1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * trace_events_hist - trace event hist triggers 4 * 5 * Copyright (C) 2015 Tom Zanussi <tom.zanussi@linux.intel.com> 6 */ 7 8 #include <linux/module.h> 9 #include <linux/kallsyms.h> 10 #include <linux/security.h> 11 #include <linux/mutex.h> 12 #include <linux/slab.h> 13 #include <linux/stacktrace.h> 14 #include <linux/rculist.h> 15 #include <linux/tracefs.h> 16 17 /* for gfp flag names */ 18 #include <linux/trace_events.h> 19 #include <trace/events/mmflags.h> 20 21 #include "tracing_map.h" 22 #include "trace_synth.h" 23 24 #define ERRORS \ 25 C(NONE, "No error"), \ 26 C(DUPLICATE_VAR, "Variable already defined"), \ 27 C(VAR_NOT_UNIQUE, "Variable name not unique, need to use fully qualified name (subsys.event.var) for variable"), \ 28 C(TOO_MANY_VARS, "Too many variables defined"), \ 29 C(MALFORMED_ASSIGNMENT, "Malformed assignment"), \ 30 C(NAMED_MISMATCH, "Named hist trigger doesn't match existing named trigger (includes variables)"), \ 31 C(TRIGGER_EEXIST, "Hist trigger already exists"), \ 32 C(TRIGGER_ENOENT_CLEAR, "Can't clear or continue a nonexistent hist trigger"), \ 33 C(SET_CLOCK_FAIL, "Couldn't set trace_clock"), \ 34 C(BAD_FIELD_MODIFIER, "Invalid field modifier"), \ 35 C(TOO_MANY_SUBEXPR, "Too many subexpressions (3 max)"), \ 36 C(TIMESTAMP_MISMATCH, "Timestamp units in expression don't match"), \ 37 C(TOO_MANY_FIELD_VARS, "Too many field variables defined"), \ 38 C(EVENT_FILE_NOT_FOUND, "Event file not found"), \ 39 C(HIST_NOT_FOUND, "Matching event histogram not found"), \ 40 C(HIST_CREATE_FAIL, "Couldn't create histogram for field"), \ 41 C(SYNTH_VAR_NOT_FOUND, "Couldn't find synthetic variable"), \ 42 C(SYNTH_EVENT_NOT_FOUND,"Couldn't find synthetic event"), \ 43 C(SYNTH_TYPE_MISMATCH, "Param type doesn't match synthetic event field type"), \ 44 C(SYNTH_COUNT_MISMATCH, "Param count doesn't match synthetic event field count"), \ 45 C(FIELD_VAR_PARSE_FAIL, "Couldn't parse field variable"), \ 46 C(VAR_CREATE_FIND_FAIL, "Couldn't create or find variable"), \ 47 C(ONX_NOT_VAR, "For onmax(x) or onchange(x), x must be a variable"), \ 48 C(ONX_VAR_NOT_FOUND, "Couldn't find onmax or onchange variable"), \ 49 C(ONX_VAR_CREATE_FAIL, "Couldn't create onmax or onchange variable"), \ 50 C(FIELD_VAR_CREATE_FAIL,"Couldn't create field variable"), \ 51 C(TOO_MANY_PARAMS, "Too many action params"), \ 52 C(PARAM_NOT_FOUND, "Couldn't find param"), \ 53 C(INVALID_PARAM, "Invalid action param"), \ 54 C(ACTION_NOT_FOUND, "No action found"), \ 55 C(NO_SAVE_PARAMS, "No params found for save()"), \ 56 C(TOO_MANY_SAVE_ACTIONS,"Can't have more than one save() action per hist"), \ 57 C(ACTION_MISMATCH, "Handler doesn't support action"), \ 58 C(NO_CLOSING_PAREN, "No closing paren found"), \ 59 C(SUBSYS_NOT_FOUND, "Missing subsystem"), \ 60 C(INVALID_SUBSYS_EVENT, "Invalid subsystem or event name"), \ 61 C(INVALID_REF_KEY, "Using variable references in keys not supported"), \ 62 C(VAR_NOT_FOUND, "Couldn't find variable"), \ 63 C(FIELD_NOT_FOUND, "Couldn't find field"), \ 64 C(EMPTY_ASSIGNMENT, "Empty assignment"), \ 65 C(INVALID_SORT_MODIFIER,"Invalid sort modifier"), \ 66 C(EMPTY_SORT_FIELD, "Empty sort field"), \ 67 C(TOO_MANY_SORT_FIELDS, "Too many sort fields (Max = 2)"), \ 68 C(INVALID_SORT_FIELD, "Sort field must be a key or a val"), \ 69 C(INVALID_STR_OPERAND, "String type can not be an operand in expression"), \ 70 C(EXPECT_NUMBER, "Expecting numeric literal"), \ 71 C(UNARY_MINUS_SUBEXPR, "Unary minus not supported in sub-expressions"), \ 72 C(DIVISION_BY_ZERO, "Division by zero"), \ 73 C(NEED_NOHC_VAL, "Non-hitcount value is required for 'nohitcount'"), 74 75 #undef C 76 #define C(a, b) HIST_ERR_##a 77 78 enum { ERRORS }; 79 80 #undef C 81 #define C(a, b) b 82 83 static const char *err_text[] = { ERRORS }; 84 85 struct hist_field; 86 87 typedef u64 (*hist_field_fn_t) (struct hist_field *field, 88 struct tracing_map_elt *elt, 89 struct trace_buffer *buffer, 90 struct ring_buffer_event *rbe, 91 void *event); 92 93 #define HIST_FIELD_OPERANDS_MAX 2 94 #define HIST_FIELDS_MAX (TRACING_MAP_FIELDS_MAX + TRACING_MAP_VARS_MAX) 95 #define HIST_ACTIONS_MAX 8 96 #define HIST_CONST_DIGITS_MAX 21 97 #define HIST_DIV_SHIFT 20 /* For optimizing division by constants */ 98 99 enum field_op_id { 100 FIELD_OP_NONE, 101 FIELD_OP_PLUS, 102 FIELD_OP_MINUS, 103 FIELD_OP_UNARY_MINUS, 104 FIELD_OP_DIV, 105 FIELD_OP_MULT, 106 }; 107 108 enum hist_field_fn { 109 HIST_FIELD_FN_NOP, 110 HIST_FIELD_FN_VAR_REF, 111 HIST_FIELD_FN_COUNTER, 112 HIST_FIELD_FN_CONST, 113 HIST_FIELD_FN_LOG2, 114 HIST_FIELD_FN_BUCKET, 115 HIST_FIELD_FN_TIMESTAMP, 116 HIST_FIELD_FN_CPU, 117 HIST_FIELD_FN_STRING, 118 HIST_FIELD_FN_DYNSTRING, 119 HIST_FIELD_FN_RELDYNSTRING, 120 HIST_FIELD_FN_PSTRING, 121 HIST_FIELD_FN_S64, 122 HIST_FIELD_FN_U64, 123 HIST_FIELD_FN_S32, 124 HIST_FIELD_FN_U32, 125 HIST_FIELD_FN_S16, 126 HIST_FIELD_FN_U16, 127 HIST_FIELD_FN_S8, 128 HIST_FIELD_FN_U8, 129 HIST_FIELD_FN_UMINUS, 130 HIST_FIELD_FN_MINUS, 131 HIST_FIELD_FN_PLUS, 132 HIST_FIELD_FN_DIV, 133 HIST_FIELD_FN_MULT, 134 HIST_FIELD_FN_DIV_POWER2, 135 HIST_FIELD_FN_DIV_NOT_POWER2, 136 HIST_FIELD_FN_DIV_MULT_SHIFT, 137 HIST_FIELD_FN_EXECNAME, 138 HIST_FIELD_FN_STACK, 139 }; 140 141 /* 142 * A hist_var (histogram variable) contains variable information for 143 * hist_fields having the HIST_FIELD_FL_VAR or HIST_FIELD_FL_VAR_REF 144 * flag set. A hist_var has a variable name e.g. ts0, and is 145 * associated with a given histogram trigger, as specified by 146 * hist_data. The hist_var idx is the unique index assigned to the 147 * variable by the hist trigger's tracing_map. The idx is what is 148 * used to set a variable's value and, by a variable reference, to 149 * retrieve it. 150 */ 151 struct hist_var { 152 char *name; 153 struct hist_trigger_data *hist_data; 154 unsigned int idx; 155 }; 156 157 struct hist_field { 158 struct ftrace_event_field *field; 159 unsigned long flags; 160 unsigned long buckets; 161 const char *type; 162 struct hist_field *operands[HIST_FIELD_OPERANDS_MAX]; 163 struct hist_trigger_data *hist_data; 164 enum hist_field_fn fn_num; 165 unsigned int ref; 166 unsigned int size; 167 unsigned int offset; 168 unsigned int is_signed; 169 170 /* 171 * Variable fields contain variable-specific info in var. 172 */ 173 struct hist_var var; 174 enum field_op_id operator; 175 char *system; 176 char *event_name; 177 178 /* 179 * The name field is used for EXPR and VAR_REF fields. VAR 180 * fields contain the variable name in var.name. 181 */ 182 char *name; 183 184 /* 185 * When a histogram trigger is hit, if it has any references 186 * to variables, the values of those variables are collected 187 * into a var_ref_vals array by resolve_var_refs(). The 188 * current value of each variable is read from the tracing_map 189 * using the hist field's hist_var.idx and entered into the 190 * var_ref_idx entry i.e. var_ref_vals[var_ref_idx]. 191 */ 192 unsigned int var_ref_idx; 193 bool read_once; 194 195 unsigned int var_str_idx; 196 197 /* Numeric literals are represented as u64 */ 198 u64 constant; 199 /* Used to optimize division by constants */ 200 u64 div_multiplier; 201 }; 202 203 static u64 hist_fn_call(struct hist_field *hist_field, 204 struct tracing_map_elt *elt, 205 struct trace_buffer *buffer, 206 struct ring_buffer_event *rbe, 207 void *event); 208 209 static u64 hist_field_const(struct hist_field *field, 210 struct tracing_map_elt *elt, 211 struct trace_buffer *buffer, 212 struct ring_buffer_event *rbe, 213 void *event) 214 { 215 return field->constant; 216 } 217 218 static u64 hist_field_counter(struct hist_field *field, 219 struct tracing_map_elt *elt, 220 struct trace_buffer *buffer, 221 struct ring_buffer_event *rbe, 222 void *event) 223 { 224 return 1; 225 } 226 227 static u64 hist_field_string(struct hist_field *hist_field, 228 struct tracing_map_elt *elt, 229 struct trace_buffer *buffer, 230 struct ring_buffer_event *rbe, 231 void *event) 232 { 233 char *addr = (char *)(event + hist_field->field->offset); 234 235 return (u64)(unsigned long)addr; 236 } 237 238 static u64 hist_field_dynstring(struct hist_field *hist_field, 239 struct tracing_map_elt *elt, 240 struct trace_buffer *buffer, 241 struct ring_buffer_event *rbe, 242 void *event) 243 { 244 u32 str_item = *(u32 *)(event + hist_field->field->offset); 245 int str_loc = str_item & 0xffff; 246 char *addr = (char *)(event + str_loc); 247 248 return (u64)(unsigned long)addr; 249 } 250 251 static u64 hist_field_reldynstring(struct hist_field *hist_field, 252 struct tracing_map_elt *elt, 253 struct trace_buffer *buffer, 254 struct ring_buffer_event *rbe, 255 void *event) 256 { 257 u32 *item = event + hist_field->field->offset; 258 u32 str_item = *item; 259 int str_loc = str_item & 0xffff; 260 char *addr = (char *)&item[1] + str_loc; 261 262 return (u64)(unsigned long)addr; 263 } 264 265 static u64 hist_field_pstring(struct hist_field *hist_field, 266 struct tracing_map_elt *elt, 267 struct trace_buffer *buffer, 268 struct ring_buffer_event *rbe, 269 void *event) 270 { 271 char **addr = (char **)(event + hist_field->field->offset); 272 273 return (u64)(unsigned long)*addr; 274 } 275 276 static u64 hist_field_log2(struct hist_field *hist_field, 277 struct tracing_map_elt *elt, 278 struct trace_buffer *buffer, 279 struct ring_buffer_event *rbe, 280 void *event) 281 { 282 struct hist_field *operand = hist_field->operands[0]; 283 284 u64 val = hist_fn_call(operand, elt, buffer, rbe, event); 285 286 return (u64) ilog2(roundup_pow_of_two(val)); 287 } 288 289 static u64 hist_field_bucket(struct hist_field *hist_field, 290 struct tracing_map_elt *elt, 291 struct trace_buffer *buffer, 292 struct ring_buffer_event *rbe, 293 void *event) 294 { 295 struct hist_field *operand = hist_field->operands[0]; 296 unsigned long buckets = hist_field->buckets; 297 298 u64 val = hist_fn_call(operand, elt, buffer, rbe, event); 299 300 if (WARN_ON_ONCE(!buckets)) 301 return val; 302 303 if (val >= LONG_MAX) 304 val = div64_ul(val, buckets); 305 else 306 val = (u64)((unsigned long)val / buckets); 307 return val * buckets; 308 } 309 310 static u64 hist_field_plus(struct hist_field *hist_field, 311 struct tracing_map_elt *elt, 312 struct trace_buffer *buffer, 313 struct ring_buffer_event *rbe, 314 void *event) 315 { 316 struct hist_field *operand1 = hist_field->operands[0]; 317 struct hist_field *operand2 = hist_field->operands[1]; 318 319 u64 val1 = hist_fn_call(operand1, elt, buffer, rbe, event); 320 u64 val2 = hist_fn_call(operand2, elt, buffer, rbe, event); 321 322 return val1 + val2; 323 } 324 325 static u64 hist_field_minus(struct hist_field *hist_field, 326 struct tracing_map_elt *elt, 327 struct trace_buffer *buffer, 328 struct ring_buffer_event *rbe, 329 void *event) 330 { 331 struct hist_field *operand1 = hist_field->operands[0]; 332 struct hist_field *operand2 = hist_field->operands[1]; 333 334 u64 val1 = hist_fn_call(operand1, elt, buffer, rbe, event); 335 u64 val2 = hist_fn_call(operand2, elt, buffer, rbe, event); 336 337 return val1 - val2; 338 } 339 340 static u64 hist_field_div(struct hist_field *hist_field, 341 struct tracing_map_elt *elt, 342 struct trace_buffer *buffer, 343 struct ring_buffer_event *rbe, 344 void *event) 345 { 346 struct hist_field *operand1 = hist_field->operands[0]; 347 struct hist_field *operand2 = hist_field->operands[1]; 348 349 u64 val1 = hist_fn_call(operand1, elt, buffer, rbe, event); 350 u64 val2 = hist_fn_call(operand2, elt, buffer, rbe, event); 351 352 /* Return -1 for the undefined case */ 353 if (!val2) 354 return -1; 355 356 /* Use shift if the divisor is a power of 2 */ 357 if (!(val2 & (val2 - 1))) 358 return val1 >> __ffs64(val2); 359 360 return div64_u64(val1, val2); 361 } 362 363 static u64 div_by_power_of_two(struct hist_field *hist_field, 364 struct tracing_map_elt *elt, 365 struct trace_buffer *buffer, 366 struct ring_buffer_event *rbe, 367 void *event) 368 { 369 struct hist_field *operand1 = hist_field->operands[0]; 370 struct hist_field *operand2 = hist_field->operands[1]; 371 372 u64 val1 = hist_fn_call(operand1, elt, buffer, rbe, event); 373 374 return val1 >> __ffs64(operand2->constant); 375 } 376 377 static u64 div_by_not_power_of_two(struct hist_field *hist_field, 378 struct tracing_map_elt *elt, 379 struct trace_buffer *buffer, 380 struct ring_buffer_event *rbe, 381 void *event) 382 { 383 struct hist_field *operand1 = hist_field->operands[0]; 384 struct hist_field *operand2 = hist_field->operands[1]; 385 386 u64 val1 = hist_fn_call(operand1, elt, buffer, rbe, event); 387 388 return div64_u64(val1, operand2->constant); 389 } 390 391 static u64 div_by_mult_and_shift(struct hist_field *hist_field, 392 struct tracing_map_elt *elt, 393 struct trace_buffer *buffer, 394 struct ring_buffer_event *rbe, 395 void *event) 396 { 397 struct hist_field *operand1 = hist_field->operands[0]; 398 struct hist_field *operand2 = hist_field->operands[1]; 399 400 u64 val1 = hist_fn_call(operand1, elt, buffer, rbe, event); 401 402 /* 403 * If the divisor is a constant, do a multiplication and shift instead. 404 * 405 * Choose Z = some power of 2. If Y <= Z, then: 406 * X / Y = (X * (Z / Y)) / Z 407 * 408 * (Z / Y) is a constant (mult) which is calculated at parse time, so: 409 * X / Y = (X * mult) / Z 410 * 411 * The division by Z can be replaced by a shift since Z is a power of 2: 412 * X / Y = (X * mult) >> HIST_DIV_SHIFT 413 * 414 * As long, as X < Z the results will not be off by more than 1. 415 */ 416 if (val1 < (1 << HIST_DIV_SHIFT)) { 417 u64 mult = operand2->div_multiplier; 418 419 return (val1 * mult + ((1 << HIST_DIV_SHIFT) - 1)) >> HIST_DIV_SHIFT; 420 } 421 422 return div64_u64(val1, operand2->constant); 423 } 424 425 static u64 hist_field_mult(struct hist_field *hist_field, 426 struct tracing_map_elt *elt, 427 struct trace_buffer *buffer, 428 struct ring_buffer_event *rbe, 429 void *event) 430 { 431 struct hist_field *operand1 = hist_field->operands[0]; 432 struct hist_field *operand2 = hist_field->operands[1]; 433 434 u64 val1 = hist_fn_call(operand1, elt, buffer, rbe, event); 435 u64 val2 = hist_fn_call(operand2, elt, buffer, rbe, event); 436 437 return val1 * val2; 438 } 439 440 static u64 hist_field_unary_minus(struct hist_field *hist_field, 441 struct tracing_map_elt *elt, 442 struct trace_buffer *buffer, 443 struct ring_buffer_event *rbe, 444 void *event) 445 { 446 struct hist_field *operand = hist_field->operands[0]; 447 448 s64 sval = (s64)hist_fn_call(operand, elt, buffer, rbe, event); 449 u64 val = (u64)-sval; 450 451 return val; 452 } 453 454 #define DEFINE_HIST_FIELD_FN(type) \ 455 static u64 hist_field_##type(struct hist_field *hist_field, \ 456 struct tracing_map_elt *elt, \ 457 struct trace_buffer *buffer, \ 458 struct ring_buffer_event *rbe, \ 459 void *event) \ 460 { \ 461 type *addr = (type *)(event + hist_field->field->offset); \ 462 \ 463 return (u64)(unsigned long)*addr; \ 464 } 465 466 DEFINE_HIST_FIELD_FN(s64); 467 DEFINE_HIST_FIELD_FN(u64); 468 DEFINE_HIST_FIELD_FN(s32); 469 DEFINE_HIST_FIELD_FN(u32); 470 DEFINE_HIST_FIELD_FN(s16); 471 DEFINE_HIST_FIELD_FN(u16); 472 DEFINE_HIST_FIELD_FN(s8); 473 DEFINE_HIST_FIELD_FN(u8); 474 475 #define for_each_hist_field(i, hist_data) \ 476 for ((i) = 0; (i) < (hist_data)->n_fields; (i)++) 477 478 #define for_each_hist_val_field(i, hist_data) \ 479 for ((i) = 0; (i) < (hist_data)->n_vals; (i)++) 480 481 #define for_each_hist_key_field(i, hist_data) \ 482 for ((i) = (hist_data)->n_vals; (i) < (hist_data)->n_fields; (i)++) 483 484 #define HITCOUNT_IDX 0 485 #define HIST_KEY_SIZE_MAX (MAX_FILTER_STR_VAL + HIST_STACKTRACE_SIZE) 486 487 enum hist_field_flags { 488 HIST_FIELD_FL_HITCOUNT = 1 << 0, 489 HIST_FIELD_FL_KEY = 1 << 1, 490 HIST_FIELD_FL_STRING = 1 << 2, 491 HIST_FIELD_FL_HEX = 1 << 3, 492 HIST_FIELD_FL_SYM = 1 << 4, 493 HIST_FIELD_FL_SYM_OFFSET = 1 << 5, 494 HIST_FIELD_FL_EXECNAME = 1 << 6, 495 HIST_FIELD_FL_SYSCALL = 1 << 7, 496 HIST_FIELD_FL_STACKTRACE = 1 << 8, 497 HIST_FIELD_FL_LOG2 = 1 << 9, 498 HIST_FIELD_FL_TIMESTAMP = 1 << 10, 499 HIST_FIELD_FL_TIMESTAMP_USECS = 1 << 11, 500 HIST_FIELD_FL_VAR = 1 << 12, 501 HIST_FIELD_FL_EXPR = 1 << 13, 502 HIST_FIELD_FL_VAR_REF = 1 << 14, 503 HIST_FIELD_FL_CPU = 1 << 15, 504 HIST_FIELD_FL_ALIAS = 1 << 16, 505 HIST_FIELD_FL_BUCKET = 1 << 17, 506 HIST_FIELD_FL_CONST = 1 << 18, 507 HIST_FIELD_FL_PERCENT = 1 << 19, 508 HIST_FIELD_FL_GRAPH = 1 << 20, 509 }; 510 511 struct var_defs { 512 unsigned int n_vars; 513 char *name[TRACING_MAP_VARS_MAX]; 514 char *expr[TRACING_MAP_VARS_MAX]; 515 }; 516 517 struct hist_trigger_attrs { 518 char *keys_str; 519 char *vals_str; 520 char *sort_key_str; 521 char *name; 522 char *clock; 523 bool pause; 524 bool cont; 525 bool clear; 526 bool ts_in_usecs; 527 bool no_hitcount; 528 unsigned int map_bits; 529 530 char *assignment_str[TRACING_MAP_VARS_MAX]; 531 unsigned int n_assignments; 532 533 char *action_str[HIST_ACTIONS_MAX]; 534 unsigned int n_actions; 535 536 struct var_defs var_defs; 537 }; 538 539 struct field_var { 540 struct hist_field *var; 541 struct hist_field *val; 542 }; 543 544 struct field_var_hist { 545 struct hist_trigger_data *hist_data; 546 char *cmd; 547 }; 548 549 struct hist_trigger_data { 550 struct hist_field *fields[HIST_FIELDS_MAX]; 551 unsigned int n_vals; 552 unsigned int n_keys; 553 unsigned int n_fields; 554 unsigned int n_vars; 555 unsigned int n_var_str; 556 unsigned int key_size; 557 struct tracing_map_sort_key sort_keys[TRACING_MAP_SORT_KEYS_MAX]; 558 unsigned int n_sort_keys; 559 struct trace_event_file *event_file; 560 struct hist_trigger_attrs *attrs; 561 struct tracing_map *map; 562 bool enable_timestamps; 563 bool remove; 564 struct hist_field *var_refs[TRACING_MAP_VARS_MAX]; 565 unsigned int n_var_refs; 566 567 struct action_data *actions[HIST_ACTIONS_MAX]; 568 unsigned int n_actions; 569 570 struct field_var *field_vars[SYNTH_FIELDS_MAX]; 571 unsigned int n_field_vars; 572 unsigned int n_field_var_str; 573 struct field_var_hist *field_var_hists[SYNTH_FIELDS_MAX]; 574 unsigned int n_field_var_hists; 575 576 struct field_var *save_vars[SYNTH_FIELDS_MAX]; 577 unsigned int n_save_vars; 578 unsigned int n_save_var_str; 579 }; 580 581 struct action_data; 582 583 typedef void (*action_fn_t) (struct hist_trigger_data *hist_data, 584 struct tracing_map_elt *elt, 585 struct trace_buffer *buffer, void *rec, 586 struct ring_buffer_event *rbe, void *key, 587 struct action_data *data, u64 *var_ref_vals); 588 589 typedef bool (*check_track_val_fn_t) (u64 track_val, u64 var_val); 590 591 enum handler_id { 592 HANDLER_ONMATCH = 1, 593 HANDLER_ONMAX, 594 HANDLER_ONCHANGE, 595 }; 596 597 enum action_id { 598 ACTION_SAVE = 1, 599 ACTION_TRACE, 600 ACTION_SNAPSHOT, 601 }; 602 603 struct action_data { 604 enum handler_id handler; 605 enum action_id action; 606 char *action_name; 607 action_fn_t fn; 608 609 unsigned int n_params; 610 char *params[SYNTH_FIELDS_MAX]; 611 612 /* 613 * When a histogram trigger is hit, the values of any 614 * references to variables, including variables being passed 615 * as parameters to synthetic events, are collected into a 616 * var_ref_vals array. This var_ref_idx array is an array of 617 * indices into the var_ref_vals array, one for each synthetic 618 * event param, and is passed to the synthetic event 619 * invocation. 620 */ 621 unsigned int var_ref_idx[SYNTH_FIELDS_MAX]; 622 struct synth_event *synth_event; 623 bool use_trace_keyword; 624 char *synth_event_name; 625 626 union { 627 struct { 628 char *event; 629 char *event_system; 630 } match_data; 631 632 struct { 633 /* 634 * var_str contains the $-unstripped variable 635 * name referenced by var_ref, and used when 636 * printing the action. Because var_ref 637 * creation is deferred to create_actions(), 638 * we need a per-action way to save it until 639 * then, thus var_str. 640 */ 641 char *var_str; 642 643 /* 644 * var_ref refers to the variable being 645 * tracked e.g onmax($var). 646 */ 647 struct hist_field *var_ref; 648 649 /* 650 * track_var contains the 'invisible' tracking 651 * variable created to keep the current 652 * e.g. max value. 653 */ 654 struct hist_field *track_var; 655 656 check_track_val_fn_t check_val; 657 action_fn_t save_data; 658 } track_data; 659 }; 660 }; 661 662 struct track_data { 663 u64 track_val; 664 bool updated; 665 666 unsigned int key_len; 667 void *key; 668 struct tracing_map_elt elt; 669 670 struct action_data *action_data; 671 struct hist_trigger_data *hist_data; 672 }; 673 674 struct hist_elt_data { 675 char *comm; 676 u64 *var_ref_vals; 677 char **field_var_str; 678 int n_field_var_str; 679 }; 680 681 struct snapshot_context { 682 struct tracing_map_elt *elt; 683 void *key; 684 }; 685 686 /* 687 * Returns the specific division function to use if the divisor 688 * is constant. This avoids extra branches when the trigger is hit. 689 */ 690 static enum hist_field_fn hist_field_get_div_fn(struct hist_field *divisor) 691 { 692 u64 div = divisor->constant; 693 694 if (!(div & (div - 1))) 695 return HIST_FIELD_FN_DIV_POWER2; 696 697 /* If the divisor is too large, do a regular division */ 698 if (div > (1 << HIST_DIV_SHIFT)) 699 return HIST_FIELD_FN_DIV_NOT_POWER2; 700 701 divisor->div_multiplier = div64_u64((u64)(1 << HIST_DIV_SHIFT), div); 702 return HIST_FIELD_FN_DIV_MULT_SHIFT; 703 } 704 705 static void track_data_free(struct track_data *track_data) 706 { 707 struct hist_elt_data *elt_data; 708 709 if (!track_data) 710 return; 711 712 kfree(track_data->key); 713 714 elt_data = track_data->elt.private_data; 715 if (elt_data) { 716 kfree(elt_data->comm); 717 kfree(elt_data); 718 } 719 720 kfree(track_data); 721 } 722 723 static struct track_data *track_data_alloc(unsigned int key_len, 724 struct action_data *action_data, 725 struct hist_trigger_data *hist_data) 726 { 727 struct track_data *data = kzalloc(sizeof(*data), GFP_KERNEL); 728 struct hist_elt_data *elt_data; 729 730 if (!data) 731 return ERR_PTR(-ENOMEM); 732 733 data->key = kzalloc(key_len, GFP_KERNEL); 734 if (!data->key) { 735 track_data_free(data); 736 return ERR_PTR(-ENOMEM); 737 } 738 739 data->key_len = key_len; 740 data->action_data = action_data; 741 data->hist_data = hist_data; 742 743 elt_data = kzalloc(sizeof(*elt_data), GFP_KERNEL); 744 if (!elt_data) { 745 track_data_free(data); 746 return ERR_PTR(-ENOMEM); 747 } 748 749 data->elt.private_data = elt_data; 750 751 elt_data->comm = kzalloc(TASK_COMM_LEN, GFP_KERNEL); 752 if (!elt_data->comm) { 753 track_data_free(data); 754 return ERR_PTR(-ENOMEM); 755 } 756 757 return data; 758 } 759 760 #define HIST_PREFIX "hist:" 761 762 static char *last_cmd; 763 static char last_cmd_loc[MAX_FILTER_STR_VAL]; 764 765 static int errpos(char *str) 766 { 767 if (!str || !last_cmd) 768 return 0; 769 770 return err_pos(last_cmd, str); 771 } 772 773 static void last_cmd_set(struct trace_event_file *file, char *str) 774 { 775 const char *system = NULL, *name = NULL; 776 struct trace_event_call *call; 777 778 if (!str) 779 return; 780 781 kfree(last_cmd); 782 783 last_cmd = kasprintf(GFP_KERNEL, HIST_PREFIX "%s", str); 784 if (!last_cmd) 785 return; 786 787 if (file) { 788 call = file->event_call; 789 system = call->class->system; 790 if (system) { 791 name = trace_event_name(call); 792 if (!name) 793 system = NULL; 794 } 795 } 796 797 if (system) 798 snprintf(last_cmd_loc, MAX_FILTER_STR_VAL, HIST_PREFIX "%s:%s", system, name); 799 } 800 801 static void hist_err(struct trace_array *tr, u8 err_type, u16 err_pos) 802 { 803 if (!last_cmd) 804 return; 805 806 tracing_log_err(tr, last_cmd_loc, last_cmd, err_text, 807 err_type, err_pos); 808 } 809 810 static void hist_err_clear(void) 811 { 812 if (last_cmd) 813 last_cmd[0] = '\0'; 814 last_cmd_loc[0] = '\0'; 815 } 816 817 typedef void (*synth_probe_func_t) (void *__data, u64 *var_ref_vals, 818 unsigned int *var_ref_idx); 819 820 static inline void trace_synth(struct synth_event *event, u64 *var_ref_vals, 821 unsigned int *var_ref_idx) 822 { 823 struct tracepoint *tp = event->tp; 824 825 if (unlikely(atomic_read(&tp->key.enabled) > 0)) { 826 struct tracepoint_func *probe_func_ptr; 827 synth_probe_func_t probe_func; 828 void *__data; 829 830 if (!