1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * trace_events_hist - trace event hist triggers 4 * 5 * Copyright (C) 2015 Tom Zanussi <tom.zanussi@linux.intel.com> 6 */ 7 8 #include <linux/module.h> 9 #include <linux/kallsyms.h> 10 #include <linux/security.h> 11 #include <linux/mutex.h> 12 #include <linux/slab.h> 13 #include <linux/stacktrace.h> 14 #include <linux/rculist.h> 15 #include <linux/tracefs.h> 16 17 /* for gfp flag names */ 18 #include <linux/trace_events.h> 19 #include <trace/events/mmflags.h> 20 21 #include "tracing_map.h" 22 #include "trace_synth.h" 23 24 #define ERRORS \ 25 C(NONE, "No error"), \ 26 C(DUPLICATE_VAR, "Variable already defined"), \ 27 C(VAR_NOT_UNIQUE, "Variable name not unique, need to use fully qualified name (subsys.event.var) for variable"), \ 28 C(TOO_MANY_VARS, "Too many variables defined"), \ 29 C(MALFORMED_ASSIGNMENT, "Malformed assignment"), \ 30 C(NAMED_MISMATCH, "Named hist trigger doesn't match existing named trigger (includes variables)"), \ 31 C(TRIGGER_EEXIST, "Hist trigger already exists"), \ 32 C(TRIGGER_ENOENT_CLEAR, "Can't clear or continue a nonexistent hist trigger"), \ 33 C(SET_CLOCK_FAIL, "Couldn't set trace_clock"), \ 34 C(BAD_FIELD_MODIFIER, "Invalid field modifier"), \ 35 C(TOO_MANY_SUBEXPR, "Too many subexpressions (3 max)"), \ 36 C(TIMESTAMP_MISMATCH, "Timestamp units in expression don't match"), \ 37 C(TOO_MANY_FIELD_VARS, "Too many field variables defined"), \ 38 C(EVENT_FILE_NOT_FOUND, "Event file not found"), \ 39 C(HIST_NOT_FOUND, "Matching event histogram not found"), \ 40 C(HIST_CREATE_FAIL, "Couldn't create histogram for field"), \ 41 C(SYNTH_VAR_NOT_FOUND, "Couldn't find synthetic variable"), \ 42 C(SYNTH_EVENT_NOT_FOUND,"Couldn't find synthetic event"), \ 43 C(SYNTH_TYPE_MISMATCH, "Param type doesn't match synthetic event field type"), \ 44 C(SYNTH_COUNT_MISMATCH, "Param count doesn't match synthetic event field count"), \ 45 C(FIELD_VAR_PARSE_FAIL, "Couldn't parse field variable"), \ 46 C(VAR_CREATE_FIND_FAIL, "Couldn't create or find variable"), \ 47 C(ONX_NOT_VAR, "For onmax(x) or onchange(x), x must be a variable"), \ 48 C(ONX_VAR_NOT_FOUND, "Couldn't find onmax or onchange variable"), \ 49 C(ONX_VAR_CREATE_FAIL, "Couldn't create onmax or onchange variable"), \ 50 C(FIELD_VAR_CREATE_FAIL,"Couldn't create field variable"), \ 51 C(TOO_MANY_PARAMS, "Too many action params"), \ 52 C(PARAM_NOT_FOUND, "Couldn't find param"), \ 53 C(INVALID_PARAM, "Invalid action param"), \ 54 C(ACTION_NOT_FOUND, "No action found"), \ 55 C(NO_SAVE_PARAMS, "No params found for save()"), \ 56 C(TOO_MANY_SAVE_ACTIONS,"Can't have more than one save() action per hist"), \ 57 C(ACTION_MISMATCH, "Handler doesn't support action"), \ 58 C(NO_CLOSING_PAREN, "No closing paren found"), \ 59 C(SUBSYS_NOT_FOUND, "Missing subsystem"), \ 60 C(INVALID_SUBSYS_EVENT, "Invalid subsystem or event name"), \ 61 C(INVALID_REF_KEY, "Using variable references in keys not supported"), \ 62 C(VAR_NOT_FOUND, "Couldn't find variable"), \ 63 C(FIELD_NOT_FOUND, "Couldn't find field"), \ 64 C(EMPTY_ASSIGNMENT, "Empty assignment"), \ 65 C(INVALID_SORT_MODIFIER,"Invalid sort modifier"), \ 66 C(EMPTY_SORT_FIELD, "Empty sort field"), \ 67 C(TOO_MANY_SORT_FIELDS, "Too many sort fields (Max = 2)"), \ 68 C(INVALID_SORT_FIELD, "Sort field must be a key or a val"), \ 69 C(INVALID_STR_OPERAND, "String type can not be an operand in expression"), \ 70 C(EXPECT_NUMBER, "Expecting numeric literal"), \ 71 C(UNARY_MINUS_SUBEXPR, "Unary minus not supported in sub-expressions"), \ 72 C(DIVISION_BY_ZERO, "Division by zero"), 73 74 #undef C 75 #define C(a, b) HIST_ERR_##a 76 77 enum { ERRORS }; 78 79 #undef C 80 #define C(a, b) b 81 82 static const char *err_text[] = { ERRORS }; 83 84 struct hist_field; 85 86 typedef u64 (*hist_field_fn_t) (struct hist_field *field, 87 struct tracing_map_elt *elt, 88 struct trace_buffer *buffer, 89 struct ring_buffer_event *rbe, 90 void *event); 91 92 #define HIST_FIELD_OPERANDS_MAX 2 93 #define HIST_FIELDS_MAX (TRACING_MAP_FIELDS_MAX + TRACING_MAP_VARS_MAX) 94 #define HIST_ACTIONS_MAX 8 95 #define HIST_CONST_DIGITS_MAX 21 96 #define HIST_DIV_SHIFT 20 /* For optimizing division by constants */ 97 98 enum field_op_id { 99 FIELD_OP_NONE, 100 FIELD_OP_PLUS, 101 FIELD_OP_MINUS, 102 FIELD_OP_UNARY_MINUS, 103 FIELD_OP_DIV, 104 FIELD_OP_MULT, 105 }; 106 107 /* 108 * A hist_var (histogram variable) contains variable information for 109 * hist_fields having the HIST_FIELD_FL_VAR or HIST_FIELD_FL_VAR_REF 110 * flag set. A hist_var has a variable name e.g. ts0, and is 111 * associated with a given histogram trigger, as specified by 112 * hist_data. The hist_var idx is the unique index assigned to the 113 * variable by the hist trigger's tracing_map. The idx is what is 114 * used to set a variable's value and, by a variable reference, to 115 * retrieve it. 116 */ 117 struct hist_var { 118 char *name; 119 struct hist_trigger_data *hist_data; 120 unsigned int idx; 121 }; 122 123 struct hist_field { 124 struct ftrace_event_field *field; 125 unsigned long flags; 126 hist_field_fn_t fn; 127 unsigned int ref; 128 unsigned int size; 129 unsigned int offset; 130 unsigned int is_signed; 131 unsigned long buckets; 132 const char *type; 133 struct hist_field *operands[HIST_FIELD_OPERANDS_MAX]; 134 struct hist_trigger_data *hist_data; 135 136 /* 137 * Variable fields contain variable-specific info in var. 138 */ 139 struct hist_var var; 140 enum field_op_id operator; 141 char *system; 142 char *event_name; 143 144 /* 145 * The name field is used for EXPR and VAR_REF fields. VAR 146 * fields contain the variable name in var.name. 147 */ 148 char *name; 149 150 /* 151 * When a histogram trigger is hit, if it has any references 152 * to variables, the values of those variables are collected 153 * into a var_ref_vals array by resolve_var_refs(). The 154 * current value of each variable is read from the tracing_map 155 * using the hist field's hist_var.idx and entered into the 156 * var_ref_idx entry i.e. var_ref_vals[var_ref_idx]. 157 */ 158 unsigned int var_ref_idx; 159 bool read_once; 160 161 unsigned int var_str_idx; 162 163 /* Numeric literals are represented as u64 */ 164 u64 constant; 165 /* Used to optimize division by constants */ 166 u64 div_multiplier; 167 }; 168 169 static u64 hist_field_none(struct hist_field *field, 170 struct tracing_map_elt *elt, 171 struct trace_buffer *buffer, 172 struct ring_buffer_event *rbe, 173 void *event) 174 { 175 return 0; 176 } 177 178 static u64 hist_field_const(struct hist_field *field, 179 struct tracing_map_elt *elt, 180 struct trace_buffer *buffer, 181 struct ring_buffer_event *rbe, 182 void *event) 183 { 184 return field->constant; 185 } 186 187 static u64 hist_field_counter(struct hist_field *field, 188 struct tracing_map_elt *elt, 189 struct trace_buffer *buffer, 190 struct ring_buffer_event *rbe, 191 void *event) 192 { 193 return 1; 194 } 195 196 static u64 hist_field_string(struct hist_field *hist_field, 197 struct tracing_map_elt *elt, 198 struct trace_buffer *buffer, 199 struct ring_buffer_event *rbe, 200 void *event) 201 { 202 char *addr = (char *)(event + hist_field->field->offset); 203 204 return (u64)(unsigned long)addr; 205 } 206 207 static u64 hist_field_dynstring(struct hist_field *hist_field, 208 struct tracing_map_elt *elt, 209 struct trace_buffer *buffer, 210 struct ring_buffer_event *rbe, 211 void *event) 212 { 213 u32 str_item = *(u32 *)(event + hist_field->field->offset); 214 int str_loc = str_item & 0xffff; 215 char *addr = (char *)(event + str_loc); 216 217 return (u64)(unsigned long)addr; 218 } 219 220 static u64 hist_field_pstring(struct hist_field *hist_field, 221 struct tracing_map_elt *elt, 222 struct trace_buffer *buffer, 223 struct ring_buffer_event *rbe, 224 void *event) 225 { 226 char **addr = (char **)(event + hist_field->field->offset); 227 228 return (u64)(unsigned long)*addr; 229 } 230 231 static u64 hist_field_log2(struct hist_field *hist_field, 232 struct tracing_map_elt *elt, 233 struct trace_buffer *buffer, 234 struct ring_buffer_event *rbe, 235 void *event) 236 { 237 struct hist_field *operand = hist_field->operands[0]; 238 239 u64 val = operand->fn(operand, elt, buffer, rbe, event); 240 241 return (u64) ilog2(roundup_pow_of_two(val)); 242 } 243 244 static u64 hist_field_bucket(struct hist_field *hist_field, 245 struct tracing_map_elt *elt, 246 struct trace_buffer *buffer, 247 struct ring_buffer_event *rbe, 248 void *event) 249 { 250 struct hist_field *operand = hist_field->operands[0]; 251 unsigned long buckets = hist_field->buckets; 252 253 u64 val = operand->fn(operand, elt, buffer, rbe, event); 254 255 if (WARN_ON_ONCE(!buckets)) 256 return val; 257 258 if (val >= LONG_MAX) 259 val = div64_ul(val, buckets); 260 else 261 val = (u64)((unsigned long)val / buckets); 262 return val * buckets; 263 } 264 265 static u64 hist_field_plus(struct hist_field *hist_field, 266 struct tracing_map_elt *elt, 267 struct trace_buffer *buffer, 268 struct ring_buffer_event *rbe, 269 void *event) 270 { 271 struct hist_field *operand1 = hist_field->operands[0]; 272 struct hist_field *operand2 = hist_field->operands[1]; 273 274 u64 val1 = operand1->fn(operand1, elt, buffer, rbe, event); 275 u64 val2 = operand2->fn(operand2, elt, buffer, rbe, event); 276 277 return val1 + val2; 278 } 279 280 static u64 hist_field_minus(struct hist_field *hist_field, 281 struct tracing_map_elt *elt, 282 struct trace_buffer *buffer, 283 struct ring_buffer_event *rbe, 284 void *event) 285 { 286 struct hist_field *operand1 = hist_field->operands[0]; 287 struct hist_field *operand2 = hist_field->operands[1]; 288 289 u64 val1 = operand1->fn(operand1, elt, buffer, rbe, event); 290 u64 val2 = operand2->fn(operand2, elt, buffer, rbe, event); 291 292 return val1 - val2; 293 } 294 295 static u64 hist_field_div(struct hist_field *hist_field, 296 struct tracing_map_elt *elt, 297 struct trace_buffer *buffer, 298 struct ring_buffer_event *rbe, 299 void *event) 300 { 301 struct hist_field *operand1 = hist_field->operands[0]; 302 struct hist_field *operand2 = hist_field->operands[1]; 303 304 u64 val1 = operand1->fn(operand1, elt, buffer, rbe, event); 305 u64 val2 = operand2->fn(operand2, elt, buffer, rbe, event); 306 307 /* Return -1 for the undefined case */ 308 if (!val2) 309 return -1; 310 311 /* Use shift if the divisor is a power of 2 */ 312 if (!(val2 & (val2 - 1))) 313 return val1 >> __ffs64(val2); 314 315 return div64_u64(val1, val2); 316 } 317 318 static u64 div_by_power_of_two(struct hist_field *hist_field, 319 struct tracing_map_elt *elt, 320 struct trace_buffer *buffer, 321 struct ring_buffer_event *rbe, 322 void *event) 323 { 324 struct hist_field *operand1 = hist_field->operands[0]; 325 struct hist_field *operand2 = hist_field->operands[1]; 326 327 u64 val1 = operand1->fn(operand1, elt, buffer, rbe, event); 328 329 return val1 >> __ffs64(operand2->constant); 330 } 331 332 static u64 div_by_not_power_of_two(struct hist_field *hist_field, 333 struct tracing_map_elt *elt, 334 struct trace_buffer *buffer, 335 struct ring_buffer_event *rbe, 336 void *event) 337 { 338 struct hist_field *operand1 = hist_field->operands[0]; 339 struct hist_field *operand2 = hist_field->operands[1]; 340 341 u64 val1 = operand1->fn(operand1, elt, buffer, rbe, event); 342 343 return div64_u64(val1, operand2->constant); 344 } 345 346 static u64 div_by_mult_and_shift(struct hist_field *hist_field, 347 struct tracing_map_elt *elt, 348 struct trace_buffer *buffer, 349 struct ring_buffer_event *rbe, 350 void *event) 351 { 352 struct hist_field *operand1 = hist_field->operands[0]; 353 struct hist_field *operand2 = hist_field->operands[1]; 354 355 u64 val1 = operand1->fn(operand1, elt, buffer, rbe, event); 356 357 /* 358 * If the divisor is a constant, do a multiplication and shift instead. 359 * 360 * Choose Z = some power of 2. If Y <= Z, then: 361 * X / Y = (X * (Z / Y)) / Z 362 * 363 * (Z / Y) is a constant (mult) which is calculated at parse time, so: 364 * X / Y = (X * mult) / Z 365 * 366 * The division by Z can be replaced by a shift since Z is a power of 2: 367 * X / Y = (X * mult) >> HIST_DIV_SHIFT 368 * 369 * As long, as X < Z the results will not be off by more than 1. 370 */ 371 if (val1 < (1 << HIST_DIV_SHIFT)) { 372 u64 mult = operand2->div_multiplier; 373 374 return (val1 * mult + ((1 << HIST_DIV_SHIFT) - 1)) >> HIST_DIV_SHIFT; 375 } 376 377 return div64_u64(val1, operand2->constant); 378 } 379 380 static u64 hist_field_mult(struct hist_field *hist_field, 381 struct tracing_map_elt *elt, 382 struct trace_buffer *buffer, 383 struct ring_buffer_event *rbe, 384 void *event) 385 { 386 struct hist_field *operand1 = hist_field->operands[0]; 387 struct hist_field *operand2 = hist_field->operands[1]; 388 389 u64 val1 = operand1->fn(operand1, elt, buffer, rbe, event); 390 u64 val2 = operand2->fn(operand2, elt, buffer, rbe, event); 391 392 return val1 * val2; 393 } 394 395 static u64 hist_field_unary_minus(struct hist_field *hist_field, 396 struct tracing_map_elt *elt, 397 struct trace_buffer *buffer, 398 struct ring_buffer_event *rbe, 399 void *event) 400 { 401 struct hist_field *operand = hist_field->operands[0]; 402 403 s64 sval = (s64)operand->fn(operand, elt, buffer, rbe, event); 404 u64 val = (u64)-sval; 405 406 return val; 407 } 408 409 #define DEFINE_HIST_FIELD_FN(type) \ 410 static u64 hist_field_##type(struct hist_field *hist_field, \ 411 struct tracing_map_elt *elt, \ 412 struct trace_buffer *buffer, \ 413 struct ring_buffer_event *rbe, \ 414 void *event) \ 415 { \ 416 type *addr = (type *)(event + hist_field->field->offset); \ 417 \ 418 return (u64)(unsigned long)*addr; \ 419 } 420 421 DEFINE_HIST_FIELD_FN(s64); 422 DEFINE_HIST_FIELD_FN(u64); 423 DEFINE_HIST_FIELD_FN(s32); 424 DEFINE_HIST_FIELD_FN(u32); 425 DEFINE_HIST_FIELD_FN(s16); 426 DEFINE_HIST_FIELD_FN(u16); 427 DEFINE_HIST_FIELD_FN(s8); 428 DEFINE_HIST_FIELD_FN(u8); 429 430 #define for_each_hist_field(i, hist_data) \ 431 for ((i) = 0; (i) < (hist_data)->n_fields; (i)++) 432 433 #define for_each_hist_val_field(i, hist_data) \ 434 for ((i) = 0; (i) < (hist_data)->n_vals; (i)++) 435 436 #define for_each_hist_key_field(i, hist_data) \ 437 for ((i) = (hist_data)->n_vals; (i) < (hist_data)->n_fields; (i)++) 438 439 #define HIST_STACKTRACE_DEPTH 16 440 #define HIST_STACKTRACE_SIZE (HIST_STACKTRACE_DEPTH * sizeof(unsigned long)) 441 #define HIST_STACKTRACE_SKIP 5 442 443 #define HITCOUNT_IDX 0 444 #define HIST_KEY_SIZE_MAX (MAX_FILTER_STR_VAL + HIST_STACKTRACE_SIZE) 445 446 enum hist_field_flags { 447 HIST_FIELD_FL_HITCOUNT = 1 << 0, 448 HIST_FIELD_FL_KEY = 1 << 1, 449 HIST_FIELD_FL_STRING = 1 << 2, 450 HIST_FIELD_FL_HEX = 1 << 3, 451 HIST_FIELD_FL_SYM = 1 << 4, 452 HIST_FIELD_FL_SYM_OFFSET = 1 << 5, 453 HIST_FIELD_FL_EXECNAME = 1 << 6, 454 HIST_FIELD_FL_SYSCALL = 1 << 7, 455 HIST_FIELD_FL_STACKTRACE = 1 << 8, 456 HIST_FIELD_FL_LOG2 = 1 << 9, 457 HIST_FIELD_FL_TIMESTAMP = 1 << 10, 458 HIST_FIELD_FL_TIMESTAMP_USECS = 1 << 11, 459 HIST_FIELD_FL_VAR = 1 << 12, 460 HIST_FIELD_FL_EXPR = 1 << 13, 461 HIST_FIELD_FL_VAR_REF = 1 << 14, 462 HIST_FIELD_FL_CPU = 1 << 15, 463 HIST_FIELD_FL_ALIAS = 1 << 16, 464 HIST_FIELD_FL_BUCKET = 1 << 17, 465 HIST_FIELD_FL_CONST = 1 << 18, 466 }; 467 468 struct var_defs { 469 unsigned int n_vars; 470 char *name[TRACING_MAP_VARS_MAX]; 471 char *expr[TRACING_MAP_VARS_MAX]; 472 }; 473 474 struct hist_trigger_attrs { 475 char *keys_str; 476 char *vals_str; 477 char *sort_key_str; 478 char *name; 479 char *clock; 480 bool pause; 481 bool cont; 482 bool clear; 483 bool ts_in_usecs; 484 unsigned int map_bits; 485 486 char *assignment_str[TRACING_MAP_VARS_MAX]; 487 unsigned int n_assignments; 488 489 char *action_str[HIST_ACTIONS_MAX]; 490 unsigned int n_actions; 491 492 struct var_defs var_defs; 493 }; 494 495 struct field_var { 496 struct hist_field *var; 497 struct hist_field *val; 498 }; 499 500 struct field_var_hist { 501 struct hist_trigger_data *hist_data; 502 char *cmd; 503 }; 504 505 struct hist_trigger_data { 506 struct hist_field *fields[HIST_FIELDS_MAX]; 507 unsigned int n_vals; 508 unsigned int n_keys; 509 unsigned int n_fields; 510 unsigned int n_vars; 511 unsigned int n_var_str; 512 unsigned int key_size; 513 struct tracing_map_sort_key sort_keys[TRACING_MAP_SORT_KEYS_MAX]; 514 unsigned int n_sort_keys; 515 struct trace_event_file *event_file; 516 struct hist_trigger_attrs *attrs; 517 struct tracing_map *map; 518 bool enable_timestamps; 519 bool remove; 520 struct hist_field *var_refs[TRACING_MAP_VARS_MAX]; 521 unsigned int n_var_refs; 522 523 struct action_data *actions[HIST_ACTIONS_MAX]; 524 unsigned int n_actions; 525 526 struct field_var *field_vars[SYNTH_FIELDS_MAX]; 527 unsigned int n_field_vars; 528 unsigned int n_field_var_str; 529 struct field_var_hist *field_var_hists[SYNTH_FIELDS_MAX]; 530 unsigned int n_field_var_hists; 531 532 struct field_var *save_vars[SYNTH_FIELDS_MAX]; 533 unsigned int n_save_vars; 534 unsigned int n_save_var_str; 535 }; 536 537 struct action_data; 538 539 typedef void (*action_fn_t) (struct hist_trigger_data *hist_data, 540 struct tracing_map_elt *elt, 541 struct trace_buffer *buffer, void *rec, 542 struct ring_buffer_event *rbe, void *key, 543 struct action_data *data, u64 *var_ref_vals); 544 545 typedef bool (*check_track_val_fn_t) (u64 track_val, u64 var_val); 546 547 enum handler_id { 548 HANDLER_ONMATCH = 1, 549 HANDLER_ONMAX, 550 HANDLER_ONCHANGE, 551 }; 552 553 enum action_id { 554 ACTION_SAVE = 1, 555 ACTION_TRACE, 556 ACTION_SNAPSHOT, 557 }; 558 559 struct action_data { 560 enum handler_id handler; 561 enum action_id action; 562 char *action_name; 563 action_fn_t fn; 564 565 unsigned int n_params; 566 char *params[SYNTH_FIELDS_MAX]; 567 568 /* 569 * When a histogram trigger is hit, the values of any 570 * references to variables, including variables being passed 571 * as parameters to synthetic events, are collected into a 572 * var_ref_vals array. This var_ref_idx array is an array of 573 * indices into the var_ref_vals array, one for each synthetic 574 * event param, and is passed to the synthetic event 575 * invocation. 576 */ 577 unsigned int var_ref_idx[TRACING_MAP_VARS_MAX]; 578 struct synth_event *synth_event; 579 bool use_trace_keyword; 580 char *synth_event_name; 581 582 union { 583 struct { 584 char *event; 585 char *event_system; 586 } match_data; 587 588 struct { 589 /* 590 * var_str contains the $-unstripped variable 591 * name referenced by var_ref, and used when 592 * printing the action. Because var_ref 593 * creation is deferred to create_actions(), 594 * we need a per-action way to save it until 595 * then, thus var_str. 596 */ 597 char *var_str; 598 599 /* 600 * var_ref refers to the variable being 601 * tracked e.g onmax($var). 602 */ 603 struct hist_field *var_ref; 604 605 /* 606 * track_var contains the 'invisible' tracking 607 * variable created to keep the current 608 * e.g. max value. 609 */ 610 struct hist_field *track_var; 611 612 check_track_val_fn_t check_val; 613 action_fn_t save_data; 614 } track_data; 615 }; 616 }; 617 618 struct track_data { 619 u64 track_val; 620 bool updated; 621 622 unsigned int key_len; 623 void *key; 624 struct tracing_map_elt elt; 625 626 struct action_data *action_data; 627 struct hist_trigger_data *hist_data; 628 }; 629 630 struct hist_elt_data { 631 char *comm; 632 u64 *var_ref_vals; 633 char **field_var_str; 634 int n_field_var_str; 635 }; 636 637 struct snapshot_context { 638 struct tracing_map_elt *elt; 639 void *key; 640 }; 641 642 /* 643 * Returns the specific division function to use if the divisor 644 * is constant. This avoids extra branches when the trigger is hit. 645 */ 646 static hist_field_fn_t hist_field_get_div_fn(struct hist_field *divisor) 647 { 648 u64 div = divisor->constant; 649 650 if (!(div & (div - 1))) 651 return div_by_power_of_two; 652 653 /* If the divisor is too large, do a regular division */ 654 if (div > (1 << HIST_DIV_SHIFT)) 655 return div_by_not_power_of_two; 656 657 divisor->div_multiplier = div64_u64((u64)(1 << HIST_DIV_SHIFT), div); 658 return div_by_mult_and_shift; 659 } 660 661 static void track_data_free(struct track_data *track_data) 662 { 663 struct hist_elt_data *elt_data; 664 665 if (!track_data) 666 return; 667 668 kfree(track_data->key); 669 670 elt_data = track_data->elt.private_data; 671 if (elt_data) { 672 kfree(elt_data->comm); 673 kfree(elt_data); 674 } 675 676 kfree(track_data); 677 } 678 679 static struct track_data *track_data_alloc(unsigned int key_len, 680 struct action_data *action_data, 681 struct hist_trigger_data *hist_data) 682 { 683 struct track_data *data = kzalloc(sizeof(*data), GFP_KERNEL); 684 struct hist_elt_data *elt_data; 685 686 if (!data) 687 return ERR_PTR(-ENOMEM); 688 689 data->key = kzalloc(key_len, GFP_KERNEL); 690 if (!data->key) { 691 track_data_free(data); 692 return ERR_PTR(-ENOMEM); 693 } 694 695 data->key_len = key_len; 696 data->action_data = action_data; 697 data->hist_data = hist_data; 698 699 elt_data = kzalloc(sizeof(*elt_data), GFP_KERNEL); 700 if (!elt_data) { 701 track_data_free(data); 702 return ERR_PTR(-ENOMEM); 703 } 704 705 data->elt.private_data = elt_data; 706 707 elt_data->comm = kzalloc(TASK_COMM_LEN, GFP_KERNEL); 708 if (!elt_data->comm) { 709 track_data_free(data); 710 return ERR_PTR(-ENOMEM); 711 } 712 713 return data; 714 } 715 716 static char last_cmd[MAX_FILTER_STR_VAL]; 717 static char last_cmd_loc[MAX_FILTER_STR_VAL]; 718 719 static int errpos(char *str) 720 { 721 return err_pos(last_cmd, str); 722 } 723 724 static void last_cmd_set(struct trace_event_file *file, char *str) 725 { 726 const char *system = NULL, *name = NULL; 727 struct trace_event_call *call; 728 729 if (!str) 730 return; 731 732 strcpy(last_cmd, "hist:"); 733 strncat(last_cmd, str, MAX_FILTER_STR_VAL - 1 - sizeof("hist:")); 734 735 if (file) { 736 call = file->event_call; 737 system = call->class->system; 738 if (system) { 739 name = trace_event_name(call); 740 if (!name) 741 system = NULL; 742 } 743 } 744 745 if (system) 746 snprintf(last_cmd_loc, MAX_FILTER_STR_VAL, "hist:%s:%s", system, name); 747 } 748 749 static void hist_err(struct trace_array *tr, u8 err_type, u8 err_pos) 750 { 751 tracing_log_err(tr, last_cmd_loc, last_cmd, err_text, 752 err_type, err_pos); 753 } 754 755 static void hist_err_clear(void) 756 { 757 last_cmd[0] = '\0'; 758 last_cmd_loc[0] = '\0'; 759 } 760 761 typedef void (*synth_probe_func_t) (void *__data, u64 *var_ref_vals, 762 unsigned int *var_ref_idx); 763 764 static inline void trace_synth(struct synth_event *event, u64 *var_ref_vals, 765 unsigned int *var_ref_idx) 766 { 767 struct tracepoint *tp = event->tp; 768 769 if (unlikely(atomic_read(&tp->key.enabled) > 0)) { 770 struct tracepoint_func *probe_func_ptr; 771 synth_probe_func_t probe_func; 772 void *__data; 773 774 if (!