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(static_key_enabled(&tp->key))) { 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 field_name = "common_stacktrace"; 1358 } else if (field->flags & HIST_FIELD_FL_HITCOUNT) 1359 field_name = "hitcount"; 1360 1361 if (field_name == NULL) 1362 field_name = ""; 1363 1364 return field_name; 1365 } 1366 1367 static enum hist_field_fn select_value_fn(int field_size, int field_is_signed) 1368 { 1369 switch (field_size) { 1370 case 8: 1371 if (field_is_signed) 1372 return HIST_FIELD_FN_S64; 1373 else 1374 return HIST_FIELD_FN_U64; 1375 case 4: 1376 if (field_is_signed) 1377 return HIST_FIELD_FN_S32; 1378 else 1379 return HIST_FIELD_FN_U32; 1380 case 2: 1381 if (field_is_signed) 1382 return HIST_FIELD_FN_S16; 1383 else 1384 return HIST_FIELD_FN_U16; 1385 case 1: 1386 if (field_is_signed) 1387 return HIST_FIELD_FN_S8; 1388 else 1389 return HIST_FIELD_FN_U8; 1390 } 1391 1392 return HIST_FIELD_FN_NOP; 1393 } 1394 1395 static int parse_map_size(char *str) 1396 { 1397 unsigned long size, map_bits; 1398 int ret; 1399 1400 ret = kstrtoul(str, 0, &size); 1401 if (ret) 1402 goto out; 1403 1404 map_bits = ilog2(roundup_pow_of_two(size)); 1405 if (map_bits < TRACING_MAP_BITS_MIN || 1406 map_bits > TRACING_MAP_BITS_MAX) 1407 ret = -EINVAL; 1408 else 1409 ret = map_bits; 1410 out: 1411 return ret; 1412 } 1413 1414 static void destroy_hist_trigger_attrs(struct hist_trigger_attrs *attrs) 1415 { 1416 unsigned int i; 1417 1418 if (!attrs) 1419 return; 1420 1421 for (i = 0; i < attrs->n_assignments; i++) 1422 kfree(attrs->assignment_str[i]); 1423 1424 for (i = 0; i < attrs->n_actions; i++) 1425 kfree(attrs->action_str[i]); 1426 1427 kfree(attrs->name); 1428 kfree(attrs->sort_key_str); 1429 kfree(attrs->keys_str); 1430 kfree(attrs->vals_str); 1431 kfree(attrs->clock); 1432 kfree(attrs); 1433 } 1434 1435 static int parse_action(char *str, struct hist_trigger_attrs *attrs) 1436 { 1437 int ret = -EINVAL; 1438 1439 if (attrs->n_actions >= HIST_ACTIONS_MAX) 1440 return ret; 1441 1442 if ((str_has_prefix(str, "onmatch(")) || 1443 (str_has_prefix(str, "onmax(")) || 1444 (str_has_prefix(str, "onchange("))) { 1445 attrs->action_str[attrs->n_actions] = kstrdup(str, GFP_KERNEL); 1446 if (!attrs->action_str[attrs->n_actions]) { 1447 ret = -ENOMEM; 1448 return ret; 1449 } 1450 attrs->n_actions++; 1451 ret = 0; 1452 } 1453 return ret; 1454 } 1455 1456 static int parse_assignment(struct trace_array *tr, 1457 char *str, struct hist_trigger_attrs *attrs) 1458 { 1459 int len, ret = 0; 1460 1461 if ((len = str_has_prefix(str, "key=")) || 1462 (len = str_has_prefix(str, "keys="))) { 1463 attrs->keys_str = kstrdup(str + len, GFP_KERNEL); 1464 if (!attrs->keys_str) { 1465 ret = -ENOMEM; 1466 goto out; 1467 } 1468 } else if ((len = str_has_prefix(str, "val=")) || 1469 (len = str_has_prefix(str, "vals=")) || 1470 (len = str_has_prefix(str, "values="))) { 1471 attrs->vals_str = kstrdup(str + len, GFP_KERNEL); 1472 if (!attrs->vals_str) { 1473 ret = -ENOMEM; 1474 goto out; 1475 } 1476 } else if ((len = str_has_prefix(str, "sort="))) { 1477 attrs->sort_key_str = kstrdup(str + len, GFP_KERNEL); 1478 if (!attrs->sort_key_str) { 1479 ret = -ENOMEM; 1480 goto out; 1481 } 1482 } else if (str_has_prefix(str, "name=")) { 1483 attrs->name = kstrdup(str, GFP_KERNEL); 1484 if (!attrs->name) { 1485 ret = -ENOMEM; 1486 goto out; 1487 } 1488 } else if ((len = str_has_prefix(str, "clock="))) { 1489 str += len; 1490 1491 str = strstrip(str); 1492 attrs->clock = kstrdup(str, GFP_KERNEL); 1493 if (!attrs->clock) { 1494 ret = -ENOMEM; 1495 goto out; 1496 } 1497 } else if ((len = str_has_prefix(str, "size="))) { 1498 int map_bits = parse_map_size(str + len); 1499 1500 if (map_bits < 0) { 1501 ret = map_bits; 1502 goto out; 1503 } 1504 attrs->map_bits = map_bits; 1505 } else { 1506 char *assignment; 1507 1508 if (attrs->n_assignments == TRACING_MAP_VARS_MAX) { 1509 hist_err(tr, HIST_ERR_TOO_MANY_VARS, errpos(str)); 1510 ret = -EINVAL; 1511 goto out; 1512 } 1513 1514 assignment = kstrdup(str, GFP_KERNEL); 1515 if (!assignment) { 1516 ret = -ENOMEM; 1517 goto out; 1518 } 1519 1520 attrs->assignment_str[attrs->n_assignments++] = assignment; 1521 } 1522 out: 1523 return ret; 1524 } 1525 1526 static struct hist_trigger_attrs * 1527 parse_hist_trigger_attrs(struct trace_array *tr, char *trigger_str) 1528 { 1529 struct hist_trigger_attrs *attrs; 1530 int ret = 0; 1531 1532 attrs = kzalloc(sizeof(*attrs), GFP_KERNEL); 1533 if (!attrs) 1534 return ERR_PTR(-ENOMEM); 1535 1536 while (trigger_str) { 1537 char *str = strsep(&trigger_str, ":"); 1538 char *rhs; 1539 1540 rhs = strchr(str, '='); 1541 if (rhs) { 1542 if (!strlen(++rhs)) { 1543 ret = -EINVAL; 1544 hist_err(tr, HIST_ERR_EMPTY_ASSIGNMENT, errpos(str)); 1545 goto free; 1546 } 1547 ret = parse_assignment(tr, str, attrs); 1548 if (ret) 1549 goto free; 1550 } else if (strcmp(str, "nohitcount") == 0 || 1551 strcmp(str, "NOHC") == 0) 1552 attrs->no_hitcount = true; 1553 else if (strcmp(str, "pause") == 0) 1554 attrs->pause = true; 1555 else if ((strcmp(str, "cont") == 0) || 1556 (strcmp(str, "continue") == 0)) 1557 attrs->cont = true; 1558 else if (strcmp(str, "clear") == 0) 1559 attrs->clear = true; 1560 else { 1561 ret = parse_action(str, attrs); 1562 if (ret) 1563 goto free; 1564 } 1565 } 1566 1567 if (!attrs->keys_str) { 1568 ret = -EINVAL; 1569 goto free; 1570 } 1571 1572 if (!attrs->clock) { 1573 attrs->clock = kstrdup("global", GFP_KERNEL); 1574 if (!attrs->clock) { 1575 ret = -ENOMEM; 1576 goto free; 1577 } 1578 } 1579 1580 return attrs; 1581 free: 1582 destroy_hist_trigger_attrs(attrs); 1583 1584 return ERR_PTR(ret); 1585 } 1586 1587 static inline void save_comm(char *comm, struct task_struct *task) 1588 { 1589 if (!task->pid) { 1590 strcpy(comm, "<idle>"); 1591 return; 1592 } 1593 1594 if (WARN_ON_ONCE(task->pid < 0)) { 1595 strcpy(comm, "<XXX>"); 1596 return; 1597 } 1598 1599 strscpy(comm, task->comm, TASK_COMM_LEN); 1600 } 1601 1602 static void hist_elt_data_free(struct hist_elt_data *elt_data) 1603 { 1604 unsigned int i; 1605 1606 for (i = 0; i < elt_data->n_field_var_str; i++) 1607 kfree(elt_data->field_var_str[i]); 1608 1609 kfree(elt_data->field_var_str); 1610 1611 kfree(elt_data->comm); 1612 kfree(elt_data); 1613 } 1614 1615 static void hist_trigger_elt_data_free(struct tracing_map_elt *elt) 1616 { 1617 struct hist_elt_data *elt_data = elt->private_data; 1618 1619 hist_elt_data_free(elt_data); 1620 } 1621 1622 static int hist_trigger_elt_data_alloc(struct tracing_map_elt *elt) 1623 { 1624 struct hist_trigger_data *hist_data = elt->map->private_data; 1625 unsigned int size = TASK_COMM_LEN; 1626 struct hist_elt_data *elt_data; 1627 struct hist_field *hist_field; 1628 unsigned int i, n_str; 1629 1630 elt_data = kzalloc(sizeof(*elt_data), GFP_KERNEL); 1631 if (!elt_data) 1632 return -ENOMEM; 1633 1634 for_each_hist_field(i, hist_data) { 1635 hist_field = hist_data->fields[i]; 1636 1637 if (hist_field->flags & HIST_FIELD_FL_EXECNAME) { 1638 elt_data->comm = kzalloc(size, GFP_KERNEL); 1639 if (!elt_data->comm) { 1640 kfree(elt_data); 1641 return -ENOMEM; 1642 } 1643 break; 1644 } 1645 } 1646 1647 n_str = hist_data->n_field_var_str + hist_data->n_save_var_str + 1648 hist_data->n_var_str; 1649 if (n_str > SYNTH_FIELDS_MAX) { 1650 hist_elt_data_free(elt_data); 1651 return -EINVAL; 1652 } 1653 1654 BUILD_BUG_ON(STR_VAR_LEN_MAX & (sizeof(u64) - 1)); 1655 1656 size = STR_VAR_LEN_MAX; 1657 1658 elt_data->field_var_str = kcalloc(n_str, sizeof(char *), GFP_KERNEL); 1659 if (!elt_data->field_var_str) { 1660 hist_elt_data_free(elt_data); 1661 return -EINVAL; 1662 } 1663 elt_data->n_field_var_str = n_str; 1664 1665 for (i = 0; i < n_str; i++) { 1666 elt_data->field_var_str[i] = kzalloc(size, GFP_KERNEL); 1667 if (!elt_data->field_var_str[i]) { 1668 hist_elt_data_free(elt_data); 1669 return -ENOMEM; 1670 } 1671 } 1672 1673 elt->private_data = elt_data; 1674 1675 return 0; 1676 } 1677 1678 static void hist_trigger_elt_data_init(struct tracing_map_elt *elt) 1679 { 1680 struct hist_elt_data *elt_data = elt->private_data; 1681 1682 if (elt_data->comm) 1683 save_comm(elt_data->comm, current); 1684 } 1685 1686 static const struct tracing_map_ops hist_trigger_elt_data_ops = { 1687 .elt_alloc = hist_trigger_elt_data_alloc, 1688 .elt_free = hist_trigger_elt_data_free, 1689 .elt_init = hist_trigger_elt_data_init, 1690 }; 1691 1692 static const char *get_hist_field_flags(struct hist_field *hist_field) 1693 { 1694 const char *flags_str = NULL; 1695 1696 if (hist_field->flags & HIST_FIELD_FL_HEX) 1697 flags_str = "hex"; 1698 else if (hist_field->flags & HIST_FIELD_FL_SYM) 1699 flags_str = "sym"; 1700 else if (hist_field->flags & HIST_FIELD_FL_SYM_OFFSET) 1701 flags_str = "sym-offset"; 1702 else if (hist_field->flags & HIST_FIELD_FL_EXECNAME) 1703 flags_str = "execname"; 1704 else if (hist_field->flags & HIST_FIELD_FL_SYSCALL) 1705 flags_str = "syscall"; 1706 else if (hist_field->flags & HIST_FIELD_FL_LOG2) 1707 flags_str = "log2"; 1708 else if (hist_field->flags & HIST_FIELD_FL_BUCKET) 1709 flags_str = "buckets"; 1710 else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP_USECS) 1711 flags_str = "usecs"; 1712 else if (hist_field->flags & HIST_FIELD_FL_PERCENT) 1713 flags_str = "percent"; 1714 else if (hist_field->flags & HIST_FIELD_FL_GRAPH) 1715 flags_str = "graph"; 1716 else if (hist_field->flags & HIST_FIELD_FL_STACKTRACE) 1717 flags_str = "stacktrace"; 1718 1719 return flags_str; 1720 } 1721 1722 static void expr_field_str(struct hist_field *field, char *expr) 1723 { 1724 if (field->flags & HIST_FIELD_FL_VAR_REF) 1725 strcat(expr, "$"); 1726 else if (field->flags & HIST_FIELD_FL_CONST) { 1727 char str[HIST_CONST_DIGITS_MAX]; 1728 1729 snprintf(str, HIST_CONST_DIGITS_MAX, "%llu", field->constant); 1730 strcat(expr, str); 1731 } 1732 1733 strcat(expr, hist_field_name(field, 0)); 1734 1735 if (field->flags && !(field->flags & HIST_FIELD_FL_VAR_REF)) { 1736 const char *flags_str = get_hist_field_flags(field); 1737 1738 if (flags_str) { 1739 strcat(expr, "."); 1740 strcat(expr, flags_str); 1741 } 1742 } 1743 } 1744 1745 static char *expr_str(struct hist_field *field, unsigned int level) 1746 { 1747 char *expr; 1748 1749 if (level > 1) 1750 return NULL; 1751 1752 expr = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL); 1753 if (!expr) 1754 return NULL; 1755 1756 if (!field->operands[0]) { 1757 expr_field_str(field, expr); 1758 return expr; 1759 } 1760 1761 if (field->operator == FIELD_OP_UNARY_MINUS) { 1762 char *subexpr; 1763 1764 strcat(expr, "-("); 1765 subexpr = expr_str(field->operands[0], ++level); 1766 if (!subexpr) { 1767 kfree(expr); 1768 return NULL; 1769 } 1770 strcat(expr, subexpr); 1771 strcat(expr, ")"); 1772 1773 kfree(subexpr); 1774 1775 return expr; 1776 } 1777 1778 expr_field_str(field->operands[0], expr); 1779 1780 switch (field->operator) { 1781 case FIELD_OP_MINUS: 1782 strcat(expr, "-"); 1783 break; 1784 case FIELD_OP_PLUS: 1785 strcat(expr, "+"); 1786 break; 1787 case FIELD_OP_DIV: 1788 strcat(expr, "/"); 1789 break; 1790 case FIELD_OP_MULT: 1791 strcat(expr, "*"); 1792 break; 1793 default: 1794 kfree(expr); 1795 return NULL; 1796 } 1797 1798 expr_field_str(field->operands[1], expr); 1799 1800 return expr; 1801 } 1802 1803 /* 1804 * If field_op != FIELD_OP_NONE, *sep points to the root operator 1805 * of the expression tree to be evaluated. 1806 */ 1807 static int contains_operator(char *str, char **sep) 1808 { 1809 enum field_op_id field_op = FIELD_OP_NONE; 1810 char *minus_op, *plus_op, *div_op, *mult_op; 1811 1812 1813 /* 1814 * Report the last occurrence of the operators first, so that the 1815 * expression is evaluated left to right. This is important since 1816 * subtraction and division are not associative. 1817 * 1818 * e.g 1819 * 64/8/4/2 is 1, i.e 64/8/4/2 = ((64/8)/4)/2 1820 * 14-7-5-2 is 0, i.e 14-7-5-2 = ((14-7)-5)-2 1821 */ 1822 1823 /* 1824 * First, find lower precedence addition and subtraction 1825 * since the expression will be evaluated recursively. 1826 */ 1827 minus_op = strrchr(str, '-'); 1828 if (minus_op) { 1829 /* 1830 * Unary minus is not supported in sub-expressions. If 1831 * present, it is always the next root operator. 1832 */ 1833 if (minus_op == str) { 1834 field_op = FIELD_OP_UNARY_MINUS; 1835 goto out; 1836 } 1837 1838 field_op = FIELD_OP_MINUS; 1839 } 1840 1841 plus_op = strrchr(str, '+'); 1842 if (plus_op || minus_op) { 1843 /* 1844 * For operators of the same precedence use to rightmost as the 1845 * root, so that the expression is evaluated left to right. 1846 */ 1847 if (plus_op > minus_op) 1848 field_op = FIELD_OP_PLUS; 1849 goto out; 1850 } 1851 1852 /* 1853 * Multiplication and division have higher precedence than addition and 1854 * subtraction. 1855 */ 1856 div_op = strrchr(str, '/'); 1857 if (div_op) 1858 field_op = FIELD_OP_DIV; 1859 1860 mult_op = strrchr(str, '*'); 1861 /* 1862 * For operators of the same precedence use to rightmost as the 1863 * root, so that the expression is evaluated left to right. 1864 */ 1865 if (mult_op > div_op) 1866 field_op = FIELD_OP_MULT; 1867 1868 out: 1869 if (sep) { 1870 switch (field_op) { 1871 case FIELD_OP_UNARY_MINUS: 1872 case FIELD_OP_MINUS: 1873 *sep = minus_op; 1874 break; 1875 case FIELD_OP_PLUS: 1876 *sep = plus_op; 1877 break; 1878 case FIELD_OP_DIV: 1879 *sep = div_op; 1880 break; 1881 case FIELD_OP_MULT: 1882 *sep = mult_op; 1883 break; 1884 case FIELD_OP_NONE: 1885 default: 1886 *sep = NULL; 1887 break; 1888 } 1889 } 1890 1891 return field_op; 1892 } 1893 1894 static void get_hist_field(struct hist_field *hist_field) 1895 { 1896 hist_field->ref++; 1897 } 1898 1899 static void __destroy_hist_field(struct hist_field *hist_field) 1900 { 1901 if (--hist_field->ref > 1) 1902 return; 1903 1904 kfree(hist_field->var.name); 1905 kfree(hist_field->name); 1906 1907 /* Can likely be a const */ 1908 kfree_const(hist_field->type); 1909 1910 kfree(hist_field->system); 1911 kfree(hist_field->event_name); 1912 1913 kfree(hist_field); 1914 } 1915 1916 static void destroy_hist_field(struct hist_field *hist_field, 1917 unsigned int level) 1918 { 1919 unsigned int i; 1920 1921 if (level > 3) 1922 return; 1923 1924 if (!hist_field) 1925 return; 1926 1927 if (hist_field->flags & HIST_FIELD_FL_VAR_REF) 1928 return; /* var refs will be destroyed separately */ 1929 1930 for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++) 1931 destroy_hist_field(hist_field->operands[i], level + 1); 1932 1933 __destroy_hist_field(hist_field); 1934 } 1935 1936 static struct hist_field *create_hist_field(struct hist_trigger_data *hist_data, 1937 struct ftrace_event_field *field, 1938 unsigned long flags, 1939 char *var_name) 1940 { 1941 struct hist_field *hist_field; 1942 1943 if (field && is_function_field(field)) 1944 return NULL; 1945 1946 hist_field = kzalloc(sizeof(struct hist_field), GFP_KERNEL); 1947 if (!hist_field) 1948 return NULL; 1949 1950 hist_field->ref = 1; 1951 1952 hist_field->hist_data = hist_data; 1953 1954 if (flags & HIST_FIELD_FL_EXPR || flags & HIST_FIELD_FL_ALIAS) 1955 goto out; /* caller will populate */ 1956 1957 if (flags & HIST_FIELD_FL_VAR_REF) { 1958 hist_field->fn_num = HIST_FIELD_FN_VAR_REF; 1959 goto out; 1960 } 1961 1962 if (flags & HIST_FIELD_FL_HITCOUNT) { 1963 hist_field->fn_num = HIST_FIELD_FN_COUNTER; 1964 hist_field->size = sizeof(u64); 1965 hist_field->type = "u64"; 1966 goto out; 1967 } 1968 1969 if (flags & HIST_FIELD_FL_CONST) { 1970 hist_field->fn_num = HIST_FIELD_FN_CONST; 1971 hist_field->size = sizeof(u64); 1972 hist_field->type = kstrdup("u64", GFP_KERNEL); 1973 if (!hist_field->type) 1974 goto free; 1975 goto out; 1976 } 1977 1978 if (flags & HIST_FIELD_FL_STACKTRACE) { 1979 if (field) 1980 hist_field->fn_num = HIST_FIELD_FN_STACK; 1981 else 1982 hist_field->fn_num = HIST_FIELD_FN_NOP; 1983 hist_field->size = HIST_STACKTRACE_SIZE; 1984 hist_field->type = kstrdup_const("unsigned long[]", GFP_KERNEL); 1985 if (!hist_field->type) 1986 goto free; 1987 goto out; 1988 } 1989 1990 if (flags & (HIST_FIELD_FL_LOG2 | HIST_FIELD_FL_BUCKET)) { 1991 unsigned long fl = flags & ~(HIST_FIELD_FL_LOG2 | HIST_FIELD_FL_BUCKET); 1992 hist_field->fn_num = flags & HIST_FIELD_FL_LOG2 ? HIST_FIELD_FN_LOG2 : 1993 HIST_FIELD_FN_BUCKET; 1994 hist_field->operands[0] = create_hist_field(hist_data, field, fl, NULL); 1995 if (!hist_field->operands[0]) 1996 goto free; 1997 hist_field->size = hist_field->operands[0]->size; 1998 hist_field->type = kstrdup_const(hist_field->operands[0]->type, GFP_KERNEL); 1999 if (!hist_field->type) 2000 goto free; 2001 goto out; 2002 } 2003 2004 if (flags & HIST_FIELD_FL_TIMESTAMP) { 2005 hist_field->fn_num = HIST_FIELD_FN_TIMESTAMP; 2006 hist_field->size = sizeof(u64); 2007 hist_field->type = "u64"; 2008 goto out; 2009 } 2010 2011 if (flags & HIST_FIELD_FL_CPU) { 2012 hist_field->fn_num = HIST_FIELD_FN_CPU; 2013 hist_field->size = sizeof(int); 2014 hist_field->type = "unsigned int"; 2015 goto out; 2016 } 2017 2018 if (WARN_ON_ONCE(!field)) 2019 goto out; 2020 2021 /* Pointers to strings are just pointers and dangerous to dereference */ 2022 if (is_string_field(field) && 2023 (field->filter_type != FILTER_PTR_STRING)) { 2024 flags |= HIST_FIELD_FL_STRING; 2025 2026 hist_field->size = MAX_FILTER_STR_VAL; 2027 hist_field->type = kstrdup_const(field->type, GFP_KERNEL); 2028 if (!hist_field->type) 2029 goto free; 2030 2031 if (field->filter_type == FILTER_STATIC_STRING) { 2032 hist_field->fn_num = HIST_FIELD_FN_STRING; 2033 hist_field->size = field->size; 2034 } else if (field->filter_type == FILTER_DYN_STRING) { 2035 hist_field->fn_num = HIST_FIELD_FN_DYNSTRING; 2036 } else if (field->filter_type == FILTER_RDYN_STRING) 2037 hist_field->fn_num = HIST_FIELD_FN_RELDYNSTRING; 2038 else 2039 hist_field->fn_num = HIST_FIELD_FN_PSTRING; 2040 } else { 2041 hist_field->size = field->size; 2042 hist_field->is_signed = field->is_signed; 2043 hist_field->type = kstrdup_const(field->type, GFP_KERNEL); 2044 if (!hist_field->type) 2045 goto free; 2046 2047 hist_field->fn_num = select_value_fn(field->size, 2048 field->is_signed); 2049 if (hist_field->fn_num == HIST_FIELD_FN_NOP) { 2050 destroy_hist_field(hist_field, 0); 2051 return NULL; 2052 } 2053 } 2054 out: 2055 hist_field->field = field; 2056 hist_field->flags = flags; 2057 2058 if (var_name) { 2059 hist_field->var.name = kstrdup(var_name, GFP_KERNEL); 2060 if (!hist_field->var.name) 2061 goto free; 2062 } 2063 2064 return hist_field; 2065 free: 2066 destroy_hist_field(hist_field, 0); 2067 return NULL; 2068 } 2069 2070 static void destroy_hist_fields(struct hist_trigger_data *hist_data) 2071 { 2072 unsigned int i; 2073 2074 for (i = 0; i < HIST_FIELDS_MAX; i++) { 2075 if (hist_data->fields[i]) { 2076 destroy_hist_field(hist_data->fields[i], 0); 2077 hist_data->fields[i] = NULL; 2078 } 2079 } 2080 2081 for (i = 0; i < hist_data->n_var_refs; i++) { 2082 WARN_ON(!(hist_data->var_refs[i]->flags & HIST_FIELD_FL_VAR_REF)); 2083 __destroy_hist_field(hist_data->var_refs[i]); 2084 hist_data->var_refs[i] = NULL; 2085 } 2086 } 2087 2088 static int init_var_ref(struct hist_field *ref_field, 2089 struct hist_field *var_field, 2090 char *system, char *event_name) 2091 { 2092 int err = 0; 2093 2094 ref_field->var.idx = var_field->var.idx; 2095 ref_field->var.hist_data = var_field->hist_data; 2096 ref_field->size = var_field->size; 2097 ref_field->is_signed = var_field->is_signed; 2098 ref_field->flags |= var_field->flags & 2099 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS); 2100 2101 if (system) { 2102 ref_field->system = kstrdup(system, GFP_KERNEL); 2103 if (!ref_field->system) 2104 return -ENOMEM; 2105 } 2106 2107 if (event_name) { 2108 ref_field->event_name = kstrdup(event_name, GFP_KERNEL); 2109 if (!ref_field->event_name) { 2110 err = -ENOMEM; 2111 goto free; 2112 } 2113 } 2114 2115 if (var_field->var.name) { 2116 ref_field->name = kstrdup(var_field->var.name, GFP_KERNEL); 2117 if (!ref_field->name) { 2118 err = -ENOMEM; 2119 goto free; 2120 } 2121 } else if (var_field->name) { 2122 ref_field->name = kstrdup(var_field->name, GFP_KERNEL); 2123 if (!ref_field->name) { 2124 err = -ENOMEM; 2125 goto free; 2126 } 2127 } 2128 2129 ref_field->type = kstrdup_const(var_field->type, GFP_KERNEL); 2130 if (!ref_field->type) { 2131 err = -ENOMEM; 2132 goto free; 2133 } 2134 out: 2135 return err; 2136 free: 2137 kfree(ref_field->system); 2138 ref_field->system = NULL; 2139 kfree(ref_field->event_name); 2140 ref_field->event_name = NULL; 2141 kfree(ref_field->name); 2142 ref_field->name = NULL; 2143 2144 goto out; 2145 } 2146 2147 static int find_var_ref_idx(struct hist_trigger_data *hist_data, 2148 struct hist_field *var_field) 2149 { 2150 struct hist_field *ref_field; 2151 int i; 2152 2153 for (i = 0; i < hist_data->n_var_refs; i++) { 2154 ref_field = hist_data->var_refs[i]; 2155 if (ref_field->var.idx == var_field->var.idx && 2156 ref_field->var.hist_data == var_field->hist_data) 2157 return i; 2158 } 2159 2160 return -ENOENT; 2161 } 2162 2163 /** 2164 * create_var_ref - Create a variable reference and attach it to trigger 2165 * @hist_data: The trigger that will be referencing the variable 2166 * @var_field: The VAR field to create a reference to 2167 * @system: The optional system string 2168 * @event_name: The optional event_name string 2169 * 2170 * Given a variable hist_field, create a VAR_REF hist_field that 2171 * represents a reference to it. 2172 * 2173 * This function also adds the reference to the trigger that 2174 * now references the variable. 2175 * 2176 * Return: The VAR_REF field if successful, NULL if not 2177 */ 2178 static struct hist_field *create_var_ref(struct hist_trigger_data *hist_data, 2179 struct hist_field *var_field, 2180 char *system, char *event_name) 2181 { 2182 unsigned long flags = HIST_FIELD_FL_VAR_REF; 2183 struct hist_field *ref_field; 2184 int i; 2185 2186 /* Check if the variable already exists */ 2187 for (i = 0; i < hist_data->n_var_refs; i++) { 2188 ref_field = hist_data->var_refs[i]; 2189 if (ref_field->var.idx == var_field->var.idx && 2190 ref_field->var.hist_data == var_field->hist_data) { 2191 get_hist_field(ref_field); 2192 return ref_field; 2193 } 2194 } 2195 /* Sanity check to avoid out-of-bound write on 'hist_data->var_refs' */ 2196 if (hist_data->n_var_refs >= TRACING_MAP_VARS_MAX) 2197 return NULL; 2198 ref_field = create_hist_field(var_field->hist_data, NULL, flags, NULL); 2199 if (ref_field) { 2200 if (init_var_ref(ref_field, var_field, system, event_name)) { 2201 destroy_hist_field(ref_field, 0); 2202 return NULL; 2203 } 2204 2205 hist_data->var_refs[hist_data->n_var_refs] = ref_field; 2206 ref_field->var_ref_idx = hist_data->n_var_refs++; 2207 } 2208 2209 return ref_field; 2210 } 2211 2212 static bool is_var_ref(char *var_name) 2213 { 2214 if (!var_name || strlen(var_name) < 2 || var_name[0] != '$') 2215 return false; 2216 2217 return true; 2218 } 2219 2220 static char *field_name_from_var(struct hist_trigger_data *hist_data, 2221 char *var_name) 2222 { 2223 char *name, *field; 2224 unsigned int i; 2225 2226 for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) { 2227 name = hist_data->attrs->var_defs.name[i]; 2228 2229 if (strcmp(var_name, name) == 0) { 2230 field = hist_data->attrs->var_defs.expr[i]; 2231 if (contains_operator(field, NULL) || is_var_ref(field)) 2232 continue; 2233 return field; 2234 } 2235 } 2236 2237 return NULL; 2238 } 2239 2240 static char *local_field_var_ref(struct hist_trigger_data *hist_data, 2241 char *system, char *event_name, 2242 char *var_name) 2243 { 2244 struct trace_event_call *call; 2245 2246 if (system && event_name) { 2247 call = hist_data->event_file->event_call; 2248 2249 if (strcmp(system, call->class->system) != 0) 2250 return NULL; 2251 2252 if (strcmp(event_name, trace_event_name(call)) != 0) 2253 return NULL; 2254 } 2255 2256 if (!!system != !!event_name) 2257 return NULL; 2258 2259 if (!is_var_ref(var_name)) 2260 return NULL; 2261 2262 var_name++; 2263 2264 return field_name_from_var(hist_data, var_name); 2265 } 2266 2267 static struct hist_field *parse_var_ref(struct hist_trigger_data *hist_data, 2268 char *system, char *event_name, 2269 char *var_name) 2270 { 2271 struct hist_field *var_field = NULL, *ref_field = NULL; 2272 struct trace_array *tr = hist_data->event_file->tr; 2273 2274 if (!is_var_ref(var_name)) 2275 return NULL; 2276 2277 var_name++; 2278 2279 var_field = find_event_var(hist_data, system, event_name, var_name); 2280 if (var_field) 2281 ref_field = create_var_ref(hist_data, var_field, 2282 system, event_name); 2283 2284 if (!ref_field) 2285 hist_err(tr, HIST_ERR_VAR_NOT_FOUND, errpos(var_name)); 2286 2287 return ref_field; 2288 } 2289 2290 static struct ftrace_event_field * 2291 parse_field(struct hist_trigger_data *hist_data, struct trace_event_file *file, 2292 char *field_str, unsigned long *flags, unsigned long *buckets) 2293 { 2294 struct ftrace_event_field *field = NULL; 2295 char *field_name, *modifier, *str; 2296 struct trace_array *tr = file->tr; 2297 2298 modifier = str = kstrdup(field_str, GFP_KERNEL); 2299 if (!modifier) 2300 return ERR_PTR(-ENOMEM); 2301 2302 field_name = strsep(&modifier, "."); 2303 if (modifier) { 2304 if (strcmp(modifier, "hex") == 0) 2305 *flags |= HIST_FIELD_FL_HEX; 2306 else if (strcmp(modifier, "sym") == 0) 2307 *flags |= HIST_FIELD_FL_SYM; 2308 /* 2309 * 'sym-offset' occurrences in the trigger string are modified 2310 * to 'symXoffset' to simplify arithmetic expression parsing. 2311 */ 2312 else if (strcmp(modifier, "symXoffset") == 0) 2313 *flags |= HIST_FIELD_FL_SYM_OFFSET; 2314 else if ((strcmp(modifier, "execname") == 0) && 2315 (strcmp(field_name, "common_pid") == 0)) 2316 *flags |= HIST_FIELD_FL_EXECNAME; 2317 else if (strcmp(modifier, "syscall") == 0) 2318 *flags |= HIST_FIELD_FL_SYSCALL; 2319 else if (strcmp(modifier, "stacktrace") == 0) 2320 *flags |= HIST_FIELD_FL_STACKTRACE; 2321 else if (strcmp(modifier, "log2") == 0) 2322 *flags |= HIST_FIELD_FL_LOG2; 2323 else if (strcmp(modifier, "usecs") == 0) 2324 *flags |= HIST_FIELD_FL_TIMESTAMP_USECS; 2325 else if (strncmp(modifier, "bucket", 6) == 0) { 2326 int ret; 2327 2328 modifier += 6; 2329 2330 if (*modifier == 's') 2331 modifier++; 2332 if (*modifier != '=') 2333 goto error; 2334 modifier++; 2335 ret = kstrtoul(modifier, 0, buckets); 2336 if (ret || !(*buckets)) 2337 goto error; 2338 *flags |= HIST_FIELD_FL_BUCKET; 2339 } else if (strncmp(modifier, "percent", 7) == 0) { 2340 if (*flags & (HIST_FIELD_FL_VAR | HIST_FIELD_FL_KEY)) 2341 goto error; 2342 *flags |= HIST_FIELD_FL_PERCENT; 2343 } else if (strncmp(modifier, "graph", 5) == 0) { 2344 if (*flags & (HIST_FIELD_FL_VAR | HIST_FIELD_FL_KEY)) 2345 goto error; 2346 *flags |= HIST_FIELD_FL_GRAPH; 2347 } else { 2348 error: 2349 hist_err(tr, HIST_ERR_BAD_FIELD_MODIFIER, errpos(modifier)); 2350 field = ERR_PTR(-EINVAL); 2351 goto out; 2352 } 2353 } 2354 2355 if (strcmp(field_name, "common_timestamp") == 0) { 2356 *flags |= HIST_FIELD_FL_TIMESTAMP; 2357 hist_data->enable_timestamps = true; 2358 if (*flags & HIST_FIELD_FL_TIMESTAMP_USECS) 2359 hist_data->attrs->ts_in_usecs = true; 2360 } else if (strcmp(field_name, "common_stacktrace") == 0) { 2361 *flags |= HIST_FIELD_FL_STACKTRACE; 2362 } else if (strcmp(field_name, "common_cpu") == 0) 2363 *flags |= HIST_FIELD_FL_CPU; 2364 else if (strcmp(field_name, "hitcount") == 0) 2365 *flags |= HIST_FIELD_FL_HITCOUNT; 2366 else { 2367 field = trace_find_event_field(file->event_call, field_name); 2368 if (!field || !field->size) { 2369 /* 2370 * For backward compatibility, if field_name 2371 * was "cpu" or "stacktrace", then we treat this 2372 * the same as common_cpu and common_stacktrace 2373 * respectively. This also works for "CPU", and 2374 * "STACKTRACE". 2375 */ 2376 if (field && field->filter_type == FILTER_CPU) { 2377 *flags |= HIST_FIELD_FL_CPU; 2378 } else if (field && field->filter_type == FILTER_STACKTRACE) { 2379 *flags |= HIST_FIELD_FL_STACKTRACE; 2380 } else { 2381 hist_err(tr, HIST_ERR_FIELD_NOT_FOUND, 2382 errpos(field_name)); 2383 field = ERR_PTR(-EINVAL); 2384 goto out; 2385 } 2386 } 2387 } 2388 out: 2389 kfree(str); 2390 2391 return field; 2392 } 2393 2394 static struct hist_field *create_alias(struct hist_trigger_data *hist_data, 2395 struct hist_field *var_ref, 2396 char *var_name) 2397 { 2398 struct hist_field *alias = NULL; 2399 unsigned long flags = HIST_FIELD_FL_ALIAS | HIST_FIELD_FL_VAR; 2400 2401 alias = create_hist_field(hist_data, NULL, flags, var_name); 2402 if (!alias) 2403 return NULL; 2404 2405 alias->fn_num = var_ref->fn_num; 2406 alias->operands[0] = var_ref; 2407 2408 if (init_var_ref(alias, var_ref, var_ref->system, var_ref->event_name)) { 2409 destroy_hist_field(alias, 0); 2410 return NULL; 2411 } 2412 2413 alias->var_ref_idx = var_ref->var_ref_idx; 2414 2415 return alias; 2416 } 2417 2418 static struct hist_field *parse_const(struct hist_trigger_data *hist_data, 2419 char *str, char *var_name, 2420 unsigned long *flags) 2421 { 2422 struct trace_array *tr = hist_data->event_file->tr; 2423 struct hist_field *field = NULL; 2424 u64 constant; 2425 2426 if (kstrtoull(str, 0, &constant)) { 2427 hist_err(tr, HIST_ERR_EXPECT_NUMBER, errpos(str)); 2428 return NULL; 2429 } 2430 2431 *flags |= HIST_FIELD_FL_CONST; 2432 field = create_hist_field(hist_data, NULL, *flags, var_name); 2433 if (!field) 2434 return NULL; 2435 2436 field->constant = constant; 2437 2438 return field; 2439 } 2440 2441 static struct hist_field *parse_atom(struct hist_trigger_data *hist_data, 2442 struct trace_event_file *file, char *str, 2443 unsigned long *flags, char *var_name) 2444 { 2445 char *s, *ref_system = NULL, *ref_event = NULL, *ref_var = str; 2446 struct ftrace_event_field *field = NULL; 2447 struct hist_field *hist_field = NULL; 2448 unsigned long buckets = 0; 2449 int ret = 0; 2450 2451 if (isdigit(str[0])) { 2452 hist_field = parse_const(hist_data, str, var_name, flags); 2453 if (!hist_field) { 2454 ret = -EINVAL; 2455 goto out; 2456 } 2457 return hist_field; 2458 } 2459 2460 s = strchr(str, '.'); 2461 if (s) { 2462 s = strchr(++s, '.'); 2463 if (s) { 2464 ref_system = strsep(&str, "."); 2465 if (!str) { 2466 ret = -EINVAL; 2467 goto out; 2468 } 2469 ref_event = strsep(&str, "."); 2470 if (!str) { 2471 ret = -EINVAL; 2472 goto out; 2473 } 2474 ref_var = str; 2475 } 2476 } 2477 2478 s = local_field_var_ref(hist_data, ref_system, ref_event, ref_var); 2479 if (!s) { 2480 hist_field = parse_var_ref(hist_data, ref_system, 2481 ref_event, ref_var); 2482 if (hist_field) { 2483 if (var_name) { 2484 hist_field = create_alias(hist_data, hist_field, var_name); 2485 if (!hist_field) { 2486 ret = -ENOMEM; 2487 goto out; 2488 } 2489 } 2490 return hist_field; 2491 } 2492 } else 2493 str = s; 2494 2495 field = parse_field(hist_data, file, str, flags, &buckets); 2496 if (IS_ERR(field)) { 2497 ret = PTR_ERR(field); 2498 goto out; 2499 } 2500 2501 hist_field = create_hist_field(hist_data, field, *flags, var_name); 2502 if (!hist_field) { 2503 ret = -ENOMEM; 2504 goto out; 2505 } 2506 hist_field->buckets = buckets; 2507 2508 return hist_field; 2509 out: 2510 return ERR_PTR(ret); 2511 } 2512 2513 static struct hist_field *parse_expr(struct hist_trigger_data *hist_data, 2514 struct trace_event_file *file, 2515 char *str, unsigned long flags, 2516 char *var_name, unsigned int *n_subexprs); 2517 2518 static struct hist_field *parse_unary(struct hist_trigger_data *hist_data, 2519 struct trace_event_file *file, 2520 char *str, unsigned long flags, 2521 char *var_name, unsigned int *n_subexprs) 2522 { 2523 struct hist_field *operand1, *expr = NULL; 2524 unsigned long operand_flags; 2525 int ret = 0; 2526 char *s; 2527 2528 /* Unary minus operator, increment n_subexprs */ 2529 ++*n_subexprs; 2530 2531 /* we support only -(xxx) i.e. explicit parens required */ 2532 2533 if (*n_subexprs > 3) { 2534 hist_err(file->tr, HIST_ERR_TOO_MANY_SUBEXPR, errpos(str)); 2535 ret = -EINVAL; 2536 goto free; 2537 } 2538 2539 str++; /* skip leading '-' */ 2540 2541 s = strchr(str, '('); 2542 if (s) 2543 str++; 2544 else { 2545 ret = -EINVAL; 2546 goto free; 