(cpu_online(raw_smp_processor_id()))) 831 return; 832 833 probe_func_ptr = rcu_dereference_sched((tp)->funcs); 834 if (probe_func_ptr) { 835 do { 836 probe_func = probe_func_ptr->func; 837 __data = probe_func_ptr->data; 838 probe_func(__data, var_ref_vals, var_ref_idx); 839 } while ((++probe_func_ptr)->func); 840 } 841 } 842 } 843 844 static void action_trace(struct hist_trigger_data *hist_data, 845 struct tracing_map_elt *elt, 846 struct trace_buffer *buffer, void *rec, 847 struct ring_buffer_event *rbe, void *key, 848 struct action_data *data, u64 *var_ref_vals) 849 { 850 struct synth_event *event = data->synth_event; 851 852 trace_synth(event, var_ref_vals, data->var_ref_idx); 853 } 854 855 struct hist_var_data { 856 struct list_head list; 857 struct hist_trigger_data *hist_data; 858 }; 859 860 static u64 hist_field_timestamp(struct hist_field *hist_field, 861 struct tracing_map_elt *elt, 862 struct trace_buffer *buffer, 863 struct ring_buffer_event *rbe, 864 void *event) 865 { 866 struct hist_trigger_data *hist_data = hist_field->hist_data; 867 struct trace_array *tr = hist_data->event_file->tr; 868 869 u64 ts = ring_buffer_event_time_stamp(buffer, rbe); 870 871 if (hist_data->attrs->ts_in_usecs && trace_clock_in_ns(tr)) 872 ts = ns2usecs(ts); 873 874 return ts; 875 } 876 877 static u64 hist_field_cpu(struct hist_field *hist_field, 878 struct tracing_map_elt *elt, 879 struct trace_buffer *buffer, 880 struct ring_buffer_event *rbe, 881 void *event) 882 { 883 int cpu = smp_processor_id(); 884 885 return cpu; 886 } 887 888 /** 889 * check_field_for_var_ref - Check if a VAR_REF field references a variable 890 * @hist_field: The VAR_REF field to check 891 * @var_data: The hist trigger that owns the variable 892 * @var_idx: The trigger variable identifier 893 * 894 * Check the given VAR_REF field to see whether or not it references 895 * the given variable associated with the given trigger. 896 * 897 * Return: The VAR_REF field if it does reference the variable, NULL if not 898 */ 899 static struct hist_field * 900 check_field_for_var_ref(struct hist_field *hist_field, 901 struct hist_trigger_data *var_data, 902 unsigned int var_idx) 903 { 904 WARN_ON(!(hist_field && hist_field->flags & HIST_FIELD_FL_VAR_REF)); 905 906 if (hist_field && hist_field->var.idx == var_idx && 907 hist_field->var.hist_data == var_data) 908 return hist_field; 909 910 return NULL; 911 } 912 913 /** 914 * find_var_ref - Check if a trigger has a reference to a trigger variable 915 * @hist_data: The hist trigger that might have a reference to the variable 916 * @var_data: The hist trigger that owns the variable 917 * @var_idx: The trigger variable identifier 918 * 919 * Check the list of var_refs[] on the first hist trigger to see 920 * whether any of them are references to the variable on the second 921 * trigger. 922 * 923 * Return: The VAR_REF field referencing the variable if so, NULL if not 924 */ 925 static struct hist_field *find_var_ref(struct hist_trigger_data *hist_data, 926 struct hist_trigger_data *var_data, 927 unsigned int var_idx) 928 { 929 struct hist_field *hist_field; 930 unsigned int i; 931 932 for (i = 0; i < hist_data->n_var_refs; i++) { 933 hist_field = hist_data->var_refs[i]; 934 if (check_field_for_var_ref(hist_field, var_data, var_idx)) 935 return hist_field; 936 } 937 938 return NULL; 939 } 940 941 /** 942 * find_any_var_ref - Check if there is a reference to a given trigger variable 943 * @hist_data: The hist trigger 944 * @var_idx: The trigger variable identifier 945 * 946 * Check to see whether the given variable is currently referenced by 947 * any other trigger. 948 * 949 * The trigger the variable is defined on is explicitly excluded - the 950 * assumption being that a self-reference doesn't prevent a trigger 951 * from being removed. 952 * 953 * Return: The VAR_REF field referencing the variable if so, NULL if not 954 */ 955 static struct hist_field *find_any_var_ref(struct hist_trigger_data *hist_data, 956 unsigned int var_idx) 957 { 958 struct trace_array *tr = hist_data->event_file->tr; 959 struct hist_field *found = NULL; 960 struct hist_var_data *var_data; 961 962 list_for_each_entry(var_data, &tr->hist_vars, list) { 963 if (var_data->hist_data == hist_data) 964 continue; 965 found = find_var_ref(var_data->hist_data, hist_data, var_idx); 966 if (found) 967 break; 968 } 969 970 return found; 971 } 972 973 /** 974 * check_var_refs - Check if there is a reference to any of trigger's variables 975 * @hist_data: The hist trigger 976 * 977 * A trigger can define one or more variables. If any one of them is 978 * currently referenced by any other trigger, this function will 979 * determine that. 980 * 981 * Typically used to determine whether or not a trigger can be removed 982 * - if there are any references to a trigger's variables, it cannot. 983 * 984 * Return: True if there is a reference to any of trigger's variables 985 */ 986 static bool check_var_refs(struct hist_trigger_data *hist_data) 987 { 988 struct hist_field *field; 989 bool found = false; 990 int i; 991 992 for_each_hist_field(i, hist_data) { 993 field = hist_data->fields[i]; 994 if (field && field->flags & HIST_FIELD_FL_VAR) { 995 if (find_any_var_ref(hist_data, field->var.idx)) { 996 found = true; 997 break; 998 } 999 } 1000 } 1001 1002 return found; 1003 } 1004 1005 static struct hist_var_data *find_hist_vars(struct hist_trigger_data *hist_data) 1006 { 1007 struct trace_array *tr = hist_data->event_file->tr; 1008 struct hist_var_data *var_data, *found = NULL; 1009 1010 list_for_each_entry(var_data, &tr->hist_vars, list) { 1011 if (var_data->hist_data == hist_data) { 1012 found = var_data; 1013 break; 1014 } 1015 } 1016 1017 return found; 1018 } 1019 1020 static bool field_has_hist_vars(struct hist_field *hist_field, 1021 unsigned int level) 1022 { 1023 int i; 1024 1025 if (level > 3) 1026 return false; 1027 1028 if (!hist_field) 1029 return false; 1030 1031 if (hist_field->flags & HIST_FIELD_FL_VAR || 1032 hist_field->flags & HIST_FIELD_FL_VAR_REF) 1033 return true; 1034 1035 for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++) { 1036 struct hist_field *operand; 1037 1038 operand = hist_field->operands[i]; 1039 if (field_has_hist_vars(operand, level + 1)) 1040 return true; 1041 } 1042 1043 return false; 1044 } 1045 1046 static bool has_hist_vars(struct hist_trigger_data *hist_data) 1047 { 1048 struct hist_field *hist_field; 1049 int i; 1050 1051 for_each_hist_field(i, hist_data) { 1052 hist_field = hist_data->fields[i]; 1053 if (field_has_hist_vars(hist_field, 0)) 1054 return true; 1055 } 1056 1057 return false; 1058 } 1059 1060 static int save_hist_vars(struct hist_trigger_data *hist_data) 1061 { 1062 struct trace_array *tr = hist_data->event_file->tr; 1063 struct hist_var_data *var_data; 1064 1065 var_data = find_hist_vars(hist_data); 1066 if (var_data) 1067 return 0; 1068 1069 if (tracing_check_open_get_tr(tr)) 1070 return -ENODEV; 1071 1072 var_data = kzalloc(sizeof(*var_data), GFP_KERNEL); 1073 if (!var_data) { 1074 trace_array_put(tr); 1075 return -ENOMEM; 1076 } 1077 1078 var_data->hist_data = hist_data; 1079 list_add(&var_data->list, &tr->hist_vars); 1080 1081 return 0; 1082 } 1083 1084 static void remove_hist_vars(struct hist_trigger_data *hist_data) 1085 { 1086 struct trace_array *tr = hist_data->event_file->tr; 1087 struct hist_var_data *var_data; 1088 1089 var_data = find_hist_vars(hist_data); 1090 if (!var_data) 1091 return; 1092 1093 if (WARN_ON(check_var_refs(hist_data))) 1094 return; 1095 1096 list_del(&var_data->list); 1097 1098 kfree(var_data); 1099 1100 trace_array_put(tr); 1101 } 1102 1103 static struct hist_field *find_var_field(struct hist_trigger_data *hist_data, 1104 const char *var_name) 1105 { 1106 struct hist_field *hist_field, *found = NULL; 1107 int i; 1108 1109 for_each_hist_field(i, hist_data) { 1110 hist_field = hist_data->fields[i]; 1111 if (hist_field && hist_field->flags & HIST_FIELD_FL_VAR && 1112 strcmp(hist_field->var.name, var_name) == 0) { 1113 found = hist_field; 1114 break; 1115 } 1116 } 1117 1118 return found; 1119 } 1120 1121 static struct hist_field *find_var(struct hist_trigger_data *hist_data, 1122 struct trace_event_file *file, 1123 const char *var_name) 1124 { 1125 struct hist_trigger_data *test_data; 1126 struct event_trigger_data *test; 1127 struct hist_field *hist_field; 1128 1129 lockdep_assert_held(&event_mutex); 1130 1131 hist_field = find_var_field(hist_data, var_name); 1132 if (hist_field) 1133 return hist_field; 1134 1135 list_for_each_entry(test, &file->triggers, list) { 1136 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 1137 test_data = test->private_data; 1138 hist_field = find_var_field(test_data, var_name); 1139 if (hist_field) 1140 return hist_field; 1141 } 1142 } 1143 1144 return NULL; 1145 } 1146 1147 static struct trace_event_file *find_var_file(struct trace_array *tr, 1148 char *system, 1149 char *event_name, 1150 char *var_name) 1151 { 1152 struct hist_trigger_data *var_hist_data; 1153 struct hist_var_data *var_data; 1154 struct trace_event_file *file, *found = NULL; 1155 1156 if (system) 1157 return find_event_file(tr, system, event_name); 1158 1159 list_for_each_entry(var_data, &tr->hist_vars, list) { 1160 var_hist_data = var_data->hist_data; 1161 file = var_hist_data->event_file; 1162 if (file == found) 1163 continue; 1164 1165 if (find_var_field(var_hist_data, var_name)) { 1166 if (found) { 1167 hist_err(tr, HIST_ERR_VAR_NOT_UNIQUE, errpos(var_name)); 1168 return NULL; 1169 } 1170 1171 found = file; 1172 } 1173 } 1174 1175 return found; 1176 } 1177 1178 static struct hist_field *find_file_var(struct trace_event_file *file, 1179 const char *var_name) 1180 { 1181 struct hist_trigger_data *test_data; 1182 struct event_trigger_data *test; 1183 struct hist_field *hist_field; 1184 1185 lockdep_assert_held(&event_mutex); 1186 1187 list_for_each_entry(test, &file->triggers, list) { 1188 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 1189 test_data = test->private_data; 1190 hist_field = find_var_field(test_data, var_name); 1191 if (hist_field) 1192 return hist_field; 1193 } 1194 } 1195 1196 return NULL; 1197 } 1198 1199 static struct hist_field * 1200 find_match_var(struct hist_trigger_data *hist_data, char *var_name) 1201 { 1202 struct trace_array *tr = hist_data->event_file->tr; 1203 struct hist_field *hist_field, *found = NULL; 1204 struct trace_event_file *file; 1205 unsigned int i; 1206 1207 for (i = 0; i < hist_data->n_actions; i++) { 1208 struct action_data *data = hist_data->actions[i]; 1209 1210 if (data->handler == HANDLER_ONMATCH) { 1211 char *system = data->match_data.event_system; 1212 char *event_name = data->match_data.event; 1213 1214 file = find_var_file(tr, system, event_name, var_name); 1215 if (!file) 1216 continue; 1217 hist_field = find_file_var(file, var_name); 1218 if (hist_field) { 1219 if (found) { 1220 hist_err(tr, HIST_ERR_VAR_NOT_UNIQUE, 1221 errpos(var_name)); 1222 return ERR_PTR(-EINVAL); 1223 } 1224 1225 found = hist_field; 1226 } 1227 } 1228 } 1229 return found; 1230 } 1231 1232 static struct hist_field *find_event_var(struct hist_trigger_data *hist_data, 1233 char *system, 1234 char *event_name, 1235 char *var_name) 1236 { 1237 struct trace_array *tr = hist_data->event_file->tr; 1238 struct hist_field *hist_field = NULL; 1239 struct trace_event_file *file; 1240 1241 if (!system || !event_name) { 1242 hist_field = find_match_var(hist_data, var_name); 1243 if (IS_ERR(hist_field)) 1244 return NULL; 1245 if (hist_field) 1246 return hist_field; 1247 } 1248 1249 file = find_var_file(tr, system, event_name, var_name); 1250 if (!file) 1251 return NULL; 1252 1253 hist_field = find_file_var(file, var_name); 1254 1255 return hist_field; 1256 } 1257 1258 static u64 hist_field_var_ref(struct hist_field *hist_field, 1259 struct tracing_map_elt *elt, 1260 struct trace_buffer *buffer, 1261 struct ring_buffer_event *rbe, 1262 void *event) 1263 { 1264 struct hist_elt_data *elt_data; 1265 u64 var_val = 0; 1266 1267 if (WARN_ON_ONCE(!elt)) 1268 return var_val; 1269 1270 elt_data = elt->private_data; 1271 var_val = elt_data->var_ref_vals[hist_field->var_ref_idx]; 1272 1273 return var_val; 1274 } 1275 1276 static bool resolve_var_refs(struct hist_trigger_data *hist_data, void *key, 1277 u64 *var_ref_vals, bool self) 1278 { 1279 struct hist_trigger_data *var_data; 1280 struct tracing_map_elt *var_elt; 1281 struct hist_field *hist_field; 1282 unsigned int i, var_idx; 1283 bool resolved = true; 1284 u64 var_val = 0; 1285 1286 for (i = 0; i < hist_data->n_var_refs; i++) { 1287 hist_field = hist_data->var_refs[i]; 1288 var_idx = hist_field->var.idx; 1289 var_data = hist_field->var.hist_data; 1290 1291 if (var_data == NULL) { 1292 resolved = false; 1293 break; 1294 } 1295 1296 if ((self && var_data != hist_data) || 1297 (!self && var_data == hist_data)) 1298 continue; 1299 1300 var_elt = tracing_map_lookup(var_data->map, key); 1301 if (!var_elt) { 1302 resolved = false; 1303 break; 1304 } 1305 1306 if (!tracing_map_var_set(var_elt, var_idx)) { 1307 resolved = false; 1308 break; 1309 } 1310 1311 if (self || !hist_field->read_once) 1312 var_val = tracing_map_read_var(var_elt, var_idx); 1313 else 1314 var_val = tracing_map_read_var_once(var_elt, var_idx); 1315 1316 var_ref_vals[i] = var_val; 1317 } 1318 1319 return resolved; 1320 } 1321 1322 static const char *hist_field_name(struct hist_field *field, 1323 unsigned int level) 1324 { 1325 const char *field_name = ""; 1326 1327 if (WARN_ON_ONCE(!field)) 1328 return field_name; 1329 1330 if (level > 1) 1331 return field_name; 1332 1333 if (field->field) 1334 field_name = field->field->name; 1335 else if (field->flags & HIST_FIELD_FL_LOG2 || 1336 field->flags & HIST_FIELD_FL_ALIAS || 1337 field->flags & HIST_FIELD_FL_BUCKET) 1338 field_name = hist_field_name(field->operands[0], ++level); 1339 else if (field->flags & HIST_FIELD_FL_CPU) 1340 field_name = "common_cpu"; 1341 else if (field->flags & HIST_FIELD_FL_EXPR || 1342 field->flags & HIST_FIELD_FL_VAR_REF) { 1343 if (field->system) { 1344 static char full_name[MAX_FILTER_STR_VAL]; 1345 1346 strcat(full_name, field->system); 1347 strcat(full_name, "."); 1348 strcat(full_name, field->event_name); 1349 strcat(full_name, "."); 1350 strcat(full_name, field->name); 1351 field_name = full_name; 1352 } else 1353 field_name = field->name; 1354 } else if (field->flags & HIST_FIELD_FL_TIMESTAMP) 1355 field_name = "common_timestamp"; 1356 else if (field->flags & HIST_FIELD_FL_STACKTRACE) { 1357 if (field->field) 1358 field_name = field->field->name; 1359 else 1360 field_name = "common_stacktrace"; 1361 } else if (field->flags & HIST_FIELD_FL_HITCOUNT) 1362 field_name = "hitcount"; 1363 1364 if (field_name == NULL) 1365 field_name = ""; 1366 1367 return field_name; 1368 } 1369 1370 static enum hist_field_fn select_value_fn(int field_size, int field_is_signed) 1371 { 1372 switch (field_size) { 1373 case 8: 1374 if (field_is_signed) 1375 return HIST_FIELD_FN_S64; 1376 else 1377 return HIST_FIELD_FN_U64; 1378 case 4: 1379 if (field_is_signed) 1380 return HIST_FIELD_FN_S32; 1381 else 1382 return HIST_FIELD_FN_U32; 1383 case 2: 1384 if (field_is_signed) 1385 return HIST_FIELD_FN_S16; 1386 else 1387 return HIST_FIELD_FN_U16; 1388 case 1: 1389 if (field_is_signed) 1390 return HIST_FIELD_FN_S8; 1391 else 1392 return HIST_FIELD_FN_U8; 1393 } 1394 1395 return HIST_FIELD_FN_NOP; 1396 } 1397 1398 static int parse_map_size(char *str) 1399 { 1400 unsigned long size, map_bits; 1401 int ret; 1402 1403 ret = kstrtoul(str, 0, &size); 1404 if (ret) 1405 goto out; 1406 1407 map_bits = ilog2(roundup_pow_of_two(size)); 1408 if (map_bits < TRACING_MAP_BITS_MIN || 1409 map_bits > TRACING_MAP_BITS_MAX) 1410 ret = -EINVAL; 1411 else 1412 ret = map_bits; 1413 out: 1414 return ret; 1415 } 1416 1417 static void destroy_hist_trigger_attrs(struct hist_trigger_attrs *attrs) 1418 { 1419 unsigned int i; 1420 1421 if (!attrs) 1422 return; 1423 1424 for (i = 0; i < attrs->n_assignments; i++) 1425 kfree(attrs->assignment_str[i]); 1426 1427 for (i = 0; i < attrs->n_actions; i++) 1428 kfree(attrs->action_str[i]); 1429 1430 kfree(attrs->name); 1431 kfree(attrs->sort_key_str); 1432 kfree(attrs->keys_str); 1433 kfree(attrs->vals_str); 1434 kfree(attrs->clock); 1435 kfree(attrs); 1436 } 1437 1438 static int parse_action(char *str, struct hist_trigger_attrs *attrs) 1439 { 1440 int ret = -EINVAL; 1441 1442 if (attrs->n_actions >= HIST_ACTIONS_MAX) 1443 return ret; 1444 1445 if ((str_has_prefix(str, "onmatch(")) || 1446 (str_has_prefix(str, "onmax(")) || 1447 (str_has_prefix(str, "onchange("))) { 1448 attrs->action_str[attrs->n_actions] = kstrdup(str, GFP_KERNEL); 1449 if (!attrs->action_str[attrs->n_actions]) { 1450 ret = -ENOMEM; 1451 return ret; 1452 } 1453 attrs->n_actions++; 1454 ret = 0; 1455 } 1456 return ret; 1457 } 1458 1459 static int parse_assignment(struct trace_array *tr, 1460 char *str, struct hist_trigger_attrs *attrs) 1461 { 1462 int len, ret = 0; 1463 1464 if ((len = str_has_prefix(str, "key=")) || 1465 (len = str_has_prefix(str, "keys="))) { 1466 attrs->keys_str = kstrdup(str + len, GFP_KERNEL); 1467 if (!attrs->keys_str) { 1468 ret = -ENOMEM; 1469 goto out; 1470 } 1471 } else if ((len = str_has_prefix(str, "val=")) || 1472 (len = str_has_prefix(str, "vals=")) || 1473 (len = str_has_prefix(str, "values="))) { 1474 attrs->vals_str = kstrdup(str + len, GFP_KERNEL); 1475 if (!attrs->vals_str) { 1476 ret = -ENOMEM; 1477 goto out; 1478 } 1479 } else if ((len = str_has_prefix(str, "sort="))) { 1480 attrs->sort_key_str = kstrdup(str + len, GFP_KERNEL); 1481 if (!attrs->sort_key_str) { 1482 ret = -ENOMEM; 1483 goto out; 1484 } 1485 } else if (str_has_prefix(str, "name=")) { 1486 attrs->name = kstrdup(str, GFP_KERNEL); 1487 if (!attrs->name) { 1488 ret = -ENOMEM; 1489 goto out; 1490 } 1491 } else if ((len = str_has_prefix(str, "clock="))) { 1492 str += len; 1493 1494 str = strstrip(str); 1495 attrs->clock = kstrdup(str, GFP_KERNEL); 1496 if (!attrs->clock) { 1497 ret = -ENOMEM; 1498 goto out; 1499 } 1500 } else if ((len = str_has_prefix(str, "size="))) { 1501 int map_bits = parse_map_size(str + len); 1502 1503 if (map_bits < 0) { 1504 ret = map_bits; 1505 goto out; 1506 } 1507 attrs->map_bits = map_bits; 1508 } else { 1509 char *assignment; 1510 1511 if (attrs->n_assignments == TRACING_MAP_VARS_MAX) { 1512 hist_err(tr, HIST_ERR_TOO_MANY_VARS, errpos(str)); 1513 ret = -EINVAL; 1514 goto out; 1515 } 1516 1517 assignment = kstrdup(str, GFP_KERNEL); 1518 if (!assignment) { 1519 ret = -ENOMEM; 1520 goto out; 1521 } 1522 1523 attrs->assignment_str[attrs->n_assignments++] = assignment; 1524 } 1525 out: 1526 return ret; 1527 } 1528 1529 static struct hist_trigger_attrs * 1530 parse_hist_trigger_attrs(struct trace_array *tr, char *trigger_str) 1531 { 1532 struct hist_trigger_attrs *attrs; 1533 int ret = 0; 1534 1535 attrs = kzalloc(sizeof(*attrs), GFP_KERNEL); 1536 if (!attrs) 1537 return ERR_PTR(-ENOMEM); 1538 1539 while (trigger_str) { 1540 char *str = strsep(&trigger_str, ":"); 1541 char *rhs; 1542 1543 rhs = strchr(str, '='); 1544 if (rhs) { 1545 if (!strlen(++rhs)) { 1546 ret = -EINVAL; 1547 hist_err(tr, HIST_ERR_EMPTY_ASSIGNMENT, errpos(str)); 1548 goto free; 1549 } 1550 ret = parse_assignment(tr, str, attrs); 1551 if (ret) 1552 goto free; 1553 } else if (strcmp(str, "nohitcount") == 0 || 1554 strcmp(str, "NOHC") == 0) 1555 attrs->no_hitcount = true; 1556 else if (strcmp(str, "pause") == 0) 1557 attrs->pause = true; 1558 else if ((strcmp(str, "cont") == 0) || 1559 (strcmp(str, "continue") == 0)) 1560 attrs->cont = true; 1561 else if (strcmp(str, "clear") == 0) 1562 attrs->clear = true; 1563 else { 1564 ret = parse_action(str, attrs); 1565 if (ret) 1566 goto free; 1567 } 1568 } 1569 1570 if (!attrs->keys_str) { 1571 ret = -EINVAL; 1572 goto free; 1573 } 1574 1575 if (!attrs->clock) { 1576 attrs->clock = kstrdup("global", GFP_KERNEL); 1577 if (!attrs->clock) { 1578 ret = -ENOMEM; 1579 goto free; 1580 } 1581 } 1582 1583 return attrs; 1584 free: 1585 destroy_hist_trigger_attrs(attrs); 1586 1587 return ERR_PTR(ret); 1588 } 1589 1590 static inline void save_comm(char *comm, struct task_struct *task) 1591 { 1592 if (!task->pid) { 1593 strcpy(comm, "<idle>"); 1594 return; 1595 } 1596 1597 if (WARN_ON_ONCE(task->pid < 0)) { 1598 strcpy(comm, "<XXX>"); 1599 return; 1600 } 1601 1602 strncpy(comm, task->comm, TASK_COMM_LEN); 1603 } 1604 1605 static void hist_elt_data_free(struct hist_elt_data *elt_data) 1606 { 1607 unsigned int i; 1608 1609 for (i = 0; i < elt_data->n_field_var_str; i++) 1610 kfree(elt_data->field_var_str[i]); 1611 1612 kfree(elt_data->field_var_str); 1613 1614 kfree(elt_data->comm); 1615 kfree(elt_data); 1616 } 1617 1618 static void hist_trigger_elt_data_free(struct tracing_map_elt *elt) 1619 { 1620 struct hist_elt_data *elt_data = elt->private_data; 1621 1622 hist_elt_data_free(elt_data); 1623 } 1624 1625 static int hist_trigger_elt_data_alloc(struct tracing_map_elt *elt) 1626 { 1627 struct hist_trigger_data *hist_data = elt->map->private_data; 1628 unsigned int size = TASK_COMM_LEN; 1629 struct hist_elt_data *elt_data; 1630 struct hist_field *hist_field; 1631 unsigned int i, n_str; 1632 1633 elt_data = kzalloc(sizeof(*elt_data), GFP_KERNEL); 1634 if (!elt_data) 1635 return -ENOMEM; 1636 1637 for_each_hist_field(i, hist_data) { 1638 hist_field = hist_data->fields[i]; 1639 1640 if (hist_field->flags & HIST_FIELD_FL_EXECNAME) { 1641 elt_data->comm = kzalloc(size, GFP_KERNEL); 1642 if (!elt_data->comm) { 1643 kfree(elt_data); 1644 return -ENOMEM; 1645 } 1646 break; 1647 } 1648 } 1649 1650 n_str = hist_data->n_field_var_str + hist_data->n_save_var_str + 1651 hist_data->n_var_str; 1652 if (n_str > SYNTH_FIELDS_MAX) { 1653 hist_elt_data_free(elt_data); 1654 return -EINVAL; 1655 } 1656 1657 BUILD_BUG_ON(STR_VAR_LEN_MAX & (sizeof(u64) - 1)); 1658 1659 size = STR_VAR_LEN_MAX; 1660 1661 elt_data->field_var_str = kcalloc(n_str, sizeof(char *), GFP_KERNEL); 1662 if (!elt_data->field_var_str) { 1663 hist_elt_data_free(elt_data); 1664 return -EINVAL; 1665 } 1666 elt_data->n_field_var_str = n_str; 1667 1668 for (i = 0; i < n_str; i++) { 1669 elt_data->field_var_str[i] = kzalloc(size, GFP_KERNEL); 1670 if (!elt_data->field_var_str[i]) { 1671 hist_elt_data_free(elt_data); 1672 return -ENOMEM; 1673 } 1674 } 1675 1676 elt->private_data = elt_data; 1677 1678 return 0; 1679 } 1680 1681 static void hist_trigger_elt_data_init(struct tracing_map_elt *elt) 1682 { 1683 struct hist_elt_data *elt_data = elt->private_data; 1684 1685 if (elt_data->comm) 1686 save_comm(elt_data->comm, current); 1687 } 1688 1689 static const struct tracing_map_ops hist_trigger_elt_data_ops = { 1690 .elt_alloc = hist_trigger_elt_data_alloc, 1691 .elt_free = hist_trigger_elt_data_free, 1692 .elt_init = hist_trigger_elt_data_init, 1693 }; 1694 1695 static const char *get_hist_field_flags(struct hist_field *hist_field) 1696 { 1697 const char *flags_str = NULL; 1698 1699 if (hist_field->flags & HIST_FIELD_FL_HEX) 1700 flags_str = "hex"; 1701 else if (hist_field->flags & HIST_FIELD_FL_SYM) 1702 flags_str = "sym"; 1703 else if (hist_field->flags & HIST_FIELD_FL_SYM_OFFSET) 1704 flags_str = "sym-offset"; 1705 else if (hist_field->flags & HIST_FIELD_FL_EXECNAME) 1706 flags_str = "execname"; 1707 else if (hist_field->flags & HIST_FIELD_FL_SYSCALL) 1708 flags_str = "syscall"; 1709 else if (hist_field->flags & HIST_FIELD_FL_LOG2) 1710 flags_str = "log2"; 1711 else if (hist_field->flags & HIST_FIELD_FL_BUCKET) 1712 flags_str = "buckets"; 1713 else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP_USECS) 1714 flags_str = "usecs"; 1715 else if (hist_field->flags & HIST_FIELD_FL_PERCENT) 1716 flags_str = "percent"; 1717 else if (hist_field->flags & HIST_FIELD_FL_GRAPH) 1718 flags_str = "graph"; 1719 else if (hist_field->flags & HIST_FIELD_FL_STACKTRACE) 1720 flags_str = "stacktrace"; 1721 1722 return flags_str; 1723 } 1724 1725 static void expr_field_str(struct hist_field *field, char *expr) 1726 { 1727 if (field->flags & HIST_FIELD_FL_VAR_REF) 1728 strcat(expr, "$"); 1729 else if (field->flags & HIST_FIELD_FL_CONST) { 1730 char str[HIST_CONST_DIGITS_MAX]; 1731 1732 snprintf(str, HIST_CONST_DIGITS_MAX, "%llu", field->constant); 1733 strcat(expr, str); 1734 } 1735 1736 strcat(expr, hist_field_name(field, 0)); 1737 1738 if (field->flags && !