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 #define HIST_PREFIX "hist:" 731 732 static char *last_cmd; 733 static char last_cmd_loc[MAX_FILTER_STR_VAL]; 734 735 static int errpos(char *str) 736 { 737 if (!str || !last_cmd) 738 return 0; 739 740 return err_pos(last_cmd, str); 741 } 742 743 static void last_cmd_set(struct trace_event_file *file, char *str) 744 { 745 const char *system = NULL, *name = NULL; 746 struct trace_event_call *call; 747 int len; 748 749 if (!str) 750 return; 751 752 /* sizeof() contains the nul byte */ 753 len = sizeof(HIST_PREFIX) + strlen(str); 754 kfree(last_cmd); 755 last_cmd = kzalloc(len, GFP_KERNEL); 756 if (!last_cmd) 757 return; 758 759 strcpy(last_cmd, HIST_PREFIX); 760 /* Again, sizeof() contains the nul byte */ 761 len -= sizeof(HIST_PREFIX); 762 strncat(last_cmd, str, len); 763 764 if (file) { 765 call = file->event_call; 766 system = call->class->system; 767 if (system) { 768 name = trace_event_name(call); 769 if (!name) 770 system = NULL; 771 } 772 } 773 774 if (system) 775 snprintf(last_cmd_loc, MAX_FILTER_STR_VAL, HIST_PREFIX "%s:%s", system, name); 776 } 777 778 static void hist_err(struct trace_array *tr, u8 err_type, u16 err_pos) 779 { 780 if (!last_cmd) 781 return; 782 783 tracing_log_err(tr, last_cmd_loc, last_cmd, err_text, 784 err_type, err_pos); 785 } 786 787 static void hist_err_clear(void) 788 { 789 if (last_cmd) 790 last_cmd[0] = '\0'; 791 last_cmd_loc[0] = '\0'; 792 } 793 794 typedef void (*synth_probe_func_t) (void *__data, u64 *var_ref_vals, 795 unsigned int *var_ref_idx); 796 797 static inline void trace_synth(struct synth_event *event, u64 *var_ref_vals, 798 unsigned int *var_ref_idx) 799 { 800 struct tracepoint *tp = event->tp; 801 802 if (unlikely(atomic_read(&tp->key.enabled) > 0)) { 803 struct tracepoint_func *probe_func_ptr; 804 synth_probe_func_t probe_func; 805 void *__data; 806 807 if (!(cpu_online(raw_smp_processor_id()))) 808 return; 809 810 probe_func_ptr = rcu_dereference_sched((tp)->funcs); 811 if (probe_func_ptr) { 812 do { 813 probe_func = probe_func_ptr->func; 814 __data = probe_func_ptr->data; 815 probe_func(__data, var_ref_vals, var_ref_idx); 816 } while ((++probe_func_ptr)->func); 817 } 818 } 819 } 820 821 static void action_trace(struct hist_trigger_data *hist_data, 822 struct tracing_map_elt *elt, 823 struct trace_buffer *buffer, void *rec, 824 struct ring_buffer_event *rbe, void *key, 825 struct action_data *data, u64 *var_ref_vals) 826 { 827 struct synth_event *event = data->synth_event; 828 829 trace_synth(event, var_ref_vals, data->var_ref_idx); 830 } 831 832 struct hist_var_data { 833 struct list_head list; 834 struct hist_trigger_data *hist_data; 835 }; 836 837 static u64 hist_field_timestamp(struct hist_field *hist_field, 838 struct tracing_map_elt *elt, 839 struct trace_buffer *buffer, 840 struct ring_buffer_event *rbe, 841 void *event) 842 { 843 struct hist_trigger_data *hist_data = hist_field->hist_data; 844 struct trace_array *tr = hist_data->event_file->tr; 845 846 u64 ts = ring_buffer_event_time_stamp(buffer, rbe); 847 848 if (hist_data->attrs->ts_in_usecs && trace_clock_in_ns(tr)) 849 ts = ns2usecs(ts); 850 851 return ts; 852 } 853 854 static u64 hist_field_cpu(struct hist_field *hist_field, 855 struct tracing_map_elt *elt, 856 struct trace_buffer *buffer, 857 struct ring_buffer_event *rbe, 858 void *event) 859 { 860 int cpu = smp_processor_id(); 861 862 return cpu; 863 } 864 865 /** 866 * check_field_for_var_ref - Check if a VAR_REF field references a variable 867 * @hist_field: The VAR_REF field to check 868 * @var_data: The hist trigger that owns the variable 869 * @var_idx: The trigger variable identifier 870 * 871 * Check the given VAR_REF field to see whether or not it references 872 * the given variable associated with the given trigger. 873 * 874 * Return: The VAR_REF field if it does reference the variable, NULL if not 875 */ 876 static struct hist_field * 877 check_field_for_var_ref(struct hist_field *hist_field, 878 struct hist_trigger_data *var_data, 879 unsigned int var_idx) 880 { 881 WARN_ON(!(hist_field && hist_field->flags & HIST_FIELD_FL_VAR_REF)); 882 883 if (hist_field && hist_field->var.idx == var_idx && 884 hist_field->var.hist_data == var_data) 885 return hist_field; 886 887 return NULL; 888 } 889 890 /** 891 * find_var_ref - Check if a trigger has a reference to a trigger variable 892 * @hist_data: The hist trigger that might have a reference to the variable 893 * @var_data: The hist trigger that owns the variable 894 * @var_idx: The trigger variable identifier 895 * 896 * Check the list of var_refs[] on the first hist trigger to see 897 * whether any of them are references to the variable on the second 898 * trigger. 899 * 900 * Return: The VAR_REF field referencing the variable if so, NULL if not 901 */ 902 static struct hist_field *find_var_ref(struct hist_trigger_data *hist_data, 903 struct hist_trigger_data *var_data, 904 unsigned int var_idx) 905 { 906 struct hist_field *hist_field; 907 unsigned int i; 908 909 for (i = 0; i < hist_data->n_var_refs; i++) { 910 hist_field = hist_data->var_refs[i]; 911 if (check_field_for_var_ref(hist_field, var_data, var_idx)) 912 return hist_field; 913 } 914 915 return NULL; 916 } 917 918 /** 919 * find_any_var_ref - Check if there is a reference to a given trigger variable 920 * @hist_data: The hist trigger 921 * @var_idx: The trigger variable identifier 922 * 923 * Check to see whether the given variable is currently referenced by 924 * any other trigger. 925 * 926 * The trigger the variable is defined on is explicitly excluded - the 927 * assumption being that a self-reference doesn't prevent a trigger 928 * from being removed. 929 * 930 * Return: The VAR_REF field referencing the variable if so, NULL if not 931 */ 932 static struct hist_field *find_any_var_ref(struct hist_trigger_data *hist_data, 933 unsigned int var_idx) 934 { 935 struct trace_array *tr = hist_data->event_file->tr; 936 struct hist_field *found = NULL; 937 struct hist_var_data *var_data; 938 939 list_for_each_entry(var_data, &tr->hist_vars, list) { 940 if (var_data->hist_data == hist_data) 941 continue; 942 found = find_var_ref(var_data->hist_data, hist_data, var_idx); 943 if (found) 944 break; 945 } 946 947 return found; 948 } 949 950 /** 951 * check_var_refs - Check if there is a reference to any of trigger's variables 952 * @hist_data: The hist trigger 953 * 954 * A trigger can define one or more variables. If any one of them is 955 * currently referenced by any other trigger, this function will 956 * determine that. 957 958 * Typically used to determine whether or not a trigger can be removed 959 * - if there are any references to a trigger's variables, it cannot. 960 * 961 * Return: True if there is a reference to any of trigger's variables 962 */ 963 static bool check_var_refs(struct hist_trigger_data *hist_data) 964 { 965 struct hist_field *field; 966 bool found = false; 967 int i; 968 969 for_each_hist_field(i, hist_data) { 970 field = hist_data->fields[i]; 971 if (field && field->flags & HIST_FIELD_FL_VAR) { 972 if (find_any_var_ref(hist_data, field->var.idx)) { 973 found = true; 974 break; 975 } 976 } 977 } 978 979 return found; 980 } 981 982 static struct hist_var_data *find_hist_vars(struct hist_trigger_data *hist_data) 983 { 984 struct trace_array *tr = hist_data->event_file->tr; 985 struct hist_var_data *var_data, *found = NULL; 986 987 list_for_each_entry(var_data, &tr->hist_vars, list) { 988 if (var_data->hist_data == hist_data) { 989 found = var_data; 990 break; 991 } 992 } 993 994 return found; 995 } 996 997 static bool field_has_hist_vars(struct hist_field *hist_field, 998 unsigned int level) 999 { 1000 int i; 1001 1002 if (level > 3) 1003 return false; 1004 1005 if (!hist_field) 1006 return false; 1007 1008 if (hist_field->flags & HIST_FIELD_FL_VAR || 1009 hist_field->flags & HIST_FIELD_FL_VAR_REF) 1010 return true; 1011 1012 for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++) { 1013 struct hist_field *operand; 1014 1015 operand = hist_field->operands[i]; 1016 if (field_has_hist_vars(operand, level + 1)) 1017 return true; 1018 } 1019 1020 return false; 1021 } 1022 1023 static bool has_hist_vars(struct hist_trigger_data *hist_data) 1024 { 1025 struct hist_field *hist_field; 1026 int i; 1027 1028 for_each_hist_field(i, hist_data) { 1029 hist_field = hist_data->fields[i]; 1030 if (field_has_hist_vars(hist_field, 0)) 1031 return true; 1032 } 1033 1034 return false; 1035 } 1036 1037 static int save_hist_vars(struct hist_trigger_data *hist_data) 1038 { 1039 struct trace_array *tr = hist_data->event_file->tr; 1040 struct hist_var_data *var_data; 1041 1042 var_data = find_hist_vars(hist_data); 1043 if (var_data) 1044 return 0; 1045 1046 if (tracing_check_open_get_tr(tr)) 1047 return -ENODEV; 1048 1049 var_data = kzalloc(sizeof(*var_data), GFP_KERNEL); 1050 if (!var_data) { 1051 trace_array_put(tr); 1052 return -ENOMEM; 1053 } 1054 1055 var_data->hist_data = hist_data; 1056 list_add(&var_data->list, &tr->hist_vars); 1057 1058 return 0; 1059 } 1060 1061 static void remove_hist_vars(struct hist_trigger_data *hist_data) 1062 { 1063 struct trace_array *tr = hist_data->event_file->tr; 1064 struct hist_var_data *var_data; 1065 1066 var_data = find_hist_vars(hist_data); 1067 if (!var_data) 1068 return; 1069 1070 if (WARN_ON(check_var_refs(hist_data))) 1071 return; 1072 1073 list_del(&var_data->list); 1074 1075 kfree(var_data); 1076 1077 trace_array_put(tr); 1078 } 1079 1080 static struct hist_field *find_var_field(struct hist_trigger_data *hist_data, 1081 const char *var_name) 1082 { 1083 struct hist_field *hist_field, *found = NULL; 1084 int i; 1085 1086 for_each_hist_field(i, hist_data) { 1087 hist_field = hist_data->fields[i]; 1088 if (hist_field && hist_field->flags & HIST_FIELD_FL_VAR && 1089 strcmp(hist_field->var.name, var_name) == 0) { 1090 found = hist_field; 1091 break; 1092 } 1093 } 1094 1095 return found; 1096 } 1097 1098 static struct hist_field *find_var(struct hist_trigger_data *hist_data, 1099 struct trace_event_file *file, 1100 const char *var_name) 1101 { 1102 struct hist_trigger_data *test_data; 1103 struct event_trigger_data *test; 1104 struct hist_field *hist_field; 1105 1106 lockdep_assert_held(&event_mutex); 1107 1108 hist_field = find_var_field(hist_data, var_name); 1109 if (hist_field) 1110 return hist_field; 1111 1112 list_for_each_entry(test, &file->triggers, list) { 1113 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 1114 test_data = test->private_data; 1115 hist_field = find_var_field(test_data, var_name); 1116 if (hist_field) 1117 return hist_field; 1118 } 1119 } 1120 1121 return NULL; 1122 } 1123 1124 static struct trace_event_file *find_var_file(struct trace_array *tr, 1125 char *system, 1126 char *event_name, 1127 char *var_name) 1128 { 1129 struct hist_trigger_data *var_hist_data; 1130 struct hist_var_data *var_data; 1131 struct trace_event_file *file, *found = NULL; 1132 1133 if (system) 1134 return find_event_file(tr, system, event_name); 1135 1136 list_for_each_entry(var_data, &tr->hist_vars, list) { 1137 var_hist_data = var_data->hist_data; 1138 file = var_hist_data->event_file; 1139 if (file == found) 1140 continue; 1141 1142 if (find_var_field(var_hist_data, var_name)) { 1143 if (found) { 1144 hist_err(tr, HIST_ERR_VAR_NOT_UNIQUE, errpos(var_name)); 1145 return NULL; 1146 } 1147 1148 found = file; 1149 } 1150 } 1151 1152 return found; 1153 } 1154 1155 static struct hist_field *find_file_var(struct trace_event_file *file, 1156 const char *var_name) 1157 { 1158 struct hist_trigger_data *test_data; 1159 struct event_trigger_data *test; 1160 struct hist_field *hist_field; 1161 1162 lockdep_assert_held(&event_mutex); 1163 1164 list_for_each_entry(test, &file->triggers, list) { 1165 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 1166 test_data = test->private_data; 1167 hist_field = find_var_field(test_data, var_name); 1168 if (hist_field) 1169 return hist_field; 1170 } 1171 } 1172 1173 return NULL; 1174 } 1175 1176 static struct hist_field * 1177 find_match_var(struct hist_trigger_data *hist_data, char *var_name) 1178 { 1179 struct trace_array *tr = hist_data->event_file->tr; 1180 struct hist_field *hist_field, *found = NULL; 1181 struct trace_event_file *file; 1182 unsigned int i; 1183 1184 for (i = 0; i < hist_data->n_actions; i++) { 1185 struct action_data *data = hist_data->actions[i]; 1186 1187 if (data->handler == HANDLER_ONMATCH) { 1188 char *system = data->match_data.event_system; 1189 char *event_name = data->match_data.event; 1190 1191 file = find_var_file(tr, system, event_name, var_name); 1192 if (!file) 1193 continue; 1194 hist_field = find_file_var(file, var_name); 1195 if (hist_field) { 1196 if (found) { 1197 hist_err(tr, HIST_ERR_VAR_NOT_UNIQUE, 1198 errpos(var_name)); 1199 return ERR_PTR(-EINVAL); 1200 } 1201 1202 found = hist_field; 1203 } 1204 } 1205 } 1206 return found; 1207 } 1208 1209 static struct hist_field *find_event_var(struct hist_trigger_data *hist_data, 1210 char *system, 1211 char *event_name, 1212 char *var_name) 1213 { 1214 struct trace_array *tr = hist_data->event_file->tr; 1215 struct hist_field *hist_field = NULL; 1216 struct trace_event_file *file; 1217 1218 if (!system || !event_name) { 1219 hist_field = find_match_var(hist_data, var_name); 1220 if (IS_ERR(hist_field)) 1221 return NULL; 1222 if (hist_field) 1223 return hist_field; 1224 } 1225 1226 file = find_var_file(tr, system, event_name, var_name); 1227 if (!file) 1228 return NULL; 1229 1230 hist_field = find_file_var(file, var_name); 1231 1232 return hist_field; 1233 } 1234 1235 static u64 hist_field_var_ref(struct hist_field *hist_field, 1236 struct tracing_map_elt *elt, 1237 struct trace_buffer *buffer, 1238 struct ring_buffer_event *rbe, 1239 void *event) 1240 { 1241 struct hist_elt_data *elt_data; 1242 u64 var_val = 0; 1243 1244 if (WARN_ON_ONCE(!elt)) 1245 return var_val; 1246 1247 elt_data = elt->private_data; 1248 var_val = elt_data->var_ref_vals[hist_field->var_ref_idx]; 1249 1250 return var_val; 1251 } 1252 1253 static bool resolve_var_refs(struct hist_trigger_data *hist_data, void *key, 1254 u64 *var_ref_vals, bool self) 1255 { 1256 struct hist_trigger_data *var_data; 1257 struct tracing_map_elt *var_elt; 1258 struct hist_field *hist_field; 1259 unsigned int i, var_idx; 1260 bool resolved = true; 1261 u64 var_val = 0; 1262 1263 for (i = 0; i < hist_data->n_var_refs; i++) { 1264 hist_field = hist_data->var_refs[i]; 1265 var_idx = hist_field->var.idx; 1266 var_data = hist_field->var.hist_data; 1267 1268 if (var_data == NULL) { 1269 resolved = false; 1270 break; 1271 } 1272 1273 if ((self && var_data != hist_data) || 1274 (!self && var_data == hist_data)) 1275 continue; 1276 1277 var_elt = tracing_map_lookup(var_data->map, key); 1278 if (!var_elt) { 1279 resolved = false; 1280 break; 1281 } 1282 1283 if (!tracing_map_var_set(var_elt, var_idx)) { 1284 resolved = false; 1285 break; 1286 } 1287 1288 if (self || !hist_field->read_once) 1289 var_val = tracing_map_read_var(var_elt, var_idx); 1290 else 1291 var_val = tracing_map_read_var_once(var_elt, var_idx); 1292 1293 var_ref_vals[i] = var_val; 1294 } 1295 1296 return resolved; 1297 } 1298 1299 static const char *hist_field_name(struct hist_field *field, 1300 unsigned int level) 1301 { 1302 const char *field_name = ""; 1303 1304 if (level > 1) 1305 return field_name; 1306 1307 if (field->field) 1308 field_name = field->field->name; 1309 else if (field->flags & HIST_FIELD_FL_LOG2 || 1310 field->flags & HIST_FIELD_FL_ALIAS || 1311 field->flags & HIST_FIELD_FL_BUCKET) 1312 field_name = hist_field_name(field->operands[0], ++level); 1313 else if (field->flags & HIST_FIELD_FL_CPU) 1314 field_name = "common_cpu"; 1315 else if (field->flags & HIST_FIELD_FL_EXPR || 1316 field->flags & HIST_FIELD_FL_VAR_REF) { 1317 if (field->system) { 1318 static char full_name[MAX_FILTER_STR_VAL]; 1319 1320 strcat(full_name, field->system); 1321 strcat(full_name, "."); 1322 strcat(full_name, field->event_name); 1323 strcat(full_name, "."); 1324 strcat(full_name, field->name); 1325 field_name = full_name; 1326 } else 1327 field_name = field->name; 1328 } else if (field->flags & HIST_FIELD_FL_TIMESTAMP) 1329 field_name = "common_timestamp"; 1330 1331 if (field_name == NULL) 1332 field_name = ""; 1333 1334 return field_name; 1335 } 1336 1337 static hist_field_fn_t select_value_fn(int field_size, int field_is_signed) 1338 { 1339 hist_field_fn_t fn = NULL; 1340 1341 switch (field_size) { 1342 case 8: 1343 if (field_is_signed) 1344 fn = hist_field_s64; 1345 else 1346 fn = hist_field_u64; 1347 break; 1348 case 4: 1349 if (field_is_signed) 1350 fn = hist_field_s32; 1351 else 1352 fn = hist_field_u32; 1353 break; 1354 case 2: 1355 if (field_is_signed) 1356 fn = hist_field_s16; 1357 else 1358 fn = hist_field_u16; 1359 break; 1360 case 1: 1361 if (field_is_signed) 1362 fn = hist_field_s8; 1363 else 1364 fn = hist_field_u8; 1365 break; 1366 } 1367 1368 return fn; 1369 } 1370 1371 static int parse_map_size(char *str) 1372 { 1373 unsigned long size, map_bits; 1374 int ret; 1375 1376 ret = kstrtoul(str, 0, &size); 1377 if (ret) 1378 goto out; 1379 1380 map_bits = ilog2(roundup_pow_of_two(size)); 1381 if (map_bits < TRACING_MAP_BITS_MIN || 1382 map_bits > TRACING_MAP_BITS_MAX) 1383 ret = -EINVAL; 1384 else 1385 ret = map_bits; 1386 out: 1387 return ret; 1388 } 1389 1390 static void destroy_hist_trigger_attrs(struct hist_trigger_attrs *attrs) 1391 { 1392 unsigned int i; 1393 1394 if (!attrs) 1395 return; 1396 1397 for (i = 0; i < attrs->n_assignments; i++) 1398 kfree(attrs->assignment_str[i]); 1399 1400 for (i = 0; i < attrs->n_actions; i++) 1401 kfree(attrs->action_str[i]); 1402 1403 kfree(attrs->name); 1404 kfree(attrs->sort_key_str); 1405 kfree(attrs->keys_str); 1406 kfree(attrs->vals_str); 1407 kfree(attrs->clock); 1408 kfree(attrs); 1409 } 1410 1411 static int parse_action(char *str, struct hist_trigger_attrs *attrs) 1412 { 1413 int ret = -EINVAL; 1414 1415 if (attrs->n_actions >= HIST_ACTIONS_MAX) 1416 return ret; 1417 1418 if ((str_has_prefix(str, "onmatch(")) || 1419 (str_has_prefix(str, "onmax(")) || 1420 (str_has_prefix(str, "onchange("))) { 1421 attrs->action_str[attrs->n_actions] = kstrdup(str, GFP_KERNEL); 1422 if (!attrs->action_str[attrs->n_actions]) { 1423 ret = -ENOMEM; 1424 return ret; 1425 } 1426 attrs->n_actions++; 1427 ret = 0; 1428 } 1429 return ret; 1430 } 1431 1432 static int parse_assignment(struct trace_array *tr, 1433 char *str, struct hist_trigger_attrs *attrs) 1434 { 1435 int len, ret = 0; 1436 1437 if ((len = str_has_prefix(str, "key=")) || 1438 (len = str_has_prefix(str, "keys="))) { 1439 attrs->keys_str = kstrdup(str + len, GFP_KERNEL); 1440 if (!attrs->keys_str) { 1441 ret = -ENOMEM; 1442 goto out; 1443 } 1444 } else if ((len = str_has_prefix(str, "val=")) || 1445 (len = str_has_prefix(str, "vals=")) || 1446 (len = str_has_prefix(str, "values="))) { 1447 attrs->vals_str = kstrdup(str + len, GFP_KERNEL); 1448 if (!attrs->vals_str) { 1449 ret = -ENOMEM; 1450 goto out; 1451 } 1452 } else if ((len = str_has_prefix(str, "sort="))) { 1453 attrs->sort_key_str = kstrdup(str + len, GFP_KERNEL); 1454 if (!attrs->sort_key_str) { 1455 ret = -ENOMEM; 1456 goto out; 1457 } 1458 } else if (str_has_prefix(str, "name=")) { 1459 attrs->name = kstrdup(str, GFP_KERNEL); 1460 if (!attrs->name) { 1461 ret = -ENOMEM; 1462 goto out; 1463 } 1464 } else if ((len = str_has_prefix(str, "clock="))) { 1465 str += len; 1466 1467 str = strstrip(str); 1468 attrs->clock = kstrdup(str, GFP_KERNEL); 1469 if (!attrs->clock) { 1470 ret = -ENOMEM; 1471 goto out; 1472 } 1473 } else if ((len = str_has_prefix(str, "size="))) { 1474 int map_bits = parse_map_size(str + len); 1475 1476 if (map_bits < 0) { 1477 ret = map_bits; 1478 goto out; 1479 } 1480 attrs->map_bits = map_bits; 1481 } else { 1482 char *assignment; 1483 1484 if (attrs->n_assignments == TRACING_MAP_VARS_MAX) { 1485 hist_err(tr, HIST_ERR_TOO_MANY_VARS, errpos(str)); 1486 ret = -EINVAL; 1487 goto out; 1488 } 1489 1490 assignment = kstrdup(str, GFP_KERNEL); 1491 if (!assignment) { 1492 ret = -ENOMEM; 1493 goto out; 1494 } 1495 1496 attrs->assignment_str[attrs->n_assignments++] = assignment; 1497 } 1498 out: 1499 return ret; 1500 } 1501 1502 static struct hist_trigger_attrs * 1503 parse_hist_trigger_attrs(struct trace_array *tr, char *trigger_str) 1504 { 1505 struct hist_trigger_attrs *attrs; 1506 int ret = 0; 1507 1508 attrs = kzalloc(sizeof(*attrs), GFP_KERNEL); 1509 if (!attrs) 1510 return ERR_PTR(-ENOMEM); 1511 1512 while (trigger_str) { 1513 char *str = strsep(&trigger_str, ":"); 1514 char *rhs; 1515 1516 rhs = strchr(str, '='); 1517 if (rhs) { 1518 if (!strlen(++rhs)) { 1519 ret = -EINVAL; 1520 hist_err(tr, HIST_ERR_EMPTY_ASSIGNMENT, errpos(str)); 1521 goto free; 1522 } 1523 ret = parse_assignment(tr, str, attrs); 1524 if (ret) 1525 goto free; 1526 } else if (strcmp(str, "pause") == 0) 1527 attrs->pause = true; 1528 else if ((strcmp(str, "cont") == 0) || 1529 (strcmp(str, "continue") == 0)) 1530 attrs->cont = true; 1531 else if (strcmp(str, "clear") == 0) 1532 attrs->clear = true; 1533 else { 1534 ret = parse_action(str, attrs); 1535 if (ret) 1536 goto free; 1537 } 1538 } 1539 1540 if (!attrs->keys_str) { 1541 ret = -EINVAL; 1542 goto free; 1543 } 1544 1545 if (!attrs->clock) { 1546 attrs->clock = kstrdup("global", GFP_KERNEL); 1547 if (!attrs->clock) { 1548 ret = -ENOMEM; 1549 goto free; 1550 } 1551 } 1552 1553 return attrs; 1554 free: 1555 destroy_hist_trigger_attrs(attrs); 1556 1557 return ERR_PTR(ret); 1558 } 1559 1560 static inline void save_comm(char *comm, struct task_struct *task) 1561 { 1562 if (!task->pid) { 1563 strcpy(comm, "<idle>"); 1564 return; 1565 } 1566 1567 if (WARN_ON_ONCE(task->pid < 0)) { 1568 strcpy(comm, "<XXX>"); 1569 return; 1570 } 1571 1572 strncpy(comm, task->comm, TASK_COMM_LEN); 1573 } 1574 1575 static void hist_elt_data_free(struct hist_elt_data *elt_data) 1576 { 1577 unsigned int i; 1578 1579 for (i = 0; i < elt_data->n_field_var_str; i++) 1580 kfree(elt_data->field_var_str[i]); 1581 1582 kfree(elt_data->field_var_str); 1583 1584 kfree(elt_data->comm); 1585 kfree(elt_data); 1586 } 1587 1588 static void hist_trigger_elt_data_free(struct tracing_map_elt *elt) 1589 { 1590 struct hist_elt_data *elt_data = elt->private_data; 1591 1592 hist_elt_data_free(elt_data); 1593 } 1594 1595 static int hist_trigger_elt_data_alloc(struct tracing_map_elt *elt) 1596 { 1597 struct hist_trigger_data *hist_data = elt->map->private_data; 1598 unsigned int size = TASK_COMM_LEN; 1599 struct hist_elt_data *elt_data; 1600 struct hist_field *hist_field; 1601 unsigned int i, n_str; 1602 1603 elt_data = kzalloc(sizeof(*elt_data), GFP_KERNEL); 1604 if (!elt_data) 1605 return -ENOMEM; 1606 1607 for_each_hist_field(i, hist_data) { 1608 hist_field = hist_data->fields[i]; 1609 1610 if (hist_field->flags & HIST_FIELD_FL_EXECNAME) { 1611 elt_data->comm = kzalloc(size, GFP_KERNEL); 1612 if (!elt_data->comm) { 1613 kfree(elt_data); 1614 return -ENOMEM; 1615 } 1616 break; 1617 } 1618 } 1619 1620 n_str = hist_data->n_field_var_str + hist_data->n_save_var_str + 1621 hist_data->n_var_str; 1622 if (n_str > SYNTH_FIELDS_MAX) { 1623 hist_elt_data_free(elt_data); 1624 return -EINVAL; 1625 } 1626 1627 BUILD_BUG_ON(STR_VAR_LEN_MAX & (sizeof(u64) - 1)); 1628 1629 size = STR_VAR_LEN_MAX; 1630 1631 elt_data->field_var_str = kcalloc(n_str, sizeof(char *), GFP_KERNEL); 1632 if (!elt_data->field_var_str) { 1633 hist_elt_data_free(elt_data); 1634 return -EINVAL; 1635 } 1636 elt_data->n_field_var_str = n_str; 1637 1638 for (i = 0; i < n_str; i++) { 1639 elt_data->field_var_str[i] = kzalloc(size, GFP_KERNEL); 1640 if (!elt_data->field_var_str[i]) { 1641 hist_elt_data_free(elt_data); 1642 return -ENOMEM; 1643 } 1644 } 1645 1646 elt->private_data = elt_data; 1647 1648 return 0; 1649 } 1650 1651 static void hist_trigger_elt_data_init(struct tracing_map_elt *elt) 1652 { 1653 struct hist_elt_data *elt_data = elt->private_data; 1654 1655 if (elt_data->comm) 1656 save_comm(elt_data->comm, current); 1657 } 1658 1659 static const struct tracing_map_ops hist_trigger_elt_data_ops = { 1660 .elt_alloc = hist_trigger_elt_data_alloc, 1661 .elt_free = hist_trigger_elt_data_free, 1662 .elt_init = hist_trigger_elt_data_init, 1663 }; 1664 1665 static const char *get_hist_field_flags(struct hist_field *hist_field) 1666 { 1667 const char *flags_str = NULL; 1668 1669 if (hist_field->flags & HIST_FIELD_FL_HEX) 1670 flags_str = "hex"; 1671 else if (hist_field->flags & HIST_FIELD_FL_SYM) 1672 flags_str = "sym"; 1673 else if (hist_field->flags & HIST_FIELD_FL_SYM_OFFSET) 1674 flags_str = "sym-offset"; 1675 else if (hist_field->flags & HIST_FIELD_FL_EXECNAME) 1676 flags_str = "execname"; 1677 else if (hist_field->flags & HIST_FIELD_FL_SYSCALL) 1678 flags_str = "syscall"; 1679 else if (hist_field->flags & HIST_FIELD_FL_LOG2) 1680 flags_str = "log2"; 1681 else if (hist_field->flags & HIST_FIELD_FL_BUCKET) 1682 flags_str = "buckets"; 1683 else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP_USECS) 1684 flags_str = "usecs"; 1685 1686 return flags_str; 1687 } 1688 1689 static void expr_field_str(struct hist_field *field, char *expr) 1690 { 1691 if (field->flags & HIST_FIELD_FL_VAR_REF) 1692 strcat(expr, "$"); 1693 else if (field->flags & HIST_FIELD_FL_CONST) { 1694 char str[HIST_CONST_DIGITS_MAX]; 1695 1696 snprintf(str, HIST_CONST_DIGITS_MAX, "%llu", field->constant); 1697 strcat(expr, str); 1698 } 1699 1700 strcat(expr, hist_field_name(field, 0)); 1701 1702 if (field->flags && !(field->flags & HIST_FIELD_FL_VAR_REF)) { 1703 const char *flags_str = get_hist_field_flags(field); 1704 1705 if (flags_str) { 1706 strcat(expr, "."); 1707 strcat(expr, flags_str); 1708 } 1709 } 1710 } 1711 1712 static char *expr_str(struct hist_field *field, unsigned int level) 1713 { 1714 char *expr; 1715 1716 if (level > 1) 1717 return NULL; 1718 1719 expr = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL); 1720 if (!expr) 1721 return NULL; 1722 1723 if (!field->operands[0]) { 1724 expr_field_str(field, expr); 1725 return expr; 1726 } 1727 1728 if (field->operator == FIELD_OP_UNARY_MINUS) { 1729 char *subexpr; 1730 1731 strcat(expr, "-("); 1732 subexpr = expr_str(field->operands[0], ++level); 1733 if (!subexpr) { 1734 kfree(expr); 1735 return NULL; 1736 } 1737 strcat(expr, subexpr); 1738 strcat(expr, ")"); 1739 1740 kfree(subexpr); 1741 1742 return expr; 1743 } 1744 1745 expr_field_str(field->operands[0], expr); 1746 1747 switch (field->operator) { 1748 case FIELD_OP_MINUS: 1749 strcat(expr, "-"); 1750 break; 1751 case FIELD_OP_PLUS: 1752 strcat(expr, "+"); 1753 break; 1754 case FIELD_OP_DIV: 1755 strcat(expr, "/"); 1756 break; 1757 case FIELD_OP_MULT: 1758 strcat(expr, "*"); 1759 break; 1760 default: 1761 kfree(expr); 1762 return NULL; 1763 } 1764 1765 expr_field_str(field->operands[1], expr); 1766 1767 return expr; 1768 } 1769 1770 /* 1771 * If field_op != FIELD_OP_NONE, *sep points to the root operator 1772 * of the expression tree to be evaluated. 1773 */ 1774 static int contains_operator(char *str, char **sep) 1775 { 1776 enum field_op_id field_op = FIELD_OP_NONE; 1777 char *minus_op, *plus_op, *div_op, *mult_op; 1778 1779 1780 /* 1781 * Report the last occurrence of the operators first, so that the 1782 * expression is evaluated left to right. This is important since 1783 * subtraction and division are not associative. 1784 * 1785 * e.g 1786 * 64/8/4/2 is 1, i.e 64/8/4/2 = ((64/8)/4)/2 1787 * 14-7-5-2 is 0, i.e 14-7-5-2 = ((14-7)-5)-2 1788 */ 1789 1790 /* 1791 * First, find lower precedence addition and subtraction 1792 * since the expression will be evaluated recursively. 1793 */ 1794 minus_op = strrchr(str, '-'); 1795 if (minus_op) { 1796 /* 1797 * Unary minus is not supported in sub-expressions. If 1798 * present, it is always the next root operator. 1799 */ 1800 if (minus_op == str) { 1801 field_op = FIELD_OP_UNARY_MINUS; 1802 goto out; 1803 } 1804 1805 field_op = FIELD_OP_MINUS; 1806 } 1807 1808 plus_op = strrchr(str, '+'); 1809 if (plus_op || minus_op) { 1810 /* 1811 * For operators of the same precedence use to rightmost as the 1812 * root, so that the expression is evaluated left to right. 1813 */ 1814 if (plus_op > minus_op) 1815 field_op = FIELD_OP_PLUS; 1816 goto out; 1817 } 1818 1819 /* 1820 * Multiplication and division have higher precedence than addition and 1821 * subtraction. 1822 */ 1823 div_op = strrchr(str, '/'); 1824 if (div_op) 1825 field_op = FIELD_OP_DIV; 1826 1827 mult_op = strrchr(str, '*'); 1828 /* 1829 * For operators of the same precedence use to rightmost as the 1830 * root, so that the expression is evaluated left to right. 1831 */ 1832 if (mult_op > div_op) 1833 field_op = FIELD_OP_MULT; 1834 1835 out: 1836 if (sep) { 1837 switch (field_op) { 1838 case FIELD_OP_UNARY_MINUS: 1839 case FIELD_OP_MINUS: 1840 *sep = minus_op; 1841 break; 1842 case FIELD_OP_PLUS: 1843 *sep = plus_op; 1844 break; 1845 case FIELD_OP_DIV: 1846 *sep = div_op; 1847 break; 1848 case FIELD_OP_MULT: 1849 *sep = mult_op; 1850 break; 1851 case FIELD_OP_NONE: 1852 default: 1853 *sep = NULL; 1854 break; 1855 } 1856 } 1857 1858 return field_op; 1859 } 1860 1861 static void get_hist_field(struct hist_field *hist_field) 1862 { 1863 hist_field->ref++; 1864 } 1865 1866 static void __destroy_hist_field(struct hist_field *hist_field) 1867 { 1868 if (--hist_field->ref > 1) 1869 return; 1870 1871 kfree(hist_field->var.name); 1872 kfree(hist_field->name); 1873 1874 /* Can likely be a const */ 1875 kfree_const(hist_field->type); 1876 1877 kfree(hist_field->system); 1878 kfree(hist_field->event_name); 1879 1880 kfree(hist_field); 1881 } 1882 1883 static void destroy_hist_field(struct hist_field *hist_field, 1884 unsigned int level) 1885 { 1886 unsigned int i; 1887 1888 if (level > 3) 1889 return; 1890 1891 if (!hist_field) 1892 return; 1893 1894 if (hist_field->flags & HIST_FIELD_FL_VAR_REF) 1895 return; /* var refs will be destroyed separately */ 1896 1897 for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++) 1898 destroy_hist_field(hist_field->operands[i], level + 1); 1899 1900 __destroy_hist_field(hist_field); 1901 } 1902 1903 static struct hist_field *create_hist_field(struct hist_trigger_data *hist_data, 1904 struct ftrace_event_field *field, 1905 unsigned long flags, 1906 char *var_name) 1907 { 1908 struct hist_field *hist_field; 1909 1910 if (field && is_function_field(field)) 1911 return NULL; 1912 1913 hist_field = kzalloc(sizeof(struct hist_field), GFP_KERNEL); 1914 if (!hist_field) 1915 return NULL; 1916 1917 hist_field->ref = 1; 1918 1919 hist_field->hist_data = hist_data; 1920 1921 if (flags & HIST_FIELD_FL_EXPR || flags & HIST_FIELD_FL_ALIAS) 1922 goto out; /* caller will populate */ 1923 1924 if (flags & HIST_FIELD_FL_VAR_REF) { 1925 hist_field->fn = hist_field_var_ref; 1926 goto out; 1927 } 1928 1929 if (flags & HIST_FIELD_FL_HITCOUNT) { 1930 hist_field->fn = hist_field_counter; 1931 hist_field->size = sizeof(u64); 1932 hist_field->type = "u64"; 1933 goto out; 1934 } 1935 1936 if (flags & HIST_FIELD_FL_CONST) { 1937 hist_field->fn = hist_field_const; 1938 hist_field->size = sizeof(u64); 1939 hist_field->type = kstrdup("u64", GFP_KERNEL); 1940 if (!hist_field->type) 1941 goto free; 1942 goto out; 1943 } 1944 1945 if (flags & HIST_FIELD_FL_STACKTRACE) { 1946 hist_field->fn = hist_field_none; 1947 goto out; 1948 } 1949 1950 if (flags & (HIST_FIELD_FL_LOG2 | HIST_FIELD_FL_BUCKET)) { 1951 unsigned long fl = flags & ~(HIST_FIELD_FL_LOG2 | HIST_FIELD_FL_BUCKET); 1952 hist_field->fn = flags & HIST_FIELD_FL_LOG2 ? hist_field_log2 : 1953 hist_field_bucket; 1954 hist_field->operands[0] = create_hist_field(hist_data, field, fl, NULL); 1955 hist_field->size = hist_field->operands[0]->size; 1956 hist_field->type = kstrdup_const(hist_field->operands[0]->type, GFP_KERNEL); 1957 if (!hist_field->type) 1958 goto free; 1959 goto out; 1960 } 1961 1962 if (flags & HIST_FIELD_FL_TIMESTAMP) { 1963 hist_field->fn = hist_field_timestamp; 1964 hist_field->size = sizeof(u64); 1965 hist_field->type = "u64"; 1966 goto out; 1967 } 1968 1969 if (flags & HIST_FIELD_FL_CPU) { 1970 hist_field->fn = hist_field_cpu; 1971 hist_field->size = sizeof(int); 1972 hist_field->type = "unsigned int"; 1973 goto out; 1974 } 1975 1976 if (WARN_ON_ONCE(!field)) 1977 goto out; 1978 1979 /* Pointers to strings are just pointers and dangerous to dereference */ 1980 if (is_string_field(field) && 1981 (field->filter_type != FILTER_PTR_STRING)) { 1982 flags |= HIST_FIELD_FL_STRING; 1983 1984 hist_field->size = MAX_FILTER_STR_VAL; 1985 hist_field->type = kstrdup_const(field->type, GFP_KERNEL); 1986 if (!hist_field->type) 1987 goto free; 1988 1989 if (field->filter_type == FILTER_STATIC_STRING) { 1990 hist_field->fn = hist_field_string; 1991 hist_field->size = field->size; 1992 } else if (field->filter_type == FILTER_DYN_STRING) { 1993 hist_field->fn = hist_field_dynstring; 1994 } else if (field->filter_type == FILTER_RDYN_STRING) 1995 hist_field->fn = hist_field_reldynstring; 1996 else 1997 hist_field->fn = hist_field_pstring; 1998 } else { 1999 hist_field->size = field->size; 2000 hist_field->is_signed = field->is_signed; 2001 hist_field->type = kstrdup_const(field->type, GFP_KERNEL); 2002 if (!hist_field->type) 2003 goto free; 2004 2005 hist_field->fn = select_value_fn(field->size, 2006 field->is_signed); 2007 if (!hist_field->fn) { 2008 destroy_hist_field(hist_field, 0); 2009 return NULL; 2010 } 2011 } 2012 out: 2013 hist_field->field = field; 2014 hist_field->flags = flags; 2015 2016 if (var_name) { 2017 hist_field->var.name = kstrdup(var_name, GFP_KERNEL); 2018 if (!hist_field->var.name) 2019 goto free; 2020 } 2021 2022 return hist_field; 2023 free: 2024 destroy_hist_field(hist_field, 0); 2025 return NULL; 2026 } 2027 2028 static void destroy_hist_fields(struct hist_trigger_data *hist_data) 2029 { 2030 unsigned int i; 2031 2032 for (i = 0; i < HIST_FIELDS_MAX; i++) { 2033 if (hist_data->fields[i]) { 2034 destroy_hist_field(hist_data->fields[i], 0); 2035 hist_data->fields[i] = NULL; 2036 } 2037 } 2038 2039 for (i = 0; i < hist_data->n_var_refs; i++) { 2040 WARN_ON(!(hist_data->var_refs[i]->flags & HIST_FIELD_FL_VAR_REF)); 2041 __destroy_hist_field(hist_data->var_refs[i]); 2042 hist_data->var_refs[i] = NULL; 2043 } 2044 } 2045 2046 static int init_var_ref(struct hist_field *ref_field, 2047 struct hist_field *var_field, 2048 char *system, char *event_name) 2049 { 2050 int err = 0; 2051 2052 ref_field->var.idx = var_field->var.idx; 2053 ref_field->var.hist_data = var_field->hist_data; 2054 ref_field->size = var_field->size; 2055 ref_field->is_signed = var_field->is_signed; 2056 ref_field->flags |= var_field->flags & 2057 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS); 2058 2059 if (system) { 2060 ref_field->system = kstrdup(system, GFP_KERNEL); 2061 if (!ref_field->system) 2062 return -ENOMEM; 2063 } 2064 2065 if (event_name) { 2066 ref_field->event_name = kstrdup(event_name, GFP_KERNEL); 2067 if (!ref_field->event_name) { 2068 err = -ENOMEM; 2069 goto free; 2070 } 2071 } 2072 2073 if (var_field->var.name) { 2074 ref_field->name = kstrdup(var_field->var.name, GFP_KERNEL); 2075 if (!ref_field->name) { 2076 err = -ENOMEM; 2077 goto free; 2078 } 2079 } else if (var_field->name) { 2080 ref_field->name = kstrdup(var_field->name, GFP_KERNEL); 2081 if (!ref_field->name) { 2082 err = -ENOMEM; 2083 goto free; 2084 } 2085 } 2086 2087 ref_field->type = kstrdup_const(var_field->type, GFP_KERNEL); 2088 if (!ref_field->type) { 2089 err = -ENOMEM; 2090 goto free; 2091 } 2092 out: 2093 return err; 2094 free: 2095 kfree(ref_field->system); 2096 kfree(ref_field->event_name); 2097 kfree(ref_field->name); 2098 2099 goto out; 2100 } 2101 2102 static int find_var_ref_idx(struct hist_trigger_data *hist_data, 2103 struct hist_field *var_field) 2104 { 2105 struct hist_field *ref_field; 2106 int i; 2107 2108 for (i = 0; i < hist_data->n_var_refs; i++) { 2109 ref_field = hist_data->var_refs[i]; 2110 if (ref_field->var.idx == var_field->var.idx && 2111 ref_field->var.hist_data == var_field->hist_data) 2112 return i; 2113 } 2114 2115 return -ENOENT; 2116 } 2117 2118 /** 2119 * create_var_ref - Create a variable reference and attach it to trigger 2120 * @hist_data: The trigger that will be referencing the variable 2121 * @var_field: The VAR field to create a reference to 2122 * @system: The optional system string 2123 * @event_name: The optional event_name string 2124 * 2125 * Given a variable hist_field, create a VAR_REF hist_field that 2126 * represents a reference to it. 2127 * 2128 * This function also adds the reference to the trigger that 2129 * now references the variable. 2130 * 2131 * Return: The VAR_REF field if successful, NULL if not 2132 */ 2133 static struct hist_field *create_var_ref(struct hist_trigger_data *hist_data, 2134 struct hist_field *var_field, 2135 char *system, char *event_name) 2136 { 2137 unsigned long flags = HIST_FIELD_FL_VAR_REF; 2138 struct hist_field *ref_field; 2139 int i; 2140 2141 /* Check if the variable already exists */ 2142 for (i = 0; i < hist_data->n_var_refs; i++) { 2143 ref_field = hist_data->var_refs[i]; 2144 if (ref_field->var.idx == var_field->var.idx && 2145 ref_field->var.hist_data == var_field->hist_data) { 2146 get_hist_field(ref_field); 2147 return ref_field; 2148 } 2149 } 2150 2151 ref_field = create_hist_field(var_field->hist_data, NULL, flags, NULL); 2152 if (ref_field) { 2153 if (init_var_ref(ref_field, var_field, system, event_name)) { 2154 destroy_hist_field(ref_field, 0); 2155 return NULL; 2156 } 2157 2158 hist_data->var_refs[hist_data->n_var_refs] = ref_field; 2159 ref_field->var_ref_idx = hist_data->n_var_refs++; 2160 } 2161 2162 return ref_field; 2163 } 2164 2165 static bool is_var_ref(char *var_name) 2166 { 2167 if (!var_name || strlen(var_name) < 2 || var_name[0] != '$') 2168 return false; 2169 2170 return true; 2171 } 2172 2173 static char *field_name_from_var(struct hist_trigger_data *hist_data, 2174 char *var_name) 2175 { 2176 char *name, *field; 2177 unsigned int i; 2178 2179 for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) { 2180 name = hist_data->attrs->var_defs.name[i]; 2181 2182 if (strcmp(var_name, name) == 0) { 2183 field = hist_data->attrs->var_defs.expr[i]; 2184 if (contains_operator(field, NULL) || is_var_ref(field)) 2185 continue; 2186 return field; 2187 } 2188 } 2189 2190 return NULL; 2191 } 2192 2193 static char *local_field_var_ref(struct hist_trigger_data *hist_data, 2194 char *system, char *event_name, 2195 char *var_name) 2196 { 2197 struct trace_event_call *call; 2198 2199 if (system && event_name) { 2200 call = hist_data->event_file->event_call; 2201 2202 if (strcmp(system, call->class->system) != 0) 2203 return NULL; 2204 2205 if (strcmp(event_name, trace_event_name(call)) != 0) 2206 return NULL; 2207 } 2208 2209 if (!!system != !!event_name) 2210 return NULL; 2211 2212 if (!is_var_ref(var_name)) 2213 return NULL; 2214 2215 var_name++; 2216 2217 return field_name_from_var(hist_data, var_name); 2218 } 2219 2220 static struct hist_field *parse_var_ref(struct hist_trigger_data *hist_data, 2221 char *system, char *event_name, 2222 char *var_name) 2223 { 2224 struct hist_field *var_field = NULL, *ref_field = NULL; 2225 struct trace_array *tr = hist_data->event_file->tr; 2226 2227 if (!is_var_ref(var_name)) 2228 return NULL; 2229 2230 var_name++; 2231 2232 var_field = find_event_var(hist_data, system, event_name, var_name); 2233 if (var_field) 2234 ref_field = create_var_ref(hist_data, var_field, 2235 system, event_name); 2236 2237 if (!ref_field) 2238 hist_err(tr, HIST_ERR_VAR_NOT_FOUND, errpos(var_name)); 2239 2240 return ref_field; 2241 } 2242 2243 static struct ftrace_event_field * 2244 parse_field(struct hist_trigger_data *hist_data, struct trace_event_file *file, 2245 char *field_str, unsigned long *flags, unsigned long *buckets) 2246 { 2247 struct ftrace_event_field *field = NULL; 2248 char *field_name, *modifier, *str; 2249 struct trace_array *tr = file->tr; 2250 2251 modifier = str = kstrdup(field_str, GFP_KERNEL); 2252 if (!modifier) 2253 return ERR_PTR(-ENOMEM); 2254 2255 field_name = strsep(&modifier, "."); 2256 if (modifier) { 2257 if (strcmp(modifier, "hex") == 0) 2258 *flags |= HIST_FIELD_FL_HEX; 2259 else if (strcmp(modifier, "sym") == 0) 2260 *flags |= HIST_FIELD_FL_SYM; 2261 /* 2262 * 'sym-offset' occurrences in the trigger string are modified 2263 * to 'symXoffset' to simplify arithmetic expression parsing. 