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; 777 778 if (!str) 779 return; 780 781 kfree(last_cmd); 782 783 last_cmd = kasprintf(GFP_KERNEL, HIST_PREFIX "%s", str); 784 if (!last_cmd) 785 return; 786 787 if (file) { 788 call = file->event_call; 789 system = call->class->system; 790 if (system) { 791 name = trace_event_name(call); 792 if (!name) 793 system = NULL; 794 } 795 } 796 797 if (system) 798 snprintf(last_cmd_loc, MAX_FILTER_STR_VAL, HIST_PREFIX "%s:%s", system, name); 799 } 800 801 static void hist_err(struct trace_array *tr, u8 err_type, u16 err_pos) 802 { 803 if (!last_cmd) 804 return; 805 806 tracing_log_err(tr, last_cmd_loc, last_cmd, err_text, 807 err_type, err_pos); 808 } 809 810 static void hist_err_clear(void) 811 { 812 if (last_cmd) 813 last_cmd[0] = '\0'; 814 last_cmd_loc[0] = '\0'; 815 } 816 817 typedef void (*synth_probe_func_t) (void *__data, u64 *var_ref_vals, 818 unsigned int *var_ref_idx); 819 820 static inline void trace_synth(struct synth_event *event, u64 *var_ref_vals, 821 unsigned int *var_ref_idx) 822 { 823 struct tracepoint *tp = event->tp; 824 825 if (unlikely(atomic_read(&tp->key.enabled) > 0)) { 826 struct tracepoint_func *probe_func_ptr; 827 synth_probe_func_t probe_func; 828 void *__data; 829 830 if (!(cpu_online(raw_smp_processor_id()))) 831 return; 832 833 probe_func_ptr = rcu_dereference_sched((tp)->funcs); 834 if (probe_func_ptr) { 835 do { 836 probe_func = probe_func_ptr->func; 837 __data = probe_func_ptr->data; 838 probe_func(__data, var_ref_vals, var_ref_idx); 839 } while ((++probe_func_ptr)->func); 840 } 841 } 842 } 843 844 static void action_trace(struct hist_trigger_data *hist_data, 845 struct tracing_map_elt *elt, 846 struct trace_buffer *buffer, void *rec, 847 struct ring_buffer_event *rbe, void *key, 848 struct action_data *data, u64 *var_ref_vals) 849 { 850 struct synth_event *event = data->synth_event; 851 852 trace_synth(event, var_ref_vals, data->var_ref_idx); 853 } 854 855 struct hist_var_data { 856 struct list_head list; 857 struct hist_trigger_data *hist_data; 858 }; 859 860 static u64 hist_field_timestamp(struct hist_field *hist_field, 861 struct tracing_map_elt *elt, 862 struct trace_buffer *buffer, 863 struct ring_buffer_event *rbe, 864 void *event) 865 { 866 struct hist_trigger_data *hist_data = hist_field->hist_data; 867 struct trace_array *tr = hist_data->event_file->tr; 868 869 u64 ts = ring_buffer_event_time_stamp(buffer, rbe); 870 871 if (hist_data->attrs->ts_in_usecs && trace_clock_in_ns(tr)) 872 ts = ns2usecs(ts); 873 874 return ts; 875 } 876 877 static u64 hist_field_cpu(struct hist_field *hist_field, 878 struct tracing_map_elt *elt, 879 struct trace_buffer *buffer, 880 struct ring_buffer_event *rbe, 881 void *event) 882 { 883 int cpu = smp_processor_id(); 884 885 return cpu; 886 } 887 888 /** 889 * check_field_for_var_ref - Check if a VAR_REF field references a variable 890 * @hist_field: The VAR_REF field to check 891 * @var_data: The hist trigger that owns the variable 892 * @var_idx: The trigger variable identifier 893 * 894 * Check the given VAR_REF field to see whether or not it references 895 * the given variable associated with the given trigger. 896 * 897 * Return: The VAR_REF field if it does reference the variable, NULL if not 898 */ 899 static struct hist_field * 900 check_field_for_var_ref(struct hist_field *hist_field, 901 struct hist_trigger_data *var_data, 902 unsigned int var_idx) 903 { 904 WARN_ON(!(hist_field && hist_field->flags & HIST_FIELD_FL_VAR_REF)); 905 906 if (hist_field && hist_field->var.idx == var_idx && 907 hist_field->var.hist_data == var_data) 908 return hist_field; 909 910 return NULL; 911 } 912 913 /** 914 * find_var_ref - Check if a trigger has a reference to a trigger variable 915 * @hist_data: The hist trigger that might have a reference to the variable 916 * @var_data: The hist trigger that owns the variable 917 * @var_idx: The trigger variable identifier 918 * 919 * Check the list of var_refs[] on the first hist trigger to see 920 * whether any of them are references to the variable on the second 921 * trigger. 922 * 923 * Return: The VAR_REF field referencing the variable if so, NULL if not 924 */ 925 static struct hist_field *find_var_ref(struct hist_trigger_data *hist_data, 926 struct hist_trigger_data *var_data, 927 unsigned int var_idx) 928 { 929 struct hist_field *hist_field; 930 unsigned int i; 931 932 for (i = 0; i < hist_data->n_var_refs; i++) { 933 hist_field = hist_data->var_refs[i]; 934 if (check_field_for_var_ref(hist_field, var_data, var_idx)) 935 return hist_field; 936 } 937 938 return NULL; 939 } 940 941 /** 942 * find_any_var_ref - Check if there is a reference to a given trigger variable 943 * @hist_data: The hist trigger 944 * @var_idx: The trigger variable identifier 945 * 946 * Check to see whether the given variable is currently referenced by 947 * any other trigger. 948 * 949 * The trigger the variable is defined on is explicitly excluded - the 950 * assumption being that a self-reference doesn't prevent a trigger 951 * from being removed. 952 * 953 * Return: The VAR_REF field referencing the variable if so, NULL if not 954 */ 955 static struct hist_field *find_any_var_ref(struct hist_trigger_data *hist_data, 956 unsigned int var_idx) 957 { 958 struct trace_array *tr = hist_data->event_file->tr; 959 struct hist_field *found = NULL; 960 struct hist_var_data *var_data; 961 962 list_for_each_entry(var_data, &tr->hist_vars, list) { 963 if (var_data->hist_data == hist_data) 964 continue; 965 found = find_var_ref(var_data->hist_data, hist_data, var_idx); 966 if (found) 967 break; 968 } 969 970 return found; 971 } 972 973 /** 974 * check_var_refs - Check if there is a reference to any of trigger's variables 975 * @hist_data: The hist trigger 976 * 977 * A trigger can define one or more variables. If any one of them is 978 * currently referenced by any other trigger, this function will 979 * determine that. 980 * 981 * Typically used to determine whether or not a trigger can be removed 982 * - if there are any references to a trigger's variables, it cannot. 983 * 984 * Return: True if there is a reference to any of trigger's variables 985 */ 986 static bool check_var_refs(struct hist_trigger_data *hist_data) 987 { 988 struct hist_field *field; 989 bool found = false; 990 int i; 991 992 for_each_hist_field(i, hist_data) { 993 field = hist_data->fields[i]; 994 if (field && field->flags & HIST_FIELD_FL_VAR) { 995 if (find_any_var_ref(hist_data, field->var.idx)) { 996 found = true; 997 break; 998 } 999 } 1000 } 1001 1002 return found; 1003 } 1004 1005 static struct hist_var_data *find_hist_vars(struct hist_trigger_data *hist_data) 1006 { 1007 struct trace_array *tr = hist_data->event_file->tr; 1008 struct hist_var_data *var_data, *found = NULL; 1009 1010 list_for_each_entry(var_data, &tr->hist_vars, list) { 1011 if (var_data->hist_data == hist_data) { 1012 found = var_data; 1013 break; 1014 } 1015 } 1016 1017 return found; 1018 } 1019 1020 static bool field_has_hist_vars(struct hist_field *hist_field, 1021 unsigned int level) 1022 { 1023 int i; 1024 1025 if (level > 3) 1026 return false; 1027 1028 if (!hist_field) 1029 return false; 1030 1031 if (hist_field->flags & HIST_FIELD_FL_VAR || 1032 hist_field->flags & HIST_FIELD_FL_VAR_REF) 1033 return true; 1034 1035 for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++) { 1036 struct hist_field *operand; 1037 1038 operand = hist_field->operands[i]; 1039 if (field_has_hist_vars(operand, level + 1)) 1040 return true; 1041 } 1042 1043 return false; 1044 } 1045 1046 static bool has_hist_vars(struct hist_trigger_data *hist_data) 1047 { 1048 struct hist_field *hist_field; 1049 int i; 1050 1051 for_each_hist_field(i, hist_data) { 1052 hist_field = hist_data->fields[i]; 1053 if (field_has_hist_vars(hist_field, 0)) 1054 return true; 1055 } 1056 1057 return false; 1058 } 1059 1060 static int save_hist_vars(struct hist_trigger_data *hist_data) 1061 { 1062 struct trace_array *tr = hist_data->event_file->tr; 1063 struct hist_var_data *var_data; 1064 1065 var_data = find_hist_vars(hist_data); 1066 if (var_data) 1067 return 0; 1068 1069 if (tracing_check_open_get_tr(tr)) 1070 return -ENODEV; 1071 1072 var_data = kzalloc(sizeof(*var_data), GFP_KERNEL); 1073 if (!var_data) { 1074 trace_array_put(tr); 1075 return -ENOMEM; 1076 } 1077 1078 var_data->hist_data = hist_data; 1079 list_add(&var_data->list, &tr->hist_vars); 1080 1081 return 0; 1082 } 1083 1084 static void remove_hist_vars(struct hist_trigger_data *hist_data) 1085 { 1086 struct trace_array *tr = hist_data->event_file->tr; 1087 struct hist_var_data *var_data; 1088 1089 var_data = find_hist_vars(hist_data); 1090 if (!var_data) 1091 return; 1092 1093 if (WARN_ON(check_var_refs(hist_data))) 1094 return; 1095 1096 list_del(&var_data->list); 1097 1098 kfree(var_data); 1099 1100 trace_array_put(tr); 1101 } 1102 1103 static struct hist_field *find_var_field(struct hist_trigger_data *hist_data, 1104 const char *var_name) 1105 { 1106 struct hist_field *hist_field, *found = NULL; 1107 int i; 1108 1109 for_each_hist_field(i, hist_data) { 1110 hist_field = hist_data->fields[i]; 1111 if (hist_field && hist_field->flags & HIST_FIELD_FL_VAR && 1112 strcmp(hist_field->var.name, var_name) == 0) { 1113 found = hist_field; 1114 break; 1115 } 1116 } 1117 1118 return found; 1119 } 1120 1121 static struct hist_field *find_var(struct hist_trigger_data *hist_data, 1122 struct trace_event_file *file, 1123 const char *var_name) 1124 { 1125 struct hist_trigger_data *test_data; 1126 struct event_trigger_data *test; 1127 struct hist_field *hist_field; 1128 1129 lockdep_assert_held(&event_mutex); 1130 1131 hist_field = find_var_field(hist_data, var_name); 1132 if (hist_field) 1133 return hist_field; 1134 1135 list_for_each_entry(test, &file->triggers, list) { 1136 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 1137 test_data = test->private_data; 1138 hist_field = find_var_field(test_data, var_name); 1139 if (hist_field) 1140 return hist_field; 1141 } 1142 } 1143 1144 return NULL; 1145 } 1146 1147 static struct trace_event_file *find_var_file(struct trace_array *tr, 1148 char *system, 1149 char *event_name, 1150 char *var_name) 1151 { 1152 struct hist_trigger_data *var_hist_data; 1153 struct hist_var_data *var_data; 1154 struct trace_event_file *file, *found = NULL; 1155 1156 if (system) 1157 return find_event_file(tr, system, event_name); 1158 1159 list_for_each_entry(var_data, &tr->hist_vars, list) { 1160 var_hist_data = var_data->hist_data; 1161 file = var_hist_data->event_file; 1162 if (file == found) 1163 continue; 1164 1165 if (find_var_field(var_hist_data, var_name)) { 1166 if (found) { 1167 hist_err(tr, HIST_ERR_VAR_NOT_UNIQUE, errpos(var_name)); 1168 return NULL; 1169 } 1170 1171 found = file; 1172 } 1173 } 1174 1175 return found; 1176 } 1177 1178 static struct hist_field *find_file_var(struct trace_event_file *file, 1179 const char *var_name) 1180 { 1181 struct hist_trigger_data *test_data; 1182 struct event_trigger_data *test; 1183 struct hist_field *hist_field; 1184 1185 lockdep_assert_held(&event_mutex); 1186 1187 list_for_each_entry(test, &file->triggers, list) { 1188 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 1189 test_data = test->private_data; 1190 hist_field = find_var_field(test_data, var_name); 1191 if (hist_field) 1192 return hist_field; 1193 } 1194 } 1195 1196 return NULL; 1197 } 1198 1199 static struct hist_field * 1200 find_match_var(struct hist_trigger_data *hist_data, char *var_name) 1201 { 1202 struct trace_array *tr = hist_data->event_file->tr; 1203 struct hist_field *hist_field, *found = NULL; 1204 struct trace_event_file *file; 1205 unsigned int i; 1206 1207 for (i = 0; i < hist_data->n_actions; i++) { 1208 struct action_data *data = hist_data->actions[i]; 1209 1210 if (data->handler == HANDLER_ONMATCH) { 1211 char *system = data->match_data.event_system; 1212 char *event_name = data->match_data.event; 1213 1214 file = find_var_file(tr, system, event_name, var_name); 1215 if (!file) 1216 continue; 1217 hist_field = find_file_var(file, var_name); 1218 if (hist_field) { 1219 if (found) { 1220 hist_err(tr, HIST_ERR_VAR_NOT_UNIQUE, 1221 errpos(var_name)); 1222 return ERR_PTR(-EINVAL); 1223 } 1224 1225 found = hist_field; 1226 } 1227 } 1228 } 1229 return found; 1230 } 1231 1232 static struct hist_field *find_event_var(struct hist_trigger_data *hist_data, 1233 char *system, 1234 char *event_name, 1235 char *var_name) 1236 { 1237 struct trace_array *tr = hist_data->event_file->tr; 1238 struct hist_field *hist_field = NULL; 1239 struct trace_event_file *file; 1240 1241 if (!system || !event_name) { 1242 hist_field = find_match_var(hist_data, var_name); 1243 if (IS_ERR(hist_field)) 1244 return NULL; 1245 if (hist_field) 1246 return hist_field; 1247 } 1248 1249 file = find_var_file(tr, system, event_name, var_name); 1250 if (!file) 1251 return NULL; 1252 1253 hist_field = find_file_var(file, var_name); 1254 1255 return hist_field; 1256 } 1257 1258 static u64 hist_field_var_ref(struct hist_field *hist_field, 1259 struct tracing_map_elt *elt, 1260 struct trace_buffer *buffer, 1261 struct ring_buffer_event *rbe, 1262 void *event) 1263 { 1264 struct hist_elt_data *elt_data; 1265 u64 var_val = 0; 1266 1267 if (WARN_ON_ONCE(!elt)) 1268 return var_val; 1269 1270 elt_data = elt->private_data; 1271 var_val = elt_data->var_ref_vals[hist_field->var_ref_idx]; 1272 1273 return var_val; 1274 } 1275 1276 static bool resolve_var_refs(struct hist_trigger_data *hist_data, void *key, 1277 u64 *var_ref_vals, bool self) 1278 { 1279 struct hist_trigger_data *var_data; 1280 struct tracing_map_elt *var_elt; 1281 struct hist_field *hist_field; 1282 unsigned int i, var_idx; 1283 bool resolved = true; 1284 u64 var_val = 0; 1285 1286 for (i = 0; i < hist_data->n_var_refs; i++) { 1287 hist_field = hist_data->var_refs[i]; 1288 var_idx = hist_field->var.idx; 1289 var_data = hist_field->var.hist_data; 1290 1291 if (var_data == NULL) { 1292 resolved = false; 1293 break; 1294 } 1295 1296 if ((self && var_data != hist_data) || 1297 (!self && var_data == hist_data)) 1298 continue; 1299 1300 var_elt = tracing_map_lookup(var_data->map, key); 1301 if (!var_elt) { 1302 resolved = false; 1303 break; 1304 } 1305 1306 if (!tracing_map_var_set(var_elt, var_idx)) { 1307 resolved = false; 1308 break; 1309 } 1310 1311 if (self || !hist_field->read_once) 1312 var_val = tracing_map_read_var(var_elt, var_idx); 1313 else 1314 var_val = tracing_map_read_var_once(var_elt, var_idx); 1315 1316 var_ref_vals[i] = var_val; 1317 } 1318 1319 return resolved; 1320 } 1321 1322 static const char *hist_field_name(struct hist_field *field, 1323 unsigned int level) 1324 { 1325 const char *field_name = ""; 1326 1327 if (WARN_ON_ONCE(!field)) 1328 return field_name; 1329 1330 if (level > 1) 1331 return field_name; 1332 1333 if (field->field) 1334 field_name = field->field->name; 1335 else if (field->flags & HIST_FIELD_FL_LOG2 || 1336 field->flags & HIST_FIELD_FL_ALIAS || 1337 field->flags & HIST_FIELD_FL_BUCKET) 1338 field_name = hist_field_name(field->operands[0], ++level); 1339 else if (field->flags & HIST_FIELD_FL_CPU) 1340 field_name = "common_cpu"; 1341 else if (field->flags & HIST_FIELD_FL_EXPR || 1342 field->flags & HIST_FIELD_FL_VAR_REF) { 1343 if (field->system) { 1344 static char full_name[MAX_FILTER_STR_VAL]; 1345 1346 strcat(full_name, field->system); 1347 strcat(full_name, "."); 1348 strcat(full_name, field->event_name); 1349 strcat(full_name, "."); 1350 strcat(full_name, field->name); 1351 field_name = full_name; 1352 } else 1353 field_name = field->name; 1354 } else if (field->flags & HIST_FIELD_FL_TIMESTAMP) 1355 field_name = "common_timestamp"; 1356 else if (field->flags & HIST_FIELD_FL_STACKTRACE) { 1357 if (field->field) 1358 field_name = field->field->name; 1359 else 1360 field_name = "common_stacktrace"; 1361 } else if (field->flags & HIST_FIELD_FL_HITCOUNT) 1362 field_name = "hitcount"; 1363 1364 if (field_name == NULL) 1365 field_name = ""; 1366 1367 return field_name; 1368 } 1369 1370 static enum hist_field_fn select_value_fn(int field_size, int field_is_signed) 1371 { 1372 switch (field_size) { 1373 case 8: 1374 if (field_is_signed) 1375 return HIST_FIELD_FN_S64; 1376 else 1377 return HIST_FIELD_FN_U64; 1378 case 4: 1379 if (field_is_signed) 1380 return HIST_FIELD_FN_S32; 1381 else 1382 return HIST_FIELD_FN_U32; 1383 case 2: 1384 if (field_is_signed) 1385 return HIST_FIELD_FN_S16; 1386 else 1387 return HIST_FIELD_FN_U16; 1388 case 1: 1389 if (field_is_signed) 1390 return HIST_FIELD_FN_S8; 1391 else 1392 return HIST_FIELD_FN_U8; 1393 } 1394 1395 return HIST_FIELD_FN_NOP; 1396 } 1397 1398 static int parse_map_size(char *str) 1399 { 1400 unsigned long size, map_bits; 1401 int ret; 1402 1403 ret = kstrtoul(str, 0, &size); 1404 if (ret) 1405 goto out; 1406 1407 map_bits = ilog2(roundup_pow_of_two(size)); 1408 if (map_bits < TRACING_MAP_BITS_MIN || 1409 map_bits > TRACING_MAP_BITS_MAX) 1410 ret = -EINVAL; 1411 else 1412 ret = map_bits; 1413 out: 1414 return ret; 1415 } 1416 1417 static void destroy_hist_trigger_attrs(struct hist_trigger_attrs *attrs) 1418 { 1419 unsigned int i; 1420 1421 if (!attrs) 1422 return; 1423 1424 for (i = 0; i < attrs->n_assignments; i++) 1425 kfree(attrs->assignment_str[i]); 1426 1427 for (i = 0; i < attrs->n_actions; i++) 1428 kfree(attrs->action_str[i]); 1429 1430 kfree(attrs->name); 1431 kfree(attrs->sort_key_str); 1432 kfree(attrs->keys_str); 1433 kfree(attrs->vals_str); 1434 kfree(attrs->clock); 1435 kfree(attrs); 1436 } 1437 1438 static int parse_action(char *str, struct hist_trigger_attrs *attrs) 1439 { 1440 int ret = -EINVAL; 1441 1442 if (attrs->n_actions >= HIST_ACTIONS_MAX) 1443 return ret; 1444 1445 if ((str_has_prefix(str, "onmatch(")) || 1446 (str_has_prefix(str, "onmax(")) || 1447 (str_has_prefix(str, "onchange("))) { 1448 attrs->action_str[attrs->n_actions] = kstrdup(str, GFP_KERNEL); 1449 if (!attrs->action_str[attrs->n_actions]) { 1450 ret = -ENOMEM; 1451 return ret; 1452 } 1453 attrs->n_actions++; 1454 ret = 0; 1455 } 1456 return ret; 1457 } 1458 1459 static int parse_assignment(struct trace_array *tr, 1460 char *str, struct hist_trigger_attrs *attrs) 1461 { 1462 int len, ret = 0; 1463 1464 if ((len = str_has_prefix(str, "key=")) || 1465 (len = str_has_prefix(str, "keys="))) { 1466 attrs->keys_str = kstrdup(str + len, GFP_KERNEL); 1467 if (!attrs->keys_str) { 1468 ret = -ENOMEM; 1469 goto out; 1470 } 1471 } else if ((len = str_has_prefix(str, "val=")) || 1472 (len = str_has_prefix(str, "vals=")) || 1473 (len = str_has_prefix(str, "values="))) { 1474 attrs->vals_str = kstrdup(str + len, GFP_KERNEL); 1475 if (!attrs->vals_str) { 1476 ret = -ENOMEM; 1477 goto out; 1478 } 1479 } else if ((len = str_has_prefix(str, "sort="))) { 1480 attrs->sort_key_str = kstrdup(str + len, GFP_KERNEL); 1481 if (!attrs->sort_key_str) { 1482 ret = -ENOMEM; 1483 goto out; 1484 } 1485 } else if (str_has_prefix(str, "name=")) { 1486 attrs->name = kstrdup(str, GFP_KERNEL); 1487 if (!attrs->name) { 1488 ret = -ENOMEM; 1489 goto out; 1490 } 1491 } else if ((len = str_has_prefix(str, "clock="))) { 1492 str += len; 1493 1494 str = strstrip(str); 1495 attrs->clock = kstrdup(str, GFP_KERNEL); 1496 if (!attrs->clock) { 1497 ret = -ENOMEM; 1498 goto out; 1499 } 1500 } else if ((len = str_has_prefix(str, "size="))) { 1501 int map_bits = parse_map_size(str + len); 1502 1503 if (map_bits < 0) { 1504 ret = map_bits; 1505 goto out; 1506 } 1507 attrs->map_bits = map_bits; 1508 } else { 1509 char *assignment; 1510 1511 if (attrs->n_assignments == TRACING_MAP_VARS_MAX) { 1512 hist_err(tr, HIST_ERR_TOO_MANY_VARS, errpos(str)); 1513 ret = -EINVAL; 1514 goto out; 1515 } 1516 1517 assignment = kstrdup(str, GFP_KERNEL); 1518 if (!assignment) { 1519 ret = -ENOMEM; 1520 goto out; 1521 } 1522 1523 attrs->assignment_str[attrs->n_assignments++] = assignment; 1524 } 1525 out: 1526 return ret; 1527 } 1528 1529 static struct hist_trigger_attrs * 1530 parse_hist_trigger_attrs(struct trace_array *tr, char *trigger_str) 1531 { 1532 struct hist_trigger_attrs *attrs; 1533 int ret = 0; 1534 1535 attrs = kzalloc(sizeof(*attrs), GFP_KERNEL); 1536 if (!attrs) 1537 return ERR_PTR(-ENOMEM); 1538 1539 while (trigger_str) { 1540 char *str = strsep(&trigger_str, ":"); 1541 char *rhs; 1542 1543 rhs = strchr(str, '='); 1544 if (rhs) { 1545 if (!strlen(++rhs)) { 1546 ret = -EINVAL; 1547 hist_err(tr, HIST_ERR_EMPTY_ASSIGNMENT, errpos(str)); 1548 goto free; 1549 } 1550 ret = parse_assignment(tr, str, attrs); 1551 if (ret) 1552 goto free; 1553 } else if (strcmp(str, "nohitcount") == 0 || 1554 strcmp(str, "NOHC") == 0) 1555 attrs->no_hitcount = true; 1556 else if (strcmp(str, "pause") == 0) 1557 attrs->pause = true; 1558 else if ((strcmp(str, "cont") == 0) || 1559 (strcmp(str, "continue") == 0)) 1560 attrs->cont = true; 1561 else if (strcmp(str, "clear") == 0) 1562 attrs->clear = true; 1563 else { 1564 ret = parse_action(str, attrs); 1565 if (ret) 1566 goto free; 1567 } 1568 } 1569 1570 if (!attrs->keys_str) { 1571 ret = -EINVAL; 1572 goto free; 1573 } 1574 1575 if (!attrs->clock) { 1576 attrs->clock = kstrdup("global", GFP_KERNEL); 1577 if (!attrs->clock) { 1578 ret = -ENOMEM; 