(cpu_online(raw_smp_processor_id()))) 775 return; 776 777 probe_func_ptr = rcu_dereference_sched((tp)->funcs); 778 if (probe_func_ptr) { 779 do { 780 probe_func = probe_func_ptr->func; 781 __data = probe_func_ptr->data; 782 probe_func(__data, var_ref_vals, var_ref_idx); 783 } while ((++probe_func_ptr)->func); 784 } 785 } 786 } 787 788 static void action_trace(struct hist_trigger_data *hist_data, 789 struct tracing_map_elt *elt, 790 struct trace_buffer *buffer, void *rec, 791 struct ring_buffer_event *rbe, void *key, 792 struct action_data *data, u64 *var_ref_vals) 793 { 794 struct synth_event *event = data->synth_event; 795 796 trace_synth(event, var_ref_vals, data->var_ref_idx); 797 } 798 799 struct hist_var_data { 800 struct list_head list; 801 struct hist_trigger_data *hist_data; 802 }; 803 804 static u64 hist_field_timestamp(struct hist_field *hist_field, 805 struct tracing_map_elt *elt, 806 struct trace_buffer *buffer, 807 struct ring_buffer_event *rbe, 808 void *event) 809 { 810 struct hist_trigger_data *hist_data = hist_field->hist_data; 811 struct trace_array *tr = hist_data->event_file->tr; 812 813 u64 ts = ring_buffer_event_time_stamp(buffer, rbe); 814 815 if (hist_data->attrs->ts_in_usecs && trace_clock_in_ns(tr)) 816 ts = ns2usecs(ts); 817 818 return ts; 819 } 820 821 static u64 hist_field_cpu(struct hist_field *hist_field, 822 struct tracing_map_elt *elt, 823 struct trace_buffer *buffer, 824 struct ring_buffer_event *rbe, 825 void *event) 826 { 827 int cpu = smp_processor_id(); 828 829 return cpu; 830 } 831 832 /** 833 * check_field_for_var_ref - Check if a VAR_REF field references a variable 834 * @hist_field: The VAR_REF field to check 835 * @var_data: The hist trigger that owns the variable 836 * @var_idx: The trigger variable identifier 837 * 838 * Check the given VAR_REF field to see whether or not it references 839 * the given variable associated with the given trigger. 840 * 841 * Return: The VAR_REF field if it does reference the variable, NULL if not 842 */ 843 static struct hist_field * 844 check_field_for_var_ref(struct hist_field *hist_field, 845 struct hist_trigger_data *var_data, 846 unsigned int var_idx) 847 { 848 WARN_ON(!(hist_field && hist_field->flags & HIST_FIELD_FL_VAR_REF)); 849 850 if (hist_field && hist_field->var.idx == var_idx && 851 hist_field->var.hist_data == var_data) 852 return hist_field; 853 854 return NULL; 855 } 856 857 /** 858 * find_var_ref - Check if a trigger has a reference to a trigger variable 859 * @hist_data: The hist trigger that might have a reference to the variable 860 * @var_data: The hist trigger that owns the variable 861 * @var_idx: The trigger variable identifier 862 * 863 * Check the list of var_refs[] on the first hist trigger to see 864 * whether any of them are references to the variable on the second 865 * trigger. 866 * 867 * Return: The VAR_REF field referencing the variable if so, NULL if not 868 */ 869 static struct hist_field *find_var_ref(struct hist_trigger_data *hist_data, 870 struct hist_trigger_data *var_data, 871 unsigned int var_idx) 872 { 873 struct hist_field *hist_field; 874 unsigned int i; 875 876 for (i = 0; i < hist_data->n_var_refs; i++) { 877 hist_field = hist_data->var_refs[i]; 878 if (check_field_for_var_ref(hist_field, var_data, var_idx)) 879 return hist_field; 880 } 881 882 return NULL; 883 } 884 885 /** 886 * find_any_var_ref - Check if there is a reference to a given trigger variable 887 * @hist_data: The hist trigger 888 * @var_idx: The trigger variable identifier 889 * 890 * Check to see whether the given variable is currently referenced by 891 * any other trigger. 892 * 893 * The trigger the variable is defined on is explicitly excluded - the 894 * assumption being that a self-reference doesn't prevent a trigger 895 * from being removed. 896 * 897 * Return: The VAR_REF field referencing the variable if so, NULL if not 898 */ 899 static struct hist_field *find_any_var_ref(struct hist_trigger_data *hist_data, 900 unsigned int var_idx) 901 { 902 struct trace_array *tr = hist_data->event_file->tr; 903 struct hist_field *found = NULL; 904 struct hist_var_data *var_data; 905 906 list_for_each_entry(var_data, &tr->hist_vars, list) { 907 if (var_data->hist_data == hist_data) 908 continue; 909 found = find_var_ref(var_data->hist_data, hist_data, var_idx); 910 if (found) 911 break; 912 } 913 914 return found; 915 } 916 917 /** 918 * check_var_refs - Check if there is a reference to any of trigger's variables 919 * @hist_data: The hist trigger 920 * 921 * A trigger can define one or more variables. If any one of them is 922 * currently referenced by any other trigger, this function will 923 * determine that. 924 925 * Typically used to determine whether or not a trigger can be removed 926 * - if there are any references to a trigger's variables, it cannot. 927 * 928 * Return: True if there is a reference to any of trigger's variables 929 */ 930 static bool check_var_refs(struct hist_trigger_data *hist_data) 931 { 932 struct hist_field *field; 933 bool found = false; 934 int i; 935 936 for_each_hist_field(i, hist_data) { 937 field = hist_data->fields[i]; 938 if (field && field->flags & HIST_FIELD_FL_VAR) { 939 if (find_any_var_ref(hist_data, field->var.idx)) { 940 found = true; 941 break; 942 } 943 } 944 } 945 946 return found; 947 } 948 949 static struct hist_var_data *find_hist_vars(struct hist_trigger_data *hist_data) 950 { 951 struct trace_array *tr = hist_data->event_file->tr; 952 struct hist_var_data *var_data, *found = NULL; 953 954 list_for_each_entry(var_data, &tr->hist_vars, list) { 955 if (var_data->hist_data == hist_data) { 956 found = var_data; 957 break; 958 } 959 } 960 961 return found; 962 } 963 964 static bool field_has_hist_vars(struct hist_field *hist_field, 965 unsigned int level) 966 { 967 int i; 968 969 if (level > 3) 970 return false; 971 972 if (!hist_field) 973 return false; 974 975 if (hist_field->flags & HIST_FIELD_FL_VAR || 976 hist_field->flags & HIST_FIELD_FL_VAR_REF) 977 return true; 978 979 for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++) { 980 struct hist_field *operand; 981 982 operand = hist_field->operands[i]; 983 if (field_has_hist_vars(operand, level + 1)) 984 return true; 985 } 986 987 return false; 988 } 989 990 static bool has_hist_vars(struct hist_trigger_data *hist_data) 991 { 992 struct hist_field *hist_field; 993 int i; 994 995 for_each_hist_field(i, hist_data) { 996 hist_field = hist_data->fields[i]; 997 if (field_has_hist_vars(hist_field, 0)) 998 return true; 999 } 1000 1001 return false; 1002 } 1003 1004 static int save_hist_vars(struct hist_trigger_data *hist_data) 1005 { 1006 struct trace_array *tr = hist_data->event_file->tr; 1007 struct hist_var_data *var_data; 1008 1009 var_data = find_hist_vars(hist_data); 1010 if (var_data) 1011 return 0; 1012 1013 if (tracing_check_open_get_tr(tr)) 1014 return -ENODEV; 1015 1016 var_data = kzalloc(sizeof(*var_data), GFP_KERNEL); 1017 if (!var_data) { 1018 trace_array_put(tr); 1019 return -ENOMEM; 1020 } 1021 1022 var_data->hist_data = hist_data; 1023 list_add(&var_data->list, &tr->hist_vars); 1024 1025 return 0; 1026 } 1027 1028 static void remove_hist_vars(struct hist_trigger_data *hist_data) 1029 { 1030 struct trace_array *tr = hist_data->event_file->tr; 1031 struct hist_var_data *var_data; 1032 1033 var_data = find_hist_vars(hist_data); 1034 if (!var_data) 1035 return; 1036 1037 if (WARN_ON(check_var_refs(hist_data))) 1038 return; 1039 1040 list_del(&var_data->list); 1041 1042 kfree(var_data); 1043 1044 trace_array_put(tr); 1045 } 1046 1047 static struct hist_field *find_var_field(struct hist_trigger_data *hist_data, 1048 const char *var_name) 1049 { 1050 struct hist_field *hist_field, *found = NULL; 1051 int i; 1052 1053 for_each_hist_field(i, hist_data) { 1054 hist_field = hist_data->fields[i]; 1055 if (hist_field && hist_field->flags & HIST_FIELD_FL_VAR && 1056 strcmp(hist_field->var.name, var_name) == 0) { 1057 found = hist_field; 1058 break; 1059 } 1060 } 1061 1062 return found; 1063 } 1064 1065 static struct hist_field *find_var(struct hist_trigger_data *hist_data, 1066 struct trace_event_file *file, 1067 const char *var_name) 1068 { 1069 struct hist_trigger_data *test_data; 1070 struct event_trigger_data *test; 1071 struct hist_field *hist_field; 1072 1073 lockdep_assert_held(&event_mutex); 1074 1075 hist_field = find_var_field(hist_data, var_name); 1076 if (hist_field) 1077 return hist_field; 1078 1079 list_for_each_entry(test, &file->triggers, list) { 1080 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 1081 test_data = test->private_data; 1082 hist_field = find_var_field(test_data, var_name); 1083 if (hist_field) 1084 return hist_field; 1085 } 1086 } 1087 1088 return NULL; 1089 } 1090 1091 static struct trace_event_file *find_var_file(struct trace_array *tr, 1092 char *system, 1093 char *event_name, 1094 char *var_name) 1095 { 1096 struct hist_trigger_data *var_hist_data; 1097 struct hist_var_data *var_data; 1098 struct trace_event_file *file, *found = NULL; 1099 1100 if (system) 1101 return find_event_file(tr, system, event_name); 1102 1103 list_for_each_entry(var_data, &tr->hist_vars, list) { 1104 var_hist_data = var_data->hist_data; 1105 file = var_hist_data->event_file; 1106 if (file == found) 1107 continue; 1108 1109 if (find_var_field(var_hist_data, var_name)) { 1110 if (found) { 1111 hist_err(tr, HIST_ERR_VAR_NOT_UNIQUE, errpos(var_name)); 1112 return NULL; 1113 } 1114 1115 found = file; 1116 } 1117 } 1118 1119 return found; 1120 } 1121 1122 static struct hist_field *find_file_var(struct trace_event_file *file, 1123 const char *var_name) 1124 { 1125 struct hist_trigger_data *test_data; 1126 struct event_trigger_data *test; 1127 struct hist_field *hist_field; 1128 1129 lockdep_assert_held(&event_mutex); 1130 1131 list_for_each_entry(test, &file->triggers, list) { 1132 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 1133 test_data = test->private_data; 1134 hist_field = find_var_field(test_data, var_name); 1135 if (hist_field) 1136 return hist_field; 1137 } 1138 } 1139 1140 return NULL; 1141 } 1142 1143 static struct hist_field * 1144 find_match_var(struct hist_trigger_data *hist_data, char *var_name) 1145 { 1146 struct trace_array *tr = hist_data->event_file->tr; 1147 struct hist_field *hist_field, *found = NULL; 1148 struct trace_event_file *file; 1149 unsigned int i; 1150 1151 for (i = 0; i < hist_data->n_actions; i++) { 1152 struct action_data *data = hist_data->actions[i]; 1153 1154 if (data->handler == HANDLER_ONMATCH) { 1155 char *system = data->match_data.event_system; 1156 char *event_name = data->match_data.event; 1157 1158 file = find_var_file(tr, system, event_name, var_name); 1159 if (!file) 1160 continue; 1161 hist_field = find_file_var(file, var_name); 1162 if (hist_field) { 1163 if (found) { 1164 hist_err(tr, HIST_ERR_VAR_NOT_UNIQUE, 1165 errpos(var_name)); 1166 return ERR_PTR(-EINVAL); 1167 } 1168 1169 found = hist_field; 1170 } 1171 } 1172 } 1173 return found; 1174 } 1175 1176 static struct hist_field *find_event_var(struct hist_trigger_data *hist_data, 1177 char *system, 1178 char *event_name, 1179 char *var_name) 1180 { 1181 struct trace_array *tr = hist_data->event_file->tr; 1182 struct hist_field *hist_field = NULL; 1183 struct trace_event_file *file; 1184 1185 if (!system || !event_name) { 1186 hist_field = find_match_var(hist_data, var_name); 1187 if (IS_ERR(hist_field)) 1188 return NULL; 1189 if (hist_field) 1190 return hist_field; 1191 } 1192 1193 file = find_var_file(tr, system, event_name, var_name); 1194 if (!file) 1195 return NULL; 1196 1197 hist_field = find_file_var(file, var_name); 1198 1199 return hist_field; 1200 } 1201 1202 static u64 hist_field_var_ref(struct hist_field *hist_field, 1203 struct tracing_map_elt *elt, 1204 struct trace_buffer *buffer, 1205 struct ring_buffer_event *rbe, 1206 void *event) 1207 { 1208 struct hist_elt_data *elt_data; 1209 u64 var_val = 0; 1210 1211 if (WARN_ON_ONCE(!elt)) 1212 return var_val; 1213 1214 elt_data = elt->private_data; 1215 var_val = elt_data->var_ref_vals[hist_field->var_ref_idx]; 1216 1217 return var_val; 1218 } 1219 1220 static bool resolve_var_refs(struct hist_trigger_data *hist_data, void *key, 1221 u64 *var_ref_vals, bool self) 1222 { 1223 struct hist_trigger_data *var_data; 1224 struct tracing_map_elt *var_elt; 1225 struct hist_field *hist_field; 1226 unsigned int i, var_idx; 1227 bool resolved = true; 1228 u64 var_val = 0; 1229 1230 for (i = 0; i < hist_data->n_var_refs; i++) { 1231 hist_field = hist_data->var_refs[i]; 1232 var_idx = hist_field->var.idx; 1233 var_data = hist_field->var.hist_data; 1234 1235 if (var_data == NULL) { 1236 resolved = false; 1237 break; 1238 } 1239 1240 if ((self && var_data != hist_data) || 1241 (!self && var_data == hist_data)) 1242 continue; 1243 1244 var_elt = tracing_map_lookup(var_data->map, key); 1245 if (!var_elt) { 1246 resolved = false; 1247 break; 1248 } 1249 1250 if (!tracing_map_var_set(var_elt, var_idx)) { 1251 resolved = false; 1252 break; 1253 } 1254 1255 if (self || !hist_field->read_once) 1256 var_val = tracing_map_read_var(var_elt, var_idx); 1257 else 1258 var_val = tracing_map_read_var_once(var_elt, var_idx); 1259 1260 var_ref_vals[i] = var_val; 1261 } 1262 1263 return resolved; 1264 } 1265 1266 static const char *hist_field_name(struct hist_field *field, 1267 unsigned int level) 1268 { 1269 const char *field_name = ""; 1270 1271 if (level > 1) 1272 return field_name; 1273 1274 if (field->field) 1275 field_name = field->field->name; 1276 else if (field->flags & HIST_FIELD_FL_LOG2 || 1277 field->flags & HIST_FIELD_FL_ALIAS || 1278 field->flags & HIST_FIELD_FL_BUCKET) 1279 field_name = hist_field_name(field->operands[0], ++level); 1280 else if (field->flags & HIST_FIELD_FL_CPU) 1281 field_name = "common_cpu"; 1282 else if (field->flags & HIST_FIELD_FL_EXPR || 1283 field->flags & HIST_FIELD_FL_VAR_REF) { 1284 if (field->system) { 1285 static char full_name[MAX_FILTER_STR_VAL]; 1286 1287 strcat(full_name, field->system); 1288 strcat(full_name, "."); 1289 strcat(full_name, field->event_name); 1290 strcat(full_name, "."); 1291 strcat(full_name, field->name); 1292 field_name = full_name; 1293 } else 1294 field_name = field->name; 1295 } else if (field->flags & HIST_FIELD_FL_TIMESTAMP) 1296 field_name = "common_timestamp"; 1297 1298 if (field_name == NULL) 1299 field_name = ""; 1300 1301 return field_name; 1302 } 1303 1304 static hist_field_fn_t select_value_fn(int field_size, int field_is_signed) 1305 { 1306 hist_field_fn_t fn = NULL; 1307 1308 switch (field_size) { 1309 case 8: 1310 if (field_is_signed) 1311 fn = hist_field_s64; 1312 else 1313 fn = hist_field_u64; 1314 break; 1315 case 4: 1316 if (field_is_signed) 1317 fn = hist_field_s32; 1318 else 1319 fn = hist_field_u32; 1320 break; 1321 case 2: 1322 if (field_is_signed) 1323 fn = hist_field_s16; 1324 else 1325 fn = hist_field_u16; 1326 break; 1327 case 1: 1328 if (field_is_signed) 1329 fn = hist_field_s8; 1330 else 1331 fn = hist_field_u8; 1332 break; 1333 } 1334 1335 return fn; 1336 } 1337 1338 static int parse_map_size(char *str) 1339 { 1340 unsigned long size, map_bits; 1341 int ret; 1342 1343 ret = kstrtoul(str, 0, &size); 1344 if (ret) 1345 goto out; 1346 1347 map_bits = ilog2(roundup_pow_of_two(size)); 1348 if (map_bits < TRACING_MAP_BITS_MIN || 1349 map_bits > TRACING_MAP_BITS_MAX) 1350 ret = -EINVAL; 1351 else 1352 ret = map_bits; 1353 out: 1354 return ret; 1355 } 1356 1357 static void destroy_hist_trigger_attrs(struct hist_trigger_attrs *attrs) 1358 { 1359 unsigned int i; 1360 1361 if (!attrs) 1362 return; 1363 1364 for (i = 0; i < attrs->n_assignments; i++) 1365 kfree(attrs->assignment_str[i]); 1366 1367 for (i = 0; i < attrs->n_actions; i++) 1368 kfree(attrs->action_str[i]); 1369 1370 kfree(attrs->name); 1371 kfree(attrs->sort_key_str); 1372 kfree(attrs->keys_str); 1373 kfree(attrs->vals_str); 1374 kfree(attrs->clock); 1375 kfree(attrs); 1376 } 1377 1378 static int parse_action(char *str, struct hist_trigger_attrs *attrs) 1379 { 1380 int ret = -EINVAL; 1381 1382 if (attrs->n_actions >= HIST_ACTIONS_MAX) 1383 return ret; 1384 1385 if ((str_has_prefix(str, "onmatch(")) || 1386 (str_has_prefix(str, "onmax(")) || 1387 (str_has_prefix(str, "onchange("))) { 1388 attrs->action_str[attrs->n_actions] = kstrdup(str, GFP_KERNEL); 1389 if (!attrs->action_str[attrs->n_actions]) { 1390 ret = -ENOMEM; 1391 return ret; 1392 } 1393 attrs->n_actions++; 1394 ret = 0; 1395 } 1396 return ret; 1397 } 1398 1399 static int parse_assignment(struct trace_array *tr, 1400 char *str, struct hist_trigger_attrs *attrs) 1401 { 1402 int len, ret = 0; 1403 1404 if ((len = str_has_prefix(str, "key=")) || 1405 (len = str_has_prefix(str, "keys="))) { 1406 attrs->keys_str = kstrdup(str + len, GFP_KERNEL); 1407 if (!attrs->keys_str) { 1408 ret = -ENOMEM; 1409 goto out; 1410 } 1411 } else if ((len = str_has_prefix(str, "val=")) || 1412 (len = str_has_prefix(str, "vals=")) || 1413 (len = str_has_prefix(str, "values="))) { 1414 attrs->vals_str = kstrdup(str + len, GFP_KERNEL); 1415 if (!attrs->vals_str) { 1416 ret = -ENOMEM; 1417 goto out; 1418 } 1419 } else if ((len = str_has_prefix(str, "sort="))) { 1420 attrs->sort_key_str = kstrdup(str + len, GFP_KERNEL); 1421 if (!attrs->sort_key_str) { 1422 ret = -ENOMEM; 1423 goto out; 1424 } 1425 } else if (str_has_prefix(str, "name=")) { 1426 attrs->name = kstrdup(str, GFP_KERNEL); 1427 if (!attrs->name) { 1428 ret = -ENOMEM; 1429 goto out; 1430 } 1431 } else if ((len = str_has_prefix(str, "clock="))) { 1432 str += len; 1433 1434 str = strstrip(str); 1435 attrs->clock = kstrdup(str, GFP_KERNEL); 1436 if (!attrs->clock) { 1437 ret = -ENOMEM; 1438 goto out; 1439 } 1440 } else if ((len = str_has_prefix(str, "size="))) { 1441 int map_bits = parse_map_size(str + len); 1442 1443 if (map_bits < 0) { 1444 ret = map_bits; 1445 goto out; 1446 } 1447 attrs->map_bits = map_bits; 1448 } else { 1449 char *assignment; 1450 1451 if (attrs->n_assignments == TRACING_MAP_VARS_MAX) { 1452 hist_err(tr, HIST_ERR_TOO_MANY_VARS, errpos(str)); 1453 ret = -EINVAL; 1454 goto out; 1455 } 1456 1457 assignment = kstrdup(str, GFP_KERNEL); 1458 if (!assignment) { 1459 ret = -ENOMEM; 1460 goto out; 1461 } 1462 1463 attrs->assignment_str[attrs->n_assignments++] = assignment; 1464 } 1465 out: 1466 return ret; 1467 } 1468 1469 static struct hist_trigger_attrs * 1470 parse_hist_trigger_attrs(struct trace_array *tr, char *trigger_str) 1471 { 1472 struct hist_trigger_attrs *attrs; 1473 int ret = 0; 1474 1475 attrs = kzalloc(sizeof(*attrs), GFP_KERNEL); 1476 if (!attrs) 1477 return ERR_PTR(-ENOMEM); 1478 1479 while (trigger_str) { 1480 char *str = strsep(&trigger_str, ":"); 1481 char *rhs; 1482 1483 rhs = strchr(str, '='); 1484 if (rhs) { 1485 if (!strlen(++rhs)) { 1486 ret = -EINVAL; 1487 hist_err(tr, HIST_ERR_EMPTY_ASSIGNMENT, errpos(str)); 1488 goto free; 1489 } 1490 ret = parse_assignment(tr, str, attrs); 1491 if (ret) 1492 goto free; 1493 } else if (strcmp(str, "pause") == 0) 1494 attrs->pause = true; 1495 else if ((strcmp(str, "cont") == 0) || 1496 (strcmp(str, "continue") == 0)) 1497 attrs->cont = true; 1498 else if (strcmp(str, "clear") == 0) 1499 attrs->clear = true; 1500 else { 1501 ret = parse_action(str, attrs); 1502 if (ret) 1503 goto free; 1504 } 1505 } 1506 1507 if (!attrs->keys_str) { 1508 ret = -EINVAL; 1509 goto free; 1510 } 1511 1512 if (!attrs->clock) { 1513 attrs->clock = kstrdup("global", GFP_KERNEL); 1514 if (!attrs->clock) { 1515 ret = -ENOMEM; 1516 goto free; 1517 } 1518 } 1519 1520 return attrs; 1521 free: 1522 destroy_hist_trigger_attrs(attrs); 1523 1524 return ERR_PTR(ret); 1525 } 1526 1527 static inline void save_comm(char *comm, struct task_struct *task) 1528 { 1529 if (!task->pid) { 1530 strcpy(comm, "<idle>"); 1531 return; 1532 } 1533 1534 if (WARN_ON_ONCE(task->pid < 0)) { 1535 strcpy(comm, "<XXX>"); 1536 return; 1537 } 1538 1539 strncpy(comm, task->comm, TASK_COMM_LEN); 1540 } 1541 1542 static void hist_elt_data_free(struct hist_elt_data *elt_data) 1543 { 1544 unsigned int i; 1545 1546 for (i = 0; i < elt_data->n_field_var_str; i++) 1547 kfree(elt_data->field_var_str[i]); 1548 1549 kfree(elt_data->field_var_str); 1550 1551 kfree(elt_data->comm); 1552 kfree(elt_data); 1553 } 1554 1555 static void hist_trigger_elt_data_free(struct tracing_map_elt *elt) 1556 { 1557 struct hist_elt_data *elt_data = elt->private_data; 1558 1559 hist_elt_data_free(elt_data); 1560 } 1561 1562 static int hist_trigger_elt_data_alloc(struct tracing_map_elt *elt) 1563 { 1564 struct hist_trigger_data *hist_data = elt->map->private_data; 1565 unsigned int size = TASK_COMM_LEN; 1566 struct hist_elt_data *elt_data; 1567 struct hist_field *hist_field; 1568 unsigned int i, n_str; 1569 1570 elt_data = kzalloc(sizeof(*elt_data), GFP_KERNEL); 1571 if (!elt_data) 1572 return -ENOMEM; 1573 1574 for_each_hist_field(i, hist_data) { 1575 hist_field = hist_data->fields[i]; 1576 1577 if (hist_field->flags & HIST_FIELD_FL_EXECNAME) { 1578 elt_data->comm = kzalloc(size, GFP_KERNEL); 1579 if (!elt_data->comm) { 1580 kfree(elt_data); 1581 return -ENOMEM; 1582 } 1583 break; 1584 } 1585 } 1586 1587 n_str = hist_data->n_field_var_str + hist_data->n_save_var_str + 1588 hist_data->n_var_str; 1589 if (n_str > SYNTH_FIELDS_MAX) { 1590 hist_elt_data_free(elt_data); 1591 return -EINVAL; 1592 } 1593 1594 BUILD_BUG_ON(STR_VAR_LEN_MAX & (sizeof(u64) - 1)); 1595 1596 size = STR_VAR_LEN_MAX; 1597 1598 elt_data->field_var_str = kcalloc(n_str, sizeof(char *), GFP_KERNEL); 1599 if (!elt_data->field_var_str) { 1600 hist_elt_data_free(elt_data); 1601 return -EINVAL; 1602 } 1603 elt_data->n_field_var_str = n_str; 1604 1605 for (i = 0; i < n_str; i++) { 1606 elt_data->field_var_str[i] = kzalloc(size, GFP_KERNEL); 1607 if (!elt_data->field_var_str[i]) { 1608 hist_elt_data_free(elt_data); 1609 return -ENOMEM; 1610 } 1611 } 1612 1613 elt->private_data = elt_data; 1614 1615 return 0; 1616 } 1617 1618 static void hist_trigger_elt_data_init(struct tracing_map_elt *elt) 1619 { 1620 struct hist_elt_data *elt_data = elt->private_data; 1621 1622 if (elt_data->comm) 1623 save_comm(elt_data->comm, current); 1624 } 1625 1626 static const struct tracing_map_ops hist_trigger_elt_data_ops = { 1627 .elt_alloc = hist_trigger_elt_data_alloc, 1628 .elt_free = hist_trigger_elt_data_free, 1629 .elt_init = hist_trigger_elt_data_init, 1630 }; 1631 1632 static const char *get_hist_field_flags(struct hist_field *hist_field) 1633 { 1634 const char *flags_str = NULL; 1635 1636 if (hist_field->flags & HIST_FIELD_FL_HEX) 1637 flags_str = "hex"; 1638 else if (hist_field->flags & HIST_FIELD_FL_SYM) 1639 flags_str = "sym"; 1640 else if (hist_field->flags & HIST_FIELD_FL_SYM_OFFSET) 1641 flags_str = "sym-offset"; 1642 else if (hist_field->flags & HIST_FIELD_FL_EXECNAME) 1643 flags_str = "execname"; 1644 else if (hist_field->flags & HIST_FIELD_FL_SYSCALL) 1645 flags_str = "syscall"; 1646 else if (hist_field->flags & HIST_FIELD_FL_LOG2) 1647 flags_str = "log2"; 1648 else if (hist_field->flags & HIST_FIELD_FL_BUCKET) 1649 flags_str = "buckets"; 1650 else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP_USECS) 1651 flags_str = "usecs"; 1652 1653 return flags_str; 1654 } 1655 1656 static void expr_field_str(struct hist_field *field, char *expr) 1657 { 1658 if (field->flags & HIST_FIELD_FL_VAR_REF) 1659 strcat(expr, "$"); 1660 else if (field->flags & HIST_FIELD_FL_CONST) { 1661 char str[HIST_CONST_DIGITS_MAX]; 1662 1663 snprintf(str, HIST_CONST_DIGITS_MAX, "%llu", field->constant); 1664 strcat(expr, str); 1665 } 1666 1667 strcat(expr, hist_field_name(field, 0)); 1668 1669 if (field->flags && !