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 C(NEED_NOHC_VAL, "Non-hitcount value is required for 'nohitcount'"), 74 75 #undef C 76 #define C(a, b) HIST_ERR_##a 77 78 enum { ERRORS }; 79 80 #undef C 81 #define C(a, b) b 82 83 static const char *err_text[] = { ERRORS }; 84 85 struct hist_field; 86 87 typedef u64 (*hist_field_fn_t) (struct hist_field *field, 88 struct tracing_map_elt *elt, 89 struct trace_buffer *buffer, 90 struct ring_buffer_event *rbe, 91 void *event); 92 93 #define HIST_FIELD_OPERANDS_MAX 2 94 #define HIST_FIELDS_MAX (TRACING_MAP_FIELDS_MAX + TRACING_MAP_VARS_MAX) 95 #define HIST_ACTIONS_MAX 8 96 #define HIST_CONST_DIGITS_MAX 21 97 #define HIST_DIV_SHIFT 20 /* For optimizing division by constants */ 98 99 enum field_op_id { 100 FIELD_OP_NONE, 101 FIELD_OP_PLUS, 102 FIELD_OP_MINUS, 103 FIELD_OP_UNARY_MINUS, 104 FIELD_OP_DIV, 105 FIELD_OP_MULT, 106 }; 107 108 enum hist_field_fn { 109 HIST_FIELD_FN_NOP, 110 HIST_FIELD_FN_VAR_REF, 111 HIST_FIELD_FN_COUNTER, 112 HIST_FIELD_FN_CONST, 113 HIST_FIELD_FN_LOG2, 114 HIST_FIELD_FN_BUCKET, 115 HIST_FIELD_FN_TIMESTAMP, 116 HIST_FIELD_FN_CPU, 117 HIST_FIELD_FN_STRING, 118 HIST_FIELD_FN_DYNSTRING, 119 HIST_FIELD_FN_RELDYNSTRING, 120 HIST_FIELD_FN_PSTRING, 121 HIST_FIELD_FN_S64, 122 HIST_FIELD_FN_U64, 123 HIST_FIELD_FN_S32, 124 HIST_FIELD_FN_U32, 125 HIST_FIELD_FN_S16, 126 HIST_FIELD_FN_U16, 127 HIST_FIELD_FN_S8, 128 HIST_FIELD_FN_U8, 129 HIST_FIELD_FN_UMINUS, 130 HIST_FIELD_FN_MINUS, 131 HIST_FIELD_FN_PLUS, 132 HIST_FIELD_FN_DIV, 133 HIST_FIELD_FN_MULT, 134 HIST_FIELD_FN_DIV_POWER2, 135 HIST_FIELD_FN_DIV_NOT_POWER2, 136 HIST_FIELD_FN_DIV_MULT_SHIFT, 137 HIST_FIELD_FN_EXECNAME, 138 HIST_FIELD_FN_STACK, 139 }; 140 141 /* 142 * A hist_var (histogram variable) contains variable information for 143 * hist_fields having the HIST_FIELD_FL_VAR or HIST_FIELD_FL_VAR_REF 144 * flag set. A hist_var has a variable name e.g. ts0, and is 145 * associated with a given histogram trigger, as specified by 146 * hist_data. The hist_var idx is the unique index assigned to the 147 * variable by the hist trigger's tracing_map. The idx is what is 148 * used to set a variable's value and, by a variable reference, to 149 * retrieve it. 150 */ 151 struct hist_var { 152 char *name; 153 struct hist_trigger_data *hist_data; 154 unsigned int idx; 155 }; 156 157 struct hist_field { 158 struct ftrace_event_field *field; 159 unsigned long flags; 160 unsigned long buckets; 161 const char *type; 162 struct hist_field *operands[HIST_FIELD_OPERANDS_MAX]; 163 struct hist_trigger_data *hist_data; 164 enum hist_field_fn fn_num; 165 unsigned int ref; 166 unsigned int size; 167 unsigned int offset; 168 unsigned int is_signed; 169 170 /* 171 * Variable fields contain variable-specific info in var. 172 */ 173 struct hist_var var; 174 enum field_op_id operator; 175 char *system; 176 char *event_name; 177 178 /* 179 * The name field is used for EXPR and VAR_REF fields. VAR 180 * fields contain the variable name in var.name. 181 */ 182 char *name; 183 184 /* 185 * When a histogram trigger is hit, if it has any references 186 * to variables, the values of those variables are collected 187 * into a var_ref_vals array by resolve_var_refs(). The 188 * current value of each variable is read from the tracing_map 189 * using the hist field's hist_var.idx and entered into the 190 * var_ref_idx entry i.e. var_ref_vals[var_ref_idx]. 191 */ 192 unsigned int var_ref_idx; 193 bool read_once; 194 195 unsigned int var_str_idx; 196 197 /* Numeric literals are represented as u64 */ 198 u64 constant; 199 /* Used to optimize division by constants */ 200 u64 div_multiplier; 201 }; 202 203 static u64 hist_fn_call(struct hist_field *hist_field, 204 struct tracing_map_elt *elt, 205 struct trace_buffer *buffer, 206 struct ring_buffer_event *rbe, 207 void *event); 208 209 static u64 hist_field_const(struct hist_field *field, 210 struct tracing_map_elt *elt, 211 struct trace_buffer *buffer, 212 struct ring_buffer_event *rbe, 213 void *event) 214 { 215 return field->constant; 216 } 217 218 static u64 hist_field_counter(struct hist_field *field, 219 struct tracing_map_elt *elt, 220 struct trace_buffer *buffer, 221 struct ring_buffer_event *rbe, 222 void *event) 223 { 224 return 1; 225 } 226 227 static u64 hist_field_string(struct hist_field *hist_field, 228 struct tracing_map_elt *elt, 229 struct trace_buffer *buffer, 230 struct ring_buffer_event *rbe, 231 void *event) 232 { 233 char *addr = (char *)(event + hist_field->field->offset); 234 235 return (u64)(unsigned long)addr; 236 } 237 238 static u64 hist_field_dynstring(struct hist_field *hist_field, 239 struct tracing_map_elt *elt, 240 struct trace_buffer *buffer, 241 struct ring_buffer_event *rbe, 242 void *event) 243 { 244 u32 str_item = *(u32 *)(event + hist_field->field->offset); 245 int str_loc = str_item & 0xffff; 246 char *addr = (char *)(event + str_loc); 247 248 return (u64)(unsigned long)addr; 249 } 250 251 static u64 hist_field_reldynstring(struct hist_field *hist_field, 252 struct tracing_map_elt *elt, 253 struct trace_buffer *buffer, 254 struct ring_buffer_event *rbe, 255 void *event) 256 { 257 u32 *item = event + hist_field->field->offset; 258 u32 str_item = *item; 259 int str_loc = str_item & 0xffff; 260 char *addr = (char *)&item[1] + str_loc; 261 262 return (u64)(unsigned long)addr; 263 } 264 265 static u64 hist_field_pstring(struct hist_field *hist_field, 266 struct tracing_map_elt *elt, 267 struct trace_buffer *buffer, 268 struct ring_buffer_event *rbe, 269 void *event) 270 { 271 char **addr = (char **)(event + hist_field->field->offset); 272 273 return (u64)(unsigned long)*addr; 274 } 275 276 static u64 hist_field_log2(struct hist_field *hist_field, 277 struct tracing_map_elt *elt, 278 struct trace_buffer *buffer, 279 struct ring_buffer_event *rbe, 280 void *event) 281 { 282 struct hist_field *operand = hist_field->operands[0]; 283 284 u64 val = hist_fn_call(operand, elt, buffer, rbe, event); 285 286 return (u64) ilog2(roundup_pow_of_two(val)); 287 } 288 289 static u64 hist_field_bucket(struct hist_field *hist_field, 290 struct tracing_map_elt *elt, 291 struct trace_buffer *buffer, 292 struct ring_buffer_event *rbe, 293 void *event) 294 { 295 struct hist_field *operand = hist_field->operands[0]; 296 unsigned long buckets = hist_field->buckets; 297 298 u64 val = hist_fn_call(operand, elt, buffer, rbe, event); 299 300 if (WARN_ON_ONCE(!buckets)) 301 return val; 302 303 if (val >= LONG_MAX) 304 val = div64_ul(val, buckets); 305 else 306 val = (u64)((unsigned long)val / buckets); 307 return val * buckets; 308 } 309 310 static u64 hist_field_plus(struct hist_field *hist_field, 311 struct tracing_map_elt *elt, 312 struct trace_buffer *buffer, 313 struct ring_buffer_event *rbe, 314 void *event) 315 { 316 struct hist_field *operand1 = hist_field->operands[0]; 317 struct hist_field *operand2 = hist_field->operands[1]; 318 319 u64 val1 = hist_fn_call(operand1, elt, buffer, rbe, event); 320 u64 val2 = hist_fn_call(operand2, elt, buffer, rbe, event); 321 322 return val1 + val2; 323 } 324 325 static u64 hist_field_minus(struct hist_field *hist_field, 326 struct tracing_map_elt *elt, 327 struct trace_buffer *buffer, 328 struct ring_buffer_event *rbe, 329 void *event) 330 { 331 struct hist_field *operand1 = hist_field->operands[0]; 332 struct hist_field *operand2 = hist_field->operands[1]; 333 334 u64 val1 = hist_fn_call(operand1, elt, buffer, rbe, event); 335 u64 val2 = hist_fn_call(operand2, elt, buffer, rbe, event); 336 337 return val1 - val2; 338 } 339 340 static u64 hist_field_div(struct hist_field *hist_field, 341 struct tracing_map_elt *elt, 342 struct trace_buffer *buffer, 343 struct ring_buffer_event *rbe, 344 void *event) 345 { 346 struct hist_field *operand1 = hist_field->operands[0]; 347 struct hist_field *operand2 = hist_field->operands[1]; 348 349 u64 val1 = hist_fn_call(operand1, elt, buffer, rbe, event); 350 u64 val2 = hist_fn_call(operand2, elt, buffer, rbe, event); 351 352 /* Return -1 for the undefined case */ 353 if (!val2) 354 return -1; 355 356 /* Use shift if the divisor is a power of 2 */ 357 if (!(val2 & (val2 - 1))) 358 return val1 >> __ffs64(val2); 359 360 return div64_u64(val1, val2); 361 } 362 363 static u64 div_by_power_of_two(struct hist_field *hist_field, 364 struct tracing_map_elt *elt, 365 struct trace_buffer *buffer, 366 struct ring_buffer_event *rbe, 367 void *event) 368 { 369 struct hist_field *operand1 = hist_field->operands[0]; 370 struct hist_field *operand2 = hist_field->operands[1]; 371 372 u64 val1 = hist_fn_call(operand1, elt, buffer, rbe, event); 373 374 return val1 >> __ffs64(operand2->constant); 375 } 376 377 static u64 div_by_not_power_of_two(struct hist_field *hist_field, 378 struct tracing_map_elt *elt, 379 struct trace_buffer *buffer, 380 struct ring_buffer_event *rbe, 381 void *event) 382 { 383 struct hist_field *operand1 = hist_field->operands[0]; 384 struct hist_field *operand2 = hist_field->operands[1]; 385 386 u64 val1 = hist_fn_call(operand1, elt, buffer, rbe, event); 387 388 return div64_u64(val1, operand2->constant); 389 } 390 391 static u64 div_by_mult_and_shift(struct hist_field *hist_field, 392 struct tracing_map_elt *elt, 393 struct trace_buffer *buffer, 394 struct ring_buffer_event *rbe, 395 void *event) 396 { 397 struct hist_field *operand1 = hist_field->operands[0]; 398 struct hist_field *operand2 = hist_field->operands[1]; 399 400 u64 val1 = hist_fn_call(operand1, elt, buffer, rbe, event); 401 402 /* 403 * If the divisor is a constant, do a multiplication and shift instead. 404 * 405 * Choose Z = some power of 2. If Y <= Z, then: 406 * X / Y = (X * (Z / Y)) / Z 407 * 408 * (Z / Y) is a constant (mult) which is calculated at parse time, so: 409 * X / Y = (X * mult) / Z 410 * 411 * The division by Z can be replaced by a shift since Z is a power of 2: 412 * X / Y = (X * mult) >> HIST_DIV_SHIFT 413 * 414 * As long, as X < Z the results will not be off by more than 1. 415 */ 416 if (val1 < (1 << HIST_DIV_SHIFT)) { 417 u64 mult = operand2->div_multiplier; 418 419 return (val1 * mult + ((1 << HIST_DIV_SHIFT) - 1)) >> HIST_DIV_SHIFT; 420 } 421 422 return div64_u64(val1, operand2->constant); 423 } 424 425 static u64 hist_field_mult(struct hist_field *hist_field, 426 struct tracing_map_elt *elt, 427 struct trace_buffer *buffer, 428 struct ring_buffer_event *rbe, 429 void *event) 430 { 431 struct hist_field *operand1 = hist_field->operands[0]; 432 struct hist_field *operand2 = hist_field->operands[1]; 433 434 u64 val1 = hist_fn_call(operand1, elt, buffer, rbe, event); 435 u64 val2 = hist_fn_call(operand2, elt, buffer, rbe, event); 436 437 return val1 * val2; 438 } 439 440 static u64 hist_field_unary_minus(struct hist_field *hist_field, 441 struct tracing_map_elt *elt, 442 struct trace_buffer *buffer, 443 struct ring_buffer_event *rbe, 444 void *event) 445 { 446 struct hist_field *operand = hist_field->operands[0]; 447 448 s64 sval = (s64)hist_fn_call(operand, elt, buffer, rbe, event); 449 u64 val = (u64)-sval; 450 451 return val; 452 } 453 454 #define DEFINE_HIST_FIELD_FN(type) \ 455 static u64 hist_field_##type(struct hist_field *hist_field, \ 456 struct tracing_map_elt *elt, \ 457 struct trace_buffer *buffer, \ 458 struct ring_buffer_event *rbe, \ 459 void *event) \ 460 { \ 461 type *addr = (type *)(event + hist_field->field->offset); \ 462 \ 463 return (u64)(unsigned long)*addr; \ 464 } 465 466 DEFINE_HIST_FIELD_FN(s64); 467 DEFINE_HIST_FIELD_FN(u64); 468 DEFINE_HIST_FIELD_FN(s32); 469 DEFINE_HIST_FIELD_FN(u32); 470 DEFINE_HIST_FIELD_FN(s16); 471 DEFINE_HIST_FIELD_FN(u16); 472 DEFINE_HIST_FIELD_FN(s8); 473 DEFINE_HIST_FIELD_FN(u8); 474 475 #define for_each_hist_field(i, hist_data) \ 476 for ((i) = 0; (i) < (hist_data)->n_fields; (i)++) 477 478 #define for_each_hist_val_field(i, hist_data) \ 479 for ((i) = 0; (i) < (hist_data)->n_vals; (i)++) 480 481 #define for_each_hist_key_field(i, hist_data) \ 482 for ((i) = (hist_data)->n_vals; (i) < (hist_data)->n_fields; (i)++) 483 484 #define HITCOUNT_IDX 0 485 #define HIST_KEY_SIZE_MAX (MAX_FILTER_STR_VAL + HIST_STACKTRACE_SIZE) 486 487 enum hist_field_flags { 488 HIST_FIELD_FL_HITCOUNT = 1 << 0, 489 HIST_FIELD_FL_KEY = 1 << 1, 490 HIST_FIELD_FL_STRING = 1 << 2, 491 HIST_FIELD_FL_HEX = 1 << 3, 492 HIST_FIELD_FL_SYM = 1 << 4, 493 HIST_FIELD_FL_SYM_OFFSET = 1 << 5, 494 HIST_FIELD_FL_EXECNAME = 1 << 6, 495 HIST_FIELD_FL_SYSCALL = 1 << 7, 496 HIST_FIELD_FL_STACKTRACE = 1 << 8, 497 HIST_FIELD_FL_LOG2 = 1 << 9, 498 HIST_FIELD_FL_TIMESTAMP = 1 << 10, 499 HIST_FIELD_FL_TIMESTAMP_USECS = 1 << 11, 500 HIST_FIELD_FL_VAR = 1 << 12, 501 HIST_FIELD_FL_EXPR = 1 << 13, 502 HIST_FIELD_FL_VAR_REF = 1 << 14, 503 HIST_FIELD_FL_CPU = 1 << 15, 504 HIST_FIELD_FL_ALIAS = 1 << 16, 505 HIST_FIELD_FL_BUCKET = 1 << 17, 506 HIST_FIELD_FL_CONST = 1 << 18, 507 HIST_FIELD_FL_PERCENT = 1 << 19, 508 HIST_FIELD_FL_GRAPH = 1 << 20, 509 }; 510 511 struct var_defs { 512 unsigned int n_vars; 513 char *name[TRACING_MAP_VARS_MAX]; 514 char *expr[TRACING_MAP_VARS_MAX]; 515 }; 516 517 struct hist_trigger_attrs { 518 char *keys_str; 519 char *vals_str; 520 char *sort_key_str; 521 char *name; 522 char *clock; 523 bool pause; 524 bool cont; 525 bool clear; 526 bool ts_in_usecs; 527 bool no_hitcount; 528 unsigned int map_bits; 529 530 char *assignment_str[TRACING_MAP_VARS_MAX]; 531 unsigned int n_assignments; 532 533 char *action_str[HIST_ACTIONS_MAX]; 534 unsigned int n_actions; 535 536 struct var_defs var_defs; 537 }; 538 539 struct field_var { 540 struct hist_field *var; 541 struct hist_field *val; 542 }; 543 544 struct field_var_hist { 545 struct hist_trigger_data *hist_data; 546 char *cmd; 547 }; 548 549 struct hist_trigger_data { 550 struct hist_field *fields[HIST_FIELDS_MAX]; 551 unsigned int n_vals; 552 unsigned int n_keys; 553 unsigned int n_fields; 554 unsigned int n_vars; 555 unsigned int n_var_str; 556 unsigned int key_size; 557 struct tracing_map_sort_key sort_keys[TRACING_MAP_SORT_KEYS_MAX]; 558 unsigned int n_sort_keys; 559 struct trace_event_file *event_file; 560 struct hist_trigger_attrs *attrs; 561 struct tracing_map *map; 562 bool enable_timestamps; 563 bool remove; 564 struct hist_field *var_refs[TRACING_MAP_VARS_MAX]; 565 unsigned int n_var_refs; 566 567 struct action_data *actions[HIST_ACTIONS_MAX]; 568 unsigned int n_actions; 569 570 struct field_var *field_vars[SYNTH_FIELDS_MAX]; 571 unsigned int n_field_vars; 572 unsigned int n_field_var_str; 573 struct field_var_hist *field_var_hists[SYNTH_FIELDS_MAX]; 574 unsigned int n_field_var_hists; 575 576 struct field_var *save_vars[SYNTH_FIELDS_MAX]; 577 unsigned int n_save_vars; 578 unsigned int n_save_var_str; 579 }; 580 581 struct action_data; 582 583 typedef void (*action_fn_t) (struct hist_trigger_data *hist_data, 584 struct tracing_map_elt *elt, 585 struct trace_buffer *buffer, void *rec, 586 struct ring_buffer_event *rbe, void *key, 587 struct action_data *data, u64 *var_ref_vals); 588 589 typedef bool (*check_track_val_fn_t) (u64 track_val, u64 var_val); 590 591 enum handler_id { 592 HANDLER_ONMATCH = 1, 593 HANDLER_ONMAX, 594 HANDLER_ONCHANGE, 595 }; 596 597 enum action_id { 598 ACTION_SAVE = 1, 599 ACTION_TRACE, 600 ACTION_SNAPSHOT, 601 }; 602 603 struct action_data { 604 enum handler_id handler; 605 enum action_id action; 606 char *action_name; 607 action_fn_t fn; 608 609 unsigned int n_params; 610 char *params[SYNTH_FIELDS_MAX]; 611 612 /* 613 * When a histogram trigger is hit, the values of any 614 * references to variables, including variables being passed 615 * as parameters to synthetic events, are collected into a 616 * var_ref_vals array. This var_ref_idx array is an array of 617 * indices into the var_ref_vals array, one for each synthetic 618 * event param, and is passed to the synthetic event 619 * invocation. 620 */ 621 unsigned int var_ref_idx[SYNTH_FIELDS_MAX]; 622 struct synth_event *synth_event; 623 bool use_trace_keyword; 624 char *synth_event_name; 625 626 union { 627 struct { 628 char *event; 629 char *event_system; 630 } match_data; 631 632 struct { 633 /* 634 * var_str contains the $-unstripped variable 635 * name referenced by var_ref, and used when 636 * printing the action. Because var_ref 637 * creation is deferred to create_actions(), 638 * we need a per-action way to save it until 639 * then, thus var_str. 640 */ 641 char *var_str; 642 643 /* 644 * var_ref refers to the variable being 645 * tracked e.g onmax($var). 646 */ 647 struct hist_field *var_ref; 648 649 /* 650 * track_var contains the 'invisible' tracking 651 * variable created to keep the current 652 * e.g. max value. 653 */ 654 struct hist_field *track_var; 655 656 check_track_val_fn_t check_val; 657 action_fn_t save_data; 658 } track_data; 659 }; 660 }; 661 662 struct track_data { 663 u64 track_val; 664 bool updated; 665 666 unsigned int key_len; 667 void *key; 668 struct tracing_map_elt elt; 669 670 struct action_data *action_data; 671 struct hist_trigger_data *hist_data; 672 }; 673 674 struct hist_elt_data { 675 char *comm; 676 u64 *var_ref_vals; 677 char **field_var_str; 678 int n_field_var_str; 679 }; 680 681 struct snapshot_context { 682 struct tracing_map_elt *elt; 683 void *key; 684 }; 685 686 /* 687 * Returns the specific division function to use if the divisor 688 * is constant. This avoids extra branches when the trigger is hit. 689 */ 690 static enum hist_field_fn hist_field_get_div_fn(struct hist_field *divisor) 691 { 692 u64 div = divisor->constant; 693 694 if (!(div & (div - 1))) 695 return HIST_FIELD_FN_DIV_POWER2; 696 697 /* If the divisor is too large, do a regular division */ 698 if (div > (1 << HIST_DIV_SHIFT)) 699 return HIST_FIELD_FN_DIV_NOT_POWER2; 700 701 divisor->div_multiplier = div64_u64((u64)(1 << HIST_DIV_SHIFT), div); 702 return HIST_FIELD_FN_DIV_MULT_SHIFT; 703 } 704 705 static void track_data_free(struct track_data *track_data) 706 { 707 struct hist_elt_data *elt_data; 708 709 if (!track_data) 710 return; 711 712 kfree(track_data->key); 713 714 elt_data = track_data->elt.private_data; 715 if (elt_data) { 716 kfree(elt_data->comm); 717 kfree(elt_data); 718 } 719 720 kfree(track_data); 721 } 722 723 static struct track_data *track_data_alloc(unsigned int key_len, 724 struct action_data *action_data, 725 struct hist_trigger_data *hist_data) 726 { 727 struct track_data *data = kzalloc(sizeof(*data), GFP_KERNEL); 728 struct hist_elt_data *elt_data; 729 730 if (!data) 731 return ERR_PTR(-ENOMEM); 732 733 data->key = kzalloc(key_len, GFP_KERNEL); 734 if (!data->key) { 735 track_data_free(data); 736 return ERR_PTR(-ENOMEM); 737 } 738 739 data->key_len = key_len; 740 data->action_data = action_data; 741 data->hist_data = hist_data; 742 743 elt_data = kzalloc(sizeof(*elt_data), GFP_KERNEL); 744 if (!elt_data) { 745 track_data_free(data); 746 return ERR_PTR(-ENOMEM); 747 } 748 749 data->elt.private_data = elt_data; 750 751 elt_data->comm = kzalloc(TASK_COMM_LEN, GFP_KERNEL); 752 if (!elt_data->comm) { 753 track_data_free(data); 754 return ERR_PTR(-ENOMEM); 755 } 756 757 return data; 758 } 759 760 #define HIST_PREFIX "hist:" 761 762 static char *last_cmd; 763 static char last_cmd_loc[MAX_FILTER_STR_VAL]; 764 765 static int errpos(char *str) 766 { 767 if (!str || !last_cmd) 768 return 0; 769 770 return err_pos(last_cmd, str); 771 } 772 773 static void last_cmd_set(struct trace_event_file *file, char *str) 774 { 775 const char *system = NULL, *name = NULL; 776 struct trace_event_call *call; 777 int len; 778 779 if (!str) 780 return; 781 782 /* sizeof() contains the nul byte */ 783 len = sizeof(HIST_PREFIX) + strlen(str); 784 kfree(last_cmd); 785 last_cmd = kzalloc(len, GFP_KERNEL); 786 if (!last_cmd) 787 return; 788 789 strcpy(last_cmd, HIST_PREFIX); 790 /* Again, sizeof() contains the nul byte */ 791 len -= sizeof(HIST_PREFIX); 792 strncat(last_cmd, str, len); 793 794 if (file) { 795 call = file->event_call; 796 system = call->class->system; 797 if (system) { 798 name = trace_event_name(call); 799 if (!name) 800 system = NULL; 801 } 802 } 803 804 if (system) 805 snprintf(last_cmd_loc, MAX_FILTER_STR_VAL, HIST_PREFIX "%s:%s", system, name); 806 } 807 808 static void hist_err(struct trace_array *tr, u8 err_type, u16 err_pos) 809 { 810 if (!last_cmd) 811 return; 812 813 tracing_log_err(tr, last_cmd_loc, last_cmd, err_text, 814 err_type, err_pos); 815 } 816 817 static void hist_err_clear(void) 818 { 819 if (last_cmd) 820 last_cmd[0] = '\0'; 821 last_cmd_loc[0] = '\0'; 822 } 823 824 typedef void (*synth_probe_func_t) (void *__data, u64 *var_ref_vals, 825 unsigned int *var_ref_idx); 826 827 static inline void trace_synth(struct synth_event *event, u64 *var_ref_vals, 828 unsigned int *var_ref_idx) 829 { 830 struct tracepoint *tp = event->tp; 831 832 if (unlikely(atomic_read(&tp->key.enabled) > 0)) { 833 struct tracepoint_func *probe_func_ptr; 834 synth_probe_func_t probe_func; 835 void *__data; 836 837 if (!(cpu_online(raw_smp_processor_id()))) 838 return; 839 840 probe_func_ptr = rcu_dereference_sched((tp)->funcs); 841 if (probe_func_ptr) { 842 do { 843 probe_func = probe_func_ptr->func; 844 __data = probe_func_ptr->data; 845 probe_func(__data, var_ref_vals, var_ref_idx); 846 } while ((++probe_func_ptr)->func); 847 } 848 } 849 } 850 851 static void action_trace(struct hist_trigger_data *hist_data, 852 struct tracing_map_elt *elt, 853 struct trace_buffer *buffer, void *rec, 854 struct ring_buffer_event *rbe, void *key, 855 struct action_data *data, u64 *var_ref_vals) 856 { 857 struct synth_event *event = data->synth_event; 858 859 trace_synth(event, var_ref_vals, data->var_ref_idx); 860 } 861 862 struct hist_var_data { 863 struct list_head list; 864 struct hist_trigger_data *hist_data; 865 }; 866 867 static u64 hist_field_timestamp(struct hist_field *hist_field, 868 struct tracing_map_elt *elt, 869 struct trace_buffer *buffer, 870 struct ring_buffer_event *rbe, 871 void *event) 872 { 873 struct hist_trigger_data *hist_data = hist_field->hist_data; 874 struct trace_array *tr = hist_data->event_file->tr; 875 876 u64 ts = ring_buffer_event_time_stamp(buffer, rbe); 877 878 if (hist_data->attrs->ts_in_usecs && trace_clock_in_ns(tr)) 879 ts = ns2usecs(ts); 880 881 return ts; 882 } 883 884 static u64 hist_field_cpu(struct hist_field *hist_field, 885 struct tracing_map_elt *elt, 886 struct trace_buffer *buffer, 887 struct ring_buffer_event *rbe, 888 void *event) 889 { 890 int cpu = smp_processor_id(); 891 892 return cpu; 893 } 894 895 /** 896 * check_field_for_var_ref - Check if a VAR_REF field references a variable 897 * @hist_field: The VAR_REF field to check 898 * @var_data: The hist trigger that owns the variable 899 * @var_idx: The trigger variable identifier 900 * 901 * Check the given VAR_REF field to see whether or not it references 902 * the given variable associated with the given trigger. 903 * 904 * Return: The VAR_REF field if it does reference the variable, NULL if not 905 */ 906 static struct hist_field * 907 check_field_for_var_ref(struct hist_field *hist_field, 908 struct hist_trigger_data *var_data, 909 unsigned int var_idx) 910 { 911 WARN_ON(!(hist_field && hist_field->flags & HIST_FIELD_FL_VAR_REF)); 912 913 if (hist_field && hist_field->var.idx == var_idx && 914 hist_field->var.hist_data == var_data) 915 return hist_field; 916 917 return NULL; 918 } 919 920 /** 921 * find_var_ref - Check if a trigger has a reference to a trigger variable 922 * @hist_data: The hist trigger that might have a reference to the variable 923 * @var_data: The hist trigger that owns the variable 924 * @var_idx: The trigger variable identifier 925 * 926 * Check the list of var_refs[] on the first hist trigger to see 927 * whether any of them are references to the variable on the second 928 * trigger. 