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_reldynstring(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 u32 *item = event + hist_field->field->offset; 227 u32 str_item = *item; 228 int str_loc = str_item & 0xffff; 229 char *addr = (char *)&item[1] + str_loc; 230 231 return (u64)(unsigned long)addr; 232 } 233 234 static u64 hist_field_pstring(struct hist_field *hist_field, 235 struct tracing_map_elt *elt, 236 struct trace_buffer *buffer, 237 struct ring_buffer_event *rbe, 238 void *event) 239 { 240 char **addr = (char **)(event + hist_field->field->offset); 241 242 return (u64)(unsigned long)*addr; 243 } 244 245 static u64 hist_field_log2(struct hist_field *hist_field, 246 struct tracing_map_elt *elt, 247 struct trace_buffer *buffer, 248 struct ring_buffer_event *rbe, 249 void *event) 250 { 251 struct hist_field *operand = hist_field->operands[0]; 252 253 u64 val = operand->fn(operand, elt, buffer, rbe, event); 254 255 return (u64) ilog2(roundup_pow_of_two(val)); 256 } 257 258 static u64 hist_field_bucket(struct hist_field *hist_field, 259 struct tracing_map_elt *elt, 260 struct trace_buffer *buffer, 261 struct ring_buffer_event *rbe, 262 void *event) 263 { 264 struct hist_field *operand = hist_field->operands[0]; 265 unsigned long buckets = hist_field->buckets; 266 267 u64 val = operand->fn(operand, elt, buffer, rbe, event); 268 269 if (WARN_ON_ONCE(!buckets)) 270 return val; 271 272 if (val >= LONG_MAX) 273 val = div64_ul(val, buckets); 274 else 275 val = (u64)((unsigned long)val / buckets); 276 return val * buckets; 277 } 278 279 static u64 hist_field_plus(struct hist_field *hist_field, 280 struct tracing_map_elt *elt, 281 struct trace_buffer *buffer, 282 struct ring_buffer_event *rbe, 283 void *event) 284 { 285 struct hist_field *operand1 = hist_field->operands[0]; 286 struct hist_field *operand2 = hist_field->operands[1]; 287 288 u64 val1 = operand1->fn(operand1, elt, buffer, rbe, event); 289 u64 val2 = operand2->fn(operand2, elt, buffer, rbe, event); 290 291 return val1 + val2; 292 } 293 294 static u64 hist_field_minus(struct hist_field *hist_field, 295 struct tracing_map_elt *elt, 296 struct trace_buffer *buffer, 297 struct ring_buffer_event *rbe, 298 void *event) 299 { 300 struct hist_field *operand1 = hist_field->operands[0]; 301 struct hist_field *operand2 = hist_field->operands[1]; 302 303 u64 val1 = operand1->fn(operand1, elt, buffer, rbe, event); 304 u64 val2 = operand2->fn(operand2, elt, buffer, rbe, event); 305 306 return val1 - val2; 307 } 308 309 static u64 hist_field_div(struct hist_field *hist_field, 310 struct tracing_map_elt *elt, 311 struct trace_buffer *buffer, 312 struct ring_buffer_event *rbe, 313 void *event) 314 { 315 struct hist_field *operand1 = hist_field->operands[0]; 316 struct hist_field *operand2 = hist_field->operands[1]; 317 318 u64 val1 = operand1->fn(operand1, elt, buffer, rbe, event); 319 u64 val2 = operand2->fn(operand2, elt, buffer, rbe, event); 320 321 /* Return -1 for the undefined case */ 322 if (!val2) 323 return -1; 324 325 /* Use shift if the divisor is a power of 2 */ 326 if (!(val2 & (val2 - 1))) 327 return val1 >> __ffs64(val2); 328 329 return div64_u64(val1, val2); 330 } 331 332 static u64 div_by_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 val1 >> __ffs64(operand2->constant); 344 } 345 346 static u64 div_by_not_power_of_two(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 return div64_u64(val1, operand2->constant); 358 } 359 360 static u64 div_by_mult_and_shift(struct hist_field *hist_field, 361 struct tracing_map_elt *elt, 362 struct trace_buffer *buffer, 363 struct ring_buffer_event *rbe, 364 void *event) 365 { 366 struct hist_field *operand1 = hist_field->operands[0]; 367 struct hist_field *operand2 = hist_field->operands[1]; 368 369 u64 val1 = operand1->fn(operand1, elt, buffer, rbe, event); 370 371 /* 372 * If the divisor is a constant, do a multiplication and shift instead. 373 * 374 * Choose Z = some power of 2. If Y <= Z, then: 375 * X / Y = (X * (Z / Y)) / Z 376 * 377 * (Z / Y) is a constant (mult) which is calculated at parse time, so: 378 * X / Y = (X * mult) / Z 379 * 380 * The division by Z can be replaced by a shift since Z is a power of 2: 381 * X / Y = (X * mult) >> HIST_DIV_SHIFT 382 * 383 * As long, as X < Z the results will not be off by more than 1. 384 */ 385 if (val1 < (1 << HIST_DIV_SHIFT)) { 386 u64 mult = operand2->div_multiplier; 387 388 return (val1 * mult + ((1 << HIST_DIV_SHIFT) - 1)) >> HIST_DIV_SHIFT; 389 } 390 391 return div64_u64(val1, operand2->constant); 392 } 393 394 static u64 hist_field_mult(struct hist_field *hist_field, 395 struct tracing_map_elt *elt, 396 struct trace_buffer *buffer, 397 struct ring_buffer_event *rbe, 398 void *event) 399 { 400 struct hist_field *operand1 = hist_field->operands[0]; 401 struct hist_field *operand2 = hist_field->operands[1]; 402 403 u64 val1 = operand1->fn(operand1, elt, buffer, rbe, event); 404 u64 val2 = operand2->fn(operand2, elt, buffer, rbe, event); 405 406 return val1 * val2; 407 } 408 409 static u64 hist_field_unary_minus(struct hist_field *hist_field, 410 struct tracing_map_elt *elt, 411 struct trace_buffer *buffer, 412 struct ring_buffer_event *rbe, 413 void *event) 414 { 415 struct hist_field *operand = hist_field->operands[0]; 416 417 s64 sval = (s64)operand->fn(operand, elt, buffer, rbe, event); 418 u64 val = (u64)-sval; 419 420 return val; 421 } 422 423 #define DEFINE_HIST_FIELD_FN(type) \ 424 static u64 hist_field_##type(struct hist_field *hist_field, \ 425 struct tracing_map_elt *elt, \ 426 struct trace_buffer *buffer, \ 427 struct ring_buffer_event *rbe, \ 428 void *event) \ 429 { \ 430 type *addr = (type *)(event + hist_field->field->offset); \ 431 \ 432 return (u64)(unsigned long)*addr; \ 433 } 434 435 DEFINE_HIST_FIELD_FN(s64); 436 DEFINE_HIST_FIELD_FN(u64); 437 DEFINE_HIST_FIELD_FN(s32); 438 DEFINE_HIST_FIELD_FN(u32); 439 DEFINE_HIST_FIELD_FN(s16); 440 DEFINE_HIST_FIELD_FN(u16); 441 DEFINE_HIST_FIELD_FN(s8); 442 DEFINE_HIST_FIELD_FN(u8); 443 444 #define for_each_hist_field(i, hist_data) \ 445 for ((i) = 0; (i) < (hist_data)->n_fields; (i)++) 446 447 #define for_each_hist_val_field(i, hist_data) \ 448 for ((i) = 0; (i) < (hist_data)->n_vals; (i)++) 449 450 #define for_each_hist_key_field(i, hist_data) \ 451 for ((i) = (hist_data)->n_vals; (i) < (hist_data)->n_fields; (i)++) 452 453 #define HIST_STACKTRACE_DEPTH 16 454 #define HIST_STACKTRACE_SIZE (HIST_STACKTRACE_DEPTH * sizeof(unsigned long)) 455 #define HIST_STACKTRACE_SKIP 5 456 457 #define HITCOUNT_IDX 0 458 #define HIST_KEY_SIZE_MAX (MAX_FILTER_STR_VAL + HIST_STACKTRACE_SIZE) 459 460 enum hist_field_flags { 461 HIST_FIELD_FL_HITCOUNT = 1 << 0, 462 HIST_FIELD_FL_KEY = 1 << 1, 463 HIST_FIELD_FL_STRING = 1 << 2, 464 HIST_FIELD_FL_HEX = 1 << 3, 465 HIST_FIELD_FL_SYM = 1 << 4, 466 HIST_FIELD_FL_SYM_OFFSET = 1 << 5, 467 HIST_FIELD_FL_EXECNAME = 1 << 6, 468 HIST_FIELD_FL_SYSCALL = 1 << 7, 469 HIST_FIELD_FL_STACKTRACE = 1 << 8, 470 HIST_FIELD_FL_LOG2 = 1 << 9, 471 HIST_FIELD_FL_TIMESTAMP = 1 << 10, 472 HIST_FIELD_FL_TIMESTAMP_USECS = 1 << 11, 473 HIST_FIELD_FL_VAR = 1 << 12, 474 HIST_FIELD_FL_EXPR = 1 << 13, 475 HIST_FIELD_FL_VAR_REF = 1 << 14, 476 HIST_FIELD_FL_CPU = 1 << 15, 477 HIST_FIELD_FL_ALIAS = 1 << 16, 478 HIST_FIELD_FL_BUCKET = 1 << 17, 479 HIST_FIELD_FL_CONST = 1 << 18, 480 }; 481 482 struct var_defs { 483 unsigned int n_vars; 484 char *name[TRACING_MAP_VARS_MAX]; 485 char *expr[TRACING_MAP_VARS_MAX]; 486 }; 487 488 struct hist_trigger_attrs { 489 char *keys_str; 490 char *vals_str; 491 char *sort_key_str; 492 char *name; 493 char *clock; 494 bool pause; 495 bool cont; 496 bool clear; 497 bool ts_in_usecs; 498 unsigned int map_bits; 499 500 char *assignment_str[TRACING_MAP_VARS_MAX]; 501 unsigned int n_assignments; 502 503 char *action_str[HIST_ACTIONS_MAX]; 504 unsigned int n_actions; 505 506 struct var_defs var_defs; 507 }; 508 509 struct field_var { 510 struct hist_field *var; 511 struct hist_field *val; 512 }; 513 514 struct field_var_hist { 515 struct hist_trigger_data *hist_data; 516 char *cmd; 517 }; 518 519 struct hist_trigger_data { 520 struct hist_field *fields[HIST_FIELDS_MAX]; 521 unsigned int n_vals; 522 unsigned int n_keys; 523 unsigned int n_fields; 524 unsigned int n_vars; 525 unsigned int n_var_str; 526 unsigned int key_size; 527 struct tracing_map_sort_key sort_keys[TRACING_MAP_SORT_KEYS_MAX]; 528 unsigned int n_sort_keys; 529 struct trace_event_file *event_file; 530 struct hist_trigger_attrs *attrs; 531 struct tracing_map *map; 532 bool enable_timestamps; 533 bool remove; 534 struct hist_field *var_refs[TRACING_MAP_VARS_MAX]; 535 unsigned int n_var_refs; 536 537 struct action_data *actions[HIST_ACTIONS_MAX]; 538 unsigned int n_actions; 539 540 struct field_var *field_vars[SYNTH_FIELDS_MAX]; 541 unsigned int n_field_vars; 542 unsigned int n_field_var_str; 543 struct field_var_hist *field_var_hists[SYNTH_FIELDS_MAX]; 544 unsigned int n_field_var_hists; 545 546 struct field_var *save_vars[SYNTH_FIELDS_MAX]; 547 unsigned int n_save_vars; 548 unsigned int n_save_var_str; 549 }; 550 551 struct action_data; 552 553 typedef void (*action_fn_t) (struct hist_trigger_data *hist_data, 554 struct tracing_map_elt *elt, 555 struct trace_buffer *buffer, void *rec, 556 struct ring_buffer_event *rbe, void *key, 557 struct action_data *data, u64 *var_ref_vals); 558 559 typedef bool (*check_track_val_fn_t) (u64 track_val, u64 var_val); 560 561 enum handler_id { 562 HANDLER_ONMATCH = 1, 563 HANDLER_ONMAX, 564 HANDLER_ONCHANGE, 565 }; 566 567 enum action_id { 568 ACTION_SAVE = 1, 569 ACTION_TRACE, 570 ACTION_SNAPSHOT, 571 }; 572 573 struct action_data { 574 enum handler_id handler; 575 enum action_id action; 576 char *action_name; 577 action_fn_t fn; 578 579 unsigned int n_params; 580 char *params[SYNTH_FIELDS_MAX]; 581 582 /* 583 * When a histogram trigger is hit, the values of any 584 * references to variables, including variables being passed 585 * as parameters to synthetic events, are collected into a 586 * var_ref_vals array. This var_ref_idx array is an array of 587 * indices into the var_ref_vals array, one for each synthetic 588 * event param, and is passed to the synthetic event 589 * invocation. 590 */ 591 unsigned int var_ref_idx[TRACING_MAP_VARS_MAX]; 592 struct synth_event *synth_event; 593 bool use_trace_keyword; 594 char *synth_event_name; 595 596 union { 597 struct { 598 char *event; 599 char *event_system; 600 } match_data; 601 602 struct { 603 /* 604 * var_str contains the $-unstripped variable 605 * name referenced by var_ref, and used when 606 * printing the action. Because var_ref 607 * creation is deferred to create_actions(), 608 * we need a per-action way to save it until 609 * then, thus var_str. 610 */ 611 char *var_str; 612 613 /* 614 * var_ref refers to the variable being 615 * tracked e.g onmax($var). 616 */ 617 struct hist_field *var_ref; 618 619 /* 620 * track_var contains the 'invisible' tracking 621 * variable created to keep the current 622 * e.g. max value. 623 */ 624 struct hist_field *track_var; 625 626 check_track_val_fn_t check_val; 627 action_fn_t save_data; 628 } track_data; 629 }; 630 }; 631 632 struct track_data { 633 u64 track_val; 634 bool updated; 635 636 unsigned int key_len; 637 void *key; 638 struct tracing_map_elt elt; 639 640 struct action_data *action_data; 641 struct hist_trigger_data *hist_data; 642 }; 643 644 struct hist_elt_data { 645 char *comm; 646 u64 *var_ref_vals; 647 char **field_var_str; 648 int n_field_var_str; 649 }; 650 651 struct snapshot_context { 652 struct tracing_map_elt *elt; 653 void *key; 654 }; 655 656 /* 657 * Returns the specific division function to use if the divisor 658 * is constant. This avoids extra branches when the trigger is hit. 659 */ 660 static hist_field_fn_t hist_field_get_div_fn(struct hist_field *divisor) 661 { 662 u64 div = divisor->constant; 663 664 if (!(div & (div - 1))) 665 return div_by_power_of_two; 666 667 /* If the divisor is too large, do a regular division */ 668 if (div > (1 << HIST_DIV_SHIFT)) 669 return div_by_not_power_of_two; 670 671 divisor->div_multiplier = div64_u64((u64)(1 << HIST_DIV_SHIFT), div); 672 return div_by_mult_and_shift; 673 } 674 675 static void track_data_free(struct track_data *track_data) 676 { 677 struct hist_elt_data *elt_data; 678 679 if (!track_data) 680 return; 681 682 kfree(track_data->key); 683 684 elt_data = track_data->elt.private_data; 685 if (elt_data) { 686 kfree(elt_data->comm); 687 kfree(elt_data); 688 } 689 690 kfree(track_data); 691 } 692 693 static struct track_data *track_data_alloc(unsigned int key_len, 694 struct action_data *action_data, 695 struct hist_trigger_data *hist_data) 696 { 697 struct track_data *data = kzalloc(sizeof(*data), GFP_KERNEL); 698 struct hist_elt_data *elt_data; 699 700 if (!data) 701 return ERR_PTR(-ENOMEM); 702 703 data->key = kzalloc(key_len, GFP_KERNEL); 704 if (!data->key) { 705 track_data_free(data); 706 return ERR_PTR(-ENOMEM); 707 } 708 709 data->key_len = key_len; 710 data->action_data = action_data; 711 data->hist_data = hist_data; 712 713 elt_data = kzalloc(sizeof(*elt_data), GFP_KERNEL); 714 if (!elt_data) { 715 track_data_free(data); 716 return ERR_PTR(-ENOMEM); 717 } 718 719 data->elt.private_data = elt_data; 720 721 elt_data->comm = kzalloc(TASK_COMM_LEN, GFP_KERNEL); 722 if (!elt_data->comm) { 723 track_data_free(data); 724 return ERR_PTR(-ENOMEM); 725 } 726 727 return data; 728 } 729 730 static char last_cmd[MAX_FILTER_STR_VAL]; 731 static char last_cmd_loc[MAX_FILTER_STR_VAL]; 732 733 static int errpos(char *str) 734 { 735 return err_pos(last_cmd, str); 736 } 737 738 static void last_cmd_set(struct trace_event_file *file, char *str) 739 { 740 const char *system = NULL, *name = NULL; 741 struct trace_event_call *call; 742 743 if (!str) 744 return; 745 746 strcpy(last_cmd, "hist:"); 747 strncat(last_cmd, str, MAX_FILTER_STR_VAL - 1 - sizeof("hist:")); 748 749 if (file) { 750 call = file->event_call; 751 system = call->class->system; 752 if (system) { 753 name = trace_event_name(call); 754 if (!name) 755 system = NULL; 756 } 757 } 758 759 if (system) 760 snprintf(last_cmd_loc, MAX_FILTER_STR_VAL, "hist:%s:%s", system, name); 761 } 762 763 static void hist_err(struct trace_array *tr, u8 err_type, u8 err_pos) 764 { 765 tracing_log_err(tr, last_cmd_loc, last_cmd, err_text, 766 err_type, err_pos); 767 } 768 769 static void hist_err_clear(void) 770 { 771 last_cmd[0] = '\0'; 772 last_cmd_loc[0] = '\0'; 773 } 774 775 typedef void (*synth_probe_func_t) (void *__data, u64 *var_ref_vals, 776 unsigned int *var_ref_idx); 777 778 static inline void trace_synth(struct synth_event *event, u64 *var_ref_vals, 779 unsigned int *var_ref_idx) 780 { 781 struct tracepoint *tp = event->tp; 782 783 if (unlikely(atomic_read(&tp->key.enabled) > 0)) { 784 struct tracepoint_func *probe_func_ptr; 785 synth_probe_func_t probe_func; 786 void *__data; 787 788 if (!(cpu_online(raw_smp_processor_id()))) 789 return; 790 791 probe_func_ptr = rcu_dereference_sched((tp)->funcs); 792 if (probe_func_ptr) { 793 do { 794 probe_func = probe_func_ptr->func; 795 __data = probe_func_ptr->data; 796 probe_func(__data, var_ref_vals, var_ref_idx); 797 } while ((++probe_func_ptr)->func); 798 } 799 } 800 } 801 802 static void action_trace(struct hist_trigger_data *hist_data, 803 struct tracing_map_elt *elt, 804 struct trace_buffer *buffer, void *rec, 805 struct ring_buffer_event *rbe, void *key, 806 struct action_data *data, u64 *var_ref_vals) 807 { 808 struct synth_event *event = data->synth_event; 809 810 trace_synth(event, var_ref_vals, data->var_ref_idx); 811 } 812 813 struct hist_var_data { 814 struct list_head list; 815 struct hist_trigger_data *hist_data; 816 }; 817 818 static u64 hist_field_timestamp(struct hist_field *hist_field, 819 struct tracing_map_elt *elt, 820 struct trace_buffer *buffer, 821 struct ring_buffer_event *rbe, 822 void *event) 823 { 824 struct hist_trigger_data *hist_data = hist_field->hist_data; 825 struct trace_array *tr = hist_data->event_file->tr; 826 827 u64 ts = ring_buffer_event_time_stamp(buffer, rbe); 828 829 if (hist_data->attrs->ts_in_usecs && trace_clock_in_ns(tr)) 830 ts = ns2usecs(ts); 831 832 return ts; 833 } 834 835 static u64 hist_field_cpu(struct hist_field *hist_field, 836 struct tracing_map_elt *elt, 837 struct trace_buffer *buffer, 838 struct ring_buffer_event *rbe, 839 void *event) 840 { 841 int cpu = smp_processor_id(); 842 843 return cpu; 844 } 845 846 /** 847 * check_field_for_var_ref - Check if a VAR_REF field references a variable 848 * @hist_field: The VAR_REF field to check 849 * @var_data: The hist trigger that owns the variable 850 * @var_idx: The trigger variable identifier 851 * 852 * Check the given VAR_REF field to see whether or not it references 853 * the given variable associated with the given trigger. 854 * 855 * Return: The VAR_REF field if it does reference the variable, NULL if not 856 */ 857 static struct hist_field * 858 check_field_for_var_ref(struct hist_field *hist_field, 859 struct hist_trigger_data *var_data, 860 unsigned int var_idx) 861 { 862 WARN_ON(!(hist_field && hist_field->flags & HIST_FIELD_FL_VAR_REF)); 863 864 if (hist_field && hist_field->var.idx == var_idx && 865 hist_field->var.hist_data == var_data) 866 return hist_field; 867 868 return NULL; 869 } 870 871 /** 872 * find_var_ref - Check if a trigger has a reference to a trigger variable 873 * @hist_data: The hist trigger that might have a reference to the variable 874 * @var_data: The hist trigger that owns the variable 875 * @var_idx: The trigger variable identifier 876 * 877 * Check the list of var_refs[] on the first hist trigger to see 878 * whether any of them are references to the variable on the second 879 * trigger. 880 * 881 * Return: The VAR_REF field referencing the variable if so, NULL if not 882 */ 883 static struct hist_field *find_var_ref(struct hist_trigger_data *hist_data, 884 struct hist_trigger_data *var_data, 885 unsigned int var_idx) 886 { 887 struct hist_field *hist_field; 888 unsigned int i; 889 890 for (i = 0; i < hist_data->n_var_refs; i++) { 891 hist_field = hist_data->var_refs[i]; 892 if (check_field_for_var_ref(hist_field, var_data, var_idx)) 893 return hist_field; 894 } 895 896 return NULL; 897 } 898 899 /** 900 * find_any_var_ref - Check if there is a reference to a given trigger variable 901 * @hist_data: The hist trigger 902 * @var_idx: The trigger variable identifier 903 * 904 * Check to see whether the given variable is currently referenced by 905 * any other trigger. 906 * 907 * The trigger the variable is defined on is explicitly excluded - the 908 * assumption being that a self-reference doesn't prevent a trigger 909 * from being removed. 910 * 911 * Return: The VAR_REF field referencing the variable if so, NULL if not 912 */ 913 static struct hist_field *find_any_var_ref(struct hist_trigger_data *hist_data, 914 unsigned int var_idx) 915 { 916 struct trace_array *tr = hist_data->event_file->tr; 917 struct hist_field *found = NULL; 918 struct hist_var_data *var_data; 919 920 list_for_each_entry(var_data, &tr->hist_vars, list) { 921 if (var_data->hist_data == hist_data) 922 continue; 923 found = find_var_ref(var_data->hist_data, hist_data, var_idx); 924 if (found) 925 break; 926 } 927 928 return found; 929 } 930 931 /** 932 * check_var_refs - Check if there is a reference to any of trigger's variables 933 * @hist_data: The hist trigger 934 * 935 * A trigger can define one or more variables. If any one of them is 936 * currently referenced by any other trigger, this function will 937 * determine that. 938 939 * Typically used to determine whether or not a trigger can be removed 940 * - if there are any references to a trigger's variables, it cannot. 