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 hist_field->size = hist_field->operands[0]->size; 1992 hist_field->type = kstrdup_const(hist_field->operands[0]->type, GFP_KERNEL); 1993 if (!hist_field->type) 1994 goto free; 1995 goto out; 1996 } 1997 1998 if (flags & HIST_FIELD_FL_TIMESTAMP) { 1999 hist_field->fn_num = HIST_FIELD_FN_TIMESTAMP; 2000 hist_field->size = sizeof(u64); 2001 hist_field->type = "u64"; 2002 goto out; 2003 } 2004 2005 if (flags & HIST_FIELD_FL_CPU) { 2006 hist_field->fn_num = HIST_FIELD_FN_CPU; 2007 hist_field->size = sizeof(int); 2008 hist_field->type = "unsigned int"; 2009 goto out; 2010 } 2011 2012 if (WARN_ON_ONCE(!field)) 2013 goto out; 2014 2015 /* Pointers to strings are just pointers and dangerous to dereference */ 2016 if (is_string_field(field) && 2017 (field->filter_type != FILTER_PTR_STRING)) { 2018 flags |= HIST_FIELD_FL_STRING; 2019 2020 hist_field->size = MAX_FILTER_STR_VAL; 2021 hist_field->type = kstrdup_const(field->type, GFP_KERNEL); 2022 if (!hist_field->type) 2023 goto free; 2024 2025 if (field->filter_type == FILTER_STATIC_STRING) { 2026 hist_field->fn_num = HIST_FIELD_FN_STRING; 2027 hist_field->size = field->size; 2028 } else if (field->filter_type == FILTER_DYN_STRING) { 2029 hist_field->fn_num = HIST_FIELD_FN_DYNSTRING; 2030 } else if (field->filter_type == FILTER_RDYN_STRING) 2031 hist_field->fn_num = HIST_FIELD_FN_RELDYNSTRING; 2032 else 2033 hist_field->fn_num = HIST_FIELD_FN_PSTRING; 2034 } else { 2035 hist_field->size = field->size; 2036 hist_field->is_signed = field->is_signed; 2037 hist_field->type = kstrdup_const(field->type, GFP_KERNEL); 2038 if (!hist_field->type) 2039 goto free; 2040 2041 hist_field->fn_num = select_value_fn(field->size, 2042 field->is_signed); 2043 if (hist_field->fn_num == HIST_FIELD_FN_NOP) { 2044 destroy_hist_field(hist_field, 0); 2045 return NULL; 2046 } 2047 } 2048 out: 2049 hist_field->field = field; 2050 hist_field->flags = flags; 2051 2052 if (var_name) { 2053 hist_field->var.name = kstrdup(var_name, GFP_KERNEL); 2054 if (!hist_field->var.name) 2055 goto free; 2056 } 2057 2058 return hist_field; 2059 free: 2060 destroy_hist_field(hist_field, 0); 2061 return NULL; 2062 } 2063 2064 static void destroy_hist_fields(struct hist_trigger_data *hist_data) 2065 { 2066 unsigned int i; 2067 2068 for (i = 0; i < HIST_FIELDS_MAX; i++) { 2069 if (hist_data->fields[i]) { 2070 destroy_hist_field(hist_data->fields[i], 0); 2071 hist_data->fields[i] = NULL; 2072 } 2073 } 2074 2075 for (i = 0; i < hist_data->n_var_refs; i++) { 2076 WARN_ON(!(hist_data->var_refs[i]->flags & HIST_FIELD_FL_VAR_REF)); 2077 __destroy_hist_field(hist_data->var_refs[i]); 2078 hist_data->var_refs[i] = NULL; 2079 } 2080 } 2081 2082 static int init_var_ref(struct hist_field *ref_field, 2083 struct hist_field *var_field, 2084 char *system, char *event_name) 2085 { 2086 int err = 0; 2087 2088 ref_field->var.idx = var_field->var.idx; 2089 ref_field->var.hist_data = var_field->hist_data; 2090 ref_field->size = var_field->size; 2091 ref_field->is_signed = var_field->is_signed; 2092 ref_field->flags |= var_field->flags & 2093 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS); 2094 2095 if (system) { 2096 ref_field->system = kstrdup(system, GFP_KERNEL); 2097 if (!ref_field->system) 2098 return -ENOMEM; 2099 } 2100 2101 if (event_name) { 2102 ref_field->event_name = kstrdup(event_name, GFP_KERNEL); 2103 if (!ref_field->event_name) { 2104 err = -ENOMEM; 2105 goto free; 2106 } 2107 } 2108 2109 if (var_field->var.name) { 2110 ref_field->name = kstrdup(var_field->var.name, GFP_KERNEL); 2111 if (!ref_field->name) { 2112 err = -ENOMEM; 2113 goto free; 2114 } 2115 } else if (var_field->name) { 2116 ref_field->name = kstrdup(var_field->name, GFP_KERNEL); 2117 if (!ref_field->name) { 2118 err = -ENOMEM; 2119 goto free; 2120 } 2121 } 2122 2123 ref_field->type = kstrdup_const(var_field->type, GFP_KERNEL); 2124 if (!ref_field->type) { 2125 err = -ENOMEM; 2126 goto free; 2127 } 2128 out: 2129 return err; 2130 free: 2131 kfree(ref_field->system); 2132 ref_field->system = NULL; 2133 kfree(ref_field->event_name); 2134 ref_field->event_name = NULL; 2135 kfree(ref_field->name); 2136 ref_field->name = NULL; 2137 2138 goto out; 2139 } 2140 2141 static int find_var_ref_idx(struct hist_trigger_data *hist_data, 2142 struct hist_field *var_field) 2143 { 2144 struct hist_field *ref_field; 2145 int i; 2146 2147 for (i = 0; i < hist_data->n_var_refs; i++) { 2148 ref_field = hist_data->var_refs[i]; 2149 if (ref_field->var.idx == var_field->var.idx && 2150 ref_field->var.hist_data == var_field->hist_data) 2151 return i; 2152 } 2153 2154 return -ENOENT; 2155 } 2156 2157 /** 2158 * create_var_ref - Create a variable reference and attach it to trigger 2159 * @hist_data: The trigger that will be referencing the variable 2160 * @var_field: The VAR field to create a reference to 2161 * @system: The optional system string 2162 * @event_name: The optional event_name string 2163 * 2164 * Given a variable hist_field, create a VAR_REF hist_field that 2165 * represents a reference to it. 2166 * 2167 * This function also adds the reference to the trigger that 2168 * now references the variable. 2169 * 2170 * Return: The VAR_REF field if successful, NULL if not 2171 */ 2172 static struct hist_field *create_var_ref(struct hist_trigger_data *hist_data, 2173 struct hist_field *var_field, 2174 char *system, char *event_name) 2175 { 2176 unsigned long flags = HIST_FIELD_FL_VAR_REF; 2177 struct hist_field *ref_field; 2178 int i; 2179 2180 /* Check if the variable already exists */ 2181 for (i = 0; i < hist_data->n_var_refs; i++) { 2182 ref_field = hist_data->var_refs[i]; 2183 if (ref_field->var.idx == var_field->var.idx && 2184 ref_field->var.hist_data == var_field->hist_data) { 2185 get_hist_field(ref_field); 2186 return ref_field; 2187 } 2188 } 2189 /* Sanity check to avoid out-of-bound write on 'hist_data->var_refs' */ 2190 if (hist_data->n_var_refs >= TRACING_MAP_VARS_MAX) 2191 return NULL; 2192 ref_field = create_hist_field(var_field->hist_data, NULL, flags, NULL); 2193 if (ref_field) { 2194 if (init_var_ref(ref_field, var_field, system, event_name)) { 2195 destroy_hist_field(ref_field, 0); 2196 return NULL; 2197 } 2198 2199 hist_data->var_refs[hist_data->n_var_refs] = ref_field; 2200 ref_field->var_ref_idx = hist_data->n_var_refs++; 2201 } 2202 2203 return ref_field; 2204 } 2205 2206 static bool is_var_ref(char *var_name) 2207 { 2208 if (!var_name || strlen(var_name) < 2 || var_name[0] != '$') 2209 return false; 2210 2211 return true; 2212 } 2213 2214 static char *field_name_from_var(struct hist_trigger_data *hist_data, 2215 char *var_name) 2216 { 2217 char *name, *field; 2218 unsigned int i; 2219 2220 for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) { 2221 name = hist_data->attrs->var_defs.name[i]; 2222 2223 if (strcmp(var_name, name) == 0) { 2224 field = hist_data->attrs->var_defs.expr[i]; 2225 if (contains_operator(field, NULL) || is_var_ref(field)) 2226 continue; 2227 return field; 2228 } 2229 } 2230 2231 return NULL; 2232 } 2233 2234 static char *local_field_var_ref(struct hist_trigger_data *hist_data, 2235 char *system, char *event_name, 2236 char *var_name) 2237 { 2238 struct trace_event_call *call; 2239 2240 if (system && event_name) { 2241 call = hist_data->event_file->event_call; 2242 2243 if (strcmp(system, call->class->system) != 0) 2244 return NULL; 2245 2246 if (strcmp(event_name, trace_event_name(call)) != 0) 2247 return NULL; 2248 } 2249 2250 if (!!system != !!event_name) 2251 return NULL; 2252 2253 if (!is_var_ref(var_name)) 2254 return NULL; 2255 2256 var_name++; 2257 2258 return field_name_from_var(hist_data, var_name); 2259 } 2260 2261 static struct hist_field *parse_var_ref(struct hist_trigger_data *hist_data, 2262 char *system, char *event_name, 2263 char *var_name) 2264 { 2265 struct hist_field *var_field = NULL, *ref_field = NULL; 2266 struct trace_array *tr = hist_data->event_file->tr; 2267 2268 if (!is_var_ref(var_name)) 2269 return NULL; 2270 2271 var_name++; 2272 2273 var_field = find_event_var(hist_data, system, event_name, var_name); 2274 if (var_field) 2275 ref_field = create_var_ref(hist_data, var_field, 2276 system, event_name); 2277 2278 if (!ref_field) 2279 hist_err(tr, HIST_ERR_VAR_NOT_FOUND, errpos(var_name)); 2280 2281 return ref_field; 2282 } 2283 2284 static struct ftrace_event_field * 2285 parse_field(struct hist_trigger_data *hist_data, struct trace_event_file *file, 2286 char *field_str, unsigned long *flags, unsigned long *buckets) 2287 { 2288 struct ftrace_event_field *field = NULL; 2289 char *field_name, *modifier, *str; 2290 struct trace_array *tr = file->tr; 2291 2292 modifier = str = kstrdup(field_str, GFP_KERNEL); 2293 if (!modifier) 2294 return ERR_PTR(-ENOMEM); 2295 2296 field_name = strsep(&modifier, "."); 2297 if (modifier) { 2298 if (strcmp(modifier, "hex") == 0) 2299 *flags |= HIST_FIELD_FL_HEX; 2300 else if (strcmp(modifier, "sym") == 0) 2301 *flags |= HIST_FIELD_FL_SYM; 2302 /* 2303 * 'sym-offset' occurrences in the trigger string are modified 2304 * to 'symXoffset' to simplify arithmetic expression parsing. 2305 */ 2306 else if (strcmp(modifier, "symXoffset") == 0) 2307 *flags |= HIST_FIELD_FL_SYM_OFFSET; 2308 else if ((strcmp(modifier, "execname") == 0) && 2309 (strcmp(field_name, "common_pid") == 0)) 2310 *flags |= HIST_FIELD_FL_EXECNAME; 2311 else if (strcmp(modifier, "syscall") == 0) 2312 *flags |= HIST_FIELD_FL_SYSCALL; 2313 else if (strcmp(modifier, "log2") == 0) 2314 *flags |= HIST_FIELD_FL_LOG2; 2315 else if (strcmp(modifier, "usecs") == 0) 2316 *flags |= HIST_FIELD_FL_TIMESTAMP_USECS; 2317 else if (strncmp(modifier, "bucket", 6) == 0) { 2318 int ret; 2319 2320 modifier += 6; 2321 2322 if (*modifier == 's') 2323 modifier++; 2324 if (*modifier != '=') 2325 goto error; 2326 modifier++; 2327 ret = kstrtoul(modifier, 0, buckets); 2328 if (ret || !(*buckets)) 2329 goto error; 2330 *flags |= HIST_FIELD_FL_BUCKET; 2331 } else if (strncmp(modifier, "percent", 7) == 0) { 2332 if (*flags & (HIST_FIELD_FL_VAR | HIST_FIELD_FL_KEY)) 2333 goto error; 2334 *flags |= HIST_FIELD_FL_PERCENT; 2335 } else if (strncmp(modifier, "graph", 5) == 0) { 2336 if (*flags & (HIST_FIELD_FL_VAR | HIST_FIELD_FL_KEY)) 2337 goto error; 2338 *flags |= HIST_FIELD_FL_GRAPH; 2339 } else { 2340 error: 2341 hist_err(tr, HIST_ERR_BAD_FIELD_MODIFIER, errpos(modifier)); 2342 field = ERR_PTR(-EINVAL); 2343 goto out; 2344 } 2345 } 2346 2347 if (strcmp(field_name, "common_timestamp") == 0) { 2348 *flags |= HIST_FIELD_FL_TIMESTAMP; 2349 hist_data->enable_timestamps = true; 2350 if (*flags & HIST_FIELD_FL_TIMESTAMP_USECS) 2351 hist_data->attrs->ts_in_usecs = true; 2352 } else if (strcmp(field_name, "common_cpu") == 0) 2353 *flags |= HIST_FIELD_FL_CPU; 2354 else if (strcmp(field_name, "hitcount") == 0) 2355 *flags |= HIST_FIELD_FL_HITCOUNT; 2356 else { 2357 field = trace_find_event_field(file->event_call, field_name); 2358 if (!field || !field->size) { 2359 /* 2360 * For backward compatibility, if field_name 2361 * was "cpu", then we treat this the same as 2362 * common_cpu. This also works for "CPU". 2363 */ 2364 if (field && field->filter_type == FILTER_CPU) { 2365 *flags |= HIST_FIELD_FL_CPU; 2366 } else { 2367 hist_err(tr, HIST_ERR_FIELD_NOT_FOUND, 2368 errpos(field_name)); 2369 field = ERR_PTR(-EINVAL); 2370 goto out; 2371 } 2372 } 2373 } 2374 out: 2375 kfree(str); 2376 2377 return field; 2378 } 2379 2380 static struct hist_field *create_alias(struct hist_trigger_data *hist_data, 2381 struct hist_field *var_ref, 2382 char *var_name) 2383 { 2384 struct hist_field *alias = NULL; 2385 unsigned long flags = HIST_FIELD_FL_ALIAS | HIST_FIELD_FL_VAR; 2386 2387 alias = create_hist_field(hist_data, NULL, flags, var_name); 2388 if (!alias) 2389 return NULL; 2390 2391 alias->fn_num = var_ref->fn_num; 2392 alias->operands[0] = var_ref; 2393 2394 if (init_var_ref(alias, var_ref, var_ref->system, var_ref->event_name)) { 2395 destroy_hist_field(alias, 0); 2396 return NULL; 2397 } 2398 2399 alias->var_ref_idx = var_ref->var_ref_idx; 2400 2401 return alias; 2402 } 2403 2404 static struct hist_field *parse_const(struct hist_trigger_data *hist_data, 2405 char *str, char *var_name, 2406 unsigned long *flags) 2407 { 2408 struct trace_array *tr = hist_data->event_file->tr; 2409 struct hist_field *field = NULL; 2410 u64 constant; 2411 2412 if (kstrtoull(str, 0, &constant)) { 2413 hist_err(tr, HIST_ERR_EXPECT_NUMBER, errpos(str)); 2414 return NULL; 2415 } 2416 2417 *flags |= HIST_FIELD_FL_CONST; 2418 field = create_hist_field(hist_data, NULL, *flags, var_name); 2419 if (!field) 2420 return NULL; 2421 2422 field->constant = constant; 2423 2424 return field; 2425 } 2426 2427 static struct hist_field *parse_atom(struct hist_trigger_data *hist_data, 2428 struct trace_event_file *file, char *str, 2429 unsigned long *flags, char *var_name) 2430 { 2431 char *s, *ref_system = NULL, *ref_event = NULL, *ref_var = str; 2432 struct ftrace_event_field *field = NULL; 2433 struct hist_field *hist_field = NULL; 2434 unsigned long buckets = 0; 2435 int ret = 0; 2436 2437 if (isdigit(str[0])) { 2438 hist_field = parse_const(hist_data, str, var_name, flags); 2439 if (!hist_field) { 2440 ret = -EINVAL; 2441 goto out; 2442 } 2443 return hist_field; 2444 } 2445 2446 s = strchr(str, '.'); 2447 if (s) { 2448 s = strchr(++s, '.'); 2449 if (s) { 2450 ref_system = strsep(&str, "."); 2451 if (!str) { 2452 ret = -EINVAL; 2453 goto out; 2454 } 2455 ref_event = strsep(&str, "."); 2456 if (!str) { 2457 ret = -EINVAL; 2458 goto out; 2459 } 2460 ref_var = str; 2461 } 2462 } 2463 2464 s = local_field_var_ref(hist_data, ref_system, ref_event, ref_var); 2465 if (!s) { 2466 hist_field = parse_var_ref(hist_data, ref_system, 2467 