929 * 930 * Return: The VAR_REF field referencing the variable if so, NULL if not 931 */ 932 static struct hist_field *find_var_ref(struct hist_trigger_data *hist_data, 933 struct hist_trigger_data *var_data, 934 unsigned int var_idx) 935 { 936 struct hist_field *hist_field; 937 unsigned int i; 938 939 for (i = 0; i < hist_data->n_var_refs; i++) { 940 hist_field = hist_data->var_refs[i]; 941 if (check_field_for_var_ref(hist_field, var_data, var_idx)) 942 return hist_field; 943 } 944 945 return NULL; 946 } 947 948 /** 949 * find_any_var_ref - Check if there is a reference to a given trigger variable 950 * @hist_data: The hist trigger 951 * @var_idx: The trigger variable identifier 952 * 953 * Check to see whether the given variable is currently referenced by 954 * any other trigger. 955 * 956 * The trigger the variable is defined on is explicitly excluded - the 957 * assumption being that a self-reference doesn't prevent a trigger 958 * from being removed. 959 * 960 * Return: The VAR_REF field referencing the variable if so, NULL if not 961 */ 962 static struct hist_field *find_any_var_ref(struct hist_trigger_data *hist_data, 963 unsigned int var_idx) 964 { 965 struct trace_array *tr = hist_data->event_file->tr; 966 struct hist_field *found = NULL; 967 struct hist_var_data *var_data; 968 969 list_for_each_entry(var_data, &tr->hist_vars, list) { 970 if (var_data->hist_data == hist_data) 971 continue; 972 found = find_var_ref(var_data->hist_data, hist_data, var_idx); 973 if (found) 974 break; 975 } 976 977 return found; 978 } 979 980 /** 981 * check_var_refs - Check if there is a reference to any of trigger's variables 982 * @hist_data: The hist trigger 983 * 984 * A trigger can define one or more variables. If any one of them is 985 * currently referenced by any other trigger, this function will 986 * determine that. 987 * 988 * Typically used to determine whether or not a trigger can be removed 989 * - if there are any references to a trigger's variables, it cannot. 990 * 991 * Return: True if there is a reference to any of trigger's variables 992 */ 993 static bool check_var_refs(struct hist_trigger_data *hist_data) 994 { 995 struct hist_field *field; 996 bool found = false; 997 int i; 998 999 for_each_hist_field(i, hist_data) { 1000 field = hist_data->fields[i]; 1001 if (field && field->flags & HIST_FIELD_FL_VAR) { 1002 if (find_any_var_ref(hist_data, field->var.idx)) { 1003 found = true; 1004 break; 1005 } 1006 } 1007 } 1008 1009 return found; 1010 } 1011 1012 static struct hist_var_data *find_hist_vars(struct hist_trigger_data *hist_data) 1013 { 1014 struct trace_array *tr = hist_data->event_file->tr; 1015 struct hist_var_data *var_data, *found = NULL; 1016 1017 list_for_each_entry(var_data, &tr->hist_vars, list) { 1018 if (var_data->hist_data == hist_data) { 1019 found = var_data; 1020 break; 1021 } 1022 } 1023 1024 return found; 1025 } 1026 1027 static bool field_has_hist_vars(struct hist_field *hist_field, 1028 unsigned int level) 1029 { 1030 int i; 1031 1032 if (level > 3) 1033 return false; 1034 1035 if (!hist_field) 1036 return false; 1037 1038 if (hist_field->flags & HIST_FIELD_FL_VAR || 1039 hist_field->flags & HIST_FIELD_FL_VAR_REF) 1040 return true; 1041 1042 for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++) { 1043 struct hist_field *operand; 1044 1045 operand = hist_field->operands[i]; 1046 if (field_has_hist_vars(operand, level + 1)) 1047 return true; 1048 } 1049 1050 return false; 1051 } 1052 1053 static bool has_hist_vars(struct hist_trigger_data *hist_data) 1054 { 1055 struct hist_field *hist_field; 1056 int i; 1057 1058 for_each_hist_field(i, hist_data) { 1059 hist_field = hist_data->fields[i]; 1060 if (field_has_hist_vars(hist_field, 0)) 1061 return true; 1062 } 1063 1064 return false; 1065 } 1066 1067 static int save_hist_vars(struct hist_trigger_data *hist_data) 1068 { 1069 struct trace_array *tr = hist_data->event_file->tr; 1070 struct hist_var_data *var_data; 1071 1072 var_data = find_hist_vars(hist_data); 1073 if (var_data) 1074 return 0; 1075 1076 if (tracing_check_open_get_tr(tr)) 1077 return -ENODEV; 1078 1079 var_data = kzalloc(sizeof(*var_data), GFP_KERNEL); 1080 if (!var_data) { 1081 trace_array_put(tr); 1082 return -ENOMEM; 1083 } 1084 1085 var_data->hist_data = hist_data; 1086 list_add(&var_data->list, &tr->hist_vars); 1087 1088 return 0; 1089 } 1090 1091 static void remove_hist_vars(struct hist_trigger_data *hist_data) 1092 { 1093 struct trace_array *tr = hist_data->event_file->tr; 1094 struct hist_var_data *var_data; 1095 1096 var_data = find_hist_vars(hist_data); 1097 if (!var_data) 1098 return; 1099 1100 if (WARN_ON(check_var_refs(hist_data))) 1101 return; 1102 1103 list_del(&var_data->list); 1104 1105 kfree(var_data); 1106 1107 trace_array_put(tr); 1108 } 1109 1110 static struct hist_field *find_var_field(struct hist_trigger_data *hist_data, 1111 const char *var_name) 1112 { 1113 struct hist_field *hist_field, *found = NULL; 1114 int i; 1115 1116 for_each_hist_field(i, hist_data) { 1117 hist_field = hist_data->fields[i]; 1118 if (hist_field && hist_field->flags & HIST_FIELD_FL_VAR && 1119 strcmp(hist_field->var.name, var_name) == 0) { 1120 found = hist_field; 1121 break; 1122 } 1123 } 1124 1125 return found; 1126 } 1127 1128 static struct hist_field *find_var(struct hist_trigger_data *hist_data, 1129 struct trace_event_file *file, 1130 const char *var_name) 1131 { 1132 struct hist_trigger_data *test_data; 1133 struct event_trigger_data *test; 1134 struct hist_field *hist_field; 1135 1136 lockdep_assert_held(&event_mutex); 1137 1138 hist_field = find_var_field(hist_data, var_name); 1139 if (hist_field) 1140 return hist_field; 1141 1142 list_for_each_entry(test, &file->triggers, list) { 1143 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 1144 test_data = test->private_data; 1145 hist_field = find_var_field(test_data, var_name); 1146 if (hist_field) 1147 return hist_field; 1148 } 1149 } 1150 1151 return NULL; 1152 } 1153 1154 static struct trace_event_file *find_var_file(struct trace_array *tr, 1155 char *system, 1156 char *event_name, 1157 char *var_name) 1158 { 1159 struct hist_trigger_data *var_hist_data; 1160 struct hist_var_data *var_data; 1161 struct trace_event_file *file, *found = NULL; 1162 1163 if (system) 1164 return find_event_file(tr, system, event_name); 1165 1166 list_for_each_entry(var_data, &tr->hist_vars, list) { 1167 var_hist_data = var_data->hist_data; 1168 file = var_hist_data->event_file; 1169 if (file == found) 1170 continue; 1171 1172 if (find_var_field(var_hist_data, var_name)) { 1173 if (found) { 1174 hist_err(tr, HIST_ERR_VAR_NOT_UNIQUE, errpos(var_name)); 1175 return NULL; 1176 } 1177 1178 found = file; 1179 } 1180 } 1181 1182 return found; 1183 } 1184 1185 static struct hist_field *find_file_var(struct trace_event_file *file, 1186 const char *var_name) 1187 { 1188 struct hist_trigger_data *test_data; 1189 struct event_trigger_data *test; 1190 struct hist_field *hist_field; 1191 1192 lockdep_assert_held(&event_mutex); 1193 1194 list_for_each_entry(test, &file->triggers, list) { 1195 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 1196 test_data = test->private_data; 1197 hist_field = find_var_field(test_data, var_name); 1198 if (hist_field) 1199 return hist_field; 1200 } 1201 } 1202 1203 return NULL; 1204 } 1205 1206 static struct hist_field * 1207 find_match_var(struct hist_trigger_data *hist_data, char *var_name) 1208 { 1209 struct trace_array *tr = hist_data->event_file->tr; 1210 struct hist_field *hist_field, *found = NULL; 1211 struct trace_event_file *file; 1212 unsigned int i; 1213 1214 for (i = 0; i < hist_data->n_actions; i++) { 1215 struct action_data *data = hist_data->actions[i]; 1216 1217 if (data->handler == HANDLER_ONMATCH) { 1218 char *system = data->match_data.event_system; 1219 char *event_name = data->match_data.event; 1220 1221 file = find_var_file(tr, system, event_name, var_name); 1222 if (!file) 1223 continue; 1224 hist_field = find_file_var(file, var_name); 1225 if (hist_field) { 1226 if (found) { 1227 hist_err(tr, HIST_ERR_VAR_NOT_UNIQUE, 1228 errpos(var_name)); 1229 return ERR_PTR(-EINVAL); 1230 } 1231 1232 found = hist_field; 1233 } 1234 } 1235 } 1236 return found; 1237 } 1238 1239 static struct hist_field *find_event_var(struct hist_trigger_data *hist_data, 1240 char *system, 1241 char *event_name, 1242 char *var_name) 1243 { 1244 struct trace_array *tr = hist_data->event_file->tr; 1245 struct hist_field *hist_field = NULL; 1246 struct trace_event_file *file; 1247 1248 if (!system || !event_name) { 1249 hist_field = find_match_var(hist_data, var_name); 1250 if (IS_ERR(hist_field)) 1251 return NULL; 1252 if (hist_field) 1253 return hist_field; 1254 } 1255 1256 file = find_var_file(tr, system, event_name, var_name); 1257 if (!file) 1258 return NULL; 1259 1260 hist_field = find_file_var(file, var_name); 1261 1262 return hist_field; 1263 } 1264 1265 static u64 hist_field_var_ref(struct hist_field *hist_field, 1266 struct tracing_map_elt *elt, 1267 struct trace_buffer *buffer, 1268 struct ring_buffer_event *rbe, 1269 void *event) 1270 { 1271 struct hist_elt_data *elt_data; 1272 u64 var_val = 0; 1273 1274 if (WARN_ON_ONCE(!elt)) 1275 return var_val; 1276 1277 elt_data = elt->private_data; 1278 var_val = elt_data->var_ref_vals[hist_field->var_ref_idx]; 1279 1280 return var_val; 1281 } 1282 1283 static bool resolve_var_refs(struct hist_trigger_data *hist_data, void *key, 1284 u64 *var_ref_vals, bool self) 1285 { 1286 struct hist_trigger_data *var_data; 1287 struct tracing_map_elt *var_elt; 1288 struct hist_field *hist_field; 1289 unsigned int i, var_idx; 1290 bool resolved = true; 1291 u64 var_val = 0; 1292 1293 for (i = 0; i < hist_data->n_var_refs; i++) { 1294 hist_field = hist_data->var_refs[i]; 1295 var_idx = hist_field->var.idx; 1296 var_data = hist_field->var.hist_data; 1297 1298 if (var_data == NULL) { 1299 resolved = false; 1300 break; 1301 } 1302 1303 if ((self && var_data != hist_data) || 1304 (!self && var_data == hist_data)) 1305 continue; 1306 1307 var_elt = tracing_map_lookup(var_data->map, key); 1308 if (!var_elt) { 1309 resolved = false; 1310 break; 1311 } 1312 1313 if (!tracing_map_var_set(var_elt, var_idx)) { 1314 resolved = false; 1315 break; 1316 } 1317 1318 if (self || !hist_field->read_once) 1319 var_val = tracing_map_read_var(var_elt, var_idx); 1320 else 1321 var_val = tracing_map_read_var_once(var_elt, var_idx); 1322 1323 var_ref_vals[i] = var_val; 1324 } 1325 1326 return resolved; 1327 } 1328 1329 static const char *hist_field_name(struct hist_field *field, 1330 unsigned int level) 1331 { 1332 const char *field_name = ""; 1333 1334 if (WARN_ON_ONCE(!field)) 1335 return field_name; 1336 1337 if (level > 1) 1338 return field_name; 1339 1340 if (field->field) 1341 field_name = field->field->name; 1342 else if (field->flags & HIST_FIELD_FL_LOG2 || 1343 field->flags & HIST_FIELD_FL_ALIAS || 1344 field->flags & HIST_FIELD_FL_BUCKET) 1345 field_name = hist_field_name(field->operands[0], ++level); 1346 else if (field->flags & HIST_FIELD_FL_CPU) 1347 field_name = "common_cpu"; 1348 else if (field->flags & HIST_FIELD_FL_EXPR || 1349 field->flags & HIST_FIELD_FL_VAR_REF) { 1350 if (field->system) { 1351 static char full_name[MAX_FILTER_STR_VAL]; 1352 1353 strcat(full_name, field->system); 1354 strcat(full_name, "."); 1355 strcat(full_name, field->event_name); 1356 strcat(full_name, "."); 1357 strcat(full_name, field->name); 1358 field_name = full_name; 1359 } else 1360 field_name = field->name; 1361 } else if (field->flags & HIST_FIELD_FL_TIMESTAMP) 1362 field_name = "common_timestamp"; 1363 else if (field->flags & HIST_FIELD_FL_STACKTRACE) { 1364 if (field->field) 1365 field_name = field->field->name; 1366 else 1367 field_name = "stacktrace"; 1368 } else if (field->flags & HIST_FIELD_FL_HITCOUNT) 1369 field_name = "hitcount"; 1370 1371 if (field_name == NULL) 1372 field_name = ""; 1373 1374 return field_name; 1375 } 1376 1377 static enum hist_field_fn select_value_fn(int field_size, int field_is_signed) 1378 { 1379 switch (field_size) { 1380 case 8: 1381 if (field_is_signed) 1382 return HIST_FIELD_FN_S64; 1383 else 1384 return HIST_FIELD_FN_U64; 1385 case 4: 1386 if (field_is_signed) 1387 return HIST_FIELD_FN_S32; 1388 else 1389 return HIST_FIELD_FN_U32; 1390 case 2: 1391 if (field_is_signed) 1392 return HIST_FIELD_FN_S16; 1393 else 1394 return HIST_FIELD_FN_U16; 1395 case 1: 1396 if (field_is_signed) 1397 return HIST_FIELD_FN_S8; 1398 else 1399 return HIST_FIELD_FN_U8; 1400 } 1401 1402 return HIST_FIELD_FN_NOP; 1403 } 1404 1405 static int parse_map_size(char *str) 1406 { 1407 unsigned long size, map_bits; 1408 int ret; 1409 1410 ret = kstrtoul(str, 0, &size); 1411 if (ret) 1412 goto out; 1413 1414 map_bits = ilog2(roundup_pow_of_two(size)); 1415 if (map_bits < TRACING_MAP_BITS_MIN || 1416 map_bits > TRACING_MAP_BITS_MAX) 1417 ret = -EINVAL; 1418 else 1419 ret = map_bits; 1420 out: 1421 return ret; 1422 } 1423 1424 static void destroy_hist_trigger_attrs(struct hist_trigger_attrs *attrs) 1425 { 1426 unsigned int i; 1427 1428 if (!attrs) 1429 return; 1430 1431 for (i = 0; i < attrs->n_assignments; i++) 1432 kfree(attrs->assignment_str[i]); 1433 1434 for (i = 0; i < attrs->n_actions; i++) 1435 kfree(attrs->action_str[i]); 1436 1437 kfree(attrs->name); 1438 kfree(attrs->sort_key_str); 1439 kfree(attrs->keys_str); 1440 kfree(attrs->vals_str); 1441 kfree(attrs->clock); 1442 kfree(attrs); 1443 } 1444 1445 static int parse_action(char *str, struct hist_trigger_attrs *attrs) 1446 { 1447 int ret = -EINVAL; 1448 1449 if (attrs->n_actions >= HIST_ACTIONS_MAX) 1450 return ret; 1451 1452 if ((str_has_prefix(str, "onmatch(")) || 1453 (str_has_prefix(str, "onmax(")) || 1454 (str_has_prefix(str, "onchange("))) { 1455 attrs->action_str[attrs->n_actions] = kstrdup(str, GFP_KERNEL); 1456 if (!attrs->action_str[attrs->n_actions]) { 1457 ret = -ENOMEM; 1458 return ret; 1459 } 1460 attrs->n_actions++; 1461 ret = 0; 1462 } 1463 return ret; 1464 } 1465 1466 static int parse_assignment(struct trace_array *tr, 1467 char *str, struct hist_trigger_attrs *attrs) 1468 { 1469 int len, ret = 0; 1470 1471 if ((len = str_has_prefix(str, "key=")) || 1472 (len = str_has_prefix(str, "keys="))) { 1473 attrs->keys_str = kstrdup(str + len, GFP_KERNEL); 1474 if (!attrs->keys_str) { 1475 ret = -ENOMEM; 1476 goto out; 1477 } 1478 } else if ((len = str_has_prefix(str, "val=")) || 1479 (len = str_has_prefix(str, "vals=")) || 1480 (len = str_has_prefix(str, "values="))) { 1481 attrs->vals_str = kstrdup(str + len, GFP_KERNEL); 1482 if (!attrs->vals_str) { 1483 ret = -ENOMEM; 1484 goto out; 1485 } 1486 } else if ((len = str_has_prefix(str, "sort="))) { 1487 attrs->sort_key_str = kstrdup(str + len, GFP_KERNEL); 1488 if (!attrs->sort_key_str) { 1489 ret = -ENOMEM; 1490 goto out; 1491 } 1492 } else if (str_has_prefix(str, "name=")) { 1493 attrs->name = kstrdup(str, GFP_KERNEL); 1494 if (!attrs->name) { 1495 ret = -ENOMEM; 1496 goto out; 1497 } 1498 } else if ((len = str_has_prefix(str, "clock="))) { 1499 str += len; 1500 1501 str = strstrip(str); 1502 attrs->clock = kstrdup(str, GFP_KERNEL); 1503 if (!attrs->clock) { 1504 ret = -ENOMEM; 1505 goto out; 1506 } 1507 } else if ((len = str_has_prefix(str, "size="))) { 1508 int map_bits = parse_map_size(str + len); 1509 1510 if (map_bits < 0) { 1511 ret = map_bits; 1512 goto out; 1513 } 1514 attrs->map_bits = map_bits; 1515 } else { 1516 char *assignment; 1517 1518 if (attrs->n_assignments == TRACING_MAP_VARS_MAX) { 1519 hist_err(tr, HIST_ERR_TOO_MANY_VARS, errpos(str)); 1520 ret = -EINVAL; 1521 goto out; 1522 } 1523 1524 assignment = kstrdup(str, GFP_KERNEL); 1525 if (!assignment) { 1526 ret = -ENOMEM; 1527 goto out; 1528 } 1529 1530 attrs->assignment_str[attrs->n_assignments++] = assignment; 1531 } 1532 out: 1533 return ret; 1534 } 1535 1536 static struct hist_trigger_attrs * 1537 parse_hist_trigger_attrs(struct trace_array *tr, char *trigger_str) 1538 { 1539 struct hist_trigger_attrs *attrs; 1540 int ret = 0; 1541 1542 attrs = kzalloc(sizeof(*attrs), GFP_KERNEL); 1543 if (!attrs) 1544 return ERR_PTR(-ENOMEM); 1545 1546 while (trigger_str) { 1547 char *str = strsep(&trigger_str, ":"); 1548 char *rhs; 1549 1550 rhs = strchr(str, '='); 1551 if (rhs) { 1552 if (!strlen(++rhs)) { 1553 ret = -EINVAL; 1554 hist_err(tr, HIST_ERR_EMPTY_ASSIGNMENT, errpos(str)); 1555 goto free; 1556 } 1557 ret = parse_assignment(tr, str, attrs); 1558 if (ret) 1559 goto free; 1560 } else if (strcmp(str, "nohitcount") == 0 || 1561 strcmp(str, "NOHC") == 0) 1562 attrs->no_hitcount = true; 1563 else if (strcmp(str, "pause") == 0) 1564 attrs->pause = true; 1565 else if ((strcmp(str, "cont") == 0) || 1566 (strcmp(str, "continue") == 0)) 1567 attrs->cont = true; 1568 else if (strcmp(str, "clear") == 0) 1569 attrs->clear = true; 1570 else { 1571 ret = parse_action(str, attrs); 1572 if (ret) 1573 goto free; 1574 } 1575 } 1576 1577 if (!attrs->keys_str) { 1578 ret = -EINVAL; 1579 goto free; 1580 } 1581 1582 if (!attrs->clock) { 1583 attrs->clock = kstrdup("global", GFP_KERNEL); 1584 if (!attrs->clock) { 1585 ret = -ENOMEM; 1586 goto free; 1587 } 1588 } 1589 1590 return attrs; 1591 free: 1592 destroy_hist_trigger_attrs(attrs); 1593 1594 return ERR_PTR(ret); 1595 } 1596 1597 static inline void save_comm(char *comm, struct task_struct *task) 1598 { 1599 if (!task->pid) { 1600 strcpy(comm, "<idle>"); 1601 return; 1602 } 1603 1604 if (WARN_ON_ONCE(task->pid < 0)) { 1605 strcpy(comm, "<XXX>"); 1606 return; 1607 } 1608 1609 strncpy(comm, task->comm, TASK_COMM_LEN); 1610 } 1611 1612 static void hist_elt_data_free(struct hist_elt_data *elt_data) 1613 { 1614 unsigned int i; 1615 1616 for (i = 0; i < elt_data->n_field_var_str; i++) 1617 kfree(elt_data->field_var_str[i]); 1618 1619 kfree(elt_data->field_var_str); 1620 1621 kfree(elt_data->comm); 1622 kfree(elt_data); 1623 } 1624 1625 static void hist_trigger_elt_data_free(struct tracing_map_elt *elt) 1626 { 1627 struct hist_elt_data *elt_data = elt->private_data; 1628 1629 hist_elt_data_free(elt_data); 1630 } 1631 1632 static int hist_trigger_elt_data_alloc(struct tracing_map_elt *elt) 1633 { 1634 struct hist_trigger_data *hist_data = elt->map->private_data; 1635 unsigned int size = TASK_COMM_LEN; 1636 struct hist_elt_data *elt_data; 1637 struct hist_field *hist_field; 1638 unsigned int i, n_str; 1639 1640 elt_data = kzalloc(sizeof(*elt_data), GFP_KERNEL); 1641 if (!elt_data) 1642 return -ENOMEM; 1643 1644 for_each_hist_field(i, hist_data) { 1645 hist_field = hist_data->fields[i]; 1646 1647 if (hist_field->flags & HIST_FIELD_FL_EXECNAME) { 1648 elt_data->comm = kzalloc(size, GFP_KERNEL); 1649 if (!elt_data->comm) { 1650 kfree(elt_data); 1651 return -ENOMEM; 1652 } 1653 break; 1654 } 1655 } 1656 1657 n_str = hist_data->n_field_var_str + hist_data->n_save_var_str + 1658 hist_data->n_var_str; 1659 if (n_str > SYNTH_FIELDS_MAX) { 1660 hist_elt_data_free(elt_data); 1661 return -EINVAL; 1662 } 1663 1664 BUILD_BUG_ON(STR_VAR_LEN_MAX & (sizeof(u64) - 1)); 1665 1666 size = STR_VAR_LEN_MAX; 1667 1668 elt_data->field_var_str = kcalloc(n_str, sizeof(char *), GFP_KERNEL); 1669 if (!elt_data->field_var_str) { 1670 hist_elt_data_free(elt_data); 1671 return -EINVAL; 1672 } 1673 elt_data->n_field_var_str = n_str; 1674 1675 for (i = 0; i < n_str; i++) { 1676 elt_data->field_var_str[i] = kzalloc(size, GFP_KERNEL); 1677 if (!elt_data->field_var_str[i]) { 1678 hist_elt_data_free(elt_data); 1679 return -ENOMEM; 1680 } 1681 } 1682 1683 elt->private_data = elt_data; 1684 1685 return 0; 1686 } 1687 1688 static void hist_trigger_elt_data_init(struct tracing_map_elt *elt) 1689 { 1690 struct hist_elt_data *elt_data = elt->private_data; 1691 1692 if (elt_data->comm) 1693 save_comm(elt_data->comm, current); 1694 } 1695 1696 static const struct tracing_map_ops hist_trigger_elt_data_ops = { 1697 .elt_alloc = hist_trigger_elt_data_alloc, 1698 .elt_free = hist_trigger_elt_data_free, 1699 .elt_init = hist_trigger_elt_data_init, 1700 }; 1701 1702 static const char *get_hist_field_flags(struct hist_field *hist_field) 1703 { 1704 const char *flags_str = NULL; 1705 1706 if (hist_field->flags & HIST_FIELD_FL_HEX) 1707 flags_str = "hex"; 1708 else if (hist_field->flags & HIST_FIELD_FL_SYM) 1709 flags_str = "sym"; 1710 else if (hist_field->flags & HIST_FIELD_FL_SYM_OFFSET) 1711 flags_str = "sym-offset"; 1712 else if (hist_field->flags & HIST_FIELD_FL_EXECNAME) 1713 flags_str = "execname"; 1714 else if (hist_field->flags & HIST_FIELD_FL_SYSCALL) 1715 flags_str = "syscall"; 1716 else if (hist_field->flags & HIST_FIELD_FL_LOG2) 1717 flags_str = "log2"; 1718 else if (hist_field->flags & HIST_FIELD_FL_BUCKET) 1719 flags_str = "buckets"; 1720 else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP_USECS) 1721 flags_str = "usecs"; 1722 else if (hist_field->flags & HIST_FIELD_FL_PERCENT) 1723 flags_str = "percent"; 1724 else if (hist_field->flags & HIST_FIELD_FL_GRAPH) 1725 flags_str = "graph"; 1726 else if (hist_field->flags & HIST_FIELD_FL_STACKTRACE) 1727 flags_str = "stacktrace"; 1728 1729 return flags_str; 1730 } 1731 1732 static void expr_field_str(struct hist_field *field, char *expr) 1733 { 1734 if (field->flags & HIST_FIELD_FL_VAR_REF) 1735 strcat(expr, "$"); 1736 else if (field->flags & HIST_FIELD_FL_CONST) { 1737 char str[HIST_CONST_DIGITS_MAX]; 1738 1739 snprintf(str, HIST_CONST_DIGITS_MAX, "%llu", field->constant); 1740 strcat(expr, str); 1741 } 1742 1743 strcat(expr, hist_field_name(field, 0)); 1744 1745 if (field->flags && !(field->flags & HIST_FIELD_FL_VAR_REF)) { 1746 const char *flags_str = get_hist_field_flags(field); 1747 1748 if (flags_str) { 1749 strcat(expr, "."); 1750 strcat(expr, flags_str); 1751 } 1752 } 1753 } 1754 1755 static char *expr_str(struct hist_field *field, unsigned int level) 1756 { 1757 char *expr; 1758 1759 if (level > 1) 1760 return NULL; 1761 1762 expr = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL); 1763 if (!expr) 1764 return NULL; 1765 1766 if (!field->operands[0]) { 1767 expr_field_str(field, expr); 1768 return expr; 1769 } 1770 1771 if (field->operator == FIELD_OP_UNARY_MINUS) { 1772 char *subexpr; 1773 1774 strcat(expr, "-("); 1775 subexpr = expr_str(field->operands[0], ++level); 1776 if (!subexpr) { 1777 kfree(expr); 1778 return NULL; 1779 } 1780 strcat(expr, subexpr); 1781 strcat(expr, ")"); 1782 1783 kfree(subexpr); 1784 1785 return expr; 1786 } 1787 1788 expr_field_str(field->operands[0], expr); 1789 1790 switch (field->operator) { 1791 case FIELD_OP_MINUS: 1792 strcat(expr, "-"); 1793 break; 1794 case FIELD_OP_PLUS: 1795 strcat(expr, "+"); 1796 break; 1797 case FIELD_OP_DIV: 1798 strcat(expr, "/"); 1799 break; 1800 case FIELD_OP_MULT: 1801 strcat(expr, "*"); 1802 break; 1803 default: 1804 kfree(expr); 1805 return NULL; 1806 } 1807 1808 expr_field_str(field->operands[1], expr); 1809 1810 return expr; 1811 } 1812 1813 /* 1814 * If field_op != FIELD_OP_NONE, *sep points to the root operator 1815 * of the expression tree to be evaluated. 1816 */ 1817 static int contains_operator(char *str, char **sep) 1818 { 1819 enum field_op_id field_op = FIELD_OP_NONE; 1820 char *minus_op, *plus_op, *div_op, *mult_op; 1821 1822 1823 /* 1824 * Report the last occurrence of the operators first, so that the 1825 * expression is evaluated left to right. This is important since 1826 * subtraction and division are not associative. 