1579 goto free; 1580 } 1581 } 1582 1583 return attrs; 1584 free: 1585 destroy_hist_trigger_attrs(attrs); 1586 1587 return ERR_PTR(ret); 1588 } 1589 1590 static inline void save_comm(char *comm, struct task_struct *task) 1591 { 1592 if (!task->pid) { 1593 strcpy(comm, "<idle>"); 1594 return; 1595 } 1596 1597 if (WARN_ON_ONCE(task->pid < 0)) { 1598 strcpy(comm, "<XXX>"); 1599 return; 1600 } 1601 1602 strncpy(comm, task->comm, TASK_COMM_LEN); 1603 } 1604 1605 static void hist_elt_data_free(struct hist_elt_data *elt_data) 1606 { 1607 unsigned int i; 1608 1609 for (i = 0; i < elt_data->n_field_var_str; i++) 1610 kfree(elt_data->field_var_str[i]); 1611 1612 kfree(elt_data->field_var_str); 1613 1614 kfree(elt_data->comm); 1615 kfree(elt_data); 1616 } 1617 1618 static void hist_trigger_elt_data_free(struct tracing_map_elt *elt) 1619 { 1620 struct hist_elt_data *elt_data = elt->private_data; 1621 1622 hist_elt_data_free(elt_data); 1623 } 1624 1625 static int hist_trigger_elt_data_alloc(struct tracing_map_elt *elt) 1626 { 1627 struct hist_trigger_data *hist_data = elt->map->private_data; 1628 unsigned int size = TASK_COMM_LEN; 1629 struct hist_elt_data *elt_data; 1630 struct hist_field *hist_field; 1631 unsigned int i, n_str; 1632 1633 elt_data = kzalloc(sizeof(*elt_data), GFP_KERNEL); 1634 if (!elt_data) 1635 return -ENOMEM; 1636 1637 for_each_hist_field(i, hist_data) { 1638 hist_field = hist_data->fields[i]; 1639 1640 if (hist_field->flags & HIST_FIELD_FL_EXECNAME) { 1641 elt_data->comm = kzalloc(size, GFP_KERNEL); 1642 if (!elt_data->comm) { 1643 kfree(elt_data); 1644 return -ENOMEM; 1645 } 1646 break; 1647 } 1648 } 1649 1650 n_str = hist_data->n_field_var_str + hist_data->n_save_var_str + 1651 hist_data->n_var_str; 1652 if (n_str > SYNTH_FIELDS_MAX) { 1653 hist_elt_data_free(elt_data); 1654 return -EINVAL; 1655 } 1656 1657 BUILD_BUG_ON(STR_VAR_LEN_MAX & (sizeof(u64) - 1)); 1658 1659 size = STR_VAR_LEN_MAX; 1660 1661 elt_data->field_var_str = kcalloc(n_str, sizeof(char *), GFP_KERNEL); 1662 if (!elt_data->field_var_str) { 1663 hist_elt_data_free(elt_data); 1664 return -EINVAL; 1665 } 1666 elt_data->n_field_var_str = n_str; 1667 1668 for (i = 0; i < n_str; i++) { 1669 elt_data->field_var_str[i] = kzalloc(size, GFP_KERNEL); 1670 if (!elt_data->field_var_str[i]) { 1671 hist_elt_data_free(elt_data); 1672 return -ENOMEM; 1673 } 1674 } 1675 1676 elt->private_data = elt_data; 1677 1678 return 0; 1679 } 1680 1681 static void hist_trigger_elt_data_init(struct tracing_map_elt *elt) 1682 { 1683 struct hist_elt_data *elt_data = elt->private_data; 1684 1685 if (elt_data->comm) 1686 save_comm(elt_data->comm, current); 1687 } 1688 1689 static const struct tracing_map_ops hist_trigger_elt_data_ops = { 1690 .elt_alloc = hist_trigger_elt_data_alloc, 1691 .elt_free = hist_trigger_elt_data_free, 1692 .elt_init = hist_trigger_elt_data_init, 1693 }; 1694 1695 static const char *get_hist_field_flags(struct hist_field *hist_field) 1696 { 1697 const char *flags_str = NULL; 1698 1699 if (hist_field->flags & HIST_FIELD_FL_HEX) 1700 flags_str = "hex"; 1701 else if (hist_field->flags & HIST_FIELD_FL_SYM) 1702 flags_str = "sym"; 1703 else if (hist_field->flags & HIST_FIELD_FL_SYM_OFFSET) 1704 flags_str = "sym-offset"; 1705 else if (hist_field->flags & HIST_FIELD_FL_EXECNAME) 1706 flags_str = "execname"; 1707 else if (hist_field->flags & HIST_FIELD_FL_SYSCALL) 1708 flags_str = "syscall"; 1709 else if (hist_field->flags & HIST_FIELD_FL_LOG2) 1710 flags_str = "log2"; 1711 else if (hist_field->flags & HIST_FIELD_FL_BUCKET) 1712 flags_str = "buckets"; 1713 else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP_USECS) 1714 flags_str = "usecs"; 1715 else if (hist_field->flags & HIST_FIELD_FL_PERCENT) 1716 flags_str = "percent"; 1717 else if (hist_field->flags & HIST_FIELD_FL_GRAPH) 1718 flags_str = "graph"; 1719 else if (hist_field->flags & HIST_FIELD_FL_STACKTRACE) 1720 flags_str = "stacktrace"; 1721 1722 return flags_str; 1723 } 1724 1725 static void expr_field_str(struct hist_field *field, char *expr) 1726 { 1727 if (field->flags & HIST_FIELD_FL_VAR_REF) 1728 strcat(expr, "$"); 1729 else if (field->flags & HIST_FIELD_FL_CONST) { 1730 char str[HIST_CONST_DIGITS_MAX]; 1731 1732 snprintf(str, HIST_CONST_DIGITS_MAX, "%llu", field->constant); 1733 strcat(expr, str); 1734 } 1735 1736 strcat(expr, hist_field_name(field, 0)); 1737 1738 if (field->flags && !(field->flags & HIST_FIELD_FL_VAR_REF)) { 1739 const char *flags_str = get_hist_field_flags(field); 1740 1741 if (flags_str) { 1742 strcat(expr, "."); 1743 strcat(expr, flags_str); 1744 } 1745 } 1746 } 1747 1748 static char *expr_str(struct hist_field *field, unsigned int level) 1749 { 1750 char *expr; 1751 1752 if (level > 1) 1753 return NULL; 1754 1755 expr = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL); 1756 if (!expr) 1757 return NULL; 1758 1759 if (!field->operands[0]) { 1760 expr_field_str(field, expr); 1761 return expr; 1762 } 1763 1764 if (field->operator == FIELD_OP_UNARY_MINUS) { 1765 char *subexpr; 1766 1767 strcat(expr, "-("); 1768 subexpr = expr_str(field->operands[0], ++level); 1769 if (!subexpr) { 1770 kfree(expr); 1771 return NULL; 1772 } 1773 strcat(expr, subexpr); 1774 strcat(expr, ")"); 1775 1776 kfree(subexpr); 1777 1778 return expr; 1779 } 1780 1781 expr_field_str(field->operands[0], expr); 1782 1783 switch (field->operator) { 1784 case FIELD_OP_MINUS: 1785 strcat(expr, "-"); 1786 break; 1787 case FIELD_OP_PLUS: 1788 strcat(expr, "+"); 1789 break; 1790 case FIELD_OP_DIV: 1791 strcat(expr, "/"); 1792 break; 1793 case FIELD_OP_MULT: 1794 strcat(expr, "*"); 1795 break; 1796 default: 1797 kfree(expr); 1798 return NULL; 1799 } 1800 1801 expr_field_str(field->operands[1], expr); 1802 1803 return expr; 1804 } 1805 1806 /* 1807 * If field_op != FIELD_OP_NONE, *sep points to the root operator 1808 * of the expression tree to be evaluated. 1809 */ 1810 static int contains_operator(char *str, char **sep) 1811 { 1812 enum field_op_id field_op = FIELD_OP_NONE; 1813 char *minus_op, *plus_op, *div_op, *mult_op; 1814 1815 1816 /* 1817 * Report the last occurrence of the operators first, so that the 1818 * expression is evaluated left to right. This is important since 1819 * subtraction and division are not associative. 1820 * 1821 * e.g 1822 * 64/8/4/2 is 1, i.e 64/8/4/2 = ((64/8)/4)/2 1823 * 14-7-5-2 is 0, i.e 14-7-5-2 = ((14-7)-5)-2 1824 */ 1825 1826 /* 1827 * First, find lower precedence addition and subtraction 1828 * since the expression will be evaluated recursively. 1829 */ 1830 minus_op = strrchr(str, '-'); 1831 if (minus_op) { 1832 /* 1833 * Unary minus is not supported in sub-expressions. If 1834 * present, it is always the next root operator. 1835 */ 1836 if (minus_op == str) { 1837 field_op = FIELD_OP_UNARY_MINUS; 1838 goto out; 1839 } 1840 1841 field_op = FIELD_OP_MINUS; 1842 } 1843 1844 plus_op = strrchr(str, '+'); 1845 if (plus_op || minus_op) { 1846 /* 1847 * For operators of the same precedence use to rightmost as the 1848 * root, so that the expression is evaluated left to right. 1849 */ 1850 if (plus_op > minus_op) 1851 field_op = FIELD_OP_PLUS; 1852 goto out; 1853 } 1854 1855 /* 1856 * Multiplication and division have higher precedence than addition and 1857 * subtraction. 1858 */ 1859 div_op = strrchr(str, '/'); 1860 if (div_op) 1861 field_op = FIELD_OP_DIV; 1862 1863 mult_op = strrchr(str, '*'); 1864 /* 1865 * For operators of the same precedence use to rightmost as the 1866 * root, so that the expression is evaluated left to right. 1867 */ 1868 if (mult_op > div_op) 1869 field_op = FIELD_OP_MULT; 1870 1871 out: 1872 if (sep) { 1873 switch (field_op) { 1874 case FIELD_OP_UNARY_MINUS: 1875 case FIELD_OP_MINUS: 1876 *sep = minus_op; 1877 break; 1878 case FIELD_OP_PLUS: 1879 *sep = plus_op; 1880 break; 1881 case FIELD_OP_DIV: 1882 *sep = div_op; 1883 break; 1884 case FIELD_OP_MULT: 1885 *sep = mult_op; 1886 break; 1887 case FIELD_OP_NONE: 1888 default: 1889 *sep = NULL; 1890 break; 1891 } 1892 } 1893 1894 return field_op; 1895 } 1896 1897 static void get_hist_field(struct hist_field *hist_field) 1898 { 1899 hist_field->ref++; 1900 } 1901 1902 static void __destroy_hist_field(struct hist_field *hist_field) 1903 { 1904 if (--hist_field->ref > 1) 1905 return; 1906 1907 kfree(hist_field->var.name); 1908 kfree(hist_field->name); 1909 1910 /* Can likely be a const */ 1911 kfree_const(hist_field->type); 1912 1913 kfree(hist_field->system); 1914 kfree(hist_field->event_name); 1915 1916 kfree(hist_field); 1917 } 1918 1919 static void destroy_hist_field(struct hist_field *hist_field, 1920 unsigned int level) 1921 { 1922 unsigned int i; 1923 1924 if (level > 3) 1925 return; 1926 1927 if (!hist_field) 1928 return; 1929 1930 if (hist_field->flags & HIST_FIELD_FL_VAR_REF) 1931 return; /* var refs will be destroyed separately */ 1932 1933 for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++) 1934 destroy_hist_field(hist_field->operands[i], level + 1); 1935 1936 __destroy_hist_field(hist_field); 1937 } 1938 1939 static struct hist_field *create_hist_field(struct hist_trigger_data *hist_data, 1940 struct ftrace_event_field *field, 1941 unsigned long flags, 1942 char *var_name) 1943 { 1944 struct hist_field *hist_field; 1945 1946 if (field && is_function_field(field)) 1947 return NULL; 1948 1949 hist_field = kzalloc(sizeof(struct hist_field), GFP_KERNEL); 1950 if (!hist_field) 1951 return NULL; 1952 1953 hist_field->ref = 1; 1954 1955 hist_field->hist_data = hist_data; 1956 1957 if (flags & HIST_FIELD_FL_EXPR || flags & HIST_FIELD_FL_ALIAS) 1958 goto out; /* caller will populate */ 1959 1960 if (flags & HIST_FIELD_FL_VAR_REF) { 1961 hist_field->fn_num = HIST_FIELD_FN_VAR_REF; 1962 goto out; 1963 } 1964 1965 if (flags & HIST_FIELD_FL_HITCOUNT) { 1966 hist_field->fn_num = HIST_FIELD_FN_COUNTER; 1967 hist_field->size = sizeof(u64); 1968 hist_field->type = "u64"; 1969 goto out; 1970 } 1971 1972 if (flags & HIST_FIELD_FL_CONST) { 1973 hist_field->fn_num = HIST_FIELD_FN_CONST; 1974 hist_field->size = sizeof(u64); 1975 hist_field->type = kstrdup("u64", GFP_KERNEL); 1976 if (!hist_field->type) 1977 goto free; 1978 goto out; 1979 } 1980 1981 if (flags & HIST_FIELD_FL_STACKTRACE) { 1982 if (field) 1983 hist_field->fn_num = HIST_FIELD_FN_STACK; 1984 else 1985 hist_field->fn_num = HIST_FIELD_FN_NOP; 1986 hist_field->size = HIST_STACKTRACE_SIZE; 1987 hist_field->type = kstrdup_const("unsigned long[]", GFP_KERNEL); 1988 if (!hist_field->type) 1989 goto free; 1990 goto out; 1991 } 1992 1993 if (flags & (HIST_FIELD_FL_LOG2 | HIST_FIELD_FL_BUCKET)) { 1994 unsigned long fl = flags & ~(HIST_FIELD_FL_LOG2 | HIST_FIELD_FL_BUCKET); 1995 hist_field->fn_num = flags & HIST_FIELD_FL_LOG2 ? HIST_FIELD_FN_LOG2 : 1996 HIST_FIELD_FN_BUCKET; 1997 hist_field->operands[0] = create_hist_field(hist_data, field, fl, NULL); 1998 if (!hist_field->operands[0]) 1999 goto free; 2000 hist_field->size = hist_field->operands[0]->size; 2001 hist_field->type = kstrdup_const(hist_field->operands[0]->type, GFP_KERNEL); 2002 if (!hist_field->type) 2003 goto free; 2004 goto out; 2005 } 2006 2007 if (flags & HIST_FIELD_FL_TIMESTAMP) { 2008 hist_field->fn_num = HIST_FIELD_FN_TIMESTAMP; 2009 hist_field->size = sizeof(u64); 2010 hist_field->type = "u64"; 2011 goto out; 2012 } 2013 2014 if (flags & HIST_FIELD_FL_CPU) { 2015 hist_field->fn_num = HIST_FIELD_FN_CPU; 2016 hist_field->size = sizeof(int); 2017 hist_field->type = "unsigned int"; 2018 goto out; 2019 } 2020 2021 if (WARN_ON_ONCE(!field)) 2022 goto out; 2023 2024 /* Pointers to strings are just pointers and dangerous to dereference */ 2025 if (is_string_field(field) && 2026 (field->filter_type != FILTER_PTR_STRING)) { 2027 flags |= HIST_FIELD_FL_STRING; 2028 2029 hist_field->size = MAX_FILTER_STR_VAL; 2030 hist_field->type = kstrdup_const(field->type, GFP_KERNEL); 2031 if (!hist_field->type) 2032 goto free; 2033 2034 if (field->filter_type == FILTER_STATIC_STRING) { 2035 hist_field->fn_num = HIST_FIELD_FN_STRING; 2036 hist_field->size = field->size; 2037 } else if (field->filter_type == FILTER_DYN_STRING) { 2038 hist_field->fn_num = HIST_FIELD_FN_DYNSTRING; 2039 } else if (field->filter_type == FILTER_RDYN_STRING) 2040 hist_field->fn_num = HIST_FIELD_FN_RELDYNSTRING; 2041 else 2042 hist_field->fn_num = HIST_FIELD_FN_PSTRING; 2043 } else { 2044 hist_field->size = field->size; 2045 hist_field->is_signed = field->is_signed; 2046 hist_field->type = kstrdup_const(field->type, GFP_KERNEL); 2047 if (!hist_field->type) 2048 goto free; 2049 2050 hist_field->fn_num = select_value_fn(field->size, 2051 field->is_signed); 2052 if (hist_field->fn_num == HIST_FIELD_FN_NOP) { 2053 destroy_hist_field(hist_field, 0); 2054 return NULL; 2055 } 2056 } 2057 out: 2058 hist_field->field = field; 2059 hist_field->flags = flags; 2060 2061 if (var_name) { 2062 hist_field->var.name = kstrdup(var_name, GFP_KERNEL); 2063 if (!hist_field->var.name) 2064 goto free; 2065 } 2066 2067 return hist_field; 2068 free: 2069 destroy_hist_field(hist_field, 0); 2070 return NULL; 2071 } 2072 2073 static void destroy_hist_fields(struct hist_trigger_data *hist_data) 2074 { 2075 unsigned int i; 2076 2077 for (i = 0; i < HIST_FIELDS_MAX; i++) { 2078 if (hist_data->fields[i]) { 2079 destroy_hist_field(hist_data->fields[i], 0); 2080 hist_data->fields[i] = NULL; 2081 } 2082 } 2083 2084 for (i = 0; i < hist_data->n_var_refs; i++) { 2085 WARN_ON(!(hist_data->var_refs[i]->flags & HIST_FIELD_FL_VAR_REF)); 2086 __destroy_hist_field(hist_data->var_refs[i]); 2087 hist_data->var_refs[i] = NULL; 2088 } 2089 } 2090 2091 static int init_var_ref(struct hist_field *ref_field, 2092 struct hist_field *var_field, 2093 char *system, char *event_name) 2094 { 2095 int err = 0; 2096 2097 ref_field->var.idx = var_field->var.idx; 2098 ref_field->var.hist_data = var_field->hist_data; 2099 ref_field->size = var_field->size; 2100 ref_field->is_signed = var_field->is_signed; 2101 ref_field->flags |= var_field->flags & 2102 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS); 2103 2104 if (system) { 2105 ref_field->system = kstrdup(system, GFP_KERNEL); 2106 if (!ref_field->system) 2107 return -ENOMEM; 2108 } 2109 2110 if (event_name) { 2111 ref_field->event_name = kstrdup(event_name, GFP_KERNEL); 2112 if (!ref_field->event_name) { 2113 err = -ENOMEM; 2114 goto free; 2115 } 2116 } 2117 2118 if (var_field->var.name) { 2119 ref_field->name = kstrdup(var_field->var.name, GFP_KERNEL); 2120 if (!ref_field->name) { 2121 err = -ENOMEM; 2122 goto free; 2123 } 2124 } else if (var_field->name) { 2125 ref_field->name = kstrdup(var_field->name, GFP_KERNEL); 2126 if (!ref_field->name) { 2127 err = -ENOMEM; 2128 goto free; 2129 } 2130 } 2131 2132 ref_field->type = kstrdup_const(var_field->type, GFP_KERNEL); 2133 if (!ref_field->type) { 2134 err = -ENOMEM; 2135 goto free; 2136 } 2137 out: 2138 return err; 2139 free: 2140 kfree(ref_field->system); 2141 ref_field->system = NULL; 2142 kfree(ref_field->event_name); 2143 ref_field->event_name = NULL; 2144 kfree(ref_field->name); 2145 ref_field->name = NULL; 2146 2147 goto out; 2148 } 2149 2150 static int find_var_ref_idx(struct hist_trigger_data *hist_data, 2151 struct hist_field *var_field) 2152 { 2153 struct hist_field *ref_field; 2154 int i; 2155 2156 for (i = 0; i < hist_data->n_var_refs; i++) { 2157 ref_field = hist_data->var_refs[i]; 2158 if (ref_field->var.idx == var_field->var.idx && 2159 ref_field->var.hist_data == var_field->hist_data) 2160 return i; 2161 } 2162 2163 return -ENOENT; 2164 } 2165 2166 /** 2167 * create_var_ref - Create a variable reference and attach it to trigger 2168 * @hist_data: The trigger that will be referencing the variable 2169 * @var_field: The VAR field to create a reference to 2170 * @system: The optional system string 2171 * @event_name: The optional event_name string 2172 * 2173 * Given a variable hist_field, create a VAR_REF hist_field that 2174 * represents a reference to it. 2175 * 2176 * This function also adds the reference to the trigger that 2177 * now references the variable. 2178 * 2179 * Return: The VAR_REF field if successful, NULL if not 2180 */ 2181 static struct hist_field *create_var_ref(struct hist_trigger_data *hist_data, 2182 struct hist_field *var_field, 2183 char *system, char *event_name) 2184 { 2185 unsigned long flags = HIST_FIELD_FL_VAR_REF; 2186 struct hist_field *ref_field; 2187 int i; 2188 2189 /* Check if the variable already exists */ 2190 for (i = 0; i < hist_data->n_var_refs; i++) { 2191 ref_field = hist_data->var_refs[i]; 2192 if (ref_field->var.idx == var_field->var.idx && 2193 ref_field->var.hist_data == var_field->hist_data) { 2194 get_hist_field(ref_field); 2195 return ref_field; 2196 } 2197 } 2198 /* Sanity check to avoid out-of-bound write on 'hist_data->var_refs' */ 2199 if (hist_data->n_var_refs >= TRACING_MAP_VARS_MAX) 2200 return NULL; 2201 ref_field = create_hist_field(var_field->hist_data, NULL, flags, NULL); 2202 if (ref_field) { 2203 if (init_var_ref(ref_field, var_field, system, event_name)) { 2204 destroy_hist_field(ref_field, 0); 2205 return NULL; 2206 } 2207 2208 hist_data->var_refs[hist_data->n_var_refs] = ref_field; 2209 ref_field->var_ref_idx = hist_data->n_var_refs++; 2210 } 2211 2212 return ref_field; 2213 } 2214 2215 static bool is_var_ref(char *var_name) 2216 { 2217 if (!var_name || strlen(var_name) < 2 || var_name[0] != '$') 2218 return false; 2219 2220 return true; 2221 } 2222 2223 static char *field_name_from_var(struct hist_trigger_data *hist_data, 2224 char *var_name) 2225 { 2226 char *name, *field; 2227 unsigned int i; 2228 2229 for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) { 2230 name = hist_data->attrs->var_defs.name[i]; 2231 2232 if (strcmp(var_name, name) == 0) { 2233 field = hist_data->attrs->var_defs.expr[i]; 2234 if (contains_operator(field, NULL) || is_var_ref(field)) 2235 continue; 2236 return field; 2237 } 2238 } 2239 2240 return NULL; 2241 } 2242 2243 static char *local_field_var_ref(struct hist_trigger_data *hist_data, 2244 char *system, char *event_name, 2245 char *var_name) 2246 { 2247 struct trace_event_call *call; 2248 2249 if (system && event_name) { 2250 call = hist_data->event_file->event_call; 2251 2252 if (strcmp(system, call->class->system) != 0) 2253 return NULL; 2254 2255 if (strcmp(event_name, trace_event_name(call)) != 0) 2256 return NULL; 2257 } 2258 2259 if (!!system != !!event_name) 2260 return NULL; 2261 2262 if (!is_var_ref(var_name)) 2263 return NULL; 2264 2265 var_name++; 2266 2267 return field_name_from_var(hist_data, var_name); 2268 } 2269 2270 static struct hist_field *parse_var_ref(struct hist_trigger_data *hist_data, 2271 char *system, char *event_name, 2272 char *var_name) 2273 { 2274 struct hist_field *var_field = NULL, *ref_field = NULL; 2275 struct trace_array *tr = hist_data->event_file->tr; 2276 2277 if (!is_var_ref(var_name)) 2278 return NULL; 2279 2280 var_name++; 2281 2282 var_field = find_event_var(hist_data, system, event_name, var_name); 2283 if (var_field) 2284 ref_field = create_var_ref(hist_data, var_field, 2285 system, event_name); 2286 2287 if (!ref_field) 2288 hist_err(tr, HIST_ERR_VAR_NOT_FOUND, errpos(var_name)); 2289 2290 return ref_field; 2291 } 2292 2293 static struct ftrace_event_field * 2294 parse_field(struct hist_trigger_data *hist_data, struct trace_event_file *file, 2295 char *field_str, unsigned long *flags, unsigned long *buckets) 2296 { 2297 struct ftrace_event_field *field = NULL; 2298 char *field_name, *modifier, *str; 2299 struct trace_array *tr = file->tr; 2300 2301 modifier = str = kstrdup(field_str, GFP_KERNEL); 2302 if (!modifier) 2303 return ERR_PTR(-ENOMEM); 2304 2305 field_name = strsep(&modifier, "."); 2306 if (modifier) { 2307 if (strcmp(modifier, "hex") == 0) 2308 *flags |= HIST_FIELD_FL_HEX; 2309 else if (strcmp(modifier, "sym") == 0) 2310 *flags |= HIST_FIELD_FL_SYM; 2311 /* 2312 * 'sym-offset' occurrences in the trigger string are modified 2313 * to 'symXoffset' to simplify arithmetic expression parsing. 2314 */ 2315 else if (strcmp(modifier, "symXoffset") == 0) 2316 *flags |= HIST_FIELD_FL_SYM_OFFSET; 2317 else if ((strcmp(modifier, "execname") == 0) && 2318 (strcmp(field_name, "common_pid") == 0)) 2319 *flags |= HIST_FIELD_FL_EXECNAME; 2320 else if (strcmp(modifier, "syscall") == 0) 2321 *flags |= HIST_FIELD_FL_SYSCALL; 2322 else if (strcmp(modifier, "stacktrace") == 0) 2323 *flags |= HIST_FIELD_FL_STACKTRACE; 2324 else if (strcmp(modifier, "log2") == 0) 2325 *flags |= HIST_FIELD_FL_LOG2; 2326 else if (strcmp(modifier, "usecs") == 0) 2327 *flags |= HIST_FIELD_FL_TIMESTAMP_USECS; 2328 else if (strncmp(modifier, "bucket", 6) == 0) { 2329 int ret; 2330 2331 modifier += 6; 2332 2333 if (*modifier == 's') 2334 modifier++; 2335 if (*modifier != '=') 2336 goto error; 2337 modifier++; 2338 ret = kstrtoul(modifier, 0, buckets); 2339 if (ret || !