ref_event, ref_var); 2468 if (hist_field) { 2469 if (var_name) { 2470 hist_field = create_alias(hist_data, hist_field, var_name); 2471 if (!hist_field) { 2472 ret = -ENOMEM; 2473 goto out; 2474 } 2475 } 2476 return hist_field; 2477 } 2478 } else 2479 str = s; 2480 2481 field = parse_field(hist_data, file, str, flags, &buckets); 2482 if (IS_ERR(field)) { 2483 ret = PTR_ERR(field); 2484 goto out; 2485 } 2486 2487 hist_field = create_hist_field(hist_data, field, *flags, var_name); 2488 if (!hist_field) { 2489 ret = -ENOMEM; 2490 goto out; 2491 } 2492 hist_field->buckets = buckets; 2493 2494 return hist_field; 2495 out: 2496 return ERR_PTR(ret); 2497 } 2498 2499 static struct hist_field *parse_expr(struct hist_trigger_data *hist_data, 2500 struct trace_event_file *file, 2501 char *str, unsigned long flags, 2502 char *var_name, unsigned int *n_subexprs); 2503 2504 static struct hist_field *parse_unary(struct hist_trigger_data *hist_data, 2505 struct trace_event_file *file, 2506 char *str, unsigned long flags, 2507 char *var_name, unsigned int *n_subexprs) 2508 { 2509 struct hist_field *operand1, *expr = NULL; 2510 unsigned long operand_flags; 2511 int ret = 0; 2512 char *s; 2513 2514 /* Unary minus operator, increment n_subexprs */ 2515 ++*n_subexprs; 2516 2517 /* we support only -(xxx) i.e. explicit parens required */ 2518 2519 if (*n_subexprs > 3) { 2520 hist_err(file->tr, HIST_ERR_TOO_MANY_SUBEXPR, errpos(str)); 2521 ret = -EINVAL; 2522 goto free; 2523 } 2524 2525 str++; /* skip leading '-' */ 2526 2527 s = strchr(str, '('); 2528 if (s) 2529 str++; 2530 else { 2531 ret = -EINVAL; 2532 goto free; 2533 } 2534 2535 s = strrchr(str, ')'); 2536 if (s) { 2537 /* unary minus not supported in sub-expressions */ 2538 if (*(s+1) != '\0') { 2539 hist_err(file->tr, HIST_ERR_UNARY_MINUS_SUBEXPR, 2540 errpos(str)); 2541 ret = -EINVAL; 2542 goto free; 2543 } 2544 *s = '\0'; 2545 } 2546 else { 2547 ret = -EINVAL; /* no closing ')' */ 2548 goto free; 2549 } 2550 2551 flags |= HIST_FIELD_FL_EXPR; 2552 expr = create_hist_field(hist_data, NULL, flags, var_name); 2553 if (!expr) { 2554 ret = -ENOMEM; 2555 goto free; 2556 } 2557 2558 operand_flags = 0; 2559 operand1 = parse_expr(hist_data, file, str, operand_flags, NULL, n_subexprs); 2560 if (IS_ERR(operand1)) { 2561 ret = PTR_ERR(operand1); 2562 goto free; 2563 } 2564 if (operand1->flags & HIST_FIELD_FL_STRING) { 2565 /* String type can not be the operand of unary operator. */ 2566 hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(str)); 2567 destroy_hist_field(operand1, 0); 2568 ret = -EINVAL; 2569 goto free; 2570 } 2571 2572 expr->flags |= operand1->flags & 2573 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS); 2574 expr->fn_num = HIST_FIELD_FN_UMINUS; 2575 expr->operands[0] = operand1; 2576 expr->size = operand1->size; 2577 expr->is_signed = operand1->is_signed; 2578 expr->operator = FIELD_OP_UNARY_MINUS; 2579 expr->name = expr_str(expr, 0); 2580 expr->type = kstrdup_const(operand1->type, GFP_KERNEL); 2581 if (!expr->type) { 2582 ret = -ENOMEM; 2583 goto free; 2584 } 2585 2586 return expr; 2587 free: 2588 destroy_hist_field(expr, 0); 2589 return ERR_PTR(ret); 2590 } 2591 2592 /* 2593 * If the operands are var refs, return pointers the 2594 * variable(s) referenced in var1 and var2, else NULL. 2595 */ 2596 static int check_expr_operands(struct trace_array *tr, 2597 struct hist_field *operand1, 2598 struct hist_field *operand2, 2599 struct hist_field **var1, 2600 struct hist_field **var2) 2601 { 2602 unsigned long operand1_flags = operand1->flags; 2603 unsigned long operand2_flags = operand2->flags; 2604 2605 if ((operand1_flags & HIST_FIELD_FL_VAR_REF) || 2606 (operand1_flags & HIST_FIELD_FL_ALIAS)) { 2607 struct hist_field *var; 2608 2609 var = find_var_field(operand1->var.hist_data, operand1->name); 2610 if (!var) 2611 return -EINVAL; 2612 operand1_flags = var->flags; 2613 *var1 = var; 2614 } 2615 2616 if ((operand2_flags & HIST_FIELD_FL_VAR_REF) || 2617 (operand2_flags & HIST_FIELD_FL_ALIAS)) { 2618 struct hist_field *var; 2619 2620 var = find_var_field(operand2->var.hist_data, operand2->name); 2621 if (!var) 2622 return -EINVAL; 2623 operand2_flags = var->flags; 2624 *var2 = var; 2625 } 2626 2627 if ((operand1_flags & HIST_FIELD_FL_TIMESTAMP_USECS) != 2628 (operand2_flags & HIST_FIELD_FL_TIMESTAMP_USECS)) { 2629 hist_err(tr, HIST_ERR_TIMESTAMP_MISMATCH, 0); 2630 return -EINVAL; 2631 } 2632 2633 return 0; 2634 } 2635 2636 static struct hist_field *parse_expr(struct hist_trigger_data *hist_data, 2637 struct trace_event_file *file, 2638 char *str, unsigned long flags, 2639 char *var_name, unsigned int *n_subexprs) 2640 { 2641 struct hist_field *operand1 = NULL, *operand2 = NULL, *expr = NULL; 2642 struct hist_field *var1 = NULL, *var2 = NULL; 2643 unsigned long operand_flags, operand2_flags; 2644 int field_op, ret = -EINVAL; 2645 char *sep, *operand1_str; 2646 enum hist_field_fn op_fn; 2647 bool combine_consts; 2648 2649 if (*n_subexprs > 3) { 2650 hist_err(file->tr, HIST_ERR_TOO_MANY_SUBEXPR, errpos(str)); 2651 return ERR_PTR(-EINVAL); 2652 } 2653 2654 field_op = contains_operator(str, &sep); 2655 2656 if (field_op == FIELD_OP_NONE) 2657 return parse_atom(hist_data, file, str, &flags, var_name); 2658 2659 if (field_op == FIELD_OP_UNARY_MINUS) 2660 return parse_unary(hist_data, file, str, flags, var_name, n_subexprs); 2661 2662 /* Binary operator found, increment n_subexprs */ 2663 ++*n_subexprs; 2664 2665 /* Split the expression string at the root operator */ 2666 if (!sep) 2667 return ERR_PTR(-EINVAL); 2668 2669 *sep = '\0'; 2670 operand1_str = str; 2671 str = sep+1; 2672 2673 /* Binary operator requires both operands */ 2674 if (*operand1_str == '\0' || *str == '\0') 2675 return ERR_PTR(-EINVAL); 2676 2677 operand_flags = 0; 2678 2679 /* LHS of string is an expression e.g. a+b in a+b+c */ 2680 operand1 = parse_expr(hist_data, file, operand1_str, operand_flags, NULL, n_subexprs); 2681 if (IS_ERR(operand1)) 2682 return ERR_CAST(operand1); 2683 2684 if (operand1->flags & HIST_FIELD_FL_STRING) { 2685 hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(operand1_str)); 2686 ret = -EINVAL; 2687 goto free_op1; 2688 } 2689 2690 /* RHS of string is another expression e.g. c in a+b+c */ 2691 operand_flags = 0; 2692 operand2 = parse_expr(hist_data, file, str, operand_flags, NULL, n_subexprs); 2693 if (IS_ERR(operand2)) { 2694 ret = PTR_ERR(operand2); 2695 goto free_op1; 2696 } 2697 if (operand2->flags & HIST_FIELD_FL_STRING) { 2698 hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(str)); 2699 ret = -EINVAL; 2700 goto free_operands; 2701 } 2702 2703 switch (field_op) { 2704 case FIELD_OP_MINUS: 2705 op_fn = HIST_FIELD_FN_MINUS; 2706 break; 2707 case FIELD_OP_PLUS: 2708 op_fn = HIST_FIELD_FN_PLUS; 2709 break; 2710 case FIELD_OP_DIV: 2711 op_fn = HIST_FIELD_FN_DIV; 2712 break; 2713 case FIELD_OP_MULT: 2714 op_fn = HIST_FIELD_FN_MULT; 2715 break; 2716 default: 2717 ret = -EINVAL; 2718 goto free_operands; 2719 } 2720 2721 ret = check_expr_operands(file->tr, operand1, operand2, &var1, &var2); 2722 if (ret) 2723 goto free_operands; 2724 2725 operand_flags = var1 ? var1->flags : operand1->flags; 2726 operand2_flags = var2 ? var2->flags : operand2->flags; 2727 2728 /* 2729 * If both operands are constant, the expression can be 2730 * collapsed to a single constant. 2731 */ 2732 combine_consts = operand_flags & operand2_flags & HIST_FIELD_FL_CONST; 2733 2734 flags |= combine_consts ? HIST_FIELD_FL_CONST : HIST_FIELD_FL_EXPR; 2735 2736 flags |= operand1->flags & 2737 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS); 2738 2739 expr = create_hist_field(hist_data, NULL, flags, var_name); 2740 if (!expr) { 2741 ret = -ENOMEM; 2742 goto free_operands; 2743 } 2744 2745 operand1->read_once = true; 2746 operand2->read_once = true; 2747 2748 /* The operands are now owned and free'd by 'expr' */ 2749 expr->operands[0] = operand1; 2750 expr->operands[1] = operand2; 2751 2752 if (field_op == FIELD_OP_DIV && 2753 operand2_flags & HIST_FIELD_FL_CONST) { 2754 u64 divisor = var2 ? var2->constant : operand2->constant; 2755 2756 if (!divisor) { 2757 hist_err(file->tr, HIST_ERR_DIVISION_BY_ZERO, errpos(str)); 2758 ret = -EDOM; 2759 goto free_expr; 2760 } 2761 2762 /* 2763 * Copy the divisor here so we don't have to look it up 2764 * later if this is a var ref 2765 */ 2766 operand2->constant = divisor; 2767 op_fn = hist_field_get_div_fn(operand2); 2768 } 2769 2770 expr->fn_num = op_fn; 2771 2772 if (combine_consts) { 2773 if (var1) 2774 expr->operands[0] = var1; 2775 if (var2) 2776 expr->operands[1] = var2; 2777 2778 expr->constant = hist_fn_call(expr, NULL, NULL, NULL, NULL); 2779 expr->fn_num = HIST_FIELD_FN_CONST; 2780 2781 expr->operands[0] = NULL; 2782 expr->operands[1] = NULL; 2783 2784 /* 2785 * var refs won't be destroyed immediately 2786 * See: destroy_hist_field() 2787 */ 2788 destroy_hist_field(operand2, 0); 2789 destroy_hist_field(operand1, 0); 2790 2791 expr->name = expr_str(expr, 0); 2792 } else { 2793 /* The operand sizes should be the same, so just pick one */ 2794 expr->size = operand1->size; 2795 expr->is_signed = operand1->is_signed; 2796 2797 expr->operator = field_op; 2798 expr->type = kstrdup_const(operand1->type, GFP_KERNEL); 2799 if (!expr->type) { 2800 ret = -ENOMEM; 2801 goto free_expr; 2802 } 2803 2804 expr->name = expr_str(expr, 0); 2805 } 2806 2807 return expr; 2808 2809 free_operands: 2810 destroy_hist_field(operand2, 0); 2811 free_op1: 2812 destroy_hist_field(operand1, 0); 2813 return ERR_PTR(ret); 2814 2815 free_expr: 2816 destroy_hist_field(expr, 0); 2817 return ERR_PTR(ret); 2818 } 2819 2820 static char *find_trigger_filter(struct hist_trigger_data *hist_data, 2821 struct trace_event_file *file) 2822 { 2823 struct event_trigger_data *test; 2824 2825 lockdep_assert_held(&event_mutex); 2826 2827 list_for_each_entry(test, &file->triggers, list) { 2828 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 2829 if (test->private_data == hist_data) 2830 return test->filter_str; 2831 } 2832 } 2833 2834 return NULL; 2835 } 2836 2837 static struct event_command trigger_hist_cmd; 2838 static int event_hist_trigger_parse(struct event_command *cmd_ops, 2839 struct trace_event_file *file, 2840 char *glob, char *cmd, 2841 char *param_and_filter); 2842 2843 static bool compatible_keys(struct hist_trigger_data *target_hist_data, 2844 struct hist_trigger_data *hist_data, 2845 unsigned int n_keys) 2846 { 2847 struct hist_field *target_hist_field, *hist_field; 2848 unsigned int n, i, j; 2849 2850 if (hist_data->n_fields - hist_data->n_vals != n_keys) 2851 return false; 2852 2853 i = hist_data->n_vals; 2854 j = target_hist_data->n_vals; 2855 2856 for (n = 0; n < n_keys; n++) { 2857 hist_field = hist_data->fields[i + n]; 2858 target_hist_field = target_hist_data->fields[j + n]; 2859 2860 if (strcmp(hist_field->type, target_hist_field->type) != 0) 2861 return false; 2862 if (hist_field->size != target_hist_field->size) 2863 return false; 2864 if (hist_field->is_signed != target_hist_field->is_signed) 2865 return false; 2866 } 2867 2868 return true; 2869 } 2870 2871 static struct hist_trigger_data * 2872 find_compatible_hist(struct hist_trigger_data *target_hist_data, 2873 struct trace_event_file *file) 2874 { 2875 struct hist_trigger_data *hist_data; 2876 struct event_trigger_data *test; 2877 unsigned int n_keys; 2878 2879 lockdep_assert_held(&event_mutex); 2880 2881 n_keys = target_hist_data->n_fields - target_hist_data->n_vals; 2882 2883 list_for_each_entry(test, &file->triggers, list) { 2884 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 2885 hist_data = test->private_data; 2886 2887 if (compatible_keys(target_hist_data, hist_data, n_keys)) 2888 return hist_data; 2889 } 2890 } 2891 2892 return NULL; 2893 } 2894 2895 static struct trace_event_file *event_file(struct trace_array *tr, 2896 char *system, char *event_name) 2897 { 2898 struct trace_event_file *file; 2899 2900 file = __find_event_file(tr, system, event_name); 2901 if (!file) 2902 return ERR_PTR(-EINVAL); 2903 2904 return file; 2905 } 2906 2907 static struct hist_field * 2908 find_synthetic_field_var(struct hist_trigger_data *target_hist_data, 2909 char *system, char *event_name, char *field_name) 2910 { 2911 struct hist_field *event_var; 2912 char *synthetic_name; 2913 2914 synthetic_name = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL); 2915 if (!synthetic_name) 2916 return ERR_PTR(-ENOMEM); 2917 2918 strcpy(synthetic_name, "synthetic_"); 2919 strcat(synthetic_name, field_name); 2920 2921 event_var = find_event_var(target_hist_data, system, event_name, synthetic_name); 2922 2923 kfree(synthetic_name); 2924 2925 return event_var; 2926 } 2927 2928 /** 2929 * create_field_var_hist - Automatically create a histogram and var for a field 2930 * @target_hist_data: The target hist trigger 2931 * @subsys_name: Optional subsystem name 2932 * @event_name: Optional event name 2933 * @field_name: The name of the field (and the resulting variable) 2934 * 2935 * Hist trigger actions fetch data from variables, not directly from 2936 * events. However, for convenience, users are allowed to directly 2937 * specify an event field in an action, which will be automatically 2938 * converted into a variable on their behalf. 2939 * 2940 * If a user specifies a field on an event that isn't the event the 2941 * histogram currently being defined (the target event histogram), the 2942 * only way that can be accomplished is if a new hist trigger is 2943 * created and the field variable defined on that. 2944 * 2945 * This function creates a new histogram compatible with the target 2946 * event (meaning a histogram with the same key as the target 2947 * histogram), and creates a variable for the specified field, but 2948 * with 'synthetic_' prepended to the variable name in order to avoid 2949 * collision with normal field variables. 