1827 * 1828 * e.g 1829 * 64/8/4/2 is 1, i.e 64/8/4/2 = ((64/8)/4)/2 1830 * 14-7-5-2 is 0, i.e 14-7-5-2 = ((14-7)-5)-2 1831 */ 1832 1833 /* 1834 * First, find lower precedence addition and subtraction 1835 * since the expression will be evaluated recursively. 1836 */ 1837 minus_op = strrchr(str, '-'); 1838 if (minus_op) { 1839 /* 1840 * Unary minus is not supported in sub-expressions. If 1841 * present, it is always the next root operator. 1842 */ 1843 if (minus_op == str) { 1844 field_op = FIELD_OP_UNARY_MINUS; 1845 goto out; 1846 } 1847 1848 field_op = FIELD_OP_MINUS; 1849 } 1850 1851 plus_op = strrchr(str, '+'); 1852 if (plus_op || minus_op) { 1853 /* 1854 * For operators of the same precedence use to rightmost as the 1855 * root, so that the expression is evaluated left to right. 1856 */ 1857 if (plus_op > minus_op) 1858 field_op = FIELD_OP_PLUS; 1859 goto out; 1860 } 1861 1862 /* 1863 * Multiplication and division have higher precedence than addition and 1864 * subtraction. 1865 */ 1866 div_op = strrchr(str, '/'); 1867 if (div_op) 1868 field_op = FIELD_OP_DIV; 1869 1870 mult_op = strrchr(str, '*'); 1871 /* 1872 * For operators of the same precedence use to rightmost as the 1873 * root, so that the expression is evaluated left to right. 1874 */ 1875 if (mult_op > div_op) 1876 field_op = FIELD_OP_MULT; 1877 1878 out: 1879 if (sep) { 1880 switch (field_op) { 1881 case FIELD_OP_UNARY_MINUS: 1882 case FIELD_OP_MINUS: 1883 *sep = minus_op; 1884 break; 1885 case FIELD_OP_PLUS: 1886 *sep = plus_op; 1887 break; 1888 case FIELD_OP_DIV: 1889 *sep = div_op; 1890 break; 1891 case FIELD_OP_MULT: 1892 *sep = mult_op; 1893 break; 1894 case FIELD_OP_NONE: 1895 default: 1896 *sep = NULL; 1897 break; 1898 } 1899 } 1900 1901 return field_op; 1902 } 1903 1904 static void get_hist_field(struct hist_field *hist_field) 1905 { 1906 hist_field->ref++; 1907 } 1908 1909 static void __destroy_hist_field(struct hist_field *hist_field) 1910 { 1911 if (--hist_field->ref > 1) 1912 return; 1913 1914 kfree(hist_field->var.name); 1915 kfree(hist_field->name); 1916 1917 /* Can likely be a const */ 1918 kfree_const(hist_field->type); 1919 1920 kfree(hist_field->system); 1921 kfree(hist_field->event_name); 1922 1923 kfree(hist_field); 1924 } 1925 1926 static void destroy_hist_field(struct hist_field *hist_field, 1927 unsigned int level) 1928 { 1929 unsigned int i; 1930 1931 if (level > 3) 1932 return; 1933 1934 if (!hist_field) 1935 return; 1936 1937 if (hist_field->flags & HIST_FIELD_FL_VAR_REF) 1938 return; /* var refs will be destroyed separately */ 1939 1940 for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++) 1941 destroy_hist_field(hist_field->operands[i], level + 1); 1942 1943 __destroy_hist_field(hist_field); 1944 } 1945 1946 static struct hist_field *create_hist_field(struct hist_trigger_data *hist_data, 1947 struct ftrace_event_field *field, 1948 unsigned long flags, 1949 char *var_name) 1950 { 1951 struct hist_field *hist_field; 1952 1953 if (field && is_function_field(field)) 1954 return NULL; 1955 1956 hist_field = kzalloc(sizeof(struct hist_field), GFP_KERNEL); 1957 if (!hist_field) 1958 return NULL; 1959 1960 hist_field->ref = 1; 1961 1962 hist_field->hist_data = hist_data; 1963 1964 if (flags & HIST_FIELD_FL_EXPR || flags & HIST_FIELD_FL_ALIAS) 1965 goto out; /* caller will populate */ 1966 1967 if (flags & HIST_FIELD_FL_VAR_REF) { 1968 hist_field->fn_num = HIST_FIELD_FN_VAR_REF; 1969 goto out; 1970 } 1971 1972 if (flags & HIST_FIELD_FL_HITCOUNT) { 1973 hist_field->fn_num = HIST_FIELD_FN_COUNTER; 1974 hist_field->size = sizeof(u64); 1975 hist_field->type = "u64"; 1976 goto out; 1977 } 1978 1979 if (flags & HIST_FIELD_FL_CONST) { 1980 hist_field->fn_num = HIST_FIELD_FN_CONST; 1981 hist_field->size = sizeof(u64); 1982 hist_field->type = kstrdup("u64", GFP_KERNEL); 1983 if (!hist_field->type) 1984 goto free; 1985 goto out; 1986 } 1987 1988 if (flags & HIST_FIELD_FL_STACKTRACE) { 1989 if (field) 1990 hist_field->fn_num = HIST_FIELD_FN_STACK; 1991 else 1992 hist_field->fn_num = HIST_FIELD_FN_NOP; 1993 hist_field->size = HIST_STACKTRACE_SIZE; 1994 hist_field->type = kstrdup_const("unsigned long[]", GFP_KERNEL); 1995 if (!hist_field->type) 1996 goto free; 1997 goto out; 1998 } 1999 2000 if (flags & (HIST_FIELD_FL_LOG2 | HIST_FIELD_FL_BUCKET)) { 2001 unsigned long fl = flags & ~(HIST_FIELD_FL_LOG2 | HIST_FIELD_FL_BUCKET); 2002 hist_field->fn_num = flags & HIST_FIELD_FL_LOG2 ? HIST_FIELD_FN_LOG2 : 2003 HIST_FIELD_FN_BUCKET; 2004 hist_field->operands[0] = create_hist_field(hist_data, field, fl, NULL); 2005 if (!hist_field->operands[0]) 2006 goto free; 2007 hist_field->size = hist_field->operands[0]->size; 2008 hist_field->type = kstrdup_const(hist_field->operands[0]->type, GFP_KERNEL); 2009 if (!hist_field->type) 2010 goto free; 2011 goto out; 2012 } 2013 2014 if (flags & HIST_FIELD_FL_TIMESTAMP) { 2015 hist_field->fn_num = HIST_FIELD_FN_TIMESTAMP; 2016 hist_field->size = sizeof(u64); 2017 hist_field->type = "u64"; 2018 goto out; 2019 } 2020 2021 if (flags & HIST_FIELD_FL_CPU) { 2022 hist_field->fn_num = HIST_FIELD_FN_CPU; 2023 hist_field->size = sizeof(int); 2024 hist_field->type = "unsigned int"; 2025 goto out; 2026 } 2027 2028 if (WARN_ON_ONCE(!field)) 2029 goto out; 2030 2031 /* Pointers to strings are just pointers and dangerous to dereference */ 2032 if (is_string_field(field) && 2033 (field->filter_type != FILTER_PTR_STRING)) { 2034 flags |= HIST_FIELD_FL_STRING; 2035 2036 hist_field->size = MAX_FILTER_STR_VAL; 2037 hist_field->type = kstrdup_const(field->type, GFP_KERNEL); 2038 if (!hist_field->type) 2039 goto free; 2040 2041 if (field->filter_type == FILTER_STATIC_STRING) { 2042 hist_field->fn_num = HIST_FIELD_FN_STRING; 2043 hist_field->size = field->size; 2044 } else if (field->filter_type == FILTER_DYN_STRING) { 2045 hist_field->fn_num = HIST_FIELD_FN_DYNSTRING; 2046 } else if (field->filter_type == FILTER_RDYN_STRING) 2047 hist_field->fn_num = HIST_FIELD_FN_RELDYNSTRING; 2048 else 2049 hist_field->fn_num = HIST_FIELD_FN_PSTRING; 2050 } else { 2051 hist_field->size = field->size; 2052 hist_field->is_signed = field->is_signed; 2053 hist_field->type = kstrdup_const(field->type, GFP_KERNEL); 2054 if (!hist_field->type) 2055 goto free; 2056 2057 hist_field->fn_num = select_value_fn(field->size, 2058 field->is_signed); 2059 if (hist_field->fn_num == HIST_FIELD_FN_NOP) { 2060 destroy_hist_field(hist_field, 0); 2061 return NULL; 2062 } 2063 } 2064 out: 2065 hist_field->field = field; 2066 hist_field->flags = flags; 2067 2068 if (var_name) { 2069 hist_field->var.name = kstrdup(var_name, GFP_KERNEL); 2070 if (!hist_field->var.name) 2071 goto free; 2072 } 2073 2074 return hist_field; 2075 free: 2076 destroy_hist_field(hist_field, 0); 2077 return NULL; 2078 } 2079 2080 static void destroy_hist_fields(struct hist_trigger_data *hist_data) 2081 { 2082 unsigned int i; 2083 2084 for (i = 0; i < HIST_FIELDS_MAX; i++) { 2085 if (hist_data->fields[i]) { 2086 destroy_hist_field(hist_data->fields[i], 0); 2087 hist_data->fields[i] = NULL; 2088 } 2089 } 2090 2091 for (i = 0; i < hist_data->n_var_refs; i++) { 2092 WARN_ON(!(hist_data->var_refs[i]->flags & HIST_FIELD_FL_VAR_REF)); 2093 __destroy_hist_field(hist_data->var_refs[i]); 2094 hist_data->var_refs[i] = NULL; 2095 } 2096 } 2097 2098 static int init_var_ref(struct hist_field *ref_field, 2099 struct hist_field *var_field, 2100 char *system, char *event_name) 2101 { 2102 int err = 0; 2103 2104 ref_field->var.idx = var_field->var.idx; 2105 ref_field->var.hist_data = var_field->hist_data; 2106 ref_field->size = var_field->size; 2107 ref_field->is_signed = var_field->is_signed; 2108 ref_field->flags |= var_field->flags & 2109 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS); 2110 2111 if (system) { 2112 ref_field->system = kstrdup(system, GFP_KERNEL); 2113 if (!ref_field->system) 2114 return -ENOMEM; 2115 } 2116 2117 if (event_name) { 2118 ref_field->event_name = kstrdup(event_name, GFP_KERNEL); 2119 if (!ref_field->event_name) { 2120 err = -ENOMEM; 2121 goto free; 2122 } 2123 } 2124 2125 if (var_field->var.name) { 2126 ref_field->name = kstrdup(var_field->var.name, GFP_KERNEL); 2127 if (!ref_field->name) { 2128 err = -ENOMEM; 2129 goto free; 2130 } 2131 } else if (var_field->name) { 2132 ref_field->name = kstrdup(var_field->name, GFP_KERNEL); 2133 if (!ref_field->name) { 2134 err = -ENOMEM; 2135 goto free; 2136 } 2137 } 2138 2139 ref_field->type = kstrdup_const(var_field->type, GFP_KERNEL); 2140 if (!ref_field->type) { 2141 err = -ENOMEM; 2142 goto free; 2143 } 2144 out: 2145 return err; 2146 free: 2147 kfree(ref_field->system); 2148 ref_field->system = NULL; 2149 kfree(ref_field->event_name); 2150 ref_field->event_name = NULL; 2151 kfree(ref_field->name); 2152 ref_field->name = NULL; 2153 2154 goto out; 2155 } 2156 2157 static int find_var_ref_idx(struct hist_trigger_data *hist_data, 2158 struct hist_field *var_field) 2159 { 2160 struct hist_field *ref_field; 2161 int i; 2162 2163 for (i = 0; i < hist_data->n_var_refs; i++) { 2164 ref_field = hist_data->var_refs[i]; 2165 if (ref_field->var.idx == var_field->var.idx && 2166 ref_field->var.hist_data == var_field->hist_data) 2167 return i; 2168 } 2169 2170 return -ENOENT; 2171 } 2172 2173 /** 2174 * create_var_ref - Create a variable reference and attach it to trigger 2175 * @hist_data: The trigger that will be referencing the variable 2176 * @var_field: The VAR field to create a reference to 2177 * @system: The optional system string 2178 * @event_name: The optional event_name string 2179 * 2180 * Given a variable hist_field, create a VAR_REF hist_field that 2181 * represents a reference to it. 2182 * 2183 * This function also adds the reference to the trigger that 2184 * now references the variable. 2185 * 2186 * Return: The VAR_REF field if successful, NULL if not 2187 */ 2188 static struct hist_field *create_var_ref(struct hist_trigger_data *hist_data, 2189 struct hist_field *var_field, 2190 char *system, char *event_name) 2191 { 2192 unsigned long flags = HIST_FIELD_FL_VAR_REF; 2193 struct hist_field *ref_field; 2194 int i; 2195 2196 /* Check if the variable already exists */ 2197 for (i = 0; i < hist_data->n_var_refs; i++) { 2198 ref_field = hist_data->var_refs[i]; 2199 if (ref_field->var.idx == var_field->var.idx && 2200 ref_field->var.hist_data == var_field->hist_data) { 2201 get_hist_field(ref_field); 2202 return ref_field; 2203 } 2204 } 2205 /* Sanity check to avoid out-of-bound write on 'hist_data->var_refs' */ 2206 if (hist_data->n_var_refs >= TRACING_MAP_VARS_MAX) 2207 return NULL; 2208 ref_field = create_hist_field(var_field->hist_data, NULL, flags, NULL); 2209 if (ref_field) { 2210 if (init_var_ref(ref_field, var_field, system, event_name)) { 2211 destroy_hist_field(ref_field, 0); 2212 return NULL; 2213 } 2214 2215 hist_data->var_refs[hist_data->n_var_refs] = ref_field; 2216 ref_field->var_ref_idx = hist_data->n_var_refs++; 2217 } 2218 2219 return ref_field; 2220 } 2221 2222 static bool is_var_ref(char *var_name) 2223 { 2224 if (!var_name || strlen(var_name) < 2 || var_name[0] != '$') 2225 return false; 2226 2227 return true; 2228 } 2229 2230 static char *field_name_from_var(struct hist_trigger_data *hist_data, 2231 char *var_name) 2232 { 2233 char *name, *field; 2234 unsigned int i; 2235 2236 for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) { 2237 name = hist_data->attrs->var_defs.name[i]; 2238 2239 if (strcmp(var_name, name) == 0) { 2240 field = hist_data->attrs->var_defs.expr[i]; 2241 if (contains_operator(field, NULL) || is_var_ref(field)) 2242 continue; 2243 return field; 2244 } 2245 } 2246 2247 return NULL; 2248 } 2249 2250 static char *local_field_var_ref(struct hist_trigger_data *hist_data, 2251 char *system, char *event_name, 2252 char *var_name) 2253 { 2254 struct trace_event_call *call; 2255 2256 if (system && event_name) { 2257 call = hist_data->event_file->event_call; 2258 2259 if (strcmp(system, call->class->system) != 0) 2260 return NULL; 2261 2262 if (strcmp(event_name, trace_event_name(call)) != 0) 2263 return NULL; 2264 } 2265 2266 if (!!system != !!event_name) 2267 return NULL; 2268 2269 if (!is_var_ref(var_name)) 2270 return NULL; 2271 2272 var_name++; 2273 2274 return field_name_from_var(hist_data, var_name); 2275 } 2276 2277 static struct hist_field *parse_var_ref(struct hist_trigger_data *hist_data, 2278 char *system, char *event_name, 2279 char *var_name) 2280 { 2281 struct hist_field *var_field = NULL, *ref_field = NULL; 2282 struct trace_array *tr = hist_data->event_file->tr; 2283 2284 if (!is_var_ref(var_name)) 2285 return NULL; 2286 2287 var_name++; 2288 2289 var_field = find_event_var(hist_data, system, event_name, var_name); 2290 if (var_field) 2291 ref_field = create_var_ref(hist_data, var_field, 2292 system, event_name); 2293 2294 if (!ref_field) 2295 hist_err(tr, HIST_ERR_VAR_NOT_FOUND, errpos(var_name)); 2296 2297 return ref_field; 2298 } 2299 2300 static struct ftrace_event_field * 2301 parse_field(struct hist_trigger_data *hist_data, struct trace_event_file *file, 2302 char *field_str, unsigned long *flags, unsigned long *buckets) 2303 { 2304 struct ftrace_event_field *field = NULL; 2305 char *field_name, *modifier, *str; 2306 struct trace_array *tr = file->tr; 2307 2308 modifier = str = kstrdup(field_str, GFP_KERNEL); 2309 if (!modifier) 2310 return ERR_PTR(-ENOMEM); 2311 2312 field_name = strsep(&modifier, "."); 2313 if (modifier) { 2314 if (strcmp(modifier, "hex") == 0) 2315 *flags |= HIST_FIELD_FL_HEX; 2316 else if (strcmp(modifier, "sym") == 0) 2317 *flags |= HIST_FIELD_FL_SYM; 2318 /* 2319 * 'sym-offset' occurrences in the trigger string are modified 2320 * to 'symXoffset' to simplify arithmetic expression parsing. 2321 */ 2322 else if (strcmp(modifier, "symXoffset") == 0) 2323 *flags |= HIST_FIELD_FL_SYM_OFFSET; 2324 else if ((strcmp(modifier, "execname") == 0) && 2325 (strcmp(field_name, "common_pid") == 0)) 2326 *flags |= HIST_FIELD_FL_EXECNAME; 2327 else if (strcmp(modifier, "syscall") == 0) 2328 *flags |= HIST_FIELD_FL_SYSCALL; 2329 else if (strcmp(modifier, "stacktrace") == 0) 2330 *flags |= HIST_FIELD_FL_STACKTRACE; 2331 else if (strcmp(modifier, "log2") == 0) 2332 *flags |= HIST_FIELD_FL_LOG2; 2333 else if (strcmp(modifier, "usecs") == 0) 2334 *flags |= HIST_FIELD_FL_TIMESTAMP_USECS; 2335 else if (strncmp(modifier, "bucket", 6) == 0) { 2336 int ret; 2337 2338 modifier += 6; 2339 2340 if (*modifier == 's') 2341 modifier++; 2342 if (*modifier != '=') 2343 goto error; 2344 modifier++; 2345 ret = kstrtoul(modifier, 0, buckets); 2346 if (ret || !(*buckets)) 2347 goto error; 2348 *flags |= HIST_FIELD_FL_BUCKET; 2349 } else if (strncmp(modifier, "percent", 7) == 0) { 2350 if (*flags & (HIST_FIELD_FL_VAR | HIST_FIELD_FL_KEY)) 2351 goto error; 2352 *flags |= HIST_FIELD_FL_PERCENT; 2353 } else if (strncmp(modifier, "graph", 5) == 0) { 2354 if (*flags & (HIST_FIELD_FL_VAR | HIST_FIELD_FL_KEY)) 2355 goto error; 2356 *flags |= HIST_FIELD_FL_GRAPH; 2357 } else { 2358 error: 2359 hist_err(tr, HIST_ERR_BAD_FIELD_MODIFIER, errpos(modifier)); 2360 field = ERR_PTR(-EINVAL); 2361 goto out; 2362 } 2363 } 2364 2365 if (strcmp(field_name, "common_timestamp") == 0) { 2366 *flags |= HIST_FIELD_FL_TIMESTAMP; 2367 hist_data->enable_timestamps = true; 2368 if (*flags & HIST_FIELD_FL_TIMESTAMP_USECS) 2369 hist_data->attrs->ts_in_usecs = true; 2370 } else if (strcmp(field_name, "stacktrace") == 0) { 2371 *flags |= HIST_FIELD_FL_STACKTRACE; 2372 } else if (strcmp(field_name, "common_cpu") == 0) 2373 *flags |= HIST_FIELD_FL_CPU; 2374 else if (strcmp(field_name, "hitcount") == 0) 2375 *flags |= HIST_FIELD_FL_HITCOUNT; 2376 else { 2377 field = trace_find_event_field(file->event_call, field_name); 2378 if (!field || !field->size) { 2379 /* 2380 * For backward compatibility, if field_name 2381 * was "cpu", then we treat this the same as 2382 * common_cpu. This also works for "CPU". 2383 */ 2384 if (field && field->filter_type == FILTER_CPU) { 2385 *flags |= HIST_FIELD_FL_CPU; 2386 } else { 2387 hist_err(tr, HIST_ERR_FIELD_NOT_FOUND, 2388 errpos(field_name)); 2389 field = ERR_PTR(-EINVAL); 2390 goto out; 2391 } 2392 } 2393 } 2394 out: 2395 kfree(str); 2396 2397 return field; 2398 } 2399 2400 static struct hist_field *create_alias(struct hist_trigger_data *hist_data, 2401 struct hist_field *var_ref, 2402 char *var_name) 2403 { 2404 struct hist_field *alias = NULL; 2405 unsigned long flags = HIST_FIELD_FL_ALIAS | HIST_FIELD_FL_VAR; 2406 2407 alias = create_hist_field(hist_data, NULL, flags, var_name); 2408 if (!alias) 2409 return NULL; 2410 2411 alias->fn_num = var_ref->fn_num; 2412 alias->operands[0] = var_ref; 2413 2414 if (init_var_ref(alias, var_ref, var_ref->system, var_ref->event_name)) { 2415 destroy_hist_field(alias, 0); 2416 return NULL; 2417 } 2418 2419 alias->var_ref_idx = var_ref->var_ref_idx; 2420 2421 return alias; 2422 } 2423 2424 static struct hist_field *parse_const(struct hist_trigger_data *hist_data, 2425 char *str, char *var_name, 2426 unsigned long *flags) 2427 { 2428 struct trace_array *tr = hist_data->event_file->tr; 2429 struct hist_field *field = NULL; 2430 u64 constant; 2431 2432 if (kstrtoull(str, 0, &constant)) { 2433 hist_err(tr, HIST_ERR_EXPECT_NUMBER, errpos(str)); 2434 return NULL; 2435 } 2436 2437 *flags |= HIST_FIELD_FL_CONST; 2438 field = create_hist_field(hist_data, NULL, *flags, var_name); 2439 if (!field) 2440 return NULL; 2441 2442 field->constant = constant; 2443 2444 return field; 2445 } 2446 2447 static struct hist_field *parse_atom(struct hist_trigger_data *hist_data, 2448 struct trace_event_file *file, char *str, 2449 unsigned long *flags, char *var_name) 2450 { 2451 char *s, *ref_system = NULL, *ref_event = NULL, *ref_var = str; 2452 struct ftrace_event_field *field = NULL; 2453 struct hist_field *hist_field = NULL; 2454 unsigned long buckets = 0; 2455 int ret = 0; 2456 2457 if (isdigit(str[0])) { 2458 hist_field = parse_const(hist_data, str, var_name, flags); 2459 if (!hist_field) { 2460 ret = -EINVAL; 2461 goto out; 2462 } 2463 return hist_field; 2464 } 2465 2466 s = strchr(str, '.'); 2467 if (s) { 2468 s = strchr(++s, '.'); 2469 if (s) { 2470 ref_system = strsep(&str, "."); 2471 if (!str) { 2472 ret = -EINVAL; 2473 goto out; 2474 } 2475 ref_event = strsep(&str, "."); 2476 if (!str) { 2477 ret = -EINVAL; 2478 goto out; 2479 } 2480 ref_var = str; 2481 } 2482 } 2483 2484 s = local_field_var_ref(hist_data, ref_system, ref_event, ref_var); 2485 if (!s) { 2486 hist_field = parse_var_ref(hist_data, ref_system, 2487 ref_event, ref_var); 2488 if (hist_field) { 2489 if (var_name) { 2490 hist_field = create_alias(hist_data, hist_field, var_name); 2491 if (!hist_field) { 2492 ret = -ENOMEM; 2493 goto out; 2494 } 2495 } 2496 return hist_field; 2497 } 2498 } else 2499 str = s; 2500 2501 field = parse_field(hist_data, file, str, flags, &buckets); 2502 if (IS_ERR(field)) { 2503 ret = PTR_ERR(field); 2504 goto out; 2505 } 2506 2507 hist_field = create_hist_field(hist_data, field, *flags, var_name); 2508 if (!hist_field) { 2509 ret = -ENOMEM; 2510 goto out; 2511 } 2512 hist_field->buckets = buckets; 2513 2514 return hist_field; 2515 out: 2516 return ERR_PTR(ret); 2517 } 2518 2519 static struct hist_field *parse_expr(struct hist_trigger_data *hist_data, 2520 struct trace_event_file *file, 2521 char *str, unsigned long flags, 2522 char *var_name, unsigned int *n_subexprs); 2523 2524 static struct hist_field *parse_unary(struct hist_trigger_data *hist_data, 2525 struct trace_event_file *file, 2526 char *str, unsigned long flags, 2527 char *var_name, unsigned int *n_subexprs) 2528 { 2529 struct hist_field *operand1, *expr = NULL; 2530 unsigned long operand_flags; 2531 int ret = 0; 2532 char *s; 2533 2534 /* Unary minus operator, increment n_subexprs */ 2535 ++*n_subexprs; 2536 2537 /* we support only -(xxx) i.e. explicit parens required */ 2538 2539 if (*n_subexprs > 3) { 2540 hist_err(file->tr, HIST_ERR_TOO_MANY_SUBEXPR, errpos(str)); 2541 ret = -EINVAL; 2542 goto free; 2543 } 2544 2545 str++; /* skip leading '-' */ 2546 2547 s = strchr(str, '('); 2548 if (s) 2549 str++; 2550 else { 2551 ret = -EINVAL; 2552 goto free; 2553 } 2554 2555 s = strrchr(str, ')'); 2556 if (s) { 2557 /* unary minus not supported in sub-expressions */ 2558 if (*(s+1) != '\0') { 2559 hist_err(file->tr, HIST_ERR_UNARY_MINUS_SUBEXPR, 2560 errpos(str)); 2561 ret = -EINVAL; 2562 goto free; 2563 } 2564 *s = '\0'; 2565 } 2566 else { 2567 ret = -EINVAL; /* no closing ')' */ 2568 goto free; 2569 } 2570 2571 flags |= HIST_FIELD_FL_EXPR; 2572 expr = create_hist_field(hist_data, NULL, flags, var_name); 2573 if (!expr) { 2574 ret = -ENOMEM; 2575 goto free; 2576 } 2577 2578 operand_flags = 0; 2579 operand1 = parse_expr(hist_data, file, str, operand_flags, NULL, n_subexprs); 2580 if (IS_ERR(operand1)) { 2581 ret = PTR_ERR(operand1); 2582 goto free; 2583 } 2584 if (operand1->flags & HIST_FIELD_FL_STRING) { 2585 /* String type can not be the operand of unary operator. */ 2586 hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(str)); 2587 destroy_hist_field(operand1, 0); 2588 ret = -EINVAL; 2589 goto free; 2590 } 2591 2592 expr->flags |= operand1->flags & 2593 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS); 2594 expr->fn_num = HIST_FIELD_FN_UMINUS; 2595 expr->operands[0] = operand1; 2596 expr->size = operand1->size; 2597 expr->is_signed = operand1->is_signed; 2598 expr->operator = FIELD_OP_UNARY_MINUS; 2599 expr->name = expr_str(expr, 0); 2600 expr->type = kstrdup_const(operand1->type, GFP_KERNEL); 2601 if (!expr->type) { 2602 ret = -ENOMEM; 2603 goto free; 2604 } 2605 2606 return expr; 2607 free: 2608 destroy_hist_field(expr, 0); 2609 return ERR_PTR(ret); 2610 } 2611 2612 /* 2613 * If the operands are var refs, return pointers the 2614 * variable(s) referenced in var1 and var2, else NULL. 2615 */ 2616 static int check_expr_operands(struct trace_array *tr, 2617 struct hist_field *operand1, 2618 struct hist_field *operand2, 2619 struct hist_field **var1, 2620 struct hist_field **var2) 2621 { 2622 unsigned long operand1_flags = operand1->flags; 2623 unsigned long operand2_flags = operand2->flags; 2624 2625 if ((operand1_flags & HIST_FIELD_FL_VAR_REF) || 2626 (operand1_flags & HIST_FIELD_FL_ALIAS)) { 2627 struct hist_field *var; 2628 2629 var = find_var_field(operand1->var.hist_data, operand1->name); 2630 if (!var) 2631 return -EINVAL; 2632 operand1_flags = var->flags; 2633 *var1 = var; 2634 } 2635 2636 if ((operand2_flags & HIST_FIELD_FL_VAR_REF) || 2637 (operand2_flags & HIST_FIELD_FL_ALIAS)) { 2638 struct hist_field *var; 2639 2640 var = find_var_field(operand2->var.hist_data, operand2->name); 2641 if (!var) 2642 return -EINVAL; 2643 operand2_flags = var->flags; 2644 *var2 = var; 2645 } 2646 2647 if ((operand1_flags & HIST_FIELD_FL_TIMESTAMP_USECS) != 2648 (operand2_flags & HIST_FIELD_FL_TIMESTAMP_USECS)) { 2649 hist_err(tr, HIST_ERR_TIMESTAMP_MISMATCH, 0); 2650 return -EINVAL; 2651 } 2652 2653 return 0; 2654 } 2655 2656 static struct hist_field *parse_expr(struct hist_trigger_data *hist_data, 2657 struct trace_event_file *file, 2658 char *str, unsigned long flags, 2659 char *var_name, unsigned int *n_subexprs) 2660 { 2661 struct hist_field *operand1 = NULL, *operand2 = NULL, *expr = NULL; 2662 struct hist_field *var1 = NULL, *var2 = NULL; 2663 unsigned long operand_flags, operand2_flags; 2664 int field_op, ret = -EINVAL; 2665 char *sep, *operand1_str; 2666 enum hist_field_fn op_fn; 2667 bool combine_consts; 2668 2669 if (*n_subexprs > 3) { 2670 hist_err(file->tr, HIST_ERR_TOO_MANY_SUBEXPR, errpos(str)); 2671 return ERR_PTR(-EINVAL); 2672 } 2673 2674 field_op = contains_operator(str, &sep); 2675 2676 if (field_op == FIELD_OP_NONE) 2677 return parse_atom(hist_data, file, str, &flags, var_name); 2678 2679 if (field_op == FIELD_OP_UNARY_MINUS) 2680 return parse_unary(hist_data, file, str, flags, var_name, n_subexprs); 2681 2682 /* Binary operator found, increment n_subexprs */ 2683 ++*n_subexprs; 2684 2685 /* Split the expression string at the root operator */ 2686 if (!sep) 2687 return ERR_PTR(-EINVAL); 2688 2689 *sep = '\0'; 2690 operand1_str = str; 2691 str = sep+1; 2692 2693 /* Binary operator requires both operands */ 2694 if (*operand1_str == '\0' || *str == '\0') 2695 return ERR_PTR(-EINVAL); 2696 2697 operand_flags = 0; 2698 2699 /* LHS of string is an expression e.g. a+b in a+b+c */ 2700 operand1 = parse_expr(hist_data, file, operand1_str, operand_flags, NULL, n_subexprs); 2701 if (IS_ERR(operand1)) 2702 return ERR_CAST(operand1); 2703 2704 if (operand1->flags & HIST_FIELD_FL_STRING) { 2705 hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(operand1_str)); 2706 ret = -EINVAL; 2707 goto free_op1; 2708 } 2709 2710 /* RHS of string is another expression e.g. c in a+b+c */ 2711 operand_flags = 0; 2712 operand2 = parse_expr(hist_data, file, str, operand_flags, NULL, n_subexprs); 2713 if (IS_ERR(operand2)) { 2714 ret = PTR_ERR(operand2); 2715 goto free_op1; 2716 } 2717 if (operand2->flags & HIST_FIELD_FL_STRING) { 2718 hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(str)); 2719 ret = -EINVAL; 2720 goto free_operands; 2721 } 2722 2723 switch (field_op) { 2724 case FIELD_OP_MINUS: 2725 op_fn = HIST_FIELD_FN_MINUS; 2726 break; 2727 case FIELD_OP_PLUS: 2728 op_fn = HIST_FIELD_FN_PLUS; 2729 break; 2730 case FIELD_OP_DIV: 2731 op_fn = HIST_FIELD_FN_DIV; 2732 break; 2733 case FIELD_OP_MULT: 2734 op_fn = HIST_FIELD_FN_MULT; 2735 break; 2736 default: 2737 ret = -EINVAL; 2738 goto free_operands; 2739 } 2740 2741 ret = check_expr_operands(file->tr, operand1, operand2, &var1, &var2); 2742 if (ret) 2743 goto free_operands; 2744 2745 operand_flags = var1 ? var1->flags : operand1->flags; 2746 operand2_flags = var2 ? var2->flags : operand2->flags; 2747 2748 /* 2749 * If both operands are constant, the expression can be 2750 * collapsed to a single constant. 