(*buckets)) 2340 goto error; 2341 *flags |= HIST_FIELD_FL_BUCKET; 2342 } else if (strncmp(modifier, "percent", 7) == 0) { 2343 if (*flags & (HIST_FIELD_FL_VAR | HIST_FIELD_FL_KEY)) 2344 goto error; 2345 *flags |= HIST_FIELD_FL_PERCENT; 2346 } else if (strncmp(modifier, "graph", 5) == 0) { 2347 if (*flags & (HIST_FIELD_FL_VAR | HIST_FIELD_FL_KEY)) 2348 goto error; 2349 *flags |= HIST_FIELD_FL_GRAPH; 2350 } else { 2351 error: 2352 hist_err(tr, HIST_ERR_BAD_FIELD_MODIFIER, errpos(modifier)); 2353 field = ERR_PTR(-EINVAL); 2354 goto out; 2355 } 2356 } 2357 2358 if (strcmp(field_name, "common_timestamp") == 0) { 2359 *flags |= HIST_FIELD_FL_TIMESTAMP; 2360 hist_data->enable_timestamps = true; 2361 if (*flags & HIST_FIELD_FL_TIMESTAMP_USECS) 2362 hist_data->attrs->ts_in_usecs = true; 2363 } else if (strcmp(field_name, "common_stacktrace") == 0) { 2364 *flags |= HIST_FIELD_FL_STACKTRACE; 2365 } else if (strcmp(field_name, "common_cpu") == 0) 2366 *flags |= HIST_FIELD_FL_CPU; 2367 else if (strcmp(field_name, "hitcount") == 0) 2368 *flags |= HIST_FIELD_FL_HITCOUNT; 2369 else { 2370 field = trace_find_event_field(file->event_call, field_name); 2371 if (!field || !field->size) { 2372 /* 2373 * For backward compatibility, if field_name 2374 * was "cpu" or "stacktrace", then we treat this 2375 * the same as common_cpu and common_stacktrace 2376 * respectively. This also works for "CPU", and 2377 * "STACKTRACE". 2378 */ 2379 if (field && field->filter_type == FILTER_CPU) { 2380 *flags |= HIST_FIELD_FL_CPU; 2381 } else if (field && field->filter_type == FILTER_STACKTRACE) { 2382 *flags |= HIST_FIELD_FL_STACKTRACE; 2383 } else { 2384 hist_err(tr, HIST_ERR_FIELD_NOT_FOUND, 2385 errpos(field_name)); 2386 field = ERR_PTR(-EINVAL); 2387 goto out; 2388 } 2389 } 2390 } 2391 out: 2392 kfree(str); 2393 2394 return field; 2395 } 2396 2397 static struct hist_field *create_alias(struct hist_trigger_data *hist_data, 2398 struct hist_field *var_ref, 2399 char *var_name) 2400 { 2401 struct hist_field *alias = NULL; 2402 unsigned long flags = HIST_FIELD_FL_ALIAS | HIST_FIELD_FL_VAR; 2403 2404 alias = create_hist_field(hist_data, NULL, flags, var_name); 2405 if (!alias) 2406 return NULL; 2407 2408 alias->fn_num = var_ref->fn_num; 2409 alias->operands[0] = var_ref; 2410 2411 if (init_var_ref(alias, var_ref, var_ref->system, var_ref->event_name)) { 2412 destroy_hist_field(alias, 0); 2413 return NULL; 2414 } 2415 2416 alias->var_ref_idx = var_ref->var_ref_idx; 2417 2418 return alias; 2419 } 2420 2421 static struct hist_field *parse_const(struct hist_trigger_data *hist_data, 2422 char *str, char *var_name, 2423 unsigned long *flags) 2424 { 2425 struct trace_array *tr = hist_data->event_file->tr; 2426 struct hist_field *field = NULL; 2427 u64 constant; 2428 2429 if (kstrtoull(str, 0, &constant)) { 2430 hist_err(tr, HIST_ERR_EXPECT_NUMBER, errpos(str)); 2431 return NULL; 2432 } 2433 2434 *flags |= HIST_FIELD_FL_CONST; 2435 field = create_hist_field(hist_data, NULL, *flags, var_name); 2436 if (!field) 2437 return NULL; 2438 2439 field->constant = constant; 2440 2441 return field; 2442 } 2443 2444 static struct hist_field *parse_atom(struct hist_trigger_data *hist_data, 2445 struct trace_event_file *file, char *str, 2446 unsigned long *flags, char *var_name) 2447 { 2448 char *s, *ref_system = NULL, *ref_event = NULL, *ref_var = str; 2449 struct ftrace_event_field *field = NULL; 2450 struct hist_field *hist_field = NULL; 2451 unsigned long buckets = 0; 2452 int ret = 0; 2453 2454 if (isdigit(str[0])) { 2455 hist_field = parse_const(hist_data, str, var_name, flags); 2456 if (!hist_field) { 2457 ret = -EINVAL; 2458 goto out; 2459 } 2460 return hist_field; 2461 } 2462 2463 s = strchr(str, '.'); 2464 if (s) { 2465 s = strchr(++s, '.'); 2466 if (s) { 2467 ref_system = strsep(&str, "."); 2468 if (!str) { 2469 ret = -EINVAL; 2470 goto out; 2471 } 2472 ref_event = strsep(&str, "."); 2473 if (!str) { 2474 ret = -EINVAL; 2475 goto out; 2476 } 2477 ref_var = str; 2478 } 2479 } 2480 2481 s = local_field_var_ref(hist_data, ref_system, ref_event, ref_var); 2482 if (!s) { 2483 hist_field = parse_var_ref(hist_data, ref_system, 2484 ref_event, ref_var); 2485 if (hist_field) { 2486 if (var_name) { 2487 hist_field = create_alias(hist_data, hist_field, var_name); 2488 if (!hist_field) { 2489 ret = -ENOMEM; 2490 goto out; 2491 } 2492 } 2493 return hist_field; 2494 } 2495 } else 2496 str = s; 2497 2498 field = parse_field(hist_data, file, str, flags, &buckets); 2499 if (IS_ERR(field)) { 2500 ret = PTR_ERR(field); 2501 goto out; 2502 } 2503 2504 hist_field = create_hist_field(hist_data, field, *flags, var_name); 2505 if (!hist_field) { 2506 ret = -ENOMEM; 2507 goto out; 2508 } 2509 hist_field->buckets = buckets; 2510 2511 return hist_field; 2512 out: 2513 return ERR_PTR(ret); 2514 } 2515 2516 static struct hist_field *parse_expr(struct hist_trigger_data *hist_data, 2517 struct trace_event_file *file, 2518 char *str, unsigned long flags, 2519 char *var_name, unsigned int *n_subexprs); 2520 2521 static struct hist_field *parse_unary(struct hist_trigger_data *hist_data, 2522 struct trace_event_file *file, 2523 char *str, unsigned long flags, 2524 char *var_name, unsigned int *n_subexprs) 2525 { 2526 struct hist_field *operand1, *expr = NULL; 2527 unsigned long operand_flags; 2528 int ret = 0; 2529 char *s; 2530 2531 /* Unary minus operator, increment n_subexprs */ 2532 ++*n_subexprs; 2533 2534 /* we support only -(xxx) i.e. explicit parens required */ 2535 2536 if (*n_subexprs > 3) { 2537 hist_err(file->tr, HIST_ERR_TOO_MANY_SUBEXPR, errpos(str)); 2538 ret = -EINVAL; 2539 goto free; 2540 } 2541 2542 str++; /* skip leading '-' */ 2543 2544 s = strchr(str, '('); 2545 if (s) 2546 str++; 2547 else { 2548 ret = -EINVAL; 2549 goto free; 2550 } 2551 2552 s = strrchr(str, ')'); 2553 if (s) { 2554 /* unary minus not supported in sub-expressions */ 2555 if (*(s+1) != '\0') { 2556 hist_err(file->tr, HIST_ERR_UNARY_MINUS_SUBEXPR, 2557 errpos(str)); 2558 ret = -EINVAL; 2559 goto free; 2560 } 2561 *s = '\0'; 2562 } 2563 else { 2564 ret = -EINVAL; /* no closing ')' */ 2565 goto free; 2566 } 2567 2568 flags |= HIST_FIELD_FL_EXPR; 2569 expr = create_hist_field(hist_data, NULL, flags, var_name); 2570 if (!expr) { 2571 ret = -ENOMEM; 2572 goto free; 2573 } 2574 2575 operand_flags = 0; 2576 operand1 = parse_expr(hist_data, file, str, operand_flags, NULL, n_subexprs); 2577 if (IS_ERR(operand1)) { 2578 ret = PTR_ERR(operand1); 2579 goto free; 2580 } 2581 if (operand1->flags & HIST_FIELD_FL_STRING) { 2582 /* String type can not be the operand of unary operator. */ 2583 hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(str)); 2584 destroy_hist_field(operand1, 0); 2585 ret = -EINVAL; 2586 goto free; 2587 } 2588 2589 expr->flags |= operand1->flags & 2590 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS); 2591 expr->fn_num = HIST_FIELD_FN_UMINUS; 2592 expr->operands[0] = operand1; 2593 expr->size = operand1->size; 2594 expr->is_signed = operand1->is_signed; 2595 expr->operator = FIELD_OP_UNARY_MINUS; 2596 expr->name = expr_str(expr, 0); 2597 expr->type = kstrdup_const(operand1->type, GFP_KERNEL); 2598 if (!expr->type) { 2599 ret = -ENOMEM; 2600 goto free; 2601 } 2602 2603 return expr; 2604 free: 2605 destroy_hist_field(expr, 0); 2606 return ERR_PTR(ret); 2607 } 2608 2609 /* 2610 * If the operands are var refs, return pointers the 2611 * variable(s) referenced in var1 and var2, else NULL. 2612 */ 2613 static int check_expr_operands(struct trace_array *tr, 2614 struct hist_field *operand1, 2615 struct hist_field *operand2, 2616 struct hist_field **var1, 2617 struct hist_field **var2) 2618 { 2619 unsigned long operand1_flags = operand1->flags; 2620 unsigned long operand2_flags = operand2->flags; 2621 2622 if ((operand1_flags & HIST_FIELD_FL_VAR_REF) || 2623 (operand1_flags & HIST_FIELD_FL_ALIAS)) { 2624 struct hist_field *var; 2625 2626 var = find_var_field(operand1->var.hist_data, operand1->name); 2627 if (!var) 2628 return -EINVAL; 2629 operand1_flags = var->flags; 2630 *var1 = var; 2631 } 2632 2633 if ((operand2_flags & HIST_FIELD_FL_VAR_REF) || 2634 (operand2_flags & HIST_FIELD_FL_ALIAS)) { 2635 struct hist_field *var; 2636 2637 var = find_var_field(operand2->var.hist_data, operand2->name); 2638 if (!var) 2639 return -EINVAL; 2640 operand2_flags = var->flags; 2641 *var2 = var; 2642 } 2643 2644 if ((operand1_flags & HIST_FIELD_FL_TIMESTAMP_USECS) != 2645 (operand2_flags & HIST_FIELD_FL_TIMESTAMP_USECS)) { 2646 hist_err(tr, HIST_ERR_TIMESTAMP_MISMATCH, 0); 2647 return -EINVAL; 2648 } 2649 2650 return 0; 2651 } 2652 2653 static struct hist_field *parse_expr(struct hist_trigger_data *hist_data, 2654 struct trace_event_file *file, 2655 char *str, unsigned long flags, 2656 char *var_name, unsigned int *n_subexprs) 2657 { 2658 struct hist_field *operand1 = NULL, *operand2 = NULL, *expr = NULL; 2659 struct hist_field *var1 = NULL, *var2 = NULL; 2660 unsigned long operand_flags, operand2_flags; 2661 int field_op, ret = -EINVAL; 2662 char *sep, *operand1_str; 2663 enum hist_field_fn op_fn; 2664 bool combine_consts; 2665 2666 if (*n_subexprs > 3) { 2667 hist_err(file->tr, HIST_ERR_TOO_MANY_SUBEXPR, errpos(str)); 2668 return ERR_PTR(-EINVAL); 2669 } 2670 2671 field_op = contains_operator(str, &sep); 2672 2673 if (field_op == FIELD_OP_NONE) 2674 return parse_atom(hist_data, file, str, &flags, var_name); 2675 2676 if (field_op == FIELD_OP_UNARY_MINUS) 2677 return parse_unary(hist_data, file, str, flags, var_name, n_subexprs); 2678 2679 /* Binary operator found, increment n_subexprs */ 2680 ++*n_subexprs; 2681 2682 /* Split the expression string at the root operator */ 2683 if (!sep) 2684 return ERR_PTR(-EINVAL); 2685 2686 *sep = '\0'; 2687 operand1_str = str; 2688 str = sep+1; 2689 2690 /* Binary operator requires both operands */ 2691 if (*operand1_str == '\0' || *str == '\0') 2692 return ERR_PTR(-EINVAL); 2693 2694 operand_flags = 0; 2695 2696 /* LHS of string is an expression e.g. a+b in a+b+c */ 2697 operand1 = parse_expr(hist_data, file, operand1_str, operand_flags, NULL, n_subexprs); 2698 if (IS_ERR(operand1)) 2699 return ERR_CAST(operand1); 2700 2701 if (operand1->flags & HIST_FIELD_FL_STRING) { 2702 hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(operand1_str)); 2703 ret = -EINVAL; 2704 goto free_op1; 2705 } 2706 2707 /* RHS of string is another expression e.g. c in a+b+c */ 2708 operand_flags = 0; 2709 operand2 = parse_expr(hist_data, file, str, operand_flags, NULL, n_subexprs); 2710 if (IS_ERR(operand2)) { 2711 ret = PTR_ERR(operand2); 2712 goto free_op1; 2713 } 2714 if (operand2->flags & HIST_FIELD_FL_STRING) { 2715 hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(str)); 2716 ret = -EINVAL; 2717 goto free_operands; 2718 } 2719 2720 switch (field_op) { 2721 case FIELD_OP_MINUS: 2722 op_fn = HIST_FIELD_FN_MINUS; 2723 break; 2724 case FIELD_OP_PLUS: 2725 op_fn = HIST_FIELD_FN_PLUS; 2726 break; 2727 case FIELD_OP_DIV: 2728 op_fn = HIST_FIELD_FN_DIV; 2729 break; 2730 case FIELD_OP_MULT: 2731 op_fn = HIST_FIELD_FN_MULT; 2732 break; 2733 default: 2734 ret = -EINVAL; 2735 goto free_operands; 2736 } 2737 2738 ret = check_expr_operands(file->tr, operand1, operand2, &var1, &var2); 2739 if (ret) 2740 goto free_operands; 2741 2742 operand_flags = var1 ? var1->flags : operand1->flags; 2743 operand2_flags = var2 ? var2->flags : operand2->flags; 2744 2745 /* 2746 * If both operands are constant, the expression can be 2747 * collapsed to a single constant. 2748 */ 2749 combine_consts = operand_flags & operand2_flags & HIST_FIELD_FL_CONST; 2750 2751 flags |= combine_consts ? HIST_FIELD_FL_CONST : HIST_FIELD_FL_EXPR; 2752 2753 flags |= operand1->flags & 2754 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS); 2755 2756 expr = create_hist_field(hist_data, NULL, flags, var_name); 2757 if (!expr) { 2758 ret = -ENOMEM; 2759 goto free_operands; 2760 } 2761 2762 operand1->read_once = true; 2763 operand2->read_once = true; 2764 2765 /* The operands are now owned and free'd by 'expr' */ 2766 expr->operands[0] = operand1; 2767 expr->operands[1] = operand2; 2768 2769 if (field_op == FIELD_OP_DIV && 2770 operand2_flags & HIST_FIELD_FL_CONST) { 2771 u64 divisor = var2 ? var2->constant : operand2->constant; 2772 2773 if (!divisor) { 2774 hist_err(file->tr, HIST_ERR_DIVISION_BY_ZERO, errpos(str)); 2775 ret = -EDOM; 2776 goto free_expr; 2777 } 2778 2779 /* 2780 * Copy the divisor here so we don't have to look it up 2781 * later if this is a var ref 2782 */ 2783 operand2->constant = divisor; 2784 op_fn = hist_field_get_div_fn(operand2); 2785 } 2786 2787 expr->fn_num = op_fn; 2788 2789 if (combine_consts) { 2790 if (var1) 2791 expr->operands[0] = var1; 2792 if (var2) 2793 expr->operands[1] = var2; 2794 2795 expr->constant = hist_fn_call(expr, NULL, NULL, NULL, NULL); 2796 expr->fn_num = HIST_FIELD_FN_CONST; 2797 2798 expr->operands[0] = NULL; 2799 expr->operands[1] = NULL; 2800 2801 /* 2802 * var refs won't be destroyed immediately 2803 * See: destroy_hist_field() 2804 */ 2805 destroy_hist_field(operand2, 0); 2806 destroy_hist_field(operand1, 0); 2807 2808 expr->name = expr_str(expr, 0); 2809 } else { 2810 /* The operand sizes should be the same, so just pick one */ 2811 expr->size = operand1->size; 2812 expr->is_signed = operand1->is_signed; 2813 2814 expr->operator = field_op; 2815 expr->type = kstrdup_const(operand1->type, GFP_KERNEL); 2816 if (!expr->type) { 2817 ret = -ENOMEM; 2818 goto free_expr; 2819 } 2820 2821 expr->name = expr_str(expr, 0); 2822 } 2823 2824 return expr; 2825 2826 free_operands: 2827 destroy_hist_field(operand2, 0); 2828 free_op1: 2829 destroy_hist_field(operand1, 0); 2830 return ERR_PTR(ret); 2831 2832 free_expr: 2833 destroy_hist_field(expr, 0); 2834 return ERR_PTR(ret); 2835 } 2836 2837 static char *find_trigger_filter(struct hist_trigger_data *hist_data, 2838 struct trace_event_file *file) 2839 { 2840 struct event_trigger_data *test; 2841 2842 lockdep_assert_held(&event_mutex); 2843 2844 list_for_each_entry(test, &file->triggers, list) { 2845 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 2846 if (test->private_data == hist_data) 2847 return test->filter_str; 2848 } 2849 } 2850 2851 return NULL; 2852 } 2853 2854 static struct event_command trigger_hist_cmd; 2855 static int event_hist_trigger_parse(struct event_command *cmd_ops, 2856 struct trace_event_file *file, 2857 char *glob, char *cmd, 2858 char *param_and_filter); 2859 2860 static bool compatible_keys(struct hist_trigger_data *target_hist_data, 2861 struct hist_trigger_data *hist_data, 2862 unsigned int n_keys) 2863 { 2864 struct hist_field *target_hist_field, *hist_field; 2865 unsigned int n, i, j; 2866 2867 if (hist_data->n_fields - hist_data->n_vals != n_keys) 2868 return false; 2869 2870 i = hist_data->n_vals; 2871 j = target_hist_data->n_vals; 2872 2873 for (n = 0; n < n_keys; n++) { 2874 hist_field = hist_data->fields[i + n]; 2875 target_hist_field = target_hist_data->fields[j + n]; 2876 2877 if (strcmp(hist_field->type, target_hist_field->type) != 0) 2878 return false; 2879 if (hist_field->size != target_hist_field->size) 2880 return false; 2881 if (hist_field->is_signed != target_hist_field->is_signed) 2882 return false; 2883 } 2884 2885 return true; 2886 } 2887 2888 static struct hist_trigger_data * 2889 find_compatible_hist(struct hist_trigger_data *target_hist_data, 2890 struct trace_event_file *file) 2891 { 2892 struct hist_trigger_data *hist_data; 2893 struct event_trigger_data *test; 2894 unsigned int n_keys; 2895 2896 lockdep_assert_held(&event_mutex); 2897 2898 n_keys = target_hist_data->n_fields - target_hist_data->n_vals; 2899 2900 list_for_each_entry(test, &file->triggers, list) { 2901 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 2902 hist_data = test->private_data; 2903 2904 if (compatible_keys(target_hist_data, hist_data, n_keys)) 2905 return hist_data; 2906 } 2907 } 2908 2909 return NULL; 2910 } 2911 2912 static struct trace_event_file *event_file(struct trace_array *tr, 2913 char *system, char *event_name) 2914 { 2915 struct trace_event_file *file; 2916 2917 file = __find_event_file(tr, system, event_name); 2918 if (!file) 2919 return ERR_PTR(-EINVAL); 2920 2921 return file; 2922 } 2923 2924 static struct hist_field * 2925 find_synthetic_field_var(struct hist_trigger_data *target_hist_data, 2926 char *system, char *event_name, char *field_name) 2927 { 2928 struct hist_field *event_var; 2929 char *synthetic_name; 2930 2931 synthetic_name = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL); 2932 if (!synthetic_name) 2933 return ERR_PTR(-ENOMEM); 2934 2935 strcpy(synthetic_name, "synthetic_"); 2936 strcat(synthetic_name, field_name); 2937 2938 event_var = find_event_var(target_hist_data, system, event_name, synthetic_name); 2939 2940 kfree(synthetic_name); 2941 2942 return event_var; 2943 } 2944 2945 /** 2946 * create_field_var_hist - Automatically create a histogram and var for a field 2947 * @target_hist_data: The target hist trigger 2948 * @subsys_name: Optional subsystem name 2949 * @event_name: Optional event name 2950 * @field_name: The name of the field (and the resulting variable) 2951 * 2952 * Hist trigger actions fetch data from variables, not directly from 2953 * events. However, for convenience, users are allowed to directly 2954 * specify an event field in an action, which will be automatically 2955 * converted into a variable on their behalf. 2956 * 2957 * If a user specifies a field on an event that isn't the event the 2958 * histogram currently being defined (the target event histogram), the 2959 * only way that can be accomplished is if a new hist trigger is 2960 * created and the field variable defined on that. 2961 * 2962 * This function creates a new histogram compatible with the target 2963 * event (meaning a histogram with the same key as the target 2964 * histogram), and creates a variable for the specified field, but 2965 * with 'synthetic_' prepended to the variable name in order to avoid 2966 * collision with normal field variables. 2967 * 2968 * Return: The variable created for the field. 2969 */ 2970 static struct hist_field * 2971 create_field_var_hist(struct hist_trigger_data *target_hist_data, 2972 char *subsys_name, char *event_name, char *field_name) 2973 { 2974 struct trace_array *tr = target_hist_data->event_file->tr; 2975 struct hist_trigger_data *hist_data; 2976 unsigned int i, n, first = true; 2977 struct field_var_hist *var_hist; 2978 struct trace_event_file *file; 2979 struct hist_field *key_field; 2980 struct hist_field *event_var; 2981 char *saved_filter; 2982 char *cmd; 2983 int ret; 2984 2985 if (target_hist_data->n_field_var_hists >= SYNTH_FIELDS_MAX) { 2986 hist_err(tr, HIST_ERR_TOO_MANY_FIELD_VARS, errpos(field_name)); 2987 return ERR_PTR(-EINVAL); 2988 } 2989 2990 file = event_file(tr, subsys_name, event_name); 2991 2992 if (IS_ERR(file)) { 2993 hist_err(tr, HIST_ERR_EVENT_FILE_NOT_FOUND, errpos(field_name)); 2994 ret = PTR_ERR(file); 2995 return ERR_PTR(ret); 2996 } 2997 2998 /* 2999 * Look for a histogram compatible with target. We'll use the 3000 * found histogram specification to create a new matching 3001 * histogram with our variable on it. target_hist_data is not 3002 * yet a registered histogram so we can't use that. 3003 */ 3004 hist_data = find_compatible_hist(target_hist_data, file); 3005 if (!hist_data) { 3006 hist_err(tr, HIST_ERR_HIST_NOT_FOUND, errpos(field_name)); 3007 return ERR_PTR(-EINVAL); 3008 } 3009 3010 /* See if a synthetic field variable has already been created */ 3011 event_var = find_synthetic_field_var(target_hist_data, subsys_name, 3012 event_name, field_name); 3013 if (!IS_ERR_OR_NULL(event_var)) 3014 return event_var; 3015 3016 var_hist = kzalloc(sizeof(*var_hist), GFP_KERNEL); 3017 if (!var_hist) 3018 return ERR_PTR(-ENOMEM); 3019 3020 cmd = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL); 3021 if (!cmd) { 3022 kfree(var_hist); 3023 return ERR_PTR(-ENOMEM); 3024 } 3025 3026 /* Use the same keys as the compatible histogram */ 3027 strcat(cmd, "keys="); 3028 3029 for_each_hist_key_field(i, hist_data) { 3030 key_field = hist_data->fields[i]; 3031 if (!first) 3032 strcat(cmd, ","); 3033 strcat(cmd, key_field->field->name); 3034 first = false; 3035 } 3036 3037 /* Create the synthetic field variable specification */ 3038 strcat(cmd, ":synthetic_"); 3039 strcat(cmd, field_name); 3040 strcat(cmd, "="); 3041 strcat(cmd, field_name); 3042 3043 /* Use the same filter as the compatible histogram */ 3044 saved_filter = find_trigger_filter(hist_data, file); 3045 if (saved_filter) { 3046 strcat(cmd, " if "); 3047 strcat(cmd, saved_filter); 3048 } 3049 3050 var_hist->cmd = kstrdup(cmd, GFP_KERNEL); 3051 if (!var_hist->cmd) { 3052 kfree(cmd); 3053 kfree(var_hist); 3054 return ERR_PTR(-ENOMEM); 3055 } 3056 3057 /* Save the compatible histogram information */ 3058 var_hist->hist_data = hist_data; 3059 3060 /* Create the new histogram with our variable */ 3061 ret = event_hist_trigger_parse(&trigger_hist_cmd, file, 3062 "", "hist", cmd); 3063 if (ret) { 3064 kfree(cmd); 3065 kfree(var_hist->cmd); 3066 kfree(var_hist); 3067 hist_err(tr, HIST_ERR_HIST_CREATE_FAIL, errpos(field_name)); 3068 return ERR_PTR(ret); 3069 } 3070 3071 kfree(cmd); 3072 3073 /* If we can't find the variable, something went wrong */ 3074 event_var = find_synthetic_field_var(target_hist_data, subsys_name, 3075 event_name, field_name); 3076 if (IS_ERR_OR_NULL(event_var)) { 3077 kfree(var_hist->cmd); 3078 kfree(var_hist); 3079 hist_err(tr, HIST_ERR_SYNTH_VAR_NOT_FOUND, errpos(field_name)); 3080 return ERR_PTR(-EINVAL); 3081 } 3082 3083 n = target_hist_data->n_field_var_hists; 3084 target_hist_data->field_var_hists[n] = var_hist; 3085 target_hist_data->n_field_var_hists++; 3086 3087 return event_var; 3088 } 3089 3090 static struct hist_field * 3091 find_target_event_var(struct hist_trigger_data *hist_data, 3092 char *subsys_name, char *event_name, char *var_name) 3093 { 3094 struct trace_event_file *file = hist_data->event_file; 3095 struct hist_field *hist_field = NULL; 3096 3097 if (subsys_name) { 3098 struct trace_event_call *call; 3099 3100 if (!event_name) 3101 return NULL; 3102 3103 call = file->event_call; 3104 3105 if (strcmp(subsys_name, call->class->system) != 0) 3106 return NULL; 3107 3108 if (strcmp(event_name, trace_event_name(call)) != 0) 3109 return NULL; 3110 } 3111 3112 hist_field = find_var_field(hist_data, var_name); 3113 3114 return hist_field; 3115 } 3116 3117 static inline void __update_field_vars(struct tracing_map_elt *elt, 3118 struct trace_buffer *buffer, 3119 struct ring_buffer_event *rbe, 3120 void *rec, 3121 struct field_var **field_vars, 3122 unsigned int n_field_vars, 3123 unsigned int field_var_str_start) 3124 { 3125 struct hist_elt_data *elt_data = elt->private_data; 3126 unsigned int i, j, var_idx; 3127 u64 var_val; 3128 3129 /* Make sure stacktrace can fit in the string variable length */ 3130 BUILD_BUG_ON((HIST_STACKTRACE_DEPTH + 1) * sizeof(long) >= STR_VAR_LEN_MAX); 3131 3132 for (i = 0, j = field_var_str_start; i < n_field_vars; i++) { 3133 struct field_var *field_var = field_vars[i]; 3134 struct hist_field *var = field_var->var; 3135 struct hist_field *val = field_var->val; 3136 3137 var_val = hist_fn_call(val, elt, buffer, rbe, rec); 3138 var_idx = var->var.idx; 3139 3140 if (val->flags & (HIST_FIELD_FL_STRING | 3141 HIST_FIELD_FL_STACKTRACE)) { 3142 char *str = elt_data->field_var_str[j++]; 3143 char *val_str = (char *)(uintptr_t)var_val; 3144 unsigned int size; 3145 3146 if (val->flags & HIST_FIELD_FL_STRING) { 3147 size = min(val->size, STR_VAR_LEN_MAX); 3148 strscpy(str, val_str, size); 3149 } else { 3150 char *stack_start = str + sizeof(unsigned long); 3151 int e; 3152 3153 e = stack_trace_save((void *)stack_start, 3154 HIST_STACKTRACE_DEPTH, 3155 HIST_STACKTRACE_SKIP); 3156 if (e < HIST_STACKTRACE_DEPTH - 1) 3157 ((unsigned long *)stack_start)[e] = 0; 3158 *((unsigned long *)str) = e; 3159 } 3160 var_val = (u64)(uintptr_t)str; 3161 } 3162 tracing_map_set_var(elt, var_idx, var_val); 3163 } 3164 } 3165 3166 static void update_field_vars(struct hist_trigger_data *hist_data, 3167 struct tracing_map_elt *elt, 3168 struct trace_buffer *buffer, 3169 struct ring_buffer_event *rbe, 3170 void *rec) 3171 { 3172 __update_field_vars(elt, buffer, rbe, rec, hist_data->field_vars, 3173 hist_data->n_field_vars, 0); 3174 } 3175 3176 static void save_track_data_vars(struct hist_trigger_data *hist_data, 3177 struct tracing_map_elt *elt, 3178 struct trace_buffer *buffer, void *rec, 3179 struct ring_buffer_event *rbe, void *key, 3180 struct action_data *data, u64 *var_ref_vals) 3181 { 3182 __update_field_vars(elt, buffer, rbe, rec, hist_data->save_vars, 3183 hist_data->n_save_vars, hist_data->n_field_var_str); 3184 } 3185 3186 static struct hist_field *create_var(struct hist_trigger_data *hist_data, 3187 struct trace_event_file *file, 3188 char *name, int size, const char *type) 3189 { 3190 struct hist_field *var; 3191 int idx; 3192 3193 if (find_var(hist_data, file, name) && !hist_data->remove) { 3194 var = ERR_PTR(-EINVAL); 3195 goto out; 3196 } 3197 3198 var = kzalloc(sizeof(struct hist_field), GFP_KERNEL); 3199 if (!var) { 3200 var = ERR_PTR(-ENOMEM); 3201 goto out; 3202 } 3203 3204 idx = tracing_map_add_var(hist_data->map); 3205 if (idx < 0) { 3206 kfree(var); 3207 var = ERR_PTR(-EINVAL); 3208 goto out; 3209 } 3210 3211 var->ref = 1; 3212 var->flags = HIST_FIELD_FL_VAR; 3213 var->var.idx = idx; 3214 var->var.hist_data = var->hist_data = hist_data; 3215 var->size = size; 3216 var->var.name = kstrdup(name, GFP_KERNEL); 3217 var->type = kstrdup_const(type, GFP_KERNEL); 3218 if (!var->var.name || !var->type) { 3219 kfree_const(var->type); 3220 kfree(var->var.name); 3221 kfree(var); 3222 var = ERR_PTR(-ENOMEM); 3223 } 3224 out: 3225 return var; 3226 } 3227 3228 static struct field_var *create_field_var(struct hist_trigger_data *hist_data, 3229 struct trace_event_file *file, 3230 char *field_name) 3231 { 3232 struct hist_field *val = NULL, *var = NULL; 3233 unsigned long flags = HIST_FIELD_FL_VAR; 3234 struct trace_array *tr = file->tr; 3235 struct field_var *field_var; 3236 int ret = 0; 3237 3238 if (hist_data->n_field_vars >= SYNTH_FIELDS_MAX) { 3239 hist_err(tr, HIST_ERR_TOO_MANY_FIELD_VARS, errpos(field_name)); 3240 ret = -EINVAL; 3241 goto err; 3242 } 3243 3244 val = parse_atom(hist_data, file, field_name, &flags, NULL); 3245 if (IS_ERR(val)) { 3246 hist_err(tr, HIST_ERR_FIELD_VAR_PARSE_FAIL, errpos(field_name)); 3247 ret = PTR_ERR(val); 3248 goto err; 3249 } 3250 3251 var = create_var(hist_data, file, field_name, val->size, val->type); 3252 if (IS_ERR(var)) { 3253 hist_err(tr, HIST_ERR_VAR_CREATE_FIND_FAIL, errpos(field_name)); 3254 kfree(val); 3255 ret = PTR_ERR(var); 3256 goto err; 3257 } 3258 3259 field_var = kzalloc(sizeof(struct field_var), GFP_KERNEL); 3260 if (!field_var) { 3261 kfree(val); 3262 kfree(var); 3263 ret = -ENOMEM; 3264 goto err; 3265 } 3266 3267 field_var->var = var; 3268 field_var->val = val; 3269 out: 3270 return field_var; 3271 err: 3272 field_var = ERR_PTR(ret); 3273 goto out; 3274 } 3275 3276 /** 3277 * create_target_field_var - Automatically create a variable for a field 3278 * @target_hist_data: The target hist trigger 3279 * @subsys_name: Optional subsystem name 3280 * @event_name: Optional event name 3281 * @var_name: The name of the field (and the resulting variable) 3282 * 3283 * Hist trigger actions fetch data from variables, not directly from 3284 * events. However, for convenience, users are allowed to directly 3285 * specify an event field in an action, which will be automatically 3286 * converted into a variable on their behalf. 3287 * 3288 * This function creates a field variable with the name var_name on 3289 * the hist trigger currently being defined on the target event. If 3290 * subsys_name and event_name are specified, this function simply 3291 * verifies that they do in fact match the target event subsystem and 3292 * event name. 3293 * 3294 * Return: The variable created for the field. 3295 */ 3296 static struct field_var * 3297 create_target_field_var(struct hist_trigger_data *target_hist_data, 3298 char *subsys_name, char *event_name, char *var_name) 3299 { 3300 struct trace_event_file *file = target_hist_data->event_file; 3301 3302 if (subsys_name) { 3303 struct trace_event_call *call; 3304 3305 if (!event_name) 3306 return NULL; 3307 3308 call = file->event_call; 3309 3310 if (strcmp(subsys_name, call->class->system) != 0) 3311 return NULL; 3312 3313 if (strcmp(event_name, trace_event_name(call)) != 0) 3314 return NULL; 3315 } 3316 3317 return create_field_var(target_hist_data, file, var_name); 3318 } 3319 3320 static bool check_track_val_max(u64 track_val, u64 var_val) 3321 { 3322 if (var_val <= track_val) 3323 return false; 3324 3325 return true; 3326 } 3327 3328 static bool check_track_val_changed(u64 track_val, u64 var_val) 3329 { 3330 if (var_val == track_val) 3331 return false; 3332 3333 return true; 3334 } 3335 3336 static u64 get_track_val(struct hist_trigger_data *hist_data, 3337 struct tracing_map_elt *elt, 3338 struct action_data *data) 3339 { 3340 unsigned int track_var_idx = data->track_data.track_var->var.idx; 3341 u64 track_val; 3342 3343 track_val = tracing_map_read_var(elt, track_var_idx); 3344 3345 return track_val; 3346 } 3347 3348 static void save_track_val(struct hist_trigger_data *hist_data, 3349 struct tracing_map_elt *elt, 3350 struct action_data *data, u64 var_val) 3351 { 3352 unsigned int track_var_idx = data->track_data.track_var->var.idx; 3353 3354 tracing_map_set_var(elt, track_var_idx, var_val); 3355 } 3356 3357 static void save_track_data(struct hist_trigger_data *hist_data, 3358 struct tracing_map_elt *elt, 3359 struct trace_buffer *buffer, void *rec, 3360 struct ring_buffer_event *rbe, void *key, 3361 struct action_data *data, u64 *var_ref_vals) 3362 { 3363 if (data->track_data.save_data) 3364 data->track_data.save_data(hist_data, elt, buffer, rec, rbe, 3365 key, data, var_ref_vals); 3366 } 3367 3368 static bool check_track_val(struct tracing_map_elt *elt, 3369 struct action_data *data, 3370 u64 var_val) 3371 { 3372 struct hist_trigger_data *hist_data; 3373 u64 track_val; 3374 3375 hist_data = data->track_data.track_var->hist_data; 3376 track_val = get_track_val(hist_data, elt, data); 3377 3378 return data->track_data.check_val(track_val, var_val); 3379 } 3380 3381 #ifdef CONFIG_TRACER_SNAPSHOT 3382 static bool cond_snapshot_update(struct trace_array *tr, void *cond_data) 3383 { 3384 /* called with tr->max_lock held */ 3385 struct track_data *track_data = tr->cond_snapshot->cond_data; 3386 struct hist_elt_data *elt_data, *track_elt_data; 3387 struct snapshot_context *context = cond_data; 3388 struct action_data *action; 3389 u64 track_val; 3390 3391 if (!track_data) 3392 return false; 3393 3394 action = track_data->action_data; 3395 3396 track_val = get_track_val(track_data->hist_data, context->elt, 3397 track_data->action_data); 3398 3399 if (!action->track_data.check_val(track_data->track_val, track_val)) 3400 return false; 3401 3402 track_data->track_val = track_val; 3403 memcpy(track_data->key, context->key, track_data->key_len); 3404 3405 elt_data = context->elt->private_data; 3406 track_elt_data = track_data->elt.private_data; 3407 if (elt_data->comm) 3408 strncpy(track_elt_data->comm, elt_data->comm, TASK_COMM_LEN); 3409 3410 track_data->updated = true; 3411 3412 return true; 3413 } 3414 3415 static void save_track_data_snapshot(struct hist_trigger_data *hist_data, 3416 struct tracing_map_elt *elt, 3417 struct trace_buffer *buffer, void *rec, 3418 struct ring_buffer_event *rbe, void *key, 3419 struct action_data *data, 3420 u64 *var_ref_vals) 3421 { 3422 struct trace_event_file *file = hist_data->event_file; 3423 struct snapshot_context context; 3424 3425 context.elt = elt; 3426 context.key = key; 3427 3428 tracing_snapshot_cond(file->tr, &context); 3429 } 3430 3431 static void hist_trigger_print_key(struct seq_file *m, 3432 struct hist_trigger_data *hist_data, 3433 void *key, 3434 struct tracing_map_elt *elt); 3435 3436 static struct action_data *snapshot_action(struct hist_trigger_data *hist_data) 3437 { 3438 unsigned int i; 3439 3440 if (!hist_data->n_actions) 3441 return NULL; 3442 3443 for (i = 0; i < hist_data->n_actions; i++) { 3444 struct action_data *data = hist_data->actions[i]; 3445 3446 if (data->action == ACTION_SNAPSHOT) 3447 return data; 3448 } 3449 3450 return NULL; 3451 } 3452 3453 static void track_data_snapshot_print(struct seq_file *m, 3454 struct hist_trigger_data *hist_data) 3455 { 3456 struct trace_event_file *file = hist_data->event_file; 3457 struct track_data *track_data; 3458 struct action_data *action; 3459 3460 track_data = tracing_cond_snapshot_data(file->tr); 3461 if (!track_data) 3462 return; 3463 3464 if (!track_data->updated) 3465 return; 3466 3467 action = snapshot_action(hist_data); 3468 if (!action) 3469 return; 3470 3471 seq_puts(m, "\nSnapshot taken (see tracing/snapshot). Details:\n"); 3472 seq_printf(m, "\ttriggering value { %s(%s) }: %10llu", 3473 action->handler == HANDLER_ONMAX ? "onmax" : "onchange", 3474 action->track_data.var_str, track_data->track_val); 3475 3476 seq_puts(m, "\ttriggered by event with key: "); 3477 hist_trigger_print_key(m, hist_data, track_data->key, &track_data->elt); 3478 seq_putc(m, '\n'); 3479 } 3480 #else 3481 static bool cond_snapshot_update(struct trace_array *tr, void *cond_data) 3482 { 3483 return false; 3484 } 3485 static void save_track_data_snapshot(struct hist_trigger_data *hist_data, 3486 struct tracing_map_elt *elt, 3487 struct trace_buffer *buffer, void *rec, 3488 struct ring_buffer_event *rbe, void *key, 3489 struct action_data *data, 3490 u64 *var_ref_vals) {} 3491 static void track_data_snapshot_print(struct seq_file *m, 3492 struct hist_trigger_data *hist_data) {} 3493 #endif /* CONFIG_TRACER_SNAPSHOT */ 3494 3495 static void track_data_print(struct seq_file *m, 3496 struct hist_trigger_data *hist_data, 3497 struct tracing_map_elt *elt, 3498 struct action_data *data) 3499 { 3500 u64 track_val = get_track_val(hist_data, elt, data); 3501 unsigned int i, save_var_idx; 3502 3503 if (data->handler == HANDLER_ONMAX) 3504 seq_printf(m, "\n\tmax: %10llu", track_val); 3505 else if (data->handler == HANDLER_ONCHANGE) 3506 seq_printf(m, "\n\tchanged: %10llu", track_val); 3507 3508 if (data->action == ACTION_SNAPSHOT) 3509 return; 3510 3511 for (i = 0; i < hist_data->n_save_vars; i++) { 3512 struct hist_field *save_val = hist_data->save_vars[i]->val; 3513 struct hist_field *save_var = hist_data->save_vars[i]->var; 3514 u64 val; 3515 3516 save_var_idx = save_var->var.idx; 3517 3518 val = tracing_map_read_var(elt, save_var_idx); 3519 3520 if (save_val->flags & HIST_FIELD_FL_STRING) { 3521 seq_printf(m, " %s: %-32s", save_var->var.name, 3522 (char *)(uintptr_t)(val)); 3523 } else 3524 seq_printf(m, " %s: %10llu", save_var->var.name, val); 3525 } 3526 } 3527 3528 static void ontrack_action(struct hist_trigger_data *hist_data, 3529 struct tracing_map_elt *elt, 3530 struct trace_buffer *buffer, void *rec, 3531 struct ring_buffer_event *rbe, void *key, 3532 struct action_data *data, u64 *var_ref_vals) 3533 { 3534 u64 var_val = var_ref_vals[data->track_data.var_ref->var_ref_idx]; 3535 3536 if (check_track_val(elt, data, var_val)) { 3537 save_track_val(hist_data, elt, data, var_val); 3538 save_track_data(hist_data, elt, buffer, rec, rbe, 3539 key, data, var_ref_vals); 3540 } 3541 } 3542 3543 static void action_data_destroy(struct action_data *data) 3544 { 3545 unsigned int i; 3546 3547 lockdep_assert_held(&event_mutex); 3548 3549 kfree(data->action_name); 3550 3551 for (i = 0; i < data->n_params; i++) 3552 kfree(data->params[i]); 3553 3554 if (data->synth_event) 3555 data->synth_event->ref--; 3556 3557 kfree(data->synth_event_name); 3558 3559 kfree(data); 3560 } 3561 3562 static void track_data_destroy(struct hist_trigger_data *hist_data, 3563 struct action_data *data) 3564 { 3565 struct trace_event_file *file = hist_data->event_file; 3566 3567 destroy_hist_field(data->track_data.track_var, 0); 3568 3569 if (data->action == ACTION_SNAPSHOT) { 3570 struct track_data *track_data; 3571 3572 track_data = tracing_cond_snapshot_data(file->tr); 3573 if (track_data && track_data->hist_data == hist_data) { 3574 tracing_snapshot_cond_disable(file->tr); 3575 track_data_free(track_data); 3576 } 3577 } 3578 3579 kfree(data->track_data.var_str); 3580 3581 action_data_destroy(data); 3582 } 3583 3584 static int action_create(struct hist_trigger_data *hist_data, 3585 struct action_data *data); 3586 3587 static int track_data_create(struct hist_trigger_data *hist_data, 3588 struct action_data *data) 3589 { 3590 struct hist_field *var_field, *ref_field, *track_var = NULL; 3591 struct trace_event_file *file = hist_data->event_file; 3592 struct trace_array *tr = file->tr; 3593 char *track_data_var_str; 3594 int ret = 0; 3595 3596 track_data_var_str = data->track_data.var_str; 3597 if (track_data_var_str[0] != '$') { 3598 hist_err(tr, HIST_ERR_ONX_NOT_VAR, errpos(track_data_var_str)); 3599 return -EINVAL; 3600 } 3601 track_data_var_str++; 3602 3603 var_field = find_target_event_var(hist_data, NULL, NULL, track_data_var_str); 3604 if (!var_field) { 3605 hist_err(tr, HIST_ERR_ONX_VAR_NOT_FOUND, errpos(track_data_var_str)); 3606 return -EINVAL; 3607 } 3608 3609 ref_field = create_var_ref(hist_data, var_field, NULL, NULL); 3610 if (!ref_field) 3611 return -ENOMEM; 3612 3613 data->track_data.var_ref = ref_field; 3614 3615 if (data->handler == HANDLER_ONMAX) 3616 track_var = create_var(hist_data, file, "__max", sizeof(u64), "u64"); 3617 if (IS_ERR(track_var)) { 3618 hist_err(tr, HIST_ERR_ONX_VAR_CREATE_FAIL, 0); 3619 ret = PTR_ERR(track_var); 3620 goto out; 3621 } 3622 3623 if (data->handler == HANDLER_ONCHANGE) 3624 track_var = create_var(hist_data, file, "__change", sizeof(u64), "u64"); 3625 if (IS_ERR(track_var)) { 3626 hist_err(tr, HIST_ERR_ONX_VAR_CREATE_FAIL, 0); 3627 ret = PTR_ERR(track_var); 3628 goto out; 3629 } 3630 data->track_data.track_var = track_var; 3631 3632 ret = action_create(hist_data, data); 3633 out: 3634 return ret; 3635 } 3636 3637 static int parse_action_params(struct trace_array *tr, char *params, 3638 struct action_data *data) 3639 { 3640 char *param, *saved_param; 3641 bool first_param = true; 3642 int ret = 0; 3643 3644 while (params) { 3645 if (data->n_params >= SYNTH_FIELDS_MAX) { 3646 hist_err(tr, HIST_ERR_TOO_MANY_PARAMS, 0); 3647 ret = -EINVAL; 3648 goto out; 3649 } 3650 3651 param = strsep(¶ms, ","); 3652 if (!param) { 3653 hist_err(tr, HIST_ERR_PARAM_NOT_FOUND, 0); 3654 ret = -EINVAL; 3655 goto out; 3656 } 3657 3658 param = strstrip(param); 3659 if (strlen(param) < 2) { 3660 hist_err(tr, HIST_ERR_INVALID_PARAM, errpos(param)); 3661 ret = -EINVAL; 3662 goto out; 3663 } 3664 3665 saved_param = kstrdup(param, GFP_KERNEL); 3666 if (!saved_param) { 3667 ret = -ENOMEM; 3668 goto out; 3669 } 3670 3671 if (first_param && data->use_trace_keyword) { 3672 data->synth_event_name = saved_param; 3673 first_param = false; 3674 continue; 3675 } 3676 first_param = false; 3677 3678 data->params[data->n_params++] = saved_param; 3679 } 3680 out: 3681 return ret; 3682 } 3683 3684 static int action_parse(struct trace_array *tr, char *str, struct action_data *data, 3685 enum handler_id handler) 3686 { 3687 char *action_name; 3688 int ret = 0; 3689 3690 strsep(&str, "."); 3691 if (!str) { 3692 hist_err(tr, HIST_ERR_ACTION_NOT_FOUND, 0); 3693 ret = -EINVAL; 3694 goto out; 3695 } 3696 3697 action_name = strsep(&str, "("); 3698 if (!action_name || !str) { 3699 hist_err(tr, HIST_ERR_ACTION_NOT_FOUND, 0); 3700 ret = -EINVAL; 3701 goto out; 3702 } 3703 3704 if (str_has_prefix(action_name, "save")) { 3705 char *params = strsep(&str, ")"); 3706 3707 if (!params) { 3708 hist_err(tr, HIST_ERR_NO_SAVE_PARAMS, 0); 3709 ret = -EINVAL; 3710 goto out; 3711 } 3712 3713 ret = parse_action_params(tr, params, data); 3714 if (ret) 3715 goto out; 3716 3717 if (handler == HANDLER_ONMAX) 3718 data->track_data.check_val = check_track_val_max; 3719 else if (handler == HANDLER_ONCHANGE) 3720 data->track_data.check_val = check_track_val_changed; 3721 else { 3722 hist_err(tr, HIST_ERR_ACTION_MISMATCH, errpos(action_name)); 3723 ret = -EINVAL; 3724 goto out; 3725 } 3726 3727 data->track_data.save_data = save_track_data_vars; 3728 data->fn = ontrack_action; 3729 data->action = ACTION_SAVE; 3730 } else if (str_has_prefix(action_name, "snapshot")) { 3731 char *params = strsep(&str, ")"); 3732 3733 if (!str) { 3734 hist_err(tr, HIST_ERR_NO_CLOSING_PAREN, errpos(params)); 3735 ret = -EINVAL; 3736 goto out; 3737 } 3738 3739 if (handler == HANDLER_ONMAX) 3740 data->track_data.check_val = check_track_val_max; 3741 else if (handler == HANDLER_ONCHANGE) 3742 data->track_data.check_val = check_track_val_changed; 3743 else { 3744 hist_err(tr, HIST_ERR_ACTION_MISMATCH, errpos(action_name)); 3745 ret = -EINVAL; 3746 goto out; 3747 } 3748 3749 data->track_data.save_data = save_track_data_snapshot; 3750 data->fn = ontrack_action; 3751 data->action = ACTION_SNAPSHOT; 3752 } else { 3753 char *params = strsep(&str, ")"); 3754 3755 if (str_has_prefix(action_name, "trace")) 3756 data->use_trace_keyword = true; 3757 3758 if (params) { 3759 ret = parse_action_params(tr, params, data); 3760 if (ret) 3761 goto out; 3762 } 3763 3764 if (handler == HANDLER_ONMAX) 3765 data->track_data.check_val = check_track_val_max; 3766 else if (handler == HANDLER_ONCHANGE) 3767 data->track_data.check_val = check_track_val_changed; 3768 3769 if (handler != HANDLER_ONMATCH) { 3770 data->track_data.save_data = action_trace; 3771 data->fn = ontrack_action; 3772 } else 3773 data->fn = action_trace; 3774 3775 data->action = ACTION_TRACE; 3776 } 3777 3778 data->action_name = kstrdup(action_name, GFP_KERNEL); 3779 if (!data->action_name) { 3780 ret = -ENOMEM; 3781 goto out; 3782 } 3783 3784 data->handler = handler; 3785 out: 3786 return ret; 3787 } 3788 3789 static struct action_data *track_data_parse(struct hist_trigger_data *hist_data, 3790 char *str, enum handler_id handler) 3791 { 3792 struct action_data *data; 3793 int ret = -EINVAL; 3794 char *var_str; 3795 3796 data = kzalloc(sizeof(*data), GFP_KERNEL); 3797 if (!data) 3798 return ERR_PTR(-ENOMEM); 3799 3800 var_str = strsep(&str, ")"); 3801 if (!var_str || !str) { 3802 ret = -EINVAL; 3803 goto free; 3804 } 3805 3806 data->track_data.var_str = kstrdup(var_str, GFP_KERNEL); 3807 if (!data->track_data.var_str) { 3808 ret = -ENOMEM; 3809 goto free; 3810 } 3811 3812 ret = action_parse(hist_data->event_file->tr, str, data, handler); 3813 if (ret) 3814 goto free; 3815 out: 3816 return data; 3817 free: 3818 track_data_destroy(hist_data, data); 3819 data = ERR_PTR(ret); 3820 goto out; 3821 } 3822 3823 static void onmatch_destroy(struct action_data *data) 3824 { 3825 kfree(data->match_data.event); 3826 kfree(data->match_data.event_system); 3827 3828 action_data_destroy(data); 3829 } 3830 3831 static void destroy_field_var(struct field_var *field_var) 3832 { 3833 if (!field_var) 3834 return; 3835 3836 destroy_hist_field(field_var->var, 0); 3837 destroy_hist_field(field_var->val, 0); 3838 3839 kfree(field_var); 3840 } 3841 3842 static void destroy_field_vars(struct hist_trigger_data *hist_data) 3843 { 3844 unsigned int i; 3845 3846 for (i = 0; i < hist_data->n_field_vars; i++) 3847 destroy_field_var(hist_data->field_vars[i]); 3848 3849 for (i = 0; i < hist_data->n_save_vars; i++) 3850 destroy_field_var(hist_data->save_vars[i]); 3851 } 3852 3853 static void save_field_var(struct hist_trigger_data *hist_data, 3854 struct field_var *field_var) 3855 { 3856 hist_data->field_vars[hist_data->n_field_vars++] = field_var; 3857 3858 /* Stack traces are saved in the string storage too */ 3859 if (field_var->val->flags & (HIST_FIELD_FL_STRING | HIST_FIELD_FL_STACKTRACE)) 3860 hist_data->n_field_var_str++; 3861 } 3862 3863 3864 static int check_synth_field(struct synth_event *event, 3865 struct hist_field *hist_field, 3866 unsigned int field_pos) 3867 { 3868 struct synth_field *field; 3869 3870 if (field_pos >= event->n_fields) 3871 return -EINVAL; 3872 3873 field = event->fields[field_pos]; 3874 3875 /* 3876 * A dynamic string synth field can accept static or 3877 * dynamic. A static string synth field can only accept a 3878 * same-sized static string, which is checked for later. 