2950 * 2951 * Return: The variable created for the field. 2952 */ 2953 static struct hist_field * 2954 create_field_var_hist(struct hist_trigger_data *target_hist_data, 2955 char *subsys_name, char *event_name, char *field_name) 2956 { 2957 struct trace_array *tr = target_hist_data->event_file->tr; 2958 struct hist_trigger_data *hist_data; 2959 unsigned int i, n, first = true; 2960 struct field_var_hist *var_hist; 2961 struct trace_event_file *file; 2962 struct hist_field *key_field; 2963 struct hist_field *event_var; 2964 char *saved_filter; 2965 char *cmd; 2966 int ret; 2967 2968 if (target_hist_data->n_field_var_hists >= SYNTH_FIELDS_MAX) { 2969 hist_err(tr, HIST_ERR_TOO_MANY_FIELD_VARS, errpos(field_name)); 2970 return ERR_PTR(-EINVAL); 2971 } 2972 2973 file = event_file(tr, subsys_name, event_name); 2974 2975 if (IS_ERR(file)) { 2976 hist_err(tr, HIST_ERR_EVENT_FILE_NOT_FOUND, errpos(field_name)); 2977 ret = PTR_ERR(file); 2978 return ERR_PTR(ret); 2979 } 2980 2981 /* 2982 * Look for a histogram compatible with target. We'll use the 2983 * found histogram specification to create a new matching 2984 * histogram with our variable on it. target_hist_data is not 2985 * yet a registered histogram so we can't use that. 2986 */ 2987 hist_data = find_compatible_hist(target_hist_data, file); 2988 if (!hist_data) { 2989 hist_err(tr, HIST_ERR_HIST_NOT_FOUND, errpos(field_name)); 2990 return ERR_PTR(-EINVAL); 2991 } 2992 2993 /* See if a synthetic field variable has already been created */ 2994 event_var = find_synthetic_field_var(target_hist_data, subsys_name, 2995 event_name, field_name); 2996 if (!IS_ERR_OR_NULL(event_var)) 2997 return event_var; 2998 2999 var_hist = kzalloc(sizeof(*var_hist), GFP_KERNEL); 3000 if (!var_hist) 3001 return ERR_PTR(-ENOMEM); 3002 3003 cmd = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL); 3004 if (!cmd) { 3005 kfree(var_hist); 3006 return ERR_PTR(-ENOMEM); 3007 } 3008 3009 /* Use the same keys as the compatible histogram */ 3010 strcat(cmd, "keys="); 3011 3012 for_each_hist_key_field(i, hist_data) { 3013 key_field = hist_data->fields[i]; 3014 if (!first) 3015 strcat(cmd, ","); 3016 strcat(cmd, key_field->field->name); 3017 first = false; 3018 } 3019 3020 /* Create the synthetic field variable specification */ 3021 strcat(cmd, ":synthetic_"); 3022 strcat(cmd, field_name); 3023 strcat(cmd, "="); 3024 strcat(cmd, field_name); 3025 3026 /* Use the same filter as the compatible histogram */ 3027 saved_filter = find_trigger_filter(hist_data, file); 3028 if (saved_filter) { 3029 strcat(cmd, " if "); 3030 strcat(cmd, saved_filter); 3031 } 3032 3033 var_hist->cmd = kstrdup(cmd, GFP_KERNEL); 3034 if (!var_hist->cmd) { 3035 kfree(cmd); 3036 kfree(var_hist); 3037 return ERR_PTR(-ENOMEM); 3038 } 3039 3040 /* Save the compatible histogram information */ 3041 var_hist->hist_data = hist_data; 3042 3043 /* Create the new histogram with our variable */ 3044 ret = event_hist_trigger_parse(&trigger_hist_cmd, file, 3045 "", "hist", cmd); 3046 if (ret) { 3047 kfree(cmd); 3048 kfree(var_hist->cmd); 3049 kfree(var_hist); 3050 hist_err(tr, HIST_ERR_HIST_CREATE_FAIL, errpos(field_name)); 3051 return ERR_PTR(ret); 3052 } 3053 3054 kfree(cmd); 3055 3056 /* If we can't find the variable, something went wrong */ 3057 event_var = find_synthetic_field_var(target_hist_data, subsys_name, 3058 event_name, field_name); 3059 if (IS_ERR_OR_NULL(event_var)) { 3060 kfree(var_hist->cmd); 3061 kfree(var_hist); 3062 hist_err(tr, HIST_ERR_SYNTH_VAR_NOT_FOUND, errpos(field_name)); 3063 return ERR_PTR(-EINVAL); 3064 } 3065 3066 n = target_hist_data->n_field_var_hists; 3067 target_hist_data->field_var_hists[n] = var_hist; 3068 target_hist_data->n_field_var_hists++; 3069 3070 return event_var; 3071 } 3072 3073 static struct hist_field * 3074 find_target_event_var(struct hist_trigger_data *hist_data, 3075 char *subsys_name, char *event_name, char *var_name) 3076 { 3077 struct trace_event_file *file = hist_data->event_file; 3078 struct hist_field *hist_field = NULL; 3079 3080 if (subsys_name) { 3081 struct trace_event_call *call; 3082 3083 if (!event_name) 3084 return NULL; 3085 3086 call = file->event_call; 3087 3088 if (strcmp(subsys_name, call->class->system) != 0) 3089 return NULL; 3090 3091 if (strcmp(event_name, trace_event_name(call)) != 0) 3092 return NULL; 3093 } 3094 3095 hist_field = find_var_field(hist_data, var_name); 3096 3097 return hist_field; 3098 } 3099 3100 static inline void __update_field_vars(struct tracing_map_elt *elt, 3101 struct trace_buffer *buffer, 3102 struct ring_buffer_event *rbe, 3103 void *rec, 3104 struct field_var **field_vars, 3105 unsigned int n_field_vars, 3106 unsigned int field_var_str_start) 3107 { 3108 struct hist_elt_data *elt_data = elt->private_data; 3109 unsigned int i, j, var_idx; 3110 u64 var_val; 3111 3112 for (i = 0, j = field_var_str_start; i < n_field_vars; i++) { 3113 struct field_var *field_var = field_vars[i]; 3114 struct hist_field *var = field_var->var; 3115 struct hist_field *val = field_var->val; 3116 3117 var_val = hist_fn_call(val, elt, buffer, rbe, rec); 3118 var_idx = var->var.idx; 3119 3120 if (val->flags & HIST_FIELD_FL_STRING) { 3121 char *str = elt_data->field_var_str[j++]; 3122 char *val_str = (char *)(uintptr_t)var_val; 3123 unsigned int size; 3124 3125 size = min(val->size, STR_VAR_LEN_MAX); 3126 strscpy(str, val_str, size); 3127 var_val = (u64)(uintptr_t)str; 3128 } 3129 tracing_map_set_var(elt, var_idx, var_val); 3130 } 3131 } 3132 3133 static void update_field_vars(struct hist_trigger_data *hist_data, 3134 struct tracing_map_elt *elt, 3135 struct trace_buffer *buffer, 3136 struct ring_buffer_event *rbe, 3137 void *rec) 3138 { 3139 __update_field_vars(elt, buffer, rbe, rec, hist_data->field_vars, 3140 hist_data->n_field_vars, 0); 3141 } 3142 3143 static void save_track_data_vars(struct hist_trigger_data *hist_data, 3144 struct tracing_map_elt *elt, 3145 struct trace_buffer *buffer, void *rec, 3146 struct ring_buffer_event *rbe, void *key, 3147 struct action_data *data, u64 *var_ref_vals) 3148 { 3149 __update_field_vars(elt, buffer, rbe, rec, hist_data->save_vars, 3150 hist_data->n_save_vars, hist_data->n_field_var_str); 3151 } 3152 3153 static struct hist_field *create_var(struct hist_trigger_data *hist_data, 3154 struct trace_event_file *file, 3155 char *name, int size, const char *type) 3156 { 3157 struct hist_field *var; 3158 int idx; 3159 3160 if (find_var(hist_data, file, name) && !hist_data->remove) { 3161 var = ERR_PTR(-EINVAL); 3162 goto out; 3163 } 3164 3165 var = kzalloc(sizeof(struct hist_field), GFP_KERNEL); 3166 if (!var) { 3167 var = ERR_PTR(-ENOMEM); 3168 goto out; 3169 } 3170 3171 idx = tracing_map_add_var(hist_data->map); 3172 if (idx < 0) { 3173 kfree(var); 3174 var = ERR_PTR(-EINVAL); 3175 goto out; 3176 } 3177 3178 var->ref = 1; 3179 var->flags = HIST_FIELD_FL_VAR; 3180 var->var.idx = idx; 3181 var->var.hist_data = var->hist_data = hist_data; 3182 var->size = size; 3183 var->var.name = kstrdup(name, GFP_KERNEL); 3184 var->type = kstrdup_const(type, GFP_KERNEL); 3185 if (!var->var.name || !var->type) { 3186 kfree_const(var->type); 3187 kfree(var->var.name); 3188 kfree(var); 3189 var = ERR_PTR(-ENOMEM); 3190 } 3191 out: 3192 return var; 3193 } 3194 3195 static struct field_var *create_field_var(struct hist_trigger_data *hist_data, 3196 struct trace_event_file *file, 3197 char *field_name) 3198 { 3199 struct hist_field *val = NULL, *var = NULL; 3200 unsigned long flags = HIST_FIELD_FL_VAR; 3201 struct trace_array *tr = file->tr; 3202 struct field_var *field_var; 3203 int ret = 0; 3204 3205 if (hist_data->n_field_vars >= SYNTH_FIELDS_MAX) { 3206 hist_err(tr, HIST_ERR_TOO_MANY_FIELD_VARS, errpos(field_name)); 3207 ret = -EINVAL; 3208 goto err; 3209 } 3210 3211 val = parse_atom(hist_data, file, field_name, &flags, NULL); 3212 if (IS_ERR(val)) { 3213 hist_err(tr, HIST_ERR_FIELD_VAR_PARSE_FAIL, errpos(field_name)); 3214 ret = PTR_ERR(val); 3215 goto err; 3216 } 3217 3218 var = create_var(hist_data, file, field_name, val->size, val->type); 3219 if (IS_ERR(var)) { 3220 hist_err(tr, HIST_ERR_VAR_CREATE_FIND_FAIL, errpos(field_name)); 3221 kfree(val); 3222 ret = PTR_ERR(var); 3223 goto err; 3224 } 3225 3226 field_var = kzalloc(sizeof(struct field_var), GFP_KERNEL); 3227 if (!field_var) { 3228 kfree(val); 3229 kfree(var); 3230 ret = -ENOMEM; 3231 goto err; 3232 } 3233 3234 field_var->var = var; 3235 field_var->val = val; 3236 out: 3237 return field_var; 3238 err: 3239 field_var = ERR_PTR(ret); 3240 goto out; 3241 } 3242 3243 /** 3244 * create_target_field_var - Automatically create a variable for a field 3245 * @target_hist_data: The target hist trigger 3246 * @subsys_name: Optional subsystem name 3247 * @event_name: Optional event name 3248 * @var_name: The name of the field (and the resulting variable) 3249 * 3250 * Hist trigger actions fetch data from variables, not directly from 3251 * events. However, for convenience, users are allowed to directly 3252 * specify an event field in an action, which will be automatically 3253 * converted into a variable on their behalf. 3254 * 3255 * This function creates a field variable with the name var_name on 3256 * the hist trigger currently being defined on the target event. If 3257 * subsys_name and event_name are specified, this function simply 3258 * verifies that they do in fact match the target event subsystem and 3259 * event name. 3260 * 3261 * Return: The variable created for the field. 3262 */ 3263 static struct field_var * 3264 create_target_field_var(struct hist_trigger_data *target_hist_data, 3265 char *subsys_name, char *event_name, char *var_name) 3266 { 3267 struct trace_event_file *file = target_hist_data->event_file; 3268 3269 if (subsys_name) { 3270 struct trace_event_call *call; 3271 3272 if (!event_name) 3273 return NULL; 3274 3275 call = file->event_call; 3276 3277 if (strcmp(subsys_name, call->class->system) != 0) 3278 return NULL; 3279 3280 if (strcmp(event_name, trace_event_name(call)) != 0) 3281 return NULL; 3282 } 3283 3284 return create_field_var(target_hist_data, file, var_name); 3285 } 3286 3287 static bool check_track_val_max(u64 track_val, u64 var_val) 3288 { 3289 if (var_val <= track_val) 3290 return false; 3291 3292 return true; 3293 } 3294 3295 static bool check_track_val_changed(u64 track_val, u64 var_val) 3296 { 3297 if (var_val == track_val) 3298 return false; 3299 3300 return true; 3301 } 3302 3303 static u64 get_track_val(struct hist_trigger_data *hist_data, 3304 struct tracing_map_elt *elt, 3305 struct action_data *data) 3306 { 3307 unsigned int track_var_idx = data->track_data.track_var->var.idx; 3308 u64 track_val; 3309 3310 track_val = tracing_map_read_var(elt, track_var_idx); 3311 3312 return track_val; 3313 } 3314 3315 static void save_track_val(struct hist_trigger_data *hist_data, 3316 struct tracing_map_elt *elt, 3317 struct action_data *data, u64 var_val) 3318 { 3319 unsigned int track_var_idx = data->track_data.track_var->var.idx; 3320 3321 tracing_map_set_var(elt, track_var_idx, var_val); 3322 } 3323 3324 static void save_track_data(struct hist_trigger_data *hist_data, 3325 struct tracing_map_elt *elt, 3326 struct trace_buffer *buffer, void *rec, 3327 struct ring_buffer_event *rbe, void *key, 3328 struct action_data *data, u64 *var_ref_vals) 3329 { 3330 if (data->track_data.save_data) 3331 data->track_data.save_data(hist_data, elt, buffer, rec, rbe, 3332 key, data, var_ref_vals); 3333 } 3334 3335 static bool check_track_val(struct tracing_map_elt *elt, 3336 struct action_data *data, 3337 u64 var_val) 3338 { 3339 struct hist_trigger_data *hist_data; 3340 u64 track_val; 3341 3342 hist_data = data->track_data.track_var->hist_data; 3343 track_val = get_track_val(hist_data, elt, data); 3344 3345 return data->track_data.check_val(track_val, var_val); 3346 } 3347 3348 #ifdef CONFIG_TRACER_SNAPSHOT 3349 static bool cond_snapshot_update(struct trace_array *tr, void *cond_data) 3350 { 3351 /* called with tr->max_lock held */ 3352 struct track_data *track_data = tr->cond_snapshot->cond_data; 3353 struct hist_elt_data *elt_data, *track_elt_data; 3354 struct snapshot_context *context = cond_data; 3355 struct action_data *action; 3356 u64 track_val; 3357 3358 if (!track_data) 3359 return false; 3360 3361 action = track_data->action_data; 3362 3363 track_val = get_track_val(track_data->hist_data, context->elt, 3364 track_data->action_data); 3365 3366 if (!action->track_data.check_val(track_data->track_val, track_val)) 3367 return false; 3368 3369 track_data->track_val = track_val; 3370 memcpy(track_data->key, context->key, track_data->key_len); 3371 3372 elt_data = context->elt->private_data; 3373 track_elt_data = track_data->elt.private_data; 3374 if (elt_data->comm) 3375 strncpy(track_elt_data->comm, elt_data->comm, TASK_COMM_LEN); 3376 3377 track_data->updated = true; 3378 3379 return true; 3380 } 3381 3382 static void save_track_data_snapshot(struct hist_trigger_data *hist_data, 3383 struct tracing_map_elt *elt, 3384 struct trace_buffer *buffer, void *rec, 3385 struct ring_buffer_event *rbe, void *key, 3386 struct action_data *data, 3387 u64 *var_ref_vals) 3388 { 3389 struct trace_event_file *file = hist_data->event_file; 3390 struct snapshot_context context; 3391 3392 context.elt = elt; 3393 context.key = key; 3394 3395 tracing_snapshot_cond(file->tr, &context); 3396 } 3397 3398 static void hist_trigger_print_key(struct seq_file *m, 3399 struct hist_trigger_data *hist_data, 3400 void *key, 3401 struct tracing_map_elt *elt); 3402 3403 static struct action_data *snapshot_action(struct hist_trigger_data *hist_data) 3404 { 3405 unsigned int i; 3406 3407 if (!hist_data->n_actions) 