2264 */ 2265 else if (strcmp(modifier, "symXoffset") == 0) 2266 *flags |= HIST_FIELD_FL_SYM_OFFSET; 2267 else if ((strcmp(modifier, "execname") == 0) && 2268 (strcmp(field_name, "common_pid") == 0)) 2269 *flags |= HIST_FIELD_FL_EXECNAME; 2270 else if (strcmp(modifier, "syscall") == 0) 2271 *flags |= HIST_FIELD_FL_SYSCALL; 2272 else if (strcmp(modifier, "log2") == 0) 2273 *flags |= HIST_FIELD_FL_LOG2; 2274 else if (strcmp(modifier, "usecs") == 0) 2275 *flags |= HIST_FIELD_FL_TIMESTAMP_USECS; 2276 else if (strncmp(modifier, "bucket", 6) == 0) { 2277 int ret; 2278 2279 modifier += 6; 2280 2281 if (*modifier == 's') 2282 modifier++; 2283 if (*modifier != '=') 2284 goto error; 2285 modifier++; 2286 ret = kstrtoul(modifier, 0, buckets); 2287 if (ret || !(*buckets)) 2288 goto error; 2289 *flags |= HIST_FIELD_FL_BUCKET; 2290 } else { 2291 error: 2292 hist_err(tr, HIST_ERR_BAD_FIELD_MODIFIER, errpos(modifier)); 2293 field = ERR_PTR(-EINVAL); 2294 goto out; 2295 } 2296 } 2297 2298 if (strcmp(field_name, "common_timestamp") == 0) { 2299 *flags |= HIST_FIELD_FL_TIMESTAMP; 2300 hist_data->enable_timestamps = true; 2301 if (*flags & HIST_FIELD_FL_TIMESTAMP_USECS) 2302 hist_data->attrs->ts_in_usecs = true; 2303 } else if (strcmp(field_name, "common_cpu") == 0) 2304 *flags |= HIST_FIELD_FL_CPU; 2305 else { 2306 field = trace_find_event_field(file->event_call, field_name); 2307 if (!field || !field->size) { 2308 /* 2309 * For backward compatibility, if field_name 2310 * was "cpu", then we treat this the same as 2311 * common_cpu. This also works for "CPU". 2312 */ 2313 if (field && field->filter_type == FILTER_CPU) { 2314 *flags |= HIST_FIELD_FL_CPU; 2315 } else { 2316 hist_err(tr, HIST_ERR_FIELD_NOT_FOUND, 2317 errpos(field_name)); 2318 field = ERR_PTR(-EINVAL); 2319 goto out; 2320 } 2321 } 2322 } 2323 out: 2324 kfree(str); 2325 2326 return field; 2327 } 2328 2329 static struct hist_field *create_alias(struct hist_trigger_data *hist_data, 2330 struct hist_field *var_ref, 2331 char *var_name) 2332 { 2333 struct hist_field *alias = NULL; 2334 unsigned long flags = HIST_FIELD_FL_ALIAS | HIST_FIELD_FL_VAR; 2335 2336 alias = create_hist_field(hist_data, NULL, flags, var_name); 2337 if (!alias) 2338 return NULL; 2339 2340 alias->fn = var_ref->fn; 2341 alias->operands[0] = var_ref; 2342 2343 if (init_var_ref(alias, var_ref, var_ref->system, var_ref->event_name)) { 2344 destroy_hist_field(alias, 0); 2345 return NULL; 2346 } 2347 2348 alias->var_ref_idx = var_ref->var_ref_idx; 2349 2350 return alias; 2351 } 2352 2353 static struct hist_field *parse_const(struct hist_trigger_data *hist_data, 2354 char *str, char *var_name, 2355 unsigned long *flags) 2356 { 2357 struct trace_array *tr = hist_data->event_file->tr; 2358 struct hist_field *field = NULL; 2359 u64 constant; 2360 2361 if (kstrtoull(str, 0, &constant)) { 2362 hist_err(tr, HIST_ERR_EXPECT_NUMBER, errpos(str)); 2363 return NULL; 2364 } 2365 2366 *flags |= HIST_FIELD_FL_CONST; 2367 field = create_hist_field(hist_data, NULL, *flags, var_name); 2368 if (!field) 2369 return NULL; 2370 2371 field->constant = constant; 2372 2373 return field; 2374 } 2375 2376 static struct hist_field *parse_atom(struct hist_trigger_data *hist_data, 2377 struct trace_event_file *file, char *str, 2378 unsigned long *flags, char *var_name) 2379 { 2380 char *s, *ref_system = NULL, *ref_event = NULL, *ref_var = str; 2381 struct ftrace_event_field *field = NULL; 2382 struct hist_field *hist_field = NULL; 2383 unsigned long buckets = 0; 2384 int ret = 0; 2385 2386 if (isdigit(str[0])) { 2387 hist_field = parse_const(hist_data, str, var_name, flags); 2388 if (!hist_field) { 2389 ret = -EINVAL; 2390 goto out; 2391 } 2392 return hist_field; 2393 } 2394 2395 s = strchr(str, '.'); 2396 if (s) { 2397 s = strchr(++s, '.'); 2398 if (s) { 2399 ref_system = strsep(&str, "."); 2400 if (!str) { 2401 ret = -EINVAL; 2402 goto out; 2403 } 2404 ref_event = strsep(&str, "."); 2405 if (!str) { 2406 ret = -EINVAL; 2407 goto out; 2408 } 2409 ref_var = str; 2410 } 2411 } 2412 2413 s = local_field_var_ref(hist_data, ref_system, ref_event, ref_var); 2414 if (!s) { 2415 hist_field = parse_var_ref(hist_data, ref_system, 2416 ref_event, ref_var); 2417 if (hist_field) { 2418 if (var_name) { 2419 hist_field = create_alias(hist_data, hist_field, var_name); 2420 if (!hist_field) { 2421 ret = -ENOMEM; 2422 goto out; 2423 } 2424 } 2425 return hist_field; 2426 } 2427 } else 2428 str = s; 2429 2430 field = parse_field(hist_data, file, str, flags, &buckets); 2431 if (IS_ERR(field)) { 2432 ret = PTR_ERR(field); 2433 goto out; 2434 } 2435 2436 hist_field = create_hist_field(hist_data, field, *flags, var_name); 2437 if (!hist_field) { 2438 ret = -ENOMEM; 2439 goto out; 2440 } 2441 hist_field->buckets = buckets; 2442 2443 return hist_field; 2444 out: 2445 return ERR_PTR(ret); 2446 } 2447 2448 static struct hist_field *parse_expr(struct hist_trigger_data *hist_data, 2449 struct trace_event_file *file, 2450 char *str, unsigned long flags, 2451 char *var_name, unsigned int *n_subexprs); 2452 2453 static struct hist_field *parse_unary(struct hist_trigger_data *hist_data, 2454 struct trace_event_file *file, 2455 char *str, unsigned long flags, 2456 char *var_name, unsigned int *n_subexprs) 2457 { 2458 struct hist_field *operand1, *expr = NULL; 2459 unsigned long operand_flags; 2460 int ret = 0; 2461 char *s; 2462 2463 /* Unary minus operator, increment n_subexprs */ 2464 ++*n_subexprs; 2465 2466 /* we support only -(xxx) i.e. explicit parens required */ 2467 2468 if (*n_subexprs > 3) { 2469 hist_err(file->tr, HIST_ERR_TOO_MANY_SUBEXPR, errpos(str)); 2470 ret = -EINVAL; 2471 goto free; 2472 } 2473 2474 str++; /* skip leading '-' */ 2475 2476 s = strchr(str, '('); 2477 if (s) 2478 str++; 2479 else { 2480 ret = -EINVAL; 2481 goto free; 2482 } 2483 2484 s = strrchr(str, ')'); 2485 if (s) { 2486 /* unary minus not supported in sub-expressions */ 2487 if (*(s+1) != '\0') { 2488 hist_err(file->tr, HIST_ERR_UNARY_MINUS_SUBEXPR, 2489 errpos(str)); 2490 ret = -EINVAL; 2491 goto free; 2492 } 2493 *s = '\0'; 2494 } 2495 else { 2496 ret = -EINVAL; /* no closing ')' */ 2497 goto free; 2498 } 2499 2500 flags |= HIST_FIELD_FL_EXPR; 2501 expr = create_hist_field(hist_data, NULL, flags, var_name); 2502 if (!expr) { 2503 ret = -ENOMEM; 2504 goto free; 2505 } 2506 2507 operand_flags = 0; 2508 operand1 = parse_expr(hist_data, file, str, operand_flags, NULL, n_subexprs); 2509 if (IS_ERR(operand1)) { 2510 ret = PTR_ERR(operand1); 2511 goto free; 2512 } 2513 if (operand1->flags & HIST_FIELD_FL_STRING) { 2514 /* String type can not be the operand of unary operator. */ 2515 hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(str)); 2516 destroy_hist_field(operand1, 0); 2517 ret = -EINVAL; 2518 goto free; 2519 } 2520 2521 expr->flags |= operand1->flags & 2522 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS); 2523 expr->fn = hist_field_unary_minus; 2524 expr->operands[0] = operand1; 2525 expr->size = operand1->size; 2526 expr->is_signed = operand1->is_signed; 2527 expr->operator = FIELD_OP_UNARY_MINUS; 2528 expr->name = expr_str(expr, 0); 2529 expr->type = kstrdup_const(operand1->type, GFP_KERNEL); 2530 if (!expr->type) { 2531 ret = -ENOMEM; 2532 goto free; 2533 } 2534 2535 return expr; 2536 free: 2537 destroy_hist_field(expr, 0); 2538 return ERR_PTR(ret); 2539 } 2540 2541 /* 2542 * If the operands are var refs, return pointers the 2543 * variable(s) referenced in var1 and var2, else NULL. 2544 */ 2545 static int check_expr_operands(struct trace_array *tr, 2546 struct hist_field *operand1, 2547 struct hist_field *operand2, 2548 struct hist_field **var1, 2549 struct hist_field **var2) 2550 { 2551 unsigned long operand1_flags = operand1->flags; 2552 unsigned long operand2_flags = operand2->flags; 2553 2554 if ((operand1_flags & HIST_FIELD_FL_VAR_REF) || 2555 (operand1_flags & HIST_FIELD_FL_ALIAS)) { 2556 struct hist_field *var; 2557 2558 var = find_var_field(operand1->var.hist_data, operand1->name); 2559 if (!var) 2560 return -EINVAL; 2561 operand1_flags = var->flags; 2562 *var1 = var; 2563 } 2564 2565 if ((operand2_flags & HIST_FIELD_FL_VAR_REF) || 2566 (operand2_flags & HIST_FIELD_FL_ALIAS)) { 2567 struct hist_field *var; 2568 2569 var = find_var_field(operand2->var.hist_data, operand2->name); 2570 if (!var) 2571 return -EINVAL; 2572 operand2_flags = var->flags; 2573 *var2 = var; 2574 } 2575 2576 if ((operand1_flags & HIST_FIELD_FL_TIMESTAMP_USECS) != 2577 (operand2_flags & HIST_FIELD_FL_TIMESTAMP_USECS)) { 2578 hist_err(tr, HIST_ERR_TIMESTAMP_MISMATCH, 0); 2579 return -EINVAL; 2580 } 2581 2582 return 0; 2583 } 2584 2585 static struct hist_field *parse_expr(struct hist_trigger_data *hist_data, 2586 struct trace_event_file *file, 2587 char *str, unsigned long flags, 2588 char *var_name, unsigned int *n_subexprs) 2589 { 2590 struct hist_field *operand1 = NULL, *operand2 = NULL, *expr = NULL; 2591 struct hist_field *var1 = NULL, *var2 = NULL; 2592 unsigned long operand_flags, operand2_flags; 2593 int field_op, ret = -EINVAL; 2594 char *sep, *operand1_str; 2595 hist_field_fn_t op_fn; 2596 bool combine_consts; 2597 2598 if (*n_subexprs > 3) { 2599 hist_err(file->tr, HIST_ERR_TOO_MANY_SUBEXPR, errpos(str)); 2600 return ERR_PTR(-EINVAL); 2601 } 2602 2603 field_op = contains_operator(str, &sep); 2604 2605 if (field_op == FIELD_OP_NONE) 2606 return parse_atom(hist_data, file, str, &flags, var_name); 2607 2608 if (field_op == FIELD_OP_UNARY_MINUS) 2609 return parse_unary(hist_data, file, str, flags, var_name, n_subexprs); 2610 2611 /* Binary operator found, increment n_subexprs */ 2612 ++*n_subexprs; 2613 2614 /* Split the expression string at the root operator */ 2615 if (!sep) 2616 return ERR_PTR(-EINVAL); 2617 2618 *sep = '\0'; 2619 operand1_str = str; 2620 str = sep+1; 2621 2622 /* Binary operator requires both operands */ 2623 if (*operand1_str == '\0' || *str == '\0') 2624 return ERR_PTR(-EINVAL); 2625 2626 operand_flags = 0; 2627 2628 /* LHS of string is an expression e.g. a+b in a+b+c */ 2629 operand1 = parse_expr(hist_data, file, operand1_str, operand_flags, NULL, n_subexprs); 2630 if (IS_ERR(operand1)) 2631 return ERR_CAST(operand1); 2632 2633 if (operand1->flags & HIST_FIELD_FL_STRING) { 2634 hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(operand1_str)); 2635 ret = -EINVAL; 2636 goto free_op1; 2637 } 2638 2639 /* RHS of string is another expression e.g. c in a+b+c */ 2640 operand_flags = 0; 2641 operand2 = parse_expr(hist_data, file, str, operand_flags, NULL, n_subexprs); 2642 if (IS_ERR(operand2)) { 2643 ret = PTR_ERR(operand2); 2644 goto free_op1; 2645 } 2646 if (operand2->flags & HIST_FIELD_FL_STRING) { 2647 hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(str)); 2648 ret = -EINVAL; 2649 goto free_operands; 2650 } 2651 2652 switch (field_op) { 2653 case FIELD_OP_MINUS: 2654 op_fn = hist_field_minus; 2655 break; 2656 case FIELD_OP_PLUS: 2657 op_fn = hist_field_plus; 2658 break; 2659 case FIELD_OP_DIV: 2660 op_fn = hist_field_div; 2661 break; 2662 case FIELD_OP_MULT: 2663 op_fn = hist_field_mult; 2664 break; 2665 default: 2666 ret = -EINVAL; 2667 goto free_operands; 2668 } 2669 2670 ret = check_expr_operands(file->tr, operand1, operand2, &var1, &var2); 2671 if (ret) 2672 goto free_operands; 2673 2674 operand_flags = var1 ? var1->flags : operand1->flags; 2675 operand2_flags = var2 ? var2->flags : operand2->flags; 2676 2677 /* 2678 * If both operands are constant, the expression can be 2679 * collapsed to a single constant. 2680 */ 2681 combine_consts = operand_flags & operand2_flags & HIST_FIELD_FL_CONST; 2682 2683 flags |= combine_consts ? HIST_FIELD_FL_CONST : HIST_FIELD_FL_EXPR; 2684 2685 flags |= operand1->flags & 2686 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS); 2687 2688 expr = create_hist_field(hist_data, NULL, flags, var_name); 2689 if (!expr) { 2690 ret = -ENOMEM; 2691 goto free_operands; 2692 } 2693 2694 operand1->read_once = true; 2695 operand2->read_once = true; 2696 2697 /* The operands are now owned and free'd by 'expr' */ 2698 expr->operands[0] = operand1; 2699 expr->operands[1] = operand2; 2700 2701 if (field_op == FIELD_OP_DIV && 2702 operand2_flags & HIST_FIELD_FL_CONST) { 2703 u64 divisor = var2 ? var2->constant : operand2->constant; 2704 2705 if (!divisor) { 2706 hist_err(file->tr, HIST_ERR_DIVISION_BY_ZERO, errpos(str)); 2707 ret = -EDOM; 2708 goto free_expr; 2709 } 2710 2711 /* 2712 * Copy the divisor here so we don't have to look it up 2713 * later if this is a var ref 2714 */ 2715 operand2->constant = divisor; 2716 op_fn = hist_field_get_div_fn(operand2); 2717 } 2718 2719 if (combine_consts) { 2720 if (var1) 2721 expr->operands[0] = var1; 2722 if (var2) 2723 expr->operands[1] = var2; 2724 2725 expr->constant = op_fn(expr, NULL, NULL, NULL, NULL); 2726 2727 expr->operands[0] = NULL; 2728 expr->operands[1] = NULL; 2729 2730 /* 2731 * var refs won't be destroyed immediately 2732 * See: destroy_hist_field() 2733 */ 2734 destroy_hist_field(operand2, 0); 2735 destroy_hist_field(operand1, 0); 2736 2737 expr->name = expr_str(expr, 0); 2738 } else { 2739 expr->fn = op_fn; 2740 2741 /* The operand sizes should be the same, so just pick one */ 2742 expr->size = operand1->size; 2743 expr->is_signed = operand1->is_signed; 2744 2745 expr->operator = field_op; 2746 expr->type = kstrdup_const(operand1->type, GFP_KERNEL); 2747 if (!expr->type) { 2748 ret = -ENOMEM; 2749 goto free_expr; 2750 } 2751 2752 expr->name = expr_str(expr, 0); 2753 } 2754 2755 return expr; 2756 2757 free_operands: 2758 destroy_hist_field(operand2, 0); 2759 free_op1: 2760 destroy_hist_field(operand1, 0); 2761 return ERR_PTR(ret); 2762 2763 free_expr: 2764 destroy_hist_field(expr, 0); 2765 return ERR_PTR(ret); 2766 } 2767 2768 static char *find_trigger_filter(struct hist_trigger_data *hist_data, 2769 struct trace_event_file *file) 2770 { 2771 struct event_trigger_data *test; 2772 2773 lockdep_assert_held(&event_mutex); 2774 2775 list_for_each_entry(test, &file->triggers, list) { 2776 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 2777 if (test->private_data == hist_data) 2778 return test->filter_str; 2779 } 2780 } 2781 2782 return NULL; 2783 } 2784 2785 static struct event_command trigger_hist_cmd; 2786 static int event_hist_trigger_parse(struct event_command *cmd_ops, 2787 struct trace_event_file *file, 2788 char *glob, char *cmd, char *param); 2789 2790 static bool compatible_keys(struct hist_trigger_data *target_hist_data, 2791 struct hist_trigger_data *hist_data, 2792 unsigned int n_keys) 2793 { 2794 struct hist_field *target_hist_field, *hist_field; 2795 unsigned int n, i, j; 2796 2797 if (hist_data->n_fields - hist_data->n_vals != n_keys) 2798 return false; 2799 2800 i = hist_data->n_vals; 2801 j = target_hist_data->n_vals; 2802 2803 for (n = 0; n < n_keys; n++) { 2804 hist_field = hist_data->fields[i + n]; 2805 target_hist_field = target_hist_data->fields[j + n]; 2806 2807 if (strcmp(hist_field->type, target_hist_field->type) != 0) 2808 return false; 2809 if (hist_field->size != target_hist_field->size) 2810 return false; 2811 if (hist_field->is_signed != target_hist_field->is_signed) 2812 return false; 2813 } 2814 2815 return true; 2816 } 2817 2818 static struct hist_trigger_data * 2819 find_compatible_hist(struct hist_trigger_data *target_hist_data, 2820 struct trace_event_file *file) 2821 { 2822 struct hist_trigger_data *hist_data; 2823 struct event_trigger_data *test; 2824 unsigned int n_keys; 2825 2826 lockdep_assert_held(&event_mutex); 2827 2828 n_keys = target_hist_data->n_fields - target_hist_data->n_vals; 2829 2830 list_for_each_entry(test, &file->triggers, list) { 2831 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 2832 hist_data = test->private_data; 2833 2834 if (compatible_keys(target_hist_data, hist_data, n_keys)) 2835 return hist_data; 2836 } 2837 } 2838 2839 return NULL; 2840 } 2841 2842 static struct trace_event_file *event_file(struct trace_array *tr, 2843 char *system, char *event_name) 2844 { 2845 struct trace_event_file *file; 2846 2847 file = __find_event_file(tr, system, event_name); 2848 if (!file) 2849 return ERR_PTR(-EINVAL); 2850 2851 return file; 2852 } 2853 2854 static struct hist_field * 2855 find_synthetic_field_var(struct hist_trigger_data *target_hist_data, 2856 char *system, char *event_name, char *field_name) 2857 { 2858 struct hist_field *event_var; 2859 char *synthetic_name; 2860 2861 synthetic_name = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL); 2862 if (!synthetic_name) 2863 return ERR_PTR(-ENOMEM); 2864 2865 strcpy(synthetic_name, "synthetic_"); 2866 strcat(synthetic_name, field_name); 2867 2868 event_var = find_event_var(target_hist_data, system, event_name, synthetic_name); 2869 2870 kfree(synthetic_name); 2871 2872 return event_var; 2873 } 2874 2875 /** 2876 * create_field_var_hist - Automatically create a histogram and var for a field 2877 * @target_hist_data: The target hist trigger 2878 * @subsys_name: Optional subsystem name 2879 * @event_name: Optional event name 2880 * @field_name: The name of the field (and the resulting variable) 2881 * 2882 * Hist trigger actions fetch data from variables, not directly from 2883 * events. However, for convenience, users are allowed to directly 2884 * specify an event field in an action, which will be automatically 2885 * converted into a variable on their behalf. 2886 * 2887 * If a user specifies a field on an event that isn't the event the 2888 * histogram currently being defined (the target event histogram), the 2889 * only way that can be accomplished is if a new hist trigger is 2890 * created and the field variable defined on that. 2891 * 2892 * This function creates a new histogram compatible with the target 2893 * event (meaning a histogram with the same key as the target 2894 * histogram), and creates a variable for the specified field, but 2895 * with 'synthetic_' prepended to the variable name in order to avoid 2896 * collision with normal field variables. 2897 * 2898 * Return: The variable created for the field. 