3879 */ 3880 if (strstr(hist_field->type, "char[") && field->is_string 3881 && field->is_dynamic) 3882 return 0; 3883 3884 if (strstr(hist_field->type, "long[") && field->is_stack) 3885 return 0; 3886 3887 if (strcmp(field->type, hist_field->type) != 0) { 3888 if (field->size != hist_field->size || 3889 (!field->is_string && field->is_signed != hist_field->is_signed)) 3890 return -EINVAL; 3891 } 3892 3893 return 0; 3894 } 3895 3896 static struct hist_field * 3897 trace_action_find_var(struct hist_trigger_data *hist_data, 3898 struct action_data *data, 3899 char *system, char *event, char *var) 3900 { 3901 struct trace_array *tr = hist_data->event_file->tr; 3902 struct hist_field *hist_field; 3903 3904 var++; /* skip '$' */ 3905 3906 hist_field = find_target_event_var(hist_data, system, event, var); 3907 if (!hist_field) { 3908 if (!system && data->handler == HANDLER_ONMATCH) { 3909 system = data->match_data.event_system; 3910 event = data->match_data.event; 3911 } 3912 3913 hist_field = find_event_var(hist_data, system, event, var); 3914 } 3915 3916 if (!hist_field) 3917 hist_err(tr, HIST_ERR_PARAM_NOT_FOUND, errpos(var)); 3918 3919 return hist_field; 3920 } 3921 3922 static struct hist_field * 3923 trace_action_create_field_var(struct hist_trigger_data *hist_data, 3924 struct action_data *data, char *system, 3925 char *event, char *var) 3926 { 3927 struct hist_field *hist_field = NULL; 3928 struct field_var *field_var; 3929 3930 /* 3931 * First try to create a field var on the target event (the 3932 * currently being defined). This will create a variable for 3933 * unqualified fields on the target event, or if qualified, 3934 * target fields that have qualified names matching the target. 3935 */ 3936 field_var = create_target_field_var(hist_data, system, event, var); 3937 3938 if (field_var && !IS_ERR(field_var)) { 3939 save_field_var(hist_data, field_var); 3940 hist_field = field_var->var; 3941 } else { 3942 field_var = NULL; 3943 /* 3944 * If no explicit system.event is specified, default to 3945 * looking for fields on the onmatch(system.event.xxx) 3946 * event. 3947 */ 3948 if (!system && data->handler == HANDLER_ONMATCH) { 3949 system = data->match_data.event_system; 3950 event = data->match_data.event; 3951 } 3952 3953 if (!event) 3954 goto free; 3955 /* 3956 * At this point, we're looking at a field on another 3957 * event. Because we can't modify a hist trigger on 3958 * another event to add a variable for a field, we need 3959 * to create a new trigger on that event and create the 3960 * variable at the same time. 3961 */ 3962 hist_field = create_field_var_hist(hist_data, system, event, var); 3963 if (IS_ERR(hist_field)) 3964 goto free; 3965 } 3966 out: 3967 return hist_field; 3968 free: 3969 destroy_field_var(field_var); 3970 hist_field = NULL; 3971 goto out; 3972 } 3973 3974 static int trace_action_create(struct hist_trigger_data *hist_data, 3975 struct action_data *data) 3976 { 3977 struct trace_array *tr = hist_data->event_file->tr; 3978 char *event_name, *param, *system = NULL; 3979 struct hist_field *hist_field, *var_ref; 3980 unsigned int i; 3981 unsigned int field_pos = 0; 3982 struct synth_event *event; 3983 char *synth_event_name; 3984 int var_ref_idx, ret = 0; 3985 3986 lockdep_assert_held(&event_mutex); 3987 3988 /* Sanity check to avoid out-of-bound write on 'data->var_ref_idx' */ 3989 if (data->n_params > SYNTH_FIELDS_MAX) 3990 return -EINVAL; 3991 3992 if (data->use_trace_keyword) 3993 synth_event_name = data->synth_event_name; 3994 else 3995 synth_event_name = data->action_name; 3996 3997 event = find_synth_event(synth_event_name); 3998 if (!event) { 3999 hist_err(tr, HIST_ERR_SYNTH_EVENT_NOT_FOUND, errpos(synth_event_name)); 4000 return -EINVAL; 4001 } 4002 4003 event->ref++; 4004 4005 for (i = 0; i < data->n_params; i++) { 4006 char *p; 4007 4008 p = param = kstrdup(data->params[i], GFP_KERNEL); 4009 if (!param) { 4010 ret = -ENOMEM; 4011 goto err; 4012 } 4013 4014 system = strsep(¶m, "."); 4015 if (!param) { 4016 param = (char *)system; 4017 system = event_name = NULL; 4018 } else { 4019 event_name = strsep(¶m, "."); 4020 if (!param) { 4021 kfree(p); 4022 ret = -EINVAL; 4023 goto err; 4024 } 4025 } 4026 4027 if (param[0] == '$') 4028 hist_field = trace_action_find_var(hist_data, data, 4029 system, event_name, 4030 param); 4031 else 4032 hist_field = trace_action_create_field_var(hist_data, 4033 data, 4034 system, 4035 event_name, 4036 param); 4037 4038 if (!hist_field) { 4039 kfree(p); 4040 ret = -EINVAL; 4041 goto err; 4042 } 4043 4044 if (check_synth_field(event, hist_field, field_pos) == 0) { 4045 var_ref = create_var_ref(hist_data, hist_field, 4046 system, event_name); 4047 if (!var_ref) { 4048 kfree(p); 4049 ret = -ENOMEM; 4050 goto err; 4051 } 4052 4053 var_ref_idx = find_var_ref_idx(hist_data, var_ref); 4054 if (WARN_ON(var_ref_idx < 0)) { 4055 kfree(p); 4056 ret = var_ref_idx; 4057 goto err; 4058 } 4059 4060 data->var_ref_idx[i] = var_ref_idx; 4061 4062 field_pos++; 4063 kfree(p); 4064 continue; 4065 } 4066 4067 hist_err(tr, HIST_ERR_SYNTH_TYPE_MISMATCH, errpos(param)); 4068 kfree(p); 4069 ret = -EINVAL; 4070 goto err; 4071 } 4072 4073 if (field_pos != event->n_fields) { 4074 hist_err(tr, HIST_ERR_SYNTH_COUNT_MISMATCH, errpos(event->name)); 4075 ret = -EINVAL; 4076 goto err; 4077 } 4078 4079 data->synth_event = event; 4080 out: 4081 return ret; 4082 err: 4083 event->ref--; 4084 4085 goto out; 4086 } 4087 4088 static int action_create(struct hist_trigger_data *hist_data, 4089 struct action_data *data) 4090 { 4091 struct trace_event_file *file = hist_data->event_file; 4092 struct trace_array *tr = file->tr; 4093 struct track_data *track_data; 4094 struct field_var *field_var; 4095 unsigned int i; 4096 char *param; 4097 int ret = 0; 4098 4099 if (data->action == ACTION_TRACE) 4100 return trace_action_create(hist_data, data); 4101 4102 if (data->action == ACTION_SNAPSHOT) { 4103 track_data = track_data_alloc(hist_data->key_size, data, hist_data); 4104 if (IS_ERR(track_data)) { 4105 ret = PTR_ERR(track_data); 4106 goto out; 4107 } 4108 4109 ret = tracing_snapshot_cond_enable(file->tr, track_data, 4110 cond_snapshot_update); 4111 if (ret) 4112 track_data_free(track_data); 4113 4114 goto out; 4115 } 4116 4117 if (data->action == ACTION_SAVE) { 4118 if (hist_data->n_save_vars) { 4119 ret = -EEXIST; 4120 hist_err(tr, HIST_ERR_TOO_MANY_SAVE_ACTIONS, 0); 4121 goto out; 4122 } 4123 4124 for (i = 0; i < data->n_params; i++) { 4125 param = kstrdup(data->params[i], GFP_KERNEL); 4126 if (!param) { 4127 ret = -ENOMEM; 4128 goto out; 4129 } 4130 4131 field_var = create_target_field_var(hist_data, NULL, NULL, param); 4132 if (IS_ERR(field_var)) { 4133 hist_err(tr, HIST_ERR_FIELD_VAR_CREATE_FAIL, 4134 errpos(param)); 4135 ret = PTR_ERR(field_var); 4136 kfree(param); 4137 goto out; 4138 } 4139 4140 hist_data->save_vars[hist_data->n_save_vars++] = field_var; 4141 if (field_var->val->flags & 4142 (HIST_FIELD_FL_STRING | HIST_FIELD_FL_STACKTRACE)) 4143 hist_data->n_save_var_str++; 4144 kfree(param); 4145 } 4146 } 4147 out: 4148 return ret; 4149 } 4150 4151 static int onmatch_create(struct hist_trigger_data *hist_data, 4152 struct action_data *data) 4153 { 4154 return action_create(hist_data, data); 4155 } 4156 4157 static struct action_data *onmatch_parse(struct trace_array *tr, char *str) 4158 { 4159 char *match_event, *match_event_system; 4160 struct action_data *data; 4161 int ret = -EINVAL; 4162 4163 data = kzalloc(sizeof(*data), GFP_KERNEL); 4164 if (!data) 4165 return ERR_PTR(-ENOMEM); 4166 4167 match_event = strsep(&str, ")"); 4168 if (!match_event || !str) { 4169 hist_err(tr, HIST_ERR_NO_CLOSING_PAREN, errpos(match_event)); 4170 goto free; 4171 } 4172 4173 match_event_system = strsep(&match_event, "."); 4174 if (!match_event) { 4175 hist_err(tr, HIST_ERR_SUBSYS_NOT_FOUND, errpos(match_event_system)); 4176 goto free; 4177 } 4178 4179 if (IS_ERR(event_file(tr, match_event_system, match_event))) { 4180 hist_err(tr, HIST_ERR_INVALID_SUBSYS_EVENT, errpos(match_event)); 4181 goto free; 4182 } 4183 4184 data->match_data.event = kstrdup(match_event, GFP_KERNEL); 4185 if (!data->match_data.event) { 4186 ret = -ENOMEM; 4187 goto free; 4188 } 4189 4190 data->match_data.event_system = kstrdup(match_event_system, GFP_KERNEL); 4191 if (!data->match_data.event_system) { 4192 ret = -ENOMEM; 4193 goto free; 4194 } 4195 4196 ret = action_parse(tr, str, data, HANDLER_ONMATCH); 4197 if (ret) 4198 goto free; 4199 out: 4200 return data; 4201 free: 4202 onmatch_destroy(data); 4203 data = ERR_PTR(ret); 4204 goto out; 4205 } 4206 4207 static int create_hitcount_val(struct hist_trigger_data *hist_data) 4208 { 4209 hist_data->fields[HITCOUNT_IDX] = 4210 create_hist_field(hist_data, NULL, HIST_FIELD_FL_HITCOUNT, NULL); 4211 if (!hist_data->fields[HITCOUNT_IDX]) 4212 return -ENOMEM; 4213 4214 hist_data->n_vals++; 4215 hist_data->n_fields++; 4216 4217 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX)) 4218 return -EINVAL; 4219 4220 return 0; 4221 } 4222 4223 static int __create_val_field(struct hist_trigger_data *hist_data, 4224 unsigned int val_idx, 4225 struct trace_event_file *file, 4226 char *var_name, char *field_str, 4227 unsigned long flags) 4228 { 4229 struct hist_field *hist_field; 4230 int ret = 0, n_subexprs = 0; 4231 4232 hist_field = parse_expr(hist_data, file, field_str, flags, var_name, &n_subexprs); 4233 if (IS_ERR(hist_field)) { 4234 ret = PTR_ERR(hist_field); 4235 goto out; 4236 } 4237 4238 /* values and variables should not have some modifiers */ 4239 if (hist_field->flags & HIST_FIELD_FL_VAR) { 4240 /* Variable */ 4241 if (hist_field->flags & (HIST_FIELD_FL_GRAPH | HIST_FIELD_FL_PERCENT | 4242 HIST_FIELD_FL_BUCKET | HIST_FIELD_FL_LOG2)) 4243 goto err; 4244 } else { 4245 /* Value */ 4246 if (hist_field->flags & (HIST_FIELD_FL_GRAPH | HIST_FIELD_FL_PERCENT | 4247 HIST_FIELD_FL_BUCKET | HIST_FIELD_FL_LOG2 | 4248 HIST_FIELD_FL_SYM | HIST_FIELD_FL_SYM_OFFSET | 4249 HIST_FIELD_FL_SYSCALL | HIST_FIELD_FL_STACKTRACE)) 4250 goto err; 4251 } 4252 4253 hist_data->fields[val_idx] = hist_field; 4254 4255 ++hist_data->n_vals; 4256 ++hist_data->n_fields; 4257 4258 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX)) 4259 ret = -EINVAL; 4260 out: 4261 return ret; 4262 err: 4263 hist_err(file->tr, HIST_ERR_BAD_FIELD_MODIFIER, errpos(field_str)); 4264 return -EINVAL; 4265 } 4266 4267 static int create_val_field(struct hist_trigger_data *hist_data, 4268 unsigned int val_idx, 4269 struct trace_event_file *file, 4270 char *field_str) 4271 { 4272 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX)) 4273 return -EINVAL; 4274 4275 return __create_val_field(hist_data, val_idx, file, NULL, field_str, 0); 4276 } 4277 4278 static const char no_comm[] = "(no comm)"; 4279 4280 static u64 hist_field_execname(struct hist_field *hist_field, 4281 struct tracing_map_elt *elt, 4282 struct trace_buffer *buffer, 4283 struct ring_buffer_event *rbe, 4284 void *event) 4285 { 4286 struct hist_elt_data *elt_data; 4287 4288 if (WARN_ON_ONCE(!elt)) 4289 return (u64)(unsigned long)no_comm; 4290 4291 elt_data = elt->private_data; 4292 4293 if (WARN_ON_ONCE(!elt_data->comm)) 4294 return (u64)(unsigned long)no_comm; 4295 4296 return (u64)(unsigned long)(elt_data->comm); 4297 } 4298 4299 static u64 hist_field_stack(struct hist_field *hist_field, 4300 struct tracing_map_elt *elt, 4301 struct trace_buffer *buffer, 4302 struct ring_buffer_event *rbe, 4303 void *event) 4304 { 4305 u32 str_item = *(u32 *)(event + hist_field->field->offset); 4306 int str_loc = str_item & 0xffff; 4307 char *addr = (char *)(event + str_loc); 4308 4309 return (u64)(unsigned long)addr; 4310 } 4311 4312 static u64 hist_fn_call(struct hist_field *hist_field, 4313 struct tracing_map_elt *elt, 4314 struct trace_buffer *buffer, 4315 struct ring_buffer_event *rbe, 4316 void *event) 4317 { 4318 switch (hist_field->fn_num) { 4319 case HIST_FIELD_FN_VAR_REF: 4320 return hist_field_var_ref(hist_field, elt, buffer, rbe, event); 4321 case HIST_FIELD_FN_COUNTER: 4322 return hist_field_counter(hist_field, elt, buffer, rbe, event); 4323 case HIST_FIELD_FN_CONST: 4324 return hist_field_const(hist_field, elt, buffer, rbe, event); 4325 case HIST_FIELD_FN_LOG2: 4326 return hist_field_log2(hist_field, elt, buffer, rbe, event); 4327 case HIST_FIELD_FN_BUCKET: 4328 return hist_field_bucket(hist_field, elt, buffer, rbe, event); 4329 case HIST_FIELD_FN_TIMESTAMP: 4330 return hist_field_timestamp(hist_field, elt, buffer, rbe, event); 4331 case HIST_FIELD_FN_CPU: 4332 return hist_field_cpu(hist_field, elt, buffer, rbe, event); 4333 case HIST_FIELD_FN_STRING: 4334 return hist_field_string(hist_field, elt, buffer, rbe, event); 4335 case HIST_FIELD_FN_DYNSTRING: 4336 return hist_field_dynstring(hist_field, elt, buffer, rbe, event); 4337 case HIST_FIELD_FN_RELDYNSTRING: 4338 return hist_field_reldynstring(hist_field, elt, buffer, rbe, event); 4339 case HIST_FIELD_FN_PSTRING: 4340 return hist_field_pstring(hist_field, elt, buffer, rbe, event); 4341 case HIST_FIELD_FN_S64: 4342 return hist_field_s64(hist_field, elt, buffer, rbe, event); 4343 case HIST_FIELD_FN_U64: 4344 return hist_field_u64(hist_field, elt, buffer, rbe, event); 4345 case HIST_FIELD_FN_S32: 4346 return hist_field_s32(hist_field, elt, buffer, rbe, event); 4347 case HIST_FIELD_FN_U32: 4348 return hist_field_u32(hist_field, elt, buffer, rbe, event); 4349 case HIST_FIELD_FN_S16: 4350 return hist_field_s16(hist_field, elt, buffer, rbe, event); 4351 case HIST_FIELD_FN_U16: 4352 return hist_field_u16(hist_field, elt, buffer, rbe, event); 4353 case HIST_FIELD_FN_S8: 4354 return hist_field_s8(hist_field, elt, buffer, rbe, event); 4355 case HIST_FIELD_FN_U8: 4356 return hist_field_u8(hist_field, elt, buffer, rbe, event); 4357 case HIST_FIELD_FN_UMINUS: 4358 return hist_field_unary_minus(hist_field, elt, buffer, rbe, event); 4359 case HIST_FIELD_FN_MINUS: 4360 return hist_field_minus(hist_field, elt, buffer, rbe, event); 4361 case HIST_FIELD_FN_PLUS: 4362 return hist_field_plus(hist_field, elt, buffer, rbe, event); 4363 case HIST_FIELD_FN_DIV: 4364 return hist_field_div(hist_field, elt, buffer, rbe, event); 4365 case HIST_FIELD_FN_MULT: 4366 return hist_field_mult(hist_field, elt, buffer, rbe, event); 4367 case HIST_FIELD_FN_DIV_POWER2: 4368 return div_by_power_of_two(hist_field, elt, buffer, rbe, event); 4369 case HIST_FIELD_FN_DIV_NOT_POWER2: 4370 return div_by_not_power_of_two(hist_field, elt, buffer, rbe, event); 4371 case HIST_FIELD_FN_DIV_MULT_SHIFT: 4372 return div_by_mult_and_shift(hist_field, elt, buffer, rbe, event); 4373 case HIST_FIELD_FN_EXECNAME: 4374 return hist_field_execname(hist_field, elt, buffer, rbe, event); 4375 case HIST_FIELD_FN_STACK: 4376 return hist_field_stack(hist_field, elt, buffer, rbe, event); 4377 default: 4378 return 0; 4379 } 4380 } 4381 4382 /* Convert a var that points to common_pid.execname to a string */ 4383 static void update_var_execname(struct hist_field *hist_field) 4384 { 4385 hist_field->flags = HIST_FIELD_FL_STRING | HIST_FIELD_FL_VAR | 4386 HIST_FIELD_FL_EXECNAME; 4387 hist_field->size = MAX_FILTER_STR_VAL; 4388 hist_field->is_signed = 0; 4389 4390 kfree_const(hist_field->type); 4391 hist_field->type = "char[]"; 4392 4393 hist_field->fn_num = HIST_FIELD_FN_EXECNAME; 4394 } 4395 4396 static int create_var_field(struct hist_trigger_data *hist_data, 4397 unsigned int val_idx, 4398 struct trace_event_file *file, 4399 char *var_name, char *expr_str) 4400 { 4401 struct trace_array *tr = hist_data->event_file->tr; 4402 unsigned long flags = 0; 4403 int ret; 4404 4405 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX)) 4406 return -EINVAL; 4407 4408 if (find_var(hist_data, file, var_name) && !hist_data->remove) { 4409 hist_err(tr, HIST_ERR_DUPLICATE_VAR, errpos(var_name)); 4410 return -EINVAL; 4411 } 4412 4413 flags |= HIST_FIELD_FL_VAR; 4414 hist_data->n_vars++; 4415 if (WARN_ON(hist_data->n_vars > TRACING_MAP_VARS_MAX)) 4416 return -EINVAL; 4417 4418 ret = __create_val_field(hist_data, val_idx, file, var_name, expr_str, flags); 4419 4420 if (!ret && hist_data->fields[val_idx]->flags & HIST_FIELD_FL_EXECNAME) 4421 update_var_execname(hist_data->fields[val_idx]); 4422 4423 if (!ret && hist_data->fields[val_idx]->flags & 4424 (HIST_FIELD_FL_STRING | HIST_FIELD_FL_STACKTRACE)) 4425 hist_data->fields[val_idx]->var_str_idx = hist_data->n_var_str++; 4426 4427 return ret; 4428 } 4429 4430 static int create_val_fields(struct hist_trigger_data *hist_data, 4431 struct trace_event_file *file) 4432 { 4433 unsigned int i, j = 1, n_hitcount = 0; 4434 char *fields_str, *field_str; 4435 int ret; 4436 4437 ret = create_hitcount_val(hist_data); 4438 if (ret) 4439 goto out; 4440 4441 fields_str = hist_data->attrs->vals_str; 4442 if (!fields_str) 4443 goto out; 4444 4445 for (i = 0, j = 1; i < TRACING_MAP_VALS_MAX && 4446 j < TRACING_MAP_VALS_MAX; i++) { 4447 field_str = strsep(&fields_str, ","); 4448 if (!field_str) 4449 break; 4450 4451 if (strcmp(field_str, "hitcount") == 0) { 4452 if (!n_hitcount++) 4453 continue; 4454 } 4455 4456 ret = create_val_field(hist_data, j++, file, field_str); 4457 if (ret) 4458 goto out; 4459 } 4460 4461 if (fields_str && (strcmp(fields_str, "hitcount") != 0)) 4462 ret = -EINVAL; 4463 out: 4464 /* There is only raw hitcount but nohitcount suppresses it. */ 4465 if (j == 1 && hist_data->attrs->no_hitcount) { 4466 hist_err(hist_data->event_file->tr, HIST_ERR_NEED_NOHC_VAL, 0); 4467 ret = -ENOENT; 4468 } 4469 4470 return ret; 4471 } 4472 4473 static int create_key_field(struct hist_trigger_data *hist_data, 4474 unsigned int key_idx, 4475 unsigned int key_offset, 4476 struct trace_event_file *file, 4477 char *field_str) 4478 { 4479 struct trace_array *tr = hist_data->event_file->tr; 4480 struct hist_field *hist_field = NULL; 4481 unsigned long flags = 0; 4482 unsigned int key_size; 4483 int ret = 0, n_subexprs = 0; 4484 4485 if (WARN_ON(key_idx >= HIST_FIELDS_MAX)) 4486 return -EINVAL; 4487 4488 flags |= HIST_FIELD_FL_KEY; 4489 4490 if (strcmp(field_str, "stacktrace") == 0) { 4491 flags |= HIST_FIELD_FL_STACKTRACE; 4492 key_size = sizeof(unsigned long) * HIST_STACKTRACE_DEPTH; 4493 hist_field = create_hist_field(hist_data, NULL, flags, NULL); 4494 } else { 4495 hist_field = parse_expr(hist_data, file, field_str, flags, 4496 NULL, &n_subexprs); 4497 if (IS_ERR(hist_field)) { 4498 ret = PTR_ERR(hist_field); 4499 goto out; 4500 } 4501 4502 if (field_has_hist_vars(hist_field, 0)) { 4503 hist_err(tr, HIST_ERR_INVALID_REF_KEY, errpos(field_str)); 4504 destroy_hist_field(hist_field, 0); 4505 ret = -EINVAL; 4506 goto out; 4507 } 4508 4509 key_size = hist_field->size; 4510 } 4511 4512 hist_data->fields[key_idx] = hist_field; 4513 4514 key_size = ALIGN(key_size, sizeof(u64)); 4515 hist_data->fields[key_idx]->size = key_size; 4516 hist_data->fields[key_idx]->offset = key_offset; 4517 4518 hist_data->key_size += key_size; 4519 4520 if (hist_data->key_size > HIST_KEY_SIZE_MAX) { 4521 ret = -EINVAL; 4522 goto out; 4523 } 4524 4525 hist_data->n_keys++; 4526 hist_data->n_fields++; 4527 4528 if (WARN_ON(hist_data->n_keys > TRACING_MAP_KEYS_MAX)) 4529 return -EINVAL; 4530 4531 ret = key_size; 4532 out: 4533 return ret; 4534 } 4535 4536 static int create_key_fields(struct hist_trigger_data *hist_data, 4537 struct trace_event_file *file) 4538 { 4539 unsigned int i, key_offset = 0, n_vals = hist_data->n_vals; 4540 char *fields_str, *field_str; 4541 int ret = -EINVAL; 4542 4543 fields_str = hist_data->attrs->keys_str; 4544 if (!fields_str) 4545 goto out; 4546 4547 for (i = n_vals; i < n_vals + TRACING_MAP_KEYS_MAX; i++) { 4548 field_str = strsep(&fields_str, ","); 4549 if (!field_str) 4550 