(field->flags & HIST_FIELD_FL_VAR_REF)) { 1670 const char *flags_str = get_hist_field_flags(field); 1671 1672 if (flags_str) { 1673 strcat(expr, "."); 1674 strcat(expr, flags_str); 1675 } 1676 } 1677 } 1678 1679 static char *expr_str(struct hist_field *field, unsigned int level) 1680 { 1681 char *expr; 1682 1683 if (level > 1) 1684 return NULL; 1685 1686 expr = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL); 1687 if (!expr) 1688 return NULL; 1689 1690 if (!field->operands[0]) { 1691 expr_field_str(field, expr); 1692 return expr; 1693 } 1694 1695 if (field->operator == FIELD_OP_UNARY_MINUS) { 1696 char *subexpr; 1697 1698 strcat(expr, "-("); 1699 subexpr = expr_str(field->operands[0], ++level); 1700 if (!subexpr) { 1701 kfree(expr); 1702 return NULL; 1703 } 1704 strcat(expr, subexpr); 1705 strcat(expr, ")"); 1706 1707 kfree(subexpr); 1708 1709 return expr; 1710 } 1711 1712 expr_field_str(field->operands[0], expr); 1713 1714 switch (field->operator) { 1715 case FIELD_OP_MINUS: 1716 strcat(expr, "-"); 1717 break; 1718 case FIELD_OP_PLUS: 1719 strcat(expr, "+"); 1720 break; 1721 case FIELD_OP_DIV: 1722 strcat(expr, "/"); 1723 break; 1724 case FIELD_OP_MULT: 1725 strcat(expr, "*"); 1726 break; 1727 default: 1728 kfree(expr); 1729 return NULL; 1730 } 1731 1732 expr_field_str(field->operands[1], expr); 1733 1734 return expr; 1735 } 1736 1737 /* 1738 * If field_op != FIELD_OP_NONE, *sep points to the root operator 1739 * of the expression tree to be evaluated. 1740 */ 1741 static int contains_operator(char *str, char **sep) 1742 { 1743 enum field_op_id field_op = FIELD_OP_NONE; 1744 char *minus_op, *plus_op, *div_op, *mult_op; 1745 1746 1747 /* 1748 * Report the last occurrence of the operators first, so that the 1749 * expression is evaluated left to right. This is important since 1750 * subtraction and division are not associative. 1751 * 1752 * e.g 1753 * 64/8/4/2 is 1, i.e 64/8/4/2 = ((64/8)/4)/2 1754 * 14-7-5-2 is 0, i.e 14-7-5-2 = ((14-7)-5)-2 1755 */ 1756 1757 /* 1758 * First, find lower precedence addition and subtraction 1759 * since the expression will be evaluated recursively. 1760 */ 1761 minus_op = strrchr(str, '-'); 1762 if (minus_op) { 1763 /* 1764 * Unary minus is not supported in sub-expressions. If 1765 * present, it is always the next root operator. 1766 */ 1767 if (minus_op == str) { 1768 field_op = FIELD_OP_UNARY_MINUS; 1769 goto out; 1770 } 1771 1772 field_op = FIELD_OP_MINUS; 1773 } 1774 1775 plus_op = strrchr(str, '+'); 1776 if (plus_op || minus_op) { 1777 /* 1778 * For operators of the same precedence use to rightmost as the 1779 * root, so that the expression is evaluated left to right. 1780 */ 1781 if (plus_op > minus_op) 1782 field_op = FIELD_OP_PLUS; 1783 goto out; 1784 } 1785 1786 /* 1787 * Multiplication and division have higher precedence than addition and 1788 * subtraction. 1789 */ 1790 div_op = strrchr(str, '/'); 1791 if (div_op) 1792 field_op = FIELD_OP_DIV; 1793 1794 mult_op = strrchr(str, '*'); 1795 /* 1796 * For operators of the same precedence use to rightmost as the 1797 * root, so that the expression is evaluated left to right. 1798 */ 1799 if (mult_op > div_op) 1800 field_op = FIELD_OP_MULT; 1801 1802 out: 1803 if (sep) { 1804 switch (field_op) { 1805 case FIELD_OP_UNARY_MINUS: 1806 case FIELD_OP_MINUS: 1807 *sep = minus_op; 1808 break; 1809 case FIELD_OP_PLUS: 1810 *sep = plus_op; 1811 break; 1812 case FIELD_OP_DIV: 1813 *sep = div_op; 1814 break; 1815 case FIELD_OP_MULT: 1816 *sep = mult_op; 1817 break; 1818 case FIELD_OP_NONE: 1819 default: 1820 *sep = NULL; 1821 break; 1822 } 1823 } 1824 1825 return field_op; 1826 } 1827 1828 static void get_hist_field(struct hist_field *hist_field) 1829 { 1830 hist_field->ref++; 1831 } 1832 1833 static void __destroy_hist_field(struct hist_field *hist_field) 1834 { 1835 if (--hist_field->ref > 1) 1836 return; 1837 1838 kfree(hist_field->var.name); 1839 kfree(hist_field->name); 1840 1841 /* Can likely be a const */ 1842 kfree_const(hist_field->type); 1843 1844 kfree(hist_field->system); 1845 kfree(hist_field->event_name); 1846 1847 kfree(hist_field); 1848 } 1849 1850 static void destroy_hist_field(struct hist_field *hist_field, 1851 unsigned int level) 1852 { 1853 unsigned int i; 1854 1855 if (level > 3) 1856 return; 1857 1858 if (!hist_field) 1859 return; 1860 1861 if (hist_field->flags & HIST_FIELD_FL_VAR_REF) 1862 return; /* var refs will be destroyed separately */ 1863 1864 for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++) 1865 destroy_hist_field(hist_field->operands[i], level + 1); 1866 1867 __destroy_hist_field(hist_field); 1868 } 1869 1870 static struct hist_field *create_hist_field(struct hist_trigger_data *hist_data, 1871 struct ftrace_event_field *field, 1872 unsigned long flags, 1873 char *var_name) 1874 { 1875 struct hist_field *hist_field; 1876 1877 if (field && is_function_field(field)) 1878 return NULL; 1879 1880 hist_field = kzalloc(sizeof(struct hist_field), GFP_KERNEL); 1881 if (!hist_field) 1882 return NULL; 1883 1884 hist_field->ref = 1; 1885 1886 hist_field->hist_data = hist_data; 1887 1888 if (flags & HIST_FIELD_FL_EXPR || flags & HIST_FIELD_FL_ALIAS) 1889 goto out; /* caller will populate */ 1890 1891 if (flags & HIST_FIELD_FL_VAR_REF) { 1892 hist_field->fn = hist_field_var_ref; 1893 goto out; 1894 } 1895 1896 if (flags & HIST_FIELD_FL_HITCOUNT) { 1897 hist_field->fn = hist_field_counter; 1898 hist_field->size = sizeof(u64); 1899 hist_field->type = "u64"; 1900 goto out; 1901 } 1902 1903 if (flags & HIST_FIELD_FL_CONST) { 1904 hist_field->fn = hist_field_const; 1905 hist_field->size = sizeof(u64); 1906 hist_field->type = kstrdup("u64", GFP_KERNEL); 1907 if (!hist_field->type) 1908 goto free; 1909 goto out; 1910 } 1911 1912 if (flags & HIST_FIELD_FL_STACKTRACE) { 1913 hist_field->fn = hist_field_none; 1914 goto out; 1915 } 1916 1917 if (flags & (HIST_FIELD_FL_LOG2 | HIST_FIELD_FL_BUCKET)) { 1918 unsigned long fl = flags & ~(HIST_FIELD_FL_LOG2 | HIST_FIELD_FL_BUCKET); 1919 hist_field->fn = flags & HIST_FIELD_FL_LOG2 ? hist_field_log2 : 1920 hist_field_bucket; 1921 hist_field->operands[0] = create_hist_field(hist_data, field, fl, NULL); 1922 hist_field->size = hist_field->operands[0]->size; 1923 hist_field->type = kstrdup_const(hist_field->operands[0]->type, GFP_KERNEL); 1924 if (!hist_field->type) 1925 goto free; 1926 goto out; 1927 } 1928 1929 if (flags & HIST_FIELD_FL_TIMESTAMP) { 1930 hist_field->fn = hist_field_timestamp; 1931 hist_field->size = sizeof(u64); 1932 hist_field->type = "u64"; 1933 goto out; 1934 } 1935 1936 if (flags & HIST_FIELD_FL_CPU) { 1937 hist_field->fn = hist_field_cpu; 1938 hist_field->size = sizeof(int); 1939 hist_field->type = "unsigned int"; 1940 goto out; 1941 } 1942 1943 if (WARN_ON_ONCE(!field)) 1944 goto out; 1945 1946 /* Pointers to strings are just pointers and dangerous to dereference */ 1947 if (is_string_field(field) && 1948 (field->filter_type != FILTER_PTR_STRING)) { 1949 flags |= HIST_FIELD_FL_STRING; 1950 1951 hist_field->size = MAX_FILTER_STR_VAL; 1952 hist_field->type = kstrdup_const(field->type, GFP_KERNEL); 1953 if (!hist_field->type) 1954 goto free; 1955 1956 if (field->filter_type == FILTER_STATIC_STRING) 1957 hist_field->fn = hist_field_string; 1958 else if (field->filter_type == FILTER_DYN_STRING) 1959 hist_field->fn = hist_field_dynstring; 1960 else 1961 hist_field->fn = hist_field_pstring; 1962 } else { 1963 hist_field->size = field->size; 1964 hist_field->is_signed = field->is_signed; 1965 hist_field->type = kstrdup_const(field->type, GFP_KERNEL); 1966 if (!hist_field->type) 1967 goto free; 1968 1969 hist_field->fn = select_value_fn(field->size, 1970 field->is_signed); 1971 if (!hist_field->fn) { 1972 destroy_hist_field(hist_field, 0); 1973 return NULL; 1974 } 1975 } 1976 out: 1977 hist_field->field = field; 1978 hist_field->flags = flags; 1979 1980 if (var_name) { 1981 hist_field->var.name = kstrdup(var_name, GFP_KERNEL); 1982 if (!hist_field->var.name) 1983 goto free; 1984 } 1985 1986 return hist_field; 1987 free: 1988 destroy_hist_field(hist_field, 0); 1989 return NULL; 1990 } 1991 1992 static void destroy_hist_fields(struct hist_trigger_data *hist_data) 1993 { 1994 unsigned int i; 1995 1996 for (i = 0; i < HIST_FIELDS_MAX; i++) { 1997 if (hist_data->fields[i]) { 1998 destroy_hist_field(hist_data->fields[i], 0); 1999 hist_data->fields[i] = NULL; 2000 } 2001 } 2002 2003 for (i = 0; i < hist_data->n_var_refs; i++) { 2004 WARN_ON(!(hist_data->var_refs[i]->flags & HIST_FIELD_FL_VAR_REF)); 2005 __destroy_hist_field(hist_data->var_refs[i]); 2006 hist_data->var_refs[i] = NULL; 2007 } 2008 } 2009 2010 static int init_var_ref(struct hist_field *ref_field, 2011 struct hist_field *var_field, 2012 char *system, char *event_name) 2013 { 2014 int err = 0; 2015 2016 ref_field->var.idx = var_field->var.idx; 2017 ref_field->var.hist_data = var_field->hist_data; 2018 ref_field->size = var_field->size; 2019 ref_field->is_signed = var_field->is_signed; 2020 ref_field->flags |= var_field->flags & 2021 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS); 2022 2023 if (system) { 2024 ref_field->system = kstrdup(system, GFP_KERNEL); 2025 if (!ref_field->system) 2026 return -ENOMEM; 2027 } 2028 2029 if (event_name) { 2030 ref_field->event_name = kstrdup(event_name, GFP_KERNEL); 2031 if (!ref_field->event_name) { 2032 err = -ENOMEM; 2033 goto free; 2034 } 2035 } 2036 2037 if (var_field->var.name) { 2038 ref_field->name = kstrdup(var_field->var.name, GFP_KERNEL); 2039 if (!ref_field->name) { 2040 err = -ENOMEM; 2041 goto free; 2042 } 2043 } else if (var_field->name) { 2044 ref_field->name = kstrdup(var_field->name, GFP_KERNEL); 2045 if (!ref_field->name) { 2046 err = -ENOMEM; 2047 goto free; 2048 } 2049 } 2050 2051 ref_field->type = kstrdup_const(var_field->type, GFP_KERNEL); 2052 if (!ref_field->type) { 2053 err = -ENOMEM; 2054 goto free; 2055 } 2056 out: 2057 return err; 2058 free: 2059 kfree(ref_field->system); 2060 kfree(ref_field->event_name); 2061 kfree(ref_field->name); 2062 2063 goto out; 2064 } 2065 2066 static int find_var_ref_idx(struct hist_trigger_data *hist_data, 2067 struct hist_field *var_field) 2068 { 2069 struct hist_field *ref_field; 2070 int i; 2071 2072 for (i = 0; i < hist_data->n_var_refs; i++) { 2073 ref_field = hist_data->var_refs[i]; 2074 if (ref_field->var.idx == var_field->var.idx && 2075 ref_field->var.hist_data == var_field->hist_data) 2076 return i; 2077 } 2078 2079 return -ENOENT; 2080 } 2081 2082 /** 2083 * create_var_ref - Create a variable reference and attach it to trigger 2084 * @hist_data: The trigger that will be referencing the variable 2085 * @var_field: The VAR field to create a reference to 2086 * @system: The optional system string 2087 * @event_name: The optional event_name string 2088 * 2089 * Given a variable hist_field, create a VAR_REF hist_field that 2090 * represents a reference to it. 2091 * 2092 * This function also adds the reference to the trigger that 2093 * now references the variable. 2094 * 2095 * Return: The VAR_REF field if successful, NULL if not 2096 */ 2097 static struct hist_field *create_var_ref(struct hist_trigger_data *hist_data, 2098 struct hist_field *var_field, 2099 char *system, char *event_name) 2100 { 2101 unsigned long flags = HIST_FIELD_FL_VAR_REF; 2102 struct hist_field *ref_field; 2103 int i; 2104 2105 /* Check if the variable already exists */ 2106 for (i = 0; i < hist_data->n_var_refs; i++) { 2107 ref_field = hist_data->var_refs[i]; 2108 if (ref_field->var.idx == var_field->var.idx && 2109 ref_field->var.hist_data == var_field->hist_data) { 2110 get_hist_field(ref_field); 2111 return ref_field; 2112 } 2113 } 2114 2115 ref_field = create_hist_field(var_field->hist_data, NULL, flags, NULL); 2116 if (ref_field) { 2117 if (init_var_ref(ref_field, var_field, system, event_name)) { 2118 destroy_hist_field(ref_field, 0); 2119 return NULL; 2120 } 2121 2122 hist_data->var_refs[hist_data->n_var_refs] = ref_field; 2123 ref_field->var_ref_idx = hist_data->n_var_refs++; 2124 } 2125 2126 return ref_field; 2127 } 2128 2129 static bool is_var_ref(char *var_name) 2130 { 2131 if (!var_name || strlen(var_name) < 2 || var_name[0] != '$') 2132 return false; 2133 2134 return true; 2135 } 2136 2137 static char *field_name_from_var(struct hist_trigger_data *hist_data, 2138 char *var_name) 2139 { 2140 char *name, *field; 2141 unsigned int i; 2142 2143 for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) { 2144 name = hist_data->attrs->var_defs.name[i]; 2145 2146 if (strcmp(var_name, name) == 0) { 2147 field = hist_data->attrs->var_defs.expr[i]; 2148 if (contains_operator(field, NULL) || is_var_ref(field)) 2149 continue; 2150 return field; 2151 } 2152 } 2153 2154 return NULL; 2155 } 2156 2157 static char *local_field_var_ref(struct hist_trigger_data *hist_data, 2158 char *system, char *event_name, 2159 char *var_name) 2160 { 2161 struct trace_event_call *call; 2162 2163 if (system && event_name) { 2164 call = hist_data->event_file->event_call; 2165 2166 if (strcmp(system, call->class->system) != 0) 2167 return NULL; 2168 2169 if (strcmp(event_name, trace_event_name(call)) != 0) 2170 return NULL; 2171 } 2172 2173 if (!!system != !!event_name) 2174 return NULL; 2175 2176 if (!is_var_ref(var_name)) 2177 return NULL; 2178 2179 var_name++; 2180 2181 return field_name_from_var(hist_data, var_name); 2182 } 2183 2184 static struct hist_field *parse_var_ref(struct hist_trigger_data *hist_data, 2185 char *system, char *event_name, 2186 char *var_name) 2187 { 2188 struct hist_field *var_field = NULL, *ref_field = NULL; 2189 struct trace_array *tr = hist_data->event_file->tr; 2190 2191 if (!is_var_ref(var_name)) 2192 return NULL; 2193 2194 var_name++; 2195 2196 var_field = find_event_var(hist_data, system, event_name, var_name); 2197 if (var_field) 2198 ref_field = create_var_ref(hist_data, var_field, 2199 system, event_name); 2200 2201 if (!ref_field) 2202 hist_err(tr, HIST_ERR_VAR_NOT_FOUND, errpos(var_name)); 2203 2204 return ref_field; 2205 } 2206 2207 static struct ftrace_event_field * 2208 parse_field(struct hist_trigger_data *hist_data, struct trace_event_file *file, 2209 char *field_str, unsigned long *flags, unsigned long *buckets) 2210 { 2211 struct ftrace_event_field *field = NULL; 2212 char *field_name, *modifier, *str; 2213 struct trace_array *tr = file->tr; 2214 2215 modifier = str = kstrdup(field_str, GFP_KERNEL); 2216 if (!modifier) 2217 return ERR_PTR(-ENOMEM); 2218 2219 field_name = strsep(&modifier, "."); 2220 if (modifier) { 2221 if (strcmp(modifier, "hex") == 0) 2222 *flags |= HIST_FIELD_FL_HEX; 2223 else if (strcmp(modifier, "sym") == 0) 2224 *flags |= HIST_FIELD_FL_SYM; 2225 /* 2226 * 'sym-offset' occurrences in the trigger string are modified 2227 * to 'symXoffset' to simplify arithmetic expression parsing. 2228 */ 2229 else if (strcmp(modifier, "symXoffset") == 0) 2230 *flags |= HIST_FIELD_FL_SYM_OFFSET; 2231 else if ((strcmp(modifier, "execname") == 0) && 2232 (strcmp(field_name, "common_pid") == 0)) 2233 *flags |= HIST_FIELD_FL_EXECNAME; 2234 else if (strcmp(modifier, "syscall") == 0) 2235 *flags |= HIST_FIELD_FL_SYSCALL; 2236 else if (strcmp(modifier, "log2") == 0) 2237 *flags |= HIST_FIELD_FL_LOG2; 2238 else if (strcmp(modifier, "usecs") == 0) 2239 *flags |= HIST_FIELD_FL_TIMESTAMP_USECS; 2240 else if (strncmp(modifier, "bucket", 6) == 0) { 2241 int ret; 2242 2243 modifier += 6; 2244 2245 if (*modifier == 's') 2246 modifier++; 2247 if (*modifier != '=') 2248 goto error; 2249 modifier++; 2250 ret = kstrtoul(modifier, 0, buckets); 2251 if (ret || !(*buckets)) 2252 goto error; 2253 *flags |= HIST_FIELD_FL_BUCKET; 2254 } else { 2255 error: 2256 hist_err(tr, HIST_ERR_BAD_FIELD_MODIFIER, errpos(modifier)); 2257 field = ERR_PTR(-EINVAL); 2258 goto out; 2259 } 2260 } 2261 2262 if (strcmp(field_name, "common_timestamp") == 0) { 2263 *flags |= HIST_FIELD_FL_TIMESTAMP; 2264 hist_data->enable_timestamps = true; 2265 if (*flags & HIST_FIELD_FL_TIMESTAMP_USECS) 2266 hist_data->attrs->ts_in_usecs = true; 2267 } else if (strcmp(field_name, "common_cpu") == 0) 2268 *flags |= HIST_FIELD_FL_CPU; 2269 else { 2270 field = trace_find_event_field(file->event_call, field_name); 2271 if (!field || !field->size) { 2272 /* 2273 * For backward compatibility, if field_name 2274 * was "cpu", then we treat this the same as 2275 * common_cpu. 2276 */ 2277 if (strcmp(field_name, "cpu") == 0) { 2278 *flags |= HIST_FIELD_FL_CPU; 2279 } else { 2280 hist_err(tr, HIST_ERR_FIELD_NOT_FOUND, 2281 errpos(field_name)); 2282 field = ERR_PTR(-EINVAL); 2283 goto out; 2284 } 2285 } 2286 } 2287 out: 2288 kfree(str); 2289 2290 return field; 2291 } 2292 2293 static struct hist_field *create_alias(struct hist_trigger_data *hist_data, 2294 struct hist_field *var_ref, 2295 char *var_name) 2296 { 2297 struct hist_field *alias = NULL; 2298 unsigned long flags = HIST_FIELD_FL_ALIAS | HIST_FIELD_FL_VAR; 2299 2300 alias = create_hist_field(hist_data, NULL, flags, var_name); 2301 if (!alias) 2302 return NULL; 2303 2304 alias->fn = var_ref->fn; 2305 alias->operands[0] = var_ref; 2306 2307 if (init_var_ref(alias, var_ref, var_ref->system, var_ref->event_name)) { 2308 destroy_hist_field(alias, 0); 2309 return NULL; 2310 } 2311 2312 alias->var_ref_idx = var_ref->var_ref_idx; 2313 2314 return alias; 2315 } 2316 2317 static struct hist_field *parse_const(struct hist_trigger_data *hist_data, 2318 char *str, char *var_name, 2319 unsigned long *flags) 2320 { 2321 struct trace_array *tr = hist_data->event_file->tr; 2322 struct hist_field *field = NULL; 2323 u64 constant; 2324 2325 if (kstrtoull(str, 0, &constant)) { 2326 hist_err(tr, HIST_ERR_EXPECT_NUMBER, errpos(str)); 2327 return NULL; 2328 } 2329 2330 *flags |= HIST_FIELD_FL_CONST; 2331 field = create_hist_field(hist_data, NULL, *flags, var_name); 2332 if (!field) 2333 return NULL; 2334 2335 field->constant = constant; 2336 2337 return field; 2338 } 2339 2340 static struct hist_field *parse_atom(struct hist_trigger_data *hist_data, 2341 struct trace_event_file *file, char *str, 2342 unsigned long *flags, char *var_name) 2343 { 2344 char *s, *ref_system = NULL, *ref_event = NULL, *ref_var = str; 2345 struct ftrace_event_field *field = NULL; 2346 struct hist_field *hist_field = NULL; 2347 unsigned long buckets = 0; 2348 int ret = 0; 2349 2350 if (isdigit(str[0])) { 2351 hist_field = parse_const(hist_data, str, var_name, flags); 2352 if (!hist_field) { 2353 ret = -EINVAL; 2354 goto out; 2355 } 2356 return hist_field; 2357 } 2358 2359 s = strchr(str, '.'); 2360 if (s) { 2361 s = strchr(++s, '.'); 2362 if (s) { 2363 ref_system = strsep(&str, "."); 2364 if (!str) { 2365 ret = -EINVAL; 2366 goto out; 2367 } 2368 ref_event = strsep(&str, "."); 2369 if (!str) { 2370 ret = -EINVAL; 2371 goto out; 2372 } 2373 ref_var = str; 2374 } 2375 } 2376 2377 s = local_field_var_ref(hist_data, ref_system, ref_event, ref_var); 2378 if (!s) { 2379 hist_field = parse_var_ref(hist_data, ref_system, 2380 ref_event, ref_var); 2381 if (hist_field) { 2382 if (var_name) { 2383 hist_field = create_alias(hist_data, hist_field, var_name); 2384 if (!hist_field) { 2385 ret = -ENOMEM; 2386 goto out; 2387 } 2388 } 2389 return hist_field; 2390 } 2391 } else 2392 str = s; 2393 2394 field = parse_field(hist_data, file, str, flags, &buckets); 2395 if (IS_ERR(field)) { 2396 ret = PTR_ERR(field); 2397 goto out; 2398 } 2399 2400 hist_field = create_hist_field(hist_data, field, *flags, var_name); 2401 if (!hist_field) { 2402 ret = -ENOMEM; 2403 goto out; 2404 } 2405 hist_field->buckets = buckets; 2406 2407 return hist_field; 2408 out: 2409 return ERR_PTR(ret); 2410 } 2411 2412 static struct hist_field *parse_expr(struct hist_trigger_data *hist_data, 2413 struct trace_event_file *file, 2414 char *str, unsigned long flags, 2415 char *var_name, unsigned int *n_subexprs); 2416 2417 static struct hist_field *parse_unary(struct hist_trigger_data *hist_data, 2418 struct trace_event_file *file, 2419 char *str, unsigned long flags, 2420 char *var_name, unsigned int *n_subexprs) 2421 { 2422 struct hist_field *operand1, *expr = NULL; 2423 unsigned long operand_flags; 2424 int ret = 0; 2425 char *s; 2426 2427 /* Unary minus operator, increment n_subexprs */ 2428 ++*n_subexprs; 2429 2430 /* we support only -(xxx) i.e. explicit parens required */ 2431 2432 if (*n_subexprs > 3) { 2433 hist_err(file->tr, HIST_ERR_TOO_MANY_SUBEXPR, errpos(str)); 2434 ret = -EINVAL; 2435 goto free; 2436 } 2437 2438 str++; /* skip leading '-' */ 2439 2440 s = strchr(str, '('); 2441 if (s) 2442 str++; 2443 else { 2444 ret = -EINVAL; 