(field->flags & HIST_FIELD_FL_VAR_REF)) { 1739 const char *flags_str = get_hist_field_flags(field); 1740 1741 if (flags_str) { 1742 strcat(expr, "."); 1743 strcat(expr, flags_str); 1744 } 1745 } 1746 } 1747 1748 static char *expr_str(struct hist_field *field, unsigned int level) 1749 { 1750 char *expr; 1751 1752 if (level > 1) 1753 return NULL; 1754 1755 expr = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL); 1756 if (!expr) 1757 return NULL; 1758 1759 if (!field->operands[0]) { 1760 expr_field_str(field, expr); 1761 return expr; 1762 } 1763 1764 if (field->operator == FIELD_OP_UNARY_MINUS) { 1765 char *subexpr; 1766 1767 strcat(expr, "-("); 1768 subexpr = expr_str(field->operands[0], ++level); 1769 if (!subexpr) { 1770 kfree(expr); 1771 return NULL; 1772 } 1773 strcat(expr, subexpr); 1774 strcat(expr, ")"); 1775 1776 kfree(subexpr); 1777 1778 return expr; 1779 } 1780 1781 expr_field_str(field->operands[0], expr); 1782 1783 switch (field->operator) { 1784 case FIELD_OP_MINUS: 1785 strcat(expr, "-"); 1786 break; 1787 case FIELD_OP_PLUS: 1788 strcat(expr, "+"); 1789 break; 1790 case FIELD_OP_DIV: 1791 strcat(expr, "/"); 1792 break; 1793 case FIELD_OP_MULT: 1794 strcat(expr, "*"); 1795 break; 1796 default: 1797 kfree(expr); 1798 return NULL; 1799 } 1800 1801 expr_field_str(field->operands[1], expr); 1802 1803 return expr; 1804 } 1805 1806 /* 1807 * If field_op != FIELD_OP_NONE, *sep points to the root operator 1808 * of the expression tree to be evaluated. 1809 */ 1810 static int contains_operator(char *str, char **sep) 1811 { 1812 enum field_op_id field_op = FIELD_OP_NONE; 1813 char *minus_op, *plus_op, *div_op, *mult_op; 1814 1815 1816 /* 1817 * Report the last occurrence of the operators first, so that the 1818 * expression is evaluated left to right. This is important since 1819 * subtraction and division are not associative. 1820 * 1821 * e.g 1822 * 64/8/4/2 is 1, i.e 64/8/4/2 = ((64/8)/4)/2 1823 * 14-7-5-2 is 0, i.e 14-7-5-2 = ((14-7)-5)-2 1824 */ 1825 1826 /* 1827 * First, find lower precedence addition and subtraction 1828 * since the expression will be evaluated recursively. 1829 */ 1830 minus_op = strrchr(str, '-'); 1831 if (minus_op) { 1832 /* 1833 * Unary minus is not supported in sub-expressions. If 1834 * present, it is always the next root operator. 1835 */ 1836 if (minus_op == str) { 1837 field_op = FIELD_OP_UNARY_MINUS; 1838 goto out; 1839 } 1840 1841 field_op = FIELD_OP_MINUS; 1842 } 1843 1844 plus_op = strrchr(str, '+'); 1845 if (plus_op || minus_op) { 1846 /* 1847 * For operators of the same precedence use to rightmost as the 1848 * root, so that the expression is evaluated left to right. 1849 */ 1850 if (plus_op > minus_op) 1851 field_op = FIELD_OP_PLUS; 1852 goto out; 1853 } 1854 1855 /* 1856 * Multiplication and division have higher precedence than addition and 1857 * subtraction. 1858 */ 1859 div_op = strrchr(str, '/'); 1860 if (div_op) 1861 field_op = FIELD_OP_DIV; 1862 1863 mult_op = strrchr(str, '*'); 1864 /* 1865 * For operators of the same precedence use to rightmost as the 1866 * root, so that the expression is evaluated left to right. 1867 */ 1868 if (mult_op > div_op) 1869 field_op = FIELD_OP_MULT; 1870 1871 out: 1872 if (sep) { 1873 switch (field_op) { 1874 case FIELD_OP_UNARY_MINUS: 1875 case FIELD_OP_MINUS: 1876 *sep = minus_op; 1877 break; 1878 case FIELD_OP_PLUS: 1879 *sep = plus_op; 1880 break; 1881 case FIELD_OP_DIV: 1882 *sep = div_op; 1883 break; 1884 case FIELD_OP_MULT: 1885 *sep = mult_op; 1886 break; 1887 case FIELD_OP_NONE: 1888 default: 1889 *sep = NULL; 1890 break; 1891 } 1892 } 1893 1894 return field_op; 1895 } 1896 1897 static void get_hist_field(struct hist_field *hist_field) 1898 { 1899 hist_field->ref++; 1900 } 1901 1902 static void __destroy_hist_field(struct hist_field *hist_field) 1903 { 1904 if (--hist_field->ref > 1) 1905 return; 1906 1907 kfree(hist_field->var.name); 1908 kfree(hist_field->name); 1909 1910 /* Can likely be a const */ 1911 kfree_const(hist_field->type); 1912 1913 kfree(hist_field->system); 1914 kfree(hist_field->event_name); 1915 1916 kfree(hist_field); 1917 } 1918 1919 static void destroy_hist_field(struct hist_field *hist_field, 1920 unsigned int level) 1921 { 1922 unsigned int i; 1923 1924 if (level > 3) 1925 return; 1926 1927 if (!hist_field) 1928 return; 1929 1930 if (hist_field->flags & HIST_FIELD_FL_VAR_REF) 1931 return; /* var refs will be destroyed separately */ 1932 1933 for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++) 1934 destroy_hist_field(hist_field->operands[i], level + 1); 1935 1936 __destroy_hist_field(hist_field); 1937 } 1938 1939 static struct hist_field *create_hist_field(struct hist_trigger_data *hist_data, 1940 struct ftrace_event_field *field, 1941 unsigned long flags, 1942 char *var_name) 1943 { 1944 struct hist_field *hist_field; 1945 1946 if (field && is_function_field(field)) 1947 return NULL; 1948 1949 hist_field = kzalloc(sizeof(struct hist_field), GFP_KERNEL); 1950 if (!hist_field) 1951 return NULL; 1952 1953 hist_field->ref = 1; 1954 1955 hist_field->hist_data = hist_data; 1956 1957 if (flags & HIST_FIELD_FL_EXPR || flags & HIST_FIELD_FL_ALIAS) 1958 goto out; /* caller will populate */ 1959 1960 if (flags & HIST_FIELD_FL_VAR_REF) { 1961 hist_field->fn_num = HIST_FIELD_FN_VAR_REF; 1962 goto out; 1963 } 1964 1965 if (flags & HIST_FIELD_FL_HITCOUNT) { 1966 hist_field->fn_num = HIST_FIELD_FN_COUNTER; 1967 hist_field->size = sizeof(u64); 1968 hist_field->type = "u64"; 1969 goto out; 1970 } 1971 1972 if (flags & HIST_FIELD_FL_CONST) { 1973 hist_field->fn_num = HIST_FIELD_FN_CONST; 1974 hist_field->size = sizeof(u64); 1975 hist_field->type = kstrdup("u64", GFP_KERNEL); 1976 if (!hist_field->type) 1977 goto free; 1978 goto out; 1979 } 1980 1981 if (flags & HIST_FIELD_FL_STACKTRACE) { 1982 if (field) 1983 hist_field->fn_num = HIST_FIELD_FN_STACK; 1984 else 1985 hist_field->fn_num = HIST_FIELD_FN_NOP; 1986 hist_field->size = HIST_STACKTRACE_SIZE; 1987 hist_field->type = kstrdup_const("unsigned long[]", GFP_KERNEL); 1988 if (!hist_field->type) 1989 goto free; 1990 goto out; 1991 } 1992 1993 if (flags & (HIST_FIELD_FL_LOG2 | HIST_FIELD_FL_BUCKET)) { 1994 unsigned long fl = flags & ~(HIST_FIELD_FL_LOG2 | HIST_FIELD_FL_BUCKET); 1995 hist_field->fn_num = flags & HIST_FIELD_FL_LOG2 ? HIST_FIELD_FN_LOG2 : 1996 HIST_FIELD_FN_BUCKET; 1997 hist_field->operands[0] = create_hist_field(hist_data, field, fl, NULL); 1998 if (!hist_field->operands[0]) 1999 goto free; 2000 hist_field->size = hist_field->operands[0]->size; 2001 hist_field->type = kstrdup_const(hist_field->operands[0]->type, GFP_KERNEL); 2002 if (!hist_field->type) 2003 goto free; 2004 goto out; 2005 } 2006 2007 if (flags & HIST_FIELD_FL_TIMESTAMP) { 2008 hist_field->fn_num = HIST_FIELD_FN_TIMESTAMP; 2009 hist_field->size = sizeof(u64); 2010 hist_field->type = "u64"; 2011 goto out; 2012 } 2013 2014 if (flags & HIST_FIELD_FL_CPU) { 2015 hist_field->fn_num = HIST_FIELD_FN_CPU; 2016 hist_field->size = sizeof(int); 2017 hist_field->type = "unsigned int"; 2018 goto out; 2019 } 2020 2021 if (WARN_ON_ONCE(!field)) 2022 goto out; 2023 2024 /* Pointers to strings are just pointers and dangerous to dereference */ 2025 if (is_string_field(field) && 2026 (field->filter_type != FILTER_PTR_STRING)) { 2027 flags |= HIST_FIELD_FL_STRING; 2028 2029 hist_field->size = MAX_FILTER_STR_VAL; 2030 hist_field->type = kstrdup_const(field->type, GFP_KERNEL); 2031 if (!hist_field->type) 2032 goto free; 2033 2034 if (field->filter_type == FILTER_STATIC_STRING) { 2035 hist_field->fn_num = HIST_FIELD_FN_STRING; 2036 hist_field->size = field->size; 2037 } else if (field->filter_type == FILTER_DYN_STRING) { 2038 hist_field->fn_num = HIST_FIELD_FN_DYNSTRING; 2039 } else if (field->filter_type == FILTER_RDYN_STRING) 2040 hist_field->fn_num = HIST_FIELD_FN_RELDYNSTRING; 2041 else 2042 hist_field->fn_num = HIST_FIELD_FN_PSTRING; 2043 } else { 2044 hist_field->size = field->size; 2045 hist_field->is_signed = field->is_signed; 2046 hist_field->type = kstrdup_const(field->type, GFP_KERNEL); 2047 if (!hist_field->type) 2048 goto free; 2049 2050 hist_field->fn_num = select_value_fn(field->size, 2051 field->is_signed); 2052 if (hist_field->fn_num == HIST_FIELD_FN_NOP) { 2053 destroy_hist_field(hist_field, 0); 2054 return NULL; 2055 } 2056 } 2057 out: 2058 hist_field->field = field; 2059 hist_field->flags = flags; 2060 2061 if (var_name) { 2062 hist_field->var.name = kstrdup(var_name, GFP_KERNEL); 2063 if (!hist_field->var.name) 2064 goto free; 2065 } 2066 2067 return hist_field; 2068 free: 2069 destroy_hist_field(hist_field, 0); 2070 return NULL; 2071 } 2072 2073 static void destroy_hist_fields(struct hist_trigger_data *hist_data) 2074 { 2075 unsigned int i; 2076 2077 for (i = 0; i < HIST_FIELDS_MAX; i++) { 2078 if (hist_data->fields[i]) { 2079 destroy_hist_field(hist_data->fields[i], 0); 2080 hist_data->fields[i] = NULL; 2081 } 2082 } 2083 2084 for (i = 0; i < hist_data->n_var_refs; i++) { 2085 WARN_ON(!(hist_data->var_refs[i]->flags & HIST_FIELD_FL_VAR_REF)); 2086 __destroy_hist_field(hist_data->var_refs[i]); 2087 hist_data->var_refs[i] = NULL; 2088 } 2089 } 2090 2091 static int init_var_ref(struct hist_field *ref_field, 2092 struct hist_field *var_field, 2093 char *system, char *event_name) 2094 { 2095 int err = 0; 2096 2097 ref_field->var.idx = var_field->var.idx; 2098 ref_field->var.hist_data = var_field->hist_data; 2099 ref_field->size = var_field->size; 2100 ref_field->is_signed = var_field->is_signed; 2101 ref_field->flags |= var_field->flags & 2102 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS); 2103 2104 if (system) { 2105 ref_field->system = kstrdup(system, GFP_KERNEL); 2106 if (!ref_field->system) 2107 return -ENOMEM; 2108 } 2109 2110 if (event_name) { 2111 ref_field->event_name = kstrdup(event_name, GFP_KERNEL); 2112 if (!ref_field->event_name) { 2113 err = -ENOMEM; 2114 goto free; 2115 } 2116 } 2117 2118 if (var_field->var.name) { 2119 ref_field->name = kstrdup(var_field->var.name, GFP_KERNEL); 2120 if (!ref_field->name) { 2121 err = -ENOMEM; 2122 goto free; 2123 } 2124 } else if (var_field->name) { 2125 ref_field->name = kstrdup(var_field->name, GFP_KERNEL); 2126 if (!ref_field->name) { 2127 err = -ENOMEM; 2128 goto free; 2129 } 2130 } 2131 2132 ref_field->type = kstrdup_const(var_field->type, GFP_KERNEL); 2133 if (!ref_field->type) { 2134 err = -ENOMEM; 2135 goto free; 2136 } 2137 out: 2138 return err; 2139 free: 2140 kfree(ref_field->system); 2141 ref_field->system = NULL; 2142 kfree(ref_field->event_name); 2143 ref_field->event_name = NULL; 2144 kfree(ref_field->name); 2145 ref_field->name = NULL; 2146 2147 goto out; 2148 } 2149 2150 static int find_var_ref_idx(struct hist_trigger_data *hist_data, 2151 struct hist_field *var_field) 2152 { 2153 struct hist_field *ref_field; 2154 int i; 2155 2156 for (i = 0; i < hist_data->n_var_refs; i++) { 2157 ref_field = hist_data->var_refs[i]; 2158 if (ref_field->var.idx == var_field->var.idx && 2159 ref_field->var.hist_data == var_field->hist_data) 2160 return i; 2161 } 2162 2163 return -ENOENT; 2164 } 2165 2166 /** 2167 * create_var_ref - Create a variable reference and attach it to trigger 2168 * @hist_data: The trigger that will be referencing the variable 2169 * @var_field: The VAR field to create a reference to 2170 * @system: The optional system string 2171 * @event_name: The optional event_name string 2172 * 2173 * Given a variable hist_field, create a VAR_REF hist_field that 2174 * represents a reference to it. 2175 * 2176 * This function also adds the reference to the trigger that 2177 * now references the variable. 2178 * 2179 * Return: The VAR_REF field if successful, NULL if not 2180 */ 2181 static struct hist_field *create_var_ref(struct hist_trigger_data *hist_data, 2182 struct hist_field *var_field, 2183 char *system, char *event_name) 2184 { 2185 unsigned long flags = HIST_FIELD_FL_VAR_REF; 2186 struct hist_field *ref_field; 2187 int i; 2188 2189 /* Check if the variable already exists */ 2190 for (i = 0; i < hist_data->n_var_refs; i++) { 2191 ref_field = hist_data->var_refs[i]; 2192 if (ref_field->var.idx == var_field->var.idx && 2193 ref_field->var.hist_data == var_field->hist_data) { 2194 get_hist_field(ref_field); 2195 return ref_field; 2196 } 2197 } 2198 /* Sanity check to avoid out-of-bound write on 'hist_data->var_refs' */ 2199 if (hist_data->n_var_refs >= TRACING_MAP_VARS_MAX) 2200 return NULL; 2201 ref_field = create_hist_field(var_field->hist_data, NULL, flags, NULL); 2202 if (ref_field) { 2203 if (init_var_ref(ref_field, var_field, system, event_name)) { 2204 destroy_hist_field(ref_field, 0); 2205 return NULL; 2206 } 2207 2208 hist_data->var_refs[hist_data->n_var_refs] = ref_field; 2209 ref_field->var_ref_idx = hist_data->n_var_refs++; 2210 } 2211 2212 return ref_field; 2213 } 2214 2215 static bool is_var_ref(char *var_name) 2216 { 2217 if (!var_name || strlen(var_name) < 2 || var_name[0] != '$') 2218 return false; 2219 2220 return true; 2221 } 2222 2223 static char *field_name_from_var(struct hist_trigger_data *hist_data, 2224 char *var_name) 2225 { 2226 char *name, *field; 2227 unsigned int i; 2228 2229 for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) { 2230 name = hist_data->attrs->var_defs.name[i]; 2231 2232 if (strcmp(var_name, name) == 0) { 2233 field = hist_data->attrs->var_defs.expr[i]; 2234 if (contains_operator(field, NULL) || is_var_ref(field)) 2235 continue; 2236 return field; 2237 } 2238 } 2239 2240 return NULL; 2241 } 2242 2243 static char *local_field_var_ref(struct hist_trigger_data *hist_data, 2244 char *system, char *event_name, 2245 char *var_name) 2246 { 2247 struct trace_event_call *call; 2248 2249 if (system && event_name) { 2250 call = hist_data->event_file->event_call; 2251 2252 if (strcmp(system, call->class->system) != 0) 2253 return NULL; 2254 2255 if (strcmp(event_name, trace_event_name(call)) != 0) 2256 return NULL; 2257 } 2258 2259 if (!!system != !!event_name) 2260 return NULL; 2261 2262 if (!is_var_ref(var_name)) 2263 return NULL; 2264 2265 var_name++; 2266 2267 return field_name_from_var(hist_data, var_name); 2268 } 2269 2270 static struct hist_field *parse_var_ref(struct hist_trigger_data *hist_data, 2271 char *system, char *event_name, 2272 char *var_name) 2273 { 2274 struct hist_field *var_field = NULL, *ref_field = NULL; 2275 struct trace_array *tr = hist_data->event_file->tr; 2276 2277 if (!is_var_ref(var_name)) 2278 return NULL; 2279 2280 var_name++; 2281 2282 var_field = find_event_var(hist_data, system, event_name, var_name); 2283 if (var_field) 2284 ref_field = create_var_ref(hist_data, var_field, 2285 system, event_name); 2286 2287 if (!ref_field) 2288 hist_err(tr, HIST_ERR_VAR_NOT_FOUND, errpos(var_name)); 2289 2290 return ref_field; 2291 } 2292 2293 static struct ftrace_event_field * 2294 parse_field(struct hist_trigger_data *hist_data, struct trace_event_file *file, 2295 char *field_str, unsigned long *flags, unsigned long *buckets) 2296 { 2297 struct ftrace_event_field *field = NULL; 2298 char *field_name, *modifier, *str; 2299 struct trace_array *tr = file->tr; 2300 2301 modifier = str = kstrdup(field_str, GFP_KERNEL); 2302 if (!modifier) 2303 return ERR_PTR(-ENOMEM); 2304 2305 field_name = strsep(&modifier, "."); 2306 if (modifier) { 2307 if (strcmp(modifier, "hex") == 0) 2308 *flags |= HIST_FIELD_FL_HEX; 2309 else if (strcmp(modifier, "sym") == 0) 2310 *flags |= HIST_FIELD_FL_SYM; 2311 /* 2312 * 'sym-offset' occurrences in the trigger string are modified 2313 * to 'symXoffset' to simplify arithmetic expression parsing. 2314 */ 2315 else if (strcmp(modifier, "symXoffset") == 0) 2316 *flags |= HIST_FIELD_FL_SYM_OFFSET; 2317 else if ((strcmp(modifier, "execname") == 0) && 2318 (strcmp(field_name, "common_pid") == 0)) 2319 *flags |= HIST_FIELD_FL_EXECNAME; 2320 else if (strcmp(modifier, "syscall") == 0) 2321 *flags |= HIST_FIELD_FL_SYSCALL; 2322 else if (strcmp(modifier, "stacktrace") == 0) 2323 *flags |= HIST_FIELD_FL_STACKTRACE; 2324 else if (strcmp(modifier, "log2") == 0) 2325 *flags |= HIST_FIELD_FL_LOG2; 2326 else if (strcmp(modifier, "usecs") == 0) 2327 *flags |= HIST_FIELD_FL_TIMESTAMP_USECS; 2328 else if (strncmp(modifier, "bucket", 6) == 0) { 2329 int ret; 2330 2331 modifier += 6; 2332 2333 if (*modifier == 's') 2334 modifier++; 2335 if (*modifier != '=') 2336 goto error; 2337 modifier++; 2338 ret = kstrtoul(modifier, 0, buckets); 2339 if (ret || !(*buckets)) 2340 goto error; 2341 *flags |= HIST_FIELD_FL_BUCKET; 2342 } else if (strncmp(modifier, "percent", 7) == 0) { 2343 if (*flags & (HIST_FIELD_FL_VAR | HIST_FIELD_FL_KEY)) 2344 goto error; 2345 *flags |= HIST_FIELD_FL_PERCENT; 2346 } else if (strncmp(modifier, "graph", 5) == 0) { 2347 if (*flags & (HIST_FIELD_FL_VAR | HIST_FIELD_FL_KEY)) 2348 goto error; 2349 *flags |= HIST_FIELD_FL_GRAPH; 2350 } else { 2351 error: 2352 hist_err(tr, HIST_ERR_BAD_FIELD_MODIFIER, errpos(modifier)); 2353 field = ERR_PTR(-EINVAL); 2354 goto out; 2355 } 2356 } 2357 2358 if (strcmp(field_name, "common_timestamp") == 0) { 2359 *flags |= HIST_FIELD_FL_TIMESTAMP; 2360 hist_data->enable_timestamps = true; 2361 if (*flags & HIST_FIELD_FL_TIMESTAMP_USECS) 2362 hist_data->attrs->ts_in_usecs = true; 2363 } else if (strcmp(field_name, "common_stacktrace") == 0) { 2364 *flags |= HIST_FIELD_FL_STACKTRACE; 2365 } else if (strcmp(field_name, "common_cpu") == 0) 2366 *flags |= HIST_FIELD_FL_CPU; 2367 else if (strcmp(field_name, "hitcount") == 0) 2368 *flags |= HIST_FIELD_FL_HITCOUNT; 2369 else { 2370 field = trace_find_event_field(file->event_call, field_name); 2371 if (!field || !field->size) { 2372 /* 2373 * For backward compatibility, if field_name 2374 * was "cpu" or "stacktrace", then we treat this 2375 * the same as common_cpu and common_stacktrace 2376 * respectively. This also works for "CPU", and 2377 * "STACKTRACE". 2378 */ 2379 if (field && field->filter_type == FILTER_CPU) { 2380 *flags |= HIST_FIELD_FL_CPU; 2381 } else if (field && field->filter_type == FILTER_STACKTRACE) { 2382 *flags |= HIST_FIELD_FL_STACKTRACE; 2383 } else { 2384 hist_err(tr, HIST_ERR_FIELD_NOT_FOUND, 2385 errpos(field_name)); 2386 field = ERR_PTR(-EINVAL); 2387 goto out; 2388 } 2389 } 2390 } 2391 out: 2392 kfree(str); 2393 2394 return field; 2395 } 2396 2397 static struct hist_field *create_alias(struct hist_trigger_data *hist_data, 2398 struct hist_field *var_ref, 2399 char *var_name) 2400 { 2401 struct hist_field *alias = NULL; 2402 unsigned long flags = HIST_FIELD_FL_ALIAS | HIST_FIELD_FL_VAR; 2403 2404 alias = create_hist_field(hist_data, NULL, flags, var_name); 2405 if (!alias) 2406 return NULL; 2407 2408 alias->fn_num = var_ref->fn_num; 2409 alias->operands[0] = var_ref; 2410 2411 if (init_var_ref(alias, var_ref, var_ref->system, var_ref->event_name)) { 2412 destroy_hist_field(alias, 0); 2413 return NULL; 2414 } 2415 2416 alias->var_ref_idx = var_ref->var_ref_idx; 2417 2418 return alias; 2419 } 2420 2421 static struct hist_field *parse_const(struct hist_trigger_data *hist_data, 2422 char *str, char *var_name, 2423 unsigned long *flags) 2424 { 2425 struct trace_array *tr = hist_data->event_file->tr; 2426 struct hist_field *field = NULL; 2427 u64 constant; 2428 2429 if (kstrtoull(str, 0, &constant)) { 2430 hist_err(tr, HIST_ERR_EXPECT_NUMBER, errpos(str)); 2431 return NULL; 2432 } 2433 2434 *flags |= HIST_FIELD_FL_CONST; 2435 field = create_hist_field(hist_data, NULL, *flags, var_name); 2436 if (!field) 2437 return NULL; 2438 2439 field->constant = constant; 2440 2441 return field; 2442 } 2443 2444 static struct hist_field *parse_atom(struct hist_trigger_data *hist_data, 2445 struct trace_event_file *file, char *str, 2446 unsigned long *flags, char *var_name) 2447 { 2448 char *s, *ref_system = NULL, *ref_event = NULL, *ref_var = str; 2449 struct ftrace_event_field *field = NULL; 2450 struct hist_field *hist_field = NULL; 2451 unsigned long buckets = 0; 2452 int ret = 0; 2453 2454 if (isdigit(str[0])) { 2455 hist_field = parse_const(hist_data, str, var_name, flags); 2456 if (!hist_field) { 2457 ret = -EINVAL; 2458 goto out; 2459 } 2460 return hist_field; 2461 } 2462 2463 s = strchr(str, '.'); 2464 if (s) { 2465 s = strchr(++s, '.'); 2466 if (s) { 2467 ref_system = strsep(&str, "."); 2468 if (!str) { 2469 ret = -EINVAL; 2470 goto out; 2471 } 2472 ref_event = strsep(&str, "."); 2473 if (!str) { 2474 ret = -EINVAL; 2475 goto out; 2476 } 2477 ref_var = str; 2478 } 2479 } 2480 2481 s = local_field_var_ref(hist_data, ref_system, ref_event, ref_var); 2482 if (!s) { 2483 hist_field = parse_var_ref(hist_data, ref_system, 2484 ref_event, ref_var); 2485 if (hist_field) { 2486 if (var_name) { 2487 hist_field = create_alias(hist_data, hist_field, var_name); 2488 if (!hist_field) { 2489 ret = -ENOMEM; 2490 goto out; 2491 } 2492 } 2493 return hist_field; 2494 } 2495 } else 2496 str = s; 2497 2498 field = parse_field(hist_data, file, str, flags, &buckets); 2499 if (IS_ERR(field)) { 2500 ret = PTR_ERR(field); 2501 goto out; 2502 } 2503 2504 hist_field = create_hist_field(hist_data, field, *flags, var_name); 2505 if (!hist_field) { 2506 ret = -ENOMEM; 2507 goto out; 2508 } 2509 hist_field->buckets = buckets; 2510 2511 return hist_field; 2512 out: 2513 return ERR_PTR(ret); 2514 } 2515 2516 static struct hist_field *parse_expr(struct hist_trigger_data *hist_data, 2517 struct trace_event_file *file, 2518 char *str, unsigned long flags, 2519 char *var_name, unsigned int *n_subexprs); 2520 2521 static struct hist_field *parse_unary(struct hist_trigger_data *hist_data, 2522 struct trace_event_file *file, 2523 char *str, unsigned long flags, 2524 char *var_name, unsigned int *n_subexprs) 2525 { 2526 struct hist_field *operand1, *expr = NULL; 2527 unsigned long operand_flags; 2528 int ret = 0; 2529 char *s; 2530 2531 /* Unary minus operator, increment n_subexprs */ 2532 ++*n_subexprs; 2533 2534 /* we support only -(xxx) i.e. explicit parens required */ 2535 2536 if (*n_subexprs > 3) { 2537 hist_err(file->tr, HIST_ERR_TOO_MANY_SUBEXPR, errpos(str)); 2538 ret = -EINVAL; 2539 goto free; 2540 } 2541 2542 str++; /* skip leading '-' */ 2543 2544 s = strchr(str, '('); 2545 if (s) 2546 str++; 2547 else { 2548 ret = -EINVAL; 2549 goto free; 2550 } 2551 2552 s = strrchr(str, ')'); 2553 if (s) { 2554 /* unary minus not supported in sub-expressions */ 2555 if (*(s+1) != '\0') { 2556 hist_err(file->tr, HIST_ERR_UNARY_MINUS_SUBEXPR, 2557 errpos(str)); 2558 ret = -EINVAL; 2559 goto free; 2560 } 2561 *s = '\0'; 2562 } 2563 else { 2564 ret = -EINVAL; /* no closing ')' */ 2565 goto free; 2566 } 2567 2568 flags |= HIST_FIELD_FL_EXPR; 2569 expr = create_hist_field(hist_data, NULL, flags, var_name); 2570 if (!expr) { 2571 ret = -ENOMEM; 2572 goto free; 2573 } 2574 2575 operand_flags = 0; 2576 operand1 = parse_expr(hist_data, file, str, operand_flags, NULL, n_subexprs); 2577 if (IS_ERR(operand1)) { 2578 ret = PTR_ERR(operand1); 2579 goto free; 2580 } 2581 if (operand1->flags & HIST_FIELD_FL_STRING) { 2582 /* String type can not be the operand of unary operator. */ 2583 hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(str)); 2584 destroy_hist_field(operand1, 0); 2585 ret = -EINVAL; 2586 goto free; 2587 } 2588 2589 expr->flags |= operand1->flags & 2590 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS); 2591 expr->fn_num = HIST_FIELD_FN_UMINUS; 2592 expr->operands[0] = operand1; 2593 expr->size = operand1->size; 2594 expr->is_signed = operand1->is_signed; 2595 expr->operator = FIELD_OP_UNARY_MINUS; 2596 expr->name = expr_str(expr, 0); 2597 expr->type = kstrdup_const(operand1->type, GFP_KERNEL); 2598 if (!expr->type) { 2599 ret = -ENOMEM; 2600 goto free; 2601 } 2602 2603 return expr; 2604 free: 2605 destroy_hist_field(expr, 0); 2606 return ERR_PTR(ret); 2607 } 2608 2609 /* 2610 * If the operands are var