5223 u64 *var_ref_vals) 5224 { 5225 struct hist_elt_data *elt_data; 5226 struct hist_field *hist_field; 5227 unsigned int i, var_idx; 5228 u64 hist_val; 5229 5230 elt_data = elt->private_data; 5231 elt_data->var_ref_vals = var_ref_vals; 5232 5233 for_each_hist_val_field(i, hist_data) { 5234 hist_field = hist_data->fields[i]; 5235 hist_val = hist_field->fn(hist_field, elt, rbe, rec); 5236 if (hist_field->flags & HIST_FIELD_FL_VAR) { 5237 var_idx = hist_field->var.idx; 5238 tracing_map_set_var(elt, var_idx, hist_val); 5239 continue; 5240 } 5241 tracing_map_update_sum(elt, i, hist_val); 5242 } 5243 5244 for_each_hist_key_field(i, hist_data) { 5245 hist_field = hist_data->fields[i]; 5246 if (hist_field->flags & HIST_FIELD_FL_VAR) { 5247 hist_val = hist_field->fn(hist_field, elt, rbe, rec); 5248 var_idx = hist_field->var.idx; 5249 tracing_map_set_var(elt, var_idx, hist_val); 5250 } 5251 } 5252 5253 update_field_vars(hist_data, elt, rbe, rec); 5254 } 5255 5256 static inline void add_to_key(char *compound_key, void *key, 5257 struct hist_field *key_field, void *rec) 5258 { 5259 size_t size = key_field->size; 5260 5261 if (key_field->flags & HIST_FIELD_FL_STRING) { 5262 struct ftrace_event_field *field; 5263 5264 field = key_field->field; 5265 if (field->filter_type == FILTER_DYN_STRING) 5266 size = *(u32 *)(rec + field->offset) >> 16; 5267 else if (field->filter_type == FILTER_PTR_STRING) 5268 size = strlen(key); 5269 else if (field->filter_type == FILTER_STATIC_STRING) 5270 size = field->size; 5271 5272 /* ensure NULL-termination */ 5273 if (size > key_field->size - 1) 5274 size = key_field->size - 1; 5275 5276 strncpy(compound_key + key_field->offset, (char *)key, size); 5277 } else 5278 memcpy(compound_key + key_field->offset, key, size); 5279 } 5280 5281 static void 5282 hist_trigger_actions(struct hist_trigger_data *hist_data, 5283 struct tracing_map_elt *elt, void *rec, 5284 struct ring_buffer_event *rbe, void *key, 5285 u64 *var_ref_vals) 5286 { 5287 struct action_data *data; 5288 unsigned int i; 5289 5290 for (i = 0; i < hist_data->n_actions; i++) { 5291 data = hist_data->actions[i]; 5292 data->fn(hist_data, elt, rec, rbe, key, data, var_ref_vals); 5293 } 5294 } 5295 5296 static void event_hist_trigger(struct event_trigger_data *data, void *rec, 5297 struct ring_buffer_event *rbe) 5298 { 5299 struct hist_trigger_data *hist_data = data->private_data; 5300 bool use_compound_key = (hist_data->n_keys > 1); 5301 unsigned long entries[HIST_STACKTRACE_DEPTH]; 5302 u64 var_ref_vals[TRACING_MAP_VARS_MAX]; 5303 char compound_key[HIST_KEY_SIZE_MAX]; 5304 struct tracing_map_elt *elt = NULL; 5305 struct hist_field *key_field; 5306 u64 field_contents; 5307 void *key = NULL; 5308 unsigned int i; 5309 5310 memset(compound_key, 0, hist_data->key_size); 5311 5312 for_each_hist_key_field(i, hist_data) { 5313 key_field = hist_data->fields[i]; 5314 5315 if (key_field->flags & HIST_FIELD_FL_STACKTRACE) { 5316 memset(entries, 0, HIST_STACKTRACE_SIZE); 5317 stack_trace_save(entries, HIST_STACKTRACE_DEPTH, 5318 HIST_STACKTRACE_SKIP); 5319 key = entries; 5320 } else { 5321 field_contents = key_field->fn(key_field, elt, rbe, rec); 5322 if (key_field->flags & HIST_FIELD_FL_STRING) { 5323 key = (void *)(unsigned long)field_contents; 5324 use_compound_key = true; 5325 } else 5326 key = (void *)&field_contents; 5327 } 5328 5329 if (use_compound_key) 5330 add_to_key(compound_key, key, key_field, rec); 5331 } 5332 5333 if (use_compound_key) 5334 key = compound_key; 5335 5336 if (hist_data->n_var_refs && 5337 !resolve_var_refs(hist_data, key, var_ref_vals, false)) 5338 return; 5339 5340 elt = tracing_map_insert(hist_data->map, key); 5341 if (!elt) 5342 return; 5343 5344 hist_trigger_elt_update(hist_data, elt, rec, rbe, var_ref_vals); 5345 5346 if (resolve_var_refs(hist_data, key, var_ref_vals, true)) 5347 hist_trigger_actions(hist_data, elt, rec, rbe, key, var_ref_vals); 5348 } 5349 5350 static void hist_trigger_stacktrace_print(struct seq_file *m, 5351 unsigned long *stacktrace_entries, 5352 unsigned int max_entries) 5353 { 5354 char str[KSYM_SYMBOL_LEN]; 5355 unsigned int spaces = 8; 5356 unsigned int i; 5357 5358 for (i = 0; i < max_entries; i++) { 5359 if (!stacktrace_entries[i]) 5360 return; 5361 5362 seq_printf(m, "%*c", 1 + spaces, ' '); 5363 sprint_symbol(str, stacktrace_entries[i]); 5364 seq_printf(m, "%s\n", str); 5365 } 5366 } 5367 5368 static void hist_trigger_print_key(struct seq_file *m, 5369 