2445 goto free; 2446 } 2447 2448 s = strrchr(str, ')'); 2449 if (s) { 2450 /* unary minus not supported in sub-expressions */ 2451 if (*(s+1) != '\0') { 2452 hist_err(file->tr, HIST_ERR_UNARY_MINUS_SUBEXPR, 2453 errpos(str)); 2454 ret = -EINVAL; 2455 goto free; 2456 } 2457 *s = '\0'; 2458 } 2459 else { 2460 ret = -EINVAL; /* no closing ')' */ 2461 goto free; 2462 } 2463 2464 flags |= HIST_FIELD_FL_EXPR; 2465 expr = create_hist_field(hist_data, NULL, flags, var_name); 2466 if (!expr) { 2467 ret = -ENOMEM; 2468 goto free; 2469 } 2470 2471 operand_flags = 0; 2472 operand1 = parse_expr(hist_data, file, str, operand_flags, NULL, n_subexprs); 2473 if (IS_ERR(operand1)) { 2474 ret = PTR_ERR(operand1); 2475 goto free; 2476 } 2477 if (operand1->flags & HIST_FIELD_FL_STRING) { 2478 /* String type can not be the operand of unary operator. */ 2479 hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(str)); 2480 destroy_hist_field(operand1, 0); 2481 ret = -EINVAL; 2482 goto free; 2483 } 2484 2485 expr->flags |= operand1->flags & 2486 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS); 2487 expr->fn = hist_field_unary_minus; 2488 expr->operands[0] = operand1; 2489 expr->operator = FIELD_OP_UNARY_MINUS; 2490 expr->name = expr_str(expr, 0); 2491 expr->type = kstrdup_const(operand1->type, GFP_KERNEL); 2492 if (!expr->type) { 2493 ret = -ENOMEM; 2494 goto free; 2495 } 2496 2497 return expr; 2498 free: 2499 destroy_hist_field(expr, 0); 2500 return ERR_PTR(ret); 2501 } 2502 2503 /* 2504 * If the operands are var refs, return pointers the 2505 * variable(s) referenced in var1 and var2, else NULL. 2506 */ 2507 static int check_expr_operands(struct trace_array *tr, 2508 struct hist_field *operand1, 2509 struct hist_field *operand2, 2510 struct hist_field **var1, 2511 struct hist_field **var2) 2512 { 2513 unsigned long operand1_flags = operand1->flags; 2514 unsigned long operand2_flags = operand2->flags; 2515 2516 if ((operand1_flags & HIST_FIELD_FL_VAR_REF) || 2517 (operand1_flags & HIST_FIELD_FL_ALIAS)) { 2518 struct hist_field *var; 2519 2520 var = find_var_field(operand1->var.hist_data, operand1->name); 2521 if (!var) 2522 return -EINVAL; 2523 operand1_flags = var->flags; 2524 *var1 = var; 2525 } 2526 2527 if ((operand2_flags & HIST_FIELD_FL_VAR_REF) || 2528 (operand2_flags & HIST_FIELD_FL_ALIAS)) { 2529 struct hist_field *var; 2530 2531 var = find_var_field(operand2->var.hist_data, operand2->name); 2532 if (!var) 2533 return -EINVAL; 2534 operand2_flags = var->flags; 2535 *var2 = var; 2536 } 2537 2538 if ((operand1_flags & HIST_FIELD_FL_TIMESTAMP_USECS) != 2539 (operand2_flags & HIST_FIELD_FL_TIMESTAMP_USECS)) { 2540 hist_err(tr, HIST_ERR_TIMESTAMP_MISMATCH, 0); 2541 return -EINVAL; 2542 } 2543 2544 return 0; 2545 } 2546 2547 static struct hist_field *parse_expr(struct hist_trigger_data *hist_data, 2548 struct trace_event_file *file, 2549 char *str, unsigned long flags, 2550 char *var_name, unsigned int *n_subexprs) 2551 { 2552 struct hist_field *operand1 = NULL, *operand2 = NULL, *expr = NULL; 2553 struct hist_field *var1 = NULL, *var2 = NULL; 2554 unsigned long operand_flags, operand2_flags; 2555 int field_op, ret = -EINVAL; 2556 char *sep, *operand1_str; 2557 hist_field_fn_t op_fn; 2558 bool combine_consts; 2559 2560 if (*n_subexprs > 3) { 2561 hist_err(file->tr, HIST_ERR_TOO_MANY_SUBEXPR, errpos(str)); 2562 return ERR_PTR(-EINVAL); 2563 } 2564 2565 field_op = contains_operator(str, &sep); 2566 2567 if (field_op == FIELD_OP_NONE) 2568 return parse_atom(hist_data, file, str, &flags, var_name); 2569 2570 if (field_op == FIELD_OP_UNARY_MINUS) 2571 return parse_unary(hist_data, file, str, flags, var_name, n_subexprs); 2572 2573 /* Binary operator found, increment n_subexprs */ 2574 ++*n_subexprs; 2575 2576 /* Split the expression string at the root operator */ 2577 if (!sep) 2578 goto free; 2579 *sep = '\0'; 2580 operand1_str = str; 2581 str = sep+1; 2582 2583 if (!operand1_str || !str) 2584 goto free; 2585 2586 operand_flags = 0; 2587 2588 /* LHS of string is an expression e.g. a+b in a+b+c */ 2589 operand1 = parse_expr(hist_data, file, operand1_str, operand_flags, NULL, n_subexprs); 2590 if (IS_ERR(operand1)) { 2591 ret = PTR_ERR(operand1); 2592 operand1 = NULL; 2593 goto free; 2594 } 2595 if (operand1->flags & HIST_FIELD_FL_STRING) { 2596 hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(operand1_str)); 2597 ret = -EINVAL; 2598 goto free; 2599 } 2600 2601 /* RHS of string is another expression e.g. c in a+b+c */ 2602 operand_flags = 0; 2603 operand2 = parse_expr(hist_data, file, str, operand_flags, NULL, n_subexprs); 2604 if (IS_ERR(operand2)) { 2605 ret = PTR_ERR(operand2); 2606 operand2 = NULL; 2607 goto free; 2608 } 2609 if (operand2->flags & HIST_FIELD_FL_STRING) { 2610 hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(str)); 2611 ret = -EINVAL; 2612 goto free; 2613 } 2614 2615 switch (field_op) { 2616 case FIELD_OP_MINUS: 2617 op_fn = hist_field_minus; 2618 break; 2619 case FIELD_OP_PLUS: 2620 op_fn = hist_field_plus; 2621 break; 2622 case FIELD_OP_DIV: 2623 op_fn = hist_field_div; 2624 break; 2625 case FIELD_OP_MULT: 2626 op_fn = hist_field_mult; 2627 break; 2628 default: 2629 ret = -EINVAL; 2630 goto free; 2631 } 2632 2633 ret = check_expr_operands(file->tr, operand1, operand2, &var1, &var2); 2634 if (ret) 2635 goto free; 2636 2637 operand_flags = var1 ? var1->flags : operand1->flags; 2638 operand2_flags = var2 ? var2->flags : operand2->flags; 2639 2640 /* 2641 * If both operands are constant, the expression can be 2642 * collapsed to a single constant. 2643 */ 2644 combine_consts = operand_flags & operand2_flags & HIST_FIELD_FL_CONST; 2645 2646 flags |= combine_consts ? HIST_FIELD_FL_CONST : HIST_FIELD_FL_EXPR; 2647 2648 flags |= operand1->flags & 2649 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS); 2650 2651 expr = create_hist_field(hist_data, NULL, flags, var_name); 2652 if (!expr) { 2653 ret = -ENOMEM; 2654 goto free; 2655 } 2656 2657 operand1->read_once = true; 2658 operand2->read_once = true; 2659 2660 expr->operands[0] = operand1; 2661 expr->operands[1] = operand2; 2662 2663 if (field_op == FIELD_OP_DIV && 2664 operand2_flags & HIST_FIELD_FL_CONST) { 2665 u64 divisor = var2 ? var2->constant : operand2->constant; 2666 2667 if (!divisor) { 2668 hist_err(file->tr, HIST_ERR_DIVISION_BY_ZERO, errpos(str)); 2669 ret = -EDOM; 2670 goto free; 2671 } 2672 2673 /* 2674 * Copy the divisor here so we don't have to look it up 2675 * later if this is a var ref 2676 */ 2677 operand2->constant = divisor; 2678 op_fn = hist_field_get_div_fn(operand2); 2679 } 2680 2681 if (combine_consts) { 2682 if (var1) 2683 expr->operands[0] = var1; 2684 if (var2) 2685 expr->operands[1] = var2; 2686 2687 expr->constant = op_fn(expr, NULL, NULL, NULL, NULL); 2688 2689 expr->operands[0] = NULL; 2690 expr->operands[1] = NULL; 2691 2692 /* 2693 * var refs won't be destroyed immediately 2694 * See: destroy_hist_field() 2695 */ 2696 destroy_hist_field(operand2, 0); 2697 destroy_hist_field(operand1, 0); 2698 2699 expr->name = expr_str(expr, 0); 2700 } else { 2701 expr->fn = op_fn; 2702 2703 /* The operand sizes should be the same, so just pick one */ 2704 expr->size = operand1->size; 2705 2706 expr->operator = field_op; 2707 expr->type = kstrdup_const(operand1->type, GFP_KERNEL); 2708 if (!expr->type) { 2709 ret = -ENOMEM; 2710 goto free; 2711 } 2712 2713 expr->name = expr_str(expr, 0); 2714 } 2715 2716 return expr; 2717 free: 2718 destroy_hist_field(operand1, 0); 2719 destroy_hist_field(operand2, 0); 2720 destroy_hist_field(expr, 0); 2721 2722 return ERR_PTR(ret); 2723 } 2724 2725 static char *find_trigger_filter(struct hist_trigger_data *hist_data, 2726 struct trace_event_file *file) 2727 { 2728 struct event_trigger_data *test; 2729 2730 lockdep_assert_held(&event_mutex); 2731 2732 list_for_each_entry(test, &file->triggers, list) { 2733 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 2734 if (test->private_data == hist_data) 2735 return test->filter_str; 2736 } 2737 } 2738 2739 return NULL; 2740 } 2741 2742 static struct event_command trigger_hist_cmd; 2743 static int event_hist_trigger_func(struct event_command *cmd_ops, 2744 struct trace_event_file *file, 2745 char *glob, char *cmd, char *param); 2746 2747 static bool compatible_keys(struct hist_trigger_data *target_hist_data, 2748 struct hist_trigger_data *hist_data, 2749 unsigned int n_keys) 2750 { 2751 struct hist_field *target_hist_field, *hist_field; 2752 unsigned int n, i, j; 2753 2754 if (hist_data->n_fields - hist_data->n_vals != n_keys) 2755 return false; 2756 2757 i = hist_data->n_vals; 2758 j = target_hist_data->n_vals; 2759 2760 for (n = 0; n < n_keys; n++) { 2761 hist_field = hist_data->fields[i + n]; 2762 target_hist_field = target_hist_data->fields[j + n]; 2763 2764 if (strcmp(hist_field->type, target_hist_field->type) != 0) 2765 return false; 2766 if (hist_field->size != target_hist_field->size) 2767 return false; 2768 if (hist_field->is_signed != target_hist_field->is_signed) 2769 return false; 2770 } 2771 2772 return true; 2773 } 2774 2775 static struct hist_trigger_data * 2776 find_compatible_hist(struct hist_trigger_data *target_hist_data, 2777 struct trace_event_file *file) 2778 { 2779 struct hist_trigger_data *hist_data; 2780 struct event_trigger_data *test; 2781 unsigned int n_keys; 2782 2783 lockdep_assert_held(&event_mutex); 2784 2785 n_keys = target_hist_data->n_fields - target_hist_data->n_vals; 2786 2787 list_for_each_entry(test, &file->triggers, list) { 2788 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 2789 hist_data = test->private_data; 2790 2791 if (compatible_keys(target_hist_data, hist_data, n_keys)) 2792 return hist_data; 2793 } 2794 } 2795 2796 return NULL; 2797 } 2798 2799 static struct trace_event_file *event_file(struct trace_array *tr, 2800 char *system, char *event_name) 2801 { 2802 struct trace_event_file *file; 2803 2804 file = __find_event_file(tr, system, event_name); 2805 if (!file) 2806 return ERR_PTR(-EINVAL); 2807 2808 return file; 2809 } 2810 2811 static struct hist_field * 2812 find_synthetic_field_var(struct hist_trigger_data *target_hist_data, 2813 char *system, char *event_name, char *field_name) 2814 { 2815 struct hist_field *event_var; 2816 char *synthetic_name; 2817 2818 synthetic_name = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL); 2819 if (!synthetic_name) 2820 return ERR_PTR(-ENOMEM); 2821 2822 strcpy(synthetic_name, "synthetic_"); 2823 strcat(synthetic_name, field_name); 2824 2825 event_var = find_event_var(target_hist_data, system, event_name, synthetic_name); 2826 2827 kfree(synthetic_name); 2828 2829 return event_var; 2830 } 2831 2832 /** 2833 * create_field_var_hist - Automatically create a histogram and var for a field 2834 * @target_hist_data: The target hist trigger 2835 * @subsys_name: Optional subsystem name 2836 * @event_name: Optional event name 2837 * @field_name: The name of the field (and the resulting variable) 2838 * 2839 * Hist trigger actions fetch data from variables, not directly from 2840 * events. However, for convenience, users are allowed to directly 2841 * specify an event field in an action, which will be automatically 2842 * converted into a variable on their behalf. 2843 * 2844 * If a user specifies a field on an event that isn't the event the 2845 * histogram currently being defined (the target event histogram), the 2846 * only way that can be accomplished is if a new hist trigger is 2847 * created and the field variable defined on that. 2848 * 2849 * This function creates a new histogram compatible with the target 2850 * event (meaning a histogram with the same key as the target 2851 * histogram), and creates a variable for the specified field, but 2852 * with 'synthetic_' prepended to the variable name in order to avoid 2853 * collision with normal field variables. 2854 * 2855 * Return: The variable created for the field. 2856 */ 2857 static struct hist_field * 2858 create_field_var_hist(struct hist_trigger_data *target_hist_data, 2859 char *subsys_name, char *event_name, char *field_name) 2860 { 2861 struct trace_array *tr = target_hist_data->event_file->tr; 2862 struct hist_trigger_data *hist_data; 2863 unsigned int i, n, first = true; 2864 struct field_var_hist *var_hist; 2865 struct trace_event_file *file; 2866 struct hist_field *key_field; 2867 struct hist_field *event_var; 2868 char *saved_filter; 2869 char *cmd; 2870 int ret; 2871 2872 if (target_hist_data->n_field_var_hists >= SYNTH_FIELDS_MAX) { 2873 hist_err(tr, HIST_ERR_TOO_MANY_FIELD_VARS, errpos(field_name)); 2874 return ERR_PTR(-EINVAL); 2875 } 2876 2877 file = event_file(tr, subsys_name, event_name); 2878 2879 if (IS_ERR(file)) { 2880 hist_err(tr, HIST_ERR_EVENT_FILE_NOT_FOUND, errpos(field_name)); 2881 ret = PTR_ERR(file); 2882 return ERR_PTR(ret); 2883 } 2884 2885 /* 2886 * Look for a histogram compatible with target. We'll use the 2887 * found histogram specification to create a new matching 2888 * histogram with our variable on it. target_hist_data is not 2889 * yet a registered histogram so we can't use that. 2890 */ 2891 hist_data = find_compatible_hist(target_hist_data, file); 2892 if (!hist_data) { 2893 hist_err(tr, HIST_ERR_HIST_NOT_FOUND, errpos(field_name)); 2894 return ERR_PTR(-EINVAL); 2895 } 2896 2897 /* See if a synthetic field variable has already been created */ 2898 event_var = find_synthetic_field_var(target_hist_data, subsys_name, 2899 event_name, field_name); 2900 if (!IS_ERR_OR_NULL(event_var)) 2901 return event_var; 2902 2903 var_hist = kzalloc(sizeof(*var_hist), GFP_KERNEL); 2904 if (!var_hist) 2905 return ERR_PTR(-ENOMEM); 2906 2907 cmd = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL); 2908 if (!cmd) { 2909 kfree(var_hist); 2910 return ERR_PTR(-ENOMEM); 2911 } 2912 2913 /* Use the same keys as the compatible histogram */ 2914 strcat(cmd, "keys="); 2915 2916 for_each_hist_key_field(i, hist_data) { 2917 key_field = hist_data->fields[i]; 2918 if (!first) 2919 strcat(cmd, ","); 2920 strcat(cmd, key_field->field->name); 2921 first = false; 2922 } 2923 2924 /* Create the synthetic field variable specification */ 2925 strcat(cmd, ":synthetic_"); 2926 strcat(cmd, field_name); 2927 strcat(cmd, "="); 2928 strcat(cmd, field_name); 2929 2930 /* Use the same filter as the compatible histogram */ 2931 saved_filter = find_trigger_filter(hist_data, file); 2932 if (saved_filter) { 2933 strcat(cmd, " if "); 2934 strcat(cmd, saved_filter); 2935 } 2936 2937 var_hist->cmd = kstrdup(cmd, GFP_KERNEL); 2938 if (!var_hist->cmd) { 2939 kfree(cmd); 2940 kfree(var_hist); 2941 return ERR_PTR(-ENOMEM); 2942 } 2943 2944 /* Save the compatible histogram information */ 2945 var_hist->hist_data = hist_data; 2946 2947 /* Create the new histogram with our variable */ 2948 ret = event_hist_trigger_func(&trigger_hist_cmd, file, 2949 "", "hist", cmd); 2950 if (ret) { 2951 kfree(cmd); 2952 kfree(var_hist->cmd); 2953 kfree(var_hist); 2954 hist_err(tr, HIST_ERR_HIST_CREATE_FAIL, errpos(field_name)); 2955 return ERR_PTR(ret); 2956 } 2957 2958 kfree(cmd); 2959 2960 /* If we can't find the variable, something went wrong */ 2961 event_var = find_synthetic_field_var(target_hist_data, subsys_name, 2962 event_name, field_name); 2963 if (IS_ERR_OR_NULL(event_var)) { 2964 kfree(var_hist->cmd); 2965 kfree(var_hist); 2966 hist_err(tr, HIST_ERR_SYNTH_VAR_NOT_FOUND, errpos(field_name)); 2967 return ERR_PTR(-EINVAL); 2968 } 2969 2970 n = target_hist_data->n_field_var_hists; 2971 target_hist_data->field_var_hists[n] = var_hist; 2972 target_hist_data->n_field_var_hists++; 2973 2974 return event_var; 2975 } 2976 2977 static struct hist_field * 2978 find_target_event_var(struct hist_trigger_data *hist_data, 2979 char *subsys_name, char *event_name, char *var_name) 2980 { 2981 struct trace_event_file *file = hist_data->event_file; 2982 struct hist_field *hist_field = NULL; 2983 2984 if (subsys_name) { 2985 struct trace_event_call *call; 2986 2987 if (!event_name) 2988 return NULL; 2989 2990 call = file->event_call; 2991 2992 if (strcmp(subsys_name, call->class->system) != 0) 2993 return NULL; 2994 2995 if (strcmp(event_name, trace_event_name(call)) != 0) 2996 return NULL; 2997 } 2998 2999 hist_field = find_var_field(hist_data, var_name); 3000 3001 return hist_field; 3002 } 3003 3004 static inline void __update_field_vars(struct tracing_map_elt *elt, 3005 struct trace_buffer *buffer, 3006 struct ring_buffer_event *rbe, 3007 void *rec, 3008 struct field_var **field_vars, 3009 unsigned int n_field_vars, 3010 unsigned int field_var_str_start) 3011 { 3012 struct hist_elt_data *elt_data = elt->private_data; 3013 unsigned int i, j, var_idx; 3014 u64 var_val; 3015 3016 for (i = 0, j = field_var_str_start; i < n_field_vars; i++) { 3017 struct field_var *field_var = field_vars[i]; 3018 struct hist_field *var = field_var->var; 3019 struct hist_field *val = field_var->val; 3020 3021 var_val = val->fn(val, elt, buffer, rbe, rec); 3022 var_idx = var->var.idx; 3023 3024 if (val->flags & HIST_FIELD_FL_STRING) { 3025 char *str = elt_data->field_var_str[j++]; 3026 char *val_str = (char *)(uintptr_t)var_val; 3027 3028 strscpy(str, val_str, STR_VAR_LEN_MAX); 3029 var_val = (u64)(uintptr_t)str; 3030 } 3031 tracing_map_set_var(elt, var_idx, var_val); 3032 } 3033 } 3034 3035 static void update_field_vars(struct hist_trigger_data *hist_data, 3036 struct tracing_map_elt *elt, 3037 struct trace_buffer *buffer, 3038 struct ring_buffer_event *rbe, 3039 void *rec) 3040 { 3041 __update_field_vars(elt, buffer, rbe, rec, hist_data->field_vars, 3042 hist_data->n_field_vars, 0); 3043 } 3044 3045 static void save_track_data_vars(struct hist_trigger_data *hist_data, 3046 struct tracing_map_elt *elt, 3047 struct trace_buffer *buffer, void *rec, 3048 struct ring_buffer_event *rbe, void *key, 3049 struct action_data *data, u64 *var_ref_vals) 3050 { 3051 __update_field_vars(elt, buffer, rbe, rec, hist_data->save_vars, 3052 hist_data->n_save_vars, hist_data->n_field_var_str); 3053 } 3054 3055 static struct hist_field *create_var(struct hist_trigger_data *hist_data, 3056 struct trace_event_file *file, 3057 char *name, int size, const char *type) 3058 { 3059 struct hist_field *var; 3060 int idx; 3061 3062 if (find_var(hist_data, file, name) && !hist_data->remove) { 3063 var = ERR_PTR(-EINVAL); 3064 goto out; 3065 } 3066 3067 var = kzalloc(sizeof(struct hist_field), GFP_KERNEL); 3068 if (!var) { 3069 var = ERR_PTR(-ENOMEM); 3070 goto out; 3071 } 3072 3073 idx = tracing_map_add_var(hist_data->map); 3074 if (idx < 0) { 3075 kfree(var); 3076 var = ERR_PTR(-EINVAL); 3077 goto out; 3078 } 3079 3080 var->ref = 1; 3081 var->flags = HIST_FIELD_FL_VAR; 3082 var->var.idx = idx; 3083 var->var.hist_data = var->hist_data = hist_data; 3084 var->size = size; 3085 var->var.name = kstrdup(name, GFP_KERNEL); 3086 var->type = kstrdup_const(type, GFP_KERNEL); 3087 if (!var->var.name || !var->type) { 3088 kfree_const(var->type); 3089 kfree(var->var.name); 3090 kfree(var); 3091 var = ERR_PTR(-ENOMEM); 3092 } 3093 out: 3094 return var; 3095 } 3096 3097 static struct field_var *create_field_var(struct hist_trigger_data *hist_data, 3098 struct trace_event_file *file, 3099 char *field_name) 3100 { 3101 struct hist_field *val = NULL, *var = NULL; 3102 unsigned long flags = HIST_FIELD_FL_VAR; 3103 struct trace_array *tr = file->tr; 3104 struct field_var *field_var; 3105 int ret = 0; 3106 3107 if (hist_data->n_field_vars >= SYNTH_FIELDS_MAX) { 3108 hist_err(tr, HIST_ERR_TOO_MANY_FIELD_VARS, errpos(field_name)); 3109 ret = -EINVAL; 3110 goto err; 3111 } 3112 3113 val = parse_atom(hist_data, file, field_name, &flags, NULL); 3114 if (IS_ERR(val)) { 3115 hist_err(tr, HIST_ERR_FIELD_VAR_PARSE_FAIL, errpos(field_name)); 3116 ret = PTR_ERR(val); 3117 goto err; 3118 } 3119 3120 var = create_var(hist_data, file, field_name, val->size, val->type); 3121 if (IS_ERR(var)) { 3122 hist_err(tr, HIST_ERR_VAR_CREATE_FIND_FAIL, errpos(field_name)); 3123 kfree(val); 3124 ret = PTR_ERR(var); 3125 goto err; 3126 } 3127 3128 field_var = kzalloc(sizeof(struct field_var), GFP_KERNEL); 3129 if (!field_var) { 3130 kfree(val); 3131 kfree(var); 3132 ret = -ENOMEM; 3133 goto err; 3134 } 3135 3136 field_var->var = var; 3137 field_var->val = val; 3138 out: 3139 return field_var; 3140 err: 3141 field_var = ERR_PTR(ret); 3142 goto out; 3143 } 3144 3145 /** 3146 * create_target_field_var - Automatically create a variable for a field 3147 * @target_hist_data: The target hist trigger 3148 * @subsys_name: Optional subsystem name 3149 * @event_name: Optional event name 3150 * @var_name: The name of the field (and the resulting variable) 3151 * 3152 * Hist trigger actions fetch data from variables, not directly from 3153 * events. However, for convenience, users are allowed to directly 3154 * specify an event field in an action, which will be automatically 3155 * converted into a variable on their behalf. 3156 3157 * This function creates a field variable with the name var_name on 3158 * the hist trigger currently being defined on the target event. If 3159 * subsys_name and event_name are specified, this function simply 3160 * verifies that they do in fact match the target event subsystem and 3161 * event name. 3162 * 3163 * Return: The variable created for the field. 