2547 } 2548 2549 s = strrchr(str, ')'); 2550 if (s) { 2551 /* unary minus not supported in sub-expressions */ 2552 if (*(s+1) != '\0') { 2553 hist_err(file->tr, HIST_ERR_UNARY_MINUS_SUBEXPR, 2554 errpos(str)); 2555 ret = -EINVAL; 2556 goto free; 2557 } 2558 *s = '\0'; 2559 } 2560 else { 2561 ret = -EINVAL; /* no closing ')' */ 2562 goto free; 2563 } 2564 2565 flags |= HIST_FIELD_FL_EXPR; 2566 expr = create_hist_field(hist_data, NULL, flags, var_name); 2567 if (!expr) { 2568 ret = -ENOMEM; 2569 goto free; 2570 } 2571 2572 operand_flags = 0; 2573 operand1 = parse_expr(hist_data, file, str, operand_flags, NULL, n_subexprs); 2574 if (IS_ERR(operand1)) { 2575 ret = PTR_ERR(operand1); 2576 goto free; 2577 } 2578 if (operand1->flags & HIST_FIELD_FL_STRING) { 2579 /* String type can not be the operand of unary operator. */ 2580 hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(str)); 2581 destroy_hist_field(operand1, 0); 2582 ret = -EINVAL; 2583 goto free; 2584 } 2585 2586 expr->flags |= operand1->flags & 2587 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS); 2588 expr->fn_num = HIST_FIELD_FN_UMINUS; 2589 expr->operands[0] = operand1; 2590 expr->size = operand1->size; 2591 expr->is_signed = operand1->is_signed; 2592 expr->operator = FIELD_OP_UNARY_MINUS; 2593 expr->name = expr_str(expr, 0); 2594 expr->type = kstrdup_const(operand1->type, GFP_KERNEL); 2595 if (!expr->type) { 2596 ret = -ENOMEM; 2597 goto free; 2598 } 2599 2600 return expr; 2601 free: 2602 destroy_hist_field(expr, 0); 2603 return ERR_PTR(ret); 2604 } 2605 2606 /* 2607 * If the operands are var refs, return pointers the 2608 * variable(s) referenced in var1 and var2, else NULL. 2609 */ 2610 static int check_expr_operands(struct trace_array *tr, 2611 struct hist_field *operand1, 2612 struct hist_field *operand2, 2613 struct hist_field **var1, 2614 struct hist_field **var2) 2615 { 2616 unsigned long operand1_flags = operand1->flags; 2617 unsigned long operand2_flags = operand2->flags; 2618 2619 if ((operand1_flags & HIST_FIELD_FL_VAR_REF) || 2620 (operand1_flags & HIST_FIELD_FL_ALIAS)) { 2621 struct hist_field *var; 2622 2623 var = find_var_field(operand1->var.hist_data, operand1->name); 2624 if (!var) 2625 return -EINVAL; 2626 operand1_flags = var->flags; 2627 *var1 = var; 2628 } 2629 2630 if ((operand2_flags & HIST_FIELD_FL_VAR_REF) || 2631 (operand2_flags & HIST_FIELD_FL_ALIAS)) { 2632 struct hist_field *var; 2633 2634 var = find_var_field(operand2->var.hist_data, operand2->name); 2635 if (!var) 2636 return -EINVAL; 2637 operand2_flags = var->flags; 2638 *var2 = var; 2639 } 2640 2641 if ((operand1_flags & HIST_FIELD_FL_TIMESTAMP_USECS) != 2642 (operand2_flags & HIST_FIELD_FL_TIMESTAMP_USECS)) { 2643 hist_err(tr, HIST_ERR_TIMESTAMP_MISMATCH, 0); 2644 return -EINVAL; 2645 } 2646 2647 return 0; 2648 } 2649 2650 static struct hist_field *parse_expr(struct hist_trigger_data *hist_data, 2651 struct trace_event_file *file, 2652 char *str, unsigned long flags, 2653 char *var_name, unsigned int *n_subexprs) 2654 { 2655 struct hist_field *operand1 = NULL, *operand2 = NULL, *expr = NULL; 2656 struct hist_field *var1 = NULL, *var2 = NULL; 2657 unsigned long operand_flags, operand2_flags; 2658 int field_op, ret = -EINVAL; 2659 char *sep, *operand1_str; 2660 enum hist_field_fn op_fn; 2661 bool combine_consts; 2662 2663 if (*n_subexprs > 3) { 2664 hist_err(file->tr, HIST_ERR_TOO_MANY_SUBEXPR, errpos(str)); 2665 return ERR_PTR(-EINVAL); 2666 } 2667 2668 field_op = contains_operator(str, &sep); 2669 2670 if (field_op == FIELD_OP_NONE) 2671 return parse_atom(hist_data, file, str, &flags, var_name); 2672 2673 if (field_op == FIELD_OP_UNARY_MINUS) 2674 return parse_unary(hist_data, file, str, flags, var_name, n_subexprs); 2675 2676 /* Binary operator found, increment n_subexprs */ 2677 ++*n_subexprs; 2678 2679 /* Split the expression string at the root operator */ 2680 if (!sep) 2681 return ERR_PTR(-EINVAL); 2682 2683 *sep = '\0'; 2684 operand1_str = str; 2685 str = sep+1; 2686 2687 /* Binary operator requires both operands */ 2688 if (*operand1_str == '\0' || *str == '\0') 2689 return ERR_PTR(-EINVAL); 2690 2691 operand_flags = 0; 2692 2693 /* LHS of string is an expression e.g. a+b in a+b+c */ 2694 operand1 = parse_expr(hist_data, file, operand1_str, operand_flags, NULL, n_subexprs); 2695 if (IS_ERR(operand1)) 2696 return ERR_CAST(operand1); 2697 2698 if (operand1->flags & HIST_FIELD_FL_STRING) { 2699 hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(operand1_str)); 2700 ret = -EINVAL; 2701 goto free_op1; 2702 } 2703 2704 /* RHS of string is another expression e.g. c in a+b+c */ 2705 operand_flags = 0; 2706 operand2 = parse_expr(hist_data, file, str, operand_flags, NULL, n_subexprs); 2707 if (IS_ERR(operand2)) { 2708 ret = PTR_ERR(operand2); 2709 goto free_op1; 2710 } 2711 if (operand2->flags & HIST_FIELD_FL_STRING) { 2712 hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(str)); 2713 ret = -EINVAL; 2714 goto free_operands; 2715 } 2716 2717 switch (field_op) { 2718 case FIELD_OP_MINUS: 2719 op_fn = HIST_FIELD_FN_MINUS; 2720 break; 2721 case FIELD_OP_PLUS: 2722 op_fn = HIST_FIELD_FN_PLUS; 2723 break; 2724 case FIELD_OP_DIV: 2725 op_fn = HIST_FIELD_FN_DIV; 2726 break; 2727 case FIELD_OP_MULT: 2728 op_fn = HIST_FIELD_FN_MULT; 2729 break; 2730 default: 2731 ret = -EINVAL; 2732 goto free_operands; 2733 } 2734 2735 ret = check_expr_operands(file->tr, operand1, operand2, &var1, &var2); 2736 if (ret) 2737 goto free_operands; 2738 2739 operand_flags = var1 ? var1->flags : operand1->flags; 2740 operand2_flags = var2 ? var2->flags : operand2->flags; 2741 2742 /* 2743 * If both operands are constant, the expression can be 2744 * collapsed to a single constant. 2745 */ 2746 combine_consts = operand_flags & operand2_flags & HIST_FIELD_FL_CONST; 2747 2748 flags |= combine_consts ? HIST_FIELD_FL_CONST : HIST_FIELD_FL_EXPR; 2749 2750 flags |= operand1->flags & 2751 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS); 2752 2753 expr = create_hist_field(hist_data, NULL, flags, var_name); 2754 if (!expr) { 2755 ret = -ENOMEM; 2756 goto free_operands; 2757 } 2758 2759 operand1->read_once = true; 2760 operand2->read_once = true; 2761 2762 /* The operands are now owned and free'd by 'expr' */ 2763 expr->operands[0] = operand1; 2764 expr->operands[1] = operand2; 2765 2766 if (field_op == FIELD_OP_DIV && 2767 operand2_flags & HIST_FIELD_FL_CONST) { 2768 u64 divisor = var2 ? var2->constant : operand2->constant; 2769 2770 if (!divisor) { 2771 hist_err(file->tr, HIST_ERR_DIVISION_BY_ZERO, errpos(str)); 2772 ret = -EDOM; 2773 goto free_expr; 2774 } 2775 2776 /* 2777 * Copy the divisor here so we don't have to look it up 2778 * later if this is a var ref 2779 */ 2780 operand2->constant = divisor; 2781 op_fn = hist_field_get_div_fn(operand2); 2782 } 2783 2784 expr->fn_num = op_fn; 2785 2786 if (combine_consts) { 2787 if (var1) 2788 expr->operands[0] = var1; 2789 if (var2) 2790 expr->operands[1] = var2; 2791 2792 expr->constant = hist_fn_call(expr, NULL, NULL, NULL, NULL); 2793 expr->fn_num = HIST_FIELD_FN_CONST; 2794 2795 expr->operands[0] = NULL; 2796 expr->operands[1] = NULL; 2797 2798 /* 2799 * var refs won't be destroyed immediately 2800 * See: destroy_hist_field() 2801 */ 2802 destroy_hist_field(operand2, 0); 2803 destroy_hist_field(operand1, 0); 2804 2805 expr->name = expr_str(expr, 0); 2806 } else { 2807 /* The operand sizes should be the same, so just pick one */ 2808 expr->size = operand1->size; 2809 expr->is_signed = operand1->is_signed; 2810 2811 expr->operator = field_op; 2812 expr->type = kstrdup_const(operand1->type, GFP_KERNEL); 2813 if (!expr->type) { 2814 ret = -ENOMEM; 2815 goto free_expr; 2816 } 2817 2818 expr->name = expr_str(expr, 0); 2819 } 2820 2821 return expr; 2822 2823 free_operands: 2824 destroy_hist_field(operand2, 0); 2825 free_op1: 2826 destroy_hist_field(operand1, 0); 2827 return ERR_PTR(ret); 2828 2829 free_expr: 2830 destroy_hist_field(expr, 0); 2831 return ERR_PTR(ret); 2832 } 2833 2834 static char *find_trigger_filter(struct hist_trigger_data *hist_data, 2835 struct trace_event_file *file) 2836 { 2837 struct event_trigger_data *test; 2838 2839 lockdep_assert_held(&event_mutex); 2840 2841 list_for_each_entry(test, &file->triggers, list) { 2842 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 2843 if (test->private_data == hist_data) 2844 return test->filter_str; 2845 } 2846 } 2847 2848 return NULL; 2849 } 2850 2851 static struct event_command trigger_hist_cmd; 2852 static int event_hist_trigger_parse(struct event_command *cmd_ops, 2853 struct trace_event_file *file, 2854 char *glob, char *cmd, 2855 char *param_and_filter); 2856 2857 static bool compatible_keys(struct hist_trigger_data *target_hist_data, 2858 struct hist_trigger_data *hist_data, 2859 unsigned int n_keys) 2860 { 2861 struct hist_field *target_hist_field, *hist_field; 2862 unsigned int n, i, j; 2863 2864 if (hist_data->n_fields - hist_data->n_vals != n_keys) 2865 return false; 2866 2867 i = hist_data->n_vals; 2868 j = target_hist_data->n_vals; 2869 2870 for (n = 0; n < n_keys; n++) { 2871 hist_field = hist_data->fields[i + n]; 2872 target_hist_field = target_hist_data->fields[j + n]; 2873 2874 if (strcmp(hist_field->type, target_hist_field->type) != 0) 2875 return false; 2876 if (hist_field->size != target_hist_field->size) 2877 return false; 2878 if (hist_field->is_signed != target_hist_field->is_signed) 2879 return false; 2880 } 2881 2882 return true; 2883 } 2884 2885 static struct hist_trigger_data * 2886 find_compatible_hist(struct hist_trigger_data *target_hist_data, 2887 struct trace_event_file *file) 2888 { 2889 struct hist_trigger_data *hist_data; 2890 struct event_trigger_data *test; 2891 unsigned int n_keys; 2892 2893 lockdep_assert_held(&event_mutex); 2894 2895 n_keys = target_hist_data->n_fields - target_hist_data->n_vals; 2896 2897 list_for_each_entry(test, &file->triggers, list) { 2898 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 2899 hist_data = test->private_data; 2900 2901 if (compatible_keys(target_hist_data, hist_data, n_keys)) 2902 return hist_data; 2903 } 2904 } 2905 2906 return NULL; 2907 } 2908 2909 static struct trace_event_file *event_file(struct trace_array *tr, 2910 char *system, char *event_name) 2911 { 2912 struct trace_event_file *file; 2913 2914 file = __find_event_file(tr, system, event_name); 2915 if (!file) 2916 return ERR_PTR(-EINVAL); 2917 2918 return file; 2919 } 2920 2921 static struct hist_field * 2922 find_synthetic_field_var(struct hist_trigger_data *target_hist_data, 2923 char *system, char *event_name, char *field_name) 2924 { 2925 struct hist_field *event_var; 2926 char *synthetic_name; 2927 2928 synthetic_name = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL); 2929 if (!synthetic_name) 2930 return ERR_PTR(-ENOMEM); 2931 2932 strcpy(synthetic_name, "synthetic_"); 2933 strcat(synthetic_name, field_name); 2934 2935 event_var = find_event_var(target_hist_data, system, event_name, synthetic_name); 2936 2937 kfree(synthetic_name); 2938 2939 return event_var; 2940 } 2941 2942 /** 2943 * create_field_var_hist - Automatically create a histogram and var for a field 2944 * @target_hist_data: The target hist trigger 2945 * @subsys_name: Optional subsystem name 2946 * @event_name: Optional event name 2947 * @field_name: The name of the field (and the resulting variable) 2948 * 2949 * Hist trigger actions fetch data from variables, not directly from 2950 * events. However, for convenience, users are allowed to directly 2951 * specify an event field in an action, which will be automatically 2952 * converted into a variable on their behalf. 2953 * 2954 * If a user specifies a field on an event that isn't the event the 2955 * histogram currently being defined (the target event histogram), the 2956 * only way that can be accomplished is if a new hist trigger is 2957 * created and the field variable defined on that. 2958 * 2959 * This function creates a new histogram compatible with the target 2960 * event (meaning a histogram with the same key as the target 2961 * histogram), and creates a variable for the specified field, but 2962 * with 'synthetic_' prepended to the variable name in order to avoid 2963 * collision with normal field variables. 2964 * 2965 * Return: The variable created for the field. 2966 */ 2967 static struct hist_field * 2968 create_field_var_hist(struct hist_trigger_data *target_hist_data, 2969 char *subsys_name, char *event_name, char *field_name) 2970 { 2971 struct trace_array *tr = target_hist_data->event_file->tr; 2972 struct hist_trigger_data *hist_data; 2973 unsigned int i, n, first = true; 2974 struct field_var_hist *var_hist; 2975 struct trace_event_file *file; 2976 struct hist_field *key_field; 2977 struct hist_field *event_var; 2978 char *saved_filter; 2979 char *cmd; 2980 int ret; 2981 2982 if (target_hist_data->n_field_var_hists >= SYNTH_FIELDS_MAX) { 2983 hist_err(tr, HIST_ERR_TOO_MANY_FIELD_VARS, errpos(field_name)); 2984 return ERR_PTR(-EINVAL); 2985 } 2986 2987 file = event_file(tr, subsys_name, event_name); 2988 2989 if (IS_ERR(file)) { 2990 hist_err(tr, HIST_ERR_EVENT_FILE_NOT_FOUND, errpos(field_name)); 2991 ret = PTR_ERR(file); 2992 return ERR_PTR(ret); 2993 } 2994 2995 /* 2996 * Look for a histogram compatible with target. We'll use the 2997 * found histogram specification to create a new matching 2998 * histogram with our variable on it. target_hist_data is not 2999 * yet a registered histogram so we can't use that. 3000 */ 3001 hist_data = find_compatible_hist(target_hist_data, file); 3002 if (!hist_data) { 3003 hist_err(tr, HIST_ERR_HIST_NOT_FOUND, errpos(field_name)); 3004 return ERR_PTR(-EINVAL); 3005 } 3006 3007 /* See if a synthetic field variable has already been created */ 3008 event_var = find_synthetic_field_var(target_hist_data, subsys_name, 3009 event_name, field_name); 3010 if (!IS_ERR_OR_NULL(event_var)) 3011 return event_var; 3012 3013 var_hist = kzalloc(sizeof(*var_hist), GFP_KERNEL); 3014 if (!var_hist) 3015 return ERR_PTR(-ENOMEM); 3016 3017 cmd = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL); 3018 if (!cmd) { 3019 kfree(var_hist); 3020 return ERR_PTR(-ENOMEM); 3021 } 3022 3023 /* Use the same keys as the compatible histogram */ 3024 strcat(cmd, "keys="); 3025 3026 for_each_hist_key_field(i, hist_data) { 3027 key_field = hist_data->fields[i]; 3028 if (!first) 3029 strcat(cmd, ","); 3030 strcat(cmd, key_field->field->name); 3031 first = false; 3032 } 3033 3034 /* Create the synthetic field variable specification */ 3035 strcat(cmd, ":synthetic_"); 3036 strcat(cmd, field_name); 3037 strcat(cmd, "="); 3038 strcat(cmd, field_name); 3039 3040 /* Use the same filter as the compatible histogram */ 3041 saved_filter = find_trigger_filter(hist_data, file); 3042 if (saved_filter) { 3043 strcat(cmd, " if "); 3044 strcat(cmd, saved_filter); 3045 } 3046 3047 var_hist->cmd = kstrdup(cmd, GFP_KERNEL); 3048 if (!var_hist->cmd) { 3049 kfree(cmd); 3050 kfree(var_hist); 3051 return ERR_PTR(-ENOMEM); 3052 } 3053 3054 /* Save the compatible histogram information */ 3055 var_hist->hist_data = hist_data; 3056 3057 /* Create the new histogram with our variable */ 3058 ret = event_hist_trigger_parse(&trigger_hist_cmd, file, 3059 "", "hist", cmd); 3060 if (ret) { 3061 kfree(cmd); 3062 kfree(var_hist->cmd); 3063 kfree(var_hist); 3064 hist_err(tr, HIST_ERR_HIST_CREATE_FAIL, errpos(field_name)); 3065 return ERR_PTR(ret); 3066 } 3067 3068 kfree(cmd); 3069 3070 /* If we can't find the variable, something went wrong */ 3071 event_var = find_synthetic_field_var(target_hist_data, subsys_name, 3072 event_name, field_name); 3073 if (IS_ERR_OR_NULL(event_var)) { 3074 kfree(var_hist->cmd); 3075 kfree(var_hist); 3076 hist_err(tr, HIST_ERR_SYNTH_VAR_NOT_FOUND, errpos(field_name)); 3077 return ERR_PTR(-EINVAL); 3078 } 3079 3080 n = target_hist_data->n_field_var_hists; 3081 target_hist_data->field_var_hists[n] = var_hist; 3082 target_hist_data->n_field_var_hists++; 3083 3084 return event_var; 3085 } 3086 3087 static struct hist_field * 3088 