941 * 942 * Return: True if there is a reference to any of trigger's variables 943 */ 944 static bool check_var_refs(struct hist_trigger_data *hist_data) 945 { 946 struct hist_field *field; 947 bool found = false; 948 int i; 949 950 for_each_hist_field(i, hist_data) { 951 field = hist_data->fields[i]; 952 if (field && field->flags & HIST_FIELD_FL_VAR) { 953 if (find_any_var_ref(hist_data, field->var.idx)) { 954 found = true; 955 break; 956 } 957 } 958 } 959 960 return found; 961 } 962 963 static struct hist_var_data *find_hist_vars(struct hist_trigger_data *hist_data) 964 { 965 struct trace_array *tr = hist_data->event_file->tr; 966 struct hist_var_data *var_data, *found = NULL; 967 968 list_for_each_entry(var_data, &tr->hist_vars, list) { 969 if (var_data->hist_data == hist_data) { 970 found = var_data; 971 break; 972 } 973 } 974 975 return found; 976 } 977 978 static bool field_has_hist_vars(struct hist_field *hist_field, 979 unsigned int level) 980 { 981 int i; 982 983 if (level > 3) 984 return false; 985 986 if (!hist_field) 987 return false; 988 989 if (hist_field->flags & HIST_FIELD_FL_VAR || 990 hist_field->flags & HIST_FIELD_FL_VAR_REF) 991 return true; 992 993 for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++) { 994 struct hist_field *operand; 995 996 operand = hist_field->operands[i]; 997 if (field_has_hist_vars(operand, level + 1)) 998 return true; 999 } 1000 1001 return false; 1002 } 1003 1004 static bool has_hist_vars(struct hist_trigger_data *hist_data) 1005 { 1006 struct hist_field *hist_field; 1007 int i; 1008 1009 for_each_hist_field(i, hist_data) { 1010 hist_field = hist_data->fields[i]; 1011 if (field_has_hist_vars(hist_field, 0)) 1012 return true; 1013 } 1014 1015 return false; 1016 } 1017 1018 static int save_hist_vars(struct hist_trigger_data *hist_data) 1019 { 1020 struct trace_array *tr = hist_data->event_file->tr; 1021 struct hist_var_data *var_data; 1022 1023 var_data = find_hist_vars(hist_data); 1024 if (var_data) 1025 return 0; 1026 1027 if (tracing_check_open_get_tr(tr)) 1028 return -ENODEV; 1029 1030 var_data = kzalloc(sizeof(*var_data), GFP_KERNEL); 1031 if (!var_data) { 1032 trace_array_put(tr); 1033 return -ENOMEM; 1034 } 1035 1036 var_data->hist_data = hist_data; 1037 list_add(&var_data->list, &tr->hist_vars); 1038 1039 return 0; 1040 } 1041 1042 static void remove_hist_vars(struct hist_trigger_data *hist_data) 1043 { 1044 struct trace_array *tr = hist_data->event_file->tr; 1045 struct hist_var_data *var_data; 1046 1047 var_data = find_hist_vars(hist_data); 1048 if (!var_data) 1049 return; 1050 1051 if (WARN_ON(check_var_refs(hist_data))) 1052 return; 1053 1054 list_del(&var_data->list); 1055 1056 kfree(var_data); 1057 1058 trace_array_put(tr); 1059 } 1060 1061 static struct hist_field *find_var_field(struct hist_trigger_data *hist_data, 1062 const char *var_name) 1063 { 1064 struct hist_field *hist_field, *found = NULL; 1065 int i; 1066 1067 for_each_hist_field(i, hist_data) { 1068 hist_field = hist_data->fields[i]; 1069 if (hist_field && hist_field->flags & HIST_FIELD_FL_VAR && 1070 strcmp(hist_field->var.name, var_name) == 0) { 1071 found = hist_field; 1072 break; 1073 } 1074 } 1075 1076 return found; 1077 } 1078 1079 static struct hist_field *find_var(struct hist_trigger_data *hist_data, 1080 struct trace_event_file *file, 1081 const char *var_name) 1082 { 1083 struct hist_trigger_data *test_data; 1084 struct event_trigger_data *test; 1085 struct hist_field *hist_field; 1086 1087 lockdep_assert_held(&event_mutex); 1088 1089 hist_field = find_var_field(hist_data, var_name); 1090 if (hist_field) 1091 return hist_field; 1092 1093 list_for_each_entry(test, &file->triggers, list) { 1094 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 1095 test_data = test->private_data; 1096 hist_field = find_var_field(test_data, var_name); 1097 if (hist_field) 1098 return hist_field; 1099 } 1100 } 1101 1102 return NULL; 1103 } 1104 1105 static struct trace_event_file *find_var_file(struct trace_array *tr, 1106 char *system, 1107 char *event_name, 1108 char *var_name) 1109 { 1110 struct hist_trigger_data *var_hist_data; 1111 struct hist_var_data *var_data; 1112 struct trace_event_file *file, *found = NULL; 1113 1114 if (system) 1115 return find_event_file(tr, system, event_name); 1116 1117 list_for_each_entry(var_data, &tr->hist_vars, list) { 1118 var_hist_data = var_data->hist_data; 1119 file = var_hist_data->event_file; 1120 if (file == found) 1121 continue; 1122 1123 if (find_var_field(var_hist_data, var_name)) { 1124 if (found) { 1125 hist_err(tr, HIST_ERR_VAR_NOT_UNIQUE, errpos(var_name)); 1126 return NULL; 1127 } 1128 1129 found = file; 1130 } 1131 } 1132 1133 return found; 1134 } 1135 1136 static struct hist_field *find_file_var(struct trace_event_file *file, 1137 const char *var_name) 1138 { 1139 struct hist_trigger_data *test_data; 1140 struct event_trigger_data *test; 1141 struct hist_field *hist_field; 1142 1143 lockdep_assert_held(&event_mutex); 1144 1145 list_for_each_entry(test, &file->triggers, list) { 1146 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 1147 test_data = test->private_data; 1148 hist_field = find_var_field(test_data, var_name); 1149 if (hist_field) 1150 return hist_field; 1151 } 1152 } 1153 1154 return NULL; 1155 } 1156 1157 static struct hist_field * 1158 find_match_var(struct hist_trigger_data *hist_data, char *var_name) 1159 { 1160 struct trace_array *tr = hist_data->event_file->tr; 1161 struct hist_field *hist_field, *found = NULL; 1162 struct trace_event_file *file; 1163 unsigned int i; 1164 1165 for (i = 0; i < hist_data->n_actions; i++) { 1166 struct action_data *data = hist_data->actions[i]; 1167 1168 if (data->handler == HANDLER_ONMATCH) { 1169 char *system = data->match_data.event_system; 1170 char *event_name = data->match_data.event; 1171 1172 file = find_var_file(tr, system, event_name, var_name); 1173 if (!file) 1174 continue; 1175 hist_field = find_file_var(file, var_name); 1176 if (hist_field) { 1177 if (found) { 1178 hist_err(tr, HIST_ERR_VAR_NOT_UNIQUE, 1179 errpos(var_name)); 1180 return ERR_PTR(-EINVAL); 1181 } 1182 1183 found = hist_field; 1184 } 1185 } 1186 } 1187 return found; 1188 } 1189 1190 static struct hist_field *find_event_var(struct hist_trigger_data *hist_data, 1191 char *system, 1192 char *event_name, 1193 char *var_name) 1194 { 1195 struct trace_array *tr = hist_data->event_file->tr; 1196 struct hist_field *hist_field = NULL; 1197 struct trace_event_file *file; 1198 1199 if (!system || !event_name) { 1200 hist_field = find_match_var(hist_data, var_name); 1201 if (IS_ERR(hist_field)) 1202 return NULL; 1203 if (hist_field) 1204 return hist_field; 1205 } 1206 1207 file = find_var_file(tr, system, event_name, var_name); 1208 if (!file) 1209 return NULL; 1210 1211 hist_field = find_file_var(file, var_name); 1212 1213 return hist_field; 1214 } 1215 1216 static u64 hist_field_var_ref(struct hist_field *hist_field, 1217 struct tracing_map_elt *elt, 1218 struct trace_buffer *buffer, 1219 struct ring_buffer_event *rbe, 1220 void *event) 1221 { 1222 struct hist_elt_data *elt_data; 1223 u64 var_val = 0; 1224 1225 if (WARN_ON_ONCE(!elt)) 1226 return var_val; 1227 1228 elt_data = elt->private_data; 1229 var_val = elt_data->var_ref_vals[hist_field->var_ref_idx]; 1230 1231 return var_val; 1232 } 1233 1234 static bool resolve_var_refs(struct hist_trigger_data *hist_data, void *key, 1235 u64 *var_ref_vals, bool self) 1236 { 1237 struct hist_trigger_data *var_data; 1238 struct tracing_map_elt *var_elt; 1239 struct hist_field *hist_field; 1240 unsigned int i, var_idx; 1241 bool resolved = true; 1242 u64 var_val = 0; 1243 1244 for (i = 0; i < hist_data->n_var_refs; i++) { 1245 hist_field = hist_data->var_refs[i]; 1246 var_idx = hist_field->var.idx; 1247 var_data = hist_field->var.hist_data; 1248 1249 if (var_data == NULL) { 1250 resolved = false; 1251 break; 1252 } 1253 1254 if ((self && var_data != hist_data) || 1255 (!self && var_data == hist_data)) 1256 continue; 1257 1258 var_elt = tracing_map_lookup(var_data->map, key); 1259 if (!var_elt) { 1260 resolved = false; 1261 break; 1262 } 1263 1264 if (!tracing_map_var_set(var_elt, var_idx)) { 1265 resolved = false; 1266 break; 1267 } 1268 1269 if (self || !hist_field->read_once) 1270 var_val = tracing_map_read_var(var_elt, var_idx); 1271 else 1272 var_val = tracing_map_read_var_once(var_elt, var_idx); 1273 1274 var_ref_vals[i] = var_val; 1275 } 1276 1277 return resolved; 1278 } 1279 1280 static const char *hist_field_name(struct hist_field *field, 1281 unsigned int level) 1282 { 1283 const char *field_name = ""; 1284 1285 if (level > 1) 1286 return field_name; 1287 1288 if (field->field) 1289 field_name = field->field->name; 1290 else if (field->flags & HIST_FIELD_FL_LOG2 || 1291 field->flags & HIST_FIELD_FL_ALIAS || 1292 field->flags & HIST_FIELD_FL_BUCKET) 1293 field_name = hist_field_name(field->operands[0], ++level); 1294 else if (field->flags & HIST_FIELD_FL_CPU) 1295 field_name = "common_cpu"; 1296 else if (field->flags & HIST_FIELD_FL_EXPR || 1297 field->flags & HIST_FIELD_FL_VAR_REF) { 1298 if (field->system) { 1299 static char full_name[MAX_FILTER_STR_VAL]; 1300 1301 strcat(full_name, field->system); 1302 strcat(full_name, "."); 1303 strcat(full_name, field->event_name); 1304 strcat(full_name, "."); 1305 strcat(full_name, field->name); 1306 field_name = full_name; 1307 } else 1308 field_name = field->name; 1309 } else if (field->flags & HIST_FIELD_FL_TIMESTAMP) 1310 field_name = "common_timestamp"; 1311 1312 if (field_name == NULL) 1313 field_name = ""; 1314 1315 return field_name; 1316 } 1317 1318 static hist_field_fn_t select_value_fn(int field_size, int field_is_signed) 1319 { 1320 hist_field_fn_t fn = NULL; 1321 1322 switch (field_size) { 1323 case 8: 1324 if (field_is_signed) 1325 fn = hist_field_s64; 1326 else 1327 fn = hist_field_u64; 1328 break; 1329 case 4: 1330 if (field_is_signed) 1331 fn = hist_field_s32; 1332 else 1333 fn = hist_field_u32; 1334 break; 1335 case 2: 1336 if (field_is_signed) 1337 fn = hist_field_s16; 1338 else 1339 fn = hist_field_u16; 1340 break; 1341 case 1: 1342 if (field_is_signed) 1343 fn = hist_field_s8; 1344 else 1345 fn = hist_field_u8; 1346 break; 1347 } 1348 1349 return fn; 1350 } 1351 1352 static int parse_map_size(char *str) 1353 { 1354 unsigned long size, map_bits; 1355 int ret; 1356 1357 ret = kstrtoul(str, 0, &size); 1358 if (ret) 1359 goto out; 1360 1361 map_bits = ilog2(roundup_pow_of_two(size)); 1362 if (map_bits < TRACING_MAP_BITS_MIN || 1363 map_bits > TRACING_MAP_BITS_MAX) 1364 ret = -EINVAL; 1365 else 1366 ret = map_bits; 1367 out: 1368 return ret; 1369 } 1370 1371 static void destroy_hist_trigger_attrs(struct hist_trigger_attrs *attrs) 1372 { 1373 unsigned int i; 1374 1375 if (!attrs) 1376 return; 1377 1378 for (i = 0; i < attrs->n_assignments; i++) 1379 kfree(attrs->assignment_str[i]); 1380 1381 for (i = 0; i < attrs->n_actions; i++) 1382 kfree(attrs->action_str[i]); 1383 1384 kfree(attrs->name); 1385 kfree(attrs->sort_key_str); 1386 kfree(attrs->keys_str); 1387 kfree(attrs->vals_str); 1388 kfree(attrs->clock); 1389 kfree(attrs); 1390 } 1391 1392 static int parse_action(char *str, struct hist_trigger_attrs *attrs) 1393 { 1394 int ret = -EINVAL; 1395 1396 if (attrs->n_actions >= HIST_ACTIONS_MAX) 1397 return ret; 1398 1399 if ((str_has_prefix(str, "onmatch(")) || 1400 (str_has_prefix(str, "onmax(")) || 1401 (str_has_prefix(str, "onchange("))) { 1402 attrs->action_str[attrs->n_actions] = kstrdup(str, GFP_KERNEL); 1403 if (!attrs->action_str[attrs->n_actions]) { 1404 ret = -ENOMEM; 1405 return ret; 1406 } 1407 attrs->n_actions++; 1408 ret = 0; 1409 } 1410 return ret; 1411 } 1412 1413 static int parse_assignment(struct trace_array *tr, 1414 char *str, struct hist_trigger_attrs *attrs) 1415 { 1416 int len, ret = 0; 1417 1418 if ((len = str_has_prefix(str, "key=")) || 1419 (len = str_has_prefix(str, "keys="))) { 1420 attrs->keys_str = kstrdup(str + len, GFP_KERNEL); 1421 if (!attrs->keys_str) { 1422 ret = -ENOMEM; 1423 goto out; 1424 } 1425 } else if ((len = str_has_prefix(str, "val=")) || 1426 (len = str_has_prefix(str, "vals=")) || 1427 (len = str_has_prefix(str, "values="))) { 1428 attrs->vals_str = kstrdup(str + len, GFP_KERNEL); 1429 if (!attrs->vals_str) { 1430 ret = -ENOMEM; 1431 goto out; 1432 } 1433 } else if ((len = str_has_prefix(str, "sort="))) { 1434 attrs->sort_key_str = kstrdup(str + len, GFP_KERNEL); 1435 if (!attrs->sort_key_str) { 1436 ret = -ENOMEM; 1437 goto out; 1438 } 1439 } else if (str_has_prefix(str, "name=")) { 1440 attrs->name = kstrdup(str, GFP_KERNEL); 1441 if (!attrs->name) { 1442 ret = -ENOMEM; 1443 goto out; 1444 } 1445 } else if ((len = str_has_prefix(str, "clock="))) { 1446 str += len; 1447 1448 str = strstrip(str); 1449 attrs->clock = kstrdup(str, GFP_KERNEL); 1450 if (!attrs->clock) { 1451 ret = -ENOMEM; 1452 goto out; 1453 } 1454 } else if ((len = str_has_prefix(str, "size="))) { 1455 int map_bits = parse_map_size(str + len); 1456 1457 if (map_bits < 0) { 1458 ret = map_bits; 1459 goto out; 1460 } 1461 attrs->map_bits = map_bits; 1462 } else { 1463 char *assignment; 1464 1465 if (attrs->n_assignments == TRACING_MAP_VARS_MAX) { 1466 hist_err(tr, HIST_ERR_TOO_MANY_VARS, errpos(str)); 1467 ret = -EINVAL; 1468 goto out; 1469 } 1470 1471 assignment = kstrdup(str, GFP_KERNEL); 1472 if (!assignment) { 1473 ret = -ENOMEM; 1474 goto out; 1475 } 1476 1477 attrs->assignment_str[attrs->n_assignments++] = assignment; 1478 } 1479 out: 1480 return ret; 1481 } 1482 1483 static struct hist_trigger_attrs * 1484 parse_hist_trigger_attrs(struct trace_array *tr, char *trigger_str) 1485 { 1486 struct hist_trigger_attrs *attrs; 1487 int ret = 0; 1488 1489 attrs = kzalloc(sizeof(*attrs), GFP_KERNEL); 1490 if (!attrs) 1491 return ERR_PTR(-ENOMEM); 1492 1493 while (trigger_str) { 1494 char *str = strsep(&trigger_str, ":"); 1495 char *rhs; 1496 1497 rhs = strchr(str, '='); 1498 if (rhs) { 1499 if (!strlen(++rhs)) { 1500 ret = -EINVAL; 1501 hist_err(tr, HIST_ERR_EMPTY_ASSIGNMENT, errpos(str)); 1502 goto free; 1503 } 1504 ret = parse_assignment(tr, str, attrs); 1505 if (ret) 1506 goto free; 1507 } else if (strcmp(str, "pause") == 0) 1508 attrs->pause = true; 1509 else if ((strcmp(str, "cont") == 0) || 1510 (strcmp(str, "continue") == 0)) 1511 attrs->cont = true; 1512 else if (strcmp(str, "clear") == 0) 1513 attrs->clear = true; 1514 else { 1515 ret = parse_action(str, attrs); 1516 if (ret) 1517 goto free; 1518 } 1519 } 1520 1521 if (!attrs->keys_str) { 1522 ret = -EINVAL; 1523 goto free; 1524 } 1525 1526 if (!attrs->clock) { 1527 attrs->clock = kstrdup("global", GFP_KERNEL); 1528 if (!attrs->clock) { 1529 ret = -ENOMEM; 1530 goto free; 1531 } 1532 } 1533 1534 return attrs; 1535 free: 1536 destroy_hist_trigger_attrs(attrs); 1537 1538 return ERR_PTR(ret); 1539 } 1540 1541 static inline void save_comm(char *comm, struct task_struct *task) 1542 { 1543 if (!task->pid) { 1544 strcpy(comm, "<idle>"); 1545 return; 1546 } 1547 1548 if (WARN_ON_ONCE(task->pid < 0)) { 1549 strcpy(comm, "<XXX>"); 1550 return; 1551 } 1552 1553 strncpy(comm, task->comm, TASK_COMM_LEN); 1554 } 1555 1556 static void hist_elt_data_free(struct hist_elt_data *elt_data) 1557 { 1558 unsigned int i; 1559 1560 for (i = 0; i < elt_data->n_field_var_str; i++) 1561 kfree(elt_data->field_var_str[i]); 1562 1563 kfree(elt_data->field_var_str); 1564 1565 kfree(elt_data->comm); 1566 kfree(elt_data); 1567 } 1568 1569 static void hist_trigger_elt_data_free(struct tracing_map_elt *elt) 1570 { 1571 struct hist_elt_data *elt_data = elt->private_data; 1572 1573 hist_elt_data_free(elt_data); 1574 } 1575 1576 static int hist_trigger_elt_data_alloc(struct tracing_map_elt *elt) 1577 { 1578 struct hist_trigger_data *hist_data = elt->map->private_data; 1579 unsigned int size = TASK_COMM_LEN; 1580 struct hist_elt_data *elt_data; 1581 struct hist_field *hist_field; 1582 unsigned int i, n_str; 1583 1584 elt_data = kzalloc(sizeof(*elt_data), GFP_KERNEL); 1585 if (!elt_data) 1586 return -ENOMEM; 1587 1588 for_each_hist_field(i, hist_data) { 1589 hist_field = hist_data->fields[i]; 1590 1591 if (hist_field->flags & HIST_FIELD_FL_EXECNAME) { 1592 elt_data->comm = kzalloc(size, GFP_KERNEL); 1593 if (!elt_data->comm) { 1594 kfree(elt_data); 1595 return -ENOMEM; 1596 } 1597 break; 1598 } 1599 } 1600 1601 n_str = hist_data->n_field_var_str + hist_data->n_save_var_str + 1602 hist_data->n_var_str; 1603 if (n_str > SYNTH_FIELDS_MAX) { 1604 hist_elt_data_free(elt_data); 1605 return -EINVAL; 1606 } 1607 1608 BUILD_BUG_ON(STR_VAR_LEN_MAX & (sizeof(u64) - 1)); 1609 1610 size = STR_VAR_LEN_MAX; 1611 1612 elt_data->field_var_str = kcalloc(n_str, sizeof(char *), GFP_KERNEL); 1613 if (!elt_data->field_var_str) { 1614 hist_elt_data_free(elt_data); 1615 return -EINVAL; 1616 } 1617 elt_data->n_field_var_str = n_str; 1618 1619 for (i = 0; i < n_str; i++) { 1620 elt_data->field_var_str[i] = kzalloc(size, GFP_KERNEL); 1621 if (!elt_data->field_var_str[i]) { 1622 hist_elt_data_free(elt_data); 1623 return -ENOMEM; 1624 } 1625 } 1626 1627 elt->private_data = elt_data; 1628 1629 return 0; 1630 } 1631 1632 static void hist_trigger_elt_data_init(struct tracing_map_elt *elt) 1633 { 1634 struct hist_elt_data *elt_data = elt->private_data; 1635 1636 if (elt_data->comm) 1637 save_comm(elt_data->comm, current); 1638 } 1639 1640 static const struct tracing_map_ops hist_trigger_elt_data_ops = { 1641 .elt_alloc = hist_trigger_elt_data_alloc, 1642 .elt_free = hist_trigger_elt_data_free, 1643 .elt_init = hist_trigger_elt_data_init, 1644 }; 1645 1646 static const char *get_hist_field_flags(struct hist_field *hist_field) 1647 { 1648 const char *flags_str = NULL; 1649 1650 if (hist_field->flags & HIST_FIELD_FL_HEX) 1651 flags_str = "hex"; 1652 else if (hist_field->flags & HIST_FIELD_FL_SYM) 1653 flags_str = "sym"; 1654 else if (hist_field->flags & HIST_FIELD_FL_SYM_OFFSET) 1655 flags_str = "sym-offset"; 1656 else if (hist_field->flags & HIST_FIELD_FL_EXECNAME) 1657 flags_str = "execname"; 1658 else if (hist_field->flags & HIST_FIELD_FL_SYSCALL) 1659 flags_str = "syscall"; 1660 else if (hist_field->flags & HIST_FIELD_FL_LOG2) 1661 flags_str = "log2"; 1662 else if (hist_field->flags & HIST_FIELD_FL_BUCKET) 1663 flags_str = "buckets"; 1664 else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP_USECS) 1665 flags_str = "usecs"; 1666 1667 return flags_str; 1668 } 1669 1670 static void expr_field_str(struct hist_field *field, char *expr) 1671 { 1672 if (field->flags & HIST_FIELD_FL_VAR_REF) 1673 strcat(expr, "$"); 1674 else if (field->flags & HIST_FIELD_FL_CONST) { 1675 char str[HIST_CONST_DIGITS_MAX]; 1676 1677 snprintf(str, HIST_CONST_DIGITS_MAX, "%llu", field->constant); 1678 strcat(expr, str); 1679 } 1680 1681 strcat(expr, hist_field_name(field, 0)); 1682 1683 if (field->flags && !(field->flags & HIST_FIELD_FL_VAR_REF)) { 1684 const char *flags_str = get_hist_field_flags(field); 1685 1686 if (flags_str) { 1687 strcat(expr, "."); 1688 strcat(expr, flags_str); 1689 } 1690 } 1691 } 1692 1693 static char *expr_str(struct hist_field *field, unsigned int level) 1694 { 1695 char *expr; 1696 1697 if (level > 1) 1698 return NULL; 1699 1700 expr = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL); 1701 if (!expr) 1702 return NULL; 1703 1704 if (!field->operands[0]) { 1705 expr_field_str(field, expr); 1706 return expr; 1707 } 1708 1709 if (field->operator == FIELD_OP_UNARY_MINUS) { 1710 char *subexpr; 1711 1712 strcat(expr, "-("); 1713 subexpr = expr_str(field->operands[0], ++level); 1714 if (!subexpr) { 1715 kfree(expr); 1716 return NULL; 1717 } 1718 strcat(expr, subexpr); 1719 strcat(expr, ")"); 1720 1721 kfree(subexpr); 1722 1723 return expr; 1724 } 1725 1726 expr_field_str(field->operands[0], expr); 1727 1728 switch (field->operator) { 1729 case FIELD_OP_MINUS: 1730 strcat(expr, "-"); 1731 break; 1732 case FIELD_OP_PLUS: 1733 strcat(expr, "+"); 1734 break; 1735 case FIELD_OP_DIV: 1736 strcat(expr, "/"); 1737 break; 1738 case FIELD_OP_MULT: 1739 strcat(expr, "*"); 1740 break; 1741 default: 1742 kfree(expr); 1743 return NULL; 1744 } 1745 1746 expr_field_str(field->operands[1], expr); 1747 1748 return expr; 1749 } 1750 1751 /* 1752 * If field_op != FIELD_OP_NONE, *sep points to the root operator 1753 * of the expression tree to be evaluated. 1754 */ 1755 static int contains_operator(char *str, char **sep) 1756 { 1757 enum field_op_id field_op = FIELD_OP_NONE; 1758 char *minus_op, *plus_op, *div_op, *mult_op; 1759 1760 1761 /* 1762 * Report the last occurrence of the operators first, so that the 1763 * expression is evaluated left to right. This is important since 1764 * subtraction and division are not associative. 1765 * 1766 * e.g 1767 * 64/8/4/2 is 1, i.e 64/8/4/2 = ((64/8)/4)/2 1768 * 14-7-5-2 is 0, i.e 14-7-5-2 = ((14-7)-5)-2 1769 */ 1770 1771 /* 1772 * First, find lower precedence addition and subtraction 1773 * since the expression will be evaluated recursively. 1774 */ 1775 minus_op = strrchr(str, '-'); 1776 if (minus_op) { 1777 /* 1778 * Unary minus is not supported in sub-expressions. If 1779 * present, it is always the next root operator. 1780 */ 1781 if (minus_op == str) { 1782 field_op = FIELD_OP_UNARY_MINUS; 1783 goto out; 1784 } 1785 1786 field_op = FIELD_OP_MINUS; 1787 } 1788 1789 plus_op = strrchr(str, '+'); 1790 if (plus_op || minus_op) { 1791 /* 1792 * For operators of the same precedence use to rightmost as the 1793 * root, so that the expression is evaluated left to right. 1794 */ 1795 if (plus_op > minus_op) 1796 field_op = FIELD_OP_PLUS; 1797 goto out; 1798 } 1799 1800 /* 1801 * Multiplication and division have higher precedence than addition and 1802 * subtraction. 1803 */ 1804 div_op = strrchr(str, '/'); 1805 if (div_op) 1806 field_op = FIELD_OP_DIV; 1807 1808 mult_op = strrchr(str, '*'); 1809 /* 1810 * For operators of the same precedence use to rightmost as the 1811 * root, so that the expression is evaluated left to right. 