refs, return pointers the 2611 * variable(s) referenced in var1 and var2, else NULL. 2612 */ 2613 static int check_expr_operands(struct trace_array *tr, 2614 struct hist_field *operand1, 2615 struct hist_field *operand2, 2616 struct hist_field **var1, 2617 struct hist_field **var2) 2618 { 2619 unsigned long operand1_flags = operand1->flags; 2620 unsigned long operand2_flags = operand2->flags; 2621 2622 if ((operand1_flags & HIST_FIELD_FL_VAR_REF) || 2623 (operand1_flags & HIST_FIELD_FL_ALIAS)) { 2624 struct hist_field *var; 2625 2626 var = find_var_field(operand1->var.hist_data, operand1->name); 2627 if (!var) 2628 return -EINVAL; 2629 operand1_flags = var->flags; 2630 *var1 = var; 2631 } 2632 2633 if ((operand2_flags & HIST_FIELD_FL_VAR_REF) || 2634 (operand2_flags & HIST_FIELD_FL_ALIAS)) { 2635 struct hist_field *var; 2636 2637 var = find_var_field(operand2->var.hist_data, operand2->name); 2638 if (!var) 2639 return -EINVAL; 2640 operand2_flags = var->flags; 2641 *var2 = var; 2642 } 2643 2644 if ((operand1_flags & HIST_FIELD_FL_TIMESTAMP_USECS) != 2645 (operand2_flags & HIST_FIELD_FL_TIMESTAMP_USECS)) { 2646 hist_err(tr, HIST_ERR_TIMESTAMP_MISMATCH, 0); 2647 return -EINVAL; 2648 } 2649 2650 return 0; 2651 } 2652 2653 static struct hist_field *parse_expr(struct hist_trigger_data *hist_data, 2654 struct trace_event_file *file, 2655 char *str, unsigned long flags, 2656 char *var_name, unsigned int *n_subexprs) 2657 { 2658 struct hist_field *operand1 = NULL, *operand2 = NULL, *expr = NULL; 2659 struct hist_field *var1 = NULL, *var2 = NULL; 2660 unsigned long operand_flags, operand2_flags; 2661 int field_op, ret = -EINVAL; 2662 char *sep, *operand1_str; 2663 enum hist_field_fn op_fn; 2664 bool combine_consts; 2665 2666 if (*n_subexprs > 3) { 2667 hist_err(file->tr, HIST_ERR_TOO_MANY_SUBEXPR, errpos(str)); 2668 return ERR_PTR(-EINVAL); 2669 } 2670 2671 field_op = contains_operator(str, &sep); 2672 2673 if (field_op == FIELD_OP_NONE) 2674 return parse_atom(hist_data, file, str, &flags, var_name); 2675 2676 if (field_op == FIELD_OP_UNARY_MINUS) 2677 return parse_unary(hist_data, file, str, flags, var_name, n_subexprs); 2678 2679 /* Binary operator found, increment n_subexprs */ 2680 ++*n_subexprs; 2681 2682 /* Split the expression string at the root operator */ 2683 if (!sep) 2684 return ERR_PTR(-EINVAL); 2685 2686 *sep = '\0'; 2687 operand1_str = str; 2688 str = sep+1; 2689 2690 /* Binary operator requires both operands */ 2691 if (*operand1_str == '\0' || *str == '\0') 2692 return ERR_PTR(-EINVAL); 2693 2694 operand_flags = 0; 2695 2696 /* LHS of string is an expression e.g. a+b in a+b+c */ 2697 operand1 = parse_expr(hist_data, file, operand1_str, operand_flags, NULL, n_subexprs); 2698 if (IS_ERR(operand1)) 2699 return ERR_CAST(operand1); 2700 2701 if (operand1->flags & HIST_FIELD_FL_STRING) { 2702 hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(operand1_str)); 2703 ret = -EINVAL; 2704 goto free_op1; 2705 } 2706 2707 /* RHS of string is another expression e.g. c in a+b+c */ 2708 operand_flags = 0; 2709 operand2 = parse_expr(hist_data, file, str, operand_flags, NULL, n_subexprs); 2710 if (IS_ERR(operand2)) { 2711 ret = PTR_ERR(operand2); 2712 goto free_op1; 2713 } 2714 if (operand2->flags & HIST_FIELD_FL_STRING) { 2715 hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(str)); 2716 ret = -EINVAL; 2717 goto free_operands; 2718 } 2719 2720 switch (field_op) { 2721 case FIELD_OP_MINUS: 2722 op_fn = HIST_FIELD_FN_MINUS; 2723 break; 2724 case FIELD_OP_PLUS: 2725 op_fn = HIST_FIELD_FN_PLUS; 2726 break; 2727 case FIELD_OP_DIV: 2728 op_fn = HIST_FIELD_FN_DIV; 2729 break; 2730 case FIELD_OP_MULT: 2731 op_fn = HIST_FIELD_FN_MULT; 2732 break; 2733 default: 2734 ret = -EINVAL; 2735 goto free_operands; 2736 } 2737 2738 ret = check_expr_operands(file->tr, operand1, operand2, &var1, &var2); 2739 if (ret) 2740 goto free_operands; 2741 2742 operand_flags = var1 ? var1->flags : operand1->flags; 2743 operand2_flags = var2 ? var2->flags : operand2->flags; 2744 2745 /* 2746 * If both operands are constant, the expression can be 2747 * collapsed to a single constant. 2748 */ 2749 combine_consts = operand_flags & operand2_flags & HIST_FIELD_FL_CONST; 2750 2751 flags |= combine_consts ? HIST_FIELD_FL_CONST : HIST_FIELD_FL_EXPR; 2752 2753 flags |= operand1->flags & 2754 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS); 2755 2756 expr = create_hist_field(hist_data, NULL, flags, var_name); 2757 if (!expr) { 2758 ret = -ENOMEM; 2759 goto free_operands; 2760 } 2761 2762 operand1->read_once = true; 2763 operand2->read_once = true; 2764 2765 /* The operands are now owned and free'd by 'expr' */ 2766 expr->operands[0] = operand1; 2767 expr->operands[1] = operand2; 2768 2769 if (field_op == FIELD_OP_DIV && 2770 operand2_flags & HIST_FIELD_FL_CONST) { 2771 u64 divisor = var2 ? var2->constant : operand2->constant; 2772 2773 if (!divisor) { 2774 hist_err(file->tr, HIST_ERR_DIVISION_BY_ZERO, errpos(str)); 2775 ret = -EDOM; 2776 goto free_expr; 2777 } 2778 2779 /* 2780 * Copy the divisor here so we don't have to look it up 2781 * later if this is a var ref 2782 */ 2783 operand2->constant = divisor; 2784 op_fn = hist_field_get_div_fn(operand2); 2785 } 2786 2787 expr->fn_num = op_fn; 2788 2789 if (combine_consts) { 2790 if (var1) 2791 expr->operands[0] = var1; 2792 if (var2) 2793 expr->operands[1] = var2; 2794 2795 expr->constant = hist_fn_call(expr, NULL, NULL, NULL, NULL); 2796 expr->fn_num = HIST_FIELD_FN_CONST; 2797 2798 expr->operands[0] = NULL; 2799 expr->operands[1] = NULL; 2800 2801 /* 2802 * var refs won't be destroyed immediately 2803 * See: destroy_hist_field() 2804 */ 2805 destroy_hist_field(operand2, 0); 2806 destroy_hist_field(operand1, 0); 2807 2808 expr->name = expr_str(expr, 0); 2809 } else { 2810 /* The operand sizes should be the same, so just pick one */ 2811 expr->size = operand1->size; 2812 expr->is_signed = operand1->is_signed; 2813 2814 expr->operator = field_op; 2815 expr->type = kstrdup_const(operand1->type, GFP_KERNEL); 2816 if (!expr->type) { 2817 ret = -ENOMEM; 2818 goto free_expr; 2819 } 2820 2821 expr->name = expr_str(expr, 0); 2822 } 2823 2824 return expr; 2825 2826 free_operands: 2827 destroy_hist_field(operand2, 0); 2828 free_op1: 2829 destroy_hist_field(operand1, 0); 2830 return ERR_PTR(ret); 2831 2832 free_expr: 2833 destroy_hist_field(expr, 0); 2834 return ERR_PTR(ret); 2835 } 2836 2837 static char *find_trigger_filter(struct hist_trigger_data *hist_data, 2838 struct trace_event_file *file) 2839 { 2840 struct event_trigger_data *test; 2841 2842 lockdep_assert_held(&event_mutex); 2843 2844 list_for_each_entry(test, &file->triggers, list) { 2845 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 2846 if (test->private_data == hist_data) 2847 return test->filter_str; 2848 } 2849 } 2850 2851 return NULL; 2852 } 2853 2854 static struct event_command trigger_hist_cmd; 2855 static int event_hist_trigger_parse(struct event_command *cmd_ops, 2856 struct trace_event_file *file, 2857 char *glob, char *cmd, 2858 char *param_and_filter); 2859 2860 static bool compatible_keys(struct hist_trigger_data *target_hist_data, 2861 struct hist_trigger_data *hist_data, 2862 unsigned int n_keys) 2863 { 2864 struct hist_field *target_hist_field, *hist_field; 2865 unsigned int n, i, j; 2866 2867 if (hist_data->n_fields - hist_data->n_vals != n_keys) 2868 return false; 2869 2870 i = hist_data->n_vals; 2871 j = target_hist_data->n_vals; 2872 2873 for (n = 0; n < n_keys; n++) { 2874 hist_field = hist_data->fields[i + n]; 2875 target_hist_field = target_hist_data->fields[j + n]; 2876 2877 if (strcmp(hist_field->type, target_hist_field->type) != 0) 2878 return false; 2879 if (hist_field->size != target_hist_field->size) 2880 return false; 2881 if (hist_field->is_signed != target_hist_field->is_signed) 2882 return false; 2883 } 2884 2885 return true; 2886 } 2887 2888 static struct hist_trigger_data * 2889 find_compatible_hist(struct hist_trigger_data *target_hist_data, 2890 struct trace_event_file *file) 2891 { 2892 struct hist_trigger_data *hist_data; 2893 struct event_trigger_data *test; 2894 unsigned int n_keys; 2895 2896 lockdep_assert_held(&event_mutex); 2897 2898 n_keys = target_hist_data->n_fields - target_hist_data->n_vals; 2899 2900 list_for_each_entry(test, &file->triggers, list) { 2901 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 2902 hist_data = test->private_data; 2903 2904 if (compatible_keys(target_hist_data, hist_data, n_keys)) 2905 return hist_data; 2906 } 2907 } 2908 2909 return NULL; 2910 } 2911 2912 static struct trace_event_file *event_file(struct trace_array *tr, 2913 char *system, char *event_name) 2914 { 2915 struct trace_event_file *file; 2916 2917 file = __find_event_file(tr, system, event_name); 2918 if (!file) 2919 return ERR_PTR(-EINVAL); 2920 2921 return file; 2922 } 2923 2924 static struct hist_field * 2925 find_synthetic_field_var(struct hist_trigger_data *target_hist_data, 2926 char *system, char *event_name, char *field_name) 2927 { 2928 struct hist_field *event_var; 2929 char *synthetic_name; 2930 2931 synthetic_name = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL); 2932 if (!synthetic_name) 2933 return ERR_PTR(-ENOMEM); 2934 2935 strcpy(synthetic_name, "synthetic_"); 2936 strcat(synthetic_name, field_name); 2937 2938 event_var = find_event_var(target_hist_data, system, event_name, synthetic_name); 2939 2940 kfree(synthetic_name); 2941 2942 return event_var; 2943 } 2944 2945 /** 2946 * create_field_var_hist - Automatically create a histogram and var for a field 2947 * @target_hist_data: The target hist trigger 2948 * @subsys_name: Optional subsystem name 2949 * @event_name: Optional event name 2950 * @field_name: The name of the field (and the resulting variable) 2951 * 2952 * Hist trigger actions fetch data from variables, not directly from 2953 * events. However, for convenience, users are allowed to directly 2954 * specify an event field in an action, which will be automatically 2955 * converted into a variable on their behalf. 2956 * 2957 * If a user specifies a field on an event that isn't the event the 2958 * histogram currently being defined (the target event histogram), the 2959 * only way that can be accomplished is if a new hist trigger is 2960 * created and the field variable defined on that. 2961 * 2962 * This function creates a new histogram compatible with the target 2963 * event (meaning a histogram with the same key as the target 2964 * histogram), and creates a variable for the specified field, but 2965 * with 'synthetic_' prepended to the variable name in order to avoid 2966 * collision with normal field variables. 2967 * 2968 * Return: The variable created for the field. 2969 */ 2970 static struct hist_field * 2971 create_field_var_hist(struct hist_trigger_data *target_hist_data, 2972 char *subsys_name, char *event_name, char *field_name) 2973 { 2974 struct trace_array *tr = target_hist_data->event_file->tr; 2975 struct hist_trigger_data *hist_data; 2976 unsigned int i, n, first = true; 2977 struct field_var_hist *var_hist; 2978 struct trace_event_file *file; 2979 struct hist_field *key_field; 2980 struct hist_field *event_var; 2981 char *saved_filter; 2982 char *cmd; 2983 int ret; 2984 2985 if (target_hist_data->n_field_var_hists >= SYNTH_FIELDS_MAX) { 2986 hist_err(tr, HIST_ERR_TOO_MANY_FIELD_VARS, errpos(field_name)); 2987 return ERR_PTR(-EINVAL); 2988 } 2989 2990 file = event_file(tr, subsys_name, event_name); 2991 2992 if (IS_ERR(file)) { 2993 hist_err(tr, HIST_ERR_EVENT_FILE_NOT_FOUND, errpos(field_name)); 2994 ret = PTR_ERR(file); 2995 return ERR_PTR(ret); 2996 } 2997 2998 /* 2999 * Look for a histogram compatible with target. We'll use the 3000 * found histogram specification to create a new matching 3001 * histogram with our variable on it. target_hist_data is not 3002 * yet a registered histogram so we can't use that. 3003 */ 3004 hist_data = find_compatible_hist(target_hist_data, file); 3005 if (!hist_data) { 3006 hist_err(tr, HIST_ERR_HIST_NOT_FOUND, errpos(field_name)); 3007 return ERR_PTR(-EINVAL); 3008 } 3009 3010 /* See if a synthetic field variable has already been created */ 3011 event_var = find_synthetic_field_var(target_hist_data, subsys_name, 3012 event_name, field_name); 3013 if (!IS_ERR_OR_NULL(event_var)) 3014 return event_var; 3015 3016 var_hist = kzalloc(sizeof(*var_hist), GFP_KERNEL); 3017 if (!var_hist) 3018 return ERR_PTR(-ENOMEM); 3019 3020 cmd = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL); 3021 if (!cmd) { 3022 kfree(var_hist); 3023 return ERR_PTR(-ENOMEM); 3024 } 3025 3026 /* Use the same keys as the compatible histogram */ 3027 strcat(cmd, "keys="); 3028 3029 for_each_hist_key_field(i, hist_data) { 3030 key_field = hist_data->fields[i]; 3031 if (!first) 3032 strcat(cmd, ","); 3033 strcat(cmd, key_field->field->name); 3034 first = false; 3035 } 3036 3037 /* Create the synthetic field variable specification */ 3038 strcat(cmd, ":synthetic_"); 3039 strcat(cmd, field_name); 3040 strcat(cmd, "="); 3041 strcat(cmd, field_name); 3042 3043 /* Use the same filter as the compatible histogram */ 3044 saved_filter = find_trigger_filter(hist_data, file); 3045 if (saved_filter) { 3046 strcat(cmd, " if "); 3047 strcat(cmd, saved_filter); 3048 } 3049 3050 var_hist->cmd = kstrdup(cmd, GFP_KERNEL); 3051 if (!var_hist->cmd) { 3052 kfree(cmd); 3053 kfree(var_hist); 3054 return ERR_PTR(-ENOMEM); 3055 } 3056 3057 /* Save the compatible histogram information */ 3058 var_hist->hist_data = hist_data; 3059 3060 /* Create the new histogram with our variable */ 3061 ret = event_hist_trigger_parse(&trigger_hist_cmd, file, 3062 "", "hist", cmd); 3063 if (ret) { 3064 kfree(cmd); 3065 kfree(var_hist->cmd); 3066 kfree(var_hist); 3067 hist_err(tr, HIST_ERR_HIST_CREATE_FAIL, errpos(field_name)); 3068 return ERR_PTR(ret); 3069 } 3070 3071 kfree(cmd); 3072 3073 /* If we can't find the variable, something went wrong */ 3074 event_var = find_synthetic_field_var(target_hist_data, subsys_name, 3075 event_name, field_name); 3076 if (IS_ERR_OR_NULL(event_var)) { 3077 kfree(var_hist->cmd); 3078 kfree(var_hist); 3079 hist_err(tr, HIST_ERR_SYNTH_VAR_NOT_FOUND, errpos(field_name)); 3080 return ERR_PTR(-EINVAL); 3081 } 3082 3083 n = target_hist_data->n_field_var_hists; 3084 target_hist_data->field_var_hists[n] = var_hist; 3085 target_hist_data->n_field_var_hists++; 3086 3087 return event_var; 3088 } 3089 3090 static struct hist_field * 3091 find_target_event_var(struct hist_trigger_data *hist_data, 3092 char *subsys_name, char *event_name, char *var_name) 3093 { 3094 struct trace_event_file *file = hist_data->event_file; 3095 struct hist_field *hist_field = NULL; 3096 3097 if (subsys_name) { 3098 struct trace_event_call *call; 3099 3100 if (!event_name) 3101 return NULL; 3102 3103 call = file->event_call; 3104 3105 if (strcmp(subsys_name, call->class->system) != 0) 3106 return NULL; 3107 3108 if (strcmp(event_name, trace_event_name(call)) != 0) 3109 return NULL; 3110 } 3111 3112 hist_field = find_var_field(hist_data, var_name); 3113 3114 return hist_field; 3115 } 3116 3117 static inline void __update_field_vars(struct tracing_map_elt *elt, 3118 struct trace_buffer *buffer, 3119 struct ring_buffer_event *rbe, 3120 void *rec, 3121 struct field_var **field_vars, 3122 unsigned int n_field_vars, 3123 unsigned int field_var_str_start) 3124 { 3125 struct hist_elt_data *elt_data = elt->private_data; 3126 unsigned int i, j, var_idx; 3127 u64 var_val; 3128 3129 /* Make sure stacktrace can fit in the string variable length */ 3130 BUILD_BUG_ON((HIST_STACKTRACE_DEPTH + 1) * sizeof(long) >= STR_VAR_LEN_MAX); 3131 3132 for (i = 0, j = field_var_str_start; i < n_field_vars; i++) { 3133 struct field_var *field_var = field_vars[i]; 3134 struct hist_field *var = field_var->var; 3135 struct hist_field *val = field_var->val; 3136 3137 var_val = hist_fn_call(val, elt, buffer, rbe, rec); 3138 var_idx = var->var.idx; 3139 3140 if (val->flags & (HIST_FIELD_FL_STRING | 3141 HIST_FIELD_FL_STACKTRACE)) { 3142 char *str = elt_data->field_var_str[j++]; 3143 char *val_str = (char *)(uintptr_t)var_val; 3144 unsigned int size; 3145 3146 if (val->flags & HIST_FIELD_FL_STRING) { 3147 size = min(val->size, STR_VAR_LEN_MAX); 3148 strscpy(str, val_str, size); 3149 } else { 3150 char *stack_start = str + sizeof(unsigned long); 3151 int e; 3152 3153 e = stack_trace_save((void *)stack_start, 3154 HIST_STACKTRACE_DEPTH, 3155 HIST_STACKTRACE_SKIP); 3156 if (e < HIST_STACKTRACE_DEPTH - 1) 3157 ((unsigned long *)stack_start)[e] = 0; 3158 *((unsigned long *)str) = e; 3159 } 3160 var_val = (u64)(uintptr_t)str; 3161 } 3162 tracing_map_set_var(elt, var_idx, var_val); 3163 } 3164 } 3165 3166 static void update_field_vars(struct hist_trigger_data *hist_data, 3167 struct tracing_map_elt *elt, 3168 struct trace_buffer *buffer, 3169 struct ring_buffer_event *rbe, 3170 void *rec) 3171 { 3172 __update_field_vars(elt, buffer, rbe, rec, hist_data->field_vars, 3173 hist_data->n_field_vars, 0); 3174 } 3175 3176 static void save_track_data_vars(struct hist_trigger_data *hist_data, 3177 struct tracing_map_elt *elt, 3178 struct trace_buffer *buffer, void *rec, 3179 struct ring_buffer_event *rbe, void *key, 3180 struct action_data *data, u64 *var_ref_vals) 3181 { 3182 __update_field_vars(elt, buffer, rbe, rec, hist_data->save_vars, 3183 hist_data->n_save_vars, hist_data->n_field_var_str); 3184 } 3185 3186 static struct hist_field *create_var(struct hist_trigger_data *hist_data, 3187 struct trace_event_file *file, 3188 char *name, int size, const char *type) 3189 { 3190 struct hist_field *var; 3191 int idx; 3192 3193 if (find_var(hist_data, file, name) && !hist_data->remove) { 3194 var = ERR_PTR(-EINVAL); 3195 goto out; 3196 } 3197 3198 var = kzalloc(sizeof(struct hist_field), GFP_KERNEL); 3199 if (!var) { 3200 var = ERR_PTR(-ENOMEM); 3201 goto out; 3202 } 3203 3204 idx = tracing_map_add_var(hist_data->map); 3205 if (idx < 0) { 3206 kfree(var); 3207 var = ERR_PTR(-EINVAL); 3208 goto out; 3209 } 3210 3211 var->ref = 1; 3212 var->flags = HIST_FIELD_FL_VAR; 3213 var->var.idx = idx; 3214 var->var.hist_data = var->hist_data = hist_data; 3215 var->size = size; 3216 var->var.name = kstrdup(name, GFP_KERNEL); 3217 var->type = kstrdup_const(type, GFP_KERNEL); 3218 if (!var->var.name || !var->type) { 3219 kfree_const(var->type); 3220 kfree(var->var.name); 3221 kfree(var); 3222 var = ERR_PTR(-ENOMEM); 3223 } 3224 out: 3225 return var; 3226 } 3227 3228 static struct field_var *create_field_var(struct hist_trigger_data *hist_data, 3229 struct trace_event_file *file, 3230 char *field_name) 3231 { 3232 struct hist_field *val = NULL, *var = NULL; 3233 unsigned long flags = HIST_FIELD_FL_VAR; 3234 struct trace_array *tr = file->tr; 3235 struct field_var *field_var; 3236 int ret = 0; 3237 3238 if (hist_data->n_field_vars >= SYNTH_FIELDS_MAX) { 3239 hist_err(tr, HIST_ERR_TOO_MANY_FIELD_VARS, errpos(field_name)); 3240 ret = -EINVAL; 3241 goto err; 3242 } 3243 3244 val = parse_atom(hist_data, file, field_name, &flags, NULL); 3245 if (IS_ERR(val)) { 3246 hist_err(tr, HIST_ERR_FIELD_VAR_PARSE_FAIL, errpos(field_name)); 3247 ret = PTR_ERR(val); 3248 goto err; 3249 } 3250 3251 var = create_var(hist_data, file, field_name, val->size, val->type); 3252 if (IS_ERR(var)) { 3253 hist_err(tr, HIST_ERR_VAR_CREATE_FIND_FAIL, errpos(field_name)); 3254 kfree(val); 3255 ret = PTR_ERR(var); 3256 goto err; 3257 } 3258 3259 field_var = kzalloc(sizeof(struct field_var), GFP_KERNEL); 3260 if (!field_var) { 3261 kfree(val); 3262 kfree(var); 3263 ret = -ENOMEM; 3264 goto err; 3265 } 3266 3267 field_var->var = var; 3268 field_var->val = val; 3269 out: 3270 return field_var; 3271 err: 3272 field_var = ERR_PTR(ret); 3273 goto out; 3274 } 3275 3276 /** 3277 * create_target_field_var - Automatically create a variable for a field 3278 * @target_hist_data: The target hist trigger 3279 * @subsys_name: Optional subsystem name 3280 * @event_name: Optional event name 3281 * @var_name: The name of the field (and the resulting variable) 3282 * 3283 * Hist trigger actions fetch data from variables, not directly from 3284 * events. However, for convenience, users are allowed to directly 3285 * specify an event field in an action, which will be automatically 3286 * converted into a variable on their behalf. 3287 * 3288 * This function creates a field variable with the name var_name on 3289 * the hist trigger currently being defined on the target event. If 3290 * subsys_name and event_name are specified, this function simply 3291 * verifies that they do in fact match the target event subsystem and 3292 * event name. 3293 * 3294 * Return: The variable created for the field. 