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