2751 */ 2752 combine_consts = operand_flags & operand2_flags & HIST_FIELD_FL_CONST; 2753 2754 flags |= combine_consts ? HIST_FIELD_FL_CONST : HIST_FIELD_FL_EXPR; 2755 2756 flags |= operand1->flags & 2757 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS); 2758 2759 expr = create_hist_field(hist_data, NULL, flags, var_name); 2760 if (!expr) { 2761 ret = -ENOMEM; 2762 goto free_operands; 2763 } 2764 2765 operand1->read_once = true; 2766 operand2->read_once = true; 2767 2768 /* The operands are now owned and free'd by 'expr' */ 2769 expr->operands[0] = operand1; 2770 expr->operands[1] = operand2; 2771 2772 if (field_op == FIELD_OP_DIV && 2773 operand2_flags & HIST_FIELD_FL_CONST) { 2774 u64 divisor = var2 ? var2->constant : operand2->constant; 2775 2776 if (!divisor) { 2777 hist_err(file->tr, HIST_ERR_DIVISION_BY_ZERO, errpos(str)); 2778 ret = -EDOM; 2779 goto free_expr; 2780 } 2781 2782 /* 2783 * Copy the divisor here so we don't have to look it up 2784 * later if this is a var ref 2785 */ 2786 operand2->constant = divisor; 2787 op_fn = hist_field_get_div_fn(operand2); 2788 } 2789 2790 expr->fn_num = op_fn; 2791 2792 if (combine_consts) { 2793 if (var1) 2794 expr->operands[0] = var1; 2795 if (var2) 2796 expr->operands[1] = var2; 2797 2798 expr->constant = hist_fn_call(expr, NULL, NULL, NULL, NULL); 2799 expr->fn_num = HIST_FIELD_FN_CONST; 2800 2801 expr->operands[0] = NULL; 2802 expr->operands[1] = NULL; 2803 2804 /* 2805 * var refs won't be destroyed immediately 2806 * See: destroy_hist_field() 2807 */ 2808 destroy_hist_field(operand2, 0); 2809 destroy_hist_field(operand1, 0); 2810 2811 expr->name = expr_str(expr, 0); 2812 } else { 2813 /* The operand sizes should be the same, so just pick one */ 2814 expr->size = operand1->size; 2815 expr->is_signed = operand1->is_signed; 2816 2817 expr->operator = field_op; 2818 expr->type = kstrdup_const(operand1->type, GFP_KERNEL); 2819 if (!expr->type) { 2820 ret = -ENOMEM; 2821 goto free_expr; 2822 } 2823 2824 expr->name = expr_str(expr, 0); 2825 } 2826 2827 return expr; 2828 2829 free_operands: 2830 destroy_hist_field(operand2, 0); 2831 free_op1: 2832 destroy_hist_field(operand1, 0); 2833 return ERR_PTR(ret); 2834 2835 free_expr: 2836 destroy_hist_field(expr, 0); 2837 return ERR_PTR(ret); 2838 } 2839 2840 static char *find_trigger_filter(struct hist_trigger_data *hist_data, 2841 struct trace_event_file *file) 2842 { 2843 struct event_trigger_data *test; 2844 2845 lockdep_assert_held(&event_mutex); 2846 2847 list_for_each_entry(test, &file->triggers, list) { 2848 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 2849 if (test->private_data == hist_data) 2850 return test->filter_str; 2851 } 2852 } 2853 2854 return NULL; 2855 } 2856 2857 static struct event_command trigger_hist_cmd; 2858 static int event_hist_trigger_parse(struct event_command *cmd_ops, 2859 struct trace_event_file *file, 2860 char *glob, char *cmd, 2861 char *param_and_filter); 2862 2863 static bool compatible_keys(struct hist_trigger_data *target_hist_data, 2864 struct hist_trigger_data *hist_data, 2865 unsigned int n_keys) 2866 { 2867 struct hist_field *target_hist_field, *hist_field; 2868 unsigned int n, i, j; 2869 2870 if (hist_data->n_fields - hist_data->n_vals != n_keys) 2871 return false; 2872 2873 i = hist_data->n_vals; 2874 j = target_hist_data->n_vals; 2875 2876 for (n = 0; n < n_keys; n++) { 2877 hist_field = hist_data->fields[i + n]; 2878 target_hist_field = target_hist_data->fields[j + n]; 2879 2880 if (strcmp(hist_field->type, target_hist_field->type) != 0) 2881 return false; 2882 if (hist_field->size != target_hist_field->size) 2883 return false; 2884 if (hist_field->is_signed != target_hist_field->is_signed) 2885 return false; 2886 } 2887 2888 return true; 2889 } 2890 2891 static struct hist_trigger_data * 2892 find_compatible_hist(struct hist_trigger_data *target_hist_data, 2893 struct trace_event_file *file) 2894 { 2895 struct hist_trigger_data *hist_data; 2896 struct event_trigger_data *test; 2897 unsigned int n_keys; 2898 2899 lockdep_assert_held(&event_mutex); 2900 2901 n_keys = target_hist_data->n_fields - target_hist_data->n_vals; 2902 2903 list_for_each_entry(test, &file->triggers, list) { 2904 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 2905 hist_data = test->private_data; 2906 2907 if (compatible_keys(target_hist_data, hist_data, n_keys)) 2908 return hist_data; 2909 } 2910 } 2911 2912 return NULL; 2913 } 2914 2915 static struct trace_event_file *event_file(struct trace_array *tr, 2916 char *system, char *event_name) 2917 { 2918 struct trace_event_file *file; 2919 2920 file = __find_event_file(tr, system, event_name); 2921 if (!file) 2922 return ERR_PTR(-EINVAL); 2923 2924 return file; 2925 } 2926 2927 static struct hist_field * 2928 find_synthetic_field_var(struct hist_trigger_data *target_hist_data, 2929 char *system, char *event_name, char *field_name) 2930 { 2931 struct hist_field *event_var; 2932 char *synthetic_name; 2933 2934 synthetic_name = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL); 2935 if (!synthetic_name) 2936 return ERR_PTR(-ENOMEM); 2937 2938 strcpy(synthetic_name, "synthetic_"); 2939 strcat(synthetic_name, field_name); 2940 2941 event_var = find_event_var(target_hist_data, system, event_name, synthetic_name); 2942 2943 kfree(synthetic_name); 2944 2945 return event_var; 2946 } 2947 2948 /** 2949 * create_field_var_hist - Automatically create a histogram and var for a field 2950 * @target_hist_data: The target hist trigger 2951 * @subsys_name: Optional subsystem name 2952 * @event_name: Optional event name 2953 * @field_name: The name of the field (and the resulting variable) 2954 * 2955 * Hist trigger actions fetch data from variables, not directly from 2956 * events. However, for convenience, users are allowed to directly 2957 * specify an event field in an action, which will be automatically 2958 * converted into a variable on their behalf. 2959 * 2960 * If a user specifies a field on an event that isn't the event the 2961 * histogram currently being defined (the target event histogram), the 2962 * only way that can be accomplished is if a new hist trigger is 2963 * created and the field variable defined on that. 2964 * 2965 * This function creates a new histogram compatible with the target 2966 * event (meaning a histogram with the same key as the target 2967 * histogram), and creates a variable for the specified field, but 2968 * with 'synthetic_' prepended to the variable name in order to avoid 2969 * collision with normal field variables. 2970 * 2971 * Return: The variable created for the field. 2972 */ 2973 static struct hist_field * 2974 create_field_var_hist(struct hist_trigger_data *target_hist_data, 2975 char *subsys_name, char *event_name, char *field_name) 2976 { 2977 struct trace_array *tr = target_hist_data->event_file->tr; 2978 struct hist_trigger_data *hist_data; 2979 unsigned int i, n, first = true; 2980 struct field_var_hist *var_hist; 2981 struct trace_event_file *file; 2982 struct hist_field *key_field; 2983 struct hist_field *event_var; 2984 char *saved_filter; 2985 char *cmd; 2986 int ret; 2987 2988 if (target_hist_data->n_field_var_hists >= SYNTH_FIELDS_MAX) { 2989 hist_err(tr, HIST_ERR_TOO_MANY_FIELD_VARS, errpos(field_name)); 2990 return ERR_PTR(-EINVAL); 2991 } 2992 2993 file = event_file(tr, subsys_name, event_name); 2994 2995 if (IS_ERR(file)) { 2996 hist_err(tr, HIST_ERR_EVENT_FILE_NOT_FOUND, errpos(field_name)); 2997 ret = PTR_ERR(file); 2998 return ERR_PTR(ret); 2999 } 3000 3001 /* 3002 * Look for a histogram compatible with target. We'll use the 3003 * found histogram specification to create a new matching 3004 * histogram with our variable on it. target_hist_data is not 3005 * yet a registered histogram so we can't use that. 3006 */ 3007 hist_data = find_compatible_hist(target_hist_data, file); 3008 if (!hist_data) { 3009 hist_err(tr, HIST_ERR_HIST_NOT_FOUND, errpos(field_name)); 3010 return ERR_PTR(-EINVAL); 3011 } 3012 3013 /* See if a synthetic field variable has already been created */ 3014 event_var = find_synthetic_field_var(target_hist_data, subsys_name, 3015 event_name, field_name); 3016 if (!IS_ERR_OR_NULL(event_var)) 3017 return event_var; 3018 3019 var_hist = kzalloc(sizeof(*var_hist), GFP_KERNEL); 3020 if (!var_hist) 3021 return ERR_PTR(-ENOMEM); 3022 3023 cmd = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL); 3024 if (!cmd) { 3025 kfree(var_hist); 3026 return ERR_PTR(-ENOMEM); 3027 } 3028 3029 /* Use the same keys as the compatible histogram */ 3030 strcat(cmd, "keys="); 3031 3032 for_each_hist_key_field(i, hist_data) { 3033 key_field = hist_data->fields[i]; 3034 if (!first) 3035 strcat(cmd, ","); 3036 strcat(cmd, key_field->field->name); 3037 first = false; 3038 } 3039 3040 /* Create the synthetic field variable specification */ 3041 strcat(cmd, ":synthetic_"); 3042 strcat(cmd, field_name); 3043 strcat(cmd, "="); 3044 strcat(cmd, field_name); 3045 3046 /* Use the same filter as the compatible histogram */ 3047 saved_filter = find_trigger_filter(hist_data, file); 3048 if (saved_filter) { 3049 strcat(cmd, " if "); 3050 strcat(cmd, saved_filter); 3051 } 3052 3053 var_hist->cmd = kstrdup(cmd, GFP_KERNEL); 3054 if (!var_hist->cmd) { 3055 kfree(cmd); 3056 kfree(var_hist); 3057 return ERR_PTR(-ENOMEM); 3058 } 3059 3060 /* Save the compatible histogram information */ 3061 var_hist->hist_data = hist_data; 3062 3063 /* Create the new histogram with our variable */ 3064 ret = event_hist_trigger_parse(&trigger_hist_cmd, file, 3065 "", "hist", cmd); 3066 if (ret) { 3067 kfree(cmd); 3068 kfree(var_hist->cmd); 3069 kfree(var_hist); 3070 hist_err(tr, HIST_ERR_HIST_CREATE_FAIL, errpos(field_name)); 3071 return ERR_PTR(ret); 3072 } 3073 3074 kfree(cmd); 3075 3076 /* If we can't find the variable, something went wrong */ 3077 event_var = find_synthetic_field_var(target_hist_data, subsys_name, 3078 event_name, field_name); 3079 if (IS_ERR_OR_NULL(event_var)) { 3080 kfree(var_hist->cmd); 3081 kfree(var_hist); 3082 hist_err(tr, HIST_ERR_SYNTH_VAR_NOT_FOUND, errpos(field_name)); 3083 return ERR_PTR(-EINVAL); 3084 } 3085 3086 n = target_hist_data->n_field_var_hists; 3087 target_hist_data->field_var_hists[n] = var_hist; 3088 target_hist_data->n_field_var_hists++; 3089 3090 return event_var; 3091 } 3092 3093 static struct hist_field * 3094 find_target_event_var(struct hist_trigger_data *hist_data, 3095 char *subsys_name, char *event_name, char *var_name) 3096 { 3097 struct trace_event_file *file = hist_data->event_file; 3098 struct hist_field *hist_field = NULL; 3099 3100 if (subsys_name) { 3101 struct trace_event_call *call; 3102 3103 if (!event_name) 3104 return NULL; 3105 3106 call = file->event_call; 3107 3108 if (strcmp(subsys_name, call->class->system) != 0) 3109 return NULL; 3110 3111 if (strcmp(event_name, trace_event_name(call)) != 0) 3112 return NULL; 3113 } 3114 3115 hist_field = find_var_field(hist_data, var_name); 3116 3117 return hist_field; 3118 } 3119 3120 static inline void __update_field_vars(struct tracing_map_elt *elt, 3121 struct trace_buffer *buffer, 3122 struct ring_buffer_event *rbe, 3123 void *rec, 3124 struct field_var **field_vars, 3125 unsigned int n_field_vars, 3126 unsigned int field_var_str_start) 3127 { 3128 struct hist_elt_data *elt_data = elt->private_data; 3129 unsigned int i, j, var_idx; 3130 u64 var_val; 3131 3132 /* Make sure stacktrace can fit in the string variable length */ 3133 BUILD_BUG_ON((HIST_STACKTRACE_DEPTH + 1) * sizeof(long) >= STR_VAR_LEN_MAX); 3134 3135 for (i = 0, j = field_var_str_start; i < n_field_vars; i++) { 3136 struct field_var *field_var = field_vars[i]; 3137 struct hist_field *var = field_var->var; 3138 struct hist_field *val = field_var->val; 3139 3140 var_val = hist_fn_call(val, elt, buffer, rbe, rec); 3141 var_idx = var->var.idx; 3142 3143 if (val->flags & (HIST_FIELD_FL_STRING | 3144 HIST_FIELD_FL_STACKTRACE)) { 3145 char *str = elt_data->field_var_str[j++]; 3146 char *val_str = (char *)(uintptr_t)var_val; 3147 unsigned int size; 3148 3149 if (val->flags & HIST_FIELD_FL_STRING) { 3150 size = min(val->size, STR_VAR_LEN_MAX); 3151 strscpy(str, val_str, size); 3152 } else { 3153 char *stack_start = str + sizeof(unsigned long); 3154 int e; 3155 3156 e = stack_trace_save((void *)stack_start, 3157 HIST_STACKTRACE_DEPTH, 3158 HIST_STACKTRACE_SKIP); 3159 if (e < HIST_STACKTRACE_DEPTH - 1) 3160 ((unsigned long *)stack_start)[e] = 0; 3161 *((unsigned long *)str) = e; 3162 } 3163 var_val = (u64)(uintptr_t)str; 3164 } 3165 tracing_map_set_var(elt, var_idx, var_val); 3166 } 3167 } 3168 3169 static void update_field_vars(struct hist_trigger_data *hist_data, 3170 struct tracing_map_elt *elt, 3171 struct trace_buffer *buffer, 3172 struct ring_buffer_event *rbe, 3173 void *rec) 3174 { 3175 __update_field_vars(elt, buffer, rbe, rec, hist_data->field_vars, 3176 hist_data->n_field_vars, 0); 3177 } 3178 3179 static void save_track_data_vars(struct hist_trigger_data *hist_data, 3180 struct tracing_map_elt *elt, 3181 struct trace_buffer *buffer, void *rec, 3182 struct ring_buffer_event *rbe, void *key, 3183 struct action_data *data, u64 *var_ref_vals) 3184 { 3185 __update_field_vars(elt, buffer, rbe, rec, hist_data->save_vars, 3186 hist_data->n_save_vars, hist_data->n_field_var_str); 3187 } 3188 3189 static struct hist_field *create_var(struct hist_trigger_data *hist_data, 3190 struct trace_event_file *file, 3191 char *name, int size, const char *type) 3192 { 3193 struct hist_field *var; 3194 int idx; 3195 3196 if (find_var(hist_data, file, name) && !hist_data->remove) { 3197 var = ERR_PTR(-EINVAL); 3198 goto out; 3199 } 3200 3201 var = kzalloc(sizeof(struct hist_field), GFP_KERNEL); 3202 if (!var) { 3203 var = ERR_PTR(-ENOMEM); 3204 goto out; 3205 } 3206 3207 idx = tracing_map_add_var(hist_data->map); 3208 if (idx < 0) { 3209 kfree(var); 3210 var = ERR_PTR(-EINVAL); 3211 goto out; 3212 } 3213 3214 var->ref = 1; 3215 var->flags = HIST_FIELD_FL_VAR; 3216 var->var.idx = idx; 3217 var->var.hist_data = var->hist_data = hist_data; 3218 var->size = size; 3219 var->var.name = kstrdup(name, GFP_KERNEL); 3220 var->type = kstrdup_const(type, GFP_KERNEL); 3221 if (!var->var.name || !var->type) { 3222 kfree_const(var->type); 3223 kfree(var->var.name); 3224 kfree(var); 3225 var = ERR_PTR(-ENOMEM); 3226 } 3227 out: 3228 return var; 3229 } 3230 3231 static struct field_var *create_field_var(struct hist_trigger_data *hist_data, 3232 struct trace_event_file *file, 3233 char *field_name) 3234 { 3235 struct hist_field *val = NULL, *var = NULL; 3236 unsigned long flags = HIST_FIELD_FL_VAR; 3237 struct trace_array *tr = file->tr; 3238 struct field_var *field_var; 3239 int ret = 0; 3240 3241 if (hist_data->n_field_vars >= SYNTH_FIELDS_MAX) { 3242 hist_err(tr, HIST_ERR_TOO_MANY_FIELD_VARS, errpos(field_name)); 3243 ret = -EINVAL; 3244 goto err; 3245 } 3246 3247 val = parse_atom(hist_data, file, field_name, &flags, NULL); 3248 if (IS_ERR(val)) { 3249 hist_err(tr, HIST_ERR_FIELD_VAR_PARSE_FAIL, errpos(field_name)); 3250 ret = PTR_ERR(val); 3251 goto err; 3252 } 3253 3254 var = create_var(hist_data, file, field_name, val->size, val->type); 3255 if (IS_ERR(var)) { 3256 hist_err(tr, HIST_ERR_VAR_CREATE_FIND_FAIL, errpos(field_name)); 3257 kfree(val); 3258 ret = PTR_ERR(var); 3259 goto err; 3260 } 3261 3262 field_var = kzalloc(sizeof(struct field_var), GFP_KERNEL); 3263 if (!field_var) { 3264 kfree(val); 3265 kfree(var); 3266 ret = -ENOMEM; 3267 goto err; 3268 } 3269 3270 field_var->var = var; 3271 field_var->val = val; 3272 out: 3273 return field_var; 3274 err: 3275 field_var = ERR_PTR(ret); 3276 goto out; 3277 } 3278 3279 /** 3280 * create_target_field_var - Automatically create a variable for a field 3281 * @target_hist_data: The target hist trigger 3282 * @subsys_name: Optional subsystem name 3283 * @event_name: Optional event name 3284 * @var_name: The name of the field (and the resulting variable) 3285 * 3286 * Hist trigger actions fetch data from variables, not directly from 3287 * events. However, for convenience, users are allowed to directly 3288 * specify an event field in an action, which will be automatically 3289 * converted into a variable on their behalf. 3290 * 3291 * This function creates a field variable with the name var_name on 3292 * the hist trigger currently being defined on the target event. If 3293 * subsys_name and event_name are specified, this function simply 3294 * verifies that they do in fact match the target event subsystem and 3295 * event name. 3296 * 3297 * Return: The variable created for the field. 3298 */ 3299 static struct field_var * 3300 create_target_field_var(struct hist_trigger_data *target_hist_data, 3301 char *subsys_name, char *event_name, char *var_name) 3302 { 3303 struct trace_event_file *file = target_hist_data->event_file; 3304 3305 if (subsys_name) { 3306 struct trace_event_call *call; 3307 3308 if (!event_name) 3309 return NULL; 3310 3311 call = file->event_call; 3312 3313 if (strcmp(subsys_name, call->class->system) != 0) 3314 return NULL; 3315 3316 if (strcmp(event_name, trace_event_name(call)) != 0) 3317 return NULL; 3318 } 3319 3320 return create_field_var(target_hist_data, file, var_name); 3321 } 3322 3323 static bool check_track_val_max(u64 track_val, u64 var_val) 3324 { 3325 if (var_val <= track_val) 3326 return false; 3327 3328 return true; 3329 } 3330 3331 static bool check_track_val_changed(u64 track_val, u64 var_val) 3332 { 3333 if (var_val == track_val) 3334 return false; 3335 3336 return true; 3337 } 3338 3339 static u64 get_track_val(struct hist_trigger_data *hist_data, 3340 struct tracing_map_elt *elt, 3341 struct action_data *data) 3342 { 3343 unsigned int track_var_idx = data->track_data.track_var->var.idx; 3344 u64 track_val; 3345 3346 track_val = tracing_map_read_var(elt, track_var_idx); 3347 3348 return track_val; 3349 } 3350 3351 static void save_track_val(struct hist_trigger_data *hist_data, 3352 struct tracing_map_elt *elt, 3353 struct action_data *data, u64 var_val) 3354 { 3355 unsigned int track_var_idx = data->track_data.track_var->var.idx; 3356 3357 tracing_map_set_var(elt, track_var_idx, var_val); 3358 } 3359 3360 static void save_track_data(struct hist_trigger_data *hist_data, 3361 struct tracing_map_elt *elt, 3362 struct trace_buffer *buffer, void *rec, 3363 struct ring_buffer_event *rbe, void *key, 3364 struct action_data *data, u64 *var_ref_vals) 3365 { 3366 if (data->track_data.save_data) 3367 data->track_data.save_data(hist_data, elt, buffer, rec, rbe, 3368 key, data, var_ref_vals); 3369 } 3370 3371 static bool check_track_val(struct tracing_map_elt *elt, 3372 struct action_data *data, 3373 u64 var_val) 3374 { 3375 struct hist_trigger_data *hist_data; 3376 u64 track_val; 3377 3378 hist_data = data->track_data.track_var->hist_data; 3379 track_val = get_track_val(hist_data, elt, data); 3380 3381 return data->track_data.check_val(track_val, var_val); 3382 } 3383 3384 #ifdef CONFIG_TRACER_SNAPSHOT 3385 static bool cond_snapshot_update(struct trace_array *tr, void *cond_data) 3386 { 3387 /* called with tr->max_lock held */ 3388 struct track_data *track_data = tr->cond_snapshot->cond_data; 3389 struct hist_elt_data *elt_data, *track_elt_data; 3390 struct snapshot_context *context = cond_data; 3391 struct action_data *action; 3392 u64 track_val; 3393 3394 if (!track_data) 3395 return false; 3396 3397 action = track_data->action_data; 3398 3399 track_val = get_track_val(track_data->hist_data, context->elt, 3400 track_data->action_data); 3401 3402 if (!action->track_data.check_val(track_data->track_val, track_val)) 3403 return false; 3404 3405 track_data->track_val = track_val; 3406 memcpy(track_data->key, context->key, track_data->key_len); 3407 3408 elt_data = context->elt->private_data; 3409 track_elt_data = track_data->elt.private_data; 3410 if (elt_data->comm) 3411 strncpy(track_elt_data->comm, elt_data->comm, TASK_COMM_LEN); 3412 3413 track_data->updated = true; 3414 3415 return true; 3416 } 3417 3418 static void save_track_data_snapshot(struct hist_trigger_data *hist_data, 3419 struct tracing_map_elt *elt, 3420 struct trace_buffer *buffer, void *rec, 3421 struct ring_buffer_event *rbe, void *key, 3422 struct action_data *data, 3423 u64 *var_ref_vals) 3424 { 3425 struct trace_event_file *file = hist_data->event_file; 3426 struct snapshot_context context; 3427 3428 context.elt = elt; 3429 context.key = key; 3430 3431 tracing_snapshot_cond(file->tr, &context); 3432 } 3433 3434 static void hist_trigger_print_key(struct seq_file *m, 3435 struct hist_trigger_data *hist_data, 3436 void *key, 3437 struct tracing_map_elt *elt); 3438 3439 static struct action_data *snapshot_action(struct hist_trigger_data *hist_data) 3440 { 3441 unsigned int i; 3442 3443 if (!hist_data->n_actions) 3444 return NULL; 3445 3446 for (i = 0; i < hist_data->n_actions; i++) { 3447 struct action_data *data = hist_data->actions[i]; 3448 3449 if (data->action == ACTION_SNAPSHOT) 3450 return data; 3451 } 3452 3453 return NULL; 3454 } 3455 3456 static void track_data_snapshot_print(struct seq_file *m, 3457 struct hist_trigger_data *hist_data) 3458 { 3459 struct trace_event_file *file = hist_data->event_file; 3460 struct track_data *track_data; 3461 struct action_data *action; 3462 3463 track_data = tracing_cond_snapshot_data(file->tr); 3464 if (!track_data) 3465 return; 3466 3467 if (!track_data->updated) 3468 return; 3469 3470 action = snapshot_action(hist_data); 3471 if (!action) 3472 return; 3473 