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 71 #undef C 72 #define C(a, b) HIST_ERR_##a 73 74 enum { ERRORS }; 75 76 #undef C 77 #define C(a, b) b 78 79 static const char *err_text[] = { ERRORS }; 80 81 struct hist_field; 82 83 typedef u64 (*hist_field_fn_t) (struct hist_field *field, 84 struct tracing_map_elt *elt, 85 struct ring_buffer_event *rbe, 86 void *event); 87 88 #define HIST_FIELD_OPERANDS_MAX 2 89 #define HIST_FIELDS_MAX (TRACING_MAP_FIELDS_MAX + TRACING_MAP_VARS_MAX) 90 #define HIST_ACTIONS_MAX 8 91 92 enum field_op_id { 93 FIELD_OP_NONE, 94 FIELD_OP_PLUS, 95 FIELD_OP_MINUS, 96 FIELD_OP_UNARY_MINUS, 97 }; 98 99 /* 100 * A hist_var (histogram variable) contains variable information for 101 * hist_fields having the HIST_FIELD_FL_VAR or HIST_FIELD_FL_VAR_REF 102 * flag set. A hist_var has a variable name e.g. ts0, and is 103 * associated with a given histogram trigger, as specified by 104 * hist_data. The hist_var idx is the unique index assigned to the 105 * variable by the hist trigger's tracing_map. The idx is what is 106 * used to set a variable's value and, by a variable reference, to 107 * retrieve it. 108 */ 109 struct hist_var { 110 char *name; 111 struct hist_trigger_data *hist_data; 112 unsigned int idx; 113 }; 114 115 struct hist_field { 116 struct ftrace_event_field *field; 117 unsigned long flags; 118 hist_field_fn_t fn; 119 unsigned int ref; 120 unsigned int size; 121 unsigned int offset; 122 unsigned int is_signed; 123 const char *type; 124 struct hist_field *operands[HIST_FIELD_OPERANDS_MAX]; 125 struct hist_trigger_data *hist_data; 126 127 /* 128 * Variable fields contain variable-specific info in var. 129 */ 130 struct hist_var var; 131 enum field_op_id operator; 132 char *system; 133 char *event_name; 134 135 /* 136 * The name field is used for EXPR and VAR_REF fields. VAR 137 * fields contain the variable name in var.name. 138 */ 139 char *name; 140 141 /* 142 * When a histogram trigger is hit, if it has any references 143 * to variables, the values of those variables are collected 144 * into a var_ref_vals array by resolve_var_refs(). The 145 * current value of each variable is read from the tracing_map 146 * using the hist field's hist_var.idx and entered into the 147 * var_ref_idx entry i.e. var_ref_vals[var_ref_idx]. 148 */ 149 unsigned int var_ref_idx; 150 bool read_once; 151 }; 152 153 static u64 hist_field_none(struct hist_field *field, 154 struct tracing_map_elt *elt, 155 struct ring_buffer_event *rbe, 156 void *event) 157 { 158 return 0; 159 } 160 161 static u64 hist_field_counter(struct hist_field *field, 162 struct tracing_map_elt *elt, 163 struct ring_buffer_event *rbe, 164 void *event) 165 { 166 return 1; 167 } 168 169 static u64 hist_field_string(struct hist_field *hist_field, 170 struct tracing_map_elt *elt, 171 struct ring_buffer_event *rbe, 172 void *event) 173 { 174 char *addr = (char *)(event + hist_field->field->offset); 175 176 return (u64)(unsigned long)addr; 177 } 178 179 static u64 hist_field_dynstring(struct hist_field *hist_field, 180 struct tracing_map_elt *elt, 181 struct ring_buffer_event *rbe, 182 void *event) 183 { 184 u32 str_item = *(u32 *)(event + hist_field->field->offset); 185 int str_loc = str_item & 0xffff; 186 char *addr = (char *)(event + str_loc); 187 188 return (u64)(unsigned long)addr; 189 } 190 191 static u64 hist_field_pstring(struct hist_field *hist_field, 192 struct tracing_map_elt *elt, 193 struct ring_buffer_event *rbe, 194 void *event) 195 { 196 char **addr = (char **)(event + hist_field->field->offset); 197 198 return (u64)(unsigned long)*addr; 199 } 200 201 static u64 hist_field_log2(struct hist_field *hist_field, 202 struct tracing_map_elt *elt, 203 struct ring_buffer_event *rbe, 204 void *event) 205 { 206 struct hist_field *operand = hist_field->operands[0]; 207 208 u64 val = operand->fn(operand, elt, rbe, event); 209 210 return (u64) ilog2(roundup_pow_of_two(val)); 211 } 212 213 static u64 hist_field_plus(struct hist_field *hist_field, 214 struct tracing_map_elt *elt, 215 struct ring_buffer_event *rbe, 216 void *event) 217 { 218 struct hist_field *operand1 = hist_field->operands[0]; 219 struct hist_field *operand2 = hist_field->operands[1]; 220 221 u64 val1 = operand1->fn(operand1, elt, rbe, event); 222 u64 val2 = operand2->fn(operand2, elt, rbe, event); 223 224 return val1 + val2; 225 } 226 227 static u64 hist_field_minus(struct hist_field *hist_field, 228 struct tracing_map_elt *elt, 229 struct ring_buffer_event *rbe, 230 void *event) 231 { 232 struct hist_field *operand1 = hist_field->operands[0]; 233 struct hist_field *operand2 = hist_field->operands[1]; 234 235 u64 val1 = operand1->fn(operand1, elt, rbe, event); 236 u64 val2 = operand2->fn(operand2, elt, rbe, event); 237 238 return val1 - val2; 239 } 240 241 static u64 hist_field_unary_minus(struct hist_field *hist_field, 242 struct tracing_map_elt *elt, 243 struct ring_buffer_event *rbe, 244 void *event) 245 { 246 struct hist_field *operand = hist_field->operands[0]; 247 248 s64 sval = (s64)operand->fn(operand, elt, rbe, event); 249 u64 val = (u64)-sval; 250 251 return val; 252 } 253 254 #define DEFINE_HIST_FIELD_FN(type) \ 255 static u64 hist_field_##type(struct hist_field *hist_field, \ 256 struct tracing_map_elt *elt, \ 257 struct ring_buffer_event *rbe, \ 258 void *event) \ 259 { \ 260 type *addr = (type *)(event + hist_field->field->offset); \ 261 \ 262 return (u64)(unsigned long)*addr; \ 263 } 264 265 DEFINE_HIST_FIELD_FN(s64); 266 DEFINE_HIST_FIELD_FN(u64); 267 DEFINE_HIST_FIELD_FN(s32); 268 DEFINE_HIST_FIELD_FN(u32); 269 DEFINE_HIST_FIELD_FN(s16); 270 DEFINE_HIST_FIELD_FN(u16); 271 DEFINE_HIST_FIELD_FN(s8); 272 DEFINE_HIST_FIELD_FN(u8); 273 274 #define for_each_hist_field(i, hist_data) \ 275 for ((i) = 0; (i) < (hist_data)->n_fields; (i)++) 276 277 #define for_each_hist_val_field(i, hist_data) \ 278 for ((i) = 0; (i) < (hist_data)->n_vals; (i)++) 279 280 #define for_each_hist_key_field(i, hist_data) \ 281 for ((i) = (hist_data)->n_vals; (i) < (hist_data)->n_fields; (i)++) 282 283 #define HIST_STACKTRACE_DEPTH 16 284 #define HIST_STACKTRACE_SIZE (HIST_STACKTRACE_DEPTH * sizeof(unsigned long)) 285 #define HIST_STACKTRACE_SKIP 5 286 287 #define HITCOUNT_IDX 0 288 #define HIST_KEY_SIZE_MAX (MAX_FILTER_STR_VAL + HIST_STACKTRACE_SIZE) 289 290 enum hist_field_flags { 291 HIST_FIELD_FL_HITCOUNT = 1 << 0, 292 HIST_FIELD_FL_KEY = 1 << 1, 293 HIST_FIELD_FL_STRING = 1 << 2, 294 HIST_FIELD_FL_HEX = 1 << 3, 295 HIST_FIELD_FL_SYM = 1 << 4, 296 HIST_FIELD_FL_SYM_OFFSET = 1 << 5, 297 HIST_FIELD_FL_EXECNAME = 1 << 6, 298 HIST_FIELD_FL_SYSCALL = 1 << 7, 299 HIST_FIELD_FL_STACKTRACE = 1 << 8, 300 HIST_FIELD_FL_LOG2 = 1 << 9, 301 HIST_FIELD_FL_TIMESTAMP = 1 << 10, 302 HIST_FIELD_FL_TIMESTAMP_USECS = 1 << 11, 303 HIST_FIELD_FL_VAR = 1 << 12, 304 HIST_FIELD_FL_EXPR = 1 << 13, 305 HIST_FIELD_FL_VAR_REF = 1 << 14, 306 HIST_FIELD_FL_CPU = 1 << 15, 307 HIST_FIELD_FL_ALIAS = 1 << 16, 308 }; 309 310 struct var_defs { 311 unsigned int n_vars; 312 char *name[TRACING_MAP_VARS_MAX]; 313 char *expr[TRACING_MAP_VARS_MAX]; 314 }; 315 316 struct hist_trigger_attrs { 317 char *keys_str; 318 char *vals_str; 319 char *sort_key_str; 320 char *name; 321 char *clock; 322 bool pause; 323 bool cont; 324 bool clear; 325 bool ts_in_usecs; 326 unsigned int map_bits; 327 328 char *assignment_str[TRACING_MAP_VARS_MAX]; 329 unsigned int n_assignments; 330 331 char *action_str[HIST_ACTIONS_MAX]; 332 unsigned int n_actions; 333 334 struct var_defs var_defs; 335 }; 336 337 struct field_var { 338 struct hist_field *var; 339 struct hist_field *val; 340 }; 341 342 struct field_var_hist { 343 struct hist_trigger_data *hist_data; 344 char *cmd; 345 }; 346 347 struct hist_trigger_data { 348 struct hist_field *fields[HIST_FIELDS_MAX]; 349 unsigned int n_vals; 350 unsigned int n_keys; 351 unsigned int n_fields; 352 unsigned int n_vars; 353 unsigned int key_size; 354 struct tracing_map_sort_key sort_keys[TRACING_MAP_SORT_KEYS_MAX]; 355 unsigned int n_sort_keys; 356 struct trace_event_file *event_file; 357 struct hist_trigger_attrs *attrs; 358 struct tracing_map *map; 359 bool enable_timestamps; 360 bool remove; 361 struct hist_field *var_refs[TRACING_MAP_VARS_MAX]; 362 unsigned int n_var_refs; 363 364 struct action_data *actions[HIST_ACTIONS_MAX]; 365 unsigned int n_actions; 366 367 struct field_var *field_vars[SYNTH_FIELDS_MAX]; 368 unsigned int n_field_vars; 369 unsigned int n_field_var_str; 370 struct field_var_hist *field_var_hists[SYNTH_FIELDS_MAX]; 371 unsigned int n_field_var_hists; 372 373 struct field_var *save_vars[SYNTH_FIELDS_MAX]; 374 unsigned int n_save_vars; 375 unsigned int n_save_var_str; 376 }; 377 378 static int synth_event_create(int argc, const char **argv); 379 static int synth_event_show(struct seq_file *m, struct dyn_event *ev); 380 static int synth_event_release(struct dyn_event *ev); 381 static bool synth_event_is_busy(struct dyn_event *ev); 382 static bool synth_event_match(const char *system, const char *event, 383 int argc, const char **argv, struct dyn_event *ev); 384 385 static struct dyn_event_operations synth_event_ops = { 386 .create = synth_event_create, 387 .show = synth_event_show, 388 .is_busy = synth_event_is_busy, 389 .free = synth_event_release, 390 .match = synth_event_match, 391 }; 392 393 struct synth_field { 394 char *type; 395 char *name; 396 size_t size; 397 bool is_signed; 398 bool is_string; 399 }; 400 401 struct synth_event { 402 struct dyn_event devent; 403 int ref; 404 char *name; 405 struct synth_field **fields; 406 unsigned int n_fields; 407 unsigned int n_u64; 408 struct trace_event_class class; 409 struct trace_event_call call; 410 struct tracepoint *tp; 411 }; 412 413 static bool is_synth_event(struct dyn_event *ev) 414 { 415 return ev->ops == &synth_event_ops; 416 } 417 418 static struct synth_event *to_synth_event(struct dyn_event *ev) 419 { 420 return container_of(ev, struct synth_event, devent); 421 } 422 423 static bool synth_event_is_busy(struct dyn_event *ev) 424 { 425 struct synth_event *event = to_synth_event(ev); 426 427 return event->ref != 0; 428 } 429 430 static bool synth_event_match(const char *system, const char *event, 431 int argc, const char **argv, struct dyn_event *ev) 432 { 433 struct synth_event *sev = to_synth_event(ev); 434 435 return strcmp(sev->name, event) == 0 && 436 (!system || strcmp(system, SYNTH_SYSTEM) == 0); 437 } 438 439 struct action_data; 440 441 typedef void (*action_fn_t) (struct hist_trigger_data *hist_data, 442 struct tracing_map_elt *elt, void *rec, 443 struct ring_buffer_event *rbe, void *key, 444 struct action_data *data, u64 *var_ref_vals); 445 446 typedef bool (*check_track_val_fn_t) (u64 track_val, u64 var_val); 447 448 enum handler_id { 449 HANDLER_ONMATCH = 1, 450 HANDLER_ONMAX, 451 HANDLER_ONCHANGE, 452 }; 453 454 enum action_id { 455 ACTION_SAVE = 1, 456 ACTION_TRACE, 457 ACTION_SNAPSHOT, 458 }; 459 460 struct action_data { 461 enum handler_id handler; 462 enum action_id action; 463 char *action_name; 464 action_fn_t fn; 465 466 unsigned int n_params; 467 char *params[SYNTH_FIELDS_MAX]; 468 469 /* 470 * When a histogram trigger is hit, the values of any 471 * references to variables, including variables being passed 472 * as parameters to synthetic events, are collected into a 473 * var_ref_vals array. This var_ref_idx is the index of the 474 * first param in the array to be passed to the synthetic 475 * event invocation. 476 */ 477 unsigned int var_ref_idx; 478 struct synth_event *synth_event; 479 bool use_trace_keyword; 480 char *synth_event_name; 481 482 union { 483 struct { 484 char *event; 485 char *event_system; 486 } match_data; 487 488 struct { 489 /* 490 * var_str contains the $-unstripped variable 491 * name referenced by var_ref, and used when 492 * printing the action. Because var_ref 493 * creation is deferred to create_actions(), 494 * we need a per-action way to save it until 495 * then, thus var_str. 496 */ 497 char *var_str; 498 499 /* 500 * var_ref refers to the variable being 501 * tracked e.g onmax($var). 502 */ 503 struct hist_field *var_ref; 504 505 /* 506 * track_var contains the 'invisible' tracking 507 * variable created to keep the current 508 * e.g. max value. 509 */ 510 struct hist_field *track_var; 511 512 check_track_val_fn_t check_val; 513 action_fn_t save_data; 514 } track_data; 515 }; 516 }; 517 518 struct track_data { 519 u64 track_val; 520 bool updated; 521 522 unsigned int key_len; 523 void *key; 524 struct tracing_map_elt elt; 525 526 struct action_data *action_data; 527 struct hist_trigger_data *hist_data; 528 }; 529 530 struct hist_elt_data { 531 char *comm; 532 u64 *var_ref_vals; 533 char *field_var_str[SYNTH_FIELDS_MAX]; 534 }; 535 536 struct snapshot_context { 537 struct tracing_map_elt *elt; 538 void *key; 539 }; 540 541 static void track_data_free(struct track_data *track_data) 542 { 543 struct hist_elt_data *elt_data; 544 545 if (!track_data) 546 return; 547 548 kfree(track_data->key); 549 550 elt_data = track_data->elt.private_data; 551 if (elt_data) { 552 kfree(elt_data->comm); 553 kfree(elt_data); 554 } 555 556 kfree(track_data); 557 } 558 559 static struct track_data *track_data_alloc(unsigned int key_len, 560 struct action_data *action_data, 561 struct hist_trigger_data *hist_data) 562 { 563 struct track_data *data = kzalloc(sizeof(*data), GFP_KERNEL); 564 struct hist_elt_data *elt_data; 565 566 if (!data) 567 return ERR_PTR(-ENOMEM); 568 569 data->key = kzalloc(key_len, GFP_KERNEL); 570 if (!data->key) { 571 track_data_free(data); 572 return ERR_PTR(-ENOMEM); 573 } 574 575 data->key_len = key_len; 576 data->action_data = action_data; 577 data->hist_data = hist_data; 578 579 elt_data = kzalloc(sizeof(*elt_data), GFP_KERNEL); 580 if (!elt_data) { 581 track_data_free(data); 582 return ERR_PTR(-ENOMEM); 583 } 584 data->elt.private_data = elt_data; 585 586 elt_data->comm = kzalloc(TASK_COMM_LEN, GFP_KERNEL); 587 if (!elt_data->comm) { 588 track_data_free(data); 589 return ERR_PTR(-ENOMEM); 590 } 591 592 return data; 593 } 594 595 static char last_cmd[MAX_FILTER_STR_VAL]; 596 static char last_cmd_loc[MAX_FILTER_STR_VAL]; 597 598 static int errpos(char *str) 599 { 600 return err_pos(last_cmd, str); 601 } 602 603 static void last_cmd_set(struct trace_event_file *file, char *str) 604 { 605 const char *system = NULL, *name = NULL; 606 struct trace_event_call *call; 607 608 if (!str) 609 return; 610 611 strncpy(last_cmd, str, MAX_FILTER_STR_VAL - 1); 612 613 if (file) { 614 call = file->event_call; 615 616 system = call->class->system; 617 if (system) { 618 name = trace_event_name(call); 619 if (!name) 620 system = NULL; 621 } 622 } 623 624 if (system) 625 snprintf(last_cmd_loc, MAX_FILTER_STR_VAL, "hist:%s:%s", system, name); 626 } 627 628 static void hist_err(struct trace_array *tr, u8 err_type, u8 err_pos) 629 { 630 tracing_log_err(tr, last_cmd_loc, last_cmd, err_text, 631 err_type, err_pos); 632 } 633 634 static void hist_err_clear(void) 635 { 636 last_cmd[0] = '\0'; 637 last_cmd_loc[0] = '\0'; 638 } 639 640 struct synth_trace_event { 641 struct trace_entry ent; 642 u64 fields[]; 643 }; 644 645 static int synth_event_define_fields(struct trace_event_call *call) 646 { 647 struct synth_trace_event trace; 648 int offset = offsetof(typeof(trace), fields); 649 struct synth_event *event = call->data; 650 unsigned int i, size, n_u64; 651 char *name, *type; 652 bool is_signed; 653 int ret = 0; 654 655 for (i = 0, n_u64 = 0; i < event->n_fields; i++) { 656 size = event->fields[i]->size; 657 is_signed = event->fields[i]->is_signed; 658 type = event->fields[i]->type; 659 name = event->fields[i]->name; 660 ret = trace_define_field(call, type, name, offset, size, 661 is_signed, FILTER_OTHER); 662 if (ret) 663 break; 664 665 if (event->fields[i]->is_string) { 666 offset += STR_VAR_LEN_MAX; 667 n_u64 += STR_VAR_LEN_MAX / sizeof(u64); 668 } else { 669 offset += sizeof(u64); 670 n_u64++; 671 } 672 } 673 674 event->n_u64 = n_u64; 675 676 return ret; 677 } 678 679 static bool synth_field_signed(char *type) 680 { 681 if (str_has_prefix(type, "u")) 682 return false; 683 if (strcmp(type, "gfp_t") == 0) 684 return false; 685 686 return true; 687 } 688 689 static int synth_field_is_string(char *type) 690 { 691 if (strstr(type, "char[") != NULL) 692 return true; 693 694 return false; 695 } 696 697 static int synth_field_string_size(char *type) 698 { 699 char buf[4], *end, *start; 700 unsigned int len; 701 int size, err; 702 703 start = strstr(type, "char["); 704 if (start == NULL) 705 return -EINVAL; 706 start += sizeof("char[") - 1; 707 708 end = strchr(type, ']'); 709 if (!end || end < start) 710 return -EINVAL; 711 712 len = end - start; 713 if (len > 3) 714 return -EINVAL; 715 716 strncpy(buf, start, len); 717 buf[len] = '\0'; 718 719 err = kstrtouint(buf, 0, &size); 720 if (err) 721 return err; 722 723 if (size > STR_VAR_LEN_MAX) 724 return -EINVAL; 725 726 return size; 727 } 728 729 static int synth_field_size(char *type) 730 { 731 int size = 0; 732 733 if (strcmp(type, "s64") == 0) 734 size = sizeof(s64); 735 else if (strcmp(type, "u64") == 0) 736 size = sizeof(u64); 737 else if (strcmp(type, "s32") == 0) 738 size = sizeof(s32); 739 else if (strcmp(type, "u32") == 0) 740 size = sizeof(u32); 741 else if (strcmp(type, "s16") == 0) 742 size = sizeof(s16); 743 else if (strcmp(type, "u16") == 0) 744 size = sizeof(u16); 745 else if (strcmp(type, "s8") == 0) 746 size = sizeof(s8); 747 else if (strcmp(type, "u8") == 0) 748 size = sizeof(u8); 749 else if (strcmp(type, "char") == 0) 750 size = sizeof(char); 751 else if (strcmp(type, "unsigned char") == 0) 752 size = sizeof(unsigned char); 753 else if (strcmp(type, "int") == 0) 754 size = sizeof(int); 755 else if (strcmp(type, "unsigned int") == 0) 756 size = sizeof(unsigned int); 757 else if (strcmp(type, "long") == 0) 758 size = sizeof(long); 759 else if (strcmp(type, "unsigned long") == 0) 760 size = sizeof(unsigned long); 761 else if (strcmp(type, "pid_t") == 0) 762 size = sizeof(pid_t); 763 else if (strcmp(type, "gfp_t") == 0) 764 size = sizeof(gfp_t); 765 else if (synth_field_is_string(type)) 766 size = synth_field_string_size(type); 767 768 return size; 769 } 770 771 static const char *synth_field_fmt(char *type) 772 { 773 const char *fmt = "%llu"; 774 775 if (strcmp(type, "s64") == 0) 776 fmt = "%lld"; 777 else if (strcmp(type, "u64") == 0) 778 fmt = "%llu"; 779 else if (strcmp(type, "s32") == 0) 780 fmt = "%d"; 781 else if (strcmp(type, "u32") == 0) 782 fmt = "%u"; 783 else if (strcmp(type, "s16") == 0) 784 fmt = "%d"; 785 else if (strcmp(type, "u16") == 0) 786 fmt = "%u"; 787 else if (strcmp(type, "s8") == 0) 788 fmt = "%d"; 789 else if (strcmp(type, "u8") == 0) 790 fmt = "%u"; 791 else if (strcmp(type, "char") == 0) 792 fmt = "%d"; 793 else if (strcmp(type, "unsigned char") == 0) 794 fmt = "%u"; 795 else if (strcmp(type, "int") == 0) 796 fmt = "%d"; 797 else if (strcmp(type, "unsigned int") == 0) 798 fmt = "%u"; 799 else if (strcmp(type, "long") == 0) 800 fmt = "%ld"; 801 else if (strcmp(type, "unsigned long") == 0) 802 fmt = "%lu"; 803 else if (strcmp(type, "pid_t") == 0) 804 fmt = "%d"; 805 else if (strcmp(type, "gfp_t") == 0) 806 fmt = "%x"; 807 else if (synth_field_is_string(type)) 808 fmt = "%s"; 809 810 return fmt; 811 } 812 813 static enum print_line_t print_synth_event(struct trace_iterator *iter, 814 int flags, 815 struct trace_event *event) 816 { 817 struct trace_array *tr = iter->tr; 818 struct trace_seq *s = &iter->seq; 819 struct synth_trace_event *entry; 820 struct synth_event *se; 821 unsigned int i, n_u64; 822 char print_fmt[32]; 823 const char *fmt; 824 825 entry = (struct synth_trace_event *)iter->ent; 826 se = container_of(event, struct synth_event, call.event); 827 828 trace_seq_printf(s, "%s: ", se->name); 829 830 for (i = 0, n_u64 = 0; i < se->n_fields; i++) { 831 if (trace_seq_has_overflowed(s)) 832 goto end; 833 834 fmt = synth_field_fmt(se->fields[i]->type); 835 836 /* parameter types */ 837 if (tr->trace_flags & TRACE_ITER_VERBOSE) 838 trace_seq_printf(s, "%s ", fmt); 839 840 snprintf(print_fmt, sizeof(print_fmt), "%%s=%s%%s", fmt); 841 842 /* parameter values */ 843 if (se->fields[i]->is_string) { 844 trace_seq_printf(s, print_fmt, se->fields[i]->name, 845 (char *)&entry->fields[n_u64], 846 i == se->n_fields - 1 ? "" : " "); 847 n_u64 += STR_VAR_LEN_MAX / sizeof(u64); 848 } else { 849 struct trace_print_flags __flags[] = { 850 __def_gfpflag_names, {-1, NULL} }; 851 852 trace_seq_printf(s, print_fmt, se->fields[i]->name, 853 entry->fields[n_u64], 854 i == se->n_fields - 1 ? "" : " "); 855 856 if (strcmp(se->fields[i]->type, "gfp_t") == 0) { 857 trace_seq_puts(s, " ("); 858 trace_print_flags_seq(s, "|", 859 entry->fields[n_u64], 860 __flags); 861 trace_seq_putc(s, ')'); 862 } 863 n_u64++; 864 } 865 } 866 end: 867 trace_seq_putc(s, '\n'); 868 869 return trace_handle_return(s); 870 } 871 872 static struct trace_event_functions synth_event_funcs = { 873 .trace = print_synth_event 874 }; 875 876 static notrace void trace_event_raw_event_synth(void *__data, 877 u64 *var_ref_vals, 878 unsigned int var_ref_idx) 879 { 880 struct trace_event_file *trace_file = __data; 881 struct synth_trace_event *entry; 882 struct trace_event_buffer fbuffer; 883 struct ring_buffer *buffer; 884 struct synth_event *event; 885 unsigned int i, n_u64; 886 int fields_size = 0; 887 888 event = trace_file->event_call->data; 889 890 if (trace_trigger_soft_disabled(trace_file)) 891 return; 892 893 fields_size = event->n_u64 * sizeof(u64); 894 895 /* 896 * Avoid ring buffer recursion detection, as this event 897 * is being performed within another event. 