1812 */ 1813 if (mult_op > div_op) 1814 field_op = FIELD_OP_MULT; 1815 1816 out: 1817 if (sep) { 1818 switch (field_op) { 1819 case FIELD_OP_UNARY_MINUS: 1820 case FIELD_OP_MINUS: 1821 *sep = minus_op; 1822 break; 1823 case FIELD_OP_PLUS: 1824 *sep = plus_op; 1825 break; 1826 case FIELD_OP_DIV: 1827 *sep = div_op; 1828 break; 1829 case FIELD_OP_MULT: 1830 *sep = mult_op; 1831 break; 1832 case FIELD_OP_NONE: 1833 default: 1834 *sep = NULL; 1835 break; 1836 } 1837 } 1838 1839 return field_op; 1840 } 1841 1842 static void get_hist_field(struct hist_field *hist_field) 1843 { 1844 hist_field->ref++; 1845 } 1846 1847 static void __destroy_hist_field(struct hist_field *hist_field) 1848 { 1849 if (--hist_field->ref > 1) 1850 return; 1851 1852 kfree(hist_field->var.name); 1853 kfree(hist_field->name); 1854 1855 /* Can likely be a const */ 1856 kfree_const(hist_field->type); 1857 1858 kfree(hist_field->system); 1859 kfree(hist_field->event_name); 1860 1861 kfree(hist_field); 1862 } 1863 1864 static void destroy_hist_field(struct hist_field *hist_field, 1865 unsigned int level) 1866 { 1867 unsigned int i; 1868 1869 if (level > 3) 1870 return; 1871 1872 if (!hist_field) 1873 return; 1874 1875 if (hist_field->flags & HIST_FIELD_FL_VAR_REF) 1876 return; /* var refs will be destroyed separately */ 1877 1878 for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++) 1879 destroy_hist_field(hist_field->operands[i], level + 1); 1880 1881 __destroy_hist_field(hist_field); 1882 } 1883 1884 static struct hist_field *create_hist_field(struct hist_trigger_data *hist_data, 1885 struct ftrace_event_field *field, 1886 unsigned long flags, 1887 char *var_name) 1888 { 1889 struct hist_field *hist_field; 1890 1891 if (field && is_function_field(field)) 1892 return NULL; 1893 1894 hist_field = kzalloc(sizeof(struct hist_field), GFP_KERNEL); 1895 if (!hist_field) 1896 return NULL; 1897 1898 hist_field->ref = 1; 1899 1900 hist_field->hist_data = hist_data; 1901 1902 if (flags & HIST_FIELD_FL_EXPR || flags & HIST_FIELD_FL_ALIAS) 1903 goto out; /* caller will populate */ 1904 1905 if (flags & HIST_FIELD_FL_VAR_REF) { 1906 hist_field->fn = hist_field_var_ref; 1907 goto out; 1908 } 1909 1910 if (flags & HIST_FIELD_FL_HITCOUNT) { 1911 hist_field->fn = hist_field_counter; 1912 hist_field->size = sizeof(u64); 1913 hist_field->type = "u64"; 1914 goto out; 1915 } 1916 1917 if (flags & HIST_FIELD_FL_CONST) { 1918 hist_field->fn = hist_field_const; 1919 hist_field->size = sizeof(u64); 1920 hist_field->type = kstrdup("u64", GFP_KERNEL); 1921 if (!hist_field->type) 1922 goto free; 1923 goto out; 1924 } 1925 1926 if (flags & HIST_FIELD_FL_STACKTRACE) { 1927 hist_field->fn = hist_field_none; 1928 goto out; 1929 } 1930 1931 if (flags & (HIST_FIELD_FL_LOG2 | HIST_FIELD_FL_BUCKET)) { 1932 unsigned long fl = flags & ~(HIST_FIELD_FL_LOG2 | HIST_FIELD_FL_BUCKET); 1933 hist_field->fn = flags & HIST_FIELD_FL_LOG2 ? hist_field_log2 : 1934 hist_field_bucket; 1935 hist_field->operands[0] = create_hist_field(hist_data, field, fl, NULL); 1936 hist_field->size = hist_field->operands[0]->size; 1937 hist_field->type = kstrdup_const(hist_field->operands[0]->type, GFP_KERNEL); 1938 if (!hist_field->type) 1939 goto free; 1940 goto out; 1941 } 1942 1943 if (flags & HIST_FIELD_FL_TIMESTAMP) { 1944 hist_field->fn = hist_field_timestamp; 1945 hist_field->size = sizeof(u64); 1946 hist_field->type = "u64"; 1947 goto out; 1948 } 1949 1950 if (flags & HIST_FIELD_FL_CPU) { 1951 hist_field->fn = hist_field_cpu; 1952 hist_field->size = sizeof(int); 1953 hist_field->type = "unsigned int"; 1954 goto out; 1955 } 1956 1957 if (WARN_ON_ONCE(!field)) 1958 goto out; 1959 1960 /* Pointers to strings are just pointers and dangerous to dereference */ 1961 if (is_string_field(field) && 1962 (field->filter_type != FILTER_PTR_STRING)) { 1963 flags |= HIST_FIELD_FL_STRING; 1964 1965 hist_field->size = MAX_FILTER_STR_VAL; 1966 hist_field->type = kstrdup_const(field->type, GFP_KERNEL); 1967 if (!hist_field->type) 1968 goto free; 1969 1970 if (field->filter_type == FILTER_STATIC_STRING) { 1971 hist_field->fn = hist_field_string; 1972 hist_field->size = field->size; 1973 } else if (field->filter_type == FILTER_DYN_STRING) { 1974 hist_field->fn = hist_field_dynstring; 1975 } else if (field->filter_type == FILTER_RDYN_STRING) 1976 hist_field->fn = hist_field_reldynstring; 1977 else 1978 hist_field->fn = hist_field_pstring; 1979 } else { 1980 hist_field->size = field->size; 1981 hist_field->is_signed = field->is_signed; 1982 hist_field->type = kstrdup_const(field->type, GFP_KERNEL); 1983 if (!hist_field->type) 1984 goto free; 1985 1986 hist_field->fn = select_value_fn(field->size, 1987 field->is_signed); 1988 if (!hist_field->fn) { 1989 destroy_hist_field(hist_field, 0); 1990 return NULL; 1991 } 1992 } 1993 out: 1994 hist_field->field = field; 1995 hist_field->flags = flags; 1996 1997 if (var_name) { 1998 hist_field->var.name = kstrdup(var_name, GFP_KERNEL); 1999 if (!hist_field->var.name) 2000 goto free; 2001 } 2002 2003 return hist_field; 2004 free: 2005 destroy_hist_field(hist_field, 0); 2006 return NULL; 2007 } 2008 2009 static void destroy_hist_fields(struct hist_trigger_data *hist_data) 2010 { 2011 unsigned int i; 2012 2013 for (i = 0; i < HIST_FIELDS_MAX; i++) { 2014 if (hist_data->fields[i]) { 2015 destroy_hist_field(hist_data->fields[i], 0); 2016 hist_data->fields[i] = NULL; 2017 } 2018 } 2019 2020 for (i = 0; i < hist_data->n_var_refs; i++) { 2021 WARN_ON(!(hist_data->var_refs[i]->flags & HIST_FIELD_FL_VAR_REF)); 2022 __destroy_hist_field(hist_data->var_refs[i]); 2023 hist_data->var_refs[i] = NULL; 2024 } 2025 } 2026 2027 static int init_var_ref(struct hist_field *ref_field, 2028 struct hist_field *var_field, 2029 char *system, char *event_name) 2030 { 2031 int err = 0; 2032 2033 ref_field->var.idx = var_field->var.idx; 2034 ref_field->var.hist_data = var_field->hist_data; 2035 ref_field->size = var_field->size; 2036 ref_field->is_signed = var_field->is_signed; 2037 ref_field->flags |= var_field->flags & 2038 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS); 2039 2040 if (system) { 2041 ref_field->system = kstrdup(system, GFP_KERNEL); 2042 if (!ref_field->system) 2043 return -ENOMEM; 2044 } 2045 2046 if (event_name) { 2047 ref_field->event_name = kstrdup(event_name, GFP_KERNEL); 2048 if (!ref_field->event_name) { 2049 err = -ENOMEM; 2050 goto free; 2051 } 2052 } 2053 2054 if (var_field->var.name) { 2055 ref_field->name = kstrdup(var_field->var.name, GFP_KERNEL); 2056 if (!ref_field->name) { 2057 err = -ENOMEM; 2058 goto free; 2059 } 2060 } else if (var_field->name) { 2061 ref_field->name = kstrdup(var_field->name, GFP_KERNEL); 2062 if (!ref_field->name) { 2063 err = -ENOMEM; 2064 goto free; 2065 } 2066 } 2067 2068 ref_field->type = kstrdup_const(var_field->type, GFP_KERNEL); 2069 if (!ref_field->type) { 2070 err = -ENOMEM; 2071 goto free; 2072 } 2073 out: 2074 return err; 2075 free: 2076 kfree(ref_field->system); 2077 kfree(ref_field->event_name); 2078 kfree(ref_field->name); 2079 2080 goto out; 2081 } 2082 2083 static int find_var_ref_idx(struct hist_trigger_data *hist_data, 2084 struct hist_field *var_field) 2085 { 2086 struct hist_field *ref_field; 2087 int i; 2088 2089 for (i = 0; i < hist_data->n_var_refs; i++) { 2090 ref_field = hist_data->var_refs[i]; 2091 if (ref_field->var.idx == var_field->var.idx && 2092 ref_field->var.hist_data == var_field->hist_data) 2093 return i; 2094 } 2095 2096 return -ENOENT; 2097 } 2098 2099 /** 2100 * create_var_ref - Create a variable reference and attach it to trigger 2101 * @hist_data: The trigger that will be referencing the variable 2102 * @var_field: The VAR field to create a reference to 2103 * @system: The optional system string 2104 * @event_name: The optional event_name string 2105 * 2106 * Given a variable hist_field, create a VAR_REF hist_field that 2107 * represents a reference to it. 2108 * 2109 * This function also adds the reference to the trigger that 2110 * now references the variable. 2111 * 2112 * Return: The VAR_REF field if successful, NULL if not 2113 */ 2114 static struct hist_field *create_var_ref(struct hist_trigger_data *hist_data, 2115 struct hist_field *var_field, 2116 char *system, char *event_name) 2117 { 2118 unsigned long flags = HIST_FIELD_FL_VAR_REF; 2119 struct hist_field *ref_field; 2120 int i; 2121 2122 /* Check if the variable already exists */ 2123 for (i = 0; i < hist_data->n_var_refs; i++) { 2124 ref_field = hist_data->var_refs[i]; 2125 if (ref_field->var.idx == var_field->var.idx && 2126 ref_field->var.hist_data == var_field->hist_data) { 2127 get_hist_field(ref_field); 2128 return ref_field; 2129 } 2130 } 2131 2132 ref_field = create_hist_field(var_field->hist_data, NULL, flags, NULL); 2133 if (ref_field) { 2134 if (init_var_ref(ref_field, var_field, system, event_name)) { 2135 destroy_hist_field(ref_field, 0); 2136 return NULL; 2137 } 2138 2139 hist_data->var_refs[hist_data->n_var_refs] = ref_field; 2140 ref_field->var_ref_idx = hist_data->n_var_refs++; 2141 } 2142 2143 return ref_field; 2144 } 2145 2146 static bool is_var_ref(char *var_name) 2147 { 2148 if (!var_name || strlen(var_name) < 2 || var_name[0] != '$') 2149 return false; 2150 2151 return true; 2152 } 2153 2154 static char *field_name_from_var(struct hist_trigger_data *hist_data, 2155 char *var_name) 2156 { 2157 char *name, *field; 2158 unsigned int i; 2159 2160 for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) { 2161 name = hist_data->attrs->var_defs.name[i]; 2162 2163 if (strcmp(var_name, name) == 0) { 2164 field = hist_data->attrs->var_defs.expr[i]; 2165 if (contains_operator(field, NULL) || is_var_ref(field)) 2166 continue; 2167 return field; 2168 } 2169 } 2170 2171 return NULL; 2172 } 2173 2174 static char *local_field_var_ref(struct hist_trigger_data *hist_data, 2175 char *system, char *event_name, 2176 char *var_name) 2177 { 2178 struct trace_event_call *call; 2179 2180 if (system && event_name) { 2181 call = hist_data->event_file->event_call; 2182 2183 if (strcmp(system, call->class->system) != 0) 2184 return NULL; 2185 2186 if (strcmp(event_name, trace_event_name(call)) != 0) 2187 return NULL; 2188 } 2189 2190 if (!!system != !!event_name) 2191 return NULL; 2192 2193 if (!is_var_ref(var_name)) 2194 return NULL; 2195 2196 var_name++; 2197 2198 return field_name_from_var(hist_data, var_name); 2199 } 2200 2201 static struct hist_field *parse_var_ref(struct hist_trigger_data *hist_data, 2202 char *system, char *event_name, 2203 char *var_name) 2204 { 2205 struct hist_field *var_field = NULL, *ref_field = NULL; 2206 struct trace_array *tr = hist_data->event_file->tr; 2207 2208 if (!is_var_ref(var_name)) 2209 return NULL; 2210 2211 var_name++; 2212 2213 var_field = find_event_var(hist_data, system, event_name, var_name); 2214 if (var_field) 2215 ref_field = create_var_ref(hist_data, var_field, 2216 system, event_name); 2217 2218 if (!ref_field) 2219 hist_err(tr, HIST_ERR_VAR_NOT_FOUND, errpos(var_name)); 2220 2221 return ref_field; 2222 } 2223 2224 static struct ftrace_event_field * 2225 parse_field(struct hist_trigger_data *hist_data, struct trace_event_file *file, 2226 char *field_str, unsigned long *flags, unsigned long *buckets) 2227 { 2228 struct ftrace_event_field *field = NULL; 2229 char *field_name, *modifier, *str; 2230 struct trace_array *tr = file->tr; 2231 2232 modifier = str = kstrdup(field_str, GFP_KERNEL); 2233 if (!modifier) 2234 return ERR_PTR(-ENOMEM); 2235 2236 field_name = strsep(&modifier, "."); 2237 if (modifier) { 2238 if (strcmp(modifier, "hex") == 0) 2239 *flags |= HIST_FIELD_FL_HEX; 2240 else if (strcmp(modifier, "sym") == 0) 2241 *flags |= HIST_FIELD_FL_SYM; 2242 /* 2243 * 'sym-offset' occurrences in the trigger string are modified 2244 * to 'symXoffset' to simplify arithmetic expression parsing. 2245 */ 2246 else if (strcmp(modifier, "symXoffset") == 0) 2247 *flags |= HIST_FIELD_FL_SYM_OFFSET; 2248 else if ((strcmp(modifier, "execname") == 0) && 2249 (strcmp(field_name, "common_pid") == 0)) 2250 *flags |= HIST_FIELD_FL_EXECNAME; 2251 else if (strcmp(modifier, "syscall") == 0) 2252 *flags |= HIST_FIELD_FL_SYSCALL; 2253 else if (strcmp(modifier, "log2") == 0) 2254 *flags |= HIST_FIELD_FL_LOG2; 2255 else if (strcmp(modifier, "usecs") == 0) 2256 *flags |= HIST_FIELD_FL_TIMESTAMP_USECS; 2257 else if (strncmp(modifier, "bucket", 6) == 0) { 2258 int ret; 2259 2260 modifier += 6; 2261 2262 if (*modifier == 's') 2263 modifier++; 2264 if (*modifier != '=') 2265 goto error; 2266 modifier++; 2267 ret = kstrtoul(modifier, 0, buckets); 2268 if (ret || !(*buckets)) 2269 goto error; 2270 *flags |= HIST_FIELD_FL_BUCKET; 2271 } else { 2272 error: 2273 hist_err(tr, HIST_ERR_BAD_FIELD_MODIFIER, errpos(modifier)); 2274 field = ERR_PTR(-EINVAL); 2275 goto out; 2276 } 2277 } 2278 2279 if (strcmp(field_name, "common_timestamp") == 0) { 2280 *flags |= HIST_FIELD_FL_TIMESTAMP; 2281 hist_data->enable_timestamps = true; 2282 if (*flags & HIST_FIELD_FL_TIMESTAMP_USECS) 2283 hist_data->attrs->ts_in_usecs = true; 2284 } else if (strcmp(field_name, "common_cpu") == 0) 2285 *flags |= HIST_FIELD_FL_CPU; 2286 else { 2287 field = trace_find_event_field(file->event_call, field_name); 2288 if (!field || !field->size) { 2289 /* 2290 * For backward compatibility, if field_name 2291 * was "cpu", then we treat this the same as 2292 * common_cpu. 2293 */ 2294 if (strcmp(field_name, "cpu") == 0) { 2295 *flags |= HIST_FIELD_FL_CPU; 2296 } else { 2297 hist_err(tr, HIST_ERR_FIELD_NOT_FOUND, 2298 errpos(field_name)); 2299 field = ERR_PTR(-EINVAL); 2300 goto out; 2301 } 2302 } 2303 } 2304 out: 2305 kfree(str); 2306 2307 return field; 2308 } 2309 2310 static struct hist_field *create_alias(struct hist_trigger_data *hist_data, 2311 struct hist_field *var_ref, 2312 char *var_name) 2313 { 2314 struct hist_field *alias = NULL; 2315 unsigned long flags = HIST_FIELD_FL_ALIAS | HIST_FIELD_FL_VAR; 2316 2317 alias = create_hist_field(hist_data, NULL, flags, var_name); 2318 if (!alias) 2319 return NULL; 2320 2321 alias->fn = var_ref->fn; 2322 alias->operands[0] = var_ref; 2323 2324 if (init_var_ref(alias, var_ref, var_ref->system, var_ref->event_name)) { 2325 destroy_hist_field(alias, 0); 2326 return NULL; 2327 } 2328 2329 alias->var_ref_idx = var_ref->var_ref_idx; 2330 2331 return alias; 2332 } 2333 2334 static struct hist_field *parse_const(struct hist_trigger_data *hist_data, 2335 char *str, char *var_name, 2336 unsigned long *flags) 2337 { 2338 struct trace_array *tr = hist_data->event_file->tr; 2339 struct hist_field *field = NULL; 2340 u64 constant; 2341 2342 if (kstrtoull(str, 0, &constant)) { 2343 hist_err(tr, HIST_ERR_EXPECT_NUMBER, errpos(str)); 2344 return NULL; 2345 } 2346 2347 *flags |= HIST_FIELD_FL_CONST; 2348 field = create_hist_field(hist_data, NULL, *flags, var_name); 2349 if (!field) 2350 return NULL; 2351 2352 field->constant = constant; 2353 2354 return field; 2355 } 2356 2357 static struct hist_field *parse_atom(struct hist_trigger_data *hist_data, 2358 struct trace_event_file *file, char *str, 2359 unsigned long *flags, char *var_name) 2360 { 2361 char *s, *ref_system = NULL, *ref_event = NULL, *ref_var = str; 2362 struct ftrace_event_field *field = NULL; 2363 struct hist_field *hist_field = NULL; 2364 unsigned long buckets = 0; 2365 int ret = 0; 2366 2367 if (isdigit(str[0])) { 2368 hist_field = parse_const(hist_data, str, var_name, flags); 2369 if (!hist_field) { 2370 ret = -EINVAL; 2371 goto out; 2372 } 2373 return hist_field; 2374 } 2375 2376 s = strchr(str, '.'); 2377 if (s) { 2378 s = strchr(++s, '.'); 2379 if (s) { 2380 ref_system = strsep(&str, "."); 2381 if (!str) { 2382 ret = -EINVAL; 2383 goto out; 2384 } 2385 ref_event = strsep(&str, "."); 2386 if (!str) { 2387 ret = -EINVAL; 2388 goto out; 2389 } 2390 ref_var = str; 2391 } 2392 } 2393 2394 s = local_field_var_ref(hist_data, ref_system, ref_event, ref_var); 2395 if (!s) { 2396 hist_field = parse_var_ref(hist_data, ref_system, 2397 ref_event, ref_var); 2398 if (hist_field) { 2399 if (var_name) { 2400 hist_field = create_alias(hist_data, hist_field, var_name); 2401 if (!hist_field) { 2402 ret = -ENOMEM; 2403 goto out; 2404 } 2405 } 2406 return hist_field; 2407 } 2408 } else 2409 str = s; 2410 2411 field = parse_field(hist_data, file, str, flags, &buckets); 2412 if (IS_ERR(field)) { 2413 ret = PTR_ERR(field); 2414 goto out; 2415 } 2416 2417 hist_field = create_hist_field(hist_data, field, *flags, var_name); 2418 if (!hist_field) { 2419 ret = -ENOMEM; 2420 goto out; 2421 } 2422 hist_field->buckets = buckets; 2423 2424 return hist_field; 2425 out: 2426 return ERR_PTR(ret); 2427 } 2428 2429 static struct hist_field *parse_expr(struct hist_trigger_data *hist_data, 2430 struct trace_event_file *file, 2431 char *str, unsigned long flags, 2432 char *var_name, unsigned int *n_subexprs); 2433 2434 static struct hist_field *parse_unary(struct hist_trigger_data *hist_data, 2435 struct trace_event_file *file, 2436 char *str, unsigned long flags, 2437 char *var_name, unsigned int *n_subexprs) 2438 { 2439 struct hist_field *operand1, *expr = NULL; 2440 unsigned long operand_flags; 2441 int ret = 0; 2442 char *s; 2443 2444 /* Unary minus operator, increment n_subexprs */ 2445 ++*n_subexprs; 2446 2447 /* we support only -(xxx) i.e. explicit parens required */ 2448 2449 if (*n_subexprs > 3) { 2450 hist_err(file->tr, HIST_ERR_TOO_MANY_SUBEXPR, errpos(str)); 2451 ret = -EINVAL; 2452 goto free; 2453 } 2454 2455 str++; /* skip leading '-' */ 2456 2457 s = strchr(str, '('); 2458 if (s) 2459 str++; 2460 else { 2461 ret = -EINVAL; 2462 goto free; 2463 } 2464 2465 s = strrchr(str, ')'); 2466 if (s) { 2467 /* unary minus not supported in sub-expressions */ 2468 if (*(s+1) != '\0') { 2469 hist_err(file->tr, HIST_ERR_UNARY_MINUS_SUBEXPR, 2470 errpos(str)); 2471 ret = -EINVAL; 2472 goto free; 2473 } 2474 *s = '\0'; 2475 } 2476 else { 2477 ret = -EINVAL; /* no closing ')' */ 2478 goto free; 2479 } 2480 2481 flags |= HIST_FIELD_FL_EXPR; 2482 expr = create_hist_field(hist_data, NULL, flags, var_name); 2483 if (!expr) { 2484 ret = -ENOMEM; 2485 goto free; 2486 } 2487 2488 operand_flags = 0; 2489 operand1 = parse_expr(hist_data, file, str, operand_flags, NULL, n_subexprs); 2490 if (IS_ERR(operand1)) { 2491 ret = PTR_ERR(operand1); 2492 goto free; 2493 } 2494 if (operand1->flags & HIST_FIELD_FL_STRING) { 2495 /* String type can not be the operand of unary operator. */ 2496 hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(str)); 2497 destroy_hist_field(operand1, 0); 2498 ret = -EINVAL; 2499 goto free; 2500 } 2501 2502 expr->flags |= operand1->flags & 2503 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS); 2504 expr->fn = hist_field_unary_minus; 2505 expr->operands[0] = operand1; 2506 expr->size = operand1->size; 2507 expr->is_signed = operand1->is_signed; 2508 expr->operator = FIELD_OP_UNARY_MINUS; 2509 expr->name = expr_str(expr, 0); 2510 expr->type = kstrdup_const(operand1->type, GFP_KERNEL); 2511 if (!expr->type) { 2512 ret = -ENOMEM; 2513 goto free; 2514 } 2515 2516 return expr; 2517 free: 2518 destroy_hist_field(expr, 0); 2519 return ERR_PTR(ret); 2520 } 2521 2522 /* 2523 * If the operands are var refs, return pointers the 2524 * variable(s) referenced in var1 and var2, else NULL. 2525 */ 2526 static int check_expr_operands(struct trace_array *tr, 2527 struct hist_field *operand1, 2528 struct hist_field *operand2, 2529 struct hist_field **var1, 2530 struct hist_field **var2) 2531 { 2532 unsigned long operand1_flags = operand1->flags; 2533 unsigned long operand2_flags = operand2->flags; 2534 2535 if ((operand1_flags & HIST_FIELD_FL_VAR_REF) || 2536 (operand1_flags & HIST_FIELD_FL_ALIAS)) { 2537 struct hist_field *var; 2538 2539 var = find_var_field(operand1->var.hist_data, operand1->name); 2540 if (!var) 2541 return -EINVAL; 2542 operand1_flags = var->flags; 2543 *var1 = var; 2544 } 2545 2546 if ((operand2_flags & HIST_FIELD_FL_VAR_REF) || 2547 (operand2_flags & HIST_FIELD_FL_ALIAS)) { 2548 struct hist_field *var; 2549 2550 var = find_var_field(operand2->var.hist_data, operand2->name); 2551 if (!var) 2552 return -EINVAL; 2553 operand2_flags = var->flags; 2554 *var2 = var; 2555 } 2556 2557 if ((operand1_flags & HIST_FIELD_FL_TIMESTAMP_USECS) != 2558 (operand2_flags & HIST_FIELD_FL_TIMESTAMP_USECS)) { 2559 hist_err(tr, HIST_ERR_TIMESTAMP_MISMATCH, 0); 2560 return -EINVAL; 2561 } 2562 2563 return 0; 2564 } 2565 2566 static struct hist_field *parse_expr(struct hist_trigger_data *hist_data, 2567 struct trace_event_file *file, 2568 char *str, unsigned long flags, 2569 char *var_name, unsigned int *n_subexprs) 2570 { 2571 struct hist_field *operand1 = NULL, *operand2 = NULL, *expr = NULL; 2572 struct hist_field *var1 = NULL, *var2 = NULL; 2573 unsigned long operand_flags, operand2_flags; 2574 int field_op, ret = -EINVAL; 2575 char *sep, *operand1_str; 2576 hist_field_fn_t op_fn; 2577 bool combine_consts; 2578 2579 if (*n_subexprs > 3) { 2580 hist_err(file->tr, HIST_ERR_TOO_MANY_SUBEXPR, errpos(str)); 2581 return ERR_PTR(-EINVAL); 2582 } 2583 2584 field_op = contains_operator(str, &sep); 2585 2586 if (field_op == FIELD_OP_NONE) 2587 return parse_atom(hist_data, file, str, &flags, var_name); 2588 2589 if (field_op == FIELD_OP_UNARY_MINUS) 2590 return parse_unary(hist_data, file, str, flags, var_name, n_subexprs); 2591 2592 /* Binary operator found, increment n_subexprs */ 2593 ++*n_subexprs; 2594 2595 /* Split the expression string at the root operator */ 2596 if (!sep) 2597 return ERR_PTR(-EINVAL); 2598 2599 *sep = '\0'; 2600 operand1_str = str; 2601 str = sep+1; 2602 2603 /* Binary operator requires both operands */ 2604 if (*operand1_str == '\0' || *str == '\0') 2605 return ERR_PTR(-EINVAL); 2606 2607 operand_flags = 0; 2608 2609 /* LHS of string is an expression e.g. a+b in a+b+c */ 2610 operand1 = parse_expr(hist_data, file, operand1_str, operand_flags, NULL, n_subexprs); 2611 if (IS_ERR(operand1)) 2612 return ERR_CAST(operand1); 2613 2614 if (operand1->flags & HIST_FIELD_FL_STRING) { 2615 hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(operand1_str)); 2616 ret = -EINVAL; 2617 goto free_op1; 2618 } 2619 2620 /* RHS of string is another expression e.g. c in a+b+c */ 2621 operand_flags = 0; 2622 operand2 = parse_expr(hist_data, file, str, operand_flags, NULL, n_subexprs); 2623 if (IS_ERR(operand2)) { 2624 ret = PTR_ERR(operand2); 2625 goto free_op1; 2626 } 2627 if (operand2->flags & HIST_FIELD_FL_STRING) { 2628 hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(str)); 2629 ret = -EINVAL; 2630 goto free_operands; 2631 } 2632 2633 switch (field_op) { 2634 case FIELD_OP_MINUS: 2635 op_fn = hist_field_minus; 2636 break; 2637 case FIELD_OP_PLUS: 2638 op_fn = hist_field_plus; 2639 break; 2640 case FIELD_OP_DIV: 2641 op_fn = hist_field_div; 2642 break; 2643 case FIELD_OP_MULT: 2644 op_fn = hist_field_mult; 2645 break; 2646 default: 2647 ret = -EINVAL; 2648 goto free_operands; 2649 } 2650 2651 ret = check_expr_operands(file->tr, operand1, operand2, &var1, &var2); 2652 if (ret) 2653 goto free_operands; 2654 2655 operand_flags = var1 ? var1->flags : operand1->flags; 2656 operand2_flags = var2 ? var2->flags : operand2->flags; 2657 2658 /* 2659 * If both operands are constant, the expression can be 2660 * collapsed to a single constant. 