3474 seq_puts(m, "\nSnapshot taken (see tracing/snapshot). Details:\n"); 3475 seq_printf(m, "\ttriggering value { %s(%s) }: %10llu", 3476 action->handler == HANDLER_ONMAX ? "onmax" : "onchange", 3477 action->track_data.var_str, track_data->track_val); 3478 3479 seq_puts(m, "\ttriggered by event with key: "); 3480 hist_trigger_print_key(m, hist_data, track_data->key, &track_data->elt); 3481 seq_putc(m, '\n'); 3482 } 3483 #else 3484 static bool cond_snapshot_update(struct trace_array *tr, void *cond_data) 3485 { 3486 return false; 3487 } 3488 static void save_track_data_snapshot(struct hist_trigger_data *hist_data, 3489 struct tracing_map_elt *elt, 3490 struct trace_buffer *buffer, void *rec, 3491 struct ring_buffer_event *rbe, void *key, 3492 struct action_data *data, 3493 u64 *var_ref_vals) {} 3494 static void track_data_snapshot_print(struct seq_file *m, 3495 struct hist_trigger_data *hist_data) {} 3496 #endif /* CONFIG_TRACER_SNAPSHOT */ 3497 3498 static void track_data_print(struct seq_file *m, 3499 struct hist_trigger_data *hist_data, 3500 struct tracing_map_elt *elt, 3501 struct action_data *data) 3502 { 3503 u64 track_val = get_track_val(hist_data, elt, data); 3504 unsigned int i, save_var_idx; 3505 3506 if (data->handler == HANDLER_ONMAX) 3507 seq_printf(m, "\n\tmax: %10llu", track_val); 3508 else if (data->handler == HANDLER_ONCHANGE) 3509 seq_printf(m, "\n\tchanged: %10llu", track_val); 3510 3511 if (data->action == ACTION_SNAPSHOT) 3512 return; 3513 3514 for (i = 0; i < hist_data->n_save_vars; i++) { 3515 struct hist_field *save_val = hist_data->save_vars[i]->val; 3516 struct hist_field *save_var = hist_data->save_vars[i]->var; 3517 u64 val; 3518 3519 save_var_idx = save_var->var.idx; 3520 3521 val = tracing_map_read_var(elt, save_var_idx); 3522 3523 if (save_val->flags & HIST_FIELD_FL_STRING) { 3524 seq_printf(m, " %s: %-32s", save_var->var.name, 3525 (char *)(uintptr_t)(val)); 3526 } else 3527 seq_printf(m, " %s: %10llu", save_var->var.name, val); 3528 } 3529 } 3530 3531 static void ontrack_action(struct hist_trigger_data *hist_data, 3532 struct tracing_map_elt *elt, 3533 struct trace_buffer *buffer, void *rec, 3534 struct ring_buffer_event *rbe, void *key, 3535 struct action_data *data, u64 *var_ref_vals) 3536 { 3537 u64 var_val = var_ref_vals[data->track_data.var_ref->var_ref_idx]; 3538 3539 if (check_track_val(elt, data, var_val)) { 3540 save_track_val(hist_data, elt, data, var_val); 3541 save_track_data(hist_data, elt, buffer, rec, rbe, 3542 key, data, var_ref_vals); 3543 } 3544 } 3545 3546 static void action_data_destroy(struct action_data *data) 3547 { 3548 unsigned int i; 3549 3550 lockdep_assert_held(&event_mutex); 3551 3552 kfree(data->action_name); 3553 3554 for (i = 0; i < data->n_params; i++) 3555 kfree(data->params[i]); 3556 3557 if (data->synth_event) 3558 data->synth_event->ref--; 3559 3560 kfree(data->synth_event_name); 3561 3562 kfree(data); 3563 } 3564 3565 static void track_data_destroy(struct hist_trigger_data *hist_data, 3566 struct action_data *data) 3567 { 3568 struct trace_event_file *file = hist_data->event_file; 3569 3570 destroy_hist_field(data->track_data.track_var, 0); 3571 3572 if (data->action == ACTION_SNAPSHOT) { 3573 struct track_data *track_data; 3574 3575 track_data = tracing_cond_snapshot_data(file->tr); 3576 if (track_data && track_data->hist_data == hist_data) { 3577 tracing_snapshot_cond_disable(file->tr); 3578 track_data_free(track_data); 3579 } 3580 } 3581 3582 kfree(data->track_data.var_str); 3583 3584 action_data_destroy(data); 3585 } 3586 3587 static int action_create(struct hist_trigger_data *hist_data, 3588 struct action_data *data); 3589 3590 static int track_data_create(struct hist_trigger_data *hist_data, 3591 struct action_data *data) 3592 { 3593 struct hist_field *var_field, *ref_field, *track_var = NULL; 3594 struct trace_event_file *file = hist_data->event_file; 3595 struct trace_array *tr = file->tr; 3596 char *track_data_var_str; 3597 int ret = 0; 3598 3599 track_data_var_str = data->track_data.var_str; 3600 if (track_data_var_str[0] != '$') { 3601 hist_err(tr, HIST_ERR_ONX_NOT_VAR, errpos(track_data_var_str)); 3602 return -EINVAL; 3603 } 3604 track_data_var_str++; 3605 3606 var_field = find_target_event_var(hist_data, NULL, NULL, track_data_var_str); 3607 if (!var_field) { 3608 hist_err(tr, HIST_ERR_ONX_VAR_NOT_FOUND, errpos(track_data_var_str)); 3609 return -EINVAL; 3610 } 3611 3612 ref_field = create_var_ref(hist_data, var_field, NULL, NULL); 3613 if (!ref_field) 3614 return -ENOMEM; 3615 3616 data->track_data.var_ref = ref_field; 3617 3618 if (data->handler == HANDLER_ONMAX) 3619 track_var = create_var(hist_data, file, "__max", sizeof(u64), "u64"); 3620 if (IS_ERR(track_var)) { 3621 hist_err(tr, HIST_ERR_ONX_VAR_CREATE_FAIL, 0); 3622 ret = PTR_ERR(track_var); 3623 goto out; 3624 } 3625 3626 if (data->handler == HANDLER_ONCHANGE) 3627 track_var = create_var(hist_data, file, "__change", sizeof(u64), "u64"); 3628 if (IS_ERR(track_var)) { 3629 hist_err(tr, HIST_ERR_ONX_VAR_CREATE_FAIL, 0); 3630 ret = PTR_ERR(track_var); 3631 goto out; 3632 } 3633 data->track_data.track_var = track_var; 3634 3635 ret = action_create(hist_data, data); 3636 out: 3637 return ret; 3638 } 3639 3640 static int parse_action_params(struct trace_array *tr, char *params, 3641 struct action_data *data) 3642 { 3643 char *param, *saved_param; 3644 bool first_param = true; 3645 int ret = 0; 3646 3647 while (params) { 3648 if (data->n_params >= SYNTH_FIELDS_MAX) { 3649 hist_err(tr, HIST_ERR_TOO_MANY_PARAMS, 0); 3650 ret = -EINVAL; 3651 goto out; 3652 } 3653 3654 param = strsep(¶ms, ","); 3655 if (!param) { 3656 hist_err(tr, HIST_ERR_PARAM_NOT_FOUND, 0); 3657 ret = -EINVAL; 3658 goto out; 3659 } 3660 3661 param = strstrip(param); 3662 if (strlen(param) < 2) { 3663 hist_err(tr, HIST_ERR_INVALID_PARAM, errpos(param)); 3664 ret = -EINVAL; 3665 goto out; 3666 } 3667 3668 saved_param = kstrdup(param, GFP_KERNEL); 3669 if (!saved_param) { 3670 ret = -ENOMEM; 3671 goto out; 3672 } 3673 3674 if (first_param && data->use_trace_keyword) { 3675 data->synth_event_name = saved_param; 3676 first_param = false; 3677 continue; 3678 } 3679 first_param = false; 3680 3681 data->params[data->n_params++] = saved_param; 3682 } 3683 out: 3684 return ret; 3685 } 3686 3687 static int action_parse(struct trace_array *tr, char *str, struct action_data *data, 3688 enum handler_id handler) 3689 { 3690 char *action_name; 3691 int ret = 0; 3692 3693 strsep(&str, "."); 3694 if (!str) { 3695 hist_err(tr, HIST_ERR_ACTION_NOT_FOUND, 0); 3696 ret = -EINVAL; 3697 goto out; 3698 } 3699 3700 action_name = strsep(&str, "("); 3701 if (!action_name || !str) { 3702 hist_err(tr, HIST_ERR_ACTION_NOT_FOUND, 0); 3703 ret = -EINVAL; 3704 goto out; 3705 } 3706 3707 if (str_has_prefix(action_name, "save")) { 3708 char *params = strsep(&str, ")"); 3709 3710 if (!params) { 3711 hist_err(tr, HIST_ERR_NO_SAVE_PARAMS, 0); 3712 ret = -EINVAL; 3713 goto out; 3714 } 3715 3716 ret = parse_action_params(tr, params, data); 3717 if (ret) 3718 goto out; 3719 3720 if (handler == HANDLER_ONMAX) 3721 data->track_data.check_val = check_track_val_max; 3722 else if (handler == HANDLER_ONCHANGE) 3723 data->track_data.check_val = check_track_val_changed; 3724 else { 3725 hist_err(tr, HIST_ERR_ACTION_MISMATCH, errpos(action_name)); 3726 ret = -EINVAL; 3727 goto out; 3728 } 3729 3730 data->track_data.save_data = save_track_data_vars; 3731 data->fn = ontrack_action; 3732 data->action = ACTION_SAVE; 3733 } else if (str_has_prefix(action_name, "snapshot")) { 3734 char *params = strsep(&str, ")"); 3735 3736 if (!str) { 3737 hist_err(tr, HIST_ERR_NO_CLOSING_PAREN, errpos(params)); 3738 ret = -EINVAL; 3739 goto out; 3740 } 3741 3742 if (handler == HANDLER_ONMAX) 3743 data->track_data.check_val = check_track_val_max; 3744 else if (handler == HANDLER_ONCHANGE) 3745 data->track_data.check_val = check_track_val_changed; 3746 else { 3747 hist_err(tr, HIST_ERR_ACTION_MISMATCH, errpos(action_name)); 3748 ret = -EINVAL; 3749 goto out; 3750 } 3751 3752 data->track_data.save_data = save_track_data_snapshot; 3753 data->fn = ontrack_action; 3754 data->action = ACTION_SNAPSHOT; 3755 } else { 3756 char *params = strsep(&str, ")"); 3757 3758 if (str_has_prefix(action_name, "trace")) 3759 data->use_trace_keyword = true; 3760 3761 if (params) { 3762 ret = parse_action_params(tr, params, data); 3763 if (ret) 3764 goto out; 3765 } 3766 3767 if (handler == HANDLER_ONMAX) 3768 data->track_data.check_val = check_track_val_max; 3769 else if (handler == HANDLER_ONCHANGE) 3770 data->track_data.check_val = check_track_val_changed; 3771 3772 if (handler != HANDLER_ONMATCH) { 3773 data->track_data.save_data = action_trace; 3774 data->fn = ontrack_action; 3775 } else 3776 data->fn = action_trace; 3777 3778 data->action = ACTION_TRACE; 3779 } 3780 3781 data->action_name = kstrdup(action_name, GFP_KERNEL); 3782 if (!data->action_name) { 3783 ret = -ENOMEM; 3784 goto out; 3785 } 3786 3787 data->handler = handler; 3788 out: 3789 return ret; 3790 } 3791 3792 static struct action_data *track_data_parse(struct hist_trigger_data *hist_data, 3793 char *str, enum handler_id handler) 3794 { 3795 struct action_data *data; 3796 int ret = -EINVAL; 3797 char *var_str; 3798 3799 data = kzalloc(sizeof(*data), GFP_KERNEL); 3800 if (!data) 3801 return ERR_PTR(-ENOMEM); 3802 3803 var_str = strsep(&str, ")"); 3804 if (!var_str || !str) { 3805 ret = -EINVAL; 3806 goto free; 3807 } 3808 3809 data->track_data.var_str = kstrdup(var_str, GFP_KERNEL); 3810 if (!data->track_data.var_str) { 3811 ret = -ENOMEM; 3812 goto free; 3813 } 3814 3815 ret = action_parse(hist_data->event_file->tr, str, data, handler); 3816 if (ret) 3817 goto free; 3818 out: 3819 return data; 3820 free: 3821 track_data_destroy(hist_data, data); 3822 data = ERR_PTR(ret); 3823 goto out; 3824 } 3825 3826 static void onmatch_destroy(struct action_data *data) 3827 { 3828 kfree(data->match_data.event); 3829 kfree(data->match_data.event_system); 3830 3831 action_data_destroy(data); 3832 } 3833 3834 static void destroy_field_var(struct field_var *field_var) 3835 { 3836 if (!field_var) 3837 return; 3838 3839 destroy_hist_field(field_var->var, 0); 3840 destroy_hist_field(field_var->val, 0); 3841 3842 kfree(field_var); 3843 } 3844 3845 static void destroy_field_vars(struct hist_trigger_data *hist_data) 3846 { 3847 unsigned int i; 3848 3849 for (i = 0; i < hist_data->n_field_vars; i++) 3850 destroy_field_var(hist_data->field_vars[i]); 3851 3852 for (i = 0; i < hist_data->n_save_vars; i++) 3853 destroy_field_var(hist_data->save_vars[i]); 3854 } 3855 3856 static void save_field_var(struct hist_trigger_data *hist_data, 3857 struct field_var *field_var) 3858 { 3859 hist_data->field_vars[hist_data->n_field_vars++] = field_var; 3860 3861 /* Stack traces are saved in the string storage too */ 3862 if (field_var->val->flags & (HIST_FIELD_FL_STRING | HIST_FIELD_FL_STACKTRACE)) 3863 hist_data->n_field_var_str++; 3864 } 3865 3866 3867 static int check_synth_field(struct synth_event *event, 3868 struct hist_field *hist_field, 3869 unsigned int field_pos) 3870 { 3871 struct synth_field *field; 3872 3873 if (field_pos >= event->n_fields) 3874 return -EINVAL; 3875 3876 field = event->fields[field_pos]; 3877 3878 /* 3879 * A dynamic string synth field can accept static or 3880 * dynamic. A static string synth field can only accept a 3881 * same-sized static string, which is checked for later. 3882 */ 3883 if (strstr(hist_field->type, "char[") && field->is_string 3884 && field->is_dynamic) 3885 return 0; 3886 3887 if (strstr(hist_field->type, "long[") && field->is_stack) 3888 return 0; 3889 3890 if (strcmp(field->type, hist_field->type) != 0) { 3891 if (field->size != hist_field->size || 3892 (!field->is_string && field->is_signed != hist_field->is_signed)) 3893 return -EINVAL; 3894 } 3895 3896 return 0; 3897 } 3898 3899 static struct hist_field * 3900 trace_action_find_var(struct hist_trigger_data *hist_data, 3901 struct action_data *data, 3902 char *system, char *event, char *var) 3903 { 3904 struct trace_array *tr = hist_data->event_file->tr; 3905 struct hist_field *hist_field; 3906 3907 var++; /* skip '$' */ 3908 3909 hist_field = find_target_event_var(hist_data, system, event, var); 3910 if (!hist_field) { 3911 if (!system && data->handler == HANDLER_ONMATCH) { 3912 system = data->match_data.event_system; 3913 event = data->match_data.event; 3914 } 3915 3916 hist_field = find_event_var(hist_data, system, event, var); 3917 } 3918 3919 if (!hist_field) 3920 hist_err(tr, HIST_ERR_PARAM_NOT_FOUND, errpos(var)); 3921 3922 return hist_field; 3923 } 3924 3925 static struct hist_field * 3926 trace_action_create_field_var(struct hist_trigger_data *hist_data, 3927 struct action_data *data, char *system, 3928 char *event, char *var) 3929 { 3930 struct hist_field *hist_field = NULL; 3931 struct field_var *field_var; 3932 3933 /* 3934 * First try to create a field var on the target event (the 3935 * currently being defined). This will create a variable for 3936 * unqualified fields on the target event, or if qualified, 3937 * target fields that have qualified names matching the target. 3938 */ 3939 field_var = create_target_field_var(hist_data, system, event, var); 3940 3941 if (field_var && !IS_ERR(field_var)) { 3942 save_field_var(hist_data, field_var); 3943 hist_field = field_var->var; 3944 } else { 3945 field_var = NULL; 3946 /* 3947 * If no explicit system.event is specified, default to 3948 * looking for fields on the onmatch(system.event.xxx) 3949 * event. 3950 */ 3951 if (!system && data->handler == HANDLER_ONMATCH) { 3952 system = data->match_data.event_system; 3953 event = data->match_data.event; 3954 } 3955 3956 if (!event) 3957 goto free; 3958 /* 3959 * At this point, we're looking at a field on another 3960 * event. Because we can't modify a hist trigger on 3961 * another event to add a variable for a field, we need 3962 * to create a new trigger on that event and create the 3963 * variable at the same time. 3964 */ 3965 hist_field = create_field_var_hist(hist_data, system, event, var); 3966 if (IS_ERR(hist_field)) 3967 goto free; 3968 } 3969 out: 3970 return hist_field; 3971 free: 3972 destroy_field_var(field_var); 3973 hist_field = NULL; 3974 goto out; 3975 } 3976 3977 static int trace_action_create(struct hist_trigger_data *hist_data, 3978 struct action_data *data) 3979 { 3980 struct trace_array *tr = hist_data->event_file->tr; 3981 char *event_name, *param, *system = NULL; 3982 struct hist_field *hist_field, *var_ref; 3983 unsigned int i; 3984 unsigned int field_pos = 0; 3985 struct synth_event *event; 3986 char *synth_event_name; 3987 int var_ref_idx, ret = 0; 3988 3989 lockdep_assert_held(&event_mutex); 3990 3991 /* Sanity check to avoid out-of-bound write on 'data->var_ref_idx' */ 3992 if (data->n_params > SYNTH_FIELDS_MAX) 3993 return -EINVAL; 3994 3995 if (data->use_trace_keyword) 3996 synth_event_name = data->synth_event_name; 3997 else 3998 synth_event_name = data->action_name; 3999 4000 event = find_synth_event(synth_event_name); 4001 if (!event) { 4002 hist_err(tr, HIST_ERR_SYNTH_EVENT_NOT_FOUND, errpos(synth_event_name)); 4003 return -EINVAL; 4004 } 4005 4006 event->ref++; 4007 4008 for (i = 0; i < data->n_params; i++) { 4009 char *p; 4010 4011 p = param = kstrdup(data->params[i], GFP_KERNEL); 4012 if (!param) { 4013 ret = -ENOMEM; 4014 goto err; 4015 } 4016 4017 system = strsep(¶m, "."); 4018 if (!param) { 4019 param = (char *)system; 4020 system = event_name = NULL; 4021 } else { 4022 event_name = strsep(¶m, "."); 4023 if (!param) { 4024 kfree(p); 4025 ret = -EINVAL; 4026 goto err; 4027 } 4028 } 4029 4030 if (param[0] == '$') 4031 hist_field = trace_action_find_var(hist_data, data, 4032 system, event_name, 4033 param); 4034 else 4035 hist_field = trace_action_create_field_var(hist_data, 4036 data, 4037 system, 4038 event_name, 4039 param); 4040 4041 if (!hist_field) { 4042 kfree(p); 4043 ret = -EINVAL; 4044 goto err; 4045 } 4046 4047 if (check_synth_field(event, hist_field, field_pos) == 0) { 4048 var_ref = create_var_ref(hist_data, hist_field, 4049 system, event_name); 4050 if (!var_ref) { 4051 kfree(p); 4052 ret = -ENOMEM; 4053 goto err; 4054 } 4055 4056 var_ref_idx = find_var_ref_idx(hist_data, var_ref); 4057 if (WARN_ON(var_ref_idx < 0)) { 4058 kfree(p); 4059 ret = var_ref_idx; 4060 goto err; 4061 } 4062 4063 data->var_ref_idx[i] = var_ref_idx; 4064 4065 field_pos++; 4066 kfree(p); 4067 continue; 4068 } 4069 4070 hist_err(tr, HIST_ERR_SYNTH_TYPE_MISMATCH, errpos(param)); 4071 kfree(p); 4072 ret = -EINVAL; 4073 goto err; 4074 } 4075 4076 if (field_pos != event->n_fields) { 4077 hist_err(tr, HIST_ERR_SYNTH_COUNT_MISMATCH, errpos(event->name)); 4078 ret = -EINVAL; 4079 goto err; 4080 } 4081 4082 data->synth_event = event; 4083 out: 4084 return ret; 4085 err: 4086 event->ref--; 4087 4088 goto out; 4089 } 4090 4091 static int action_create(struct hist_trigger_data *hist_data, 4092 struct action_data *data) 4093 { 4094 struct trace_event_file *file = hist_data->event_file; 4095 struct trace_array *tr = file->tr; 4096 struct track_data *track_data; 4097 struct field_var *field_var; 4098 unsigned int i; 4099 char *param; 4100 int ret = 0; 4101 4102 if (data->action == ACTION_TRACE) 4103 return trace_action_create(hist_data, data); 4104 4105 if (data->action == ACTION_SNAPSHOT) { 4106 track_data = track_data_alloc(hist_data->key_size, data, hist_data); 4107 if (IS_ERR(track_data)) { 4108 ret = PTR_ERR(track_data); 4109 goto out; 4110 } 4111 4112 ret = tracing_snapshot_cond_enable(file->tr, track_data, 4113 cond_snapshot_update); 4114 if (ret) 4115 track_data_free(track_data); 4116 4117 goto out; 4118 } 4119 4120 if (data->action == ACTION_SAVE) { 4121 if (hist_data->n_save_vars) { 4122 ret = -EEXIST; 4123 hist_err(tr, HIST_ERR_TOO_MANY_SAVE_ACTIONS, 0); 4124 goto out; 4125 } 4126 4127 for (i = 0; i < data->n_params; i++) { 4128 param = kstrdup(data->params[i], GFP_KERNEL); 4129 if (!param) { 4130 ret = -ENOMEM; 4131 goto out; 4132 } 4133 4134 field_var = create_target_field_var(hist_data, NULL, NULL, param); 4135 if (IS_ERR(field_var)) { 4136 hist_err(tr, HIST_ERR_FIELD_VAR_CREATE_FAIL, 4137 errpos(param)); 4138 ret = PTR_ERR(field_var); 4139 kfree(param); 4140 goto out; 4141 } 4142 4143 hist_data->save_vars[hist_data->n_save_vars++] = field_var; 4144 if (field_var->val->flags & 4145 (HIST_FIELD_FL_STRING | HIST_FIELD_FL_STACKTRACE)) 4146 hist_data->n_save_var_str++; 4147 kfree(param); 4148 } 4149 } 4150 out: 4151 return ret; 4152 } 4153 4154 static int onmatch_create(struct hist_trigger_data *hist_data, 4155 struct action_data *data) 4156 { 4157 return action_create(hist_data, data); 4158 } 4159 4160 static struct action_data *onmatch_parse(struct trace_array *tr, char *str) 4161 { 4162 char *match_event, *match_event_system; 4163 struct action_data *data; 4164 int ret = -EINVAL; 4165 4166 data = kzalloc(sizeof(*data), GFP_KERNEL); 4167 if (!data) 4168 return ERR_PTR(-ENOMEM); 4169 4170 match_event = strsep(&str, ")"); 4171 if (!match_event || !str) { 4172 hist_err(tr, HIST_ERR_NO_CLOSING_PAREN, errpos(match_event)); 4173 goto free; 4174 } 4175 4176 match_event_system = strsep(&match_event, "."); 4177 if (!match_event) { 4178 hist_err(tr, HIST_ERR_SUBSYS_NOT_FOUND, errpos(match_event_system)); 4179 goto free; 4180 } 4181 4182 if (IS_ERR(event_file(tr, match_event_system, match_event))) { 4183 hist_err(tr, HIST_ERR_INVALID_SUBSYS_EVENT, errpos(match_event)); 4184 goto free; 4185 } 4186 4187 data->match_data.event = kstrdup(match_event, GFP_KERNEL); 4188 if (!data->match_data.event) { 4189 ret = -ENOMEM; 4190 goto free; 4191 } 4192 4193 data->match_data.event_system = kstrdup(match_event_system, GFP_KERNEL); 4194 if (!data->match_data.event_system) { 4195 ret = -ENOMEM; 4196 goto free; 4197 } 4198 4199 ret = action_parse(tr, str, data, HANDLER_ONMATCH); 4200 if (ret) 4201 goto free; 4202 out: 4203 return data; 4204 free: 4205 onmatch_destroy(data); 4206 data = ERR_PTR(ret); 4207 goto out; 4208 } 4209 4210 static int create_hitcount_val(struct hist_trigger_data *hist_data) 4211 { 4212 hist_data->fields[HITCOUNT_IDX] = 4213 create_hist_field(hist_data, NULL, HIST_FIELD_FL_HITCOUNT, NULL); 4214 if (!hist_data->fields[HITCOUNT_IDX]) 4215 return -ENOMEM; 4216 4217 hist_data->n_vals++; 4218 hist_data->n_fields++; 4219 4220 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX)) 4221 return -EINVAL; 4222 4223 return 0; 4224 } 4225 4226 static int __create_val_field(struct hist_trigger_data *hist_data, 4227 unsigned int val_idx, 4228 struct trace_event_file *file, 4229 char *var_name, char *field_str, 4230 unsigned long flags) 4231 { 4232 struct hist_field *hist_field; 4233 int ret = 0, n_subexprs = 0; 4234 4235 hist_field = parse_expr(hist_data, file, field_str, flags, var_name, &n_subexprs); 4236 if (IS_ERR(hist_field)) { 4237 ret = PTR_ERR(hist_field); 4238 goto out; 4239 } 4240 4241 /* Some types cannot be a value */ 4242 if (hist_field->flags & (HIST_FIELD_FL_GRAPH | HIST_FIELD_FL_PERCENT | 4243 HIST_FIELD_FL_BUCKET | HIST_FIELD_FL_LOG2 | 4244 HIST_FIELD_FL_SYM | HIST_FIELD_FL_SYM_OFFSET | 4245 HIST_FIELD_FL_SYSCALL | HIST_FIELD_FL_STACKTRACE)) { 4246 hist_err(file->tr, HIST_ERR_BAD_FIELD_MODIFIER, errpos(field_str)); 4247 ret = -EINVAL; 4248 } 4249 4250 hist_data->fields[val_idx] = hist_field; 4251 4252 ++hist_data->n_vals; 4253 ++hist_data->n_fields; 4254 4255 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX)) 4256 ret = -EINVAL; 4257 out: 4258 return ret; 4259 } 4260 4261 static int create_val_field(struct hist_trigger_data *hist_data, 4262 unsigned int val_idx, 4263 struct trace_event_file *file, 4264 char *field_str) 4265 { 4266 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX)) 4267 return -EINVAL; 4268 4269 return __create_val_field(hist_data, val_idx, file, NULL, field_str, 0); 4270 } 4271 4272 static const char no_comm[] = "(no comm)"; 4273 4274 static u64 hist_field_execname(struct hist_field *hist_field, 4275 struct tracing_map_elt *elt, 4276 struct trace_buffer *buffer, 4277 struct ring_buffer_event *rbe, 4278 void *event) 4279 { 4280 struct hist_elt_data *elt_data; 4281 4282 if (WARN_ON_ONCE(!elt)) 4283 return (u64)(unsigned long)no_comm; 4284 4285 elt_data = elt->private_data; 4286 4287 if (WARN_ON_ONCE(!elt_data->comm)) 4288 return (u64)(unsigned long)no_comm; 4289 4290 return (u64)(unsigned long)(elt_data->comm); 4291 } 4292 4293 static u64 hist_field_stack(struct hist_field *hist_field, 4294 struct tracing_map_elt *elt, 4295 struct trace_buffer *buffer, 4296 struct ring_buffer_event *rbe, 4297 void *event) 4298 { 4299 u32 str_item = *(u32 *)(event + hist_field->field->offset); 4300 int str_loc = str_item & 0xffff; 4301 char *addr = (char *)(event + str_loc); 4302 4303 return (u64)(unsigned long)addr; 4304 } 4305 4306 static u64 hist_fn_call(struct hist_field *hist_field, 4307 struct tracing_map_elt *elt, 4308 struct trace_buffer *buffer, 4309 struct ring_buffer_event *rbe, 4310 void *event) 4311 { 4312 switch (hist_field->fn_num) { 4313 case HIST_FIELD_FN_VAR_REF: 4314 return hist_field_var_ref(hist_field, elt, buffer, rbe, event); 4315 case HIST_FIELD_FN_COUNTER: 4316 return hist_field_counter(hist_field, elt, buffer, rbe, event); 4317 case HIST_FIELD_FN_CONST: 4318 return hist_field_const(hist_field, elt, buffer, rbe, event); 4319 case HIST_FIELD_FN_LOG2: 4320 return hist_field_log2(hist_field, elt, buffer, rbe, event); 4321 case HIST_FIELD_FN_BUCKET: 4322 return hist_field_bucket(hist_field, elt, buffer, rbe, event); 4323 case HIST_FIELD_FN_TIMESTAMP: 4324 return