find_target_event_var(struct hist_trigger_data *hist_data, 3089 char *subsys_name, char *event_name, char *var_name) 3090 { 3091 struct trace_event_file *file = hist_data->event_file; 3092 struct hist_field *hist_field = NULL; 3093 3094 if (subsys_name) { 3095 struct trace_event_call *call; 3096 3097 if (!event_name) 3098 return NULL; 3099 3100 call = file->event_call; 3101 3102 if (strcmp(subsys_name, call->class->system) != 0) 3103 return NULL; 3104 3105 if (strcmp(event_name, trace_event_name(call)) != 0) 3106 return NULL; 3107 } 3108 3109 hist_field = find_var_field(hist_data, var_name); 3110 3111 return hist_field; 3112 } 3113 3114 static inline void __update_field_vars(struct tracing_map_elt *elt, 3115 struct trace_buffer *buffer, 3116 struct ring_buffer_event *rbe, 3117 void *rec, 3118 struct field_var **field_vars, 3119 unsigned int n_field_vars, 3120 unsigned int field_var_str_start) 3121 { 3122 struct hist_elt_data *elt_data = elt->private_data; 3123 unsigned int i, j, var_idx; 3124 u64 var_val; 3125 3126 /* Make sure stacktrace can fit in the string variable length */ 3127 BUILD_BUG_ON((HIST_STACKTRACE_DEPTH + 1) * sizeof(long) >= STR_VAR_LEN_MAX); 3128 3129 for (i = 0, j = field_var_str_start; i < n_field_vars; i++) { 3130 struct field_var *field_var = field_vars[i]; 3131 struct hist_field *var = field_var->var; 3132 struct hist_field *val = field_var->val; 3133 3134 var_val = hist_fn_call(val, elt, buffer, rbe, rec); 3135 var_idx = var->var.idx; 3136 3137 if (val->flags & (HIST_FIELD_FL_STRING | 3138 HIST_FIELD_FL_STACKTRACE)) { 3139 char *str = elt_data->field_var_str[j++]; 3140 char *val_str = (char *)(uintptr_t)var_val; 3141 unsigned int size; 3142 3143 if (val->flags & HIST_FIELD_FL_STRING) { 3144 size = min(val->size, STR_VAR_LEN_MAX); 3145 strscpy(str, val_str, size); 3146 } else { 3147 char *stack_start = str + sizeof(unsigned long); 3148 int e; 3149 3150 e = stack_trace_save((void *)stack_start, 3151 HIST_STACKTRACE_DEPTH, 3152 HIST_STACKTRACE_SKIP); 3153 if (e < HIST_STACKTRACE_DEPTH - 1) 3154 ((unsigned long *)stack_start)[e] = 0; 3155 *((unsigned long *)str) = e; 3156 } 3157 var_val = (u64)(uintptr_t)str; 3158 } 3159 tracing_map_set_var(elt, var_idx, var_val); 3160 } 3161 } 3162 3163 static void update_field_vars(struct hist_trigger_data *hist_data, 3164 struct tracing_map_elt *elt, 3165 struct trace_buffer *buffer, 3166 struct ring_buffer_event *rbe, 3167 void *rec) 3168 { 3169 __update_field_vars(elt, buffer, rbe, rec, hist_data->field_vars, 3170 hist_data->n_field_vars, 0); 3171 } 3172 3173 static void save_track_data_vars(struct hist_trigger_data *hist_data, 3174 struct tracing_map_elt *elt, 3175 struct trace_buffer *buffer, void *rec, 3176 struct ring_buffer_event *rbe, void *key, 3177 struct action_data *data, u64 *var_ref_vals) 3178 { 3179 __update_field_vars(elt, buffer, rbe, rec, hist_data->save_vars, 3180 hist_data->n_save_vars, hist_data->n_field_var_str); 3181 } 3182 3183 static struct hist_field *create_var(struct hist_trigger_data *hist_data, 3184 struct trace_event_file *file, 3185 char *name, int size, const char *type) 3186 { 3187 struct hist_field *var; 3188 int idx; 3189 3190 if (find_var(hist_data, file, name) && !hist_data->remove) { 3191 var = ERR_PTR(-EINVAL); 3192 goto out; 3193 } 3194 3195 var = kzalloc(sizeof(struct hist_field), GFP_KERNEL); 3196 if (!var) { 3197 var = ERR_PTR(-ENOMEM); 3198 goto out; 3199 } 3200 3201 idx = tracing_map_add_var(hist_data->map); 3202 if (idx < 0) { 3203 kfree(var); 3204 var = ERR_PTR(-EINVAL); 3205 goto out; 3206 } 3207 3208 var->ref = 1; 3209 var->flags = HIST_FIELD_FL_VAR; 3210 var->var.idx = idx; 3211 var->var.hist_data = var->hist_data = hist_data; 3212 var->size = size; 3213 var->var.name = kstrdup(name, GFP_KERNEL); 3214 var->type = kstrdup_const(type, GFP_KERNEL); 3215 if (!var->var.name || !var->type) { 3216 kfree_const(var->type); 3217 kfree(var->var.name); 3218 kfree(var); 3219 var = ERR_PTR(-ENOMEM); 3220 } 3221 out: 3222 return var; 3223 } 3224 3225 static struct field_var *create_field_var(struct hist_trigger_data *hist_data, 3226 struct trace_event_file *file, 3227 char *field_name) 3228 { 3229 struct hist_field *val = NULL, *var = NULL; 3230 unsigned long flags = HIST_FIELD_FL_VAR; 3231 struct trace_array *tr = file->tr; 3232 struct field_var *field_var; 3233 int ret = 0; 3234 3235 if (hist_data->n_field_vars >= SYNTH_FIELDS_MAX) { 3236 hist_err(tr, HIST_ERR_TOO_MANY_FIELD_VARS, errpos(field_name)); 3237 ret = -EINVAL; 3238 goto err; 3239 } 3240 3241 val = parse_atom(hist_data, file, field_name, &flags, NULL); 3242 if (IS_ERR(val)) { 3243 hist_err(tr, HIST_ERR_FIELD_VAR_PARSE_FAIL, errpos(field_name)); 3244 ret = PTR_ERR(val); 3245 goto err; 3246 } 3247 3248 var = create_var(hist_data, file, field_name, val->size, val->type); 3249 if (IS_ERR(var)) { 3250 hist_err(tr, HIST_ERR_VAR_CREATE_FIND_FAIL, errpos(field_name)); 3251 kfree(val); 3252 ret = PTR_ERR(var); 3253 goto err; 3254 } 3255 3256 field_var = kzalloc(sizeof(struct field_var), GFP_KERNEL); 3257 if (!field_var) { 3258 kfree(val); 3259 kfree(var); 3260 ret = -ENOMEM; 3261 goto err; 3262 } 3263 3264 field_var->var = var; 3265 field_var->val = val; 3266 out: 3267 return field_var; 3268 err: 3269 field_var = ERR_PTR(ret); 3270 goto out; 3271 } 3272 3273 /** 3274 * create_target_field_var - Automatically create a variable for a field 3275 * @target_hist_data: The target hist trigger 3276 * @subsys_name: Optional subsystem name 3277 * @event_name: Optional event name 3278 * @var_name: The name of the field (and the resulting variable) 3279 * 3280 * Hist trigger actions fetch data from variables, not directly from 3281 * events. However, for convenience, users are allowed to directly 3282 * specify an event field in an action, which will be automatically 3283 * converted into a variable on their behalf. 3284 * 3285 * This function creates a field variable with the name var_name on 3286 * the hist trigger currently being defined on the target event. If 3287 * subsys_name and event_name are specified, this function simply 3288 * verifies that they do in fact match the target event subsystem and 3289 * event name. 3290 * 3291 * Return: The variable created for the field. 3292 */ 3293 static struct field_var * 3294 create_target_field_var(struct hist_trigger_data *target_hist_data, 3295 char *subsys_name, char *event_name, char *var_name) 3296 { 3297 struct trace_event_file *file = target_hist_data->event_file; 3298 3299 if (subsys_name) { 3300 struct trace_event_call *call; 3301 3302 if (!event_name) 3303 return NULL; 3304 3305 call = file->event_call; 3306 3307 if (strcmp(subsys_name, call->class->system) != 0) 3308 return NULL; 3309 3310 if (strcmp(event_name, trace_event_name(call)) != 0) 3311 return NULL; 3312 } 3313 3314 return create_field_var(target_hist_data, file, var_name); 3315 } 3316 3317 static bool check_track_val_max(u64 track_val, u64 var_val) 3318 { 3319 if (var_val <= track_val) 3320 return false; 3321 3322 return true; 3323 } 3324 3325 static bool check_track_val_changed(u64 track_val, u64 var_val) 3326 { 3327 if (var_val == track_val) 3328 return false; 3329 3330 return true; 3331 } 3332 3333 static u64 get_track_val(struct hist_trigger_data *hist_data, 3334 struct tracing_map_elt *elt, 3335 struct action_data *data) 3336 { 3337 unsigned int track_var_idx = data->track_data.track_var->var.idx; 3338 u64 track_val; 3339 3340 track_val = tracing_map_read_var(elt, track_var_idx); 3341 3342 return track_val; 3343 } 3344 3345 static void save_track_val(struct hist_trigger_data *hist_data, 3346 struct tracing_map_elt *elt, 3347 struct action_data *data, u64 var_val) 3348 { 3349 unsigned int track_var_idx = data->track_data.track_var->var.idx; 3350 3351 tracing_map_set_var(elt, track_var_idx, var_val); 3352 } 3353 3354 static void save_track_data(struct hist_trigger_data *hist_data, 3355 struct tracing_map_elt *elt, 3356 struct trace_buffer *buffer, void *rec, 3357 struct ring_buffer_event *rbe, void *key, 3358 struct action_data *data, u64 *var_ref_vals) 3359 { 3360 if (data->track_data.save_data) 3361 data->track_data.save_data(hist_data, elt, buffer, rec, rbe, 3362 key, data, var_ref_vals); 3363 } 3364 3365 static bool check_track_val(struct tracing_map_elt *elt, 3366 struct action_data *data, 3367 u64 var_val) 3368 { 3369 struct hist_trigger_data *hist_data; 3370 u64 track_val; 3371 3372 hist_data = data->track_data.track_var->hist_data; 3373 track_val = get_track_val(hist_data, elt, data); 3374 3375 return data->track_data.check_val(track_val, var_val); 3376 } 3377 3378 #ifdef CONFIG_TRACER_SNAPSHOT 3379 static bool cond_snapshot_update(struct trace_array *tr, void *cond_data) 3380 { 3381 /* called with tr->max_lock held */ 3382 struct track_data *track_data = tr->cond_snapshot->cond_data; 3383 struct hist_elt_data *elt_data, *track_elt_data; 3384 struct snapshot_context *context = cond_data; 3385 struct action_data *action; 3386 u64 track_val; 3387 3388 if (!track_data) 3389 return false; 3390 3391 action = track_data->action_data; 3392 3393 track_val = get_track_val(track_data->hist_data, context->elt, 3394 track_data->action_data); 3395 3396 if (!action->track_data.check_val(track_data->track_val, track_val)) 3397 return false; 3398 3399 track_data->track_val = track_val; 3400 memcpy(track_data->key, context->key, track_data->key_len); 3401 3402 elt_data = context->elt->private_data; 3403 track_elt_data = track_data->elt.private_data; 3404 if (elt_data->comm) 3405 strscpy(track_elt_data->comm, elt_data->comm, TASK_COMM_LEN); 3406 3407 track_data->updated = true; 3408 3409 return true; 3410 } 3411 3412 static void save_track_data_snapshot(struct hist_trigger_data *hist_data, 3413 struct tracing_map_elt *elt, 3414 struct trace_buffer *buffer, void *rec, 3415 struct ring_buffer_event *rbe, void *key, 3416 struct action_data *data, 3417 u64 *var_ref_vals) 3418 { 3419 struct trace_event_file *file = hist_data->event_file; 3420 struct snapshot_context context; 3421 3422 context.elt = elt; 3423 context.key = key; 3424 3425 tracing_snapshot_cond(file->tr, &context); 3426 } 3427 3428 static void hist_trigger_print_key(struct seq_file *m, 3429 struct hist_trigger_data *hist_data, 3430 void *key, 3431 struct tracing_map_elt *elt); 3432 3433 static struct action_data *snapshot_action(struct hist_trigger_data *hist_data) 3434 { 3435 unsigned int i; 3436 3437 if (!hist_data->n_actions) 3438 return NULL; 3439 3440 for (i = 0; i < hist_data->n_actions; i++) { 3441 struct action_data *data = hist_data->actions[i]; 3442 3443 if (data->action == ACTION_SNAPSHOT) 3444 return data; 3445 } 3446 3447 return NULL; 3448 } 3449 3450 static void track_data_snapshot_print(struct seq_file *m, 3451 struct hist_trigger_data *hist_data) 3452 { 3453 struct trace_event_file *file = hist_data->event_file; 3454 struct track_data *track_data; 3455 struct action_data *action; 3456 3457 track_data = tracing_cond_snapshot_data(file->tr); 3458 if (!track_data) 3459 return; 3460 3461 if (!track_data->updated) 3462 return; 3463 3464 action = snapshot_action(hist_data); 3465 if (!action) 3466 return; 3467 3468 seq_puts(m, "\nSnapshot taken (see tracing/snapshot). Details:\n"); 3469 seq_printf(m, "\ttriggering value { %s(%s) }: %10llu", 3470 action->handler == HANDLER_ONMAX ? "onmax" : "onchange", 3471 action->track_data.var_str, track_data->track_val); 3472 3473 seq_puts(m, "\ttriggered by event with key: "); 3474 hist_trigger_print_key(m, hist_data, track_data->key, &track_data->elt); 3475 seq_putc(m, '\n'); 3476 } 3477 #else 3478 static bool cond_snapshot_update(struct trace_array *tr, void *cond_data) 3479 { 3480 return false; 3481 } 3482 static void save_track_data_snapshot(struct hist_trigger_data *hist_data, 3483 struct tracing_map_elt *elt, 3484 struct trace_buffer *buffer, void *rec, 3485 struct ring_buffer_event *rbe, void *key, 3486 struct action_data *data, 3487 u64 *var_ref_vals) {} 3488 static void track_data_snapshot_print(struct seq_file *m, 3489 struct hist_trigger_data *hist_data) {} 3490 #endif /* CONFIG_TRACER_SNAPSHOT */ 3491 3492 static void track_data_print(struct seq_file *m, 3493 struct hist_trigger_data *hist_data, 3494 struct tracing_map_elt *elt, 3495 struct action_data *data) 3496 { 3497 u64 track_val = get_track_val(hist_data, elt, data); 3498 unsigned int i, save_var_idx; 3499 3500 if (data->handler == HANDLER_ONMAX) 3501 seq_printf(m, "\n\tmax: %10llu", track_val); 3502 else if (data->handler == HANDLER_ONCHANGE) 3503 seq_printf(m, "\n\tchanged: %10llu", track_val); 3504 3505 if (data->action == ACTION_SNAPSHOT) 3506 return; 3507 3508 for (i = 0; i < hist_data->n_save_vars; i++) { 3509 struct hist_field *save_val = hist_data->save_vars[i]->val; 3510 struct hist_field *save_var = hist_data->save_vars[i]->var; 3511 u64 val; 3512 3513 save_var_idx = save_var->var.idx; 3514 3515 val = tracing_map_read_var(elt, save_var_idx); 3516 3517 if (save_val->flags & HIST_FIELD_FL_STRING) { 3518 seq_printf(m, " %s: %-32s", save_var->var.name, 3519 (char *)(uintptr_t)(val)); 3520 } else 3521 seq_printf(m, " %s: %10llu", save_var->var.name, val); 3522 } 3523 } 3524 3525 static void ontrack_action(struct hist_trigger_data *hist_data, 3526 struct tracing_map_elt *elt, 3527 struct trace_buffer *buffer, void *rec, 3528 struct ring_buffer_event *rbe, void *key, 3529 struct action_data *data, u64 *var_ref_vals) 3530 { 3531 u64 var_val = var_ref_vals[data->track_data.var_ref->var_ref_idx]; 3532 3533 if (check_track_val(elt, data, var_val)) { 3534 save_track_val(hist_data, elt, data, var_val); 3535 save_track_data(hist_data, elt, buffer, rec, rbe, 3536 key, data, var_ref_vals); 3537 } 3538 } 3539 3540 static void action_data_destroy(struct action_data *data) 3541 { 3542 unsigned int i; 3543 3544 lockdep_assert_held(&event_mutex); 3545 3546 kfree(data->action_name); 3547 3548 for (i = 0; i < data->n_params; i++) 3549 kfree(data->params[i]); 3550 3551 if (data->synth_event) 3552 data->synth_event->ref--; 3553 3554 kfree(data->synth_event_name); 3555 3556 kfree(data); 3557 } 3558 3559 static void track_data_destroy(struct hist_trigger_data *hist_data, 3560 struct action_data *data) 3561 { 3562 struct trace_event_file *file = hist_data->event_file; 3563 3564 destroy_hist_field(data->track_data.track_var, 0); 3565 3566 if (data->action == ACTION_SNAPSHOT) { 3567 struct track_data *track_data; 3568 3569 track_data = tracing_cond_snapshot_data(file->tr); 3570 if (track_data && track_data->hist_data == hist_data) { 3571 tracing_snapshot_cond_disable(file->tr); 3572 track_data_free(track_data); 3573 } 3574 } 3575 3576 kfree(data->track_data.var_str); 3577 3578 action_data_destroy(data); 3579 } 3580 3581 static int action_create(struct hist_trigger_data *hist_data, 3582 struct action_data *data); 3583 3584 static int track_data_create(struct hist_trigger_data *hist_data, 3585 struct action_data *data) 3586 { 3587 struct hist_field *var_field, *ref_field, *track_var = NULL; 3588 struct trace_event_file *file = hist_data->event_file; 3589 struct trace_array *tr = file->tr; 3590 char *track_data_var_str; 3591 int ret = 0; 3592 3593 track_data_var_str = data->track_data.var_str; 3594 if (track_data_var_str[0] != '$') { 3595 hist_err(tr, HIST_ERR_ONX_NOT_VAR, errpos(track_data_var_str)); 3596 return -EINVAL; 3597 } 3598 track_data_var_str++; 3599 3600 var_field = find_target_event_var(hist_data, NULL, NULL, track_data_var_str); 3601 if (!var_field) { 3602 hist_err(tr, HIST_ERR_ONX_VAR_NOT_FOUND, errpos(track_data_var_str)); 3603 return -EINVAL; 3604 } 3605 3606 ref_field = create_var_ref(hist_data, var_field, NULL, NULL); 3607 if (!ref_field) 3608 return -ENOMEM; 3609 3610 data->track_data.var_ref = ref_field; 3611 3612 if (data->handler == HANDLER_ONMAX) 3613 track_var = create_var(hist_data, file, "__max", sizeof(u64), "u64"); 3614 if (IS_ERR(track_var)) { 3615 hist_err(tr, HIST_ERR_ONX_VAR_CREATE_FAIL, 0); 3616 ret = PTR_ERR(track_var); 3617 goto out; 3618 } 3619 3620 if (data->handler == HANDLER_ONCHANGE) 3621 track_var = create_var(hist_data, file, "__change", sizeof(u64), "u64"); 3622 if (IS_ERR(track_var)) { 3623 hist_err(tr, HIST_ERR_ONX_VAR_CREATE_FAIL, 0); 3624 ret = PTR_ERR(track_var); 3625 goto out; 3626 } 3627 data->track_data.track_var = track_var; 3628 3629 ret = action_create(hist_data, data); 3630 out: 3631 return ret; 3632 } 3633 3634 static int parse_action_params(struct trace_array *tr, char *params, 3635 struct action_data *data) 3636 { 3637 char *param, *saved_param; 3638 bool first_param = true; 3639 int ret = 0; 3640 3641 while (params) { 3642 if (data->n_params >= SYNTH_FIELDS_MAX) { 3643 hist_err(tr, HIST_ERR_TOO_MANY_PARAMS, 0); 3644 ret = -EINVAL; 3645 goto out; 3646 } 3647 3648 param = strsep(¶ms, ","); 3649 if (!param) { 3650 hist_err(tr, HIST_ERR_PARAM_NOT_FOUND, 0); 3651 ret = -EINVAL; 3652 goto out; 3653 } 3654 3655 param = strstrip(param); 3656 if (strlen(param) < 2) { 3657 hist_err(tr, HIST_ERR_INVALID_PARAM, errpos(param)); 3658 ret = -EINVAL; 3659 goto out; 3660 } 3661 3662 saved_param = kstrdup(param, GFP_KERNEL); 3663 if (!saved_param) { 3664 ret = -ENOMEM; 3665 goto out; 3666 } 3667 3668 if (first_param && data->use_trace_keyword) { 3669 data->synth_event_name = saved_param; 3670 first_param = false; 3671 continue; 3672 } 3673 first_param = false; 3674 3675 data->params[data->n_params++] = saved_param; 3676 } 3677 out: 3678 return ret; 3679 } 3680 3681 static int action_parse(struct trace_array *tr, char *str, struct action_data *data, 3682 enum handler_id handler) 3683 { 3684 char *action_name; 3685 int ret = 0; 3686 3687 strsep(&str, "."); 3688 if (!str) { 3689 hist_err(tr, HIST_ERR_ACTION_NOT_FOUND, 0); 3690 ret = -EINVAL; 3691 goto out; 3692 } 3693 3694 action_name = strsep(&str, "("); 3695 if (!action_name || !str) { 3696 hist_err(tr, HIST_ERR_ACTION_NOT_FOUND, 0); 3697 ret = -EINVAL; 3698 goto out; 3699 } 3700 3701 if (str_has_prefix(action_name, "save")) { 3702 char *params = strsep(&str, ")"); 3703 3704 if (!params) { 3705 hist_err(tr, HIST_ERR_NO_SAVE_PARAMS, 0); 3706 ret = -EINVAL; 3707 goto out; 3708 } 3709 3710 ret = parse_action_params(tr, params, data); 3711 if (ret) 3712 goto out; 3713 3714 if (handler == HANDLER_ONMAX) 3715 data->track_data.check_val = check_track_val_max; 3716 else if (handler == HANDLER_ONCHANGE) 3717 data->track_data.check_val = check_track_val_changed; 3718 else { 3719 hist_err(tr, HIST_ERR_ACTION_MISMATCH, errpos(action_name)); 3720 ret = -EINVAL; 3721 goto out; 3722 } 3723 3724 data->track_data.save_data = save_track_data_vars; 3725 data->fn = ontrack_action; 3726 data->action = ACTION_SAVE; 3727 } else if (str_has_prefix(action_name, "snapshot")) { 3728 char *params = strsep(&str, ")"); 3729 3730 if (!str) { 3731 hist_err(tr, HIST_ERR_NO_CLOSING_PAREN, errpos(params)); 3732 ret = -EINVAL; 3733 goto out; 3734 } 3735 3736 if (handler == HANDLER_ONMAX) 3737 data->track_data.check_val = check_track_val_max; 3738 else if (handler == HANDLER_ONCHANGE) 3739 data->track_data.check_val = check_track_val_changed; 3740 else { 3741 hist_err(tr, HIST_ERR_ACTION_MISMATCH, errpos(action_name)); 3742 ret = -EINVAL; 3743 goto out; 3744 } 3745 3746 data->track_data.save_data = save_track_data_snapshot; 3747 data->fn = ontrack_action; 3748 data->action = ACTION_SNAPSHOT; 3749 } else { 3750 char *params = strsep(&str, ")"); 3751 3752 if (str_has_prefix(action_name, "trace")) 3753 data->use_trace_keyword = true; 3754 3755 if (params) { 3756 ret = parse_action_params(tr, params, data); 3757 if (ret) 3758 goto out; 3759 } 3760 3761 if (handler == HANDLER_ONMAX) 3762 data->track_data.check_val = check_track_val_max; 3763 else if (handler == HANDLER_ONCHANGE) 3764 data->track_data.check_val = check_track_val_changed; 3765 3766 if (handler != HANDLER_ONMATCH) { 3767 data->track_data.save_data = action_trace; 3768 data->fn = ontrack_action; 3769 } else 3770 data->fn = action_trace; 3771 3772 data->action = ACTION_TRACE; 3773 } 3774 3775 data->action_name = kstrdup(action_name, GFP_KERNEL); 3776 if (!data->action_name) { 3777 ret = -ENOMEM; 3778 goto out; 3779 } 3780 3781 data->handler = handler; 3782 out: 3783 return ret; 3784 } 3785 3786 static struct action_data *track_data_parse(struct hist_trigger_data *hist_data, 3787 char *str, enum handler_id handler) 3788 { 3789 struct action_data *data; 3790 int ret = -EINVAL; 3791 char *var_str; 3792 3793 data = kzalloc(sizeof(*data), GFP_KERNEL); 3794 if (!data) 3795 return ERR_PTR(-ENOMEM); 3796 3797 var_str = strsep(&str, ")"); 3798 if (!var_str || !str) { 3799 ret = -EINVAL; 3800 goto free; 3801 } 3802 3803 data->track_data.var_str = kstrdup(var_str, GFP_KERNEL); 3804 if (!data->track_data.var_str) { 3805 ret = -ENOMEM; 3806 goto free; 3807 } 3808 3809 ret = action_parse(hist_data->event_file->tr, str, data, handler); 3810 if (ret) 3811 goto free; 3812 out: 3813 return data; 3814 free: 3815 track_data_destroy(hist_data, data); 3816 data = ERR_PTR(ret); 3817 goto out; 3818 } 3819 3820 static void onmatch_destroy(struct action_data *data) 3821 { 3822 kfree(data->match_data.event); 3823 kfree(data->match_data.event_system); 3824 3825 action_data_destroy(data); 3826 } 3827 3828 static void destroy_field_var(struct field_var *field_var) 3829 { 3830 if (!field_var) 3831 return; 3832 3833 destroy_hist_field(field_var->var, 0); 3834 destroy_hist_field(field_var->val, 0); 3835 3836 kfree(field_var); 3837 } 3838 3839 static void destroy_field_vars(struct hist_trigger_data *hist_data) 3840 { 3841 unsigned int i; 3842 3843 for (i = 0; i < hist_data->n_field_vars; i++) 3844 destroy_field_var(hist_data->field_vars[i]); 3845 3846 for (i = 0; i < hist_data->n_save_vars; i++) 3847 destroy_field_var(hist_data->save_vars[i]); 3848 } 3849 3850 static void save_field_var(struct hist_trigger_data *hist_data, 3851 struct field_var *field_var) 3852 { 3853 hist_data->field_vars[hist_data->n_field_vars++] = field_var; 3854 3855 /* Stack traces are saved in the string storage too */ 3856 if (field_var->val->flags & (HIST_FIELD_FL_STRING | HIST_FIELD_FL_STACKTRACE)) 3857 hist_data->n_field_var_str++; 3858 } 3859 3860 3861 static int check_synth_field(struct synth_event *event, 3862 struct hist_field *hist_field, 3863 unsigned int field_pos) 3864 { 3865 struct synth_field *field; 3866 3867 if (field_pos >= event->n_fields) 3868 return -EINVAL; 3869 3870 field = event->fields[field_pos]; 3871 3872 /* 3873 * A dynamic string synth field can accept static or 3874 * dynamic. A static string synth field can only accept a 3875 * same-sized static string, which is checked for later. 3876 */ 3877 if (strstr(hist_field->type, "char[") && field->is_string 3878 && field->is_dynamic) 3879 return 0; 3880 3881 if (strstr(hist_field->type, "long[") && field->is_stack) 3882 return 0; 3883 3884 if (strcmp(field->type, hist_field->type) != 0) { 3885 if (field->size != hist_field->size || 3886 (!field->is_string && field->is_signed != hist_field->is_signed)) 3887 return -EINVAL; 3888 } 3889 3890 return 0; 3891 } 3892 3893 static struct hist_field * 3894 trace_action_find_var(struct hist_trigger_data *hist_data, 3895 struct action_data *data, 3896 char *system, char *event, char *var) 3897 { 3898 struct trace_array *tr = hist_data->event_file->tr; 3899 struct hist_field *hist_field; 3900 3901 var++; /* skip '$' */ 3902 3903 hist_field = find_target_event_var(hist_data, system, event, var); 3904 if (!hist_field) { 3905 if (!system && data->handler == HANDLER_ONMATCH) { 3906 system = data->match_data.event_system; 3907 event = data->match_data.event; 3908 } 3909 3910 hist_field = find_event_var(hist_data, system, event, var); 3911 } 3912 3913 if (!hist_field) 3914 hist_err(tr, HIST_ERR_PARAM_NOT_FOUND, errpos(var)); 3915 3916 return hist_field; 3917 } 3918 3919 static struct hist_field * 3920 trace_action_create_field_var(struct hist_trigger_data *hist_data, 3921 struct action_data *data, char *system, 3922 char *event, char *var) 3923 { 3924 struct hist_field *hist_field = NULL; 3925 struct field_var *field_var; 3926 3927 /* 3928 * First try to create a field var on the target event (the 3929 * currently being defined). This will create a variable for 3930 * unqualified fields on the target event, or if qualified, 3931 * target fields that have qualified names matching the target. 3932 */ 3933 field_var = create_target_field_var(hist_data, system, event, var); 3934 3935 if (field_var && !IS_ERR(field_var)) { 3936 save_field_var(hist_data, field_var); 3937 hist_field = field_var->var; 3938 } else { 3939 field_var = NULL; 3940 /* 3941 * If no explicit system.event is specified, default to 3942 * looking for fields on the onmatch(system.event.xxx) 3943 * event. 3944 */ 3945 if (!system && data->handler == HANDLER_ONMATCH) { 3946 system = data->match_data.event_system; 3947 event = data->match_data.event; 3948 } 3949 3950 if (!event) 3951 goto free; 3952 /* 3953 * At this point, we're looking at a field on another 3954 * event. Because we can't modify a hist trigger on 3955 * another event to add a variable for a field, we need 3956 * to create a new trigger on that event and create the 3957 * variable at the same time. 3958 */ 3959 hist_field = create_field_var_hist(hist_data, system, event, var); 3960 if (IS_ERR(hist_field)) 3961 goto free; 3962 } 3963 out: 3964 return hist_field; 3965 free: 3966 destroy_field_var(field_var); 3967 hist_field = NULL; 3968 goto out; 3969 } 3970 3971 static int trace_action_create(struct hist_trigger_data *hist_data, 3972 struct action_data *data) 3973 { 3974 struct trace_array *tr = hist_data->event_file->tr; 3975 char *event_name, *param, *system = NULL; 3976 struct hist_field *hist_field, *var_ref; 3977 unsigned int i; 3978 unsigned int field_pos = 0; 3979 struct synth_event *event; 3980 char *synth_event_name; 3981 int var_ref_idx, ret = 0; 3982 3983 lockdep_assert_held(&event_mutex); 3984 3985 /* Sanity check to avoid out-of-bound write on 'data->var_ref_idx' */ 3986 if (data->n_params > SYNTH_FIELDS_MAX) 3987 return -EINVAL; 3988 3989 if (data->use_trace_keyword) 3990 synth_event_name = data->synth_event_name; 3991 else 3992 synth_event_name = data->action_name; 3993 3994 event = find_synth_event(synth_event_name); 3995 if (!event) { 3996 hist_err(tr, HIST_ERR_SYNTH_EVENT_NOT_FOUND, errpos(synth_event_name)); 3997 return -EINVAL; 3998 } 3999 4000 event->ref++; 4001 4002 for (i = 0; i < data->n_params; i++) { 4003 char *p; 4004 4005 p = param = kstrdup(data->params[i], GFP_KERNEL); 4006 if (!param) { 4007 ret = -ENOMEM; 4008 goto err; 4009 } 4010 4011 system = strsep(¶m, "."); 4012 if (!param) { 4013 param = (char *)system; 4014 system = event_name = NULL; 4015 } else { 4016 event_name = strsep(¶m, "."); 4017 if (!param) { 4018 kfree(p); 4019 ret = -EINVAL; 4020 goto err; 4021 } 4022 } 4023 4024 if (param[0] == '$') 4025 hist_field = trace_action_find_var(hist_data, data, 4026 system, event_name, 4027 param); 4028 else 4029 hist_field = trace_action_create_field_var(hist_data, 4030 data, 4031 system, 4032 event_name, 4033 param); 4034 4035 if (!hist_field) { 4036 kfree(p); 4037 ret = -EINVAL; 4038 goto err; 4039 } 4040 4041 if (check_synth_field(event, hist_field, field_pos) == 0) { 4042 var_ref = create_var_ref(hist_data, hist_field, 4043 system, event_name); 4044 if (!var_ref) { 4045 kfree(p); 4046 ret = -ENOMEM; 4047 goto err; 4048 } 4049 4050 var_ref_idx = find_var_ref_idx(hist_data, var_ref); 4051 if (WARN_ON(var_ref_idx < 0)) { 4052 kfree(p); 4053 ret = var_ref_idx; 4054 goto err; 4055 } 4056 4057 data->var_ref_idx[i] = var_ref_idx; 4058 4059 field_pos++; 4060 kfree(p); 4061 continue; 4062 } 4063 4064 hist_err(tr, HIST_ERR_SYNTH_TYPE_MISMATCH, errpos(param)); 4065 kfree(p); 4066 ret = -EINVAL; 4067 goto err; 4068 } 4069 4070 if (field_pos != event->n_fields) { 4071 hist_err(tr, HIST_ERR_SYNTH_COUNT_MISMATCH, errpos(event->name)); 4072 ret = -EINVAL; 4073 goto err; 4074 } 4075 4076 data->synth_event = event; 4077 out: 4078 return ret; 4079 err: 4080 event->ref--; 4081 4082 goto out; 4083 } 4084 4085 static int action_create(struct hist_trigger_data *hist_data, 4086 struct action_data *data) 4087 { 4088 struct trace_event_file *file = hist_data->event_file; 4089 struct trace_array *tr = file->tr; 4090 struct track_data *track_data; 4091 struct field_var *field_var; 4092 unsigned int i; 4093 char *param; 4094 int ret = 0; 4095 4096 if (data->action == ACTION_TRACE) 4097 return trace_action_create(hist_data, data); 4098 4099 if (data->action == ACTION_SNAPSHOT) { 4100 track_data = track_data_alloc(hist_data->key_size, data, hist_data); 4101 if (IS_ERR(track_data)) { 4102 ret = PTR_ERR(track_data); 4103 goto out; 4104 } 4105 4106 ret = tracing_snapshot_cond_enable(file->tr, track_data, 4107 cond_snapshot_update); 4108 if (ret) 4109 track_data_free(track_data); 4110 4111 goto out; 4112 } 4113 4114 if (data->action == ACTION_SAVE) { 4115 if (hist_data->n_save_vars) { 4116 ret = -EEXIST; 4117 hist_err(tr, HIST_ERR_TOO_MANY_SAVE_ACTIONS, 0); 4118 goto out; 4119 } 4120 4121 for (i = 0; i < data->n_params; i++) { 4122 param = kstrdup(data->params[i], GFP_KERNEL); 4123 if (!param) { 4124 ret = -ENOMEM; 4125 goto out; 4126 } 4127 4128 field_var = create_target_field_var(hist_data, NULL, NULL, param); 4129 if (IS_ERR(field_var)) { 4130 hist_err(tr, HIST_ERR_FIELD_VAR_CREATE_FAIL, 4131 errpos(param)); 4132 ret = PTR_ERR(field_var); 4133 kfree(param); 4134 goto out; 4135 } 4136 4137 hist_data->save_vars[hist_data->n_save_vars++] = field_var; 4138 if (field_var->val->flags & 4139 (HIST_FIELD_FL_STRING | HIST_FIELD_FL_STACKTRACE)) 4140 hist_data->n_save_var_str++; 4141 kfree(param); 4142 } 4143 } 4144 out: 4145 return ret; 4146 } 4147 4148 static int onmatch_create(struct hist_trigger_data *hist_data, 4149 struct action_data *data) 4150 { 4151 return action_create(hist_data, data); 4152 } 4153 4154 static struct action_data *onmatch_parse(struct trace_array *tr, char *str) 4155 { 4156 char *match_event, *match_event_system; 4157 struct action_data *data; 4158 int ret = -EINVAL; 4159 4160 data = kzalloc(sizeof(*data), GFP_KERNEL); 4161 if (!data) 4162 return ERR_PTR(-ENOMEM); 4163 4164 match_event = strsep(&str, ")"); 4165 if (!match_event || !str) { 4166 hist_err(tr, HIST_ERR_NO_CLOSING_PAREN, errpos(match_event)); 4167 goto free; 4168 } 4169 4170 match_event_system = strsep(&match_event, "."); 4171 if (!match_event) { 4172 hist_err(tr, HIST_ERR_SUBSYS_NOT_FOUND, errpos(match_event_system)); 4173 goto free; 4174 } 4175 4176 if (IS_ERR(event_file(tr, match_event_system, match_event))) { 4177 hist_err(tr, HIST_ERR_INVALID_SUBSYS_EVENT, errpos(match_event)); 4178 goto free; 4179 } 4180 4181 data->match_data.event = kstrdup(match_event, GFP_KERNEL); 4182 if (!data->match_data.event) { 4183 ret = -ENOMEM; 4184 goto free; 4185 } 4186 4187 data->match_data.event_system = kstrdup(match_event_system, GFP_KERNEL); 4188 if (!data->match_data.event_system) { 4189 ret = -ENOMEM; 4190 goto free; 4191 } 4192 4193 ret = action_parse(tr, str, data, HANDLER_ONMATCH); 4194 if (ret) 4195 goto free; 4196 out: 4197 return data; 4198 free: 4199 onmatch_destroy(data); 4200 data = ERR_PTR(ret); 4201 goto out; 4202 } 4203 4204 static int create_hitcount_val(struct hist_trigger_data *hist_data) 4205 { 4206 hist_data->fields[HITCOUNT_IDX] = 4207 create_hist_field(hist_data, NULL, HIST_FIELD_FL_HITCOUNT, NULL); 4208 if (!hist_data->fields[HITCOUNT_IDX]) 4209 return -ENOMEM; 4210 4211 hist_data->n_vals++; 4212 hist_data->n_fields++; 4213 4214 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX)) 4215 return -EINVAL; 4216 4217 return 0; 4218 } 4219 4220 static int __create_val_field(struct hist_trigger_data *hist_data, 4221 unsigned int val_idx, 4222 struct trace_event_file *file, 4223 char *var_name, char *field_str, 4224 unsigned long flags) 4225 { 4226 struct hist_field *hist_field; 4227 int ret = 0, n_subexprs = 0; 4228 4229 hist_field = parse_expr(hist_data, file, field_str, flags, var_name, &n_subexprs); 4230 if (IS_ERR(hist_field)) { 4231 ret = PTR_ERR(hist_field); 4232 goto out; 4233 } 4234 4235 /* values and variables should not have some