3295 */ 3296 static struct field_var * 3297 create_target_field_var(struct hist_trigger_data *target_hist_data, 3298 char *subsys_name, char *event_name, char *var_name) 3299 { 3300 struct trace_event_file *file = target_hist_data->event_file; 3301 3302 if (subsys_name) { 3303 struct trace_event_call *call; 3304 3305 if (!event_name) 3306 return NULL; 3307 3308 call = file->event_call; 3309 3310 if (strcmp(subsys_name, call->class->system) != 0) 3311 return NULL; 3312 3313 if (strcmp(event_name, trace_event_name(call)) != 0) 3314 return NULL; 3315 } 3316 3317 return create_field_var(target_hist_data, file, var_name); 3318 } 3319 3320 static bool check_track_val_max(u64 track_val, u64 var_val) 3321 { 3322 if (var_val <= track_val) 3323 return false; 3324 3325 return true; 3326 } 3327 3328 static bool check_track_val_changed(u64 track_val, u64 var_val) 3329 { 3330 if (var_val == track_val) 3331 return false; 3332 3333 return true; 3334 } 3335 3336 static u64 get_track_val(struct hist_trigger_data *hist_data, 3337 struct tracing_map_elt *elt, 3338 struct action_data *data) 3339 { 3340 unsigned int track_var_idx = data->track_data.track_var->var.idx; 3341 u64 track_val; 3342 3343 track_val = tracing_map_read_var(elt, track_var_idx); 3344 3345 return track_val; 3346 } 3347 3348 static void save_track_val(struct hist_trigger_data *hist_data, 3349 struct tracing_map_elt *elt, 3350 struct action_data *data, u64 var_val) 3351 { 3352 unsigned int track_var_idx = data->track_data.track_var->var.idx; 3353 3354 tracing_map_set_var(elt, track_var_idx, var_val); 3355 } 3356 3357 static void save_track_data(struct hist_trigger_data *hist_data, 3358 struct tracing_map_elt *elt, 3359 struct trace_buffer *buffer, void *rec, 3360 struct ring_buffer_event *rbe, void *key, 3361 struct action_data *data, u64 *var_ref_vals) 3362 { 3363 if (data->track_data.save_data) 3364 data->track_data.save_data(hist_data, elt, buffer, rec, rbe, 3365 key, data, var_ref_vals); 3366 } 3367 3368 static bool check_track_val(struct tracing_map_elt *elt, 3369 struct action_data *data, 3370 u64 var_val) 3371 { 3372 struct hist_trigger_data *hist_data; 3373 u64 track_val; 3374 3375 hist_data = data->track_data.track_var->hist_data; 3376 track_val = get_track_val(hist_data, elt, data); 3377 3378 return data->track_data.check_val(track_val, var_val); 3379 } 3380 3381 #ifdef CONFIG_TRACER_SNAPSHOT 3382 static bool cond_snapshot_update(struct trace_array *tr, void *cond_data) 3383 { 3384 /* called with tr->max_lock held */ 3385 struct track_data *track_data = tr->cond_snapshot->cond_data; 3386 struct hist_elt_data *elt_data, *track_elt_data; 3387 struct snapshot_context *context = cond_data; 3388 struct action_data *action; 3389 u64 track_val; 3390 3391 if (!track_data) 3392 return false; 3393 3394 action = track_data->action_data; 3395 3396 track_val = get_track_val(track_data->hist_data, context->elt, 3397 track_data->action_data); 3398 3399 if (!action->track_data.check_val(track_data->track_val, track_val)) 3400 return false; 3401 3402 track_data->track_val = track_val; 3403 memcpy(track_data->key, context->key, track_data->key_len); 3404 3405 elt_data = context->elt->private_data; 3406 track_elt_data = track_data->elt.private_data; 3407 if (elt_data->comm) 3408 strncpy(track_elt_data->comm, elt_data->comm, TASK_COMM_LEN); 3409 3410 track_data->updated = true; 3411 3412 return true; 3413 } 3414 3415 static void save_track_data_snapshot(struct hist_trigger_data *hist_data, 3416 struct tracing_map_elt *elt, 3417 struct trace_buffer *buffer, void *rec, 3418 struct ring_buffer_event *rbe, void *key, 3419 struct action_data *data, 3420 u64 *var_ref_vals) 3421 { 3422 struct trace_event_file *file = hist_data->event_file; 3423 struct snapshot_context context; 3424 3425 context.elt = elt; 3426 context.key = key; 3427 3428 tracing_snapshot_cond(file->tr, &context); 3429 } 3430 3431 static void hist_trigger_print_key(struct seq_file *m, 3432 struct hist_trigger_data *hist_data, 3433 void *key, 3434 struct tracing_map_elt *elt); 3435 3436 static struct action_data *snapshot_action(struct hist_trigger_data *hist_data) 3437 { 3438 unsigned int i; 3439 3440 if (!hist_data->n_actions) 3441 return NULL; 3442 3443 for (i = 0; i < hist_data->n_actions; i++) { 3444 struct action_data *data = hist_data->actions[i]; 3445 3446 if (data->action == ACTION_SNAPSHOT) 3447 return data; 3448 } 3449 3450 return NULL; 3451 } 3452 3453 static void track_data_snapshot_print(struct seq_file *m, 3454 struct hist_trigger_data *hist_data) 3455 { 3456 struct trace_event_file *file = hist_data->event_file; 3457 struct track_data *track_data; 3458 struct action_data *action; 3459 3460 track_data = tracing_cond_snapshot_data(file->tr); 3461 if (!track_data) 3462 return; 3463 3464 if (!track_data->updated) 3465 return; 3466 3467 action = snapshot_action(hist_data); 3468 if (!action) 3469 return; 3470 3471 seq_puts(m, "\nSnapshot taken (see tracing/snapshot). Details:\n"); 3472 seq_printf(m, "\ttriggering value { %s(%s) }: %10llu", 3473 action->handler == HANDLER_ONMAX ? "onmax" : "onchange", 3474 action->track_data.var_str, track_data->track_val); 3475 3476 seq_puts(m, "\ttriggered by event with key: "); 3477 hist_trigger_print_key(m, hist_data, track_data->key, &track_data->elt); 3478 seq_putc(m, '\n'); 3479 } 3480 #else 3481 static bool cond_snapshot_update(struct trace_array *tr, void *cond_data) 3482 { 3483 return false; 3484 } 3485 static void save_track_data_snapshot(struct hist_trigger_data *hist_data, 3486 struct tracing_map_elt *elt, 3487 struct trace_buffer *buffer, void *rec, 3488 struct ring_buffer_event *rbe, void *key, 3489 struct action_data *data, 3490 u64 *var_ref_vals) {} 3491 static void track_data_snapshot_print(struct seq_file *m, 3492 struct hist_trigger_data *hist_data) {} 3493 #endif /* CONFIG_TRACER_SNAPSHOT */ 3494 3495 static void track_data_print(struct seq_file *m, 3496 struct hist_trigger_data *hist_data, 3497 struct tracing_map_elt *elt, 3498 struct action_data *data) 3499 { 3500 u64 track_val = get_track_val(hist_data, elt, data); 3501 unsigned int i, save_var_idx; 3502 3503 if (data->handler == HANDLER_ONMAX) 3504 seq_printf(m, "\n\tmax: %10llu", track_val); 3505 else if (data->handler == HANDLER_ONCHANGE) 3506 seq_printf(m, "\n\tchanged: %10llu", track_val); 3507 3508 if (data->action == ACTION_SNAPSHOT) 3509 return; 3510 3511 for (i = 0; i < hist_data->n_save_vars; i++) { 3512 struct hist_field *save_val = hist_data->save_vars[i]->val; 3513 struct hist_field *save_var = hist_data->save_vars[i]->var; 3514 u64 val; 3515 3516 save_var_idx = save_var->var.idx; 3517 3518 val = tracing_map_read_var(elt, save_var_idx); 3519 3520 if (save_val->flags & HIST_FIELD_FL_STRING) { 3521 seq_printf(m, " %s: %-32s", save_var->var.name, 3522 (char *)(uintptr_t)(val)); 3523 } else 3524 seq_printf(m, " %s: %10llu", save_var->var.name, val); 3525 } 3526 } 3527 3528 static void ontrack_action(struct hist_trigger_data *hist_data, 3529 struct tracing_map_elt *elt, 3530 struct trace_buffer *buffer, void *rec, 3531 struct ring_buffer_event *rbe, void *key, 3532 struct action_data *data, u64 *var_ref_vals) 3533 { 3534 u64 var_val = var_ref_vals[data->track_data.var_ref->var_ref_idx]; 3535 3536 if (check_track_val(elt, data, var_val)) { 3537 save_track_val(hist_data, elt, data, var_val); 3538 save_track_data(hist_data, elt, buffer, rec, rbe, 3539 key, data, var_ref_vals); 3540 } 3541 } 3542 3543 static void action_data_destroy(struct action_data *data) 3544 { 3545 unsigned int i; 3546 3547 lockdep_assert_held(&event_mutex); 3548 3549 kfree(data->action_name); 3550 3551 for (i = 0; i < data->n_params; i++) 3552 kfree(data->params[i]); 3553 3554 if (data->synth_event) 3555 data->synth_event->ref--; 3556 3557 kfree(data->synth_event_name); 3558 3559 kfree(data); 3560 } 3561 3562 static void track_data_destroy(struct hist_trigger_data *hist_data, 3563 struct action_data *data) 3564 { 3565 struct trace_event_file *file = hist_data->event_file; 3566 3567 destroy_hist_field(data->track_data.track_var, 0); 3568 3569 if (data->action == ACTION_SNAPSHOT) { 3570 struct track_data *track_data; 3571 3572 track_data = tracing_cond_snapshot_data(file->tr); 3573 if (track_data && track_data->hist_data == hist_data) { 3574 tracing_snapshot_cond_disable(file->tr); 3575 track_data_free(track_data); 3576 } 3577 } 3578 3579 kfree(data->track_data.var_str); 3580 3581 action_data_destroy(data); 3582 } 3583 3584 static int action_create(struct hist_trigger_data *hist_data, 3585 struct action_data *data); 3586 3587 static int track_data_create(struct hist_trigger_data *hist_data, 3588 struct action_data *data) 3589 { 3590 struct hist_field *var_field, *ref_field, *track_var = NULL; 3591 struct trace_event_file *file = hist_data->event_file; 3592 struct trace_array *tr = file->tr; 3593 char *track_data_var_str; 3594 int ret = 0; 3595 3596 track_data_var_str = data->track_data.var_str; 3597 if (track_data_var_str[0] != '$') { 3598 hist_err(tr, HIST_ERR_ONX_NOT_VAR, errpos(track_data_var_str)); 3599 return -EINVAL; 3600 } 3601 track_data_var_str++; 3602 3603 var_field = find_target_event_var(hist_data, NULL, NULL, track_data_var_str); 3604 if (!var_field) { 3605 hist_err(tr, HIST_ERR_ONX_VAR_NOT_FOUND, errpos(track_data_var_str)); 3606 return -EINVAL; 3607 } 3608 3609 ref_field = create_var_ref(hist_data, var_field, NULL, NULL); 3610 if (!ref_field) 3611 return -ENOMEM; 3612 3613 data->track_data.var_ref = ref_field; 3614 3615 if (data->handler == HANDLER_ONMAX) 3616 track_var = create_var(hist_data, file, "__max", sizeof(u64), "u64"); 3617 if (IS_ERR(track_var)) { 3618 hist_err(tr, HIST_ERR_ONX_VAR_CREATE_FAIL, 0); 3619 ret = PTR_ERR(track_var); 3620 goto out; 3621 } 3622 3623 if (data->handler == HANDLER_ONCHANGE) 3624 track_var = create_var(hist_data, file, "__change", sizeof(u64), "u64"); 3625 if (IS_ERR(track_var)) { 3626 hist_err(tr, HIST_ERR_ONX_VAR_CREATE_FAIL, 0); 3627 ret = PTR_ERR(track_var); 3628 goto out; 3629 } 3630 data->track_data.track_var = track_var; 3631 3632 ret = action_create(hist_data, data); 3633 out: 3634 return ret; 3635 } 3636 3637 static int parse_action_params(struct trace_array *tr, char *params, 3638 struct action_data *data) 3639 { 3640 char *param, *saved_param; 3641 bool first_param = true; 3642 int ret = 0; 3643 3644 while (params) { 3645 if (data->n_params >= SYNTH_FIELDS_MAX) { 3646 hist_err(tr, HIST_ERR_TOO_MANY_PARAMS, 0); 3647 ret = -EINVAL; 3648 goto out; 3649 } 3650 3651 param = strsep(¶ms, ","); 3652 if (!param) { 3653 hist_err(tr, HIST_ERR_PARAM_NOT_FOUND, 0); 3654 ret = -EINVAL; 3655 goto out; 3656 } 3657 3658 param = strstrip(param); 3659 if (strlen(param) < 2) { 3660 hist_err(tr, HIST_ERR_INVALID_PARAM, errpos(param)); 3661 ret = -EINVAL; 3662 goto out; 3663 } 3664 3665 saved_param = kstrdup(param, GFP_KERNEL); 3666 if (!saved_param) { 3667 ret = -ENOMEM; 3668 goto out; 3669 } 3670 3671 if (first_param && data->use_trace_keyword) { 3672 data->synth_event_name = saved_param; 3673 first_param = false; 3674 continue; 3675 } 3676 first_param = false; 3677 3678 data->params[data->n_params++] = saved_param; 3679 } 3680 out: 3681 return ret; 3682 } 3683 3684 static int action_parse(struct trace_array *tr, char *str, struct action_data *data, 3685 enum handler_id handler) 3686 { 3687 char *action_name; 3688 int ret = 0; 3689 3690 strsep(&str, "."); 3691 if (!str) { 3692 hist_err(tr, HIST_ERR_ACTION_NOT_FOUND, 0); 3693 ret = -EINVAL; 3694 goto out; 3695 } 3696 3697 action_name = strsep(&str, "("); 3698 if (!action_name || !str) { 3699 hist_err(tr, HIST_ERR_ACTION_NOT_FOUND, 0); 3700 ret = -EINVAL; 3701 goto out; 3702 } 3703 3704 if (str_has_prefix(action_name, "save")) { 3705 char *params = strsep(&str, ")"); 3706 3707 if (!params) { 3708 hist_err(tr, HIST_ERR_NO_SAVE_PARAMS, 0); 3709 ret = -EINVAL; 3710 goto out; 3711 } 3712 3713 ret = parse_action_params(tr, params, data); 3714 if (ret) 3715 goto out; 3716 3717 if (handler == HANDLER_ONMAX) 3718 data->track_data.check_val = check_track_val_max; 3719 else if (handler == HANDLER_ONCHANGE) 3720 data->track_data.check_val = check_track_val_changed; 3721 else { 3722 hist_err(tr, HIST_ERR_ACTION_MISMATCH, errpos(action_name)); 3723 ret = -EINVAL; 3724 goto out; 3725 } 3726 3727 data->track_data.save_data = save_track_data_vars; 3728 data->fn = ontrack_action; 3729 data->action = ACTION_SAVE; 3730 } else if (str_has_prefix(action_name, "snapshot")) { 3731 char *params = strsep(&str, ")"); 3732 3733 if (!str) { 3734 hist_err(tr, HIST_ERR_NO_CLOSING_PAREN, errpos(params)); 3735 ret = -EINVAL; 3736 goto out; 3737 } 3738 3739 if (handler == HANDLER_ONMAX) 3740 data->track_data.check_val = check_track_val_max; 3741 else if (handler == HANDLER_ONCHANGE) 3742 data->track_data.check_val = check_track_val_changed; 3743 else { 3744 hist_err(tr, HIST_ERR_ACTION_MISMATCH, errpos(action_name)); 3745 ret = -EINVAL; 3746 goto out; 3747 } 3748 3749 data->track_data.save_data = save_track_data_snapshot; 3750 data->fn = ontrack_action; 3751 data->action = ACTION_SNAPSHOT; 3752 } else { 3753 char *params = strsep(&str, ")"); 3754 3755 if (str_has_prefix(action_name, "trace")) 3756 data->use_trace_keyword = true; 3757 3758 if (params) { 3759 ret = parse_action_params(tr, params, data); 3760 if (ret) 3761 goto out; 3762 } 3763 3764 if (handler == HANDLER_ONMAX) 3765 data->track_data.check_val = check_track_val_max; 3766 else if (handler == HANDLER_ONCHANGE) 3767 data->track_data.check_val = check_track_val_changed; 3768 3769 if (handler != HANDLER_ONMATCH) { 3770 data->track_data.save_data = action_trace; 3771 data->fn = ontrack_action; 3772 } else 3773 data->fn = action_trace; 3774 3775 data->action = ACTION_TRACE; 3776 } 3777 3778 data->action_name = kstrdup(action_name, GFP_KERNEL); 3779 if (!data->action_name) { 3780 ret = -ENOMEM; 3781 goto out; 3782 } 3783 3784 data->handler = handler; 3785 out: 3786 return ret; 3787 } 3788 3789 static struct action_data *track_data_parse(struct hist_trigger_data *hist_data, 3790 char *str, enum handler_id handler) 3791 { 3792 struct action_data *data; 3793 int ret = -EINVAL; 3794 char *var_str; 3795 3796 data = kzalloc(sizeof(*data), GFP_KERNEL); 3797 if (!data) 3798 return ERR_PTR(-ENOMEM); 3799 3800 var_str = strsep(&str, ")"); 3801 if (!var_str || !str) { 3802 ret = -EINVAL; 3803 goto free; 3804 } 3805 3806 data->track_data.var_str = kstrdup(var_str, GFP_KERNEL); 3807 if (!data->track_data.var_str) { 3808 ret = -ENOMEM; 3809 goto free; 3810 } 3811 3812 ret = action_parse(hist_data->event_file->tr, str, data, handler); 3813 if (ret) 3814 goto free; 3815 out: 3816 return data; 3817 free: 3818 track_data_destroy(hist_data, data); 3819 data = ERR_PTR(ret); 3820 goto out; 3821 } 3822 3823 static void onmatch_destroy(struct action_data *data) 3824 { 3825 kfree(data->match_data.event); 3826 kfree(data->match_data.event_system); 3827 3828 action_data_destroy(data); 3829 } 3830 3831 static void destroy_field_var(struct field_var *field_var) 3832 { 3833 if (!field_var) 3834 return; 3835 3836 destroy_hist_field(field_var->var, 0); 3837 destroy_hist_field(field_var->val, 0); 3838 3839 kfree(field_var); 3840 } 3841 3842 static void destroy_field_vars(struct hist_trigger_data *hist_data) 3843 { 3844 unsigned int i; 3845 3846 for (i = 0; i < hist_data->n_field_vars; i++) 3847 destroy_field_var(hist_data->field_vars[i]); 3848 3849 for (i = 0; i < hist_data->n_save_vars; i++) 3850 destroy_field_var(hist_data->save_vars[i]); 3851 } 3852 3853 static void save_field_var(struct hist_trigger_data *hist_data, 3854 struct field_var *field_var) 3855 { 3856 hist_data->field_vars[hist_data->n_field_vars++] = field_var; 3857 3858 /* Stack traces are saved in the string storage too */ 3859 if (field_var->val->flags & (HIST_FIELD_FL_STRING | HIST_FIELD_FL_STACKTRACE)) 3860 hist_data->n_field_var_str++; 3861 } 3862 3863 3864 static int check_synth_field(struct synth_event *event, 3865 struct hist_field *hist_field, 3866 unsigned int field_pos) 3867 { 3868 struct synth_field *field; 3869 3870 if (field_pos >= event->n_fields) 3871 return -EINVAL; 3872 3873 field = event->fields[field_pos]; 3874 3875 /* 3876 * A dynamic string synth field can accept static or 3877 * dynamic. A static string synth field can only accept a 3878 * same-sized static string, which is checked for later. 3879 */ 3880 if (strstr(hist_field->type, "char[") && field->is_string 3881 && field->is_dynamic) 3882 return 0; 3883 3884 if (strstr(hist_field->type, "long[") && field->is_stack) 3885 return 0; 3886 3887 if (strcmp(field->type, hist_field->type) != 0) { 3888 if (field->size != hist_field->size || 3889 (!field->is_string && field->is_signed != hist_field->is_signed)) 3890 return -EINVAL; 3891 } 3892 3893 return 0; 3894 } 3895 3896 static struct hist_field * 3897 trace_action_find_var(struct hist_trigger_data *hist_data, 3898 struct action_data *data, 3899 char *system, char *event, char *var) 3900 { 3901 struct trace_array *tr = hist_data->event_file->tr; 3902 struct hist_field *hist_field; 3903 3904 var++; /* skip '$' */ 3905 3906 hist_field = find_target_event_var(hist_data, system, event, var); 3907 if (!hist_field) { 3908 if (!system && data->handler == HANDLER_ONMATCH) { 3909 system = data->match_data.event_system; 3910 event = data->match_data.event; 3911 } 3912 3913 hist_field = find_event_var(hist_data, system, event, var); 3914 } 3915 3916 if (!hist_field) 3917 hist_err(tr, HIST_ERR_PARAM_NOT_FOUND, errpos(var)); 3918 3919 return hist_field; 3920 } 3921 3922 static struct hist_field * 3923 trace_action_create_field_var(struct hist_trigger_data *hist_data, 3924 struct action_data *data, char *system, 3925 char *event, char *var) 3926 { 3927 struct hist_field *hist_field = NULL; 3928 struct field_var *field_var; 3929 3930 /* 3931 * First try to create a field var on the target event (the 3932 * currently being defined). This will create a variable for 3933 * unqualified fields on the target event, or if qualified, 3934 * target fields that have qualified names matching the target. 3935 */ 3936 field_var = create_target_field_var(hist_data, system, event, var); 3937 3938 if (field_var && !IS_ERR(field_var)) { 3939 save_field_var(hist_data, field_var); 3940 hist_field = field_var->var; 3941 } else { 3942 field_var = NULL; 3943 /* 3944 * If no explicit system.event is specified, default to 3945 * looking for fields on the onmatch(system.event.xxx) 3946 * event. 3947 */ 3948 if (!system && data->handler == HANDLER_ONMATCH) { 3949 system = data->match_data.event_system; 3950 event = data->match_data.event; 3951 } 3952 3953 if (!event) 3954 goto free; 3955 /* 3956 * At this point, we're looking at a field on another 3957 * event. Because we can't modify a hist trigger on 3958 * another event to add a variable for a field, we need 3959 * to create a new trigger on that event and create the 3960 * variable at the same time. 3961 */ 3962 hist_field = create_field_var_hist(hist_data, system, event, var); 3963 if (IS_ERR(hist_field)) 3964 goto free; 3965 } 3966 out: 3967 return hist_field; 3968 free: 3969 destroy_field_var(field_var); 3970 hist_field = NULL; 3971 goto out; 3972 } 3973 3974 static int trace_action_create(struct hist_trigger_data *hist_data, 3975 struct action_data *data) 3976 { 3977 struct trace_array *tr = hist_data->event_file->tr; 3978 char *event_name, *param, *system = NULL; 3979 struct hist_field *hist_field, *var_ref; 3980 unsigned int i; 3981 unsigned int field_pos = 0; 3982 struct synth_event *event; 3983 char *synth_event_name; 3984 int var_ref_idx, ret = 0; 3985 3986 lockdep_assert_held(&event_mutex); 3987 3988 /* Sanity check to avoid out-of-bound write on 'data->var_ref_idx' */ 3989 if (data->n_params > SYNTH_FIELDS_MAX) 3990 return -EINVAL; 3991 3992 if (data->use_trace_keyword) 3993 synth_event_name = data->synth_event_name; 3994 else 3995 synth_event_name = data->action_name; 3996 3997 event = find_synth_event(synth_event_name); 3998 if (!event) { 3999 hist_err(tr, HIST_ERR_SYNTH_EVENT_NOT_FOUND, errpos(synth_event_name)); 4000 return -EINVAL; 4001 } 4002 4003 event->ref++; 4004 4005 for (i = 0; i < data->n_params; i++) { 4006 char *p; 4007 4008 p = param = kstrdup(data->params[i], GFP_KERNEL); 4009 if (!param) { 4010 ret = -ENOMEM; 4011 goto err; 4012 } 4013 4014 system = strsep(¶m, "."); 4015 if (!param) { 4016 param = (char *)system; 4017 system = event_name = NULL; 4018 } else { 4019 event_name = strsep(¶m, "."); 4020 if (!param) { 4021 kfree(p); 4022 ret = -EINVAL; 4023 goto err; 4024 } 4025 } 4026 4027 if (param[0] == '$') 4028 hist_field = trace_action_find_var(hist_data, data, 4029 system, event_name, 4030 param); 4031 else 4032 hist_field = trace_action_create_field_var(hist_data, 4033 data, 4034 system, 4035 event_name, 4036 param); 4037 4038 if (!hist_field) { 4039 kfree(p); 4040 ret = -EINVAL; 4041 goto err; 4042 } 4043 4044 if (check_synth_field(event, hist_field, field_pos) == 0) { 4045 var_ref = create_var_ref(hist_data, hist_field, 4046 system, event_name); 4047 if (!var_ref) { 4048 kfree(p); 4049 ret = -ENOMEM; 4050 goto err; 4051 } 4052 4053 var_ref_idx = find_var_ref_idx(hist_data, var_ref); 4054 if (WARN_ON(var_ref_idx < 0)) { 4055 kfree(p); 4056 ret = var_ref_idx; 4057 goto err; 4058 } 4059 4060 data->var_ref_idx[i] = var_ref_idx; 4061 4062 field_pos++; 4063 kfree(p); 4064 continue; 4065 } 4066 4067 hist_err(tr, HIST_ERR_SYNTH_TYPE_MISMATCH, errpos(param)); 4068 kfree(p); 4069 ret = -EINVAL; 4070 goto err; 4071 } 4072 4073 if (field_pos != event->n_fields) { 4074 hist_err(tr, HIST_ERR_SYNTH_COUNT_MISMATCH, errpos(event->name)); 4075 ret = -EINVAL; 4076 goto err; 4077 } 4078 4079 data->synth_event = event; 4080 out: 4081 return ret; 4082 err: 4083 event->ref--; 4084 4085 goto out; 4086 } 4087 4088 static int action_create(struct hist_trigger_data *hist_data, 4089 struct action_data *data) 4090 { 4091 struct trace_event_file *file = hist_data->event_file; 4092 struct trace_array *tr = file->tr; 4093 struct track_data *track_data; 4094 struct field_var *field_var; 4095 unsigned int i; 4096 char *param; 4097 int ret = 0; 4098 4099 if (data->action == ACTION_TRACE) 4100 return trace_action_create(hist_data, data); 4101 4102 if (data->action == ACTION_SNAPSHOT) { 4103 track_data = track_data_alloc(hist_data->key_size, data, hist_data); 4104 if (IS_ERR(track_data)) { 4105 ret = PTR_ERR(track_data); 4106 goto out; 4107 } 4108 4109 ret = tracing_snapshot_cond_enable(file->tr, track_data, 4110 cond_snapshot_update); 4111 if (ret) 4112 track_data_free(track_data); 4113 4114 goto out; 4115 } 4116 4117 if (data->action == ACTION_SAVE) { 4118 if (hist_data->n_save_vars) { 4119 ret = -EEXIST; 4120 hist_err(tr, HIST_ERR_TOO_MANY_SAVE_ACTIONS, 0); 4121 goto out; 4122 } 4123 4124 for (i = 0; i < data->n_params; i++) { 4125 param = kstrdup(data->params[i], GFP_KERNEL); 4126 if (!param) { 4127 ret = -ENOMEM; 4128 goto out; 4129 } 4130 4131 field_var = create_target_field_var(hist_data, NULL, NULL, param); 4132 if (IS_ERR(field_var)) { 4133 hist_err(tr, HIST_ERR_FIELD_VAR_CREATE_FAIL, 4134 errpos(param)); 4135 ret = PTR_ERR(field_var); 4136 kfree(param); 4137 goto out; 4138 } 4139 4140 hist_data->save_vars[hist_data->n_save_vars++] = field_var; 4141 if (field_var->val->flags & 4142 (HIST_FIELD_FL_STRING | HIST_FIELD_FL_STACKTRACE)) 4143 hist_data->n_save_var_str++; 4144 kfree(param); 4145 } 4146 } 4147 out: 4148 return ret; 4149 } 4150 4151 static int onmatch_create(struct hist_trigger_data *hist_data, 4152 struct action_data *data) 4153 { 4154 return action_create(hist_data, data); 4155 } 4156 4157 static struct action_data *onmatch_parse(struct trace_array *tr, char *str) 4158 { 4159 char *match_event, *match_event_system; 4160 struct action_data *data; 4161 int ret = -EINVAL; 4162 4163 data = kzalloc(sizeof(*data), GFP_KERNEL); 4164 if (!data) 4165 return ERR_PTR(-ENOMEM); 4166 4167 match_event = strsep(&str, ")"); 4168 if (!match_event || !str) { 4169 hist_err(tr, HIST_ERR_NO_CLOSING_PAREN, errpos(match_event)); 4170 goto free; 4171 } 4172 4173 match_event_system = strsep(&match_event, "."); 4174 if (!match_event) { 4175 hist_err(tr, HIST_ERR_SUBSYS_NOT_FOUND, errpos(match_event_system)); 4176 goto free; 4177 } 4178 4179 if (IS_ERR(event_file(tr, match_event_system, match_event))) { 4180 hist_err(tr, HIST_ERR_INVALID_SUBSYS_EVENT, errpos(match_event)); 4181 goto free; 4182 } 4183 4184 data->match_data.event = kstrdup(match_event, GFP_KERNEL); 4185 if (!data->match_data.event) { 4186 ret = -ENOMEM; 4187 goto free; 4188 } 4189 4190 data->match_data.event_system = kstrdup(match_event_system, GFP_KERNEL); 4191 if (!data->match_data.event_system) { 4192 ret = -ENOMEM; 4193 goto free; 4194 } 4195 4196 ret = action_parse(tr, str, data, HANDLER_ONMATCH); 4197 if (ret) 4198 goto free; 4199 out: 4200 return data; 4201 free: 4202 onmatch_destroy(data); 4203 data = ERR_PTR(ret); 4204 goto out; 4205 } 4206 4207 static int create_hitcount_val(struct hist_trigger_data *hist_data) 4208 { 4209 hist_data->fields[HITCOUNT_IDX] = 4210 create_hist_field(hist_data, NULL, HIST_FIELD_FL_HITCOUNT, NULL); 4211 if (!hist_data->fields[HITCOUNT_IDX]) 4212 return -ENOMEM; 4213 4214 hist_data->n_vals++; 4215 hist_data->n_fields++; 4216 4217 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX)) 4218 return -EINVAL; 4219 4220 return 0; 4221 } 4222 4223 static int __create_val_field(struct hist_trigger_data *hist_data, 4224 unsigned int val_idx, 4225 struct trace_event_file *file, 4226 char *var_name, char *field_str, 4227 unsigned long flags) 4228 { 4229 struct hist_field *hist_field; 4230 int ret = 0, n_subexprs = 0; 4231 4232 hist_field = parse_expr(hist_data, file, field_str, flags, var_name, &n_subexprs); 4233 if (IS_ERR(hist_field)) { 4234 ret = PTR_ERR(hist_field); 4235 goto out; 4236 } 4237 4238 /* values and variables should not have some modifiers */ 4239 if (hist_field->flags & HIST_FIELD_FL_VAR) { 4240 /* Variable */ 4241 if (hist_field->flags & (HIST_FIELD_FL_GRAPH | HIST_FIELD_FL_PERCENT | 4242 HIST_FIELD_FL_BUCKET | HIST_FIELD_FL_LOG2)) 4243 goto err; 4244 } else { 4245 /* Value */ 4246 if (hist_field->flags & (HIST_FIELD_FL_GRAPH | HIST_FIELD_FL_PERCENT | 4247 HIST_FIELD_FL_BUCKET | HIST_FIELD_FL_LOG2 | 4248 HIST_FIELD_FL_SYM | HIST_FIELD_FL_SYM_OFFSET | 4249 HIST_FIELD_FL_SYSCALL | HIST_FIELD_FL_STACKTRACE)) 4250 goto err; 4251 } 4252 4253 hist_data->fields[val_idx] = hist_field; 4254 4255 ++hist_data->n_vals; 4256 ++hist_data->n_fields; 4257 4258 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX)) 4259 ret = -EINVAL; 4260 out: 4261 return ret; 4262 err: 4263 hist_err(file->tr, HIST_ERR_BAD_FIELD_MODIFIER, errpos(field_str)); 4264 return -EINVAL; 4265 } 4266 4267 static int create_val_field(struct hist_trigger_data *hist_data, 4268 unsigned int val_idx, 4269 struct trace_event_file *file, 4270 char *field_str) 4271 { 4272 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX)) 4273 return -EINVAL; 4274 4275 return __create_val_field(hist_data, val_idx, file, NULL, field_str, 0); 4276 } 4277 4278 static const char no_comm[] = "(no comm)"; 4279 4280 static u64 hist_field_execname(struct hist_field *hist_field, 4281 struct tracing_map_elt *elt, 4282 struct trace_buffer *buffer, 4283 struct ring_buffer_event *rbe, 4284 void *event) 4285 { 4286 struct hist_elt_data *elt_data; 4287 4288 if (WARN_ON_ONCE(!elt)) 4289 return (u64)(unsigned long)no_comm; 4290 4291 elt_data = elt->private_data; 4292 4293 if (WARN_ON_ONCE(!elt_data->comm)) 4294 return (u64)(unsigned long)no_comm; 4295 4296 return (u64)(unsigned long)(elt_data->comm); 4297 } 4298 4299 static u64 hist_field_stack(struct hist_field *hist_field, 4300 struct tracing_map_elt *elt, 4301 struct trace_buffer *buffer, 4302 struct ring_buffer_event *rbe, 4303 void *event) 4304 { 4305 u32 str_item = *(u32 *)(event + hist_field->field->offset); 4306 int str_loc = str_item & 0xffff; 4307 char *addr = (char *)(event + str_loc); 4308 4309 return (u64)(unsigned long)addr; 4310 } 4311 4312 static u64 hist_fn_call(struct hist_field *hist_field, 4313 struct tracing_map_elt *elt, 4314 struct trace_buffer *buffer, 4315 struct ring_buffer_event *rbe, 4316 void *event) 4317 { 4318 switch (hist_field->fn_num) { 4319 case HIST_FIELD_FN_VAR_REF: 4320 return hist_field_var_ref(hist_field, elt, buffer, rbe, event); 4321 case HIST_FIELD_FN_COUNTER: 4322 return hist_field_counter(hist_field, elt, buffer, rbe, event); 4323 case HIST_FIELD_FN_CONST: 4324 return hist_field_const(hist_field, elt, buffer, rbe, event); 4325 case HIST_FIELD_FN_LOG2: 4326 return hist_field_log2(hist_field, elt, buffer, rbe, event); 4327 case HIST_FIELD_FN_BUCKET: 4328 return hist_field_bucket(hist_field, elt, buffer, rbe, event); 4329 case HIST_FIELD_FN_TIMESTAMP: 4330 return hist_field_timestamp(hist_field, elt, buffer, rbe, event); 4331 case HIST_FIELD_FN_CPU: 4332 return hist_field_cpu(hist_field, elt, buffer, rbe, event); 4333 case HIST_FIELD_FN_STRING: 4334 return hist_field_string(hist_field, elt, buffer, rbe, event); 4335 case HIST_FIELD_FN_DYNSTRING: 4336 return hist_field_dynstring(hist_field, elt, buffer, rbe, event); 4337 case HIST_FIELD_FN_RELDYNSTRING: 4338 return hist_field_reldynstring(hist_field, elt, buffer, rbe, event); 4339 case HIST_FIELD_FN_PSTRING: 4340 return hist_field_pstring(hist_field, elt, buffer, rbe, event); 4341 case HIST_FIELD_FN_S64: 4342 return hist_field_s64(hist_field, elt, buffer, rbe, event); 4343 case HIST_FIELD_FN_U64: 4344 return hist_field_u64(hist_field, elt, buffer, rbe, event); 4345 case HIST_FIELD_FN_S32: 4346 return hist_field_s32(hist_field, elt, buffer, rbe, event); 4347 case HIST_FIELD_FN_U32: 4348 return hist_field_u32(hist_field, elt, buffer, rbe, event); 4349 case HIST_FIELD_FN_S16: 4350 return hist_field_s16(hist_field, elt, buffer, rbe, event); 4351 case HIST_FIELD_FN_U16: 4352 return hist_field_u16(hist_field, elt, buffer, rbe, event); 4353 case HIST_FIELD_FN_S8: 4354 return hist_field_s8(hist_field, elt, buffer, rbe, event); 4355 case HIST_FIELD_FN_U8: 4356 return hist_field_u8(hist_field, elt, buffer, rbe, event); 4357 case HIST_FIELD_FN_UMINUS: 4358 return hist_field_unary_minus(hist_field, elt, buffer, rbe, event); 4359 case HIST_FIELD_FN_MINUS: 4360 return hist_field_minus(hist_field, elt, buffer, rbe, event); 4361 case HIST_FIELD_FN_PLUS: 4362 return hist_field_plus(hist_field, elt, buffer, rbe, event); 4363 case HIST_FIELD_FN_DIV: 4364 return hist_field_div(hist_field, elt, buffer, rbe, event); 4365 case HIST_FIELD_FN_MULT: 4366 return hist_field_mult(hist_field, elt, buffer, rbe, event); 4367 case HIST_FIELD_FN_DIV_POWER2: 4368 return div_by_power_of_two(hist_field, elt, buffer, rbe, event); 4369 case HIST_FIELD_FN_DIV_NOT_POWER2: 4370 return div_by_not_power_of_two(hist_field, elt, buffer, rbe, event); 4371 case HIST_FIELD_FN_DIV_MULT_SHIFT: 4372 return div_by_mult_and_shift(hist_field, elt, buffer, rbe, event); 4373 case HIST_FIELD_FN_EXECNAME: 4374 return hist_field_execname(hist_field, elt, buffer, rbe, event); 4375 case HIST_FIELD_FN_STACK: 4376 return hist_field_stack(hist_field, elt, buffer, rbe, event); 4377 default: 4378 return 0; 4379 } 4380 } 4381 4382 /* Convert a var that points to common_pid.execname to a string */ 4383 static void update_var_execname(struct hist_field *hist_field) 4384 { 4385 hist_field->flags = HIST_FIELD_FL_STRING | HIST_FIELD_FL_VAR | 4386 HIST_FIELD_FL_EXECNAME; 4387 hist_field->size = MAX_FILTER_STR_VAL; 4388 hist_field->is_signed = 0; 4389 4390 kfree_const(hist_field->type); 4391 hist_field->type = "char[]"; 4392 4393 hist_field->fn_num = HIST_FIELD_FN_EXECNAME; 4394 } 4395 4396 static int create_var_field(struct hist_trigger_data *hist_data, 4397 unsigned int val_idx, 4398 struct trace_event_file *file, 4399 char *var_name, char *expr_str) 4400 { 4401 struct trace_array *tr = hist_data->event_file->tr; 4402 unsigned long flags = 0; 4403 int ret; 4404 4405 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX)) 4406 return -EINVAL; 4407 4408 if (find_var(hist_data, file, var_name) && !hist_data->remove) { 4409 hist_err(tr, HIST_ERR_DUPLICATE_VAR, errpos(var_name)); 4410 return -EINVAL; 4411 } 4412 4413 flags |= HIST_FIELD_FL_VAR; 4414 hist_data->n_vars++; 4415 if (WARN_ON(hist_data->n_vars > TRACING_MAP_VARS_MAX)) 4416 return -EINVAL; 4417 4418 ret = __create_val_field(hist_data, val_idx, file, var_name, expr_str, flags); 4419 4420 if (!ret && hist_data->fields[val_idx]->flags & HIST_FIELD_FL_EXECNAME) 4421 update_var_execname(hist_data->fields[val_idx]); 4422 4423 if (!ret && hist_data->fields[val_idx]->flags & 4424 (HIST_FIELD_FL_STRING | HIST_FIELD_FL_STACKTRACE)) 4425 hist_data->fields[val_idx]->var_str_idx = hist_data->n_var_str++; 4426 4427 return ret; 4428 } 4429 4430 static int create_val_fields(struct hist_trigger_data *hist_data, 4431 struct trace_event_file *file) 4432 { 4433 unsigned int i, j = 1, n_hitcount = 0; 4434 char *fields_str, *field_str; 4435 int ret; 4436 4437 ret = create_hitcount_val(hist_data); 4438 if (ret) 4439 goto out; 4440 4441 fields_str = hist_data->attrs->vals_str; 4442 if (!fields_str) 4443 goto out; 4444 4445 for (i = 0, j = 1; i < TRACING_MAP_VALS_MAX && 4446 j < TRACING_MAP_VALS_MAX; i++) { 4447 field_str = strsep(&fields_str, ","); 4448 if (!field_str) 4449 break; 4450 4451 if (strcmp(field_str, "hitcount") == 0) { 4452 if (!n_hitcount++) 4453 continue; 4454 } 4455 4456 ret = create_val_field(hist_data, j++, file, field_str); 4457 if (ret) 4458 goto out; 4459 } 4460 4461 if (fields_str && (strcmp(fields_str, "hitcount") != 0)) 4462 ret = -EINVAL; 4463 out: 4464 /* There is only raw hitcount but nohitcount suppresses it. */ 4465 if (j == 1 && hist_data->attrs->no_hitcount) { 4466 hist_err(hist_data->event_file->tr, HIST_ERR_NEED_NOHC_VAL, 0); 4467 ret = -ENOENT; 4468 } 4469 4470 return ret; 4471 } 4472 4473 static int create_key_field(struct hist_trigger_data *hist_data, 4474 unsigned int key_idx, 4475 unsigned int key_offset, 4476 struct trace_event_file *file, 4477 char *field_str) 4478 { 4479 struct trace_array *tr = hist_data->event_file->tr; 4480 struct hist_field *hist_field = NULL; 4481 unsigned long flags = 0; 4482 unsigned int key_size; 4483 int ret = 0, n_subexprs = 0; 4484 4485 if (WARN_ON(key_idx >= HIST_FIELDS_MAX)) 4486 return -EINVAL; 4487 4488 flags |= HIST_FIELD_FL_KEY; 4489 4490 if (strcmp(field_str, "stacktrace") == 0) { 4491 flags |= HIST_FIELD_FL_STACKTRACE; 4492 key_size = sizeof(unsigned long) * HIST_STACKTRACE_DEPTH; 4493 hist_field = create_hist_field(hist_data, NULL, flags, NULL); 4494 } else { 4495 hist_field = parse_expr(hist_data, file, field_str, flags, 4496 NULL, &n_subexprs); 4497 if (IS_ERR(hist_field)) { 4498 ret = PTR_ERR(hist_field); 4499 goto out; 4500 } 4501 4502 if (field_has_hist_vars(hist_field, 0)) { 4503 hist_err(tr, HIST_ERR_INVALID_REF_KEY, errpos(field_str)); 4504 destroy_hist_field(hist_field, 0); 4505 ret = -EINVAL; 4506 goto out; 4507 } 4508 4509 key_size = hist_field->size; 4510 } 4511 4512 hist_data->fields[key_idx] = hist_field; 4513 4514 key_size = ALIGN(key_size, sizeof(u64)); 4515 hist_data->fields[key_idx]->size = key_size; 4516 hist_data->fields[key_idx]->offset = key_offset; 4517 4518 hist_data->key_size += key_size; 4519 4520 if (hist_data->key_size > HIST_KEY_SIZE_MAX) { 4521 ret = -EINVAL; 4522 goto out; 4523 } 4524 4525 hist_data->n_keys++; 4526 hist_data->n_fields++; 4527 4528 if (WARN_ON(hist_data->n_keys > TRACING_MAP_KEYS_MAX)) 4529 return -EINVAL; 4530 4531 ret = key_size; 4532 out: 4533 return ret; 4534 } 4535 4536 static int create_key_fields(struct hist_trigger_data *hist_data, 4537 struct trace_event_file *file) 4538 { 4539 unsigned int i, key_offset = 0, n_vals = hist_data->n_vals; 4540 char *fields_str, *field_str; 4541 int ret = -EINVAL; 4542 4543 fields_str = hist_data->attrs->keys_str; 4544 if (!fields_str) 4545 goto out; 4546 4547 for (i = n_vals; i < n_vals + TRACING_MAP_KEYS_MAX; i++) { 4548 field_str = strsep(&fields_str, ","); 4549 if (!field_str) 4550 break; 4551 ret = create_key_field(hist_data, i, key_offset, 4552 file, field_str); 4553 if (ret < 0) 4554 goto out; 4555 key_offset += ret; 4556 } 4557 if (fields_str) { 4558 ret = -EINVAL; 4559 goto out; 4560 } 4561 ret = 0; 4562 out: 4563 return ret; 4564 } 4565 4566 static int create_var_fields(struct hist_trigger_data *hist_data, 4567 struct trace_event_file *file) 4568 { 4569 unsigned int i, j = hist_data->n_vals; 4570 int ret = 0; 4571 4572 unsigned int n_vars = hist_data->attrs->var_defs.n_vars; 4573 4574 for (i = 0; i < n_vars; i++) { 4575 char *var_name = hist_data->attrs->var_defs.name[i]; 4576 char *expr = hist_data->attrs->var_defs.expr[i]; 4577 4578 ret = create_var_field(hist_data, j++, file, var_name, expr); 4579 if (ret) 4580 goto out; 4581 } 4582 out: 4583 return ret; 4584 } 4585 4586 static void free_var_defs(struct hist_trigger_data *hist_data) 4587 { 4588 unsigned int i; 4589 4590 for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) { 4591 kfree(hist_data->attrs->var_defs.name[i]); 4592 kfree(hist_data->attrs->var_defs.expr[i]); 4593 } 4594 4595 hist_data->attrs->var_defs.n_vars = 0; 4596 } 4597 4598 static int parse_var_defs(struct hist_trigger_data *hist_data) 4599 { 4600 struct trace_array *tr = hist_data->event_file->tr; 4601 char *s, *str, *var_name, *field_str; 4602 unsigned int i, j, n_vars = 0; 4603 int ret = 0; 4604 4605 for (i = 0; i < hist_data->attrs->n_assignments; i++) { 4606 str = hist_data->attrs->assignment_str[i]; 4607 for (j = 0; j < TRACING_MAP_VARS_MAX; j++) { 4608 field_str = strsep(&str, ","); 4609 if (!field_str) 4610 break; 4611 4612 var_name = strsep(&field_str, "="); 4613 if (!var_name || !field_str) { 4614 hist_err(tr, HIST_ERR_MALFORMED_ASSIGNMENT, 4615 errpos(var_name)); 4616 ret = -EINVAL; 4617 goto free; 4618 } 4619 4620 if (n_vars == TRACING_MAP_VARS_MAX) { 4621 hist_err(tr, HIST_ERR_TOO_MANY_VARS, errpos(var_name)); 4622 ret = -EINVAL; 4623 goto free; 4624 } 4625 4626 s = kstrdup(var_name, GFP_KERNEL); 4627 if (!s) { 4628 ret = -ENOMEM; 4629 goto free; 4630 } 4631 hist_data->attrs->var_defs.name[n_vars] = s; 4632 4633 s = kstrdup(field_str, GFP_KERNEL); 4634 if (!s) { 4635 kfree(hist_data->attrs->var_defs.name[n_vars]); 4636 hist_data->attrs->var_defs.name[n_vars] = NULL; 4637 ret = -ENOMEM; 4638 goto free; 4639 } 4640 hist_data->attrs->var_defs.expr[n_vars++] = s; 4641 4642 hist_data->attrs->var_defs.n_vars = n_vars; 4643 } 4644 } 4645 4646 return ret; 4647 free: 4648 free_var_defs(hist_data); 4649 4650 return ret; 4651 } 4652 4653 static int create_hist_fields(struct hist_trigger_data *hist_data, 4654 struct trace_event_file *file) 4655 { 4656 int ret; 4657 4658 ret = parse_var_defs(hist_data); 4659 if (ret) 4660 return ret; 4661 4662 ret = create_val_fields(hist_data, file); 4663 if (ret) 4664 goto out; 4665 4666 ret = create_var_fields(hist_data, file); 4667 if (ret) 4668 goto out; 4669 4670 ret = create_key_fields(hist_data, file); 4671 4672 out: 4673 free_var_defs(hist_data); 4674 4675 return ret; 4676 } 4677 4678 static int is_descending(struct trace_array *tr, const char *str) 4679 { 4680 if (!str) 4681 return 0; 4682 4683 if (strcmp(str, "descending") == 0) 4684 return 1; 4685 4686 if (strcmp(str, "ascending") == 0) 4687 return 0; 4688 4689 hist_err(tr, HIST_ERR_INVALID_SORT_MODIFIER, errpos((char *)str)); 4690 4691 return -EINVAL; 4692 } 4693 4694 static int create_sort_keys(struct hist_trigger_data *hist_data) 4695 { 4696 struct trace_array *tr = hist_data->event_file->tr; 4697 char *fields_str = hist_data->attrs->sort_key_str; 4698 struct tracing_map_sort_key *sort_key; 4699 int descending, ret = 0; 4700 unsigned int i, j, k; 4701 4702 hist_data->n_sort_keys = 1; /* we always have at least one, hitcount */ 4703 4704 if (!fields_str) 4705 goto out; 4706 4707 for (i = 0; i < TRACING_MAP_SORT_KEYS_MAX; i++) { 4708 struct hist_field *hist_field; 4709 char *field_str, *field_name; 4710 const char *test_name; 4711 4712 sort_key = &hist_data->sort_keys[i]; 4713 4714 field_str = strsep(&fields_str, ","); 4715 if (!field_str) 4716 break; 4717 4718 if (!*field_str) { 4719 ret = -EINVAL; 4720 hist_err(tr, HIST_ERR_EMPTY_SORT_FIELD, errpos("sort=")); 4721 break; 4722 } 4723 4724 if ((i == TRACING_MAP_SORT_KEYS_MAX - 1) && fields_str) { 4725 hist_err(tr, HIST_ERR_TOO_MANY_SORT_FIELDS, errpos("sort=")); 4726 ret = -EINVAL; 4727 break; 4728 } 4729 4730 field_name = strsep(&field_str, "."); 4731 if (!field_name || !*field_name) { 4732 ret = -EINVAL; 4733 hist_err(tr, HIST_ERR_EMPTY_SORT_FIELD, errpos("sort=")); 4734 break; 4735 } 4736 4737 if (strcmp(field_name, "hitcount") == 0) { 4738 descending = is_descending(tr, field_str); 4739 if (descending < 0) { 4740 ret = descending; 4741 break; 4742 } 4743 sort_key->descending = descending; 4744 continue; 4745 } 4746 4747 for (j = 1, k = 1; j < hist_data->n_fields; j++) { 4748 unsigned int idx; 4749 4750 hist_field = hist_data->fields[j]; 4751 if (hist_field->flags & HIST_FIELD_FL_VAR) 4752 continue; 4753 4754 idx = k++; 4755 4756 test_name = hist_field_name(hist_field, 0); 4757 4758 if (strcmp(field_name, test_name) == 0) { 4759 sort_key->field_idx = idx; 4760 descending = is_descending(tr, field_str); 4761 if (descending < 0) { 4762 ret = descending; 4763 goto out; 4764 } 4765 sort_key->descending = descending; 4766 break; 4767 } 4768 } 4769 if (j == hist_data->n_fields) { 4770 ret = -EINVAL; 4771 hist_err(tr, HIST_ERR_INVALID_SORT_FIELD, errpos(field_name)); 4772 break; 4773 } 4774 } 4775 4776 hist_data->n_sort_keys = i; 4777 out: 4778 return ret; 4779 } 4780 4781 static void destroy_actions(struct hist_trigger_data *hist_data) 4782 { 4783 unsigned int i; 4784 4785 for (i = 0; i < hist_data->n_actions; i++) { 4786 struct action_data *data = hist_data->actions[i]; 4787 4788 if (data->handler == HANDLER_ONMATCH) 4789 onmatch_destroy(data); 4790 else if (data->handler == HANDLER_ONMAX || 4791 data->handler == HANDLER_ONCHANGE) 4792 track_data_destroy(hist_data, data); 4793 else 4794 kfree(data); 4795 } 4796 } 4797 4798 static int parse_actions(struct hist_trigger_data *hist_data) 4799 { 4800 struct trace_array *tr = hist_data->event_file->tr; 4801 struct action_data *data; 4802 unsigned int i; 4803 int ret = 0; 4804 char *str; 4805 int len; 4806 4807 for (i = 0; i < hist_data->attrs->n_actions; i++) { 4808 enum handler_id hid = 0; 4809 char *action_str; 4810 4811 str = hist_data->attrs->action_str[i]; 4812 4813 if ((len = str_has_prefix(str, "onmatch("))) 4814 hid = HANDLER_ONMATCH; 4815 else if ((len = str_has_prefix(str, "onmax("))) 4816 hid = HANDLER_ONMAX; 4817 else if ((len = str_has_prefix(str, "onchange("))) 4818 hid = HANDLER_ONCHANGE; 4819 4820 action_str = str + len; 4821 4822 switch (hid) { 4823 case HANDLER_ONMATCH: 4824 data = onmatch_parse(tr, action_str); 4825 break; 4826 case HANDLER_ONMAX: 4827 case HANDLER_ONCHANGE: 4828 data = track_data_parse(hist_data, action_str, hid); 4829 break; 4830 default: 4831 data = ERR_PTR(-EINVAL); 4832 break; 4833 } 4834 4835 if (IS_ERR(data)) { 4836 ret = PTR_ERR(data); 4837 break; 4838 } 4839 4840 hist_data->actions[hist_data->n_actions++] = data; 4841 } 4842 4843 return ret; 4844 } 4845 4846 static int create_actions(struct hist_trigger_data *hist_data) 4847 { 4848 struct action_data *data; 4849 unsigned int i; 4850 int ret = 0; 4851 4852 for (i = 0; i < hist_data->attrs->n_actions; i++) { 4853 data = hist_data->actions[i]; 4854 4855 if (data->handler == HANDLER_ONMATCH) { 4856 ret = onmatch_create(hist_data, data); 4857 if (ret) 4858 break; 4859 } else if (data->handler == HANDLER_ONMAX || 4860 data->handler == HANDLER_ONCHANGE) { 4861 ret = track_data_create(hist_data, data); 4862 if (ret) 4863 break; 4864 } else { 4865 ret = -EINVAL; 4866 break; 4867 } 4868 } 4869 4870 return ret; 4871 } 4872 4873 static void print_actions(struct seq_file *m, 4874 struct hist_trigger_data *hist_data, 4875 struct tracing_map_elt *elt) 4876 { 4877 unsigned int i; 4878 4879 for (i = 0; i < hist_data->n_actions; i++) { 4880 struct action_data *data = hist_data->actions[i]; 4881 4882 if (data->action == ACTION_SNAPSHOT) 4883 continue; 4884 4885 if (data->handler == HANDLER_ONMAX || 4886 data->handler == HANDLER_ONCHANGE) 4887 track_data_print(m, hist_data, elt, data); 4888 } 4889 } 4890 4891 static void print_action_spec(struct seq_file *m, 4892 struct hist_trigger_data *hist_data, 4893 struct action_data *data) 4894 { 4895 unsigned int i; 4896 4897 if (data->action == ACTION_SAVE) { 4898 for (i = 0; i < hist_data->n_save_vars; i++) { 4899 seq_printf(m, "%s", hist_data->save_vars[i]->var->var.name); 4900 if (i < hist_data->n_save_vars - 1) 4901 seq_puts(m, ","); 4902 } 4903 } else if (data->action == ACTION_TRACE) { 4904 if (data->use_trace_keyword) 4905 seq_printf(m, "%s", data->synth_event_name); 4906 for (i = 0; i < data->n_params; i++) { 4907 if (i || data->use_trace_keyword) 4908 seq_puts(m, ","); 4909 seq_printf(m, "%s", data->params[i]); 4910 } 4911 } 4912 } 4913 4914 static void print_track_data_spec(struct seq_file *m, 4915 struct hist_trigger_data *hist_data, 4916 struct action_data *data) 4917 { 4918 if (data->handler == HANDLER_ONMAX) 4919 seq_puts(m, ":onmax("); 4920 else if (data->handler == HANDLER_ONCHANGE) 4921 seq_puts(m, ":onchange("); 4922 seq_printf(m, "%s", data->track_data.var_str); 4923 seq_printf(m, ").%s(", data->action_name); 4924 4925 print_action_spec(m, hist_data, data); 4926 4927 seq_puts(m, ")"); 4928 } 4929 4930 static void print_onmatch_spec(struct seq_file *m, 4931 struct hist_trigger_data *hist_data, 4932 struct action_data *data) 4933 { 4934 seq_printf(m, ":onmatch(%s.%s).", data->match_data.event_system, 4935 data->match_data.event); 4936 4937 seq_printf(m, "%s(", data->action_name); 4938 4939 print_action_spec(m, hist_data, data); 4940 4941 seq_puts(m, ")"); 4942 } 4943 4944 static bool actions_match(struct hist_trigger_data *hist_data, 4945 struct hist_trigger_data *hist_data_test) 4946 { 4947 unsigned int i, j; 4948 4949 if (hist_data->n_actions != hist_data_test->n_actions) 4950 return false; 4951 4952 for (i = 0; i < hist_data->n_actions; i++) { 4953 struct action_data *data = hist_data->actions[i]; 4954 struct action_data *data_test = hist_data_test->actions[i]; 4955 char *action_name, *action_name_test; 4956 4957 if (data->handler != data_test->handler) 4958 return false; 4959 if (data->action != data_test->action) 4960 return false; 4961 4962 if (data->n_params != data_test->n_params) 4963 return false; 4964 4965 for (j = 0; j < data->n_params; j++) { 4966 if (strcmp(data->params[j], data_test->params[j]) != 0) 4967 return false; 4968 } 4969 4970 if (data->use_trace_keyword) 4971 action_name = data->synth_event_name; 4972 else 4973 action_name = data->action_name; 4974 4975 if (data_test->use_trace_keyword) 4976 action_name_test = data_test->synth_event_name; 4977 else 4978 action_name_test = data_test->action_name; 4979 4980 if (strcmp(action_name, action_name_test) != 0) 4981 return false; 4982 4983 if (data->handler == HANDLER_ONMATCH) { 4984 if (strcmp(data->match_data.event_system, 4985 data_test->match_data.event_system) != 0) 4986 return false; 4987 if (strcmp(data->match_data.event, 4988 data_test->match_data.event) != 0) 4989 return false; 4990 } else if (data->handler == HANDLER_ONMAX || 4991 data->handler == HANDLER_ONCHANGE) { 4992 if (strcmp(data->track_data.var_str, 4993 data_test->track_data.var_str) != 0) 4994 return false; 4995 } 4996 } 4997 4998 return true; 4999 } 5000 5001 5002 static void print_actions_spec(struct seq_file *m, 5003 struct hist_trigger_data *hist_data) 5004 { 5005 unsigned int i; 5006 5007 for (i = 0; i < hist_data->n_actions; i++) { 5008 struct action_data *data = hist_data->actions[i]; 5009 5010 if (data->handler == HANDLER_ONMATCH) 5011 print_onmatch_spec(m, hist_data, data); 5012 else if (data->handler == HANDLER_ONMAX || 5013 data->handler == HANDLER_ONCHANGE) 5014 print_track_data_spec(m, hist_data, data); 5015 } 5016 } 5017 5018 static void destroy_field_var_hists(struct hist_trigger_data *hist_data) 5019 { 5020 unsigned int i; 5021 5022 for (i = 0; i < hist_data->n_field_var_hists; i++) { 5023 kfree(hist_data->field_var_hists[i]->cmd); 5024 kfree(hist_data->field_var_hists[i]); 5025 } 5026 } 5027 5028 static void destroy_hist_data(struct hist_trigger_data *hist_data) 5029 { 5030 if (!hist_data) 5031 return; 5032 5033 destroy_hist_trigger_attrs(hist_data->attrs); 5034 destroy_hist_fields(hist_data); 5035 tracing_map_destroy(hist_data->map); 5036 5037 destroy_actions(hist_data); 5038 destroy_field_vars(hist_data); 5039 destroy_field_var_hists(hist_data); 5040 5041 kfree(hist_data); 5042 } 5043 5044 static int create_tracing_map_fields(struct hist_trigger_data *hist_data) 5045 { 5046 struct tracing_map *map = hist_data->map; 5047 struct ftrace_event_field *field; 5048 struct hist_field *hist_field; 5049 int i, idx = 0; 5050 5051 for_each_hist_field(i, hist_data) { 5052 hist_field = hist_data->fields[i]; 5053 if (hist_field->flags & HIST_FIELD_FL_KEY) { 5054 tracing_map_cmp_fn_t cmp_fn; 5055 5056 field = hist_field->field; 5057 5058 if (hist_field->flags & HIST_FIELD_FL_STACKTRACE) 5059 cmp_fn = tracing_map_cmp_none; 5060 else if (!field || hist_field->flags & HIST_FIELD_FL_CPU) 5061 cmp_fn = tracing_map_cmp_num(hist_field->size, 5062 hist_field->is_signed); 5063 else if (is_string_field(field)) 5064 cmp_fn = tracing_map_cmp_string; 5065 else 5066 cmp_fn = tracing_map_cmp_num(field->size, 5067 field->is_signed); 5068 idx = tracing_map_add_key_field(map, 5069 hist_field->offset, 5070 cmp_fn); 5071 } else if (!