2899 */ 2900 static struct hist_field * 2901 create_field_var_hist(struct hist_trigger_data *target_hist_data, 2902 char *subsys_name, char *event_name, char *field_name) 2903 { 2904 struct trace_array *tr = target_hist_data->event_file->tr; 2905 struct hist_trigger_data *hist_data; 2906 unsigned int i, n, first = true; 2907 struct field_var_hist *var_hist; 2908 struct trace_event_file *file; 2909 struct hist_field *key_field; 2910 struct hist_field *event_var; 2911 char *saved_filter; 2912 char *cmd; 2913 int ret; 2914 2915 if (target_hist_data->n_field_var_hists >= SYNTH_FIELDS_MAX) { 2916 hist_err(tr, HIST_ERR_TOO_MANY_FIELD_VARS, errpos(field_name)); 2917 return ERR_PTR(-EINVAL); 2918 } 2919 2920 file = event_file(tr, subsys_name, event_name); 2921 2922 if (IS_ERR(file)) { 2923 hist_err(tr, HIST_ERR_EVENT_FILE_NOT_FOUND, errpos(field_name)); 2924 ret = PTR_ERR(file); 2925 return ERR_PTR(ret); 2926 } 2927 2928 /* 2929 * Look for a histogram compatible with target. We'll use the 2930 * found histogram specification to create a new matching 2931 * histogram with our variable on it. target_hist_data is not 2932 * yet a registered histogram so we can't use that. 2933 */ 2934 hist_data = find_compatible_hist(target_hist_data, file); 2935 if (!hist_data) { 2936 hist_err(tr, HIST_ERR_HIST_NOT_FOUND, errpos(field_name)); 2937 return ERR_PTR(-EINVAL); 2938 } 2939 2940 /* See if a synthetic field variable has already been created */ 2941 event_var = find_synthetic_field_var(target_hist_data, subsys_name, 2942 event_name, field_name); 2943 if (!IS_ERR_OR_NULL(event_var)) 2944 return event_var; 2945 2946 var_hist = kzalloc(sizeof(*var_hist), GFP_KERNEL); 2947 if (!var_hist) 2948 return ERR_PTR(-ENOMEM); 2949 2950 cmd = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL); 2951 if (!cmd) { 2952 kfree(var_hist); 2953 return ERR_PTR(-ENOMEM); 2954 } 2955 2956 /* Use the same keys as the compatible histogram */ 2957 strcat(cmd, "keys="); 2958 2959 for_each_hist_key_field(i, hist_data) { 2960 key_field = hist_data->fields[i]; 2961 if (!first) 2962 strcat(cmd, ","); 2963 strcat(cmd, key_field->field->name); 2964 first = false; 2965 } 2966 2967 /* Create the synthetic field variable specification */ 2968 strcat(cmd, ":synthetic_"); 2969 strcat(cmd, field_name); 2970 strcat(cmd, "="); 2971 strcat(cmd, field_name); 2972 2973 /* Use the same filter as the compatible histogram */ 2974 saved_filter = find_trigger_filter(hist_data, file); 2975 if (saved_filter) { 2976 strcat(cmd, " if "); 2977 strcat(cmd, saved_filter); 2978 } 2979 2980 var_hist->cmd = kstrdup(cmd, GFP_KERNEL); 2981 if (!var_hist->cmd) { 2982 kfree(cmd); 2983 kfree(var_hist); 2984 return ERR_PTR(-ENOMEM); 2985 } 2986 2987 /* Save the compatible histogram information */ 2988 var_hist->hist_data = hist_data; 2989 2990 /* Create the new histogram with our variable */ 2991 ret = event_hist_trigger_parse(&trigger_hist_cmd, file, 2992 "", "hist", cmd); 2993 if (ret) { 2994 kfree(cmd); 2995 kfree(var_hist->cmd); 2996 kfree(var_hist); 2997 hist_err(tr, HIST_ERR_HIST_CREATE_FAIL, errpos(field_name)); 2998 return ERR_PTR(ret); 2999 } 3000 3001 kfree(cmd); 3002 3003 /* If we can't find the variable, something went wrong */ 3004 event_var = find_synthetic_field_var(target_hist_data, subsys_name, 3005 event_name, field_name); 3006 if (IS_ERR_OR_NULL(event_var)) { 3007 kfree(var_hist->cmd); 3008 kfree(var_hist); 3009 hist_err(tr, HIST_ERR_SYNTH_VAR_NOT_FOUND, errpos(field_name)); 3010 return ERR_PTR(-EINVAL); 3011 } 3012 3013 n = target_hist_data->n_field_var_hists; 3014 target_hist_data->field_var_hists[n] = var_hist; 3015 target_hist_data->n_field_var_hists++; 3016 3017 return event_var; 3018 } 3019 3020 static struct hist_field * 3021 find_target_event_var(struct hist_trigger_data *hist_data, 3022 char *subsys_name, char *event_name, char *var_name) 3023 { 3024 struct trace_event_file *file = hist_data->event_file; 3025 struct hist_field *hist_field = NULL; 3026 3027 if (subsys_name) { 3028 struct trace_event_call *call; 3029 3030 if (!event_name) 3031 return NULL; 3032 3033 call = file->event_call; 3034 3035 if (strcmp(subsys_name, call->class->system) != 0) 3036 return NULL; 3037 3038 if (strcmp(event_name, trace_event_name(call)) != 0) 3039 return NULL; 3040 } 3041 3042 hist_field = find_var_field(hist_data, var_name); 3043 3044 return hist_field; 3045 } 3046 3047 static inline void __update_field_vars(struct tracing_map_elt *elt, 3048 struct trace_buffer *buffer, 3049 struct ring_buffer_event *rbe, 3050 void *rec, 3051 struct field_var **field_vars, 3052 unsigned int n_field_vars, 3053 unsigned int field_var_str_start) 3054 { 3055 struct hist_elt_data *elt_data = elt->private_data; 3056 unsigned int i, j, var_idx; 3057 u64 var_val; 3058 3059 for (i = 0, j = field_var_str_start; i < n_field_vars; i++) { 3060 struct field_var *field_var = field_vars[i]; 3061 struct hist_field *var = field_var->var; 3062 struct hist_field *val = field_var->val; 3063 3064 var_val = val->fn(val, elt, buffer, rbe, rec); 3065 var_idx = var->var.idx; 3066 3067 if (val->flags & HIST_FIELD_FL_STRING) { 3068 char *str = elt_data->field_var_str[j++]; 3069 char *val_str = (char *)(uintptr_t)var_val; 3070 unsigned int size; 3071 3072 size = min(val->size, STR_VAR_LEN_MAX); 3073 strscpy(str, val_str, size); 3074 var_val = (u64)(uintptr_t)str; 3075 } 3076 tracing_map_set_var(elt, var_idx, var_val); 3077 } 3078 } 3079 3080 static void update_field_vars(struct hist_trigger_data *hist_data, 3081 struct tracing_map_elt *elt, 3082 struct trace_buffer *buffer, 3083 struct ring_buffer_event *rbe, 3084 void *rec) 3085 { 3086 __update_field_vars(elt, buffer, rbe, rec, hist_data->field_vars, 3087 hist_data->n_field_vars, 0); 3088 } 3089 3090 static void save_track_data_vars(struct hist_trigger_data *hist_data, 3091 struct tracing_map_elt *elt, 3092 struct trace_buffer *buffer, void *rec, 3093 struct ring_buffer_event *rbe, void *key, 3094 struct action_data *data, u64 *var_ref_vals) 3095 { 3096 __update_field_vars(elt, buffer, rbe, rec, hist_data->save_vars, 3097 hist_data->n_save_vars, hist_data->n_field_var_str); 3098 } 3099 3100 static struct hist_field *create_var(struct hist_trigger_data *hist_data, 3101 struct trace_event_file *file, 3102 char *name, int size, const char *type) 3103 { 3104 struct hist_field *var; 3105 int idx; 3106 3107 if (find_var(hist_data, file, name) && !hist_data->remove) { 3108 var = ERR_PTR(-EINVAL); 3109 goto out; 3110 } 3111 3112 var = kzalloc(sizeof(struct hist_field), GFP_KERNEL); 3113 if (!var) { 3114 var = ERR_PTR(-ENOMEM); 3115 goto out; 3116 } 3117 3118 idx = tracing_map_add_var(hist_data->map); 3119 if (idx < 0) { 3120 kfree(var); 3121 var = ERR_PTR(-EINVAL); 3122 goto out; 3123 } 3124 3125 var->ref = 1; 3126 var->flags = HIST_FIELD_FL_VAR; 3127 var->var.idx = idx; 3128 var->var.hist_data = var->hist_data = hist_data; 3129 var->size = size; 3130 var->var.name = kstrdup(name, GFP_KERNEL); 3131 var->type = kstrdup_const(type, GFP_KERNEL); 3132 if (!var->var.name || !var->type) { 3133 kfree_const(var->type); 3134 kfree(var->var.name); 3135 kfree(var); 3136 var = ERR_PTR(-ENOMEM); 3137 } 3138 out: 3139 return var; 3140 } 3141 3142 static struct field_var *create_field_var(struct hist_trigger_data *hist_data, 3143 struct trace_event_file *file, 3144 char *field_name) 3145 { 3146 struct hist_field *val = NULL, *var = NULL; 3147 unsigned long flags = HIST_FIELD_FL_VAR; 3148 struct trace_array *tr = file->tr; 3149 struct field_var *field_var; 3150 int ret = 0; 3151 3152 if (hist_data->n_field_vars >= SYNTH_FIELDS_MAX) { 3153 hist_err(tr, HIST_ERR_TOO_MANY_FIELD_VARS, errpos(field_name)); 3154 ret = -EINVAL; 3155 goto err; 3156 } 3157 3158 val = parse_atom(hist_data, file, field_name, &flags, NULL); 3159 if (IS_ERR(val)) { 3160 hist_err(tr, HIST_ERR_FIELD_VAR_PARSE_FAIL, errpos(field_name)); 3161 ret = PTR_ERR(val); 3162 goto err; 3163 } 3164 3165 var = create_var(hist_data, file, field_name, val->size, val->type); 3166 if (IS_ERR(var)) { 3167 hist_err(tr, HIST_ERR_VAR_CREATE_FIND_FAIL, errpos(field_name)); 3168 kfree(val); 3169 ret = PTR_ERR(var); 3170 goto err; 3171 } 3172 3173 field_var = kzalloc(sizeof(struct field_var), GFP_KERNEL); 3174 if (!field_var) { 3175 kfree(val); 3176 kfree(var); 3177 ret = -ENOMEM; 3178 goto err; 3179 } 3180 3181 field_var->var = var; 3182 field_var->val = val; 3183 out: 3184 return field_var; 3185 err: 3186 field_var = ERR_PTR(ret); 3187 goto out; 3188 } 3189 3190 /** 3191 * create_target_field_var - Automatically create a variable for a field 3192 * @target_hist_data: The target hist trigger 3193 * @subsys_name: Optional subsystem name 3194 * @event_name: Optional event name 3195 * @var_name: The name of the field (and the resulting variable) 3196 * 3197 * Hist trigger actions fetch data from variables, not directly from 3198 * events. However, for convenience, users are allowed to directly 3199 * specify an event field in an action, which will be automatically 3200 * converted into a variable on their behalf. 3201 3202 * This function creates a field variable with the name var_name on 3203 * the hist trigger currently being defined on the target event. If 3204 * subsys_name and event_name are specified, this function simply 3205 * verifies that they do in fact match the target event subsystem and 3206 * event name. 3207 * 3208 * Return: The variable created for the field. 3209 */ 3210 static struct field_var * 3211 create_target_field_var(struct hist_trigger_data *target_hist_data, 3212 char *subsys_name, char *event_name, char *var_name) 3213 { 3214 struct trace_event_file *file = target_hist_data->event_file; 3215 3216 if (subsys_name) { 3217 struct trace_event_call *call; 3218 3219 if (!event_name) 3220 return NULL; 3221 3222 call = file->event_call; 3223 3224 if (strcmp(subsys_name, call->class->system) != 0) 3225 return NULL; 3226 3227 if (strcmp(event_name, trace_event_name(call)) != 0) 3228 return NULL; 3229 } 3230 3231 return create_field_var(target_hist_data, file, var_name); 3232 } 3233 3234 static bool check_track_val_max(u64 track_val, u64 var_val) 3235 { 3236 if (var_val <= track_val) 3237 return false; 3238 3239 return true; 3240 } 3241 3242 static bool check_track_val_changed(u64 track_val, u64 var_val) 3243 { 3244 if (var_val == track_val) 3245 return false; 3246 3247 return true; 3248 } 3249 3250 static u64 get_track_val(struct hist_trigger_data *hist_data, 3251 struct tracing_map_elt *elt, 3252 struct action_data *data) 3253 { 3254 unsigned int track_var_idx = data->track_data.track_var->var.idx; 3255 u64 track_val; 3256 3257 track_val = tracing_map_read_var(elt, track_var_idx); 3258 3259 return track_val; 3260 } 3261 3262 static void save_track_val(struct hist_trigger_data *hist_data, 3263 struct tracing_map_elt *elt, 3264 struct action_data *data, u64 var_val) 3265 { 3266 unsigned int track_var_idx = data->track_data.track_var->var.idx; 3267 3268 tracing_map_set_var(elt, track_var_idx, var_val); 3269 } 3270 3271 static void save_track_data(struct hist_trigger_data *hist_data, 3272 struct tracing_map_elt *elt, 3273 struct trace_buffer *buffer, void *rec, 3274 struct ring_buffer_event *rbe, void *key, 3275 struct action_data *data, u64 *var_ref_vals) 3276 { 3277 if (data->track_data.save_data) 3278 data->track_data.save_data(hist_data, elt, buffer, rec, rbe, 3279 key, data, var_ref_vals); 3280 } 3281 3282 static bool check_track_val(struct tracing_map_elt *elt, 3283 struct action_data *data, 3284 u64 var_val) 3285 { 3286 struct hist_trigger_data *hist_data; 3287 u64 track_val; 3288 3289 hist_data = data->track_data.track_var->hist_data; 3290 track_val = get_track_val(hist_data, elt, data); 3291 3292 return data->track_data.check_val(track_val, var_val); 3293 } 3294 3295 #ifdef CONFIG_TRACER_SNAPSHOT 3296 static bool cond_snapshot_update(struct trace_array *tr, void *cond_data) 3297 { 3298 /* called with tr->max_lock held */ 3299 struct track_data *track_data = tr->cond_snapshot->cond_data; 3300 struct hist_elt_data *elt_data, *track_elt_data; 3301 struct snapshot_context *context = cond_data; 3302 struct action_data *action; 3303 u64 track_val; 3304 3305 if (!track_data) 3306 return false; 3307 3308 action = track_data->action_data; 3309 3310 track_val = get_track_val(track_data->hist_data, context->elt, 3311 track_data->action_data); 3312 3313 if (!action->track_data.check_val(track_data->track_val, track_val)) 3314 return false; 3315 3316 track_data->track_val = track_val; 3317 memcpy(track_data->key, context->key, track_data->key_len); 3318 3319 elt_data = context->elt->private_data; 3320 track_elt_data = track_data->elt.private_data; 3321 if (elt_data->comm) 3322 strncpy(track_elt_data->comm, elt_data->comm, TASK_COMM_LEN); 3323 3324 track_data->updated = true; 3325 3326 return true; 3327 } 3328 3329 static void save_track_data_snapshot(struct hist_trigger_data *hist_data, 3330 struct tracing_map_elt *elt, 3331 struct trace_buffer *buffer, void *rec, 3332 struct ring_buffer_event *rbe, void *key, 3333 struct action_data *data, 3334 u64 *var_ref_vals) 3335 { 3336 struct trace_event_file *file = hist_data->event_file; 3337 struct snapshot_context context; 3338 3339 context.elt = elt; 3340 context.key = key; 3341 3342 tracing_snapshot_cond(file->tr, &context); 3343 } 3344 3345 static void hist_trigger_print_key(struct seq_file *m, 3346 struct hist_trigger_data *hist_data, 3347 void *key, 3348 struct tracing_map_elt *elt); 3349 3350 static struct action_data *snapshot_action(struct hist_trigger_data *hist_data) 3351 { 3352 unsigned int i; 3353 3354 if (!hist_data->n_actions) 3355 return NULL; 3356 3357 for (i = 0; i < hist_data->n_actions; i++) { 3358 struct action_data *data = hist_data->actions[i]; 3359 3360 if (data->action == ACTION_SNAPSHOT) 3361 return data; 3362 } 3363 3364 return NULL; 3365 } 3366 3367 static void track_data_snapshot_print(struct seq_file *m, 3368 struct hist_trigger_data *hist_data) 3369 { 3370 struct trace_event_file *file = hist_data->event_file; 3371 struct track_data *track_data; 3372 struct action_data *action; 3373 3374 track_data = tracing_cond_snapshot_data(file->tr); 3375 if (!track_data) 3376 return; 3377 3378 if (!track_data->updated) 3379 return; 3380 3381 action = snapshot_action(hist_data); 3382 if (!action) 3383 return; 3384 3385 seq_puts(m, "\nSnapshot taken (see tracing/snapshot). Details:\n"); 3386 seq_printf(m, "\ttriggering value { %s(%s) }: %10llu", 3387 action->handler == HANDLER_ONMAX ? "onmax" : "onchange", 3388 action->track_data.var_str, track_data->track_val); 3389 3390 seq_puts(m, "\ttriggered by event with key: "); 3391 hist_trigger_print_key(m, hist_data, track_data->key, &track_data->elt); 3392 seq_putc(m, '\n'); 3393 } 3394 #else 3395 static bool cond_snapshot_update(struct trace_array *tr, void *cond_data) 3396 { 3397 return false; 3398 } 3399 static void save_track_data_snapshot(struct hist_trigger_data *hist_data, 3400 struct tracing_map_elt *elt, 3401 struct trace_buffer *buffer, void *rec, 3402 struct ring_buffer_event *rbe, void *key, 3403 struct action_data *data, 3404 u64 *var_ref_vals) {} 3405 static void track_data_snapshot_print(struct seq_file *m, 3406 struct hist_trigger_data *hist_data) {} 3407 #endif /* CONFIG_TRACER_SNAPSHOT */ 3408 3409 static void track_data_print(struct seq_file *m, 3410 struct hist_trigger_data *hist_data, 3411 struct tracing_map_elt *elt, 3412 struct action_data *data) 3413 { 3414 u64 track_val = get_track_val(hist_data, elt, data); 3415 unsigned int i, save_var_idx; 3416 3417 if (data->handler == HANDLER_ONMAX) 3418 seq_printf(m, "\n\tmax: %10llu", track_val); 3419 else if (data->handler == HANDLER_ONCHANGE) 3420 seq_printf(m, "\n\tchanged: %10llu", track_val); 3421 3422 if (data->action == ACTION_SNAPSHOT) 3423 return; 3424 3425 for (i = 0; i < hist_data->n_save_vars; i++) { 3426 struct hist_field *save_val = hist_data->save_vars[i]->val; 3427 struct hist_field *save_var = hist_data->save_vars[i]->var; 3428 u64 val; 3429 3430 save_var_idx = save_var->var.idx; 3431 3432 val = tracing_map_read_var(elt, save_var_idx); 3433 3434 if (save_val->flags & HIST_FIELD_FL_STRING) { 3435 seq_printf(m, " %s: %-32s", save_var->var.name, 3436 (char *)(uintptr_t)(val)); 3437 } else 3438 seq_printf(m, " %s: %10llu", save_var->var.name, val); 3439 } 3440 } 3441 3442 static void ontrack_action(struct hist_trigger_data *hist_data, 3443 struct tracing_map_elt *elt, 3444 struct trace_buffer *buffer, void *rec, 3445 struct ring_buffer_event *rbe, void *key, 3446 struct action_data *data, u64 *var_ref_vals) 3447 { 3448 u64 var_val = var_ref_vals[data->track_data.var_ref->var_ref_idx]; 3449 3450 if (check_track_val(elt, data, var_val)) { 3451 save_track_val(hist_data, elt, data, var_val); 3452 save_track_data(hist_data, elt, buffer, rec, rbe, 3453 key, data, var_ref_vals); 3454 } 3455 } 3456 3457 static void action_data_destroy(struct action_data *data) 3458 { 3459 unsigned int i; 3460 3461 lockdep_assert_held(&event_mutex); 3462 3463 kfree(data->action_name); 3464 3465 for (i = 0; i < data->n_params; i++) 3466 kfree(data->params[i]); 3467 3468 if (data->synth_event) 3469 data->synth_event->ref--; 3470 3471 kfree(data->synth_event_name); 3472 3473 kfree(data); 3474 } 3475 3476 static void track_data_destroy(struct hist_trigger_data *hist_data, 3477 struct action_data *data) 3478 { 3479 struct trace_event_file *file = hist_data->event_file; 3480 3481 destroy_hist_field(data->track_data.track_var, 0); 3482 3483 if (data->action == ACTION_SNAPSHOT) { 3484 struct track_data *track_data; 3485 3486 track_data = tracing_cond_snapshot_data(file->tr); 3487 if (track_data && track_data->hist_data == hist_data) { 3488 tracing_snapshot_cond_disable(file->tr); 3489 track_data_free(track_data); 3490 } 3491 } 3492 3493 kfree(data->track_data.var_str); 3494 3495 action_data_destroy(data); 3496 } 3497 3498 static int action_create(struct hist_trigger_data *hist_data, 3499 struct action_data *data); 3500 3501 static int track_data_create(struct hist_trigger_data *hist_data, 3502 struct action_data *data) 3503 { 3504 struct hist_field *var_field, *ref_field, *track_var = NULL; 3505 struct trace_event_file *file = hist_data->event_file; 3506 struct trace_array *tr = file->tr; 3507 char *track_data_var_str; 3508 int ret = 0; 3509 3510 track_data_var_str = data->track_data.var_str; 3511 if (track_data_var_str[0] != '$') { 3512 hist_err(tr, HIST_ERR_ONX_NOT_VAR, errpos(track_data_var_str)); 3513 return -EINVAL; 3514 } 3515 track_data_var_str++; 3516 3517 var_field = find_target_event_var(hist_data, NULL, NULL, track_data_var_str); 3518 if (!var_field) { 3519 hist_err(tr, HIST_ERR_ONX_VAR_NOT_FOUND, errpos(track_data_var_str)); 3520 return -EINVAL; 3521 } 3522 3523 ref_field = create_var_ref(hist_data, var_field, NULL, NULL); 3524 if (!ref_field) 3525 return -ENOMEM; 3526 3527 data->track_data.var_ref = ref_field; 3528 3529 if (data->handler == HANDLER_ONMAX) 3530 track_var = create_var(hist_data, file, "__max", sizeof(u64), "u64"); 3531 if (IS_ERR(track_var)) { 3532 hist_err(tr, HIST_ERR_ONX_VAR_CREATE_FAIL, 0); 3533 ret = PTR_ERR(track_var); 3534 goto out; 3535 } 3536 3537 if (data->handler == HANDLER_ONCHANGE) 3538 track_var = create_var(hist_data, file, "__change", sizeof(u64), "u64"); 3539 if (IS_ERR(track_var)) { 3540 hist_err(tr, HIST_ERR_ONX_VAR_CREATE_FAIL, 0); 3541 ret = PTR_ERR(track_var); 3542 goto out; 3543 } 3544 data->track_data.track_var = track_var; 3545 3546 ret = action_create(hist_data, data); 3547 out: 3548 return ret; 3549 } 3550 3551 static int parse_action_params(struct trace_array *tr, char *params, 3552 struct action_data *data) 3553 { 3554 char *param, *saved_param; 3555 bool first_param = true; 3556 int ret = 0; 3557 3558 while (params) { 3559 if (data->n_params >= SYNTH_FIELDS_MAX) { 3560 hist_err(tr, HIST_ERR_TOO_MANY_PARAMS, 0); 3561 goto out; 3562 } 3563 3564 param = strsep(¶ms, ","); 3565 if (!param) { 3566 hist_err(tr, HIST_ERR_PARAM_NOT_FOUND, 0); 3567 ret = -EINVAL; 3568 goto out; 3569 } 3570 3571 param = strstrip(param); 3572 if (strlen(param) < 2) { 3573 hist_err(tr, HIST_ERR_INVALID_PARAM, errpos(param)); 3574 ret = -EINVAL; 3575 goto out; 3576 } 3577 3578 saved_param = kstrdup(param, GFP_KERNEL); 3579 if (!saved_param) { 3580 ret = -ENOMEM; 3581 goto out; 3582 } 3583 3584 if (first_param && data->use_trace_keyword) { 3585 data->synth_event_name = saved_param; 3586 first_param = false; 3587 continue; 3588 } 3589 first_param = false; 3590 3591 data->params[data->n_params++] = saved_param; 3592 } 3593 out: 3594 return ret; 3595 } 3596 3597 static int action_parse(struct trace_array *tr, char *str, struct action_data *data, 3598 enum handler_id handler) 3599 { 3600 char *action_name; 3601 int ret = 0; 3602 3603 strsep(&str, "."); 3604 if (!str) { 3605 hist_err(tr, HIST_ERR_ACTION_NOT_FOUND, 