2661 */ 2662 combine_consts = operand_flags & operand2_flags & HIST_FIELD_FL_CONST; 2663 2664 flags |= combine_consts ? HIST_FIELD_FL_CONST : HIST_FIELD_FL_EXPR; 2665 2666 flags |= operand1->flags & 2667 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS); 2668 2669 expr = create_hist_field(hist_data, NULL, flags, var_name); 2670 if (!expr) { 2671 ret = -ENOMEM; 2672 goto free_operands; 2673 } 2674 2675 operand1->read_once = true; 2676 operand2->read_once = true; 2677 2678 /* The operands are now owned and free'd by 'expr' */ 2679 expr->operands[0] = operand1; 2680 expr->operands[1] = operand2; 2681 2682 if (field_op == FIELD_OP_DIV && 2683 operand2_flags & HIST_FIELD_FL_CONST) { 2684 u64 divisor = var2 ? var2->constant : operand2->constant; 2685 2686 if (!divisor) { 2687 hist_err(file->tr, HIST_ERR_DIVISION_BY_ZERO, errpos(str)); 2688 ret = -EDOM; 2689 goto free_expr; 2690 } 2691 2692 /* 2693 * Copy the divisor here so we don't have to look it up 2694 * later if this is a var ref 2695 */ 2696 operand2->constant = divisor; 2697 op_fn = hist_field_get_div_fn(operand2); 2698 } 2699 2700 if (combine_consts) { 2701 if (var1) 2702 expr->operands[0] = var1; 2703 if (var2) 2704 expr->operands[1] = var2; 2705 2706 expr->constant = op_fn(expr, NULL, NULL, NULL, NULL); 2707 2708 expr->operands[0] = NULL; 2709 expr->operands[1] = NULL; 2710 2711 /* 2712 * var refs won't be destroyed immediately 2713 * See: destroy_hist_field() 2714 */ 2715 destroy_hist_field(operand2, 0); 2716 destroy_hist_field(operand1, 0); 2717 2718 expr->name = expr_str(expr, 0); 2719 } else { 2720 expr->fn = op_fn; 2721 2722 /* The operand sizes should be the same, so just pick one */ 2723 expr->size = operand1->size; 2724 expr->is_signed = operand1->is_signed; 2725 2726 expr->operator = field_op; 2727 expr->type = kstrdup_const(operand1->type, GFP_KERNEL); 2728 if (!expr->type) { 2729 ret = -ENOMEM; 2730 goto free_expr; 2731 } 2732 2733 expr->name = expr_str(expr, 0); 2734 } 2735 2736 return expr; 2737 2738 free_operands: 2739 destroy_hist_field(operand2, 0); 2740 free_op1: 2741 destroy_hist_field(operand1, 0); 2742 return ERR_PTR(ret); 2743 2744 free_expr: 2745 destroy_hist_field(expr, 0); 2746 return ERR_PTR(ret); 2747 } 2748 2749 static char *find_trigger_filter(struct hist_trigger_data *hist_data, 2750 struct trace_event_file *file) 2751 { 2752 struct event_trigger_data *test; 2753 2754 lockdep_assert_held(&event_mutex); 2755 2756 list_for_each_entry(test, &file->triggers, list) { 2757 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 2758 if (test->private_data == hist_data) 2759 return test->filter_str; 2760 } 2761 } 2762 2763 return NULL; 2764 } 2765 2766 static struct event_command trigger_hist_cmd; 2767 static int event_hist_trigger_parse(struct event_command *cmd_ops, 2768 struct trace_event_file *file, 2769 char *glob, char *cmd, char *param); 2770 2771 static bool compatible_keys(struct hist_trigger_data *target_hist_data, 2772 struct hist_trigger_data *hist_data, 2773 unsigned int n_keys) 2774 { 2775 struct hist_field *target_hist_field, *hist_field; 2776 unsigned int n, i, j; 2777 2778 if (hist_data->n_fields - hist_data->n_vals != n_keys) 2779 return false; 2780 2781 i = hist_data->n_vals; 2782 j = target_hist_data->n_vals; 2783 2784 for (n = 0; n < n_keys; n++) { 2785 hist_field = hist_data->fields[i + n]; 2786 target_hist_field = target_hist_data->fields[j + n]; 2787 2788 if (strcmp(hist_field->type, target_hist_field->type) != 0) 2789 return false; 2790 if (hist_field->size != target_hist_field->size) 2791 return false; 2792 if (hist_field->is_signed != target_hist_field->is_signed) 2793 return false; 2794 } 2795 2796 return true; 2797 } 2798 2799 static struct hist_trigger_data * 2800 find_compatible_hist(struct hist_trigger_data *target_hist_data, 2801 struct trace_event_file *file) 2802 { 2803 struct hist_trigger_data *hist_data; 2804 struct event_trigger_data *test; 2805 unsigned int n_keys; 2806 2807 lockdep_assert_held(&event_mutex); 2808 2809 n_keys = target_hist_data->n_fields - target_hist_data->n_vals; 2810 2811 list_for_each_entry(test, &file->triggers, list) { 2812 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 2813 hist_data = test->private_data; 2814 2815 if (compatible_keys(target_hist_data, hist_data, n_keys)) 2816 return hist_data; 2817 } 2818 } 2819 2820 return NULL; 2821 } 2822 2823 static struct trace_event_file *event_file(struct trace_array *tr, 2824 char *system, char *event_name) 2825 { 2826 struct trace_event_file *file; 2827 2828 file = __find_event_file(tr, system, event_name); 2829 if (!file) 2830 return ERR_PTR(-EINVAL); 2831 2832 return file; 2833 } 2834 2835 static struct hist_field * 2836 find_synthetic_field_var(struct hist_trigger_data *target_hist_data, 2837 char *system, char *event_name, char *field_name) 2838 { 2839 struct hist_field *event_var; 2840 char *synthetic_name; 2841 2842 synthetic_name = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL); 2843 if (!synthetic_name) 2844 return ERR_PTR(-ENOMEM); 2845 2846 strcpy(synthetic_name, "synthetic_"); 2847 strcat(synthetic_name, field_name); 2848 2849 event_var = find_event_var(target_hist_data, system, event_name, synthetic_name); 2850 2851 kfree(synthetic_name); 2852 2853 return event_var; 2854 } 2855 2856 /** 2857 * create_field_var_hist - Automatically create a histogram and var for a field 2858 * @target_hist_data: The target hist trigger 2859 * @subsys_name: Optional subsystem name 2860 * @event_name: Optional event name 2861 * @field_name: The name of the field (and the resulting variable) 2862 * 2863 * Hist trigger actions fetch data from variables, not directly from 2864 * events. However, for convenience, users are allowed to directly 2865 * specify an event field in an action, which will be automatically 2866 * converted into a variable on their behalf. 2867 * 2868 * If a user specifies a field on an event that isn't the event the 2869 * histogram currently being defined (the target event histogram), the 2870 * only way that can be accomplished is if a new hist trigger is 2871 * created and the field variable defined on that. 2872 * 2873 * This function creates a new histogram compatible with the target 2874 * event (meaning a histogram with the same key as the target 2875 * histogram), and creates a variable for the specified field, but 2876 * with 'synthetic_' prepended to the variable name in order to avoid 2877 * collision with normal field variables. 2878 * 2879 * Return: The variable created for the field. 2880 */ 2881 static struct hist_field * 2882 create_field_var_hist(struct hist_trigger_data *target_hist_data, 2883 char *subsys_name, char *event_name, char *field_name) 2884 { 2885 struct trace_array *tr = target_hist_data->event_file->tr; 2886 struct hist_trigger_data *hist_data; 2887 unsigned int i, n, first = true; 2888 struct field_var_hist *var_hist; 2889 struct trace_event_file *file; 2890 struct hist_field *key_field; 2891 struct hist_field *event_var; 2892 char *saved_filter; 2893 char *cmd; 2894 int ret; 2895 2896 if (target_hist_data->n_field_var_hists >= SYNTH_FIELDS_MAX) { 2897 hist_err(tr, HIST_ERR_TOO_MANY_FIELD_VARS, errpos(field_name)); 2898 return ERR_PTR(-EINVAL); 2899 } 2900 2901 file = event_file(tr, subsys_name, event_name); 2902 2903 if (IS_ERR(file)) { 2904 hist_err(tr, HIST_ERR_EVENT_FILE_NOT_FOUND, errpos(field_name)); 2905 ret = PTR_ERR(file); 2906 return ERR_PTR(ret); 2907 } 2908 2909 /* 2910 * Look for a histogram compatible with target. We'll use the 2911 * found histogram specification to create a new matching 2912 * histogram with our variable on it. target_hist_data is not 2913 * yet a registered histogram so we can't use that. 2914 */ 2915 hist_data = find_compatible_hist(target_hist_data, file); 2916 if (!hist_data) { 2917 hist_err(tr, HIST_ERR_HIST_NOT_FOUND, errpos(field_name)); 2918 return ERR_PTR(-EINVAL); 2919 } 2920 2921 /* See if a synthetic field variable has already been created */ 2922 event_var = find_synthetic_field_var(target_hist_data, subsys_name, 2923 event_name, field_name); 2924 if (!IS_ERR_OR_NULL(event_var)) 2925 return event_var; 2926 2927 var_hist = kzalloc(sizeof(*var_hist), GFP_KERNEL); 2928 if (!var_hist) 2929 return ERR_PTR(-ENOMEM); 2930 2931 cmd = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL); 2932 if (!cmd) { 2933 kfree(var_hist); 2934 return ERR_PTR(-ENOMEM); 2935 } 2936 2937 /* Use the same keys as the compatible histogram */ 2938 strcat(cmd, "keys="); 2939 2940 for_each_hist_key_field(i, hist_data) { 2941 key_field = hist_data->fields[i]; 2942 if (!first) 2943 strcat(cmd, ","); 2944 strcat(cmd, key_field->field->name); 2945 first = false; 2946 } 2947 2948 /* Create the synthetic field variable specification */ 2949 strcat(cmd, ":synthetic_"); 2950 strcat(cmd, field_name); 2951 strcat(cmd, "="); 2952 strcat(cmd, field_name); 2953 2954 /* Use the same filter as the compatible histogram */ 2955 saved_filter = find_trigger_filter(hist_data, file); 2956 if (saved_filter) { 2957 strcat(cmd, " if "); 2958 strcat(cmd, saved_filter); 2959 } 2960 2961 var_hist->cmd = kstrdup(cmd, GFP_KERNEL); 2962 if (!var_hist->cmd) { 2963 kfree(cmd); 2964 kfree(var_hist); 2965 return ERR_PTR(-ENOMEM); 2966 } 2967 2968 /* Save the compatible histogram information */ 2969 var_hist->hist_data = hist_data; 2970 2971 /* Create the new histogram with our variable */ 2972 ret = event_hist_trigger_parse(&trigger_hist_cmd, file, 2973 "", "hist", cmd); 2974 if (ret) { 2975 kfree(cmd); 2976 kfree(var_hist->cmd); 2977 kfree(var_hist); 2978 hist_err(tr, HIST_ERR_HIST_CREATE_FAIL, errpos(field_name)); 2979 return ERR_PTR(ret); 2980 } 2981 2982 kfree(cmd); 2983 2984 /* If we can't find the variable, something went wrong */ 2985 event_var = find_synthetic_field_var(target_hist_data, subsys_name, 2986 event_name, field_name); 2987 if (IS_ERR_OR_NULL(event_var)) { 2988 kfree(var_hist->cmd); 2989 kfree(var_hist); 2990 hist_err(tr, HIST_ERR_SYNTH_VAR_NOT_FOUND, errpos(field_name)); 2991 return ERR_PTR(-EINVAL); 2992 } 2993 2994 n = target_hist_data->n_field_var_hists; 2995 target_hist_data->field_var_hists[n] = var_hist; 2996 target_hist_data->n_field_var_hists++; 2997 2998 return event_var; 2999 } 3000 3001 static struct hist_field * 3002 find_target_event_var(struct hist_trigger_data *hist_data, 3003 char *subsys_name, char *event_name, char *var_name) 3004 { 3005 struct trace_event_file *file = hist_data->event_file; 3006 struct hist_field *hist_field = NULL; 3007 3008 if (subsys_name) { 3009 struct trace_event_call *call; 3010 3011 if (!event_name) 3012 return NULL; 3013 3014 call = file->event_call; 3015 3016 if (strcmp(subsys_name, call->class->system) != 0) 3017 return NULL; 3018 3019 if (strcmp(event_name, trace_event_name(call)) != 0) 3020 return NULL; 3021 } 3022 3023 hist_field = find_var_field(hist_data, var_name); 3024 3025 return hist_field; 3026 } 3027 3028 static inline void __update_field_vars(struct tracing_map_elt *elt, 3029 struct trace_buffer *buffer, 3030 struct ring_buffer_event *rbe, 3031 void *rec, 3032 struct field_var **field_vars, 3033 unsigned int n_field_vars, 3034 unsigned int field_var_str_start) 3035 { 3036 struct hist_elt_data *elt_data = elt->private_data; 3037 unsigned int i, j, var_idx; 3038 u64 var_val; 3039 3040 for (i = 0, j = field_var_str_start; i < n_field_vars; i++) { 3041 struct field_var *field_var = field_vars[i]; 3042 struct hist_field *var = field_var->var; 3043 struct hist_field *val = field_var->val; 3044 3045 var_val = val->fn(val, elt, buffer, rbe, rec); 3046 var_idx = var->var.idx; 3047 3048 if (val->flags & HIST_FIELD_FL_STRING) { 3049 char *str = elt_data->field_var_str[j++]; 3050 char *val_str = (char *)(uintptr_t)var_val; 3051 unsigned int size; 3052 3053 size = min(val->size, STR_VAR_LEN_MAX); 3054 strscpy(str, val_str, size); 3055 var_val = (u64)(uintptr_t)str; 3056 } 3057 tracing_map_set_var(elt, var_idx, var_val); 3058 } 3059 } 3060 3061 static void update_field_vars(struct hist_trigger_data *hist_data, 3062 struct tracing_map_elt *elt, 3063 struct trace_buffer *buffer, 3064 struct ring_buffer_event *rbe, 3065 void *rec) 3066 { 3067 __update_field_vars(elt, buffer, rbe, rec, hist_data->field_vars, 3068 hist_data->n_field_vars, 0); 3069 } 3070 3071 static void save_track_data_vars(struct hist_trigger_data *hist_data, 3072 struct tracing_map_elt *elt, 3073 struct trace_buffer *buffer, void *rec, 3074 struct ring_buffer_event *rbe, void *key, 3075 struct action_data *data, u64 *var_ref_vals) 3076 { 3077 __update_field_vars(elt, buffer, rbe, rec, hist_data->save_vars, 3078 hist_data->n_save_vars, hist_data->n_field_var_str); 3079 } 3080 3081 static struct hist_field *create_var(struct hist_trigger_data *hist_data, 3082 struct trace_event_file *file, 3083 char *name, int size, const char *type) 3084 { 3085 struct hist_field *var; 3086 int idx; 3087 3088 if (find_var(hist_data, file, name) && !hist_data->remove) { 3089 var = ERR_PTR(-EINVAL); 3090 goto out; 3091 } 3092 3093 var = kzalloc(sizeof(struct hist_field), GFP_KERNEL); 3094 if (!var) { 3095 var = ERR_PTR(-ENOMEM); 3096 goto out; 3097 } 3098 3099 idx = tracing_map_add_var(hist_data->map); 3100 if (idx < 0) { 3101 kfree(var); 3102 var = ERR_PTR(-EINVAL); 3103 goto out; 3104 } 3105 3106 var->ref = 1; 3107 var->flags = HIST_FIELD_FL_VAR; 3108 var->var.idx = idx; 3109 var->var.hist_data = var->hist_data = hist_data; 3110 var->size = size; 3111 var->var.name = kstrdup(name, GFP_KERNEL); 3112 var->type = kstrdup_const(type, GFP_KERNEL); 3113 if (!var->var.name || !var->type) { 3114 kfree_const(var->type); 3115 kfree(var->var.name); 3116 kfree(var); 3117 var = ERR_PTR(-ENOMEM); 3118 } 3119 out: 3120 return var; 3121 } 3122 3123 static struct field_var *create_field_var(struct hist_trigger_data *hist_data, 3124 struct trace_event_file *file, 3125 char *field_name) 3126 { 3127 struct hist_field *val = NULL, *var = NULL; 3128 unsigned long flags = HIST_FIELD_FL_VAR; 3129 struct trace_array *tr = file->tr; 3130 struct field_var *field_var; 3131 int ret = 0; 3132 3133 if (hist_data->n_field_vars >= SYNTH_FIELDS_MAX) { 3134 hist_err(tr, HIST_ERR_TOO_MANY_FIELD_VARS, errpos(field_name)); 3135 ret = -EINVAL; 3136 goto err; 3137 } 3138 3139 val = parse_atom(hist_data, file, field_name, &flags, NULL); 3140 if (IS_ERR(val)) { 3141 hist_err(tr, HIST_ERR_FIELD_VAR_PARSE_FAIL, errpos(field_name)); 3142 ret = PTR_ERR(val); 3143 goto err; 3144 } 3145 3146 var = create_var(hist_data, file, field_name, val->size, val->type); 3147 if (IS_ERR(var)) { 3148 hist_err(tr, HIST_ERR_VAR_CREATE_FIND_FAIL, errpos(field_name)); 3149 kfree(val); 3150 ret = PTR_ERR(var); 3151 goto err; 3152 } 3153 3154 field_var = kzalloc(sizeof(struct field_var), GFP_KERNEL); 3155 if (!field_var) { 3156 kfree(val); 3157 kfree(var); 3158 ret = -ENOMEM; 3159 goto err; 3160 } 3161 3162 field_var->var = var; 3163 field_var->val = val; 3164 out: 3165 return field_var; 3166 err: 3167 field_var = ERR_PTR(ret); 3168 goto out; 3169 } 3170 3171 /** 3172 * create_target_field_var - Automatically create a variable for a field 3173 * @target_hist_data: The target hist trigger 3174 * @subsys_name: Optional subsystem name 3175 * @event_name: Optional event name 3176 * @var_name: The name of the field (and the resulting variable) 3177 * 3178 * Hist trigger actions fetch data from variables, not directly from 3179 * events. However, for convenience, users are allowed to directly 3180 * specify an event field in an action, which will be automatically 3181 * converted into a variable on their behalf. 3182 3183 * This function creates a field variable with the name var_name on 3184 * the hist trigger currently being defined on the target event. If 3185 * subsys_name and event_name are specified, this function simply 3186 * verifies that they do in fact match the target event subsystem and 3187 * event name. 3188 * 3189 * Return: The variable created for the field. 3190 */ 3191 static struct field_var * 3192 create_target_field_var(struct hist_trigger_data *target_hist_data, 3193 char *subsys_name, char *event_name, char *var_name) 3194 { 3195 struct trace_event_file *file = target_hist_data->event_file; 3196 3197 if (subsys_name) { 3198 struct trace_event_call *call; 3199 3200 if (!event_name) 3201 return NULL; 3202 3203 call = file->event_call; 3204 3205 if (strcmp(subsys_name, call->class->system) != 0) 3206 return NULL; 3207 3208 if (strcmp(event_name, trace_event_name(call)) != 0) 3209 return NULL; 3210 } 3211 3212 return create_field_var(target_hist_data, file, var_name); 3213 } 3214 3215 static bool check_track_val_max(u64 track_val, u64 var_val) 3216 { 3217 if (var_val <= track_val) 3218 return false; 3219 3220 return true; 3221 } 3222 3223 static bool check_track_val_changed(u64 track_val, u64 var_val) 3224 { 3225 if (var_val == track_val) 3226 return false; 3227 3228 return true; 3229 } 3230 3231 static u64 get_track_val(struct hist_trigger_data *hist_data, 3232 struct tracing_map_elt *elt, 3233 struct action_data *data) 3234 { 3235 unsigned int track_var_idx = data->track_data.track_var->var.idx; 3236 u64 track_val; 3237 3238 track_val = tracing_map_read_var(elt, track_var_idx); 3239 3240 return track_val; 3241 } 3242 3243 static void save_track_val(struct hist_trigger_data *hist_data, 3244 struct tracing_map_elt *elt, 3245 struct action_data *data, u64 var_val) 3246 { 3247 unsigned int track_var_idx = data->track_data.track_var->var.idx; 3248 3249 tracing_map_set_var(elt, track_var_idx, var_val); 3250 } 3251 3252 static void save_track_data(struct hist_trigger_data *hist_data, 3253 struct tracing_map_elt *elt, 3254 struct trace_buffer *buffer, void *rec, 3255 struct ring_buffer_event *rbe, void *key, 3256 struct action_data *data, u64 *var_ref_vals) 3257 { 3258 if (data->track_data.save_data) 3259 data->track_data.save_data(hist_data, elt, buffer, rec, rbe, 3260 key, data, var_ref_vals); 3261 } 3262 3263 static bool check_track_val(struct tracing_map_elt *elt, 3264 struct action_data *data, 3265 u64 var_val) 3266 { 3267 struct hist_trigger_data *hist_data; 3268 u64 track_val; 3269 3270 hist_data = data->track_data.track_var->hist_data; 3271 track_val = get_track_val(hist_data, elt, data); 3272 3273 return data->track_data.check_val(track_val, var_val); 3274 } 3275 3276 #ifdef CONFIG_TRACER_SNAPSHOT 3277 static bool cond_snapshot_update(struct trace_array *tr, void *cond_data) 3278 { 3279 /* called with tr->max_lock held */ 3280 struct track_data *track_data = tr->cond_snapshot->cond_data; 3281 struct hist_elt_data *elt_data, *track_elt_data; 3282 struct snapshot_context *context = cond_data; 3283 struct action_data *action; 3284 u64 track_val; 3285 3286 if (!track_data) 3287 return false; 3288 3289 action = track_data->action_data; 3290 3291 track_val = get_track_val(track_data->hist_data, context->elt, 3292 track_data->action_data); 3293 3294 if (!action->track_data.check_val(track_data->track_val, track_val)) 3295 return false; 3296 3297 track_data->track_val = track_val; 3298 memcpy(track_data->key, context->key, track_data->key_len); 3299 3300 elt_data = context->elt->private_data; 3301 track_elt_data = track_data->elt.private_data; 3302 if (elt_data->comm) 3303 strncpy(track_elt_data->comm, elt_data->comm, TASK_COMM_LEN); 3304 3305 track_data->updated = true; 3306 3307 return true; 3308 } 3309 3310 static void save_track_data_snapshot(struct hist_trigger_data *hist_data, 3311 struct tracing_map_elt *elt, 3312 struct trace_buffer *buffer, void *rec, 3313 struct ring_buffer_event *rbe, void *key, 3314 struct action_data *data, 3315 u64 *var_ref_vals) 3316 { 3317 struct trace_event_file *file = hist_data->event_file; 3318 struct snapshot_context context; 3319 3320 context.elt = elt; 3321 context.key = key; 3322 3323 tracing_snapshot_cond(file->tr, &context); 3324 } 3325 3326 static void hist_trigger_print_key(struct seq_file *m, 3327 struct hist_trigger_data *hist_data, 3328 void *key, 3329 struct tracing_map_elt *elt); 3330 3331 static struct action_data *snapshot_action(struct hist_trigger_data *hist_data) 3332 { 3333 unsigned int i; 3334 3335 if (!hist_data->n_actions) 3336 return NULL; 3337 3338 for (i = 0; i < hist_data->n_actions; i++) { 3339 struct action_data *data = hist_data->actions[i]; 3340 3341 if (data->action == ACTION_SNAPSHOT) 3342 return data; 3343 } 3344 3345 return NULL; 3346 } 3347 3348 static void track_data_snapshot_print(struct seq_file *m, 3349 struct hist_trigger_data *hist_data) 3350 { 3351 struct trace_event_file *file = hist_data->event_file; 3352 struct track_data *track_data; 3353 struct action_data *action; 3354 3355 track_data = tracing_cond_snapshot_data(file->tr); 3356 if (!track_data) 3357 return; 3358 3359 if (!track_data->updated) 3360 return; 3361 3362 action = snapshot_action(hist_data); 3363 if (!action) 3364 return; 3365 3366 seq_puts(m, "\nSnapshot