3408 return NULL; 3409 3410 for (i = 0; i < hist_data->n_actions; i++) { 3411 struct action_data *data = hist_data->actions[i]; 3412 3413 if (data->action == ACTION_SNAPSHOT) 3414 return data; 3415 } 3416 3417 return NULL; 3418 } 3419 3420 static void track_data_snapshot_print(struct seq_file *m, 3421 struct hist_trigger_data *hist_data) 3422 { 3423 struct trace_event_file *file = hist_data->event_file; 3424 struct track_data *track_data; 3425 struct action_data *action; 3426 3427 track_data = tracing_cond_snapshot_data(file->tr); 3428 if (!track_data) 3429 return; 3430 3431 if (!track_data->updated) 3432 return; 3433 3434 action = snapshot_action(hist_data); 3435 if (!action) 3436 return; 3437 3438 seq_puts(m, "\nSnapshot taken (see tracing/snapshot). Details:\n"); 3439 seq_printf(m, "\ttriggering value { %s(%s) }: %10llu", 3440 action->handler == HANDLER_ONMAX ? "onmax" : "onchange", 3441 action->track_data.var_str, track_data->track_val); 3442 3443 seq_puts(m, "\ttriggered by event with key: "); 3444 hist_trigger_print_key(m, hist_data, track_data->key, &track_data->elt); 3445 seq_putc(m, '\n'); 3446 } 3447 #else 3448 static bool cond_snapshot_update(struct trace_array *tr, void *cond_data) 3449 { 3450 return false; 3451 } 3452 static void save_track_data_snapshot(struct hist_trigger_data *hist_data, 3453 struct tracing_map_elt *elt, 3454 struct trace_buffer *buffer, void *rec, 3455 struct ring_buffer_event *rbe, void *key, 3456 struct action_data *data, 3457 u64 *var_ref_vals) {} 3458 static void track_data_snapshot_print(struct seq_file *m, 3459 struct hist_trigger_data *hist_data) {} 3460 #endif /* CONFIG_TRACER_SNAPSHOT */ 3461 3462 static void track_data_print(struct seq_file *m, 3463 struct hist_trigger_data *hist_data, 3464 struct tracing_map_elt *elt, 3465 struct action_data *data) 3466 { 3467 u64 track_val = get_track_val(hist_data, elt, data); 3468 unsigned int i, save_var_idx; 3469 3470 if (data->handler == HANDLER_ONMAX) 3471 seq_printf(m, "\n\tmax: %10llu", track_val); 3472 else if (data->handler == HANDLER_ONCHANGE) 3473 seq_printf(m, "\n\tchanged: %10llu", track_val); 3474 3475 if (data->action == ACTION_SNAPSHOT) 3476 return; 3477 3478 for (i = 0; i < hist_data->n_save_vars; i++) { 3479 struct hist_field *save_val = hist_data->save_vars[i]->val; 3480 struct hist_field *save_var = hist_data->save_vars[i]->var; 3481 u64 val; 3482 3483 save_var_idx = save_var->var.idx; 3484 3485 val = tracing_map_read_var(elt, save_var_idx); 3486 3487 if (save_val->flags & HIST_FIELD_FL_STRING) { 3488 seq_printf(m, " %s: %-32s", save_var->var.name, 3489 (char *)(uintptr_t)(val)); 3490 } else 3491 seq_printf(m, " %s: %10llu", save_var->var.name, val); 3492 } 3493 } 3494 3495 static void ontrack_action(struct hist_trigger_data *hist_data, 3496 struct tracing_map_elt *elt, 3497 struct trace_buffer *buffer, void *rec, 3498 struct ring_buffer_event *rbe, void *key, 3499 struct action_data *data, u64 *var_ref_vals) 3500 { 3501 u64 var_val = var_ref_vals[data->track_data.var_ref->var_ref_idx]; 3502 3503 if (check_track_val(elt, data, var_val)) { 3504 save_track_val(hist_data, elt, data, var_val); 3505 save_track_data(hist_data, elt, buffer, rec, rbe, 3506 key, data, var_ref_vals); 3507 } 3508 } 3509 3510 static void action_data_destroy(struct action_data *data) 3511 { 3512 unsigned int i; 3513 3514 lockdep_assert_held(&event_mutex); 3515 3516 kfree(data->action_name); 3517 3518 for (i = 0; i < data->n_params; i++) 3519 kfree(data->params[i]); 3520 3521 if (data->synth_event) 3522 data->synth_event->ref--; 3523 3524 kfree(data->synth_event_name); 3525 3526 kfree(data); 3527 } 3528 3529 static void track_data_destroy(struct hist_trigger_data *hist_data, 3530 struct action_data *data) 3531 { 3532 struct trace_event_file *file = hist_data->event_file; 3533 3534 destroy_hist_field(data->track_data.track_var, 0); 3535 3536 if (data->action == ACTION_SNAPSHOT) { 3537 struct track_data *track_data; 3538 3539 track_data = tracing_cond_snapshot_data(file->tr); 3540 if (track_data && track_data->hist_data == hist_data) { 3541 tracing_snapshot_cond_disable(file->tr); 3542 track_data_free(track_data); 3543 } 3544 } 3545 3546 kfree(data->track_data.var_str); 3547 3548 action_data_destroy(data); 3549 } 3550 3551 static int action_create(struct hist_trigger_data *hist_data, 3552 struct action_data *data); 3553 3554 static int track_data_create(struct hist_trigger_data *hist_data, 3555 struct action_data *data) 3556 { 3557 struct hist_field *var_field, *ref_field, *track_var = NULL; 3558 struct trace_event_file *file = hist_data->event_file; 3559 struct trace_array *tr = file->tr; 3560 char *track_data_var_str; 3561 int ret = 0; 3562 3563 track_data_var_str = data->track_data.var_str; 3564 if (track_data_var_str[0] != '$') { 3565 hist_err(tr, HIST_ERR_ONX_NOT_VAR, errpos(track_data_var_str)); 3566 return -EINVAL; 3567 } 3568 track_data_var_str++; 3569 3570 var_field = find_target_event_var(hist_data, NULL, NULL, track_data_var_str); 3571 if (!var_field) { 3572 hist_err(tr, HIST_ERR_ONX_VAR_NOT_FOUND, errpos(track_data_var_str)); 3573 return -EINVAL; 3574 } 3575 3576 ref_field = create_var_ref(hist_data, var_field, NULL, NULL); 3577 if (!ref_field) 3578 return -ENOMEM; 3579 3580 data->track_data.var_ref = ref_field; 3581 3582 if (data->handler == HANDLER_ONMAX) 3583 track_var = create_var(hist_data, file, "__max", sizeof(u64), "u64"); 3584 if (IS_ERR(track_var)) { 3585 hist_err(tr, HIST_ERR_ONX_VAR_CREATE_FAIL, 0); 3586 ret = PTR_ERR(track_var); 3587 goto out; 3588 } 3589 3590 if (data->handler == HANDLER_ONCHANGE) 3591 track_var = create_var(hist_data, file, "__change", sizeof(u64), "u64"); 3592 if (IS_ERR(track_var)) { 3593 hist_err(tr, HIST_ERR_ONX_VAR_CREATE_FAIL, 0); 3594 ret = PTR_ERR(track_var); 3595 goto out; 3596 } 3597 data->track_data.track_var = track_var; 3598 3599 ret = action_create(hist_data, data); 3600 out: 3601 return ret; 3602 } 3603 3604 static int parse_action_params(struct trace_array *tr, char *params, 3605 struct action_data *data) 3606 { 3607 char *param, *saved_param; 3608 bool first_param = true; 3609 int ret = 0; 3610 3611 while (params) { 3612 if (data->n_params >= SYNTH_FIELDS_MAX) { 3613 hist_err(tr, HIST_ERR_TOO_MANY_PARAMS, 0); 3614 ret = -EINVAL; 3615 goto out; 3616 } 3617 3618 param = strsep(¶ms, ","); 3619 if (!param) { 3620 hist_err(tr, HIST_ERR_PARAM_NOT_FOUND, 0); 3621 ret = -EINVAL; 3622 goto out; 3623 } 3624 3625 param = strstrip(param); 3626 if (strlen(param) < 2) { 3627 hist_err(tr, HIST_ERR_INVALID_PARAM, errpos(param)); 3628 ret = -EINVAL; 3629 goto out; 3630 } 3631 3632 saved_param = kstrdup(param, GFP_KERNEL); 3633 if (!saved_param) { 3634 ret = -ENOMEM; 3635 goto out; 3636 } 3637 3638 if (first_param && data->use_trace_keyword) { 3639 data->synth_event_name = saved_param; 3640 first_param = false; 3641 continue; 3642 } 3643 first_param = false; 3644 3645 data->params[data->n_params++] = saved_param; 3646 } 3647 out: 3648 return ret; 3649 } 3650 3651 static int action_parse(struct trace_array *tr, char *str, struct action_data *data, 3652 enum handler_id handler) 3653 { 3654 char *action_name; 3655 int ret = 0; 3656 3657 strsep(&str, "."); 3658 if (!str) { 3659 hist_err(tr, HIST_ERR_ACTION_NOT_FOUND, 0); 3660 ret = -EINVAL; 3661 goto out; 3662 } 3663 3664 action_name = strsep(&str, "("); 3665 if (!action_name || !str) { 3666 hist_err(tr, HIST_ERR_ACTION_NOT_FOUND, 0); 3667 ret = -EINVAL; 3668 goto out; 3669 } 3670 3671 if (str_has_prefix(action_name, "save")) { 3672 char *params = strsep(&str, ")"); 3673 3674 if (!params) { 3675 hist_err(tr, HIST_ERR_NO_SAVE_PARAMS, 0); 3676 ret = -EINVAL; 3677 goto out; 3678 } 3679 3680 ret = parse_action_params(tr, params, data); 3681 if (ret) 3682 goto out; 3683 3684 if (handler == HANDLER_ONMAX) 3685 data->track_data.check_val = check_track_val_max; 3686 else if (handler == HANDLER_ONCHANGE) 3687 data->track_data.check_val = check_track_val_changed; 3688 else { 3689 hist_err(tr, HIST_ERR_ACTION_MISMATCH, errpos(action_name)); 3690 ret = -EINVAL; 3691 goto out; 3692 } 3693 3694 data->track_data.save_data = save_track_data_vars; 3695 data->fn = ontrack_action; 3696 data->action = ACTION_SAVE; 3697 } else if (str_has_prefix(action_name, "snapshot")) { 3698 char *params = strsep(&str, ")"); 3699 3700 if (!str) { 3701 hist_err(tr, HIST_ERR_NO_CLOSING_PAREN, errpos(params)); 3702 ret = -EINVAL; 3703 goto out; 3704 } 3705 3706 if (handler == HANDLER_ONMAX) 3707 data->track_data.check_val = check_track_val_max; 3708 else if (handler == HANDLER_ONCHANGE) 3709 data->track_data.check_val = check_track_val_changed; 3710 else { 3711 hist_err(tr, HIST_ERR_ACTION_MISMATCH, errpos(action_name)); 3712 ret = -EINVAL; 3713 goto out; 3714 } 3715 3716 data->track_data.save_data = save_track_data_snapshot; 3717 data->fn = ontrack_action; 3718 data->action = ACTION_SNAPSHOT; 3719 } else { 3720 char *params = strsep(&str, ")"); 3721 3722 if (str_has_prefix(action_name, "trace")) 3723 data->use_trace_keyword = true; 3724 3725 if (params) { 3726 ret = parse_action_params(tr, params, data); 3727 if (ret) 3728 goto out; 3729 } 3730 3731 if (handler == HANDLER_ONMAX) 3732 data->track_data.check_val = check_track_val_max; 3733 else if (handler == HANDLER_ONCHANGE) 3734 data->track_data.check_val = check_track_val_changed; 3735 3736 if (handler != HANDLER_ONMATCH) { 3737 data->track_data.save_data = action_trace; 3738 data->fn = ontrack_action; 3739 } else 3740 data->fn = action_trace; 3741 3742 data->action = ACTION_TRACE; 3743 } 3744 3745 data->action_name = kstrdup(action_name, GFP_KERNEL); 3746 if (!data->action_name) { 3747 ret = -ENOMEM; 3748 goto out; 3749 } 3750 3751 data->handler = handler; 3752 out: 3753 return ret; 3754 } 3755 3756 static struct action_data *track_data_parse(struct hist_trigger_data *hist_data, 3757 char *str, enum handler_id handler) 3758 { 3759 struct action_data *data; 3760 int ret = -EINVAL; 3761 char *var_str; 3762 3763 data = kzalloc(sizeof(*data), GFP_KERNEL); 3764 if (!data) 3765 return ERR_PTR(-ENOMEM); 3766 3767 var_str = strsep(&str, ")"); 3768 if (!var_str || !str) { 3769 ret = -EINVAL; 3770 goto free; 3771 } 3772 3773 data->track_data.var_str = kstrdup(var_str, GFP_KERNEL); 3774 if (!data->track_data.var_str) { 3775 ret = -ENOMEM; 3776 goto free; 3777 } 3778 3779 ret = action_parse(hist_data->event_file->tr, str, data, handler); 3780 if (ret) 3781 goto free; 3782 out: 3783 return data; 3784 free: 3785 track_data_destroy(hist_data, data); 3786 data = ERR_PTR(ret); 3787 goto out; 3788 } 3789 3790 static void onmatch_destroy(struct action_data *data) 3791 { 3792 kfree(data->match_data.event); 3793 kfree(data->match_data.event_system); 3794 3795 action_data_destroy(data); 3796 } 3797 3798 static void destroy_field_var(struct field_var *field_var) 3799 { 3800 if (!field_var) 3801 return; 3802 3803 destroy_hist_field(field_var->var, 0); 3804 destroy_hist_field(field_var->val, 0); 3805 3806 kfree(field_var); 3807 } 3808 3809 static void destroy_field_vars(struct hist_trigger_data *hist_data) 3810 { 3811 unsigned int i; 3812 3813 for (i = 0; i < hist_data->n_field_vars; i++) 3814 destroy_field_var(hist_data->field_vars[i]); 3815 3816 for (i = 0; i < hist_data->n_save_vars; i++) 3817 destroy_field_var(hist_data->save_vars[i]); 3818 } 3819 3820 static void save_field_var(struct hist_trigger_data *hist_data, 3821 struct field_var *field_var) 3822 { 3823 hist_data->field_vars[hist_data->n_field_vars++] = field_var; 3824 3825 if (field_var->val->flags & HIST_FIELD_FL_STRING) 3826 hist_data->n_field_var_str++; 3827 } 3828 3829 3830 static int check_synth_field(struct synth_event *event, 3831 struct hist_field *hist_field, 3832 unsigned int field_pos) 3833 { 3834 struct synth_field *field; 3835 3836 if (field_pos >= event->n_fields) 3837 return -EINVAL; 3838 3839 field = event->fields[field_pos]; 3840 3841 /* 3842 * A dynamic string synth field can accept static or 3843 * dynamic. A static string synth field can only accept a 3844 * same-sized static string, which is checked for later. 3845 */ 3846 if (strstr(hist_field->type, "char[") && field->is_string 3847 && field->is_dynamic) 3848 return 0; 3849 3850 if (strcmp(field->type, hist_field->type) != 0) { 3851 if (field->size != hist_field->size || 3852 (!field->is_string && field->is_signed != hist_field->is_signed)) 3853 return -EINVAL; 3854 } 3855 3856 return 0; 3857 } 3858 3859 static struct hist_field * 3860 trace_action_find_var(struct hist_trigger_data *hist_data, 3861 struct action_data *data, 3862 char *system, char *event, char *var) 3863 { 3864 struct trace_array *tr = hist_data->event_file->tr; 3865 struct hist_field *hist_field; 3866 3867 var++; /* skip '$' */ 3868 3869 hist_field = find_target_event_var(hist_data, system, event, var); 3870 if (!hist_field) { 3871 if (!system && data->handler == HANDLER_ONMATCH) { 3872 system = data->match_data.event_system; 3873 event = data->match_data.event; 3874 } 3875 3876 hist_field = find_event_var(hist_data, system, event, var); 3877 } 3878 3879 if (!hist_field) 3880 hist_err(tr, HIST_ERR_PARAM_NOT_FOUND, errpos(var)); 3881 3882 return hist_field; 3883 } 3884 3885 static struct hist_field * 3886 trace_action_create_field_var(struct hist_trigger_data *hist_data, 3887 struct action_data *data, char *system, 3888 char *event, char *var) 3889 { 3890 struct hist_field *hist_field = NULL; 3891 struct field_var *field_var; 3892 3893 /* 3894 * First try to create a field var on the target event (the 3895 * currently being defined). This will create a variable for 3896 * unqualified fields on the target event, or if qualified, 3897 * target fields that have qualified names matching the target. 