struct hist_trigger_data *hist_data, 5370 void *key, 5371 struct tracing_map_elt *elt) 5372 { 5373 struct hist_field *key_field; 5374 char str[KSYM_SYMBOL_LEN]; 5375 bool multiline = false; 5376 const char *field_name; 5377 unsigned int i; 5378 u64 uval; 5379 5380 seq_puts(m, "{ "); 5381 5382 for_each_hist_key_field(i, hist_data) { 5383 key_field = hist_data->fields[i]; 5384 5385 if (i > hist_data->n_vals) 5386 seq_puts(m, ", "); 5387 5388 field_name = hist_field_name(key_field, 0); 5389 5390 if (key_field->flags & HIST_FIELD_FL_HEX) { 5391 uval = *(u64 *)(key + key_field->offset); 5392 seq_printf(m, "%s: %llx", field_name, uval); 5393 } else if (key_field->flags & HIST_FIELD_FL_SYM) { 5394 uval = *(u64 *)(key + key_field->offset); 5395 sprint_symbol_no_offset(str, uval); 5396 seq_printf(m, "%s: [%llx] %-45s", field_name, 5397 uval, str); 5398 } else if (key_field->flags & HIST_FIELD_FL_SYM_OFFSET) { 5399 uval = *(u64 *)(key + key_field->offset); 5400 sprint_symbol(str, uval); 5401 seq_printf(m, "%s: [%llx] %-55s", field_name, 5402 uval, str); 5403 } else if (key_field->flags & HIST_FIELD_FL_EXECNAME) { 5404 struct hist_elt_data *elt_data = elt->private_data; 5405 char *comm; 5406 5407 if (WARN_ON_ONCE(!elt_data)) 5408 return; 5409 5410 comm = elt_data->comm; 5411 5412 uval = *(u64 *)(key + key_field->offset); 5413 seq_printf(m, "%s: %-16s[%10llu]", field_name, 5414 comm, uval); 5415 } else if (key_field->flags & HIST_FIELD_FL_SYSCALL) { 5416 const char *syscall_name; 5417 5418 uval = *(u64 *)(key + key_field->offset); 5419 syscall_name = get_syscall_name(uval); 5420 if (!syscall_name) 5421 syscall_name = "unknown_syscall"; 5422 5423 seq_printf(m, "%s: %-30s[%3llu]", field_name, 5424 syscall_name, uval); 5425 } else if (key_field->flags & HIST_FIELD_FL_STACKTRACE) { 5426 seq_puts(m, "stacktrace:\n"); 5427 hist_trigger_stacktrace_print(m, 5428 key + key_field->offset, 5429 HIST_STACKTRACE_DEPTH); 5430 multiline = true; 5431 } else if (key_field->flags & HIST_FIELD_FL_LOG2) { 5432 seq_printf(m, "%s: ~ 2^%-2llu", field_name, 5433 *(u64 *)(key + key_field->offset)); 5434 } else if (key_field->flags & HIST_FIELD_FL_STRING) { 5435 seq_printf(m, "%s: %-50s", field_name, 5436 (char *)(key + key_field->offset)); 5437 } else { 5438 uval = *(u64 *)(key + key_field->offset); 5439 seq_printf(m, "%s: %10llu", field_name, uval); 5440 } 5441 } 5442 5443 if (!multiline) 5444 seq_puts(m, " "); 5445 5446 seq_puts(m, "}"); 5447 } 5448 5449 static void hist_trigger_entry_print(struct seq_file *m, 5450 struct hist_trigger_data *hist_data, 5451 void *key, 5452 struct tracing_map_elt *elt) 5453 { 5454 const char *field_name; 5455 unsigned int i; 5456 5457 hist_trigger_print_key(m, hist_data, key, elt); 5458 5459 seq_printf(m, " hitcount: %10llu", 5460 tracing_map_read_sum(elt, HITCOUNT_IDX)); 5461 5462 for (i = 1; i < hist_data->n_vals; i++) { 5463 field_name = hist_field_name(hist_data->fields[i], 0); 5464 5465 if (hist_data->fields[i]->flags & HIST_FIELD_FL_VAR || 5466 hist_data->fields[i]->flags & HIST_FIELD_FL_EXPR) 5467 continue; 5468 5469 if (hist_data->fields[i]->flags & HIST_FIELD_FL_HEX) { 5470 seq_printf(m, " %s: %10llx", field_name, 5471 tracing_map_read_sum(elt, i)); 5472 } else { 5473 seq_printf(m, " %s: %10llu", field_name, 5474 tracing_map_read_sum(elt, i)); 5475 } 5476 } 5477 5478 print_actions(m, hist_data, elt); 5479 5480 seq_puts(m, "\n"); 5481 } 5482 5483 static int print_entries(struct seq_file *m, 5484 struct hist_trigger_data *hist_data) 5485 { 5486 struct tracing_map_sort_entry **sort_entries = NULL; 5487 struct tracing_map *map = hist_data->map; 5488 int i, n_entries; 5489 5490 n_entries = tracing_map_sort_entries(map, hist_data->sort_keys, 5491 hist_data->n_sort_keys, 5492 &sort_entries); 5493 if (n_entries < 0) 5494 return n_entries; 5495 5496 for (i = 0; i < n_entries; i++) 5497 hist_trigger_entry_print(m, hist_data, 5498 sort_entries[i]->key, 5499 sort_entries[i]->elt); 5500 5501 tracing_map_destroy_sort_entries(sort_entries, n_entries); 5502 5503 return n_entries; 5504 } 5505 5506 static void hist_trigger_show(struct seq_file *m, 5507 struct event_trigger_data *data, int n) 5508 { 5509 struct hist_trigger_data *hist_data; 5510 int n_entries; 5511 5512 if (n > 0) 5513 seq_puts(m, "\n\n"); 5514 5515 seq_puts(m, "# event histogram\n#\n# trigger info: "); 5516 data->ops->print(m, data->ops, data); 5517 seq_puts(m, "#\n\n"); 5518 5519 hist_data = data->private_data; 5520 n_entries = print_entries(m, hist_data); 5521 if (n_entries < 0) 5522 n_entries = 0; 5523 5524 track_data_snapshot_print(m, hist_data); 5525 5526 seq_printf(m, "\nTotals:\n Hits: %llu\n Entries: %u\n Dropped: %llu\n", 5527 (u64)atomic64_read(&hist_data->map->hits), 5528 n_entries, (u64)atomic64_read(&hist_data->map->drops)); 5529 } 5530 5531 static int hist_show(struct seq_file *m, void *v) 5532 { 5533 struct event_trigger_data *data; 5534 struct trace_event_file *event_file; 5535 int n = 0, ret = 0; 5536 5537 mutex_lock(&event_mutex); 5538 5539 event_file = event_file_data(m->private); 5540 if (unlikely(!event_file)) { 5541 ret = -ENODEV; 5542 goto out_unlock; 5543 } 5544 5545 list_for_each_entry(data, &event_file->triggers, list) { 5546 if (data->cmd_ops->trigger_type == ETT_EVENT_HIST) 5547 hist_trigger_show(m, data, n++); 5548 } 5549 5550 out_unlock: 5551 mutex_unlock(&event_mutex); 5552 5553 return ret; 5554 } 5555 5556 static int event_hist_open(struct inode *inode, struct file *file) 5557 { 5558 int ret; 5559 5560 ret = security_locked_down(LOCKDOWN_TRACEFS); 5561 if (ret) 5562 return ret; 5563 5564 return single_open(file, hist_show, file); 5565 } 5566 5567 const struct file_operations event_hist_fops = { 5568 .open = event_hist_open, 5569 .read = seq_read, 5570 .llseek = seq_lseek, 5571 .release = single_release, 5572 }; 5573 5574 static void hist_field_print(struct seq_file *m, struct hist_field *hist_field) 5575 { 5576 const char *field_name = hist_field_name(hist_field, 0); 5577 5578 if (hist_field->var.name) 5579 seq_printf(m, "%s=", hist_field->var.name); 5580 5581 if (hist_field->flags & HIST_FIELD_FL_CPU) 5582 seq_puts(m, "cpu"); 5583 else if (field_name) { 5584 if (hist_field->flags & HIST_FIELD_FL_VAR_REF || 5585 hist_field->flags & HIST_FIELD_FL_ALIAS) 5586 seq_putc(m, '$'); 5587 seq_printf(m, "%s", field_name); 5588 } else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP) 5589 seq_puts(m, "common_timestamp"); 5590 5591 if (hist_field->flags) { 5592 if (!(hist_field->flags & HIST_FIELD_FL_VAR_REF) && 5593 !(hist_field->flags & HIST_FIELD_FL_EXPR)) { 5594 const char *flags = get_hist_field_flags(hist_field); 5595 5596 if (flags) 5597 seq_printf(m, ".%s", flags); 5598 } 5599 } 5600 } 5601 5602 static int event_hist_trigger_print(struct seq_file *m, 5603 struct event_trigger_ops *ops, 5604 struct event_trigger_data *data) 5605 { 5606 struct hist_trigger_data *hist_data = data->private_data; 5607 struct hist_field *field; 5608 bool have_var = false; 5609 unsigned int i; 5610 5611 seq_puts(m, "hist:"); 5612 5613 if (data->name) 5614 seq_printf(m, "%s:", data->name); 5615 5616 seq_puts(m, "keys="); 5617 5618 for_each_hist_key_field(i, hist_data) { 5619 field = hist_data->fields[i]; 5620 5621 if (i > hist_data->n_vals) 5622 seq_puts(m, ","); 5623 5624 if (field->flags & HIST_FIELD_FL_STACKTRACE) 5625 seq_puts(m, "stacktrace"); 5626 else 5627 hist_field_print(m, field); 5628 } 5629 5630 seq_puts(m, ":vals="); 5631 5632 for_each_hist_val_field(i, hist_data) { 5633 field = hist_data->fields[i]; 5634 if (field->flags & HIST_FIELD_FL_VAR) { 5635 have_var = true; 5636 continue; 5637 } 5638 5639 if (i == HITCOUNT_IDX) 5640 seq_puts(m, "hitcount"); 5641 else { 5642 seq_puts(m, ","); 5643 hist_field_print(m, field); 5644 } 5645 } 5646 5647 if (have_var) { 5648 unsigned int n = 0; 5649 5650 seq_puts(m, ":"); 5651 5652 for_each_hist_val_field(i, hist_data) { 5653 field = hist_data->fields[i]; 5654 5655 if (field->flags & HIST_FIELD_FL_VAR) { 5656 if (n++) 5657 seq_puts(m, ","); 5658 hist_field_print(m, field); 5659 } 5660 } 5661 } 5662 5663 seq_puts(m, ":sort="); 5664 5665 for (i = 0; i < hist_data->n_sort_keys; i++) { 5666 struct tracing_map_sort_key *sort_key; 5667 unsigned int idx, first_key_idx; 5668 5669 /* skip VAR vals */ 5670 first_key_idx = hist_data->n_vals - hist_data->n_vars; 5671 5672 sort_key = &hist_data->sort_keys[i]; 5673 idx = sort_key->field_idx; 5674 5675 if (WARN_ON(idx >= HIST_FIELDS_MAX)) 5676 return -EINVAL; 5677 5678 if (i > 0) 5679 seq_puts(m, ","); 5680 5681 if (idx == HITCOUNT_IDX) 5682 seq_puts(m, "hitcount"); 5683 else { 5684 if (idx >= first_key_idx) 5685 idx += hist_data->n_vars; 5686 hist_field_print(m, hist_data->fields[idx]); 5687 } 5688 5689 if (sort_key->descending) 5690 seq_puts(m, ".descending"); 5691 } 5692 seq_printf(m, ":size=%u", (1 << hist_data->map->map_bits)); 5693 if (hist_data->enable_timestamps) 5694 seq_printf(m, ":clock=%s", hist_data->attrs->clock); 