taken (see tracing/snapshot). Details:\n"); 3367 seq_printf(m, "\ttriggering value { %s(%s) }: %10llu", 3368 action->handler == HANDLER_ONMAX ? "onmax" : "onchange", 3369 action->track_data.var_str, track_data->track_val); 3370 3371 seq_puts(m, "\ttriggered by event with key: "); 3372 hist_trigger_print_key(m, hist_data, track_data->key, &track_data->elt); 3373 seq_putc(m, '\n'); 3374 } 3375 #else 3376 static bool cond_snapshot_update(struct trace_array *tr, void *cond_data) 3377 { 3378 return false; 3379 } 3380 static void save_track_data_snapshot(struct hist_trigger_data *hist_data, 3381 struct tracing_map_elt *elt, 3382 struct trace_buffer *buffer, void *rec, 3383 struct ring_buffer_event *rbe, void *key, 3384 struct action_data *data, 3385 u64 *var_ref_vals) {} 3386 static void track_data_snapshot_print(struct seq_file *m, 3387 struct hist_trigger_data *hist_data) {} 3388 #endif /* CONFIG_TRACER_SNAPSHOT */ 3389 3390 static void track_data_print(struct seq_file *m, 3391 struct hist_trigger_data *hist_data, 3392 struct tracing_map_elt *elt, 3393 struct action_data *data) 3394 { 3395 u64 track_val = get_track_val(hist_data, elt, data); 3396 unsigned int i, save_var_idx; 3397 3398 if (data->handler == HANDLER_ONMAX) 3399 seq_printf(m, "\n\tmax: %10llu", track_val); 3400 else if (data->handler == HANDLER_ONCHANGE) 3401 seq_printf(m, "\n\tchanged: %10llu", track_val); 3402 3403 if (data->action == ACTION_SNAPSHOT) 3404 return; 3405 3406 for (i = 0; i < hist_data->n_save_vars; i++) { 3407 struct hist_field *save_val = hist_data->save_vars[i]->val; 3408 struct hist_field *save_var = hist_data->save_vars[i]->var; 3409 u64 val; 3410 3411 save_var_idx = save_var->var.idx; 3412 3413 val = tracing_map_read_var(elt, save_var_idx); 3414 3415 if (save_val->flags & HIST_FIELD_FL_STRING) { 3416 seq_printf(m, " %s: %-32s", save_var->var.name, 3417 (char *)(uintptr_t)(val)); 3418 } else 3419 seq_printf(m, " %s: %10llu", save_var->var.name, val); 3420 } 3421 } 3422 3423 static void ontrack_action(struct hist_trigger_data *hist_data, 3424 struct tracing_map_elt *elt, 3425 struct trace_buffer *buffer, void *rec, 3426 struct ring_buffer_event *rbe, void *key, 3427 struct action_data *data, u64 *var_ref_vals) 3428 { 3429 u64 var_val = var_ref_vals[data->track_data.var_ref->var_ref_idx]; 3430 3431 if (check_track_val(elt, data, var_val)) { 3432 save_track_val(hist_data, elt, data, var_val); 3433 save_track_data(hist_data, elt, buffer, rec, rbe, 3434 key, data, var_ref_vals); 3435 } 3436 } 3437 3438 static void action_data_destroy(struct action_data *data) 3439 { 3440 unsigned int i; 3441 3442 lockdep_assert_held(&event_mutex); 3443 3444 kfree(data->action_name); 3445 3446 for (i = 0; i < data->n_params; i++) 3447 kfree(data->params[i]); 3448 3449 if (data->synth_event) 3450 data->synth_event->ref--; 3451 3452 kfree(data->synth_event_name); 3453 3454 kfree(data); 3455 } 3456 3457 static void track_data_destroy(struct hist_trigger_data *hist_data, 3458 struct action_data *data) 3459 { 3460 struct trace_event_file *file = hist_data->event_file; 3461 3462 destroy_hist_field(data->track_data.track_var, 0); 3463 3464 if (data->action == ACTION_SNAPSHOT) { 3465 struct track_data *track_data; 3466 3467 track_data = tracing_cond_snapshot_data(file->tr); 3468 if (track_data && track_data->hist_data == hist_data) { 3469 tracing_snapshot_cond_disable(file->tr); 3470 track_data_free(track_data); 3471 } 3472 } 3473 3474 kfree(data->track_data.var_str); 3475 3476 action_data_destroy(data); 3477 } 3478 3479 static int action_create(struct hist_trigger_data *hist_data, 3480 struct action_data *data); 3481 3482 static int track_data_create(struct hist_trigger_data *hist_data, 3483 struct action_data *data) 3484 { 3485 struct hist_field *var_field, *ref_field, *track_var = NULL; 3486 struct trace_event_file *file = hist_data->event_file; 3487 struct trace_array *tr = file->tr; 3488 char *track_data_var_str; 3489 int ret = 0; 3490 3491 track_data_var_str = data->track_data.var_str; 3492 if (track_data_var_str[0] != '$') { 3493 hist_err(tr, HIST_ERR_ONX_NOT_VAR, errpos(track_data_var_str)); 3494 return -EINVAL; 3495 } 3496 track_data_var_str++; 3497 3498 var_field = find_target_event_var(hist_data, NULL, NULL, track_data_var_str); 3499 if (!var_field) { 3500 hist_err(tr, HIST_ERR_ONX_VAR_NOT_FOUND, errpos(track_data_var_str)); 3501 return -EINVAL; 3502 } 3503 3504 ref_field = create_var_ref(hist_data, var_field, NULL, NULL); 3505 if (!ref_field) 3506 return -ENOMEM; 3507 3508 data->track_data.var_ref = ref_field; 3509 3510 if (data->handler == HANDLER_ONMAX) 3511 track_var = create_var(hist_data, file, "__max", sizeof(u64), "u64"); 3512 if (IS_ERR(track_var)) { 3513 hist_err(tr, HIST_ERR_ONX_VAR_CREATE_FAIL, 0); 3514 ret = PTR_ERR(track_var); 3515 goto out; 3516 } 3517 3518 if (data->handler == HANDLER_ONCHANGE) 3519 track_var = create_var(hist_data, file, "__change", sizeof(u64), "u64"); 3520 if (IS_ERR(track_var)) { 3521 hist_err(tr, HIST_ERR_ONX_VAR_CREATE_FAIL, 0); 3522 ret = PTR_ERR(track_var); 3523 goto out; 3524 } 3525 data->track_data.track_var = track_var; 3526 3527 ret = action_create(hist_data, data); 3528 out: 3529 return ret; 3530 } 3531 3532 static int parse_action_params(struct trace_array *tr, char *params, 3533 struct action_data *data) 3534 { 3535 char *param, *saved_param; 3536 bool first_param = true; 3537 int ret = 0; 3538 3539 while (params) { 3540 if (data->n_params >= SYNTH_FIELDS_MAX) { 3541 hist_err(tr, HIST_ERR_TOO_MANY_PARAMS, 0); 3542 goto out; 3543 } 3544 3545 param = strsep(¶ms, ","); 3546 if (!param) { 3547 hist_err(tr, HIST_ERR_PARAM_NOT_FOUND, 0); 3548 ret = -EINVAL; 3549 goto out; 3550 } 3551 3552 param = strstrip(param); 3553 if (strlen(param) < 2) { 3554 hist_err(tr, HIST_ERR_INVALID_PARAM, errpos(param)); 3555 ret = -EINVAL; 3556 goto out; 3557 } 3558 3559 saved_param = kstrdup(param, GFP_KERNEL); 3560 if (!saved_param) { 3561 ret = -ENOMEM; 3562 goto out; 3563 } 3564 3565 if (first_param && data->use_trace_keyword) { 3566 data->synth_event_name = saved_param; 3567 first_param = false; 3568 continue; 3569 } 3570 first_param = false; 3571 3572 data->params[data->n_params++] = saved_param; 3573 } 3574 out: 3575 return ret; 3576 } 3577 3578 static int action_parse(struct trace_array *tr, char *str, struct action_data *data, 3579 enum handler_id handler) 3580 { 3581 char *action_name; 3582 int ret = 0; 3583 3584 strsep(&str, "."); 3585 if (!str) { 3586 hist_err(tr, HIST_ERR_ACTION_NOT_FOUND, 0); 3587 ret = -EINVAL; 3588 goto out; 3589 } 3590 3591 action_name = strsep(&str, "("); 3592 if (!action_name || !str) { 3593 hist_err(tr, HIST_ERR_ACTION_NOT_FOUND, 0); 3594 ret = -EINVAL; 3595 goto out; 3596 } 3597 3598 if (str_has_prefix(action_name, "save")) { 3599 char *params = strsep(&str, ")"); 3600 3601 if (!params) { 3602 hist_err(tr, HIST_ERR_NO_SAVE_PARAMS, 0); 3603 ret = -EINVAL; 3604 goto out; 3605 } 3606 3607 ret = parse_action_params(tr, params, data); 3608 if (ret) 3609 goto out; 3610 3611 if (handler == HANDLER_ONMAX) 3612 data->track_data.check_val = check_track_val_max; 3613 else if (handler == HANDLER_ONCHANGE) 3614 data->track_data.check_val = check_track_val_changed; 3615 else { 3616 hist_err(tr, HIST_ERR_ACTION_MISMATCH, errpos(action_name)); 3617 ret = -EINVAL; 3618 goto out; 3619 } 3620 3621 data->track_data.save_data = save_track_data_vars; 3622 data->fn = ontrack_action; 3623 data->action = ACTION_SAVE; 3624 } else if (str_has_prefix(action_name, "snapshot")) { 3625 char *params = strsep(&str, ")"); 3626 3627 if (!str) { 3628 hist_err(tr, HIST_ERR_NO_CLOSING_PAREN, errpos(params)); 3629 ret = -EINVAL; 3630 goto out; 3631 } 3632 3633 if (handler == HANDLER_ONMAX) 3634 data->track_data.check_val = check_track_val_max; 3635 else if (handler == HANDLER_ONCHANGE) 3636 data->track_data.check_val = check_track_val_changed; 3637 else { 3638 hist_err(tr, HIST_ERR_ACTION_MISMATCH, errpos(action_name)); 3639 ret = -EINVAL; 3640 goto out; 3641 } 3642 3643 data->track_data.save_data = save_track_data_snapshot; 3644 data->fn = ontrack_action; 3645 data->action = ACTION_SNAPSHOT; 3646 } else { 3647 char *params = strsep(&str, ")"); 3648 3649 if (str_has_prefix(action_name, "trace")) 3650 data->use_trace_keyword = true; 3651 3652 if (params) { 3653 ret = parse_action_params(tr, params, data); 3654 if (ret) 3655 goto out; 3656 } 3657 3658 if (handler == HANDLER_ONMAX) 3659 data->track_data.check_val = check_track_val_max; 3660 else if (handler == HANDLER_ONCHANGE) 3661 data->track_data.check_val = check_track_val_changed; 3662 3663 if (handler != HANDLER_ONMATCH) { 3664 data->track_data.save_data = action_trace; 3665 data->fn = ontrack_action; 3666 } else 3667 data->fn = action_trace; 3668 3669 data->action = ACTION_TRACE; 3670 } 3671 3672 data->action_name = kstrdup(action_name, GFP_KERNEL); 3673 if (!data->action_name) { 3674 ret = -ENOMEM; 3675 goto out; 3676 } 3677 3678 data->handler = handler; 3679 out: 3680 return ret; 3681 } 3682 3683 static struct action_data *track_data_parse(struct hist_trigger_data *hist_data, 3684 char *str, enum handler_id handler) 3685 { 3686 struct action_data *data; 3687 int ret = -EINVAL; 3688 char *var_str; 3689 3690 data = kzalloc(sizeof(*data), GFP_KERNEL); 3691 if (!data) 3692 return ERR_PTR(-ENOMEM); 3693 3694 var_str = strsep(&str, ")"); 3695 if (!var_str || !str) { 3696 ret = -EINVAL; 3697 goto free; 3698 } 3699 3700 data->track_data.var_str = kstrdup(var_str, GFP_KERNEL); 3701 if (!data->track_data.var_str) { 3702 ret = -ENOMEM; 3703 goto free; 3704 } 3705 3706 ret = action_parse(hist_data->event_file->tr, str, data, handler); 3707 if (ret) 3708 goto free; 3709 out: 3710 return data; 3711 free: 3712 track_data_destroy(hist_data, data); 3713 data = ERR_PTR(ret); 3714 goto out; 3715 } 3716 3717 static void onmatch_destroy(struct action_data *data) 3718 { 3719 kfree(data->match_data.event); 3720 kfree(data->match_data.event_system); 3721 3722 action_data_destroy(data); 3723 } 3724 3725 static void destroy_field_var(struct field_var *field_var) 3726 { 3727 if (!field_var) 3728 return; 3729 3730 destroy_hist_field(field_var->var, 0); 3731 destroy_hist_field(field_var->val, 0); 3732 3733 kfree(field_var); 3734 } 3735 3736 static void destroy_field_vars(struct hist_trigger_data *hist_data) 3737 { 3738 unsigned int i; 3739 3740 for (i = 0; i < hist_data->n_field_vars; i++) 3741 destroy_field_var(hist_data->field_vars[i]); 3742 3743 for (i = 0; i < hist_data->n_save_vars; i++) 3744 destroy_field_var(hist_data->save_vars[i]); 3745 } 3746 3747 static void save_field_var(struct hist_trigger_data *hist_data, 3748 struct field_var *field_var) 3749 { 3750 hist_data->field_vars[hist_data->n_field_vars++] = field_var; 3751 3752 if (field_var->val->flags & HIST_FIELD_FL_STRING) 3753 hist_data->n_field_var_str++; 3754 } 3755 3756 3757 static int check_synth_field(struct synth_event *event, 3758 struct hist_field *hist_field, 3759 unsigned int field_pos) 3760 { 3761 struct synth_field *field; 3762 3763 if (field_pos >= event->n_fields) 3764 return -EINVAL; 3765 3766 field = event->fields[field_pos]; 3767 3768 /* 3769 * A dynamic string synth field can accept static or 3770 * dynamic. A static string synth field can only accept a 3771 * same-sized static string, which is checked for later. 3772 */ 3773 if (strstr(hist_field->type, "char[") && field->is_string 3774 && field->is_dynamic) 3775 return 0; 3776 3777 if (strcmp(field->type, hist_field->type) != 0) { 3778 if (field->size != hist_field->size || 3779 (!field->is_string && field->is_signed != hist_field->is_signed)) 3780 return -EINVAL; 3781 } 3782 3783 return 0; 3784 } 3785 3786 static struct hist_field * 3787 trace_action_find_var(struct hist_trigger_data *hist_data, 3788 struct action_data *data, 3789 char *system, char *event, char *var) 3790 { 3791 struct trace_array *tr = hist_data->event_file->tr; 3792 struct hist_field *hist_field; 3793 3794 var++; /* skip '$' */ 3795 3796 hist_field = find_target_event_var(hist_data, system, event, var); 3797 if (!hist_field) { 3798 if (!system && data->handler == HANDLER_ONMATCH) { 3799 system = data->match_data.event_system; 3800 event = data->match_data.event; 3801 } 3802 3803 hist_field = find_event_var(hist_data, system, event, var); 3804 } 3805 3806 if (!hist_field) 3807 hist_err(tr, HIST_ERR_PARAM_NOT_FOUND, errpos(var)); 3808 3809 return hist_field; 3810 } 3811 3812 static struct hist_field * 3813 trace_action_create_field_var(struct hist_trigger_data *hist_data, 3814 struct action_data *data, char *system, 3815 char *event, char *var) 3816 { 3817 struct hist_field *hist_field = NULL; 3818 struct field_var *field_var; 3819 3820 /* 3821 * First try to create a field var on the target event (the 3822 * currently being defined). This will create a variable for 3823 * unqualified fields on the target event, or if qualified, 3824 * target fields that have qualified names matching the target. 3825 */ 3826 field_var = create_target_field_var(hist_data, system, event, var); 3827 3828 if (field_var && !IS_ERR(field_var)) { 3829 save_field_var(hist_data, field_var); 3830 hist_field = field_var->var; 3831 } else { 3832 field_var = NULL; 3833 /* 3834 * If no explicit system.event is specified, default to 3835 * looking for fields on the onmatch(system.event.xxx) 3836 * event. 3837 */ 3838 if (!system && data->handler == HANDLER_ONMATCH) { 3839 system = data->match_data.event_system; 3840 event = data->match_data.event; 3841 } 3842 3843 if (!event) 3844 goto free; 3845 /* 3846 * At this point, we're looking at a field on another 3847 * event. Because we can't modify a hist trigger on 3848 * another event to add a variable for a field, we need 3849 * to create a new trigger on that event and create the 3850 * variable at the same time. 3851 */ 3852 hist_field = create_field_var_hist(hist_data, system, event, var); 3853 if (IS_ERR(hist_field)) 3854 goto free; 3855 } 3856 out: 3857 return hist_field; 3858 free: 3859 destroy_field_var(field_var); 3860 hist_field = NULL; 3861 goto out; 3862 } 3863 3864 static int trace_action_create(struct hist_trigger_data *hist_data, 3865 struct action_data *data) 3866 { 3867 struct trace_array *tr = hist_data->event_file->tr; 3868 char *event_name, *param, *system = NULL; 3869 struct hist_field *hist_field, *var_ref; 3870 unsigned int i; 3871 unsigned int field_pos = 0; 3872 struct synth_event *event; 3873 char *synth_event_name; 3874 int var_ref_idx, ret = 0; 3875 3876 lockdep_assert_held(&event_mutex); 3877 3878 if (data->use_trace_keyword) 3879 synth_event_name = data->synth_event_name; 3880 else 3881 synth_event_name = data->action_name; 3882 3883 event = find_synth_event(synth_event_name); 3884 if (!event) { 3885 hist_err(tr, HIST_ERR_SYNTH_EVENT_NOT_FOUND, errpos(synth_event_name)); 3886 return -EINVAL; 3887 } 3888 3889 event->ref++; 3890 3891 for (i = 0; i < data->n_params; i++) { 3892 char *p; 3893 3894 p = param = kstrdup(data->params[i], GFP_KERNEL); 3895 if (!param) { 3896 ret = -ENOMEM; 3897 goto err; 3898 } 3899 3900 system = strsep(¶m, "."); 3901 if (!param) { 3902 param = (char *)system; 3903 system = event_name = NULL; 3904 } else { 3905 event_name = strsep(¶m, "."); 3906 if (!param) { 3907 kfree(p); 3908 ret = -EINVAL; 3909 goto err; 3910 } 3911 } 3912 3913 if (param[0] == '$') 3914 hist_field = trace_action_find_var(hist_data, data, 3915 system, event_name, 3916 param); 3917 else 3918 hist_field = trace_action_create_field_var(hist_data, 3919 data, 3920 system, 3921 event_name, 3922 param); 3923 3924 if (!hist_field) { 3925 kfree(p); 3926 ret = -EINVAL; 3927 goto err; 3928 } 3929 3930 if (check_synth_field(event, hist_field, field_pos) == 0) { 3931 var_ref = create_var_ref(hist_data, hist_field, 3932 system, event_name); 3933 if (!var_ref) { 3934 kfree(p); 3935 ret = -ENOMEM; 3936 goto err; 3937 } 3938 3939 var_ref_idx = find_var_ref_idx(hist_data, var_ref); 3940 if (WARN_ON(var_ref_idx < 0)) { 3941 kfree(p); 3942 ret = var_ref_idx; 3943 goto err; 3944 } 3945 3946 data->var_ref_idx[i] = var_ref_idx; 3947 3948 field_pos++; 3949 kfree(p); 3950 continue; 3951 } 3952 3953 hist_err(tr, HIST_ERR_SYNTH_TYPE_MISMATCH, errpos(param)); 3954 kfree(p); 3955 ret = -EINVAL; 3956 goto err; 3957 } 3958 3959 if (field_pos != event->n_fields) { 3960 hist_err(tr, HIST_ERR_SYNTH_COUNT_MISMATCH, errpos(event->name)); 3961 ret = -EINVAL; 3962 goto err; 3963 } 3964 3965 data->synth_event = event; 3966 out: 3967 return ret; 3968 err: 3969 event->ref--; 3970 3971 goto out; 3972 } 3973 3974 static int action_create(struct hist_trigger_data *hist_data, 3975 struct action_data *data) 3976 { 3977 struct trace_event_file *file = hist_data->event_file; 3978 struct trace_array *tr = file->tr; 3979 struct track_data *track_data; 3980 struct field_var *field_var; 3981 unsigned int i; 3982 char *param; 3983 int ret = 0; 3984 3985 if (data->action == ACTION_TRACE) 3986 return trace_action_create(hist_data, data); 3987 3988 if (data->action == ACTION_SNAPSHOT) { 3989 track_data = track_data_alloc(hist_data->key_size, data, hist_data); 3990 if (IS_ERR(track_data)) { 3991 ret = PTR_ERR(track_data); 3992 goto out; 3993 } 3994 3995 ret = tracing_snapshot_cond_enable(file->tr, track_data, 3996 cond_snapshot_update); 3997 if (ret) 3998 track_data_free(track_data); 3999 4000 goto out; 4001 } 4002 4003 if (data->action == ACTION_SAVE) { 4004 if (hist_data->n_save_vars) { 4005 ret = -EEXIST; 4006 hist_err(tr, HIST_ERR_TOO_MANY_SAVE_ACTIONS, 0); 4007 goto out; 4008 } 4009 4010 for (i = 0; i < data->n_params; i++) { 4011 param = kstrdup(data->params[i], GFP_KERNEL); 4012 if (!param) { 4013 ret = -ENOMEM; 4014 goto out; 4015 } 4016 4017 field_var = create_target_field_var(hist_data, NULL, NULL, param); 4018 if (IS_ERR(field_var)) { 4019 hist_err(tr, HIST_ERR_FIELD_VAR_CREATE_FAIL, 4020 errpos(param)); 4021 ret = PTR_ERR(field_var); 4022 kfree(param); 4023 goto out; 4024 } 4025 4026 hist_data->save_vars[hist_data->n_save_vars++] = field_var; 4027 if (field_var->val->flags & HIST_FIELD_FL_STRING) 4028 hist_data->n_save_var_str++; 4029 kfree(param); 4030 } 4031 } 4032 out: 4033 return ret; 4034 } 4035 4036 static int onmatch_create(struct hist_trigger_data *hist_data, 4037 struct action_data *data) 4038 { 4039 return action_create(hist_data, data); 4040 } 4041 4042 static struct action_data *onmatch_parse(struct trace_array *tr, char *str) 4043 { 4044 char *match_event, *match_event_system; 4045 struct action_data *data; 4046 int ret = -EINVAL; 4047 4048 data = kzalloc(sizeof(*data), GFP_KERNEL); 4049 if (!data) 4050 return ERR_PTR(-ENOMEM); 4051 4052 match_event = strsep(&str, ")"); 4053 if (!match_event || !str) { 4054 hist_err(tr, HIST_ERR_NO_CLOSING_PAREN, errpos(match_event)); 4055 goto free; 4056 } 4057 4058 match_event_system = strsep(&match_event, "."); 4059 if (!match_event) { 4060 hist_err(tr, HIST_ERR_SUBSYS_NOT_FOUND, errpos(match_event_system)); 4061 goto free; 4062 } 4063 4064 if (IS_ERR(event_file(tr, match_event_system, match_event))) { 4065 hist_err(tr, HIST_ERR_INVALID_SUBSYS_EVENT, errpos(match_event)); 4066 goto free; 4067 } 4068 4069 data->match_data.event = kstrdup(match_event, GFP_KERNEL); 4070 if (!data->match_data.event) { 4071 ret = -ENOMEM; 4072 goto free; 4073 } 4074 4075 data->match_data.event_system = kstrdup(match_event_system, GFP_KERNEL); 4076 if (!data->match_data.event_system) { 4077 ret = -ENOMEM; 4078 goto free; 4079 } 4080 4081 ret = action_parse(tr, str, data, HANDLER_ONMATCH); 4082 if (ret) 4083 goto free; 4084 out: 4085 return data; 4086 free: 4087 onmatch_destroy(data); 4088 data = ERR_PTR(ret); 4089 goto out; 4090 } 4091 4092 static int create_hitcount_val(struct hist_trigger_data *hist_data) 4093 { 4094 hist_data->fields[HITCOUNT_IDX] = 4095 create_hist_field(hist_data, NULL, HIST_FIELD_FL_HITCOUNT, NULL); 4096 if (!hist_data->fields[HITCOUNT_IDX]) 4097 return -ENOMEM; 4098 4099 hist_data->n_vals++; 4100 hist_data->n_fields++; 4101 4102 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX)) 4103 return -EINVAL; 4104 4105 return 0; 4106 } 4107 4108 static int __create_val_field(struct hist_trigger_data *hist_data, 4109 unsigned int val_idx, 4110 struct trace_event_file *file, 4111 char *var_name, char *field_str, 4112 unsigned long flags) 4113 { 4114 struct hist_field *hist_field; 4115 int ret = 0, n_subexprs = 0; 4116 4117 hist_field = parse_expr(hist_data, file, field_str, flags, var_name, &n_subexprs); 4118 if (IS_ERR(hist_field)) { 4119 ret = PTR_ERR(hist_field); 4120 goto out; 4121 } 4122 4123 hist_data->fields[val_idx] = hist_field; 4124 4125 ++hist_data->n_vals; 4126 ++hist_data->n_fields; 4127 4128 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX)) 4129 ret = -EINVAL; 4130 out: 4131 return ret; 4132 } 4133 4134 static int create_val_field(struct hist_trigger_data *hist_data, 4135 unsigned int val_idx, 4136 struct trace_event_file *file, 4137 char *field_str) 4138 { 4139 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX)) 4140 return -EINVAL; 4141 4142 return __create_val_field(hist_data, val_idx, file, NULL, field_str, 0); 4143 } 4144 4145 static const char *no_comm = "(no comm)"; 4146 4147 static u64 hist_field_execname(struct hist_field *hist_field, 4148 struct tracing_map_elt *elt, 4149 struct trace_buffer *buffer, 4150 struct ring_buffer_event *rbe, 4151 void *event) 4152 { 4153 struct hist_elt_data *elt_data; 4154 4155 if (WARN_ON_ONCE(!elt)) 4156 return (u64)(unsigned long)no_comm; 