modifiers */ 4236 if (hist_field->flags & HIST_FIELD_FL_VAR) { 4237 /* Variable */ 4238 if (hist_field->flags & (HIST_FIELD_FL_GRAPH | HIST_FIELD_FL_PERCENT | 4239 HIST_FIELD_FL_BUCKET | HIST_FIELD_FL_LOG2)) 4240 goto err; 4241 } else { 4242 /* Value */ 4243 if (hist_field->flags & (HIST_FIELD_FL_GRAPH | HIST_FIELD_FL_PERCENT | 4244 HIST_FIELD_FL_BUCKET | HIST_FIELD_FL_LOG2 | 4245 HIST_FIELD_FL_SYM | HIST_FIELD_FL_SYM_OFFSET | 4246 HIST_FIELD_FL_SYSCALL | HIST_FIELD_FL_STACKTRACE)) 4247 goto err; 4248 } 4249 4250 hist_data->fields[val_idx] = hist_field; 4251 4252 ++hist_data->n_vals; 4253 ++hist_data->n_fields; 4254 4255 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX)) 4256 ret = -EINVAL; 4257 out: 4258 return ret; 4259 err: 4260 hist_err(file->tr, HIST_ERR_BAD_FIELD_MODIFIER, errpos(field_str)); 4261 return -EINVAL; 4262 } 4263 4264 static int create_val_field(struct hist_trigger_data *hist_data, 4265 unsigned int val_idx, 4266 struct trace_event_file *file, 4267 char *field_str) 4268 { 4269 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX)) 4270 return -EINVAL; 4271 4272 return __create_val_field(hist_data, val_idx, file, NULL, field_str, 0); 4273 } 4274 4275 static const char no_comm[] = "(no comm)"; 4276 4277 static u64 hist_field_execname(struct hist_field *hist_field, 4278 struct tracing_map_elt *elt, 4279 struct trace_buffer *buffer, 4280 struct ring_buffer_event *rbe, 4281 void *event) 4282 { 4283 struct hist_elt_data *elt_data; 4284 4285 if (WARN_ON_ONCE(!elt)) 4286 return (u64)(unsigned long)no_comm; 4287 4288 elt_data = elt->private_data; 4289 4290 if (WARN_ON_ONCE(!elt_data->comm)) 4291 return (u64)(unsigned long)no_comm; 4292 4293 return (u64)(unsigned long)(elt_data->comm); 4294 } 4295 4296 static u64 hist_field_stack(struct hist_field *hist_field, 4297 struct tracing_map_elt *elt, 4298 struct trace_buffer *buffer, 4299 struct ring_buffer_event *rbe, 4300 void *event) 4301 { 4302 u32 str_item = *(u32 *)(event + hist_field->field->offset); 4303 int str_loc = str_item & 0xffff; 4304 char *addr = (char *)(event + str_loc); 4305 4306 return (u64)(unsigned long)addr; 4307 } 4308 4309 static u64 hist_fn_call(struct hist_field *hist_field, 4310 struct tracing_map_elt *elt, 4311 struct trace_buffer *buffer, 4312 struct ring_buffer_event *rbe, 4313 void *event) 4314 { 4315 switch (hist_field->fn_num) { 4316 case HIST_FIELD_FN_VAR_REF: 4317 return hist_field_var_ref(hist_field, elt, buffer, rbe, event); 4318 case HIST_FIELD_FN_COUNTER: 4319 return hist_field_counter(hist_field, elt, buffer, rbe, event); 4320 case HIST_FIELD_FN_CONST: 4321 return hist_field_const(hist_field, elt, buffer, rbe, event); 4322 case HIST_FIELD_FN_LOG2: 4323 return hist_field_log2(hist_field, elt, buffer, rbe, event); 4324 case HIST_FIELD_FN_BUCKET: 4325 return hist_field_bucket(hist_field, elt, buffer, rbe, event); 4326 case HIST_FIELD_FN_TIMESTAMP: 4327 return hist_field_timestamp(hist_field, elt, buffer, rbe, event); 4328 case HIST_FIELD_FN_CPU: 4329 return hist_field_cpu(hist_field, elt, buffer, rbe, event); 4330 case HIST_FIELD_FN_STRING: 4331 return hist_field_string(hist_field, elt, buffer, rbe, event); 4332 case HIST_FIELD_FN_DYNSTRING: 4333 return hist_field_dynstring(hist_field, elt, buffer, rbe, event); 4334 case HIST_FIELD_FN_RELDYNSTRING: 4335 return hist_field_reldynstring(hist_field, elt, buffer, rbe, event); 4336 case HIST_FIELD_FN_PSTRING: 4337 return hist_field_pstring(hist_field, elt, buffer, rbe, event); 4338 case HIST_FIELD_FN_S64: 4339 return hist_field_s64(hist_field, elt, buffer, rbe, event); 4340 case HIST_FIELD_FN_U64: 4341 return hist_field_u64(hist_field, elt, buffer, rbe, event); 4342 case HIST_FIELD_FN_S32: 4343 return hist_field_s32(hist_field, elt, buffer, rbe, event); 4344 case HIST_FIELD_FN_U32: 4345 return hist_field_u32(hist_field, elt, buffer, rbe, event); 4346 case HIST_FIELD_FN_S16: 4347 return hist_field_s16(hist_field, elt, buffer, rbe, event); 4348 case HIST_FIELD_FN_U16: 4349 return hist_field_u16(hist_field, elt, buffer, rbe, event); 4350 case HIST_FIELD_FN_S8: 4351 return hist_field_s8(hist_field, elt, buffer, rbe, event); 4352 case HIST_FIELD_FN_U8: 4353 return hist_field_u8(hist_field, elt, buffer, rbe, event); 4354 case HIST_FIELD_FN_UMINUS: 4355 return hist_field_unary_minus(hist_field, elt, buffer, rbe, event); 4356 case HIST_FIELD_FN_MINUS: 4357 return hist_field_minus(hist_field, elt, buffer, rbe, event); 4358 case HIST_FIELD_FN_PLUS: 4359 return hist_field_plus(hist_field, elt, buffer, rbe, event); 4360 case HIST_FIELD_FN_DIV: 4361 return hist_field_div(hist_field, elt, buffer, rbe, event); 4362 case HIST_FIELD_FN_MULT: 4363 return hist_field_mult(hist_field, elt, buffer, rbe, event); 4364 case HIST_FIELD_FN_DIV_POWER2: 4365 return div_by_power_of_two(hist_field, elt, buffer, rbe, event); 4366 case HIST_FIELD_FN_DIV_NOT_POWER2: 4367 return div_by_not_power_of_two(hist_field, elt, buffer, rbe, event); 4368 case HIST_FIELD_FN_DIV_MULT_SHIFT: 4369 return div_by_mult_and_shift(hist_field, elt, buffer, rbe, event); 4370 case HIST_FIELD_FN_EXECNAME: 4371 return hist_field_execname(hist_field, elt, buffer, rbe, event); 4372 case HIST_FIELD_FN_STACK: 4373 return hist_field_stack(hist_field, elt, buffer, rbe, event); 4374 default: 4375 return 0; 4376 } 4377 } 4378 4379 /* Convert a var that points to common_pid.execname to a string */ 4380 static void update_var_execname(struct hist_field *hist_field) 4381 { 4382 hist_field->flags = HIST_FIELD_FL_STRING | HIST_FIELD_FL_VAR | 4383 HIST_FIELD_FL_EXECNAME; 4384 hist_field->size = MAX_FILTER_STR_VAL; 4385 hist_field->is_signed = 0; 4386 4387 kfree_const(hist_field->type); 4388 hist_field->type = "char[]"; 4389 4390 hist_field->fn_num = HIST_FIELD_FN_EXECNAME; 4391 } 4392 4393 static int create_var_field(struct hist_trigger_data *hist_data, 4394 unsigned int val_idx, 4395 struct trace_event_file *file, 4396 char *var_name, char *expr_str) 4397 { 4398 struct trace_array *tr = hist_data->event_file->tr; 4399 unsigned long flags = 0; 4400 int ret; 4401 4402 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX)) 4403 return -EINVAL; 4404 4405 if (find_var(hist_data, file, var_name) && !hist_data->remove) { 4406 hist_err(tr, HIST_ERR_DUPLICATE_VAR, errpos(var_name)); 4407 return -EINVAL; 4408 } 4409 4410 flags |= HIST_FIELD_FL_VAR; 4411 hist_data->n_vars++; 4412 if (WARN_ON(hist_data->n_vars > TRACING_MAP_VARS_MAX)) 4413 return -EINVAL; 4414 4415 ret = __create_val_field(hist_data, val_idx, file, var_name, expr_str, flags); 4416 4417 if (!ret && hist_data->fields[val_idx]->flags & HIST_FIELD_FL_EXECNAME) 4418 update_var_execname(hist_data->fields[val_idx]); 4419 4420 if (!ret && hist_data->fields[val_idx]->flags & 4421 (HIST_FIELD_FL_STRING | HIST_FIELD_FL_STACKTRACE)) 4422 hist_data->fields[val_idx]->var_str_idx = hist_data->n_var_str++; 4423 4424 return ret; 4425 } 4426 4427 static int create_val_fields(struct hist_trigger_data *hist_data, 4428 struct trace_event_file *file) 4429 { 4430 unsigned int i, j = 1, n_hitcount = 0; 4431 char *fields_str, *field_str; 4432 int ret; 4433 4434 ret = create_hitcount_val(hist_data); 4435 if (ret) 4436 goto out; 4437 4438 fields_str = hist_data->attrs->vals_str; 4439 if (!fields_str) 4440 goto out; 4441 4442 for (i = 0, j = 1; i < TRACING_MAP_VALS_MAX && 4443 j < TRACING_MAP_VALS_MAX; i++) { 4444 field_str = strsep(&fields_str, ","); 4445 if (!field_str) 4446 break; 4447 4448 if (strcmp(field_str, "hitcount") == 0) { 4449 if (!n_hitcount++) 4450 continue; 4451 } 4452 4453 ret = create_val_field(hist_data, j++, file, field_str); 4454 if (ret) 4455 goto out; 4456 } 4457 4458 if (fields_str && (strcmp(fields_str, "hitcount") != 0)) 4459 ret = -EINVAL; 4460 out: 4461 /* There is only raw hitcount but nohitcount suppresses it. */ 4462 if (j == 1 && hist_data->attrs->no_hitcount) { 4463 hist_err(hist_data->event_file->tr, HIST_ERR_NEED_NOHC_VAL, 0); 4464 ret = -ENOENT; 4465 } 4466 4467 return ret; 4468 } 4469 4470 static int create_key_field(struct hist_trigger_data *hist_data, 4471 unsigned int key_idx, 4472 unsigned int key_offset, 4473 struct trace_event_file *file, 4474 char *field_str) 4475 { 4476 struct trace_array *tr = hist_data->event_file->tr; 4477 struct hist_field *hist_field = NULL; 4478 unsigned long flags = 0; 4479 unsigned int key_size; 4480 int ret = 0, n_subexprs = 0; 4481 4482 if (WARN_ON(key_idx >= HIST_FIELDS_MAX)) 4483 return -EINVAL; 4484 4485 flags |= HIST_FIELD_FL_KEY; 4486 4487 if (strcmp(field_str, "stacktrace") == 0) { 4488 flags |= HIST_FIELD_FL_STACKTRACE; 4489 key_size = sizeof(unsigned long) * HIST_STACKTRACE_DEPTH; 4490 hist_field = create_hist_field(hist_data, NULL, flags, NULL); 4491 } else { 4492 hist_field = parse_expr(hist_data, file, field_str, flags, 4493 NULL, &n_subexprs); 4494 if (IS_ERR(hist_field)) { 4495 ret = PTR_ERR(hist_field); 4496 goto out; 4497 } 4498 4499 if (field_has_hist_vars(hist_field, 0)) { 4500 hist_err(tr, HIST_ERR_INVALID_REF_KEY, errpos(field_str)); 4501 destroy_hist_field(hist_field, 0); 4502 ret = -EINVAL; 4503 goto out; 4504 } 4505 4506 key_size = hist_field->size; 4507 } 4508 4509 hist_data->fields[key_idx] = hist_field; 4510 4511 key_size = ALIGN(key_size, sizeof(u64)); 4512 hist_data->fields[key_idx]->size = key_size; 4513 hist_data->fields[key_idx]->offset = key_offset; 4514 4515 hist_data->key_size += key_size; 4516 4517 if (hist_data->key_size > HIST_KEY_SIZE_MAX) { 4518 ret = -EINVAL; 4519 goto out; 4520 } 4521 4522 hist_data->n_keys++; 4523 hist_data->n_fields++; 4524 4525 if (WARN_ON(hist_data->n_keys > TRACING_MAP_KEYS_MAX)) 4526 return -EINVAL; 4527 4528 ret = key_size; 4529 out: 4530 return ret; 4531 } 4532 4533 static int create_key_fields(struct hist_trigger_data *hist_data, 4534 struct trace_event_file *file) 4535 { 4536 unsigned int i, key_offset = 0, n_vals = hist_data->n_vals; 4537 char *fields_str, *field_str; 4538 int ret = -EINVAL; 4539 4540 fields_str = hist_data->attrs->keys_str; 4541 if (!fields_str) 4542 goto out; 4543 4544 for (i = n_vals; i < n_vals + TRACING_MAP_KEYS_MAX; i++) { 4545 field_str = strsep(&fields_str, ","); 4546 if (!field_str) 4547 break; 4548 ret = create_key_field(hist_data, i, key_offset, 4549 file, field_str); 4550 if (ret < 0) 4551 goto out; 4552 key_offset += ret; 4553 } 4554 if (fields_str) { 4555 ret = -EINVAL; 4556 goto out; 4557 } 4558 ret = 0; 4559 out: 4560 return ret; 4561 } 4562 4563 static int create_var_fields(struct hist_trigger_data *hist_data, 4564 struct trace_event_file *file) 4565 { 4566 unsigned int i, j = hist_data->n_vals; 4567 int ret = 0; 4568 4569 unsigned int n_vars = hist_data->attrs->var_defs.n_vars; 4570 4571 for (i = 0; i < n_vars; i++) { 4572 char *var_name = hist_data->attrs->var_defs.name[i]; 4573 char *expr = hist_data->attrs->var_defs.expr[i]; 4574 4575 ret = create_var_field(hist_data, j++, file, var_name, expr); 4576 if (ret) 4577 goto out; 4578 } 4579 out: 4580 return ret; 4581 } 4582 4583 static void free_var_defs(struct hist_trigger_data *hist_data) 4584 { 4585 unsigned int i; 4586 4587 for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) { 4588 kfree(hist_data->attrs->var_defs.name[i]); 4589 kfree(hist_data->attrs->var_defs.expr[i]); 4590 } 4591 4592 hist_data->attrs->var_defs.n_vars = 0; 4593 } 4594 4595 static int parse_var_defs(struct hist_trigger_data *hist_data) 4596 { 4597 struct trace_array *tr = hist_data->event_file->tr; 4598 char *s, *str, *var_name, *field_str; 4599 unsigned int i, j, n_vars = 0; 4600 int ret = 0; 4601 4602 for (i = 0; i < hist_data->attrs->n_assignments; i++) { 4603 str = hist_data->attrs->assignment_str[i]; 4604 for (j = 0; j < TRACING_MAP_VARS_MAX; j++) { 4605 field_str = strsep(&str, ","); 4606 if (!field_str) 4607 break; 4608 4609 var_name = strsep(&field_str, "="); 4610 if (!var_name || !field_str) { 4611 hist_err(tr, HIST_ERR_MALFORMED_ASSIGNMENT, 4612 errpos(var_name)); 4613 ret = -EINVAL; 4614 goto free; 4615 } 4616 4617 if (n_vars == TRACING_MAP_VARS_MAX) { 4618 hist_err(tr, HIST_ERR_TOO_MANY_VARS, errpos(var_name)); 4619 ret = -EINVAL; 4620 goto free; 4621 } 4622 4623 s = kstrdup(var_name, GFP_KERNEL); 4624 if (!s) { 4625 ret = -ENOMEM; 4626 goto free; 4627 } 4628 hist_data->attrs->var_defs.name[n_vars] = s; 4629 4630 s = kstrdup(field_str, GFP_KERNEL); 4631 if (!s) { 4632 kfree(hist_data->attrs->var_defs.name[n_vars]); 4633 hist_data->attrs->var_defs.name[n_vars] = NULL; 4634 ret = -ENOMEM; 4635 goto free; 4636 } 4637 hist_data->attrs->var_defs.expr[n_vars++] = s; 4638 4639 hist_data->attrs->var_defs.n_vars = n_vars; 4640 } 4641 } 4642 4643 return ret; 4644 free: 4645 free_var_defs(hist_data); 4646 4647 return ret; 4648 } 4649 4650 static int create_hist_fields(struct hist_trigger_data *hist_data, 4651 struct trace_event_file *file) 4652 { 4653 int ret; 4654 4655 ret = parse_var_defs(hist_data); 4656 if (ret) 4657 return ret; 4658 4659 ret = create_val_fields(hist_data, file); 4660 if (ret) 4661 goto out; 4662 4663 ret = create_var_fields(hist_data, file); 4664 if (ret) 4665 goto out; 4666 4667 ret = create_key_fields(hist_data, file); 4668 4669 out: 4670 free_var_defs(hist_data); 4671 4672 return ret; 4673 } 4674 4675 static int is_descending(struct trace_array *tr, const char *str) 4676 { 4677 if (!str) 4678 return 0; 4679 4680 if (strcmp(str, "descending") == 0) 4681 return 1; 4682 4683 if (strcmp(str, "ascending") == 0) 4684 return 0; 4685 4686 hist_err(tr, HIST_ERR_INVALID_SORT_MODIFIER, errpos((char *)str)); 4687 4688 return -EINVAL; 4689 } 4690 4691 static int create_sort_keys(struct hist_trigger_data *hist_data) 4692 { 4693 struct trace_array *tr = hist_data->event_file->tr; 4694 char *fields_str = hist_data->attrs->sort_key_str; 4695 struct tracing_map_sort_key *sort_key; 4696 int descending, ret = 0; 4697 unsigned int i, j, k; 4698 4699 hist_data->n_sort_keys = 1; /* we always have at least one, hitcount */ 4700 4701 if (!fields_str) 4702 goto out; 4703 4704 for (i = 0; i < TRACING_MAP_SORT_KEYS_MAX; i++) { 4705 struct hist_field *hist_field; 4706 char *field_str, *field_name; 4707 const char *test_name; 4708 4709 sort_key = &hist_data->sort_keys[i]; 4710 4711 field_str = strsep(&fields_str, ","); 4712 if (!field_str) 4713 break; 4714 4715 if (!*field_str) { 4716 ret = -EINVAL; 4717 hist_err(tr, HIST_ERR_EMPTY_SORT_FIELD, errpos("sort=")); 4718 break; 4719 } 4720 4721 if ((i == TRACING_MAP_SORT_KEYS_MAX - 1) && fields_str) { 4722 hist_err(tr, HIST_ERR_TOO_MANY_SORT_FIELDS, errpos("sort=")); 4723 ret = -EINVAL; 4724 break; 4725 } 4726 4727 field_name = strsep(&field_str, "."); 4728 if (!field_name || !