3164 */ 3165 static struct field_var * 3166 create_target_field_var(struct hist_trigger_data *target_hist_data, 3167 char *subsys_name, char *event_name, char *var_name) 3168 { 3169 struct trace_event_file *file = target_hist_data->event_file; 3170 3171 if (subsys_name) { 3172 struct trace_event_call *call; 3173 3174 if (!event_name) 3175 return NULL; 3176 3177 call = file->event_call; 3178 3179 if (strcmp(subsys_name, call->class->system) != 0) 3180 return NULL; 3181 3182 if (strcmp(event_name, trace_event_name(call)) != 0) 3183 return NULL; 3184 } 3185 3186 return create_field_var(target_hist_data, file, var_name); 3187 } 3188 3189 static bool check_track_val_max(u64 track_val, u64 var_val) 3190 { 3191 if (var_val <= track_val) 3192 return false; 3193 3194 return true; 3195 } 3196 3197 static bool check_track_val_changed(u64 track_val, u64 var_val) 3198 { 3199 if (var_val == track_val) 3200 return false; 3201 3202 return true; 3203 } 3204 3205 static u64 get_track_val(struct hist_trigger_data *hist_data, 3206 struct tracing_map_elt *elt, 3207 struct action_data *data) 3208 { 3209 unsigned int track_var_idx = data->track_data.track_var->var.idx; 3210 u64 track_val; 3211 3212 track_val = tracing_map_read_var(elt, track_var_idx); 3213 3214 return track_val; 3215 } 3216 3217 static void save_track_val(struct hist_trigger_data *hist_data, 3218 struct tracing_map_elt *elt, 3219 struct action_data *data, u64 var_val) 3220 { 3221 unsigned int track_var_idx = data->track_data.track_var->var.idx; 3222 3223 tracing_map_set_var(elt, track_var_idx, var_val); 3224 } 3225 3226 static void save_track_data(struct hist_trigger_data *hist_data, 3227 struct tracing_map_elt *elt, 3228 struct trace_buffer *buffer, void *rec, 3229 struct ring_buffer_event *rbe, void *key, 3230 struct action_data *data, u64 *var_ref_vals) 3231 { 3232 if (data->track_data.save_data) 3233 data->track_data.save_data(hist_data, elt, buffer, rec, rbe, 3234 key, data, var_ref_vals); 3235 } 3236 3237 static bool check_track_val(struct tracing_map_elt *elt, 3238 struct action_data *data, 3239 u64 var_val) 3240 { 3241 struct hist_trigger_data *hist_data; 3242 u64 track_val; 3243 3244 hist_data = data->track_data.track_var->hist_data; 3245 track_val = get_track_val(hist_data, elt, data); 3246 3247 return data->track_data.check_val(track_val, var_val); 3248 } 3249 3250 #ifdef CONFIG_TRACER_SNAPSHOT 3251 static bool cond_snapshot_update(struct trace_array *tr, void *cond_data) 3252 { 3253 /* called with tr->max_lock held */ 3254 struct track_data *track_data = tr->cond_snapshot->cond_data; 3255 struct hist_elt_data *elt_data, *track_elt_data; 3256 struct snapshot_context *context = cond_data; 3257 struct action_data *action; 3258 u64 track_val; 3259 3260 if (!track_data) 3261 return false; 3262 3263 action = track_data->action_data; 3264 3265 track_val = get_track_val(track_data->hist_data, context->elt, 3266 track_data->action_data); 3267 3268 if (!action->track_data.check_val(track_data->track_val, track_val)) 3269 return false; 3270 3271 track_data->track_val = track_val; 3272 memcpy(track_data->key, context->key, track_data->key_len); 3273 3274 elt_data = context->elt->private_data; 3275 track_elt_data = track_data->elt.private_data; 3276 if (elt_data->comm) 3277 strncpy(track_elt_data->comm, elt_data->comm, TASK_COMM_LEN); 3278 3279 track_data->updated = true; 3280 3281 return true; 3282 } 3283 3284 static void save_track_data_snapshot(struct hist_trigger_data *hist_data, 3285 struct tracing_map_elt *elt, 3286 struct trace_buffer *buffer, void *rec, 3287 struct ring_buffer_event *rbe, void *key, 3288 struct action_data *data, 3289 u64 *var_ref_vals) 3290 { 3291 struct trace_event_file *file = hist_data->event_file; 3292 struct snapshot_context context; 3293 3294 context.elt = elt; 3295 context.key = key; 3296 3297 tracing_snapshot_cond(file->tr, &context); 3298 } 3299 3300 static void hist_trigger_print_key(struct seq_file *m, 3301 struct hist_trigger_data *hist_data, 3302 void *key, 3303 struct tracing_map_elt *elt); 3304 3305 static struct action_data *snapshot_action(struct hist_trigger_data *hist_data) 3306 { 3307 unsigned int i; 3308 3309 if (!hist_data->n_actions) 3310 return NULL; 3311 3312 for (i = 0; i < hist_data->n_actions; i++) { 3313 struct action_data *data = hist_data->actions[i]; 3314 3315 if (data->action == ACTION_SNAPSHOT) 3316 return data; 3317 } 3318 3319 return NULL; 3320 } 3321 3322 static void track_data_snapshot_print(struct seq_file *m, 3323 struct hist_trigger_data *hist_data) 3324 { 3325 struct trace_event_file *file = hist_data->event_file; 3326 struct track_data *track_data; 3327 struct action_data *action; 3328 3329 track_data = tracing_cond_snapshot_data(file->tr); 3330 if (!track_data) 3331 return; 3332 3333 if (!track_data->updated) 3334 return; 3335 3336 action = snapshot_action(hist_data); 3337 if (!action) 3338 return; 3339 3340 seq_puts(m, "\nSnapshot taken (see tracing/snapshot). Details:\n"); 3341 seq_printf(m, "\ttriggering value { %s(%s) }: %10llu", 3342 action->handler == HANDLER_ONMAX ? "onmax" : "onchange", 3343 action->track_data.var_str, track_data->track_val); 3344 3345 seq_puts(m, "\ttriggered by event with key: "); 3346 hist_trigger_print_key(m, hist_data, track_data->key, &track_data->elt); 3347 seq_putc(m, '\n'); 3348 } 3349 #else 3350 static bool cond_snapshot_update(struct trace_array *tr, void *cond_data) 3351 { 3352 return false; 3353 } 3354 static void save_track_data_snapshot(struct hist_trigger_data *hist_data, 3355 struct tracing_map_elt *elt, 3356 struct trace_buffer *buffer, void *rec, 3357 struct ring_buffer_event *rbe, void *key, 3358 struct action_data *data, 3359 u64 *var_ref_vals) {} 3360 static void track_data_snapshot_print(struct seq_file *m, 3361 struct hist_trigger_data *hist_data) {} 3362 #endif /* CONFIG_TRACER_SNAPSHOT */ 3363 3364 static void track_data_print(struct seq_file *m, 3365 struct hist_trigger_data *hist_data, 3366 struct tracing_map_elt *elt, 3367 struct action_data *data) 3368 { 3369 u64 track_val = get_track_val(hist_data, elt, data); 3370 unsigned int i, save_var_idx; 3371 3372 if (data->handler == HANDLER_ONMAX) 3373 seq_printf(m, "\n\tmax: %10llu", track_val); 3374 else if (data->handler == HANDLER_ONCHANGE) 3375 seq_printf(m, "\n\tchanged: %10llu", track_val); 3376 3377 if (data->action == ACTION_SNAPSHOT) 3378 return; 3379 3380 for (i = 0; i < hist_data->n_save_vars; i++) { 3381 struct hist_field *save_val = hist_data->save_vars[i]->val; 3382 struct hist_field *save_var = hist_data->save_vars[i]->var; 3383 u64 val; 3384 3385 save_var_idx = save_var->var.idx; 3386 3387 val = tracing_map_read_var(elt, save_var_idx); 3388 3389 if (save_val->flags & HIST_FIELD_FL_STRING) { 3390 seq_printf(m, " %s: %-32s", save_var->var.name, 3391 (char *)(uintptr_t)(val)); 3392 } else 3393 seq_printf(m, " %s: %10llu", save_var->var.name, val); 3394 } 3395 } 3396 3397 static void ontrack_action(struct hist_trigger_data *hist_data, 3398 struct tracing_map_elt *elt, 3399 struct trace_buffer *buffer, void *rec, 3400 struct ring_buffer_event *rbe, void *key, 3401 struct action_data *data, u64 *var_ref_vals) 3402 { 3403 u64 var_val = var_ref_vals[data->track_data.var_ref->var_ref_idx]; 3404 3405 if (check_track_val(elt, data, var_val)) { 3406 save_track_val(hist_data, elt, data, var_val); 3407 save_track_data(hist_data, elt, buffer, rec, rbe, 3408 key, data, var_ref_vals); 3409 } 3410 } 3411 3412 static void action_data_destroy(struct action_data *data) 3413 { 3414 unsigned int i; 3415 3416 lockdep_assert_held(&event_mutex); 3417 3418 kfree(data->action_name); 3419 3420 for (i = 0; i < data->n_params; i++) 3421 kfree(data->params[i]); 3422 3423 if (data->synth_event) 3424 data->synth_event->ref--; 3425 3426 kfree(data->synth_event_name); 3427 3428 kfree(data); 3429 } 3430 3431 static void track_data_destroy(struct hist_trigger_data *hist_data, 3432 struct action_data *data) 3433 { 3434 struct trace_event_file *file = hist_data->event_file; 3435 3436 destroy_hist_field(data->track_data.track_var, 0); 3437 3438 if (data->action == ACTION_SNAPSHOT) { 3439 struct track_data *track_data; 3440 3441 track_data = tracing_cond_snapshot_data(file->tr); 3442 if (track_data && track_data->hist_data == hist_data) { 3443 tracing_snapshot_cond_disable(file->tr); 3444 track_data_free(track_data); 3445 } 3446 } 3447 3448 kfree(data->track_data.var_str); 3449 3450 action_data_destroy(data); 3451 } 3452 3453 static int action_create(struct hist_trigger_data *hist_data, 3454 struct action_data *data); 3455 3456 static int track_data_create(struct hist_trigger_data *hist_data, 3457 struct action_data *data) 3458 { 3459 struct hist_field *var_field, *ref_field, *track_var = NULL; 3460 struct trace_event_file *file = hist_data->event_file; 3461 struct trace_array *tr = file->tr; 3462 char *track_data_var_str; 3463 int ret = 0; 3464 3465 track_data_var_str = data->track_data.var_str; 3466 if (track_data_var_str[0] != '$') { 3467 hist_err(tr, HIST_ERR_ONX_NOT_VAR, errpos(track_data_var_str)); 3468 return -EINVAL; 3469 } 3470 track_data_var_str++; 3471 3472 var_field = find_target_event_var(hist_data, NULL, NULL, track_data_var_str); 3473 if (!var_field) { 3474 hist_err(tr, HIST_ERR_ONX_VAR_NOT_FOUND, errpos(track_data_var_str)); 3475 return -EINVAL; 3476 } 3477 3478 ref_field = create_var_ref(hist_data, var_field, NULL, NULL); 3479 if (!ref_field) 3480 return -ENOMEM; 3481 3482 data->track_data.var_ref = ref_field; 3483 3484 if (data->handler == HANDLER_ONMAX) 3485 track_var = create_var(hist_data, file, "__max", sizeof(u64), "u64"); 3486 if (IS_ERR(track_var)) { 3487 hist_err(tr, HIST_ERR_ONX_VAR_CREATE_FAIL, 0); 3488 ret = PTR_ERR(track_var); 3489 goto out; 3490 } 3491 3492 if (data->handler == HANDLER_ONCHANGE) 3493 track_var = create_var(hist_data, file, "__change", sizeof(u64), "u64"); 3494 if (IS_ERR(track_var)) { 3495 hist_err(tr, HIST_ERR_ONX_VAR_CREATE_FAIL, 0); 3496 ret = PTR_ERR(track_var); 3497 goto out; 3498 } 3499 data->track_data.track_var = track_var; 3500 3501 ret = action_create(hist_data, data); 3502 out: 3503 return ret; 3504 } 3505 3506 static int parse_action_params(struct trace_array *tr, char *params, 3507 struct action_data *data) 3508 { 3509 char *param, *saved_param; 3510 bool first_param = true; 3511 int ret = 0; 3512 3513 while (params) { 3514 if (data->n_params >= SYNTH_FIELDS_MAX) { 3515 hist_err(tr, HIST_ERR_TOO_MANY_PARAMS, 0); 3516 goto out; 3517 } 3518 3519 param = strsep(¶ms, ","); 3520 if (!param) { 3521 hist_err(tr, HIST_ERR_PARAM_NOT_FOUND, 0); 3522 ret = -EINVAL; 3523 goto out; 3524 } 3525 3526 param = strstrip(param); 3527 if (strlen(param) < 2) { 3528 hist_err(tr, HIST_ERR_INVALID_PARAM, errpos(param)); 3529 ret = -EINVAL; 3530 goto out; 3531 } 3532 3533 saved_param = kstrdup(param, GFP_KERNEL); 3534 if (!saved_param) { 3535 ret = -ENOMEM; 3536 goto out; 3537 } 3538 3539 if (first_param && data->use_trace_keyword) { 3540 data->synth_event_name = saved_param; 3541 first_param = false; 3542 continue; 3543 } 3544 first_param = false; 3545 3546 data->params[data->n_params++] = saved_param; 3547 } 3548 out: 3549 return ret; 3550 } 3551 3552 static int action_parse(struct trace_array *tr, char *str, struct action_data *data, 3553 enum handler_id handler) 3554 { 3555 char *action_name; 3556 int ret = 0; 3557 3558 strsep(&str, "."); 3559 if (!str) { 3560 hist_err(tr, HIST_ERR_ACTION_NOT_FOUND, 0); 3561 ret = -EINVAL; 3562 goto out; 3563 } 3564 3565 action_name = strsep(&str, "("); 3566 if (!action_name || !str) { 3567 hist_err(tr, HIST_ERR_ACTION_NOT_FOUND, 0); 3568 ret = -EINVAL; 3569 goto out; 3570 } 3571 3572 if (str_has_prefix(action_name, "save")) { 3573 char *params = strsep(&str, ")"); 3574 3575 if (!params) { 3576 hist_err(tr, HIST_ERR_NO_SAVE_PARAMS, 0); 3577 ret = -EINVAL; 3578 goto out; 3579 } 3580 3581 ret = parse_action_params(tr, params, data); 3582 if (ret) 3583 goto out; 3584 3585 if (handler == HANDLER_ONMAX) 3586 data->track_data.check_val = check_track_val_max; 3587 else if (handler == HANDLER_ONCHANGE) 3588 data->track_data.check_val = check_track_val_changed; 3589 else { 3590 hist_err(tr, HIST_ERR_ACTION_MISMATCH, errpos(action_name)); 3591 ret = -EINVAL; 3592 goto out; 3593 } 3594 3595 data->track_data.save_data = save_track_data_vars; 3596 data->fn = ontrack_action; 3597 data->action = ACTION_SAVE; 3598 } else if (str_has_prefix(action_name, "snapshot")) { 3599 char *params = strsep(&str, ")"); 3600 3601 if (!str) { 3602 hist_err(tr, HIST_ERR_NO_CLOSING_PAREN, errpos(params)); 3603 ret = -EINVAL; 3604 goto out; 3605 } 3606 3607 if (handler == HANDLER_ONMAX) 3608 data->track_data.check_val = check_track_val_max; 3609 else if (handler == HANDLER_ONCHANGE) 3610 data->track_data.check_val = check_track_val_changed; 3611 else { 3612 hist_err(tr, HIST_ERR_ACTION_MISMATCH, errpos(action_name)); 3613 ret = -EINVAL; 3614 goto out; 3615 } 3616 3617 data->track_data.save_data = save_track_data_snapshot; 3618 data->fn = ontrack_action; 3619 data->action = ACTION_SNAPSHOT; 3620 } else { 3621 char *params = strsep(&str, ")"); 3622 3623 if (str_has_prefix(action_name, "trace")) 3624 data->use_trace_keyword = true; 3625 3626 if (params) { 3627 ret = parse_action_params(tr, params, data); 3628 if (ret) 3629 goto out; 3630 } 3631 3632 if (handler == HANDLER_ONMAX) 3633 data->track_data.check_val = check_track_val_max; 3634 else if (handler == HANDLER_ONCHANGE) 3635 data->track_data.check_val = check_track_val_changed; 3636 3637 if (handler != HANDLER_ONMATCH) { 3638 data->track_data.save_data = action_trace; 3639 data->fn = ontrack_action; 3640 } else 3641 data->fn = action_trace; 3642 3643 data->action = ACTION_TRACE; 3644 } 3645 3646 data->action_name = kstrdup(action_name, GFP_KERNEL); 3647 if (!data->action_name) { 3648 ret = -ENOMEM; 3649 goto out; 3650 } 3651 3652 data->handler = handler; 3653 out: 3654 return ret; 3655 } 3656 3657 static struct action_data *track_data_parse(struct hist_trigger_data *hist_data, 3658 char *str, enum handler_id handler) 3659 { 3660 struct action_data *data; 3661 int ret = -EINVAL; 3662 char *var_str; 3663 3664 data = kzalloc(sizeof(*data), GFP_KERNEL); 3665 if (!data) 3666 return ERR_PTR(-ENOMEM); 3667 3668 var_str = strsep(&str, ")"); 3669 if (!var_str || !str) { 3670 ret = -EINVAL; 3671 goto free; 3672 } 3673 3674 data->track_data.var_str = kstrdup(var_str, GFP_KERNEL); 3675 if (!data->track_data.var_str) { 3676 ret = -ENOMEM; 3677 goto free; 3678 } 3679 3680 ret = action_parse(hist_data->event_file->tr, str, data, handler); 3681 if (ret) 3682 goto free; 3683 out: 3684 return data; 3685 free: 3686 track_data_destroy(hist_data, data); 3687 data = ERR_PTR(ret); 3688 goto out; 3689 } 3690 3691 static void onmatch_destroy(struct action_data *data) 3692 { 3693 kfree(data->match_data.event); 3694 kfree(data->match_data.event_system); 3695 3696 action_data_destroy(data); 3697 } 3698 3699 static void destroy_field_var(struct field_var *field_var) 3700 { 3701 if (!field_var) 3702 return; 3703 3704 destroy_hist_field(field_var->var, 0); 3705 destroy_hist_field(field_var->val, 0); 3706 3707 kfree(field_var); 3708 } 3709 3710 static void destroy_field_vars(struct hist_trigger_data *hist_data) 3711 { 3712 unsigned int i; 3713 3714 for (i = 0; i < hist_data->n_field_vars; i++) 3715 destroy_field_var(hist_data->field_vars[i]); 3716 3717 for (i = 0; i < hist_data->n_save_vars; i++) 3718 destroy_field_var(hist_data->save_vars[i]); 3719 } 3720 3721 static void save_field_var(struct hist_trigger_data *hist_data, 3722 struct field_var *field_var) 3723 { 3724 hist_data->field_vars[hist_data->n_field_vars++] = field_var; 3725 3726 if (field_var->val->flags & HIST_FIELD_FL_STRING) 3727 hist_data->n_field_var_str++; 3728 } 3729 3730 3731 static int check_synth_field(struct synth_event *event, 3732 struct hist_field *hist_field, 3733 unsigned int field_pos) 3734 { 3735 struct synth_field *field; 3736 3737 if (field_pos >= event->n_fields) 3738 return -EINVAL; 3739 3740 field = event->fields[field_pos]; 3741 3742 /* 3743 * A dynamic string synth field can accept static or 3744 * dynamic. A static string synth field can only accept a 3745 * same-sized static string, which is checked for later. 3746 */ 3747 if (strstr(hist_field->type, "char[") && field->is_string 3748 && field->is_dynamic) 3749 return 0; 3750 3751 if (strcmp(field->type, hist_field->type) != 0) { 3752 if (field->size != hist_field->size || 3753 field->is_signed != hist_field->is_signed) 3754 return -EINVAL; 3755 } 3756 3757 return 0; 3758 } 3759 3760 static struct hist_field * 3761 trace_action_find_var(struct hist_trigger_data *hist_data, 3762 struct action_data *data, 3763 char *system, char *event, char *var) 3764 { 3765 struct trace_array *tr = hist_data->event_file->tr; 3766 struct hist_field *hist_field; 3767 3768 var++; /* skip '$' */ 3769 3770 hist_field = find_target_event_var(hist_data, system, event, var); 3771 if (!hist_field) { 3772 if (!system && data->handler == HANDLER_ONMATCH) { 3773 system = data->match_data.event_system; 3774 event = data->match_data.event; 3775 } 3776 3777 hist_field = find_event_var(hist_data, system, event, var); 3778 } 3779 3780 if (!hist_field) 3781 hist_err(tr, HIST_ERR_PARAM_NOT_FOUND, errpos(var)); 3782 3783 return hist_field; 3784 } 3785 3786 static struct hist_field * 3787 trace_action_create_field_var(struct hist_trigger_data *hist_data, 3788 struct action_data *data, char *system, 3789 char *event, char *var) 3790 { 3791 struct hist_field *hist_field = NULL; 3792 struct field_var *field_var; 3793 3794 /* 3795 * First try to create a field var on the target event (the 3796 * currently being defined). This will create a variable for 3797 * unqualified fields on the target event, or if qualified, 3798 * target fields that have qualified names matching the target. 3799 */ 3800 field_var = create_target_field_var(hist_data, system, event, var); 3801 3802 if (field_var && !IS_ERR(field_var)) { 3803 save_field_var(hist_data, field_var); 3804 hist_field = field_var->var; 3805 } else { 3806 field_var = NULL; 3807 /* 3808 * If no explicit system.event is specified, default to 3809 * looking for fields on the onmatch(system.event.xxx) 3810 * event. 3811 */ 3812 if (!system && data->handler == HANDLER_ONMATCH) { 3813 system = data->match_data.event_system; 3814 event = data->match_data.event; 3815 } 3816 3817 if (!event) 3818 goto free; 3819 /* 3820 * At this point, we're looking at a field on another 3821 * event. Because we can't modify a hist trigger on 3822 * another event to add a variable for a field, we need 3823 * to create a new trigger on that event and create the 3824 * variable at the same time. 3825 */ 3826 hist_field = create_field_var_hist(hist_data, system, event, var); 3827 if (IS_ERR(hist_field)) 3828 goto free; 3829 } 3830 out: 3831 return hist_field; 3832 free: 3833 destroy_field_var(field_var); 3834 hist_field = NULL; 3835 goto out; 3836 } 3837 3838 static int trace_action_create(struct hist_trigger_data *hist_data, 3839 struct action_data *data) 3840 { 3841 struct trace_array *tr = hist_data->event_file->tr; 3842 char *event_name, *param, *system = NULL; 3843 struct hist_field *hist_field, *var_ref; 3844 unsigned int i; 3845 unsigned int field_pos = 0; 3846 struct synth_event *event; 3847 char *synth_event_name; 3848 int var_ref_idx, ret = 0; 3849 3850 lockdep_assert_held(&event_mutex); 3851 3852 if (data->use_trace_keyword) 3853 synth_event_name = data->synth_event_name; 3854 else 3855 synth_event_name = data->action_name; 3856 3857 event = find_synth_event(synth_event_name); 3858 if (!event) { 3859 hist_err(tr, HIST_ERR_SYNTH_EVENT_NOT_FOUND, errpos(synth_event_name)); 3860 return -EINVAL; 3861 } 3862 3863 event->ref++; 3864 3865 for (i = 0; i < data->n_params; i++) { 3866 char *p; 3867 3868 p = param = kstrdup(data->params[i], GFP_KERNEL); 3869 if (!param) { 3870 ret = -ENOMEM; 3871 goto err; 3872 } 3873 3874 system = strsep(¶m, "."); 3875 if (!param) { 3876 param = (char *)system; 3877 system = event_name = NULL; 3878 } else { 3879 event_name = strsep(¶m, "."); 3880 if (!param) { 3881 kfree(p); 3882 ret = -EINVAL; 3883 goto err; 3884 } 3885 } 3886 3887 if (param[0] == '$') 3888 hist_field = trace_action_find_var(hist_data, data, 3889 system, event_name, 3890 param); 3891 else 3892 hist_field = trace_action_create_field_var(hist_data, 3893 data, 3894 system, 3895 event_name, 3896 param); 3897 3898 if (!hist_field) { 3899 kfree(p); 3900 ret = -EINVAL; 3901 goto err; 3902 } 3903 3904 if (check_synth_field(event, hist_field, field_pos) == 0) { 3905 var_ref = create_var_ref(hist_data, hist_field, 3906 system, event_name); 3907 if (!var_ref) { 3908 kfree(p); 3909 ret = -ENOMEM; 3910 goto err; 3911 } 3912 3913 var_ref_idx = find_var_ref_idx(hist_data, var_ref); 3914 if (WARN_ON(var_ref_idx < 0)) { 3915 ret = var_ref_idx; 3916 goto err; 3917 } 3918 3919 data->var_ref_idx[i] = var_ref_idx; 3920 3921 field_pos++; 3922 kfree(p); 3923 continue; 3924 } 3925 3926 hist_err(tr, HIST_ERR_SYNTH_TYPE_MISMATCH, errpos(param)); 3927 kfree(p); 3928 ret = -EINVAL; 3929 goto err; 3930 } 3931 3932 if (field_pos != event->n_fields) { 3933 hist_err(tr, HIST_ERR_SYNTH_COUNT_MISMATCH, errpos(event->name)); 3934 ret = -EINVAL; 3935 goto err; 3936 } 3937 3938 data->synth_event = event; 3939 out: 3940 return ret; 3941 err: 3942 event->ref--; 3943 3944 goto out; 3945 } 3946 3947 static int action_create(struct hist_trigger_data *hist_data, 3948 struct action_data *data) 3949 { 3950 struct trace_event_file *file = hist_data->event_file; 3951 struct trace_array *tr = file->tr; 3952 struct track_data *track_data; 3953 struct field_var *field_var; 3954 unsigned int i; 3955 char *param; 3956 int ret = 0; 3957 3958 if (data->action == ACTION_TRACE) 3959 return trace_action_create(hist_data, data); 3960 3961 if (data->action == ACTION_SNAPSHOT) { 3962 track_data = track_data_alloc(hist_data->key_size, data, hist_data); 3963 if (IS_ERR(track_data)) { 3964 ret = PTR_ERR(track_data); 3965 goto out; 3966 } 3967 3968 ret = tracing_snapshot_cond_enable(file->tr, track_data, 3969 cond_snapshot_update); 3970 if (ret) 3971 track_data_free(track_data); 3972 3973 goto out; 3974 } 3975 3976 if (data->action == ACTION_SAVE) { 3977 if (hist_data->n_save_vars) { 3978 ret = -EEXIST; 3979 hist_err(tr, HIST_ERR_TOO_MANY_SAVE_ACTIONS, 0); 3980 goto out; 3981 } 3982 3983 for (i = 0; i < data->n_params; i++) { 3984 param = kstrdup(data->params[i], GFP_KERNEL); 3985 if (!param) { 3986 ret = -ENOMEM; 3987 goto out; 3988 } 3989 3990 field_var = create_target_field_var(hist_data, NULL, NULL, param); 3991 if (IS_ERR(field_var)) { 3992 hist_err(tr, HIST_ERR_FIELD_VAR_CREATE_FAIL, 3993 errpos(param)); 3994 ret = PTR_ERR(field_var); 3995 kfree(param); 3996 goto out; 3997 } 3998 3999 hist_data->save_vars[hist_data->n_save_vars++] = field_var; 4000 if (field_var->val->flags & HIST_FIELD_FL_STRING) 4001 hist_data->n_save_var_str++; 4002 kfree(param); 4003 } 4004 } 4005 out: 4006 return ret; 4007 } 4008 4009 static int onmatch_create(struct hist_trigger_data *hist_data, 4010 struct action_data *data) 4011 { 4012 return action_create(hist_data, data); 4013 } 4014 4015 static struct action_data *onmatch_parse(struct trace_array *tr, char *str) 4016 { 4017 char *match_event, *match_event_system; 4018 struct action_data *data; 4019 int ret = -EINVAL; 4020 4021 data = kzalloc(sizeof(*data), GFP_KERNEL); 4022 if (!data) 4023 return ERR_PTR(-ENOMEM); 4024 4025 match_event = strsep(&str, ")"); 4026 if (!match_event || !str) { 4027 hist_err(tr, HIST_ERR_NO_CLOSING_PAREN, errpos(match_event)); 4028 goto free; 4029 } 4030 4031 match_event_system = strsep(&match_event, "."); 4032 if (!match_event) { 4033 hist_err(tr, HIST_ERR_SUBSYS_NOT_FOUND, errpos(match_event_system)); 4034 goto free; 4035 } 4036 4037 if (IS_ERR(event_file(tr, match_event_system, match_event))) { 4038 hist_err(tr, HIST_ERR_INVALID_SUBSYS_EVENT, errpos(match_event)); 4039 goto free; 4040 } 4041 4042 data->match_data.event = kstrdup(match_event, GFP_KERNEL); 4043 if (!data->match_data.event) { 4044 ret = -ENOMEM; 4045 goto free; 4046 } 4047 4048 data->match_data.event_system = kstrdup(match_event_system, GFP_KERNEL); 4049 if (!data->match_data.event_system) { 4050 ret = -ENOMEM; 4051 goto free; 4052 } 4053 4054 ret = action_parse(tr, str, data, HANDLER_ONMATCH); 4055 if (ret) 4056 goto free; 4057 out: 4058 return data; 4059 free: 4060 onmatch_destroy(data); 4061 data = ERR_PTR(ret); 4062 goto out; 4063 } 4064 4065 static int create_hitcount_val(struct hist_trigger_data *hist_data) 4066 { 4067 hist_data->fields[HITCOUNT_IDX] = 4068 create_hist_field(hist_data, NULL, HIST_FIELD_FL_HITCOUNT, NULL); 4069 if (!hist_data->fields[HITCOUNT_IDX]) 4070 return -ENOMEM; 4071 4072 hist_data->n_vals++; 4073 hist_data->n_fields++; 4074 4075 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX)) 4076 return -EINVAL; 4077 4078 return 0; 4079 } 4080 4081 static int __create_val_field(struct hist_trigger_data *hist_data, 4082 unsigned int val_idx, 4083 struct trace_event_file *file, 4084 char *var_name, char *field_str, 4085 unsigned long flags) 4086 { 4087 struct hist_field *hist_field; 4088 int ret = 0, n_subexprs = 0; 4089 4090 hist_field = parse_expr(hist_data, file, field_str, flags, var_name, &n_subexprs); 4091 if (IS_ERR(hist_field)) { 4092 ret = PTR_ERR(hist_field); 4093 goto out; 4094 } 4095 4096 hist_data->fields[val_idx] = hist_field; 4097 4098 ++hist_data->n_vals; 4099 ++hist_data->n_fields; 4100 4101 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX)) 4102 ret = -EINVAL; 4103 out: 4104 return ret; 4105 } 4106 4107 static int create_val_field(struct hist_trigger_data *hist_data, 4108 unsigned int val_idx, 4109 struct trace_event_file *file, 4110 char *field_str) 4111 { 4112 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX)) 4113 return -EINVAL; 4114 4115 return __create_val_field(hist_data, val_idx, file, NULL, field_str, 0); 4116 } 4117 4118 static const char *no_comm = "(no comm)"; 4119 4120 static u64 hist_field_execname(struct hist_field *hist_field, 4121 struct tracing_map_elt *elt, 4122 struct trace_buffer *buffer, 4123 struct ring_buffer_event *rbe, 4124 void *event) 4125 { 4126 struct hist_elt_data *elt_data; 4127 4128 if (WARN_ON_ONCE(!elt)) 4129 return (u64)(unsigned long)no_comm; 4130 4131 elt_data = elt->private_data; 4132 4133 if (WARN_ON_ONCE(!elt_data->comm)) 4134 return (u64)(unsigned long)no_comm; 4135 4136 return (u64)(unsigned long)(elt_data->comm); 4137 } 4138 4139 /* Convert a var that points to common_pid.execname to a string */ 4140 static void update_var_execname(struct hist_field *hist_field) 4141 { 4142 hist_field->flags = HIST_FIELD_FL_STRING | HIST_FIELD_FL_VAR | 4143 HIST_FIELD_FL_EXECNAME; 4144 hist_field->size = MAX_FILTER_STR_VAL; 4145 hist_field->is_signed = 0; 4146 4147 kfree_const(hist_field->type); 4148 hist_field->type = "char[]"; 4149 4150 hist_field->fn = hist_field_execname; 4151 } 4152 4153 static int create_var_field(struct hist_trigger_data *hist_data, 4154 unsigned int val_idx, 4155 struct trace_event_file *file, 4156 char *var_name, char *expr_str) 4157 { 4158 struct trace_array *tr = hist_data->event_file->tr; 4159 unsigned long flags = 0; 4160 int ret; 4161 4162 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX)) 4163 return -EINVAL; 4164 4165 if (find_var(hist_data, file, var_name) && !hist_data->remove) { 4166 hist_err(tr, HIST_ERR_DUPLICATE_VAR, errpos(var_name)); 4167 return -EINVAL; 4168 } 4169 4170 flags |= HIST_FIELD_FL_VAR; 4171 hist_data->n_vars++; 4172 if (WARN_ON(hist_data->n_vars > TRACING_MAP_VARS_MAX)) 4173 return -EINVAL; 4174 4175 ret = __create_val_field(hist_data, val_idx, file, var_name, expr_str, flags); 4176 4177 if (!ret && hist_data->fields[val_idx]->flags & HIST_FIELD_FL_EXECNAME) 4178 update_var_execname(hist_data->fields[val_idx]); 4179 4180 if (!ret && hist_data->fields[val_idx]->flags & HIST_FIELD_FL_STRING) 4181 hist_data->fields[val_idx]->var_str_idx = hist_data->n_var_str++; 4182 4183 return ret; 4184 } 4185 4186 static int create_val_fields(struct hist_trigger_data *hist_data, 4187 struct trace_event_file *file) 4188 { 4189 char *fields_str, *field_str; 4190 unsigned int i, j = 1; 4191 int ret; 4192 4193 ret = create_hitcount_val(hist_data); 4194 if (ret) 4195 goto out; 4196 4197 fields_str = hist_data->attrs->vals_str; 4198 if (!fields_str) 4199 goto out; 4200 4201 for (i = 0, j = 1; i < TRACING_MAP_VALS_MAX && 4202 j < TRACING_MAP_VALS_MAX; i++) { 4203 field_str = strsep(&fields_str, ","); 4204 if (!field_str) 4205 break; 4206 4207 if (strcmp(field_str, "hitcount") == 0) 4208 continue; 4209 4210 ret = create_val_field(hist_data, j++, file, field_str); 4211 if (ret) 4212 goto out; 4213 } 4214 4215 if (fields_str && (strcmp(fields_str, "hitcount") != 0)) 4216 ret = -EINVAL; 4217 out: 4218 return ret; 4219 } 4220 4221 static int create_key_field(struct hist_trigger_data *hist_data, 4222 unsigned int key_idx, 4223 unsigned int key_offset, 4224 struct trace_event_file *file, 4225 char *field_str) 4226 { 4227 struct trace_array *tr = hist_data->event_file->tr; 4228 struct hist_field *hist_field = NULL; 4229 unsigned long flags = 0; 4230 unsigned int key_size; 4231 int ret = 0, n_subexprs = 0; 4232 4233 if (WARN_ON(key_idx >= HIST_FIELDS_MAX)) 4234 return -EINVAL; 4235 4236 flags |= HIST_FIELD_FL_KEY; 4237 4238 if (strcmp(field_str, "stacktrace") == 0) { 4239 flags |= HIST_FIELD_FL_STACKTRACE; 4240 key_size = sizeof(unsigned long) * HIST_STACKTRACE_DEPTH; 4241 hist_field = create_hist_field(hist_data, NULL, flags, NULL); 4242 } else { 4243 hist_field = parse_expr(hist_data, file, field_str, flags, 4244 NULL, &n_subexprs); 4245 if (IS_ERR(hist_field)) { 4246 ret = PTR_ERR(hist_field); 4247 goto out; 4248 } 4249 4250 if (field_has_hist_vars(hist_field, 0)) { 4251 hist_err(tr, HIST_ERR_INVALID_REF_KEY, errpos(field_str)); 4252 destroy_hist_field(hist_field, 0); 4253 ret = -EINVAL; 4254 goto out; 4255 } 4256 4257 key_size = hist_field->size; 4258 } 4259 4260 hist_data->fields[key_idx] = hist_field; 4261 4262 key_size = ALIGN(key_size, sizeof(u64)); 4263 hist_data->fields[key_idx]->size = key_size; 4264 hist_data->fields[key_idx]->offset = key_offset; 4265 4266 hist_data->key_size += key_size; 4267 4268 if (hist_data->key_size > HIST_KEY_SIZE_MAX) { 4269 ret = -EINVAL; 4270 goto out; 4271 } 4272 4273 hist_data->n_keys++; 4274 hist_data->n_fields++; 4275 4276 if (WARN_ON(hist_data->n_keys > TRACING_MAP_KEYS_MAX)) 4277 return -EINVAL; 4278 4279 ret = key_size; 4280 out: 4281 return ret; 4282 } 4283 4284 static int create_key_fields(struct hist_trigger_data *hist_data, 4285 struct trace_event_file *file) 4286 { 4287 unsigned int i, key_offset = 0, n_vals = hist_data->n_vals; 4288 char *fields_str, *field_str; 4289 int ret = -EINVAL; 4290 4291 fields_str = hist_data->attrs->keys_str; 4292 if (!fields_str) 4293 goto out; 4294 4295 for (i = n_vals; i < n_vals + TRACING_MAP_KEYS_MAX; i++) { 4296 field_str = strsep(&fields_str, ","); 4297 if (!field_str) 4298 break; 4299 ret = create_key_field(hist_data, i, key_offset, 4300 file, field_str); 4301 if (ret < 0) 4302 goto out; 4303 key_offset += ret; 4304 } 4305 if (fields_str) { 4306 ret = -EINVAL; 4307 goto out; 4308 } 4309 ret = 0; 4310 out: 4311 return ret; 4312 } 4313 4314 static int create_var_fields(struct hist_trigger_data *hist_data, 4315 struct trace_event_file *file) 4316 { 4317 unsigned int i, j = hist_data->n_vals; 4318 int ret = 0; 4319 4320 unsigned int n_vars = hist_data->attrs->var_defs.n_vars; 4321 4322 for (i = 0; i < n_vars; i++) { 4323 char *var_name = hist_data->attrs->var_defs.name[i]; 4324 char *expr = hist_data->attrs->var_defs.expr[i]; 4325 4326 ret = create_var_field(hist_data, j++, file, var_name, expr); 4327 if (ret) 4328 goto out; 4329 } 4330 out: 4331 return ret; 4332 } 4333 4334 static void free_var_defs(struct hist_trigger_data *hist_data) 4335 { 4336 unsigned int i; 4337 4338 for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) { 4339 kfree(hist_data->attrs->var_defs.name[i]); 4340 kfree(hist_data->attrs->var_defs.expr[i]); 4341 } 4342 4343 hist_data->attrs->var_defs.n_vars = 0; 4344 } 4345 4346 static int parse_var_defs(struct hist_trigger_data *hist_data) 4347 { 4348 struct trace_array *tr = hist_data->event_file->tr; 4349 char *s, *str, *var_name, *field_str; 4350 unsigned int i, j, n_vars = 0; 4351 int ret = 0; 4352 4353 for (i = 0; i < hist_data->attrs->n_assignments; i++) { 4354 str = hist_data->attrs->assignment_str[i]; 4355 for (j = 0; j < TRACING_MAP_VARS_MAX; j++) { 4356 field_str = strsep(&str, ","); 4357 if (!field_str) 4358 break; 4359 4360 var_name = strsep(&field_str, "="); 4361 if (!var_name || !field_str) { 4362 hist_err(tr, HIST_ERR_MALFORMED_ASSIGNMENT, 4363 errpos(var_name)); 4364 ret = -EINVAL; 4365 goto free; 4366 } 4367 4368 if (n_vars == TRACING_MAP_VARS_MAX) { 4369 hist_err(tr, HIST_ERR_TOO_MANY_VARS, errpos(var_name)); 4370 ret = -EINVAL; 4371 goto free; 4372 } 4373 4374 s = kstrdup(var_name, GFP_KERNEL); 4375 if (!s) { 4376 ret = -ENOMEM; 4377 goto free; 4378 } 4379 hist_data->attrs->var_defs.name[n_vars] = s; 4380 4381 s = kstrdup(field_str, GFP_KERNEL); 4382 if (!s) { 4383 ret = -ENOMEM; 4384 goto free; 4385 } 4386 hist_data->attrs->var_defs.expr[n_vars++] = s; 4387 4388 hist_data->attrs->var_defs.n_vars = n_vars; 4389 } 4390 } 4391 4392 return ret; 4393 free: 4394 free_var_defs(hist_data); 4395 4396 return ret; 4397 } 4398 4399 static int create_hist_fields(struct hist_trigger_data *hist_data, 4400 struct trace_event_file *file) 4401 { 4402 int ret; 4403 4404 ret = parse_var_defs(hist_data); 4405 if (ret) 4406 goto out; 4407 4408 ret = create_val_fields(hist_data, file); 4409 if (ret) 4410 goto out; 4411 4412 ret = create_var_fields(hist_data, file); 4413 if (ret) 4414 goto out; 4415 4416 ret = create_key_fields(hist_data, file); 4417 if (ret) 4418 goto out; 4419 out: 4420 free_var_defs(hist_data); 4421 4422 return ret; 4423 } 4424 4425 static int is_descending(struct trace_array *tr, const char *str) 4426 { 4427 if (!str) 4428 return 0; 4429 4430 if (strcmp(str, "descending") == 0) 4431 return 1; 4432 4433 if (strcmp(str, "ascending") == 0) 4434 return 0; 4435 4436 hist_err(tr, HIST_ERR_INVALID_SORT_MODIFIER, errpos((char *)str)); 4437 4438 return -EINVAL; 4439 } 4440 4441 static int create_sort_keys(struct hist_trigger_data *hist_data) 4442 { 4443 struct trace_array *tr = hist_data->event_file->tr; 4444 char *fields_str = hist_data->attrs->sort_key_str; 4445 struct tracing_map_sort_key *sort_key; 4446 int descending, ret = 0; 4447 unsigned int i, j, k; 4448 4449 hist_data->n_sort_keys = 1; /* we always have at least one, hitcount */ 4450 4451 if (!fields_str) 4452 goto out; 4453 4454 for (i = 0; i < TRACING_MAP_SORT_KEYS_MAX; i++) { 4455 struct hist_field *hist_field; 4456 char *field_str, *field_name; 4457 const char *test_name; 4458 4459 sort_key = &hist_data->sort_keys[i]; 4460 4461 field_str = strsep(&fields_str, ","); 4462 if (!field_str) 4463 break; 4464 4465 if (!*field_str) { 4466 ret = -EINVAL; 4467 hist_err(tr, HIST_ERR_EMPTY_SORT_FIELD, errpos("sort=")); 4468 break; 4469 } 4470 4471 if ((i == TRACING_MAP_SORT_KEYS_MAX - 1) && fields_str) { 4472 hist_err(tr, HIST_ERR_TOO_MANY_SORT_FIELDS, errpos("sort=")); 4473 ret = -EINVAL; 4474 break; 4475 } 4476 4477 field_name = strsep(&field_str, "."); 4478 if (!field_name || !*field_name) { 4479 ret = -EINVAL; 4480 hist_err(tr, HIST_ERR_EMPTY_SORT_FIELD, errpos("sort=")); 4481 break; 4482 } 4483 4484 if (strcmp(field_name, "hitcount") == 0) { 4485 descending = is_descending(tr, field_str); 4486 if (descending < 0) { 4487 ret = descending; 4488 break; 4489 } 4490 sort_key->descending = descending; 4491 continue; 4492 } 4493 4494 for (j = 1, k = 1; j < hist_data->n_fields; j++) { 4495 unsigned int idx; 4496 4497 hist_field = hist_data->fields[j]; 4498 if (hist_field->flags & HIST_FIELD_FL_VAR) 4499 continue; 4500 4501 idx = k++; 4502 4503 test_name = hist_field_name(hist_field, 0); 4504 4505 if (strcmp(field_name, test_name) == 0) { 4506 sort_key->field_idx = idx; 4507 descending = is_descending(tr, field_str); 4508 if (descending < 0) { 4509 ret = descending; 4510 goto out; 4511 } 4512 sort_key->descending = descending; 4513 break; 4514 } 4515 } 4516 if (j == hist_data->n_fields) { 4517 ret = -EINVAL; 4518 hist_err(tr, HIST_ERR_INVALID_SORT_FIELD, errpos(field_name)); 4519 break; 4520 } 4521 } 4522 4523 hist_data->n_sort_keys = i; 4524 out: 4525 return ret; 4526 } 4527 4528 static void destroy_actions(struct hist_trigger_data *hist_data) 4529 { 4530 unsigned int i; 4531 4532 for (i = 0; i < hist_data->n_actions; i++) { 4533 struct action_data *data = hist_data->actions[i]; 4534 4535 if (data->handler == HANDLER_ONMATCH) 4536 onmatch_destroy(data); 4537 else if (data->handler == HANDLER_ONMAX || 4538 data->handler == HANDLER_ONCHANGE) 4539 track_data_destroy(hist_data, data); 4540 else 4541 kfree(data); 4542 } 4543 } 4544 4545 static int parse_actions(struct hist_trigger_data *hist_data) 4546 { 4547 struct trace_array *tr = hist_data->event_file->tr; 4548 struct action_data *data; 4549 unsigned int i; 4550 int ret = 0; 4551 char *str; 4552 int len; 4553 4554 for (i = 0; i < hist_data->attrs->n_actions; i++) { 4555 str = hist_data->attrs->action_str[i]; 4556 4557 if ((len = str_has_prefix(str, "onmatch("))) { 4558 char *action_str = str + len; 4559 4560 data = onmatch_parse(tr, action_str); 4561 if (IS_ERR(data)) { 4562 ret = PTR_ERR(data); 4563 break; 4564 } 4565 } else if ((len = str_has_prefix(str, "onmax("))) { 4566 char *action_str = str + len; 4567 4568 data = track_data_parse(hist_data, action_str, 4569 HANDLER_ONMAX); 4570 if (IS_ERR(data)) { 4571 ret = PTR_ERR(data); 4572 break; 4573 } 4574 } else if ((len = str_has_prefix(str, "onchange("))) { 4575 char *action_str = str + len; 4576 4577 data = track_data_parse(hist_data, action_str, 4578 HANDLER_ONCHANGE); 4579 if (IS_ERR(data)) { 4580 ret = PTR_ERR(data); 4581 break; 4582 } 4583 } else { 4584 ret = -EINVAL; 4585 break; 4586 } 4587 4588 hist_data->actions[hist_data->n_actions++] = data; 4589 } 4590 4591 return ret; 4592 } 4593 4594 static int create_actions(struct hist_trigger_data *hist_data) 4595 { 4596 struct action_data *data; 4597 unsigned int i; 4598 int ret = 0; 4599 4600 for (i = 0; i < hist_data->attrs->n_actions; i++) { 4601 data = hist_data->actions[i]; 4602 4603 if (data->handler == HANDLER_ONMATCH) { 4604 ret = onmatch_create(hist_data, data); 4605 if (ret) 4606 break; 4607 } else if (data->handler == HANDLER_ONMAX || 4608 data->handler == HANDLER_ONCHANGE) { 4609 ret = track_data_create(hist_data, data); 4610 if (ret) 4611 break; 4612 } else { 4613 ret = -EINVAL; 4614 break; 4615 } 4616 } 4617 4618 return ret; 4619 } 4620 4621 static void print_actions(struct seq_file *m, 4622 struct hist_trigger_data *hist_data, 4623 struct tracing_map_elt *elt) 4624 { 4625 unsigned int i; 4626 4627 for (i = 0; i < hist_data->n_actions; i++) { 4628 struct action_data *data = hist_data->actions[i]; 4629 4630 if (data->action == ACTION_SNAPSHOT) 4631 continue; 4632 4633 if (data->handler == HANDLER_ONMAX || 4634 data->handler == HANDLER_ONCHANGE) 4635 track_data_print(m, hist_data, elt, data); 4636 } 4637 } 4638 4639 static void print_action_spec(struct seq_file *m, 4640 struct hist_trigger_data *hist_data, 4641 struct action_data *data) 4642 { 4643 unsigned int i; 4644 4645 if (data->action == ACTION_SAVE) { 4646 for (i = 0; i < hist_data->n_save_vars; i++) { 4647 seq_printf(m, "%s", hist_data->save_vars[i]->var->var.name); 4648 if (i < hist_data->n_save_vars - 1) 4649 seq_puts(m, ","); 4650 } 4651 } else if (data->action == ACTION_TRACE) { 4652 if (data->use_trace_keyword) 4653 seq_printf(m, "%s", data->synth_event_name); 4654 for (i = 0; i < data->n_params; i++) { 4655 if (i || data->use_trace_keyword) 4656 seq_puts(m, ","); 4657 seq_printf(m, "%s", data->params[i]); 4658 } 4659 } 4660 } 4661 4662 static void print_track_data_spec(struct seq_file *m, 4663 struct hist_trigger_data *hist_data, 4664 struct action_data *data) 4665 { 4666 if (data->handler == HANDLER_ONMAX) 4667 seq_puts(m, ":onmax("); 4668 else if (data->handler == HANDLER_ONCHANGE) 4669 seq_puts(m, ":onchange("); 4670 seq_printf(m, "%s", data->track_data.var_str); 4671 seq_printf(m, ").%s(", data->action_name); 4672 4673 print_action_spec(m, hist_data, data); 4674 4675 seq_puts(m, ")"); 4676 } 4677 4678 static void print_onmatch_spec(struct seq_file *m, 4679 struct hist_trigger_data *hist_data, 4680 struct action_data *data) 4681 { 4682 seq_printf(m, ":onmatch(%s.%s).", data->match_data.event_system, 4683 data->match_data.event); 4684 4685 seq_printf(m, "%s(", data->action_name); 4686 4687 print_action_spec(m, hist_data, data); 4688 4689 seq_puts(m, ")"); 4690 } 4691 4692 static bool actions_match(struct hist_trigger_data *hist_data, 4693 struct hist_trigger_data *hist_data_test) 4694 { 4695 unsigned int i, j; 4696 4697 if (hist_data->n_actions != hist_data_test->n_actions) 4698 return false; 4699 4700 for (i = 0; i < hist_data->n_actions; i++) { 4701 struct action_data *data = hist_data->actions[i]; 4702 struct action_data *data_test = hist_data_test->actions[i]; 4703 char *action_name, *action_name_test; 4704 4705 if (data->handler != data_test->handler) 4706 return false; 4707 if (data->action != data_test->action) 4708 return false; 4709 4710 if (data->n_params != data_test->n_params) 4711 return false; 4712 4713 for (j = 0; j < data->n_params; j++) { 4714 if (strcmp(data->params[j], data_test->params[j]) != 0) 4715 return false; 4716 } 4717 4718 if (data->use_trace_keyword) 4719 action_name = data->synth_event_name; 4720 else 4721 action_name = data->action_name; 4722 4723 if (data_test->use_trace_keyword) 4724 action_name_test = data_test->synth_event_name; 4725 else 4726 action_name_test = data_test->action_name; 4727 4728 if (strcmp(action_name, action_name_test) != 0) 4729 return false; 4730 4731 if (data->handler == HANDLER_ONMATCH) { 4732 if (strcmp(data->match_data.event_system, 4733 data_test->match_data.event_system) != 0) 4734 return false; 4735 if (strcmp(data->match_data.event, 4736 data_test->match_data.event) != 0) 4737 return false; 4738 } else if (data->handler == HANDLER_ONMAX || 4739 data->handler == HANDLER_ONCHANGE) { 4740 if (strcmp(data->track_data.var_str, 4741 data_test->track_data.var_str) != 0) 4742 return false; 4743 } 4744 } 4745 4746 return true; 4747 } 4748 4749 4750 static void print_actions_spec(struct seq_file *m, 4751 struct hist_trigger_data *hist_data) 4752 { 4753 unsigned int i; 4754 4755 for (i = 0; i < hist_data->n_actions; i++) { 4756 struct action_data *data = hist_data->actions[i]; 4757 4758 if (data->handler == HANDLER_ONMATCH) 4759 print_onmatch_spec(m, hist_data, data); 4760 else if (data->handler == HANDLER_ONMAX || 4761 data->handler == HANDLER_ONCHANGE) 4762 print_track_data_spec(m, hist_data, data); 4763 } 4764 } 4765 4766 static void destroy_field_var_hists(struct hist_trigger_data *hist_data) 4767 { 4768 unsigned int i; 4769 4770 for (i = 0; i < hist_data->n_field_var_hists; i++) { 4771 kfree(hist_data->field_var_hists[i]->cmd); 4772 kfree(hist_data->field_var_hists[i]); 4773 } 4774 } 4775 4776 static void destroy_hist_data(struct hist_trigger_data *hist_data) 4777 { 4778 if (!hist_data) 4779 return; 4780 4781 destroy_hist_trigger_attrs(hist_data->attrs); 4782 destroy_hist_fields(hist_data); 4783 tracing_map_destroy(hist_data->map); 4784 4785 destroy_actions(hist_data); 4786 destroy_field_vars(hist_data); 4787 destroy_field_var_hists(hist_data); 4788 4789 kfree(hist_data); 4790 } 4791 4792 static int create_tracing_map_fields(struct hist_trigger_data *hist_data) 4793 { 4794 struct tracing_map *map = hist_data->map; 4795 struct ftrace_event_field *field; 4796 struct hist_field *hist_field; 4797 int i, idx = 0; 4798 4799 for_each_hist_field(i, hist_data) { 4800 hist_field = hist_data->fields[i]; 4801 if (hist_field->flags & HIST_FIELD_FL_KEY) { 4802 tracing_map_cmp_fn_t cmp_fn; 4803 4804 field = hist_field->field; 4805 4806 if (hist_field->flags & HIST_FIELD_FL_STACKTRACE) 4807 cmp_fn = tracing_map_cmp_none; 4808 else if (!field) 4809 cmp_fn = tracing_map_cmp_num(hist_field->size, 4810 hist_field->is_signed); 4811 else if (is_string_field(field)) 4812 cmp_fn = tracing_map_cmp_string; 4813 else 4814 cmp_fn = tracing_map_cmp_num(field->size, 4815 field->is_signed); 4816 idx = tracing_map_add_key_field(map, 4817 hist_field->offset, 4818 cmp_fn); 4819 } else if (!