0); 3606 ret = -EINVAL; 3607 goto out; 3608 } 3609 3610 action_name = strsep(&str, "("); 3611 if (!action_name || !str) { 3612 hist_err(tr, HIST_ERR_ACTION_NOT_FOUND, 0); 3613 ret = -EINVAL; 3614 goto out; 3615 } 3616 3617 if (str_has_prefix(action_name, "save")) { 3618 char *params = strsep(&str, ")"); 3619 3620 if (!params) { 3621 hist_err(tr, HIST_ERR_NO_SAVE_PARAMS, 0); 3622 ret = -EINVAL; 3623 goto out; 3624 } 3625 3626 ret = parse_action_params(tr, params, data); 3627 if (ret) 3628 goto out; 3629 3630 if (handler == HANDLER_ONMAX) 3631 data->track_data.check_val = check_track_val_max; 3632 else if (handler == HANDLER_ONCHANGE) 3633 data->track_data.check_val = check_track_val_changed; 3634 else { 3635 hist_err(tr, HIST_ERR_ACTION_MISMATCH, errpos(action_name)); 3636 ret = -EINVAL; 3637 goto out; 3638 } 3639 3640 data->track_data.save_data = save_track_data_vars; 3641 data->fn = ontrack_action; 3642 data->action = ACTION_SAVE; 3643 } else if (str_has_prefix(action_name, "snapshot")) { 3644 char *params = strsep(&str, ")"); 3645 3646 if (!str) { 3647 hist_err(tr, HIST_ERR_NO_CLOSING_PAREN, errpos(params)); 3648 ret = -EINVAL; 3649 goto out; 3650 } 3651 3652 if (handler == HANDLER_ONMAX) 3653 data->track_data.check_val = check_track_val_max; 3654 else if (handler == HANDLER_ONCHANGE) 3655 data->track_data.check_val = check_track_val_changed; 3656 else { 3657 hist_err(tr, HIST_ERR_ACTION_MISMATCH, errpos(action_name)); 3658 ret = -EINVAL; 3659 goto out; 3660 } 3661 3662 data->track_data.save_data = save_track_data_snapshot; 3663 data->fn = ontrack_action; 3664 data->action = ACTION_SNAPSHOT; 3665 } else { 3666 char *params = strsep(&str, ")"); 3667 3668 if (str_has_prefix(action_name, "trace")) 3669 data->use_trace_keyword = true; 3670 3671 if (params) { 3672 ret = parse_action_params(tr, params, data); 3673 if (ret) 3674 goto out; 3675 } 3676 3677 if (handler == HANDLER_ONMAX) 3678 data->track_data.check_val = check_track_val_max; 3679 else if (handler == HANDLER_ONCHANGE) 3680 data->track_data.check_val = check_track_val_changed; 3681 3682 if (handler != HANDLER_ONMATCH) { 3683 data->track_data.save_data = action_trace; 3684 data->fn = ontrack_action; 3685 } else 3686 data->fn = action_trace; 3687 3688 data->action = ACTION_TRACE; 3689 } 3690 3691 data->action_name = kstrdup(action_name, GFP_KERNEL); 3692 if (!data->action_name) { 3693 ret = -ENOMEM; 3694 goto out; 3695 } 3696 3697 data->handler = handler; 3698 out: 3699 return ret; 3700 } 3701 3702 static struct action_data *track_data_parse(struct hist_trigger_data *hist_data, 3703 char *str, enum handler_id handler) 3704 { 3705 struct action_data *data; 3706 int ret = -EINVAL; 3707 char *var_str; 3708 3709 data = kzalloc(sizeof(*data), GFP_KERNEL); 3710 if (!data) 3711 return ERR_PTR(-ENOMEM); 3712 3713 var_str = strsep(&str, ")"); 3714 if (!var_str || !str) { 3715 ret = -EINVAL; 3716 goto free; 3717 } 3718 3719 data->track_data.var_str = kstrdup(var_str, GFP_KERNEL); 3720 if (!data->track_data.var_str) { 3721 ret = -ENOMEM; 3722 goto free; 3723 } 3724 3725 ret = action_parse(hist_data->event_file->tr, str, data, handler); 3726 if (ret) 3727 goto free; 3728 out: 3729 return data; 3730 free: 3731 track_data_destroy(hist_data, data); 3732 data = ERR_PTR(ret); 3733 goto out; 3734 } 3735 3736 static void onmatch_destroy(struct action_data *data) 3737 { 3738 kfree(data->match_data.event); 3739 kfree(data->match_data.event_system); 3740 3741 action_data_destroy(data); 3742 } 3743 3744 static void destroy_field_var(struct field_var *field_var) 3745 { 3746 if (!field_var) 3747 return; 3748 3749 destroy_hist_field(field_var->var, 0); 3750 destroy_hist_field(field_var->val, 0); 3751 3752 kfree(field_var); 3753 } 3754 3755 static void destroy_field_vars(struct hist_trigger_data *hist_data) 3756 { 3757 unsigned int i; 3758 3759 for (i = 0; i < hist_data->n_field_vars; i++) 3760 destroy_field_var(hist_data->field_vars[i]); 3761 3762 for (i = 0; i < hist_data->n_save_vars; i++) 3763 destroy_field_var(hist_data->save_vars[i]); 3764 } 3765 3766 static void save_field_var(struct hist_trigger_data *hist_data, 3767 struct field_var *field_var) 3768 { 3769 hist_data->field_vars[hist_data->n_field_vars++] = field_var; 3770 3771 if (field_var->val->flags & HIST_FIELD_FL_STRING) 3772 hist_data->n_field_var_str++; 3773 } 3774 3775 3776 static int check_synth_field(struct synth_event *event, 3777 struct hist_field *hist_field, 3778 unsigned int field_pos) 3779 { 3780 struct synth_field *field; 3781 3782 if (field_pos >= event->n_fields) 3783 return -EINVAL; 3784 3785 field = event->fields[field_pos]; 3786 3787 /* 3788 * A dynamic string synth field can accept static or 3789 * dynamic. A static string synth field can only accept a 3790 * same-sized static string, which is checked for later. 3791 */ 3792 if (strstr(hist_field->type, "char[") && field->is_string 3793 && field->is_dynamic) 3794 return 0; 3795 3796 if (strcmp(field->type, hist_field->type) != 0) { 3797 if (field->size != hist_field->size || 3798 (!field->is_string && field->is_signed != hist_field->is_signed)) 3799 return -EINVAL; 3800 } 3801 3802 return 0; 3803 } 3804 3805 static struct hist_field * 3806 trace_action_find_var(struct hist_trigger_data *hist_data, 3807 struct action_data *data, 3808 char *system, char *event, char *var) 3809 { 3810 struct trace_array *tr = hist_data->event_file->tr; 3811 struct hist_field *hist_field; 3812 3813 var++; /* skip '$' */ 3814 3815 hist_field = find_target_event_var(hist_data, system, event, var); 3816 if (!hist_field) { 3817 if (!system && data->handler == HANDLER_ONMATCH) { 3818 system = data->match_data.event_system; 3819 event = data->match_data.event; 3820 } 3821 3822 hist_field = find_event_var(hist_data, system, event, var); 3823 } 3824 3825 if (!hist_field) 3826 hist_err(tr, HIST_ERR_PARAM_NOT_FOUND, errpos(var)); 3827 3828 return hist_field; 3829 } 3830 3831 static struct hist_field * 3832 trace_action_create_field_var(struct hist_trigger_data *hist_data, 3833 struct action_data *data, char *system, 3834 char *event, char *var) 3835 { 3836 struct hist_field *hist_field = NULL; 3837 struct field_var *field_var; 3838 3839 /* 3840 * First try to create a field var on the target event (the 3841 * currently being defined). This will create a variable for 3842 * unqualified fields on the target event, or if qualified, 3843 * target fields that have qualified names matching the target. 3844 */ 3845 field_var = create_target_field_var(hist_data, system, event, var); 3846 3847 if (field_var && !IS_ERR(field_var)) { 3848 save_field_var(hist_data, field_var); 3849 hist_field = field_var->var; 3850 } else { 3851 field_var = NULL; 3852 /* 3853 * If no explicit system.event is specified, default to 3854 * looking for fields on the onmatch(system.event.xxx) 3855 * event. 3856 */ 3857 if (!system && data->handler == HANDLER_ONMATCH) { 3858 system = data->match_data.event_system; 3859 event = data->match_data.event; 3860 } 3861 3862 if (!event) 3863 goto free; 3864 /* 3865 * At this point, we're looking at a field on another 3866 * event. Because we can't modify a hist trigger on 3867 * another event to add a variable for a field, we need 3868 * to create a new trigger on that event and create the 3869 * variable at the same time. 3870 */ 3871 hist_field = create_field_var_hist(hist_data, system, event, var); 3872 if (IS_ERR(hist_field)) 3873 goto free; 3874 } 3875 out: 3876 return hist_field; 3877 free: 3878 destroy_field_var(field_var); 3879 hist_field = NULL; 3880 goto out; 3881 } 3882 3883 static int trace_action_create(struct hist_trigger_data *hist_data, 3884 struct action_data *data) 3885 { 3886 struct trace_array *tr = hist_data->event_file->tr; 3887 char *event_name, *param, *system = NULL; 3888 struct hist_field *hist_field, *var_ref; 3889 unsigned int i; 3890 unsigned int field_pos = 0; 3891 struct synth_event *event; 3892 char *synth_event_name; 3893 int var_ref_idx, ret = 0; 3894 3895 lockdep_assert_held(&event_mutex); 3896 3897 if (data->use_trace_keyword) 3898 synth_event_name = data->synth_event_name; 3899 else 3900 synth_event_name = data->action_name; 3901 3902 event = find_synth_event(synth_event_name); 3903 if (!event) { 3904 hist_err(tr, HIST_ERR_SYNTH_EVENT_NOT_FOUND, errpos(synth_event_name)); 3905 return -EINVAL; 3906 } 3907 3908 event->ref++; 3909 3910 for (i = 0; i < data->n_params; i++) { 3911 char *p; 3912 3913 p = param = kstrdup(data->params[i], GFP_KERNEL); 3914 if (!param) { 3915 ret = -ENOMEM; 3916 goto err; 3917 } 3918 3919 system = strsep(¶m, "."); 3920 if (!param) { 3921 param = (char *)system; 3922 system = event_name = NULL; 3923 } else { 3924 event_name = strsep(¶m, "."); 3925 if (!param) { 3926 kfree(p); 3927 ret = -EINVAL; 3928 goto err; 3929 } 3930 } 3931 3932 if (param[0] == '$') 3933 hist_field = trace_action_find_var(hist_data, data, 3934 system, event_name, 3935 param); 3936 else 3937 hist_field = trace_action_create_field_var(hist_data, 3938 data, 3939 system, 3940 event_name, 3941 param); 3942 3943 if (!hist_field) { 3944 kfree(p); 3945 ret = -EINVAL; 3946 goto err; 3947 } 3948 3949 if (check_synth_field(event, hist_field, field_pos) == 0) { 3950 var_ref = create_var_ref(hist_data, hist_field, 3951 system, event_name); 3952 if (!var_ref) { 3953 kfree(p); 3954 ret = -ENOMEM; 3955 goto err; 3956 } 3957 3958 var_ref_idx = find_var_ref_idx(hist_data, var_ref); 3959 if (WARN_ON(var_ref_idx < 0)) { 3960 kfree(p); 3961 ret = var_ref_idx; 3962 goto err; 3963 } 3964 3965 data->var_ref_idx[i] = var_ref_idx; 3966 3967 field_pos++; 3968 kfree(p); 3969 continue; 3970 } 3971 3972 hist_err(tr, HIST_ERR_SYNTH_TYPE_MISMATCH, errpos(param)); 3973 kfree(p); 3974 ret = -EINVAL; 3975 goto err; 3976 } 3977 3978 if (field_pos != event->n_fields) { 3979 hist_err(tr, HIST_ERR_SYNTH_COUNT_MISMATCH, errpos(event->name)); 3980 ret = -EINVAL; 3981 goto err; 3982 } 3983 3984 data->synth_event = event; 3985 out: 3986 return ret; 3987 err: 3988 event->ref--; 3989 3990 goto out; 3991 } 3992 3993 static int action_create(struct hist_trigger_data *hist_data, 3994 struct action_data *data) 3995 { 3996 struct trace_event_file *file = hist_data->event_file; 3997 struct trace_array *tr = file->tr; 3998 struct track_data *track_data; 3999 struct field_var *field_var; 4000 unsigned int i; 4001 char *param; 4002 int ret = 0; 4003 4004 if (data->action == ACTION_TRACE) 4005 return trace_action_create(hist_data, data); 4006 4007 if (data->action == ACTION_SNAPSHOT) { 4008 track_data = track_data_alloc(hist_data->key_size, data, hist_data); 4009 if (IS_ERR(track_data)) { 4010 ret = PTR_ERR(track_data); 4011 goto out; 4012 } 4013 4014 ret = tracing_snapshot_cond_enable(file->tr, track_data, 4015 cond_snapshot_update); 4016 if (ret) 4017 track_data_free(track_data); 4018 4019 goto out; 4020 } 4021 4022 if (data->action == ACTION_SAVE) { 4023 if (hist_data->n_save_vars) { 4024 ret = -EEXIST; 4025 hist_err(tr, HIST_ERR_TOO_MANY_SAVE_ACTIONS, 0); 4026 goto out; 4027 } 4028 4029 for (i = 0; i < data->n_params; i++) { 4030 param = kstrdup(data->params[i], GFP_KERNEL); 4031 if (!param) { 4032 ret = -ENOMEM; 4033 goto out; 4034 } 4035 4036 field_var = create_target_field_var(hist_data, NULL, NULL, param); 4037 if (IS_ERR(field_var)) { 4038 hist_err(tr, HIST_ERR_FIELD_VAR_CREATE_FAIL, 4039 errpos(param)); 4040 ret = PTR_ERR(field_var); 4041 kfree(param); 4042 goto out; 4043 } 4044 4045 hist_data->save_vars[hist_data->n_save_vars++] = field_var; 4046 if (field_var->val->flags & HIST_FIELD_FL_STRING) 4047 hist_data->n_save_var_str++; 4048 kfree(param); 4049 } 4050 } 4051 out: 4052 return ret; 4053 } 4054 4055 static int onmatch_create(struct hist_trigger_data *hist_data, 4056 struct action_data *data) 4057 { 4058 return action_create(hist_data, data); 4059 } 4060 4061 static struct action_data *onmatch_parse(struct trace_array *tr, char *str) 4062 { 4063 char *match_event, *match_event_system; 4064 struct action_data *data; 4065 int ret = -EINVAL; 4066 4067 data = kzalloc(sizeof(*data), GFP_KERNEL); 4068 if (!data) 4069 return ERR_PTR(-ENOMEM); 4070 4071 match_event = strsep(&str, ")"); 4072 if (!match_event || !str) { 4073 hist_err(tr, HIST_ERR_NO_CLOSING_PAREN, errpos(match_event)); 4074 goto free; 4075 } 4076 4077 match_event_system = strsep(&match_event, "."); 4078 if (!match_event) { 4079 hist_err(tr, HIST_ERR_SUBSYS_NOT_FOUND, errpos(match_event_system)); 4080 goto free; 4081 } 4082 4083 if (IS_ERR(event_file(tr, match_event_system, match_event))) { 4084 hist_err(tr, HIST_ERR_INVALID_SUBSYS_EVENT, errpos(match_event)); 4085 goto free; 4086 } 4087 4088 data->match_data.event = kstrdup(match_event, GFP_KERNEL); 4089 if (!data->match_data.event) { 4090 ret = -ENOMEM; 4091 goto free; 4092 } 4093 4094 data->match_data.event_system = kstrdup(match_event_system, GFP_KERNEL); 4095 if (!data->match_data.event_system) { 4096 ret = -ENOMEM; 4097 goto free; 4098 } 4099 4100 ret = action_parse(tr, str, data, HANDLER_ONMATCH); 4101 if (ret) 4102 goto free; 4103 out: 4104 return data; 4105 free: 4106 onmatch_destroy(data); 4107 data = ERR_PTR(ret); 4108 goto out; 4109 } 4110 4111 static int create_hitcount_val(struct hist_trigger_data *hist_data) 4112 { 4113 hist_data->fields[HITCOUNT_IDX] = 4114 create_hist_field(hist_data, NULL, HIST_FIELD_FL_HITCOUNT, NULL); 4115 if (!hist_data->fields[HITCOUNT_IDX]) 4116 return -ENOMEM; 4117 4118 hist_data->n_vals++; 4119 hist_data->n_fields++; 4120 4121 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX)) 4122 return -EINVAL; 4123 4124 return 0; 4125 } 4126 4127 static int __create_val_field(struct hist_trigger_data *hist_data, 4128 unsigned int val_idx, 4129 struct trace_event_file *file, 4130 char *var_name, char *field_str, 4131 unsigned long flags) 4132 { 4133 struct hist_field *hist_field; 4134 int ret = 0, n_subexprs = 0; 4135 4136 hist_field = parse_expr(hist_data, file, field_str, flags, var_name, &n_subexprs); 4137 if (IS_ERR(hist_field)) { 4138 ret = PTR_ERR(hist_field); 4139 goto out; 4140 } 4141 4142 hist_data->fields[val_idx] = hist_field; 4143 4144 ++hist_data->n_vals; 4145 ++hist_data->n_fields; 4146 4147 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX)) 4148 ret = -EINVAL; 4149 out: 4150 return ret; 4151 } 4152 4153 static int create_val_field(struct hist_trigger_data *hist_data, 4154 unsigned int val_idx, 4155 struct trace_event_file *file, 4156 char *field_str) 4157 { 4158 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX)) 4159 return -EINVAL; 4160 4161 return __create_val_field(hist_data, val_idx, file, NULL, field_str, 0); 4162 } 4163 4164 static const char *no_comm = "(no comm)"; 4165 4166 static u64 hist_field_execname(struct hist_field *hist_field, 4167 struct tracing_map_elt *elt, 4168 struct trace_buffer *buffer, 4169 struct ring_buffer_event *rbe, 4170 void *event) 4171 { 4172 struct hist_elt_data *elt_data; 4173 4174 if (WARN_ON_ONCE(!elt)) 4175 return (u64)(unsigned long)no_comm; 4176 4177 elt_data = elt->private_data; 4178 4179 if (WARN_ON_ONCE(!elt_data->comm)) 4180 return (u64)(unsigned long)no_comm; 4181 4182 return (u64)(unsigned long)(elt_data->comm); 4183 } 4184 4185 /* Convert a var that points to common_pid.execname to a string */ 4186 static void update_var_execname(struct hist_field *hist_field) 4187 { 4188 hist_field->flags = HIST_FIELD_FL_STRING | HIST_FIELD_FL_VAR | 4189 HIST_FIELD_FL_EXECNAME; 4190 hist_field->size = MAX_FILTER_STR_VAL; 4191 hist_field->is_signed = 0; 4192 4193 kfree_const(hist_field->type); 4194 hist_field->type = "char[]"; 4195 4196 hist_field->fn = hist_field_execname; 4197 } 4198 4199 static int create_var_field(struct hist_trigger_data *hist_data, 4200 unsigned int val_idx, 4201 struct trace_event_file *file, 4202 char *var_name, char *expr_str) 4203 { 4204 struct trace_array *tr = hist_data->event_file->tr; 4205 unsigned long flags = 0; 4206 int ret; 4207 4208 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX)) 4209 return -EINVAL; 4210 4211 if (find_var(hist_data, file, var_name) && !hist_data->remove) { 4212 hist_err(tr, HIST_ERR_DUPLICATE_VAR, errpos(var_name)); 4213 return -EINVAL; 4214 } 4215 4216 flags |= HIST_FIELD_FL_VAR; 4217 hist_data->n_vars++; 4218 if (WARN_ON(hist_data->n_vars > TRACING_MAP_VARS_MAX)) 4219 return -EINVAL; 4220 4221 ret = __create_val_field(hist_data, val_idx, file, var_name, expr_str, flags); 4222 4223 if (!ret && hist_data->fields[val_idx]->flags & HIST_FIELD_FL_EXECNAME) 4224 update_var_execname(hist_data->fields[val_idx]); 4225 4226 if (!ret && hist_data->fields[val_idx]->flags & HIST_FIELD_FL_STRING) 4227 hist_data->fields[val_idx]->var_str_idx = hist_data->n_var_str++; 4228 4229 return ret; 4230 } 4231 4232 static int create_val_fields(struct hist_trigger_data *hist_data, 4233 struct trace_event_file *file) 4234 { 4235 char *fields_str, *field_str; 4236 unsigned int i, j = 1; 4237 int ret; 4238 4239 ret = create_hitcount_val(hist_data); 4240 if (ret) 4241 goto out; 4242 4243 fields_str = hist_data->attrs->vals_str; 4244 if (!fields_str) 4245 goto out; 4246 4247 for (i = 0, j = 1; i < TRACING_MAP_VALS_MAX && 4248 j < TRACING_MAP_VALS_MAX; i++) { 4249 field_str = strsep(&fields_str, ","); 4250 if (!field_str) 4251 break; 4252 4253 if (strcmp(field_str, "hitcount") == 0) 4254 continue; 4255 4256 ret = create_val_field(hist_data, j++, file, field_str); 4257 if (ret) 4258 goto out; 4259 } 4260 4261 if (fields_str && (strcmp(fields_str, "hitcount") != 0)) 4262 ret = -EINVAL; 4263 out: 4264 return ret; 4265 } 4266 4267 static int create_key_field(struct hist_trigger_data *hist_data, 4268 unsigned int key_idx, 4269 unsigned int key_offset, 4270 struct trace_event_file *file, 4271 char *field_str) 4272 { 4273 struct trace_array *tr = hist_data->event_file->tr; 4274 struct hist_field *hist_field = NULL; 4275 unsigned long flags = 0; 4276 unsigned int key_size; 4277 int ret = 0, n_subexprs = 0; 4278 4279 if (WARN_ON(key_idx >= HIST_FIELDS_MAX)) 4280 return -EINVAL; 4281 4282 flags |= HIST_FIELD_FL_KEY; 4283 4284 if (strcmp(field_str, "stacktrace") == 0) { 4285 flags |= HIST_FIELD_FL_STACKTRACE; 4286 key_size = sizeof(unsigned long) * HIST_STACKTRACE_DEPTH; 4287 hist_field = create_hist_field(hist_data, NULL, flags, NULL); 4288 } else { 4289 hist_field = parse_expr(hist_data, file, field_str, flags, 4290 NULL, &n_subexprs); 4291 if (IS_ERR(hist_field)) { 4292 ret = PTR_ERR(hist_field); 4293 goto out; 4294 } 4295 4296 if (field_has_hist_vars(hist_field, 0)) { 4297 hist_err(tr, HIST_ERR_INVALID_REF_KEY, errpos(field_str)); 4298 destroy_hist_field(hist_field, 0); 4299 ret = -EINVAL; 4300 goto out; 4301 } 4302 4303 key_size = hist_field->size; 4304 } 4305 4306 hist_data->fields[key_idx] = hist_field; 4307 4308 key_size = ALIGN(key_size, sizeof(u64)); 4309 hist_data->fields[key_idx]->size = key_size; 4310 hist_data->fields[key_idx]->offset = key_offset; 4311 4312 hist_data->key_size += key_size; 4313 4314 if (hist_data->key_size > HIST_KEY_SIZE_MAX) { 4315 ret = -EINVAL; 4316 goto out; 4317 } 4318 4319 hist_data->n_keys++; 4320 hist_data->n_fields++; 4321 4322 if (WARN_ON(hist_data->n_keys > TRACING_MAP_KEYS_MAX)) 4323 return -EINVAL; 4324 4325 ret = key_size; 4326 out: 4327 return ret; 4328 } 4329 4330 static int create_key_fields(struct hist_trigger_data *hist_data, 4331 struct trace_event_file *file) 4332 { 4333 unsigned int i, key_offset = 0, n_vals = hist_data->n_vals; 4334 char *fields_str, *field_str; 4335 int ret = -EINVAL; 4336 4337 fields_str = hist_data->attrs->keys_str; 4338 if (!fields_str) 4339 goto out; 4340 4341 for (i = n_vals; i < n_vals + TRACING_MAP_KEYS_MAX; i++) { 4342 field_str = strsep(&fields_str, ","); 4343 if (!field_str) 4344 break; 4345 ret = create_key_field(hist_data, i, key_offset, 4346 file, field_str); 4347 if (ret < 0) 4348 goto out; 4349 key_offset += ret; 4350 } 4351 if (fields_str) { 