hist_field_timestamp(hist_field, elt, buffer, rbe, event); 4325 case HIST_FIELD_FN_CPU: 4326 return hist_field_cpu(hist_field, elt, buffer, rbe, event); 4327 case HIST_FIELD_FN_STRING: 4328 return hist_field_string(hist_field, elt, buffer, rbe, event); 4329 case HIST_FIELD_FN_DYNSTRING: 4330 return hist_field_dynstring(hist_field, elt, buffer, rbe, event); 4331 case HIST_FIELD_FN_RELDYNSTRING: 4332 return hist_field_reldynstring(hist_field, elt, buffer, rbe, event); 4333 case HIST_FIELD_FN_PSTRING: 4334 return hist_field_pstring(hist_field, elt, buffer, rbe, event); 4335 case HIST_FIELD_FN_S64: 4336 return hist_field_s64(hist_field, elt, buffer, rbe, event); 4337 case HIST_FIELD_FN_U64: 4338 return hist_field_u64(hist_field, elt, buffer, rbe, event); 4339 case HIST_FIELD_FN_S32: 4340 return hist_field_s32(hist_field, elt, buffer, rbe, event); 4341 case HIST_FIELD_FN_U32: 4342 return hist_field_u32(hist_field, elt, buffer, rbe, event); 4343 case HIST_FIELD_FN_S16: 4344 return hist_field_s16(hist_field, elt, buffer, rbe, event); 4345 case HIST_FIELD_FN_U16: 4346 return hist_field_u16(hist_field, elt, buffer, rbe, event); 4347 case HIST_FIELD_FN_S8: 4348 return hist_field_s8(hist_field, elt, buffer, rbe, event); 4349 case HIST_FIELD_FN_U8: 4350 return hist_field_u8(hist_field, elt, buffer, rbe, event); 4351 case HIST_FIELD_FN_UMINUS: 4352 return hist_field_unary_minus(hist_field, elt, buffer, rbe, event); 4353 case HIST_FIELD_FN_MINUS: 4354 return hist_field_minus(hist_field, elt, buffer, rbe, event); 4355 case HIST_FIELD_FN_PLUS: 4356 return hist_field_plus(hist_field, elt, buffer, rbe, event); 4357 case HIST_FIELD_FN_DIV: 4358 return hist_field_div(hist_field, elt, buffer, rbe, event); 4359 case HIST_FIELD_FN_MULT: 4360 return hist_field_mult(hist_field, elt, buffer, rbe, event); 4361 case HIST_FIELD_FN_DIV_POWER2: 4362 return div_by_power_of_two(hist_field, elt, buffer, rbe, event); 4363 case HIST_FIELD_FN_DIV_NOT_POWER2: 4364 return div_by_not_power_of_two(hist_field, elt, buffer, rbe, event); 4365 case HIST_FIELD_FN_DIV_MULT_SHIFT: 4366 return div_by_mult_and_shift(hist_field, elt, buffer, rbe, event); 4367 case HIST_FIELD_FN_EXECNAME: 4368 return hist_field_execname(hist_field, elt, buffer, rbe, event); 4369 case HIST_FIELD_FN_STACK: 4370 return hist_field_stack(hist_field, elt, buffer, rbe, event); 4371 default: 4372 return 0; 4373 } 4374 } 4375 4376 /* Convert a var that points to common_pid.execname to a string */ 4377 static void update_var_execname(struct hist_field *hist_field) 4378 { 4379 hist_field->flags = HIST_FIELD_FL_STRING | HIST_FIELD_FL_VAR | 4380 HIST_FIELD_FL_EXECNAME; 4381 hist_field->size = MAX_FILTER_STR_VAL; 4382 hist_field->is_signed = 0; 4383 4384 kfree_const(hist_field->type); 4385 hist_field->type = "char[]"; 4386 4387 hist_field->fn_num = HIST_FIELD_FN_EXECNAME; 4388 } 4389 4390 static int create_var_field(struct hist_trigger_data *hist_data, 4391 unsigned int val_idx, 4392 struct trace_event_file *file, 4393 char *var_name, char *expr_str) 4394 { 4395 struct trace_array *tr = hist_data->event_file->tr; 4396 unsigned long flags = 0; 4397 int ret; 4398 4399 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX)) 4400 return -EINVAL; 4401 4402 if (find_var(hist_data, file, var_name) && !hist_data->remove) { 4403 hist_err(tr, HIST_ERR_DUPLICATE_VAR, errpos(var_name)); 4404 return -EINVAL; 4405 } 4406 4407 flags |= HIST_FIELD_FL_VAR; 4408 hist_data->n_vars++; 4409 if (WARN_ON(hist_data->n_vars > TRACING_MAP_VARS_MAX)) 4410 return -EINVAL; 4411 4412 ret = __create_val_field(hist_data, val_idx, file, var_name, expr_str, flags); 4413 4414 if (!ret && hist_data->fields[val_idx]->flags & HIST_FIELD_FL_EXECNAME) 4415 update_var_execname(hist_data->fields[val_idx]); 4416 4417 if (!ret && hist_data->fields[val_idx]->flags & 4418 (HIST_FIELD_FL_STRING | HIST_FIELD_FL_STACKTRACE)) 4419 hist_data->fields[val_idx]->var_str_idx = hist_data->n_var_str++; 4420 4421 return ret; 4422 } 4423 4424 static int create_val_fields(struct hist_trigger_data *hist_data, 4425 struct trace_event_file *file) 4426 { 4427 unsigned int i, j = 1, n_hitcount = 0; 4428 char *fields_str, *field_str; 4429 int ret; 4430 4431 ret = create_hitcount_val(hist_data); 4432 if (ret) 4433 goto out; 4434 4435 fields_str = hist_data->attrs->vals_str; 4436 if (!fields_str) 4437 goto out; 4438 4439 for (i = 0, j = 1; i < TRACING_MAP_VALS_MAX && 4440 j < TRACING_MAP_VALS_MAX; i++) { 4441 field_str = strsep(&fields_str, ","); 4442 if (!field_str) 4443 break; 4444 4445 if (strcmp(field_str, "hitcount") == 0) { 4446 if (!n_hitcount++) 4447 continue; 4448 } 4449 4450 ret = create_val_field(hist_data, j++, file, field_str); 4451 if (ret) 4452 goto out; 4453 } 4454 4455 if (fields_str && (strcmp(fields_str, "hitcount") != 0)) 4456 ret = -EINVAL; 4457 out: 4458 /* There is only raw hitcount but nohitcount suppresses it. */ 4459 if (j == 1 && hist_data->attrs->no_hitcount) { 4460 hist_err(hist_data->event_file->tr, HIST_ERR_NEED_NOHC_VAL, 0); 4461 ret = -ENOENT; 4462 } 4463 4464 return ret; 4465 } 4466 4467 static int create_key_field(struct hist_trigger_data *hist_data, 4468 unsigned int key_idx, 4469 unsigned int key_offset, 4470 struct trace_event_file *file, 4471 char *field_str) 4472 { 4473 struct trace_array *tr = hist_data->event_file->tr; 4474 struct hist_field *hist_field = NULL; 4475 unsigned long flags = 0; 4476 unsigned int key_size; 4477 int ret = 0, n_subexprs = 0; 4478 4479 if (WARN_ON(key_idx >= HIST_FIELDS_MAX)) 4480 return -EINVAL; 4481 4482 flags |= HIST_FIELD_FL_KEY; 4483 4484 if (strcmp(field_str, "stacktrace") == 0) { 4485 flags |= HIST_FIELD_FL_STACKTRACE; 4486 key_size = sizeof(unsigned long) * HIST_STACKTRACE_DEPTH; 4487 hist_field = create_hist_field(hist_data, NULL, flags, NULL); 4488 } else { 4489 hist_field = parse_expr(hist_data, file, field_str, flags, 4490 NULL, &n_subexprs); 4491 if (IS_ERR(hist_field)) { 4492 ret = PTR_ERR(hist_field); 4493 goto out; 4494 } 4495 4496 if (field_has_hist_vars(hist_field, 0)) { 4497 hist_err(tr, HIST_ERR_INVALID_REF_KEY, errpos(field_str)); 4498 destroy_hist_field(hist_field, 0); 4499 ret = -EINVAL; 4500 goto out; 4501 } 4502 4503 key_size = hist_field->size; 4504 } 4505 4506 hist_data->fields[key_idx] = hist_field; 4507 4508 key_size = ALIGN(key_size, sizeof(u64)); 4509 hist_data->fields[key_idx]->size = key_size; 4510 hist_data->fields[key_idx]->offset = key_offset; 4511 4512 hist_data->key_size += key_size; 4513 4514 if (hist_data->key_size > HIST_KEY_SIZE_MAX) { 4515 ret = -EINVAL; 4516 goto out; 4517 } 4518 4519 hist_data->n_keys++; 4520 hist_data->n_fields++; 4521 4522 if (WARN_ON(hist_data->n_keys > TRACING_MAP_KEYS_MAX)) 4523 return -EINVAL; 4524 4525 ret = key_size; 4526 out: 4527 return ret; 4528 } 4529 4530 static int create_key_fields(struct hist_trigger_data *hist_data, 4531 struct trace_event_file *file) 4532 { 4533 unsigned int i, key_offset = 0, n_vals = hist_data->n_vals; 4534 char *fields_str, *field_str; 4535 int ret = -EINVAL; 4536 4537 fields_str = hist_data->attrs->keys_str; 4538 if (!fields_str) 4539 goto out; 4540 4541 for (i = n_vals; i < n_vals + TRACING_MAP_KEYS_MAX; i++) { 4542 field_str = strsep(&fields_str, ","); 4543 if (!field_str) 4544 break; 4545 ret = create_key_field(hist_data, i, key_offset, 4546 file, field_str); 4547 if (ret < 0) 4548 goto out; 4549 key_offset += ret; 4550 } 4551 if (fields_str) { 4552 ret = -EINVAL; 4553 goto out; 4554 } 4555 ret = 0; 4556 out: 4557 return ret; 4558 } 4559 4560 static int create_var_fields(struct hist_trigger_data *hist_data, 4561 struct trace_event_file *file) 4562 { 4563 unsigned int i, j = hist_data->n_vals; 4564 int ret = 0; 4565 4566 unsigned int n_vars = hist_data->attrs->var_defs.n_vars; 4567 4568 for (i = 0; i < n_vars; i++) { 4569 char *var_name = hist_data->attrs->var_defs.name[i]; 4570 char *expr = hist_data->attrs->var_defs.expr[i]; 4571 4572 ret = create_var_field(hist_data, j++, file, var_name, expr); 4573 if (ret) 4574 goto out; 4575 } 4576 out: 4577 return ret; 4578 } 4579 4580 static void free_var_defs(struct hist_trigger_data *hist_data) 4581 { 4582 unsigned int i; 4583 4584 for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) { 4585 kfree(hist_data->attrs->var_defs.name[i]); 4586 kfree(hist_data->attrs->var_defs.expr[i]); 4587 } 4588 4589 hist_data->attrs->var_defs.n_vars = 0; 4590 } 4591 4592 static int parse_var_defs(struct hist_trigger_data *hist_data) 4593 { 4594 struct trace_array *tr = hist_data->event_file->tr; 4595 char *s, *str, *var_name, *field_str; 4596 unsigned int i, j, n_vars = 0; 4597 int ret = 0; 4598 4599 for (i = 0; i < hist_data->attrs->n_assignments; i++) { 4600 str = hist_data->attrs->assignment_str[i]; 4601 for (j = 0; j < TRACING_MAP_VARS_MAX; j++) { 4602 field_str = strsep(&str, ","); 4603 if (!field_str) 4604 break; 4605 4606 var_name = strsep(&field_str, "="); 4607 if (!var_name || !field_str) { 4608 hist_err(tr, HIST_ERR_MALFORMED_ASSIGNMENT, 4609 errpos(var_name)); 4610 ret = -EINVAL; 4611 goto free; 4612 } 4613 4614 if (n_vars == TRACING_MAP_VARS_MAX) { 4615 hist_err(tr, HIST_ERR_TOO_MANY_VARS, errpos(var_name)); 4616 ret = -EINVAL; 4617 goto free; 4618 } 4619 4620 s = kstrdup(var_name, GFP_KERNEL); 4621 if (!s) { 4622 ret = -ENOMEM; 4623 goto free; 4624 } 4625 hist_data->attrs->var_defs.name[n_vars] = s; 4626 4627 s = kstrdup(field_str, GFP_KERNEL); 4628 if (!s) { 4629 kfree(hist_data->attrs->var_defs.name[n_vars]); 4630 hist_data->attrs->var_defs.name[n_vars] = NULL; 4631 ret = -ENOMEM; 4632 goto free; 4633 } 4634 hist_data->attrs->var_defs.expr[n_vars++] = s; 4635 4636 hist_data->attrs->var_defs.n_vars = n_vars; 4637 } 4638 } 4639 4640 return ret; 4641 free: 4642 free_var_defs(hist_data); 4643 4644 return ret; 4645 } 4646 4647 static int create_hist_fields(struct hist_trigger_data *hist_data, 4648 struct trace_event_file *file) 4649 { 4650 int ret; 4651 4652 ret = parse_var_defs(hist_data); 4653 if (ret) 4654 return ret; 4655 4656 ret = create_val_fields(hist_data, file); 4657 if (ret) 4658 goto out; 4659 4660 ret = create_var_fields(hist_data, file); 4661 if (ret) 4662 goto out; 4663 4664 ret = create_key_fields(hist_data, file); 4665 4666 out: 4667 free_var_defs(hist_data); 4668 4669 return ret; 4670 } 4671 4672 static int is_descending(struct trace_array *tr, const char *str) 4673 { 4674 if (!str) 4675 return 0; 4676 4677 if (strcmp(str, "descending") == 0) 4678 return 1; 4679 4680 if (strcmp(str, "ascending") == 0) 4681 return 0; 4682 4683 hist_err(tr, HIST_ERR_INVALID_SORT_MODIFIER, errpos((char *)str)); 4684 4685 return -EINVAL; 4686 } 4687 4688 static int create_sort_keys(struct hist_trigger_data *hist_data) 4689 { 4690 struct trace_array *tr = hist_data->event_file->tr; 4691 char *fields_str = hist_data->attrs->sort_key_str; 4692 struct tracing_map_sort_key *sort_key; 4693 int descending, ret = 0; 4694 unsigned int i, j, k; 4695 4696 hist_data->n_sort_keys = 1; /* we always have at least one, hitcount */ 4697 4698 if (!fields_str) 4699 goto out; 4700 4701 for (i = 0; i < TRACING_MAP_SORT_KEYS_MAX; i++) { 4702 struct hist_field *hist_field; 4703 char *field_str, *field_name; 4704 const char *test_name; 4705 4706 sort_key = &hist_data->sort_keys[i]; 4707 4708 field_str = strsep(&fields_str, ","); 4709 if (!field_str) 4710 break; 4711 4712 if (!*field_str) { 4713 ret = -EINVAL; 4714 hist_err(tr, HIST_ERR_EMPTY_SORT_FIELD, errpos("sort=")); 4715 break; 4716 } 4717 4718 if ((i == TRACING_MAP_SORT_KEYS_MAX - 1) && fields_str) { 4719 hist_err(tr, HIST_ERR_TOO_MANY_SORT_FIELDS, errpos("sort=")); 4720 ret = -EINVAL; 4721 break; 4722 } 4723 4724 field_name = strsep(&field_str, "."); 4725 if (!field_name || !*field_name) { 4726 ret = -EINVAL; 4727 hist_err(tr, HIST_ERR_EMPTY_SORT_FIELD, errpos("sort=")); 4728 break; 4729 } 4730 4731 if (strcmp(field_name, "hitcount") == 0) { 4732 descending = is_descending(tr, field_str); 4733 if (descending < 0) { 4734 ret = descending; 4735 break; 4736 } 4737 sort_key->descending = descending; 4738 continue; 4739 } 4740 4741 for (j = 1, k = 1; j < hist_data->n_fields; j++) { 4742 unsigned int idx; 4743 4744 hist_field = hist_data->fields[j]; 4745 if (hist_field->flags & HIST_FIELD_FL_VAR) 4746 continue; 4747 4748 idx = k++; 4749 4750 test_name = hist_field_name(hist_field, 0); 4751 4752 if (strcmp(field_name, test_name) == 0) { 4753 sort_key->field_idx = idx; 4754 descending = is_descending(tr, field_str); 4755 if (descending < 0) { 4756 ret = descending; 4757 goto out; 4758 } 4759 sort_key->descending = descending; 4760 break; 4761 } 4762 } 4763 if (j == hist_data->n_fields) { 4764 ret = -EINVAL; 4765 hist_err(tr, HIST_ERR_INVALID_SORT_FIELD, errpos(field_name)); 4766 break; 4767 } 4768 } 4769 4770 hist_data->n_sort_keys = i; 4771 out: 4772 return ret; 4773 } 4774 4775 static void destroy_actions(struct hist_trigger_data *hist_data) 4776 { 4777 unsigned int i; 4778 4779 for (i = 0; i < hist_data->n_actions; i++) { 4780 struct action_data *data = hist_data->actions[i]; 4781 4782 if (data->handler == HANDLER_ONMATCH) 4783 onmatch_destroy(data); 4784 else if (data->handler == HANDLER_ONMAX || 4785 data->handler == HANDLER_ONCHANGE) 4786 track_data_destroy(hist_data, data); 4787 else 4788 kfree(data); 4789 } 4790 } 4791 4792 static int parse_actions(struct hist_trigger_data *hist_data) 4793 { 4794 struct trace_array *tr = hist_data->event_file->tr; 4795 struct action_data *data; 4796 unsigned int i; 4797 int ret = 0; 4798 char *str; 4799 int len; 4800 4801 for (i = 0; i < hist_data->attrs->n_actions; i++) { 4802 str = hist_data->attrs->action_str[i]; 4803 4804 if ((len = str_has_prefix(str, "onmatch("))) { 4805 char *action_str = str + len; 4806 4807 data = onmatch_parse(tr, action_str); 4808 if (IS_ERR(data)) { 4809 ret = PTR_ERR(data); 4810 break; 4811 } 4812 } else if ((len = str_has_prefix(str, "onmax("))) { 4813 char *action_str = str + len; 4814 4815 data = track_data_parse(hist_data, action_str, 4816 HANDLER_ONMAX); 4817 if (IS_ERR(data)) { 4818 ret = PTR_ERR(data); 4819 break; 4820 } 4821 } else if ((len = str_has_prefix(str, "onchange("))) { 4822 char *action_str = str + len; 4823 4824 data = track_data_parse(hist_data, action_str, 4825 HANDLER_ONCHANGE); 4826 if (IS_ERR(data)) { 4827 ret = PTR_ERR(data); 4828 break; 4829 } 4830 } else { 4831 ret = -EINVAL; 4832 break; 4833 } 4834 4835 hist_data->actions[hist_data->n_actions++] = data; 4836 } 4837 4838 return ret; 4839 } 4840 4841 static int create_actions(struct hist_trigger_data *hist_data) 4842 { 4843 struct action_data *data; 4844 unsigned int i; 4845 int ret = 0; 4846 4847 for (i = 0; i < hist_data->attrs->n_actions; i++) { 4848 data = hist_data->actions[i]; 4849 4850 if (data->handler == HANDLER_ONMATCH) { 4851 ret = onmatch_create(hist_data, data); 4852 if (ret) 4853 break; 4854 } else if (data->handler == HANDLER_ONMAX || 4855 data->handler == HANDLER_ONCHANGE) { 4856 ret = track_data_create(hist_data, data); 4857 if (ret) 4858 break; 4859 } else { 4860 ret = -EINVAL; 4861 break; 4862 } 4863 } 4864 4865 return ret; 4866 } 4867 4868 static void print_actions(struct seq_file *m, 4869 struct hist_trigger_data *hist_data, 4870 struct tracing_map_elt *elt) 4871 { 4872 unsigned int i; 4873 4874 for (i = 0; i < hist_data->n_actions; i++) { 4875 struct action_data *data = hist_data->actions[i]; 4876 4877 if (data->action == ACTION_SNAPSHOT) 4878 continue; 4879 4880 if (data->handler == HANDLER_ONMAX || 4881 data->handler == HANDLER_ONCHANGE) 4882 track_data_print(m, hist_data, elt, data); 4883 } 4884 } 4885 4886 static void print_action_spec(struct seq_file *m, 4887 struct hist_trigger_data *hist_data, 4888 struct action_data *data) 4889 { 4890 unsigned int i; 4891 4892 if (data->action == ACTION_SAVE) { 4893 for (i = 0; i < hist_data->n_save_vars; i++) { 4894 seq_printf(m, "%s", hist_data->save_vars[i]->var->var.name); 4895 if (i < hist_data->n_save_vars - 1) 4896 seq_puts(m, ","); 4897 } 4898 } else if (data->action == ACTION_TRACE) { 4899 if (data->use_trace_keyword) 4900 seq_printf(m, "%s", data->synth_event_name); 4901 for (i = 0; i < data->n_params; i++) { 4902 if (i || data->use_trace_keyword) 4903 seq_puts(m, ","); 4904 seq_printf(m, "%s", data->params[i]); 4905 } 4906 } 4907 } 4908 4909 static void print_track_data_spec(struct seq_file *m, 4910 struct hist_trigger_data *hist_data, 4911 struct action_data *data) 4912 { 4913 if (data->handler == HANDLER_ONMAX) 4914 seq_puts(m, ":onmax("); 4915 else if (data->handler == HANDLER_ONCHANGE) 4916 seq_puts(m, ":onchange("); 4917 seq_printf(m, "%s", data->track_data.var_str); 4918 seq_printf(m, ").%s(", data->action_name); 4919 4920 print_action_spec(m, hist_data, data); 4921 4922 seq_puts(m, ")"); 4923 } 4924 4925 static void print_onmatch_spec(struct seq_file *m, 4926 struct hist_trigger_data *hist_data, 4927 struct action_data *data) 4928 { 4929 seq_printf(m, ":onmatch(%s.%s).", data->match_data.event_system, 4930 data->match_data.event); 4931 4932 seq_printf(m, "%s(", data->action_name); 4933 4934 print_action_spec(m, hist_data, data); 4935 4936 seq_puts(m, ")"); 4937 } 4938 4939 static bool actions_match(struct hist_trigger_data *hist_data, 4940 struct hist_trigger_data *hist_data_test) 4941 { 4942 unsigned int i, j; 4943 4944 if (hist_data->n_actions != hist_data_test->n_actions) 4945 return false; 4946 4947 for (i = 0; i < hist_data->n_actions; i++) { 4948 struct action_data *data = hist_data->actions[i]; 4949 struct action_data *data_test = hist_data_test->actions[i]; 4950 char *action_name, *action_name_test; 4951 4952 if (data->handler != data_test->handler) 4953 return false; 4954 if (data->action != data_test->action) 4955 return false; 4956 4957 if (data->n_params != data_test->n_params) 4958 return false; 4959 4960 for (j = 0; j < data->n_params; j++) { 4961 if (strcmp(data->params[j], data_test->params[j]) != 0) 4962 return false; 4963 } 4964 4965 if (data->use_trace_keyword) 4966 action_name = data->synth_event_name; 4967 else 4968 action_name = data->action_name; 4969 4970 if (data_test->use_trace_keyword) 4971 action_name_test = data_test->synth_event_name; 4972 else 4973 action_name_test = data_test->action_name; 4974 4975 if (strcmp(action_name, action_name_test) != 0) 4976 return false; 4977 4978 if (data->handler == HANDLER_ONMATCH) { 4979 if (strcmp(data->match_data.event_system, 4980 data_test->match_data.event_system) != 0) 4981 return false; 4982 if (strcmp(data->match_data.event, 4983 data_test->match_data.event) != 0) 4984 return false; 4985 } else if (data->handler == HANDLER_ONMAX || 4986 data->handler == HANDLER_ONCHANGE) { 4987 if (strcmp(data->track_data.var_str, 4988 data_test->track_data.var_str) != 0) 4989 return false; 4990 } 4991 } 4992 4993 return true; 4994 } 4995 4996 4997 static void print_actions_spec(struct seq_file *m, 4998 struct hist_trigger_data *hist_data) 4999 { 5000 unsigned int i; 5001 5002 for (i = 0; i < hist_data->n_actions; i++) { 5003 struct action_data *data = hist_data->actions[i]; 5004 5005 if (data->handler == HANDLER_ONMATCH) 5006 print_onmatch_spec(m, hist_data, data); 5007 else if (data->handler == HANDLER_ONMAX || 5008 data->handler == HANDLER_ONCHANGE) 5009 print_track_data_spec(m, hist_data, data); 5010 } 5011 } 5012 5013 static void destroy_field_var_hists(struct hist_trigger_data *hist_data) 5014 { 5015 unsigned int i; 5016 5017 for (i = 0; i < hist_data->n_field_var_hists; i++) { 5018 kfree(hist_data->field_var_hists[i]->cmd); 5019 kfree(hist_data->field_var_hists[i]); 5020 } 5021 } 5022 5023 static void destroy_hist_data(struct hist_trigger_data *hist_data) 5024 { 5025 if (!hist_data) 5026 return; 5027 5028 destroy_hist_trigger_attrs(hist_data->attrs); 5029 destroy_hist_fields(hist_data); 5030 tracing_map_destroy(hist_data->map); 5031 5032 destroy_actions(hist_data); 5033 destroy_field_vars(hist_data); 5034 destroy_field_var_hists(hist_data); 5035 5036 kfree(hist_data); 5037 } 5038 5039 static int create_tracing_map_fields(struct hist_trigger_data *hist_data) 5040 { 5041 struct tracing_map *map = hist_data->map; 5042 struct ftrace_event_field *field; 5043 struct hist_field *hist_field; 5044 int i, idx = 0; 5045 5046 for_each_hist_field(i, hist_data) { 5047 hist_field = hist_data->fields[i]; 5048 if (hist_field->flags & HIST_FIELD_FL_KEY) { 5049 tracing_map_cmp_fn_t cmp_fn; 5050 5051 field = hist_field->field; 5052 5053 if (hist_field->flags & HIST_FIELD_FL_STACKTRACE) 5054 cmp_fn = tracing_map_cmp_none; 5055 else if (!field || hist_field->flags & HIST_FIELD_FL_CPU) 5056 cmp_fn = tracing_map_cmp_num(hist_field->size, 5057 hist_field->is_signed); 5058 else if (is_string_field(field)) 5059 cmp_fn = tracing_map_cmp_string; 5060 else 5061 cmp_fn = tracing_map_cmp_num(field->size, 5062 field->is_signed); 5063 idx = tracing_map_add_key_field(map, 5064 hist_field->offset, 5065 cmp_fn); 5066 } else if (!