4157 4158 elt_data = elt->private_data; 4159 4160 if (WARN_ON_ONCE(!elt_data->comm)) 4161 return (u64)(unsigned long)no_comm; 4162 4163 return (u64)(unsigned long)(elt_data->comm); 4164 } 4165 4166 /* Convert a var that points to common_pid.execname to a string */ 4167 static void update_var_execname(struct hist_field *hist_field) 4168 { 4169 hist_field->flags = HIST_FIELD_FL_STRING | HIST_FIELD_FL_VAR | 4170 HIST_FIELD_FL_EXECNAME; 4171 hist_field->size = MAX_FILTER_STR_VAL; 4172 hist_field->is_signed = 0; 4173 4174 kfree_const(hist_field->type); 4175 hist_field->type = "char[]"; 4176 4177 hist_field->fn = hist_field_execname; 4178 } 4179 4180 static int create_var_field(struct hist_trigger_data *hist_data, 4181 unsigned int val_idx, 4182 struct trace_event_file *file, 4183 char *var_name, char *expr_str) 4184 { 4185 struct trace_array *tr = hist_data->event_file->tr; 4186 unsigned long flags = 0; 4187 int ret; 4188 4189 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX)) 4190 return -EINVAL; 4191 4192 if (find_var(hist_data, file, var_name) && !hist_data->remove) { 4193 hist_err(tr, HIST_ERR_DUPLICATE_VAR, errpos(var_name)); 4194 return -EINVAL; 4195 } 4196 4197 flags |= HIST_FIELD_FL_VAR; 4198 hist_data->n_vars++; 4199 if (WARN_ON(hist_data->n_vars > TRACING_MAP_VARS_MAX)) 4200 return -EINVAL; 4201 4202 ret = __create_val_field(hist_data, val_idx, file, var_name, expr_str, flags); 4203 4204 if (!ret && hist_data->fields[val_idx]->flags & HIST_FIELD_FL_EXECNAME) 4205 update_var_execname(hist_data->fields[val_idx]); 4206 4207 if (!ret && hist_data->fields[val_idx]->flags & HIST_FIELD_FL_STRING) 4208 hist_data->fields[val_idx]->var_str_idx = hist_data->n_var_str++; 4209 4210 return ret; 4211 } 4212 4213 static int create_val_fields(struct hist_trigger_data *hist_data, 4214 struct trace_event_file *file) 4215 { 4216 char *fields_str, *field_str; 4217 unsigned int i, j = 1; 4218 int ret; 4219 4220 ret = create_hitcount_val(hist_data); 4221 if (ret) 4222 goto out; 4223 4224 fields_str = hist_data->attrs->vals_str; 4225 if (!fields_str) 4226 goto out; 4227 4228 for (i = 0, j = 1; i < TRACING_MAP_VALS_MAX && 4229 j < TRACING_MAP_VALS_MAX; i++) { 4230 field_str = strsep(&fields_str, ","); 4231 if (!field_str) 4232 break; 4233 4234 if (strcmp(field_str, "hitcount") == 0) 4235 continue; 4236 4237 ret = create_val_field(hist_data, j++, file, field_str); 4238 if (ret) 4239 goto out; 4240 } 4241 4242 if (fields_str && (strcmp(fields_str, "hitcount") != 0)) 4243 ret = -EINVAL; 4244 out: 4245 return ret; 4246 } 4247 4248 static int create_key_field(struct hist_trigger_data *hist_data, 4249 unsigned int key_idx, 4250 unsigned int key_offset, 4251 struct trace_event_file *file, 4252 char *field_str) 4253 { 4254 struct trace_array *tr = hist_data->event_file->tr; 4255 struct hist_field *hist_field = NULL; 4256 unsigned long flags = 0; 4257 unsigned int key_size; 4258 int ret = 0, n_subexprs = 0; 4259 4260 if (WARN_ON(key_idx >= HIST_FIELDS_MAX)) 4261 return -EINVAL; 4262 4263 flags |= HIST_FIELD_FL_KEY; 4264 4265 if (strcmp(field_str, "stacktrace") == 0) { 4266 flags |= HIST_FIELD_FL_STACKTRACE; 4267 key_size = sizeof(unsigned long) * HIST_STACKTRACE_DEPTH; 4268 hist_field = create_hist_field(hist_data, NULL, flags, NULL); 4269 } else { 4270 hist_field = parse_expr(hist_data, file, field_str, flags, 4271 NULL, &n_subexprs); 4272 if (IS_ERR(hist_field)) { 4273 ret = PTR_ERR(hist_field); 4274 goto out; 4275 } 4276 4277 if (field_has_hist_vars(hist_field, 0)) { 4278 hist_err(tr, HIST_ERR_INVALID_REF_KEY, errpos(field_str)); 4279 destroy_hist_field(hist_field, 0); 4280 ret = -EINVAL; 4281 goto out; 4282 } 4283 4284 key_size = hist_field->size; 4285 } 4286 4287 hist_data->fields[key_idx] = hist_field; 4288 4289 key_size = ALIGN(key_size, sizeof(u64)); 4290 hist_data->fields[key_idx]->size = key_size; 4291 hist_data->fields[key_idx]->offset = key_offset; 4292 4293 hist_data->key_size += key_size; 4294 4295 if (hist_data->key_size > HIST_KEY_SIZE_MAX) { 4296 ret = -EINVAL; 4297 goto out; 4298 } 4299 4300 hist_data->n_keys++; 4301 hist_data->n_fields++; 4302 4303 if (WARN_ON(hist_data->n_keys > TRACING_MAP_KEYS_MAX)) 4304 return -EINVAL; 4305 4306 ret = key_size; 4307 out: 4308 return ret; 4309 } 4310 4311 static int create_key_fields(struct hist_trigger_data *hist_data, 4312 struct trace_event_file *file) 4313 { 4314 unsigned int i, key_offset = 0, n_vals = hist_data->n_vals; 4315 char *fields_str, *field_str; 4316 int ret = -EINVAL; 4317 4318 fields_str = hist_data->attrs->keys_str; 4319 if (!fields_str) 4320 goto out; 4321 4322 for (i = n_vals; i < n_vals + TRACING_MAP_KEYS_MAX; i++) { 4323 field_str = strsep(&fields_str, ","); 4324 if (!field_str) 4325 break; 4326 ret = create_key_field(hist_data, i, key_offset, 4327 file, field_str); 4328 if (ret < 0) 4329 goto out; 4330 key_offset += ret; 4331 } 4332 if (fields_str) { 4333 ret = -EINVAL; 4334 goto out; 4335 } 4336 ret = 0; 4337 out: 4338 return ret; 4339 } 4340 4341 static int create_var_fields(struct hist_trigger_data *hist_data, 4342 struct trace_event_file *file) 4343 { 4344 unsigned int i, j = hist_data->n_vals; 4345 int ret = 0; 4346 4347 unsigned int n_vars = hist_data->attrs->var_defs.n_vars; 4348 4349 for (i = 0; i < n_vars; i++) { 4350 char *var_name = hist_data->attrs->var_defs.name[i]; 4351 char *expr = hist_data->attrs->var_defs.expr[i]; 4352 4353 ret = create_var_field(hist_data, j++, file, var_name, expr); 4354 if (ret) 4355 goto out; 4356 } 4357 out: 4358 return ret; 4359 } 4360 4361 static void free_var_defs(struct hist_trigger_data *hist_data) 4362 { 4363 unsigned int i; 4364 4365 for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) { 4366 kfree(hist_data->attrs->var_defs.name[i]); 4367 kfree(hist_data->attrs->var_defs.expr[i]); 4368 } 4369 4370 hist_data->attrs->var_defs.n_vars = 0; 4371 } 4372 4373 static int parse_var_defs(struct hist_trigger_data *hist_data) 4374 { 4375 struct trace_array *tr = hist_data->event_file->tr; 4376 char *s, *str, *var_name, *field_str; 4377 unsigned int i, j, n_vars = 0; 4378 int ret = 0; 4379 4380 for (i = 0; i < hist_data->attrs->n_assignments; i++) { 4381 str = hist_data->attrs->assignment_str[i]; 4382 for (j = 0; j < TRACING_MAP_VARS_MAX; j++) { 4383 field_str = strsep(&str, ","); 4384 if (!field_str) 4385 break; 4386 4387 var_name = strsep(&field_str, "="); 4388 if (!var_name || !field_str) { 4389 hist_err(tr, HIST_ERR_MALFORMED_ASSIGNMENT, 4390 errpos(var_name)); 4391 ret = -EINVAL; 4392 goto free; 4393 } 4394 4395 if (n_vars == TRACING_MAP_VARS_MAX) { 4396 hist_err(tr, HIST_ERR_TOO_MANY_VARS, errpos(var_name)); 4397 ret = -EINVAL; 4398 goto free; 4399 } 4400 4401 s = kstrdup(var_name, GFP_KERNEL); 4402 if (!s) { 4403 ret = -ENOMEM; 4404 goto free; 4405 } 4406 hist_data->attrs->var_defs.name[n_vars] = s; 4407 4408 s = kstrdup(field_str, GFP_KERNEL); 4409 if (!s) { 4410 ret = -ENOMEM; 4411 goto free; 4412 } 4413 hist_data->attrs->var_defs.expr[n_vars++] = s; 4414 4415 hist_data->attrs->var_defs.n_vars = n_vars; 4416 } 4417 } 4418 4419 return ret; 4420 free: 4421 free_var_defs(hist_data); 4422 4423 return ret; 4424 } 4425 4426 static int create_hist_fields(struct hist_trigger_data *hist_data, 4427 struct trace_event_file *file) 4428 { 4429 int ret; 4430 4431 ret = parse_var_defs(hist_data); 4432 if (ret) 4433 goto out; 4434 4435 ret = create_val_fields(hist_data, file); 4436 if (ret) 4437 goto out; 4438 4439 ret = create_var_fields(hist_data, file); 4440 if (ret) 4441 goto out; 4442 4443 ret = create_key_fields(hist_data, file); 4444 if (ret) 4445 goto out; 4446 out: 4447 free_var_defs(hist_data); 4448 4449 return ret; 4450 } 4451 4452 static int is_descending(struct trace_array *tr, const char *str) 4453 { 4454 if (!str) 4455 return 0; 4456 4457 if (strcmp(str, "descending") == 0) 4458 return 1; 4459 4460 if (strcmp(str, "ascending") == 0) 4461 return 0; 4462 4463 hist_err(tr, HIST_ERR_INVALID_SORT_MODIFIER, errpos((char *)str)); 4464 4465 return -EINVAL; 4466 } 4467 4468 static int create_sort_keys(struct hist_trigger_data *hist_data) 4469 { 4470 struct trace_array *tr = hist_data->event_file->tr; 4471 char *fields_str = hist_data->attrs->sort_key_str; 4472 struct tracing_map_sort_key *sort_key; 4473 int descending, ret = 0; 4474 unsigned int i, j, k; 4475 4476 hist_data->n_sort_keys = 1; /* we always have at least one, hitcount */ 4477 4478 if (!fields_str) 4479 goto out; 4480 4481 for (i = 0; i < TRACING_MAP_SORT_KEYS_MAX; i++) { 4482 struct hist_field *hist_field; 4483 char *field_str, *field_name; 4484 const char *test_name; 4485 4486 sort_key = &hist_data->sort_keys[i]; 4487 4488 field_str = strsep(&fields_str, ","); 4489 if (!field_str) 4490 break; 4491 4492 if (!*field_str) { 4493 ret = -EINVAL; 4494 hist_err(tr, HIST_ERR_EMPTY_SORT_FIELD, errpos("sort=")); 4495 break; 4496 } 4497 4498 if ((i == TRACING_MAP_SORT_KEYS_MAX - 1) && fields_str) { 4499 hist_err(tr, HIST_ERR_TOO_MANY_SORT_FIELDS, errpos("sort=")); 4500 ret = -EINVAL; 4501 break; 4502 } 4503 4504 field_name = strsep(&field_str, "."); 4505 if (!field_name || !*field_name) { 4506 ret = -EINVAL; 4507 hist_err(tr, HIST_ERR_EMPTY_SORT_FIELD, errpos("sort=")); 4508 break; 4509 } 4510 4511 if (strcmp(field_name, "hitcount") == 0) { 4512 descending = is_descending(tr, field_str); 4513 if (descending < 0) { 4514 ret = descending; 4515 break; 4516 } 4517 sort_key->descending = descending; 4518 continue; 4519 } 4520 4521 for (j = 1, k = 1; j < hist_data->n_fields; j++) { 4522 unsigned int idx; 4523 4524 hist_field = hist_data->fields[j]; 4525 if (hist_field->flags & HIST_FIELD_FL_VAR) 4526 continue; 4527 4528 idx = k++; 4529 4530 test_name = hist_field_name(hist_field, 0); 4531 4532 if (strcmp(field_name, test_name) == 0) { 4533 sort_key->field_idx = idx; 4534 descending = is_descending(tr, field_str); 4535 if (descending < 0) { 4536 ret = descending; 4537 goto out; 4538 } 4539 sort_key->descending = descending; 4540 break; 4541 } 4542 } 4543 if (j == hist_data->n_fields) { 4544 ret = -EINVAL; 4545 hist_err(tr, HIST_ERR_INVALID_SORT_FIELD, errpos(field_name)); 4546 break; 4547 } 4548 } 4549 4550 hist_data->n_sort_keys = i; 4551 out: 4552 return ret; 4553 } 4554 4555 static void destroy_actions(struct hist_trigger_data *hist_data) 4556 { 4557 unsigned int i; 4558 4559 for (i = 0; i < hist_data->n_actions; i++) { 4560 struct action_data *data = hist_data->actions[i]; 4561 4562 if (data->handler == HANDLER_ONMATCH) 4563 onmatch_destroy(data); 4564 else if (data->handler == HANDLER_ONMAX || 4565 data->handler == HANDLER_ONCHANGE) 4566 track_data_destroy(hist_data, data); 4567 else 4568 kfree(data); 4569 } 4570 } 4571 4572 static int parse_actions(struct hist_trigger_data *hist_data) 4573 { 4574 struct trace_array *tr = hist_data->event_file->tr; 4575 struct action_data *data; 4576 unsigned int i; 4577 int ret = 0; 4578 char *str; 4579 int len; 4580 4581 for (i = 0; i < hist_data->attrs->n_actions; i++) { 4582 str = hist_data->attrs->action_str[i]; 4583 4584 if ((len = str_has_prefix(str, "onmatch("))) { 4585 char *action_str = str + len; 4586 4587 data = onmatch_parse(tr, action_str); 4588 if (IS_ERR(data)) { 4589 ret = PTR_ERR(data); 4590 break; 4591 } 4592 } else if ((len = str_has_prefix(str, "onmax("))) { 4593 char *action_str = str + len; 4594 4595 data = track_data_parse(hist_data, action_str, 4596 HANDLER_ONMAX); 4597 if (IS_ERR(data)) { 4598 ret = PTR_ERR(data); 4599 break; 4600 } 4601 } else if ((len = str_has_prefix(str, "onchange("))) { 4602 char *action_str = str + len; 4603 4604 data = track_data_parse(hist_data, action_str, 4605 HANDLER_ONCHANGE); 4606 if (IS_ERR(data)) { 4607 ret = PTR_ERR(data); 4608 break; 4609 } 4610 } else { 4611 ret = -EINVAL; 4612 break; 4613 } 4614 4615 hist_data->actions[hist_data->n_actions++] = data; 4616 } 4617 4618 return ret; 4619 } 4620 4621 static int create_actions(struct hist_trigger_data *hist_data) 4622 { 4623 struct action_data *data; 4624 unsigned int i; 4625 int ret = 0; 4626 4627 for (i = 0; i < hist_data->attrs->n_actions; i++) { 4628 data = hist_data->actions[i]; 4629 4630 if (data->handler == HANDLER_ONMATCH) { 4631 ret = onmatch_create(hist_data, data); 4632 if (ret) 4633 break; 4634 } else if (data->handler == HANDLER_ONMAX || 4635 data->handler == HANDLER_ONCHANGE) { 4636 ret = track_data_create(hist_data, data); 4637 if (ret) 4638 break; 4639 } else { 4640 ret = -EINVAL; 4641 break; 4642 } 4643 } 4644 4645 return ret; 4646 } 4647 4648 static void print_actions(struct seq_file *m, 4649 struct hist_trigger_data *hist_data, 4650 struct tracing_map_elt *elt) 4651 { 4652 unsigned int i; 4653 4654 for (i = 0; i < hist_data->n_actions; i++) { 4655 struct action_data *data = hist_data->actions[i]; 4656 4657 if (data->action == ACTION_SNAPSHOT) 4658 continue; 4659 4660 if (data->handler == HANDLER_ONMAX || 4661 data->handler == HANDLER_ONCHANGE) 4662 track_data_print(m, hist_data, elt, data); 4663 } 4664 } 4665 4666 static void print_action_spec(struct seq_file *m, 4667 struct hist_trigger_data *hist_data, 4668 struct action_data *data) 4669 { 4670 unsigned int i; 4671 4672 if (data->action == ACTION_SAVE) { 4673 for (i = 0; i < hist_data->n_save_vars; i++) { 4674 seq_printf(m, "%s", hist_data->save_vars[i]->var->var.name); 4675 if (i < hist_data->n_save_vars - 1) 4676 seq_puts(m, ","); 4677 } 4678 } else if (data->action == ACTION_TRACE) { 4679 if (data->use_trace_keyword) 4680 seq_printf(m, "%s", data->synth_event_name); 4681 for (i = 0; i < data->n_params; i++) { 4682 if (i || data->use_trace_keyword) 4683 seq_puts(m, ","); 4684 seq_printf(m, "%s", data->params[i]); 4685 } 4686 } 4687 } 4688 4689 static void print_track_data_spec(struct seq_file *m, 4690 struct hist_trigger_data *hist_data, 4691 struct action_data *data) 4692 { 4693 if (data->handler == HANDLER_ONMAX) 4694 seq_puts(m, ":onmax("); 4695 else if (data->handler == HANDLER_ONCHANGE) 4696 seq_puts(m, ":onchange("); 4697 seq_printf(m, "%s", data->track_data.var_str); 4698 seq_printf(m, ").%s(", data->action_name); 4699 4700 print_action_spec(m, hist_data, data); 4701 4702 seq_puts(m, ")"); 4703 } 4704 4705 static void print_onmatch_spec(struct seq_file *m, 4706 struct hist_trigger_data *hist_data, 4707 struct action_data *data) 4708 { 4709 seq_printf(m, ":onmatch(%s.%s).", data->match_data.event_system, 4710 data->match_data.event); 4711 4712 seq_printf(m, "%s(", data->action_name); 4713 4714 print_action_spec(m, hist_data, data); 4715 4716 seq_puts(m, ")"); 4717 } 4718 4719 static bool actions_match(struct hist_trigger_data *hist_data, 4720 struct hist_trigger_data *hist_data_test) 4721 { 4722 unsigned int i, j; 4723 4724 if (hist_data->n_actions != hist_data_test->n_actions) 4725 return false; 4726 4727 for (i = 0; i < hist_data->n_actions; i++) { 4728 struct action_data *data = hist_data->actions[i]; 4729 struct action_data *data_test = hist_data_test->actions[i]; 4730 char *action_name, *action_name_test; 4731 4732 if (data->handler != data_test->handler) 4733 return false; 4734 if (data->action != data_test->action) 4735 return false; 4736 4737 if (data->n_params != data_test->n_params) 4738 return false; 4739 4740 for (j = 0; j < data->n_params; j++) { 4741 if (strcmp(data->params[j], data_test->params[j]) != 0) 4742 return false; 4743 } 4744 4745 if (data->use_trace_keyword) 4746 action_name = data->synth_event_name; 4747 else 4748 action_name = data->action_name; 4749 4750 if (data_test->use_trace_keyword) 4751 action_name_test = data_test->synth_event_name; 4752 else 4753 action_name_test = data_test->action_name; 4754 4755 if (strcmp(action_name, action_name_test) != 0) 4756 return false; 4757 4758 if (data->handler == HANDLER_ONMATCH) { 4759 if (strcmp(data->match_data.event_system, 4760 data_test->match_data.event_system) != 0) 4761 return false; 4762 if (strcmp(data->match_data.event, 4763 data_test->match_data.event) != 0) 4764 return false; 4765 } else if (data->handler == HANDLER_ONMAX || 4766 data->handler == HANDLER_ONCHANGE) { 4767 if (strcmp(data->track_data.var_str, 4768 data_test->track_data.var_str) != 0) 4769 return false; 4770 } 4771 } 4772 4773 return true; 4774 } 4775 4776 4777 static void print_actions_spec(struct seq_file *m, 4778 struct hist_trigger_data *hist_data) 4779 { 4780 unsigned int i; 4781 4782 for (i = 0; i < hist_data->n_actions; i++) { 4783 struct action_data *data = hist_data->actions[i]; 4784 4785 if (data->handler == HANDLER_ONMATCH) 4786 print_onmatch_spec(m, hist_data, data); 4787 else if (data->handler == HANDLER_ONMAX || 4788 data->handler == HANDLER_ONCHANGE) 4789 print_track_data_spec(m, hist_data, data); 4790 } 4791 } 4792 4793 static void destroy_field_var_hists(struct hist_trigger_data *hist_data) 4794 { 4795 unsigned int i; 4796 4797 for (i = 0; i < hist_data->n_field_var_hists; i++) { 4798 kfree(hist_data->field_var_hists[i]->cmd); 4799 kfree(hist_data->field_var_hists[i]); 4800 } 4801 } 4802 4803 static void destroy_hist_data(struct hist_trigger_data *hist_data) 4804 { 4805 if (!hist_data) 4806 return; 4807 4808 destroy_hist_trigger_attrs(hist_data->attrs); 4809 destroy_hist_fields(hist_data); 4810 tracing_map_destroy(hist_data->map); 4811 4812 destroy_actions(hist_data); 4813 destroy_field_vars(hist_data); 4814 destroy_field_var_hists(hist_data); 4815 4816 kfree(hist_data); 4817 } 4818 4819 static int create_tracing_map_fields(struct hist_trigger_data *hist_data) 4820 { 4821 struct tracing_map *map = hist_data->map; 4822 struct ftrace_event_field *field; 4823 struct hist_field *hist_field; 4824 int i, idx = 0; 4825 4826 for_each_hist_field(i, hist_data) { 4827 hist_field = hist_data->fields[i]; 4828 if (hist_field->flags & HIST_FIELD_FL_KEY) { 4829 tracing_map_cmp_fn_t cmp_fn; 4830 4831 field = hist_field->field; 4832 4833 if (hist_field->flags & HIST_FIELD_FL_STACKTRACE) 4834 cmp_fn = tracing_map_cmp_none; 4835 else if (!field) 4836 cmp_fn = tracing_map_cmp_num(hist_field->size, 4837 hist_field->is_signed); 4838 else if (is_string_field(field)) 4839 cmp_fn = tracing_map_cmp_string; 4840 else 4841 cmp_fn = tracing_map_cmp_num(field->size, 4842 field->is_signed); 4843 idx = tracing_map_add_key_field(map, 4844 hist_field->offset, 4845 cmp_fn); 4846 } else if (!(hist_field->flags & HIST_FIELD_FL_VAR)) 4847 idx = tracing_map_add_sum_field(map); 4848 4849 if (idx < 0) 4850 return idx; 4851 4852 if (hist_field->flags & HIST_FIELD_FL_VAR) { 4853 idx = tracing_map_add_var(map); 4854 if (idx < 0) 4855 return idx; 4856 hist_field->var.idx = idx; 4857 hist_field->var.hist_data = hist_data; 4858 } 4859 } 4860 4861 return 0; 4862 } 4863 4864 static struct hist_trigger_data * 4865 create_hist_data(unsigned int map_bits, 4866 struct hist_trigger_attrs *attrs, 4867 struct trace_event_file *file, 4868 bool remove) 4869 { 4870 const struct tracing_map_ops *map_ops = NULL; 4871 struct hist_trigger_data *hist_data; 4872 int ret = 0; 4873 4874 hist_data = kzalloc(sizeof(*hist_data), GFP_KERNEL); 4875 if (!hist_data) 4876 return ERR_PTR(-ENOMEM); 4877 4878 hist_data->attrs = attrs; 4879 hist_data->remove = remove; 4880 hist_data->event_file = file; 4881 4882 ret = parse_actions(hist_data); 4883 if (ret) 4884 goto free; 4885 4886 ret = create_hist_fields(hist_data, file); 4887 if (ret) 4888 goto free; 4889 4890 ret = create_sort_keys(hist_data); 4891 if (ret) 4892 goto free; 4893 4894 map_ops = &hist_trigger_elt_data_ops; 4895 4896 hist_data->map = tracing_map_create(map_bits, hist_data->key_size, 4897 map_ops, hist_data); 4898 if (IS_ERR(hist_data->map)) { 4899 ret = PTR_ERR(hist_data->map); 4900 hist_data->map = NULL; 4901 goto free; 4902 } 4903 4904 ret = create_tracing_map_fields(hist_data); 4905 if (ret) 4906 goto free; 4907 out: 4908 return hist_data; 4909 free: 4910 hist_data->attrs = NULL; 4911 4912 destroy_hist_data(hist_data); 4913 4914 hist_data = ERR_PTR(ret); 4915 4916 goto out; 4917 } 4918 4919 static void hist_trigger_elt_update(struct hist_trigger_data *hist_data, 4920 struct tracing_map_elt *elt, 4921 struct trace_buffer *buffer, void *rec, 4922 struct ring_buffer_event *rbe, 4923 u64 *var_ref_vals) 4924 { 4925 struct hist_elt_data *elt_data; 4926 struct hist_field *hist_field; 4927 unsigned int i, var_idx; 4928 u64 hist_val; 4929 4930 elt_data = elt->private_data; 4931 elt_data->var_ref_vals = var_ref_vals; 4932 4933 for_each_hist_val_field(i, hist_data) { 4934 hist_field = hist_data->fields[i]; 4935 hist_val = hist_field->fn(hist_field, elt, buffer, rbe, rec); 4936 if (hist_field->flags & HIST_FIELD_FL_VAR) { 4937 var_idx = hist_field->var.idx; 4938 4939 if (hist_field->flags & HIST_FIELD_FL_STRING) { 4940 unsigned int str_start, var_str_idx, idx; 4941 char *str, *val_str; 4942 unsigned int size; 4943 4944 str_start = hist_data->n_field_var_str + 4945 hist_data->n_save_var_str; 4946 var_str_idx = hist_field->var_str_idx; 4947 idx = str_start + var_str_idx; 4948 4949 str = elt_data->field_var_str[idx]; 4950 val_str = (char *)(uintptr_t)hist_val; 4951 4952 size = min(hist_field->size, STR_VAR_LEN_MAX); 4953 strscpy(str, val_str, size); 4954 4955 hist_val = (u64)(uintptr_t)str; 4956 } 4957 tracing_map_set_var(elt, var_idx, hist_val); 4958 continue; 4959 } 4960 tracing_map_update_sum(elt, i, hist_val); 4961 } 4962 4963 for_each_hist_key_field(i, hist_data) { 4964 hist_field = hist_data->fields[i]; 4965 if (hist_field->flags & HIST_FIELD_FL_VAR) { 4966 hist_val = hist_field->fn(hist_field, elt, buffer, rbe, rec); 4967 var_idx = hist_field->var.idx; 