(hist_field->flags & HIST_FIELD_FL_VAR)) 5072 idx = tracing_map_add_sum_field(map); 5073 5074 if (idx < 0) 5075 return idx; 5076 5077 if (hist_field->flags & HIST_FIELD_FL_VAR) { 5078 idx = tracing_map_add_var(map); 5079 if (idx < 0) 5080 return idx; 5081 hist_field->var.idx = idx; 5082 hist_field->var.hist_data = hist_data; 5083 } 5084 } 5085 5086 return 0; 5087 } 5088 5089 static struct hist_trigger_data * 5090 create_hist_data(unsigned int map_bits, 5091 struct hist_trigger_attrs *attrs, 5092 struct trace_event_file *file, 5093 bool remove) 5094 { 5095 const struct tracing_map_ops *map_ops = NULL; 5096 struct hist_trigger_data *hist_data; 5097 int ret = 0; 5098 5099 hist_data = kzalloc(sizeof(*hist_data), GFP_KERNEL); 5100 if (!hist_data) 5101 return ERR_PTR(-ENOMEM); 5102 5103 hist_data->attrs = attrs; 5104 hist_data->remove = remove; 5105 hist_data->event_file = file; 5106 5107 ret = parse_actions(hist_data); 5108 if (ret) 5109 goto free; 5110 5111 ret = create_hist_fields(hist_data, file); 5112 if (ret) 5113 goto free; 5114 5115 ret = create_sort_keys(hist_data); 5116 if (ret) 5117 goto free; 5118 5119 map_ops = &hist_trigger_elt_data_ops; 5120 5121 hist_data->map = tracing_map_create(map_bits, hist_data->key_size, 5122 map_ops, hist_data); 5123 if (IS_ERR(hist_data->map)) { 5124 ret = PTR_ERR(hist_data->map); 5125 hist_data->map = NULL; 5126 goto free; 5127 } 5128 5129 ret = create_tracing_map_fields(hist_data); 5130 if (ret) 5131 goto free; 5132 out: 5133 return hist_data; 5134 free: 5135 hist_data->attrs = NULL; 5136 5137 destroy_hist_data(hist_data); 5138 5139 hist_data = ERR_PTR(ret); 5140 5141 goto out; 5142 } 5143 5144 static void hist_trigger_elt_update(struct hist_trigger_data *hist_data, 5145 struct tracing_map_elt *elt, 5146 struct trace_buffer *buffer, void *rec, 5147 struct ring_buffer_event *rbe, 5148 u64 *var_ref_vals) 5149 { 5150 struct hist_elt_data *elt_data; 5151 struct hist_field *hist_field; 5152 unsigned int i, var_idx; 5153 u64 hist_val; 5154 5155 elt_data = elt->private_data; 5156 elt_data->var_ref_vals = var_ref_vals; 5157 5158 for_each_hist_val_field(i, hist_data) { 5159 hist_field = hist_data->fields[i]; 5160 hist_val = hist_fn_call(hist_field, elt, buffer, rbe, rec); 5161 if (hist_field->flags & HIST_FIELD_FL_VAR) { 5162 var_idx = hist_field->var.idx; 5163 5164 if (hist_field->flags & 5165 (HIST_FIELD_FL_STRING | HIST_FIELD_FL_STACKTRACE)) { 5166 unsigned int str_start, var_str_idx, idx; 5167 char *str, *val_str; 5168 unsigned int size; 5169 5170 str_start = hist_data->n_field_var_str + 5171 hist_data->n_save_var_str; 5172 var_str_idx = hist_field->var_str_idx; 5173 idx = str_start + var_str_idx; 5174 5175 str = elt_data->field_var_str[idx]; 5176 val_str = (char *)(uintptr_t)hist_val; 5177 5178 if (hist_field->flags & HIST_FIELD_FL_STRING) { 5179 size = min(hist_field->size, STR_VAR_LEN_MAX); 5180 strscpy(str, val_str, size); 5181 } else { 5182 char *stack_start = str + sizeof(unsigned long); 5183 int e; 5184 5185 e = stack_trace_save((void *)stack_start, 5186 HIST_STACKTRACE_DEPTH, 5187 HIST_STACKTRACE_SKIP); 5188 if (e < HIST_STACKTRACE_DEPTH - 1) 5189 ((unsigned long *)stack_start)[e] = 0; 5190 *((unsigned long *)str) = e; 5191 } 5192 hist_val = (u64)(uintptr_t)str; 5193 } 5194 tracing_map_set_var(elt, var_idx, hist_val); 5195 continue; 5196 } 5197 tracing_map_update_sum(elt, i, hist_val); 5198 } 5199 5200 for_each_hist_key_field(i, hist_data) { 5201 hist_field = hist_data->fields[i]; 5202 if (hist_field->flags & HIST_FIELD_FL_VAR) { 5203 hist_val = hist_fn_call(hist_field, elt, buffer, rbe, rec); 5204 var_idx = hist_field->var.idx; 5205 tracing_map_set_var(elt, var_idx, hist_val); 5206 } 5207 } 5208 5209 update_field_vars(hist_data, elt, buffer, rbe, rec); 5210 } 5211 5212 static inline void add_to_key(char *compound_key, void *key, 5213 struct hist_field *key_field, void *rec) 5214 { 5215 size_t size = key_field->size; 5216 5217 if (key_field->flags & HIST_FIELD_FL_STRING) { 5218 struct ftrace_event_field *field; 5219 5220 field = key_field->field; 5221 if (field->filter_type == FILTER_DYN_STRING || 5222 field->filter_type == FILTER_RDYN_STRING) 5223 size = *(u32 *)(rec + field->offset) >> 16; 5224 else if (field->filter_type == FILTER_STATIC_STRING) 5225 size = field->size; 5226 5227 /* ensure NULL-termination */ 5228 if (size > key_field->size - 1) 5229 size = key_field->size - 1; 5230 5231 strncpy(compound_key + key_field->offset, (char *)key, size); 5232 } else 5233 memcpy(compound_key + key_field->offset, key, size); 5234 } 5235 5236 static void 5237 hist_trigger_actions(struct hist_trigger_data *hist_data, 5238 struct tracing_map_elt *elt, 5239 struct trace_buffer *buffer, void *rec, 5240 struct ring_buffer_event *rbe, void *key, 5241 u64 *var_ref_vals) 5242 { 5243 struct action_data *data; 5244 unsigned int i; 5245 5246 for (i = 0; i < hist_data->n_actions; i++) { 5247 data = hist_data->actions[i]; 5248 data->fn(hist_data, elt, buffer, rec, rbe, key, data, var_ref_vals); 5249 } 5250 } 5251 5252 static void event_hist_trigger(struct event_trigger_data *data, 5253 struct trace_buffer *buffer, void *rec, 5254 struct ring_buffer_event *rbe) 5255 { 5256 struct hist_trigger_data *hist_data = data->private_data; 5257 bool use_compound_key = (hist_data->n_keys > 1); 5258 unsigned long entries[HIST_STACKTRACE_DEPTH]; 5259 u64 var_ref_vals[TRACING_MAP_VARS_MAX]; 5260 char compound_key[HIST_KEY_SIZE_MAX]; 5261 struct tracing_map_elt *elt = NULL; 5262 struct hist_field *key_field; 5263 u64 field_contents; 5264 void *key = NULL; 5265 unsigned int i; 5266 5267 if (unlikely(!rbe)) 5268 return; 5269 5270 memset(compound_key, 0, hist_data->key_size); 5271 5272 for_each_hist_key_field(i, hist_data) { 5273 key_field = hist_data->fields[i]; 5274 5275 if (key_field->flags & HIST_FIELD_FL_STACKTRACE) { 5276 memset(entries, 0, HIST_STACKTRACE_SIZE); 5277 if (key_field->field) { 5278 unsigned long *stack, n_entries; 5279 5280 field_contents = hist_fn_call(key_field, elt, buffer, rbe, rec); 5281 stack = (unsigned long *)(long)field_contents; 5282 n_entries = *stack; 5283 memcpy(entries, ++stack, n_entries * sizeof(unsigned long)); 5284 } else { 5285 stack_trace_save(entries, HIST_STACKTRACE_DEPTH, 5286 HIST_STACKTRACE_SKIP); 5287 } 5288 key = entries; 5289 } else { 5290 field_contents = hist_fn_call(key_field, elt, buffer, rbe, rec); 5291 if (key_field->flags & HIST_FIELD_FL_STRING) { 5292 key = (void *)(unsigned long)field_contents; 5293 use_compound_key = true; 5294 } else 5295 key = (void *)&field_contents; 5296 } 5297 5298 if (use_compound_key) 5299 add_to_key(compound_key, key, key_field, rec); 5300 } 5301 5302 if (use_compound_key) 5303 key = compound_key; 5304 5305 if (hist_data->n_var_refs && 5306 !resolve_var_refs(hist_data, key, var_ref_vals, false)) 5307 return; 5308 5309 elt = tracing_map_insert(hist_data->map, key); 5310 if (!elt) 5311 return; 5312 5313 hist_trigger_elt_update(hist_data, elt, buffer, rec, rbe, var_ref_vals); 5314 5315 if (resolve_var_refs(hist_data, key, var_ref_vals, true)) 5316 hist_trigger_actions(hist_data, elt, buffer, rec, rbe, key, var_ref_vals); 5317 } 5318 5319 static void hist_trigger_stacktrace_print(struct seq_file *m, 5320 unsigned long *stacktrace_entries, 5321 unsigned int max_entries) 5322 { 5323 unsigned int spaces = 8; 5324 unsigned int i; 5325 5326 for (i = 0; i < max_entries; i++) { 5327 if (!stacktrace_entries[i]) 5328 return; 5329 5330 seq_printf(m, "%*c", 1 + spaces, ' '); 5331 seq_printf(m, "%pS\n", (void*)stacktrace_entries[i]); 5332 } 5333 } 5334 5335 static void hist_trigger_print_key(struct seq_file *m, 5336 struct hist_trigger_data *hist_data, 5337 void *key, 5338 struct tracing_map_elt *elt) 5339 { 5340 struct hist_field *key_field; 5341 bool multiline = false; 5342 const char *field_name; 5343 unsigned int i; 5344 u64 uval; 5345 5346 seq_puts(m, "{ "); 5347 5348 for_each_hist_key_field(i, hist_data) { 5349 key_field = hist_data->fields[i]; 5350 5351 if (i > hist_data->n_vals) 5352 seq_puts(m, ", "); 5353 5354 field_name = hist_field_name(key_field, 0); 5355 5356 if (key_field->flags & HIST_FIELD_FL_HEX) { 5357 uval = *(u64 *)(key + key_field->offset); 5358 seq_printf(m, "%s: %llx", field_name, uval); 5359 } else if (key_field->flags & HIST_FIELD_FL_SYM) { 5360 uval = *(u64 *)(key + key_field->offset); 5361 seq_printf(m, "%s: [%llx] %-45ps", field_name, 5362 uval, (void *)(uintptr_t)uval); 5363 } else if (key_field->flags & HIST_FIELD_FL_SYM_OFFSET) { 5364 uval = *(u64 *)(key + key_field->offset); 5365 seq_printf(m, "%s: [%llx] %-55pS", field_name, 5366 uval, (void *)(uintptr_t)uval); 5367 } else if (key_field->flags & HIST_FIELD_FL_EXECNAME) { 5368 struct hist_elt_data *elt_data = elt->private_data; 5369 char *comm; 5370 5371 if (WARN_ON_ONCE(!elt_data)) 5372 return; 5373 5374 comm = elt_data->comm; 5375 5376 uval = *(u64 *)(key + key_field->offset); 5377 seq_printf(m, "%s: %-16s[%10llu]", field_name, 5378 comm, uval); 5379 } else if (key_field->flags & HIST_FIELD_FL_SYSCALL) { 5380 const char *syscall_name; 5381 5382 uval = *(u64 *)(key + key_field->offset); 5383 syscall_name = get_syscall_name(uval); 5384 if (!syscall_name) 5385 syscall_name = "unknown_syscall"; 5386 5387 seq_printf(m, "%s: %-30s[%3llu]", field_name, 5388 syscall_name, uval); 5389 } else if (key_field->flags & HIST_FIELD_FL_STACKTRACE) { 5390 if (key_field->field) 5391 seq_printf(m, "%s.stacktrace", key_field->field->name); 5392 else 5393 seq_puts(m, "common_stacktrace:\n"); 5394 hist_trigger_stacktrace_print(m, 5395 key + key_field->offset, 5396 HIST_STACKTRACE_DEPTH); 5397 multiline = true; 5398 } else if (key_field->flags & HIST_FIELD_FL_LOG2) { 5399 seq_printf(m, "%s: ~ 2^%-2llu", field_name, 5400 *(u64 *)(key + key_field->offset)); 5401 } else if (key_field->flags & HIST_FIELD_FL_BUCKET) { 5402 unsigned long buckets = key_field->buckets; 5403 uval = *(u64 *)(key + key_field->offset); 5404 seq_printf(m, "%s: ~ %llu-%llu", field_name, 5405 uval, uval + buckets -1); 5406 } else if (key_field->flags & HIST_FIELD_FL_STRING) { 5407 seq_printf(m, "%s: %-50s", field_name, 5408 (char *)(key + key_field->offset)); 5409 } else { 5410 uval = *(u64 *)(key + key_field->offset); 5411 seq_printf(m, "%s: %10llu", field_name, uval); 5412 } 5413 } 5414 5415 if (!multiline) 5416 seq_puts(m, " "); 5417 5418 seq_puts(m, "}"); 5419 } 5420 5421 /* Get the 100 times of the percentage of @val in @total */ 5422 static inline unsigned int __get_percentage(u64 val, u64 total) 5423 { 5424 if (!total) 5425 goto div0; 5426 5427 if (val < (U64_MAX / 10000)) 5428 return (unsigned int)div64_ul(val * 10000, total); 5429 5430 total = div64_u64(total, 10000); 5431 if (!total) 5432 goto div0; 5433 5434 return (unsigned int)div64_ul(val, total); 5435 div0: 5436 return val ? UINT_MAX : 0; 5437 } 5438 5439 #define BAR_CHAR '#' 5440 5441 static inline const char *__fill_bar_str(char *buf, int size, u64 val, u64 max) 5442 { 5443 unsigned int len = __get_percentage(val, max); 5444 int i; 5445 5446 if (len == UINT_MAX) { 5447 snprintf(buf, size, "[ERROR]"); 5448 return buf; 5449 } 5450 5451 len = len * size / 10000; 5452 for (i = 0; i < len && i < size; i++) 5453 buf[i] = BAR_CHAR; 5454 while (i < size) 5455 buf[i++] = ' '; 5456 buf[size] = '\0'; 5457 5458 return buf; 5459 } 5460 5461 struct hist_val_stat { 5462 u64 max; 5463 u64 total; 5464 }; 5465 5466 static void hist_trigger_print_val(struct seq_file *m, unsigned int idx, 5467 const char *field_name, unsigned long flags, 5468 struct hist_val_stat *stats, 5469 struct tracing_map_elt *elt) 5470 { 5471 u64 val = tracing_map_read_sum(elt, idx); 5472 unsigned int pc; 5473 char bar[21]; 5474 5475 if (flags & HIST_FIELD_FL_PERCENT) { 5476 pc = __get_percentage(val, stats[idx].total); 5477 if (pc == UINT_MAX) 5478 seq_printf(m, " %s (%%):[ERROR]", field_name); 5479 else 5480 seq_printf(m, " %s (%%): %3u.%02u", field_name, 5481 pc / 100, pc % 100); 5482 } else if (flags & HIST_FIELD_FL_GRAPH) { 5483 seq_printf(m, " %s: %20s", field_name, 5484 __fill_bar_str(bar, 20, val, stats[idx].max)); 5485 } else if (flags & HIST_FIELD_FL_HEX) { 5486 seq_printf(m, " %s: %10llx", field_name, val); 5487 } else { 5488 seq_printf(m, " %s: %10llu", field_name, val); 5489 } 5490 } 5491 5492 static void hist_trigger_entry_print(struct seq_file *m, 5493 struct hist_trigger_data *hist_data, 5494 struct hist_val_stat *stats, 5495 void *key, 5496 struct tracing_map_elt *elt) 5497 { 5498 const char *field_name; 5499 unsigned int i = HITCOUNT_IDX; 5500 unsigned long flags; 5501 5502 hist_trigger_print_key(m, hist_data, key, elt); 5503 5504 /* At first, show the raw hitcount if !nohitcount */ 5505 if (!hist_data->attrs->no_hitcount) 5506 hist_trigger_print_val(m, i, "hitcount", 0, stats, elt); 5507 5508 for (i = 1; i < hist_data->n_vals; i++) { 5509 field_name = hist_field_name(hist_data->fields[i], 0); 5510 flags = hist_data->fields[i]->flags; 5511 if (flags & HIST_FIELD_FL_VAR || flags & HIST_FIELD_FL_EXPR) 5512 continue; 5513 5514 seq_puts(m, " "); 5515 hist_trigger_print_val(m, i, field_name, flags, stats, elt); 5516 } 5517 5518 print_actions(m, hist_data, elt); 5519 5520 seq_puts(m, "\n"); 5521 } 5522 5523 static int print_entries(struct seq_file *m, 5524 struct hist_trigger_data *hist_data) 5525 { 5526 struct tracing_map_sort_entry **sort_entries = NULL; 5527 struct tracing_map *map = hist_data->map; 5528 int i, j, n_entries; 5529 struct hist_val_stat *stats = NULL; 5530 u64 val; 5531 5532 n_entries = tracing_map_sort_entries(map, hist_data->sort_keys, 5533 hist_data->n_sort_keys, 5534 &sort_entries); 5535 if (n_entries < 0) 5536 return n_entries; 5537 5538 /* Calculate the max and the total for each field if needed. */ 5539 for (j = 0; j < hist_data->n_vals; j++) { 5540 if (!(hist_data->fields[j]->flags & 5541 (HIST_FIELD_FL_PERCENT | HIST_FIELD_FL_GRAPH))) 5542 continue; 5543 if (!stats) { 5544 stats = kcalloc(hist_data->n_vals, sizeof(*stats), 5545 GFP_KERNEL); 5546 if (!stats) { 5547 n_entries = -ENOMEM; 5548 goto out; 5549 } 5550 } 5551 for (i = 0; i < n_entries; i++) { 5552 val = tracing_map_read_sum(sort_entries[i]->elt, j); 5553 stats[j].total += val; 5554 if (stats[j].max < val) 5555 stats[j].max = val; 5556 } 5557 } 5558 5559 for (i = 0; i < n_entries; i++) 5560 hist_trigger_entry_print(m, hist_data, stats, 5561 sort_entries[i]->key, 5562 sort_entries[i]->elt); 5563 5564 kfree(stats); 5565 out: 5566 tracing_map_destroy_sort_entries(sort_entries, n_entries); 5567 5568 return n_entries; 5569 } 5570 5571 static void hist_trigger_show(struct seq_file *m, 5572 struct event_trigger_data *data, int n) 5573 { 5574 struct hist_trigger_data *hist_data; 5575 int n_entries; 5576 5577 if (n > 0) 5578 seq_puts(m, "\n\n"); 5579 5580 seq_puts(m, "# event histogram\n#\n# trigger info: "); 5581 data->ops->print(m, data); 5582 seq_puts(m, "#\n\n"); 5583 5584 hist_data = data->private_data; 5585 n_entries = print_entries(m, hist_data); 5586 if (n_entries < 0) 5587 n_entries = 0; 5588 5589 track_data_snapshot_print(m, hist_data); 5590 5591 seq_printf(m, "\nTotals:\n Hits: %llu\n Entries: %u\n Dropped: %llu\n", 5592 (u64)atomic64_read(&hist_data->map->hits), 5593 n_entries, (u64)atomic64_read(&hist_data->map->drops)); 5594 } 5595 5596 static int hist_show(struct seq_file *m, void *v) 5597 { 5598 struct event_trigger_data *data; 5599 struct trace_event_file *event_file; 5600 int n = 0, ret = 0; 5601 5602 mutex_lock(&event_mutex); 5603 5604 event_file = event_file_file(m->private); 5605 if (unlikely(!event_file)) { 5606 ret = -ENODEV; 5607 goto out_unlock; 5608 } 5609 5610 list_for_each_entry(data, &event_file->triggers, list) { 5611 if (data->cmd_ops->trigger_type == ETT_EVENT_HIST) 5612 hist_trigger_show(m, data, n++); 5613 } 5614 5615 out_unlock: 5616 mutex_unlock(&event_mutex); 5617 5618 return ret; 5619 } 5620 5621 static int event_hist_open(struct inode *inode, struct file *file) 5622 { 5623 int ret; 5624 5625 ret = tracing_open_file_tr(inode, file); 5626 if (ret) 5627 return ret; 5628 5629 /* Clear private_data to avoid warning in single_open() */ 5630 file->private_data = NULL; 5631 return single_open(file, hist_show, file); 5632 } 5633 5634 const struct file_operations event_hist_fops = { 5635 .open = event_hist_open, 5636 .read = seq_read, 5637 .llseek = seq_lseek, 5638 .release = tracing_single_release_file_tr, 5639 }; 5640 5641 #ifdef CONFIG_HIST_TRIGGERS_DEBUG 5642 static void hist_field_debug_show_flags(struct seq_file *m, 5643 unsigned long flags) 5644 { 5645 seq_puts(m, " flags:\n"); 5646 5647 if (flags & HIST_FIELD_FL_KEY) 5648 seq_puts(m, " HIST_FIELD_FL_KEY\n"); 5649 else if (flags & HIST_FIELD_FL_HITCOUNT) 5650 seq_puts(m, " VAL: HIST_FIELD_FL_HITCOUNT\n"); 5651 else if (flags & HIST_FIELD_FL_VAR) 5652 seq_puts(m, " HIST_FIELD_FL_VAR\n"); 5653 else if (flags & HIST_FIELD_FL_VAR_REF) 5654 seq_puts(m, " HIST_FIELD_FL_VAR_REF\n"); 5655 else 5656 seq_puts(m, " VAL: normal u64 value\n"); 5657 5658 if (flags & HIST_FIELD_FL_ALIAS) 5659 seq_puts(m, " HIST_FIELD_FL_ALIAS\n"); 5660 else if (flags & HIST_FIELD_FL_CONST) 5661 seq_puts(m, " HIST_FIELD_FL_CONST\n"); 5662 } 5663 5664 static int hist_field_debug_show(struct seq_file *m, 5665 struct hist_field *field, unsigned long flags) 5666 { 5667 if ((field->flags & flags) != flags) { 5668 seq_printf(m, "ERROR: bad flags - %lx\n", flags); 5669 return -EINVAL; 5670 } 5671 5672 hist_field_debug_show_flags(m, field->flags); 5673 if (field->field) 5674 seq_printf(m, " ftrace_event_field name: %s\n", 5675 field->field->name); 5676 5677 if (field->flags & HIST_FIELD_FL_VAR) { 5678 seq_printf(m, " var.name: %s\n", field->var.name); 5679 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n", 5680 field->var.idx); 5681 } 5682 5683 if (field->flags & HIST_FIELD_FL_CONST) 5684 seq_printf(m, " constant: %llu\n", field->constant); 5685 5686 if (field->flags & HIST_FIELD_FL_ALIAS) 5687 seq_printf(m, " var_ref_idx (into hist_data->var_refs[]): %u\n", 5688 field->var_ref_idx); 5689 5690 if (field->flags & HIST_FIELD_FL_VAR_REF) { 5691 seq_printf(m, " name: %s\n", field->name); 5692 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n", 5693 field->var.idx); 5694 seq_printf(m, " var.hist_data: %p\n", field->var.hist_data); 5695 seq_printf(m, " var_ref_idx (into hist_data->var_refs[]): %u\n", 5696 field->var_ref_idx); 5697 if (field->system) 5698 seq_printf(m, " system: %s\n", field->system); 5699 if (field->event_name) 5700 seq_printf(m, " event_name: %s\n", field->event_name); 5701 } 5702 5703 seq_printf(m, " type: %s\n", field->type); 5704 seq_printf(m, " size: %u\n", field->size); 5705 seq_printf(m, " is_signed: %u\n", field->is_signed); 5706 5707 return 0; 5708 } 5709 5710 static int field_var_debug_show(struct seq_file *m, 5711 struct field_var *field_var, unsigned int i, 5712 bool save_vars) 5713 { 5714 const char *vars_name = save_vars ? "save_vars" : "field_vars"; 5715 struct hist_field *field; 5716 int ret = 0; 5717 5718 seq_printf(m, "\n hist_data->%s[%d]:\n", vars_name, i); 5719 5720 field = field_var->var; 5721 5722 seq_printf(m, "\n %s[%d].var:\n", vars_name, i); 5723 5724 hist_field_debug_show_flags(m, field->flags); 5725 seq_printf(m, " var.name: %s\n", field->var.name); 5726 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n", 5727 field->var.idx); 5728 5729 field = field_var->val; 5730 5731 seq_printf(m, "\n %s[%d].val:\n", vars_name, i); 5732 if (field->field) 5733 seq_printf(m, " ftrace_event_field name: %s\n", 5734 field->field->name); 5735 else { 5736 ret = -EINVAL; 5737 goto out; 5738 } 5739 5740 seq_printf(m, " type: %s\n", field->type); 5741 seq_printf(m, " size: %u\n", field->size); 5742 seq_printf(m, " is_signed: %u\n", field->is_signed); 5743 out: 5744 return ret; 5745 } 5746 5747 static int hist_action_debug_show(struct seq_file *m, 5748 struct action_data *data, int i) 5749 { 5750 int ret = 0; 5751 5752 if (data->handler == HANDLER_ONMAX || 5753 data->handler == HANDLER_ONCHANGE) { 5754 seq_printf(m, "\n hist_data->actions[%d].track_data.var_ref:\n", i); 5755 ret = hist_field_debug_show(m, data->track_data.var_ref, 5756 HIST_FIELD_FL_VAR_REF); 5757 if (ret) 5758 goto out; 5759 5760 seq_printf(m, "\n hist_data->actions[%d].track_data.track_var:\n", i); 5761 ret = hist_field_debug_show(m, data->track_data.track_var, 5762 HIST_FIELD_FL_VAR); 5763 if (ret) 5764 goto out; 5765 } 5766 5767 if (data->handler == HANDLER_ONMATCH) { 5768 seq_printf(m, "\n hist_data->actions[%d].match_data.event_system: %s\n", 5769 i, data->match_data.event_system); 5770 seq_printf(m, " hist_data->actions[%d].match_data.event: %s\n", 5771 i, data->match_data.event); 5772 } 5773 out: 5774 return ret; 5775 } 5776 5777 static int hist_actions_debug_show(struct seq_file *m, 5778 struct hist_trigger_data *hist_data) 5779 { 5780 int i, ret = 0; 5781 5782 if (hist_data->n_actions) 5783 seq_puts(m, "\n action tracking variables (for onmax()/onchange()/onmatch()):\n"); 5784 5785 for (i = 0; i < hist_data->n_actions; i++) { 5786 struct action_data *action = hist_data->actions[i]; 5787 5788 ret = hist_action_debug_show(m, action, i); 5789 if (ret) 5790 goto out; 5791 } 5792 5793 if (hist_data->n_save_vars) 5794 seq_puts(m, "\n save action variables (save() params):\n"); 5795 5796 for (i = 0; i < hist_data->n_save_vars; i++) { 5797 ret = field_var_debug_show(m, hist_data->save_vars[i], i, true); 5798 if (ret) 5799 goto out; 5800 } 5801 out: 5802 return ret; 5803 } 5804 5805 static void hist_trigger_debug_show(struct seq_file *m, 5806 struct event_trigger_data *data, int n) 5807 { 5808 struct hist_trigger_data *hist_data; 5809 int i, ret; 5810 5811 if (n > 0) 5812 seq_puts(m, "\n\n"); 5813 5814 seq_puts(m, "# event histogram\n#\n# trigger info: "); 5815 data->ops->print(m, data); 5816 seq_puts(m, "#\n\n"); 5817 5818 hist_data = data->private_data; 5819 5820 seq_printf(m, "hist_data: %p\n\n", hist_data); 5821 seq_printf(m, " n_vals: %u\n", hist_data->n_vals); 5822 seq_printf(m, " n_keys: %u\n", hist_data->n_keys); 5823 seq_printf(m, " n_fields: %u\n", hist_data->n_fields); 5824 5825 seq_puts(m, "\n val fields:\n\n"); 5826 5827 seq_puts(m, " hist_data->fields[0]:\n"); 5828 ret = hist_field_debug_show(m, hist_data->fields[0], 5829 HIST_FIELD_FL_HITCOUNT); 5830 if (ret) 5831 return; 5832 5833 for (i = 1; i < hist_data->n_vals; i++) { 5834 seq_printf(m, "\n hist_data->fields[%d]:\n", i); 5835 ret = hist_field_debug_show(m, hist_data->fields[i], 0); 5836 if (ret) 5837 return; 5838 } 5839 5840 seq_puts(m, "\n key fields:\n"); 5841 5842 for (i = hist_data->n_vals; i < hist_data->n_fields; i++) { 5843 seq_printf(m, "\n hist_data->fields[%d]:\n", i); 5844 ret = hist_field_debug_show(m, hist_data->fields[i], 5845 HIST_FIELD_FL_KEY); 5846 if (ret) 5847 return; 5848 } 5849 5850 if (hist_data->n_var_refs) 5851 seq_puts(m, "\n variable reference fields:\n"); 5852 5853 for (i = 0; i < hist_data->n_var_refs; i++) { 5854 seq_printf(m, "\n hist_data->var_refs[%d]:\n", i); 5855 ret = hist_field_debug_show(m, hist_data->var_refs[i], 5856 HIST_FIELD_FL_VAR_REF); 5857 if (ret) 5858 return; 5859 } 5860 5861 if (hist_data->n_field_vars) 5862 seq_puts(m, "\n field variables:\n"); 5863 5864 for (i = 0; i < hist_data->n_field_vars; i++) { 5865 ret = field_var_debug_show(m, hist_data->field_vars[i], i, false); 5866 if (ret) 5867 return; 5868 } 5869 5870 ret = hist_actions_debug_show(m, hist_data); 5871 if (ret) 5872 return; 5873 } 5874 5875 static int hist_debug_show(struct seq_file *m, void *v) 5876 { 5877 struct event_trigger_data *data; 5878 struct trace_event_file *event_file; 5879 int n = 0, ret = 0; 5880 5881 mutex_lock(&event_mutex); 5882 5883 event_file = event_file_file(m->private); 5884 if (unlikely(!event_file)) { 5885 ret = -ENODEV; 5886 goto out_unlock; 5887 } 5888 5889 list_for_each_entry(data, &event_file->triggers, list) { 5890 if (data->cmd_ops->trigger_type == ETT_EVENT_HIST) 5891 hist_trigger_debug_show(m, data, n++); 5892 } 5893 5894 out_unlock: 5895 mutex_unlock(&event_mutex); 5896 5897 return ret; 5898 } 5899 5900 static int event_hist_debug_open(struct inode *inode, struct file *file) 5901 { 5902 int ret; 5903 5904 ret = tracing_open_file_tr(inode, file); 5905 if (ret) 5906 return ret; 5907 5908 /* Clear private_data to avoid warning in single_open() */ 5909 file->private_data = NULL; 5910 return single_open(file, hist_debug_show, file); 5911 } 5912 5913 const struct file_operations event_hist_debug_fops = { 5914 .open = event_hist_debug_open, 5915 .read = seq_read, 5916 .llseek = seq_lseek, 5917 .release = tracing_single_release_file_tr, 5918 }; 5919 #endif 5920 5921 static void hist_field_print(struct seq_file *m, struct hist_field *hist_field) 5922 { 5923 const char *field_name = hist_field_name(hist_field, 0); 5924 5925 if (hist_field->var.name) 5926 seq_printf(m, "%s=", hist_field->var.name); 5927 5928 if (hist_field->flags & HIST_FIELD_FL_CPU) 5929 seq_puts(m, "common_cpu"); 5930 else if (hist_field->flags & HIST_FIELD_FL_CONST) 5931 seq_printf(m, "%llu", hist_field->constant); 5932 else if (field_name) { 5933 if (hist_field->flags & HIST_FIELD_FL_VAR_REF || 5934 hist_field->flags & HIST_FIELD_FL_ALIAS) 5935 seq_putc(m, '$'); 5936 seq_printf(m, "%s", field_name); 5937 } else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP) 5938 seq_puts(m, "common_timestamp"); 5939 5940 if (hist_field->flags) { 5941 if (!(hist_field->flags & HIST_FIELD_FL_VAR_REF) && 5942 !(hist_field->flags & HIST_FIELD_FL_EXPR) && 5943 !(hist_field->flags & HIST_FIELD_FL_STACKTRACE)) { 5944 const char *flags = get_hist_field_flags(hist_field); 5945 5946 if (flags) 5947 seq_printf(m, ".