4352 ret = -EINVAL; 4353 goto out; 4354 } 4355 ret = 0; 4356 out: 4357 return ret; 4358 } 4359 4360 static int create_var_fields(struct hist_trigger_data *hist_data, 4361 struct trace_event_file *file) 4362 { 4363 unsigned int i, j = hist_data->n_vals; 4364 int ret = 0; 4365 4366 unsigned int n_vars = hist_data->attrs->var_defs.n_vars; 4367 4368 for (i = 0; i < n_vars; i++) { 4369 char *var_name = hist_data->attrs->var_defs.name[i]; 4370 char *expr = hist_data->attrs->var_defs.expr[i]; 4371 4372 ret = create_var_field(hist_data, j++, file, var_name, expr); 4373 if (ret) 4374 goto out; 4375 } 4376 out: 4377 return ret; 4378 } 4379 4380 static void free_var_defs(struct hist_trigger_data *hist_data) 4381 { 4382 unsigned int i; 4383 4384 for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) { 4385 kfree(hist_data->attrs->var_defs.name[i]); 4386 kfree(hist_data->attrs->var_defs.expr[i]); 4387 } 4388 4389 hist_data->attrs->var_defs.n_vars = 0; 4390 } 4391 4392 static int parse_var_defs(struct hist_trigger_data *hist_data) 4393 { 4394 struct trace_array *tr = hist_data->event_file->tr; 4395 char *s, *str, *var_name, *field_str; 4396 unsigned int i, j, n_vars = 0; 4397 int ret = 0; 4398 4399 for (i = 0; i < hist_data->attrs->n_assignments; i++) { 4400 str = hist_data->attrs->assignment_str[i]; 4401 for (j = 0; j < TRACING_MAP_VARS_MAX; j++) { 4402 field_str = strsep(&str, ","); 4403 if (!field_str) 4404 break; 4405 4406 var_name = strsep(&field_str, "="); 4407 if (!var_name || !field_str) { 4408 hist_err(tr, HIST_ERR_MALFORMED_ASSIGNMENT, 4409 errpos(var_name)); 4410 ret = -EINVAL; 4411 goto free; 4412 } 4413 4414 if (n_vars == TRACING_MAP_VARS_MAX) { 4415 hist_err(tr, HIST_ERR_TOO_MANY_VARS, errpos(var_name)); 4416 ret = -EINVAL; 4417 goto free; 4418 } 4419 4420 s = kstrdup(var_name, GFP_KERNEL); 4421 if (!s) { 4422 ret = -ENOMEM; 4423 goto free; 4424 } 4425 hist_data->attrs->var_defs.name[n_vars] = s; 4426 4427 s = kstrdup(field_str, GFP_KERNEL); 4428 if (!s) { 4429 ret = -ENOMEM; 4430 goto free; 4431 } 4432 hist_data->attrs->var_defs.expr[n_vars++] = s; 4433 4434 hist_data->attrs->var_defs.n_vars = n_vars; 4435 } 4436 } 4437 4438 return ret; 4439 free: 4440 free_var_defs(hist_data); 4441 4442 return ret; 4443 } 4444 4445 static int create_hist_fields(struct hist_trigger_data *hist_data, 4446 struct trace_event_file *file) 4447 { 4448 int ret; 4449 4450 ret = parse_var_defs(hist_data); 4451 if (ret) 4452 goto out; 4453 4454 ret = create_val_fields(hist_data, file); 4455 if (ret) 4456 goto out; 4457 4458 ret = create_var_fields(hist_data, file); 4459 if (ret) 4460 goto out; 4461 4462 ret = create_key_fields(hist_data, file); 4463 if (ret) 4464 goto out; 4465 out: 4466 free_var_defs(hist_data); 4467 4468 return ret; 4469 } 4470 4471 static int is_descending(struct trace_array *tr, const char *str) 4472 { 4473 if (!str) 4474 return 0; 4475 4476 if (strcmp(str, "descending") == 0) 4477 return 1; 4478 4479 if (strcmp(str, "ascending") == 0) 4480 return 0; 4481 4482 hist_err(tr, HIST_ERR_INVALID_SORT_MODIFIER, errpos((char *)str)); 4483 4484 return -EINVAL; 4485 } 4486 4487 static int create_sort_keys(struct hist_trigger_data *hist_data) 4488 { 4489 struct trace_array *tr = hist_data->event_file->tr; 4490 char *fields_str = hist_data->attrs->sort_key_str; 4491 struct tracing_map_sort_key *sort_key; 4492 int descending, ret = 0; 4493 unsigned int i, j, k; 4494 4495 hist_data->n_sort_keys = 1; /* we always have at least one, hitcount */ 4496 4497 if (!fields_str) 4498 goto out; 4499 4500 for (i = 0; i < TRACING_MAP_SORT_KEYS_MAX; i++) { 4501 struct hist_field *hist_field; 4502 char *field_str, *field_name; 4503 const char *test_name; 4504 4505 sort_key = &hist_data->sort_keys[i]; 4506 4507 field_str = strsep(&fields_str, ","); 4508 if (!field_str) 4509 break; 4510 4511 if (!*field_str) { 4512 ret = -EINVAL; 4513 hist_err(tr, HIST_ERR_EMPTY_SORT_FIELD, errpos("sort=")); 4514 break; 4515 } 4516 4517 if ((i == TRACING_MAP_SORT_KEYS_MAX - 1) && fields_str) { 4518 hist_err(tr, HIST_ERR_TOO_MANY_SORT_FIELDS, errpos("sort=")); 4519 ret = -EINVAL; 4520 break; 4521 } 4522 4523 field_name = strsep(&field_str, "."); 4524 if (!field_name || !*field_name) { 4525 ret = -EINVAL; 4526 hist_err(tr, HIST_ERR_EMPTY_SORT_FIELD, errpos("sort=")); 4527 break; 4528 } 4529 4530 if (strcmp(field_name, "hitcount") == 0) { 4531 descending = is_descending(tr, field_str); 4532 if (descending < 0) { 4533 ret = descending; 4534 break; 4535 } 4536 sort_key->descending = descending; 4537 continue; 4538 } 4539 4540 for (j = 1, k = 1; j < hist_data->n_fields; j++) { 4541 unsigned int idx; 4542 4543 hist_field = hist_data->fields[j]; 4544 if (hist_field->flags & HIST_FIELD_FL_VAR) 4545 continue; 4546 4547 idx = k++; 4548 4549 test_name = hist_field_name(hist_field, 0); 4550 4551 if (strcmp(field_name, test_name) == 0) { 4552 sort_key->field_idx = idx; 4553 descending = is_descending(tr, field_str); 4554 if (descending < 0) { 4555 ret = descending; 4556 goto out; 4557 } 4558 sort_key->descending = descending; 4559 break; 4560 } 4561 } 4562 if (j == hist_data->n_fields) { 4563 ret = -EINVAL; 4564 hist_err(tr, HIST_ERR_INVALID_SORT_FIELD, errpos(field_name)); 4565 break; 4566 } 4567 } 4568 4569 hist_data->n_sort_keys = i; 4570 out: 4571 return ret; 4572 } 4573 4574 static void destroy_actions(struct hist_trigger_data *hist_data) 4575 { 4576 unsigned int i; 4577 4578 for (i = 0; i < hist_data->n_actions; i++) { 4579 struct action_data *data = hist_data->actions[i]; 4580 4581 if (data->handler == HANDLER_ONMATCH) 4582 onmatch_destroy(data); 4583 else if (data->handler == HANDLER_ONMAX || 4584 data->handler == HANDLER_ONCHANGE) 4585 track_data_destroy(hist_data, data); 4586 else 4587 kfree(data); 4588 } 4589 } 4590 4591 static int parse_actions(struct hist_trigger_data *hist_data) 4592 { 4593 struct trace_array *tr = hist_data->event_file->tr; 4594 struct action_data *data; 4595 unsigned int i; 4596 int ret = 0; 4597 char *str; 4598 int len; 4599 4600 for (i = 0; i < hist_data->attrs->n_actions; i++) { 4601 str = hist_data->attrs->action_str[i]; 4602 4603 if ((len = str_has_prefix(str, "onmatch("))) { 4604 char *action_str = str + len; 4605 4606 data = onmatch_parse(tr, action_str); 4607 if (IS_ERR(data)) { 4608 ret = PTR_ERR(data); 4609 break; 4610 } 4611 } else if ((len = str_has_prefix(str, "onmax("))) { 4612 char *action_str = str + len; 4613 4614 data = track_data_parse(hist_data, action_str, 4615 HANDLER_ONMAX); 4616 if (IS_ERR(data)) { 4617 ret = PTR_ERR(data); 4618 break; 4619 } 4620 } else if ((len = str_has_prefix(str, "onchange("))) { 4621 char *action_str = str + len; 4622 4623 data = track_data_parse(hist_data, action_str, 4624 HANDLER_ONCHANGE); 4625 if (IS_ERR(data)) { 4626 ret = PTR_ERR(data); 4627 break; 4628 } 4629 } else { 4630 ret = -EINVAL; 4631 break; 4632 } 4633 4634 hist_data->actions[hist_data->n_actions++] = data; 4635 } 4636 4637 return ret; 4638 } 4639 4640 static int create_actions(struct hist_trigger_data *hist_data) 4641 { 4642 struct action_data *data; 4643 unsigned int i; 4644 int ret = 0; 4645 4646 for (i = 0; i < hist_data->attrs->n_actions; i++) { 4647 data = hist_data->actions[i]; 4648 4649 if (data->handler == HANDLER_ONMATCH) { 4650 ret = onmatch_create(hist_data, data); 4651 if (ret) 4652 break; 4653 } else if (data->handler == HANDLER_ONMAX || 4654 data->handler == HANDLER_ONCHANGE) { 4655 ret = track_data_create(hist_data, data); 4656 if (ret) 4657 break; 4658 } else { 4659 ret = -EINVAL; 4660 break; 4661 } 4662 } 4663 4664 return ret; 4665 } 4666 4667 static void print_actions(struct seq_file *m, 4668 struct hist_trigger_data *hist_data, 4669 struct tracing_map_elt *elt) 4670 { 4671 unsigned int i; 4672 4673 for (i = 0; i < hist_data->n_actions; i++) { 4674 struct action_data *data = hist_data->actions[i]; 4675 4676 if (data->action == ACTION_SNAPSHOT) 4677 continue; 4678 4679 if (data->handler == HANDLER_ONMAX || 4680 data->handler == HANDLER_ONCHANGE) 4681 track_data_print(m, hist_data, elt, data); 4682 } 4683 } 4684 4685 static void print_action_spec(struct seq_file *m, 4686 struct hist_trigger_data *hist_data, 4687 struct action_data *data) 4688 { 4689 unsigned int i; 4690 4691 if (data->action == ACTION_SAVE) { 4692 for (i = 0; i < hist_data->n_save_vars; i++) { 4693 seq_printf(m, "%s", hist_data->save_vars[i]->var->var.name); 4694 if (i < hist_data->n_save_vars - 1) 4695 seq_puts(m, ","); 4696 } 4697 } else if (data->action == ACTION_TRACE) { 4698 if (data->use_trace_keyword) 4699 seq_printf(m, "%s", data->synth_event_name); 4700 for (i = 0; i < data->n_params; i++) { 4701 if (i || data->use_trace_keyword) 4702 seq_puts(m, ","); 4703 seq_printf(m, "%s", data->params[i]); 4704 } 4705 } 4706 } 4707 4708 static void print_track_data_spec(struct seq_file *m, 4709 struct hist_trigger_data *hist_data, 4710 struct action_data *data) 4711 { 4712 if (data->handler == HANDLER_ONMAX) 4713 seq_puts(m, ":onmax("); 4714 else if (data->handler == HANDLER_ONCHANGE) 4715 seq_puts(m, ":onchange("); 4716 seq_printf(m, "%s", data->track_data.var_str); 4717 seq_printf(m, ").%s(", data->action_name); 4718 4719 print_action_spec(m, hist_data, data); 4720 4721 seq_puts(m, ")"); 4722 } 4723 4724 static void print_onmatch_spec(struct seq_file *m, 4725 struct hist_trigger_data *hist_data, 4726 struct action_data *data) 4727 { 4728 seq_printf(m, ":onmatch(%s.%s).", data->match_data.event_system, 4729 data->match_data.event); 4730 4731 seq_printf(m, "%s(", data->action_name); 4732 4733 print_action_spec(m, hist_data, data); 4734 4735 seq_puts(m, ")"); 4736 } 4737 4738 static bool actions_match(struct hist_trigger_data *hist_data, 4739 struct hist_trigger_data *hist_data_test) 4740 { 4741 unsigned int i, j; 4742 4743 if (hist_data->n_actions != hist_data_test->n_actions) 4744 return false; 4745 4746 for (i = 0; i < hist_data->n_actions; i++) { 4747 struct action_data *data = hist_data->actions[i]; 4748 struct action_data *data_test = hist_data_test->actions[i]; 4749 char *action_name, *action_name_test; 4750 4751 if (data->handler != data_test->handler) 4752 return false; 4753 if (data->action != data_test->action) 4754 return false; 4755 4756 if (data->n_params != data_test->n_params) 4757 return false; 4758 4759 for (j = 0; j < data->n_params; j++) { 4760 if (strcmp(data->params[j], data_test->params[j]) != 0) 4761 return false; 4762 } 4763 4764 if (data->use_trace_keyword) 4765 action_name = data->synth_event_name; 4766 else 4767 action_name = data->action_name; 4768 4769 if (data_test->use_trace_keyword) 4770 action_name_test = data_test->synth_event_name; 4771 else 4772 action_name_test = data_test->action_name; 4773 4774 if (strcmp(action_name, action_name_test) != 0) 4775 return false; 4776 4777 if (data->handler == HANDLER_ONMATCH) { 4778 if (strcmp(data->match_data.event_system, 4779 data_test->match_data.event_system) != 0) 4780 return false; 4781 if (strcmp(data->match_data.event, 4782 data_test->match_data.event) != 0) 4783 return false; 4784 } else if (data->handler == HANDLER_ONMAX || 4785 data->handler == HANDLER_ONCHANGE) { 4786 if (strcmp(data->track_data.var_str, 4787 data_test->track_data.var_str) != 0) 4788 return false; 4789 } 4790 } 4791 4792 return true; 4793 } 4794 4795 4796 static void print_actions_spec(struct seq_file *m, 4797 struct hist_trigger_data *hist_data) 4798 { 4799 unsigned int i; 4800 4801 for (i = 0; i < hist_data->n_actions; i++) { 4802 struct action_data *data = hist_data->actions[i]; 4803 4804 if (data->handler == HANDLER_ONMATCH) 4805 print_onmatch_spec(m, hist_data, data); 4806 else if (data->handler == HANDLER_ONMAX || 4807 data->handler == HANDLER_ONCHANGE) 4808 print_track_data_spec(m, hist_data, data); 4809 } 4810 } 4811 4812 static void destroy_field_var_hists(struct hist_trigger_data *hist_data) 4813 { 4814 unsigned int i; 4815 4816 for (i = 0; i < hist_data->n_field_var_hists; i++) { 4817 kfree(hist_data->field_var_hists[i]->cmd); 4818 kfree(hist_data->field_var_hists[i]); 4819 } 4820 } 4821 4822 static void destroy_hist_data(struct hist_trigger_data *hist_data) 4823 { 4824 if (!hist_data) 4825 return; 4826 4827 destroy_hist_trigger_attrs(hist_data->attrs); 4828 destroy_hist_fields(hist_data); 4829 tracing_map_destroy(hist_data->map); 4830 4831 destroy_actions(hist_data); 4832 destroy_field_vars(hist_data); 4833 destroy_field_var_hists(hist_data); 4834 4835 kfree(hist_data); 4836 } 4837 4838 static int create_tracing_map_fields(struct hist_trigger_data *hist_data) 4839 { 4840 struct tracing_map *map = hist_data->map; 4841 struct ftrace_event_field *field; 4842 struct hist_field *hist_field; 4843 int i, idx = 0; 4844 4845 for_each_hist_field(i, hist_data) { 4846 hist_field = hist_data->fields[i]; 4847 if (hist_field->flags & HIST_FIELD_FL_KEY) { 4848 tracing_map_cmp_fn_t cmp_fn; 4849 4850 field = hist_field->field; 4851 4852 if (hist_field->flags & HIST_FIELD_FL_STACKTRACE) 4853 cmp_fn = tracing_map_cmp_none; 4854 else if (!field || hist_field->flags & HIST_FIELD_FL_CPU) 4855 cmp_fn = tracing_map_cmp_num(hist_field->size, 4856 hist_field->is_signed); 4857 else if (is_string_field(field)) 4858 cmp_fn = tracing_map_cmp_string; 4859 else 4860 cmp_fn = tracing_map_cmp_num(field->size, 4861 field->is_signed); 4862 idx = tracing_map_add_key_field(map, 4863 hist_field->offset, 4864 cmp_fn); 4865 } else if (!(hist_field->flags & HIST_FIELD_FL_VAR)) 4866 idx = tracing_map_add_sum_field(map); 4867 4868 if (idx < 0) 4869 return idx; 4870 4871 if (hist_field->flags & HIST_FIELD_FL_VAR) { 4872 idx = tracing_map_add_var(map); 4873 if (idx < 0) 4874 return idx; 4875 hist_field->var.idx = idx; 4876 hist_field->var.hist_data = hist_data; 4877 } 4878 } 4879 4880 return 0; 4881 } 4882 4883 static struct hist_trigger_data * 4884 create_hist_data(unsigned int map_bits, 4885 struct hist_trigger_attrs *attrs, 4886 struct trace_event_file *file, 4887 bool remove) 4888 { 4889 const struct tracing_map_ops *map_ops = NULL; 4890 struct hist_trigger_data *hist_data; 4891 int ret = 0; 4892 4893 hist_data = kzalloc(sizeof(*hist_data), GFP_KERNEL); 4894 if (!hist_data) 4895 return ERR_PTR(-ENOMEM); 4896 4897 hist_data->attrs = attrs; 4898 hist_data->remove = remove; 4899 hist_data->event_file = file; 4900 4901 ret = parse_actions(hist_data); 4902 if (ret) 4903 goto free; 4904 4905 ret = create_hist_fields(hist_data, file); 4906 if (ret) 4907 goto free; 4908 4909 ret = create_sort_keys(hist_data); 4910 if (ret) 4911 goto free; 4912 4913 map_ops = &hist_trigger_elt_data_ops; 4914 4915 hist_data->map = tracing_map_create(map_bits, hist_data->key_size, 4916 map_ops, hist_data); 4917 if (IS_ERR(hist_data->map)) { 4918 ret = PTR_ERR(hist_data->map); 4919 hist_data->map = NULL; 4920 goto free; 4921 } 4922 4923 ret = create_tracing_map_fields(hist_data); 4924 if (ret) 4925 goto free; 4926 out: 4927 return hist_data; 4928 free: 4929 hist_data->attrs = NULL; 4930 4931 destroy_hist_data(hist_data); 4932 4933 hist_data = ERR_PTR(ret); 4934 4935 goto out; 4936 } 4937 4938 static void hist_trigger_elt_update(struct hist_trigger_data *hist_data, 4939 struct tracing_map_elt *elt, 4940 struct trace_buffer *buffer, void *rec, 4941 struct ring_buffer_event *rbe, 4942 u64 *var_ref_vals) 4943 { 4944 struct hist_elt_data *elt_data; 4945 struct hist_field *hist_field; 4946 unsigned int i, var_idx; 4947 u64 hist_val; 4948 4949 elt_data = elt->private_data; 4950 elt_data->var_ref_vals = var_ref_vals; 4951 4952 for_each_hist_val_field(i, hist_data) { 4953 hist_field = hist_data->fields[i]; 4954 hist_val = hist_field->fn(hist_field, elt, buffer, rbe, rec); 4955 if (hist_field->flags & HIST_FIELD_FL_VAR) { 4956 var_idx = hist_field->var.idx; 4957 4958 if (hist_field->flags & HIST_FIELD_FL_STRING) { 4959 unsigned int str_start, var_str_idx, idx; 4960 char *str, *val_str; 4961 unsigned int size; 4962 4963 str_start = hist_data->n_field_var_str + 4964 hist_data->n_save_var_str; 4965 var_str_idx = hist_field->var_str_idx; 4966 idx = str_start + var_str_idx; 4967 4968 str = elt_data->field_var_str[idx]; 4969 val_str = (char *)(uintptr_t)hist_val; 4970 4971 size = min(hist_field->size, STR_VAR_LEN_MAX); 4972 strscpy(str, val_str, size); 4973 4974 hist_val = (u64)(uintptr_t)str; 4975 } 4976 tracing_map_set_var(elt, var_idx, hist_val); 4977 continue; 4978 } 4979 tracing_map_update_sum(elt, i, hist_val); 4980 } 4981 4982 for_each_hist_key_field(i, hist_data) { 4983 hist_field = hist_data->fields[i]; 4984 if (hist_field->flags & HIST_FIELD_FL_VAR) { 4985 hist_val = hist_field->fn(hist_field, elt, buffer, rbe, rec); 4986 var_idx = hist_field->var.idx; 4987 tracing_map_set_var(elt, var_idx, hist_val); 4988 } 4989 } 4990 4991 update_field_vars(hist_data, elt, buffer, rbe, rec); 4992 } 4993 4994 static inline void add_to_key(char *compound_key, void *key, 4995 struct hist_field *key_field, void *rec) 4996 { 4997 size_t size = key_field->size; 4998 4999 if (key_field->flags & HIST_FIELD_FL_STRING) { 5000 struct ftrace_event_field *field; 5001 5002 field = key_field->field; 5003 if (field->filter_type == FILTER_DYN_STRING || 5004 field->filter_type == FILTER_RDYN_STRING) 5005 size = *(u32 *)(rec + field->offset) >> 16; 5006 else if (field->filter_type == FILTER_STATIC_STRING) 5007 size = field->size; 5008 5009 /* ensure NULL-termination */ 5010 if (size > key_field->size - 1) 5011 size = key_field->size - 1; 5012 5013 strncpy(compound_key + key_field->offset, (char *)key, size); 5014 } else 5015 memcpy(compound_key + key_field->offset, key, size); 5016 } 5017 5018 static void 5019 hist_trigger_actions(struct hist_trigger_data *hist_data, 5020 struct tracing_map_elt *elt, 5021 struct trace_buffer *buffer, void *rec, 5022 struct ring_buffer_event *rbe, void *key, 5023 u64 *var_ref_vals) 5024 { 5025 struct action_data *data; 5026 unsigned int i; 5027 5028 for (i = 0; i < hist_data->n_actions; i++) { 5029 data = hist_data->actions[i]; 5030 data->fn(hist_data, elt, buffer, rec, rbe, key, data, var_ref_vals); 5031 } 5032 } 5033 5034 static void event_hist_trigger(struct event_trigger_data *data, 5035 struct trace_buffer *buffer, void *rec, 5036 struct ring_buffer_event *rbe) 5037 { 5038 struct hist_trigger_data *hist_data = data->private_data; 5039 bool use_compound_key = (hist_data->n_keys > 1); 5040 unsigned long entries[HIST_STACKTRACE_DEPTH]; 5041 u64 var_ref_vals[TRACING_MAP_VARS_MAX]; 5042 char compound_key[HIST_KEY_SIZE_MAX]; 5043 struct tracing_map_elt *elt = NULL; 5044 struct hist_field *key_field; 5045 u64 field_contents; 5046 void *key = NULL; 5047 unsigned int i; 5048 5049 memset(compound_key, 0, hist_data->key_size); 5050 5051 for_each_hist_key_field(i, hist_data) { 5052 key_field = hist_data->fields[i]; 5053 5054 if (key_field->flags & HIST_FIELD_FL_STACKTRACE) { 5055 memset(entries, 0, HIST_STACKTRACE_SIZE); 5056 stack_trace_save(entries, HIST_STACKTRACE_DEPTH, 5057 HIST_STACKTRACE_SKIP); 5058 key = entries; 5059 } else { 5060 field_contents = key_field->fn(key_field, elt, buffer, rbe, rec); 5061 if (key_field->flags & HIST_FIELD_FL_STRING) { 5062 key = (void *)(unsigned long)field_contents; 5063 use_compound_key = true; 5064 } else 5065 key = (void *)&field_contents; 5066 } 5067 5068 if (use_compound_key) 5069 add_to_key(compound_key, key, key_field, rec); 5070 } 5071 5072 if (use_compound_key) 5073 key = compound_key; 5074 5075 if (hist_data->n_var_refs && 5076 !resolve_var_refs(hist_data, key, var_ref_vals, false)) 5077 return; 5078 5079 elt = tracing_map_insert(hist_data->map, key); 5080 if (!elt) 5081 return; 5082 5083 hist_trigger_elt_update(hist_data, elt, buffer, rec, rbe, var_ref_vals); 5084 5085 if (resolve_var_refs(hist_data, key, var_ref_vals, true)) 5086 hist_trigger_actions(hist_data, elt, buffer, rec, rbe, key, var_ref_vals); 5087 } 5088 5089 static void hist_trigger_stacktrace_print(struct seq_file *m, 5090 unsigned long *stacktrace_entries, 5091 unsigned int max_entries) 5092 { 5093 unsigned int spaces = 8; 5094 unsigned int i; 5095 5096 for (i = 0; i < max_entries; i++) { 5097 if (!stacktrace_entries[i]) 5098 return; 5099 5100 seq_printf(m, "%*c", 1 + spaces, ' '); 5101 seq_printf(m, "%pS\n", (void*)stacktrace_entries[i]); 5102 } 5103 } 5104 5105 static void hist_trigger_print_key(struct seq_file *m, 5106 struct hist_trigger_data *hist_data, 5107 void *key, 5108 struct tracing_map_elt *elt) 5109 { 5110 struct hist_field *key_field; 5111 bool multiline = false; 5112 const char *field_name; 5113 unsigned int i; 5114 u64 uval; 5115 5116 seq_puts(m, "{ "); 5117 5118 for_each_hist_key_field(i, hist_data) { 5119 key_field = hist_data->fields[i]; 5120 5121 if (i > hist_data->n_vals) 5122 seq_puts(m, ", "); 5123 5124 field_name = hist_field_name(key_field, 0); 5125 5126 if (key_field->flags & HIST_FIELD_FL_HEX) { 5127 uval = *(u64 *)(key + key_field->offset); 5128 seq_printf(m, "%s: %llx", field_name, uval); 5129 } else if (key_field->flags & HIST_FIELD_FL_SYM) { 5130 uval = *(u64 *)(key + key_field->offset); 5131 seq_printf(m, "%s: [%llx] %-45ps", field_name, 5132 uval, (void *)(uintptr_t)uval); 5133 } else if (key_field->flags & HIST_FIELD_FL_SYM_OFFSET) { 5134 uval = *(u64 *)(key + key_field->offset); 5135 seq_printf(m, "%s: [%llx] %-55pS", field_name, 5136 uval, (void *)(uintptr_t)uval); 5137 } else if (key_field->flags & HIST_FIELD_FL_EXECNAME) { 5138 struct hist_elt_data *elt_data = elt->private_data; 5139 char *comm; 5140 5141 if (WARN_ON_ONCE(!elt_data)) 5142 return; 5143 5144 comm = elt_data->comm; 5145 5146 uval = *(u64 *)(key + key_field->offset); 5147 seq_printf(m, "%s: %-16s[%10llu]", field_name, 5148 comm, uval); 5149 } else if (key_field->flags & HIST_FIELD_FL_SYSCALL) { 5150 const char *syscall_name; 5151 5152 uval = *(u64 *)(key + key_field->offset); 5153 syscall_name = get_syscall_name(uval); 5154 if (!syscall_name) 5155 syscall_name = "unknown_syscall"; 5156 5157 seq_printf(m, "%s: %-30s[%3llu]", field_name, 5158 syscall_name, uval); 5159 } else if (key_field->flags & HIST_FIELD_FL_STACKTRACE) { 5160 seq_puts(m, "stacktrace:\n"); 5161 hist_trigger_stacktrace_print(m, 5162 key + key_field->offset, 5163 HIST_STACKTRACE_DEPTH); 5164 multiline = true; 5165 } else if (key_field->flags & HIST_FIELD_FL_LOG2) { 5166 seq_printf(m, "%s: ~ 2^%-2llu", field_name, 5167 *(u64 *)(key + key_field->offset)); 5168 } else if (key_field->flags & HIST_FIELD_FL_BUCKET) { 5169 unsigned long buckets = key_field->buckets; 5170 uval = *(u64 *)(key + key_field->offset); 5171 seq_printf(m, "%s: ~ %llu-%llu", field_name, 5172 uval, uval + buckets -1); 5173 } else if (key_field->flags & HIST_FIELD_FL_STRING) { 5174 seq_printf(m, "%s: %-50s", field_name, 5175 (char *)(key + key_field->offset)); 5176 } else { 5177 uval = *(u64 *)(key + key_field->offset); 5178 seq_printf(m, "%s: %10llu", field_name, uval); 5179 } 5180 } 5181 5182 if (!multiline) 5183 seq_puts(m, " "); 5184 5185 seq_puts(m, "}"); 5186 } 5187 5188 static void hist_trigger_entry_print(struct seq_file *m, 5189 struct hist_trigger_data *hist_data, 5190 void *key, 5191 struct tracing_map_elt *elt) 5192 { 5193 const char *field_name; 5194 unsigned int i; 5195 5196 hist_trigger_print_key(m, hist_data, key, elt); 5197 5198 seq_printf(m, " hitcount: %10llu", 5199 tracing_map_read_sum(elt, HITCOUNT_IDX)); 5200 5201 for (i = 1; i < hist_data->n_vals; i++) { 5202 field_name = hist_field_name(hist_data->fields[i], 0); 5203 5204 if (hist_data->fields[i]->flags & HIST_FIELD_FL_VAR || 5205 hist_data->fields[i]->flags & HIST_FIELD_FL_EXPR) 5206 continue; 5207 5208 if (hist_data->fields[i]->flags & HIST_FIELD_FL_HEX) { 5209 seq_printf(m, " %s: %10llx", field_name, 5210 tracing_map_read_sum(elt, i)); 5211 } else { 5212 seq_printf(m, " %s: %10llu", field_name, 5213 tracing_map_read_sum(elt, i)); 5214 } 5215 } 5216 5217 print_actions(m, hist_data, elt); 5218 5219 seq_puts(m, "\n"); 5220 } 5221 5222 static int print_entries(struct seq_file *m, 5223 struct hist_trigger_data *hist_data) 5224 { 5225 struct tracing_map_sort_entry **sort_entries = NULL; 5226 struct tracing_map *map = hist_data->map; 5227 int i, n_entries; 5228 5229 n_entries = tracing_map_sort_entries(map, hist_data->sort_keys, 5230 hist_data->n_sort_keys, 5231 &sort_entries); 5232 if (n_entries < 0) 5233 return n_entries; 5234 5235 for (i = 0; i < n_entries; i++) 5236 hist_trigger_entry_print(m, hist_data, 5237 sort_entries[i]->key, 5238 sort_entries[i]->elt); 5239 5240 tracing_map_destroy_sort_entries(sort_entries, n_entries); 5241 5242 return n_entries; 5243 } 5244 5245 static void hist_trigger_show(struct seq_file *m, 5246 struct event_trigger_data *data, int n) 5247 { 5248 struct hist_trigger_data *hist_data; 5249 int n_entries; 5250 5251 if (n > 0) 5252 seq_puts(m, "\n\n"); 5253 5254 seq_puts(m, "# event histogram\n#\n# trigger info: "); 5255 data->ops->print(m, data->ops, data); 5256 seq_puts(m, "#\n\n"); 5257 5258 hist_data = data->private_data; 5259 n_entries = print_entries(m, hist_data); 5260 if (n_entries < 0) 5261 n_entries = 0; 5262 5263 track_data_snapshot_print(m, hist_data); 5264 5265 seq_printf(m, "\nTotals:\n Hits: %llu\n Entries: %u\n Dropped: %llu\n", 5266 (u64)atomic64_read(&hist_data->map->hits), 5267 n_entries, (u64)atomic64_read(&hist_data->map->drops)); 5268 } 5269 5270 static int hist_show(struct seq_file *m, void *v) 5271 { 5272 struct event_trigger_data *data; 5273 struct trace_event_file *event_file; 5274 int n = 0, ret = 0; 5275 5276 mutex_lock(&event_mutex); 5277 5278 event_file = event_file_data(m->private); 5279 if (unlikely(!event_file)) { 5280 ret = -ENODEV; 5281 goto out_unlock; 5282 } 5283 5284 list_for_each_entry(data, &event_file->triggers, list) { 5285 if (data->cmd_ops->trigger_type == ETT_EVENT_HIST) 5286 hist_trigger_show(m, data, n++); 5287 } 5288 5289 out_unlock: 5290 mutex_unlock(&event_mutex); 5291 5292 return ret; 5293 } 5294 5295 static int event_hist_open(struct inode *inode, struct file *file) 5296 { 5297 int ret; 5298 5299 ret = security_locked_down(LOCKDOWN_TRACEFS); 5300 if (ret) 5301 return ret; 5302 5303 return single_open(file, hist_show, file); 5304 } 5305 5306 const struct file_operations event_hist_fops = { 5307 .open = event_hist_open, 5308 .read = seq_read, 5309 .llseek = seq_lseek, 5310 .release = single_release, 5311 }; 5312 5313 #ifdef CONFIG_HIST_TRIGGERS_DEBUG 5314 static void hist_field_debug_show_flags(struct seq_file *m, 5315 unsigned long flags) 5316 { 5317 seq_puts(m, " flags:\n"); 5318 5319 if (flags & HIST_FIELD_FL_KEY) 5320 seq_puts(m, " HIST_FIELD_FL_KEY\n"); 5321 else if (flags & HIST_FIELD_FL_HITCOUNT) 5322 seq_puts(m, " VAL: HIST_FIELD_FL_HITCOUNT\n"); 5323 else if (flags & HIST_FIELD_FL_VAR) 5324 seq_puts(m, " HIST_FIELD_FL_VAR\n"); 5325 else if (flags & HIST_FIELD_FL_VAR_REF) 5326 seq_puts(m, " HIST_FIELD_FL_VAR_REF\n"); 5327 else 5328 seq_puts(m, " VAL: normal u64 value\n"); 5329 5330 if (flags & HIST_FIELD_FL_ALIAS) 5331 seq_puts(m, " HIST_FIELD_FL_ALIAS\n"); 5332 else if (flags & HIST_FIELD_FL_CONST) 5333 seq_puts(m, " HIST_FIELD_FL_CONST\n"); 5334 } 5335 5336 static int hist_field_debug_show(struct seq_file *m, 5337 struct hist_field *field, unsigned long flags) 5338 { 5339 if ((field->flags & flags) != flags) { 5340 seq_printf(m, "ERROR: bad flags - %lx\n", flags); 5341 return -EINVAL; 5342 } 5343 5344 hist_field_debug_show_flags(m, field->flags); 5345 if (field->field) 5346 seq_printf(m, " ftrace_event_field name: %s\n", 5347 field->field->name); 5348 5349 if (field->flags & HIST_FIELD_FL_VAR) { 5350 seq_printf(m, " var.name: %s\n", field->var.name); 5351 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n", 5352 field->var.idx); 5353 } 5354 5355 if (field->flags & HIST_FIELD_FL_CONST) 5356 seq_printf(m, " constant: %llu\n", field->constant); 5357 5358 if (field->flags & HIST_FIELD_FL_ALIAS) 5359 seq_printf(m, " var_ref_idx (into hist_data->var_refs[]): %u\n", 5360 field->var_ref_idx); 5361 5362 if (field->flags & HIST_FIELD_FL_VAR_REF) { 5363 seq_printf(m, " name: %s\n", field->name); 5364 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n", 5365 field->var.idx); 5366 seq_printf(m, " var.hist_data: %p\n", field->var.hist_data); 5367 seq_printf(m, " var_ref_idx (into hist_data->var_refs[]): %u\n", 5368 field->var_ref_idx); 5369 if (field->system) 5370 seq_printf(m, " system: %s\n", field->system); 5371 if (field->event_name) 5372 seq_printf(m, " event_name: %s\n", field->event_name); 5373 } 5374 5375 seq_printf(m, " type: %s\n", field->type); 5376 seq_printf(m, " size: %u\n", field->size); 5377 seq_printf(m, " is_signed: %u\n", field->is_signed); 5378 5379 return 0; 5380 } 5381 5382 static int field_var_debug_show(struct seq_file *m, 5383 struct field_var *field_var, unsigned int i, 5384 bool save_vars) 5385 { 5386 const char *vars_name = save_vars ? "save_vars" : "field_vars"; 5387 struct hist_field *field; 5388 int ret = 0; 5389 5390 seq_printf(m, "\n hist_data->%s[%d]:\n", vars_name, i); 5391 5392 field = field_var->var; 5393 5394 seq_printf(m, "\n %s[%d].var:\n", vars_name, i); 5395 5396 hist_field_debug_show_flags(m, field->flags); 5397 seq_printf(m, " var.name: %s\n", field->var.name); 5398 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n", 5399 field->var.idx); 5400 5401 field = field_var->val; 5402 5403 seq_printf(m, "\n %s[%d].val:\n", vars_name, i); 5404 if (field->field) 5405 seq_printf(m, " ftrace_event_field name: %s\n", 5406 field->field->name); 5407 else { 5408 ret = -EINVAL; 5409 goto out; 5410 } 5411 5412 seq_printf(m, " type: %s\n", field->type); 5413 seq_printf(m, " size: %u\n", field->size); 5414 seq_printf(m, " is_signed: %u\n", field->is_signed); 5415 out: 5416 return ret; 5417 } 5418 5419 static int hist_action_debug_show(struct seq_file *m, 5420 struct action_data *data, int i) 5421 { 5422 int ret = 0; 5423 5424 if (data->handler == HANDLER_ONMAX || 5425 data->handler == HANDLER_ONCHANGE) { 5426 seq_printf(m, "\n hist_data->actions[%d].track_data.var_ref:\n", i); 5427 ret = hist_field_debug_show(m, data->track_data.var_ref, 5428 HIST_FIELD_FL_VAR_REF); 5429 if (ret) 5430 goto out; 5431 5432 seq_printf(m, "\n hist_data->actions[%d].track_data.track_var:\n", i); 5433 ret = hist_field_debug_show(m, data->track_data.track_var, 5434 HIST_FIELD_FL_VAR); 5435 if (ret) 5436 goto out; 5437 } 5438 5439 if (data->handler == HANDLER_ONMATCH) { 5440 seq_printf(m, "\n hist_data->actions[%d].match_data.event_system: %s\n", 5441 i, data->match_data.event_system); 5442 seq_printf(m, " hist_data->actions[%d].match_data.event: %s\n", 5443 i, data->match_data.event); 5444 } 5445 out: 5446 return ret; 5447 } 5448 5449 static int hist_actions_debug_show(struct seq_file *m, 5450 struct hist_trigger_data *hist_data) 5451 { 5452 int i, ret = 0; 5453 5454 if (hist_data->n_actions) 5455 seq_puts(m, "\n action tracking variables (for onmax()/onchange()/onmatch()):\n"); 5456 5457 for (i = 0; i < hist_data->n_actions; i++) { 5458 struct action_data *action = hist_data->actions[i]; 5459 5460 ret = hist_action_debug_show(m, action, i); 5461 if (ret) 5462 goto out; 5463 } 5464 5465 if (hist_data->n_save_vars) 5466 seq_puts(m, "\n save action variables (save() params):\n"); 5467 5468 for (i = 0; i < hist_data->n_save_vars; i++) { 5469 ret = field_var_debug_show(m, hist_data->save_vars[i], i, true); 5470 if (ret) 5471 goto out; 5472 } 5473 out: 5474 return ret; 5475 } 5476 5477 static void hist_trigger_debug_show(struct seq_file *m, 5478 struct event_trigger_data *data, int n) 5479 { 5480 struct hist_trigger_data *hist_data; 5481 int i, ret; 5482 5483 if (n > 0) 5484 seq_puts(m, "\n\n"); 5485 5486 seq_puts(m, "# event histogram\n#\n# trigger info: "); 5487 data->ops->print(m, data->ops, data); 5488 seq_puts(m, "#\n\n"); 5489 5490 hist_data = data->private_data; 5491 5492 seq_printf(m, "hist_data: %p\n\n", hist_data); 5493 seq_printf(m, " n_vals: %u\n", hist_data->n_vals); 5494 seq_printf(m, " n_keys: %u\n", hist_data->n_keys); 5495 seq_printf(m, " n_fields: %u\n", hist_data->n_fields); 5496 5497 seq_puts(m, "\n val fields:\n\n"); 5498 5499 seq_puts(m, " hist_data->fields[0]:\n"); 5500 ret = hist_field_debug_show(m, hist_data->fields[0], 5501 HIST_FIELD_FL_HITCOUNT); 5502 if (ret) 5503 return; 5504 5505 for (i = 1; i < hist_data->n_vals; i++) { 5506 seq_printf(m, "\n hist_data->fields[%d]:\n", i); 5507 ret = hist_field_debug_show(m, hist_data->fields[i], 0); 5508 if (ret) 5509 return; 5510 } 5511 5512 seq_puts(m, "\n key fields:\n"); 5513 5514 for (i = hist_data->n_vals; i < hist_data->n_fields; i++) { 5515 seq_printf(m, "\n hist_data->fields[%d]:\n", i); 5516 ret = hist_field_debug_show(m, hist_data->fields[i], 5517 HIST_FIELD_FL_KEY); 5518 if (ret) 5519 return; 5520 } 5521 5522 if (hist_data->n_var_refs) 5523 seq_puts(m, "\n variable reference fields:\n"); 5524 5525 for (i = 0; i < hist_data->n_var_refs; i++) { 5526 seq_printf(m, "\n hist_data->var_refs[%d]:\n", i); 5527 ret = hist_field_debug_show(m, hist_data->var_refs[i], 5528 HIST_FIELD_FL_VAR_REF); 5529 if (ret) 5530 return; 5531 } 5532 5533 if (hist_data->n_field_vars) 5534 seq_puts(m, "\n field variables:\n"); 5535 5536 for (i = 0; i < hist_data->n_field_vars; i++) { 5537 ret = field_var_debug_show(m, hist_data->field_vars[i], i, false); 5538 if (ret) 5539 return; 5540 } 5541 5542 ret = hist_actions_debug_show(m, hist_data); 5543 if (ret) 5544 return; 5545 } 5546 5547 static int hist_debug_show(struct seq_file *m, void *v) 5548 { 5549 struct event_trigger_data *data; 5550 struct trace_event_file *event_file; 5551 int n = 0, ret = 0; 5552 5553 mutex_lock(&event_mutex); 5554 5555 event_file = event_file_data(m->private); 5556 if (unlikely(!event_file)) { 5557 ret = -ENODEV; 5558 goto out_unlock; 5559 } 5560 5561 list_for_each_entry(data, &event_file->triggers, list) { 5562 if (data->cmd_ops->trigger_type == ETT_EVENT_HIST) 5563 hist_trigger_debug_show(m, data, n++); 5564 } 5565 5566 out_unlock: 5567 mutex_unlock(&event_mutex); 5568 5569 return ret; 5570 } 5571 5572 static int event_hist_debug_open(struct inode *inode, struct file *file) 5573 { 5574 int ret; 5575 5576 ret = security_locked_down(LOCKDOWN_TRACEFS); 5577 if (ret) 5578 return ret; 5579 5580 return single_open(file, hist_debug_show, file); 5581 } 5582 5583 const struct file_operations event_hist_debug_fops = { 5584 .open = event_hist_debug_open, 5585 .read = seq_read, 5586 .llseek = seq_lseek, 5587 .release = single_release, 5588 }; 5589 #endif 5590 5591 static void hist_field_print(struct seq_file *m, struct hist_field *hist_field) 5592 { 5593 const char *field_name = hist_field_name(hist_field, 0); 5594 5595 if (hist_field->var.name) 5596 seq_printf(m, "%s=", hist_field->var.name); 5597 5598 if (hist_field->flags & HIST_FIELD_FL_CPU) 5599 seq_puts(m, "common_cpu"); 5600 else if (hist_field->flags & HIST_FIELD_FL_CONST) 5601 seq_printf(m, "%llu", hist_field->constant); 5602 else if (field_name) { 5603 if (hist_field->flags & HIST_FIELD_FL_VAR_REF || 5604 hist_field->flags & HIST_FIELD_FL_ALIAS) 5605 seq_putc(m, '$'); 5606 seq_printf(m, "%s", field_name); 5607 } else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP) 5608 seq_puts(m, "common_timestamp"); 5609 5610 if (hist_field->flags) { 5611 if (!(hist_field->flags & HIST_FIELD_FL_VAR_REF) && 5612 !(hist_field->flags & HIST_FIELD_FL_EXPR)) { 5613 const char *flags = get_hist_field_flags(hist_field); 5614 5615 if (flags) 5616 seq_printf(m, ".%s", flags); 5617 } 5618 } 5619 if (hist_field->buckets) 5620 seq_printf(m, "=%ld", hist_field->buckets); 5621 } 5622 5623 static int event_hist_trigger_print(struct seq_file *m, 5624 struct event_trigger_ops *ops, 5625 struct event_trigger_data *data) 5626 { 5627 struct hist_trigger_data *hist_data = data->private_data; 5628 struct hist_field *field; 5629 bool have_var = false; 5630 unsigned int i; 5631 5632 seq_puts(m, HIST_PREFIX); 5633 5634 if (data->name) 5635 seq_printf(m, "%s:", data->name); 5636 5637 seq_puts(m, "keys="); 5638 5639 for_each_hist_key_field(i, hist_data) { 5640 field = hist_data->fields[i]; 5641 5642 if (i > hist_data->n_vals) 5643 seq_puts(m, ","); 5644 5645 if (field->flags & HIST_FIELD_FL_STACKTRACE) 5646 seq_puts(m, "stacktrace"); 5647 else 5648 hist_field_print(m, field); 5649 } 5650 5651 seq_puts(m, ":vals="); 5652 5653 for_each_hist_val_field(i, hist_data) { 5654 field = hist_data->fields[i]; 5655 if (field->flags & HIST_FIELD_FL_VAR) { 5656 have_var = true; 5657 continue; 5658 } 5659 5660 if (i == HITCOUNT_IDX) 5661 seq_puts(m, "hitcount"); 5662 else { 5663 seq_puts(m, ","); 5664 hist_field_print(m, field); 5665 } 5666 } 5667 5668 if (have_var) { 5669 unsigned int n = 0; 5670 5671 seq_puts(m, ":"); 5672 5673 for_each_hist_val_field(i, hist_data) { 5674 field = hist_data->fields[i]; 5675 5676 if (field->flags & HIST_FIELD_FL_VAR) { 5677 if (n++) 5678 seq_puts(m, ","); 5679 hist_field_print(m, field); 5680 } 5681 } 5682 } 5683 5684 seq_puts(m, ":sort="); 5685 5686 for (i = 0; i < hist_data->n_sort_keys; i++) { 5687 struct tracing_map_sort_key *sort_key; 5688 unsigned int idx, first_key_idx; 5689 5690 /* skip VAR vals */ 5691 first_key_idx = hist_data->n_vals - hist_data->n_vars; 5692 5693 sort_key = &hist_data->sort_keys[i]; 5694 idx = sort_key->field_idx; 5695 5696 if (WARN_ON(idx >= HIST_FIELDS_MAX)) 5697 return -EINVAL; 5698 5699 if (i > 0) 5700 seq_puts(m, ","); 5701 5702 if (idx == HITCOUNT_IDX) 5703 seq_puts(m, "hitcount"); 5704 else { 5705 if (idx >= first_key_idx) 5706 idx += hist_data->n_vars; 5707 hist_field_print(m, hist_data->fields[idx]); 5708 } 5709 5710 if (sort_key->descending) 5711 seq_puts(m, ".descending"); 5712 } 5713 seq_printf(m, ":size=%u", (1 << hist_data->map->map_bits)); 5714 if (hist_data->enable_timestamps) 5715 seq_printf(m, ":clock=%s", hist_data->attrs->clock); 5716 5717 print_actions_spec(m, hist_data); 5718 5719 if (data->filter_str) 5720 seq_printf(m, " if %s", data->filter_str); 5721 5722 if (data->paused) 5723 seq_puts(m, " [paused]"); 5724 else 5725 seq_puts(m, " [active]"); 5726 5727 seq_putc(m, '\n'); 5728 5729 return 0; 5730 } 5731 5732 static int event_hist_trigger_init(struct event_trigger_ops *ops, 5733 struct event_trigger_data *data) 5734 { 5735 struct hist_trigger_data *hist_data = data->private_data; 5736 5737 if (!data->ref && hist_data->attrs->name) 5738 save_named_trigger(hist_data->attrs->name, data); 5739 5740 data->ref++; 5741 5742 return 0; 5743 } 5744 5745 static void unregister_field_var_hists(struct hist_trigger_data *hist_data) 5746 { 5747 struct trace_event_file *file; 5748 unsigned int i; 5749 char *cmd; 5750 int ret; 5751 5752 for (i = 0; i < hist_data->n_field_var_hists; i++) { 5753 file = hist_data->field_var_hists[i]->hist_data->event_file; 5754 cmd = hist_data->field_var_hists[i]->cmd; 5755 ret = event_hist_trigger_parse(&trigger_hist_cmd, file, 5756 "!hist", "hist", cmd); 5757 WARN_ON_ONCE(ret < 0); 5758 } 5759 } 5760 5761 static void event_hist_trigger_free(struct event_trigger_ops *ops, 5762 struct event_trigger_data *data) 5763 { 5764 struct hist_trigger_data *hist_data = data->private_data; 5765 5766 if (WARN_ON_ONCE(data->ref <= 0)) 5767 return; 5768 5769 data->ref--; 5770 if (!data->ref) { 5771 if (data->name) 5772 del_named_trigger(data); 5773 5774 trigger_data_free(data); 5775 5776 remove_hist_vars(hist_data); 5777 5778 unregister_field_var_hists(hist_data); 5779 5780 destroy_hist_data(hist_data); 5781 } 5782 } 5783 5784 static struct event_trigger_ops event_hist_trigger_ops = { 5785 .trigger = event_hist_trigger, 5786 .print = event_hist_trigger_print, 5787 .init = event_hist_trigger_init, 5788 .free = event_hist_trigger_free, 5789 }; 5790 5791 static int event_hist_trigger_named_init(struct event_trigger_ops *ops, 5792 struct event_trigger_data *data) 5793 { 5794 data->ref++; 