898 */ 899 buffer = trace_file->tr->trace_buffer.buffer; 900 ring_buffer_nest_start(buffer); 901 902 entry = trace_event_buffer_reserve(&fbuffer, trace_file, 903 sizeof(*entry) + fields_size); 904 if (!entry) 905 goto out; 906 907 for (i = 0, n_u64 = 0; i < event->n_fields; i++) { 908 if (event->fields[i]->is_string) { 909 char *str_val = (char *)(long)var_ref_vals[var_ref_idx + i]; 910 char *str_field = (char *)&entry->fields[n_u64]; 911 912 strscpy(str_field, str_val, STR_VAR_LEN_MAX); 913 n_u64 += STR_VAR_LEN_MAX / sizeof(u64); 914 } else { 915 struct synth_field *field = event->fields[i]; 916 u64 val = var_ref_vals[var_ref_idx + i]; 917 918 switch (field->size) { 919 case 1: 920 *(u8 *)&entry->fields[n_u64] = (u8)val; 921 break; 922 923 case 2: 924 *(u16 *)&entry->fields[n_u64] = (u16)val; 925 break; 926 927 case 4: 928 *(u32 *)&entry->fields[n_u64] = (u32)val; 929 break; 930 931 default: 932 entry->fields[n_u64] = val; 933 break; 934 } 935 n_u64++; 936 } 937 } 938 939 trace_event_buffer_commit(&fbuffer); 940 out: 941 ring_buffer_nest_end(buffer); 942 } 943 944 static void free_synth_event_print_fmt(struct trace_event_call *call) 945 { 946 if (call) { 947 kfree(call->print_fmt); 948 call->print_fmt = NULL; 949 } 950 } 951 952 static int __set_synth_event_print_fmt(struct synth_event *event, 953 char *buf, int len) 954 { 955 const char *fmt; 956 int pos = 0; 957 int i; 958 959 /* When len=0, we just calculate the needed length */ 960 #define LEN_OR_ZERO (len ? len - pos : 0) 961 962 pos += snprintf(buf + pos, LEN_OR_ZERO, "\""); 963 for (i = 0; i < event->n_fields; i++) { 964 fmt = synth_field_fmt(event->fields[i]->type); 965 pos += snprintf(buf + pos, LEN_OR_ZERO, "%s=%s%s", 966 event->fields[i]->name, fmt, 967 i == event->n_fields - 1 ? "" : ", "); 968 } 969 pos += snprintf(buf + pos, LEN_OR_ZERO, "\""); 970 971 for (i = 0; i < event->n_fields; i++) { 972 pos += snprintf(buf + pos, LEN_OR_ZERO, 973 ", REC->%s", event->fields[i]->name); 974 } 975 976 #undef LEN_OR_ZERO 977 978 /* return the length of print_fmt */ 979 return pos; 980 } 981 982 static int set_synth_event_print_fmt(struct trace_event_call *call) 983 { 984 struct synth_event *event = call->data; 985 char *print_fmt; 986 int len; 987 988 /* First: called with 0 length to calculate the needed length */ 989 len = __set_synth_event_print_fmt(event, NULL, 0); 990 991 print_fmt = kmalloc(len + 1, GFP_KERNEL); 992 if (!print_fmt) 993 return -ENOMEM; 994 995 /* Second: actually write the @print_fmt */ 996 __set_synth_event_print_fmt(event, print_fmt, len + 1); 997 call->print_fmt = print_fmt; 998 999 return 0; 1000 } 1001 1002 static void free_synth_field(struct synth_field *field) 1003 { 1004 kfree(field->type); 1005 kfree(field->name); 1006 kfree(field); 1007 } 1008 1009 static struct synth_field *parse_synth_field(int argc, const char **argv, 1010 int *consumed) 1011 { 1012 struct synth_field *field; 1013 const char *prefix = NULL, *field_type = argv[0], *field_name, *array; 1014 int len, ret = 0; 1015 1016 if (field_type[0] == ';') 1017 field_type++; 1018 1019 if (!strcmp(field_type, "unsigned")) { 1020 if (argc < 3) 1021 return ERR_PTR(-EINVAL); 1022 prefix = "unsigned "; 1023 field_type = argv[1]; 1024 field_name = argv[2]; 1025 *consumed = 3; 1026 } else { 1027 field_name = argv[1]; 1028 *consumed = 2; 1029 } 1030 1031 field = kzalloc(sizeof(*field), GFP_KERNEL); 1032 if (!field) 1033 return ERR_PTR(-ENOMEM); 1034 1035 len = strlen(field_name); 1036 array = strchr(field_name, '['); 1037 if (array) 1038 len -= strlen(array); 1039 else if (field_name[len - 1] == ';') 1040 len--; 1041 1042 field->name = kmemdup_nul(field_name, len, GFP_KERNEL); 1043 if (!field->name) { 1044 ret = -ENOMEM; 1045 goto free; 1046 } 1047 1048 if (field_type[0] == ';') 1049 field_type++; 1050 len = strlen(field_type) + 1; 1051 if (array) 1052 len += strlen(array); 1053 if (prefix) 1054 len += strlen(prefix); 1055 1056 field->type = kzalloc(len, GFP_KERNEL); 1057 if (!field->type) { 1058 ret = -ENOMEM; 1059 goto free; 1060 } 1061 if (prefix) 1062 strcat(field->type, prefix); 1063 strcat(field->type, field_type); 1064 if (array) { 1065 strcat(field->type, array); 1066 if (field->type[len - 1] == ';') 1067 field->type[len - 1] = '\0'; 1068 } 1069 1070 field->size = synth_field_size(field->type); 1071 if (!field->size) { 1072 ret = -EINVAL; 1073 goto free; 1074 } 1075 1076 if (synth_field_is_string(field->type)) 1077 field->is_string = true; 1078 1079 field->is_signed = synth_field_signed(field->type); 1080 1081 out: 1082 return field; 1083 free: 1084 free_synth_field(field); 1085 field = ERR_PTR(ret); 1086 goto out; 1087 } 1088 1089 static void free_synth_tracepoint(struct tracepoint *tp) 1090 { 1091 if (!tp) 1092 return; 1093 1094 kfree(tp->name); 1095 kfree(tp); 1096 } 1097 1098 static struct tracepoint *alloc_synth_tracepoint(char *name) 1099 { 1100 struct tracepoint *tp; 1101 1102 tp = kzalloc(sizeof(*tp), GFP_KERNEL); 1103 if (!tp) 1104 return ERR_PTR(-ENOMEM); 1105 1106 tp->name = kstrdup(name, GFP_KERNEL); 1107 if (!tp->name) { 1108 kfree(tp); 1109 return ERR_PTR(-ENOMEM); 1110 } 1111 1112 return tp; 1113 } 1114 1115 typedef void (*synth_probe_func_t) (void *__data, u64 *var_ref_vals, 1116 unsigned int var_ref_idx); 1117 1118 static inline void trace_synth(struct synth_event *event, u64 *var_ref_vals, 1119 unsigned int var_ref_idx) 1120 { 1121 struct tracepoint *tp = event->tp; 1122 1123 if (unlikely(atomic_read(&tp->key.enabled) > 0)) { 1124 struct tracepoint_func *probe_func_ptr; 1125 synth_probe_func_t probe_func; 1126 void *__data; 1127 1128 if (!(cpu_online(raw_smp_processor_id()))) 1129 return; 1130 1131 probe_func_ptr = rcu_dereference_sched((tp)->funcs); 1132 if (probe_func_ptr) { 1133 do { 1134 probe_func = probe_func_ptr->func; 1135 __data = probe_func_ptr->data; 1136 probe_func(__data, var_ref_vals, var_ref_idx); 1137 } while ((++probe_func_ptr)->func); 1138 } 1139 } 1140 } 1141 1142 static struct synth_event *find_synth_event(const char *name) 1143 { 1144 struct dyn_event *pos; 1145 struct synth_event *event; 1146 1147 for_each_dyn_event(pos) { 1148 if (!is_synth_event(pos)) 1149 continue; 1150 event = to_synth_event(pos); 1151 if (strcmp(event->name, name) == 0) 1152 return event; 1153 } 1154 1155 return NULL; 1156 } 1157 1158 static int register_synth_event(struct synth_event *event) 1159 { 1160 struct trace_event_call *call = &event->call; 1161 int ret = 0; 1162 1163 event->call.class = &event->class; 1164 event->class.system = kstrdup(SYNTH_SYSTEM, GFP_KERNEL); 1165 if (!event->class.system) { 1166 ret = -ENOMEM; 1167 goto out; 1168 } 1169 1170 event->tp = alloc_synth_tracepoint(event->name); 1171 if (IS_ERR(event->tp)) { 1172 ret = PTR_ERR(event->tp); 1173 event->tp = NULL; 1174 goto out; 1175 } 1176 1177 INIT_LIST_HEAD(&call->class->fields); 1178 call->event.funcs = &synth_event_funcs; 1179 call->class->define_fields = synth_event_define_fields; 1180 1181 ret = register_trace_event(&call->event); 1182 if (!ret) { 1183 ret = -ENODEV; 1184 goto out; 1185 } 1186 call->flags = TRACE_EVENT_FL_TRACEPOINT; 1187 call->class->reg = trace_event_reg; 1188 call->class->probe = trace_event_raw_event_synth; 1189 call->data = event; 1190 call->tp = event->tp; 1191 1192 ret = trace_add_event_call(call); 1193 if (ret) { 1194 pr_warn("Failed to register synthetic event: %s\n", 1195 trace_event_name(call)); 1196 goto err; 1197 } 1198 1199 ret = set_synth_event_print_fmt(call); 1200 if (ret < 0) { 1201 trace_remove_event_call(call); 1202 goto err; 1203 } 1204 out: 1205 return ret; 1206 err: 1207 unregister_trace_event(&call->event); 1208 goto out; 1209 } 1210 1211 static int unregister_synth_event(struct synth_event *event) 1212 { 1213 struct trace_event_call *call = &event->call; 1214 int ret; 1215 1216 ret = trace_remove_event_call(call); 1217 1218 return ret; 1219 } 1220 1221 static void free_synth_event(struct synth_event *event) 1222 { 1223 unsigned int i; 1224 1225 if (!event) 1226 return; 1227 1228 for (i = 0; i < event->n_fields; i++) 1229 free_synth_field(event->fields[i]); 1230 1231 kfree(event->fields); 1232 kfree(event->name); 1233 kfree(event->class.system); 1234 free_synth_tracepoint(event->tp); 1235 free_synth_event_print_fmt(&event->call); 1236 kfree(event); 1237 } 1238 1239 static struct synth_event *alloc_synth_event(const char *name, int n_fields, 1240 struct synth_field **fields) 1241 { 1242 struct synth_event *event; 1243 unsigned int i; 1244 1245 event = kzalloc(sizeof(*event), GFP_KERNEL); 1246 if (!event) { 1247 event = ERR_PTR(-ENOMEM); 1248 goto out; 1249 } 1250 1251 event->name = kstrdup(name, GFP_KERNEL); 1252 if (!event->name) { 1253 kfree(event); 1254 event = ERR_PTR(-ENOMEM); 1255 goto out; 1256 } 1257 1258 event->fields = kcalloc(n_fields, sizeof(*event->fields), GFP_KERNEL); 1259 if (!event->fields) { 1260 free_synth_event(event); 1261 event = ERR_PTR(-ENOMEM); 1262 goto out; 1263 } 1264 1265 dyn_event_init(&event->devent, &synth_event_ops); 1266 1267 for (i = 0; i < n_fields; i++) 1268 event->fields[i] = fields[i]; 1269 1270 event->n_fields = n_fields; 1271 out: 1272 return event; 1273 } 1274 1275 static void action_trace(struct hist_trigger_data *hist_data, 1276 struct tracing_map_elt *elt, void *rec, 1277 struct ring_buffer_event *rbe, void *key, 1278 struct action_data *data, u64 *var_ref_vals) 1279 { 1280 struct synth_event *event = data->synth_event; 1281 1282 trace_synth(event, var_ref_vals, data->var_ref_idx); 1283 } 1284 1285 struct hist_var_data { 1286 struct list_head list; 1287 struct hist_trigger_data *hist_data; 1288 }; 1289 1290 static int __create_synth_event(int argc, const char *name, const char **argv) 1291 { 1292 struct synth_field *field, *fields[SYNTH_FIELDS_MAX]; 1293 struct synth_event *event = NULL; 1294 int i, consumed = 0, n_fields = 0, ret = 0; 1295 1296 /* 1297 * Argument syntax: 1298 * - Add synthetic event: <event_name> field[;field] ... 1299 * - Remove synthetic event: !<event_name> field[;field] ... 1300 * where 'field' = type field_name 1301 */ 1302 1303 if (name[0] == '\0' || argc < 1) 1304 return -EINVAL; 1305 1306 mutex_lock(&event_mutex); 1307 1308 event = find_synth_event(name); 1309 if (event) { 1310 ret = -EEXIST; 1311 goto out; 1312 } 1313 1314 for (i = 0; i < argc - 1; i++) { 1315 if (strcmp(argv[i], ";") == 0) 1316 continue; 1317 if (n_fields == SYNTH_FIELDS_MAX) { 1318 ret = -EINVAL; 1319 goto err; 1320 } 1321 1322 field = parse_synth_field(argc - i, &argv[i], &consumed); 1323 if (IS_ERR(field)) { 1324 ret = PTR_ERR(field); 1325 goto err; 1326 } 1327 fields[n_fields++] = field; 1328 i += consumed - 1; 1329 } 1330 1331 if (i < argc && strcmp(argv[i], ";") != 0) { 1332 ret = -EINVAL; 1333 goto err; 1334 } 1335 1336 event = alloc_synth_event(name, n_fields, fields); 1337 if (IS_ERR(event)) { 1338 ret = PTR_ERR(event); 1339 event = NULL; 1340 goto err; 1341 } 1342 ret = register_synth_event(event); 1343 if (!ret) 1344 dyn_event_add(&event->devent); 1345 else 1346 free_synth_event(event); 1347 out: 1348 mutex_unlock(&event_mutex); 1349 1350 return ret; 1351 err: 1352 for (i = 0; i < n_fields; i++) 1353 free_synth_field(fields[i]); 1354 1355 goto out; 1356 } 1357 1358 static int create_or_delete_synth_event(int argc, char **argv) 1359 { 1360 const char *name = argv[0]; 1361 struct synth_event *event = NULL; 1362 int ret; 1363 1364 /* trace_run_command() ensures argc != 0 */ 1365 if (name[0] == '!') { 1366 mutex_lock(&event_mutex); 1367 event = find_synth_event(name + 1); 1368 if (event) { 1369 if (event->ref) 1370 ret = -EBUSY; 1371 else { 1372 ret = unregister_synth_event(event); 1373 if (!ret) { 1374 dyn_event_remove(&event->devent); 1375 free_synth_event(event); 1376 } 1377 } 1378 } else 1379 ret = -ENOENT; 1380 mutex_unlock(&event_mutex); 1381 return ret; 1382 } 1383 1384 ret = __create_synth_event(argc - 1, name, (const char **)argv + 1); 1385 return ret == -ECANCELED ? -EINVAL : ret; 1386 } 1387 1388 static int synth_event_create(int argc, const char **argv) 1389 { 1390 const char *name = argv[0]; 1391 int len; 1392 1393 if (name[0] != 's' || name[1] != ':') 1394 return -ECANCELED; 1395 name += 2; 1396 1397 /* This interface accepts group name prefix */ 1398 if (strchr(name, '/')) { 1399 len = str_has_prefix(name, SYNTH_SYSTEM "/"); 1400 if (len == 0) 1401 return -EINVAL; 1402 name += len; 1403 } 1404 return __create_synth_event(argc - 1, name, argv + 1); 1405 } 1406 1407 static int synth_event_release(struct dyn_event *ev) 1408 { 1409 struct synth_event *event = to_synth_event(ev); 1410 int ret; 1411 1412 if (event->ref) 1413 return -EBUSY; 1414 1415 ret = unregister_synth_event(event); 1416 if (ret) 1417 return ret; 1418 1419 dyn_event_remove(ev); 1420 free_synth_event(event); 1421 return 0; 1422 } 1423 1424 static int __synth_event_show(struct seq_file *m, struct synth_event *event) 1425 { 1426 struct synth_field *field; 1427 unsigned int i; 1428 1429 seq_printf(m, "%s\t", event->name); 1430 1431 for (i = 0; i < event->n_fields; i++) { 1432 field = event->fields[i]; 1433 1434 /* parameter values */ 1435 seq_printf(m, "%s %s%s", field->type, field->name, 1436 i == event->n_fields - 1 ? "" : "; "); 1437 } 1438 1439 seq_putc(m, '\n'); 1440 1441 return 0; 1442 } 1443 1444 static int synth_event_show(struct seq_file *m, struct dyn_event *ev) 1445 { 1446 struct synth_event *event = to_synth_event(ev); 1447 1448 seq_printf(m, "s:%s/", event->class.system); 1449 1450 return __synth_event_show(m, event); 1451 } 1452 1453 static int synth_events_seq_show(struct seq_file *m, void *v) 1454 { 1455 struct dyn_event *ev = v; 1456 1457 if (!is_synth_event(ev)) 1458 return 0; 1459 1460 return __synth_event_show(m, to_synth_event(ev)); 1461 } 1462 1463 static const struct seq_operations synth_events_seq_op = { 1464 .start = dyn_event_seq_start, 1465 .next = dyn_event_seq_next, 1466 .stop = dyn_event_seq_stop, 1467 .show = synth_events_seq_show, 1468 }; 1469 1470 static int synth_events_open(struct inode *inode, struct file *file) 1471 { 1472 int ret; 1473 1474 ret = security_locked_down(LOCKDOWN_TRACEFS); 1475 if (ret) 1476 return ret; 1477 1478 if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) { 1479 ret = dyn_events_release_all(&synth_event_ops); 1480 if (ret < 0) 1481 return ret; 1482 } 1483 1484 return seq_open(file, &synth_events_seq_op); 1485 } 1486 1487 static ssize_t synth_events_write(struct file *file, 1488 const char __user *buffer, 1489 size_t count, loff_t *ppos) 1490 { 1491 return trace_parse_run_command(file, buffer, count, ppos, 1492 create_or_delete_synth_event); 1493 } 1494 1495 static const struct file_operations synth_events_fops = { 1496 .open = synth_events_open, 1497 .write = synth_events_write, 1498 .read = seq_read, 1499 .llseek = seq_lseek, 1500 .release = seq_release, 1501 }; 1502 1503 static u64 hist_field_timestamp(struct hist_field *hist_field, 1504 struct tracing_map_elt *elt, 1505 struct ring_buffer_event *rbe, 1506 void *event) 1507 { 1508 struct hist_trigger_data *hist_data = hist_field->hist_data; 1509 struct trace_array *tr = hist_data->event_file->tr; 1510 1511 u64 ts = ring_buffer_event_time_stamp(rbe); 1512 1513 if (hist_data->attrs->ts_in_usecs && trace_clock_in_ns(tr)) 1514 ts = ns2usecs(ts); 1515 1516 return ts; 1517 } 1518 1519 static u64 hist_field_cpu(struct hist_field *hist_field, 1520 struct tracing_map_elt *elt, 1521 struct ring_buffer_event *rbe, 1522 void *event) 1523 { 1524 int cpu = smp_processor_id(); 1525 1526 return cpu; 1527 } 1528 1529 /** 1530 * check_field_for_var_ref - Check if a VAR_REF field references a variable 1531 * @hist_field: The VAR_REF field to check 1532 * @var_data: The hist trigger that owns the variable 1533 * @var_idx: The trigger variable identifier 1534 * 1535 * Check the given VAR_REF field to see whether or not it references 1536 * the given variable associated with the given trigger. 1537 * 1538 * Return: The VAR_REF field if it does reference the variable, NULL if not 1539 */ 1540 static struct hist_field * 1541 check_field_for_var_ref(struct hist_field *hist_field, 1542 struct hist_trigger_data *var_data, 1543 unsigned int var_idx) 1544 { 1545 WARN_ON(!(hist_field && hist_field->flags & HIST_FIELD_FL_VAR_REF)); 1546 1547 if (hist_field && hist_field->var.idx == var_idx && 1548 hist_field->var.hist_data == var_data) 1549 return hist_field; 1550 1551 return NULL; 1552 } 1553 1554 /** 1555 * find_var_ref - Check if a trigger has a reference to a trigger variable 1556 * @hist_data: The hist trigger that might have a reference to the variable 1557 * @var_data: The hist trigger that owns the variable 1558 * @var_idx: The trigger variable identifier 1559 * 1560 * Check the list of var_refs[] on the first hist trigger to see 1561 * whether any of them are references to the variable on the second 1562 * trigger. 1563 * 1564 * Return: The VAR_REF field referencing the variable if so, NULL if not 1565 */ 1566 static struct hist_field *find_var_ref(struct hist_trigger_data *hist_data, 1567 struct hist_trigger_data *var_data, 1568 unsigned int var_idx) 1569 { 1570 struct hist_field *hist_field; 1571 unsigned int i; 1572 1573 for (i = 0; i < hist_data->n_var_refs; i++) { 1574 hist_field = hist_data->var_refs[i]; 1575 if (check_field_for_var_ref(hist_field, var_data, var_idx)) 1576 return hist_field; 1577 } 1578 1579 return NULL; 1580 } 1581 1582 /** 1583 * find_any_var_ref - Check if there is a reference to a given trigger variable 1584 * @hist_data: The hist trigger 1585 * @var_idx: The trigger variable identifier 1586 * 1587 * Check to see whether the given variable is currently referenced by 1588 * any other trigger. 1589 * 1590 * The trigger the variable is defined on is explicitly excluded - the 1591 * assumption being that a self-reference doesn't prevent a trigger 1592 * from being removed. 1593 * 1594 * Return: The VAR_REF field referencing the variable if so, NULL if not 1595 */ 1596 static struct hist_field *find_any_var_ref(struct hist_trigger_data *hist_data, 1597 unsigned int var_idx) 1598 { 1599 struct trace_array *tr = hist_data->event_file->tr; 1600 struct hist_field *found = NULL; 1601 struct hist_var_data *var_data; 1602 1603 list_for_each_entry(var_data, &tr->hist_vars, list) { 1604 if (var_data->hist_data == hist_data) 1605 continue; 1606 found = find_var_ref(var_data->hist_data, hist_data, var_idx); 1607 if (found) 1608 break; 1609 } 1610 1611 return found; 1612 } 1613 1614 /** 1615 * check_var_refs - Check if there is a reference to any of trigger's variables 1616 * @hist_data: The hist trigger 1617 * 1618 * A trigger can define one or more variables. If any one of them is 1619 * currently referenced by any other trigger, this function will 1620 * determine that. 1621 1622 * Typically used to determine whether or not a trigger can be removed 1623 * - if there are any references to a trigger's variables, it cannot. 