break; 4551 ret = create_key_field(hist_data, i, key_offset, 4552 file, field_str); 4553 if (ret < 0) 4554 goto out; 4555 key_offset += ret; 4556 } 4557 if (fields_str) { 4558 ret = -EINVAL; 4559 goto out; 4560 } 4561 ret = 0; 4562 out: 4563 return ret; 4564 } 4565 4566 static int create_var_fields(struct hist_trigger_data *hist_data, 4567 struct trace_event_file *file) 4568 { 4569 unsigned int i, j = hist_data->n_vals; 4570 int ret = 0; 4571 4572 unsigned int n_vars = hist_data->attrs->var_defs.n_vars; 4573 4574 for (i = 0; i < n_vars; i++) { 4575 char *var_name = hist_data->attrs->var_defs.name[i]; 4576 char *expr = hist_data->attrs->var_defs.expr[i]; 4577 4578 ret = create_var_field(hist_data, j++, file, var_name, expr); 4579 if (ret) 4580 goto out; 4581 } 4582 out: 4583 return ret; 4584 } 4585 4586 static void free_var_defs(struct hist_trigger_data *hist_data) 4587 { 4588 unsigned int i; 4589 4590 for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) { 4591 kfree(hist_data->attrs->var_defs.name[i]); 4592 kfree(hist_data->attrs->var_defs.expr[i]); 4593 } 4594 4595 hist_data->attrs->var_defs.n_vars = 0; 4596 } 4597 4598 static int parse_var_defs(struct hist_trigger_data *hist_data) 4599 { 4600 struct trace_array *tr = hist_data->event_file->tr; 4601 char *s, *str, *var_name, *field_str; 4602 unsigned int i, j, n_vars = 0; 4603 int ret = 0; 4604 4605 for (i = 0; i < hist_data->attrs->n_assignments; i++) { 4606 str = hist_data->attrs->assignment_str[i]; 4607 for (j = 0; j < TRACING_MAP_VARS_MAX; j++) { 4608 field_str = strsep(&str, ","); 4609 if (!field_str) 4610 break; 4611 4612 var_name = strsep(&field_str, "="); 4613 if (!var_name || !field_str) { 4614 hist_err(tr, HIST_ERR_MALFORMED_ASSIGNMENT, 4615 errpos(var_name)); 4616 ret = -EINVAL; 4617 goto free; 4618 } 4619 4620 if (n_vars == TRACING_MAP_VARS_MAX) { 4621 hist_err(tr, HIST_ERR_TOO_MANY_VARS, errpos(var_name)); 4622 ret = -EINVAL; 4623 goto free; 4624 } 4625 4626 s = kstrdup(var_name, GFP_KERNEL); 4627 if (!s) { 4628 ret = -ENOMEM; 4629 goto free; 4630 } 4631 hist_data->attrs->var_defs.name[n_vars] = s; 4632 4633 s = kstrdup(field_str, GFP_KERNEL); 4634 if (!s) { 4635 kfree(hist_data->attrs->var_defs.name[n_vars]); 4636 hist_data->attrs->var_defs.name[n_vars] = NULL; 4637 ret = -ENOMEM; 4638 goto free; 4639 } 4640 hist_data->attrs->var_defs.expr[n_vars++] = s; 4641 4642 hist_data->attrs->var_defs.n_vars = n_vars; 4643 } 4644 } 4645 4646 return ret; 4647 free: 4648 free_var_defs(hist_data); 4649 4650 return ret; 4651 } 4652 4653 static int create_hist_fields(struct hist_trigger_data *hist_data, 4654 struct trace_event_file *file) 4655 { 4656 int ret; 4657 4658 ret = parse_var_defs(hist_data); 4659 if (ret) 4660 return ret; 4661 4662 ret = create_val_fields(hist_data, file); 4663 if (ret) 4664 goto out; 4665 4666 ret = create_var_fields(hist_data, file); 4667 if (ret) 4668 goto out; 4669 4670 ret = create_key_fields(hist_data, file); 4671 4672 out: 4673 free_var_defs(hist_data); 4674 4675 return ret; 4676 } 4677 4678 static int is_descending(struct trace_array *tr, const char *str) 4679 { 4680 if (!str) 4681 return 0; 4682 4683 if (strcmp(str, "descending") == 0) 4684 return 1; 4685 4686 if (strcmp(str, "ascending") == 0) 4687 return 0; 4688 4689 hist_err(tr, HIST_ERR_INVALID_SORT_MODIFIER, errpos((char *)str)); 4690 4691 return -EINVAL; 4692 } 4693 4694 static int create_sort_keys(struct hist_trigger_data *hist_data) 4695 { 4696 struct trace_array *tr = hist_data->event_file->tr; 4697 char *fields_str = hist_data->attrs->sort_key_str; 4698 struct tracing_map_sort_key *sort_key; 4699 int descending, ret = 0; 4700 unsigned int i, j, k; 4701 4702 hist_data->n_sort_keys = 1; /* we always have at least one, hitcount */ 4703 4704 if (!fields_str) 4705 goto out; 4706 4707 for (i = 0; i < TRACING_MAP_SORT_KEYS_MAX; i++) { 4708 struct hist_field *hist_field; 4709 char *field_str, *field_name; 4710 const char *test_name; 4711 4712 sort_key = &hist_data->sort_keys[i]; 4713 4714 field_str = strsep(&fields_str, ","); 4715 if (!field_str) 4716 break; 4717 4718 if (!*field_str) { 4719 ret = -EINVAL; 4720 hist_err(tr, HIST_ERR_EMPTY_SORT_FIELD, errpos("sort=")); 4721 break; 4722 } 4723 4724 if ((i == TRACING_MAP_SORT_KEYS_MAX - 1) && fields_str) { 4725 hist_err(tr, HIST_ERR_TOO_MANY_SORT_FIELDS, errpos("sort=")); 4726 ret = -EINVAL; 4727 break; 4728 } 4729 4730 field_name = strsep(&field_str, "."); 4731 if (!field_name || !*field_name) { 4732 ret = -EINVAL; 4733 hist_err(tr, HIST_ERR_EMPTY_SORT_FIELD, errpos("sort=")); 4734 break; 4735 } 4736 4737 if (strcmp(field_name, "hitcount") == 0) { 4738 descending = is_descending(tr, field_str); 4739 if (descending < 0) { 4740 ret = descending; 4741 break; 4742 } 4743 sort_key->descending = descending; 4744 continue; 4745 } 4746 4747 for (j = 1, k = 1; j < hist_data->n_fields; j++) { 4748 unsigned int idx; 4749 4750 hist_field = hist_data->fields[j]; 4751 if (hist_field->flags & HIST_FIELD_FL_VAR) 4752 continue; 4753 4754 idx = k++; 4755 4756 test_name = hist_field_name(hist_field, 0); 4757 4758 if (strcmp(field_name, test_name) == 0) { 4759 sort_key->field_idx = idx; 4760 descending = is_descending(tr, field_str); 4761 if (descending < 0) { 4762 ret = descending; 4763 goto out; 4764 } 4765 sort_key->descending = descending; 4766 break; 4767 } 4768 } 4769 if (j == hist_data->n_fields) { 4770 ret = -EINVAL; 4771 hist_err(tr, HIST_ERR_INVALID_SORT_FIELD, errpos(field_name)); 4772 break; 4773 } 4774 } 4775 4776 hist_data->n_sort_keys = i; 4777 out: 4778 return ret; 4779 } 4780 4781 static void destroy_actions(struct hist_trigger_data *hist_data) 4782 { 4783 unsigned int i; 4784 4785 for (i = 0; i < hist_data->n_actions; i++) { 4786 struct action_data *data = hist_data->actions[i]; 4787 4788 if (data->handler == HANDLER_ONMATCH) 4789 onmatch_destroy(data); 4790 else if (data->handler == HANDLER_ONMAX || 4791 data->handler == HANDLER_ONCHANGE) 4792 track_data_destroy(hist_data, data); 4793 else 4794 kfree(data); 4795 } 4796 } 4797 4798 static int parse_actions(struct hist_trigger_data *hist_data) 4799 { 4800 struct trace_array *tr = hist_data->event_file->tr; 4801 struct action_data *data; 4802 unsigned int i; 4803 int ret = 0; 4804 char *str; 4805 int len; 4806 4807 for (i = 0; i < hist_data->attrs->n_actions; i++) { 4808 str = hist_data->attrs->action_str[i]; 4809 4810 if ((len = str_has_prefix(str, "onmatch("))) { 4811 char *action_str = str + len; 4812 4813 data = onmatch_parse(tr, action_str); 4814 if (IS_ERR(data)) { 4815 ret = PTR_ERR(data); 4816 break; 4817 } 4818 } else if ((len = str_has_prefix(str, "onmax("))) { 4819 char *action_str = str + len; 4820 4821 data = track_data_parse(hist_data, action_str, 4822 HANDLER_ONMAX); 4823 if (IS_ERR(data)) { 4824 ret = PTR_ERR(data); 4825 break; 4826 } 4827 } else if ((len = str_has_prefix(str, "onchange("))) { 4828 char *action_str = str + len; 4829 4830 data = track_data_parse(hist_data, action_str, 4831 HANDLER_ONCHANGE); 4832 if (IS_ERR(data)) { 4833 ret = PTR_ERR(data); 4834 break; 4835 } 4836 } else { 4837 ret = -EINVAL; 4838 break; 4839 } 4840 4841 hist_data->actions[hist_data->n_actions++] = data; 4842 } 4843 4844 return ret; 4845 } 4846 4847 static int create_actions(struct hist_trigger_data *hist_data) 4848 { 4849 struct action_data *data; 4850 unsigned int i; 4851 int ret = 0; 4852 4853 for (i = 0; i < hist_data->attrs->n_actions; i++) { 4854 data = hist_data->actions[i]; 4855 4856 if (data->handler == HANDLER_ONMATCH) { 4857 ret = onmatch_create(hist_data, data); 4858 if (ret) 4859 break; 4860 } else if (data->handler == HANDLER_ONMAX || 4861 data->handler == HANDLER_ONCHANGE) { 4862 ret = track_data_create(hist_data, data); 4863 if (ret) 4864 break; 4865 } else { 4866 ret = -EINVAL; 4867 break; 4868 } 4869 } 4870 4871 return ret; 4872 } 4873 4874 static void print_actions(struct seq_file *m, 4875 struct hist_trigger_data *hist_data, 4876 struct tracing_map_elt *elt) 4877 { 4878 unsigned int i; 4879 4880 for (i = 0; i < hist_data->n_actions; i++) { 4881 struct action_data *data = hist_data->actions[i]; 4882 4883 if (data->action == ACTION_SNAPSHOT) 4884 continue; 4885 4886 if (data->handler == HANDLER_ONMAX || 4887 data->handler == HANDLER_ONCHANGE) 4888 track_data_print(m, hist_data, elt, data); 4889 } 4890 } 4891 4892 static void print_action_spec(struct seq_file *m, 4893 struct hist_trigger_data *hist_data, 4894 struct action_data *data) 4895 { 4896 unsigned int i; 4897 4898 if (data->action == ACTION_SAVE) { 4899 for (i = 0; i < hist_data->n_save_vars; i++) { 4900 seq_printf(m, "%s", hist_data->save_vars[i]->var->var.name); 4901 if (i < hist_data->n_save_vars - 1) 4902 seq_puts(m, ","); 4903 } 4904 } else if (data->action == ACTION_TRACE) { 4905 if (data->use_trace_keyword) 4906 seq_printf(m, "%s", data->synth_event_name); 4907 for (i = 0; i < data->n_params; i++) { 4908 if (i || data->use_trace_keyword) 4909 seq_puts(m, ","); 4910 seq_printf(m, "%s", data->params[i]); 4911 } 4912 } 4913 } 4914 4915 static void print_track_data_spec(struct seq_file *m, 4916 struct hist_trigger_data *hist_data, 4917 struct action_data *data) 4918 { 4919 if (data->handler == HANDLER_ONMAX) 4920 seq_puts(m, ":onmax("); 4921 else if (data->handler == HANDLER_ONCHANGE) 4922 seq_puts(m, ":onchange("); 4923 seq_printf(m, "%s", data->track_data.var_str); 4924 seq_printf(m, ").%s(", data->action_name); 4925 4926 print_action_spec(m, hist_data, data); 4927 4928 seq_puts(m, ")"); 4929 } 4930 4931 static void print_onmatch_spec(struct seq_file *m, 4932 struct hist_trigger_data *hist_data, 4933 struct action_data *data) 4934 { 4935 seq_printf(m, ":onmatch(%s.%s).", data->match_data.event_system, 4936 data->match_data.event); 4937 4938 seq_printf(m, "%s(", data->action_name); 4939 4940 print_action_spec(m, hist_data, data); 4941 4942 seq_puts(m, ")"); 4943 } 4944 4945 static bool actions_match(struct hist_trigger_data *hist_data, 4946 struct hist_trigger_data *hist_data_test) 4947 { 4948 unsigned int i, j; 4949 4950 if (hist_data->n_actions != hist_data_test->n_actions) 4951 return false; 4952 4953 for (i = 0; i < hist_data->n_actions; i++) { 4954 struct action_data *data = hist_data->actions[i]; 4955 struct action_data *data_test = hist_data_test->actions[i]; 4956 char *action_name, *action_name_test; 4957 4958 if (data->handler != data_test->handler) 4959 return false; 4960 if (data->action != data_test->action) 4961 return false; 4962 4963 if (data->n_params != data_test->n_params) 4964 return false; 4965 4966 for (j = 0; j < data->n_params; j++) { 4967 if (strcmp(data->params[j], data_test->params[j]) != 0) 4968 return false; 4969 } 4970 4971 if (data->use_trace_keyword) 4972 action_name = data->synth_event_name; 4973 else 4974 action_name = data->action_name; 4975 4976 if (data_test->use_trace_keyword) 4977 action_name_test = data_test->synth_event_name; 4978 else 4979 action_name_test = data_test->action_name; 4980 4981 if (strcmp(action_name, action_name_test) != 0) 4982 return false; 4983 4984 if (data->handler == HANDLER_ONMATCH) { 4985 if (strcmp(data->match_data.event_system, 4986 data_test->match_data.event_system) != 0) 4987 return false; 4988 if (strcmp(data->match_data.event, 4989 data_test->match_data.event) != 0) 4990 return false; 4991 } else if (data->handler == HANDLER_ONMAX || 4992 data->handler == HANDLER_ONCHANGE) { 4993 if (strcmp(data->track_data.var_str, 4994 data_test->track_data.var_str) != 0) 4995 return false; 4996 } 4997 } 4998 4999 return true; 5000 } 5001 5002 5003 static void print_actions_spec(struct seq_file *m, 5004 struct hist_trigger_data *hist_data) 5005 { 5006 unsigned int i; 5007 5008 for (i = 0; i < hist_data->n_actions; i++) { 5009 struct action_data *data = hist_data->actions[i]; 5010 5011 if (data->handler == HANDLER_ONMATCH) 5012 print_onmatch_spec(m, hist_data, data); 5013 else if (data->handler == HANDLER_ONMAX || 5014 data->handler == HANDLER_ONCHANGE) 5015 print_track_data_spec(m, hist_data, data); 5016 } 5017 } 5018 5019 static void destroy_field_var_hists(struct hist_trigger_data *hist_data) 5020 { 5021 unsigned int i; 5022 5023 for (i = 0; i < hist_data->n_field_var_hists; i++) { 5024 kfree(hist_data->field_var_hists[i]->cmd); 5025 kfree(hist_data->field_var_hists[i]); 5026 } 5027 } 5028 5029 static void destroy_hist_data(struct hist_trigger_data *hist_data) 5030 { 5031 if (!hist_data) 5032 return; 5033 5034 destroy_hist_trigger_attrs(hist_data->attrs); 5035 destroy_hist_fields(hist_data); 5036 tracing_map_destroy(hist_data->map); 5037 5038 destroy_actions(hist_data); 5039 destroy_field_vars(hist_data); 5040 destroy_field_var_hists(hist_data); 5041 5042 kfree(hist_data); 5043 } 5044 5045 static int create_tracing_map_fields(struct hist_trigger_data *hist_data) 5046 { 5047 struct tracing_map *map = hist_data->map; 5048 struct ftrace_event_field *field; 5049 struct hist_field *hist_field; 5050 int i, idx = 0; 5051 5052 for_each_hist_field(i, hist_data) { 5053 hist_field = hist_data->fields[i]; 5054 if (hist_field->flags & HIST_FIELD_FL_KEY) { 5055 tracing_map_cmp_fn_t cmp_fn; 5056 5057 field = hist_field->field; 5058 5059 if (hist_field->flags & HIST_FIELD_FL_STACKTRACE) 5060 cmp_fn = tracing_map_cmp_none; 5061 else if (!field || hist_field->flags & HIST_FIELD_FL_CPU) 5062 cmp_fn = tracing_map_cmp_num(hist_field->size, 5063 hist_field->is_signed); 5064 else if (is_string_field(field)) 5065 cmp_fn = tracing_map_cmp_string; 5066 else 5067 cmp_fn = tracing_map_cmp_num(field->size, 5068 field->is_signed); 5069 idx = tracing_map_add_key_field(map, 5070 hist_field->offset, 5071 cmp_fn); 5072 } else if (!(hist_field->flags & HIST_FIELD_FL_VAR)) 5073 idx = tracing_map_add_sum_field(map); 5074 5075 if (idx < 0) 5076 return idx; 5077 5078 if (hist_field->flags & HIST_FIELD_FL_VAR) { 5079 idx = tracing_map_add_var(map); 5080 if (idx < 0) 5081 return idx; 5082 hist_field->var.idx = idx; 5083 hist_field->var.hist_data = hist_data; 5084 } 5085 } 5086 5087 return 0; 5088 } 5089 5090 static struct hist_trigger_data * 5091 create_hist_data(unsigned int map_bits, 5092 struct hist_trigger_attrs *attrs, 5093 struct trace_event_file *file, 5094 bool remove) 5095 { 5096 const struct tracing_map_ops *map_ops = NULL; 5097 struct hist_trigger_data *hist_data; 5098 int ret = 0; 5099 5100 hist_data = kzalloc(sizeof(*hist_data), GFP_KERNEL); 5101 if (!hist_data) 5102 return ERR_PTR(-ENOMEM); 5103 5104 hist_data->attrs = attrs; 5105 hist_data->remove = remove; 5106 hist_data->event_file = file; 5107 5108 ret = parse_actions(hist_data); 5109 if (ret) 5110 goto free; 5111 5112 ret = create_hist_fields(hist_data, file); 5113 if (ret) 5114 goto free; 5115 5116 ret = create_sort_keys(hist_data); 5117 if (ret) 5118 goto free; 5119 5120 map_ops = &hist_trigger_elt_data_ops; 5121 5122 hist_data->map = tracing_map_create(map_bits, hist_data->key_size, 5123 map_ops, hist_data); 5124 if (IS_ERR(hist_data->map)) { 5125 ret = PTR_ERR(hist_data->map); 5126 hist_data->map = NULL; 5127 goto free; 5128 } 5129 5130 ret = create_tracing_map_fields(hist_data); 5131 if (ret) 5132 goto free; 5133 out: 5134 return hist_data; 5135 free: 5136 hist_data->attrs = NULL; 5137 5138 destroy_hist_data(hist_data); 5139 5140 hist_data = ERR_PTR(ret); 5141 5142 goto out; 5143 } 5144 5145 static void hist_trigger_elt_update(struct hist_trigger_data *hist_data, 5146 struct tracing_map_elt *elt, 5147 struct trace_buffer *buffer, void *rec, 5148 struct ring_buffer_event *rbe, 5149 u64 *var_ref_vals) 5150 { 5151 struct hist_elt_data *elt_data; 5152 struct hist_field *hist_field; 5153 unsigned int i, var_idx; 5154 u64 hist_val; 5155 5156 elt_data = elt->private_data; 5157 elt_data->var_ref_vals = var_ref_vals; 5158 5159 for_each_hist_val_field(i, hist_data) { 5160 hist_field = hist_data->fields[i]; 5161 hist_val = hist_fn_call(hist_field, elt, buffer, rbe, rec); 5162 if (hist_field->flags & HIST_FIELD_FL_VAR) { 5163 var_idx = hist_field->var.idx; 5164 5165 if (hist_field->flags & 5166 (HIST_FIELD_FL_STRING | HIST_FIELD_FL_STACKTRACE)) { 5167 unsigned int str_start, var_str_idx, idx; 5168 char *str, *val_str; 5169 unsigned int size; 5170 5171 str_start = hist_data->n_field_var_str + 5172 hist_data->n_save_var_str; 5173 var_str_idx = hist_field->var_str_idx; 5174 idx = str_start + var_str_idx; 5175 5176 str = elt_data->field_var_str[idx]; 5177 val_str = (char *)(uintptr_t)hist_val; 5178 5179 if (hist_field->flags & HIST_FIELD_FL_STRING) { 5180 size = min(hist_field->size, STR_VAR_LEN_MAX); 5181 strscpy(str, val_str, size); 5182 } else { 5183 char *stack_start = str + sizeof(unsigned long); 5184 int e; 5185 5186 e = stack_trace_save((void *)stack_start, 5187 HIST_STACKTRACE_DEPTH, 5188 HIST_STACKTRACE_SKIP); 5189 if (e < HIST_STACKTRACE_DEPTH - 1) 5190 ((unsigned long *)stack_start)[e] = 0; 5191 *((unsigned long *)str) = e; 5192 } 5193 hist_val = (u64)(uintptr_t)str; 5194 } 5195 tracing_map_set_var(elt, var_idx, hist_val); 5196 continue; 5197 } 5198 tracing_map_update_sum(elt, i, hist_val); 5199 } 5200 5201 for_each_hist_key_field(i, hist_data) { 5202 hist_field = hist_data->fields[i]; 5203 if (hist_field->flags & HIST_FIELD_FL_VAR) { 5204 hist_val = hist_fn_call(hist_field, elt, buffer, rbe, rec); 5205 var_idx = hist_field->var.idx; 5206 tracing_map_set_var(elt, var_idx, hist_val); 5207 } 5208 } 5209 5210 update_field_vars(hist_data, elt, buffer, rbe, rec); 5211 } 5212 5213 static inline void add_to_key(char *compound_key, void *key, 5214 struct hist_field *key_field, void *rec) 5215 { 5216 size_t size = key_field->size; 5217 5218 if (key_field->flags & HIST_FIELD_FL_STRING) { 5219 struct ftrace_event_field *field; 5220 5221 field = key_field->field; 5222 if (field->filter_type == FILTER_DYN_STRING || 5223 field->filter_type == FILTER_RDYN_STRING) 5224 size = *(u32 *)(rec + field->offset) >> 16; 5225 else if (field->filter_type == FILTER_STATIC_STRING) 5226 size = field->size; 5227 5228 /* ensure NULL-termination */ 5229 if (size > key_field->size - 1) 5230 size = key_field->size - 1; 5231 5232 strncpy(compound_key + key_field->offset, (char *)key, size); 5233 } else 5234 memcpy(compound_key + key_field->offset, key, size); 5235 } 5236 5237 static void 5238 hist_trigger_actions(struct hist_trigger_data *hist_data, 5239 struct tracing_map_elt *elt, 5240 struct trace_buffer *buffer, void *rec, 5241 struct ring_buffer_event *rbe, void *key, 5242 u64 *var_ref_vals) 5243 { 5244 struct action_data *data; 5245 unsigned int i; 5246 5247 for (i = 0; i < hist_data->n_actions; i++) { 5248 data = hist_data->actions[i]; 5249 data->fn(hist_data, elt, buffer, rec, rbe, key, data, var_ref_vals); 5250 } 5251 } 5252 5253 static void event_hist_trigger(struct event_trigger_data *data, 5254 struct trace_buffer *buffer, void *rec, 5255 struct ring_buffer_event *rbe) 5256 { 5257 struct hist_trigger_data *hist_data = data->private_data; 5258 bool use_compound_key = (hist_data->n_keys > 1); 5259 unsigned long entries[HIST_STACKTRACE_DEPTH]; 5260 u64 var_ref_vals[TRACING_MAP_VARS_MAX]; 5261 char compound_key[HIST_KEY_SIZE_MAX]; 5262 struct tracing_map_elt *elt = NULL; 5263 struct hist_field *key_field; 5264 u64 field_contents; 5265 void *key = NULL; 5266 unsigned int i; 5267 5268 if (unlikely(!rbe)) 5269 return; 5270 5271 memset(compound_key, 0, hist_data->key_size); 5272 5273 for_each_hist_key_field(i, hist_data) { 5274 key_field = hist_data->fields[i]; 5275 5276 if (key_field->flags & HIST_FIELD_FL_STACKTRACE) { 5277 memset(entries, 0, HIST_STACKTRACE_SIZE); 5278 if (key_field->field) { 5279 unsigned long *stack, n_entries; 5280 5281 field_contents = hist_fn_call(key_field, elt, buffer, rbe, rec); 5282 stack = (unsigned long *)(long)field_contents; 5283 n_entries = *stack; 5284 memcpy(entries, ++stack, n_entries * sizeof(unsigned long)); 5285 } else { 5286 stack_trace_save(entries, HIST_STACKTRACE_DEPTH, 5287 HIST_STACKTRACE_SKIP); 5288 } 5289 key = entries; 5290 } else { 5291 field_contents = hist_fn_call(key_field, elt, buffer, rbe, rec); 5292 if (key_field->flags & HIST_FIELD_FL_STRING) { 5293 key = (void *)(unsigned long)field_contents; 5294 use_compound_key = true; 5295 } else 5296 key = (void *)&field_contents; 5297 } 5298 5299 if (use_compound_key) 5300 add_to_key(compound_key, key, key_field, rec); 5301 } 5302 5303 if (use_compound_key) 5304 key = compound_key; 5305 5306 if (hist_data->n_var_refs && 5307 !resolve_var_refs(hist_data, key, var_ref_vals, false)) 5308 return; 5309 5310 elt = tracing_map_insert(hist_data->map, key); 5311 if (!elt) 5312 return; 5313 5314 hist_trigger_elt_update(hist_data, elt, buffer, rec, rbe, var_ref_vals); 5315 5316 if (resolve_var_refs(hist_data, key, var_ref_vals, true)) 5317 hist_trigger_actions(hist_data, elt, buffer, rec, rbe, key, var_ref_vals); 5318 } 5319 5320 static void hist_trigger_stacktrace_print(struct seq_file *m, 5321 unsigned long *stacktrace_entries, 5322 unsigned int max_entries) 5323 { 5324 unsigned int spaces = 8; 5325 unsigned int i; 5326 5327 for (i = 0; i < max_entries; i++) { 5328 if (!stacktrace_entries[i]) 5329 return; 5330 5331 seq_printf(m, "%*c", 1 + spaces, ' '); 5332 seq_printf(m, "%pS\n", (void*)stacktrace_entries[i]); 5333 } 5334 } 5335 5336 static void hist_trigger_print_key(struct