5695 5696 print_actions_spec(m, hist_data); 5697 5698 if (data->filter_str) 5699 seq_printf(m, " if %s", data->filter_str); 5700 5701 if (data->paused) 5702 seq_puts(m, " [paused]"); 5703 else 5704 seq_puts(m, " [active]"); 5705 5706 seq_putc(m, '\n'); 5707 5708 return 0; 5709 } 5710 5711 static int event_hist_trigger_init(struct event_trigger_ops *ops, 5712 struct event_trigger_data *data) 5713 { 5714 struct hist_trigger_data *hist_data = data->private_data; 5715 5716 if (!data->ref && hist_data->attrs->name) 5717 save_named_trigger(hist_data->attrs->name, data); 5718 5719 data->ref++; 5720 5721 return 0; 5722 } 5723 5724 static void unregister_field_var_hists(struct hist_trigger_data *hist_data) 5725 { 5726 struct trace_event_file *file; 5727 unsigned int i; 5728 char *cmd; 5729 int ret; 5730 5731 for (i = 0; i < hist_data->n_field_var_hists; i++) { 5732 file = hist_data->field_var_hists[i]->hist_data->event_file; 5733 cmd = hist_data->field_var_hists[i]->cmd; 5734 ret = event_hist_trigger_func(&trigger_hist_cmd, file, 5735 "!hist", "hist", cmd); 5736 } 5737 } 5738 5739 static void event_hist_trigger_free(struct event_trigger_ops *ops, 5740 struct event_trigger_data *data) 5741 { 5742 struct hist_trigger_data *hist_data = data->private_data; 5743 5744 if (WARN_ON_ONCE(data->ref <= 0)) 5745 return; 5746 5747 data->ref--; 5748 if (!data->ref) { 5749 if (data->name) 5750 del_named_trigger(data); 5751 5752 trigger_data_free(data); 5753 5754 remove_hist_vars(hist_data); 5755 5756 unregister_field_var_hists(hist_data); 5757 5758 destroy_hist_data(hist_data); 5759 } 5760 } 5761 5762 static struct event_trigger_ops event_hist_trigger_ops = { 5763 .func = event_hist_trigger, 5764 .print = event_hist_trigger_print, 5765 .init = event_hist_trigger_init, 5766 .free = event_hist_trigger_free, 5767 }; 5768 5769 static int event_hist_trigger_named_init(struct event_trigger_ops *ops, 5770 struct event_trigger_data *data) 5771 { 5772 data->ref++; 5773 5774 save_named_trigger(data->named_data->name, data); 5775 5776 event_hist_trigger_init(ops, data->named_data); 5777 5778 return 0; 5779 } 5780 5781 static void event_hist_trigger_named_free(struct event_trigger_ops *ops, 5782 struct event_trigger_data *data) 5783 { 5784 if (WARN_ON_ONCE(data->ref <= 0)) 5785 return; 5786 5787 event_hist_trigger_free(ops, data->named_data); 5788 5789 data->ref--; 5790 if (!data->ref) { 5791 del_named_trigger(data); 5792 trigger_data_free(data); 5793 } 5794 } 5795 5796 static struct event_trigger_ops event_hist_trigger_named_ops = { 5797 .func = event_hist_trigger, 5798 .print = event_hist_trigger_print, 5799 .init = event_hist_trigger_named_init, 5800 .free = event_hist_trigger_named_free, 5801 }; 5802 5803 static struct event_trigger_ops *event_hist_get_trigger_ops(char *cmd, 5804 char *param) 5805 { 5806 return &event_hist_trigger_ops; 5807 } 5808 5809 static void hist_clear(struct event_trigger_data *data) 5810 { 5811 struct hist_trigger_data *hist_data = data->private_data; 5812 5813 if (data->name) 5814 pause_named_trigger(data); 5815 5816 tracepoint_synchronize_unregister(); 5817 5818 tracing_map_clear(hist_data->map); 5819 5820 if (data->name) 5821 unpause_named_trigger(data); 5822 } 5823 5824 static bool compatible_field(struct ftrace_event_field *field, 5825 struct ftrace_event_field *test_field) 5826 { 5827 if (field == test_field) 5828 return true; 5829 if (field == NULL || test_field == NULL) 5830 return false; 5831 if (strcmp(field->name, test_field->name) != 0) 5832 return false; 5833 if (strcmp(field->type, test_field->type) != 0) 5834 return false; 5835 if (field->size != test_field->size) 5836 return false; 5837 if (field->is_signed != test_field->is_signed) 5838 return false; 5839 5840 return true; 5841 } 5842 5843 static bool hist_trigger_match(struct event_trigger_data *data, 5844 struct event_trigger_data *data_test, 5845 struct event_trigger_data *named_data, 5846 bool ignore_filter) 5847 { 5848 struct tracing_map_sort_key *sort_key, *sort_key_test; 5849 struct hist_trigger_data *hist_data, *hist_data_test; 5850 struct hist_field *key_field, *key_field_test; 5851 unsigned int i; 5852 5853 if (named_data && (named_data != data_test) && 5854 (named_data != data_test->named_data)) 5855 return false; 5856 5857 if (!named_data && is_named_trigger(data_test)) 5858 return false; 5859 5860 hist_data = data->private_data; 5861 hist_data_test = data_test->private_data; 5862 