1624 * 1625 * Return: True if there is a reference to any of trigger's variables 1626 */ 1627 static bool check_var_refs(struct hist_trigger_data *hist_data) 1628 { 1629 struct hist_field *field; 1630 bool found = false; 1631 int i; 1632 1633 for_each_hist_field(i, hist_data) { 1634 field = hist_data->fields[i]; 1635 if (field && field->flags & HIST_FIELD_FL_VAR) { 1636 if (find_any_var_ref(hist_data, field->var.idx)) { 1637 found = true; 1638 break; 1639 } 1640 } 1641 } 1642 1643 return found; 1644 } 1645 1646 static struct hist_var_data *find_hist_vars(struct hist_trigger_data *hist_data) 1647 { 1648 struct trace_array *tr = hist_data->event_file->tr; 1649 struct hist_var_data *var_data, *found = NULL; 1650 1651 list_for_each_entry(var_data, &tr->hist_vars, list) { 1652 if (var_data->hist_data == hist_data) { 1653 found = var_data; 1654 break; 1655 } 1656 } 1657 1658 return found; 1659 } 1660 1661 static bool field_has_hist_vars(struct hist_field *hist_field, 1662 unsigned int level) 1663 { 1664 int i; 1665 1666 if (level > 3) 1667 return false; 1668 1669 if (!hist_field) 1670 return false; 1671 1672 if (hist_field->flags & HIST_FIELD_FL_VAR || 1673 hist_field->flags & HIST_FIELD_FL_VAR_REF) 1674 return true; 1675 1676 for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++) { 1677 struct hist_field *operand; 1678 1679 operand = hist_field->operands[i]; 1680 if (field_has_hist_vars(operand, level + 1)) 1681 return true; 1682 } 1683 1684 return false; 1685 } 1686 1687 static bool has_hist_vars(struct hist_trigger_data *hist_data) 1688 { 1689 struct hist_field *hist_field; 1690 int i; 1691 1692 for_each_hist_field(i, hist_data) { 1693 hist_field = hist_data->fields[i]; 1694 if (field_has_hist_vars(hist_field, 0)) 1695 return true; 1696 } 1697 1698 return false; 1699 } 1700 1701 static int save_hist_vars(struct hist_trigger_data *hist_data) 1702 { 1703 struct trace_array *tr = hist_data->event_file->tr; 1704 struct hist_var_data *var_data; 1705 1706 var_data = find_hist_vars(hist_data); 1707 if (var_data) 1708 return 0; 1709 1710 if (tracing_check_open_get_tr(tr)) 1711 return -ENODEV; 1712 1713 var_data = kzalloc(sizeof(*var_data), GFP_KERNEL); 1714 if (!var_data) { 1715 trace_array_put(tr); 1716 return -ENOMEM; 1717 } 1718 1719 var_data->hist_data = hist_data; 1720 list_add(&var_data->list, &tr->hist_vars); 1721 1722 return 0; 1723 } 1724 1725 static void remove_hist_vars(struct hist_trigger_data *hist_data) 1726 { 1727 struct trace_array *tr = hist_data->event_file->tr; 1728 struct hist_var_data *var_data; 1729 1730 var_data = find_hist_vars(hist_data); 1731 if (!var_data) 1732 return; 1733 1734 if (WARN_ON(check_var_refs(hist_data))) 1735 return; 1736 1737 list_del(&var_data->list); 1738 1739 kfree(var_data); 1740 1741 trace_array_put(tr); 1742 } 1743 1744 static struct hist_field *find_var_field(struct hist_trigger_data *hist_data, 1745 const char *var_name) 1746 { 1747 struct hist_field *hist_field, *found = NULL; 1748 int i; 1749 1750 for_each_hist_field(i, hist_data) { 1751 hist_field = hist_data->fields[i]; 1752 if (hist_field && hist_field->flags & HIST_FIELD_FL_VAR && 1753 strcmp(hist_field->var.name, var_name) == 0) { 1754 found = hist_field; 1755 break; 1756 } 1757 } 1758 1759 return found; 1760 } 1761 1762 static struct hist_field *find_var(struct hist_trigger_data *hist_data, 1763 struct trace_event_file *file, 1764 const char *var_name) 1765 { 1766 struct hist_trigger_data *test_data; 1767 struct event_trigger_data *test; 1768 struct hist_field *hist_field; 1769 1770 lockdep_assert_held(&event_mutex); 1771 1772 hist_field = find_var_field(hist_data, var_name); 1773 if (hist_field) 1774 return hist_field; 1775 1776 list_for_each_entry(test, &file->triggers, list) { 1777 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 1778 test_data = test->private_data; 1779 hist_field = find_var_field(test_data, var_name); 1780 if (hist_field) 1781 return hist_field; 1782 } 1783 } 1784 1785 return NULL; 1786 } 1787 1788 static struct trace_event_file *find_var_file(struct trace_array *tr, 1789 char *system, 1790 char *event_name, 1791 char *var_name) 1792 { 1793 struct hist_trigger_data *var_hist_data; 1794 struct hist_var_data *var_data; 1795 struct trace_event_file *file, *found = NULL; 1796 1797 if (system) 1798 return find_event_file(tr, system, event_name); 1799 1800 list_for_each_entry(var_data, &tr->hist_vars, list) { 1801 var_hist_data = var_data->hist_data; 1802 file = var_hist_data->event_file; 1803 if (file == found) 1804 continue; 1805 1806 if (find_var_field(var_hist_data, var_name)) { 1807 if (found) { 1808 hist_err(tr, HIST_ERR_VAR_NOT_UNIQUE, errpos(var_name)); 1809 return NULL; 1810 } 1811 1812 found = file; 1813 } 1814 } 1815 1816 return found; 1817 } 1818 1819 static struct hist_field *find_file_var(struct trace_event_file *file, 1820 const char *var_name) 1821 { 1822 struct hist_trigger_data *test_data; 1823 struct event_trigger_data *test; 1824 struct hist_field *hist_field; 1825 1826 lockdep_assert_held(&event_mutex); 1827 1828 list_for_each_entry(test, &file->triggers, list) { 1829 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 1830 test_data = test->private_data; 1831 hist_field = find_var_field(test_data, var_name); 1832 if (hist_field) 1833 return hist_field; 1834 } 1835 } 1836 1837 return NULL; 1838 } 1839 1840 static struct hist_field * 1841 find_match_var(struct hist_trigger_data *hist_data, char *var_name) 1842 { 1843 struct trace_array *tr = hist_data->event_file->tr; 1844 struct hist_field *hist_field, *found = NULL; 1845 struct trace_event_file *file; 1846 unsigned int i; 1847 1848 for (i = 0; i < hist_data->n_actions; i++) { 1849 struct action_data *data = hist_data->actions[i]; 1850 1851 if (data->handler == HANDLER_ONMATCH) { 1852 char *system = data->match_data.event_system; 1853 char *event_name = data->match_data.event; 1854 1855 file = find_var_file(tr, system, event_name, var_name); 1856 if (!file) 1857 continue; 1858 hist_field = find_file_var(file, var_name); 1859 if (hist_field) { 1860 if (found) { 1861 hist_err(tr, HIST_ERR_VAR_NOT_UNIQUE, 1862 errpos(var_name)); 1863 return ERR_PTR(-EINVAL); 1864 } 1865 1866 found = hist_field; 1867 } 1868 } 1869 } 1870 return found; 1871 } 1872 1873 static struct hist_field *find_event_var(struct hist_trigger_data *hist_data, 1874 char *system, 1875 char *event_name, 1876 char *var_name) 1877 { 1878 struct trace_array *tr = hist_data->event_file->tr; 1879 struct hist_field *hist_field = NULL; 1880 struct trace_event_file *file; 1881 1882 if (!system || !event_name) { 1883 hist_field = find_match_var(hist_data, var_name); 1884 if (IS_ERR(hist_field)) 1885 return NULL; 1886 if (hist_field) 1887 return hist_field; 1888 } 1889 1890 file = find_var_file(tr, system, event_name, var_name); 1891 if (!file) 1892 return NULL; 1893 1894 hist_field = find_file_var(file, var_name); 1895 1896 return hist_field; 1897 } 1898 1899 static u64 hist_field_var_ref(struct hist_field *hist_field, 1900 struct tracing_map_elt *elt, 1901 struct ring_buffer_event *rbe, 1902 void *event) 1903 { 1904 struct hist_elt_data *elt_data; 1905 u64 var_val = 0; 1906 1907 if (WARN_ON_ONCE(!elt)) 1908 return var_val; 1909 1910 elt_data = elt->private_data; 1911 var_val = elt_data->var_ref_vals[hist_field->var_ref_idx]; 1912 1913 return var_val; 1914 } 1915 1916 static bool resolve_var_refs(struct hist_trigger_data *hist_data, void *key, 1917 u64 *var_ref_vals, bool self) 1918 { 1919 struct hist_trigger_data *var_data; 1920 struct tracing_map_elt *var_elt; 1921 struct hist_field *hist_field; 1922 unsigned int i, var_idx; 1923 bool resolved = true; 1924 u64 var_val = 0; 1925 1926 for (i = 0; i < hist_data->n_var_refs; i++) { 1927 hist_field = hist_data->var_refs[i]; 1928 var_idx = hist_field->var.idx; 1929 var_data = hist_field->var.hist_data; 1930 1931 if (var_data == NULL) { 1932 resolved = false; 1933 break; 1934 } 1935 1936 if ((self && var_data != hist_data) || 1937 (!self && var_data == hist_data)) 1938 continue; 1939 1940 var_elt = tracing_map_lookup(var_data->map, key); 1941 if (!var_elt) { 1942 resolved = false; 1943 break; 1944 } 1945 1946 if (!tracing_map_var_set(var_elt, var_idx)) { 1947 resolved = false; 1948 break; 1949 } 1950 1951 if (self || !hist_field->read_once) 1952 var_val = tracing_map_read_var(var_elt, var_idx); 1953 else 1954 var_val = tracing_map_read_var_once(var_elt, var_idx); 1955 1956 var_ref_vals[i] = var_val; 1957 } 1958 1959 return resolved; 1960 } 1961 1962 static const char *hist_field_name(struct hist_field *field, 1963 unsigned int level) 1964 { 1965 const char *field_name = ""; 1966 1967 if (level > 1) 1968 return field_name; 1969 1970 if (field->field) 1971 field_name = field->field->name; 1972 else if (field->flags & HIST_FIELD_FL_LOG2 || 1973 field->flags & HIST_FIELD_FL_ALIAS) 1974 field_name = hist_field_name(field->operands[0], ++level); 1975 else if (field->flags & HIST_FIELD_FL_CPU) 1976 field_name = "cpu"; 1977 else if (field->flags & HIST_FIELD_FL_EXPR || 1978 field->flags & HIST_FIELD_FL_VAR_REF) { 1979 if (field->system) { 1980 static char full_name[MAX_FILTER_STR_VAL]; 1981 1982 strcat(full_name, field->system); 1983 strcat(full_name, "."); 1984 strcat(full_name, field->event_name); 1985 strcat(full_name, "."); 1986 strcat(full_name, field->name); 1987 field_name = full_name; 1988 } else 1989 field_name = field->name; 1990 } else if (field->flags & HIST_FIELD_FL_TIMESTAMP) 1991 field_name = "common_timestamp"; 1992 1993 if (field_name == NULL) 1994 field_name = ""; 1995 1996 return field_name; 1997 } 1998 1999 static hist_field_fn_t select_value_fn(int field_size, int field_is_signed) 2000 { 2001 hist_field_fn_t fn = NULL; 2002 2003 switch (field_size) { 2004 case 8: 2005 if (field_is_signed) 2006 fn = hist_field_s64; 2007 else 2008 fn = hist_field_u64; 2009 break; 2010 case 4: 2011 if (field_is_signed) 2012 fn = hist_field_s32; 2013 else 2014 fn = hist_field_u32; 2015 break; 2016 case 2: 2017 if (field_is_signed) 2018 fn = hist_field_s16; 2019 else 2020 fn = hist_field_u16; 2021 break; 2022 case 1: 2023 if (field_is_signed) 2024 fn = hist_field_s8; 2025 else 2026 fn = hist_field_u8; 2027 break; 2028 } 2029 2030 return fn; 2031 } 2032 2033 static int parse_map_size(char *str) 2034 { 2035 unsigned long size, map_bits; 2036 int ret; 2037 2038 strsep(&str, "="); 2039 if (!str) { 2040 ret = -EINVAL; 2041 goto out; 2042 } 2043 2044 ret = kstrtoul(str, 0, &size); 2045 if (ret) 2046 goto out; 2047 2048 map_bits = ilog2(roundup_pow_of_two(size)); 2049 if (map_bits < TRACING_MAP_BITS_MIN || 2050 map_bits > TRACING_MAP_BITS_MAX) 2051 ret = -EINVAL; 2052 else 2053 ret = map_bits; 2054 out: 2055 return ret; 2056 } 2057 2058 static void destroy_hist_trigger_attrs(struct hist_trigger_attrs *attrs) 2059 { 2060 unsigned int i; 2061 2062 if (!attrs) 2063 return; 2064 2065 for (i = 0; i < attrs->n_assignments; i++) 2066 kfree(attrs->assignment_str[i]); 2067 2068 for (i = 0; i < attrs->n_actions; i++) 2069 kfree(attrs->action_str[i]); 2070 2071 kfree(attrs->name); 2072 kfree(attrs->sort_key_str); 2073 kfree(attrs->keys_str); 2074 kfree(attrs->vals_str); 2075 kfree(attrs->clock); 2076 kfree(attrs); 2077 } 2078 2079 static int parse_action(char *str, struct hist_trigger_attrs *attrs) 2080 { 2081 int ret = -EINVAL; 2082 2083 if (attrs->n_actions >= HIST_ACTIONS_MAX) 2084 return ret; 2085 2086 if ((str_has_prefix(str, "onmatch(")) || 2087 (str_has_prefix(str, "onmax(")) || 2088 (str_has_prefix(str, "onchange("))) { 2089 attrs->action_str[attrs->n_actions] = kstrdup(str, GFP_KERNEL); 2090 if (!attrs->action_str[attrs->n_actions]) { 2091 ret = -ENOMEM; 2092 return ret; 2093 } 2094 attrs->n_actions++; 2095 ret = 0; 2096 } 2097 return ret; 2098 } 2099 2100 static int parse_assignment(struct trace_array *tr, 2101 char *str, struct hist_trigger_attrs *attrs) 2102 { 2103 int ret = 0; 2104 2105 if ((str_has_prefix(str, "key=")) || 2106 (str_has_prefix(str, "keys="))) { 2107 attrs->keys_str = kstrdup(str, GFP_KERNEL); 2108 if (!attrs->keys_str) { 2109 ret = -ENOMEM; 2110 goto out; 2111 } 2112 } else if ((str_has_prefix(str, "val=")) || 2113 (str_has_prefix(str, "vals=")) || 2114 (str_has_prefix(str, "values="))) { 2115 attrs->vals_str = kstrdup(str, GFP_KERNEL); 2116 if (!attrs->vals_str) { 2117 ret = -ENOMEM; 2118 goto out; 2119 } 2120 } else if (str_has_prefix(str, "sort=")) { 2121 attrs->sort_key_str = kstrdup(str, GFP_KERNEL); 2122 if (!attrs->sort_key_str) { 2123 ret = -ENOMEM; 2124 goto out; 2125 } 2126 } else if (str_has_prefix(str, "name=")) { 2127 attrs->name = kstrdup(str, GFP_KERNEL); 2128 if (!attrs->name) { 2129 ret = -ENOMEM; 2130 goto out; 2131 } 2132 } else if (str_has_prefix(str, "clock=")) { 2133 strsep(&str, "="); 2134 if (!str) { 2135 ret = -EINVAL; 2136 goto out; 2137 } 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 (str_has_prefix(str, "size=")) { 2146 int map_bits = parse_map_size(str); 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 2187 if (strchr(str, '=')) { 2188 ret = parse_assignment(tr, str, attrs); 2189 if (ret) 2190 goto free; 2191 } else if (strcmp(str, "pause") == 0) 2192 attrs->pause = true; 2193 else if ((strcmp(str, "cont") == 0) || 2194 (strcmp(str, "continue") == 0)) 2195 attrs->cont = true; 2196 else if (strcmp(str, "clear") == 0) 2197 attrs->clear = true; 2198 else { 2199 ret = parse_action(str, attrs); 2200 if (ret) 2201 goto free; 2202 } 2203 } 2204 2205 if (!attrs->keys_str) { 2206 ret = -EINVAL; 2207 goto free; 2208 } 2209 2210 if (!attrs->clock) { 2211 attrs->clock = kstrdup("global", GFP_KERNEL); 2212 if (!attrs->clock) { 2213 ret = -ENOMEM; 2214 goto free; 2215 } 2216 } 2217 2218 return attrs; 2219 free: 2220 destroy_hist_trigger_attrs(attrs); 2221 2222 return ERR_PTR(ret); 2223 } 2224 2225 static inline void save_comm(char *comm, struct task_struct *task) 2226 { 2227 if (!task->pid) { 2228 strcpy(comm, "<idle>"); 2229 return; 2230 } 2231 2232 if (WARN_ON_ONCE(task->pid < 0)) { 2233 strcpy(comm, "<XXX>"); 2234 return; 2235 } 2236 2237 strncpy(comm, task->comm, TASK_COMM_LEN); 2238 } 2239 2240 static void hist_elt_data_free(struct hist_elt_data *elt_data) 2241 { 2242 unsigned int i; 2243 2244 for (i = 0; i < SYNTH_FIELDS_MAX; i++) 2245 kfree(elt_data->field_var_str[i]); 2246 2247 kfree(elt_data->comm); 2248 kfree(elt_data); 2249 } 2250 2251 static void hist_trigger_elt_data_free(struct tracing_map_elt *elt) 2252 { 2253 struct hist_elt_data *elt_data = elt->private_data; 2254 2255 hist_elt_data_free(elt_data); 2256 } 2257 2258 static int hist_trigger_elt_data_alloc(struct tracing_map_elt *elt) 2259 { 2260 struct hist_trigger_data *hist_data = elt->map->private_data; 2261 unsigned int size = TASK_COMM_LEN; 2262 struct hist_elt_data *elt_data; 2263 struct hist_field *key_field; 2264 unsigned int i, n_str; 2265 2266 elt_data = kzalloc(sizeof(*elt_data), GFP_KERNEL); 2267 if (!elt_data) 2268 return -ENOMEM; 2269 2270 for_each_hist_key_field(i, hist_data) { 2271 key_field = hist_data->fields[i]; 2272 2273 if (key_field->flags & HIST_FIELD_FL_EXECNAME) { 2274 elt_data->comm = kzalloc(size, GFP_KERNEL); 2275 if (!elt_data->comm) { 2276 kfree(elt_data); 2277 return -ENOMEM; 2278 } 2279 break; 2280 } 2281 } 2282 2283 n_str = hist_data->n_field_var_str + hist_data->n_save_var_str; 2284 2285 size = STR_VAR_LEN_MAX; 2286 2287 for (i = 0; i < n_str; i++) { 2288 elt_data->field_var_str[i] = kzalloc(size, GFP_KERNEL); 2289 if (!elt_data->field_var_str[i]) { 2290 hist_elt_data_free(elt_data); 2291 return -ENOMEM; 2292 } 2293 } 2294 2295 elt->private_data = elt_data; 2296 2297 return 0; 2298 } 2299 2300 static void hist_trigger_elt_data_init(struct tracing_map_elt *elt) 2301 { 2302 struct hist_elt_data *elt_data = elt->private_data; 2303 2304 if (elt_data->comm) 2305 save_comm(elt_data->comm, current); 2306 } 2307 2308 static const struct tracing_map_ops hist_trigger_elt_data_ops = { 2309 .elt_alloc = hist_trigger_elt_data_alloc, 2310 .elt_free = hist_trigger_elt_data_free, 2311 .elt_init = hist_trigger_elt_data_init, 2312 }; 2313 2314 static const char *get_hist_field_flags(struct hist_field *hist_field) 2315 { 2316 const char *flags_str = NULL; 2317 2318 if (hist_field->flags & HIST_FIELD_FL_HEX) 2319 flags_str = "hex"; 2320 else if (hist_field->flags & HIST_FIELD_FL_SYM) 2321 flags_str = "sym"; 2322 else if (hist_field->flags & HIST_FIELD_FL_SYM_OFFSET) 2323 flags_str = "sym-offset"; 2324 else if (hist_field->flags & HIST_FIELD_FL_EXECNAME) 2325 flags_str = "execname"; 2326 else if (hist_field->flags & HIST_FIELD_FL_SYSCALL) 2327 flags_str = "syscall"; 2328 else if (hist_field->flags & HIST_FIELD_FL_LOG2) 2329 flags_str = "log2"; 2330 else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP_USECS) 2331 flags_str = "usecs"; 2332 2333 return flags_str; 2334 } 2335 2336 static void expr_field_str(struct hist_field *field, char *expr) 2337 { 2338 if (field->flags & HIST_FIELD_FL_VAR_REF) 2339 strcat(expr, "$"); 2340 2341 strcat(expr, hist_field_name(field, 0)); 2342 2343 if (field->flags && !(field->flags & HIST_FIELD_FL_VAR_REF)) { 2344 const char *flags_str = get_hist_field_flags(field); 2345 2346 if (flags_str) { 2347 strcat(expr, "."); 2348 strcat(expr, flags_str); 2349 } 2350 } 2351 } 2352 2353 static char *expr_str(struct hist_field *field, unsigned int level) 2354 { 2355 char *expr; 2356 2357 if (level > 1) 2358 return NULL; 2359 2360 expr = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL); 2361 if (!expr) 2362 return NULL; 2363 2364 if (!field->operands[0]) { 2365 expr_field_str(field, expr); 2366 return expr; 2367 } 2368 2369 if (field->operator == FIELD_OP_UNARY_MINUS) { 2370 char *subexpr; 2371 2372 strcat(expr, "-("); 2373 subexpr = expr_str(field->operands[0], ++level); 2374 if (!subexpr) { 2375 kfree(expr); 2376 return NULL; 2377 } 2378 strcat(expr, subexpr); 2379 strcat(expr, ")"); 2380 2381 kfree(subexpr); 2382 2383 return expr; 2384 } 2385 2386 expr_field_str(field->operands[0], expr); 2387 2388 switch (field->operator) { 2389 case FIELD_OP_MINUS: 2390 strcat(expr, "-"); 2391 break; 2392 case FIELD_OP_PLUS: 2393 strcat(expr, "+"); 2394 break; 2395 default: 2396 kfree(expr); 2397 return NULL; 2398 } 2399 2400 expr_field_str(field->operands[1], expr); 2401 2402 return expr; 2403 } 2404 2405 static int contains_operator(char *str) 2406 { 2407 enum field_op_id field_op = FIELD_OP_NONE; 2408 char *op; 2409 2410 op = strpbrk(str, "+-"); 2411 if (!op) 2412 return FIELD_OP_NONE; 2413 2414 switch (*op) { 2415 case '-': 2416 if (*str == '-') 2417 field_op = FIELD_OP_UNARY_MINUS; 2418 else 2419 field_op = FIELD_OP_MINUS; 2420 break; 2421 case '+': 2422 field_op = FIELD_OP_PLUS; 2423 break; 2424 default: 2425 break; 2426 } 2427 2428 return field_op; 2429 } 2430 2431 static void get_hist_field(struct hist_field *hist_field) 2432 { 2433 hist_field->ref++; 2434 } 2435 2436 static void __destroy_hist_field(struct hist_field *hist_field) 2437 { 2438 if (--hist_field->ref > 1) 2439 return; 2440 2441 kfree(hist_field->var.name); 2442 kfree(hist_field->name); 2443 kfree(hist_field->type); 2444 2445 kfree(hist_field); 2446 } 2447 2448 static void destroy_hist_field(struct hist_field *hist_field, 2449 unsigned int level) 2450 { 2451 unsigned int i; 2452 2453 if (level > 3) 2454 return; 2455 2456 if (!hist_field) 2457 return; 2458 2459 if (hist_field->flags & HIST_FIELD_FL_VAR_REF) 2460 return; /* var refs will be destroyed separately */ 2461 2462 for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++) 2463 destroy_hist_field(hist_field->operands[i], level + 1); 2464 2465 __destroy_hist_field(hist_field); 2466 } 2467 2468 static struct hist_field *create_hist_field(struct hist_trigger_data *hist_data, 2469 struct ftrace_event_field *field, 2470 unsigned long flags, 2471 char *var_name) 2472 { 2473 struct hist_field *hist_field; 2474 2475 if (field && is_function_field(field)) 2476 return NULL; 2477 2478 hist_field = kzalloc(sizeof(struct hist_field), GFP_KERNEL); 2479 if (!hist_field) 2480 return NULL; 2481 2482 hist_field->ref = 1; 2483 2484 hist_field->hist_data = hist_data; 2485 2486 if (flags & HIST_FIELD_FL_EXPR || flags & HIST_FIELD_FL_ALIAS) 2487 goto out; /* caller will populate */ 2488 2489 if (flags & HIST_FIELD_FL_VAR_REF) { 2490 hist_field->fn = hist_field_var_ref; 2491 goto out; 2492 } 2493 2494 if (flags & HIST_FIELD_FL_HITCOUNT) { 2495 hist_field->fn = hist_field_counter; 2496 hist_field->size = sizeof(u64); 2497 hist_field->type = kstrdup("u64", GFP_KERNEL); 2498 if (!hist_field->type) 2499 goto free; 2500 goto out; 2501 } 2502 2503 if (flags & HIST_FIELD_FL_STACKTRACE) { 2504 hist_field->fn = hist_field_none; 2505 goto out; 2506 } 2507 2508 if (flags & HIST_FIELD_FL_LOG2) { 2509 unsigned long fl = flags & ~HIST_FIELD_FL_LOG2; 2510 hist_field->fn = hist_field_log2; 2511 hist_field->operands[0] = create_hist_field(hist_data, field, fl, NULL); 2512 hist_field->size = hist_field->operands[0]->size; 2513 hist_field->type = kstrdup(hist_field->operands[0]->type, GFP_KERNEL); 2514 if (!hist_field->type) 2515 goto free; 2516 goto out; 2517 } 2518 2519 if (flags & HIST_FIELD_FL_TIMESTAMP) { 2520 hist_field->fn = hist_field_timestamp; 2521 hist_field->size = sizeof(u64); 2522 hist_field->type = kstrdup("u64", GFP_KERNEL); 2523 if (!hist_field->type) 2524 goto free; 2525 goto out; 2526 } 2527 2528 if (flags & HIST_FIELD_FL_CPU) { 2529 hist_field->fn = hist_field_cpu; 2530 hist_field->size = sizeof(int); 2531 hist_field->type = kstrdup("unsigned int", GFP_KERNEL); 2532 if (!hist_field->type) 2533 goto free; 2534 goto out; 2535 } 2536 2537 if (WARN_ON_ONCE(!field)) 2538 goto out; 2539 2540 if (is_string_field(field)) { 2541 flags |= HIST_FIELD_FL_STRING; 2542 2543 hist_field->size = MAX_FILTER_STR_VAL; 2544 hist_field->type = kstrdup(field->type, GFP_KERNEL); 2545 if (!hist_field->type) 2546 goto free; 2547 2548 if (field->filter_type == FILTER_STATIC_STRING) 2549 hist_field->fn = hist_field_string; 2550 else if (field->filter_type == FILTER_DYN_STRING) 2551 hist_field->fn = hist_field_dynstring; 2552 else 2553 hist_field->fn = hist_field_pstring; 2554 } else { 2555 hist_field->size = field->size; 2556 hist_field->is_signed = field->is_signed; 2557 hist_field->type = kstrdup(field->type, GFP_KERNEL); 2558 if (!hist_field->type) 2559 goto free; 2560 2561 hist_field->fn = select_value_fn(field->size, 2562 field->is_signed); 2563 if (!hist_field->fn) { 2564 destroy_hist_field(hist_field, 0); 2565 return NULL; 2566 } 2567 } 2568 out: 2569 hist_field->field = field; 2570 hist_field->flags = flags; 2571 2572 if (var_name) { 2573 hist_field->var.name = kstrdup(var_name, GFP_KERNEL); 2574 if (!hist_field->var.name) 2575 goto free; 2576 } 2577 2578 return hist_field; 2579 free: 2580 destroy_hist_field(hist_field, 0); 2581 return NULL; 2582 } 2583 2584 static void destroy_hist_fields(struct hist_trigger_data *hist_data) 2585 { 2586 unsigned int i; 2587 2588 for (i = 0; i < HIST_FIELDS_MAX; i++) { 2589 if (hist_data->fields[i]) { 2590 destroy_hist_field(hist_data->fields[i], 0); 2591 hist_data->fields[i] = NULL; 2592 } 2593 } 2594 2595 for (i = 0; i < hist_data->n_var_refs; i++) { 2596 WARN_ON(!