(hist_field->flags & HIST_FIELD_FL_VAR)) 5067 idx = tracing_map_add_sum_field(map); 5068 5069 if (idx < 0) 5070 return idx; 5071 5072 if (hist_field->flags & HIST_FIELD_FL_VAR) { 5073 idx = tracing_map_add_var(map); 5074 if (idx < 0) 5075 return idx; 5076 hist_field->var.idx = idx; 5077 hist_field->var.hist_data = hist_data; 5078 } 5079 } 5080 5081 return 0; 5082 } 5083 5084 static struct hist_trigger_data * 5085 create_hist_data(unsigned int map_bits, 5086 struct hist_trigger_attrs *attrs, 5087 struct trace_event_file *file, 5088 bool remove) 5089 { 5090 const struct tracing_map_ops *map_ops = NULL; 5091 struct hist_trigger_data *hist_data; 5092 int ret = 0; 5093 5094 hist_data = kzalloc(sizeof(*hist_data), GFP_KERNEL); 5095 if (!hist_data) 5096 return ERR_PTR(-ENOMEM); 5097 5098 hist_data->attrs = attrs; 5099 hist_data->remove = remove; 5100 hist_data->event_file = file; 5101 5102 ret = parse_actions(hist_data); 5103 if (ret) 5104 goto free; 5105 5106 ret = create_hist_fields(hist_data, file); 5107 if (ret) 5108 goto free; 5109 5110 ret = create_sort_keys(hist_data); 5111 if (ret) 5112 goto free; 5113 5114 map_ops = &hist_trigger_elt_data_ops; 5115 5116 hist_data->map = tracing_map_create(map_bits, hist_data->key_size, 5117 map_ops, hist_data); 5118 if (IS_ERR(hist_data->map)) { 5119 ret = PTR_ERR(hist_data->map); 5120 hist_data->map = NULL; 5121 goto free; 5122 } 5123 5124 ret = create_tracing_map_fields(hist_data); 5125 if (ret) 5126 goto free; 5127 out: 5128 return hist_data; 5129 free: 5130 hist_data->attrs = NULL; 5131 5132 destroy_hist_data(hist_data); 5133 5134 hist_data = ERR_PTR(ret); 5135 5136 goto out; 5137 } 5138 5139 static void hist_trigger_elt_update(struct hist_trigger_data *hist_data, 5140 struct tracing_map_elt *elt, 5141 struct trace_buffer *buffer, void *rec, 5142 struct ring_buffer_event *rbe, 5143 u64 *var_ref_vals) 5144 { 5145 struct hist_elt_data *elt_data; 5146 struct hist_field *hist_field; 5147 unsigned int i, var_idx; 5148 u64 hist_val; 5149 5150 elt_data = elt->private_data; 5151 elt_data->var_ref_vals = var_ref_vals; 5152 5153 for_each_hist_val_field(i, hist_data) { 5154 hist_field = hist_data->fields[i]; 5155 hist_val = hist_fn_call(hist_field, elt, buffer, rbe, rec); 5156 if (hist_field->flags & HIST_FIELD_FL_VAR) { 5157 var_idx = hist_field->var.idx; 5158 5159 if (hist_field->flags & 5160 (HIST_FIELD_FL_STRING | HIST_FIELD_FL_STACKTRACE)) { 5161 unsigned int str_start, var_str_idx, idx; 5162 char *str, *val_str; 5163 unsigned int size; 5164 5165 str_start = hist_data->n_field_var_str + 5166 hist_data->n_save_var_str; 5167 var_str_idx = hist_field->var_str_idx; 5168 idx = str_start + var_str_idx; 5169 5170 str = elt_data->field_var_str[idx]; 5171 val_str = (char *)(uintptr_t)hist_val; 5172 5173 if (hist_field->flags & HIST_FIELD_FL_STRING) { 5174 size = min(hist_field->size, STR_VAR_LEN_MAX); 5175 strscpy(str, val_str, size); 5176 } else { 5177 char *stack_start = str + sizeof(unsigned long); 5178 int e; 5179 5180 e = stack_trace_save((void *)stack_start, 5181 HIST_STACKTRACE_DEPTH, 5182 HIST_STACKTRACE_SKIP); 5183 if (e < HIST_STACKTRACE_DEPTH - 1) 5184 ((unsigned long *)stack_start)[e] = 0; 5185 *((unsigned long *)str) = e; 5186 } 5187 hist_val = (u64)(uintptr_t)str; 5188 } 5189 tracing_map_set_var(elt, var_idx, hist_val); 5190 continue; 5191 } 5192 tracing_map_update_sum(elt, i, hist_val); 5193 } 5194 5195 for_each_hist_key_field(i, hist_data) { 5196 hist_field = hist_data->fields[i]; 5197 if (hist_field->flags & HIST_FIELD_FL_VAR) { 5198 hist_val = hist_fn_call(hist_field, elt, buffer, rbe, rec); 5199 var_idx = hist_field->var.idx; 5200 tracing_map_set_var(elt, var_idx, hist_val); 5201 } 5202 } 5203 5204 update_field_vars(hist_data, elt, buffer, rbe, rec); 5205 } 5206 5207 static inline void add_to_key(char *compound_key, void *key, 5208 struct hist_field *key_field, void *rec) 5209 { 5210 size_t size = key_field->size; 5211 5212 if (key_field->flags & HIST_FIELD_FL_STRING) { 5213 struct ftrace_event_field *field; 5214 5215 field = key_field->field; 5216 if (field->filter_type == FILTER_DYN_STRING || 5217 field->filter_type == FILTER_RDYN_STRING) 5218 size = *(u32 *)(rec + field->offset) >> 16; 5219 else if (field->filter_type == FILTER_STATIC_STRING) 5220 size = field->size; 5221 5222 /* ensure NULL-termination */ 5223 if (size > key_field->size - 1) 5224 size = key_field->size - 1; 5225 5226 strncpy(compound_key + key_field->offset, (char *)key, size); 5227 } else 5228 memcpy(compound_key + key_field->offset, key, size); 5229 } 5230 5231 static void 5232 hist_trigger_actions(struct hist_trigger_data *hist_data, 5233 struct tracing_map_elt *elt, 5234 struct trace_buffer *buffer, void *rec, 5235 struct ring_buffer_event *rbe, void *key, 5236 u64 *var_ref_vals) 5237 { 5238 struct action_data *data; 5239 unsigned int i; 5240 5241 for (i = 0; i < hist_data->n_actions; i++) { 5242 data = hist_data->actions[i]; 5243 data->fn(hist_data, elt, buffer, rec, rbe, key, data, var_ref_vals); 5244 } 5245 } 5246 5247 static void event_hist_trigger(struct event_trigger_data *data, 5248 struct trace_buffer *buffer, void *rec, 5249 struct ring_buffer_event *rbe) 5250 { 5251 struct hist_trigger_data *hist_data = data->private_data; 5252 bool use_compound_key = (hist_data->n_keys > 1); 5253 unsigned long entries[HIST_STACKTRACE_DEPTH]; 5254 u64 var_ref_vals[TRACING_MAP_VARS_MAX]; 5255 char compound_key[HIST_KEY_SIZE_MAX]; 5256 struct tracing_map_elt *elt = NULL; 5257 struct hist_field *key_field; 5258 u64 field_contents; 5259 void *key = NULL; 5260 unsigned int i; 5261 5262 if (unlikely(!rbe)) 5263 return; 5264 5265 memset(compound_key, 0, hist_data->key_size); 5266 5267 for_each_hist_key_field(i, hist_data) { 5268 key_field = hist_data->fields[i]; 5269 5270 if (key_field->flags & HIST_FIELD_FL_STACKTRACE) { 5271 memset(entries, 0, HIST_STACKTRACE_SIZE); 5272 if (key_field->field) { 5273 unsigned long *stack, n_entries; 5274 5275 field_contents = hist_fn_call(key_field, elt, buffer, rbe, rec); 5276 stack = (unsigned long *)(long)field_contents; 5277 n_entries = *stack; 5278 memcpy(entries, ++stack, n_entries * sizeof(unsigned long)); 5279 } else { 5280 stack_trace_save(entries, HIST_STACKTRACE_DEPTH, 5281 HIST_STACKTRACE_SKIP); 5282 } 5283 key = entries; 5284 } else { 5285 field_contents = hist_fn_call(key_field, elt, buffer, rbe, rec); 5286 if (key_field->flags & HIST_FIELD_FL_STRING) { 5287 key = (void *)(unsigned long)field_contents; 5288 use_compound_key = true; 5289 } else 5290 key = (void *)&field_contents; 5291 } 5292 5293 if (use_compound_key) 5294 add_to_key(compound_key, key, key_field, rec); 5295 } 5296 5297 if (use_compound_key) 5298 key = compound_key; 5299 5300 if (hist_data->n_var_refs && 5301 !resolve_var_refs(hist_data, key, var_ref_vals, false)) 5302 return; 5303 5304 elt = tracing_map_insert(hist_data->map, key); 5305 if (!elt) 5306 return; 5307 5308 hist_trigger_elt_update(hist_data, elt, buffer, rec, rbe, var_ref_vals); 5309 5310 if (resolve_var_refs(hist_data, key, var_ref_vals, true)) 5311 hist_trigger_actions(hist_data, elt, buffer, rec, rbe, key, var_ref_vals); 5312 } 5313 5314 static void hist_trigger_stacktrace_print(struct seq_file *m, 5315 unsigned long *stacktrace_entries, 5316 unsigned int max_entries) 5317 { 5318 unsigned int spaces = 8; 5319 unsigned int i; 5320 5321 for (i = 0; i < max_entries; i++) { 5322 if (!stacktrace_entries[i]) 5323 return; 5324 5325 seq_printf(m, "%*c", 1 + spaces, ' '); 5326 seq_printf(m, "%pS\n", (void*)stacktrace_entries[i]); 5327 } 5328 } 5329 5330 static void hist_trigger_print_key(struct seq_file *m, 5331 struct hist_trigger_data *hist_data, 5332 void *key, 5333 struct tracing_map_elt *elt) 5334 { 5335 struct hist_field *key_field; 5336 bool multiline = false; 5337 const char *field_name; 5338 unsigned int i; 5339 u64 uval; 5340 5341 seq_puts(m, "{ "); 5342 5343 for_each_hist_key_field(i, hist_data) { 5344 key_field = hist_data->fields[i]; 5345 5346 if (i > hist_data->n_vals) 5347 seq_puts(m, ", "); 5348 5349 field_name = hist_field_name(key_field, 0); 5350 5351 if (key_field->flags & HIST_FIELD_FL_HEX) { 5352 uval = *(u64 *)(key + key_field->offset); 5353 seq_printf(m, "%s: %llx", field_name, uval); 5354 } else if (key_field->flags & HIST_FIELD_FL_SYM) { 5355 uval = *(u64 *)(key + key_field->offset); 5356 seq_printf(m, "%s: [%llx] %-45ps", field_name, 5357 uval, (void *)(uintptr_t)uval); 5358 } else if (key_field->flags & HIST_FIELD_FL_SYM_OFFSET) { 5359 uval = *(u64 *)(key + key_field->offset); 5360 seq_printf(m, "%s: [%llx] %-55pS", field_name, 5361 uval, (void *)(uintptr_t)uval); 5362 } else if (key_field->flags & HIST_FIELD_FL_EXECNAME) { 5363 struct hist_elt_data *elt_data = elt->private_data; 5364 char *comm; 5365 5366 if (WARN_ON_ONCE(!elt_data)) 5367 return; 5368 5369 comm = elt_data->comm; 5370 5371 uval = *(u64 *)(key + key_field->offset); 5372 seq_printf(m, "%s: %-16s[%10llu]", field_name, 5373 comm, uval); 5374 } else if (key_field->flags & HIST_FIELD_FL_SYSCALL) { 5375 const char *syscall_name; 5376 5377 uval = *(u64 *)(key + key_field->offset); 5378 syscall_name = get_syscall_name(uval); 5379 if (!syscall_name) 5380 syscall_name = "unknown_syscall"; 5381 5382 seq_printf(m, "%s: %-30s[%3llu]", field_name, 5383 syscall_name, uval); 5384 } else if (key_field->flags & HIST_FIELD_FL_STACKTRACE) { 5385 if (key_field->field) 5386 seq_printf(m, "%s.stacktrace", key_field->field->name); 5387 else 5388 seq_puts(m, "stacktrace:\n"); 5389 hist_trigger_stacktrace_print(m, 5390 key + key_field->offset, 5391 HIST_STACKTRACE_DEPTH); 5392 multiline = true; 5393 } else if (key_field->flags & HIST_FIELD_FL_LOG2) { 5394 seq_printf(m, "%s: ~ 2^%-2llu", field_name, 5395 *(u64 *)(key + key_field->offset)); 5396 } else if (key_field->flags & HIST_FIELD_FL_BUCKET) { 5397 unsigned long buckets = key_field->buckets; 5398 uval = *(u64 *)(key + key_field->offset); 5399 seq_printf(m, "%s: ~ %llu-%llu", field_name, 5400 uval, uval + buckets -1); 5401 } else if (key_field->flags & HIST_FIELD_FL_STRING) { 5402 seq_printf(m, "%s: %-50s", field_name, 5403 (char *)(key + key_field->offset)); 5404 } else { 5405 uval = *(u64 *)(key + key_field->offset); 5406 seq_printf(m, "%s: %10llu", field_name, uval); 5407 } 5408 } 5409 5410 if (!multiline) 5411 seq_puts(m, " "); 5412 5413 seq_puts(m, "}"); 5414 } 5415 5416 /* Get the 100 times of the percentage of @val in @total */ 5417 static inline unsigned int __get_percentage(u64 val, u64 total) 5418 { 5419 if (!total) 5420 goto div0; 5421 5422 if (val < (U64_MAX / 10000)) 5423 return (unsigned int)div64_ul(val * 10000, total); 5424 5425 total = div64_u64(total, 10000); 5426 if (!total) 5427 goto div0; 5428 5429 return (unsigned int)div64_ul(val, total); 5430 div0: 5431 return val ? UINT_MAX : 0; 5432 } 5433 5434 #define BAR_CHAR '#' 5435 5436 static inline const char *__fill_bar_str(char *buf, int size, u64 val, u64 max) 5437 { 5438 unsigned int len = __get_percentage(val, max); 5439 int i; 5440 5441 if (len == UINT_MAX) { 5442 snprintf(buf, size, "[ERROR]"); 5443 return buf; 5444 } 5445 5446 len = len * size / 10000; 5447 for (i = 0; i < len && i < size; i++) 5448 buf[i] = BAR_CHAR; 5449 while (i < size) 5450 buf[i++] = ' '; 5451 buf[size] = '\0'; 5452 5453 return buf; 5454 } 5455 5456 struct hist_val_stat { 5457 u64 max; 5458 u64 total; 5459 }; 5460 5461 static void hist_trigger_print_val(struct seq_file *m, unsigned int idx, 5462 const char *field_name, unsigned long flags, 5463 struct hist_val_stat *stats, 5464 struct tracing_map_elt *elt) 5465 { 5466 u64 val = tracing_map_read_sum(elt, idx); 5467 unsigned int pc; 5468 char bar[21]; 5469 5470 if (flags & HIST_FIELD_FL_PERCENT) { 5471 pc = __get_percentage(val, stats[idx].total); 5472 if (pc == UINT_MAX) 5473 seq_printf(m, " %s (%%):[ERROR]", field_name); 5474 else 5475 seq_printf(m, " %s (%%): %3u.%02u", field_name, 5476 pc / 100, pc % 100); 5477 } else if (flags & HIST_FIELD_FL_GRAPH) { 5478 seq_printf(m, " %s: %20s", field_name, 5479 __fill_bar_str(bar, 20, val, stats[idx].max)); 5480 } else if (flags & HIST_FIELD_FL_HEX) { 5481 seq_printf(m, " %s: %10llx", field_name, val); 5482 } else { 5483 seq_printf(m, " %s: %10llu", field_name, val); 5484 } 5485 } 5486 5487 static void hist_trigger_entry_print(struct seq_file *m, 5488 struct hist_trigger_data *hist_data, 5489 struct hist_val_stat *stats, 5490 void *key, 5491 struct tracing_map_elt *elt) 5492 { 5493 const char *field_name; 5494 unsigned int i = HITCOUNT_IDX; 5495 unsigned long flags; 5496 5497 hist_trigger_print_key(m, hist_data, key, elt); 5498 5499 /* At first, show the raw hitcount if !nohitcount */ 5500 if (!hist_data->attrs->no_hitcount) 5501 hist_trigger_print_val(m, i, "hitcount", 0, stats, elt); 5502 5503 for (i = 1; i < hist_data->n_vals; i++) { 5504 field_name = hist_field_name(hist_data->fields[i], 0); 5505 flags = hist_data->fields[i]->flags; 5506 if (flags & HIST_FIELD_FL_VAR || flags & HIST_FIELD_FL_EXPR) 5507 continue; 5508 5509 seq_puts(m, " "); 5510 hist_trigger_print_val(m, i, field_name, flags, stats, elt); 5511 } 5512 5513 print_actions(m, hist_data, elt); 5514 5515 seq_puts(m, "\n"); 5516 } 5517 5518 static int print_entries(struct seq_file *m, 5519 struct hist_trigger_data *hist_data) 5520 { 5521 struct tracing_map_sort_entry **sort_entries = NULL; 5522 struct tracing_map *map = hist_data->map; 5523 int i, j, n_entries; 5524 struct hist_val_stat *stats = NULL; 5525 u64 val; 5526 5527 n_entries = tracing_map_sort_entries(map, hist_data->sort_keys, 5528 hist_data->n_sort_keys, 5529 &sort_entries); 5530 if (n_entries < 0) 5531 return n_entries; 5532 5533 /* Calculate the max and the total for each field if needed. */ 5534 for (j = 0; j < hist_data->n_vals; j++) { 5535 if (!(hist_data->fields[j]->flags & 5536 (HIST_FIELD_FL_PERCENT | HIST_FIELD_FL_GRAPH))) 5537 continue; 5538 if (!stats) { 5539 stats = kcalloc(hist_data->n_vals, sizeof(*stats), 5540 GFP_KERNEL); 5541 if (!stats) { 5542 n_entries = -ENOMEM; 5543 goto out; 5544 } 5545 } 5546 for (i = 0; i < n_entries; i++) { 5547 val = tracing_map_read_sum(sort_entries[i]->elt, j); 5548 stats[j].total += val; 5549 if (stats[j].max < val) 5550 stats[j].max = val; 5551 } 5552 } 5553 5554 for (i = 0; i < n_entries; i++) 5555 hist_trigger_entry_print(m, hist_data, stats, 5556 sort_entries[i]->key, 5557 sort_entries[i]->elt); 5558 5559 kfree(stats); 5560 out: 5561 tracing_map_destroy_sort_entries(sort_entries, n_entries); 5562 5563 return n_entries; 5564 } 5565 5566 static void hist_trigger_show(struct seq_file *m, 5567 struct event_trigger_data *data, int n) 5568 { 5569 struct hist_trigger_data *hist_data; 5570 int n_entries; 5571 5572 if (n > 0) 5573 seq_puts(m, "\n\n"); 5574 5575 seq_puts(m, "# event histogram\n#\n# trigger info: "); 5576 data->ops->print(m, data); 5577 seq_puts(m, "#\n\n"); 5578 5579 hist_data = data->private_data; 5580 n_entries = print_entries(m, hist_data); 5581 if (n_entries < 0) 5582 n_entries = 0; 5583 5584 track_data_snapshot_print(m, hist_data); 5585 5586 seq_printf(m, "\nTotals:\n Hits: %llu\n Entries: %u\n Dropped: %llu\n", 5587 (u64)atomic64_read(&hist_data->map->hits), 5588 n_entries, (u64)atomic64_read(&hist_data->map->drops)); 5589 } 5590 5591 static int hist_show(struct seq_file *m, void *v) 5592 { 5593 struct event_trigger_data *data; 5594 struct trace_event_file *event_file; 5595 int n = 0, ret = 0; 5596 5597 mutex_lock(&event_mutex); 5598 5599 event_file = event_file_data(m->private); 5600 if (unlikely(!event_file)) { 5601 ret = -ENODEV; 5602 goto out_unlock; 5603 } 5604 5605 list_for_each_entry(data, &event_file->triggers, list) { 5606 if (data->cmd_ops->trigger_type == ETT_EVENT_HIST) 5607 hist_trigger_show(m, data, n++); 5608 } 5609 5610 out_unlock: 5611 mutex_unlock(&event_mutex); 5612 5613 return ret; 5614 } 5615 5616 static int event_hist_open(struct inode *inode, struct file *file) 5617 { 5618 int ret; 5619 5620 ret = security_locked_down(LOCKDOWN_TRACEFS); 5621 if (ret) 5622 return ret; 5623 5624 return single_open(file, hist_show, file); 5625 } 5626 5627 const struct file_operations event_hist_fops = { 5628 .open = event_hist_open, 5629 .read = seq_read, 5630 .llseek = seq_lseek, 5631 .release = single_release, 5632 }; 5633 5634 #ifdef CONFIG_HIST_TRIGGERS_DEBUG 5635 static void hist_field_debug_show_flags(struct seq_file *m, 5636 unsigned long flags) 5637 { 5638 seq_puts(m, " flags:\n"); 5639 5640 if (flags & HIST_FIELD_FL_KEY) 5641 seq_puts(m, " HIST_FIELD_FL_KEY\n"); 5642 else if (flags & HIST_FIELD_FL_HITCOUNT) 5643 seq_puts(m, " VAL: HIST_FIELD_FL_HITCOUNT\n"); 5644 else if (flags & HIST_FIELD_FL_VAR) 5645 seq_puts(m, " HIST_FIELD_FL_VAR\n"); 5646 else if (flags & HIST_FIELD_FL_VAR_REF) 5647 seq_puts(m, " HIST_FIELD_FL_VAR_REF\n"); 5648 else 5649 seq_puts(m, " VAL: normal u64 value\n"); 5650 5651 if (flags & HIST_FIELD_FL_ALIAS) 5652 seq_puts(m, " HIST_FIELD_FL_ALIAS\n"); 5653 else if (flags & HIST_FIELD_FL_CONST) 5654 seq_puts(m, " HIST_FIELD_FL_CONST\n"); 5655 } 5656 5657 static int hist_field_debug_show(struct seq_file *m, 5658 struct hist_field *field, unsigned long flags) 5659 { 5660 if ((field->flags & flags) != flags) { 5661 seq_printf(m, "ERROR: bad flags - %lx\n", flags); 5662 return -EINVAL; 5663 } 5664 5665 hist_field_debug_show_flags(m, field->flags); 5666 if (field->field) 5667 seq_printf(m, " ftrace_event_field name: %s\n", 5668 field->field->name); 5669 5670 if (field->flags & HIST_FIELD_FL_VAR) { 5671 seq_printf(m, " var.name: %s\n", field->var.name); 5672 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n", 5673 field->var.idx); 5674 } 5675 5676 if (field->flags & HIST_FIELD_FL_CONST) 5677 seq_printf(m, " constant: %llu\n", field->constant); 5678 5679 if (field->flags & HIST_FIELD_FL_ALIAS) 5680 seq_printf(m, " var_ref_idx (into hist_data->var_refs[]): %u\n", 5681 field->var_ref_idx); 5682 5683 if (field->flags & HIST_FIELD_FL_VAR_REF) { 5684 seq_printf(m, " name: %s\n", field->name); 5685 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n", 5686 field->var.idx); 5687 seq_printf(m, " var.hist_data: %p\n", field->var.hist_data); 5688 seq_printf(m, " var_ref_idx (into hist_data->var_refs[]): %u\n", 5689 field->var_ref_idx); 5690 if (field->system) 5691 seq_printf(m, " system: %s\n", field->system); 5692 if (field->event_name) 5693 seq_printf(m, " event_name: %s\n", field->event_name); 5694 } 5695 5696 seq_printf(m, " type: %s\n", field->type); 5697 seq_printf(m, " size: %u\n", field->size); 5698 seq_printf(m, " is_signed: %u\n", field->is_signed); 5699 5700 return 0; 5701 } 5702 5703 static int field_var_debug_show(struct seq_file *m, 5704 struct field_var *field_var, unsigned int i, 5705 bool save_vars) 5706 { 5707 const char *vars_name = save_vars ? "save_vars" : "field_vars"; 5708 struct hist_field *field; 5709 int ret = 0; 5710 5711 seq_printf(m, "\n hist_data->%s[%d]:\n", vars_name, i); 5712 5713 field = field_var->var; 5714 5715 seq_printf(m, "\n %s[%d].var:\n", vars_name, i); 5716 5717 hist_field_debug_show_flags(m, field->flags); 5718 seq_printf(m, " var.name: %s\n", field->var.name); 5719 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n", 5720 field->var.idx); 5721 5722 field = field_var->val; 5723 5724 seq_printf(m, "\n %s[%d].val:\n", vars_name, i); 5725 if (field->field) 5726 seq_printf(m, " ftrace_event_field name: %s\n", 5727 field->field->name); 5728 else { 5729 ret = -EINVAL; 5730 goto out; 5731 } 5732 5733 seq_printf(m, " type: %s\n", field->type); 5734 seq_printf(m, " size: %u\n", field->size); 5735 seq_printf(m, " is_signed: %u\n", field->is_signed); 5736 out: 5737 return ret; 5738 } 5739 5740 static int hist_action_debug_show(struct seq_file *m, 5741 struct action_data *data, int i) 5742 { 5743 int ret = 0; 5744 5745 if (data->handler == HANDLER_ONMAX || 5746 data->handler == HANDLER_ONCHANGE) { 5747 seq_printf(m, "\n hist_data->actions[%d].track_data.var_ref:\n", i); 5748 ret = hist_field_debug_show(m, data->track_data.var_ref, 5749 HIST_FIELD_FL_VAR_REF); 5750 if (ret) 5751 goto out; 5752 5753 seq_printf(m, "\n hist_data->actions[%d].track_data.track_var:\n", i); 5754 ret = hist_field_debug_show(m, data->track_data.track_var, 5755 HIST_FIELD_FL_VAR); 5756 if (ret) 5757 goto out; 5758 } 5759 5760 if (data->handler == HANDLER_ONMATCH) { 5761 seq_printf(m, "\n hist_data->actions[%d].match_data.event_system: %s\n", 5762 i, data->match_data.event_system); 5763 seq_printf(m, " hist_data->actions[%d].match_data.event: %s\n", 5764 i, data->match_data.event); 5765 } 5766 out: 5767 return ret; 5768 } 5769 5770 static int hist_actions_debug_show(struct seq_file *m, 5771 struct hist_trigger_data *hist_data) 5772 { 5773 int i, ret = 0; 5774 5775 if (hist_data->n_actions) 5776 seq_puts(m, "\n action tracking variables (for onmax()/onchange()/onmatch()):\n"); 5777 5778 for (i = 0; i < hist_data->n_actions; i++) { 5779 struct action_data *action = hist_data->actions[i]; 5780 5781 ret = hist_action_debug_show(m, action, i); 5782 if (ret) 5783 goto out; 5784 } 5785 5786 if (hist_data->n_save_vars) 5787 seq_puts(m, "\n save action variables (save() params):\n"); 5788 5789 for (i = 0; i < hist_data->n_save_vars; i++) { 5790 ret = field_var_debug_show(m, hist_data->save_vars[i], i, true); 5791 if (ret) 5792 goto out; 5793 } 5794 out: 5795 return ret; 5796 } 5797 5798 static void hist_trigger_debug_show(struct seq_file *m, 5799 struct event_trigger_data *data, int n) 5800 { 5801 struct hist_trigger_data *hist_data; 5802 int i, ret; 5803 5804 if (n > 0) 5805 seq_puts(m, "\n\n"); 5806 5807 seq_puts(m, "# event histogram\n#\n# trigger info: "); 5808 data->ops->print(m, data); 5809 seq_puts(m, "#\n\n"); 5810 5811 hist_data = data->private_data; 5812 5813 seq_printf(m, "hist_data: %p\n\n", hist_data); 5814 seq_printf(m, " n_vals: %u\n", hist_data->n_vals); 5815 seq_printf(m, " n_keys: %u\n", hist_data->n_keys); 5816 seq_printf(m, " n_fields: %u\n", hist_data->n_fields); 5817 5818 seq_puts(m, "\n val fields:\n\n"); 5819 5820 seq_puts(m, " hist_data->fields[0]:\n"); 5821 ret = hist_field_debug_show(m, hist_data->fields[0], 5822 HIST_FIELD_FL_HITCOUNT); 5823 if (ret) 5824 return; 5825 5826 for (i = 1; i < hist_data->n_vals; i++) { 5827 seq_printf(m, "\n hist_data->fields[%d]:\n", i); 5828 ret = hist_field_debug_show(m, hist_data->fields[i], 0); 5829 if (ret) 5830 return; 5831 } 5832 5833 seq_puts(m, "\n key fields:\n"); 5834 5835 for (i = hist_data->n_vals; i < hist_data->n_fields; i++) { 5836 seq_printf(m, "\n hist_data->fields[%d]:\n", i); 5837 ret = hist_field_debug_show(m, hist_data->fields[i], 5838 HIST_FIELD_FL_KEY); 5839 if (ret) 5840 return; 5841 } 5842 5843 if (hist_data->n_var_refs) 5844 seq_puts(m, "\n variable reference fields:\n"); 5845 5846 for (i = 0; i < hist_data->n_var_refs; i++) { 5847 seq_printf(m, "\n hist_data->var_refs[%d]:\n", i); 5848 ret = hist_field_debug_show(m, hist_data->var_refs[i], 5849 HIST_FIELD_FL_VAR_REF); 5850 if (ret) 5851 return; 5852 } 5853 5854 if (hist_data->n_field_vars) 5855 seq_puts(m, "\n field variables:\n"); 5856 5857 for (i = 0; i < hist_data->n_field_vars; i++) { 5858 ret = field_var_debug_show(m, hist_data->field_vars[i], i, false); 5859 if (ret) 5860 return; 5861 } 5862 5863 ret = hist_actions_debug_show(m, hist_data); 5864 if (ret) 5865 return; 5866 } 5867 5868 static int hist_debug_show(struct seq_file *m, void *v) 5869 { 5870 struct event_trigger_data *data; 5871 struct trace_event_file *event_file; 5872 int n = 0, ret = 0; 5873 5874 mutex_lock(&event_mutex); 5875 5876 event_file = event_file_data(m->private); 5877 if (unlikely(!event_file)) { 5878 ret = -ENODEV; 5879 goto out_unlock; 5880 } 5881 5882 list_for_each_entry(data, &event_file->triggers, list) { 5883 if (data->cmd_ops->trigger_type == ETT_EVENT_HIST) 5884 hist_trigger_debug_show(m, data, n++); 5885 } 5886 5887 out_unlock: 5888 mutex_unlock(&event_mutex); 5889 5890 return ret; 5891 } 5892 5893 static int event_hist_debug_open(struct inode *inode, struct file *file) 5894 { 5895 int ret; 5896 5897 ret = security_locked_down(LOCKDOWN_TRACEFS); 5898 if (ret) 5899 return ret; 5900 5901 return single_open(file, hist_debug_show, file); 5902 } 5903 5904 const struct file_operations event_hist_debug_fops = { 5905 .open = event_hist_debug_open, 5906 .read = seq_read, 5907 .llseek = seq_lseek, 5908 .release = single_release, 5909 }; 5910 #endif 5911 5912 static void hist_field_print(struct seq_file *m, struct hist_field *hist_field) 5913 { 5914 const char *field_name = hist_field_name(hist_field, 0); 5915 5916 if (hist_field->var.name) 5917 seq_printf(m, "%s=", hist_field->var.name); 5918 5919 if (hist_field->flags & HIST_FIELD_FL_CPU) 5920 seq_puts(m, "common_cpu"); 5921 else if (hist_field->flags & HIST_FIELD_FL_CONST) 5922 seq_printf(m, "%llu", hist_field->constant); 5923 else if (field_name) { 5924 if (hist_field->flags & HIST_FIELD_FL_VAR_REF || 5925 hist_field->flags & HIST_FIELD_FL_ALIAS) 5926 seq_putc(m, '$'); 5927 seq_printf(m, "%s", field_name); 5928 } else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP) 5929 seq_puts(m, "common_timestamp"); 5930 5931 if (hist_field->flags) { 5932 if (!(hist_field->flags & HIST_FIELD_FL_VAR_REF) && 5933 !(hist_field->flags & HIST_FIELD_FL_EXPR) && 5934 !(hist_field->flags & HIST_FIELD_FL_STACKTRACE)) { 5935 const char *flags = get_hist_field_flags(hist_field); 5936 5937 if (flags) 5938 seq_printf(m, ".