3898 */ 3899 field_var = create_target_field_var(hist_data, system, event, var); 3900 3901 if (field_var && !IS_ERR(field_var)) { 3902 save_field_var(hist_data, field_var); 3903 hist_field = field_var->var; 3904 } else { 3905 field_var = NULL; 3906 /* 3907 * If no explicit system.event is specified, default to 3908 * looking for fields on the onmatch(system.event.xxx) 3909 * event. 3910 */ 3911 if (!system && data->handler == HANDLER_ONMATCH) { 3912 system = data->match_data.event_system; 3913 event = data->match_data.event; 3914 } 3915 3916 if (!event) 3917 goto free; 3918 /* 3919 * At this point, we're looking at a field on another 3920 * event. Because we can't modify a hist trigger on 3921 * another event to add a variable for a field, we need 3922 * to create a new trigger on that event and create the 3923 * variable at the same time. 3924 */ 3925 hist_field = create_field_var_hist(hist_data, system, event, var); 3926 if (IS_ERR(hist_field)) 3927 goto free; 3928 } 3929 out: 3930 return hist_field; 3931 free: 3932 destroy_field_var(field_var); 3933 hist_field = NULL; 3934 goto out; 3935 } 3936 3937 static int trace_action_create(struct hist_trigger_data *hist_data, 3938 struct action_data *data) 3939 { 3940 struct trace_array *tr = hist_data->event_file->tr; 3941 char *event_name, *param, *system = NULL; 3942 struct hist_field *hist_field, *var_ref; 3943 unsigned int i; 3944 unsigned int field_pos = 0; 3945 struct synth_event *event; 3946 char *synth_event_name; 3947 int var_ref_idx, ret = 0; 3948 3949 lockdep_assert_held(&event_mutex); 3950 3951 /* Sanity check to avoid out-of-bound write on 'data->var_ref_idx' */ 3952 if (data->n_params > SYNTH_FIELDS_MAX) 3953 return -EINVAL; 3954 3955 if (data->use_trace_keyword) 3956 synth_event_name = data->synth_event_name; 3957 else 3958 synth_event_name = data->action_name; 3959 3960 event = find_synth_event(synth_event_name); 3961 if (!event) { 3962 hist_err(tr, HIST_ERR_SYNTH_EVENT_NOT_FOUND, errpos(synth_event_name)); 3963 return -EINVAL; 3964 } 3965 3966 event->ref++; 3967 3968 for (i = 0; i < data->n_params; i++) { 3969 char *p; 3970 3971 p = param = kstrdup(data->params[i], GFP_KERNEL); 3972 if (!param) { 3973 ret = -ENOMEM; 3974 goto err; 3975 } 3976 3977 system = strsep(¶m, "."); 3978 if (!param) { 3979 param = (char *)system; 3980 system = event_name = NULL; 3981 } else { 3982 event_name = strsep(¶m, "."); 3983 if (!param) { 3984 kfree(p); 3985 ret = -EINVAL; 3986 goto err; 3987 } 3988 } 3989 3990 if (param[0] == '$') 3991 hist_field = trace_action_find_var(hist_data, data, 3992 system, event_name, 3993 param); 3994 else 3995 hist_field = trace_action_create_field_var(hist_data, 3996 data, 3997 system, 3998 event_name, 3999 param); 4000 4001 if (!hist_field) { 4002 kfree(p); 4003 ret = -EINVAL; 4004 goto err; 4005 } 4006 4007 if (check_synth_field(event, hist_field, field_pos) == 0) { 4008 var_ref = create_var_ref(hist_data, hist_field, 4009 system, event_name); 4010 if (!var_ref) { 4011 kfree(p); 4012 ret = -ENOMEM; 4013 goto err; 4014 } 4015 4016 var_ref_idx = find_var_ref_idx(hist_data, var_ref); 4017 if (WARN_ON(var_ref_idx < 0)) { 4018 kfree(p); 4019 ret = var_ref_idx; 4020 goto err; 4021 } 4022 4023 data->var_ref_idx[i] = var_ref_idx; 4024 4025 field_pos++; 4026 kfree(p); 4027 continue; 4028 } 4029 4030 hist_err(tr, HIST_ERR_SYNTH_TYPE_MISMATCH, errpos(param)); 4031 kfree(p); 4032 ret = -EINVAL; 4033 goto err; 4034 } 4035 4036 if (field_pos != event->n_fields) { 4037 hist_err(tr, HIST_ERR_SYNTH_COUNT_MISMATCH, errpos(event->name)); 4038 ret = -EINVAL; 4039 goto err; 4040 } 4041 4042 data->synth_event = event; 4043 out: 4044 return ret; 4045 err: 4046 event->ref--; 4047 4048 goto out; 4049 } 4050 4051 static int action_create(struct hist_trigger_data *hist_data, 4052 struct action_data *data) 4053 { 4054 struct trace_event_file *file = hist_data->event_file; 4055 struct trace_array *tr = file->tr; 4056 struct track_data *track_data; 4057 struct field_var *field_var; 4058 unsigned int i; 4059 char *param; 4060 int ret = 0; 4061 4062 if (data->action == ACTION_TRACE) 4063 return trace_action_create(hist_data, data); 4064 4065 if (data->action == ACTION_SNAPSHOT) { 4066 track_data = track_data_alloc(hist_data->key_size, data, hist_data); 4067 if (IS_ERR(track_data)) { 4068 ret = PTR_ERR(track_data); 4069 goto out; 4070 } 4071 4072 ret = tracing_snapshot_cond_enable(file->tr, track_data, 4073 cond_snapshot_update); 4074 if (ret) 4075 track_data_free(track_data); 4076 4077 goto out; 4078 } 4079 4080 if (data->action == ACTION_SAVE) { 4081 if (hist_data->n_save_vars) { 4082 ret = -EEXIST; 4083 hist_err(tr, HIST_ERR_TOO_MANY_SAVE_ACTIONS, 0); 4084 goto out; 4085 } 4086 4087 for (i = 0; i < data->n_params; i++) { 4088 param = kstrdup(data->params[i], GFP_KERNEL); 4089 if (!param) { 4090 ret = -ENOMEM; 4091 goto out; 4092 } 4093 4094 field_var = create_target_field_var(hist_data, NULL, NULL, param); 4095 if (IS_ERR(field_var)) { 4096 hist_err(tr, HIST_ERR_FIELD_VAR_CREATE_FAIL, 4097 errpos(param)); 4098 ret = PTR_ERR(field_var); 4099 kfree(param); 4100 goto out; 4101 } 4102 4103 hist_data->save_vars[hist_data->n_save_vars++] = field_var; 4104 if (field_var->val->flags & HIST_FIELD_FL_STRING) 4105 hist_data->n_save_var_str++; 4106 kfree(param); 4107 } 4108 } 4109 out: 4110 return ret; 4111 } 4112 4113 static int onmatch_create(struct hist_trigger_data *hist_data, 4114 struct action_data *data) 4115 { 4116 return action_create(hist_data, data); 4117 } 4118 4119 static struct action_data *onmatch_parse(struct trace_array *tr, char *str) 4120 { 4121 char *match_event, *match_event_system; 4122 struct action_data *data; 4123 int ret = -EINVAL; 4124 4125 data = kzalloc(sizeof(*data), GFP_KERNEL); 4126 if (!data) 4127 return ERR_PTR(-ENOMEM); 4128 4129 match_event = strsep(&str, ")"); 4130 if (!match_event || !str) { 4131 hist_err(tr, HIST_ERR_NO_CLOSING_PAREN, errpos(match_event)); 4132 goto free; 4133 } 4134 4135 match_event_system = strsep(&match_event, "."); 4136 if (!match_event) { 4137 hist_err(tr, HIST_ERR_SUBSYS_NOT_FOUND, errpos(match_event_system)); 4138 goto free; 4139 } 4140 4141 if (IS_ERR(event_file(tr, match_event_system, match_event))) { 4142 hist_err(tr, HIST_ERR_INVALID_SUBSYS_EVENT, errpos(match_event)); 4143 goto free; 4144 } 4145 4146 data->match_data.event = kstrdup(match_event, GFP_KERNEL); 4147 if (!data->match_data.event) { 4148 ret = -ENOMEM; 4149 goto free; 4150 } 4151 4152 data->match_data.event_system = kstrdup(match_event_system, GFP_KERNEL); 4153 if (!data->match_data.event_system) { 4154 ret = -ENOMEM; 4155 goto free; 4156 } 4157 4158 ret = action_parse(tr, str, data, HANDLER_ONMATCH); 4159 if (ret) 4160 goto free; 4161 out: 4162 return data; 4163 free: 4164 onmatch_destroy(data); 4165 data = ERR_PTR(ret); 4166 goto out; 4167 } 4168 4169 static int create_hitcount_val(struct hist_trigger_data *hist_data) 4170 { 4171 hist_data->fields[HITCOUNT_IDX] = 4172 create_hist_field(hist_data, NULL, HIST_FIELD_FL_HITCOUNT, NULL); 4173 if (!hist_data->fields[HITCOUNT_IDX]) 4174 return -ENOMEM; 4175 4176 hist_data->n_vals++; 4177 hist_data->n_fields++; 4178 4179 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX)) 4180 return -EINVAL; 4181 4182 return 0; 4183 } 4184 4185 static int __create_val_field(struct hist_trigger_data *hist_data, 4186 unsigned int val_idx, 4187 struct trace_event_file *file, 4188 char *var_name, char *field_str, 4189 unsigned long flags) 4190 { 4191 struct hist_field *hist_field; 4192 int ret = 0, n_subexprs = 0; 4193 4194 hist_field = parse_expr(hist_data, file, field_str, flags, var_name, &n_subexprs); 4195 if (IS_ERR(hist_field)) { 4196 ret = PTR_ERR(hist_field); 4197 goto out; 4198 } 4199 4200 hist_data->fields[val_idx] = hist_field; 4201 4202 ++hist_data->n_vals; 4203 ++hist_data->n_fields; 4204 4205 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX)) 4206 ret = -EINVAL; 4207 out: 4208 return ret; 4209 } 4210 4211 static int create_val_field(struct hist_trigger_data *hist_data, 4212 unsigned int val_idx, 4213 struct trace_event_file *file, 4214 char *field_str) 4215 { 4216 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX)) 4217 return -EINVAL; 4218 4219 return __create_val_field(hist_data, val_idx, file, NULL, field_str, 0); 4220 } 4221 4222 static const char no_comm[] = "(no comm)"; 4223 4224 static u64 hist_field_execname(struct hist_field *hist_field, 4225 struct tracing_map_elt *elt, 4226 struct trace_buffer *buffer, 4227 struct ring_buffer_event *rbe, 4228 void *event) 4229 { 4230 struct hist_elt_data *elt_data; 4231 4232 if (WARN_ON_ONCE(!elt)) 4233 return (u64)(unsigned long)no_comm; 4234 4235 elt_data = elt->private_data; 4236 4237 if (WARN_ON_ONCE(!elt_data->comm)) 4238 return (u64)(unsigned long)no_comm; 4239 4240 return (u64)(unsigned long)(elt_data->comm); 4241 } 4242 4243 static u64 hist_fn_call(struct hist_field *hist_field, 4244 struct tracing_map_elt *elt, 4245 struct trace_buffer *buffer, 4246 struct ring_buffer_event *rbe, 4247 void *event) 4248 { 4249 switch (hist_field->fn_num) { 4250 case HIST_FIELD_FN_VAR_REF: 4251 return hist_field_var_ref(hist_field, elt, buffer, rbe, event); 4252 case HIST_FIELD_FN_COUNTER: 4253 return hist_field_counter(hist_field, elt, buffer, rbe, event); 4254 case HIST_FIELD_FN_CONST: 4255 return hist_field_const(hist_field, elt, buffer, rbe, event); 4256 case HIST_FIELD_FN_LOG2: 4257 return hist_field_log2(hist_field, elt, buffer, rbe, event); 4258 case HIST_FIELD_FN_BUCKET: 4259 return hist_field_bucket(hist_field, elt, buffer, rbe, event); 4260 case HIST_FIELD_FN_TIMESTAMP: 4261 return hist_field_timestamp(hist_field, elt, buffer, rbe, event); 4262 case HIST_FIELD_FN_CPU: 4263 return hist_field_cpu(hist_field, elt, buffer, rbe, event); 4264 case HIST_FIELD_FN_STRING: 4265 return hist_field_string(hist_field, elt, buffer, rbe, event); 4266 case HIST_FIELD_FN_DYNSTRING: 4267 return hist_field_dynstring(hist_field, elt, buffer, rbe, event); 4268 case HIST_FIELD_FN_RELDYNSTRING: 4269 return hist_field_reldynstring(hist_field, elt, buffer, rbe, event); 4270 case HIST_FIELD_FN_PSTRING: 4271 return hist_field_pstring(hist_field, elt, buffer, rbe, event); 4272 case HIST_FIELD_FN_S64: 4273 return hist_field_s64(hist_field, elt, buffer, rbe, event); 4274 case HIST_FIELD_FN_U64: 4275 return hist_field_u64(hist_field, elt, buffer, rbe, event); 4276 case HIST_FIELD_FN_S32: 4277 return hist_field_s32(hist_field, elt, buffer, rbe, event); 4278 case HIST_FIELD_FN_U32: 4279 return hist_field_u32(hist_field, elt, buffer, rbe, event); 4280 case HIST_FIELD_FN_S16: 4281 return hist_field_s16(hist_field, elt, buffer, rbe, event); 4282 case HIST_FIELD_FN_U16: 4283 return hist_field_u16(hist_field, elt, buffer, rbe, event); 4284 case HIST_FIELD_FN_S8: 4285 return hist_field_s8(hist_field, elt, buffer, rbe, event); 4286 case HIST_FIELD_FN_U8: 4287 return hist_field_u8(hist_field, elt, buffer, rbe, event); 4288 case HIST_FIELD_FN_UMINUS: 4289 return hist_field_unary_minus(hist_field, elt, buffer, rbe, event); 4290 case HIST_FIELD_FN_MINUS: 4291 return hist_field_minus(hist_field, elt, buffer, rbe, event); 4292 case HIST_FIELD_FN_PLUS: 4293 return hist_field_plus(hist_field, elt, buffer, rbe, event); 4294 case HIST_FIELD_FN_DIV: 4295 return hist_field_div(hist_field, elt, buffer, rbe, event); 4296 case HIST_FIELD_FN_MULT: 4297 return hist_field_mult(hist_field, elt, buffer, rbe, event); 4298 case HIST_FIELD_FN_DIV_POWER2: 4299 return div_by_power_of_two(hist_field, elt, buffer, rbe, event); 4300 case HIST_FIELD_FN_DIV_NOT_POWER2: 4301 return div_by_not_power_of_two(hist_field, elt, buffer, rbe, event); 4302 case HIST_FIELD_FN_DIV_MULT_SHIFT: 4303 return div_by_mult_and_shift(hist_field, elt, buffer, rbe, event); 4304 case HIST_FIELD_FN_EXECNAME: 4305 return hist_field_execname(hist_field, elt, buffer, rbe, event); 4306 default: 4307 return 0; 4308 } 4309 } 4310 4311 /* Convert a var that points to common_pid.execname to a string */ 4312 static void update_var_execname(struct hist_field *hist_field) 4313 { 4314 hist_field->flags = HIST_FIELD_FL_STRING | HIST_FIELD_FL_VAR | 4315 HIST_FIELD_FL_EXECNAME; 4316 hist_field->size = MAX_FILTER_STR_VAL; 4317 hist_field->is_signed = 0; 4318 4319 kfree_const(hist_field->type); 4320 hist_field->type = "char[]"; 4321 4322 hist_field->fn_num = HIST_FIELD_FN_EXECNAME; 4323 } 4324 4325 static int create_var_field(struct hist_trigger_data *hist_data, 4326 unsigned int val_idx, 4327 struct trace_event_file *file, 4328 char *var_name, char *expr_str) 4329 { 4330 struct trace_array *tr = hist_data->event_file->tr; 4331 unsigned long flags = 0; 4332 int ret; 4333 4334 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX)) 4335 return -EINVAL; 4336 4337 if (find_var(hist_data, file, var_name) && !hist_data->remove) { 4338 hist_err(tr, HIST_ERR_DUPLICATE_VAR, errpos(var_name)); 4339 return -EINVAL; 4340 } 4341 4342 flags |= HIST_FIELD_FL_VAR; 4343 hist_data->n_vars++; 4344 if (WARN_ON(hist_data->n_vars > TRACING_MAP_VARS_MAX)) 4345 return -EINVAL; 4346 4347 ret = __create_val_field(hist_data, val_idx, file, var_name, expr_str, flags); 4348 4349 if (!ret && hist_data->fields[val_idx]->flags & HIST_FIELD_FL_EXECNAME) 4350 update_var_execname(hist_data->fields[val_idx]); 4351 4352 if (!ret && hist_data->fields[val_idx]->flags & HIST_FIELD_FL_STRING) 4353 hist_data->fields[val_idx]->var_str_idx = hist_data->n_var_str++; 4354 4355 return ret; 4356 } 4357 4358 static int create_val_fields(struct hist_trigger_data *hist_data, 4359 struct trace_event_file *file) 4360 { 4361 unsigned int i, j = 1, n_hitcount = 0; 4362 char *fields_str, *field_str; 4363 int ret; 4364 4365 ret = create_hitcount_val(hist_data); 4366 if (ret) 4367 goto out; 4368 4369 fields_str = hist_data->attrs->vals_str; 4370 if (!fields_str) 4371 goto