(hist_data->var_refs[i]->flags & HIST_FIELD_FL_VAR_REF)); 2597 __destroy_hist_field(hist_data->var_refs[i]); 2598 hist_data->var_refs[i] = NULL; 2599 } 2600 } 2601 2602 static int init_var_ref(struct hist_field *ref_field, 2603 struct hist_field *var_field, 2604 char *system, char *event_name) 2605 { 2606 int err = 0; 2607 2608 ref_field->var.idx = var_field->var.idx; 2609 ref_field->var.hist_data = var_field->hist_data; 2610 ref_field->size = var_field->size; 2611 ref_field->is_signed = var_field->is_signed; 2612 ref_field->flags |= var_field->flags & 2613 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS); 2614 2615 if (system) { 2616 ref_field->system = kstrdup(system, GFP_KERNEL); 2617 if (!ref_field->system) 2618 return -ENOMEM; 2619 } 2620 2621 if (event_name) { 2622 ref_field->event_name = kstrdup(event_name, GFP_KERNEL); 2623 if (!ref_field->event_name) { 2624 err = -ENOMEM; 2625 goto free; 2626 } 2627 } 2628 2629 if (var_field->var.name) { 2630 ref_field->name = kstrdup(var_field->var.name, GFP_KERNEL); 2631 if (!ref_field->name) { 2632 err = -ENOMEM; 2633 goto free; 2634 } 2635 } else if (var_field->name) { 2636 ref_field->name = kstrdup(var_field->name, GFP_KERNEL); 2637 if (!ref_field->name) { 2638 err = -ENOMEM; 2639 goto free; 2640 } 2641 } 2642 2643 ref_field->type = kstrdup(var_field->type, GFP_KERNEL); 2644 if (!ref_field->type) { 2645 err = -ENOMEM; 2646 goto free; 2647 } 2648 out: 2649 return err; 2650 free: 2651 kfree(ref_field->system); 2652 kfree(ref_field->event_name); 2653 kfree(ref_field->name); 2654 2655 goto out; 2656 } 2657 2658 /** 2659 * create_var_ref - Create a variable reference and attach it to trigger 2660 * @hist_data: The trigger that will be referencing the variable 2661 * @var_field: The VAR field to create a reference to 2662 * @system: The optional system string 2663 * @event_name: The optional event_name string 2664 * 2665 * Given a variable hist_field, create a VAR_REF hist_field that 2666 * represents a reference to it. 2667 * 2668 * This function also adds the reference to the trigger that 2669 * now references the variable. 2670 * 2671 * Return: The VAR_REF field if successful, NULL if not 2672 */ 2673 static struct hist_field *create_var_ref(struct hist_trigger_data *hist_data, 2674 struct hist_field *var_field, 2675 char *system, char *event_name) 2676 { 2677 unsigned long flags = HIST_FIELD_FL_VAR_REF; 2678 struct hist_field *ref_field; 2679 int i; 2680 2681 /* Check if the variable already exists */ 2682 for (i = 0; i < hist_data->n_var_refs; i++) { 2683 ref_field = hist_data->var_refs[i]; 2684 if (ref_field->var.idx == var_field->var.idx && 2685 ref_field->var.hist_data == var_field->hist_data) { 2686 get_hist_field(ref_field); 2687 return ref_field; 2688 } 2689 } 2690 2691 ref_field = create_hist_field(var_field->hist_data, NULL, flags, NULL); 2692 if (ref_field) { 2693 if (init_var_ref(ref_field, var_field, system, event_name)) { 2694 destroy_hist_field(ref_field, 0); 2695 return NULL; 2696 } 2697 2698 hist_data->var_refs[hist_data->n_var_refs] = ref_field; 2699 ref_field->var_ref_idx = hist_data->n_var_refs++; 2700 } 2701 2702 return ref_field; 2703 } 2704 2705 static bool is_var_ref(char *var_name) 2706 { 2707 if (!var_name || strlen(var_name) < 2 || var_name[0] != '$') 2708 return false; 2709 2710 return true; 2711 } 2712 2713 static char *field_name_from_var(struct hist_trigger_data *hist_data, 2714 char *var_name) 2715 { 2716 char *name, *field; 2717 unsigned int i; 2718 2719 for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) { 2720 name = hist_data->attrs->var_defs.name[i]; 2721 2722 if (strcmp(var_name, name) == 0) { 2723 field = hist_data->attrs->var_defs.expr[i]; 2724 if (contains_operator(field) || is_var_ref(field)) 2725 continue; 2726 return field; 2727 } 2728 } 2729 2730 return NULL; 2731 } 2732 2733 static char *local_field_var_ref(struct hist_trigger_data *hist_data, 2734 char *system, char *event_name, 2735 char *var_name) 2736 { 2737 struct trace_event_call *call; 2738 2739 if (system && event_name) { 2740 call = hist_data->event_file->event_call; 2741 2742 if (strcmp(system, call->class->system) != 0) 2743 return NULL; 2744 2745 if (strcmp(event_name, trace_event_name(call)) != 0) 2746 return NULL; 2747 } 2748 2749 if (!!system != !!event_name) 2750 return NULL; 2751 2752 if (!is_var_ref(var_name)) 2753 return NULL; 2754 2755 var_name++; 2756 2757 return field_name_from_var(hist_data, var_name); 2758 } 2759 2760 static struct hist_field *parse_var_ref(struct hist_trigger_data *hist_data, 2761 char *system, char *event_name, 2762 char *var_name) 2763 { 2764 struct hist_field *var_field = NULL, *ref_field = NULL; 2765 struct trace_array *tr = hist_data->event_file->tr; 2766 2767 if (!is_var_ref(var_name)) 2768 return NULL; 2769 2770 var_name++; 2771 2772 var_field = find_event_var(hist_data, system, event_name, var_name); 2773 if (var_field) 2774 ref_field = create_var_ref(hist_data, var_field, 2775 system, event_name); 2776 2777 if (!ref_field) 2778 hist_err(tr, HIST_ERR_VAR_NOT_FOUND, errpos(var_name)); 2779 2780 return ref_field; 2781 } 2782 2783 static struct ftrace_event_field * 2784 parse_field(struct hist_trigger_data *hist_data, struct trace_event_file *file, 2785 char *field_str, unsigned long *flags) 2786 { 2787 struct ftrace_event_field *field = NULL; 2788 char *field_name, *modifier, *str; 2789 struct trace_array *tr = file->tr; 2790 2791 modifier = str = kstrdup(field_str, GFP_KERNEL); 2792 if (!modifier) 2793 return ERR_PTR(-ENOMEM); 2794 2795 field_name = strsep(&modifier, "."); 2796 if (modifier) { 2797 if (strcmp(modifier, "hex") == 0) 2798 *flags |= HIST_FIELD_FL_HEX; 2799 else if (strcmp(modifier, "sym") == 0) 2800 *flags |= HIST_FIELD_FL_SYM; 2801 else if (strcmp(modifier, "sym-offset") == 0) 2802 *flags |= HIST_FIELD_FL_SYM_OFFSET; 2803 else if ((strcmp(modifier, "execname") == 0) && 2804 (strcmp(field_name, "common_pid") == 0)) 2805 *flags |= HIST_FIELD_FL_EXECNAME; 2806 else if (strcmp(modifier, "syscall") == 0) 2807 *flags |= HIST_FIELD_FL_SYSCALL; 2808 else if (strcmp(modifier, "log2") == 0) 2809 *flags |= HIST_FIELD_FL_LOG2; 2810 else if (strcmp(modifier, "usecs") == 0) 2811 *flags |= HIST_FIELD_FL_TIMESTAMP_USECS; 2812 else { 2813 hist_err(tr, HIST_ERR_BAD_FIELD_MODIFIER, errpos(modifier)); 2814 field = ERR_PTR(-EINVAL); 2815 goto out; 2816 } 2817 } 2818 2819 if (strcmp(field_name, "common_timestamp") == 0) { 2820 *flags |= HIST_FIELD_FL_TIMESTAMP; 2821 hist_data->enable_timestamps = true; 2822 if (*flags & HIST_FIELD_FL_TIMESTAMP_USECS) 2823 hist_data->attrs->ts_in_usecs = true; 2824 } else if (strcmp(field_name, "cpu") == 0) 2825 *flags |= HIST_FIELD_FL_CPU; 2826 else { 2827 field = trace_find_event_field(file->event_call, field_name); 2828 if (!field || !field->size) { 2829 hist_err(tr, HIST_ERR_FIELD_NOT_FOUND, errpos(field_name)); 2830 field = ERR_PTR(-EINVAL); 2831 goto out; 2832 } 2833 } 2834 out: 2835 kfree(str); 2836 2837 return field; 2838 } 2839 2840 static struct hist_field *create_alias(struct hist_trigger_data *hist_data, 2841 struct hist_field *var_ref, 2842 char *var_name) 2843 { 2844 struct hist_field *alias = NULL; 2845 unsigned long flags = HIST_FIELD_FL_ALIAS | HIST_FIELD_FL_VAR; 2846 2847 alias = create_hist_field(hist_data, NULL, flags, var_name); 2848 if (!alias) 2849 return NULL; 2850 2851 alias->fn = var_ref->fn; 2852 alias->operands[0] = var_ref; 2853 2854 if (init_var_ref(alias, var_ref, var_ref->system, var_ref->event_name)) { 2855 destroy_hist_field(alias, 0); 2856 return NULL; 2857 } 2858 2859 alias->var_ref_idx = var_ref->var_ref_idx; 2860 2861 return alias; 2862 } 2863 2864 static struct hist_field *parse_atom(struct hist_trigger_data *hist_data, 2865 struct trace_event_file *file, char *str, 2866 unsigned long *flags, char *var_name) 2867 { 2868 char *s, *ref_system = NULL, *ref_event = NULL, *ref_var = str; 2869 struct ftrace_event_field *field = NULL; 2870 struct hist_field *hist_field = NULL; 2871 int ret = 0; 2872 2873 s = strchr(str, '.'); 2874 if (s) { 2875 s = strchr(++s, '.'); 2876 if (s) { 2877 ref_system = strsep(&str, "."); 2878 if (!str) { 2879 ret = -EINVAL; 2880 goto out; 2881 } 2882 ref_event = strsep(&str, "."); 2883 if (!str) { 2884 ret = -EINVAL; 2885 goto out; 2886 } 2887 ref_var = str; 2888 } 2889 } 2890 2891 s = local_field_var_ref(hist_data, ref_system, ref_event, ref_var); 2892 if (!s) { 2893 hist_field = parse_var_ref(hist_data, ref_system, 2894 ref_event, ref_var); 2895 if (hist_field) { 2896 if (var_name) { 2897 hist_field = create_alias(hist_data, hist_field, var_name); 2898 if (!hist_field) { 2899 ret = -ENOMEM; 2900 goto out; 2901 } 2902 } 2903 return hist_field; 2904 } 2905 } else 2906 str = s; 2907 2908 field = parse_field(hist_data, file, str, flags); 2909 if (IS_ERR(field)) { 2910 ret = PTR_ERR(field); 2911 goto out; 2912 } 2913 2914 hist_field = create_hist_field(hist_data, field, *flags, var_name); 2915 if (!hist_field) { 2916 ret = -ENOMEM; 2917 goto out; 2918 } 2919 2920 return hist_field; 2921 out: 2922 return ERR_PTR(ret); 2923 } 2924 2925 static struct hist_field *parse_expr(struct hist_trigger_data *hist_data, 2926 struct trace_event_file *file, 2927 char *str, unsigned long flags, 2928 char *var_name, unsigned int level); 2929 2930 static struct hist_field *parse_unary(struct hist_trigger_data *hist_data, 2931 struct trace_event_file *file, 2932 char *str, unsigned long flags, 2933 char *var_name, unsigned int level) 2934 { 2935 struct hist_field *operand1, *expr = NULL; 2936 unsigned long operand_flags; 2937 int ret = 0; 2938 char *s; 2939 2940 /* we support only -(xxx) i.e. explicit parens required */ 2941 2942 if (level > 3) { 2943 hist_err(file->tr, HIST_ERR_TOO_MANY_SUBEXPR, errpos(str)); 2944 ret = -EINVAL; 2945 goto free; 2946 } 2947 2948 str++; /* skip leading '-' */ 2949 2950 s = strchr(str, '('); 2951 if (s) 2952 str++; 2953 else { 2954 ret = -EINVAL; 2955 goto free; 2956 } 2957 2958 s = strrchr(str, ')'); 2959 if (s) 2960 *s = '\0'; 2961 else { 2962 ret = -EINVAL; /* no closing ')' */ 2963 goto free; 2964 } 2965 2966 flags |= HIST_FIELD_FL_EXPR; 2967 expr = create_hist_field(hist_data, NULL, flags, var_name); 2968 if (!expr) { 2969 ret = -ENOMEM; 2970 goto free; 2971 } 2972 2973 operand_flags = 0; 2974 operand1 = parse_expr(hist_data, file, str, operand_flags, NULL, ++level); 2975 if (IS_ERR(operand1)) { 2976 ret = PTR_ERR(operand1); 2977 goto free; 2978 } 2979 2980 expr->flags |= operand1->flags & 2981 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS); 2982 expr->fn = hist_field_unary_minus; 2983 expr->operands[0] = operand1; 2984 expr->operator = FIELD_OP_UNARY_MINUS; 2985 expr->name = expr_str(expr, 0); 2986 expr->type = kstrdup(operand1->type, GFP_KERNEL); 2987 if (!expr->type) { 2988 ret = -ENOMEM; 2989 goto free; 2990 } 2991 2992 return expr; 2993 free: 2994 destroy_hist_field(expr, 0); 2995 return ERR_PTR(ret); 2996 } 2997 2998 static int check_expr_operands(struct trace_array *tr, 2999 struct hist_field *operand1, 3000 struct hist_field *operand2) 3001 { 3002 unsigned long operand1_flags = operand1->flags; 3003 unsigned long operand2_flags = operand2->flags; 3004 3005 if ((operand1_flags & HIST_FIELD_FL_VAR_REF) || 3006 (operand1_flags & HIST_FIELD_FL_ALIAS)) { 3007 struct hist_field *var; 3008 3009 var = find_var_field(operand1->var.hist_data, operand1->name); 3010 if (!var) 3011 return -EINVAL; 3012 operand1_flags = var->flags; 3013 } 3014 3015 if ((operand2_flags & HIST_FIELD_FL_VAR_REF) || 3016 (operand2_flags & HIST_FIELD_FL_ALIAS)) { 3017 struct hist_field *var; 3018 3019 var = find_var_field(operand2->var.hist_data, operand2->name); 3020 if (!var) 3021 return -EINVAL; 3022 operand2_flags = var->flags; 3023 } 3024 3025 if ((operand1_flags & HIST_FIELD_FL_TIMESTAMP_USECS) != 3026 (operand2_flags & HIST_FIELD_FL_TIMESTAMP_USECS)) { 3027 hist_err(tr, HIST_ERR_TIMESTAMP_MISMATCH, 0); 3028 return -EINVAL; 3029 } 3030 3031 return 0; 3032 } 3033 3034 static struct hist_field *parse_expr(struct hist_trigger_data *hist_data, 3035 struct trace_event_file *file, 3036 char *str, unsigned long flags, 3037 char *var_name, unsigned int level) 3038 { 3039 struct hist_field *operand1 = NULL, *operand2 = NULL, *expr = NULL; 3040 unsigned long operand_flags; 3041 int field_op, ret = -EINVAL; 3042 char *sep, *operand1_str; 3043 3044 if (level > 3) { 3045 hist_err(file->tr, HIST_ERR_TOO_MANY_SUBEXPR, errpos(str)); 3046 return ERR_PTR(-EINVAL); 3047 } 3048 3049 field_op = contains_operator(str); 3050 3051 if (field_op == FIELD_OP_NONE) 3052 return parse_atom(hist_data, file, str, &flags, var_name); 3053 3054 if (field_op == FIELD_OP_UNARY_MINUS) 3055 return parse_unary(hist_data, file, str, flags, var_name, ++level); 3056 3057 switch (field_op) { 3058 case FIELD_OP_MINUS: 3059 sep = "-"; 3060 break; 3061 case FIELD_OP_PLUS: 3062 sep = "+"; 3063 break; 3064 default: 3065 goto free; 3066 } 3067 3068 operand1_str = strsep(&str, sep); 3069 if (!operand1_str || !str) 3070 goto free; 3071 3072 operand_flags = 0; 3073 operand1 = parse_atom(hist_data, file, operand1_str, 3074 &operand_flags, NULL); 3075 if (IS_ERR(operand1)) { 3076 ret = PTR_ERR(operand1); 3077 operand1 = NULL; 3078 goto free; 3079 } 3080 3081 /* rest of string could be another expression e.g. b+c in a+b+c */ 3082 operand_flags = 0; 3083 operand2 = parse_expr(hist_data, file, str, operand_flags, NULL, ++level); 3084 if (IS_ERR(operand2)) { 3085 ret = PTR_ERR(operand2); 3086 operand2 = NULL; 3087 goto free; 3088 } 3089 3090 ret = check_expr_operands(file->tr, operand1, operand2); 3091 if (ret) 3092 goto free; 3093 3094 flags |= HIST_FIELD_FL_EXPR; 3095 3096 flags |= operand1->flags & 3097 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS); 3098 3099 expr = create_hist_field(hist_data, NULL, flags, var_name); 3100 if (!expr) { 3101 ret = -ENOMEM; 3102 goto free; 3103 } 3104 3105 operand1->read_once = true; 3106 operand2->read_once = true; 3107 3108 expr->operands[0] = operand1; 3109 expr->operands[1] = operand2; 3110 expr->operator = field_op; 3111 expr->name = expr_str(expr, 0); 3112 expr->type = kstrdup(operand1->type, GFP_KERNEL); 3113 if (!expr->type) { 3114 ret = -ENOMEM; 3115 goto free; 3116 } 3117 3118 switch (field_op) { 3119 case FIELD_OP_MINUS: 3120 expr->fn = hist_field_minus; 3121 break; 3122 case FIELD_OP_PLUS: 3123 expr->fn = hist_field_plus; 3124 break; 3125 default: 3126 ret = -EINVAL; 3127 goto free; 3128 } 3129 3130 return expr; 3131 free: 3132 destroy_hist_field(operand1, 0); 3133 destroy_hist_field(operand2, 0); 3134 destroy_hist_field(expr, 0); 3135 3136 return ERR_PTR(ret); 3137 } 3138 3139 static char *find_trigger_filter(struct hist_trigger_data *hist_data, 3140 struct trace_event_file *file) 3141 { 3142 struct event_trigger_data *test; 3143 3144 lockdep_assert_held(&event_mutex); 3145 3146 list_for_each_entry(test, &file->triggers, list) { 3147 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 3148 if (test->private_data == hist_data) 3149 return test->filter_str; 3150 } 3151 } 3152 3153 return NULL; 3154 } 3155 3156 static struct event_command trigger_hist_cmd; 3157 static int event_hist_trigger_func(struct event_command *cmd_ops, 3158 struct trace_event_file *file, 3159 char *glob, char *cmd, char *param); 3160 3161 static bool compatible_keys(struct hist_trigger_data *target_hist_data, 3162 struct hist_trigger_data *hist_data, 3163 unsigned int n_keys) 3164 { 3165 struct hist_field *target_hist_field, *hist_field; 3166 unsigned int n, i, j; 3167 3168 if (hist_data->n_fields - hist_data->n_vals != n_keys) 3169 return false; 3170 3171 i = hist_data->n_vals; 3172 j = target_hist_data->n_vals; 3173 3174 for (n = 0; n < n_keys; n++) { 3175 hist_field = hist_data->fields[i + n]; 3176 target_hist_field = target_hist_data->fields[j + n]; 3177 3178 if (strcmp(hist_field->type, target_hist_field->type) != 0) 3179 return false; 3180 if (hist_field->size != target_hist_field->size) 3181 return false; 3182 if (hist_field->is_signed != target_hist_field->is_signed) 3183 return false; 3184 } 3185 3186 return true; 3187 } 3188 3189 static struct hist_trigger_data * 3190 find_compatible_hist(struct hist_trigger_data *target_hist_data, 3191 struct trace_event_file *file) 3192 { 3193 struct hist_trigger_data *hist_data; 3194 struct event_trigger_data *test; 3195 unsigned int n_keys; 3196 3197 lockdep_assert_held(&event_mutex); 3198 3199 n_keys = target_hist_data->n_fields - target_hist_data->n_vals; 3200 3201 list_for_each_entry(test, &file->triggers, list) { 3202 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 3203 hist_data = test->private_data; 3204 3205 if (compatible_keys(target_hist_data, hist_data, n_keys)) 3206 return hist_data; 3207 } 3208 } 3209 3210 return NULL; 3211 } 3212 3213 static struct trace_event_file *event_file(struct trace_array *tr, 3214 char *system, char *event_name) 3215 { 3216 struct trace_event_file *file; 3217 3218 file = __find_event_file(tr, system, event_name); 3219 if (!file) 3220 return ERR_PTR(-EINVAL); 3221 3222 return file; 3223 } 3224 3225 static struct hist_field * 3226 find_synthetic_field_var(struct hist_trigger_data *target_hist_data, 3227 char *system, char *event_name, char *field_name) 3228 { 3229 struct hist_field *event_var; 3230 char *synthetic_name; 3231 3232 synthetic_name = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL); 3233 if (!synthetic_name) 3234 return ERR_PTR(-ENOMEM); 3235 3236 strcpy(synthetic_name, "synthetic_"); 3237 strcat(synthetic_name, field_name); 3238 3239 event_var = find_event_var(target_hist_data, system, event_name, synthetic_name); 3240 3241 kfree(synthetic_name); 3242 3243 return event_var; 3244 } 3245 3246 /** 3247 * create_field_var_hist - Automatically create a histogram and var for a field 3248 * @target_hist_data: The target hist trigger 3249 * @subsys_name: Optional subsystem name 3250 * @event_name: Optional event name 3251 * @field_name: The name of the field (and the resulting variable) 3252 * 3253 * Hist trigger actions fetch data from variables, not directly from 3254 * events. However, for convenience, users are allowed to directly 3255 * specify an event field in an action, which will be automatically 3256 * converted into a variable on their behalf. 3257 3258 * If a user specifies a field on an event that isn't the event the 3259 * histogram currently being defined (the target event histogram), the 3260 * only way that can be accomplished is if a new hist trigger is 3261 * created and the field variable defined on that. 3262 * 3263 * This function creates a new histogram compatible with the target 3264 * event (meaning a histogram with the same key as the target 3265 * histogram), and creates a variable for the specified field, but 3266 * with 'synthetic_' prepended to the variable name in order to avoid 3267 * collision with normal field variables. 3268 * 3269 * Return: The variable created for the field. 