%s", flags); 5939 } 5940 } 5941 if (hist_field->buckets) 5942 seq_printf(m, "=%ld", hist_field->buckets); 5943 } 5944 5945 static int event_hist_trigger_print(struct seq_file *m, 5946 struct event_trigger_data *data) 5947 { 5948 struct hist_trigger_data *hist_data = data->private_data; 5949 struct hist_field *field; 5950 bool have_var = false; 5951 bool show_val = false; 5952 unsigned int i; 5953 5954 seq_puts(m, HIST_PREFIX); 5955 5956 if (data->name) 5957 seq_printf(m, "%s:", data->name); 5958 5959 seq_puts(m, "keys="); 5960 5961 for_each_hist_key_field(i, hist_data) { 5962 field = hist_data->fields[i]; 5963 5964 if (i > hist_data->n_vals) 5965 seq_puts(m, ","); 5966 5967 if (field->flags & HIST_FIELD_FL_STACKTRACE) { 5968 if (field->field) 5969 seq_printf(m, "%s.stacktrace", field->field->name); 5970 else 5971 seq_puts(m, "stacktrace"); 5972 } else 5973 hist_field_print(m, field); 5974 } 5975 5976 seq_puts(m, ":vals="); 5977 5978 for_each_hist_val_field(i, hist_data) { 5979 field = hist_data->fields[i]; 5980 if (field->flags & HIST_FIELD_FL_VAR) { 5981 have_var = true; 5982 continue; 5983 } 5984 5985 if (i == HITCOUNT_IDX) { 5986 if (hist_data->attrs->no_hitcount) 5987 continue; 5988 seq_puts(m, "hitcount"); 5989 } else { 5990 if (show_val) 5991 seq_puts(m, ","); 5992 hist_field_print(m, field); 5993 } 5994 show_val = true; 5995 } 5996 5997 if (have_var) { 5998 unsigned int n = 0; 5999 6000 seq_puts(m, ":"); 6001 6002 for_each_hist_val_field(i, hist_data) { 6003 field = hist_data->fields[i]; 6004 6005 if (field->flags & HIST_FIELD_FL_VAR) { 6006 if (n++) 6007 seq_puts(m, ","); 6008 hist_field_print(m, field); 6009 } 6010 } 6011 } 6012 6013 seq_puts(m, ":sort="); 6014 6015 for (i = 0; i < hist_data->n_sort_keys; i++) { 6016 struct tracing_map_sort_key *sort_key; 6017 unsigned int idx, first_key_idx; 6018 6019 /* skip VAR vals */ 6020 first_key_idx = hist_data->n_vals - hist_data->n_vars; 6021 6022 sort_key = &hist_data->sort_keys[i]; 6023 idx = sort_key->field_idx; 6024 6025 if (WARN_ON(idx >= HIST_FIELDS_MAX)) 6026 return -EINVAL; 6027 6028 if (i > 0) 6029 seq_puts(m, ","); 6030 6031 if (idx == HITCOUNT_IDX) 6032 seq_puts(m, "hitcount"); 6033 else { 6034 if (idx >= first_key_idx) 6035 idx += hist_data->n_vars; 6036 hist_field_print(m, hist_data->fields[idx]); 6037 } 6038 6039 if (sort_key->descending) 6040 seq_puts(m, ".descending"); 6041 } 6042 seq_printf(m, ":size=%u", (1 << hist_data->map->map_bits)); 6043 if (hist_data->enable_timestamps) 6044 seq_printf(m, ":clock=%s", hist_data->attrs->clock); 6045 if (hist_data->attrs->no_hitcount) 6046 seq_puts(m, ":nohitcount"); 6047 6048 print_actions_spec(m, hist_data); 6049 6050 if (data->filter_str) 6051 seq_printf(m, " if %s", data->filter_str); 6052 6053 if (data->paused) 6054 seq_puts(m, " [paused]"); 6055 else 6056 seq_puts(m, " [active]"); 6057 6058 seq_putc(m, '\n'); 6059 6060 return 0; 6061 } 6062 6063 static int event_hist_trigger_init(struct event_trigger_data *data) 6064 { 6065 struct hist_trigger_data *hist_data = data->private_data; 6066 6067 if (!data->ref && hist_data->attrs->name) 6068 save_named_trigger(hist_data->attrs->name, data); 6069 6070 data->ref++; 6071 6072 return 0; 6073 } 6074 6075 static void unregister_field_var_hists(struct hist_trigger_data *hist_data) 6076 { 6077 struct trace_event_file *file; 6078 unsigned int i; 6079 char *cmd; 6080 int ret; 6081 6082 for (i = 0; i < hist_data->n_field_var_hists; i++) { 6083 file = hist_data->field_var_hists[i]->hist_data->event_file; 6084 cmd = hist_data->field_var_hists[i]->cmd; 6085 ret = event_hist_trigger_parse(&trigger_hist_cmd, file, 6086 "!hist", "hist", cmd); 6087 WARN_ON_ONCE(ret < 0); 6088 } 6089 } 6090 6091 static void event_hist_trigger_free(struct event_trigger_data *data) 6092 { 6093 struct hist_trigger_data *hist_data = data->private_data; 6094 6095 if (WARN_ON_ONCE(data->ref <= 0)) 6096 return; 6097 6098 data->ref--; 6099 if (!data->ref) { 6100 if (data->name) 6101 del_named_trigger(data); 6102 6103 trigger_data_free(data); 6104 6105 remove_hist_vars(hist_data); 6106 6107 unregister_field_var_hists(hist_data); 6108 6109 destroy_hist_data(hist_data); 6110 } 6111 } 6112 6113 static struct event_trigger_ops event_hist_trigger_ops = { 6114 .trigger = event_hist_trigger, 6115 .print = event_hist_trigger_print, 6116 .init = event_hist_trigger_init, 6117 .free = event_hist_trigger_free, 6118 }; 6119 6120 static int event_hist_trigger_named_init(struct event_trigger_data *data) 6121 { 6122 data->ref++; 6123 6124 save_named_trigger(data->named_data->name, data); 6125 6126 event_hist_trigger_init(data->named_data); 6127 6128 return 0; 6129 } 6130 6131 static void event_hist_trigger_named_free(struct event_trigger_data *data) 6132 { 6133 if (WARN_ON_ONCE(data->ref <= 0)) 6134 return; 6135 6136 event_hist_trigger_free(data->named_data); 6137 6138 data->ref--; 6139 if (!data->ref) { 6140 del_named_trigger(data); 6141 trigger_data_free(data); 6142 } 6143 } 6144 6145 static struct event_trigger_ops event_hist_trigger_named_ops = { 6146 .trigger = event_hist_trigger, 6147 .print = event_hist_trigger_print, 6148 .init = event_hist_trigger_named_init, 6149 .free = event_hist_trigger_named_free, 6150 }; 6151 6152 static struct event_trigger_ops *event_hist_get_trigger_ops(char *cmd, 6153 char *param) 6154 { 6155 return &event_hist_trigger_ops; 6156 } 6157 6158 static void hist_clear(struct event_trigger_data *data) 6159 { 6160 struct hist_trigger_data *hist_data = data->private_data; 6161 6162 if (data->name) 6163 pause_named_trigger(data); 6164 6165 tracepoint_synchronize_unregister(); 6166 6167 tracing_map_clear(hist_data->map); 6168 6169 if (data->name) 6170 unpause_named_trigger(data); 6171 } 6172 6173 static bool compatible_field(struct ftrace_event_field *field, 6174 struct ftrace_event_field *test_field) 6175 { 6176 if (field == test_field) 6177 return true; 6178 if (field == NULL || test_field == NULL) 6179 return false; 6180 if (strcmp(field->name, test_field->name) != 0) 6181 return false; 6182 if (strcmp(field->type, test_field->type) != 0) 6183 return false; 6184 if (field->size != test_field->size) 6185 return false; 6186 if (field->is_signed != test_field->is_signed) 6187 return false; 6188 6189 return true; 6190 } 6191 6192 static bool hist_trigger_match(struct event_trigger_data *data, 6193 struct event_trigger_data *data_test, 6194 struct event_trigger_data *named_data, 6195 bool ignore_filter) 6196 { 6197 struct tracing_map_sort_key *sort_key, *sort_key_test; 6198 struct hist_trigger_data *hist_data, *hist_data_test; 6199 struct hist_field *key_field, *key_field_test; 6200 unsigned int i; 6201 6202 if (named_data && (named_data != data_test) && 6203 (named_data != data_test->named_data)) 6204 return false; 6205 6206 if (!named_data && is_named_trigger(data_test)) 6207 return false; 6208 6209 hist_data = data->private_data; 6210 hist_data_test = data_test->private_data; 6211 6212 if (hist_data->n_vals != hist_data_test->n_vals || 6213 hist_data->n_fields != hist_data_test->n_fields || 6214 hist_data->n_sort_keys != hist_data_test->n_sort_keys) 6215 return false; 6216 6217 if (!ignore_filter) { 6218 if ((data->filter_str && !data_test->filter_str) || 6219 (!data->filter_str && data_test->filter_str)) 6220 return false; 6221 } 6222 6223 for_each_hist_field(i, hist_data) { 6224 key_field = hist_data->fields[i]; 6225 key_field_test = hist_data_test->fields[i]; 6226 6227 if (key_field->flags != key_field_test->flags) 6228 return false; 6229 if (!compatible_field(key_field->field, key_field_test->field)) 6230 return false; 6231 if (key_field->offset != key_field_test->offset) 6232 return false; 6233 if (key_field->size != key_field_test->size) 6234 return false; 6235 if (key_field->is_signed != key_field_test->is_signed) 6236 return false; 6237 if (!!key_field->var.name != !!key_field_test->var.name) 6238 return false; 6239 if (key_field->var.name && 6240 strcmp(key_field->var.name, key_field_test->var.name) != 0) 6241 return false; 6242 } 6243 6244 for (i = 0; i < hist_data->n_sort_keys; i++) { 6245 sort_key = &hist_data->sort_keys[i]; 6246 sort_key_test = &hist_data_test->sort_keys[i]; 6247 6248 if (sort_key->field_idx != sort_key_test->field_idx || 6249 sort_key->descending != sort_key_test->descending) 6250 return false; 6251 } 6252 6253 if (!ignore_filter && data->filter_str && 6254 (strcmp(data->filter_str, data_test->filter_str) != 0)) 6255 return false; 6256 6257 if (!actions_match(hist_data, hist_data_test)) 6258 return false; 6259 6260 return true; 6261 } 6262 6263 static bool existing_hist_update_only(char *glob, 6264 struct event_trigger_data *data, 6265 struct trace_event_file *file) 6266 { 6267 struct hist_trigger_data *hist_data = data->private_data; 6268 struct event_trigger_data *test, *named_data = NULL; 6269 bool updated = false; 6270 6271 if (!hist_data->attrs->pause && !hist_data->attrs->cont && 6272 !hist_data->attrs->clear) 6273 goto out; 6274 6275 if (hist_data->attrs->name) { 6276 named_data = find_named_trigger(hist_data->attrs->name); 6277 if (named_data) { 6278 if (!hist_trigger_match(data, named_data, named_data, 6279 true)) 6280 goto out; 6281 } 6282 } 6283 6284 if (hist_data->attrs->name && !named_data) 6285 goto out; 6286 6287 list_for_each_entry(test, &file->triggers, list) { 6288 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6289 if (!hist_trigger_match(data, test, named_data, false)) 6290 continue; 6291 if (hist_data->attrs->pause) 6292 test->paused = true; 6293 else if (hist_data->attrs->cont) 6294 test->paused = false; 6295 else if (hist_data->attrs->clear) 6296 hist_clear(test); 6297 updated = true; 6298 goto out; 6299 } 6300 } 6301 out: 6302 return updated; 6303 } 6304 6305 static int hist_register_trigger(char *glob, 6306 struct event_trigger_data *data, 6307 struct trace_event_file *file) 6308 { 6309 struct hist_trigger_data *hist_data = data->private_data; 6310 struct event_trigger_data *test, *named_data = NULL; 6311 struct trace_array *tr = file->tr; 6312 int ret = 0; 6313 6314 if (hist_data->attrs->name) { 6315 named_data = find_named_trigger(hist_data->attrs->name); 6316 if (named_data) { 6317 if (!hist_trigger_match(data, named_data, named_data, 6318 true)) { 6319 hist_err(tr, HIST_ERR_NAMED_MISMATCH, errpos(hist_data->attrs->name)); 6320 ret = -EINVAL; 6321 goto out; 6322 } 6323 } 6324 } 6325 6326 if (hist_data->attrs->name && !named_data) 6327 goto new; 6328 6329 lockdep_assert_held(&event_mutex); 6330 6331 list_for_each_entry(test, &file->triggers, list) { 6332 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6333 if (hist_trigger_match(data, test, named_data, false)) { 6334 hist_err(tr, HIST_ERR_TRIGGER_EEXIST, 0); 6335 ret = -EEXIST; 6336 goto out; 6337 } 6338 } 6339 } 6340 new: 6341 if (hist_data->attrs->cont || hist_data->attrs->clear) { 6342 hist_err(tr, HIST_ERR_TRIGGER_ENOENT_CLEAR, 0); 6343 ret = -ENOENT; 6344 goto out; 6345 } 6346 6347 if (hist_data->attrs->pause) 6348 data->paused = true; 6349 6350 if (named_data) { 6351 data->private_data = named_data->private_data; 6352 set_named_trigger_data(data, named_data); 6353 data->ops = &event_hist_trigger_named_ops; 6354 } 6355 6356 if (data->ops->init) { 6357 ret = data->ops->init(data); 6358 if (ret < 0) 6359 goto out; 6360 } 6361 6362 if (hist_data->enable_timestamps) { 6363 char *clock = hist_data->attrs->clock; 6364 6365 ret = tracing_set_clock(file->tr, hist_data->attrs->clock); 6366 if (ret) { 6367 hist_err(tr, HIST_ERR_SET_CLOCK_FAIL, errpos(clock)); 6368 goto out; 6369 } 6370 6371 tracing_set_filter_buffering(file->tr, true); 6372 } 6373 6374 if (named_data) 6375 destroy_hist_data(hist_data); 6376 out: 6377 return ret; 6378 } 6379 6380 static int hist_trigger_enable(struct event_trigger_data *data, 6381 struct trace_event_file *file) 6382 { 6383 int ret = 0; 6384 6385 list_add_tail_rcu(&data->list, &file->triggers); 6386 6387 update_cond_flag(file); 6388 6389 if (trace_event_trigger_enable_disable(file, 1) < 0) { 6390 list_del_rcu(&data->list); 6391 update_cond_flag(file); 6392 ret--; 6393 } 6394 6395 return ret; 6396 } 6397 6398 static bool have_hist_trigger_match(struct event_trigger_data *data, 6399 struct trace_event_file *file) 6400 { 6401 struct hist_trigger_data *hist_data = data->private_data; 6402 struct event_trigger_data *test, *named_data = NULL; 6403 bool match = false; 6404 6405 lockdep_assert_held(&event_mutex); 6406 6407 if (hist_data->attrs->name) 6408 named_data = find_named_trigger(hist_data->attrs->name); 6409 6410 list_for_each_entry(test, &file->triggers, list) { 6411 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6412 if (hist_trigger_match(data, test, named_data, false)) { 6413 match = true; 6414 break; 6415 } 6416 } 6417 } 6418 6419 return match; 6420 } 6421 6422 static bool hist_trigger_check_refs(struct event_trigger_data *data, 6423 struct trace_event_file *file) 6424 { 6425 struct hist_trigger_data *hist_data = data->private_data; 6426 struct event_trigger_data *test, *named_data = NULL; 6427 6428 lockdep_assert_held(&event_mutex); 6429 6430 if (hist_data->attrs->name) 6431 named_data = find_named_trigger(hist_data->attrs->name); 6432 6433 list_for_each_entry(test, &file->triggers, list) { 6434 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6435 if (!hist_trigger_match(data, test, named_data, false)) 6436 continue; 6437 hist_data = test->private_data; 6438 if (check_var_refs(hist_data)) 6439 return true; 6440 break; 6441 } 6442 } 6443 6444 return false; 6445 } 6446 6447 static void hist_unregister_trigger(char *glob, 6448 struct event_trigger_data *data, 6449 struct trace_event_file *file) 6450 { 6451 struct event_trigger_data *test = NULL, *iter, *named_data = NULL; 6452 struct hist_trigger_data *hist_data = data->private_data; 6453 6454 lockdep_assert_held(&event_mutex); 6455 6456 if (hist_data->attrs->name) 6457 named_data = find_named_trigger(hist_data->attrs->name); 6458 6459 list_for_each_entry(iter, &file->triggers, list) { 6460 if (iter->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6461 if (!hist_trigger_match(data, iter, named_data, false)) 6462 continue; 6463 test = iter; 6464 list_del_rcu(&test->list); 6465 trace_event_trigger_enable_disable(file, 0); 6466 update_cond_flag(file); 6467 break; 6468 } 6469 } 6470 6471 if (test && test->ops->free) 6472 test->ops->free(test); 6473 6474 if (hist_data->enable_timestamps) { 6475 if (!hist_data->remove || test) 6476 tracing_set_filter_buffering(file->tr, false); 6477 } 6478 } 6479 6480 static bool hist_file_check_refs(struct trace_event_file *file) 6481 { 6482 struct hist_trigger_data *hist_data; 6483 struct event_trigger_data *test; 6484 6485 lockdep_assert_held(&event_mutex); 6486 6487 list_for_each_entry(test, &file->triggers, list) { 6488 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6489 hist_data = test->private_data; 6490 if (check_var_refs(hist_data)) 6491 return true; 6492 } 6493 } 6494 6495 return false; 6496 } 6497 6498 static void hist_unreg_all(struct trace_event_file *file) 6499 { 6500 struct event_trigger_data *test, *n; 6501 struct hist_trigger_data *hist_data; 6502 struct synth_event *se; 6503 const char *se_name; 6504 6505 lockdep_assert_held(&event_mutex); 6506 6507 if (hist_file_check_refs(file)) 6508 return; 6509 6510 list_for_each_entry_safe(test, n, &file->triggers, list) { 6511 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6512 hist_data = test->private_data; 6513 list_del_rcu(&test->list); 6514 trace_event_trigger_enable_disable(file, 0); 6515 6516 se_name = trace_event_name(file->event_call); 6517 se = find_synth_event(se_name); 6518 if (se) 6519 se->ref--; 6520 6521 update_cond_flag(file); 6522 if (hist_data->enable_timestamps) 6523 tracing_set_filter_buffering(file->tr, false); 6524 if (test->ops->free) 6525 test->ops->free(test); 6526 } 6527 } 6528 } 6529 6530 static int event_hist_trigger_parse(struct event_command *cmd_ops, 6531 struct trace_event_file *file, 6532 char *glob, char *cmd, 6533 char *param_and_filter) 6534 { 6535 unsigned int hist_trigger_bits = TRACING_MAP_BITS_DEFAULT; 6536 struct event_trigger_data *trigger_data; 6537 struct hist_trigger_attrs *attrs; 6538 struct hist_trigger_data *hist_data; 6539 char *param, *filter, *p, *start; 6540 struct synth_event *se; 6541 const char *se_name; 6542 bool remove; 6543 int ret = 0; 6544 6545 lockdep_assert_held(&event_mutex); 6546 6547 if (WARN_ON(!glob)) 6548 return -EINVAL; 6549 6550 if (glob[0]) { 6551 hist_err_clear(); 6552 last_cmd_set(file, param_and_filter); 6553 } 6554 6555 remove = event_trigger_check_remove(glob); 6556 6557 if (event_trigger_empty_param(param_and_filter)) 6558 return -EINVAL; 6559 6560 /* 6561 * separate the trigger from the filter (k:v [if filter]) 6562 * allowing for whitespace in the trigger 6563 */ 6564 p = param = param_and_filter; 6565 do { 6566 p = strstr(p, "if"); 6567 if (!p) 6568 break; 6569 if (p == param_and_filter) 6570 return -EINVAL; 6571 if (*(p - 1) != ' ' && *(p - 1) != '\t') { 6572 p++; 6573 continue; 6574 } 6575 if (p >= param_and_filter + strlen(param_and_filter) - (sizeof("if") - 1) - 1) 6576 return -EINVAL; 6577 if (*(p + sizeof("if") - 1) != ' ' && *(p + sizeof("if") - 1) != '\t') { 6578 p++; 6579 continue; 6580 } 6581 break; 6582 } while (1); 6583 6584 if (!p) 6585 filter = NULL; 6586 else { 6587 *(p - 1) = '\0'; 6588 filter = strstrip(p); 6589 param = strstrip(param); 6590 } 6591 6592 /* 6593 * To simplify arithmetic expression parsing, replace occurrences of 6594 * '.sym-offset' modifier with '.symXoffset' 6595 */ 6596 start = strstr(param, ".sym-offset"); 6597 while (start) { 6598 *(start + 4) = 'X'; 6599 start = strstr(start + 11, ".sym-offset"); 6600 } 6601 6602 attrs = parse_hist_trigger_attrs(file->tr, param); 6603 if (IS_ERR(attrs)) 6604 return PTR_ERR(attrs); 6605 6606 if (attrs->map_bits) 6607 hist_trigger_bits = attrs->map_bits; 6608 6609 hist_data = create_hist_data(hist_trigger_bits, attrs, file, remove); 6610 if (IS_ERR(hist_data)) { 6611 destroy_hist_trigger_attrs(attrs); 6612 return PTR_ERR(hist_data); 6613 } 6614 6615 trigger_data = event_trigger_alloc(cmd_ops, cmd, param, hist_data); 6616 if (!trigger_data) { 6617 ret = -ENOMEM; 6618 goto out_free; 6619 } 6620 6621 ret = event_trigger_set_filter(cmd_ops, file, filter, trigger_data); 6622 if (ret < 0) 6623 goto out_free; 6624 6625 if (remove) { 6626 if (!have_hist_trigger_match(trigger_data, file)) 6627 goto out_free; 6628 6629 if (hist_trigger_check_refs(trigger_data, file)) { 6630 ret = -EBUSY; 6631 goto out_free; 6632 } 6633 6634 event_trigger_unregister(cmd_ops, file, glob+1, trigger_data); 6635 se_name = trace_event_name(file->event_call); 6636 se = find_synth_event(se_name); 6637 if (se) 6638 se->ref--; 6639 ret = 0; 6640 goto out_free; 6641 } 6642 6643 if (existing_hist_update_only(glob, trigger_data, file)) 6644 goto out_free; 6645 6646 ret = event_trigger_register(cmd_ops, file, glob, trigger_data); 6647 if (ret < 0) 6648 goto out_free; 6649 6650 if (get_named_trigger_data(trigger_data)) 6651 goto enable; 6652 6653 if (has_hist_vars(hist_data)) 6654 save_hist_vars(hist_data); 6655 6656 ret = create_actions(hist_data); 6657 if (ret) 6658 goto out_unreg; 6659 6660 ret = tracing_map_init(hist_data->map); 6661 if (ret) 6662 goto out_unreg; 6663 enable: 6664 ret = hist_trigger_enable(trigger_data, file); 6665 if (ret) 6666 goto out_unreg; 6667 6668 se_name = trace_event_name(file->event_call); 6669 se = find_synth_event(se_name); 6670 if (se) 6671 se->ref++; 6672 out: 6673 if (ret == 0 && glob[0]) 6674 hist_err_clear(); 6675 6676 return ret; 6677 out_unreg: 6678 event_trigger_unregister(cmd_ops, file, glob+1, trigger_data); 6679 out_free: 6680 event_trigger_reset_filter(cmd_ops, trigger_data); 6681 6682 remove_hist_vars(hist_data); 6683 6684 kfree(trigger_data); 6685 6686 destroy_hist_data(hist_data); 6687 goto out; 6688 } 6689 6690 static struct event_command trigger_hist_cmd = { 6691 .name = "hist", 6692 .trigger_type = ETT_EVENT_HIST, 6693 .flags = EVENT_CMD_FL_NEEDS_REC, 6694 .parse = event_hist_trigger_parse, 6695 .reg = hist_register_trigger, 6696 .unreg = hist_unregister_trigger, 6697 .unreg_all = hist_unreg_all, 6698 .get_trigger_ops = event_hist_get_trigger_ops, 6699 .set_filter = set_trigger_filter, 6700 }; 6701 6702 __init int register_trigger_hist_cmd(void) 6703 { 6704 int ret; 6705 6706 ret = register_event_command(&trigger_hist_cmd); 6707 WARN_ON(ret < 0); 6708 6709 return ret; 6710 } 6711 6712 static void 6713 hist_enable_trigger(struct event_trigger_data *data, 6714 struct trace_buffer *buffer, void *rec, 6715 struct ring_buffer_event *event) 6716 { 6717 struct enable_trigger_data *enable_data = data->private_data; 6718 struct event_trigger_data *test; 6719 6720 list_for_each_entry_rcu(test, &enable_data->file->triggers, list, 6721 lockdep_is_held(&event_mutex)) { 6722 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6723 if (enable_data->enable) 6724 test->paused = false; 6725 else 6726 test->paused = true; 6727 } 6728 } 6729 } 6730 6731 static void 6732 hist_enable_count_trigger(struct event_trigger_data *data, 6733 struct trace_buffer *buffer, void *rec, 6734 struct ring_buffer_event *event) 6735 { 6736 if (!data->count) 6737 return; 6738 6739 if (data->count != -1) 6740 (data->count)--; 6741 6742 hist_enable_trigger(data, buffer, rec, event); 6743 } 6744 6745 static struct event_trigger_ops hist_enable_trigger_ops = { 6746 .trigger = hist_enable_trigger, 6747 .print = event_enable_trigger_print, 6748 .init = event_trigger_init, 6749 .free = event_enable_trigger_free, 6750 }; 6751 6752 static struct event_trigger_ops hist_enable_count_trigger_ops = { 6753 .trigger = hist_enable_count_trigger, 6754 .print = event_enable_trigger_print, 6755 .init = event_trigger_init, 6756 .free = event_enable_trigger_free, 6757 }; 6758 6759 static struct event_trigger_ops hist_disable_trigger_ops = { 6760 .trigger = hist_enable_trigger, 6761 .print = event_enable_trigger_print, 6762 .init = event_trigger_init, 6763 .free = event_enable_trigger_free, 6764 }; 6765 6766 static struct event_trigger_ops hist_disable_count_trigger_ops = { 6767 .trigger = hist_enable_count_trigger, 6768 .print = event_enable_trigger_print, 6769 .init = event_trigger_init, 6770 .free = event_enable_trigger_free, 6771 }; 6772 6773 static struct event_trigger_ops * 6774 hist_enable_get_trigger_ops(char *cmd, char *param) 6775 { 6776 struct event_trigger_ops *ops; 6777 bool enable; 6778 6779 enable = (strcmp(cmd, ENABLE_HIST_STR) == 0); 6780 6781 if (enable) 6782 ops = param ? &hist_enable_count_trigger_ops : 6783 &hist_enable_trigger_ops; 6784 else 6785 ops = param ? &hist_disable_count_trigger_ops : 6786 &hist_disable_trigger_ops; 6787 6788 return ops; 6789 } 6790 6791 static void hist_enable_unreg_all(struct trace_event_file *file) 6792 { 6793 struct event_trigger_data *test, *n; 6794 6795 list_for_each_entry_safe(test, n, &file->triggers, list) { 6796 if (test->cmd_ops->trigger_type == ETT_HIST_ENABLE) { 6797 list_del_rcu(&test->list); 6798 update_cond_flag(file); 6799 trace_event_trigger_enable_disable(file, 0); 6800 if (test->ops->free) 6801 test->ops->free(test); 6802 } 6803 } 6804 } 6805 6806 static struct event_command trigger_hist_enable_cmd = { 6807 .name = ENABLE_HIST_STR, 6808 .trigger_type = ETT_HIST_ENABLE, 6809 .parse = event_enable_trigger_parse, 6810 .reg = event_enable_register_trigger, 6811 .unreg = event_enable_unregister_trigger, 6812 .unreg_all = hist_enable_unreg_all, 6813 .get_trigger_ops = hist_enable_get_trigger_ops, 6814 .set_filter = set_trigger_filter, 6815 }; 6816 6817 static struct event_command trigger_hist_disable_cmd = { 6818 .name = DISABLE_HIST_STR, 6819 .trigger_type = ETT_HIST_ENABLE, 6820 .parse = event_enable_trigger_parse, 6821 .reg = event_enable_register_trigger, 6822 .unreg = event_enable_unregister_trigger, 6823 .unreg_all = hist_enable_unreg_all, 6824 .get_trigger_ops = hist_enable_get_trigger_ops, 6825 .set_filter = set_trigger_filter, 6826 }; 6827 6828 static __init void unregister_trigger_hist_enable_disable_cmds(void) 6829 { 6830 unregister_event_command(&trigger_hist_enable_cmd); 6831 unregister_event_command(&trigger_hist_disable_cmd); 6832 } 6833 6834 __init int register_trigger_hist_enable_disable_cmds(void) 6835 { 6836 int ret; 6837 6838 ret = register_event_command(&trigger_hist_enable_cmd); 6839 if (WARN_ON(ret < 0)) 6840 return ret; 6841 ret = register_event_command(&trigger_hist_disable_cmd); 6842 if (WARN_ON(ret < 0)) 6843 unregister_trigger_hist_enable_disable_cmds(); 6844 6845 return ret; 6846 } 6847