5795 5796 save_named_trigger(data->named_data->name, data); 5797 5798 event_hist_trigger_init(ops, data->named_data); 5799 5800 return 0; 5801 } 5802 5803 static void event_hist_trigger_named_free(struct event_trigger_ops *ops, 5804 struct event_trigger_data *data) 5805 { 5806 if (WARN_ON_ONCE(data->ref <= 0)) 5807 return; 5808 5809 event_hist_trigger_free(ops, data->named_data); 5810 5811 data->ref--; 5812 if (!data->ref) { 5813 del_named_trigger(data); 5814 trigger_data_free(data); 5815 } 5816 } 5817 5818 static struct event_trigger_ops event_hist_trigger_named_ops = { 5819 .trigger = event_hist_trigger, 5820 .print = event_hist_trigger_print, 5821 .init = event_hist_trigger_named_init, 5822 .free = event_hist_trigger_named_free, 5823 }; 5824 5825 static struct event_trigger_ops *event_hist_get_trigger_ops(char *cmd, 5826 char *param) 5827 { 5828 return &event_hist_trigger_ops; 5829 } 5830 5831 static void hist_clear(struct event_trigger_data *data) 5832 { 5833 struct hist_trigger_data *hist_data = data->private_data; 5834 5835 if (data->name) 5836 pause_named_trigger(data); 5837 5838 tracepoint_synchronize_unregister(); 5839 5840 tracing_map_clear(hist_data->map); 5841 5842 if (data->name) 5843 unpause_named_trigger(data); 5844 } 5845 5846 static bool compatible_field(struct ftrace_event_field *field, 5847 struct ftrace_event_field *test_field) 5848 { 5849 if (field == test_field) 5850 return true; 5851 if (field == NULL || test_field == NULL) 5852 return false; 5853 if (strcmp(field->name, test_field->name) != 0) 5854 return false; 5855 if (strcmp(field->type, test_field->type) != 0) 5856 return false; 5857 if (field->size != test_field->size) 5858 return false; 5859 if (field->is_signed != test_field->is_signed) 5860 return false; 5861 5862 return true; 5863 } 5864 5865 static bool hist_trigger_match(struct event_trigger_data *data, 5866 struct event_trigger_data *data_test, 5867 struct event_trigger_data *named_data, 5868 bool ignore_filter) 5869 { 5870 struct tracing_map_sort_key *sort_key, *sort_key_test; 5871 struct hist_trigger_data *hist_data, *hist_data_test; 5872 struct hist_field *key_field, *key_field_test; 5873 unsigned int i; 5874 5875 if (named_data && (named_data != data_test) && 5876 (named_data != data_test->named_data)) 5877 return false; 5878 5879 if (!named_data && is_named_trigger(data_test)) 5880 return false; 5881 5882 hist_data = data->private_data; 5883 hist_data_test = data_test->private_data; 5884 5885 if (hist_data->n_vals != hist_data_test->n_vals || 5886 hist_data->n_fields != hist_data_test->n_fields || 5887 hist_data->n_sort_keys != hist_data_test->n_sort_keys) 5888 return false; 5889 5890 if (!ignore_filter) { 5891 if ((data->filter_str && !data_test->filter_str) || 5892 (!data->filter_str && data_test->filter_str)) 5893 return false; 5894 } 5895 5896 for_each_hist_field(i, hist_data) { 5897 key_field = hist_data->fields[i]; 5898 key_field_test = hist_data_test->fields[i]; 5899 5900 if (key_field->flags != key_field_test->flags) 5901 return false; 5902 if (!compatible_field(key_field->field, key_field_test->field)) 5903 return false; 5904 if (key_field->offset != key_field_test->offset) 5905 return false; 5906 if (key_field->size != key_field_test->size) 5907 return false; 5908 if (key_field->is_signed != key_field_test->is_signed) 5909 return false; 5910 if (!!key_field->var.name != !!key_field_test->var.name) 5911 return false; 5912 if (key_field->var.name && 5913 strcmp(key_field->var.name, key_field_test->var.name) != 0) 5914 return false; 5915 } 5916 5917 for (i = 0; i < hist_data->n_sort_keys; i++) { 5918 sort_key = &hist_data->sort_keys[i]; 5919 sort_key_test = &hist_data_test->sort_keys[i]; 5920 5921 if (sort_key->field_idx != sort_key_test->field_idx || 5922 sort_key->descending != sort_key_test->descending) 5923 return false; 5924 } 5925 5926 if (!ignore_filter && data->filter_str && 5927 (strcmp(data->filter_str, data_test->filter_str) != 0)) 5928 return false; 5929 5930 if (!actions_match(hist_data, hist_data_test)) 5931 return false; 5932 5933 return true; 5934 } 5935 5936 static int hist_register_trigger(char *glob, 5937 struct event_trigger_data *data, 5938 struct trace_event_file *file) 5939 { 5940 struct hist_trigger_data *hist_data = data->private_data; 5941 struct event_trigger_data *test, *named_data = NULL; 5942 struct trace_array *tr = file->tr; 5943 int ret = 0; 5944 5945 if (hist_data->attrs->name) { 5946 named_data = find_named_trigger(hist_data->attrs->name); 5947 if (named_data) { 5948 if (!hist_trigger_match(data, named_data, named_data, 5949 true)) { 5950 hist_err(tr, HIST_ERR_NAMED_MISMATCH, errpos(hist_data->attrs->name)); 5951 ret = -EINVAL; 5952 goto out; 5953 } 5954 } 5955 } 5956 5957 if (hist_data->attrs->name && !named_data) 5958 goto new; 5959 5960 lockdep_assert_held(&event_mutex); 5961 5962 list_for_each_entry(test, &file->triggers, list) { 5963 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 5964 if (!hist_trigger_match(data, test, named_data, false)) 5965 continue; 5966 if (hist_data->attrs->pause) 5967 test->paused = true; 5968 else if (hist_data->attrs->cont) 5969 test->paused = false; 5970 else if (hist_data->attrs->clear) 5971 hist_clear(test); 5972 else { 5973 hist_err(tr, HIST_ERR_TRIGGER_EEXIST, 0); 5974 ret = -EEXIST; 5975 } 5976 goto out; 5977 } 5978 } 5979 new: 5980 if (hist_data->attrs->cont || hist_data->attrs->clear) { 5981 hist_err(tr, HIST_ERR_TRIGGER_ENOENT_CLEAR, 0); 5982 ret = -ENOENT; 5983 goto out; 5984 } 5985 5986 if (hist_data->attrs->pause) 5987 data->paused = true; 5988 5989 if (named_data) { 5990 data->private_data = named_data->private_data; 5991 set_named_trigger_data(data, named_data); 5992 data->ops = &event_hist_trigger_named_ops; 5993 } 5994 5995 if (data->ops->init) { 5996 ret = data->ops->init(data->ops, data); 5997 if (ret < 0) 5998 goto out; 5999 } 6000 6001 if (hist_data->enable_timestamps) { 6002 char *clock = hist_data->attrs->clock; 6003 6004 ret = tracing_set_clock(file->tr, hist_data->attrs->clock); 6005 if (ret) { 6006 hist_err(tr, HIST_ERR_SET_CLOCK_FAIL, errpos(clock)); 6007 goto out; 6008 } 6009 6010 tracing_set_filter_buffering(file->tr, true); 6011 } 6012 6013 if (named_data) 6014 destroy_hist_data(hist_data); 6015 6016 ret++; 6017 out: 6018 return ret; 6019 } 6020 6021 static int hist_trigger_enable(struct event_trigger_data *data, 6022 struct trace_event_file *file) 6023 { 6024 int ret = 0; 6025 6026 list_add_tail_rcu(&data->list, &file->triggers); 6027 6028 update_cond_flag(file); 6029 6030 if (trace_event_trigger_enable_disable(file, 1) < 0) { 6031 list_del_rcu(&data->list); 6032 update_cond_flag(file); 6033 ret--; 6034 } 6035 6036 return ret; 6037 } 6038 6039 static bool have_hist_trigger_match(struct event_trigger_data *data, 6040 struct trace_event_file *file) 6041 { 6042 struct hist_trigger_data *hist_data = data->private_data; 6043 struct event_trigger_data *test, *named_data = NULL; 6044 bool match = false; 6045 6046 lockdep_assert_held(&event_mutex); 6047 6048 if (hist_data->attrs->name) 6049 named_data = find_named_trigger(hist_data->attrs->name); 6050 6051 list_for_each_entry(test, &file->triggers, list) { 6052 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6053 if (hist_trigger_match(data, test, named_data, false)) { 6054 match = true; 6055 break; 6056 } 6057 } 6058 } 6059 6060 return match; 6061 } 6062 6063 static bool hist_trigger_check_refs(struct event_trigger_data *data, 6064 struct trace_event_file *file) 6065 { 6066 struct hist_trigger_data *hist_data = data->private_data; 6067 struct event_trigger_data *test, *named_data = NULL; 6068 6069 lockdep_assert_held(&event_mutex); 6070 6071 if (hist_data->attrs->name) 6072 named_data = find_named_trigger(hist_data->attrs->name); 6073 6074 list_for_each_entry(test, &file->triggers, list) { 6075 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6076 if (!hist_trigger_match(data, test, named_data, false)) 6077 continue; 6078 hist_data = test->private_data; 6079 if (check_var_refs(hist_data)) 6080 return true; 6081 break; 6082 } 6083 } 6084 6085 return false; 6086 } 6087 6088 static void hist_unregister_trigger(char *glob, 6089 struct event_trigger_data *data, 6090 struct trace_event_file *file) 6091 { 6092 struct hist_trigger_data *hist_data = data->private_data; 6093 struct event_trigger_data *test, *named_data = NULL; 6094 bool unregistered = false; 6095 6096 lockdep_assert_held(&event_mutex); 6097 6098 if (hist_data->attrs->name) 6099 named_data = find_named_trigger(hist_data->attrs->name); 6100 6101 list_for_each_entry(test, &file->triggers, list) { 6102 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6103 if (!hist_trigger_match(data, test, named_data, false)) 6104 continue; 6105 unregistered = true; 6106 list_del_rcu(&test->list); 6107 trace_event_trigger_enable_disable(file, 0); 6108 update_cond_flag(file); 6109 break; 6110 } 6111 } 6112 6113 if (unregistered && test->ops->free) 6114 test->ops->free(test->ops, test); 6115 6116 if (hist_data->enable_timestamps) { 6117 if (!hist_data->remove || unregistered) 6118 tracing_set_filter_buffering(file->tr, false); 6119 } 6120 } 6121 6122 static bool hist_file_check_refs(struct trace_event_file *file) 6123 { 6124 struct hist_trigger_data *hist_data; 6125 struct event_trigger_data *test; 6126 6127 lockdep_assert_held(&event_mutex); 6128 6129 list_for_each_entry(test, &file->triggers, list) { 6130 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6131 hist_data = test->private_data; 6132 if (check_var_refs(hist_data)) 6133 return true; 6134 } 6135 } 6136 6137 return false; 6138 } 6139 6140 static void hist_unreg_all(struct trace_event_file *file) 6141 { 6142 struct event_trigger_data *test, *n; 6143 struct hist_trigger_data *hist_data; 6144 struct synth_event *se; 6145 const char *se_name; 6146 6147 lockdep_assert_held(&event_mutex); 6148 6149 if (hist_file_check_refs(file)) 6150 return; 6151 6152 list_for_each_entry_safe(test, n, &file->triggers, list) { 6153 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6154 hist_data = test->private_data; 6155 list_del_rcu(&test->list); 6156 trace_event_trigger_enable_disable(file, 0); 6157 6158 se_name = trace_event_name(file->event_call); 6159 se = find_synth_event(se_name); 6160 if (se) 6161 se->ref--; 6162 6163 update_cond_flag(file); 6164 if (hist_data->enable_timestamps) 6165 tracing_set_filter_buffering(file->tr, false); 6166 if (test->ops->free) 6167 test->ops->free(test->ops, test); 6168 } 6169 } 6170 } 6171 6172 static int event_hist_trigger_parse(struct event_command *cmd_ops, 6173 struct trace_event_file *file, 6174 char *glob, char *cmd, char *param) 6175 { 6176 unsigned int hist_trigger_bits = TRACING_MAP_BITS_DEFAULT; 6177 struct event_trigger_data *trigger_data; 6178 struct hist_trigger_attrs *attrs; 6179 struct event_trigger_ops *trigger_ops; 6180 struct hist_trigger_data *hist_data; 6181 struct synth_event *se; 6182 const char *se_name; 6183 bool remove = false; 6184 char *trigger, *p, *start; 6185 int ret = 0; 6186 6187 lockdep_assert_held(&event_mutex); 6188 6189 WARN_ON(!glob); 6190 6191 if (strlen(glob)) { 6192 hist_err_clear(); 6193 last_cmd_set(file, param); 6194 } 6195 6196 if (!param) 6197 return -EINVAL; 6198 6199 if (glob[0] == '!') 6200 remove = true; 6201 6202 /* 6203 * separate the trigger from the filter (k:v [if filter]) 6204 * allowing for whitespace in the trigger 6205 */ 6206 p = trigger = param; 6207 do { 6208 p = strstr(p, "if"); 6209 if (!p) 6210 break; 6211 if (p == param) 6212 return -EINVAL; 6213 if (*(p - 1) != ' ' && *(p - 1) != '\t') { 6214 p++; 6215 continue; 6216 } 6217 if (p >= param + strlen(param) - (sizeof("if") - 1) - 1) 6218 return -EINVAL; 6219 if (*(p + sizeof("if") - 1) != ' ' && *(p + sizeof("if") - 1) != '\t') { 6220 p++; 6221 continue; 6222 } 6223 break; 6224 } while (1); 6225 6226 if (!p) 6227 param = NULL; 6228 else { 6229 *(p - 1) = '\0'; 6230 param = strstrip(p); 6231 trigger = strstrip(trigger); 6232 } 6233 6234 /* 6235 * To simplify arithmetic expression parsing, replace occurrences of 6236 * '.sym-offset' modifier with '.symXoffset' 6237 */ 6238 start = strstr(trigger, ".sym-offset"); 6239 while (start) { 6240 *(start + 4) = 'X'; 6241 start = strstr(start + 11, ".sym-offset"); 6242 } 6243 6244 attrs = parse_hist_trigger_attrs(file->tr, trigger); 6245 if (IS_ERR(attrs)) 6246 return PTR_ERR(attrs); 6247 6248 if (attrs->map_bits) 6249 hist_trigger_bits = attrs->map_bits; 6250 6251 hist_data = create_hist_data(hist_trigger_bits, attrs, file, remove); 6252 if (IS_ERR(hist_data)) { 6253 destroy_hist_trigger_attrs(attrs); 6254 return PTR_ERR(hist_data); 6255 } 6256 6257 trigger_ops = cmd_ops->get_trigger_ops(cmd, trigger); 6258 6259 trigger_data = kzalloc(sizeof(*trigger_data), GFP_KERNEL); 6260 if (!trigger_data) { 6261 ret = -ENOMEM; 6262 goto out_free; 6263 } 6264 6265 trigger_data->count = -1; 6266 trigger_data->ops = trigger_ops; 6267 trigger_data->cmd_ops = cmd_ops; 6268 6269 INIT_LIST_HEAD(&trigger_data->list); 6270 RCU_INIT_POINTER(trigger_data->filter, NULL); 6271 6272 trigger_data->private_data = hist_data; 6273 6274 /* if param is non-empty, it's supposed to be a filter */ 6275 if (param && cmd_ops->set_filter) { 6276 ret = cmd_ops->set_filter(param, trigger_data, file); 6277 if (ret < 0) 6278 goto out_free; 6279 } 6280 6281 if (remove) { 6282 if (!have_hist_trigger_match(trigger_data, file)) 6283 goto out_free; 6284 6285 if (hist_trigger_check_refs(trigger_data, file)) { 6286 ret = -EBUSY; 6287 goto out_free; 6288 } 6289 6290 cmd_ops->unreg(glob+1, trigger_data, file); 6291 se_name = trace_event_name(file->event_call); 6292 se = find_synth_event(se_name); 6293 if (se) 6294 se->ref--; 6295 ret = 0; 6296 goto out_free; 6297 } 6298 6299 ret = cmd_ops->reg(glob, trigger_data, file); 6300 /* 6301 * The above returns on success the # of triggers registered, 6302 * but if it didn't register any it returns zero. Consider no 6303 * triggers registered a failure too. 6304 */ 6305 if (!ret) { 6306 if (!(attrs->pause || attrs->cont || attrs->clear)) 6307 ret = -ENOENT; 6308 goto out_free; 6309 } else if (ret < 0) 6310 goto out_free; 6311 6312 if (get_named_trigger_data(trigger_data)) 6313 goto enable; 6314 6315 if (has_hist_vars(hist_data)) 6316 save_hist_vars(hist_data); 6317 6318 ret = create_actions(hist_data); 6319 if (ret) 6320 goto out_unreg; 6321 6322 ret = tracing_map_init(hist_data->map); 6323 if (ret) 6324 goto out_unreg; 6325 enable: 6326 ret = hist_trigger_enable(trigger_data, file); 6327 if (ret) 6328 goto out_unreg; 6329 6330 se_name = trace_event_name(file->event_call); 6331 se = find_synth_event(se_name); 6332 if (se) 6333 se->ref++; 6334 /* Just return zero, not the number of registered triggers */ 6335 ret = 0; 6336 out: 6337 if (ret == 0) 6338 hist_err_clear(); 6339 6340 return ret; 6341 out_unreg: 6342 cmd_ops->unreg(glob+1, trigger_data, file); 6343 out_free: 6344 if (cmd_ops->set_filter) 6345 cmd_ops->set_filter(NULL, trigger_data, NULL); 6346 6347 remove_hist_vars(hist_data); 6348 6349 kfree(trigger_data); 6350 6351 destroy_hist_data(hist_data); 6352 goto out; 6353 } 6354 6355 static struct event_command trigger_hist_cmd = { 6356 .name = "hist", 6357 .trigger_type = ETT_EVENT_HIST, 6358 .flags = EVENT_CMD_FL_NEEDS_REC, 6359 .parse = event_hist_trigger_parse, 6360 .reg = hist_register_trigger, 6361 .unreg = hist_unregister_trigger, 6362 .unreg_all = hist_unreg_all, 6363 .get_trigger_ops = event_hist_get_trigger_ops, 6364 .set_filter = set_trigger_filter, 6365 }; 6366 6367 __init int register_trigger_hist_cmd(void) 6368 { 6369 int ret; 6370 6371 ret = register_event_command(&trigger_hist_cmd); 6372 WARN_ON(ret < 0); 6373 6374 return ret; 6375 } 6376 6377 static void 6378 hist_enable_trigger(struct event_trigger_data *data, 6379 struct trace_buffer *buffer, void *rec, 6380 struct ring_buffer_event *event) 6381 { 6382 struct enable_trigger_data *enable_data = data->private_data; 6383 struct event_trigger_data *test; 6384 6385 list_for_each_entry_rcu(test, &enable_data->file->triggers, list, 6386 lockdep_is_held(&event_mutex)) { 6387 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6388 if (enable_data->enable) 6389 test->paused = false; 6390 else 6391 test->paused = true; 6392 } 6393 } 6394 } 6395 6396 static void 6397 hist_enable_count_trigger(struct event_trigger_data *data, 6398 struct trace_buffer *buffer, void *rec, 6399 struct ring_buffer_event *event) 6400 { 6401 if (!data->count) 6402 return; 6403 6404 if (data->count != -1) 6405 (data->count)--; 6406 6407 hist_enable_trigger(data, buffer, rec, event); 6408 } 6409 6410 static struct event_trigger_ops hist_enable_trigger_ops = { 6411 .trigger = hist_enable_trigger, 6412 .print = event_enable_trigger_print, 6413 .init = event_trigger_init, 6414 .free = event_enable_trigger_free, 6415 }; 6416 6417 static struct event_trigger_ops hist_enable_count_trigger_ops = { 6418 .trigger = hist_enable_count_trigger, 6419 .print = event_enable_trigger_print, 6420 .init = event_trigger_init, 6421 .free = event_enable_trigger_free, 6422 }; 6423 6424 static struct event_trigger_ops hist_disable_trigger_ops = { 6425 .trigger = hist_enable_trigger, 6426 .print = event_enable_trigger_print, 6427 .init = event_trigger_init, 6428 .free = event_enable_trigger_free, 6429 }; 6430 6431 static struct event_trigger_ops hist_disable_count_trigger_ops = { 6432 .trigger = hist_enable_count_trigger, 6433 .print = event_enable_trigger_print, 6434 .init = event_trigger_init, 6435 .free = event_enable_trigger_free, 6436 }; 6437 6438 static struct event_trigger_ops * 6439 hist_enable_get_trigger_ops(char *cmd, char *param) 6440 { 6441 struct event_trigger_ops *ops; 6442 bool enable; 6443 6444 enable = (strcmp(cmd, ENABLE_HIST_STR) == 0); 6445 6446 if (enable) 6447 ops = param ? &hist_enable_count_trigger_ops : 6448 &hist_enable_trigger_ops; 6449 else 6450 ops = param ? &hist_disable_count_trigger_ops : 6451 &hist_disable_trigger_ops; 6452 6453 return ops; 6454 } 6455 6456 static void hist_enable_unreg_all(struct trace_event_file *file) 6457 { 6458 struct event_trigger_data *test, *n; 6459 6460 list_for_each_entry_safe(test, n, &file->triggers, list) { 6461 if (test->cmd_ops->trigger_type == ETT_HIST_ENABLE) { 6462 list_del_rcu(&test->list); 6463 update_cond_flag(file); 6464 trace_event_trigger_enable_disable(file, 0); 6465 if (test->ops->free) 6466 test->ops->free(test->ops, test); 6467 } 6468 } 6469 } 6470 6471 static struct event_command trigger_hist_enable_cmd = { 6472 .name = ENABLE_HIST_STR, 6473 .trigger_type = ETT_HIST_ENABLE, 6474 .parse = event_enable_trigger_parse, 6475 .reg = event_enable_register_trigger, 6476 .unreg = event_enable_unregister_trigger, 6477 .unreg_all = hist_enable_unreg_all, 6478 .get_trigger_ops = hist_enable_get_trigger_ops, 6479 .set_filter = set_trigger_filter, 6480 }; 6481 6482 static struct event_command trigger_hist_disable_cmd = { 6483 .name = DISABLE_HIST_STR, 6484 .trigger_type = ETT_HIST_ENABLE, 6485 .parse = event_enable_trigger_parse, 6486 .reg = event_enable_register_trigger, 6487 .unreg = event_enable_unregister_trigger, 6488 .unreg_all = hist_enable_unreg_all, 6489 .get_trigger_ops = hist_enable_get_trigger_ops, 6490 .set_filter = set_trigger_filter, 6491 }; 6492 6493 static __init void unregister_trigger_hist_enable_disable_cmds(void) 6494 { 6495 unregister_event_command(&trigger_hist_enable_cmd); 6496 unregister_event_command(&trigger_hist_disable_cmd); 6497 } 6498 6499 __init int register_trigger_hist_enable_disable_cmds(void) 6500 { 6501 int ret; 6502 6503 ret = register_event_command(&trigger_hist_enable_cmd); 6504 if (WARN_ON(ret < 0)) 6505 return ret; 6506 ret = register_event_command(&trigger_hist_disable_cmd); 6507 if (WARN_ON(ret < 0)) 6508 unregister_trigger_hist_enable_disable_cmds(); 6509 6510 return ret; 6511 } 6512