5863 if (hist_data->n_vals != hist_data_test->n_vals || 5864 hist_data->n_fields != hist_data_test->n_fields || 5865 hist_data->n_sort_keys != hist_data_test->n_sort_keys) 5866 return false; 5867 5868 if (!ignore_filter) { 5869 if ((data->filter_str && !data_test->filter_str) || 5870 (!data->filter_str && data_test->filter_str)) 5871 return false; 5872 } 5873 5874 for_each_hist_field(i, hist_data) { 5875 key_field = hist_data->fields[i]; 5876 key_field_test = hist_data_test->fields[i]; 5877 5878 if (key_field->flags != key_field_test->flags) 5879 return false; 5880 if (!compatible_field(key_field->field, key_field_test->field)) 5881 return false; 5882 if (key_field->offset != key_field_test->offset) 5883 return false; 5884 if (key_field->size != key_field_test->size) 5885 return false; 5886 if (key_field->is_signed != key_field_test->is_signed) 5887 return false; 5888 if (!!key_field->var.name != !!key_field_test->var.name) 5889 return false; 5890 if (key_field->var.name && 5891 strcmp(key_field->var.name, key_field_test->var.name) != 0) 5892 return false; 5893 } 5894 5895 for (i = 0; i < hist_data->n_sort_keys; i++) { 5896 sort_key = &hist_data->sort_keys[i]; 5897 sort_key_test = &hist_data_test->sort_keys[i]; 5898 5899 if (sort_key->field_idx != sort_key_test->field_idx || 5900 sort_key->descending != sort_key_test->descending) 5901 return false; 5902 } 5903 5904 if (!ignore_filter && data->filter_str && 5905 (strcmp(data->filter_str, data_test->filter_str) != 0)) 5906 return false; 5907 5908 if (!actions_match(hist_data, hist_data_test)) 5909 return false; 5910 5911 return true; 5912 } 5913 5914 static int hist_register_trigger(char *glob, struct event_trigger_ops *ops, 5915 struct event_trigger_data *data, 5916 struct trace_event_file *file) 5917 { 5918 struct hist_trigger_data *hist_data = data->private_data; 5919 struct event_trigger_data *test, *named_data = NULL; 5920 struct trace_array *tr = file->tr; 5921 int ret = 0; 5922 5923 if (hist_data->attrs->name) { 5924 named_data = find_named_trigger(hist_data->attrs->name); 5925 if (named_data) { 5926 if (!hist_trigger_match(data, named_data, named_data, 5927 true)) { 5928 hist_err(tr, HIST_ERR_NAMED_MISMATCH, errpos(hist_data->attrs->name)); 5929 ret = -EINVAL; 5930 goto out; 5931 } 5932 } 5933 } 5934 5935 if (hist_data->attrs->name && !named_data) 5936 goto new; 5937 5938 lockdep_assert_held(&event_mutex); 5939 5940 list_for_each_entry(test, &file->triggers, list) { 5941 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 5942 if (!hist_trigger_match(data, test, named_data, false)) 5943 continue; 5944 if (hist_data->attrs->pause) 5945 test->paused = true; 5946 else if (hist_data->attrs->cont) 5947 test->paused = false; 5948 else if (hist_data->attrs->clear) 5949 hist_clear(test); 5950 else { 5951 hist_err(tr, HIST_ERR_TRIGGER_EEXIST, 0); 5952 ret = -EEXIST; 5953 } 5954 goto out; 5955 } 5956 } 5957 new: 5958 if (hist_data->attrs->cont || hist_data->attrs->clear) { 5959 hist_err(tr, HIST_ERR_TRIGGER_ENOENT_CLEAR, 0); 5960 ret = -ENOENT; 5961 goto out; 5962 } 5963 5964 if (hist_data->attrs->pause) 5965 data->paused = true; 5966 5967 if (named_data) { 5968 data->private_data = named_data->private_data; 5969 set_named_trigger_data(data, named_data); 5970 data->ops = &event_hist_trigger_named_ops; 5971 } 5972 5973 if (data->ops->init) { 5974 ret = data->ops->init(data->ops, data); 5975 if (ret < 0) 5976 goto out; 5977 } 5978 5979 if (hist_data->enable_timestamps) { 5980 char *clock = hist_data->attrs->clock; 5981 5982 ret = tracing_set_clock(file->tr, hist_data->attrs->clock); 5983 if (ret) { 5984 hist_err(tr, HIST_ERR_SET_CLOCK_FAIL, errpos(clock)); 5985 goto out; 5986 } 5987 5988 tracing_set_time_stamp_abs(file->tr, true); 5989 } 5990 5991 if (named_data) 5992 destroy_hist_data(hist_data); 5993 5994 ret++; 5995 out: 5996 return ret; 5997 } 5998 5999 static int hist_trigger_enable(struct event_trigger_data *data, 6000 struct trace_event_file *file) 6001 { 6002 int ret = 0; 6003 6004 list_add_tail_rcu(&data->list, &file->triggers); 6005 6006 update_cond_flag(file); 6007 6008 if (trace_event_trigger_enable_disable(file, 1) < 0) { 6009 list_del_rcu(&data->list); 6010 update_cond_flag(file); 6011 ret--; 6012 } 6013 6014 return ret; 6015 } 6016 6017 static bool have_hist_trigger_match(struct event_trigger_data *data, 6018 struct trace_event_file *file) 6019 { 6020 struct hist_trigger_data *hist_data = data->private_data; 6021 