out; 4372 4373 for (i = 0, j = 1; i < TRACING_MAP_VALS_MAX && 4374 j < TRACING_MAP_VALS_MAX; i++) { 4375 field_str = strsep(&fields_str, ","); 4376 if (!field_str) 4377 break; 4378 4379 if (strcmp(field_str, "hitcount") == 0) { 4380 if (!n_hitcount++) 4381 continue; 4382 } 4383 4384 ret = create_val_field(hist_data, j++, file, field_str); 4385 if (ret) 4386 goto out; 4387 } 4388 4389 if (fields_str && (strcmp(fields_str, "hitcount") != 0)) 4390 ret = -EINVAL; 4391 out: 4392 /* There is only raw hitcount but nohitcount suppresses it. */ 4393 if (j == 1 && hist_data->attrs->no_hitcount) { 4394 hist_err(hist_data->event_file->tr, HIST_ERR_NEED_NOHC_VAL, 0); 4395 ret = -ENOENT; 4396 } 4397 4398 return ret; 4399 } 4400 4401 static int create_key_field(struct hist_trigger_data *hist_data, 4402 unsigned int key_idx, 4403 unsigned int key_offset, 4404 struct trace_event_file *file, 4405 char *field_str) 4406 { 4407 struct trace_array *tr = hist_data->event_file->tr; 4408 struct hist_field *hist_field = NULL; 4409 unsigned long flags = 0; 4410 unsigned int key_size; 4411 int ret = 0, n_subexprs = 0; 4412 4413 if (WARN_ON(key_idx >= HIST_FIELDS_MAX)) 4414 return -EINVAL; 4415 4416 flags |= HIST_FIELD_FL_KEY; 4417 4418 if (strcmp(field_str, "stacktrace") == 0) { 4419 flags |= HIST_FIELD_FL_STACKTRACE; 4420 key_size = sizeof(unsigned long) * HIST_STACKTRACE_DEPTH; 4421 hist_field = create_hist_field(hist_data, NULL, flags, NULL); 4422 } else { 4423 hist_field = parse_expr(hist_data, file, field_str, flags, 4424 NULL, &n_subexprs); 4425 if (IS_ERR(hist_field)) { 4426 ret = PTR_ERR(hist_field); 4427 goto out; 4428 } 4429 4430 if (field_has_hist_vars(hist_field, 0)) { 4431 hist_err(tr, HIST_ERR_INVALID_REF_KEY, errpos(field_str)); 4432 destroy_hist_field(hist_field, 0); 4433 ret = -EINVAL; 4434 goto out; 4435 } 4436 4437 key_size = hist_field->size; 4438 } 4439 4440 hist_data->fields[key_idx] = hist_field; 4441 4442 key_size = ALIGN(key_size, sizeof(u64)); 4443 hist_data->fields[key_idx]->size = key_size; 4444 hist_data->fields[key_idx]->offset = key_offset; 4445 4446 hist_data->key_size += key_size; 4447 4448 if (hist_data->key_size > HIST_KEY_SIZE_MAX) { 4449 ret = -EINVAL; 4450 goto out; 4451 } 4452 4453 hist_data->n_keys++; 4454 hist_data->n_fields++; 4455 4456 if (WARN_ON(hist_data->n_keys > TRACING_MAP_KEYS_MAX)) 4457 return -EINVAL; 4458 4459 ret = key_size; 4460 out: 4461 return ret; 4462 } 4463 4464 static int create_key_fields(struct hist_trigger_data *hist_data, 4465 struct trace_event_file *file) 4466 { 4467 unsigned int i, key_offset = 0, n_vals = hist_data->n_vals; 4468 char *fields_str, *field_str; 4469 int ret = -EINVAL; 4470 4471 fields_str = hist_data->attrs->keys_str; 4472 if (!fields_str) 4473 goto out; 4474 4475 for (i = n_vals; i < n_vals + TRACING_MAP_KEYS_MAX; i++) { 4476 field_str = strsep(&fields_str, ","); 4477 if (!field_str) 4478 break; 4479 ret = create_key_field(hist_data, i, key_offset, 4480 file, field_str); 4481 if (ret < 0) 4482 goto out; 4483 key_offset += ret; 4484 } 4485 if (fields_str) { 4486 ret = -EINVAL; 4487 goto out; 4488 } 4489 ret = 0; 4490 out: 4491 return ret; 4492 } 4493 4494 static int create_var_fields(struct hist_trigger_data *hist_data, 4495 struct trace_event_file *file) 4496 { 4497 unsigned int i, j = hist_data->n_vals; 4498 int ret = 0; 4499 4500 unsigned int n_vars = hist_data->attrs->var_defs.n_vars; 4501 4502 for (i = 0; i < n_vars; i++) { 4503 char *var_name = hist_data->attrs->var_defs.name[i]; 4504 char *expr = hist_data->attrs->var_defs.expr[i]; 4505 4506 ret = create_var_field(hist_data, j++, file, var_name, expr); 4507 if (ret) 4508 goto out; 4509 } 4510 out: 4511 return ret; 4512 } 4513 4514 static void free_var_defs(struct hist_trigger_data *hist_data) 4515 { 4516 unsigned int i; 4517 4518 for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) { 4519 kfree(hist_data->attrs->var_defs.name[i]); 4520 kfree(hist_data->attrs->var_defs.expr[i]); 4521 } 4522 4523 hist_data->attrs->var_defs.n_vars = 0; 4524 } 4525 4526 static int parse_var_defs(struct hist_trigger_data *hist_data) 4527 { 4528 struct trace_array *tr = hist_data->event_file->tr; 4529 char *s, *str, *var_name, *field_str; 4530 unsigned int i, j, n_vars = 0; 4531 int ret = 0; 4532 4533 for (i = 0; i < hist_data->attrs->n_assignments; i++) { 4534 str = hist_data->attrs->assignment_str[i]; 4535 for (j = 0; j < TRACING_MAP_VARS_MAX; j++) { 4536 field_str = strsep(&str, ","); 4537 if (!field_str) 4538 break; 4539 4540 var_name = strsep(&field_str, "="); 4541 if (!var_name || !field_str) { 4542 hist_err(tr, HIST_ERR_MALFORMED_ASSIGNMENT, 4543 errpos(var_name)); 4544 ret = -EINVAL; 4545 goto free; 4546 } 4547 4548 if (n_vars == TRACING_MAP_VARS_MAX) { 4549 hist_err(tr, HIST_ERR_TOO_MANY_VARS, errpos(var_name)); 4550 ret = -EINVAL; 4551 goto free; 4552 } 4553 4554 s = kstrdup(var_name, GFP_KERNEL); 4555 if (!s) { 4556 ret = -ENOMEM; 4557 goto free; 4558 } 4559 hist_data->attrs->var_defs.name[n_vars] = s; 4560 4561 s = kstrdup(field_str, GFP_KERNEL); 4562 if (!s) { 4563 kfree(hist_data->attrs->var_defs.name[n_vars]); 4564 hist_data->attrs->var_defs.name[n_vars] = NULL; 4565 ret = -ENOMEM; 4566 goto free; 4567 } 4568 hist_data->attrs->var_defs.expr[n_vars++] = s; 4569 4570 hist_data->attrs->var_defs.n_vars = n_vars; 4571 } 4572 } 4573 4574 return ret; 4575 free: 4576 free_var_defs(hist_data); 4577 4578 return ret; 4579 } 4580 4581 static int create_hist_fields(struct hist_trigger_data *hist_data, 4582 struct trace_event_file *file) 4583 { 4584 int ret; 4585 4586 ret = parse_var_defs(hist_data); 4587 if (ret) 4588 return ret; 4589 4590 ret = create_val_fields(hist_data, file); 4591 if (ret) 4592 goto out; 4593 4594 ret = create_var_fields(hist_data, file); 4595 if (ret) 4596 goto out; 4597 4598 ret = create_key_fields(hist_data, file); 4599 4600 out: 4601 free_var_defs(hist_data); 4602 4603 return ret; 4604 } 4605 4606 static int is_descending(struct trace_array *tr, const char *str) 4607 { 4608 if (!str) 4609 return 0; 4610 4611 if (strcmp(str, "descending") == 0) 4612 return 1; 4613 4614 if (strcmp(str, "ascending") == 0) 4615 return 0; 4616 4617 hist_err(tr, HIST_ERR_INVALID_SORT_MODIFIER, errpos((char *)str)); 4618 4619 return -EINVAL; 4620 } 4621 4622 static int create_sort_keys(struct hist_trigger_data *hist_data) 4623 { 4624 struct trace_array *tr = hist_data->event_file->tr; 4625 char *fields_str = hist_data->attrs->sort_key_str; 4626 struct tracing_map_sort_key *sort_key; 4627 int descending, ret = 0; 4628 unsigned int i, j, k; 4629 4630 hist_data->n_sort_keys = 1; /* we always have at least one, hitcount */ 4631 4632 if (!fields_str) 4633 goto out; 4634 4635 for (i = 0; i < TRACING_MAP_SORT_KEYS_MAX; i++) { 4636 struct hist_field *hist_field; 4637 char *field_str, *field_name; 4638 const char *test_name; 4639 4640 sort_key = &hist_data->sort_keys[i]; 4641 4642 field_str = strsep(&fields_str, ","); 4643 if (!field_str) 4644 break; 4645 4646 if (!*field_str) { 4647 ret = -EINVAL; 4648 hist_err(tr, HIST_ERR_EMPTY_SORT_FIELD, errpos("sort=")); 4649 break; 4650 } 4651 4652 if ((i == TRACING_MAP_SORT_KEYS_MAX - 1) && fields_str) { 4653 hist_err(tr, HIST_ERR_TOO_MANY_SORT_FIELDS, errpos("sort=")); 4654 ret = -EINVAL; 4655 break; 4656 } 4657 4658 field_name = strsep(&field_str, "."); 4659 if (!field_name || !*field_name) { 4660 ret = -EINVAL; 4661 hist_err(tr, HIST_ERR_EMPTY_SORT_FIELD, errpos("sort=")); 4662 break; 4663 } 4664 4665 if (strcmp(field_name, "hitcount") == 0) { 4666 descending = is_descending(tr, field_str); 4667 if (descending < 0) { 4668 ret = descending; 4669 break; 4670 } 4671 sort_key->descending = descending; 4672 continue; 4673 } 4674 4675 for (j = 1, k = 1; j < hist_data->n_fields; j++) { 4676 unsigned int idx; 4677 4678 hist_field = hist_data->fields[j]; 4679 if (hist_field->flags & HIST_FIELD_FL_VAR) 4680 continue; 4681 4682 idx = k++; 4683 4684 test_name = hist_field_name(hist_field, 0); 4685 4686 if (strcmp(field_name, test_name) == 0) { 4687 sort_key->field_idx = idx; 4688 descending = is_descending(tr, field_str); 4689 if (descending < 0) { 4690 ret = descending; 4691 goto out; 4692 } 4693 sort_key->descending = descending; 4694 break; 4695 } 4696 } 4697 if (j == hist_data->n_fields) { 4698 ret = -EINVAL; 4699 hist_err(tr, HIST_ERR_INVALID_SORT_FIELD, errpos(field_name)); 4700 break; 4701 } 4702 } 4703 4704 hist_data->n_sort_keys = i; 4705 out: 4706 return ret; 4707 } 4708 4709 static void destroy_actions(struct hist_trigger_data *hist_data) 4710 { 4711 unsigned int i; 4712 4713 for (i = 0; i < hist_data->n_actions; i++) { 4714 struct action_data *data = hist_data->actions[i]; 4715 4716 if (data->handler == HANDLER_ONMATCH) 4717 onmatch_destroy(data); 4718 else if (data->handler == HANDLER_ONMAX || 4719 data->handler == HANDLER_ONCHANGE) 4720 track_data_destroy(hist_data, data); 4721 else 4722 kfree(data); 4723 } 4724 } 4725 4726 static int parse_actions(struct hist_trigger_data *hist_data) 4727 { 4728 struct trace_array *tr = hist_data->event_file->tr; 4729 struct action_data *data; 4730 unsigned int i; 4731 int ret = 0; 4732 char *str; 4733 int len; 4734 4735 for (i = 0; i < hist_data->attrs->n_actions; i++) { 4736 str = hist_data->attrs->action_str[i]; 4737 4738 if ((len = str_has_prefix(str, "onmatch("))) { 4739 char *action_str = str + len; 4740 4741 data = onmatch_parse(tr, action_str); 4742 if (IS_ERR(data)) { 4743 ret = PTR_ERR(data); 4744 break; 4745 } 4746 } else if ((len = str_has_prefix(str, "onmax("))) { 4747 char *action_str = str + len; 4748 4749 data = track_data_parse(hist_data, action_str, 4750 HANDLER_ONMAX); 4751 if (IS_ERR(data)) { 4752 ret = PTR_ERR(data); 4753 break; 4754 } 4755 } else if ((len = str_has_prefix(str, "onchange("))) { 4756 char *action_str = str + len; 4757 4758 data = track_data_parse(hist_data, action_str, 4759 HANDLER_ONCHANGE); 4760 if (IS_ERR(data)) { 4761 ret = PTR_ERR(data); 4762 break; 4763 } 4764 } else { 4765 ret = -EINVAL; 4766 break; 4767 } 4768 4769 hist_data->actions[hist_data->n_actions++] = data; 4770 } 4771 4772 return ret; 4773 } 4774 4775 static int create_actions(struct hist_trigger_data *hist_data) 4776 { 4777 struct action_data *data; 4778 unsigned int i; 4779 int ret = 0; 4780 4781 for (i = 0; i < hist_data->attrs->n_actions; i++) { 4782 data = hist_data->actions[i]; 4783 4784 if (data->handler == HANDLER_ONMATCH) { 4785 ret = onmatch_create(hist_data, data); 4786 if (ret) 4787 break; 4788 } else if (data->handler == HANDLER_ONMAX || 4789 data->handler == HANDLER_ONCHANGE) { 4790 ret = track_data_create(hist_data, data); 4791 if (ret) 4792 break; 4793 } else { 4794 ret = -EINVAL; 4795 break; 4796 } 4797 } 4798 4799 return ret; 4800 } 4801 4802 static void print_actions(struct seq_file *m, 4803 struct hist_trigger_data *hist_data, 4804 struct tracing_map_elt *elt) 4805 { 4806 unsigned int i; 4807 4808 for (i = 0; i < hist_data->n_actions; i++) { 4809 struct action_data *data = hist_data->actions[i]; 4810 4811 if (data->action == ACTION_SNAPSHOT) 4812 continue; 4813 4814 if (data->handler == HANDLER_ONMAX || 4815 data->handler == HANDLER_ONCHANGE) 4816 track_data_print(m, hist_data, elt, data); 4817 } 4818 } 4819 4820 static void print_action_spec(struct seq_file *m, 4821 struct hist_trigger_data *hist_data, 4822 struct action_data *data) 4823 { 4824 unsigned int i; 4825 4826 if (data->action == ACTION_SAVE) { 4827 for (i = 0; i < hist_data->n_save_vars; i++) { 4828 seq_printf(m, "%s", hist_data->save_vars[i]->var->var.name); 4829 if (i < hist_data->n_save_vars - 1) 4830 seq_puts(m, ","); 4831 } 4832 } else if (data->action == ACTION_TRACE) { 4833 if (data->use_trace_keyword) 4834 seq_printf(m, "%s", data->synth_event_name); 4835 for (i = 0; i < data->n_params; i++) { 4836 if (i || data->use_trace_keyword) 4837 seq_puts(m, ","); 4838 seq_printf(m, "%s", data->params[i]); 4839 } 4840 } 4841 } 4842 4843 static void print_track_data_spec(struct seq_file *m, 4844 struct hist_trigger_data *hist_data, 4845 struct action_data *data) 4846 { 4847 if (data->handler == HANDLER_ONMAX) 4848 seq_puts(m, ":onmax("); 4849 else if (data->handler == HANDLER_ONCHANGE) 4850 seq_puts(m, ":onchange("); 4851 seq_printf(m, "%s", data->track_data.var_str); 4852 seq_printf(m, ").%s(", data->action_name); 4853 4854 print_action_spec(m, hist_data, data); 4855 4856 seq_puts(m, ")"); 4857 } 4858 4859 static void print_onmatch_spec(struct seq_file *m, 4860 struct hist_trigger_data *hist_data, 4861 struct action_data *data) 4862 { 4863 seq_printf(m, ":onmatch(%s.