*field_name) { 4729 ret = -EINVAL; 4730 hist_err(tr, HIST_ERR_EMPTY_SORT_FIELD, errpos("sort=")); 4731 break; 4732 } 4733 4734 if (strcmp(field_name, "hitcount") == 0) { 4735 descending = is_descending(tr, field_str); 4736 if (descending < 0) { 4737 ret = descending; 4738 break; 4739 } 4740 sort_key->descending = descending; 4741 continue; 4742 } 4743 4744 for (j = 1, k = 1; j < hist_data->n_fields; j++) { 4745 unsigned int idx; 4746 4747 hist_field = hist_data->fields[j]; 4748 if (hist_field->flags & HIST_FIELD_FL_VAR) 4749 continue; 4750 4751 idx = k++; 4752 4753 test_name = hist_field_name(hist_field, 0); 4754 4755 if (strcmp(field_name, test_name) == 0) { 4756 sort_key->field_idx = idx; 4757 descending = is_descending(tr, field_str); 4758 if (descending < 0) { 4759 ret = descending; 4760 goto out; 4761 } 4762 sort_key->descending = descending; 4763 break; 4764 } 4765 } 4766 if (j == hist_data->n_fields) { 4767 ret = -EINVAL; 4768 hist_err(tr, HIST_ERR_INVALID_SORT_FIELD, errpos(field_name)); 4769 break; 4770 } 4771 } 4772 4773 hist_data->n_sort_keys = i; 4774 out: 4775 return ret; 4776 } 4777 4778 static void destroy_actions(struct hist_trigger_data *hist_data) 4779 { 4780 unsigned int i; 4781 4782 for (i = 0; i < hist_data->n_actions; i++) { 4783 struct action_data *data = hist_data->actions[i]; 4784 4785 if (data->handler == HANDLER_ONMATCH) 4786 onmatch_destroy(data); 4787 else if (data->handler == HANDLER_ONMAX || 4788 data->handler == HANDLER_ONCHANGE) 4789 track_data_destroy(hist_data, data); 4790 else 4791 kfree(data); 4792 } 4793 } 4794 4795 static int parse_actions(struct hist_trigger_data *hist_data) 4796 { 4797 struct trace_array *tr = hist_data->event_file->tr; 4798 struct action_data *data; 4799 unsigned int i; 4800 int ret = 0; 4801 char *str; 4802 int len; 4803 4804 for (i = 0; i < hist_data->attrs->n_actions; i++) { 4805 enum handler_id hid = 0; 4806 char *action_str; 4807 4808 str = hist_data->attrs->action_str[i]; 4809 4810 if ((len = str_has_prefix(str, "onmatch("))) 4811 hid = HANDLER_ONMATCH; 4812 else if ((len = str_has_prefix(str, "onmax("))) 4813 hid = HANDLER_ONMAX; 4814 else if ((len = str_has_prefix(str, "onchange("))) 4815 hid = HANDLER_ONCHANGE; 4816 4817 action_str = str + len; 4818 4819 switch (hid) { 4820 case HANDLER_ONMATCH: 4821 data = onmatch_parse(tr, action_str); 4822 break; 4823 case HANDLER_ONMAX: 4824 case HANDLER_ONCHANGE: 4825 data = track_data_parse(hist_data, action_str, hid); 4826 break; 4827 default: 4828 data = ERR_PTR(-EINVAL); 4829 break; 4830 } 4831 4832 if (IS_ERR(data)) { 4833 ret = PTR_ERR(data); 4834 break; 4835 } 4836 4837 hist_data->actions[hist_data->n_actions++] = data; 4838 } 4839 4840 return ret; 4841 } 4842 4843 static int create_actions(struct hist_trigger_data *hist_data) 4844 { 4845 struct action_data *data; 4846 unsigned int i; 4847 int ret = 0; 4848 4849 for (i = 0; i < hist_data->attrs->n_actions; i++) { 4850 data = hist_data->actions[i]; 4851 4852 if (data->handler == HANDLER_ONMATCH) { 4853 ret = onmatch_create(hist_data, data); 4854 if (ret) 4855 break; 4856 } else if (data->handler == HANDLER_ONMAX || 4857 data->handler == HANDLER_ONCHANGE) { 4858 ret = track_data_create(hist_data, data); 4859 if (ret) 4860 break; 4861 } else { 4862 ret = -EINVAL; 4863 break; 4864 } 4865 } 4866 4867 return ret; 4868 } 4869 4870 static void print_actions(struct seq_file *m, 4871 struct hist_trigger_data *hist_data, 4872 struct tracing_map_elt *elt) 4873 { 4874 unsigned int i; 4875 4876 for (i = 0; i < hist_data->n_actions; i++) { 4877 struct action_data *data = hist_data->actions[i]; 4878 4879 if (data->action == ACTION_SNAPSHOT) 4880 continue; 4881 4882 if (data->handler == HANDLER_ONMAX || 4883 data->handler == HANDLER_ONCHANGE) 4884 track_data_print(m, hist_data, elt, data); 4885 } 4886 } 4887 4888 static void print_action_spec(struct seq_file *m, 4889 struct hist_trigger_data *hist_data, 4890 struct action_data *data) 4891 { 4892 unsigned int i; 4893 4894 if (data->action == ACTION_SAVE) { 4895 for (i = 0; i < hist_data->n_save_vars; i++) { 4896 seq_printf(m, "%s", hist_data->save_vars[i]->var->var.name); 4897 if (i < hist_data->n_save_vars - 1) 4898 seq_puts(m, ","); 4899 } 4900 } else if (data->action == ACTION_TRACE) { 4901 if (data->use_trace_keyword) 4902 seq_printf(m, "%s", data->synth_event_name); 4903 for (i = 0; i < data->n_params; i++) { 4904 if (i || data->use_trace_keyword) 4905 seq_puts(m, ","); 4906 seq_printf(m, "%s", data->params[i]); 4907 } 4908 } 4909 } 4910 4911 static void print_track_data_spec(struct seq_file *m, 4912 struct hist_trigger_data *hist_data, 4913 struct action_data *data) 4914 { 4915 if (data->handler == HANDLER_ONMAX) 4916 seq_puts(m, ":onmax("); 4917 else if (data->handler == HANDLER_ONCHANGE) 4918 seq_puts(m, ":onchange("); 4919 seq_printf(m, "%s", data->track_data.var_str); 4920 seq_printf(m, ").%s(", data->action_name); 4921 4922 print_action_spec(m, hist_data, data); 4923 4924 seq_puts(m, ")"); 4925 } 4926 4927 static void print_onmatch_spec(struct seq_file *m, 4928 struct hist_trigger_data *hist_data, 4929 struct action_data *data) 4930 { 4931 seq_printf(m, ":onmatch(%s.%s).", data->match_data.event_system, 4932 data->match_data.event); 4933 4934 seq_printf(m, "%s(", data->action_name); 4935 4936 print_action_spec(m, hist_data, data); 4937 4938 seq_puts(m, ")"); 4939 } 4940 4941 static bool actions_match(struct hist_trigger_data *hist_data, 4942 struct hist_trigger_data *hist_data_test) 4943 { 4944 unsigned int i, j; 4945 4946 if (hist_data->n_actions != hist_data_test->n_actions) 4947 return false; 4948 4949 for (i = 0; i < hist_data->n_actions; i++) { 4950 struct action_data *data = hist_data->actions[i]; 4951 struct action_data *data_test = hist_data_test->actions[i]; 4952 char *action_name, *action_name_test; 4953 4954 if (data->handler != data_test->handler) 4955 return false; 4956 if (data->action != data_test->action) 4957 return false; 4958 4959 if (data->n_params != data_test->n_params) 4960 return false; 4961 4962 for (j = 0; j < data->n_params; j++) { 4963 if (strcmp(data->params[j], data_test->params[j]) != 0) 4964 return false; 4965 } 4966 4967 if (data->use_trace_keyword) 4968 action_name = data->synth_event_name; 4969 else 4970 action_name = data->action_name; 4971 4972 if (data_test->use_trace_keyword) 4973 action_name_test = data_test->synth_event_name; 4974 else 4975 action_name_test = data_test->action_name; 4976 4977 if (strcmp(action_name, action_name_test) != 0) 4978 return false; 4979 4980 if (data->handler == HANDLER_ONMATCH) { 4981 if (strcmp(data->match_data.event_system, 4982 data_test->match_data.event_system) != 0) 4983 return false; 4984 if (strcmp(data->match_data.event, 4985 data_test->match_data.event) != 0) 4986 return false; 4987 } else if (data->handler == HANDLER_ONMAX || 4988 data->handler == HANDLER_ONCHANGE) { 4989 if (strcmp(data->track_data.var_str, 4990 data_test->track_data.var_str) != 0) 4991 return false; 4992 } 4993 } 4994 4995 return true; 4996 } 4997 4998 4999 static void print_actions_spec(struct seq_file *m, 5000 struct hist_trigger_data *hist_data) 5001 { 5002 unsigned int i; 5003 5004 for (i = 0; i < hist_data->n_actions; i++) { 5005 struct action_data *data = hist_data->actions[i]; 5006 5007 if (data->handler == HANDLER_ONMATCH) 5008 print_onmatch_spec(m, hist_data, data); 5009 else if (data->handler == HANDLER_ONMAX || 5010 data->handler == HANDLER_ONCHANGE) 5011 print_track_data_spec(m, hist_data, data); 5012 } 5013 } 5014 5015 static void destroy_field_var_hists(struct hist_trigger_data *hist_data) 5016 { 5017 unsigned int i; 5018 5019 for (i = 0; i < hist_data->n_field_var_hists; i++) { 5020 kfree(hist_data->field_var_hists[i]->cmd); 5021 kfree(hist_data->field_var_hists[i]); 5022 } 5023 } 5024 5025 static void destroy_hist_data(struct hist_trigger_data *hist_data) 5026 { 5027 if (!hist_data) 5028 return; 5029 5030 destroy_hist_trigger_attrs(hist_data->attrs); 5031 destroy_hist_fields(hist_data); 5032 tracing_map_destroy(hist_data->map); 5033 5034 destroy_actions(hist_data); 5035 destroy_field_vars(hist_data); 5036 destroy_field_var_hists(hist_data); 5037 5038 kfree(hist_data); 5039 } 5040 5041 static int create_tracing_map_fields(struct hist_trigger_data *hist_data) 5042 { 5043 struct tracing_map *map = hist_data->map; 5044 struct ftrace_event_field *field; 5045 struct hist_field *hist_field; 5046 int i, idx = 0; 5047 5048 for_each_hist_field(i, hist_data) { 5049 hist_field = hist_data->fields[i]; 5050 if (hist_field->flags & HIST_FIELD_FL_KEY) { 5051 tracing_map_cmp_fn_t cmp_fn; 5052 5053 field = hist_field->field; 5054 5055 if (hist_field->flags & HIST_FIELD_FL_STACKTRACE) 5056 cmp_fn = tracing_map_cmp_none; 5057 else if (!field || hist_field->flags & HIST_FIELD_FL_CPU) 5058 cmp_fn = tracing_map_cmp_num(hist_field->size, 5059 hist_field->is_signed); 5060 else if (is_string_field(field)) 5061 cmp_fn = tracing_map_cmp_string; 5062 else 5063 cmp_fn = tracing_map_cmp_num(field->size, 5064 field->is_signed); 5065 idx = tracing_map_add_key_field(map, 5066 hist_field->offset, 5067 cmp_fn); 5068 } else if (!(hist_field->flags & HIST_FIELD_FL_VAR)) 5069 idx = tracing_map_add_sum_field(map); 5070 5071 if (idx < 0) 5072 return idx; 5073 5074 if (hist_field->flags & HIST_FIELD_FL_VAR) { 5075 idx = tracing_map_add_var(map); 5076 if (idx < 0) 5077 return idx; 5078 hist_field->var.idx = idx; 5079 hist_field->var.hist_data = hist_data; 5080 } 5081 } 5082 5083 return 0; 5084 } 5085 5086 static struct hist_trigger_data * 5087 create_hist_data(unsigned int map_bits, 5088 struct hist_trigger_attrs *attrs, 5089 struct trace_event_file *file, 5090 bool remove) 5091 { 5092 const struct tracing_map_ops *map_ops = NULL; 5093 struct hist_trigger_data *hist_data; 5094 int ret = 0; 5095 5096 hist_data = kzalloc(sizeof(*hist_data), GFP_KERNEL); 5097 if (!hist_data) 5098 return ERR_PTR(-ENOMEM); 5099 5100 hist_data->attrs = attrs; 5101 hist_data->remove = remove; 5102 hist_data->event_file = file; 5103 5104 ret = parse_actions(hist_data); 5105 if (ret) 5106 goto free; 5107 5108 ret = create_hist_fields(hist_data, file); 5109 if (ret) 5110 goto free; 5111 5112 ret = create_sort_keys(hist_data); 5113 if (ret) 5114 goto free; 5115 5116 map_ops = &hist_trigger_elt_data_ops; 5117 5118 hist_data->map = tracing_map_create(map_bits, hist_data->key_size, 5119 map_ops, hist_data); 5120 if (IS_ERR(hist_data->map)) { 5121 ret = PTR_ERR(hist_data->map); 5122 hist_data->map = NULL; 5123 goto free; 5124 } 5125 5126 ret = create_tracing_map_fields(hist_data); 5127 if (ret) 5128 goto free; 5129 out: 5130 return hist_data; 5131 free: 5132 hist_data->attrs = NULL; 5133 5134 destroy_hist_data(hist_data); 5135 5136 hist_data = ERR_PTR(ret); 5137 5138 goto out; 5139 } 5140 5141 static void hist_trigger_elt_update(struct hist_trigger_data *hist_data, 5142 struct tracing_map_elt *elt, 5143 struct trace_buffer *buffer, void *rec, 5144 struct ring_buffer_event *rbe, 5145 u64 *var_ref_vals) 5146 { 5147 struct hist_elt_data *elt_data; 5148 struct hist_field *hist_field; 5149 unsigned int i, var_idx; 5150 u64 hist_val; 5151 5152 elt_data = elt->private_data; 5153 elt_data->var_ref_vals = var_ref_vals; 5154 5155 for_each_hist_val_field(i, hist_data) { 5156 hist_field = hist_data->fields[i]; 5157 hist_val = hist_fn_call(hist_field, elt, buffer, rbe, rec); 5158 if (hist_field->flags & HIST_FIELD_FL_VAR) { 5159 var_idx = hist_field->var.idx; 5160 5161 if (hist_field->flags & 5162 (HIST_FIELD_FL_STRING | HIST_FIELD_FL_STACKTRACE)) { 5163 unsigned int str_start, var_str_idx, idx; 5164 char *str, *val_str; 5165 unsigned int size; 5166 5167 str_start = hist_data->n_field_var_str + 5168 hist_data->n_save_var_str; 5169 var_str_idx = hist_field->var_str_idx; 5170 idx = str_start + var_str_idx; 5171 5172 str = elt_data->field_var_str[idx]; 5173 val_str = (char *)(uintptr_t)hist_val; 5174 5175 if (hist_field->flags & HIST_FIELD_FL_STRING) { 5176 size = min(hist_field->size, STR_VAR_LEN_MAX); 5177 strscpy(str, val_str, size); 5178 } else { 5179 char *stack_start = str + sizeof(unsigned long); 5180 int e; 5181 5182 e = stack_trace_save((void *)stack_start, 5183 HIST_STACKTRACE_DEPTH, 5184 HIST_STACKTRACE_SKIP); 5185 if (e < HIST_STACKTRACE_DEPTH - 1) 5186 ((unsigned long *)stack_start)[e] = 0; 5187 *((unsigned long *)str) = e; 5188 } 5189 hist_val = (u64)(uintptr_t)str; 5190 } 5191 tracing_map_set_var(elt, var_idx, hist_val); 5192 continue; 5193 } 5194 tracing_map_update_sum(elt, i, hist_val); 5195 } 5196 5197 for_each_hist_key_field(i, hist_data) { 5198 hist_field = hist_data->fields[i]; 5199 if (hist_field->flags & HIST_FIELD_FL_VAR) { 5200 hist_val = hist_fn_call(hist_field, elt, buffer, rbe, rec); 5201 var_idx = hist_field->var.idx; 5202 tracing_map_set_var(elt, var_idx, hist_val); 5203 } 5204 } 5205 5206 update_field_vars(hist_data, elt, buffer, rbe, rec); 5207 } 5208 5209 static inline void add_to_key(char *compound_key, void *key, 5210 struct hist_field *key_field, void *rec) 5211 { 5212 size_t size = key_field->size; 5213 5214 if (key_field->flags & HIST_FIELD_FL_STRING) { 5215 struct ftrace_event_field *field; 5216 5217 field = key_field->field; 5218 if (field->filter_type == FILTER_DYN_STRING || 5219 field->filter_type == FILTER_RDYN_STRING) 5220 size = *(u32 *)(rec + field->offset) >> 16; 5221 else if (field->filter_type == FILTER_STATIC_STRING) 5222 size = field->size; 5223 5224 /* ensure NULL-termination */ 5225 if (size > key_field->size - 1) 5226 size = key_field->size - 1; 5227 5228 strncpy(compound_key + key_field->offset, (char *)key, size); 5229 } else 5230 memcpy(compound_key + key_field->offset, key, size); 5231 } 5232 5233 static void 5234 hist_trigger_actions(struct hist_trigger_data *hist_data, 5235 struct tracing_map_elt *elt, 5236 struct trace_buffer *buffer, void *rec, 5237 struct ring_buffer_event *rbe, void *key, 5238 u64 *var_ref_vals) 5239 { 5240 struct action_data *data; 5241 unsigned int i; 5242 5243 for (i = 0; i < hist_data->n_actions; i++) { 5244 data = hist_data->actions[i]; 5245 data->fn(hist_data, elt, buffer, rec, rbe, key, data, var_ref_vals); 5246 } 5247 } 5248 5249 static void event_hist_trigger(struct event_trigger_data *data, 5250 struct trace_buffer *buffer, void *rec, 5251 struct ring_buffer_event *rbe) 5252 { 5253 struct hist_trigger_data *hist_data = data->private_data; 5254 bool use_compound_key = (hist_data->n_keys > 1); 5255 unsigned long entries[HIST_STACKTRACE_DEPTH]; 5256 u64 var_ref_vals[TRACING_MAP_VARS_MAX]; 5257 char compound_key[HIST_KEY_SIZE_MAX]; 5258 struct tracing_map_elt *elt = NULL; 5259 struct hist_field *key_field; 5260 u64 field_contents; 5261 void *key = NULL; 5262 unsigned int i; 5263 5264 if (unlikely(!rbe)) 5265 return; 5266 5267 memset(compound_key, 0, hist_data->key_size); 5268 5269 for_each_hist_key_field(i, hist_data) { 5270 key_field = hist_data->fields[i]; 5271 5272 if (key_field->flags & HIST_FIELD_FL_STACKTRACE) { 5273 memset(entries, 0, HIST_STACKTRACE_SIZE); 5274 if (key_field->field) { 5275 unsigned long *stack, n_entries; 5276 5277 field_contents = hist_fn_call(key_field, elt, buffer, rbe, rec); 5278 stack = (unsigned long *)(long)field_contents; 5279 n_entries = *stack; 5280 memcpy(entries, ++stack, n_entries * sizeof(unsigned long)); 5281 } else { 5282 stack_trace_save(entries, HIST_STACKTRACE_DEPTH, 5283 HIST_STACKTRACE_SKIP); 5284 } 5285 key = entries; 5286 } else { 5287 field_contents = hist_fn_call(key_field, elt, buffer, rbe, rec); 5288 if (key_field->flags & HIST_FIELD_FL_STRING) { 5289 key = (void *)(unsigned long)field_contents; 5290 use_compound_key = true; 5291 } else 5292 key = (void *)&field_contents; 5293 } 5294 5295 if (use_compound_key) 5296 add_to_key(compound_key, key, key_field, rec); 5297 } 5298 5299 if (use_compound_key) 5300 key = compound_key; 5301 5302 if (hist_data->n_var_refs && 5303 !resolve_var_refs(hist_data, key, var_ref_vals, false)) 5304 return; 5305 5306 elt = tracing_map_insert(hist_data->map, key); 5307 if (!elt) 5308 return; 5309 5310 hist_trigger_elt_update(hist_data, elt, buffer, rec, rbe, var_ref_vals); 5311 5312 if (resolve_var_refs(hist_data, key, var_ref_vals, true)) 5313 hist_trigger_actions(hist_data, elt, buffer, rec, rbe, key, var_ref_vals); 5314 } 5315 5316 static void hist_trigger_stacktrace_print(struct seq_file *m, 5317 unsigned long *stacktrace_entries, 5318 unsigned int max_entries) 5319 { 5320 unsigned int spaces = 8; 5321 unsigned int i; 5322 5323 for (i = 0; i < max_entries; i++) { 5324 if (!stacktrace_entries[i]) 5325 return; 5326 5327 seq_printf(m, "%*c", 1 + spaces, ' '); 5328 seq_printf(m, "%pS\n", (void*)stacktrace_entries[i]); 5329 } 5330 } 5331 5332 static void hist_trigger_print_key(struct seq_file *m, 5333 struct hist_trigger_data *hist_data, 5334 void *key, 5335 struct tracing_map_elt *elt) 5336 { 5337 struct hist_field *key_field; 5338 bool multiline = false; 5339 const char *field_name; 5340 unsigned int i; 5341 u64 uval; 5342 5343 seq_puts(m, "{ "); 5344 5345 for_each_hist_key_field(i, hist_data) { 5346 key_field = hist_data->fields[i]; 5347 5348 if (i > hist_data->n_vals) 5349 seq_puts(m, ", "); 5350 5351 field_name = hist_field_name(key_field, 0); 5352 5353 if (key_field->flags & HIST_FIELD_FL_HEX) { 5354 uval = *(u64 *)(key + key_field->offset); 5355 seq_printf(m, "%s: %llx", field_name, uval); 5356 } else if (key_field->flags & HIST_FIELD_FL_SYM) { 5357 uval = *(u64 *)(key + key_field->offset); 5358 seq_printf(m, "%s: [%llx] %-45ps", field_name, 