struct event_trigger_data *test, *named_data = NULL; 6022 bool match = false; 6023 6024 lockdep_assert_held(&event_mutex); 6025 6026 if (hist_data->attrs->name) 6027 named_data = find_named_trigger(hist_data->attrs->name); 6028 6029 list_for_each_entry(test, &file->triggers, list) { 6030 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6031 if (hist_trigger_match(data, test, named_data, false)) { 6032 match = true; 6033 break; 6034 } 6035 } 6036 } 6037 6038 return match; 6039 } 6040 6041 static bool hist_trigger_check_refs(struct event_trigger_data *data, 6042 struct trace_event_file *file) 6043 { 6044 struct hist_trigger_data *hist_data = data->private_data; 6045 struct event_trigger_data *test, *named_data = NULL; 6046 6047 lockdep_assert_held(&event_mutex); 6048 6049 if (hist_data->attrs->name) 6050 named_data = find_named_trigger(hist_data->attrs->name); 6051 6052 list_for_each_entry(test, &file->triggers, list) { 6053 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6054 if (!hist_trigger_match(data, test, named_data, false)) 6055 continue; 6056 hist_data = test->private_data; 6057 if (check_var_refs(hist_data)) 6058 return true; 6059 break; 6060 } 6061 } 6062 6063 return false; 6064 } 6065 6066 static void hist_unregister_trigger(char *glob, struct event_trigger_ops *ops, 6067 struct event_trigger_data *data, 6068 struct trace_event_file *file) 6069 { 6070 struct hist_trigger_data *hist_data = data->private_data; 6071 struct event_trigger_data *test, *named_data = NULL; 6072 bool unregistered = false; 6073 6074 lockdep_assert_held(&event_mutex); 6075 6076 if (hist_data->attrs->name) 6077 named_data = find_named_trigger(hist_data->attrs->name); 6078 6079 list_for_each_entry(test, &file->triggers, list) { 6080 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6081 if (!hist_trigger_match(data, test, named_data, false)) 6082 continue; 6083 unregistered = true; 6084 list_del_rcu(&test->list); 6085 trace_event_trigger_enable_disable(file, 0); 6086 update_cond_flag(file); 6087 break; 6088 } 6089 } 6090 6091 if (unregistered && test->ops->free) 6092 test->ops->free(test->ops, test); 6093 6094 if (hist_data->enable_timestamps) { 6095 if (!hist_data->remove || unregistered) 6096 tracing_set_time_stamp_abs(file->tr, false); 6097 } 6098 } 6099 6100 static bool hist_file_check_refs(struct trace_event_file *file) 6101 { 6102 struct hist_trigger_data *hist_data; 6103 struct event_trigger_data *test; 6104 6105 lockdep_assert_held(&event_mutex); 6106 6107 list_for_each_entry(test, &file->triggers, list) { 6108 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6109 hist_data = test->private_data; 6110 if (check_var_refs(hist_data)) 6111 return true; 6112 } 6113 } 6114 6115 return false; 6116 } 6117 6118 static void hist_unreg_all(struct trace_event_file *file) 6119 { 6120 struct event_trigger_data *test, *n; 6121 struct hist_trigger_data *hist_data; 6122 struct synth_event *se; 6123 const char *se_name; 6124 6125 lockdep_assert_held(&event_mutex); 6126 6127 if (hist_file_check_refs(file)) 6128 return; 6129 6130 list_for_each_entry_safe(test, n, &file->triggers, list) { 6131 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6132 hist_data = test->private_data; 6133 list_del_rcu(&test->list); 6134 trace_event_trigger_enable_disable(file, 0); 6135 6136 se_name = trace_event_name(file->event_call); 6137 se = find_synth_event(se_name); 6138 if (se) 6139 se->ref--; 6140 6141 update_cond_flag(file); 6142 if (hist_data->enable_timestamps) 6143 tracing_set_time_stamp_abs(file->tr, false); 6144 if (test->ops->free) 6145 test->ops->free(test->ops, test); 6146 } 6147 } 6148 } 6149 6150 static int event_hist_trigger_func(struct event_command *cmd_ops, 6151 struct trace_event_file *file, 6152 char *glob, char *cmd, char *param) 6153 { 6154 unsigned int hist_trigger_bits = TRACING_MAP_BITS_DEFAULT; 6155 struct event_trigger_data *trigger_data; 6156 struct hist_trigger_attrs *attrs; 6157 struct event_trigger_ops *trigger_ops; 6158 struct hist_trigger_data *hist_data; 6159 struct synth_event *se; 6160 const char *se_name; 6161 bool remove = false; 6162 char *trigger, *p; 6163 int ret = 0; 6164 6165 lockdep_assert_held(&event_mutex); 6166 6167 if (glob && strlen(glob)) { 6168 hist_err_clear(); 6169 last_cmd_set(file, param); 6170 } 6171 6172 if (!param) 6173 return -EINVAL; 6174 6175 if (glob[0] == '!') 