4968 tracing_map_set_var(elt, var_idx, hist_val); 4969 } 4970 } 4971 4972 update_field_vars(hist_data, elt, buffer, rbe, rec); 4973 } 4974 4975 static inline void add_to_key(char *compound_key, void *key, 4976 struct hist_field *key_field, void *rec) 4977 { 4978 size_t size = key_field->size; 4979 4980 if (key_field->flags & HIST_FIELD_FL_STRING) { 4981 struct ftrace_event_field *field; 4982 4983 field = key_field->field; 4984 if (field->filter_type == FILTER_DYN_STRING || 4985 field->filter_type == FILTER_RDYN_STRING) 4986 size = *(u32 *)(rec + field->offset) >> 16; 4987 else if (field->filter_type == FILTER_STATIC_STRING) 4988 size = field->size; 4989 4990 /* ensure NULL-termination */ 4991 if (size > key_field->size - 1) 4992 size = key_field->size - 1; 4993 4994 strncpy(compound_key + key_field->offset, (char *)key, size); 4995 } else 4996 memcpy(compound_key + key_field->offset, key, size); 4997 } 4998 4999 static void 5000 hist_trigger_actions(struct hist_trigger_data *hist_data, 5001 struct tracing_map_elt *elt, 5002 struct trace_buffer *buffer, void *rec, 5003 struct ring_buffer_event *rbe, void *key, 5004 u64 *var_ref_vals) 5005 { 5006 struct action_data *data; 5007 unsigned int i; 5008 5009 for (i = 0; i < hist_data->n_actions; i++) { 5010 data = hist_data->actions[i]; 5011 data->fn(hist_data, elt, buffer, rec, rbe, key, data, var_ref_vals); 5012 } 5013 } 5014 5015 static void event_hist_trigger(struct event_trigger_data *data, 5016 struct trace_buffer *buffer, void *rec, 5017 struct ring_buffer_event *rbe) 5018 { 5019 struct hist_trigger_data *hist_data = data->private_data; 5020 bool use_compound_key = (hist_data->n_keys > 1); 5021 unsigned long entries[HIST_STACKTRACE_DEPTH]; 5022 u64 var_ref_vals[TRACING_MAP_VARS_MAX]; 5023 char compound_key[HIST_KEY_SIZE_MAX]; 5024 struct tracing_map_elt *elt = NULL; 5025 struct hist_field *key_field; 5026 u64 field_contents; 5027 void *key = NULL; 5028 unsigned int i; 5029 5030 memset(compound_key, 0, hist_data->key_size); 5031 5032 for_each_hist_key_field(i, hist_data) { 5033 key_field = hist_data->fields[i]; 5034 5035 if (key_field->flags & HIST_FIELD_FL_STACKTRACE) { 5036 memset(entries, 0, HIST_STACKTRACE_SIZE); 5037 stack_trace_save(entries, HIST_STACKTRACE_DEPTH, 5038 HIST_STACKTRACE_SKIP); 5039 key = entries; 5040 } else { 5041 field_contents = key_field->fn(key_field, elt, buffer, rbe, rec); 5042 if (key_field->flags & HIST_FIELD_FL_STRING) { 5043 key = (void *)(unsigned long)field_contents; 5044 use_compound_key = true; 5045 } else 5046 key = (void *)&field_contents; 5047 } 5048 5049 if (use_compound_key) 5050 add_to_key(compound_key, key, key_field, rec); 5051 } 5052 5053 if (use_compound_key) 5054 key = compound_key; 5055 5056 if (hist_data->n_var_refs && 5057 !resolve_var_refs(hist_data, key, var_ref_vals, false)) 5058 return; 5059 5060 elt = tracing_map_insert(hist_data->map, key); 5061 if (!elt) 5062 return; 5063 5064 hist_trigger_elt_update(hist_data, elt, buffer, rec, rbe, var_ref_vals); 5065 5066 if (resolve_var_refs(hist_data, key, var_ref_vals, true)) 5067 hist_trigger_actions(hist_data, elt, buffer, rec, rbe, key, var_ref_vals); 5068 } 5069 5070 static void hist_trigger_stacktrace_print(struct seq_file *m, 5071 unsigned long *stacktrace_entries, 5072 unsigned int max_entries) 5073 { 5074 unsigned int spaces = 8; 5075 unsigned int i; 5076 5077 for (i = 0; i < max_entries; i++) { 5078 if (!stacktrace_entries[i]) 5079 return; 5080 5081 seq_printf(m, "%*c", 1 + spaces, ' '); 5082 seq_printf(m, "%pS\n", (void*)stacktrace_entries[i]); 5083 } 5084 } 5085 5086 static void hist_trigger_print_key(struct seq_file *m, 5087 struct hist_trigger_data *hist_data, 5088 void *key, 5089 struct tracing_map_elt *elt) 5090 { 5091 struct hist_field *key_field; 5092 bool multiline = false; 5093 const char *field_name; 5094 unsigned int i; 5095 u64 uval; 5096 5097 seq_puts(m, "{ "); 5098 5099 for_each_hist_key_field(i, hist_data) { 5100 key_field = hist_data->fields[i]; 5101 5102 if (i > hist_data->n_vals) 5103 seq_puts(m, ", "); 5104 5105 field_name = hist_field_name(key_field, 0); 5106 5107 if (key_field->flags & HIST_FIELD_FL_HEX) { 5108 uval = *(u64 *)(key + key_field->offset); 5109 seq_printf(m, "%s: %llx", field_name, uval); 5110 } else if (key_field->flags & HIST_FIELD_FL_SYM) { 5111 uval = *(u64 *)(key + key_field->offset); 5112 seq_printf(m, "%s: [%llx] %-45ps", field_name, 5113 uval, (void *)(uintptr_t)uval); 5114 } else if (key_field->flags & HIST_FIELD_FL_SYM_OFFSET) { 5115 uval = *(u64 *)(key + key_field->offset); 5116 seq_printf(m, "%s: [%llx] %-55pS", field_name, 5117 uval, (void *)(uintptr_t)uval); 5118 } else if (key_field->flags & HIST_FIELD_FL_EXECNAME) { 5119 struct hist_elt_data *elt_data = elt->private_data; 5120 char *comm; 5121 5122 if (WARN_ON_ONCE(!elt_data)) 5123 return; 5124 5125 comm = elt_data->comm; 5126 5127 uval = *(u64 *)(key + key_field->offset); 5128 seq_printf(m, "%s: %-16s[%10llu]", field_name, 5129 comm, uval); 5130 } else if (key_field->flags & HIST_FIELD_FL_SYSCALL) { 5131 const char *syscall_name; 5132 5133 uval = *(u64 *)(key + key_field->offset); 5134 syscall_name = get_syscall_name(uval); 5135 if (!syscall_name) 5136 syscall_name = "unknown_syscall"; 5137 5138 seq_printf(m, "%s: %-30s[%3llu]", field_name, 5139 syscall_name, uval); 5140 } else if (key_field->flags & HIST_FIELD_FL_STACKTRACE) { 5141 seq_puts(m, "stacktrace:\n"); 5142 hist_trigger_stacktrace_print(m, 5143 key + key_field->offset, 5144 HIST_STACKTRACE_DEPTH); 5145 multiline = true; 5146 } else if (key_field->flags & HIST_FIELD_FL_LOG2) { 5147 seq_printf(m, "%s: ~ 2^%-2llu", field_name, 5148 *(u64 *)(key + key_field->offset)); 5149 } else if (key_field->flags & HIST_FIELD_FL_BUCKET) { 5150 unsigned long buckets = key_field->buckets; 5151 uval = *(u64 *)(key + key_field->offset); 5152 seq_printf(m, "%s: ~ %llu-%llu", field_name, 5153 uval, uval + buckets -1); 5154 } else if (key_field->flags & HIST_FIELD_FL_STRING) { 5155 seq_printf(m, "%s: %-50s", field_name, 5156 (char *)(key + key_field->offset)); 5157 } else { 5158 uval = *(u64 *)(key + key_field->offset); 5159 seq_printf(m, "%s: %10llu", field_name, uval); 5160 } 5161 } 5162 5163 if (!multiline) 5164 seq_puts(m, " "); 5165 5166 seq_puts(m, "}"); 5167 } 5168 5169 static void hist_trigger_entry_print(struct seq_file *m, 5170 struct hist_trigger_data *hist_data, 5171 void *key, 5172 struct tracing_map_elt *elt) 5173 { 5174 const char *field_name; 5175 unsigned int i; 5176 5177 hist_trigger_print_key(m, hist_data, key, elt); 5178 5179 seq_printf(m, " hitcount: %10llu", 5180 tracing_map_read_sum(elt, HITCOUNT_IDX)); 5181 5182 for (i = 1; i < hist_data->n_vals; i++) { 5183 field_name = hist_field_name(hist_data->fields[i], 0); 5184 5185 if (hist_data->fields[i]->flags & HIST_FIELD_FL_VAR || 5186 hist_data->fields[i]->flags & HIST_FIELD_FL_EXPR) 5187 continue; 5188 5189 if (hist_data->fields[i]->flags & HIST_FIELD_FL_HEX) { 5190 seq_printf(m, " %s: %10llx", field_name, 5191 tracing_map_read_sum(elt, i)); 5192 } else { 5193 seq_printf(m, " %s: %10llu", field_name, 5194 tracing_map_read_sum(elt, i)); 5195 } 5196 } 5197 5198 print_actions(m, hist_data, elt); 5199 5200 seq_puts(m, "\n"); 5201 } 5202 5203 static int print_entries(struct seq_file *m, 5204 struct hist_trigger_data *hist_data) 5205 { 5206 struct tracing_map_sort_entry **sort_entries = NULL; 5207 struct tracing_map *map = hist_data->map; 5208 int i, n_entries; 5209 5210 n_entries = tracing_map_sort_entries(map, hist_data->sort_keys, 5211 hist_data->n_sort_keys, 5212 &sort_entries); 5213 if (n_entries < 0) 5214 return n_entries; 5215 5216 for (i = 0; i < n_entries; i++) 5217 hist_trigger_entry_print(m, hist_data, 5218 sort_entries[i]->key, 5219 sort_entries[i]->elt); 5220 5221 tracing_map_destroy_sort_entries(sort_entries, n_entries); 5222 5223 return n_entries; 5224 } 5225 5226 static void hist_trigger_show(struct seq_file *m, 5227 struct event_trigger_data *data, int n) 5228 { 5229 struct hist_trigger_data *hist_data; 5230 int n_entries; 5231 5232 if (n > 0) 5233 seq_puts(m, "\n\n"); 5234 5235 seq_puts(m, "# event histogram\n#\n# trigger info: "); 5236 data->ops->print(m, data->ops, data); 5237 seq_puts(m, "#\n\n"); 5238 5239 hist_data = data->private_data; 5240 n_entries = print_entries(m, hist_data); 5241 if (n_entries < 0) 5242 n_entries = 0; 5243 5244 track_data_snapshot_print(m, hist_data); 5245 5246 seq_printf(m, "\nTotals:\n Hits: %llu\n Entries: %u\n Dropped: %llu\n", 5247 (u64)atomic64_read(&hist_data->map->hits), 5248 n_entries, (u64)atomic64_read(&hist_data->map->drops)); 5249 } 5250 5251 static int hist_show(struct seq_file *m, void *v) 5252 { 5253 struct event_trigger_data *data; 5254 struct trace_event_file *event_file; 5255 int n = 0, ret = 0; 5256 5257 mutex_lock(&event_mutex); 5258 5259 event_file = event_file_data(m->private); 5260 if (unlikely(!event_file)) { 5261 ret = -ENODEV; 5262 goto out_unlock; 5263 } 5264 5265 list_for_each_entry(data, &event_file->triggers, list) { 5266 if (data->cmd_ops->trigger_type == ETT_EVENT_HIST) 5267 hist_trigger_show(m, data, n++); 5268 } 5269 5270 out_unlock: 5271 mutex_unlock(&event_mutex); 5272 5273 return ret; 5274 } 5275 5276 static int event_hist_open(struct inode *inode, struct file *file) 5277 { 5278 int ret; 5279 5280 ret = security_locked_down(LOCKDOWN_TRACEFS); 5281 if (ret) 5282 return ret; 5283 5284 return single_open(file, hist_show, file); 5285 } 5286 5287 const struct file_operations event_hist_fops = { 5288 .open = event_hist_open, 5289 .read = seq_read, 5290 .llseek = seq_lseek, 5291 .release = single_release, 5292 }; 5293 5294 #ifdef CONFIG_HIST_TRIGGERS_DEBUG 5295 static void hist_field_debug_show_flags(struct seq_file *m, 5296 unsigned long flags) 5297 { 5298 seq_puts(m, " flags:\n"); 5299 5300 if (flags & HIST_FIELD_FL_KEY) 5301 seq_puts(m, " HIST_FIELD_FL_KEY\n"); 5302 else if (flags & HIST_FIELD_FL_HITCOUNT) 5303 seq_puts(m, " VAL: HIST_FIELD_FL_HITCOUNT\n"); 5304 else if (flags & HIST_FIELD_FL_VAR) 5305 seq_puts(m, " HIST_FIELD_FL_VAR\n"); 5306 else if (flags & HIST_FIELD_FL_VAR_REF) 5307 seq_puts(m, " HIST_FIELD_FL_VAR_REF\n"); 5308 else 5309 seq_puts(m, " VAL: normal u64 value\n"); 5310 5311 if (flags & HIST_FIELD_FL_ALIAS) 5312 seq_puts(m, " HIST_FIELD_FL_ALIAS\n"); 5313 else if (flags & HIST_FIELD_FL_CONST) 5314 seq_puts(m, " HIST_FIELD_FL_CONST\n"); 5315 } 5316 5317 static int hist_field_debug_show(struct seq_file *m, 5318 struct hist_field *field, unsigned long flags) 5319 { 5320 if ((field->flags & flags) != flags) { 5321 seq_printf(m, "ERROR: bad flags - %lx\n", flags); 5322 return -EINVAL; 5323 } 5324 5325 hist_field_debug_show_flags(m, field->flags); 5326 if (field->field) 5327 seq_printf(m, " ftrace_event_field name: %s\n", 5328 field->field->name); 5329 5330 if (field->flags & HIST_FIELD_FL_VAR) { 5331 seq_printf(m, " var.name: %s\n", field->var.name); 5332 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n", 5333 field->var.idx); 5334 } 5335 5336 if (field->flags & HIST_FIELD_FL_CONST) 5337 seq_printf(m, " constant: %llu\n", field->constant); 5338 5339 if (field->flags & HIST_FIELD_FL_ALIAS) 5340 seq_printf(m, " var_ref_idx (into hist_data->var_refs[]): %u\n", 5341 field->var_ref_idx); 5342 5343 if (field->flags & HIST_FIELD_FL_VAR_REF) { 5344 seq_printf(m, " name: %s\n", field->name); 5345 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n", 5346 field->var.idx); 5347 seq_printf(m, " var.hist_data: %p\n", field->var.hist_data); 5348 seq_printf(m, " var_ref_idx (into hist_data->var_refs[]): %u\n", 5349 field->var_ref_idx); 5350 if (field->system) 5351 seq_printf(m, " system: %s\n", field->system); 5352 if (field->event_name) 5353 seq_printf(m, " event_name: %s\n", field->event_name); 5354 } 5355 5356 seq_printf(m, " type: %s\n", field->type); 5357 seq_printf(m, " size: %u\n", field->size); 5358 seq_printf(m, " is_signed: %u\n", field->is_signed); 5359 5360 return 0; 5361 } 5362 5363 static int field_var_debug_show(struct seq_file *m, 5364 struct field_var *field_var, unsigned int i, 5365 bool save_vars) 5366 { 5367 const char *vars_name = save_vars ? "save_vars" : "field_vars"; 5368 struct hist_field *field; 5369 int ret = 0; 5370 5371 seq_printf(m, "\n hist_data->%s[%d]:\n", vars_name, i); 5372 5373 field = field_var->var; 5374 5375 seq_printf(m, "\n %s[%d].var:\n", vars_name, i); 5376 5377 hist_field_debug_show_flags(m, field->flags); 5378 seq_printf(m, " var.name: %s\n", field->var.name); 5379 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n", 5380 field->var.idx); 5381 5382 field = field_var->val; 5383 5384 seq_printf(m, "\n %s[%d].val:\n", vars_name, i); 5385 if (field->field) 5386 seq_printf(m, " ftrace_event_field name: %s\n", 5387 field->field->name); 5388 else { 5389 ret = -EINVAL; 5390 goto out; 5391 } 5392 5393 seq_printf(m, " type: %s\n", field->type); 5394 seq_printf(m, " size: %u\n", field->size); 5395 seq_printf(m, " is_signed: %u\n", field->is_signed); 5396 out: 5397 return ret; 5398 } 5399 5400 static int hist_action_debug_show(struct seq_file *m, 5401 struct action_data *data, int i) 5402 { 5403 int ret = 0; 5404 5405 if (data->handler == HANDLER_ONMAX || 5406 data->handler == HANDLER_ONCHANGE) { 5407 seq_printf(m, "\n hist_data->actions[%d].track_data.var_ref:\n", i); 5408 ret = hist_field_debug_show(m, data->track_data.var_ref, 5409 HIST_FIELD_FL_VAR_REF); 5410 if (ret) 5411 goto out; 5412 5413 seq_printf(m, "\n hist_data->actions[%d].track_data.track_var:\n", i); 5414 ret = hist_field_debug_show(m, data->track_data.track_var, 5415 HIST_FIELD_FL_VAR); 5416 if (ret) 5417 goto out; 5418 } 5419 5420 if (data->handler == HANDLER_ONMATCH) { 5421 seq_printf(m, "\n hist_data->actions[%d].match_data.event_system: %s\n", 5422 i, data->match_data.event_system); 5423 seq_printf(m, " hist_data->actions[%d].match_data.event: %s\n", 5424 i, data->match_data.event); 5425 } 5426 out: 5427 return ret; 5428 } 5429 5430 static int hist_actions_debug_show(struct seq_file *m, 5431 struct hist_trigger_data *hist_data) 5432 { 5433 int i, ret = 0; 5434 5435 if (hist_data->n_actions) 5436 seq_puts(m, "\n action tracking variables (for onmax()/onchange()/onmatch()):\n"); 5437 5438 for (i = 0; i < hist_data->n_actions; i++) { 5439 struct action_data *action = hist_data->actions[i]; 5440 5441 ret = hist_action_debug_show(m, action, i); 5442 if (ret) 5443 goto out; 5444 } 5445 5446 if (hist_data->n_save_vars) 5447 seq_puts(m, "\n save action variables (save() params):\n"); 5448 5449 for (i = 0; i < hist_data->n_save_vars; i++) { 5450 ret = field_var_debug_show(m, hist_data->save_vars[i], i, true); 5451 if (ret) 5452 goto out; 5453 } 5454 out: 5455 return ret; 5456 } 5457 5458 static void hist_trigger_debug_show(struct seq_file *m, 5459 struct event_trigger_data *data, int n) 5460 { 5461 struct hist_trigger_data *hist_data; 5462 int i, ret; 5463 5464 if (n > 0) 5465 seq_puts(m, "\n\n"); 5466 5467 seq_puts(m, "# event histogram\n#\n# trigger info: "); 5468 data->ops->print(m, data->ops, data); 5469 seq_puts(m, "#\n\n"); 5470 5471 hist_data = data->private_data; 5472 5473 seq_printf(m, "hist_data: %p\n\n", hist_data); 5474 seq_printf(m, " n_vals: %u\n", hist_data->n_vals); 5475 seq_printf(m, " n_keys: %u\n", hist_data->n_keys); 5476 seq_printf(m, " n_fields: %u\n", hist_data->n_fields); 5477 5478 seq_puts(m, "\n val fields:\n\n"); 5479 5480 seq_puts(m, " hist_data->fields[0]:\n"); 5481 ret = hist_field_debug_show(m, hist_data->fields[0], 5482 HIST_FIELD_FL_HITCOUNT); 5483 if (ret) 5484 return; 5485 5486 for (i = 1; i < hist_data->n_vals; i++) { 5487 seq_printf(m, "\n hist_data->fields[%d]:\n", i); 5488 ret = hist_field_debug_show(m, hist_data->fields[i], 0); 5489 if (ret) 5490 return; 5491 } 5492 5493 seq_puts(m, "\n key fields:\n"); 5494 5495 for (i = hist_data->n_vals; i < hist_data->n_fields; i++) { 5496 seq_printf(m, "\n hist_data->fields[%d]:\n", i); 5497 ret = hist_field_debug_show(m, hist_data->fields[i], 5498 HIST_FIELD_FL_KEY); 5499 if (ret) 5500 return; 5501 } 5502 5503 if (hist_data->n_var_refs) 5504 seq_puts(m, "\n variable reference fields:\n"); 5505 5506 for (i = 0; i < hist_data->n_var_refs; i++) { 5507 seq_printf(m, "\n hist_data->var_refs[%d]:\n", i); 5508 ret = hist_field_debug_show(m, hist_data->var_refs[i], 5509 HIST_FIELD_FL_VAR_REF); 5510 if (ret) 5511 return; 5512 } 5513 5514 if (hist_data->n_field_vars) 5515 seq_puts(m, "\n field variables:\n"); 5516 5517 for (i = 0; i < hist_data->n_field_vars; i++) { 5518 ret = field_var_debug_show(m, hist_data->field_vars[i], i, false); 5519 if (ret) 5520 return; 5521 } 5522 5523 ret = hist_actions_debug_show(m, hist_data); 5524 if (ret) 5525 return; 5526 } 5527 5528 static int hist_debug_show(struct seq_file *m, void *v) 5529 { 5530 struct event_trigger_data *data; 5531 struct trace_event_file *event_file; 5532 int n = 0, ret = 0; 5533 5534 mutex_lock(&event_mutex); 5535 5536 event_file = event_file_data(m->private); 5537 if (unlikely(!event_file)) { 5538 ret = -ENODEV; 5539 goto out_unlock; 5540 } 5541 5542 list_for_each_entry(data, &event_file->triggers, list) { 5543 if (data->cmd_ops->trigger_type == ETT_EVENT_HIST) 5544 hist_trigger_debug_show(m, data, n++); 5545 } 5546 5547 out_unlock: 5548 mutex_unlock(&event_mutex); 5549 5550 return ret; 5551 } 5552 5553 static int event_hist_debug_open(struct inode *inode, struct file *file) 5554 { 5555 int ret; 5556 5557 ret = security_locked_down(LOCKDOWN_TRACEFS); 5558 if (ret) 5559 return ret; 5560 5561 return single_open(file, hist_debug_show, file); 5562 } 5563 5564 const struct file_operations event_hist_debug_fops = { 5565 .open = event_hist_debug_open, 5566 .read = seq_read, 5567 .llseek = seq_lseek, 5568 .release = single_release, 5569 }; 5570 #endif 5571 5572 static void hist_field_print(struct seq_file *m, struct hist_field *hist_field) 5573 { 5574 const char *field_name = hist_field_name(hist_field, 0); 5575 5576 if (hist_field->var.name) 5577 seq_printf(m, "%s=", hist_field->var.name); 5578 5579 if (hist_field->flags & HIST_FIELD_FL_CPU) 5580 seq_puts(m, "common_cpu"); 5581 else if (hist_field->flags & HIST_FIELD_FL_CONST) 5582 seq_printf(m, "%llu", hist_field->constant); 5583 else if (field_name) { 5584 if (hist_field->flags & HIST_FIELD_FL_VAR_REF || 5585 hist_field->flags & HIST_FIELD_FL_ALIAS) 5586 seq_putc(m, '$'); 5587 seq_printf(m, "%s", field_name); 5588 } else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP) 5589 seq_puts(m, "common_timestamp"); 5590 5591 if (hist_field->flags) { 5592 if (!(hist_field->flags & HIST_FIELD_FL_VAR_REF) && 5593 !(hist_field->flags & HIST_FIELD_FL_EXPR)) { 5594 const char *flags = get_hist_field_flags(hist_field); 5595 5596 if (flags) 5597 seq_printf(m, ".