%s", flags); 5948 } 5949 } 5950 if (hist_field->buckets) 5951 seq_printf(m, "=%ld", hist_field->buckets); 5952 } 5953 5954 static int event_hist_trigger_print(struct seq_file *m, 5955 struct event_trigger_data *data) 5956 { 5957 struct hist_trigger_data *hist_data = data->private_data; 5958 struct hist_field *field; 5959 bool have_var = false; 5960 bool show_val = false; 5961 unsigned int i; 5962 5963 seq_puts(m, HIST_PREFIX); 5964 5965 if (data->name) 5966 seq_printf(m, "%s:", data->name); 5967 5968 seq_puts(m, "keys="); 5969 5970 for_each_hist_key_field(i, hist_data) { 5971 field = hist_data->fields[i]; 5972 5973 if (i > hist_data->n_vals) 5974 seq_puts(m, ","); 5975 5976 if (field->flags & HIST_FIELD_FL_STACKTRACE) { 5977 if (field->field) 5978 seq_printf(m, "%s.stacktrace", field->field->name); 5979 else 5980 seq_puts(m, "common_stacktrace"); 5981 } else 5982 hist_field_print(m, field); 5983 } 5984 5985 seq_puts(m, ":vals="); 5986 5987 for_each_hist_val_field(i, hist_data) { 5988 field = hist_data->fields[i]; 5989 if (field->flags & HIST_FIELD_FL_VAR) { 5990 have_var = true; 5991 continue; 5992 } 5993 5994 if (i == HITCOUNT_IDX) { 5995 if (hist_data->attrs->no_hitcount) 5996 continue; 5997 seq_puts(m, "hitcount"); 5998 } else { 5999 if (show_val) 6000 seq_puts(m, ","); 6001 hist_field_print(m, field); 6002 } 6003 show_val = true; 6004 } 6005 6006 if (have_var) { 6007 unsigned int n = 0; 6008 6009 seq_puts(m, ":"); 6010 6011 for_each_hist_val_field(i, hist_data) { 6012 field = hist_data->fields[i]; 6013 6014 if (field->flags & HIST_FIELD_FL_VAR) { 6015 if (n++) 6016 seq_puts(m, ","); 6017 hist_field_print(m, field); 6018 } 6019 } 6020 } 6021 6022 seq_puts(m, ":sort="); 6023 6024 for (i = 0; i < hist_data->n_sort_keys; i++) { 6025 struct tracing_map_sort_key *sort_key; 6026 unsigned int idx, first_key_idx; 6027 6028 /* skip VAR vals */ 6029 first_key_idx = hist_data->n_vals - hist_data->n_vars; 6030 6031 sort_key = &hist_data->sort_keys[i]; 6032 idx = sort_key->field_idx; 6033 6034 if (WARN_ON(idx >= HIST_FIELDS_MAX)) 6035 return -EINVAL; 6036 6037 if (i > 0) 6038 seq_puts(m, ","); 6039 6040 if (idx == HITCOUNT_IDX) 6041 seq_puts(m, "hitcount"); 6042 else { 6043 if (idx >= first_key_idx) 6044 idx += hist_data->n_vars; 6045 hist_field_print(m, hist_data->fields[idx]); 6046 } 6047 6048 if (sort_key->descending) 6049 seq_puts(m, ".descending"); 6050 } 6051 seq_printf(m, ":size=%u", (1 << hist_data->map->map_bits)); 6052 if (hist_data->enable_timestamps) 6053 seq_printf(m, ":clock=%s", hist_data->attrs->clock); 6054 if (hist_data->attrs->no_hitcount) 6055 seq_puts(m, ":nohitcount"); 6056 6057 print_actions_spec(m, hist_data); 6058 6059 if (data->filter_str) 6060 seq_printf(m, " if %s", data->filter_str); 6061 6062 if (data->paused) 6063 seq_puts(m, " [paused]"); 6064 else 6065 seq_puts(m, " [active]"); 6066 6067 seq_putc(m, '\n'); 6068 6069 return 0; 6070 } 6071 6072 static int event_hist_trigger_init(struct event_trigger_data *data) 6073 { 6074 struct hist_trigger_data *hist_data = data->private_data; 6075 6076 if (!data->ref && hist_data->attrs->name) 6077 save_named_trigger(hist_data->attrs->name, data); 6078 6079 data->ref++; 6080 6081 return 0; 6082 } 6083 6084 static void unregister_field_var_hists(struct hist_trigger_data *hist_data) 6085 { 6086 struct trace_event_file *file; 6087 unsigned int i; 6088 char *cmd; 6089 int ret; 6090 6091 for (i = 0; i < hist_data->n_field_var_hists; i++) { 6092 file = hist_data->field_var_hists[i]->hist_data->event_file; 6093 cmd = hist_data->field_var_hists[i]->cmd; 6094 ret = event_hist_trigger_parse(&trigger_hist_cmd, file, 6095 "!hist", "hist", cmd); 6096 WARN_ON_ONCE(ret < 0); 6097 } 6098 } 6099 6100 static void event_hist_trigger_free(struct event_trigger_data *data) 6101 { 6102 struct hist_trigger_data *hist_data = data->private_data; 6103 6104 if (WARN_ON_ONCE(data->ref <= 0)) 6105 return; 6106 6107 data->ref--; 6108 if (!data->ref) { 6109 if (data->name) 6110 del_named_trigger(data); 6111 6112 trigger_data_free(data); 6113 6114 remove_hist_vars(hist_data); 6115 6116 unregister_field_var_hists(hist_data); 6117 6118 destroy_hist_data(hist_data); 6119 } 6120 } 6121 6122 static struct event_trigger_ops event_hist_trigger_ops = { 6123 .trigger = event_hist_trigger, 6124 .print = event_hist_trigger_print, 6125 .init = event_hist_trigger_init, 6126 .free = event_hist_trigger_free, 6127 }; 6128 6129 static int event_hist_trigger_named_init(struct event_trigger_data *data) 6130 { 6131 data->ref++; 6132 6133 save_named_trigger(data->named_data->name, data); 6134 6135 event_hist_trigger_init(data->named_data); 6136 6137 return 0; 6138 } 6139 6140 static void event_hist_trigger_named_free(struct event_trigger_data *data) 6141 { 6142 if (WARN_ON_ONCE(data->ref <= 0)) 6143 return; 6144 6145 event_hist_trigger_free(data->named_data); 6146 6147 data->ref--; 6148 if (!data->ref) { 6149 del_named_trigger(data); 6150 trigger_data_free(data); 6151 } 6152 } 6153 6154 static struct event_trigger_ops event_hist_trigger_named_ops = { 6155 .trigger = event_hist_trigger, 6156 .print = event_hist_trigger_print, 6157 .init = event_hist_trigger_named_init, 6158 .free = event_hist_trigger_named_free, 6159 }; 6160 6161 static struct event_trigger_ops *event_hist_get_trigger_ops(char *cmd, 6162 char *param) 6163 { 6164 return &event_hist_trigger_ops; 6165 } 6166 6167 static void hist_clear(struct event_trigger_data *data) 6168 { 6169 struct hist_trigger_data *hist_data = data->private_data; 6170 6171 if (data->name) 6172 pause_named_trigger(data); 6173 6174 tracepoint_synchronize_unregister(); 6175 6176 tracing_map_clear(hist_data->map); 6177 6178 if (data->name) 6179 unpause_named_trigger(data); 6180 } 6181 6182 static bool compatible_field(struct ftrace_event_field *field, 6183 struct ftrace_event_field *test_field) 6184 { 6185 if (field == test_field) 6186 return true; 6187 if (field == NULL || test_field == NULL) 6188 return false; 6189 if (strcmp(field->name, test_field->name) != 0) 6190 return false; 6191 if (strcmp(field->type, test_field->type) != 0) 6192 return false; 6193 if (field->size != test_field->size) 6194 return false; 6195 if (field->is_signed != test_field->is_signed) 6196 return false; 6197 6198 return true; 6199 } 6200 6201 static bool hist_trigger_match(struct event_trigger_data *data, 6202 struct event_trigger_data *data_test, 6203 struct event_trigger_data *named_data, 6204 bool ignore_filter) 6205 { 6206 struct tracing_map_sort_key *sort_key, *sort_key_test; 6207 struct hist_trigger_data *hist_data, *hist_data_test; 6208 struct hist_field *key_field, *key_field_test; 6209 unsigned int i; 6210 6211 if (named_data && (named_data != data_test) && 6212 (named_data != data_test->named_data)) 6213 return false; 6214 6215 if (!named_data && is_named_trigger(data_test)) 6216 return false; 6217 6218 hist_data = data->private_data; 6219 hist_data_test = data_test->private_data; 6220 6221 if (hist_data->n_vals != hist_data_test->n_vals || 6222 hist_data->n_fields != hist_data_test->n_fields || 6223 hist_data->n_sort_keys != hist_data_test->n_sort_keys) 6224 return false; 6225 6226 if (!ignore_filter) { 6227 if ((data->filter_str && !data_test->filter_str) || 6228 (!data->filter_str && data_test->filter_str)) 6229 return false; 6230 } 6231 6232 for_each_hist_field(i, hist_data) { 6233 key_field = hist_data->fields[i]; 6234 key_field_test = hist_data_test->fields[i]; 6235 6236 if (key_field->flags != key_field_test->flags) 6237 return false; 6238 if (!compatible_field(key_field->field, key_field_test->field)) 6239 return false; 6240 if (key_field->offset != key_field_test->offset) 6241 return false; 6242 if (key_field->size != key_field_test->size) 6243 return false; 6244 if (key_field->is_signed != key_field_test->is_signed) 6245 return false; 6246 if (!!key_field->var.name != !!key_field_test->var.name) 6247 return false; 6248 if (key_field->var.name && 6249 strcmp(key_field->var.name, key_field_test->var.name) != 0) 6250 return false; 6251 } 6252 6253 for (i = 0; i < hist_data->n_sort_keys; i++) { 6254 sort_key = &hist_data->sort_keys[i]; 6255 sort_key_test = &hist_data_test->sort_keys[i]; 6256 6257 if (sort_key->field_idx != sort_key_test->field_idx || 6258 sort_key->descending != sort_key_test->descending) 6259 return false; 6260 } 6261 6262 if (!ignore_filter && data->filter_str && 6263 (strcmp(data->filter_str, data_test->filter_str) != 0)) 6264 return false; 6265 6266 if (!actions_match(hist_data, hist_data_test)) 6267 return false; 6268 6269 return true; 6270 } 6271 6272 static bool existing_hist_update_only(char *glob, 6273 struct event_trigger_data *data, 6274 struct trace_event_file *file) 6275 { 6276 struct hist_trigger_data *hist_data = data->private_data; 6277 struct event_trigger_data *test, *named_data = NULL; 6278 bool updated = false; 6279 6280 if (!hist_data->attrs->pause && !hist_data->attrs->cont && 6281 !hist_data->attrs->clear) 6282 goto out; 6283 6284 if (hist_data->attrs->name) { 6285 named_data = find_named_trigger(hist_data->attrs->name); 6286 if (named_data) { 6287 if (!hist_trigger_match(data, named_data, named_data, 6288 true)) 6289 goto out; 6290 } 6291 } 6292 6293 if (hist_data->attrs->name && !named_data) 6294 goto out; 6295 6296 list_for_each_entry(test, &file->triggers, list) { 6297 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6298 if (!hist_trigger_match(data, test, named_data, false)) 6299 continue; 6300 if (hist_data->attrs->pause) 6301 test->paused = true; 6302 else if (hist_data->attrs->cont) 6303 test->paused = false; 6304 else if (hist_data->attrs->clear) 6305 hist_clear(test); 6306 updated = true; 6307 goto out; 6308 } 6309 } 6310 out: 6311 return updated; 6312 } 6313 6314 static int hist_register_trigger(char *glob, 6315 struct event_trigger_data *data, 6316 struct trace_event_file *file) 6317 { 6318 struct hist_trigger_data *hist_data = data->private_data; 6319 struct event_trigger_data *test, *named_data = NULL; 6320 struct trace_array *tr = file->tr; 6321 int ret = 0; 6322 6323 if (hist_data->attrs->name) { 6324 named_data = find_named_trigger(hist_data->attrs->name); 6325 if (named_data) { 6326 if (!hist_trigger_match(data, named_data, named_data, 6327 true)) { 6328 hist_err(tr, HIST_ERR_NAMED_MISMATCH, errpos(hist_data->attrs->name)); 6329 ret = -EINVAL; 6330 goto out; 6331 } 6332 } 6333 } 6334 6335 if (hist_data->attrs->name && !named_data) 6336 goto new; 6337 6338 lockdep_assert_held(&event_mutex); 6339 6340 list_for_each_entry(test, &file->triggers, list) { 6341 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6342 if (hist_trigger_match(data, test, named_data, false)) { 6343 hist_err(tr, HIST_ERR_TRIGGER_EEXIST, 0); 6344 ret = -EEXIST; 6345 goto out; 6346 } 6347 } 6348 } 6349 new: 6350 if (hist_data->attrs->cont || hist_data->attrs->clear) { 6351 hist_err(tr, HIST_ERR_TRIGGER_ENOENT_CLEAR, 0); 6352 ret = -ENOENT; 6353 goto out; 6354 } 6355 6356 if (hist_data->attrs->pause) 6357 data->paused = true; 6358 6359 if (named_data) { 6360 data->private_data = named_data->private_data; 6361 set_named_trigger_data(data, named_data); 6362 data->ops = &event_hist_trigger_named_ops; 6363 } 6364 6365 if (data->ops->init) { 6366 ret = data->ops->init(data); 6367 if (ret < 0) 6368 goto out; 6369 } 6370 6371 if (hist_data->enable_timestamps) { 6372 char *clock = hist_data->attrs->clock; 6373 6374 ret = tracing_set_clock(file->tr, hist_data->attrs->clock); 6375 if (ret) { 6376 hist_err(tr, HIST_ERR_SET_CLOCK_FAIL, errpos(clock)); 6377 goto out; 6378 } 6379 6380 tracing_set_filter_buffering(file->tr, true); 6381 } 6382 6383 if (named_data) 6384 destroy_hist_data(hist_data); 6385 out: 6386 return ret; 6387 } 6388 6389 static int hist_trigger_enable(struct event_trigger_data *data, 6390 struct trace_event_file *file) 6391 { 6392 int ret = 0; 6393 6394 list_add_tail_rcu(&data->list, &file->triggers); 6395 6396 update_cond_flag(file); 6397 6398 if (trace_event_trigger_enable_disable(file, 1) < 0) { 6399 list_del_rcu(&data->list); 6400 update_cond_flag(file); 6401 ret--; 6402 } 6403 6404 return ret; 6405 } 6406 6407 static bool have_hist_trigger_match(struct event_trigger_data *data, 6408 struct trace_event_file *file) 6409 { 6410 struct hist_trigger_data *hist_data = data->private_data; 6411 struct event_trigger_data *test, *named_data = NULL; 6412 bool match = false; 6413 6414 lockdep_assert_held(&event_mutex); 6415 6416 if (hist_data->attrs->name) 6417 named_data = find_named_trigger(hist_data->attrs->name); 6418 6419 list_for_each_entry(test, &file->triggers, list) { 6420 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6421 if (hist_trigger_match(data, test, named_data, false)) { 6422 match = true; 6423 break; 6424 } 6425 } 6426 } 6427 6428 return match; 6429 } 6430 6431 static bool hist_trigger_check_refs(struct event_trigger_data *data, 6432 struct trace_event_file *file) 6433 { 6434 struct hist_trigger_data *hist_data = data->private_data; 6435 struct event_trigger_data *test, *named_data = NULL; 6436 6437 lockdep_assert_held(&event_mutex); 6438 6439 if (hist_data->attrs->name) 6440 named_data = find_named_trigger(hist_data->attrs->name); 6441 6442 list_for_each_entry(test, &file->triggers, list) { 6443 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6444 if (!hist_trigger_match(data, test, named_data, false)) 6445 continue; 6446 hist_data = test->private_data; 6447 if (check_var_refs(hist_data)) 6448 return true; 6449 break; 6450 } 6451 } 6452 6453 return false; 6454 } 6455 6456 static void hist_unregister_trigger(char *glob, 6457 struct event_trigger_data *data, 6458 struct trace_event_file *file) 6459 { 6460 struct event_trigger_data *test = NULL, *iter, *named_data = NULL; 6461 struct hist_trigger_data *hist_data = data->private_data; 6462 6463 lockdep_assert_held(&event_mutex); 6464 6465 if (hist_data->attrs->name) 6466 named_data = find_named_trigger(hist_data->attrs->name); 6467 6468 list_for_each_entry(iter, &file->triggers, list) { 6469 if (iter->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6470 if (!hist_trigger_match(data, iter, named_data, false)) 6471 continue; 6472 test = iter; 6473 list_del_rcu(&test->list); 6474 trace_event_trigger_enable_disable(file, 0); 6475 update_cond_flag(file); 6476 break; 6477 } 6478 } 6479 6480 if (test && test->ops->free) 6481 test->ops->free(test); 6482 6483 if (hist_data->enable_timestamps) { 6484 if (!hist_data->remove || test) 6485 tracing_set_filter_buffering(file->tr, false); 6486 } 6487 } 6488 6489 static bool hist_file_check_refs(struct trace_event_file *file) 6490 { 6491 struct hist_trigger_data *hist_data; 6492 struct event_trigger_data *test; 6493 6494 lockdep_assert_held(&event_mutex); 6495 6496 list_for_each_entry(test, &file->triggers, list) { 6497 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6498 hist_data = test->private_data; 6499 if (check_var_refs(hist_data)) 6500 return true; 6501 } 6502 } 6503 6504 return false; 6505 } 6506 6507 static void hist_unreg_all(struct trace_event_file *file) 6508 { 6509 struct event_trigger_data *test, *n; 6510 struct hist_trigger_data *hist_data; 6511 struct synth_event *se; 6512 const char *se_name; 6513 6514 lockdep_assert_held(&event_mutex); 6515 6516 if (hist_file_check_refs(file)) 6517 return; 6518 6519 list_for_each_entry_safe(test, n, &file->triggers, list) { 6520 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6521 hist_data = test->private_data; 6522 list_del_rcu(&test->list); 6523 trace_event_trigger_enable_disable(file, 0); 6524 6525 se_name = trace_event_name(file->event_call); 6526 se = find_synth_event(se_name); 6527 if (se) 6528 se->ref--; 6529 6530 update_cond_flag(file); 6531 if (hist_data->enable_timestamps) 6532 tracing_set_filter_buffering(file->tr, false); 6533 if (test->ops->free) 6534 test->ops->free(test); 6535 } 6536 } 6537 } 6538 6539 static int event_hist_trigger_parse(struct event_command *cmd_ops, 6540 struct trace_event_file *file, 6541 char *glob, char *cmd, 6542 char *param_and_filter) 6543 { 6544 unsigned int hist_trigger_bits = TRACING_MAP_BITS_DEFAULT; 6545 struct event_trigger_data *trigger_data; 6546 struct hist_trigger_attrs *attrs; 6547 struct hist_trigger_data *hist_data; 6548 char *param, *filter, *p, *start; 6549 struct synth_event *se; 6550 const char *se_name; 6551 bool remove; 6552 int ret = 0; 6553 6554 lockdep_assert_held(&event_mutex); 6555 6556 if (WARN_ON(!glob)) 6557 return -EINVAL; 6558 6559 if (glob[0]) { 6560 hist_err_clear(); 6561 last_cmd_set(file, param_and_filter); 6562 } 6563 6564 remove = event_trigger_check_remove(glob); 6565 6566 if (event_trigger_empty_param(param_and_filter)) 6567 return -EINVAL; 6568 6569 /* 6570 * separate the trigger from the filter (k:v [if filter]) 6571 * allowing for whitespace in the trigger 6572 */ 6573 p = param = param_and_filter; 6574 do { 6575 p = strstr(p, "if"); 6576 if (!p) 6577 break; 6578 if (p == param_and_filter) 6579 return -EINVAL; 6580 if (*(p - 1) != ' ' && *(p - 1) != '\t') { 6581 p++; 6582 continue; 6583 } 6584 if (p >= param_and_filter + strlen(param_and_filter) - (sizeof("if") - 1) - 1) 6585 return -EINVAL; 6586 if (*(p + sizeof("if") - 1) != ' ' && *(p + sizeof("if") - 1) != '\t') { 6587 p++; 6588 continue; 6589 } 6590 break; 6591 } while (1); 6592 6593 if (!p) 6594 filter = NULL; 6595 else { 6596 *(p - 1) = '\0'; 6597 filter = strstrip(p); 6598 param = strstrip(param); 6599 } 6600 6601 /* 6602 * To simplify arithmetic expression parsing, replace occurrences of 6603 * '.sym-offset' modifier with '.symXoffset' 6604 */ 6605 start = strstr(param, ".sym-offset"); 6606 while (start) { 6607 *(start + 4) = 'X'; 6608 start = strstr(start + 11, ".sym-offset"); 6609 } 6610 6611 attrs = parse_hist_trigger_attrs(file->tr, param); 6612 if (IS_ERR(attrs)) 6613 return PTR_ERR(attrs); 6614 6615 if (attrs->map_bits) 6616 hist_trigger_bits = attrs->map_bits; 6617 6618 hist_data = create_hist_data(hist_trigger_bits, attrs, file, remove); 6619 if (IS_ERR(hist_data)) { 6620 destroy_hist_trigger_attrs(attrs); 6621 return PTR_ERR(hist_data); 6622 } 6623 6624 trigger_data = event_trigger_alloc(cmd_ops, cmd, param, hist_data); 6625 if (!trigger_data) { 6626 ret = -ENOMEM; 6627 goto out_free; 6628 } 6629 6630 ret = event_trigger_set_filter(cmd_ops, file, filter, trigger_data); 6631 if (ret < 0) 6632 goto out_free; 6633 6634 if (remove) { 6635 if (!have_hist_trigger_match(trigger_data, file)) 6636 goto out_free; 6637 6638 if (hist_trigger_check_refs(trigger_data, file)) { 6639 ret = -EBUSY; 6640 goto out_free; 6641 } 6642 6643 event_trigger_unregister(cmd_ops, file, glob+1, trigger_data); 6644 se_name = trace_event_name(file->event_call); 6645 se = find_synth_event(se_name); 6646 if (se) 6647 se->ref--; 6648 ret = 0; 6649 goto out_free; 6650 } 6651 6652 if (existing_hist_update_only(glob, trigger_data, file)) 6653 goto out_free; 6654 6655 ret = event_trigger_register(cmd_ops, file, glob, trigger_data); 6656 if (ret < 0) 6657 goto out_free; 6658 6659 if (get_named_trigger_data(trigger_data)) 6660 goto enable; 6661 6662 ret = create_actions(hist_data); 6663 if (ret) 6664 goto out_unreg; 6665 6666 if (has_hist_vars(hist_data) || hist_data->n_var_refs) { 6667 ret = save_hist_vars(hist_data); 6668 if (ret) 6669 goto out_unreg; 6670 } 6671 6672 ret = tracing_map_init(hist_data->map); 6673 if (ret) 6674 goto out_unreg; 6675 enable: 6676 ret = hist_trigger_enable(trigger_data, file); 6677 if (ret) 6678 goto out_unreg; 6679 6680 se_name = trace_event_name(file->event_call); 6681 se = find_synth_event(se_name); 6682 if (se) 6683 se->ref++; 6684 out: 6685 if (ret == 0 && glob[0]) 6686 hist_err_clear(); 6687 6688 return ret; 6689 out_unreg: 6690 event_trigger_unregister(cmd_ops, file, glob+1, trigger_data); 6691 out_free: 6692 event_trigger_reset_filter(cmd_ops, trigger_data); 6693 6694 remove_hist_vars(hist_data); 6695 6696 kfree(trigger_data); 6697 6698 destroy_hist_data(hist_data); 6699 goto out; 6700 } 6701 6702 static struct event_command trigger_hist_cmd = { 6703 .name = "hist", 6704 .trigger_type = ETT_EVENT_HIST, 6705 .flags = EVENT_CMD_FL_NEEDS_REC, 6706 .parse = event_hist_trigger_parse, 6707 .reg = hist_register_trigger, 6708 .unreg = hist_unregister_trigger, 6709 .unreg_all = hist_unreg_all, 6710 .get_trigger_ops = event_hist_get_trigger_ops, 6711 .set_filter = set_trigger_filter, 6712 }; 6713 6714 __init int register_trigger_hist_cmd(void) 6715 { 6716 int ret; 6717 6718 ret = register_event_command(&trigger_hist_cmd); 6719 WARN_ON(ret < 0); 6720 6721 return ret; 6722 } 6723 6724 static void 6725 hist_enable_trigger(struct event_trigger_data *data, 6726 struct trace_buffer *buffer, void *rec, 6727 struct ring_buffer_event *event) 6728 { 6729 struct enable_trigger_data *enable_data = data->private_data; 6730 struct event_trigger_data *test; 6731 6732 list_for_each_entry_rcu(test, &enable_data->file->triggers, list, 6733 lockdep_is_held(&event_mutex)) { 6734 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6735 if (enable_data->enable) 6736 test->paused = false; 6737 else 6738 test->paused = true; 6739 } 6740 } 6741 } 6742 6743 static void 6744 hist_enable_count_trigger(struct event_trigger_data *data, 6745 struct trace_buffer *buffer, void *rec, 6746 struct ring_buffer_event *event) 6747 { 6748 if (!data->count) 6749 return; 6750 6751 if (data->count != -1) 6752 (data->count)--; 6753 6754 hist_enable_trigger(data, buffer, rec, event); 6755 } 6756 6757 static struct event_trigger_ops hist_enable_trigger_ops = { 6758 .trigger = hist_enable_trigger, 6759 .print = event_enable_trigger_print, 6760 .init = event_trigger_init, 6761 .free = event_enable_trigger_free, 6762 }; 6763 6764 static struct event_trigger_ops hist_enable_count_trigger_ops = { 6765 .trigger = hist_enable_count_trigger, 6766 .print = event_enable_trigger_print, 6767 .init = event_trigger_init, 6768 .free = event_enable_trigger_free, 6769 }; 6770 6771 static struct event_trigger_ops hist_disable_trigger_ops = { 6772 .trigger = hist_enable_trigger, 6773 .print = event_enable_trigger_print, 6774 .init = event_trigger_init, 6775 .free = event_enable_trigger_free, 6776 }; 6777 6778 static struct event_trigger_ops hist_disable_count_trigger_ops = { 6779 .trigger = hist_enable_count_trigger, 6780 .print = event_enable_trigger_print, 6781 .init = event_trigger_init, 6782 .free = event_enable_trigger_free, 6783 }; 6784 6785 static struct event_trigger_ops * 6786 hist_enable_get_trigger_ops(char *cmd, char *param) 6787 { 6788 struct event_trigger_ops *ops; 6789 bool enable; 6790 6791 enable = (strcmp(cmd, ENABLE_HIST_STR) == 0); 6792 6793 if (enable) 6794 ops = param ? &hist_enable_count_trigger_ops : 6795 &hist_enable_trigger_ops; 6796 else 6797 ops = param ? &hist_disable_count_trigger_ops : 6798 &hist_disable_trigger_ops; 6799 6800 return ops; 6801 } 6802 6803 static void hist_enable_unreg_all(struct trace_event_file *file) 6804 { 6805 struct event_trigger_data *test, *n; 6806 6807 list_for_each_entry_safe(test, n, &file->triggers, list) { 6808 if (test->cmd_ops->trigger_type == ETT_HIST_ENABLE) { 6809 list_del_rcu(&test->list); 6810 update_cond_flag(file); 6811 trace_event_trigger_enable_disable(file, 0); 6812 if (test->ops->free) 6813 test->ops->free(test); 6814 } 6815 } 6816 } 6817 6818 static struct event_command trigger_hist_enable_cmd = { 6819 .name = ENABLE_HIST_STR, 6820 .trigger_type = ETT_HIST_ENABLE, 6821 .parse = event_enable_trigger_parse, 6822 .reg = event_enable_register_trigger, 6823 .unreg = event_enable_unregister_trigger, 6824 .unreg_all = hist_enable_unreg_all, 6825 .get_trigger_ops = hist_enable_get_trigger_ops, 6826 .set_filter = set_trigger_filter, 6827 }; 6828 6829 static struct event_command trigger_hist_disable_cmd = { 6830 .name = DISABLE_HIST_STR, 6831 .trigger_type = ETT_HIST_ENABLE, 6832 .parse = event_enable_trigger_parse, 6833 .reg = event_enable_register_trigger, 6834 .unreg = event_enable_unregister_trigger, 6835 .unreg_all = hist_enable_unreg_all, 6836 .get_trigger_ops = hist_enable_get_trigger_ops, 6837 .set_filter = set_trigger_filter, 6838 }; 6839 6840 static __init void unregister_trigger_hist_enable_disable_cmds(void) 6841 { 6842 unregister_event_command(&trigger_hist_enable_cmd); 6843 unregister_event_command(&trigger_hist_disable_cmd); 6844 } 6845 6846 __init int register_trigger_hist_enable_disable_cmds(void) 6847 { 6848 int ret; 6849 6850 ret = register_event_command(&trigger_hist_enable_cmd); 6851 if (WARN_ON(ret < 0)) 6852 return ret; 6853 ret = register_event_command(&trigger_hist_disable_cmd); 6854 if (WARN_ON(ret < 0)) 6855 unregister_trigger_hist_enable_disable_cmds(); 6856 6857 return ret; 6858 } 6859