6176 remove = true; 6177 6178 /* 6179 * separate the trigger from the filter (k:v [if filter]) 6180 * allowing for whitespace in the trigger 6181 */ 6182 p = trigger = param; 6183 do { 6184 p = strstr(p, "if"); 6185 if (!p) 6186 break; 6187 if (p == param) 6188 return -EINVAL; 6189 if (*(p - 1) != ' ' && *(p - 1) != '\t') { 6190 p++; 6191 continue; 6192 } 6193 if (p >= param + strlen(param) - (sizeof("if") - 1) - 1) 6194 return -EINVAL; 6195 if (*(p + sizeof("if") - 1) != ' ' && *(p + sizeof("if") - 1) != '\t') { 6196 p++; 6197 continue; 6198 } 6199 break; 6200 } while (p); 6201 6202 if (!p) 6203 param = NULL; 6204 else { 6205 *(p - 1) = '\0'; 6206 param = strstrip(p); 6207 trigger = strstrip(trigger); 6208 } 6209 6210 attrs = parse_hist_trigger_attrs(file->tr, trigger); 6211 if (IS_ERR(attrs)) 6212 return PTR_ERR(attrs); 6213 6214 if (attrs->map_bits) 6215 hist_trigger_bits = attrs->map_bits; 6216 6217 hist_data = create_hist_data(hist_trigger_bits, attrs, file, remove); 6218 if (IS_ERR(hist_data)) { 6219 destroy_hist_trigger_attrs(attrs); 6220 return PTR_ERR(hist_data); 6221 } 6222 6223 trigger_ops = cmd_ops->get_trigger_ops(cmd, trigger); 6224 6225 trigger_data = kzalloc(sizeof(*trigger_data), GFP_KERNEL); 6226 if (!trigger_data) { 6227 ret = -ENOMEM; 6228 goto out_free; 6229 } 6230 6231 trigger_data->count = -1; 6232 trigger_data->ops = trigger_ops; 6233 trigger_data->cmd_ops = cmd_ops; 6234 6235 INIT_LIST_HEAD(&trigger_data->list); 6236 RCU_INIT_POINTER(trigger_data->filter, NULL); 6237 6238 trigger_data->private_data = hist_data; 6239 6240 /* if param is non-empty, it's supposed to be a filter */ 6241 if (param && cmd_ops->set_filter) { 6242 ret = cmd_ops->set_filter(param, trigger_data, file); 6243 if (ret < 0) 6244 goto out_free; 6245 } 6246 6247 if (remove) { 6248 if (!have_hist_trigger_match(trigger_data, file)) 6249 goto out_free; 6250 6251 if (hist_trigger_check_refs(trigger_data, file)) { 6252 ret = -EBUSY; 6253 goto out_free; 6254 } 6255 6256 cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file); 6257 se_name = trace_event_name(file->event_call); 6258 se = find_synth_event(se_name); 6259 if (se) 6260 se->ref--; 6261 ret = 0; 6262 goto out_free; 6263 } 6264 6265 ret = cmd_ops->reg(glob, trigger_ops, trigger_data, file); 6266 /* 6267 * The above returns on success the # of triggers registered, 6268 * but if it didn't register any it returns zero. Consider no 6269 * triggers registered a failure too. 6270 */ 6271 if (!ret) { 6272 if (!(attrs->pause || attrs->cont || attrs->clear)) 6273 ret = -ENOENT; 6274 goto out_free; 6275 } else if (ret < 0) 6276 goto out_free; 6277 6278 if (get_named_trigger_data(trigger_data)) 6279 goto enable; 6280 6281 if (has_hist_vars(hist_data)) 6282 save_hist_vars(hist_data); 6283 6284 ret = create_actions(hist_data); 6285 if (ret) 6286 goto out_unreg; 6287 6288 ret = tracing_map_init(hist_data->map); 6289 if (ret) 6290 goto out_unreg; 6291 enable: 6292 ret = hist_trigger_enable(trigger_data, file); 6293 if (ret) 6294 goto out_unreg; 6295 6296 se_name = trace_event_name(file->event_call); 6297 se = find_synth_event(se_name); 6298 if (se) 6299 se->ref++; 6300 /* Just return zero, not the number of registered triggers */ 6301 ret = 0; 6302 out: 6303 if (ret == 0) 6304 hist_err_clear(); 6305 6306 return ret; 6307 out_unreg: 6308 cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file); 6309 out_free: 6310 if (cmd_ops->set_filter) 6311 cmd_ops->set_filter(NULL, trigger_data, NULL); 6312 6313 remove_hist_vars(hist_data); 6314 6315 kfree(trigger_data); 6316 6317 destroy_hist_data(hist_data); 6318 goto out; 6319 } 6320 6321 static struct event_command trigger_hist_cmd = { 6322 .name = "hist", 6323 .trigger_type = ETT_EVENT_HIST, 6324 .flags = EVENT_CMD_FL_NEEDS_REC, 6325 .func = event_hist_trigger_func, 6326 .reg = hist_register_trigger, 6327 .unreg = hist_unregister_trigger, 6328 .unreg_all = hist_unreg_all, 6329 .get_trigger_ops = event_hist_get_trigger_ops, 6330 .set_filter = set_trigger_filter, 6331 }; 6332 6333 __init int register_trigger_hist_cmd(void) 6334 { 6335 int ret; 6336 6337 ret = register_event_command(&trigger_hist_cmd); 6338 WARN_ON(ret < 0); 6339 6340 return ret; 6341 } 6342 6343 static void 6344 hist_enable_trigger(struct event_trigger_data *data, void *rec, 6345 struct ring_buffer_event *event) 6346 { 6347 struct enable_trigger_data *enable_data = data->private_data; 6348 struct event_trigger_data *test; 6349 6350 list_for_each_entry_rcu(test, &enable_data->file->triggers, list, 6351 lockdep_is_held(&event_mutex)) { 