%s", flags); 5598 } 5599 } 5600 if (hist_field->buckets) 5601 seq_printf(m, "=%ld", hist_field->buckets); 5602 } 5603 5604 static int event_hist_trigger_print(struct seq_file *m, 5605 struct event_trigger_ops *ops, 5606 struct event_trigger_data *data) 5607 { 5608 struct hist_trigger_data *hist_data = data->private_data; 5609 struct hist_field *field; 5610 bool have_var = false; 5611 unsigned int i; 5612 5613 seq_puts(m, "hist:"); 5614 5615 if (data->name) 5616 seq_printf(m, "%s:", data->name); 5617 5618 seq_puts(m, "keys="); 5619 5620 for_each_hist_key_field(i, hist_data) { 5621 field = hist_data->fields[i]; 5622 5623 if (i > hist_data->n_vals) 5624 seq_puts(m, ","); 5625 5626 if (field->flags & HIST_FIELD_FL_STACKTRACE) 5627 seq_puts(m, "stacktrace"); 5628 else 5629 hist_field_print(m, field); 5630 } 5631 5632 seq_puts(m, ":vals="); 5633 5634 for_each_hist_val_field(i, hist_data) { 5635 field = hist_data->fields[i]; 5636 if (field->flags & HIST_FIELD_FL_VAR) { 5637 have_var = true; 5638 continue; 5639 } 5640 5641 if (i == HITCOUNT_IDX) 5642 seq_puts(m, "hitcount"); 5643 else { 5644 seq_puts(m, ","); 5645 hist_field_print(m, field); 5646 } 5647 } 5648 5649 if (have_var) { 5650 unsigned int n = 0; 5651 5652 seq_puts(m, ":"); 5653 5654 for_each_hist_val_field(i, hist_data) { 5655 field = hist_data->fields[i]; 5656 5657 if (field->flags & HIST_FIELD_FL_VAR) { 5658 if (n++) 5659 seq_puts(m, ","); 5660 hist_field_print(m, field); 5661 } 5662 } 5663 } 5664 5665 seq_puts(m, ":sort="); 5666 5667 for (i = 0; i < hist_data->n_sort_keys; i++) { 5668 struct tracing_map_sort_key *sort_key; 5669 unsigned int idx, first_key_idx; 5670 5671 /* skip VAR vals */ 5672 first_key_idx = hist_data->n_vals - hist_data->n_vars; 5673 5674 sort_key = &hist_data->sort_keys[i]; 5675 idx = sort_key->field_idx; 5676 5677 if (WARN_ON(idx >= HIST_FIELDS_MAX)) 5678 return -EINVAL; 5679 5680 if (i > 0) 5681 seq_puts(m, ","); 5682 5683 if (idx == HITCOUNT_IDX) 5684 seq_puts(m, "hitcount"); 5685 else { 5686 if (idx >= first_key_idx) 5687 idx += hist_data->n_vars; 5688 hist_field_print(m, hist_data->fields[idx]); 5689 } 5690 5691 if (sort_key->descending) 5692 seq_puts(m, ".descending"); 5693 } 5694 seq_printf(m, ":size=%u", (1 << hist_data->map->map_bits)); 5695 if (hist_data->enable_timestamps) 5696 seq_printf(m, ":clock=%s", hist_data->attrs->clock); 5697 5698 print_actions_spec(m, hist_data); 5699 5700 if (data->filter_str) 5701 seq_printf(m, " if %s", data->filter_str); 5702 5703 if (data->paused) 5704 seq_puts(m, " [paused]"); 5705 else 5706 seq_puts(m, " [active]"); 5707 5708 seq_putc(m, '\n'); 5709 5710 return 0; 5711 } 5712 5713 static int event_hist_trigger_init(struct event_trigger_ops *ops, 5714 struct event_trigger_data *data) 5715 { 5716 struct hist_trigger_data *hist_data = data->private_data; 5717 5718 if (!data->ref && hist_data->attrs->name) 5719 save_named_trigger(hist_data->attrs->name, data); 5720 5721 data->ref++; 5722 5723 return 0; 5724 } 5725 5726 static void unregister_field_var_hists(struct hist_trigger_data *hist_data) 5727 { 5728 struct trace_event_file *file; 5729 unsigned int i; 5730 char *cmd; 5731 int ret; 5732 5733 for (i = 0; i < hist_data->n_field_var_hists; i++) { 5734 file = hist_data->field_var_hists[i]->hist_data->event_file; 5735 cmd = hist_data->field_var_hists[i]->cmd; 5736 ret = event_hist_trigger_parse(&trigger_hist_cmd, file, 5737 "!hist", "hist", cmd); 5738 WARN_ON_ONCE(ret < 0); 5739 } 5740 } 5741 5742 static void event_hist_trigger_free(struct event_trigger_ops *ops, 5743 struct event_trigger_data *data) 5744 { 5745 struct hist_trigger_data *hist_data = data->private_data; 5746 5747 if (WARN_ON_ONCE(data->ref <= 0)) 5748 return; 5749 5750 data->ref--; 5751 if (!data->ref) { 5752 if (data->name) 5753 del_named_trigger(data); 5754 5755 trigger_data_free(data); 5756 5757 remove_hist_vars(hist_data); 5758 5759 unregister_field_var_hists(hist_data); 5760 5761 destroy_hist_data(hist_data); 5762 } 5763 } 5764 5765 static struct event_trigger_ops event_hist_trigger_ops = { 5766 .trigger = event_hist_trigger, 5767 .print = event_hist_trigger_print, 5768 .init = event_hist_trigger_init, 5769 .free = event_hist_trigger_free, 5770 }; 5771 5772 static int event_hist_trigger_named_init(struct event_trigger_ops *ops, 5773 struct event_trigger_data *data) 5774 { 5775 data->ref++; 5776 5777 save_named_trigger(data->named_data->name, data); 5778 5779 event_hist_trigger_init(ops, data->named_data); 5780 5781 return 0; 5782 } 5783 5784 static void event_hist_trigger_named_free(struct event_trigger_ops *ops, 5785 struct event_trigger_data *data) 5786 { 5787 if (WARN_ON_ONCE(data->ref <= 0)) 5788 return; 5789 5790 event_hist_trigger_free(ops, data->named_data); 5791 5792 data->ref--; 5793 if (!data->ref) { 5794 del_named_trigger(data); 5795 trigger_data_free(data); 5796 } 5797 } 5798 5799 static struct event_trigger_ops event_hist_trigger_named_ops = { 5800 .trigger = event_hist_trigger, 5801 .print = event_hist_trigger_print, 5802 .init = event_hist_trigger_named_init, 5803 .free = event_hist_trigger_named_free, 5804 }; 5805 5806 static struct event_trigger_ops *event_hist_get_trigger_ops(char *cmd, 5807 char *param) 5808 { 5809 return &event_hist_trigger_ops; 5810 } 5811 5812 static void hist_clear(struct event_trigger_data *data) 5813 { 5814 struct hist_trigger_data *hist_data = data->private_data; 5815 5816 if (data->name) 5817 pause_named_trigger(data); 5818 5819 tracepoint_synchronize_unregister(); 5820 5821 tracing_map_clear(hist_data->map); 5822 5823 if (data->name) 5824 unpause_named_trigger(data); 5825 } 5826 5827 static bool compatible_field(struct ftrace_event_field *field, 5828 struct ftrace_event_field *test_field) 5829 { 5830 if (field == test_field) 5831 return true; 5832 if (field == NULL || test_field == NULL) 5833 return false; 5834 if (strcmp(field->name, test_field->name) != 0) 5835 return false; 5836 if (strcmp(field->type, test_field->type) != 0) 5837 return false; 5838 if (field->size != test_field->size) 5839 return false; 5840 if (field->is_signed != test_field->is_signed) 5841 return false; 5842 5843 return true; 5844 } 5845 5846 static bool hist_trigger_match(struct event_trigger_data *data, 5847 struct event_trigger_data *data_test, 5848 struct event_trigger_data *named_data, 5849 bool ignore_filter) 5850 { 5851 struct tracing_map_sort_key *sort_key, *sort_key_test; 5852 struct hist_trigger_data *hist_data, *hist_data_test; 5853 struct hist_field *key_field, *key_field_test; 5854 unsigned int i; 5855 5856 if (named_data && (named_data != data_test) && 5857 (named_data != data_test->named_data)) 5858 return false; 5859 5860 if (!named_data && is_named_trigger(data_test)) 5861 return false; 5862 5863 hist_data = data->private_data; 5864 hist_data_test = data_test->private_data; 5865 5866 if (hist_data->n_vals != hist_data_test->n_vals || 5867 hist_data->n_fields != hist_data_test->n_fields || 5868 hist_data->n_sort_keys != hist_data_test->n_sort_keys) 5869 return false; 5870 5871 if (!ignore_filter) { 5872 if ((data->filter_str && !data_test->filter_str) || 5873 (!data->filter_str && data_test->filter_str)) 5874 return false; 5875 } 5876 5877 for_each_hist_field(i, hist_data) { 5878 key_field = hist_data->fields[i]; 5879 key_field_test = hist_data_test->fields[i]; 5880 5881 if (key_field->flags != key_field_test->flags) 5882 return false; 5883 if (!compatible_field(key_field->field, key_field_test->field)) 5884 return false; 5885 if (key_field->offset != key_field_test->offset) 5886 return false; 5887 if (key_field->size != key_field_test->size) 5888 return false; 5889 if (key_field->is_signed != key_field_test->is_signed) 5890 return false; 5891 if (!!key_field->var.name != !!key_field_test->var.name) 5892 return false; 5893 if (key_field->var.name && 5894 strcmp(key_field->var.name, key_field_test->var.name) != 0) 5895 return false; 5896 } 5897 5898 for (i = 0; i < hist_data->n_sort_keys; i++) { 5899 sort_key = &hist_data->sort_keys[i]; 5900 sort_key_test = &hist_data_test->sort_keys[i]; 5901 5902 if (sort_key->field_idx != sort_key_test->field_idx || 5903 sort_key->descending != sort_key_test->descending) 5904 return false; 5905 } 5906 5907 if (!ignore_filter && data->filter_str && 5908 (strcmp(data->filter_str, data_test->filter_str) != 0)) 5909 return false; 5910 5911 if (!actions_match(hist_data, hist_data_test)) 5912 return false; 5913 5914 return true; 5915 } 5916 5917 static int hist_register_trigger(char *glob, 5918 struct event_trigger_data *data, 5919 struct trace_event_file *file) 5920 { 5921 struct hist_trigger_data *hist_data = data->private_data; 5922 struct event_trigger_data *test, *named_data = NULL; 5923 struct trace_array *tr = file->tr; 5924 int ret = 0; 5925 5926 if (hist_data->attrs->name) { 5927 named_data = find_named_trigger(hist_data->attrs->name); 5928 if (named_data) { 5929 if (!hist_trigger_match(data, named_data, named_data, 5930 true)) { 5931 hist_err(tr, HIST_ERR_NAMED_MISMATCH, errpos(hist_data->attrs->name)); 5932 ret = -EINVAL; 5933 goto out; 5934 } 5935 } 5936 } 5937 5938 if (hist_data->attrs->name && !named_data) 5939 goto new; 5940 5941 lockdep_assert_held(&event_mutex); 5942 5943 list_for_each_entry(test, &file->triggers, list) { 5944 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 5945 if (!hist_trigger_match(data, test, named_data, false)) 5946 continue; 5947 if (hist_data->attrs->pause) 5948 test->paused = true; 5949 else if (hist_data->attrs->cont) 5950 test->paused = false; 5951 else if (hist_data->attrs->clear) 5952 hist_clear(test); 5953 else { 5954 hist_err(tr, HIST_ERR_TRIGGER_EEXIST, 0); 5955 ret = -EEXIST; 5956 } 5957 goto out; 5958 } 5959 } 5960 new: 5961 if (hist_data->attrs->cont || hist_data->attrs->clear) { 5962 hist_err(tr, HIST_ERR_TRIGGER_ENOENT_CLEAR, 0); 5963 ret = -ENOENT; 5964 goto out; 5965 } 5966 5967 if (hist_data->attrs->pause) 5968 data->paused = true; 5969 5970 if (named_data) { 5971 data->private_data = named_data->private_data; 5972 set_named_trigger_data(data, named_data); 5973 data->ops = &event_hist_trigger_named_ops; 5974 } 5975 5976 if (data->ops->init) { 5977 ret = data->ops->init(data->ops, data); 5978 if (ret < 0) 5979 goto out; 5980 } 5981 5982 if (hist_data->enable_timestamps) { 5983 char *clock = hist_data->attrs->clock; 5984 5985 ret = tracing_set_clock(file->tr, hist_data->attrs->clock); 5986 if (ret) { 5987 hist_err(tr, HIST_ERR_SET_CLOCK_FAIL, errpos(clock)); 5988 goto out; 5989 } 5990 5991 tracing_set_filter_buffering(file->tr, true); 5992 } 5993 5994 if (named_data) 5995 destroy_hist_data(hist_data); 5996 5997 ret++; 5998 out: 5999 return ret; 6000 } 6001 6002 static int hist_trigger_enable(struct event_trigger_data *data, 6003 struct trace_event_file *file) 6004 { 6005 int ret = 0; 6006 6007 list_add_tail_rcu(&data->list, &file->triggers); 6008 6009 update_cond_flag(file); 6010 6011 if (trace_event_trigger_enable_disable(file, 1) < 0) { 6012 list_del_rcu(&data->list); 6013 update_cond_flag(file); 6014 ret--; 6015 } 6016 6017 return ret; 6018 } 6019 6020 static bool have_hist_trigger_match(struct event_trigger_data *data, 6021 struct trace_event_file *file) 6022 { 6023 struct hist_trigger_data *hist_data = data->private_data; 6024 struct event_trigger_data *test, *named_data = NULL; 6025 bool match = false; 6026 6027 lockdep_assert_held(&event_mutex); 6028 6029 if (hist_data->attrs->name) 6030 named_data = find_named_trigger(hist_data->attrs->name); 6031 6032 list_for_each_entry(test, &file->triggers, list) { 6033 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6034 if (hist_trigger_match(data, test, named_data, false)) { 6035 match = true; 6036 break; 6037 } 6038 } 6039 } 6040 6041 return match; 6042 } 6043 6044 static bool hist_trigger_check_refs(struct event_trigger_data *data, 6045 struct trace_event_file *file) 6046 { 6047 struct hist_trigger_data *hist_data = data->private_data; 6048 struct event_trigger_data *test, *named_data = NULL; 6049 6050 lockdep_assert_held(&event_mutex); 6051 6052 if (hist_data->attrs->name) 6053 named_data = find_named_trigger(hist_data->attrs->name); 6054 6055 list_for_each_entry(test, &file->triggers, list) { 6056 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6057 if (!hist_trigger_match(data, test, named_data, false)) 6058 continue; 6059 hist_data = test->private_data; 6060 if (check_var_refs(hist_data)) 6061 return true; 6062 break; 6063 } 6064 } 6065 6066 return false; 6067 } 6068 6069 static void hist_unregister_trigger(char *glob, 6070 struct event_trigger_data *data, 6071 struct trace_event_file *file) 6072 { 6073 struct hist_trigger_data *hist_data = data->private_data; 6074 struct event_trigger_data *test, *named_data = NULL; 6075 bool unregistered = false; 6076 6077 lockdep_assert_held(&event_mutex); 6078 6079 if (hist_data->attrs->name) 6080 named_data = find_named_trigger(hist_data->attrs->name); 6081 6082 list_for_each_entry(test, &file->triggers, list) { 6083 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6084 if (!hist_trigger_match(data, test, named_data, false)) 6085 continue; 6086 unregistered = true; 6087 list_del_rcu(&test->list); 6088 trace_event_trigger_enable_disable(file, 0); 6089 update_cond_flag(file); 6090 break; 6091 } 6092 } 6093 6094 if (unregistered && test->ops->free) 6095 test->ops->free(test->ops, test); 6096 6097 if (hist_data->enable_timestamps) { 6098 if (!hist_data->remove || unregistered) 6099 tracing_set_filter_buffering(file->tr, false); 6100 } 6101 } 6102 6103 static bool hist_file_check_refs(struct trace_event_file *file) 6104 { 6105 struct hist_trigger_data *hist_data; 6106 struct event_trigger_data *test; 6107 6108 lockdep_assert_held(&event_mutex); 6109 6110 list_for_each_entry(test, &file->triggers, list) { 6111 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6112 hist_data = test->private_data; 6113 if (check_var_refs(hist_data)) 6114 return true; 6115 } 6116 } 6117 6118 return false; 6119 } 6120 6121 static void hist_unreg_all(struct trace_event_file *file) 6122 { 6123 struct event_trigger_data *test, *n; 6124 struct hist_trigger_data *hist_data; 6125 struct synth_event *se; 6126 const char *se_name; 6127 6128 lockdep_assert_held(&event_mutex); 6129 6130 if (hist_file_check_refs(file)) 6131 return; 6132 6133 list_for_each_entry_safe(test, n, &file->triggers, list) { 6134 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6135 hist_data = test->private_data; 6136 list_del_rcu(&test->list); 6137 trace_event_trigger_enable_disable(file, 0); 6138 6139 se_name = trace_event_name(file->event_call); 6140 se = find_synth_event(se_name); 6141 if (se) 6142 se->ref--; 6143 6144 update_cond_flag(file); 6145 if (hist_data->enable_timestamps) 6146 tracing_set_filter_buffering(file->tr, false); 6147 if (test->ops->free) 6148 test->ops->free(test->ops, test); 6149 } 6150 } 6151 } 6152 6153 static int event_hist_trigger_parse(struct event_command *cmd_ops, 6154 struct trace_event_file *file, 6155 char *glob, char *cmd, char *param) 6156 { 6157 unsigned int hist_trigger_bits = TRACING_MAP_BITS_DEFAULT; 6158 struct event_trigger_data *trigger_data; 6159 struct hist_trigger_attrs *attrs; 6160 struct event_trigger_ops *trigger_ops; 6161 struct hist_trigger_data *hist_data; 6162 struct synth_event *se; 6163 const char *se_name; 6164 bool remove = false; 6165 char *trigger, *p, *start; 6166 int ret = 0; 6167 6168 lockdep_assert_held(&event_mutex); 6169 6170 WARN_ON(!glob); 6171 6172 if (strlen(glob)) { 6173 hist_err_clear(); 6174 last_cmd_set(file, param); 6175 } 6176 6177 if (!param) 6178 return -EINVAL; 6179 6180 if (glob[0] == '!') 6181 remove = true; 6182 6183 /* 6184 * separate the trigger from the filter (k:v [if filter]) 6185 * allowing for whitespace in the trigger 6186 */ 6187 p = trigger = param; 6188 do { 6189 p = strstr(p, "if"); 6190 if (!p) 6191 break; 6192 if (p == param) 6193 return -EINVAL; 6194 if (*(p - 1) != ' ' && *(p - 1) != '\t') { 6195 p++; 6196 continue; 6197 } 6198 if (p >= param + strlen(param) - (sizeof("if") - 1) - 1) 6199 return -EINVAL; 6200 if (*(p + sizeof("if") - 1) != ' ' && *(p + sizeof("if") - 1) != '\t') { 6201 p++; 6202 continue; 6203 } 6204 break; 6205 } while (1); 6206 6207 if (!p) 6208 param = NULL; 6209 else { 6210 *(p - 1) = '\0'; 6211 param = strstrip(p); 6212 trigger = strstrip(trigger); 6213 } 6214 6215 /* 6216 * To simplify arithmetic expression parsing, replace occurrences of 6217 * '.sym-offset' modifier with '.symXoffset' 6218 */ 6219 start = strstr(trigger, ".sym-offset"); 6220 while (start) { 6221 *(start + 4) = 'X'; 6222 start = strstr(start + 11, ".sym-offset"); 6223 } 6224 6225 attrs = parse_hist_trigger_attrs(file->tr, trigger); 6226 if (IS_ERR(attrs)) 6227 return PTR_ERR(attrs); 6228 6229 if (attrs->map_bits) 6230 hist_trigger_bits = attrs->map_bits; 6231 6232 hist_data = create_hist_data(hist_trigger_bits, attrs, file, remove); 6233 if (IS_ERR(hist_data)) { 6234 destroy_hist_trigger_attrs(attrs); 6235 return PTR_ERR(hist_data); 6236 } 6237 6238 trigger_ops = cmd_ops->get_trigger_ops(cmd, trigger); 6239 6240 trigger_data = kzalloc(sizeof(*trigger_data), GFP_KERNEL); 6241 if (!trigger_data) { 6242 ret = -ENOMEM; 6243 goto out_free; 6244 } 6245 6246 trigger_data->count = -1; 6247 trigger_data->ops = trigger_ops; 6248 trigger_data->cmd_ops = cmd_ops; 6249 6250 INIT_LIST_HEAD(&trigger_data->list); 6251 RCU_INIT_POINTER(trigger_data->filter, NULL); 6252 6253 trigger_data->private_data = hist_data; 6254 6255 /* if param is non-empty, it's supposed to be a filter */ 6256 if (param && cmd_ops->set_filter) { 6257 ret = cmd_ops->set_filter(param, trigger_data, file); 6258 if (ret < 0) 6259 goto out_free; 6260 } 6261 6262 if (remove) { 6263 if (!have_hist_trigger_match(trigger_data, file)) 6264 goto out_free; 6265 6266 if (hist_trigger_check_refs(trigger_data, file)) { 6267 ret = -EBUSY; 6268 goto out_free; 6269 } 6270 6271 cmd_ops->unreg(glob+1, trigger_data, file); 6272 se_name = trace_event_name(file->event_call); 6273 se = find_synth_event(se_name); 6274 if (se) 6275 se->ref--; 6276 ret = 0; 6277 goto out_free; 6278 } 6279 6280 ret = cmd_ops->reg(glob, trigger_data, file); 6281 /* 6282 * The above returns on success the # of triggers registered, 6283 * but if it didn't register any it returns zero. Consider no 6284 * triggers registered a failure too. 6285 */ 6286 if (!ret) { 6287 if (!(attrs->pause || attrs->cont || attrs->clear)) 6288 ret = -ENOENT; 6289 goto out_free; 6290 } else if (ret < 0) 6291 goto out_free; 6292 6293 if (get_named_trigger_data(trigger_data)) 6294 goto enable; 6295 6296 if (has_hist_vars(hist_data)) 6297 save_hist_vars(hist_data); 6298 6299 ret = create_actions(hist_data); 6300 if (ret) 6301 goto out_unreg; 6302 6303 ret = tracing_map_init(hist_data->map); 6304 if (ret) 6305 goto out_unreg; 6306 enable: 6307 ret = hist_trigger_enable(trigger_data, file); 6308 if (ret) 6309 goto out_unreg; 6310 6311 se_name = trace_event_name(file->event_call); 6312 se = find_synth_event(se_name); 6313 if (se) 6314 se->ref++; 6315 /* Just return zero, not the number of registered triggers */ 6316 ret = 0; 6317 out: 6318 if (ret == 0) 6319 hist_err_clear(); 6320 6321 return ret; 6322 out_unreg: 6323 cmd_ops->unreg(glob+1, trigger_data, file); 6324 out_free: 6325 if (cmd_ops->set_filter) 6326 cmd_ops->set_filter(NULL, trigger_data, NULL); 6327 6328 remove_hist_vars(hist_data); 6329 6330 kfree(trigger_data); 6331 6332 destroy_hist_data(hist_data); 6333 goto out; 6334 } 6335 6336 static struct event_command trigger_hist_cmd = { 6337 .name = "hist", 6338 .trigger_type = ETT_EVENT_HIST, 6339 .flags = EVENT_CMD_FL_NEEDS_REC, 6340 .parse = event_hist_trigger_parse, 6341 .reg = hist_register_trigger, 6342 .unreg = hist_unregister_trigger, 6343 .unreg_all = hist_unreg_all, 6344 .get_trigger_ops = event_hist_get_trigger_ops, 6345 .set_filter = set_trigger_filter, 6346 }; 6347 6348 __init int register_trigger_hist_cmd(void) 6349 { 6350 int ret; 6351 6352 ret = register_event_command(&trigger_hist_cmd); 6353 WARN_ON(ret < 0); 6354 6355 return ret; 6356 } 6357 6358 static void 6359 hist_enable_trigger(struct event_trigger_data *data, 6360 struct trace_buffer *buffer, void *rec, 6361 struct ring_buffer_event *event) 6362 { 6363 struct enable_trigger_data *enable_data = data->private_data; 6364 struct event_trigger_data *test; 6365 6366 list_for_each_entry_rcu(test, &enable_data->file->triggers, list, 6367 lockdep_is_held(&event_mutex)) { 6368 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6369 if (enable_data->enable) 6370 test->paused = false; 6371 else 6372 test->paused = true; 6373 } 6374 } 6375 } 6376 6377 static void 6378 hist_enable_count_trigger(struct event_trigger_data *data, 6379 struct trace_buffer *buffer, void *rec, 6380 struct ring_buffer_event *event) 6381 { 6382 if (!data->count) 6383 return; 6384 6385 if (data->count != -1) 6386 (data->count)--; 6387 6388 hist_enable_trigger(data, buffer, rec, event); 6389 } 6390 6391 static struct event_trigger_ops hist_enable_trigger_ops = { 6392 .trigger = hist_enable_trigger, 6393 .print = event_enable_trigger_print, 6394 .init = event_trigger_init, 6395 .free = event_enable_trigger_free, 6396 }; 6397 6398 static struct event_trigger_ops hist_enable_count_trigger_ops = { 6399 .trigger = hist_enable_count_trigger, 6400 .print = event_enable_trigger_print, 6401 .init = event_trigger_init, 6402 .free = event_enable_trigger_free, 6403 }; 6404 6405 static struct event_trigger_ops hist_disable_trigger_ops = { 6406 .trigger = hist_enable_trigger, 6407 .print = event_enable_trigger_print, 6408 .init = event_trigger_init, 6409 .free = event_enable_trigger_free, 6410 }; 6411 6412 static struct event_trigger_ops hist_disable_count_trigger_ops = { 6413 .trigger = hist_enable_count_trigger, 6414 .print = event_enable_trigger_print, 6415 .init = event_trigger_init, 6416 .free = event_enable_trigger_free, 6417 }; 6418 6419 static struct event_trigger_ops * 6420 hist_enable_get_trigger_ops(char *cmd, char *param) 6421 { 6422 struct event_trigger_ops *ops; 6423 bool enable; 6424 6425 enable = (strcmp(cmd, ENABLE_HIST_STR) == 0); 6426 6427 if (enable) 6428 ops = param ? &hist_enable_count_trigger_ops : 6429 &hist_enable_trigger_ops; 6430 else 6431 ops = param ? &hist_disable_count_trigger_ops : 6432 &hist_disable_trigger_ops; 6433 6434 return ops; 6435 } 6436 6437 static void hist_enable_unreg_all(struct trace_event_file *file) 6438 { 6439 struct event_trigger_data *test, *n; 6440 6441 list_for_each_entry_safe(test, n, &file->triggers, list) { 6442 if (test->cmd_ops->trigger_type == ETT_HIST_ENABLE) { 6443 list_del_rcu(&test->list); 6444 update_cond_flag(file); 6445 trace_event_trigger_enable_disable(file, 0); 6446 if (test->ops->free) 6447 test->ops->free(test->ops, test); 6448 } 6449 } 6450 } 6451 6452 static struct event_command trigger_hist_enable_cmd = { 6453 .name = ENABLE_HIST_STR, 6454 .trigger_type = ETT_HIST_ENABLE, 6455 .parse = event_enable_trigger_parse, 6456 .reg = event_enable_register_trigger, 6457 .unreg = event_enable_unregister_trigger, 6458 .unreg_all = hist_enable_unreg_all, 6459 .get_trigger_ops = hist_enable_get_trigger_ops, 6460 .set_filter = set_trigger_filter, 6461 }; 6462 6463 static struct event_command trigger_hist_disable_cmd = { 6464 .name = DISABLE_HIST_STR, 6465 .trigger_type = ETT_HIST_ENABLE, 6466 .parse = event_enable_trigger_parse, 6467 .reg = event_enable_register_trigger, 6468 .unreg = event_enable_unregister_trigger, 6469 .unreg_all = hist_enable_unreg_all, 6470 .get_trigger_ops = hist_enable_get_trigger_ops, 6471 .set_filter = set_trigger_filter, 6472 }; 6473 6474 static __init void unregister_trigger_hist_enable_disable_cmds(void) 6475 { 6476 unregister_event_command(&trigger_hist_enable_cmd); 6477 unregister_event_command(&trigger_hist_disable_cmd); 6478 } 6479 6480 __init int register_trigger_hist_enable_disable_cmds(void) 6481 { 6482 int ret; 6483 6484 ret = register_event_command(&trigger_hist_enable_cmd); 6485 if (WARN_ON(ret < 0)) 6486 return ret; 6487 ret = register_event_command(&trigger_hist_disable_cmd); 6488 if (WARN_ON(ret < 0)) 6489 unregister_trigger_hist_enable_disable_cmds(); 6490 6491 return ret; 6492 } 6493