seq_file *m, 5337 struct hist_trigger_data *hist_data, 5338 void *key, 5339 struct tracing_map_elt *elt) 5340 { 5341 struct hist_field *key_field; 5342 bool multiline = false; 5343 const char *field_name; 5344 unsigned int i; 5345 u64 uval; 5346 5347 seq_puts(m, "{ "); 5348 5349 for_each_hist_key_field(i, hist_data) { 5350 key_field = hist_data->fields[i]; 5351 5352 if (i > hist_data->n_vals) 5353 seq_puts(m, ", "); 5354 5355 field_name = hist_field_name(key_field, 0); 5356 5357 if (key_field->flags & HIST_FIELD_FL_HEX) { 5358 uval = *(u64 *)(key + key_field->offset); 5359 seq_printf(m, "%s: %llx", field_name, uval); 5360 } else if (key_field->flags & HIST_FIELD_FL_SYM) { 5361 uval = *(u64 *)(key + key_field->offset); 5362 seq_printf(m, "%s: [%llx] %-45ps", field_name, 5363 uval, (void *)(uintptr_t)uval); 5364 } else if (key_field->flags & HIST_FIELD_FL_SYM_OFFSET) { 5365 uval = *(u64 *)(key + key_field->offset); 5366 seq_printf(m, "%s: [%llx] %-55pS", field_name, 5367 uval, (void *)(uintptr_t)uval); 5368 } else if (key_field->flags & HIST_FIELD_FL_EXECNAME) { 5369 struct hist_elt_data *elt_data = elt->private_data; 5370 char *comm; 5371 5372 if (WARN_ON_ONCE(!elt_data)) 5373 return; 5374 5375 comm = elt_data->comm; 5376 5377 uval = *(u64 *)(key + key_field->offset); 5378 seq_printf(m, "%s: %-16s[%10llu]", field_name, 5379 comm, uval); 5380 } else if (key_field->flags & HIST_FIELD_FL_SYSCALL) { 5381 const char *syscall_name; 5382 5383 uval = *(u64 *)(key + key_field->offset); 5384 syscall_name = get_syscall_name(uval); 5385 if (!syscall_name) 5386 syscall_name = "unknown_syscall"; 5387 5388 seq_printf(m, "%s: %-30s[%3llu]", field_name, 5389 syscall_name, uval); 5390 } else if (key_field->flags & HIST_FIELD_FL_STACKTRACE) { 5391 if (key_field->field) 5392 seq_printf(m, "%s.stacktrace", key_field->field->name); 5393 else 5394 seq_puts(m, "common_stacktrace:\n"); 5395 hist_trigger_stacktrace_print(m, 5396 key + key_field->offset, 5397 HIST_STACKTRACE_DEPTH); 5398 multiline = true; 5399 } else if (key_field->flags & HIST_FIELD_FL_LOG2) { 5400 seq_printf(m, "%s: ~ 2^%-2llu", field_name, 5401 *(u64 *)(key + key_field->offset)); 5402 } else if (key_field->flags & HIST_FIELD_FL_BUCKET) { 5403 unsigned long buckets = key_field->buckets; 5404 uval = *(u64 *)(key + key_field->offset); 5405 seq_printf(m, "%s: ~ %llu-%llu", field_name, 5406 uval, uval + buckets -1); 5407 } else if (key_field->flags & HIST_FIELD_FL_STRING) { 5408 seq_printf(m, "%s: %-50s", field_name, 5409 (char *)(key + key_field->offset)); 5410 } else { 5411 uval = *(u64 *)(key + key_field->offset); 5412 seq_printf(m, "%s: %10llu", field_name, uval); 5413 } 5414 } 5415 5416 if (!multiline) 5417 seq_puts(m, " "); 5418 5419 seq_puts(m, "}"); 5420 } 5421 5422 /* Get the 100 times of the percentage of @val in @total */ 5423 static inline unsigned int __get_percentage(u64 val, u64 total) 5424 { 5425 if (!total) 5426 goto div0; 5427 5428 if (val < (U64_MAX / 10000)) 5429 return (unsigned int)div64_ul(val * 10000, total); 5430 5431 total = div64_u64(total, 10000); 5432 if (!total) 5433 goto div0; 5434 5435 return (unsigned int)div64_ul(val, total); 5436 div0: 5437 return val ? UINT_MAX : 0; 5438 } 5439 5440 #define BAR_CHAR '#' 5441 5442 static inline const char *__fill_bar_str(char *buf, int size, u64 val, u64 max) 5443 { 5444 unsigned int len = __get_percentage(val, max); 5445 int i; 5446 5447 if (len == UINT_MAX) { 5448 snprintf(buf, size, "[ERROR]"); 5449 return buf; 5450 } 5451 5452 len = len * size / 10000; 5453 for (i = 0; i < len && i < size; i++) 5454 buf[i] = BAR_CHAR; 5455 while (i < size) 5456 buf[i++] = ' '; 5457 buf[size] = '\0'; 5458 5459 return buf; 5460 } 5461 5462 struct hist_val_stat { 5463 u64 max; 5464 u64 total; 5465 }; 5466 5467 static void hist_trigger_print_val(struct seq_file *m, unsigned int idx, 5468 const char *field_name, unsigned long flags, 5469 struct hist_val_stat *stats, 5470 struct tracing_map_elt *elt) 5471 { 5472 u64 val = tracing_map_read_sum(elt, idx); 5473 unsigned int pc; 5474 char bar[21]; 5475 5476 if (flags & HIST_FIELD_FL_PERCENT) { 5477 pc = __get_percentage(val, stats[idx].total); 5478 if (pc == UINT_MAX) 5479 seq_printf(m, " %s (%%):[ERROR]", field_name); 5480 else 5481 seq_printf(m, " %s (%%): %3u.%02u", field_name, 5482 pc / 100, pc % 100); 5483 } else if (flags & HIST_FIELD_FL_GRAPH) { 5484 seq_printf(m, " %s: %20s", field_name, 5485 __fill_bar_str(bar, 20, val, stats[idx].max)); 5486 } else if (flags & HIST_FIELD_FL_HEX) { 5487 seq_printf(m, " %s: %10llx", field_name, val); 5488 } else { 5489 seq_printf(m, " %s: %10llu", field_name, val); 5490 } 5491 } 5492 5493 static void hist_trigger_entry_print(struct seq_file *m, 5494 struct hist_trigger_data *hist_data, 5495 struct hist_val_stat *stats, 5496 void *key, 5497 struct tracing_map_elt *elt) 5498 { 5499 const char *field_name; 5500 unsigned int i = HITCOUNT_IDX; 5501 unsigned long flags; 5502 5503 hist_trigger_print_key(m, hist_data, key, elt); 5504 5505 /* At first, show the raw hitcount if !nohitcount */ 5506 if (!hist_data->attrs->no_hitcount) 5507 hist_trigger_print_val(m, i, "hitcount", 0, stats, elt); 5508 5509 for (i = 1; i < hist_data->n_vals; i++) { 5510 field_name = hist_field_name(hist_data->fields[i], 0); 5511 flags = hist_data->fields[i]->flags; 5512 if (flags & HIST_FIELD_FL_VAR || flags & HIST_FIELD_FL_EXPR) 5513 continue; 5514 5515 seq_puts(m, " "); 5516 hist_trigger_print_val(m, i, field_name, flags, stats, elt); 5517 } 5518 5519 print_actions(m, hist_data, elt); 5520 5521 seq_puts(m, "\n"); 5522 } 5523 5524 static int print_entries(struct seq_file *m, 5525 struct hist_trigger_data *hist_data) 5526 { 5527 struct tracing_map_sort_entry **sort_entries = NULL; 5528 struct tracing_map *map = hist_data->map; 5529 int i, j, n_entries; 5530 struct hist_val_stat *stats = NULL; 5531 u64 val; 5532 5533 n_entries = tracing_map_sort_entries(map, hist_data->sort_keys, 5534 hist_data->n_sort_keys, 5535 &sort_entries); 5536 if (n_entries < 0) 5537 return n_entries; 5538 5539 /* Calculate the max and the total for each field if needed. */ 5540 for (j = 0; j < hist_data->n_vals; j++) { 5541 if (!(hist_data->fields[j]->flags & 5542 (HIST_FIELD_FL_PERCENT | HIST_FIELD_FL_GRAPH))) 5543 continue; 5544 if (!stats) { 5545 stats = kcalloc(hist_data->n_vals, sizeof(*stats), 5546 GFP_KERNEL); 5547 if (!stats) { 5548 n_entries = -ENOMEM; 5549 goto out; 5550 } 5551 } 5552 for (i = 0; i < n_entries; i++) { 5553 val = tracing_map_read_sum(sort_entries[i]->elt, j); 5554 stats[j].total += val; 5555 if (stats[j].max < val) 5556 stats[j].max = val; 5557 } 5558 } 5559 5560 for (i = 0; i < n_entries; i++) 5561 hist_trigger_entry_print(m, hist_data, stats, 5562 sort_entries[i]->key, 5563 sort_entries[i]->elt); 5564 5565 kfree(stats); 5566 out: 5567 tracing_map_destroy_sort_entries(sort_entries, n_entries); 5568 5569 return n_entries; 5570 } 5571 5572 static void hist_trigger_show(struct seq_file *m, 5573 struct event_trigger_data *data, int n) 5574 { 5575 struct hist_trigger_data *hist_data; 5576 int n_entries; 5577 5578 if (n > 0) 5579 seq_puts(m, "\n\n"); 5580 5581 seq_puts(m, "# event histogram\n#\n# trigger info: "); 5582 data->ops->print(m, data); 5583 seq_puts(m, "#\n\n"); 5584 5585 hist_data = data->private_data; 5586 n_entries = print_entries(m, hist_data); 5587 if (n_entries < 0) 5588 n_entries = 0; 5589 5590 track_data_snapshot_print(m, hist_data); 5591 5592 seq_printf(m, "\nTotals:\n Hits: %llu\n Entries: %u\n Dropped: %llu\n", 5593 (u64)atomic64_read(&hist_data->map->hits), 5594 n_entries, (u64)atomic64_read(&hist_data->map->drops)); 5595 } 5596 5597 static int hist_show(struct seq_file *m, void *v) 5598 { 5599 struct event_trigger_data *data; 5600 struct trace_event_file *event_file; 5601 int n = 0, ret = 0; 5602 5603 mutex_lock(&event_mutex); 5604 5605 event_file = event_file_data(m->private); 5606 if (unlikely(!event_file)) { 5607 ret = -ENODEV; 5608 goto out_unlock; 5609 } 5610 5611 list_for_each_entry(data, &event_file->triggers, list) { 5612 if (data->cmd_ops->trigger_type == ETT_EVENT_HIST) 5613 hist_trigger_show(m, data, n++); 5614 } 5615 5616 out_unlock: 5617 mutex_unlock(&event_mutex); 5618 5619 return ret; 5620 } 5621 5622 static int event_hist_open(struct inode *inode, struct file *file) 5623 { 5624 int ret; 5625 5626 ret = security_locked_down(LOCKDOWN_TRACEFS); 5627 if (ret) 5628 return ret; 5629 5630 return single_open(file, hist_show, file); 5631 } 5632 5633 const struct file_operations event_hist_fops = { 5634 .open = event_hist_open, 5635 .read = seq_read, 5636 .llseek = seq_lseek, 5637 .release = single_release, 5638 }; 5639 5640 #ifdef CONFIG_HIST_TRIGGERS_DEBUG 5641 static void hist_field_debug_show_flags(struct seq_file *m, 5642 unsigned long flags) 5643 { 5644 seq_puts(m, " flags:\n"); 5645 5646 if (flags & HIST_FIELD_FL_KEY) 5647 seq_puts(m, " HIST_FIELD_FL_KEY\n"); 5648 else if (flags & HIST_FIELD_FL_HITCOUNT) 5649 seq_puts(m, " VAL: HIST_FIELD_FL_HITCOUNT\n"); 5650 else if (flags & HIST_FIELD_FL_VAR) 5651 seq_puts(m, " HIST_FIELD_FL_VAR\n"); 5652 else if (flags & HIST_FIELD_FL_VAR_REF) 5653 seq_puts(m, " HIST_FIELD_FL_VAR_REF\n"); 5654 else 5655 seq_puts(m, " VAL: normal u64 value\n"); 5656 5657 if (flags & HIST_FIELD_FL_ALIAS) 5658 seq_puts(m, " HIST_FIELD_FL_ALIAS\n"); 5659 else if (flags & HIST_FIELD_FL_CONST) 5660 seq_puts(m, " HIST_FIELD_FL_CONST\n"); 5661 } 5662 5663 static int hist_field_debug_show(struct seq_file *m, 5664 struct hist_field *field, unsigned long flags) 5665 { 5666 if ((field->flags & flags) != flags) { 5667 seq_printf(m, "ERROR: bad flags - %lx\n", flags); 5668 return -EINVAL; 5669 } 5670 5671 hist_field_debug_show_flags(m, field->flags); 5672 if (field->field) 5673 seq_printf(m, " ftrace_event_field name: %s\n", 5674 field->field->name); 5675 5676 if (field->flags & HIST_FIELD_FL_VAR) { 5677 seq_printf(m, " var.name: %s\n", field->var.name); 5678 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n", 5679 field->var.idx); 5680 } 5681 5682 if (field->flags & HIST_FIELD_FL_CONST) 5683 seq_printf(m, " constant: %llu\n", field->constant); 5684 5685 if (field->flags & HIST_FIELD_FL_ALIAS) 5686 seq_printf(m, " var_ref_idx (into hist_data->var_refs[]): %u\n", 5687 field->var_ref_idx); 5688 5689 if (field->flags & HIST_FIELD_FL_VAR_REF) { 5690 seq_printf(m, " name: %s\n", field->name); 5691 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n", 5692 field->var.idx); 5693 seq_printf(m, " var.hist_data: %p\n", field->var.hist_data); 5694 seq_printf(m, " var_ref_idx (into hist_data->var_refs[]): %u\n", 5695 field->var_ref_idx); 5696 if (field->system) 5697 seq_printf(m, " system: %s\n", field->system); 5698 if (field->event_name) 5699 seq_printf(m, " event_name: %s\n", field->event_name); 5700 } 5701 5702 seq_printf(m, " type: %s\n", field->type); 5703 seq_printf(m, " size: %u\n", field->size); 5704 seq_printf(m, " is_signed: %u\n", field->is_signed); 5705 5706 return 0; 5707 } 5708 5709 static int field_var_debug_show(struct seq_file *m, 5710 struct field_var *field_var, unsigned int i, 5711 bool save_vars) 5712 { 5713 const char *vars_name = save_vars ? "save_vars" : "field_vars"; 5714 struct hist_field *field; 5715 int ret = 0; 5716 5717 seq_printf(m, "\n hist_data->%s[%d]:\n", vars_name, i); 5718 5719 field = field_var->var; 5720 5721 seq_printf(m, "\n %s[%d].var:\n", vars_name, i); 5722 5723 hist_field_debug_show_flags(m, field->flags); 5724 seq_printf(m, " var.name: %s\n", field->var.name); 5725 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n", 5726 field->var.idx); 5727 5728 field = field_var->val; 5729 5730 seq_printf(m, "\n %s[%d].val:\n", vars_name, i); 5731 if (field->field) 5732 seq_printf(m, " ftrace_event_field name: %s\n", 5733 field->field->name); 5734 else { 5735 ret = -EINVAL; 5736 goto out; 5737 } 5738 5739 seq_printf(m, " type: %s\n", field->type); 5740 seq_printf(m, " size: %u\n", field->size); 5741 seq_printf(m, " is_signed: %u\n", field->is_signed); 5742 out: 5743 return ret; 5744 } 5745 5746 static int hist_action_debug_show(struct seq_file *m, 5747 struct action_data *data, int i) 5748 { 5749 int ret = 0; 5750 5751 if (data->handler == HANDLER_ONMAX || 5752 data->handler == HANDLER_ONCHANGE) { 5753 seq_printf(m, "\n hist_data->actions[%d].track_data.var_ref:\n", i); 5754 ret = hist_field_debug_show(m, data->track_data.var_ref, 5755 HIST_FIELD_FL_VAR_REF); 5756 if (ret) 5757 goto out; 5758 5759 seq_printf(m, "\n hist_data->actions[%d].track_data.track_var:\n", i); 5760 ret = hist_field_debug_show(m, data->track_data.track_var, 5761 HIST_FIELD_FL_VAR); 5762 if (ret) 5763 goto out; 5764 } 5765 5766 if (data->handler == HANDLER_ONMATCH) { 5767 seq_printf(m, "\n hist_data->actions[%d].match_data.event_system: %s\n", 5768 i, data->match_data.event_system); 5769 seq_printf(m, " hist_data->actions[%d].match_data.event: %s\n", 5770 i, data->match_data.event); 5771 } 5772 out: 5773 return ret; 5774 } 5775 5776 static int hist_actions_debug_show(struct seq_file *m, 5777 struct hist_trigger_data *hist_data) 5778 { 5779 int i, ret = 0; 5780 5781 if (hist_data->n_actions) 5782 seq_puts(m, "\n action tracking variables (for onmax()/onchange()/onmatch()):\n"); 5783 5784 for (i = 0; i < hist_data->n_actions; i++) { 5785 struct action_data *action = hist_data->actions[i]; 5786 5787 ret = hist_action_debug_show(m, action, i); 5788 if (ret) 5789 goto out; 5790 } 5791 5792 if (hist_data->n_save_vars) 5793 seq_puts(m, "\n save action variables (save() params):\n"); 5794 5795 for (i = 0; i < hist_data->n_save_vars; i++) { 5796 ret = field_var_debug_show(m, hist_data->save_vars[i], i, true); 5797 if (ret) 5798 goto out; 5799 } 5800 out: 5801 return ret; 5802 } 5803 5804 static void hist_trigger_debug_show(struct seq_file *m, 5805 struct event_trigger_data *data, int n) 5806 { 5807 struct hist_trigger_data *hist_data; 5808 int i, ret; 5809 5810 if (n > 0) 5811 seq_puts(m, "\n\n"); 5812 5813 seq_puts(m, "# event histogram\n#\n# trigger info: "); 5814 data->ops->print(m, data); 5815 seq_puts(m, "#\n\n"); 5816 5817 hist_data = data->private_data; 5818 5819 seq_printf(m, "hist_data: %p\n\n", hist_data); 5820 seq_printf(m, " n_vals: %u\n", hist_data->n_vals); 5821 seq_printf(m, " n_keys: %u\n", hist_data->n_keys); 5822 seq_printf(m, " n_fields: %u\n", hist_data->n_fields); 5823 5824 seq_puts(m, "\n val fields:\n\n"); 5825 5826 seq_puts(m, " hist_data->fields[0]:\n"); 5827 ret = hist_field_debug_show(m, hist_data->fields[0], 5828 HIST_FIELD_FL_HITCOUNT); 5829 if (ret) 5830 return; 5831 5832 for (i = 1; i < hist_data->n_vals; i++) { 5833 seq_printf(m, "\n hist_data->fields[%d]:\n", i); 5834 ret = hist_field_debug_show(m, hist_data->fields[i], 0); 5835 if (ret) 5836 return; 5837 } 5838 5839 seq_puts(m, "\n key fields:\n"); 5840 5841 for (i = hist_data->n_vals; i < hist_data->n_fields; i++) { 5842 seq_printf(m, "\n hist_data->fields[%d]:\n", i); 5843 ret = hist_field_debug_show(m, hist_data->fields[i], 5844 HIST_FIELD_FL_KEY); 5845 if (ret) 5846 return; 5847 } 5848 5849 if (hist_data->n_var_refs) 5850 seq_puts(m, "\n variable reference fields:\n"); 5851 5852 for (i = 0; i < hist_data->n_var_refs; i++) { 5853 seq_printf(m, "\n hist_data->var_refs[%d]:\n", i); 5854 ret = hist_field_debug_show(m, hist_data->var_refs[i], 5855 HIST_FIELD_FL_VAR_REF); 5856 if (ret) 5857 return; 5858 } 5859 5860 if (hist_data->n_field_vars) 5861 seq_puts(m, "\n field variables:\n"); 5862 5863 for (i = 0; i < hist_data->n_field_vars; i++) { 5864 ret = field_var_debug_show(m, hist_data->field_vars[i], i, false); 5865 if (ret) 5866 return; 5867 } 5868 5869 ret = hist_actions_debug_show(m, hist_data); 5870 if (ret) 5871 return; 5872 } 5873 5874 static int hist_debug_show(struct seq_file *m, void *v) 5875 { 5876 struct event_trigger_data *data; 5877 struct trace_event_file *event_file; 5878 int n = 0, ret = 0; 5879 5880 mutex_lock(&event_mutex); 5881 5882 event_file = event_file_data(m->private); 5883 if (unlikely(!event_file)) { 5884 ret = -ENODEV; 5885 goto out_unlock; 5886 } 5887 5888 list_for_each_entry(data, &event_file->triggers, list) { 5889 if (data->cmd_ops->trigger_type == ETT_EVENT_HIST) 5890 hist_trigger_debug_show(m, data, n++); 5891 } 5892 5893 out_unlock: 5894 mutex_unlock(&event_mutex); 5895 5896 return ret; 5897 } 5898 5899 static int event_hist_debug_open(struct inode *inode, struct file *file) 5900 { 5901 int ret; 5902 5903 ret = security_locked_down(LOCKDOWN_TRACEFS); 5904 if (ret) 5905 return ret; 5906 5907 return single_open(file, hist_debug_show, file); 5908 } 5909 5910 const struct file_operations event_hist_debug_fops = { 5911 .open = event_hist_debug_open, 5912 .read = seq_read, 5913 .llseek = seq_lseek, 5914 .release = single_release, 5915 }; 5916 #endif 5917 5918 static void hist_field_print(struct seq_file *m, struct hist_field *hist_field) 5919 { 5920 const char *field_name = hist_field_name(hist_field, 0); 5921 5922 if (hist_field->var.name) 5923 seq_printf(m, "%s=", hist_field->var.name); 5924 5925 if (hist_field->flags & HIST_FIELD_FL_CPU) 5926 seq_puts(m, "common_cpu"); 5927 else if (hist_field->flags & HIST_FIELD_FL_CONST) 5928 seq_printf(m, "%llu", hist_field->constant); 5929 else if (field_name) { 5930 if (hist_field->flags & HIST_FIELD_FL_VAR_REF || 5931 hist_field->flags & HIST_FIELD_FL_ALIAS) 5932 seq_putc(m, '$'); 5933 seq_printf(m, "%s", field_name); 5934 } else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP) 5935 seq_puts(m, "common_timestamp"); 5936 5937 if (hist_field->flags) { 5938 if (!(hist_field->flags & HIST_FIELD_FL_VAR_REF) && 5939 !(hist_field->flags & HIST_FIELD_FL_EXPR) && 5940 !(hist_field->flags & HIST_FIELD_FL_STACKTRACE)) { 5941 const char *flags = get_hist_field_flags(hist_field); 5942 5943 if (flags) 5944 seq_printf(m, ".%s", flags); 5945 } 5946 } 5947 if (hist_field->buckets) 5948 seq_printf(m, "=%ld", hist_field->buckets); 5949 } 5950 5951 static int event_hist_trigger_print(struct seq_file *m, 5952 struct event_trigger_data *data) 5953 { 5954 struct hist_trigger_data *hist_data = data->private_data; 5955 struct hist_field *field; 5956 bool have_var = false; 5957 bool show_val = false; 5958 unsigned int i; 5959 5960 seq_puts(m, HIST_PREFIX); 5961 5962 if (data->name) 5963 seq_printf(m, "%s:", data->name); 5964 5965 seq_puts(m, "keys="); 5966 5967 for_each_hist_key_field(i, hist_data) { 5968 field = hist_data->fields[i]; 5969 5970 if (i > hist_data->n_vals) 5971 seq_puts(m, ","); 5972 5973 if (field->flags & HIST_FIELD_FL_STACKTRACE) { 5974 if (field->field) 5975 seq_printf(m, "%s.stacktrace", field->field->name); 5976 else 5977 seq_puts(m, "common_stacktrace"); 5978 } else 5979 hist_field_print(m, field); 5980 } 5981 5982 seq_puts(m, ":vals="); 5983 5984 for_each_hist_val_field(i, hist_data) { 5985 field = hist_data->fields[i]; 5986 if (field->flags & HIST_FIELD_FL_VAR) { 5987 have_var = true; 5988 continue; 5989 } 5990 5991 if (i == HITCOUNT_IDX) { 5992 if (hist_data->attrs->no_hitcount) 5993 continue; 5994 seq_puts(m, "hitcount"); 5995 } else { 5996 if (show_val) 5997 seq_puts(m, ","); 5998 hist_field_print(m, field); 5999 } 6000 show_val = true; 6001 } 6002 6003 if (have_var) { 6004 unsigned int n = 0; 6005 6006 seq_puts(m, ":"); 6007 6008 for_each_hist_val_field(i, hist_data) { 6009 field = hist_data->fields[i]; 6010 6011 if (field->flags & HIST_FIELD_FL_VAR) { 6012 if (n++) 6013 seq_puts(m, ","); 6014 hist_field_print(m, field); 6015 } 6016 } 6017 } 6018 6019 seq_puts(m, ":sort="); 6020 6021 for (i = 0; i < hist_data->n_sort_keys; i++) { 6022 struct tracing_map_sort_key *sort_key; 6023 unsigned int idx, first_key_idx; 6024 6025 /* skip VAR vals */ 6026 first_key_idx = hist_data->n_vals - hist_data->n_vars; 6027 6028 sort_key = &hist_data->sort_keys[i]; 6029 idx = sort_key->field_idx; 6030 6031 if (WARN_ON(idx >= HIST_FIELDS_MAX)) 6032 return -EINVAL; 6033 6034 if (i > 0) 6035 seq_puts(m, ","); 6036 6037 if (idx == HITCOUNT_IDX) 6038 seq_puts(m, "hitcount"); 6039 else { 6040 if (idx >= first_key_idx) 6041 idx += hist_data->n_vars; 6042 hist_field_print(m, hist_data->fields[idx]); 6043 } 6044 6045 if (sort_key->descending) 6046 seq_puts(m, ".descending"); 6047 } 6048 seq_printf(m, ":size=%u", (1 << hist_data->map->map_bits)); 6049 if (hist_data->enable_timestamps) 6050 seq_printf(m, ":clock=%s", hist_data->attrs->clock); 6051 if (hist_data->attrs->no_hitcount) 6052 seq_puts(m, ":nohitcount"); 6053 6054 print_actions_spec(m, hist_data); 6055 6056 if (data->filter_str) 6057 seq_printf(m, " if %s", data->filter_str); 6058 6059 if (data->paused) 6060 seq_puts(m, " [paused]"); 6061 else 6062 seq_puts(m, " [active]"); 6063 6064 seq_putc(m, '\n'); 6065 6066 return 0; 6067 } 6068 6069 static int event_hist_trigger_init(struct event_trigger_data *data) 6070 { 6071 struct hist_trigger_data *hist_data = data->private_data; 6072 6073 if (!data->ref && hist_data->attrs->name) 6074 save_named_trigger(hist_data->attrs->name, data); 6075 6076 data->ref++; 6077 6078 return 0; 6079 } 6080 6081 static void unregister_field_var_hists(struct hist_trigger_data *hist_data) 6082 { 6083 struct trace_event_file *file; 6084 unsigned int i; 6085 char *cmd; 6086 int ret; 6087 6088 for (i = 0; i < hist_data->n_field_var_hists; i++) { 6089 file = hist_data->field_var_hists[i]->hist_data->event_file; 6090 cmd = hist_data->field_var_hists[i]->cmd; 6091 ret = event_hist_trigger_parse(&trigger_hist_cmd, file, 6092 "!hist", "hist", cmd); 6093 WARN_ON_ONCE(ret < 0); 6094 } 6095 } 6096 6097 static void event_hist_trigger_free(struct event_trigger_data *data) 6098 { 6099 struct hist_trigger_data *hist_data = data->private_data; 6100 6101 if (WARN_ON_ONCE(data->ref <= 0)) 6102 return; 6103 6104 data->ref--; 6105 if (!data->ref) { 6106 if (data->name) 6107 del_named_trigger(data); 6108 6109 trigger_data_free(data); 6110 6111 remove_hist_vars(hist_data); 6112 6113 unregister_field_var_hists(hist_data); 6114 6115 destroy_hist_data(hist_data); 6116 } 6117 } 6118 6119 static struct event_trigger_ops event_hist_trigger_ops = { 6120 .trigger = event_hist_trigger, 6121 .print = event_hist_trigger_print, 6122 .init = event_hist_trigger_init, 6123 .free = event_hist_trigger_free, 6124 }; 6125 6126 static int event_hist_trigger_named_init(struct event_trigger_data *data) 6127 { 6128 data->ref++; 6129 6130 save_named_trigger(data->named_data->name, data); 6131 6132 event_hist_trigger_init(data->named_data); 6133 6134 return 0; 6135 } 6136 6137 static void event_hist_trigger_named_free(struct event_trigger_data *data) 6138 { 6139 if (WARN_ON_ONCE(data->ref <= 0)) 6140 return; 6141 6142 event_hist_trigger_free(data->named_data); 6143 6144 data->ref--; 6145 if (!data->ref) { 6146 del_named_trigger(data); 6147 trigger_data_free(data); 6148 } 6149 } 6150 6151 static struct event_trigger_ops event_hist_trigger_named_ops = { 6152 .trigger = event_hist_trigger, 6153 .print = event_hist_trigger_print, 6154 .init = event_hist_trigger_named_init, 6155 .free = event_hist_trigger_named_free, 6156 }; 6157 6158 static struct event_trigger_ops *event_hist_get_trigger_ops(char *cmd, 6159 char *param) 6160 { 6161 return &event_hist_trigger_ops; 6162 } 6163 6164 static void hist_clear(struct event_trigger_data *data) 6165 { 6166 struct hist_trigger_data *hist_data = data->private_data; 6167 6168 if (data->name) 6169 pause_named_trigger(data); 6170 6171 tracepoint_synchronize_unregister(); 6172 6173 tracing_map_clear(hist_data->map); 6174 6175 if (data->name) 6176 unpause_named_trigger(data); 6177 } 6178 6179 static bool compatible_field(struct ftrace_event_field *field, 6180 struct ftrace_event_field *test_field) 6181 { 6182 if (field == test_field) 6183 return true; 6184 if (field == NULL || test_field == NULL) 6185 return false; 6186 if (strcmp(field->name, test_field->name) != 0) 6187 return false; 6188 if (strcmp(field->type, test_field->type) != 0) 6189 return false; 6190 if (field->size != test_field->size) 6191 return false; 6192 if (field->is_signed != test_field->is_signed) 6193 return false; 6194 6195 return true; 6196 } 6197 6198 static bool hist_trigger_match(struct event_trigger_data *data, 6199 struct event_trigger_data *data_test, 6200 struct event_trigger_data *named_data, 6201 bool ignore_filter) 6202 { 6203 struct tracing_map_sort_key *sort_key, *sort_key_test; 6204 struct hist_trigger_data *hist_data, *hist_data_test; 6205 struct hist_field *key_field, *key_field_test; 6206 unsigned int i; 6207 6208 if (named_data && (named_data != data_test) && 6209 (named_data != data_test->named_data)) 6210 return false; 6211 6212 if (!named_data && is_named_trigger(data_test)) 6213 return false; 6214 6215 hist_data = data->private_data; 6216 hist_data_test = data_test->private_data; 6217 6218 if (hist_data->n_vals != hist_data_test->n_vals || 6219 hist_data->n_fields != hist_data_test->n_fields || 6220 hist_data->n_sort_keys != hist_data_test->n_sort_keys) 6221 return false; 6222 6223 if (!ignore_filter) { 6224 if ((data->filter_str && !data_test->filter_str) || 6225 (!data->filter_str && data_test->filter_str)) 6226 return false; 6227 } 6228 6229 for_each_hist_field(i, hist_data) { 6230 key_field = hist_data->fields[i]; 6231 key_field_test = hist_data_test->fields[i]; 6232 6233 if (key_field->flags != key_field_test->flags) 6234 return false; 6235 if (!compatible_field(key_field->field, key_field_test->field)) 6236 return false; 6237 if (key_field->offset != key_field_test->offset) 6238 return false; 6239 if (key_field->size != key_field_test->size) 6240 return false; 6241 if (key_field->is_signed != key_field_test->is_signed) 6242 return false; 6243 if (!!key_field->var.name != !!key_field_test->var.name) 6244 return false; 6245 if (key_field->var.name && 6246 strcmp(key_field->var.name, key_field_test->var.name) != 0) 6247 return false; 6248 } 6249 6250 for (i = 0; i < hist_data->n_sort_keys; i++) { 6251 sort_key = &hist_data->sort_keys[i]; 6252 sort_key_test = &hist_data_test->sort_keys[i]; 6253 6254 if (sort_key->field_idx != sort_key_test->field_idx || 6255 sort_key->descending != sort_key_test->descending) 6256 return false; 6257 } 6258 6259 if (!ignore_filter && data->filter_str && 6260 (strcmp(data->filter_str, data_test->filter_str) != 0)) 6261 return false; 6262 6263 if (!actions_match(hist_data, hist_data_test)) 6264 return false; 6265 6266 return true; 6267 } 6268 6269 static bool existing_hist_update_only(char *glob, 6270 struct event_trigger_data *data, 6271 struct trace_event_file *file) 6272 { 6273 struct hist_trigger_data *hist_data = data->private_data; 6274 struct event_trigger_data *test, *named_data = NULL; 6275 bool updated = false; 6276 6277 if (!hist_data->attrs->pause && !hist_data->attrs->cont && 6278 !hist_data->attrs->clear) 6279 goto out; 6280 6281 if (hist_data->attrs->name) { 6282 named_data = find_named_trigger(hist_data->attrs->name); 6283 if (named_data) { 6284 if (!hist_trigger_match(data, named_data, named_data, 6285 true)) 6286 goto out; 6287 } 6288 } 6289 6290 if (hist_data->attrs->name && !named_data) 6291 goto out; 6292 6293 list_for_each_entry(test, &file->triggers, list) { 6294 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6295 if (!hist_trigger_match(data, test, named_data, false)) 6296 continue; 6297 if (hist_data->attrs->pause) 6298 test->paused = true; 6299 else if (hist_data->attrs->cont) 6300 test->paused = false; 6301 else if (hist_data->attrs->clear) 6302 hist_clear(test); 6303 updated = true; 6304 goto out; 6305 } 6306 } 6307 out: 6308 return updated; 6309 } 6310 6311 static int hist_register_trigger(char *glob, 6312 struct event_trigger_data *data, 6313 struct trace_event_file *file) 6314 { 6315 struct hist_trigger_data *hist_data = data->private_data; 6316 struct event_trigger_data *test, *named_data = NULL; 6317 struct trace_array *tr = file->tr; 6318 int ret = 0; 6319 6320 if (hist_data->attrs->name) { 6321 named_data = find_named_trigger(hist_data->attrs->name); 6322 if (named_data) { 6323 if (!hist_trigger_match(data, named_data, named_data, 6324 true)) { 6325 hist_err(tr, HIST_ERR_NAMED_MISMATCH, errpos(hist_data->attrs->name)); 6326 ret = -EINVAL; 6327 goto out; 6328 } 6329 } 6330 } 6331 6332 if (hist_data->attrs->name && !named_data) 6333 goto new; 6334 6335 lockdep_assert_held(&event_mutex); 6336 6337 list_for_each_entry(test, &file->triggers, list) { 6338 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6339 if (hist_trigger_match(data, test, named_data, false)) { 6340 hist_err(tr, HIST_ERR_TRIGGER_EEXIST, 0); 6341 ret = -EEXIST; 6342 goto out; 6343 } 6344 } 6345 } 6346 new: 6347 if (hist_data->attrs->cont || hist_data->attrs->clear) { 6348 hist_err(tr, HIST_ERR_TRIGGER_ENOENT_CLEAR, 0); 6349 ret = -ENOENT; 6350 goto out; 6351 } 6352 6353 if (hist_data->attrs->pause) 6354 data->paused = true; 6355 6356 if (named_data) { 6357 data->private_data = named_data->private_data; 6358 set_named_trigger_data(data, named_data); 6359 data->ops = &event_hist_trigger_named_ops; 6360 } 6361 6362 if (data->ops->init) { 6363 ret = data->ops->init(data); 6364 if (ret < 0) 6365 goto out; 6366 } 6367 6368 if (hist_data->enable_timestamps) { 6369 char *clock = hist_data->attrs->clock; 6370 6371 ret = tracing_set_clock(file->tr, hist_data->attrs->clock); 6372 if (ret) { 6373 hist_err(tr, HIST_ERR_SET_CLOCK_FAIL, errpos(clock)); 6374 goto out; 6375 } 6376 6377 tracing_set_filter_buffering(file->tr, true); 6378 } 6379 6380 if (named_data) 6381 destroy_hist_data(hist_data); 6382 out: 6383 return ret; 6384 } 6385 6386 static int hist_trigger_enable(struct event_trigger_data *data, 6387 struct trace_event_file *file) 6388 { 6389 int ret = 0; 6390 6391 list_add_tail_rcu(&data->list, &file->triggers); 6392 6393 update_cond_flag(file); 6394 6395 if (trace_event_trigger_enable_disable(file, 1) < 0) { 6396 list_del_rcu(&data->list); 6397 update_cond_flag(file); 6398 ret--; 6399 } 6400 6401 return ret; 6402 } 6403 6404 static bool have_hist_trigger_match(struct event_trigger_data *data, 6405 struct trace_event_file *file) 6406 { 6407 struct hist_trigger_data *hist_data = data->private_data; 6408 struct event_trigger_data *test, *named_data = NULL; 6409 bool match = false; 6410 6411 lockdep_assert_held(&event_mutex); 6412 6413 if (hist_data->attrs->name) 6414 named_data = find_named_trigger(hist_data->attrs->name); 6415 6416 list_for_each_entry(test, &file->triggers, list) { 6417 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6418 if (hist_trigger_match(data, test, named_data, false)) { 6419 match = true; 6420 break; 6421 } 6422 } 6423 } 6424 6425 return match; 6426 } 6427 6428 static bool hist_trigger_check_refs(struct event_trigger_data *data, 6429 struct trace_event_file *file) 6430 { 6431 struct hist_trigger_data *hist_data = data->private_data; 6432 struct event_trigger_data *test, *named_data = NULL; 6433 6434 lockdep_assert_held(&event_mutex); 6435 6436 if (hist_data->attrs->name) 6437 named_data = find_named_trigger(hist_data->attrs->name); 6438 6439 list_for_each_entry(test, &file->triggers, list) { 6440 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6441 if (!hist_trigger_match(data, test, named_data, false)) 6442 continue; 6443 hist_data = test->private_data; 6444 if (check_var_refs(hist_data)) 6445 return true; 6446 break; 6447 } 6448 } 6449 6450 return false; 6451 } 6452 6453 static void hist_unregister_trigger(char *glob, 6454 struct event_trigger_data *data, 6455 struct trace_event_file *file) 6456 { 6457 struct event_trigger_data *test = NULL, *iter, *named_data = NULL; 6458 struct hist_trigger_data *hist_data = data->private_data; 6459 6460 lockdep_assert_held(&event_mutex); 6461 6462 if (hist_data->attrs->name) 6463 named_data = find_named_trigger(hist_data->attrs->name); 6464 6465 list_for_each_entry(iter, &file->triggers, list) { 6466 if (iter->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6467 if (!hist_trigger_match(data, iter, named_data, false)) 6468 continue; 6469 test = iter; 6470 list_del_rcu(&test->list); 6471 trace_event_trigger_enable_disable(file, 0); 6472 update_cond_flag(file); 6473 break; 6474 } 6475 } 6476 6477 if (test && test->ops->free) 6478 test->ops->free(test); 6479 6480 if (hist_data->enable_timestamps) { 6481 if (!hist_data->remove || test) 6482 tracing_set_filter_buffering(file->tr, false); 6483 } 6484 } 6485 6486 static bool hist_file_check_refs(struct trace_event_file *file) 6487 { 6488 struct hist_trigger_data *hist_data; 6489 struct event_trigger_data *test; 6490 6491 lockdep_assert_held(&event_mutex); 6492 6493 list_for_each_entry(test, &file->triggers, list) { 6494 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6495 hist_data = test->private_data; 6496 if (check_var_refs(hist_data)) 6497 return true; 6498 } 6499 } 6500 6501 return false; 6502 } 6503 6504 static void hist_unreg_all(struct trace_event_file *file) 6505 { 6506 struct event_trigger_data *test, *n; 6507 struct hist_trigger_data *hist_data; 6508 struct synth_event *se; 6509 const char *se_name; 6510 6511 lockdep_assert_held(&event_mutex); 6512 6513 if (hist_file_check_refs(file)) 6514 return; 6515 6516 list_for_each_entry_safe(test, n, &file->triggers, list) { 6517 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6518 hist_data = test->private_data; 6519 list_del_rcu(&test->list); 6520 trace_event_trigger_enable_disable(file, 0); 6521 6522 se_name = trace_event_name(file->event_call); 6523 se = find_synth_event(se_name); 6524 if (se) 6525 se->ref--; 6526 6527 update_cond_flag(file); 6528 if (hist_data->enable_timestamps) 6529 tracing_set_filter_buffering(file->tr, false); 6530 if (test->ops->free) 6531 test->ops->free(test); 6532 } 6533 } 6534 } 6535 6536 static int event_hist_trigger_parse(struct event_command *cmd_ops, 6537 struct trace_event_file *file, 6538 char *glob, char *cmd, 6539 char *param_and_filter) 6540 { 6541 unsigned int hist_trigger_bits = TRACING_MAP_BITS_DEFAULT; 6542 struct event_trigger_data *trigger_data; 6543 struct hist_trigger_attrs *attrs; 6544 struct hist_trigger_data *hist_data; 6545 char *param, *filter, *p, *start; 6546 struct synth_event *se; 6547 const char *se_name; 6548 bool remove; 6549 int ret = 0; 6550 6551 lockdep_assert_held(&event_mutex); 6552 6553 if (WARN_ON(!glob)) 6554 return -EINVAL; 6555 6556 if (glob[0]) { 6557 hist_err_clear(); 6558 last_cmd_set(file, param_and_filter); 6559 } 6560 6561 remove = event_trigger_check_remove(glob); 6562 6563 if (event_trigger_empty_param(param_and_filter)) 6564 return -EINVAL; 6565 6566 /* 6567 * separate the trigger from the filter (k:v [if filter]) 6568 * allowing for whitespace in the trigger 6569 */ 6570 p = param = param_and_filter; 6571 do { 6572 p = strstr(p, "if"); 6573 if (!p) 6574 break; 6575 if (p == param_and_filter) 6576 return -EINVAL; 6577 if (*(p - 1) != ' ' && *(p - 1) != '\t') { 6578 p++; 6579 continue; 6580 } 6581 if (p >= param_and_filter + strlen(param_and_filter) - (sizeof("if") - 1) - 1) 6582 return -EINVAL; 6583 if (*(p + sizeof("if") - 1) != ' ' && *(p + sizeof("if") - 1) != '\t') { 6584 p++; 6585 continue; 6586 } 6587 break; 6588 } while (1); 6589 6590 if (!p) 6591 filter = NULL; 6592 else { 6593 *(p - 1) = '\0'; 6594 filter = strstrip(p); 6595 param = strstrip(param); 6596 } 6597 6598 /* 6599 * To simplify arithmetic expression parsing, replace occurrences of 6600 * '.sym-offset' modifier with '.symXoffset' 6601 */ 6602 start = strstr(param, ".sym-offset"); 6603 while (start) { 6604 *(start + 4) = 'X'; 6605 start = strstr(start + 11, ".sym-offset"); 6606 } 6607 6608 attrs = parse_hist_trigger_attrs(file->tr, param); 6609 if (IS_ERR(attrs)) 6610 return PTR_ERR(attrs); 6611 6612 if (attrs->map_bits) 6613 hist_trigger_bits = attrs->map_bits; 6614 6615 hist_data = create_hist_data(hist_trigger_bits, attrs, file, remove); 6616 if (IS_ERR(hist_data)) { 6617 destroy_hist_trigger_attrs(attrs); 6618 return PTR_ERR(hist_data); 6619 } 6620 6621 trigger_data = event_trigger_alloc(cmd_ops, cmd, param, hist_data); 6622 if (!trigger_data) { 6623 ret = -ENOMEM; 6624 goto out_free; 6625 } 6626 6627 ret = event_trigger_set_filter(cmd_ops, file, filter, trigger_data); 6628 if (ret < 0) 6629 goto out_free; 6630 6631 if (remove) { 6632 if (!have_hist_trigger_match(trigger_data, file)) 6633 goto out_free; 6634 6635 if (hist_trigger_check_refs(trigger_data, file)) { 6636 ret = -EBUSY; 6637 goto out_free; 6638 } 6639 6640 event_trigger_unregister(cmd_ops, file, glob+1, trigger_data); 6641 se_name = trace_event_name(file->event_call); 6642 se = find_synth_event(se_name); 6643 if (se) 6644 se->ref--; 6645 ret = 0; 6646 goto out_free; 6647 } 6648 6649 if (existing_hist_update_only(glob, trigger_data, file)) 6650 goto out_free; 6651 6652 ret = event_trigger_register(cmd_ops, file, glob, trigger_data); 6653 if (ret < 0) 6654 goto out_free; 6655 6656 if (get_named_trigger_data(trigger_data)) 6657 goto enable; 6658 6659 ret = create_actions(hist_data); 6660 if (ret) 6661 goto out_unreg; 6662 6663 if (has_hist_vars(hist_data) || hist_data->n_var_refs) { 6664 ret = save_hist_vars(hist_data); 6665 if (ret) 6666 goto out_unreg; 6667 } 6668 6669 ret = tracing_map_init(hist_data->map); 6670 if (ret) 6671 goto out_unreg; 6672 enable: 6673 ret = hist_trigger_enable(trigger_data, file); 6674 if (ret) 6675 goto out_unreg; 6676 6677 se_name = trace_event_name(file->event_call); 6678 se = find_synth_event(se_name); 6679 if (se) 6680 se->ref++; 6681 out: 6682 if (ret == 0 && glob[0]) 6683 hist_err_clear(); 6684 6685 return ret; 6686 out_unreg: 6687 event_trigger_unregister(cmd_ops, file, glob+1, trigger_data); 6688 out_free: 6689 event_trigger_reset_filter(cmd_ops, trigger_data); 6690 6691 remove_hist_vars(hist_data); 6692 6693 kfree(trigger_data); 6694 6695 destroy_hist_data(hist_data); 6696 goto out; 6697 } 6698 6699 static struct event_command trigger_hist_cmd = { 6700 .name = "hist", 6701 .trigger_type = ETT_EVENT_HIST, 6702 .flags = EVENT_CMD_FL_NEEDS_REC, 6703 .parse = event_hist_trigger_parse, 6704 .reg = hist_register_trigger, 6705 .unreg = hist_unregister_trigger, 6706 .unreg_all = hist_unreg_all, 6707 .get_trigger_ops = event_hist_get_trigger_ops, 6708 .set_filter = set_trigger_filter, 6709 }; 6710 6711 __init int register_trigger_hist_cmd(void) 6712 { 6713 int ret; 6714 6715 ret = register_event_command(&trigger_hist_cmd); 6716 WARN_ON(ret < 0); 6717 6718 return ret; 6719 } 6720 6721 static void 6722 hist_enable_trigger(struct event_trigger_data *data, 6723 struct trace_buffer *buffer, void *rec, 6724 struct ring_buffer_event *event) 6725 { 6726 struct enable_trigger_data *enable_data = data->private_data; 6727 struct event_trigger_data *test; 6728 6729 list_for_each_entry_rcu(test, &enable_data->file->triggers, list, 6730 lockdep_is_held(&event_mutex)) { 6731 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6732 if (enable_data->enable) 6733 test->paused = false; 6734 else 6735 test->paused = true; 6736 } 6737 } 6738 } 6739 6740 static void 6741 hist_enable_count_trigger(struct event_trigger_data *data, 6742 struct trace_buffer *buffer, void *rec, 6743 struct ring_buffer_event *event) 6744 { 6745 if (!data->count) 6746 return; 6747 6748 if (data->count != -1) 6749 (data->count)--; 6750 6751 hist_enable_trigger(data, buffer, rec, event); 6752 } 6753 6754 static struct event_trigger_ops hist_enable_trigger_ops = { 6755 .trigger = hist_enable_trigger, 6756 .print = event_enable_trigger_print, 6757 .init = event_trigger_init, 6758 .free = event_enable_trigger_free, 6759 }; 6760 6761 static struct event_trigger_ops hist_enable_count_trigger_ops = { 6762 .trigger = hist_enable_count_trigger, 6763 .print = event_enable_trigger_print, 6764 .init = event_trigger_init, 6765 .free = event_enable_trigger_free, 6766 }; 6767 6768 static struct event_trigger_ops hist_disable_trigger_ops = { 6769 .trigger = hist_enable_trigger, 6770 .print = event_enable_trigger_print, 6771 .init = event_trigger_init, 6772 .free = event_enable_trigger_free, 6773 }; 6774 6775 static struct event_trigger_ops hist_disable_count_trigger_ops = { 6776 .trigger = hist_enable_count_trigger, 6777 .print = event_enable_trigger_print, 6778 .init = event_trigger_init, 6779 .free = event_enable_trigger_free, 6780 }; 6781 6782 static struct event_trigger_ops * 6783 hist_enable_get_trigger_ops(char *cmd, char *param) 6784 { 6785 struct event_trigger_ops *ops; 6786 bool enable; 6787 6788 enable = (strcmp(cmd, ENABLE_HIST_STR) == 0); 6789 6790 if (enable) 6791 ops = param ? &hist_enable_count_trigger_ops : 6792 &hist_enable_trigger_ops; 6793 else 6794 ops = param ? &hist_disable_count_trigger_ops : 6795 &hist_disable_trigger_ops; 6796 6797 return ops; 6798 } 6799 6800 static void hist_enable_unreg_all(struct trace_event_file *file) 6801 { 6802 struct event_trigger_data *test, *n; 6803 6804 list_for_each_entry_safe(test, n, &file->triggers, list) { 6805 if (test->cmd_ops->trigger_type == ETT_HIST_ENABLE) { 6806 list_del_rcu(&test->list); 6807 update_cond_flag(file); 6808 trace_event_trigger_enable_disable(file, 0); 6809 if (test->ops->free) 6810 test->ops->free(test); 6811 } 6812 } 6813 } 6814 6815 static struct event_command trigger_hist_enable_cmd = { 6816 .name = ENABLE_HIST_STR, 6817 .trigger_type = ETT_HIST_ENABLE, 6818 .parse = event_enable_trigger_parse, 6819 .reg = event_enable_register_trigger, 6820 .unreg = event_enable_unregister_trigger, 6821 .unreg_all = hist_enable_unreg_all, 6822 .get_trigger_ops = hist_enable_get_trigger_ops, 6823 .set_filter = set_trigger_filter, 6824 }; 6825 6826 static struct event_command trigger_hist_disable_cmd = { 6827 .name = DISABLE_HIST_STR, 6828 .trigger_type = ETT_HIST_ENABLE, 6829 .parse = event_enable_trigger_parse, 6830 .reg = event_enable_register_trigger, 6831 .unreg = event_enable_unregister_trigger, 6832 .unreg_all = hist_enable_unreg_all, 6833 .get_trigger_ops = hist_enable_get_trigger_ops, 6834 .set_filter = set_trigger_filter, 6835 }; 6836 6837 static __init void unregister_trigger_hist_enable_disable_cmds(void) 6838 { 6839 unregister_event_command(&trigger_hist_enable_cmd); 6840 unregister_event_command(&trigger_hist_disable_cmd); 6841 } 6842 6843 __init int register_trigger_hist_enable_disable_cmds(void) 6844 { 6845 int ret; 6846 6847 ret = register_event_command(&trigger_hist_enable_cmd); 6848 if (WARN_ON(ret < 0)) 6849 return ret; 6850 ret = register_event_command(&trigger_hist_disable_cmd); 6851 if (WARN_ON(ret < 0)) 6852 unregister_trigger_hist_enable_disable_cmds(); 6853 6854 return ret; 6855 } 6856