6352 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6353 if (enable_data->enable) 6354 test->paused = false; 6355 else 6356 test->paused = true; 6357 } 6358 } 6359 } 6360 6361 static void 6362 hist_enable_count_trigger(struct event_trigger_data *data, void *rec, 6363 struct ring_buffer_event *event) 6364 { 6365 if (!data->count) 6366 return; 6367 6368 if (data->count != -1) 6369 (data->count)--; 6370 6371 hist_enable_trigger(data, rec, event); 6372 } 6373 6374 static struct event_trigger_ops hist_enable_trigger_ops = { 6375 .func = hist_enable_trigger, 6376 .print = event_enable_trigger_print, 6377 .init = event_trigger_init, 6378 .free = event_enable_trigger_free, 6379 }; 6380 6381 static struct event_trigger_ops hist_enable_count_trigger_ops = { 6382 .func = hist_enable_count_trigger, 6383 .print = event_enable_trigger_print, 6384 .init = event_trigger_init, 6385 .free = event_enable_trigger_free, 6386 }; 6387 6388 static struct event_trigger_ops hist_disable_trigger_ops = { 6389 .func = hist_enable_trigger, 6390 .print = event_enable_trigger_print, 6391 .init = event_trigger_init, 6392 .free = event_enable_trigger_free, 6393 }; 6394 6395 static struct event_trigger_ops hist_disable_count_trigger_ops = { 6396 .func = hist_enable_count_trigger, 6397 .print = event_enable_trigger_print, 6398 .init = event_trigger_init, 6399 .free = event_enable_trigger_free, 6400 }; 6401 6402 static struct event_trigger_ops * 6403 hist_enable_get_trigger_ops(char *cmd, char *param) 6404 { 6405 struct event_trigger_ops *ops; 6406 bool enable; 6407 6408 enable = (strcmp(cmd, ENABLE_HIST_STR) == 0); 6409 6410 if (enable) 6411 ops = param ? &hist_enable_count_trigger_ops : 6412 &hist_enable_trigger_ops; 6413 else 6414 ops = param ? &hist_disable_count_trigger_ops : 6415 &hist_disable_trigger_ops; 6416 6417 return ops; 6418 } 6419 6420 static void hist_enable_unreg_all(struct trace_event_file *file) 6421 { 6422 struct event_trigger_data *test, *n; 6423 6424 list_for_each_entry_safe(test, n, &file->triggers, list) { 6425 if (test->cmd_ops->trigger_type == ETT_HIST_ENABLE) { 6426 list_del_rcu(&test->list); 6427 update_cond_flag(file); 6428 trace_event_trigger_enable_disable(file, 0); 6429 if (test->ops->free) 6430 test->ops->free(test->ops, test); 6431 } 6432 } 6433 } 6434 6435 static struct event_command trigger_hist_enable_cmd = { 6436 .name = ENABLE_HIST_STR, 6437 .trigger_type = ETT_HIST_ENABLE, 6438 .func = event_enable_trigger_func, 6439 .reg = event_enable_register_trigger, 6440 .unreg = event_enable_unregister_trigger, 6441 .unreg_all = hist_enable_unreg_all, 6442 .get_trigger_ops = hist_enable_get_trigger_ops, 6443 .set_filter = set_trigger_filter, 6444 }; 6445 6446 static struct event_command trigger_hist_disable_cmd = { 6447 .name = DISABLE_HIST_STR, 6448 .trigger_type = ETT_HIST_ENABLE, 6449 .func = event_enable_trigger_func, 6450 .reg = event_enable_register_trigger, 6451 .unreg = event_enable_unregister_trigger, 6452 .unreg_all = hist_enable_unreg_all, 6453 .get_trigger_ops = hist_enable_get_trigger_ops, 6454 .set_filter = set_trigger_filter, 6455 }; 6456 6457 static __init void unregister_trigger_hist_enable_disable_cmds(void) 6458 { 6459 unregister_event_command(&trigger_hist_enable_cmd); 6460 unregister_event_command(&trigger_hist_disable_cmd); 6461 } 6462 6463 __init int register_trigger_hist_enable_disable_cmds(void) 6464 { 6465 int ret; 6466 6467 ret = register_event_command(&trigger_hist_enable_cmd); 6468 if (WARN_ON(ret < 0)) 6469 return ret; 6470 ret = register_event_command(&trigger_hist_disable_cmd); 6471 if (WARN_ON(ret < 0)) 6472 unregister_trigger_hist_enable_disable_cmds(); 6473 6474 return ret; 6475 } 6476 6477 static __init int trace_events_hist_init(void) 6478 { 6479 struct dentry *entry = NULL; 6480 struct dentry *d_tracer; 6481 int err = 0; 6482 6483 err = dyn_event_register(&synth_event_ops); 6484 if (err) { 6485 pr_warn("Could not register synth_event_ops\n"); 6486 return err; 6487 } 6488 6489 d_tracer = tracing_init_dentry(); 6490 if (IS_ERR(d_tracer)) { 6491 err = PTR_ERR(d_tracer); 6492 goto err; 6493 } 6494 6495 entry = tracefs_create_file("synthetic_events", 0644, d_tracer, 6496 NULL, &synth_events_fops); 6497 if (!entry) { 6498 err = -ENODEV; 6499 goto err; 6500 } 6501 6502 return err; 6503 err: 6504 pr_warn("Could not create tracefs 'synthetic_events' entry\n"); 6505 6506 return err; 6507 } 6508 6509 fs_initcall(trace_events_hist_init); 6510