5359 uval, (void *)(uintptr_t)uval); 5360 } else if (key_field->flags & HIST_FIELD_FL_SYM_OFFSET) { 5361 uval = *(u64 *)(key + key_field->offset); 5362 seq_printf(m, "%s: [%llx] %-55pS", field_name, 5363 uval, (void *)(uintptr_t)uval); 5364 } else if (key_field->flags & HIST_FIELD_FL_EXECNAME) { 5365 struct hist_elt_data *elt_data = elt->private_data; 5366 char *comm; 5367 5368 if (WARN_ON_ONCE(!elt_data)) 5369 return; 5370 5371 comm = elt_data->comm; 5372 5373 uval = *(u64 *)(key + key_field->offset); 5374 seq_printf(m, "%s: %-16s[%10llu]", field_name, 5375 comm, uval); 5376 } else if (key_field->flags & HIST_FIELD_FL_SYSCALL) { 5377 const char *syscall_name; 5378 5379 uval = *(u64 *)(key + key_field->offset); 5380 syscall_name = get_syscall_name(uval); 5381 if (!syscall_name) 5382 syscall_name = "unknown_syscall"; 5383 5384 seq_printf(m, "%s: %-30s[%3llu]", field_name, 5385 syscall_name, uval); 5386 } else if (key_field->flags & HIST_FIELD_FL_STACKTRACE) { 5387 if (key_field->field) 5388 seq_printf(m, "%s.stacktrace", key_field->field->name); 5389 else 5390 seq_puts(m, "common_stacktrace:\n"); 5391 hist_trigger_stacktrace_print(m, 5392 key + key_field->offset, 5393 HIST_STACKTRACE_DEPTH); 5394 multiline = true; 5395 } else if (key_field->flags & HIST_FIELD_FL_LOG2) { 5396 seq_printf(m, "%s: ~ 2^%-2llu", field_name, 5397 *(u64 *)(key + key_field->offset)); 5398 } else if (key_field->flags & HIST_FIELD_FL_BUCKET) { 5399 unsigned long buckets = key_field->buckets; 5400 uval = *(u64 *)(key + key_field->offset); 5401 seq_printf(m, "%s: ~ %llu-%llu", field_name, 5402 uval, uval + buckets -1); 5403 } else if (key_field->flags & HIST_FIELD_FL_STRING) { 5404 seq_printf(m, "%s: %-50s", field_name, 5405 (char *)(key + key_field->offset)); 5406 } else { 5407 uval = *(u64 *)(key + key_field->offset); 5408 seq_printf(m, "%s: %10llu", field_name, uval); 5409 } 5410 } 5411 5412 if (!multiline) 5413 seq_puts(m, " "); 5414 5415 seq_puts(m, "}"); 5416 } 5417 5418 /* Get the 100 times of the percentage of @val in @total */ 5419 static inline unsigned int __get_percentage(u64 val, u64 total) 5420 { 5421 if (!total) 5422 goto div0; 5423 5424 if (val < (U64_MAX / 10000)) 5425 return (unsigned int)div64_ul(val * 10000, total); 5426 5427 total = div64_u64(total, 10000); 5428 if (!total) 5429 goto div0; 5430 5431 return (unsigned int)div64_ul(val, total); 5432 div0: 5433 return val ? UINT_MAX : 0; 5434 } 5435 5436 #define BAR_CHAR '#' 5437 5438 static inline const char *__fill_bar_str(char *buf, int size, u64 val, u64 max) 5439 { 5440 unsigned int len = __get_percentage(val, max); 5441 int i; 5442 5443 if (len == UINT_MAX) { 5444 snprintf(buf, size, "[ERROR]"); 5445 return buf; 5446 } 5447 5448 len = len * size / 10000; 5449 for (i = 0; i < len && i < size; i++) 5450 buf[i] = BAR_CHAR; 5451 while (i < size) 5452 buf[i++] = ' '; 5453 buf[size] = '\0'; 5454 5455 return buf; 5456 } 5457 5458 struct hist_val_stat { 5459 u64 max; 5460 u64 total; 5461 }; 5462 5463 static void hist_trigger_print_val(struct seq_file *m, unsigned int idx, 5464 const char *field_name, unsigned long flags, 5465 struct hist_val_stat *stats, 5466 struct tracing_map_elt *elt) 5467 { 5468 u64 val = tracing_map_read_sum(elt, idx); 5469 unsigned int pc; 5470 char bar[21]; 5471 5472 if (flags & HIST_FIELD_FL_PERCENT) { 5473 pc = __get_percentage(val, stats[idx].total); 5474 if (pc == UINT_MAX) 5475 seq_printf(m, " %s (%%):[ERROR]", field_name); 5476 else 5477 seq_printf(m, " %s (%%): %3u.%02u", field_name, 5478 pc / 100, pc % 100); 5479 } else if (flags & HIST_FIELD_FL_GRAPH) { 5480 seq_printf(m, " %s: %20s", field_name, 5481 __fill_bar_str(bar, 20, val, stats[idx].max)); 5482 } else if (flags & HIST_FIELD_FL_HEX) { 5483 seq_printf(m, " %s: %10llx", field_name, val); 5484 } else { 5485 seq_printf(m, " %s: %10llu", field_name, val); 5486 } 5487 } 5488 5489 static void hist_trigger_entry_print(struct seq_file *m, 5490 struct hist_trigger_data *hist_data, 5491 struct hist_val_stat *stats, 5492 void *key, 5493 struct tracing_map_elt *elt) 5494 { 5495 const char *field_name; 5496 unsigned int i = HITCOUNT_IDX; 5497 unsigned long flags; 5498 5499 hist_trigger_print_key(m, hist_data, key, elt); 5500 5501 /* At first, show the raw hitcount if !nohitcount */ 5502 if (!hist_data->attrs->no_hitcount) 5503 hist_trigger_print_val(m, i, "hitcount", 0, stats, elt); 5504 5505 for (i = 1; i < hist_data->n_vals; i++) { 5506 field_name = hist_field_name(hist_data->fields[i], 0); 5507 flags = hist_data->fields[i]->flags; 5508 if (flags & HIST_FIELD_FL_VAR || flags & HIST_FIELD_FL_EXPR) 5509 continue; 5510 5511 seq_puts(m, " "); 5512 hist_trigger_print_val(m, i, field_name, flags, stats, elt); 5513 } 5514 5515 print_actions(m, hist_data, elt); 5516 5517 seq_puts(m, "\n"); 5518 } 5519 5520 static int print_entries(struct seq_file *m, 5521 struct hist_trigger_data *hist_data) 5522 { 5523 struct tracing_map_sort_entry **sort_entries = NULL; 5524 struct tracing_map *map = hist_data->map; 5525 int i, j, n_entries; 5526 struct hist_val_stat *stats = NULL; 5527 u64 val; 5528 5529 n_entries = tracing_map_sort_entries(map, hist_data->sort_keys, 5530 hist_data->n_sort_keys, 5531 &sort_entries); 5532 if (n_entries < 0) 5533 return n_entries; 5534 5535 /* Calculate the max and the total for each field if needed. */ 5536 for (j = 0; j < hist_data->n_vals; j++) { 5537 if (!(hist_data->fields[j]->flags & 5538 (HIST_FIELD_FL_PERCENT | HIST_FIELD_FL_GRAPH))) 5539 continue; 5540 if (!stats) { 5541 stats = kcalloc(hist_data->n_vals, sizeof(*stats), 5542 GFP_KERNEL); 5543 if (!stats) { 5544 n_entries = -ENOMEM; 5545 goto out; 5546 } 5547 } 5548 for (i = 0; i < n_entries; i++) { 5549 val = tracing_map_read_sum(sort_entries[i]->elt, j); 5550 stats[j].total += val; 5551 if (stats[j].max < val) 5552 stats[j].max = val; 5553 } 5554 } 5555 5556 for (i = 0; i < n_entries; i++) 5557 hist_trigger_entry_print(m, hist_data, stats, 5558 sort_entries[i]->key, 5559 sort_entries[i]->elt); 5560 5561 kfree(stats); 5562 out: 5563 tracing_map_destroy_sort_entries(sort_entries, n_entries); 5564 5565 return n_entries; 5566 } 5567 5568 static void hist_trigger_show(struct seq_file *m, 5569 struct event_trigger_data *data, int n) 5570 { 5571 struct hist_trigger_data *hist_data; 5572 int n_entries; 5573 5574 if (n > 0) 5575 seq_puts(m, "\n\n"); 5576 5577 seq_puts(m, "# event histogram\n#\n# trigger info: "); 5578 data->ops->print(m, data); 5579 seq_puts(m, "#\n\n"); 5580 5581 hist_data = data->private_data; 5582 n_entries = print_entries(m, hist_data); 5583 if (n_entries < 0) 5584 n_entries = 0; 5585 5586 track_data_snapshot_print(m, hist_data); 5587 5588 seq_printf(m, "\nTotals:\n Hits: %llu\n Entries: %u\n Dropped: %llu\n", 5589 (u64)atomic64_read(&hist_data->map->hits), 5590 n_entries, (u64)atomic64_read(&hist_data->map->drops)); 5591 } 5592 5593 static int hist_show(struct seq_file *m, void *v) 5594 { 5595 struct event_trigger_data *data; 5596 struct trace_event_file *event_file; 5597 int n = 0, ret = 0; 5598 5599 mutex_lock(&event_mutex); 5600 5601 event_file = event_file_file(m->private); 5602 if (unlikely(!event_file)) { 5603 ret = -ENODEV; 5604 goto out_unlock; 5605 } 5606 5607 list_for_each_entry(data, &event_file->triggers, list) { 5608 if (data->cmd_ops->trigger_type == ETT_EVENT_HIST) 5609 hist_trigger_show(m, data, n++); 5610 } 5611 5612 out_unlock: 5613 mutex_unlock(&event_mutex); 5614 5615 return ret; 5616 } 5617 5618 static int event_hist_open(struct inode *inode, struct file *file) 5619 { 5620 int ret; 5621 5622 ret = tracing_open_file_tr(inode, file); 5623 if (ret) 5624 return ret; 5625 5626 /* Clear private_data to avoid warning in single_open() */ 5627 file->private_data = NULL; 5628 return single_open(file, hist_show, file); 5629 } 5630 5631 const struct file_operations event_hist_fops = { 5632 .open = event_hist_open, 5633 .read = seq_read, 5634 .llseek = seq_lseek, 5635 .release = tracing_single_release_file_tr, 5636 }; 5637 5638 #ifdef CONFIG_HIST_TRIGGERS_DEBUG 5639 static void hist_field_debug_show_flags(struct seq_file *m, 5640 unsigned long flags) 5641 { 5642 seq_puts(m, " flags:\n"); 5643 5644 if (flags & HIST_FIELD_FL_KEY) 5645 seq_puts(m, " HIST_FIELD_FL_KEY\n"); 5646 else if (flags & HIST_FIELD_FL_HITCOUNT) 5647 seq_puts(m, " VAL: HIST_FIELD_FL_HITCOUNT\n"); 5648 else if (flags & HIST_FIELD_FL_VAR) 5649 seq_puts(m, " HIST_FIELD_FL_VAR\n"); 5650 else if (flags & HIST_FIELD_FL_VAR_REF) 5651 seq_puts(m, " HIST_FIELD_FL_VAR_REF\n"); 5652 else 5653 seq_puts(m, " VAL: normal u64 value\n"); 5654 5655 if (flags & HIST_FIELD_FL_ALIAS) 5656 seq_puts(m, " HIST_FIELD_FL_ALIAS\n"); 5657 else if (flags & HIST_FIELD_FL_CONST) 5658 seq_puts(m, " HIST_FIELD_FL_CONST\n"); 5659 } 5660 5661 static int hist_field_debug_show(struct seq_file *m, 5662 struct hist_field *field, unsigned long flags) 5663 { 5664 if ((field->flags & flags) != flags) { 5665 seq_printf(m, "ERROR: bad flags - %lx\n", flags); 5666 return -EINVAL; 5667 } 5668 5669 hist_field_debug_show_flags(m, field->flags); 5670 if (field->field) 5671 seq_printf(m, " ftrace_event_field name: %s\n", 5672 field->field->name); 5673 5674 if (field->flags & HIST_FIELD_FL_VAR) { 5675 seq_printf(m, " var.name: %s\n", field->var.name); 5676 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n", 5677 field->var.idx); 5678 } 5679 5680 if (field->flags & HIST_FIELD_FL_CONST) 5681 seq_printf(m, " constant: %llu\n", field->constant); 5682 5683 if (field->flags & HIST_FIELD_FL_ALIAS) 5684 seq_printf(m, " var_ref_idx (into hist_data->var_refs[]): %u\n", 5685 field->var_ref_idx); 5686 5687 if (field->flags & HIST_FIELD_FL_VAR_REF) { 5688 seq_printf(m, " name: %s\n", field->name); 5689 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n", 5690 field->var.idx); 5691 seq_printf(m, " var.hist_data: %p\n", field->var.hist_data); 5692 seq_printf(m, " var_ref_idx (into hist_data->var_refs[]): %u\n", 5693 field->var_ref_idx); 5694 if (field->system) 5695 seq_printf(m, " system: %s\n", field->system); 5696 if (field->event_name) 5697 seq_printf(m, " event_name: %s\n", field->event_name); 5698 } 5699 5700 seq_printf(m, " type: %s\n", field->type); 5701 seq_printf(m, " size: %u\n", field->size); 5702 seq_printf(m, " is_signed: %u\n", field->is_signed); 5703 5704 return 0; 5705 } 5706 5707 static int field_var_debug_show(struct seq_file *m, 5708 struct field_var *field_var, unsigned int i, 5709 bool save_vars) 5710 { 5711 const char *vars_name = save_vars ? "save_vars" : "field_vars"; 5712 struct hist_field *field; 5713 int ret = 0; 5714 5715 seq_printf(m, "\n hist_data->%s[%d]:\n", vars_name, i); 5716 5717 field = field_var->var; 5718 5719 seq_printf(m, "\n %s[%d].var:\n", vars_name, i); 5720 5721 hist_field_debug_show_flags(m, field->flags); 5722 seq_printf(m, " var.name: %s\n", field->var.name); 5723 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n", 5724 field->var.idx); 5725 5726 field = field_var->val; 5727 5728 seq_printf(m, "\n %s[%d].val:\n", vars_name, i); 5729 if (field->field) 5730 seq_printf(m, " ftrace_event_field name: %s\n", 5731 field->field->name); 5732 else { 5733 ret = -EINVAL; 5734 goto out; 5735 } 5736 5737 seq_printf(m, " type: %s\n", field->type); 5738 seq_printf(m, " size: %u\n", field->size); 5739 seq_printf(m, " is_signed: %u\n", field->is_signed); 5740 out: 5741 return ret; 5742 } 5743 5744 static int hist_action_debug_show(struct seq_file *m, 5745 struct action_data *data, int i) 5746 { 5747 int ret = 0; 5748 5749 if (data->handler == HANDLER_ONMAX || 5750 data->handler == HANDLER_ONCHANGE) { 5751 seq_printf(m, "\n hist_data->actions[%d].track_data.var_ref:\n", i); 5752 ret = hist_field_debug_show(m, data->track_data.var_ref, 5753 HIST_FIELD_FL_VAR_REF); 5754 if (ret) 5755 goto out; 5756 5757 seq_printf(m, "\n hist_data->actions[%d].track_data.track_var:\n", i); 5758 ret = hist_field_debug_show(m, data->track_data.track_var, 5759 HIST_FIELD_FL_VAR); 5760 if (ret) 5761 goto out; 5762 } 5763 5764 if (data->handler == HANDLER_ONMATCH) { 5765 seq_printf(m, "\n hist_data->actions[%d].match_data.event_system: %s\n", 5766 i, data->match_data.event_system); 5767 seq_printf(m, " hist_data->actions[%d].match_data.event: %s\n", 5768 i, data->match_data.event); 5769 } 5770 out: 5771 return ret; 5772 } 5773 5774 static int hist_actions_debug_show(struct seq_file *m, 5775 struct hist_trigger_data *hist_data) 5776 { 5777 int i, ret = 0; 5778 5779 if (hist_data->n_actions) 5780 seq_puts(m, "\n action tracking variables (for onmax()/onchange()/onmatch()):\n"); 5781 5782 for (i = 0; i < hist_data->n_actions; i++) { 5783 struct action_data *action = hist_data->actions[i]; 5784 5785 ret = hist_action_debug_show(m, action, i); 5786 if (ret) 5787 goto out; 5788 } 5789 5790 if (hist_data->n_save_vars) 5791 seq_puts(m, "\n save action variables (save() params):\n"); 5792 5793 for (i = 0; i < hist_data->n_save_vars; i++) { 5794 ret = field_var_debug_show(m, hist_data->save_vars[i], i, true); 5795 if (ret) 5796 goto out; 5797 } 5798 out: 5799 return ret; 5800 } 5801 5802 static void hist_trigger_debug_show(struct seq_file *m, 5803 struct event_trigger_data *data, int n) 5804 { 5805 struct hist_trigger_data *hist_data; 5806 int i, ret; 5807 5808 if (n > 0) 5809 seq_puts(m, "\n\n"); 5810 5811 seq_puts(m, "# event histogram\n#\n# trigger info: "); 5812 data->ops->print(m, data); 5813 seq_puts(m, "#\n\n"); 5814 5815 hist_data = data->private_data; 5816 5817 seq_printf(m, "hist_data: %p\n\n", hist_data); 5818 seq_printf(m, " n_vals: %u\n", hist_data->n_vals); 5819 seq_printf(m, " n_keys: %u\n", hist_data->n_keys); 5820 seq_printf(m, " n_fields: %u\n", hist_data->n_fields); 5821 5822 seq_puts(m, "\n val fields:\n\n"); 5823 5824 seq_puts(m, " hist_data->fields[0]:\n"); 5825 ret = hist_field_debug_show(m, hist_data->fields[0], 5826 HIST_FIELD_FL_HITCOUNT); 5827 if (ret) 5828 return; 5829 5830 for (i = 1; i < hist_data->n_vals; i++) { 5831 seq_printf(m, "\n hist_data->fields[%d]:\n", i); 5832 ret = hist_field_debug_show(m, hist_data->fields[i], 0); 5833 if (ret) 5834 return; 5835 } 5836 5837 seq_puts(m, "\n key fields:\n"); 5838 5839 for (i = hist_data->n_vals; i < hist_data->n_fields; i++) { 5840 seq_printf(m, "\n hist_data->fields[%d]:\n", i); 5841 ret = hist_field_debug_show(m, hist_data->fields[i], 5842 HIST_FIELD_FL_KEY); 5843 if (ret) 5844 return; 5845 } 5846 5847 if (hist_data->n_var_refs) 5848 seq_puts(m, "\n variable reference fields:\n"); 5849 5850 for (i = 0; i < hist_data->n_var_refs; i++) { 5851 seq_printf(m, "\n hist_data->var_refs[%d]:\n", i); 5852 ret = hist_field_debug_show(m, hist_data->var_refs[i], 5853 HIST_FIELD_FL_VAR_REF); 5854 if (ret) 5855 return; 5856 } 5857 5858 if (hist_data->n_field_vars) 5859 seq_puts(m, "\n field variables:\n"); 5860 5861 for (i = 0; i < hist_data->n_field_vars; i++) { 5862 ret = field_var_debug_show(m, hist_data->field_vars[i], i, false); 5863 if (ret) 5864 return; 5865 } 5866 5867 ret = hist_actions_debug_show(m, hist_data); 5868 if (ret) 5869 return; 5870 } 5871 5872 static int hist_debug_show(struct seq_file *m, void *v) 5873 { 5874 struct event_trigger_data *data; 5875 struct trace_event_file *event_file; 5876 int n = 0, ret = 0; 5877 5878 mutex_lock(&event_mutex); 5879 5880 event_file = event_file_file(m->private); 5881 if (unlikely(!event_file)) { 5882 ret = -ENODEV; 5883 goto out_unlock; 5884 } 5885 5886 list_for_each_entry(data, &event_file->triggers, list) { 5887 if (data->cmd_ops->trigger_type == ETT_EVENT_HIST) 5888 hist_trigger_debug_show(m, data, n++); 5889 } 5890 5891 out_unlock: 5892 mutex_unlock(&event_mutex); 5893 5894 return ret; 5895 } 5896 5897 static int event_hist_debug_open(struct inode *inode, struct file *file) 5898 { 5899 int ret; 5900 5901 ret = tracing_open_file_tr(inode, file); 5902 if (ret) 5903 return ret; 5904 5905 /* Clear private_data to avoid warning in single_open() */ 5906 file->private_data = NULL; 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 = tracing_single_release_file_tr, 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