(hist_field->flags & HIST_FIELD_FL_VAR)) 4820 idx = tracing_map_add_sum_field(map); 4821 4822 if (idx < 0) 4823 return idx; 4824 4825 if (hist_field->flags & HIST_FIELD_FL_VAR) { 4826 idx = tracing_map_add_var(map); 4827 if (idx < 0) 4828 return idx; 4829 hist_field->var.idx = idx; 4830 hist_field->var.hist_data = hist_data; 4831 } 4832 } 4833 4834 return 0; 4835 } 4836 4837 static struct hist_trigger_data * 4838 create_hist_data(unsigned int map_bits, 4839 struct hist_trigger_attrs *attrs, 4840 struct trace_event_file *file, 4841 bool remove) 4842 { 4843 const struct tracing_map_ops *map_ops = NULL; 4844 struct hist_trigger_data *hist_data; 4845 int ret = 0; 4846 4847 hist_data = kzalloc(sizeof(*hist_data), GFP_KERNEL); 4848 if (!hist_data) 4849 return ERR_PTR(-ENOMEM); 4850 4851 hist_data->attrs = attrs; 4852 hist_data->remove = remove; 4853 hist_data->event_file = file; 4854 4855 ret = parse_actions(hist_data); 4856 if (ret) 4857 goto free; 4858 4859 ret = create_hist_fields(hist_data, file); 4860 if (ret) 4861 goto free; 4862 4863 ret = create_sort_keys(hist_data); 4864 if (ret) 4865 goto free; 4866 4867 map_ops = &hist_trigger_elt_data_ops; 4868 4869 hist_data->map = tracing_map_create(map_bits, hist_data->key_size, 4870 map_ops, hist_data); 4871 if (IS_ERR(hist_data->map)) { 4872 ret = PTR_ERR(hist_data->map); 4873 hist_data->map = NULL; 4874 goto free; 4875 } 4876 4877 ret = create_tracing_map_fields(hist_data); 4878 if (ret) 4879 goto free; 4880 out: 4881 return hist_data; 4882 free: 4883 hist_data->attrs = NULL; 4884 4885 destroy_hist_data(hist_data); 4886 4887 hist_data = ERR_PTR(ret); 4888 4889 goto out; 4890 } 4891 4892 static void hist_trigger_elt_update(struct hist_trigger_data *hist_data, 4893 struct tracing_map_elt *elt, 4894 struct trace_buffer *buffer, void *rec, 4895 struct ring_buffer_event *rbe, 4896 u64 *var_ref_vals) 4897 { 4898 struct hist_elt_data *elt_data; 4899 struct hist_field *hist_field; 4900 unsigned int i, var_idx; 4901 u64 hist_val; 4902 4903 elt_data = elt->private_data; 4904 elt_data->var_ref_vals = var_ref_vals; 4905 4906 for_each_hist_val_field(i, hist_data) { 4907 hist_field = hist_data->fields[i]; 4908 hist_val = hist_field->fn(hist_field, elt, buffer, rbe, rec); 4909 if (hist_field->flags & HIST_FIELD_FL_VAR) { 4910 var_idx = hist_field->var.idx; 4911 4912 if (hist_field->flags & HIST_FIELD_FL_STRING) { 4913 unsigned int str_start, var_str_idx, idx; 4914 char *str, *val_str; 4915 4916 str_start = hist_data->n_field_var_str + 4917 hist_data->n_save_var_str; 4918 var_str_idx = hist_field->var_str_idx; 4919 idx = str_start + var_str_idx; 4920 4921 str = elt_data->field_var_str[idx]; 4922 val_str = (char *)(uintptr_t)hist_val; 4923 strscpy(str, val_str, STR_VAR_LEN_MAX); 4924 4925 hist_val = (u64)(uintptr_t)str; 4926 } 4927 tracing_map_set_var(elt, var_idx, hist_val); 4928 continue; 4929 } 4930 tracing_map_update_sum(elt, i, hist_val); 4931 } 4932 4933 for_each_hist_key_field(i, hist_data) { 4934 hist_field = hist_data->fields[i]; 4935 if (hist_field->flags & HIST_FIELD_FL_VAR) { 4936 hist_val = hist_field->fn(hist_field, elt, buffer, rbe, rec); 4937 var_idx = hist_field->var.idx; 4938 tracing_map_set_var(elt, var_idx, hist_val); 4939 } 4940 } 4941 4942 update_field_vars(hist_data, elt, buffer, rbe, rec); 4943 } 4944 4945 static inline void add_to_key(char *compound_key, void *key, 4946 struct hist_field *key_field, void *rec) 4947 { 4948 size_t size = key_field->size; 4949 4950 if (key_field->flags & HIST_FIELD_FL_STRING) { 4951 struct ftrace_event_field *field; 4952 4953 field = key_field->field; 4954 if (field->filter_type == FILTER_DYN_STRING) 4955 size = *(u32 *)(rec + field->offset) >> 16; 4956 else if (field->filter_type == FILTER_STATIC_STRING) 4957 size = field->size; 4958 4959 /* ensure NULL-termination */ 4960 if (size > key_field->size - 1) 4961 size = key_field->size - 1; 4962 4963 strncpy(compound_key + key_field->offset, (char *)key, size); 4964 } else 4965 memcpy(compound_key + key_field->offset, key, size); 4966 } 4967 4968 static void 4969 hist_trigger_actions(struct hist_trigger_data *hist_data, 4970 struct tracing_map_elt *elt, 4971 struct trace_buffer *buffer, void *rec, 4972 struct ring_buffer_event *rbe, void *key, 4973 u64 *var_ref_vals) 4974 { 4975 struct action_data *data; 4976 unsigned int i; 4977 4978 for (i = 0; i < hist_data->n_actions; i++) { 4979 data = hist_data->actions[i]; 4980 data->fn(hist_data, elt, buffer, rec, rbe, key, data, var_ref_vals); 4981 } 4982 } 4983 4984 static void event_hist_trigger(struct event_trigger_data *data, 4985 struct trace_buffer *buffer, void *rec, 4986 struct ring_buffer_event *rbe) 4987 { 4988 struct hist_trigger_data *hist_data = data->private_data; 4989 bool use_compound_key = (hist_data->n_keys > 1); 4990 unsigned long entries[HIST_STACKTRACE_DEPTH]; 4991 u64 var_ref_vals[TRACING_MAP_VARS_MAX]; 4992 char compound_key[HIST_KEY_SIZE_MAX]; 4993 struct tracing_map_elt *elt = NULL; 4994 struct hist_field *key_field; 4995 u64 field_contents; 4996 void *key = NULL; 4997 unsigned int i; 4998 4999 memset(compound_key, 0, hist_data->key_size); 5000 5001 for_each_hist_key_field(i, hist_data) { 5002 key_field = hist_data->fields[i]; 5003 5004 if (key_field->flags & HIST_FIELD_FL_STACKTRACE) { 5005 memset(entries, 0, HIST_STACKTRACE_SIZE); 5006 stack_trace_save(entries, HIST_STACKTRACE_DEPTH, 5007 HIST_STACKTRACE_SKIP); 5008 key = entries; 5009 } else { 5010 field_contents = key_field->fn(key_field, elt, buffer, rbe, rec); 5011 if (key_field->flags & HIST_FIELD_FL_STRING) { 5012 key = (void *)(unsigned long)field_contents; 5013 use_compound_key = true; 5014 } else 5015 key = (void *)&field_contents; 5016 } 5017 5018 if (use_compound_key) 5019 add_to_key(compound_key, key, key_field, rec); 5020 } 5021 5022 if (use_compound_key) 5023 key = compound_key; 5024 5025 if (hist_data->n_var_refs && 5026 !resolve_var_refs(hist_data, key, var_ref_vals, false)) 5027 return; 5028 5029 elt = tracing_map_insert(hist_data->map, key); 5030 if (!elt) 5031 return; 5032 5033 hist_trigger_elt_update(hist_data, elt, buffer, rec, rbe, var_ref_vals); 5034 5035 if (resolve_var_refs(hist_data, key, var_ref_vals, true)) 5036 hist_trigger_actions(hist_data, elt, buffer, rec, rbe, key, var_ref_vals); 5037 } 5038 5039 static void hist_trigger_stacktrace_print(struct seq_file *m, 5040 unsigned long *stacktrace_entries, 5041 unsigned int max_entries) 5042 { 5043 unsigned int spaces = 8; 5044 unsigned int i; 5045 5046 for (i = 0; i < max_entries; i++) { 5047 if (!stacktrace_entries[i]) 5048 return; 5049 5050 seq_printf(m, "%*c", 1 + spaces, ' '); 5051 seq_printf(m, "%pS\n", (void*)stacktrace_entries[i]); 5052 } 5053 } 5054 5055 static void hist_trigger_print_key(struct seq_file *m, 5056 struct hist_trigger_data *hist_data, 5057 void *key, 5058 struct tracing_map_elt *elt) 5059 { 5060 struct hist_field *key_field; 5061 bool multiline = false; 5062 const char *field_name; 5063 unsigned int i; 5064 u64 uval; 5065 5066 seq_puts(m, "{ "); 5067 5068 for_each_hist_key_field(i, hist_data) { 5069 key_field = hist_data->fields[i]; 5070 5071 if (i > hist_data->n_vals) 5072 seq_puts(m, ", "); 5073 5074 field_name = hist_field_name(key_field, 0); 5075 5076 if (key_field->flags & HIST_FIELD_FL_HEX) { 5077 uval = *(u64 *)(key + key_field->offset); 5078 seq_printf(m, "%s: %llx", field_name, uval); 5079 } else if (key_field->flags & HIST_FIELD_FL_SYM) { 5080 uval = *(u64 *)(key + key_field->offset); 5081 seq_printf(m, "%s: [%llx] %-45ps", field_name, 5082 uval, (void *)(uintptr_t)uval); 5083 } else if (key_field->flags & HIST_FIELD_FL_SYM_OFFSET) { 5084 uval = *(u64 *)(key + key_field->offset); 5085 seq_printf(m, "%s: [%llx] %-55pS", field_name, 5086 uval, (void *)(uintptr_t)uval); 5087 } else if (key_field->flags & HIST_FIELD_FL_EXECNAME) { 5088 struct hist_elt_data *elt_data = elt->private_data; 5089 char *comm; 5090 5091 if (WARN_ON_ONCE(!elt_data)) 5092 return; 5093 5094 comm = elt_data->comm; 5095 5096 uval = *(u64 *)(key + key_field->offset); 5097 seq_printf(m, "%s: %-16s[%10llu]", field_name, 5098 comm, uval); 5099 } else if (key_field->flags & HIST_FIELD_FL_SYSCALL) { 5100 const char *syscall_name; 5101 5102 uval = *(u64 *)(key + key_field->offset); 5103 syscall_name = get_syscall_name(uval); 5104 if (!syscall_name) 5105 syscall_name = "unknown_syscall"; 5106 5107 seq_printf(m, "%s: %-30s[%3llu]", field_name, 5108 syscall_name, uval); 5109 } else if (key_field->flags & HIST_FIELD_FL_STACKTRACE) { 5110 seq_puts(m, "stacktrace:\n"); 5111 hist_trigger_stacktrace_print(m, 5112 key + key_field->offset, 5113 HIST_STACKTRACE_DEPTH); 5114 multiline = true; 5115 } else if (key_field->flags & HIST_FIELD_FL_LOG2) { 5116 seq_printf(m, "%s: ~ 2^%-2llu", field_name, 5117 *(u64 *)(key + key_field->offset)); 5118 } else if (key_field->flags & HIST_FIELD_FL_BUCKET) { 5119 unsigned long buckets = key_field->buckets; 5120 uval = *(u64 *)(key + key_field->offset); 5121 seq_printf(m, "%s: ~ %llu-%llu", field_name, 5122 uval, uval + buckets -1); 5123 } else if (key_field->flags & HIST_FIELD_FL_STRING) { 5124 seq_printf(m, "%s: %-50s", field_name, 5125 (char *)(key + key_field->offset)); 5126 } else { 5127 uval = *(u64 *)(key + key_field->offset); 5128 seq_printf(m, "%s: %10llu", field_name, uval); 5129 } 5130 } 5131 5132 if (!multiline) 5133 seq_puts(m, " "); 5134 5135 seq_puts(m, "}"); 5136 } 5137 5138 static void hist_trigger_entry_print(struct seq_file *m, 5139 struct hist_trigger_data *hist_data, 5140 void *key, 5141 struct tracing_map_elt *elt) 5142 { 5143 const char *field_name; 5144 unsigned int i; 5145 5146 hist_trigger_print_key(m, hist_data, key, elt); 5147 5148 seq_printf(m, " hitcount: %10llu", 5149 tracing_map_read_sum(elt, HITCOUNT_IDX)); 5150 5151 for (i = 1; i < hist_data->n_vals; i++) { 5152 field_name = hist_field_name(hist_data->fields[i], 0); 5153 5154 if (hist_data->fields[i]->flags & HIST_FIELD_FL_VAR || 5155 hist_data->fields[i]->flags & HIST_FIELD_FL_EXPR) 5156 continue; 5157 5158 if (hist_data->fields[i]->flags & HIST_FIELD_FL_HEX) { 5159 seq_printf(m, " %s: %10llx", field_name, 5160 tracing_map_read_sum(elt, i)); 5161 } else { 5162 seq_printf(m, " %s: %10llu", field_name, 5163 tracing_map_read_sum(elt, i)); 5164 } 5165 } 5166 5167 print_actions(m, hist_data, elt); 5168 5169 seq_puts(m, "\n"); 5170 } 5171 5172 static int print_entries(struct seq_file *m, 5173 struct hist_trigger_data *hist_data) 5174 { 5175 struct tracing_map_sort_entry **sort_entries = NULL; 5176 struct tracing_map *map = hist_data->map; 5177 int i, n_entries; 5178 5179 n_entries = tracing_map_sort_entries(map, hist_data->sort_keys, 5180 hist_data->n_sort_keys, 5181 &sort_entries); 5182 if (n_entries < 0) 5183 return n_entries; 5184 5185 for (i = 0; i < n_entries; i++) 5186 hist_trigger_entry_print(m, hist_data, 5187 sort_entries[i]->key, 5188 sort_entries[i]->elt); 5189 5190 tracing_map_destroy_sort_entries(sort_entries, n_entries); 5191 5192 return n_entries; 5193 } 5194 5195 static void hist_trigger_show(struct seq_file *m, 5196 struct event_trigger_data *data, int n) 5197 { 5198 struct hist_trigger_data *hist_data; 5199 int n_entries; 5200 5201 if (n > 0) 5202 seq_puts(m, "\n\n"); 5203 5204 seq_puts(m, "# event histogram\n#\n# trigger info: "); 5205 data->ops->print(m, data->ops, data); 5206 seq_puts(m, "#\n\n"); 5207 5208 hist_data = data->private_data; 5209 n_entries = print_entries(m, hist_data); 5210 if (n_entries < 0) 5211 n_entries = 0; 5212 5213 track_data_snapshot_print(m, hist_data); 5214 5215 seq_printf(m, "\nTotals:\n Hits: %llu\n Entries: %u\n Dropped: %llu\n", 5216 (u64)atomic64_read(&hist_data->map->hits), 5217 n_entries, (u64)atomic64_read(&hist_data->map->drops)); 5218 } 5219 5220 static int hist_show(struct seq_file *m, void *v) 5221 { 5222 struct event_trigger_data *data; 5223 struct trace_event_file *event_file; 5224 int n = 0, ret = 0; 5225 5226 mutex_lock(&event_mutex); 5227 5228 event_file = event_file_data(m->private); 5229 if (unlikely(!event_file)) { 5230 ret = -ENODEV; 5231 goto out_unlock; 5232 } 5233 5234 list_for_each_entry(data, &event_file->triggers, list) { 5235 if (data->cmd_ops->trigger_type == ETT_EVENT_HIST) 5236 hist_trigger_show(m, data, n++); 5237 } 5238 5239 out_unlock: 5240 mutex_unlock(&event_mutex); 5241 5242 return ret; 5243 } 5244 5245 static int event_hist_open(struct inode *inode, struct file *file) 5246 { 5247 int ret; 5248 5249 ret = security_locked_down(LOCKDOWN_TRACEFS); 5250 if (ret) 5251 return ret; 5252 5253 return single_open(file, hist_show, file); 5254 } 5255 5256 const struct file_operations event_hist_fops = { 5257 .open = event_hist_open, 5258 .read = seq_read, 5259 .llseek = seq_lseek, 5260 .release = single_release, 5261 }; 5262 5263 #ifdef CONFIG_HIST_TRIGGERS_DEBUG 5264 static void hist_field_debug_show_flags(struct seq_file *m, 5265 unsigned long flags) 5266 { 5267 seq_puts(m, " flags:\n"); 5268 5269 if (flags & HIST_FIELD_FL_KEY) 5270 seq_puts(m, " HIST_FIELD_FL_KEY\n"); 5271 else if (flags & HIST_FIELD_FL_HITCOUNT) 5272 seq_puts(m, " VAL: HIST_FIELD_FL_HITCOUNT\n"); 5273 else if (flags & HIST_FIELD_FL_VAR) 5274 seq_puts(m, " HIST_FIELD_FL_VAR\n"); 5275 else if (flags & HIST_FIELD_FL_VAR_REF) 5276 seq_puts(m, " HIST_FIELD_FL_VAR_REF\n"); 5277 else 5278 seq_puts(m, " VAL: normal u64 value\n"); 5279 5280 if (flags & HIST_FIELD_FL_ALIAS) 5281 seq_puts(m, " HIST_FIELD_FL_ALIAS\n"); 5282 else if (flags & HIST_FIELD_FL_CONST) 5283 seq_puts(m, " HIST_FIELD_FL_CONST\n"); 5284 } 5285 5286 static int hist_field_debug_show(struct seq_file *m, 5287 struct hist_field *field, unsigned long flags) 5288 { 5289 if ((field->flags & flags) != flags) { 5290 seq_printf(m, "ERROR: bad flags - %lx\n", flags); 5291 return -EINVAL; 5292 } 5293 5294 hist_field_debug_show_flags(m, field->flags); 5295 if (field->field) 5296 seq_printf(m, " ftrace_event_field name: %s\n", 5297 field->field->name); 5298 5299 if (field->flags & HIST_FIELD_FL_VAR) { 5300 seq_printf(m, " var.name: %s\n", field->var.name); 5301 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n", 5302 field->var.idx); 5303 } 5304 5305 if (field->flags & HIST_FIELD_FL_CONST) 5306 seq_printf(m, " constant: %llu\n", field->constant); 5307 5308 if (field->flags & HIST_FIELD_FL_ALIAS) 5309 seq_printf(m, " var_ref_idx (into hist_data->var_refs[]): %u\n", 5310 field->var_ref_idx); 5311 5312 if (field->flags & HIST_FIELD_FL_VAR_REF) { 5313 seq_printf(m, " name: %s\n", field->name); 5314 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n", 5315 field->var.idx); 5316 seq_printf(m, " var.hist_data: %p\n", field->var.hist_data); 5317 seq_printf(m, " var_ref_idx (into hist_data->var_refs[]): %u\n", 5318 field->var_ref_idx); 5319 if (field->system) 5320 seq_printf(m, " system: %s\n", field->system); 5321 if (field->event_name) 5322 seq_printf(m, " event_name: %s\n", field->event_name); 5323 } 5324 5325 seq_printf(m, " type: %s\n", field->type); 5326 seq_printf(m, " size: %u\n", field->size); 5327 seq_printf(m, " is_signed: %u\n", field->is_signed); 5328 5329 return 0; 5330 } 5331 5332 static int field_var_debug_show(struct seq_file *m, 5333 struct field_var *field_var, unsigned int i, 5334 bool save_vars) 5335 { 5336 const char *vars_name = save_vars ? "save_vars" : "field_vars"; 5337 struct hist_field *field; 5338 int ret = 0; 5339 5340 seq_printf(m, "\n hist_data->%s[%d]:\n", vars_name, i); 5341 5342 field = field_var->var; 5343 5344 seq_printf(m, "\n %s[%d].var:\n", vars_name, i); 5345 5346 hist_field_debug_show_flags(m, field->flags); 5347 seq_printf(m, " var.name: %s\n", field->var.name); 5348 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n", 5349 field->var.idx); 5350 5351 field = field_var->val; 5352 5353 seq_printf(m, "\n %s[%d].val:\n", vars_name, i); 5354 if (field->field) 5355 seq_printf(m, " ftrace_event_field name: %s\n", 5356 field->field->name); 5357 else { 5358 ret = -EINVAL; 5359 goto out; 5360 } 5361 5362 seq_printf(m, " type: %s\n", field->type); 5363 seq_printf(m, " size: %u\n", field->size); 5364 seq_printf(m, " is_signed: %u\n", field->is_signed); 5365 out: 5366 return ret; 5367 } 5368 5369 static int hist_action_debug_show(struct seq_file *m, 5370 struct action_data *data, int i) 5371 { 5372 int ret = 0; 5373 5374 if (data->handler == HANDLER_ONMAX || 5375 data->handler == HANDLER_ONCHANGE) { 5376 seq_printf(m, "\n hist_data->actions[%d].track_data.var_ref:\n", i); 5377 ret = hist_field_debug_show(m, data->track_data.var_ref, 5378 HIST_FIELD_FL_VAR_REF); 5379 if (ret) 5380 goto out; 5381 5382 seq_printf(m, "\n hist_data->actions[%d].track_data.track_var:\n", i); 5383 ret = hist_field_debug_show(m, data->track_data.track_var, 5384 HIST_FIELD_FL_VAR); 5385 if (ret) 5386 goto out; 5387 } 5388 5389 if (data->handler == HANDLER_ONMATCH) { 5390 seq_printf(m, "\n hist_data->actions[%d].match_data.event_system: %s\n", 5391 i, data->match_data.event_system); 5392 seq_printf(m, " hist_data->actions[%d].match_data.event: %s\n", 5393 i, data->match_data.event); 5394 } 5395 out: 5396 return ret; 5397 } 5398 5399 static int hist_actions_debug_show(struct seq_file *m, 5400 struct hist_trigger_data *hist_data) 5401 { 5402 int i, ret = 0; 5403 5404 if (hist_data->n_actions) 5405 seq_puts(m, "\n action tracking variables (for onmax()/onchange()/onmatch()):\n"); 5406 5407 for (i = 0; i < hist_data->n_actions; i++) { 5408 struct action_data *action = hist_data->actions[i]; 5409 5410 ret = hist_action_debug_show(m, action, i); 5411 if (ret) 5412 goto out; 5413 } 5414 5415 if (hist_data->n_save_vars) 5416 seq_puts(m, "\n save action variables (save() params):\n"); 5417 5418 for (i = 0; i < hist_data->n_save_vars; i++) { 5419 ret = field_var_debug_show(m, hist_data->save_vars[i], i, true); 5420 if (ret) 5421 goto out; 5422 } 5423 out: 5424 return ret; 5425 } 5426 5427 static void hist_trigger_debug_show(struct seq_file *m, 5428 struct event_trigger_data *data, int n) 5429 { 5430 struct hist_trigger_data *hist_data; 5431 int i, ret; 5432 5433 if (n > 0) 5434 seq_puts(m, "\n\n"); 5435 5436 seq_puts(m, "# event histogram\n#\n# trigger info: "); 5437 data->ops->print(m, data->ops, data); 5438 seq_puts(m, "#\n\n"); 5439 5440 hist_data = data->private_data; 5441 5442 seq_printf(m, "hist_data: %p\n\n", hist_data); 5443 seq_printf(m, " n_vals: %u\n", hist_data->n_vals); 5444 seq_printf(m, " n_keys: %u\n", hist_data->n_keys); 5445 seq_printf(m, " n_fields: %u\n", hist_data->n_fields); 5446 5447 seq_puts(m, "\n val fields:\n\n"); 5448 5449 seq_puts(m, " hist_data->fields[0]:\n"); 5450 ret = hist_field_debug_show(m, hist_data->fields[0], 5451 HIST_FIELD_FL_HITCOUNT); 5452 if (ret) 5453 return; 5454 5455 for (i = 1; i < hist_data->n_vals; i++) { 5456 seq_printf(m, "\n hist_data->fields[%d]:\n", i); 5457 ret = hist_field_debug_show(m, hist_data->fields[i], 0); 5458 if (ret) 5459 return; 5460 } 5461 5462 seq_puts(m, "\n key fields:\n"); 5463 5464 for (i = hist_data->n_vals; i < hist_data->n_fields; i++) { 5465 seq_printf(m, "\n hist_data->fields[%d]:\n", i); 5466 ret = hist_field_debug_show(m, hist_data->fields[i], 5467 HIST_FIELD_FL_KEY); 5468 if (ret) 5469 return; 5470 } 5471 5472 if (hist_data->n_var_refs) 5473 seq_puts(m, "\n variable reference fields:\n"); 5474 5475 for (i = 0; i < hist_data->n_var_refs; i++) { 5476 seq_printf(m, "\n hist_data->var_refs[%d]:\n", i); 5477 ret = hist_field_debug_show(m, hist_data->var_refs[i], 5478 HIST_FIELD_FL_VAR_REF); 5479 if (ret) 5480 return; 5481 } 5482 5483 if (hist_data->n_field_vars) 5484 seq_puts(m, "\n field variables:\n"); 5485 5486 for (i = 0; i < hist_data->n_field_vars; i++) { 5487 ret = field_var_debug_show(m, hist_data->field_vars[i], i, false); 5488 if (ret) 5489 return; 5490 } 5491 5492 ret = hist_actions_debug_show(m, hist_data); 5493 if (ret) 5494 return; 5495 } 5496 5497 static int hist_debug_show(struct seq_file *m, void *v) 5498 { 5499 struct event_trigger_data *data; 5500 struct trace_event_file *event_file; 5501 int n = 0, ret = 0; 5502 5503 mutex_lock(&event_mutex); 5504 5505 event_file = event_file_data(m->private); 5506 if (unlikely(!event_file)) { 5507 ret = -ENODEV; 5508 goto out_unlock; 5509 } 5510 5511 list_for_each_entry(data, &event_file->triggers, list) { 5512 if (data->cmd_ops->trigger_type == ETT_EVENT_HIST) 5513 hist_trigger_debug_show(m, data, n++); 5514 } 5515 5516 out_unlock: 5517 mutex_unlock(&event_mutex); 5518 5519 return ret; 5520 } 5521 5522 static int event_hist_debug_open(struct inode *inode, struct file *file) 5523 { 5524 int ret; 5525 5526 ret = security_locked_down(LOCKDOWN_TRACEFS); 5527 if (ret) 5528 return ret; 5529 5530 return single_open(file, hist_debug_show, file); 5531 } 5532 5533 const struct file_operations event_hist_debug_fops = { 5534 .open = event_hist_debug_open, 5535 .read = seq_read, 5536 .llseek = seq_lseek, 5537 .release = single_release, 5538 }; 5539 #endif 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, "common_cpu"); 5550 else if (hist_field->flags & HIST_FIELD_FL_CONST) 5551 seq_printf(m, "%llu", hist_field->constant); 5552 else if (field_name) { 5553 if (hist_field->flags & HIST_FIELD_FL_VAR_REF || 5554 hist_field->flags & HIST_FIELD_FL_ALIAS) 5555 seq_putc(m, '$'); 5556 seq_printf(m, "%s", field_name); 5557 } else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP) 5558 seq_puts(m, "common_timestamp"); 5559 5560 if (hist_field->flags) { 5561 if (!(hist_field->flags & HIST_FIELD_FL_VAR_REF) && 5562 !(hist_field->flags & HIST_FIELD_FL_EXPR)) { 5563 const char *flags = get_hist_field_flags(hist_field); 5564 5565 if (flags) 5566 seq_printf(m, ".