%s).", data->match_data.event_system, 4864 data->match_data.event); 4865 4866 seq_printf(m, "%s(", data->action_name); 4867 4868 print_action_spec(m, hist_data, data); 4869 4870 seq_puts(m, ")"); 4871 } 4872 4873 static bool actions_match(struct hist_trigger_data *hist_data, 4874 struct hist_trigger_data *hist_data_test) 4875 { 4876 unsigned int i, j; 4877 4878 if (hist_data->n_actions != hist_data_test->n_actions) 4879 return false; 4880 4881 for (i = 0; i < hist_data->n_actions; i++) { 4882 struct action_data *data = hist_data->actions[i]; 4883 struct action_data *data_test = hist_data_test->actions[i]; 4884 char *action_name, *action_name_test; 4885 4886 if (data->handler != data_test->handler) 4887 return false; 4888 if (data->action != data_test->action) 4889 return false; 4890 4891 if (data->n_params != data_test->n_params) 4892 return false; 4893 4894 for (j = 0; j < data->n_params; j++) { 4895 if (strcmp(data->params[j], data_test->params[j]) != 0) 4896 return false; 4897 } 4898 4899 if (data->use_trace_keyword) 4900 action_name = data->synth_event_name; 4901 else 4902 action_name = data->action_name; 4903 4904 if (data_test->use_trace_keyword) 4905 action_name_test = data_test->synth_event_name; 4906 else 4907 action_name_test = data_test->action_name; 4908 4909 if (strcmp(action_name, action_name_test) != 0) 4910 return false; 4911 4912 if (data->handler == HANDLER_ONMATCH) { 4913 if (strcmp(data->match_data.event_system, 4914 data_test->match_data.event_system) != 0) 4915 return false; 4916 if (strcmp(data->match_data.event, 4917 data_test->match_data.event) != 0) 4918 return false; 4919 } else if (data->handler == HANDLER_ONMAX || 4920 data->handler == HANDLER_ONCHANGE) { 4921 if (strcmp(data->track_data.var_str, 4922 data_test->track_data.var_str) != 0) 4923 return false; 4924 } 4925 } 4926 4927 return true; 4928 } 4929 4930 4931 static void print_actions_spec(struct seq_file *m, 4932 struct hist_trigger_data *hist_data) 4933 { 4934 unsigned int i; 4935 4936 for (i = 0; i < hist_data->n_actions; i++) { 4937 struct action_data *data = hist_data->actions[i]; 4938 4939 if (data->handler == HANDLER_ONMATCH) 4940 print_onmatch_spec(m, hist_data, data); 4941 else if (data->handler == HANDLER_ONMAX || 4942 data->handler == HANDLER_ONCHANGE) 4943 print_track_data_spec(m, hist_data, data); 4944 } 4945 } 4946 4947 static void destroy_field_var_hists(struct hist_trigger_data *hist_data) 4948 { 4949 unsigned int i; 4950 4951 for (i = 0; i < hist_data->n_field_var_hists; i++) { 4952 kfree(hist_data->field_var_hists[i]->cmd); 4953 kfree(hist_data->field_var_hists[i]); 4954 } 4955 } 4956 4957 static void destroy_hist_data(struct hist_trigger_data *hist_data) 4958 { 4959 if (!hist_data) 4960 return; 4961 4962 destroy_hist_trigger_attrs(hist_data->attrs); 4963 destroy_hist_fields(hist_data); 4964 tracing_map_destroy(hist_data->map); 4965 4966 destroy_actions(hist_data); 4967 destroy_field_vars(hist_data); 4968 destroy_field_var_hists(hist_data); 4969 4970 kfree(hist_data); 4971 } 4972 4973 static int create_tracing_map_fields(struct hist_trigger_data *hist_data) 4974 { 4975 struct tracing_map *map = hist_data->map; 4976 struct ftrace_event_field *field; 4977 struct hist_field *hist_field; 4978 int i, idx = 0; 4979 4980 for_each_hist_field(i, hist_data) { 4981 hist_field = hist_data->fields[i]; 4982 if (hist_field->flags & HIST_FIELD_FL_KEY) { 4983 tracing_map_cmp_fn_t cmp_fn; 4984 4985 field = hist_field->field; 4986 4987 if (hist_field->flags & HIST_FIELD_FL_STACKTRACE) 4988 cmp_fn = tracing_map_cmp_none; 4989 else if (!field || hist_field->flags & HIST_FIELD_FL_CPU) 4990 cmp_fn = tracing_map_cmp_num(hist_field->size, 4991 hist_field->is_signed); 4992 else if (is_string_field(field)) 4993 cmp_fn = tracing_map_cmp_string; 4994 else 4995 cmp_fn = tracing_map_cmp_num(field->size, 4996 field->is_signed); 4997 idx = tracing_map_add_key_field(map, 4998 hist_field->offset, 4999 cmp_fn); 5000 } else if (!(hist_field->flags & HIST_FIELD_FL_VAR)) 5001 idx = tracing_map_add_sum_field(map); 5002 5003 if (idx < 0) 5004 return idx; 5005 5006 if (hist_field->flags & HIST_FIELD_FL_VAR) { 5007 idx = tracing_map_add_var(map); 5008 if (idx < 0) 5009 return idx; 5010 hist_field->var.idx = idx; 5011 hist_field->var.hist_data = hist_data; 5012 } 5013 } 5014 5015 return 0; 5016 } 5017 5018 static struct hist_trigger_data * 5019 create_hist_data(unsigned int map_bits, 5020 struct hist_trigger_attrs *attrs, 5021 struct trace_event_file *file, 5022 bool remove) 5023 { 5024 const struct tracing_map_ops *map_ops = NULL; 5025 struct hist_trigger_data *hist_data; 5026 int ret = 0; 5027 5028 hist_data = kzalloc(sizeof(*hist_data), GFP_KERNEL); 5029 if (!hist_data) 5030 return ERR_PTR(-ENOMEM); 5031 5032 hist_data->attrs = attrs; 5033 hist_data->remove = remove; 5034 hist_data->event_file = file; 5035 5036 ret = parse_actions(hist_data); 5037 if (ret) 5038 goto free; 5039 5040 ret = create_hist_fields(hist_data, file); 5041 if (ret) 5042 goto free; 5043 5044 ret = create_sort_keys(hist_data); 5045 if (ret) 5046 goto free; 5047 5048 map_ops = &hist_trigger_elt_data_ops; 5049 5050 hist_data->map = tracing_map_create(map_bits, hist_data->key_size, 5051 map_ops, hist_data); 5052 if (IS_ERR(hist_data->map)) { 5053 ret = PTR_ERR(hist_data->map); 5054 hist_data->map = NULL; 5055 goto free; 5056 } 5057 5058 ret = create_tracing_map_fields(hist_data); 5059 if (ret) 5060 goto free; 5061 out: 5062 return hist_data; 5063 free: 5064 hist_data->attrs = NULL; 5065 5066 destroy_hist_data(hist_data); 5067 5068 hist_data = ERR_PTR(ret); 5069 5070 goto out; 5071 } 5072 5073 static void hist_trigger_elt_update(struct hist_trigger_data *hist_data, 5074 struct tracing_map_elt *elt, 5075 struct trace_buffer *buffer, void *rec, 5076 struct ring_buffer_event *rbe, 5077 u64 *var_ref_vals) 5078 { 5079 struct hist_elt_data *elt_data; 5080 struct hist_field *hist_field; 5081 unsigned int i, var_idx; 5082 u64 hist_val; 5083 5084 elt_data = elt->private_data; 5085 elt_data->var_ref_vals = var_ref_vals; 5086 5087 for_each_hist_val_field(i, hist_data) { 5088 hist_field = hist_data->fields[i]; 5089 hist_val = hist_fn_call(hist_field, elt, buffer, rbe, rec); 5090 if (hist_field->flags & HIST_FIELD_FL_VAR) { 5091 var_idx = hist_field->var.idx; 5092 5093 if (hist_field->flags & HIST_FIELD_FL_STRING) { 5094 unsigned int str_start, var_str_idx, idx; 5095 char *str, *val_str; 5096 unsigned int size; 5097 5098 str_start = hist_data->n_field_var_str + 5099 hist_data->n_save_var_str; 5100 var_str_idx = hist_field->var_str_idx; 5101 idx = str_start + var_str_idx; 5102 5103 str = elt_data->field_var_str[idx]; 5104 val_str = (char *)(uintptr_t)hist_val; 5105 5106 size = min(hist_field->size, STR_VAR_LEN_MAX); 5107 strscpy(str, val_str, size); 5108 5109 hist_val = (u64)(uintptr_t)str; 5110 } 5111 tracing_map_set_var(elt, var_idx, hist_val); 5112 continue; 5113 } 5114 tracing_map_update_sum(elt, i, hist_val); 5115 } 5116 5117 for_each_hist_key_field(i, hist_data) { 5118 hist_field = hist_data->fields[i]; 5119 if (hist_field->flags & HIST_FIELD_FL_VAR) { 5120 hist_val = hist_fn_call(hist_field, elt, buffer, rbe, rec); 5121 var_idx = hist_field->var.idx; 5122 tracing_map_set_var(elt, var_idx, hist_val); 5123 } 5124 } 5125 5126 update_field_vars(hist_data, elt, buffer, rbe, rec); 5127 } 5128 5129 static inline void add_to_key(char *compound_key, void *key, 5130 struct hist_field *key_field, void *rec) 5131 { 5132 size_t size = key_field->size; 5133 5134 if (key_field->flags & HIST_FIELD_FL_STRING) { 5135 struct ftrace_event_field *field; 5136 5137 field = key_field->field; 5138 if (field->filter_type == FILTER_DYN_STRING || 5139 field->filter_type == FILTER_RDYN_STRING) 5140 size = *(u32 *)(rec + field->offset) >> 16; 5141 else if (field->filter_type == FILTER_STATIC_STRING) 5142 size = field->size; 5143 5144 /* ensure NULL-termination */ 5145 if (size > key_field->size - 1) 5146 size = key_field->size - 1; 5147 5148 strncpy(compound_key + key_field->offset, (char *)key, size); 5149 } else 5150 memcpy(compound_key + key_field->offset, key, size); 5151 } 5152 5153 static void 5154 hist_trigger_actions(struct hist_trigger_data *hist_data, 5155 struct tracing_map_elt *elt, 5156 struct trace_buffer *buffer, void *rec, 5157 struct ring_buffer_event *rbe, void *key, 5158 u64 *var_ref_vals) 5159 { 5160 struct action_data *data; 5161 unsigned int i; 5162 5163 for (i = 0; i < hist_data->n_actions; i++) { 5164 data = hist_data->actions[i]; 5165 data->fn(hist_data, elt, buffer, rec, rbe, key, data, var_ref_vals); 5166 } 5167 } 5168 5169 static void event_hist_trigger(struct event_trigger_data *data, 5170 struct trace_buffer *buffer, void *rec, 5171 struct ring_buffer_event *rbe) 5172 { 5173 struct hist_trigger_data *hist_data = data->private_data; 5174 bool use_compound_key = (hist_data->n_keys > 1); 5175 unsigned long entries[HIST_STACKTRACE_DEPTH]; 5176 u64 var_ref_vals[TRACING_MAP_VARS_MAX]; 5177 char compound_key[HIST_KEY_SIZE_MAX]; 5178 struct tracing_map_elt *elt = NULL; 5179 struct hist_field *key_field; 5180 u64 field_contents; 5181 void *key = NULL; 5182 unsigned int i; 5183 5184 if (unlikely(!rbe)) 5185 return; 5186 5187 memset(compound_key, 0, hist_data->key_size); 5188 5189 for_each_hist_key_field(i, hist_data) { 5190 key_field = hist_data->fields[i]; 5191 5192 if (key_field->flags & HIST_FIELD_FL_STACKTRACE) { 5193 memset(entries, 0, HIST_STACKTRACE_SIZE); 5194 stack_trace_save(entries, HIST_STACKTRACE_DEPTH, 5195 HIST_STACKTRACE_SKIP); 5196 key = entries; 5197 } else { 5198 field_contents = hist_fn_call(key_field, elt, buffer, rbe, rec); 5199 if (key_field->flags & HIST_FIELD_FL_STRING) { 5200 key = (void *)(unsigned long)field_contents; 5201 use_compound_key = true; 5202 } else 5203 key = (void *)&field_contents; 5204 } 5205 5206 if (use_compound_key) 5207 add_to_key(compound_key, key, key_field, rec); 5208 } 5209 5210 if (use_compound_key) 5211 key = compound_key; 5212 5213 if (hist_data->n_var_refs && 5214 !resolve_var_refs(hist_data, key, var_ref_vals, false)) 5215 return; 5216 5217 elt = tracing_map_insert(hist_data->map, key); 5218 if (!elt) 5219 return; 5220 5221 hist_trigger_elt_update(hist_data, elt, buffer, rec, rbe, var_ref_vals); 5222 5223 if (resolve_var_refs(hist_data, key, var_ref_vals, true)) 5224 hist_trigger_actions(hist_data, elt, buffer, rec, rbe, key, var_ref_vals); 5225 } 5226 5227 static void hist_trigger_stacktrace_print(struct seq_file *m, 5228 unsigned long *stacktrace_entries, 5229 unsigned int max_entries) 5230 { 5231 unsigned int spaces = 8; 5232 unsigned int i; 5233 5234 for (i = 0; i < max_entries; i++) { 5235 if (!stacktrace_entries[i]) 5236 return; 5237 5238 seq_printf(m, "%*c", 1 + spaces, ' '); 5239 seq_printf(m, "%pS\n", (void*)stacktrace_entries[i]); 5240 } 5241 } 5242 5243 static void hist_trigger_print_key(struct seq_file *m, 5244 struct hist_trigger_data *hist_data, 5245 void *key, 5246 struct tracing_map_elt *elt) 5247 { 5248 struct hist_field *key_field; 5249 bool multiline = false; 5250 const char *field_name; 5251 unsigned int i; 5252 u64 uval; 5253 5254 seq_puts(m, "{ "); 5255 5256 for_each_hist_key_field(i, hist_data) { 5257 key_field = hist_data->fields[i]; 5258 5259 if (i > hist_data->n_vals) 5260 seq_puts(m, ", "); 5261 5262 field_name = hist_field_name(key_field, 0); 5263 5264 if (key_field->flags & HIST_FIELD_FL_HEX) { 5265 uval = *(u64 *)(key + key_field->offset); 5266 seq_printf(m, "%s: %llx", field_name, uval); 5267 } else if (key_field->flags & HIST_FIELD_FL_SYM) { 5268 uval = *(u64 *)(key + key_field->offset); 5269 seq_printf(m, "%s: [%llx] %-45ps", field_name, 5270 uval, (void *)(uintptr_t)uval); 5271 } else if (key_field->flags & HIST_FIELD_FL_SYM_OFFSET) { 5272 uval = *(u64 *)(key + key_field->offset); 5273 seq_printf(m, "%s: [%llx] %-55pS", field_name, 5274 uval, (void *)(uintptr_t)uval); 5275 } else if (key_field->flags & HIST_FIELD_FL_EXECNAME) { 5276 struct hist_elt_data *elt_data = elt->private_data; 5277 char *comm; 5278 5279 if (WARN_ON_ONCE(!elt_data)) 5280 return; 5281 5282 comm = elt_data->comm; 5283 5284 uval = *(u64 *)(key + key_field->offset); 5285 seq_printf(m, "%s: %-16s[%10llu]", field_name, 5286 comm, uval); 5287 } else if (key_field->flags & HIST_FIELD_FL_SYSCALL) { 5288 const char *syscall_name; 5289 5290 uval = *(u64 *)(key + key_field->offset); 5291 syscall_name = get_syscall_name(uval); 5292 if (!syscall_name) 5293 syscall_name = "unknown_syscall"; 5294 5295 seq_printf(m, "%s: %-30s[%3llu]", field_name, 5296 syscall_name, uval); 5297 } else if (key_field->flags & HIST_FIELD_FL_STACKTRACE) { 5298 seq_puts(m, "stacktrace:\n"); 5299 hist_trigger_stacktrace_print(m, 5300 key + key_field->offset, 5301 HIST_STACKTRACE_DEPTH); 5302 multiline = true; 5303 } else if (key_field->flags & HIST_FIELD_FL_LOG2) { 5304 seq_printf(m, "%s: ~ 2^%-2llu", field_name, 5305 *(u64 *)(key + key_field->offset)); 5306 } else if (key_field->flags & HIST_FIELD_FL_BUCKET) { 5307 unsigned long buckets = key_field->buckets; 5308 uval = *(u64 *)(key + key_field->offset); 5309 seq_printf(m, "%s: ~ %llu-%llu", field_name, 5310 uval, uval + buckets -1); 5311 } else if (key_field->flags & HIST_FIELD_FL_STRING) { 5312 seq_printf(m, "%s: %-50s", field_name, 5313 (char *)(key + key_field->offset)); 5314 } else { 5315 uval = *(u64 *)(key + key_field->offset); 5316 seq_printf(m, "%s: %10llu", field_name, uval); 5317 } 5318 } 5319 5320 if (!multiline) 5321 seq_puts(m, " "); 5322 5323 seq_puts(m, "}"); 5324 } 5325 5326 /* Get the 100 times of the percentage of @val in @total */ 5327 static inline unsigned int __get_percentage(u64 val, u64 total) 5328 { 5329 if (!total) 5330 goto div0; 5331 5332 if (val < (U64_MAX / 10000)) 5333 return (unsigned int)div64_ul(val * 10000, total); 5334 5335 total = div64_u64(total, 10000); 5336 if (!total) 5337 goto div0; 5338 5339 return (unsigned int)div64_ul(val, total); 5340 div0: 5341 return val ? UINT_MAX : 0; 5342 } 5343 5344 #define BAR_CHAR '#' 5345 5346 static inline const char *__fill_bar_str(char *buf, int size, u64 val, u64 max) 5347 { 5348 unsigned int len = __get_percentage(val, max); 5349 int i; 5350 5351 if (len == UINT_MAX) { 5352 snprintf(buf, size, "[ERROR]"); 5353 return buf; 5354 } 5355 5356 len = len * size / 10000; 5357 for (i = 0; i < len && i < size; i++) 5358 buf[i] = BAR_CHAR; 5359 while (i < size) 5360 buf[i++] = ' '; 5361 buf[size] = '\0'; 5362 5363 return buf; 5364 } 5365 5366 struct hist_val_stat { 5367 u64 max; 5368 u64 total; 5369 }; 5370 5371 static void hist_trigger_print_val(struct seq_file *m, unsigned int idx, 5372 const char *field_name, unsigned long flags, 5373 struct hist_val_stat *stats, 5374 struct tracing_map_elt *elt) 5375 { 5376 u64 val = tracing_map_read_sum(elt, idx); 5377 unsigned int pc; 5378 char bar[21]; 5379 5380 if (flags & HIST_FIELD_FL_PERCENT) { 5381 pc = __get_percentage(val, stats[idx].total); 5382 if (pc == UINT_MAX) 5383 seq_printf(m, " %s (%%):[ERROR]", field_name); 5384 else 5385 seq_printf(m, " %s (%%): %3u.