3270 */ 3271 static struct hist_field * 3272 create_field_var_hist(struct hist_trigger_data *target_hist_data, 3273 char *subsys_name, char *event_name, char *field_name) 3274 { 3275 struct trace_array *tr = target_hist_data->event_file->tr; 3276 struct hist_field *event_var = ERR_PTR(-EINVAL); 3277 struct hist_trigger_data *hist_data; 3278 unsigned int i, n, first = true; 3279 struct field_var_hist *var_hist; 3280 struct trace_event_file *file; 3281 struct hist_field *key_field; 3282 char *saved_filter; 3283 char *cmd; 3284 int ret; 3285 3286 if (target_hist_data->n_field_var_hists >= SYNTH_FIELDS_MAX) { 3287 hist_err(tr, HIST_ERR_TOO_MANY_FIELD_VARS, errpos(field_name)); 3288 return ERR_PTR(-EINVAL); 3289 } 3290 3291 file = event_file(tr, subsys_name, event_name); 3292 3293 if (IS_ERR(file)) { 3294 hist_err(tr, HIST_ERR_EVENT_FILE_NOT_FOUND, errpos(field_name)); 3295 ret = PTR_ERR(file); 3296 return ERR_PTR(ret); 3297 } 3298 3299 /* 3300 * Look for a histogram compatible with target. We'll use the 3301 * found histogram specification to create a new matching 3302 * histogram with our variable on it. target_hist_data is not 3303 * yet a registered histogram so we can't use that. 3304 */ 3305 hist_data = find_compatible_hist(target_hist_data, file); 3306 if (!hist_data) { 3307 hist_err(tr, HIST_ERR_HIST_NOT_FOUND, errpos(field_name)); 3308 return ERR_PTR(-EINVAL); 3309 } 3310 3311 /* See if a synthetic field variable has already been created */ 3312 event_var = find_synthetic_field_var(target_hist_data, subsys_name, 3313 event_name, field_name); 3314 if (!IS_ERR_OR_NULL(event_var)) 3315 return event_var; 3316 3317 var_hist = kzalloc(sizeof(*var_hist), GFP_KERNEL); 3318 if (!var_hist) 3319 return ERR_PTR(-ENOMEM); 3320 3321 cmd = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL); 3322 if (!cmd) { 3323 kfree(var_hist); 3324 return ERR_PTR(-ENOMEM); 3325 } 3326 3327 /* Use the same keys as the compatible histogram */ 3328 strcat(cmd, "keys="); 3329 3330 for_each_hist_key_field(i, hist_data) { 3331 key_field = hist_data->fields[i]; 3332 if (!first) 3333 strcat(cmd, ","); 3334 strcat(cmd, key_field->field->name); 3335 first = false; 3336 } 3337 3338 /* Create the synthetic field variable specification */ 3339 strcat(cmd, ":synthetic_"); 3340 strcat(cmd, field_name); 3341 strcat(cmd, "="); 3342 strcat(cmd, field_name); 3343 3344 /* Use the same filter as the compatible histogram */ 3345 saved_filter = find_trigger_filter(hist_data, file); 3346 if (saved_filter) { 3347 strcat(cmd, " if "); 3348 strcat(cmd, saved_filter); 3349 } 3350 3351 var_hist->cmd = kstrdup(cmd, GFP_KERNEL); 3352 if (!var_hist->cmd) { 3353 kfree(cmd); 3354 kfree(var_hist); 3355 return ERR_PTR(-ENOMEM); 3356 } 3357 3358 /* Save the compatible histogram information */ 3359 var_hist->hist_data = hist_data; 3360 3361 /* Create the new histogram with our variable */ 3362 ret = event_hist_trigger_func(&trigger_hist_cmd, file, 3363 "", "hist", cmd); 3364 if (ret) { 3365 kfree(cmd); 3366 kfree(var_hist->cmd); 3367 kfree(var_hist); 3368 hist_err(tr, HIST_ERR_HIST_CREATE_FAIL, errpos(field_name)); 3369 return ERR_PTR(ret); 3370 } 3371 3372 kfree(cmd); 3373 3374 /* If we can't find the variable, something went wrong */ 3375 event_var = find_synthetic_field_var(target_hist_data, subsys_name, 3376 event_name, field_name); 3377 if (IS_ERR_OR_NULL(event_var)) { 3378 kfree(var_hist->cmd); 3379 kfree(var_hist); 3380 hist_err(tr, HIST_ERR_SYNTH_VAR_NOT_FOUND, errpos(field_name)); 3381 return ERR_PTR(-EINVAL); 3382 } 3383 3384 n = target_hist_data->n_field_var_hists; 3385 target_hist_data->field_var_hists[n] = var_hist; 3386 target_hist_data->n_field_var_hists++; 3387 3388 return event_var; 3389 } 3390 3391 static struct hist_field * 3392 find_target_event_var(struct hist_trigger_data *hist_data, 3393 char *subsys_name, char *event_name, char *var_name) 3394 { 3395 struct trace_event_file *file = hist_data->event_file; 3396 struct hist_field *hist_field = NULL; 3397 3398 if (subsys_name) { 3399 struct trace_event_call *call; 3400 3401 if (!event_name) 3402 return NULL; 3403 3404 call = file->event_call; 3405 3406 if (strcmp(subsys_name, call->class->system) != 0) 3407 return NULL; 3408 3409 if (strcmp(event_name, trace_event_name(call)) != 0) 3410 return NULL; 3411 } 3412 3413 hist_field = find_var_field(hist_data, var_name); 3414 3415 return hist_field; 3416 } 3417 3418 static inline void __update_field_vars(struct tracing_map_elt *elt, 3419 struct ring_buffer_event *rbe, 3420 void *rec, 3421 struct field_var **field_vars, 3422 unsigned int n_field_vars, 3423 unsigned int field_var_str_start) 3424 { 3425 struct hist_elt_data *elt_data = elt->private_data; 3426 unsigned int i, j, var_idx; 3427 u64 var_val; 3428 3429 for (i = 0, j = field_var_str_start; i < n_field_vars; i++) { 3430 struct field_var *field_var = field_vars[i]; 3431 struct hist_field *var = field_var->var; 3432 struct hist_field *val = field_var->val; 3433 3434 var_val = val->fn(val, elt, rbe, rec); 3435 var_idx = var->var.idx; 3436 3437 if (val->flags & HIST_FIELD_FL_STRING) { 3438 char *str = elt_data->field_var_str[j++]; 3439 char *val_str = (char *)(uintptr_t)var_val; 3440 3441 strscpy(str, val_str, STR_VAR_LEN_MAX); 3442 var_val = (u64)(uintptr_t)str; 3443 } 3444 tracing_map_set_var(elt, var_idx, var_val); 3445 } 3446 } 3447 3448 static void update_field_vars(struct hist_trigger_data *hist_data, 3449 struct tracing_map_elt *elt, 3450 struct ring_buffer_event *rbe, 3451 void *rec) 3452 { 3453 __update_field_vars(elt, rbe, rec, hist_data->field_vars, 3454 hist_data->n_field_vars, 0); 3455 } 3456 3457 static void save_track_data_vars(struct hist_trigger_data *hist_data, 3458 struct tracing_map_elt *elt, void *rec, 3459 struct ring_buffer_event *rbe, void *key, 3460 struct action_data *data, u64 *var_ref_vals) 3461 { 3462 __update_field_vars(elt, rbe, rec, hist_data->save_vars, 3463 hist_data->n_save_vars, hist_data->n_field_var_str); 3464 } 3465 3466 static struct hist_field *create_var(struct hist_trigger_data *hist_data, 3467 struct trace_event_file *file, 3468 char *name, int size, const char *type) 3469 { 3470 struct hist_field *var; 3471 int idx; 3472 3473 if (find_var(hist_data, file, name) && !hist_data->remove) { 3474 var = ERR_PTR(-EINVAL); 3475 goto out; 3476 } 3477 3478 var = kzalloc(sizeof(struct hist_field), GFP_KERNEL); 3479 if (!var) { 3480 var = ERR_PTR(-ENOMEM); 3481 goto out; 3482 } 3483 3484 idx = tracing_map_add_var(hist_data->map); 3485 if (idx < 0) { 3486 kfree(var); 3487 var = ERR_PTR(-EINVAL); 3488 goto out; 3489 } 3490 3491 var->flags = HIST_FIELD_FL_VAR; 3492 var->var.idx = idx; 3493 var->var.hist_data = var->hist_data = hist_data; 3494 var->size = size; 3495 var->var.name = kstrdup(name, GFP_KERNEL); 3496 var->type = kstrdup(type, GFP_KERNEL); 3497 if (!var->var.name || !var->type) { 3498 kfree(var->var.name); 3499 kfree(var->type); 3500 kfree(var); 3501 var = ERR_PTR(-ENOMEM); 3502 } 3503 out: 3504 return var; 3505 } 3506 3507 static struct field_var *create_field_var(struct hist_trigger_data *hist_data, 3508 struct trace_event_file *file, 3509 char *field_name) 3510 { 3511 struct hist_field *val = NULL, *var = NULL; 3512 unsigned long flags = HIST_FIELD_FL_VAR; 3513 struct trace_array *tr = file->tr; 3514 struct field_var *field_var; 3515 int ret = 0; 3516 3517 if (hist_data->n_field_vars >= SYNTH_FIELDS_MAX) { 3518 hist_err(tr, HIST_ERR_TOO_MANY_FIELD_VARS, errpos(field_name)); 3519 ret = -EINVAL; 3520 goto err; 3521 } 3522 3523 val = parse_atom(hist_data, file, field_name, &flags, NULL); 3524 if (IS_ERR(val)) { 3525 hist_err(tr, HIST_ERR_FIELD_VAR_PARSE_FAIL, errpos(field_name)); 3526 ret = PTR_ERR(val); 3527 goto err; 3528 } 3529 3530 var = create_var(hist_data, file, field_name, val->size, val->type); 3531 if (IS_ERR(var)) { 3532 hist_err(tr, HIST_ERR_VAR_CREATE_FIND_FAIL, errpos(field_name)); 3533 kfree(val); 3534 ret = PTR_ERR(var); 3535 goto err; 3536 } 3537 3538 field_var = kzalloc(sizeof(struct field_var), GFP_KERNEL); 3539 if (!field_var) { 3540 kfree(val); 3541 kfree(var); 3542 ret = -ENOMEM; 3543 goto err; 3544 } 3545 3546 field_var->var = var; 3547 field_var->val = val; 3548 out: 3549 return field_var; 3550 err: 3551 field_var = ERR_PTR(ret); 3552 goto out; 3553 } 3554 3555 /** 3556 * create_target_field_var - Automatically create a variable for a field 3557 * @target_hist_data: The target hist trigger 3558 * @subsys_name: Optional subsystem name 3559 * @event_name: Optional event name 3560 * @var_name: The name of the field (and the resulting variable) 3561 * 3562 * Hist trigger actions fetch data from variables, not directly from 3563 * events. However, for convenience, users are allowed to directly 3564 * specify an event field in an action, which will be automatically 3565 * converted into a variable on their behalf. 3566 3567 * This function creates a field variable with the name var_name on 3568 * the hist trigger currently being defined on the target event. If 3569 * subsys_name and event_name are specified, this function simply 3570 * verifies that they do in fact match the target event subsystem and 3571 * event name. 3572 * 3573 * Return: The variable created for the field. 3574 */ 3575 static struct field_var * 3576 create_target_field_var(struct hist_trigger_data *target_hist_data, 3577 char *subsys_name, char *event_name, char *var_name) 3578 { 3579 struct trace_event_file *file = target_hist_data->event_file; 3580 3581 if (subsys_name) { 3582 struct trace_event_call *call; 3583 3584 if (!event_name) 3585 return NULL; 3586 3587 call = file->event_call; 3588 3589 if (strcmp(subsys_name, call->class->system) != 0) 3590 return NULL; 3591 3592 if (strcmp(event_name, trace_event_name(call)) != 0) 3593 return NULL; 3594 } 3595 3596 return create_field_var(target_hist_data, file, var_name); 3597 } 3598 3599 static bool check_track_val_max(u64 track_val, u64 var_val) 3600 { 3601 if (var_val <= track_val) 3602 return false; 3603 3604 return true; 3605 } 3606 3607 static bool check_track_val_changed(u64 track_val, u64 var_val) 3608 { 3609 if (var_val == track_val) 3610 return false; 3611 3612 return true; 3613 } 3614 3615 static u64 get_track_val(struct hist_trigger_data *hist_data, 3616 struct tracing_map_elt *elt, 3617 struct action_data *data) 3618 { 3619 unsigned int track_var_idx = data->track_data.track_var->var.idx; 3620 u64 track_val; 3621 3622 track_val = tracing_map_read_var(elt, track_var_idx); 3623 3624 return track_val; 3625 } 3626 3627 static void save_track_val(struct hist_trigger_data *hist_data, 3628 struct tracing_map_elt *elt, 3629 struct action_data *data, u64 var_val) 3630 { 3631 unsigned int track_var_idx = data->track_data.track_var->var.idx; 3632 3633 tracing_map_set_var(elt, track_var_idx, var_val); 3634 } 3635 3636 static void save_track_data(struct hist_trigger_data *hist_data, 3637 struct tracing_map_elt *elt, void *rec, 3638 struct ring_buffer_event *rbe, void *key, 3639 struct action_data *data, u64 *var_ref_vals) 3640 { 3641 if (data->track_data.save_data) 3642 data->track_data.save_data(hist_data, elt, rec, rbe, key, data, var_ref_vals); 3643 } 3644 3645 static bool check_track_val(struct tracing_map_elt *elt, 3646 struct action_data *data, 3647 u64 var_val) 3648 { 3649 struct hist_trigger_data *hist_data; 3650 u64 track_val; 3651 3652 hist_data = data->track_data.track_var->hist_data; 3653 track_val = get_track_val(hist_data, elt, data); 3654 3655 return data->track_data.check_val(track_val, var_val); 3656 } 3657 3658 #ifdef CONFIG_TRACER_SNAPSHOT 3659 static bool cond_snapshot_update(struct trace_array *tr, void *cond_data) 3660 { 3661 /* called with tr->max_lock held */ 3662 struct track_data *track_data = tr->cond_snapshot->cond_data; 3663 struct hist_elt_data *elt_data, *track_elt_data; 3664 struct snapshot_context *context = cond_data; 3665 struct action_data *action; 3666 u64 track_val; 3667 3668 if (!track_data) 3669 return false; 3670 3671 action = track_data->action_data; 3672 3673 track_val = get_track_val(track_data->hist_data, context->elt, 3674 track_data->action_data); 3675 3676 if (!action->track_data.check_val(track_data->track_val, track_val)) 3677 return false; 3678 3679 track_data->track_val = track_val; 3680 memcpy(track_data->key, context->key, track_data->key_len); 3681 3682 elt_data = context->elt->private_data; 3683 track_elt_data = track_data->elt.private_data; 3684 if (elt_data->comm) 3685 strncpy(track_elt_data->comm, elt_data->comm, TASK_COMM_LEN); 3686 3687 track_data->updated = true; 3688 3689 return true; 3690 } 3691 3692 static void save_track_data_snapshot(struct hist_trigger_data *hist_data, 3693 struct tracing_map_elt *elt, void *rec, 3694 struct ring_buffer_event *rbe, void *key, 3695 struct action_data *data, 3696 u64 *var_ref_vals) 3697 { 3698 struct trace_event_file *file = hist_data->event_file; 3699 struct snapshot_context context; 3700 3701 context.elt = elt; 3702 context.key = key; 3703 3704 tracing_snapshot_cond(file->tr, &context); 3705 } 3706 3707 static void hist_trigger_print_key(struct seq_file *m, 3708 struct hist_trigger_data *hist_data, 3709 void *key, 3710 struct tracing_map_elt *elt); 3711 3712 static struct action_data *snapshot_action(struct hist_trigger_data *hist_data) 3713 { 3714 unsigned int i; 3715 3716 if (!hist_data->n_actions) 3717 return NULL; 3718 3719 for (i = 0; i < hist_data->n_actions; i++) { 3720 struct action_data *data = hist_data->actions[i]; 3721 3722 if (data->action == ACTION_SNAPSHOT) 3723 return data; 3724 } 3725 3726 return NULL; 3727 } 3728 3729 static void track_data_snapshot_print(struct seq_file *m, 3730 struct hist_trigger_data *hist_data) 3731 { 3732 struct trace_event_file *file = hist_data->event_file; 3733 struct track_data *track_data; 3734 struct action_data *action; 3735 3736 track_data = tracing_cond_snapshot_data(file->tr); 3737 if (!track_data) 3738 return; 3739 3740 if (!track_data->updated) 3741 return; 3742 3743 action = snapshot_action(hist_data); 3744 if (!action) 3745 return; 3746 3747 seq_puts(m, "\nSnapshot taken (see tracing/snapshot). Details:\n"); 3748 seq_printf(m, "\ttriggering value { %s(%s) }: %10llu", 3749 action->handler == HANDLER_ONMAX ? "onmax" : "onchange", 3750 action->track_data.var_str, track_data->track_val); 3751 3752 seq_puts(m, "\ttriggered by event with key: "); 3753 hist_trigger_print_key(m, hist_data, track_data->key, &track_data->elt); 3754 seq_putc(m, '\n'); 3755 } 3756 #else 3757 static bool cond_snapshot_update(struct trace_array *tr, void *cond_data) 3758 { 3759 return false; 3760 } 3761 static void save_track_data_snapshot(struct hist_trigger_data *hist_data, 3762 struct tracing_map_elt *elt, void *rec, 3763 struct ring_buffer_event *rbe, void *key, 3764 struct action_data *data, 3765 u64 *var_ref_vals) {} 3766 static void track_data_snapshot_print(struct seq_file *m, 3767 struct hist_trigger_data *hist_data) {} 3768 #endif /* CONFIG_TRACER_SNAPSHOT */ 3769 3770 static void track_data_print(struct seq_file *m, 3771 struct hist_trigger_data *hist_data, 3772 struct tracing_map_elt *elt, 3773 struct action_data *data) 3774 { 3775 u64 track_val = get_track_val(hist_data, elt, data); 3776 unsigned int i, save_var_idx; 3777 3778 if (data->handler == HANDLER_ONMAX) 3779 seq_printf(m, "\n\tmax: %10llu", track_val); 3780 else if (data->handler == HANDLER_ONCHANGE) 3781 seq_printf(m, "\n\tchanged: %10llu", track_val); 3782 3783 if (data->action == ACTION_SNAPSHOT) 3784 return; 3785 3786 for (i = 0; i < hist_data->n_save_vars; i++) { 3787 struct hist_field *save_val = hist_data->save_vars[i]->val; 3788 struct hist_field *save_var = hist_data->save_vars[i]->var; 3789 u64 val; 3790 3791 save_var_idx = save_var->var.idx; 3792 3793 val = tracing_map_read_var(elt, save_var_idx); 3794 3795 if (save_val->flags & HIST_FIELD_FL_STRING) { 3796 seq_printf(m, " %s: %-32s", save_var->var.name, 3797 (char *)(uintptr_t)(val)); 3798 } else 3799 seq_printf(m, " %s: %10llu", save_var->var.name, val); 3800 } 3801 } 3802 3803 static void ontrack_action(struct hist_trigger_data *hist_data, 3804 struct tracing_map_elt *elt, void *rec, 3805 struct ring_buffer_event *rbe, void *key, 3806 struct action_data *data, u64 *var_ref_vals) 3807 { 3808 u64 var_val = var_ref_vals[data->track_data.var_ref->var_ref_idx]; 3809 3810 if (check_track_val(elt, data, var_val)) { 3811 save_track_val(hist_data, elt, data, var_val); 3812 save_track_data(hist_data, elt, rec, rbe, key, data, var_ref_vals); 3813 } 3814 } 3815 3816 static void action_data_destroy(struct action_data *data) 3817 { 3818 unsigned int i; 3819 3820 lockdep_assert_held(&event_mutex); 3821 3822 kfree(data->action_name); 3823 3824 for (i = 0; i < data->n_params; i++) 3825 kfree(data->params[i]); 3826 3827 if (data->synth_event) 3828 data->synth_event->ref--; 3829 3830 kfree(data->synth_event_name); 3831 3832 kfree(data); 3833 } 3834 3835 static void track_data_destroy(struct hist_trigger_data *hist_data, 3836 struct action_data *data) 3837 { 3838 struct trace_event_file *file = hist_data->event_file; 3839 3840 destroy_hist_field(data->track_data.track_var, 0); 3841 3842 if (data->action == ACTION_SNAPSHOT) { 3843 struct track_data *track_data; 3844 3845 track_data = tracing_cond_snapshot_data(file->tr); 3846 if (track_data && track_data->hist_data == hist_data) { 3847 tracing_snapshot_cond_disable(file->tr); 3848 track_data_free(track_data); 3849 } 3850 } 3851 3852 kfree(data->track_data.var_str); 3853 3854 action_data_destroy(data); 3855 } 3856 3857 static int action_create(struct hist_trigger_data *hist_data, 3858 struct action_data *data); 3859 3860 static int track_data_create(struct hist_trigger_data *hist_data, 3861 struct action_data *data) 3862 { 3863 struct hist_field *var_field, *ref_field, *track_var = NULL; 3864 struct trace_event_file *file = hist_data->event_file; 3865 struct trace_array *tr = file->tr; 3866 char *track_data_var_str; 3867 int ret = 0; 3868 3869 track_data_var_str = data->track_data.var_str; 3870 if (track_data_var_str[0] != '$') { 3871 hist_err(tr, HIST_ERR_ONX_NOT_VAR, errpos(track_data_var_str)); 3872 return -EINVAL; 3873 } 3874 track_data_var_str++; 3875 3876 var_field = find_target_event_var(hist_data, NULL, NULL, track_data_var_str); 3877 if (!var_field) { 3878 hist_err(tr, HIST_ERR_ONX_VAR_NOT_FOUND, errpos(track_data_var_str)); 3879 return -EINVAL; 3880 } 3881 3882 ref_field = create_var_ref(hist_data, var_field, NULL, NULL); 3883 if (!ref_field) 3884 return -ENOMEM; 3885 3886 data->track_data.var_ref = ref_field; 3887 3888 if (data->handler == HANDLER_ONMAX) 3889 track_var = create_var(hist_data, file, "__max", sizeof(u64), "u64"); 3890 if (IS_ERR(track_var)) { 3891 hist_err(tr, HIST_ERR_ONX_VAR_CREATE_FAIL, 0); 3892 ret = PTR_ERR(track_var); 3893 goto out; 3894 } 3895 3896 if (data->handler == HANDLER_ONCHANGE) 3897 track_var = create_var(hist_data, file, "__change", sizeof(u64), "u64"); 3898 if (IS_ERR(track_var)) { 3899 hist_err(tr, HIST_ERR_ONX_VAR_CREATE_FAIL, 0); 3900 ret = PTR_ERR(track_var); 3901 goto out; 3902 } 3903 data->track_data.track_var = track_var; 3904 3905 ret = action_create(hist_data, data); 3906 out: 3907 return ret; 3908 } 3909 3910 static int parse_action_params(struct trace_array *tr, char *params, 3911 struct action_data *data) 3912 { 3913 char *param, *saved_param; 3914 bool first_param = true; 3915 int ret = 0; 3916 3917 while (params) { 3918 if (data->n_params >= SYNTH_FIELDS_MAX) { 3919 hist_err(tr, HIST_ERR_TOO_MANY_PARAMS, 0); 3920 goto out; 3921 } 3922 3923 param = strsep(¶ms, ","); 3924 if (!param) { 3925 hist_err(tr, HIST_ERR_PARAM_NOT_FOUND, 0); 3926 ret = -EINVAL; 3927 goto out; 3928 } 3929 3930 param = strstrip(param); 3931 if (strlen(param) < 2) { 3932 hist_err(tr, HIST_ERR_INVALID_PARAM, errpos(param)); 3933 ret = -EINVAL; 3934 goto out; 3935 } 3936 3937 saved_param = kstrdup(param, GFP_KERNEL); 3938 if (!saved_param) { 3939 ret = -ENOMEM; 3940 goto out; 3941 } 3942 3943 if (first_param && data->use_trace_keyword) { 3944 data->synth_event_name = saved_param; 3945 first_param = false; 3946 continue; 3947 } 3948 first_param = false; 3949 3950 data->params[data->n_params++] = saved_param; 3951 } 3952 out: 3953 return ret; 3954 } 3955 3956 static int action_parse(struct trace_array *tr, char *str, struct action_data *data, 3957 enum handler_id handler) 3958 { 3959 char *action_name; 3960 int ret = 0; 3961 3962 strsep(&str, "."); 3963 if (!str) { 3964 hist_err(tr, HIST_ERR_ACTION_NOT_FOUND, 0); 3965 ret = -EINVAL; 3966 goto out; 3967 } 3968 3969 action_name = strsep(&str, "("); 3970 if (!action_name || !str) { 3971 hist_err(tr, HIST_ERR_ACTION_NOT_FOUND, 0); 3972 ret = -EINVAL; 3973 goto out; 3974 } 3975 3976 if (str_has_prefix(action_name, "save")) { 3977 char *params = strsep(&str, ")"); 3978 3979 if (!params) { 3980 hist_err(tr, HIST_ERR_NO_SAVE_PARAMS, 0); 3981 ret = -EINVAL; 3982 goto out; 3983 } 3984 3985 ret = parse_action_params(tr, params, data); 3986 if (ret) 3987 goto out; 3988 3989 if (handler == HANDLER_ONMAX) 3990 data->track_data.check_val = check_track_val_max; 3991 else if (handler == HANDLER_ONCHANGE) 3992 data->track_data.check_val = check_track_val_changed; 3993 else { 3994 hist_err(tr, HIST_ERR_ACTION_MISMATCH, errpos(action_name)); 3995 ret = -EINVAL; 3996 goto out; 3997 } 3998 3999 data->track_data.save_data = save_track_data_vars; 4000 data->fn = ontrack_action; 4001 data->action = ACTION_SAVE; 4002 } else if (str_has_prefix(action_name, "snapshot")) { 4003 char *params = strsep(&str, ")"); 4004 4005 if (!str) { 4006 hist_err(tr, HIST_ERR_NO_CLOSING_PAREN, errpos(params)); 4007 ret = -EINVAL; 4008 goto out; 4009 } 4010 4011 if (handler == HANDLER_ONMAX) 4012 data->track_data.check_val = check_track_val_max; 4013 else if (handler == HANDLER_ONCHANGE) 4014 data->track_data.check_val = check_track_val_changed; 4015 else { 4016 hist_err(tr, HIST_ERR_ACTION_MISMATCH, errpos(action_name)); 4017 ret = -EINVAL; 4018 goto out; 4019 } 4020 4021 data->track_data.save_data = save_track_data_snapshot; 4022 data->fn = ontrack_action; 4023 data->action = ACTION_SNAPSHOT; 4024 } else { 4025 char *params = strsep(&str, ")"); 4026 4027 if (str_has_prefix(action_name, "trace")) 4028 data->use_trace_keyword = true; 4029 4030 if (params) { 4031 ret = parse_action_params(tr, params, data); 4032 if (ret) 4033 goto out; 4034 } 4035 4036 if (handler == HANDLER_ONMAX) 4037 data->track_data.check_val = check_track_val_max; 4038 else if (handler == HANDLER_ONCHANGE) 4039 data->track_data.check_val = check_track_val_changed; 4040 4041 if (handler != HANDLER_ONMATCH) { 4042 data->track_data.save_data = action_trace; 4043 data->fn = ontrack_action; 4044 } else 4045 data->fn = action_trace; 4046 4047 data->action = ACTION_TRACE; 4048 } 4049 4050 data->action_name = kstrdup(action_name, GFP_KERNEL); 4051 if (!data->action_name) { 4052 ret = -ENOMEM; 4053 goto out; 4054 } 4055 4056 data->handler = handler; 4057 out: 4058 return ret; 4059 } 4060 4061 static struct action_data *track_data_parse(struct hist_trigger_data *hist_data, 4062 char *str, enum handler_id handler) 4063 { 4064 struct action_data *data; 4065 int ret = -EINVAL; 4066 char *var_str; 4067 4068 data = kzalloc(sizeof(*data), GFP_KERNEL); 4069 if (!data) 4070 return ERR_PTR(-ENOMEM); 4071 4072 var_str = strsep(&str, ")"); 4073 if (!var_str || !str) { 4074 ret = -EINVAL; 4075 goto free; 4076 } 4077 4078 data->track_data.var_str = kstrdup(var_str, GFP_KERNEL); 4079 if (!data->track_data.var_str) { 4080 ret = -ENOMEM; 4081 goto free; 4082 } 4083 4084 ret = action_parse(hist_data->event_file->tr, str, data, handler); 4085 if (ret) 4086 goto free; 4087 out: 4088 return data; 4089 free: 4090 track_data_destroy(hist_data, data); 4091 data = ERR_PTR(ret); 4092 goto out; 4093 } 4094 4095 static void onmatch_destroy(struct action_data *data) 4096 { 4097 kfree(data->match_data.event); 4098 kfree(data->match_data.event_system); 4099 4100 action_data_destroy(data); 4101 } 4102 4103 static void destroy_field_var(struct field_var *field_var) 4104 { 4105 if (!field_var) 4106 return; 4107 4108 destroy_hist_field(field_var->var, 0); 4109 destroy_hist_field(field_var->val, 0); 4110 4111 kfree(field_var); 4112 } 4113 4114 static void destroy_field_vars(struct hist_trigger_data *hist_data) 4115 { 4116 unsigned int i; 4117 4118 for (i = 0; i < hist_data->n_field_vars; i++) 4119 destroy_field_var(hist_data->field_vars[i]); 4120 } 4121 4122 static void save_field_var(struct hist_trigger_data *hist_data, 4123 struct field_var *field_var) 4124 { 4125 hist_data->field_vars[hist_data->n_field_vars++] = field_var; 4126 4127 if (field_var->val->flags & HIST_FIELD_FL_STRING) 4128 hist_data->n_field_var_str++; 4129 } 4130 4131 4132 static int check_synth_field(struct synth_event *event, 4133 struct hist_field *hist_field, 4134 unsigned int field_pos) 4135 { 4136 struct synth_field *field; 4137 4138 if (field_pos >= event->n_fields) 4139 return -EINVAL; 4140 4141 field = event->fields[field_pos]; 4142 4143 if (strcmp(field->type, hist_field->type) != 0) 4144 return -EINVAL; 4145 4146 return 0; 4147 } 4148 4149 static struct hist_field * 4150 trace_action_find_var(struct hist_trigger_data *hist_data, 4151 struct action_data *data, 4152 char *system, char *event, char *var) 4153 { 4154 struct trace_array *tr = hist_data->event_file->tr; 4155 struct hist_field *hist_field; 4156 4157 var++; /* skip '$' */ 4158 4159 hist_field = find_target_event_var(hist_data, system, event, var); 4160 if (!hist_field) { 4161 if (!system && data->handler == HANDLER_ONMATCH) { 4162 system = data->match_data.event_system; 4163 event = data->match_data.event; 4164 } 4165 4166 hist_field = find_event_var(hist_data, system, event, var); 4167 } 4168 4169 if (!hist_field) 4170 hist_err(tr, HIST_ERR_PARAM_NOT_FOUND, errpos(var)); 4171 4172 return hist_field; 4173 } 4174 4175 static struct hist_field * 4176 trace_action_create_field_var(struct hist_trigger_data *hist_data, 4177 struct action_data *data, char *system, 4178 char *event, char *var) 4179 { 4180 struct hist_field *hist_field = NULL; 4181 struct field_var *field_var; 4182 4183 /* 4184 * First try to create a field var on the target event (the 4185 * currently being defined). This will create a variable for 4186 * unqualified fields on the target event, or if qualified, 4187 * target fields that have qualified names matching the target. 