%s", flags); 5567 } 5568 } 5569 if (hist_field->buckets) 5570 seq_printf(m, "=%ld", hist_field->buckets); 5571 } 5572 5573 static int event_hist_trigger_print(struct seq_file *m, 5574 struct event_trigger_ops *ops, 5575 struct event_trigger_data *data) 5576 { 5577 struct hist_trigger_data *hist_data = data->private_data; 5578 struct hist_field *field; 5579 bool have_var = false; 5580 unsigned int i; 5581 5582 seq_puts(m, "hist:"); 5583 5584 if (data->name) 5585 seq_printf(m, "%s:", data->name); 5586 5587 seq_puts(m, "keys="); 5588 5589 for_each_hist_key_field(i, hist_data) { 5590 field = hist_data->fields[i]; 5591 5592 if (i > hist_data->n_vals) 5593 seq_puts(m, ","); 5594 5595 if (field->flags & HIST_FIELD_FL_STACKTRACE) 5596 seq_puts(m, "stacktrace"); 5597 else 5598 hist_field_print(m, field); 5599 } 5600 5601 seq_puts(m, ":vals="); 5602 5603 for_each_hist_val_field(i, hist_data) { 5604 field = hist_data->fields[i]; 5605 if (field->flags & HIST_FIELD_FL_VAR) { 5606 have_var = true; 5607 continue; 5608 } 5609 5610 if (i == HITCOUNT_IDX) 5611 seq_puts(m, "hitcount"); 5612 else { 5613 seq_puts(m, ","); 5614 hist_field_print(m, field); 5615 } 5616 } 5617 5618 if (have_var) { 5619 unsigned int n = 0; 5620 5621 seq_puts(m, ":"); 5622 5623 for_each_hist_val_field(i, hist_data) { 5624 field = hist_data->fields[i]; 5625 5626 if (field->flags & HIST_FIELD_FL_VAR) { 5627 if (n++) 5628 seq_puts(m, ","); 5629 hist_field_print(m, field); 5630 } 5631 } 5632 } 5633 5634 seq_puts(m, ":sort="); 5635 5636 for (i = 0; i < hist_data->n_sort_keys; i++) { 5637 struct tracing_map_sort_key *sort_key; 5638 unsigned int idx, first_key_idx; 5639 5640 /* skip VAR vals */ 5641 first_key_idx = hist_data->n_vals - hist_data->n_vars; 5642 5643 sort_key = &hist_data->sort_keys[i]; 5644 idx = sort_key->field_idx; 5645 5646 if (WARN_ON(idx >= HIST_FIELDS_MAX)) 5647 return -EINVAL; 5648 5649 if (i > 0) 5650 seq_puts(m, ","); 5651 5652 if (idx == HITCOUNT_IDX) 5653 seq_puts(m, "hitcount"); 5654 else { 5655 if (idx >= first_key_idx) 5656 idx += hist_data->n_vars; 5657 hist_field_print(m, hist_data->fields[idx]); 5658 } 5659 5660 if (sort_key->descending) 5661 seq_puts(m, ".descending"); 5662 } 5663 seq_printf(m, ":size=%u", (1 << hist_data->map->map_bits)); 5664 if (hist_data->enable_timestamps) 5665 seq_printf(m, ":clock=%s", hist_data->attrs->clock); 5666 5667 print_actions_spec(m, hist_data); 5668 5669 if (data->filter_str) 5670 seq_printf(m, " if %s", data->filter_str); 5671 5672 if (data->paused) 5673 seq_puts(m, " [paused]"); 5674 else 5675 seq_puts(m, " [active]"); 5676 5677 seq_putc(m, '\n'); 5678 5679 return 0; 5680 } 5681 5682 static int event_hist_trigger_init(struct event_trigger_ops *ops, 5683 struct event_trigger_data *data) 5684 { 5685 struct hist_trigger_data *hist_data = data->private_data; 5686 5687 if (!data->ref && hist_data->attrs->name) 5688 save_named_trigger(hist_data->attrs->name, data); 5689 5690 data->ref++; 5691 5692 return 0; 5693 } 5694 5695 static void unregister_field_var_hists(struct hist_trigger_data *hist_data) 5696 { 5697 struct trace_event_file *file; 5698 unsigned int i; 5699 char *cmd; 5700 int ret; 5701 5702 for (i = 0; i < hist_data->n_field_var_hists; i++) { 5703 file = hist_data->field_var_hists[i]->hist_data->event_file; 5704 cmd = hist_data->field_var_hists[i]->cmd; 5705 ret = event_hist_trigger_func(&trigger_hist_cmd, file, 5706 "!hist", "hist", cmd); 5707 WARN_ON_ONCE(ret < 0); 5708 } 5709 } 5710 5711 static void event_hist_trigger_free(struct event_trigger_ops *ops, 5712 struct event_trigger_data *data) 5713 { 5714 struct hist_trigger_data *hist_data = data->private_data; 5715 5716 if (WARN_ON_ONCE(data->ref <= 0)) 5717 return; 5718 5719 data->ref--; 5720 if (!data->ref) { 5721 if (data->name) 5722 del_named_trigger(data); 5723 5724 trigger_data_free(data); 5725 5726 remove_hist_vars(hist_data); 5727 5728 unregister_field_var_hists(hist_data); 5729 5730 destroy_hist_data(hist_data); 5731 } 5732 } 5733 5734 static struct event_trigger_ops event_hist_trigger_ops = { 5735 .func = event_hist_trigger, 5736 .print = event_hist_trigger_print, 5737 .init = event_hist_trigger_init, 5738 .free = event_hist_trigger_free, 5739 }; 5740 5741 static int event_hist_trigger_named_init(struct event_trigger_ops *ops, 5742 struct event_trigger_data *data) 5743 { 5744 data->ref++; 5745 5746 save_named_trigger(data->named_data->name, data); 5747 5748 event_hist_trigger_init(ops, data->named_data); 5749 5750 return 0; 5751 } 5752 5753 static void event_hist_trigger_named_free(struct event_trigger_ops *ops, 5754 struct event_trigger_data *data) 5755 { 5756 if (WARN_ON_ONCE(data->ref <= 0)) 5757 return; 5758 5759 event_hist_trigger_free(ops, data->named_data); 5760 5761 data->ref--; 5762 if (!data->ref) { 5763 del_named_trigger(data); 5764 trigger_data_free(data); 5765 } 5766 } 5767 5768 static struct event_trigger_ops event_hist_trigger_named_ops = { 5769 .func = event_hist_trigger, 5770 .print = event_hist_trigger_print, 5771 .init = event_hist_trigger_named_init, 5772 .free = event_hist_trigger_named_free, 5773 }; 5774 5775 static struct event_trigger_ops *event_hist_get_trigger_ops(char *cmd, 5776 char *param) 5777 { 5778 return &event_hist_trigger_ops; 5779 } 5780 5781 static void hist_clear(struct event_trigger_data *data) 5782 { 5783 struct hist_trigger_data *hist_data = data->private_data; 5784 5785 if (data->name) 5786 pause_named_trigger(data); 5787 5788 tracepoint_synchronize_unregister(); 5789 5790 tracing_map_clear(hist_data->map); 5791 5792 if (data->name) 5793 unpause_named_trigger(data); 5794 } 5795 5796 static bool compatible_field(struct ftrace_event_field *field, 5797 struct ftrace_event_field *test_field) 5798 { 5799 if (field == test_field) 5800 return true; 5801 if (field == NULL || test_field == NULL) 5802 return false; 5803 if (strcmp(field->name, test_field->name) != 0) 5804 return false; 5805 if (strcmp(field->type, test_field->type) != 0) 5806 return false; 5807 if (field->size != test_field->size) 5808 return false; 5809 if (field->is_signed != test_field->is_signed) 5810 return false; 5811 5812 return true; 5813 } 5814 5815 static bool hist_trigger_match(struct event_trigger_data *data, 5816 struct event_trigger_data *data_test, 5817 struct event_trigger_data *named_data, 5818 bool ignore_filter) 5819 { 5820 struct tracing_map_sort_key *sort_key, *sort_key_test; 5821 struct hist_trigger_data *hist_data, *hist_data_test; 5822 struct hist_field *key_field, *key_field_test; 5823 unsigned int i; 5824 5825 if (named_data && (named_data != data_test) && 5826 (named_data != data_test->named_data)) 5827 return false; 5828 5829 if (!named_data && is_named_trigger(data_test)) 5830 return false; 5831 5832 hist_data = data->private_data; 5833 hist_data_test = data_test->private_data; 5834 5835 if (hist_data->n_vals != hist_data_test->n_vals || 5836 hist_data->n_fields != hist_data_test->n_fields || 5837 hist_data->n_sort_keys != hist_data_test->n_sort_keys) 5838 return false; 5839 5840 if (!ignore_filter) { 5841 if ((data->filter_str && !data_test->filter_str) || 5842 (!data->filter_str && data_test->filter_str)) 5843 return false; 5844 } 5845 5846 for_each_hist_field(i, hist_data) { 5847 key_field = hist_data->fields[i]; 5848 key_field_test = hist_data_test->fields[i]; 5849 5850 if (key_field->flags != key_field_test->flags) 5851 return false; 5852 if (!compatible_field(key_field->field, key_field_test->field)) 5853 return false; 5854 if (key_field->offset != key_field_test->offset) 5855 return false; 5856 if (key_field->size != key_field_test->size) 5857 return false; 5858 if (key_field->is_signed != key_field_test->is_signed) 5859 return false; 5860 if (!!key_field->var.name != !!key_field_test->var.name) 5861 return false; 5862 if (key_field->var.name && 5863 strcmp(key_field->var.name, key_field_test->var.name) != 0) 5864 return false; 5865 } 5866 5867 for (i = 0; i < hist_data->n_sort_keys; i++) { 5868 sort_key = &hist_data->sort_keys[i]; 5869 sort_key_test = &hist_data_test->sort_keys[i]; 5870 5871 if (sort_key->field_idx != sort_key_test->field_idx || 5872 sort_key->descending != sort_key_test->descending) 5873 return false; 5874 } 5875 5876 if (!ignore_filter && data->filter_str && 5877 (strcmp(data->filter_str, data_test->filter_str) != 0)) 5878 return false; 5879 5880 if (!actions_match(hist_data, hist_data_test)) 5881 return false; 5882 5883 return true; 5884 } 5885 5886 static int hist_register_trigger(char *glob, struct event_trigger_ops *ops, 5887 struct event_trigger_data *data, 5888 struct trace_event_file *file) 5889 { 5890 struct hist_trigger_data *hist_data = data->private_data; 5891 struct event_trigger_data *test, *named_data = NULL; 5892 struct trace_array *tr = file->tr; 5893 int ret = 0; 5894 5895 if (hist_data->attrs->name) { 5896 named_data = find_named_trigger(hist_data->attrs->name); 5897 if (named_data) { 5898 if (!hist_trigger_match(data, named_data, named_data, 5899 true)) { 5900 hist_err(tr, HIST_ERR_NAMED_MISMATCH, errpos(hist_data->attrs->name)); 5901 ret = -EINVAL; 5902 goto out; 5903 } 5904 } 5905 } 5906 5907 if (hist_data->attrs->name && !named_data) 5908 goto new; 5909 5910 lockdep_assert_held(&event_mutex); 5911 5912 list_for_each_entry(test, &file->triggers, list) { 5913 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 5914 if (!hist_trigger_match(data, test, named_data, false)) 5915 continue; 5916 if (hist_data->attrs->pause) 5917 test->paused = true; 5918 else if (hist_data->attrs->cont) 5919 test->paused = false; 5920 else if (hist_data->attrs->clear) 5921 hist_clear(test); 5922 else { 5923 hist_err(tr, HIST_ERR_TRIGGER_EEXIST, 0); 5924 ret = -EEXIST; 5925 } 5926 goto out; 5927 } 5928 } 5929 new: 5930 if (hist_data->attrs->cont || hist_data->attrs->clear) { 5931 hist_err(tr, HIST_ERR_TRIGGER_ENOENT_CLEAR, 0); 5932 ret = -ENOENT; 5933 goto out; 5934 } 5935 5936 if (hist_data->attrs->pause) 5937 data->paused = true; 5938 5939 if (named_data) { 5940 data->private_data = named_data->private_data; 5941 set_named_trigger_data(data, named_data); 5942 data->ops = &event_hist_trigger_named_ops; 5943 } 5944 5945 if (data->ops->init) { 5946 ret = data->ops->init(data->ops, data); 5947 if (ret < 0) 5948 goto out; 5949 } 5950 5951 if (hist_data->enable_timestamps) { 5952 char *clock = hist_data->attrs->clock; 5953 5954 ret = tracing_set_clock(file->tr, hist_data->attrs->clock); 5955 if (ret) { 5956 hist_err(tr, HIST_ERR_SET_CLOCK_FAIL, errpos(clock)); 5957 goto out; 5958 } 5959 5960 tracing_set_filter_buffering(file->tr, true); 5961 } 5962 5963 if (named_data) 5964 destroy_hist_data(hist_data); 5965 5966 ret++; 5967 out: 5968 return ret; 5969 } 5970 5971 static int hist_trigger_enable(struct event_trigger_data *data, 5972 struct trace_event_file *file) 5973 { 5974 int ret = 0; 5975 5976 list_add_tail_rcu(&data->list, &file->triggers); 5977 5978 update_cond_flag(file); 5979 5980 if (trace_event_trigger_enable_disable(file, 1) < 0) { 5981 list_del_rcu(&data->list); 5982 update_cond_flag(file); 5983 ret--; 5984 } 5985 5986 return ret; 5987 } 5988 5989 static bool have_hist_trigger_match(struct event_trigger_data *data, 5990 struct trace_event_file *file) 5991 { 5992 struct hist_trigger_data *hist_data = data->private_data; 5993 struct event_trigger_data *test, *named_data = NULL; 5994 bool match = false; 5995 5996 lockdep_assert_held(&event_mutex); 5997 5998 if (hist_data->attrs->name) 5999 named_data = find_named_trigger(hist_data->attrs->name); 6000 6001 list_for_each_entry(test, &file->triggers, list) { 6002 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6003 if (hist_trigger_match(data, test, named_data, false)) { 6004 match = true; 6005 break; 6006 } 6007 } 6008 } 6009 6010 return match; 6011 } 6012 6013 static bool hist_trigger_check_refs(struct event_trigger_data *data, 6014 struct trace_event_file *file) 6015 { 6016 struct hist_trigger_data *hist_data = data->private_data; 6017 struct event_trigger_data *test, *named_data = NULL; 6018 6019 lockdep_assert_held(&event_mutex); 6020 6021 if (hist_data->attrs->name) 6022 named_data = find_named_trigger(hist_data->attrs->name); 6023 6024 list_for_each_entry(test, &file->triggers, list) { 6025 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6026 if (!hist_trigger_match(data, test, named_data, false)) 6027 continue; 6028 hist_data = test->private_data; 6029 if (check_var_refs(hist_data)) 6030 return true; 6031 break; 6032 } 6033 } 6034 6035 return false; 6036 } 6037 6038 static void hist_unregister_trigger(char *glob, struct event_trigger_ops *ops, 6039 struct event_trigger_data *data, 6040 struct trace_event_file *file) 6041 { 6042 struct hist_trigger_data *hist_data = data->private_data; 6043 struct event_trigger_data *test, *named_data = NULL; 6044 bool unregistered = false; 6045 6046 lockdep_assert_held(&event_mutex); 6047 6048 if (hist_data->attrs->name) 6049 named_data = find_named_trigger(hist_data->attrs->name); 6050 6051 list_for_each_entry(test, &file->triggers, list) { 6052 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6053 if (!hist_trigger_match(data, test, named_data, false)) 6054 continue; 6055 unregistered = true; 6056 list_del_rcu(&test->list); 6057 trace_event_trigger_enable_disable(file, 0); 6058 update_cond_flag(file); 6059 break; 6060 } 6061 } 6062 6063 if (unregistered && test->ops->free) 6064 test->ops->free(test->ops, test); 6065 6066 if (hist_data->enable_timestamps) { 6067 if (!hist_data->remove || unregistered) 6068 tracing_set_filter_buffering(file->tr, false); 6069 } 6070 } 6071 6072 static bool hist_file_check_refs(struct trace_event_file *file) 6073 { 6074 struct hist_trigger_data *hist_data; 6075 struct event_trigger_data *test; 6076 6077 lockdep_assert_held(&event_mutex); 6078 6079 list_for_each_entry(test, &file->triggers, list) { 6080 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6081 hist_data = test->private_data; 6082 if (check_var_refs(hist_data)) 6083 return true; 6084 } 6085 } 6086 6087 return false; 6088 } 6089 6090 static void hist_unreg_all(struct trace_event_file *file) 6091 { 6092 struct event_trigger_data *test, *n; 6093 struct hist_trigger_data *hist_data; 6094 struct synth_event *se; 6095 const char *se_name; 6096 6097 lockdep_assert_held(&event_mutex); 6098 6099 if (hist_file_check_refs(file)) 6100 return; 6101 6102 list_for_each_entry_safe(test, n, &file->triggers, list) { 6103 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6104 hist_data = test->private_data; 6105 list_del_rcu(&test->list); 6106 trace_event_trigger_enable_disable(file, 0); 6107 6108 se_name = trace_event_name(file->event_call); 6109 se = find_synth_event(se_name); 6110 if (se) 6111 se->ref--; 6112 6113 update_cond_flag(file); 6114 if (hist_data->enable_timestamps) 6115 tracing_set_filter_buffering(file->tr, false); 6116 if (test->ops->free) 6117 test->ops->free(test->ops, test); 6118 } 6119 } 6120 } 6121 6122 static int event_hist_trigger_func(struct event_command *cmd_ops, 6123 struct trace_event_file *file, 6124 char *glob, char *cmd, char *param) 6125 { 6126 unsigned int hist_trigger_bits = TRACING_MAP_BITS_DEFAULT; 6127 struct event_trigger_data *trigger_data; 6128 struct hist_trigger_attrs *attrs; 6129 struct event_trigger_ops *trigger_ops; 6130 struct hist_trigger_data *hist_data; 6131 struct synth_event *se; 6132 const char *se_name; 6133 bool remove = false; 6134 char *trigger, *p, *start; 6135 int ret = 0; 6136 6137 lockdep_assert_held(&event_mutex); 6138 6139 if (glob && strlen(glob)) { 6140 hist_err_clear(); 6141 last_cmd_set(file, param); 6142 } 6143 6144 if (!param) 6145 return -EINVAL; 6146 6147 if (glob[0] == '!') 6148 remove = true; 6149 6150 /* 6151 * separate the trigger from the filter (k:v [if filter]) 6152 * allowing for whitespace in the trigger 6153 */ 6154 p = trigger = param; 6155 do { 6156 p = strstr(p, "if"); 6157 if (!p) 6158 break; 6159 if (p == param) 6160 return -EINVAL; 6161 if (*(p - 1) != ' ' && *(p - 1) != '\t') { 6162 p++; 6163 continue; 6164 } 6165 if (p >= param + strlen(param) - (sizeof("if") - 1) - 1) 6166 return -EINVAL; 6167 if (*(p + sizeof("if") - 1) != ' ' && *(p + sizeof("if") - 1) != '\t') { 6168 p++; 6169 continue; 6170 } 6171 break; 6172 } while (p); 6173 6174 if (!p) 6175 param = NULL; 6176 else { 6177 *(p - 1) = '\0'; 6178 param = strstrip(p); 6179 trigger = strstrip(trigger); 6180 } 6181 6182 /* 6183 * To simplify arithmetic expression parsing, replace occurrences of 6184 * '.sym-offset' modifier with '.symXoffset' 6185 */ 6186 start = strstr(trigger, ".sym-offset"); 6187 while (start) { 6188 *(start + 4) = 'X'; 6189 start = strstr(start + 11, ".sym-offset"); 6190 } 6191 6192 attrs = parse_hist_trigger_attrs(file->tr, trigger); 6193 if (IS_ERR(attrs)) 6194 return PTR_ERR(attrs); 6195 6196 if (attrs->map_bits) 6197 hist_trigger_bits = attrs->map_bits; 6198 6199 hist_data = create_hist_data(hist_trigger_bits, attrs, file, remove); 6200 if (IS_ERR(hist_data)) { 6201 destroy_hist_trigger_attrs(attrs); 6202 return PTR_ERR(hist_data); 6203 } 6204 6205 trigger_ops = cmd_ops->get_trigger_ops(cmd, trigger); 6206 6207 trigger_data = kzalloc(sizeof(*trigger_data), GFP_KERNEL); 6208 if (!trigger_data) { 6209 ret = -ENOMEM; 6210 goto out_free; 6211 } 6212 6213 trigger_data->count = -1; 6214 trigger_data->ops = trigger_ops; 6215 trigger_data->cmd_ops = cmd_ops; 6216 6217 INIT_LIST_HEAD(&trigger_data->list); 6218 RCU_INIT_POINTER(trigger_data->filter, NULL); 6219 6220 trigger_data->private_data = hist_data; 6221 6222 /* if param is non-empty, it's supposed to be a filter */ 6223 if (param && cmd_ops->set_filter) { 6224 ret = cmd_ops->set_filter(param, trigger_data, file); 6225 if (ret < 0) 6226 goto out_free; 6227 } 6228 6229 if (remove) { 6230 if (!have_hist_trigger_match(trigger_data, file)) 6231 goto out_free; 6232 6233 if (hist_trigger_check_refs(trigger_data, file)) { 6234 ret = -EBUSY; 6235 goto out_free; 6236 } 6237 6238 cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file); 6239 se_name = trace_event_name(file->event_call); 6240 se = find_synth_event(se_name); 6241 if (se) 6242 se->ref--; 6243 ret = 0; 6244 goto out_free; 6245 } 6246 6247 ret = cmd_ops->reg(glob, trigger_ops, trigger_data, file); 6248 /* 6249 * The above returns on success the # of triggers registered, 6250 * but if it didn't register any it returns zero. Consider no 6251 * triggers registered a failure too. 6252 */ 6253 if (!ret) { 6254 if (!(attrs->pause || attrs->cont || attrs->clear)) 6255 ret = -ENOENT; 6256 goto out_free; 6257 } else if (ret < 0) 6258 goto out_free; 6259 6260 if (get_named_trigger_data(trigger_data)) 6261 goto enable; 6262 6263 if (has_hist_vars(hist_data)) 6264 save_hist_vars(hist_data); 6265 6266 ret = create_actions(hist_data); 6267 if (ret) 6268 goto out_unreg; 6269 6270 ret = tracing_map_init(hist_data->map); 6271 if (ret) 6272 goto out_unreg; 6273 enable: 6274 ret = hist_trigger_enable(trigger_data, file); 6275 if (ret) 6276 goto out_unreg; 6277 6278 se_name = trace_event_name(file->event_call); 6279 se = find_synth_event(se_name); 6280 if (se) 6281 se->ref++; 6282 /* Just return zero, not the number of registered triggers */ 6283 ret = 0; 6284 out: 6285 if (ret == 0) 6286 hist_err_clear(); 6287 6288 return ret; 6289 out_unreg: 6290 cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file); 6291 out_free: 6292 if (cmd_ops->set_filter) 6293 cmd_ops->set_filter(NULL, trigger_data, NULL); 6294 6295 remove_hist_vars(hist_data); 6296 6297 kfree(trigger_data); 6298 6299 destroy_hist_data(hist_data); 6300 goto out; 6301 } 6302 6303 static struct event_command trigger_hist_cmd = { 6304 .name = "hist", 6305 .trigger_type = ETT_EVENT_HIST, 6306 .flags = EVENT_CMD_FL_NEEDS_REC, 6307 .func = event_hist_trigger_func, 6308 .reg = hist_register_trigger, 6309 .unreg = hist_unregister_trigger, 6310 .unreg_all = hist_unreg_all, 6311 .get_trigger_ops = event_hist_get_trigger_ops, 6312 .set_filter = set_trigger_filter, 6313 }; 6314 6315 __init int register_trigger_hist_cmd(void) 6316 { 6317 int ret; 6318 6319 ret = register_event_command(&trigger_hist_cmd); 6320 WARN_ON(ret < 0); 6321 6322 return ret; 6323 } 6324 6325 static void 6326 hist_enable_trigger(struct event_trigger_data *data, 6327 struct trace_buffer *buffer, void *rec, 6328 struct ring_buffer_event *event) 6329 { 6330 struct enable_trigger_data *enable_data = data->private_data; 6331 struct event_trigger_data *test; 6332 6333 list_for_each_entry_rcu(test, &enable_data->file->triggers, list, 6334 lockdep_is_held(&event_mutex)) { 6335 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6336 if (enable_data->enable) 6337 test->paused = false; 6338 else 6339 test->paused = true; 6340 } 6341 } 6342 } 6343 6344 static void 6345 hist_enable_count_trigger(struct event_trigger_data *data, 6346 struct trace_buffer *buffer, void *rec, 6347 struct ring_buffer_event *event) 6348 { 6349 if (!data->count) 6350 return; 6351 6352 if (data->count != -1) 6353 (data->count)--; 6354 6355 hist_enable_trigger(data, buffer, rec, event); 6356 } 6357 6358 static struct event_trigger_ops hist_enable_trigger_ops = { 6359 .func = hist_enable_trigger, 6360 .print = event_enable_trigger_print, 6361 .init = event_trigger_init, 6362 .free = event_enable_trigger_free, 6363 }; 6364 6365 static struct event_trigger_ops hist_enable_count_trigger_ops = { 6366 .func = hist_enable_count_trigger, 6367 .print = event_enable_trigger_print, 6368 .init = event_trigger_init, 6369 .free = event_enable_trigger_free, 6370 }; 6371 6372 static struct event_trigger_ops hist_disable_trigger_ops = { 6373 .func = hist_enable_trigger, 6374 .print = event_enable_trigger_print, 6375 .init = event_trigger_init, 6376 .free = event_enable_trigger_free, 6377 }; 6378 6379 static struct event_trigger_ops hist_disable_count_trigger_ops = { 6380 .func = hist_enable_count_trigger, 6381 .print = event_enable_trigger_print, 6382 .init = event_trigger_init, 6383 .free = event_enable_trigger_free, 6384 }; 6385 6386 static struct event_trigger_ops * 6387 hist_enable_get_trigger_ops(char *cmd, char *param) 6388 { 6389 struct event_trigger_ops *ops; 6390 bool enable; 6391 6392 enable = (strcmp(cmd, ENABLE_HIST_STR) == 0); 6393 6394 if (enable) 6395 ops = param ? &hist_enable_count_trigger_ops : 6396 &hist_enable_trigger_ops; 6397 else 6398 ops = param ? &hist_disable_count_trigger_ops : 6399 &hist_disable_trigger_ops; 6400 6401 return ops; 6402 } 6403 6404 static void hist_enable_unreg_all(struct trace_event_file *file) 6405 { 6406 struct event_trigger_data *test, *n; 6407 6408 list_for_each_entry_safe(test, n, &file->triggers, list) { 6409 if (test->cmd_ops->trigger_type == ETT_HIST_ENABLE) { 6410 list_del_rcu(&test->list); 6411 update_cond_flag(file); 6412 trace_event_trigger_enable_disable(file, 0); 6413 if (test->ops->free) 6414 test->ops->free(test->ops, test); 6415 } 6416 } 6417 } 6418 6419 static struct event_command trigger_hist_enable_cmd = { 6420 .name = ENABLE_HIST_STR, 6421 .trigger_type = ETT_HIST_ENABLE, 6422 .func = event_enable_trigger_func, 6423 .reg = event_enable_register_trigger, 6424 .unreg = event_enable_unregister_trigger, 6425 .unreg_all = hist_enable_unreg_all, 6426 .get_trigger_ops = hist_enable_get_trigger_ops, 6427 .set_filter = set_trigger_filter, 6428 }; 6429 6430 static struct event_command trigger_hist_disable_cmd = { 6431 .name = DISABLE_HIST_STR, 6432 .trigger_type = ETT_HIST_ENABLE, 6433 .func = event_enable_trigger_func, 6434 .reg = event_enable_register_trigger, 6435 .unreg = event_enable_unregister_trigger, 6436 .unreg_all = hist_enable_unreg_all, 6437 .get_trigger_ops = hist_enable_get_trigger_ops, 6438 .set_filter = set_trigger_filter, 6439 }; 6440 6441 static __init void unregister_trigger_hist_enable_disable_cmds(void) 6442 { 6443 unregister_event_command(&trigger_hist_enable_cmd); 6444 unregister_event_command(&trigger_hist_disable_cmd); 6445 } 6446 6447 __init int register_trigger_hist_enable_disable_cmds(void) 6448 { 6449 int ret; 6450 6451 ret = register_event_command(&trigger_hist_enable_cmd); 6452 if (WARN_ON(ret < 0)) 6453 return ret; 6454 ret = register_event_command(&trigger_hist_disable_cmd); 6455 if (WARN_ON(ret < 0)) 6456 unregister_trigger_hist_enable_disable_cmds(); 6457 6458 return ret; 6459 } 6460