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