4188 */ 4189 field_var = create_target_field_var(hist_data, system, event, var); 4190 4191 if (field_var && !IS_ERR(field_var)) { 4192 save_field_var(hist_data, field_var); 4193 hist_field = field_var->var; 4194 } else { 4195 field_var = NULL; 4196 /* 4197 * If no explicit system.event is specfied, default to 4198 * looking for fields on the onmatch(system.event.xxx) 4199 * event. 4200 */ 4201 if (!system && data->handler == HANDLER_ONMATCH) { 4202 system = data->match_data.event_system; 4203 event = data->match_data.event; 4204 } 4205 4206 /* 4207 * At this point, we're looking at a field on another 4208 * event. Because we can't modify a hist trigger on 4209 * another event to add a variable for a field, we need 4210 * to create a new trigger on that event and create the 4211 * variable at the same time. 4212 */ 4213 hist_field = create_field_var_hist(hist_data, system, event, var); 4214 if (IS_ERR(hist_field)) 4215 goto free; 4216 } 4217 out: 4218 return hist_field; 4219 free: 4220 destroy_field_var(field_var); 4221 hist_field = NULL; 4222 goto out; 4223 } 4224 4225 static int trace_action_create(struct hist_trigger_data *hist_data, 4226 struct action_data *data) 4227 { 4228 struct trace_array *tr = hist_data->event_file->tr; 4229 char *event_name, *param, *system = NULL; 4230 struct hist_field *hist_field, *var_ref; 4231 unsigned int i, var_ref_idx; 4232 unsigned int field_pos = 0; 4233 struct synth_event *event; 4234 char *synth_event_name; 4235 int ret = 0; 4236 4237 lockdep_assert_held(&event_mutex); 4238 4239 if (data->use_trace_keyword) 4240 synth_event_name = data->synth_event_name; 4241 else 4242 synth_event_name = data->action_name; 4243 4244 event = find_synth_event(synth_event_name); 4245 if (!event) { 4246 hist_err(tr, HIST_ERR_SYNTH_EVENT_NOT_FOUND, errpos(synth_event_name)); 4247 return -EINVAL; 4248 } 4249 4250 event->ref++; 4251 4252 var_ref_idx = hist_data->n_var_refs; 4253 4254 for (i = 0; i < data->n_params; i++) { 4255 char *p; 4256 4257 p = param = kstrdup(data->params[i], GFP_KERNEL); 4258 if (!param) { 4259 ret = -ENOMEM; 4260 goto err; 4261 } 4262 4263 system = strsep(¶m, "."); 4264 if (!param) { 4265 param = (char *)system; 4266 system = event_name = NULL; 4267 } else { 4268 event_name = strsep(¶m, "."); 4269 if (!param) { 4270 kfree(p); 4271 ret = -EINVAL; 4272 goto err; 4273 } 4274 } 4275 4276 if (param[0] == '$') 4277 hist_field = trace_action_find_var(hist_data, data, 4278 system, event_name, 4279 param); 4280 else 4281 hist_field = trace_action_create_field_var(hist_data, 4282 data, 4283 system, 4284 event_name, 4285 param); 4286 4287 if (!hist_field) { 4288 kfree(p); 4289 ret = -EINVAL; 4290 goto err; 4291 } 4292 4293 if (check_synth_field(event, hist_field, field_pos) == 0) { 4294 var_ref = create_var_ref(hist_data, hist_field, 4295 system, event_name); 4296 if (!var_ref) { 4297 kfree(p); 4298 ret = -ENOMEM; 4299 goto err; 4300 } 4301 4302 field_pos++; 4303 kfree(p); 4304 continue; 4305 } 4306 4307 hist_err(tr, HIST_ERR_SYNTH_TYPE_MISMATCH, errpos(param)); 4308 kfree(p); 4309 ret = -EINVAL; 4310 goto err; 4311 } 4312 4313 if (field_pos != event->n_fields) { 4314 hist_err(tr, HIST_ERR_SYNTH_COUNT_MISMATCH, errpos(event->name)); 4315 ret = -EINVAL; 4316 goto err; 4317 } 4318 4319 data->synth_event = event; 4320 data->var_ref_idx = var_ref_idx; 4321 out: 4322 return ret; 4323 err: 4324 event->ref--; 4325 4326 goto out; 4327 } 4328 4329 static int action_create(struct hist_trigger_data *hist_data, 4330 struct action_data *data) 4331 { 4332 struct trace_event_file *file = hist_data->event_file; 4333 struct trace_array *tr = file->tr; 4334 struct track_data *track_data; 4335 struct field_var *field_var; 4336 unsigned int i; 4337 char *param; 4338 int ret = 0; 4339 4340 if (data->action == ACTION_TRACE) 4341 return trace_action_create(hist_data, data); 4342 4343 if (data->action == ACTION_SNAPSHOT) { 4344 track_data = track_data_alloc(hist_data->key_size, data, hist_data); 4345 if (IS_ERR(track_data)) { 4346 ret = PTR_ERR(track_data); 4347 goto out; 4348 } 4349 4350 ret = tracing_snapshot_cond_enable(file->tr, track_data, 4351 cond_snapshot_update); 4352 if (ret) 4353 track_data_free(track_data); 4354 4355 goto out; 4356 } 4357 4358 if (data->action == ACTION_SAVE) { 4359 if (hist_data->n_save_vars) { 4360 ret = -EEXIST; 4361 hist_err(tr, HIST_ERR_TOO_MANY_SAVE_ACTIONS, 0); 4362 goto out; 4363 } 4364 4365 for (i = 0; i < data->n_params; i++) { 4366 param = kstrdup(data->params[i], GFP_KERNEL); 4367 if (!param) { 4368 ret = -ENOMEM; 4369 goto out; 4370 } 4371 4372 field_var = create_target_field_var(hist_data, NULL, NULL, param); 4373 if (IS_ERR(field_var)) { 4374 hist_err(tr, HIST_ERR_FIELD_VAR_CREATE_FAIL, 4375 errpos(param)); 4376 ret = PTR_ERR(field_var); 4377 kfree(param); 4378 goto out; 4379 } 4380 4381 hist_data->save_vars[hist_data->n_save_vars++] = field_var; 4382 if (field_var->val->flags & HIST_FIELD_FL_STRING) 4383 hist_data->n_save_var_str++; 4384 kfree(param); 4385 } 4386 } 4387 out: 4388 return ret; 4389 } 4390 4391 static int onmatch_create(struct hist_trigger_data *hist_data, 4392 struct action_data *data) 4393 { 4394 return action_create(hist_data, data); 4395 } 4396 4397 static struct action_data *onmatch_parse(struct trace_array *tr, char *str) 4398 { 4399 char *match_event, *match_event_system; 4400 struct action_data *data; 4401 int ret = -EINVAL; 4402 4403 data = kzalloc(sizeof(*data), GFP_KERNEL); 4404 if (!data) 4405 return ERR_PTR(-ENOMEM); 4406 4407 match_event = strsep(&str, ")"); 4408 if (!match_event || !str) { 4409 hist_err(tr, HIST_ERR_NO_CLOSING_PAREN, errpos(match_event)); 4410 goto free; 4411 } 4412 4413 match_event_system = strsep(&match_event, "."); 4414 if (!match_event) { 4415 hist_err(tr, HIST_ERR_SUBSYS_NOT_FOUND, errpos(match_event_system)); 4416 goto free; 4417 } 4418 4419 if (IS_ERR(event_file(tr, match_event_system, match_event))) { 4420 hist_err(tr, HIST_ERR_INVALID_SUBSYS_EVENT, errpos(match_event)); 4421 goto free; 4422 } 4423 4424 data->match_data.event = kstrdup(match_event, GFP_KERNEL); 4425 if (!data->match_data.event) { 4426 ret = -ENOMEM; 4427 goto free; 4428 } 4429 4430 data->match_data.event_system = kstrdup(match_event_system, GFP_KERNEL); 4431 if (!data->match_data.event_system) { 4432 ret = -ENOMEM; 4433 goto free; 4434 } 4435 4436 ret = action_parse(tr, str, data, HANDLER_ONMATCH); 4437 if (ret) 4438 goto free; 4439 out: 4440 return data; 4441 free: 4442 onmatch_destroy(data); 4443 data = ERR_PTR(ret); 4444 goto out; 4445 } 4446 4447 static int create_hitcount_val(struct hist_trigger_data *hist_data) 4448 { 4449 hist_data->fields[HITCOUNT_IDX] = 4450 create_hist_field(hist_data, NULL, HIST_FIELD_FL_HITCOUNT, NULL); 4451 if (!hist_data->fields[HITCOUNT_IDX]) 4452 return -ENOMEM; 4453 4454 hist_data->n_vals++; 4455 hist_data->n_fields++; 4456 4457 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX)) 4458 return -EINVAL; 4459 4460 return 0; 4461 } 4462 4463 static int __create_val_field(struct hist_trigger_data *hist_data, 4464 unsigned int val_idx, 4465 struct trace_event_file *file, 4466 char *var_name, char *field_str, 4467 unsigned long flags) 4468 { 4469 struct hist_field *hist_field; 4470 int ret = 0; 4471 4472 hist_field = parse_expr(hist_data, file, field_str, flags, var_name, 0); 4473 if (IS_ERR(hist_field)) { 4474 ret = PTR_ERR(hist_field); 4475 goto out; 4476 } 4477 4478 hist_data->fields[val_idx] = hist_field; 4479 4480 ++hist_data->n_vals; 4481 ++hist_data->n_fields; 4482 4483 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX)) 4484 ret = -EINVAL; 4485 out: 4486 return ret; 4487 } 4488 4489 static int create_val_field(struct hist_trigger_data *hist_data, 4490 unsigned int val_idx, 4491 struct trace_event_file *file, 4492 char *field_str) 4493 { 4494 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX)) 4495 return -EINVAL; 4496 4497 return __create_val_field(hist_data, val_idx, file, NULL, field_str, 0); 4498 } 4499 4500 static int create_var_field(struct hist_trigger_data *hist_data, 4501 unsigned int val_idx, 4502 struct trace_event_file *file, 4503 char *var_name, char *expr_str) 4504 { 4505 struct trace_array *tr = hist_data->event_file->tr; 4506 unsigned long flags = 0; 4507 4508 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX)) 4509 return -EINVAL; 4510 4511 if (find_var(hist_data, file, var_name) && !hist_data->remove) { 4512 hist_err(tr, HIST_ERR_DUPLICATE_VAR, errpos(var_name)); 4513 return -EINVAL; 4514 } 4515 4516 flags |= HIST_FIELD_FL_VAR; 4517 hist_data->n_vars++; 4518 if (WARN_ON(hist_data->n_vars > TRACING_MAP_VARS_MAX)) 4519 return -EINVAL; 4520 4521 return __create_val_field(hist_data, val_idx, file, var_name, expr_str, flags); 4522 } 4523 4524 static int create_val_fields(struct hist_trigger_data *hist_data, 4525 struct trace_event_file *file) 4526 { 4527 char *fields_str, *field_str; 4528 unsigned int i, j = 1; 4529 int ret; 4530 4531 ret = create_hitcount_val(hist_data); 4532 if (ret) 4533 goto out; 4534 4535 fields_str = hist_data->attrs->vals_str; 4536 if (!fields_str) 4537 goto out; 4538 4539 strsep(&fields_str, "="); 4540 if (!fields_str) 4541 goto out; 4542 4543 for (i = 0, j = 1; i < TRACING_MAP_VALS_MAX && 4544 j < TRACING_MAP_VALS_MAX; i++) { 4545 field_str = strsep(&fields_str, ","); 4546 if (!field_str) 4547 break; 4548 4549 if (strcmp(field_str, "hitcount") == 0) 4550 continue; 4551 4552 ret = create_val_field(hist_data, j++, file, field_str); 4553 if (ret) 4554 goto out; 4555 } 4556 4557 if (fields_str && (strcmp(fields_str, "hitcount") != 0)) 4558 ret = -EINVAL; 4559 out: 4560 return ret; 4561 } 4562 4563 static int create_key_field(struct hist_trigger_data *hist_data, 4564 unsigned int key_idx, 4565 unsigned int key_offset, 4566 struct trace_event_file *file, 4567 char *field_str) 4568 { 4569 struct trace_array *tr = hist_data->event_file->tr; 4570 struct hist_field *hist_field = NULL; 4571 unsigned long flags = 0; 4572 unsigned int key_size; 4573 int ret = 0; 4574 4575 if (WARN_ON(key_idx >= HIST_FIELDS_MAX)) 4576 return -EINVAL; 4577 4578 flags |= HIST_FIELD_FL_KEY; 4579 4580 if (strcmp(field_str, "stacktrace") == 0) { 4581 flags |= HIST_FIELD_FL_STACKTRACE; 4582 key_size = sizeof(unsigned long) * HIST_STACKTRACE_DEPTH; 4583 hist_field = create_hist_field(hist_data, NULL, flags, NULL); 4584 } else { 4585 hist_field = parse_expr(hist_data, file, field_str, flags, 4586 NULL, 0); 4587 if (IS_ERR(hist_field)) { 4588 ret = PTR_ERR(hist_field); 4589 goto out; 4590 } 4591 4592 if (field_has_hist_vars(hist_field, 0)) { 4593 hist_err(tr, HIST_ERR_INVALID_REF_KEY, errpos(field_str)); 4594 destroy_hist_field(hist_field, 0); 4595 ret = -EINVAL; 4596 goto out; 4597 } 4598 4599 key_size = hist_field->size; 4600 } 4601 4602 hist_data->fields[key_idx] = hist_field; 4603 4604 key_size = ALIGN(key_size, sizeof(u64)); 4605 hist_data->fields[key_idx]->size = key_size; 4606 hist_data->fields[key_idx]->offset = key_offset; 4607 4608 hist_data->key_size += key_size; 4609 4610 if (hist_data->key_size > HIST_KEY_SIZE_MAX) { 4611 ret = -EINVAL; 4612 goto out; 4613 } 4614 4615 hist_data->n_keys++; 4616 hist_data->n_fields++; 4617 4618 if (WARN_ON(hist_data->n_keys > TRACING_MAP_KEYS_MAX)) 4619 return -EINVAL; 4620 4621 ret = key_size; 4622 out: 4623 return ret; 4624 } 4625 4626 static int create_key_fields(struct hist_trigger_data *hist_data, 4627 struct trace_event_file *file) 4628 { 4629 unsigned int i, key_offset = 0, n_vals = hist_data->n_vals; 4630 char *fields_str, *field_str; 4631 int ret = -EINVAL; 4632 4633 fields_str = hist_data->attrs->keys_str; 4634 if (!fields_str) 4635 goto out; 4636 4637 strsep(&fields_str, "="); 4638 if (!fields_str) 4639 goto out; 4640 4641 for (i = n_vals; i < n_vals + TRACING_MAP_KEYS_MAX; i++) { 4642 field_str = strsep(&fields_str, ","); 4643 if (!field_str) 4644 break; 4645 ret = create_key_field(hist_data, i, key_offset, 4646 file, field_str); 4647 if (ret < 0) 4648 goto out; 4649 key_offset += ret; 4650 } 4651 if (fields_str) { 4652 ret = -EINVAL; 4653 goto out; 4654 } 4655 ret = 0; 4656 out: 4657 return ret; 4658 } 4659 4660 static int create_var_fields(struct hist_trigger_data *hist_data, 4661 struct trace_event_file *file) 4662 { 4663 unsigned int i, j = hist_data->n_vals; 4664 int ret = 0; 4665 4666 unsigned int n_vars = hist_data->attrs->var_defs.n_vars; 4667 4668 for (i = 0; i < n_vars; i++) { 4669 char *var_name = hist_data->attrs->var_defs.name[i]; 4670 char *expr = hist_data->attrs->var_defs.expr[i]; 4671 4672 ret = create_var_field(hist_data, j++, file, var_name, expr); 4673 if (ret) 4674 goto out; 4675 } 4676 out: 4677 return ret; 4678 } 4679 4680 static void free_var_defs(struct hist_trigger_data *hist_data) 4681 { 4682 unsigned int i; 4683 4684 for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) { 4685 kfree(hist_data->attrs->var_defs.name[i]); 4686 kfree(hist_data->attrs->var_defs.expr[i]); 4687 } 4688 4689 hist_data->attrs->var_defs.n_vars = 0; 4690 } 4691 4692 static int parse_var_defs(struct hist_trigger_data *hist_data) 4693 { 4694 struct trace_array *tr = hist_data->event_file->tr; 4695 char *s, *str, *var_name, *field_str; 4696 unsigned int i, j, n_vars = 0; 4697 int ret = 0; 4698 4699 for (i = 0; i < hist_data->attrs->n_assignments; i++) { 4700 str = hist_data->attrs->assignment_str[i]; 4701 for (j = 0; j < TRACING_MAP_VARS_MAX; j++) { 4702 field_str = strsep(&str, ","); 4703 if (!field_str) 4704 break; 4705 4706 var_name = strsep(&field_str, "="); 4707 if (!var_name || !field_str) { 4708 hist_err(tr, HIST_ERR_MALFORMED_ASSIGNMENT, 4709 errpos(var_name)); 4710 ret = -EINVAL; 4711 goto free; 4712 } 4713 4714 if (n_vars == TRACING_MAP_VARS_MAX) { 4715 hist_err(tr, HIST_ERR_TOO_MANY_VARS, errpos(var_name)); 4716 ret = -EINVAL; 4717 goto free; 4718 } 4719 4720 s = kstrdup(var_name, GFP_KERNEL); 4721 if (!s) { 4722 ret = -ENOMEM; 4723 goto free; 4724 } 4725 hist_data->attrs->var_defs.name[n_vars] = s; 4726 4727 s = kstrdup(field_str, GFP_KERNEL); 4728 if (!s) { 4729 kfree(hist_data->attrs->var_defs.name[n_vars]); 4730 ret = -ENOMEM; 4731 goto free; 4732 } 4733 hist_data->attrs->var_defs.expr[n_vars++] = s; 4734 4735 hist_data->attrs->var_defs.n_vars = n_vars; 4736 } 4737 } 4738 4739 return ret; 4740 free: 4741 free_var_defs(hist_data); 4742 4743 return ret; 4744 } 4745 4746 static int create_hist_fields(struct hist_trigger_data *hist_data, 4747 struct trace_event_file *file) 4748 { 4749 int ret; 4750 4751 ret = parse_var_defs(hist_data); 4752 if (ret) 4753 goto out; 4754 4755 ret = create_val_fields(hist_data, file); 4756 if (ret) 4757 goto out; 4758 4759 ret = create_var_fields(hist_data, file); 4760 if (ret) 4761 goto out; 4762 4763 ret = create_key_fields(hist_data, file); 4764 if (ret) 4765 goto out; 4766 out: 4767 free_var_defs(hist_data); 4768 4769 return ret; 4770 } 4771 4772 static int is_descending(const char *str) 4773 { 4774 if (!str) 4775 return 0; 4776 4777 if (strcmp(str, "descending") == 0) 4778 return 1; 4779 4780 if (strcmp(str, "ascending") == 0) 4781 return 0; 4782 4783 return -EINVAL; 4784 } 4785 4786 static int create_sort_keys(struct hist_trigger_data *hist_data) 4787 { 4788 char *fields_str = hist_data->attrs->sort_key_str; 4789 struct tracing_map_sort_key *sort_key; 4790 int descending, ret = 0; 4791 unsigned int i, j, k; 4792 4793 hist_data->n_sort_keys = 1; /* we always have at least one, hitcount */ 4794 4795 if (!fields_str) 4796 goto out; 4797 4798 strsep(&fields_str, "="); 4799 if (!fields_str) { 4800 ret = -EINVAL; 4801 goto out; 4802 } 4803 4804 for (i = 0; i < TRACING_MAP_SORT_KEYS_MAX; i++) { 4805 struct hist_field *hist_field; 4806 char *field_str, *field_name; 4807 const char *test_name; 4808 4809 sort_key = &hist_data->sort_keys[i]; 4810 4811 field_str = strsep(&fields_str, ","); 4812 if (!field_str) { 4813 if (i == 0) 4814 ret = -EINVAL; 4815 break; 4816 } 4817 4818 if ((i == TRACING_MAP_SORT_KEYS_MAX - 1) && fields_str) { 4819 ret = -EINVAL; 4820 break; 4821 } 4822 4823 field_name = strsep(&field_str, "."); 4824 if (!field_name) { 4825 ret = -EINVAL; 4826 break; 4827 } 4828 4829 if (strcmp(field_name, "hitcount") == 0) { 4830 descending = is_descending(field_str); 4831 if (descending < 0) { 4832 ret = descending; 4833 break; 4834 } 4835 sort_key->descending = descending; 4836 continue; 4837 } 4838 4839 for (j = 1, k = 1; j < hist_data->n_fields; j++) { 4840 unsigned int idx; 4841 4842 hist_field = hist_data->fields[j]; 4843 if (hist_field->flags & HIST_FIELD_FL_VAR) 4844 continue; 4845 4846 idx = k++; 4847 4848 test_name = hist_field_name(hist_field, 0); 4849 4850 if (strcmp(field_name, test_name) == 0) { 4851 sort_key->field_idx = idx; 4852 descending = is_descending(field_str); 4853 if (descending < 0) { 4854 ret = descending; 4855 goto out; 4856 } 4857 sort_key->descending = descending; 4858 break; 4859 } 4860 } 4861 if (j == hist_data->n_fields) { 4862 ret = -EINVAL; 4863 break; 4864 } 4865 } 4866 4867 hist_data->n_sort_keys = i; 4868 out: 4869 return ret; 4870 } 4871 4872 static void destroy_actions(struct hist_trigger_data *hist_data) 4873 { 4874 unsigned int i; 4875 4876 for (i = 0; i < hist_data->n_actions; i++) { 4877 struct action_data *data = hist_data->actions[i]; 4878 4879 if (data->handler == HANDLER_ONMATCH) 4880 onmatch_destroy(data); 4881 else if (data->handler == HANDLER_ONMAX || 4882 data->handler == HANDLER_ONCHANGE) 4883 track_data_destroy(hist_data, data); 4884 else 4885 kfree(data); 4886 } 4887 } 4888 4889 static int parse_actions(struct hist_trigger_data *hist_data) 4890 { 4891 struct trace_array *tr = hist_data->event_file->tr; 4892 struct action_data *data; 4893 unsigned int i; 4894 int ret = 0; 4895 char *str; 4896 int len; 4897 4898 for (i = 0; i < hist_data->attrs->n_actions; i++) { 4899 str = hist_data->attrs->action_str[i]; 4900 4901 if ((len = str_has_prefix(str, "onmatch("))) { 4902 char *action_str = str + len; 4903 4904 data = onmatch_parse(tr, action_str); 4905 if (IS_ERR(data)) { 4906 ret = PTR_ERR(data); 4907 break; 4908 } 4909 } else if ((len = str_has_prefix(str, "onmax("))) { 4910 char *action_str = str + len; 4911 4912 data = track_data_parse(hist_data, action_str, 4913 HANDLER_ONMAX); 4914 if (IS_ERR(data)) { 4915 ret = PTR_ERR(data); 4916 break; 4917 } 4918 } else if ((len = str_has_prefix(str, "onchange("))) { 4919 char *action_str = str + len; 4920 4921 data = track_data_parse(hist_data, action_str, 4922 HANDLER_ONCHANGE); 4923 if (IS_ERR(data)) { 4924 ret = PTR_ERR(data); 4925 break; 4926 } 4927 } else { 4928 ret = -EINVAL; 4929 break; 4930 } 4931 4932 hist_data->actions[hist_data->n_actions++] = data; 4933 } 4934 4935 return ret; 4936 } 4937 4938 static int create_actions(struct hist_trigger_data *hist_data) 4939 { 4940 struct action_data *data; 4941 unsigned int i; 4942 int ret = 0; 4943 4944 for (i = 0; i < hist_data->attrs->n_actions; i++) { 4945 data = hist_data->actions[i]; 4946 4947 if (data->handler == HANDLER_ONMATCH) { 4948 ret = onmatch_create(hist_data, data); 4949 if (ret) 4950 break; 4951 } else if (data->handler == HANDLER_ONMAX || 4952 data->handler == HANDLER_ONCHANGE) { 4953 ret = track_data_create(hist_data, data); 4954 if (ret) 4955 break; 4956 } else { 4957 ret = -EINVAL; 4958 break; 4959 } 4960 } 4961 4962 return ret; 4963 } 4964 4965 static void print_actions(struct seq_file *m, 4966 struct hist_trigger_data *hist_data, 4967 struct tracing_map_elt *elt) 4968 { 4969 unsigned int i; 4970 4971 for (i = 0; i < hist_data->n_actions; i++) { 4972 struct action_data *data = hist_data->actions[i]; 4973 4974 if (data->action == ACTION_SNAPSHOT) 4975 continue; 4976 4977 if (data->handler == HANDLER_ONMAX || 4978 data->handler == HANDLER_ONCHANGE) 4979 track_data_print(m, hist_data, elt, data); 4980 } 4981 } 4982 4983 static void print_action_spec(struct seq_file *m, 4984 struct hist_trigger_data *hist_data, 4985 struct action_data *data) 4986 { 4987 unsigned int i; 4988 4989 if (data->action == ACTION_SAVE) { 4990 for (i = 0; i < hist_data->n_save_vars; i++) { 4991 seq_printf(m, "%s", hist_data->save_vars[i]->var->var.name); 4992 if (i < hist_data->n_save_vars - 1) 4993 seq_puts(m, ","); 4994 } 4995 } else if (data->action == ACTION_TRACE) { 4996 if (data->use_trace_keyword) 4997 seq_printf(m, "%s", data->synth_event_name); 4998 for (i = 0; i < data->n_params; i++) { 4999 if (i || data->use_trace_keyword) 5000 seq_puts(m, ","); 5001 seq_printf(m, "%s", data->params[i]); 5002 } 5003 } 5004 } 5005 5006 static void print_track_data_spec(struct seq_file *m, 5007 struct hist_trigger_data *hist_data, 5008 struct action_data *data) 5009 { 5010 if (data->handler == HANDLER_ONMAX) 5011 seq_puts(m, ":onmax("); 5012 else if (data->handler == HANDLER_ONCHANGE) 5013 seq_puts(m, ":onchange("); 5014 seq_printf(m, "%s", data->track_data.var_str); 5015 seq_printf(m, ").%s(", data->action_name); 5016 5017 print_action_spec(m, hist_data, data); 5018 5019 seq_puts(m, ")"); 5020 } 5021 5022 static void print_onmatch_spec(struct seq_file *m, 5023 struct hist_trigger_data *hist_data, 5024 struct action_data *data) 5025 { 5026 seq_printf(m, ":onmatch(%s.%s).", data->match_data.event_system, 5027 data->match_data.event); 5028 5029 seq_printf(m, "%s(", data->action_name); 5030 5031 print_action_spec(m, hist_data, data); 5032 5033 seq_puts(m, ")"); 5034 } 5035 5036 static bool actions_match(struct hist_trigger_data *hist_data, 5037 struct hist_trigger_data *hist_data_test) 5038 { 5039 unsigned int i, j; 5040 5041 if (hist_data->n_actions != hist_data_test->n_actions) 5042 return false; 5043 5044 for (i = 0; i < hist_data->n_actions; i++) { 5045 struct action_data *data = hist_data->actions[i]; 5046 struct action_data *data_test = hist_data_test->actions[i]; 5047 char *action_name, *action_name_test; 5048 5049 if (data->handler != data_test->handler) 5050 return false; 5051 if (data->action != data_test->action) 5052 return false; 5053 5054 if (data->n_params != data_test->n_params) 5055 return false; 5056 5057 for (j = 0; j < data->n_params; j++) { 5058 if (strcmp(data->params[j], data_test->params[j]) != 0) 5059 return false; 5060 } 5061 5062 if (data->use_trace_keyword) 5063 action_name = data->synth_event_name; 5064 else 5065 action_name = data->action_name; 5066 5067 if (data_test->use_trace_keyword) 5068 action_name_test = data_test->synth_event_name; 5069 else 5070 action_name_test = data_test->action_name; 5071 5072 if (strcmp(action_name, action_name_test) != 0) 5073 return false; 5074 5075 if (data->handler == HANDLER_ONMATCH) { 5076 if (strcmp(data->match_data.event_system, 5077 data_test->match_data.event_system) != 0) 5078 return false; 5079 if (strcmp(data->match_data.event, 5080 data_test->match_data.event) != 0) 5081 return false; 5082 } else if (data->handler == HANDLER_ONMAX || 5083 data->handler == HANDLER_ONCHANGE) { 5084 if (strcmp(data->track_data.var_str, 5085 data_test->track_data.var_str) != 0) 5086 return false; 5087 } 5088 } 5089 5090 return true; 5091 } 5092 5093 5094 static void print_actions_spec(struct seq_file *m, 5095 struct hist_trigger_data *hist_data) 5096 { 5097 unsigned int i; 5098 5099 for (i = 0; i < hist_data->n_actions; i++) { 5100 struct action_data *data = hist_data->actions[i]; 5101 5102 if (data->handler == HANDLER_ONMATCH) 5103 print_onmatch_spec(m, hist_data, data); 5104 else if (data->handler == HANDLER_ONMAX || 5105 data->handler == HANDLER_ONCHANGE) 5106 print_track_data_spec(m, hist_data, data); 5107 } 5108 } 5109 5110 static void destroy_field_var_hists(struct hist_trigger_data *hist_data) 5111 { 5112 unsigned int i; 5113 5114 for (i = 0; i < hist_data->n_field_var_hists; i++) { 5115 kfree(hist_data->field_var_hists[i]->cmd); 5116 kfree(hist_data->field_var_hists[i]); 5117 } 5118 } 5119 5120 static void destroy_hist_data(struct hist_trigger_data *hist_data) 5121 { 5122 if (!hist_data) 5123 return; 5124 5125 destroy_hist_trigger_attrs(hist_data->attrs); 5126 destroy_hist_fields(hist_data); 5127 tracing_map_destroy(hist_data->map); 5128 5129 destroy_actions(hist_data); 5130 destroy_field_vars(hist_data); 5131 destroy_field_var_hists(hist_data); 5132 5133 kfree(hist_data); 5134 } 5135 5136 static int create_tracing_map_fields(struct hist_trigger_data *hist_data) 5137 { 5138 struct tracing_map *map = hist_data->map; 5139 struct ftrace_event_field *field; 5140 struct hist_field *hist_field; 5141 int i, idx = 0; 5142 5143 for_each_hist_field(i, hist_data) { 5144 hist_field = hist_data->fields[i]; 5145 if (hist_field->flags & HIST_FIELD_FL_KEY) { 5146 tracing_map_cmp_fn_t cmp_fn; 5147 5148 field = hist_field->field; 5149 5150 if (hist_field->flags & HIST_FIELD_FL_STACKTRACE) 5151 cmp_fn = tracing_map_cmp_none; 5152 else if (!field) 5153 cmp_fn = tracing_map_cmp_num(hist_field->size, 5154 hist_field->is_signed); 5155 else if (is_string_field(field)) 5156 cmp_fn = tracing_map_cmp_string; 5157 else 5158 cmp_fn = tracing_map_cmp_num(field->size, 5159 field->is_signed); 5160 idx = tracing_map_add_key_field(map, 5161 hist_field->offset, 5162 cmp_fn); 5163 } else if (!(hist_field->flags & HIST_FIELD_FL_VAR)) 5164 idx = tracing_map_add_sum_field(map); 5165 5166 if (idx < 0) 5167 return idx; 5168 5169 if (hist_field->flags & HIST_FIELD_FL_VAR) { 5170 idx = tracing_map_add_var(map); 5171 if (idx < 0) 5172 return idx; 5173 hist_field->var.idx = idx; 5174 hist_field->var.hist_data = hist_data; 5175 } 5176 } 5177 5178 return 0; 5179 } 5180 5181 static struct hist_trigger_data * 5182 create_hist_data(unsigned int map_bits, 5183 struct hist_trigger_attrs *attrs, 5184 struct trace_event_file *file, 5185 bool remove) 5186 { 5187 const struct tracing_map_ops *map_ops = NULL; 5188 struct hist_trigger_data *hist_data; 5189 int ret = 0; 5190 5191 hist_data = kzalloc(sizeof(*hist_data), GFP_KERNEL); 5192 if (!hist_data) 5193 return ERR_PTR(-ENOMEM); 5194 5195 hist_data->attrs = attrs; 5196 hist_data->remove = remove; 5197 hist_data->event_file = file; 5198 5199 ret = parse_actions(hist_data); 5200 if (ret) 5201 goto free; 5202 5203 ret = create_hist_fields(hist_data, file); 5204 if (ret) 5205 goto free; 5206 5207 ret = create_sort_keys(hist_data); 5208 if (ret) 5209 goto free; 5210 5211 map_ops = &hist_trigger_elt_data_ops; 5212 5213 hist_data->map = tracing_map_create(map_bits, hist_data->key_size, 5214 map_ops, hist_data); 5215 if (IS_ERR(hist_data->map)) { 5216 ret = PTR_ERR(hist_data->map); 5217 hist_data->map = NULL; 5218 goto free; 5219 } 5220 5221 ret = create_tracing_map_fields(hist_data); 5222 if (ret) 5223 goto free; 5224 out: 5225 return hist_data; 5226 free: 5227 hist_data->attrs = NULL; 5228 5229 destroy_hist_data(hist_data); 5230 5231 hist_data = ERR_PTR(ret); 5232 5233 goto out; 5234 } 5235 5236 static void hist_trigger_elt_update(struct hist_trigger_data *hist_data, 5237 struct tracing_map_elt *elt, void *rec, 5238 struct ring_buffer_event *rbe, 5239 u64 *var_ref_vals) 5240 { 5241 struct hist_elt_data *elt_data; 5242 struct hist_field *hist_field; 5243 unsigned int i, var_idx; 5244 u64 hist_val; 5245 5246 elt_data = elt->private_data; 5247 elt_data->var_ref_vals = var_ref_vals; 5248 5249 for_each_hist_val_field(i, hist_data) { 5250 hist_field = hist_data->fields[i]; 5251 hist_val = hist_field->fn(hist_field, elt, rbe, rec); 5252 if (hist_field->flags & HIST_FIELD_FL_VAR) { 5253 var_idx = hist_field->var.idx; 5254 tracing_map_set_var(elt, var_idx, hist_val); 5255 continue; 5256 } 5257 tracing_map_update_sum(elt, i, hist_val); 5258 } 5259 5260 for_each_hist_key_field(i, hist_data) { 5261 hist_field = hist_data->fields[i]; 5262 if (hist_field->flags & HIST_FIELD_FL_VAR) { 5263 hist_val = hist_field->fn(hist_field, elt, rbe, rec); 5264 var_idx = hist_field->var.idx; 5265 tracing_map_set_var(elt, var_idx, hist_val); 5266 } 5267 } 5268 5269 update_field_vars(hist_data, elt, rbe, rec); 5270 } 5271 5272 static inline void add_to_key(char *compound_key, void *key, 5273 struct hist_field *key_field, void *rec) 5274 { 5275 size_t size = key_field->size; 5276 5277 if (key_field->flags & HIST_FIELD_FL_STRING) { 5278 struct ftrace_event_field *field; 5279 5280 field = key_field->field; 5281 if (field->filter_type == FILTER_DYN_STRING) 5282 size = *(u32 *)(rec + field->offset) >> 16; 5283 else if (field->filter_type == FILTER_PTR_STRING) 5284 size = strlen(key); 5285 else if (field->filter_type == FILTER_STATIC_STRING) 5286 size = field->size; 5287 5288 /* ensure NULL-termination */ 5289 if (size > key_field->size - 1) 5290 size = key_field->size - 1; 5291 5292 strncpy(compound_key + key_field->offset, (char *)key, size); 5293 } else 5294 memcpy(compound_key + key_field->offset, key, size); 5295 } 5296 5297 static void 5298 hist_trigger_actions(struct hist_trigger_data *hist_data, 5299 struct tracing_map_elt *elt, void *rec, 5300 struct ring_buffer_event *rbe, void *key, 5301 u64 *var_ref_vals) 5302 { 5303 struct action_data *data; 5304 unsigned int i; 5305 5306 for (i = 0; i < hist_data->n_actions; i++) { 5307 data = hist_data->actions[i]; 5308 data->fn(hist_data, elt, rec, rbe, key, data, var_ref_vals); 5309 } 5310 } 5311 5312 static void event_hist_trigger(struct event_trigger_data *data, void *rec, 5313 struct ring_buffer_event *rbe) 5314 { 5315 struct hist_trigger_data *hist_data = data->private_data; 5316 bool use_compound_key = (hist_data->n_keys > 1); 5317 unsigned long entries[HIST_STACKTRACE_DEPTH]; 5318 u64 var_ref_vals[TRACING_MAP_VARS_MAX]; 5319 char compound_key[HIST_KEY_SIZE_MAX]; 5320 struct tracing_map_elt *elt = NULL; 5321 struct hist_field *key_field; 5322 u64 field_contents; 5323 void *key = NULL; 5324 unsigned int i; 5325 5326 memset(compound_key, 0, hist_data->key_size); 5327 5328 for_each_hist_key_field(i, hist_data) { 5329 key_field = hist_data->fields[i]; 5330 5331 if (key_field->flags & HIST_FIELD_FL_STACKTRACE) { 5332 memset(entries, 0, HIST_STACKTRACE_SIZE); 5333 stack_trace_save(entries, HIST_STACKTRACE_DEPTH, 5334 HIST_STACKTRACE_SKIP); 5335 key = entries; 5336 } else { 5337 field_contents = key_field->fn(key_field, elt, rbe, rec); 5338 if (key_field->flags & HIST_FIELD_FL_STRING) { 5339 key = (void *)(unsigned long)field_contents; 5340 use_compound_key = true; 5341 } else 5342 key = (void *)&field_contents; 5343 } 5344 5345 if (use_compound_key) 5346 add_to_key(compound_key, key, key_field, rec); 5347 } 5348 5349 if (use_compound_key) 5350 key = compound_key; 5351 5352 if (hist_data->n_var_refs && 5353 !resolve_var_refs(hist_data, key, var_ref_vals, false)) 5354 return; 5355 5356 elt = tracing_map_insert(hist_data->map, key); 5357 if (!elt) 5358 return; 5359 5360 hist_trigger_elt_update(hist_data, elt, rec, rbe, var_ref_vals); 5361 5362 if (resolve_var_refs(hist_data, key, var_ref_vals, true)) 5363 hist_trigger_actions(hist_data, elt, rec, rbe, key, var_ref_vals); 5364 } 5365 5366 static void hist_trigger_stacktrace_print(struct seq_file *m, 5367 unsigned long *stacktrace_entries, 5368 unsigned int max_entries) 5369 { 5370 char str[KSYM_SYMBOL_LEN]; 5371 unsigned int spaces = 8; 5372 unsigned int i; 5373 5374 for (i = 0; i < max_entries; i++) { 5375 if (!stacktrace_entries[i]) 5376 return; 5377 5378 seq_printf(m, "%*c", 1 + spaces, ' '); 5379 sprint_symbol(str, stacktrace_entries[i]); 5380 seq_printf(m, "%s\n", str); 5381 } 5382 } 5383 5384 static void hist_trigger_print_key(struct seq_file *m, 5385 struct hist_trigger_data *hist_data, 5386 void *key, 5387 struct tracing_map_elt *elt) 5388 { 5389 struct hist_field *key_field; 5390 char str[KSYM_SYMBOL_LEN]; 5391 bool multiline = false; 5392 const char *field_name; 5393 unsigned int i; 5394 u64 uval; 5395 5396 seq_puts(m, "{ "); 5397 5398 for_each_hist_key_field(i, hist_data) { 5399 key_field = hist_data->fields[i]; 5400 5401 if (i > hist_data->n_vals) 5402 seq_puts(m, ", "); 5403 5404 field_name = hist_field_name(key_field, 0); 5405 5406 if (key_field->flags & HIST_FIELD_FL_HEX) { 5407 uval = *(u64 *)(key + key_field->offset); 5408 seq_printf(m, "%s: %llx", field_name, uval); 5409 } else if (key_field->flags & HIST_FIELD_FL_SYM) { 5410 uval = *(u64 *)(key + key_field->offset); 5411 sprint_symbol_no_offset(str, uval); 5412 seq_printf(m, "%s: [%llx] %-45s", field_name, 5413 uval, str); 5414 } else if (key_field->flags & HIST_FIELD_FL_SYM_OFFSET) { 5415 uval = *(u64 *)(key + key_field->offset); 5416 sprint_symbol(str, uval); 5417 seq_printf(m, "%s: [%llx] %-55s", field_name, 5418 uval, str); 5419 } else if (key_field->flags & HIST_FIELD_FL_EXECNAME) { 5420 struct hist_elt_data *elt_data = elt->private_data; 5421 char *comm; 5422 5423 if (WARN_ON_ONCE(!elt_data)) 5424 return; 5425 5426 comm = elt_data->comm; 5427 5428 uval = *(u64 *)(key + key_field->offset); 5429 seq_printf(m, "%s: %-16s[%10llu]", field_name, 5430 comm, uval); 5431 } else if (key_field->flags & HIST_FIELD_FL_SYSCALL) { 5432 const char *syscall_name; 5433 5434 uval = *(u64 *)(key + key_field->offset); 5435 syscall_name = get_syscall_name(uval); 5436 if (!syscall_name) 5437 syscall_name = "unknown_syscall"; 5438 5439 seq_printf(m, "%s: %-30s[%3llu]", field_name, 5440 syscall_name, uval); 5441 } else if (key_field->flags & HIST_FIELD_FL_STACKTRACE) { 5442 seq_puts(m, "stacktrace:\n"); 5443 hist_trigger_stacktrace_print(m, 5444 key + key_field->offset, 5445 HIST_STACKTRACE_DEPTH); 5446 multiline = true; 5447 } else if (key_field->flags & HIST_FIELD_FL_LOG2) { 5448 seq_printf(m, "%s: ~ 2^%-2llu", field_name, 5449 *(u64 *)(key + key_field->offset)); 5450 } else if (key_field->flags & HIST_FIELD_FL_STRING) { 5451 seq_printf(m, "%s: %-50s", field_name, 5452 (char *)(key + key_field->offset)); 5453 } else { 5454 uval = *(u64 *)(key + key_field->offset); 5455 seq_printf(m, "%s: %10llu", field_name, uval); 5456 } 5457 } 5458 5459 if (!multiline) 5460 seq_puts(m, " "); 5461 5462 seq_puts(m, "}"); 5463 } 5464 5465 static void hist_trigger_entry_print(struct seq_file *m, 5466 struct hist_trigger_data *hist_data, 5467 void *key, 5468 struct tracing_map_elt *elt) 5469 { 5470 const char *field_name; 5471 unsigned int i; 5472 5473 hist_trigger_print_key(m, hist_data, key, elt); 5474 5475 seq_printf(m, " hitcount: %10llu", 5476 tracing_map_read_sum(elt, HITCOUNT_IDX)); 5477 5478 for (i = 1; i < hist_data->n_vals; i++) { 5479 field_name = hist_field_name(hist_data->fields[i], 0); 5480 5481 if (hist_data->fields[i]->flags & HIST_FIELD_FL_VAR || 5482 hist_data->fields[i]->flags & HIST_FIELD_FL_EXPR) 5483 continue; 5484 5485 if (hist_data->fields[i]->flags & HIST_FIELD_FL_HEX) { 5486 seq_printf(m, " %s: %10llx", field_name, 5487 tracing_map_read_sum(elt, i)); 5488 } else { 5489 seq_printf(m, " %s: %10llu", field_name, 5490 tracing_map_read_sum(elt, i)); 5491 } 5492 } 5493 5494 print_actions(m, hist_data, elt); 5495 5496 seq_puts(m, "\n"); 5497 } 5498 5499 static int print_entries(struct seq_file *m, 5500 struct hist_trigger_data *hist_data) 5501 { 5502 struct tracing_map_sort_entry **sort_entries = NULL; 5503 struct tracing_map *map = hist_data->map; 5504 int i, n_entries; 5505 5506 n_entries = tracing_map_sort_entries(map, hist_data->sort_keys, 5507 hist_data->n_sort_keys, 5508 &sort_entries); 5509 if (n_entries < 0) 5510 return n_entries; 5511 5512 for (i = 0; i < n_entries; i++) 5513 hist_trigger_entry_print(m, hist_data, 5514 sort_entries[i]->key, 5515 sort_entries[i]->elt); 5516 5517 tracing_map_destroy_sort_entries(sort_entries, n_entries); 5518 5519 return n_entries; 5520 } 5521 5522 static void hist_trigger_show(struct seq_file *m, 5523 struct event_trigger_data *data, int n) 5524 { 5525 struct hist_trigger_data *hist_data; 5526 int n_entries; 5527 5528 if (n > 0) 5529 seq_puts(m, "\n\n"); 5530 5531 seq_puts(m, "# event histogram\n#\n# trigger info: "); 5532 data->ops->print(m, data->ops, data); 5533 seq_puts(m, "#\n\n"); 5534 5535 hist_data = data->private_data; 5536 n_entries = print_entries(m, hist_data); 5537 if (n_entries < 0) 5538 n_entries = 0; 5539 5540 track_data_snapshot_print(m, hist_data); 5541 5542 seq_printf(m, "\nTotals:\n Hits: %llu\n Entries: %u\n Dropped: %llu\n", 5543 (u64)atomic64_read(&hist_data->map->hits), 5544 n_entries, (u64)atomic64_read(&hist_data->map->drops)); 5545 } 5546 5547 static int hist_show(struct seq_file *m, void *v) 5548 { 5549 struct event_trigger_data *data; 5550 struct trace_event_file *event_file; 5551 int n = 0, ret = 0; 5552 5553 mutex_lock(&event_mutex); 5554 5555 event_file = event_file_data(m->private); 5556 if (unlikely(!event_file)) { 5557 ret = -ENODEV; 5558 goto out_unlock; 5559 } 5560 5561 list_for_each_entry(data, &event_file->triggers, list) { 5562 if (data->cmd_ops->trigger_type == ETT_EVENT_HIST) 5563 hist_trigger_show(m, data, n++); 5564 } 5565 5566 out_unlock: 5567 mutex_unlock(&event_mutex); 5568 5569 return ret; 5570 } 5571 5572 static int event_hist_open(struct inode *inode, struct file *file) 5573 { 5574 int ret; 5575 5576 ret = security_locked_down(LOCKDOWN_TRACEFS); 5577 if (ret) 5578 return ret; 5579 5580 return single_open(file, hist_show, file); 5581 } 5582 5583 const struct file_operations event_hist_fops = { 5584 .open = event_hist_open, 5585 .read = seq_read, 5586 .llseek = seq_lseek, 5587 .release = single_release, 5588 }; 5589 5590 static void hist_field_print(struct seq_file *m, struct hist_field *hist_field) 5591 { 5592 const char *field_name = hist_field_name(hist_field, 0); 5593 5594 if (hist_field->var.name) 5595 seq_printf(m, "%s=", hist_field->var.name); 5596 5597 if (hist_field->flags & HIST_FIELD_FL_CPU) 5598 seq_puts(m, "cpu"); 5599 else if (field_name) { 5600 if (hist_field->flags & HIST_FIELD_FL_VAR_REF || 5601 hist_field->flags & HIST_FIELD_FL_ALIAS) 5602 seq_putc(m, '$'); 5603 seq_printf(m, "%s", field_name); 5604 } else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP) 5605 seq_puts(m, "common_timestamp"); 5606 5607 if (hist_field->flags) { 5608 if (!(hist_field->flags & HIST_FIELD_FL_VAR_REF) && 5609 !(hist_field->flags & HIST_FIELD_FL_EXPR)) { 5610 const char *flags = get_hist_field_flags(hist_field); 5611 5612 if (flags) 5613 seq_printf(m, ".%s", flags); 5614 } 5615 } 5616 } 5617 5618 static int event_hist_trigger_print(struct seq_file *m, 5619 struct event_trigger_ops *ops, 5620 struct event_trigger_data *data) 5621 { 5622 struct hist_trigger_data *hist_data = data->private_data; 5623 struct hist_field *field; 5624 bool have_var = false; 5625 unsigned int i; 5626 5627 seq_puts(m, "hist:"); 5628 5629 if (data->name) 5630 seq_printf(m, "%s:", data->name); 5631 5632 seq_puts(m, "keys="); 5633 5634 for_each_hist_key_field(i, hist_data) { 5635 field = hist_data->fields[i]; 5636 5637 if (i > hist_data->n_vals) 5638 seq_puts(m, ","); 5639 5640 if (field->flags & HIST_FIELD_FL_STACKTRACE) 5641 seq_puts(m, "stacktrace"); 5642 else 5643 hist_field_print(m, field); 5644 } 5645 5646 seq_puts(m, ":vals="); 5647 5648 for_each_hist_val_field(i, hist_data) { 5649 field = hist_data->fields[i]; 5650 if (field->flags & HIST_FIELD_FL_VAR) { 5651 have_var = true; 5652 continue; 5653 } 5654 5655 if (i == HITCOUNT_IDX) 5656 seq_puts(m, "hitcount"); 5657 else { 5658 seq_puts(m, ","); 5659 hist_field_print(m, field); 5660 } 5661 } 5662 5663 if (have_var) { 5664 unsigned int n = 0; 5665 5666 seq_puts(m, ":"); 5667 5668 for_each_hist_val_field(i, hist_data) { 5669 field = hist_data->fields[i]; 5670 5671 if (field->flags & HIST_FIELD_FL_VAR) { 5672 if (n++) 5673 seq_puts(m, ","); 5674 hist_field_print(m, field); 5675 } 5676 } 5677 } 5678 5679 seq_puts(m, ":sort="); 5680 5681 for (i = 0; i < hist_data->n_sort_keys; i++) { 5682 struct tracing_map_sort_key *sort_key; 5683 unsigned int idx, first_key_idx; 5684 5685 /* skip VAR vals */ 5686 first_key_idx = hist_data->n_vals - hist_data->n_vars; 5687 5688 sort_key = &hist_data->sort_keys[i]; 5689 idx = sort_key->field_idx; 5690 5691 if (WARN_ON(idx >= HIST_FIELDS_MAX)) 5692 return -EINVAL; 5693 5694 if (i > 0) 5695 seq_puts(m, ","); 5696 5697 if (idx == HITCOUNT_IDX) 5698 seq_puts(m, "hitcount"); 5699 else { 5700 if (idx >= first_key_idx) 5701 idx += hist_data->n_vars; 5702 hist_field_print(m, hist_data->fields[idx]); 5703 } 5704 5705 if (sort_key->descending) 5706 seq_puts(m, ".descending"); 5707 } 5708 seq_printf(m, ":size=%u", (1 << hist_data->map->map_bits)); 5709 if (hist_data->enable_timestamps) 5710 seq_printf(m, ":clock=%s", hist_data->attrs->clock); 5711 5712 print_actions_spec(m, hist_data); 5713 5714 if (data->filter_str) 5715 seq_printf(m, " if %s", data->filter_str); 5716 5717 if (data->paused) 5718 seq_puts(m, " [paused]"); 5719 else 5720 seq_puts(m, " [active]"); 5721 5722 seq_putc(m, '\n'); 5723 5724 return 0; 5725 } 5726 5727 static int event_hist_trigger_init(struct event_trigger_ops *ops, 5728 struct event_trigger_data *data) 5729 { 5730 struct hist_trigger_data *hist_data = data->private_data; 5731 5732 if (!data->ref && hist_data->attrs->name) 5733 save_named_trigger(hist_data->attrs->name, data); 5734 5735 data->ref++; 5736 5737 return 0; 5738 } 5739 5740 static void unregister_field_var_hists(struct hist_trigger_data *hist_data) 5741 { 5742 struct trace_event_file *file; 5743 unsigned int i; 5744 char *cmd; 5745 int ret; 5746 5747 for (i = 0; i < hist_data->n_field_var_hists; i++) { 5748 file = hist_data->field_var_hists[i]->hist_data->event_file; 5749 cmd = hist_data->field_var_hists[i]->cmd; 5750 ret = event_hist_trigger_func(&trigger_hist_cmd, file, 5751 "!hist", "hist", cmd); 5752 } 5753 } 5754 5755 static void event_hist_trigger_free(struct event_trigger_ops *ops, 5756 struct event_trigger_data *data) 5757 { 5758 struct hist_trigger_data *hist_data = data->private_data; 5759 5760 if (WARN_ON_ONCE(data->ref <= 0)) 5761 return; 5762 5763 data->ref--; 5764 if (!data->ref) { 5765 if (data->name) 5766 del_named_trigger(data); 5767 5768 trigger_data_free(data); 5769 5770 remove_hist_vars(hist_data); 5771 5772 unregister_field_var_hists(hist_data); 5773 5774 destroy_hist_data(hist_data); 5775 } 5776 } 5777 5778 static struct event_trigger_ops event_hist_trigger_ops = { 5779 .func = event_hist_trigger, 5780 .print = event_hist_trigger_print, 5781 .init = event_hist_trigger_init, 5782 .free = event_hist_trigger_free, 5783 }; 5784 5785 static int event_hist_trigger_named_init(struct event_trigger_ops *ops, 5786 struct event_trigger_data *data) 5787 { 5788 data->ref++; 5789 5790 save_named_trigger(data->named_data->name, data); 5791 5792 event_hist_trigger_init(ops, data->named_data); 5793 5794 return 0; 5795 } 5796 5797 static void event_hist_trigger_named_free(struct event_trigger_ops *ops, 5798 struct event_trigger_data *data) 5799 { 5800 if (WARN_ON_ONCE(data->ref <= 0)) 5801 return; 5802 5803 event_hist_trigger_free(ops, data->named_data); 5804 5805 data->ref--; 5806 if (!data->ref) { 5807 del_named_trigger(data); 5808 trigger_data_free(data); 5809 } 5810 } 5811 5812 static struct event_trigger_ops event_hist_trigger_named_ops = { 5813 .func = event_hist_trigger, 5814 .print = event_hist_trigger_print, 5815 .init = event_hist_trigger_named_init, 5816 .free = event_hist_trigger_named_free, 5817 }; 5818 5819 static struct event_trigger_ops *event_hist_get_trigger_ops(char *cmd, 5820 char *param) 5821 { 5822 return &event_hist_trigger_ops; 5823 } 5824 5825 static void hist_clear(struct event_trigger_data *data) 5826 { 5827 struct hist_trigger_data *hist_data = data->private_data; 5828 5829 if (data->name) 5830 pause_named_trigger(data); 5831 5832 tracepoint_synchronize_unregister(); 5833 5834 tracing_map_clear(hist_data->map); 5835 5836 if (data->name) 5837 unpause_named_trigger(data); 5838 } 5839 5840 static bool compatible_field(struct ftrace_event_field *field, 5841 struct ftrace_event_field *test_field) 5842 { 5843 if (field == test_field) 5844 return true; 5845 if (field == NULL || test_field == NULL) 5846 return false; 5847 if (strcmp(field->name, test_field->name) != 0) 5848 return false; 5849 if (strcmp(field->type, test_field->type) != 0) 5850 return false; 5851 if (field->size != test_field->size) 5852 return false; 5853 if (field->is_signed != test_field->is_signed) 5854 return false; 5855 5856 return true; 5857 } 5858 5859 static bool hist_trigger_match(struct event_trigger_data *data, 5860 struct event_trigger_data *data_test, 5861 struct event_trigger_data *named_data, 5862 bool ignore_filter) 5863 { 5864 struct tracing_map_sort_key *sort_key, *sort_key_test; 5865 struct hist_trigger_data *hist_data, *hist_data_test; 5866 struct hist_field *key_field, *key_field_test; 5867 unsigned int i; 5868 5869 if (named_data && (named_data != data_test) && 5870 (named_data != data_test->named_data)) 5871 return false; 5872 5873 if (!named_data && is_named_trigger(data_test)) 5874 return false; 5875 5876 hist_data = data->private_data; 5877 hist_data_test = data_test->private_data; 5878 5879 if (hist_data->n_vals != hist_data_test->n_vals || 5880 hist_data->n_fields != hist_data_test->n_fields || 5881 hist_data->n_sort_keys != hist_data_test->n_sort_keys) 5882 return false; 5883 5884 if (!ignore_filter) { 5885 if ((data->filter_str && !data_test->filter_str) || 5886 (!data->filter_str && data_test->filter_str)) 5887 return false; 5888 } 5889 5890 for_each_hist_field(i, hist_data) { 5891 key_field = hist_data->fields[i]; 5892 key_field_test = hist_data_test->fields[i]; 5893 5894 if (key_field->flags != key_field_test->flags) 5895 return false; 5896 if (!compatible_field(key_field->field, key_field_test->field)) 5897 return false; 5898 if (key_field->offset != key_field_test->offset) 5899 return false; 5900 if (key_field->size != key_field_test->size) 5901 return false; 5902 if (key_field->is_signed != key_field_test->is_signed) 5903 return false; 5904 if (!!key_field->var.name != !!key_field_test->var.name) 5905 return false; 5906 if (key_field->var.name && 5907 strcmp(key_field->var.name, key_field_test->var.name) != 0) 5908 return false; 5909 } 5910 5911 for (i = 0; i < hist_data->n_sort_keys; i++) { 5912 sort_key = &hist_data->sort_keys[i]; 5913 sort_key_test = &hist_data_test->sort_keys[i]; 5914 5915 if (sort_key->field_idx != sort_key_test->field_idx || 5916 sort_key->descending != sort_key_test->descending) 5917 return false; 5918 } 5919 5920 if (!ignore_filter && data->filter_str && 5921 (strcmp(data->filter_str, data_test->filter_str) != 0)) 5922 return false; 5923 5924 if (!actions_match(hist_data, hist_data_test)) 5925 return false; 5926 5927 return true; 5928 } 5929 5930 static int hist_register_trigger(char *glob, struct event_trigger_ops *ops, 5931 struct event_trigger_data *data, 5932 struct trace_event_file *file) 5933 { 5934 struct hist_trigger_data *hist_data = data->private_data; 5935 struct event_trigger_data *test, *named_data = NULL; 5936 struct trace_array *tr = file->tr; 5937 int ret = 0; 5938 5939 if (hist_data->attrs->name) { 5940 named_data = find_named_trigger(hist_data->attrs->name); 5941 if (named_data) { 5942 if (!hist_trigger_match(data, named_data, named_data, 5943 true)) { 5944 hist_err(tr, HIST_ERR_NAMED_MISMATCH, errpos(hist_data->attrs->name)); 5945 ret = -EINVAL; 5946 goto out; 5947 } 5948 } 5949 } 5950 5951 if (hist_data->attrs->name && !named_data) 5952 goto new; 5953 5954 lockdep_assert_held(&event_mutex); 5955 5956 list_for_each_entry(test, &file->triggers, list) { 5957 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 5958 if (!hist_trigger_match(data, test, named_data, false)) 5959 continue; 5960 if (hist_data->attrs->pause) 5961 test->paused = true; 5962 else if (hist_data->attrs->cont) 5963 test->paused = false; 5964 else if (hist_data->attrs->clear) 5965 hist_clear(test); 5966 else { 5967 hist_err(tr, HIST_ERR_TRIGGER_EEXIST, 0); 5968 ret = -EEXIST; 5969 } 5970 goto out; 5971 } 5972 } 5973 new: 5974 if (hist_data->attrs->cont || hist_data->attrs->clear) { 5975 hist_err(tr, HIST_ERR_TRIGGER_ENOENT_CLEAR, 0); 5976 ret = -ENOENT; 5977 goto out; 5978 } 5979 5980 if (hist_data->attrs->pause) 5981 data->paused = true; 5982 5983 if (named_data) { 5984 data->private_data = named_data->private_data; 5985 set_named_trigger_data(data, named_data); 5986 data->ops = &event_hist_trigger_named_ops; 5987 } 5988 5989 if (data->ops->init) { 5990 ret = data->ops->init(data->ops, data); 5991 if (ret < 0) 5992 goto out; 5993 } 5994 5995 if (hist_data->enable_timestamps) { 5996 char *clock = hist_data->attrs->clock; 5997 5998 ret = tracing_set_clock(file->tr, hist_data->attrs->clock); 5999 if (ret) { 6000 hist_err(tr, HIST_ERR_SET_CLOCK_FAIL, errpos(clock)); 6001 goto out; 6002 } 6003 6004 tracing_set_time_stamp_abs(file->tr, true); 6005 } 6006 6007 if (named_data) 6008 destroy_hist_data(hist_data); 6009 6010 ret++; 6011 out: 6012 return ret; 6013 } 6014 6015 static int hist_trigger_enable(struct event_trigger_data *data, 6016 struct trace_event_file *file) 6017 { 6018 int ret = 0; 6019 6020 list_add_tail_rcu(&data->list, &file->triggers); 6021 6022 update_cond_flag(file); 6023 6024 if (trace_event_trigger_enable_disable(file, 1) < 0) { 6025 list_del_rcu(&data->list); 6026 update_cond_flag(file); 6027 ret--; 6028 } 6029 6030 return ret; 6031 } 6032 6033 static bool have_hist_trigger_match(struct event_trigger_data *data, 6034 struct trace_event_file *file) 6035 { 6036 struct hist_trigger_data *hist_data = data->private_data; 6037 struct event_trigger_data *test, *named_data = NULL; 6038 bool match = false; 6039 6040 lockdep_assert_held(&event_mutex); 6041 6042 if (hist_data->attrs->name) 6043 named_data = find_named_trigger(hist_data->attrs->name); 6044 6045 list_for_each_entry(test, &file->triggers, list) { 6046 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6047 if (hist_trigger_match(data, test, named_data, false)) { 6048 match = true; 6049 break; 6050 } 6051 } 6052 } 6053 6054 return match; 6055 } 6056 6057 static bool hist_trigger_check_refs(struct event_trigger_data *data, 6058 struct trace_event_file *file) 6059 { 6060 struct hist_trigger_data *hist_data = data->private_data; 6061 struct event_trigger_data *test, *named_data = NULL; 6062 6063 lockdep_assert_held(&event_mutex); 6064 6065 if (hist_data->attrs->name) 6066 named_data = find_named_trigger(hist_data->attrs->name); 6067 6068 list_for_each_entry(test, &file->triggers, list) { 6069 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6070 if (!hist_trigger_match(data, test, named_data, false)) 6071 continue; 6072 hist_data = test->private_data; 6073 if (check_var_refs(hist_data)) 6074 return true; 6075 break; 6076 } 6077 } 6078 6079 return false; 6080 } 6081 6082 static void hist_unregister_trigger(char *glob, struct event_trigger_ops *ops, 6083 struct event_trigger_data *data, 6084 struct trace_event_file *file) 6085 { 6086 struct hist_trigger_data *hist_data = data->private_data; 6087 struct event_trigger_data *test, *named_data = NULL; 6088 bool unregistered = false; 6089 6090 lockdep_assert_held(&event_mutex); 6091 6092 if (hist_data->attrs->name) 6093 named_data = find_named_trigger(hist_data->attrs->name); 6094 6095 list_for_each_entry(test, &file->triggers, list) { 6096 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6097 if (!hist_trigger_match(data, test, named_data, false)) 6098 continue; 6099 unregistered = true; 6100 list_del_rcu(&test->list); 6101 trace_event_trigger_enable_disable(file, 0); 6102 update_cond_flag(file); 6103 break; 6104 } 6105 } 6106 6107 if (unregistered && test->ops->free) 6108 test->ops->free(test->ops, test); 6109 6110 if (hist_data->enable_timestamps) { 6111 if (!hist_data->remove || unregistered) 6112 tracing_set_time_stamp_abs(file->tr, false); 6113 } 6114 } 6115 6116 static bool hist_file_check_refs(struct trace_event_file *file) 6117 { 6118 struct hist_trigger_data *hist_data; 6119 struct event_trigger_data *test; 6120 6121 lockdep_assert_held(&event_mutex); 6122 6123 list_for_each_entry(test, &file->triggers, list) { 6124 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6125 hist_data = test->private_data; 6126 if (check_var_refs(hist_data)) 6127 return true; 6128 } 6129 } 6130 6131 return false; 6132 } 6133 6134 static void hist_unreg_all(struct trace_event_file *file) 6135 { 6136 struct event_trigger_data *test, *n; 6137 struct hist_trigger_data *hist_data; 6138 struct synth_event *se; 6139 const char *se_name; 6140 6141 lockdep_assert_held(&event_mutex); 6142 6143 if (hist_file_check_refs(file)) 6144 return; 6145 6146 list_for_each_entry_safe(test, n, &file->triggers, list) { 6147 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6148 hist_data = test->private_data; 6149 list_del_rcu(&test->list); 6150 trace_event_trigger_enable_disable(file, 0); 6151 6152 se_name = trace_event_name(file->event_call); 6153 se = find_synth_event(se_name); 6154 if (se) 6155 se->ref--; 6156 6157 update_cond_flag(file); 6158 if (hist_data->enable_timestamps) 6159 tracing_set_time_stamp_abs(file->tr, false); 6160 if (test->ops->free) 6161 test->ops->free(test->ops, test); 6162 } 6163 } 6164 } 6165 6166 static int event_hist_trigger_func(struct event_command *cmd_ops, 6167 struct trace_event_file *file, 6168 char *glob, char *cmd, char *param) 6169 { 6170 unsigned int hist_trigger_bits = TRACING_MAP_BITS_DEFAULT; 6171 struct event_trigger_data *trigger_data; 6172 struct hist_trigger_attrs *attrs; 6173 struct event_trigger_ops *trigger_ops; 6174 struct hist_trigger_data *hist_data; 6175 struct synth_event *se; 6176 const char *se_name; 6177 bool remove = false; 6178 char *trigger, *p; 6179 int ret = 0; 6180 6181 lockdep_assert_held(&event_mutex); 6182 6183 if (glob && strlen(glob)) { 6184 hist_err_clear(); 6185 last_cmd_set(file, param); 6186 } 6187 6188 if (!param) 6189 return -EINVAL; 6190 6191 if (glob[0] == '!') 6192 remove = true; 6193 6194 /* 6195 * separate the trigger from the filter (k:v [if filter]) 6196 * allowing for whitespace in the trigger 6197 */ 6198 p = trigger = param; 6199 do { 6200 p = strstr(p, "if"); 6201 if (!p) 6202 break; 6203 if (p == param) 6204 return -EINVAL; 6205 if (*(p - 1) != ' ' && *(p - 1) != '\t') { 6206 p++; 6207 continue; 6208 } 6209 if (p >= param + strlen(param) - (sizeof("if") - 1) - 1) 6210 return -EINVAL; 6211 if (*(p + sizeof("if") - 1) != ' ' && *(p + sizeof("if") - 1) != '\t') { 6212 p++; 6213 continue; 6214 } 6215 break; 6216 } while (p); 6217 6218 if (!p) 6219 param = NULL; 6220 else { 6221 *(p - 1) = '\0'; 6222 param = strstrip(p); 6223 trigger = strstrip(trigger); 6224 } 6225 6226 attrs = parse_hist_trigger_attrs(file->tr, trigger); 6227 if (IS_ERR(attrs)) 6228 return PTR_ERR(attrs); 6229 6230 if (attrs->map_bits) 6231 hist_trigger_bits = attrs->map_bits; 6232 6233 hist_data = create_hist_data(hist_trigger_bits, attrs, file, remove); 6234 if (IS_ERR(hist_data)) { 6235 destroy_hist_trigger_attrs(attrs); 6236 return PTR_ERR(hist_data); 6237 } 6238 6239 trigger_ops = cmd_ops->get_trigger_ops(cmd, trigger); 6240 6241 trigger_data = kzalloc(sizeof(*trigger_data), GFP_KERNEL); 6242 if (!trigger_data) { 6243 ret = -ENOMEM; 6244 goto out_free; 6245 } 6246 6247 trigger_data->count = -1; 6248 trigger_data->ops = trigger_ops; 6249 trigger_data->cmd_ops = cmd_ops; 6250 6251 INIT_LIST_HEAD(&trigger_data->list); 6252 RCU_INIT_POINTER(trigger_data->filter, NULL); 6253 6254 trigger_data->private_data = hist_data; 6255 6256 /* if param is non-empty, it's supposed to be a filter */ 6257 if (param && cmd_ops->set_filter) { 6258 ret = cmd_ops->set_filter(param, trigger_data, file); 6259 if (ret < 0) 6260 goto out_free; 6261 } 6262 6263 if (remove) { 6264 if (!have_hist_trigger_match(trigger_data, file)) 6265 goto out_free; 6266 6267 if (hist_trigger_check_refs(trigger_data, file)) { 6268 ret = -EBUSY; 6269 goto out_free; 6270 } 6271 6272 cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file); 6273 se_name = trace_event_name(file->event_call); 6274 se = find_synth_event(se_name); 6275 if (se) 6276 se->ref--; 6277 ret = 0; 6278 goto out_free; 6279 } 6280 6281 ret = cmd_ops->reg(glob, trigger_ops, trigger_data, file); 6282 /* 6283 * The above returns on success the # of triggers registered, 6284 * but if it didn't register any it returns zero. Consider no 6285 * triggers registered a failure too. 6286 */ 6287 if (!ret) { 6288 if (!(attrs->pause || attrs->cont || attrs->clear)) 6289 ret = -ENOENT; 6290 goto out_free; 6291 } else if (ret < 0) 6292 goto out_free; 6293 6294 if (get_named_trigger_data(trigger_data)) 6295 goto enable; 6296 6297 if (has_hist_vars(hist_data)) 6298 save_hist_vars(hist_data); 6299 6300 ret = create_actions(hist_data); 6301 if (ret) 6302 goto out_unreg; 6303 6304 ret = tracing_map_init(hist_data->map); 6305 if (ret) 6306 goto out_unreg; 6307 enable: 6308 ret = hist_trigger_enable(trigger_data, file); 6309 if (ret) 6310 goto out_unreg; 6311 6312 se_name = trace_event_name(file->event_call); 6313 se = find_synth_event(se_name); 6314 if (se) 6315 se->ref++; 6316 /* Just return zero, not the number of registered triggers */ 6317 ret = 0; 6318 out: 6319 if (ret == 0) 6320 hist_err_clear(); 6321 6322 return ret; 6323 out_unreg: 6324 cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file); 6325 out_free: 6326 if (cmd_ops->set_filter) 6327 cmd_ops->set_filter(NULL, trigger_data, NULL); 6328 6329 remove_hist_vars(hist_data); 6330 6331 kfree(trigger_data); 6332 6333 destroy_hist_data(hist_data); 6334 goto out; 6335 } 6336 6337 static struct event_command trigger_hist_cmd = { 6338 .name = "hist", 6339 .trigger_type = ETT_EVENT_HIST, 6340 .flags = EVENT_CMD_FL_NEEDS_REC, 6341 .func = event_hist_trigger_func, 6342 .reg = hist_register_trigger, 6343 .unreg = hist_unregister_trigger, 6344 .unreg_all = hist_unreg_all, 6345 .get_trigger_ops = event_hist_get_trigger_ops, 6346 .set_filter = set_trigger_filter, 6347 }; 6348 6349 __init int register_trigger_hist_cmd(void) 6350 { 6351 int ret; 6352 6353 ret = register_event_command(&trigger_hist_cmd); 6354 WARN_ON(ret < 0); 6355 6356 return ret; 6357 } 6358 6359 static void 6360 hist_enable_trigger(struct event_trigger_data *data, void *rec, 6361 struct ring_buffer_event *event) 6362 { 6363 struct enable_trigger_data *enable_data = data->private_data; 6364 struct event_trigger_data *test; 6365 6366 list_for_each_entry_rcu(test, &enable_data->file->triggers, list, 6367 lockdep_is_held(&event_mutex)) { 6368 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6369 if (enable_data->enable) 6370 test->paused = false; 6371 else 6372 test->paused = true; 6373 } 6374 } 6375 } 6376 6377 static void 6378 hist_enable_count_trigger(struct event_trigger_data *data, void *rec, 6379 struct ring_buffer_event *event) 6380 { 6381 if (!data->count) 6382 return; 6383 6384 if (data->count != -1) 6385 (data->count)--; 6386 6387 hist_enable_trigger(data, rec, event); 6388 } 6389 6390 static struct event_trigger_ops hist_enable_trigger_ops = { 6391 .func = hist_enable_trigger, 6392 .print = event_enable_trigger_print, 6393 .init = event_trigger_init, 6394 .free = event_enable_trigger_free, 6395 }; 6396 6397 static struct event_trigger_ops hist_enable_count_trigger_ops = { 6398 .func = hist_enable_count_trigger, 6399 .print = event_enable_trigger_print, 6400 .init = event_trigger_init, 6401 .free = event_enable_trigger_free, 6402 }; 6403 6404 static struct event_trigger_ops hist_disable_trigger_ops = { 6405 .func = hist_enable_trigger, 6406 .print = event_enable_trigger_print, 6407 .init = event_trigger_init, 6408 .free = event_enable_trigger_free, 6409 }; 6410 6411 static struct event_trigger_ops hist_disable_count_trigger_ops = { 6412 .func = hist_enable_count_trigger, 6413 .print = event_enable_trigger_print, 6414 .init = event_trigger_init, 6415 .free = event_enable_trigger_free, 6416 }; 6417 6418 static struct event_trigger_ops * 6419 hist_enable_get_trigger_ops(char *cmd, char *param) 6420 { 6421 struct event_trigger_ops *ops; 6422 bool enable; 6423 6424 enable = (strcmp(cmd, ENABLE_HIST_STR) == 0); 6425 6426 if (enable) 6427 ops = param ? &hist_enable_count_trigger_ops : 6428 &hist_enable_trigger_ops; 6429 else 6430 ops = param ? &hist_disable_count_trigger_ops : 6431 &hist_disable_trigger_ops; 6432 6433 return ops; 6434 } 6435 6436 static void hist_enable_unreg_all(struct trace_event_file *file) 6437 { 6438 struct event_trigger_data *test, *n; 6439 6440 list_for_each_entry_safe(test, n, &file->triggers, list) { 6441 if (test->cmd_ops->trigger_type == ETT_HIST_ENABLE) { 6442 list_del_rcu(&test->list); 6443 update_cond_flag(file); 6444 trace_event_trigger_enable_disable(file, 0); 6445 if (test->ops->free) 6446 test->ops->free(test->ops, test); 6447 } 6448 } 6449 } 6450 6451 static struct event_command trigger_hist_enable_cmd = { 6452 .name = ENABLE_HIST_STR, 6453 .trigger_type = ETT_HIST_ENABLE, 6454 .func = event_enable_trigger_func, 6455 .reg = event_enable_register_trigger, 6456 .unreg = event_enable_unregister_trigger, 6457 .unreg_all = hist_enable_unreg_all, 6458 .get_trigger_ops = hist_enable_get_trigger_ops, 6459 .set_filter = set_trigger_filter, 6460 }; 6461 6462 static struct event_command trigger_hist_disable_cmd = { 6463 .name = DISABLE_HIST_STR, 6464 .trigger_type = ETT_HIST_ENABLE, 6465 .func = event_enable_trigger_func, 6466 .reg = event_enable_register_trigger, 6467 .unreg = event_enable_unregister_trigger, 6468 .unreg_all = hist_enable_unreg_all, 6469 .get_trigger_ops = hist_enable_get_trigger_ops, 6470 .set_filter = set_trigger_filter, 6471 }; 6472 6473 static __init void unregister_trigger_hist_enable_disable_cmds(void) 6474 { 6475 unregister_event_command(&trigger_hist_enable_cmd); 6476 unregister_event_command(&trigger_hist_disable_cmd); 6477 } 6478 6479 __init int register_trigger_hist_enable_disable_cmds(void) 6480 { 6481 int ret; 6482 6483 ret = register_event_command(&trigger_hist_enable_cmd); 6484 if (WARN_ON(ret < 0)) 6485 return ret; 6486 ret = register_event_command(&trigger_hist_disable_cmd); 6487 if (WARN_ON(ret < 0)) 6488 unregister_trigger_hist_enable_disable_cmds(); 6489 6490 return ret; 6491 } 6492 6493 static __init int trace_events_hist_init(void) 6494 { 6495 struct dentry *entry = NULL; 6496 struct dentry *d_tracer; 6497 int err = 0; 6498 6499 err = dyn_event_register(&synth_event_ops); 6500 if (err) { 6501 pr_warn("Could not register synth_event_ops\n"); 6502 return err; 6503 } 6504 6505 d_tracer = tracing_init_dentry(); 6506 if (IS_ERR(d_tracer)) { 6507 err = PTR_ERR(d_tracer); 6508 goto err; 6509 } 6510 6511 entry = tracefs_create_file("synthetic_events", 0644, d_tracer, 6512 NULL, &synth_events_fops); 6513 if (!entry) { 6514 err = -ENODEV; 6515 goto err; 6516 } 6517 6518 return err; 6519 err: 6520 pr_warn("Could not create tracefs 'synthetic_events' entry\n"); 6521 6522 return err; 6523 } 6524 6525 fs_initcall(trace_events_hist_init); 6526