%02u", field_name, 5386 pc / 100, pc % 100); 5387 } else if (flags & HIST_FIELD_FL_GRAPH) { 5388 seq_printf(m, " %s: %20s", field_name, 5389 __fill_bar_str(bar, 20, val, stats[idx].max)); 5390 } else if (flags & HIST_FIELD_FL_HEX) { 5391 seq_printf(m, " %s: %10llx", field_name, val); 5392 } else { 5393 seq_printf(m, " %s: %10llu", field_name, val); 5394 } 5395 } 5396 5397 static void hist_trigger_entry_print(struct seq_file *m, 5398 struct hist_trigger_data *hist_data, 5399 struct hist_val_stat *stats, 5400 void *key, 5401 struct tracing_map_elt *elt) 5402 { 5403 const char *field_name; 5404 unsigned int i = HITCOUNT_IDX; 5405 unsigned long flags; 5406 5407 hist_trigger_print_key(m, hist_data, key, elt); 5408 5409 /* At first, show the raw hitcount if !nohitcount */ 5410 if (!hist_data->attrs->no_hitcount) 5411 hist_trigger_print_val(m, i, "hitcount", 0, stats, elt); 5412 5413 for (i = 1; i < hist_data->n_vals; i++) { 5414 field_name = hist_field_name(hist_data->fields[i], 0); 5415 flags = hist_data->fields[i]->flags; 5416 if (flags & HIST_FIELD_FL_VAR || flags & HIST_FIELD_FL_EXPR) 5417 continue; 5418 5419 seq_puts(m, " "); 5420 hist_trigger_print_val(m, i, field_name, flags, stats, elt); 5421 } 5422 5423 print_actions(m, hist_data, elt); 5424 5425 seq_puts(m, "\n"); 5426 } 5427 5428 static int print_entries(struct seq_file *m, 5429 struct hist_trigger_data *hist_data) 5430 { 5431 struct tracing_map_sort_entry **sort_entries = NULL; 5432 struct tracing_map *map = hist_data->map; 5433 int i, j, n_entries; 5434 struct hist_val_stat *stats = NULL; 5435 u64 val; 5436 5437 n_entries = tracing_map_sort_entries(map, hist_data->sort_keys, 5438 hist_data->n_sort_keys, 5439 &sort_entries); 5440 if (n_entries < 0) 5441 return n_entries; 5442 5443 /* Calculate the max and the total for each field if needed. */ 5444 for (j = 0; j < hist_data->n_vals; j++) { 5445 if (!(hist_data->fields[j]->flags & 5446 (HIST_FIELD_FL_PERCENT | HIST_FIELD_FL_GRAPH))) 5447 continue; 5448 if (!stats) { 5449 stats = kcalloc(hist_data->n_vals, sizeof(*stats), 5450 GFP_KERNEL); 5451 if (!stats) { 5452 n_entries = -ENOMEM; 5453 goto out; 5454 } 5455 } 5456 for (i = 0; i < n_entries; i++) { 5457 val = tracing_map_read_sum(sort_entries[i]->elt, j); 5458 stats[j].total += val; 5459 if (stats[j].max < val) 5460 stats[j].max = val; 5461 } 5462 } 5463 5464 for (i = 0; i < n_entries; i++) 5465 hist_trigger_entry_print(m, hist_data, stats, 5466 sort_entries[i]->key, 5467 sort_entries[i]->elt); 5468 5469 kfree(stats); 5470 out: 5471 tracing_map_destroy_sort_entries(sort_entries, n_entries); 5472 5473 return n_entries; 5474 } 5475 5476 static void hist_trigger_show(struct seq_file *m, 5477 struct event_trigger_data *data, int n) 5478 { 5479 struct hist_trigger_data *hist_data; 5480 int n_entries; 5481 5482 if (n > 0) 5483 seq_puts(m, "\n\n"); 5484 5485 seq_puts(m, "# event histogram\n#\n# trigger info: "); 5486 data->ops->print(m, data); 5487 seq_puts(m, "#\n\n"); 5488 5489 hist_data = data->private_data; 5490 n_entries = print_entries(m, hist_data); 5491 if (n_entries < 0) 5492 n_entries = 0; 5493 5494 track_data_snapshot_print(m, hist_data); 5495 5496 seq_printf(m, "\nTotals:\n Hits: %llu\n Entries: %u\n Dropped: %llu\n", 5497 (u64)atomic64_read(&hist_data->map->hits), 5498 n_entries, (u64)atomic64_read(&hist_data->map->drops)); 5499 } 5500 5501 static int hist_show(struct seq_file *m, void *v) 5502 { 5503 struct event_trigger_data *data; 5504 struct trace_event_file *event_file; 5505 int n = 0, ret = 0; 5506 5507 mutex_lock(&event_mutex); 5508 5509 event_file = event_file_data(m->private); 5510 if (unlikely(!event_file)) { 5511 ret = -ENODEV; 5512 goto out_unlock; 5513 } 5514 5515 list_for_each_entry(data, &event_file->triggers, list) { 5516 if (data->cmd_ops->trigger_type == ETT_EVENT_HIST) 5517 hist_trigger_show(m, data, n++); 5518 } 5519 5520 out_unlock: 5521 mutex_unlock(&event_mutex); 5522 5523 return ret; 5524 } 5525 5526 static int event_hist_open(struct inode *inode, struct file *file) 5527 { 5528 int ret; 5529 5530 ret = security_locked_down(LOCKDOWN_TRACEFS); 5531 if (ret) 5532 return ret; 5533 5534 return single_open(file, hist_show, file); 5535 } 5536 5537 const struct file_operations event_hist_fops = { 5538 .open = event_hist_open, 5539 .read = seq_read, 5540 .llseek = seq_lseek, 5541 .release = single_release, 5542 }; 5543 5544 #ifdef CONFIG_HIST_TRIGGERS_DEBUG 5545 static void hist_field_debug_show_flags(struct seq_file *m, 5546 unsigned long flags) 5547 { 5548 seq_puts(m, " flags:\n"); 5549 5550 if (flags & HIST_FIELD_FL_KEY) 5551 seq_puts(m, " HIST_FIELD_FL_KEY\n"); 5552 else if (flags & HIST_FIELD_FL_HITCOUNT) 5553 seq_puts(m, " VAL: HIST_FIELD_FL_HITCOUNT\n"); 5554 else if (flags & HIST_FIELD_FL_VAR) 5555 seq_puts(m, " HIST_FIELD_FL_VAR\n"); 5556 else if (flags & HIST_FIELD_FL_VAR_REF) 5557 seq_puts(m, " HIST_FIELD_FL_VAR_REF\n"); 5558 else 5559 seq_puts(m, " VAL: normal u64 value\n"); 5560 5561 if (flags & HIST_FIELD_FL_ALIAS) 5562 seq_puts(m, " HIST_FIELD_FL_ALIAS\n"); 5563 else if (flags & HIST_FIELD_FL_CONST) 5564 seq_puts(m, " HIST_FIELD_FL_CONST\n"); 5565 } 5566 5567 static int hist_field_debug_show(struct seq_file *m, 5568 struct hist_field *field, unsigned long flags) 5569 { 5570 if ((field->flags & flags) != flags) { 5571 seq_printf(m, "ERROR: bad flags - %lx\n", flags); 5572 return -EINVAL; 5573 } 5574 5575 hist_field_debug_show_flags(m, field->flags); 5576 if (field->field) 5577 seq_printf(m, " ftrace_event_field name: %s\n", 5578 field->field->name); 5579 5580 if (field->flags & HIST_FIELD_FL_VAR) { 5581 seq_printf(m, " var.name: %s\n", field->var.name); 5582 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n", 5583 field->var.idx); 5584 } 5585 5586 if (field->flags & HIST_FIELD_FL_CONST) 5587 seq_printf(m, " constant: %llu\n", field->constant); 5588 5589 if (field->flags & HIST_FIELD_FL_ALIAS) 5590 seq_printf(m, " var_ref_idx (into hist_data->var_refs[]): %u\n", 5591 field->var_ref_idx); 5592 5593 if (field->flags & HIST_FIELD_FL_VAR_REF) { 5594 seq_printf(m, " name: %s\n", field->name); 5595 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n", 5596 field->var.idx); 5597 seq_printf(m, " var.hist_data: %p\n", field->var.hist_data); 5598 seq_printf(m, " var_ref_idx (into hist_data->var_refs[]): %u\n", 5599 field->var_ref_idx); 5600 if (field->system) 5601 seq_printf(m, " system: %s\n", field->system); 5602 if (field->event_name) 5603 seq_printf(m, " event_name: %s\n", field->event_name); 5604 } 5605 5606 seq_printf(m, " type: %s\n", field->type); 5607 seq_printf(m, " size: %u\n", field->size); 5608 seq_printf(m, " is_signed: %u\n", field->is_signed); 5609 5610 return 0; 5611 } 5612 5613 static int field_var_debug_show(struct seq_file *m, 5614 struct field_var *field_var, unsigned int i, 5615 bool save_vars) 5616 { 5617 const char *vars_name = save_vars ? "save_vars" : "field_vars"; 5618 struct hist_field *field; 5619 int ret = 0; 5620 5621 seq_printf(m, "\n hist_data->%s[%d]:\n", vars_name, i); 5622 5623 field = field_var->var; 5624 5625 seq_printf(m, "\n %s[%d].var:\n", vars_name, i); 5626 5627 hist_field_debug_show_flags(m, field->flags); 5628 seq_printf(m, " var.name: %s\n", field->var.name); 5629 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n", 5630 field->var.idx); 5631 5632 field = field_var->val; 5633 5634 seq_printf(m, "\n %s[%d].val:\n", vars_name, i); 5635 if (field->field) 5636 seq_printf(m, " ftrace_event_field name: %s\n", 5637 field->field->name); 5638 else { 5639 ret = -EINVAL; 5640 goto out; 5641 } 5642 5643 seq_printf(m, " type: %s\n", field->type); 5644 seq_printf(m, " size: %u\n", field->size); 5645 seq_printf(m, " is_signed: %u\n", field->is_signed); 5646 out: 5647 return ret; 5648 } 5649 5650 static int hist_action_debug_show(struct seq_file *m, 5651 struct action_data *data, int i) 5652 { 5653 int ret = 0; 5654 5655 if (data->handler == HANDLER_ONMAX || 5656 data->handler == HANDLER_ONCHANGE) { 5657 seq_printf(m, "\n hist_data->actions[%d].track_data.var_ref:\n", i); 5658 ret = hist_field_debug_show(m, data->track_data.var_ref, 5659 HIST_FIELD_FL_VAR_REF); 5660 if (ret) 5661 goto out; 5662 5663 seq_printf(m, "\n hist_data->actions[%d].track_data.track_var:\n", i); 5664 ret = hist_field_debug_show(m, data->track_data.track_var, 5665 HIST_FIELD_FL_VAR); 5666 if (ret) 5667 goto out; 5668 } 5669 5670 if (data->handler == HANDLER_ONMATCH) { 5671 seq_printf(m, "\n hist_data->actions[%d].match_data.event_system: %s\n", 5672 i, data->match_data.event_system); 5673 seq_printf(m, " hist_data->actions[%d].match_data.event: %s\n", 5674 i, data->match_data.event); 5675 } 5676 out: 5677 return ret; 5678 } 5679 5680 static int hist_actions_debug_show(struct seq_file *m, 5681 struct hist_trigger_data *hist_data) 5682 { 5683 int i, ret = 0; 5684 5685 if (hist_data->n_actions) 5686 seq_puts(m, "\n action tracking variables (for onmax()/onchange()/onmatch()):\n"); 5687 5688 for (i = 0; i < hist_data->n_actions; i++) { 5689 struct action_data *action = hist_data->actions[i]; 5690 5691 ret = hist_action_debug_show(m, action, i); 5692 if (ret) 5693 goto out; 5694 } 5695 5696 if (hist_data->n_save_vars) 5697 seq_puts(m, "\n save action variables (save() params):\n"); 5698 5699 for (i = 0; i < hist_data->n_save_vars; i++) { 5700 ret = field_var_debug_show(m, hist_data->save_vars[i], i, true); 5701 if (ret) 5702 goto out; 5703 } 5704 out: 5705 return ret; 5706 } 5707 5708 static void hist_trigger_debug_show(struct seq_file *m, 5709 struct event_trigger_data *data, int n) 5710 { 5711 struct hist_trigger_data *hist_data; 5712 int i, ret; 5713 5714 if (n > 0) 5715 seq_puts(m, "\n\n"); 5716 5717 seq_puts(m, "# event histogram\n#\n# trigger info: "); 5718 data->ops->print(m, data); 5719 seq_puts(m, "#\n\n"); 5720 5721 hist_data = data->private_data; 5722 5723 seq_printf(m, "hist_data: %p\n\n", hist_data); 5724 seq_printf(m, " n_vals: %u\n", hist_data->n_vals); 5725 seq_printf(m, " n_keys: %u\n", hist_data->n_keys); 5726 seq_printf(m, " n_fields: %u\n", hist_data->n_fields); 5727 5728 seq_puts(m, "\n val fields:\n\n"); 5729 5730 seq_puts(m, " hist_data->fields[0]:\n"); 5731 ret = hist_field_debug_show(m, hist_data->fields[0], 5732 HIST_FIELD_FL_HITCOUNT); 5733 if (ret) 5734 return; 5735 5736 for (i = 1; i < hist_data->n_vals; i++) { 5737 seq_printf(m, "\n hist_data->fields[%d]:\n", i); 5738 ret = hist_field_debug_show(m, hist_data->fields[i], 0); 5739 if (ret) 5740 return; 5741 } 5742 5743 seq_puts(m, "\n key fields:\n"); 5744 5745 for (i = hist_data->n_vals; i < hist_data->n_fields; i++) { 5746 seq_printf(m, "\n hist_data->fields[%d]:\n", i); 5747 ret = hist_field_debug_show(m, hist_data->fields[i], 5748 HIST_FIELD_FL_KEY); 5749 if (ret) 5750 return; 5751 } 5752 5753 if (hist_data->n_var_refs) 5754 seq_puts(m, "\n variable reference fields:\n"); 5755 5756 for (i = 0; i < hist_data->n_var_refs; i++) { 5757 seq_printf(m, "\n hist_data->var_refs[%d]:\n", i); 5758 ret = hist_field_debug_show(m, hist_data->var_refs[i], 5759 HIST_FIELD_FL_VAR_REF); 5760 if (ret) 5761 return; 5762 } 5763 5764 if (hist_data->n_field_vars) 5765 seq_puts(m, "\n field variables:\n"); 5766 5767 for (i = 0; i < hist_data->n_field_vars; i++) { 5768 ret = field_var_debug_show(m, hist_data->field_vars[i], i, false); 5769 if (ret) 5770 return; 5771 } 5772 5773 ret = hist_actions_debug_show(m, hist_data); 5774 if (ret) 5775 return; 5776 } 5777 5778 static int hist_debug_show(struct seq_file *m, void *v) 5779 { 5780 struct event_trigger_data *data; 5781 struct trace_event_file *event_file; 5782 int n = 0, ret = 0; 5783 5784 mutex_lock(&event_mutex); 5785 5786 event_file = event_file_data(m->private); 5787 if (unlikely(!event_file)) { 5788 ret = -ENODEV; 5789 goto out_unlock; 5790 } 5791 5792 list_for_each_entry(data, &event_file->triggers, list) { 5793 if (data->cmd_ops->trigger_type == ETT_EVENT_HIST) 5794 hist_trigger_debug_show(m, data, n++); 5795 } 5796 5797 out_unlock: 5798 mutex_unlock(&event_mutex); 5799 5800 return ret; 5801 } 5802 5803 static int event_hist_debug_open(struct inode *inode, struct file *file) 5804 { 5805 int ret; 5806 5807 ret = security_locked_down(LOCKDOWN_TRACEFS); 5808 if (ret) 5809 return ret; 5810 5811 return single_open(file, hist_debug_show, file); 5812 } 5813 5814 const struct file_operations event_hist_debug_fops = { 5815 .open = event_hist_debug_open, 5816 .read = seq_read, 5817 .llseek = seq_lseek, 5818 .release = single_release, 5819 }; 5820 #endif 5821 5822 static void hist_field_print(struct seq_file *m, struct hist_field *hist_field) 5823 { 5824 const char *field_name = hist_field_name(hist_field, 0); 5825 5826 if (hist_field->var.name) 5827 seq_printf(m, "%s=", hist_field->var.name); 5828 5829 if (hist_field->flags & HIST_FIELD_FL_CPU) 5830 seq_puts(m, "common_cpu"); 5831 else if (hist_field->flags & HIST_FIELD_FL_CONST) 5832 seq_printf(m, "%llu", hist_field->constant); 5833 else if (field_name) { 5834 if (hist_field->flags & HIST_FIELD_FL_VAR_REF || 5835 hist_field->flags & HIST_FIELD_FL_ALIAS) 5836 seq_putc(m, '$'); 5837 seq_printf(m, "%s", field_name); 5838 } else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP) 5839 seq_puts(m, "common_timestamp"); 5840 5841 if (hist_field->flags) { 5842 if (!(hist_field->flags & HIST_FIELD_FL_VAR_REF) && 5843 !(hist_field->flags & HIST_FIELD_FL_EXPR)) { 5844 const char *flags = get_hist_field_flags(hist_field); 5845 5846 if (flags) 5847 seq_printf(m, ".%s", flags); 5848 } 5849 } 5850 if (hist_field->buckets) 5851 seq_printf(m, "=%ld", hist_field->buckets); 5852 } 5853 5854 static int event_hist_trigger_print(struct seq_file *m, 5855 struct event_trigger_data *data) 5856 { 5857 struct hist_trigger_data *hist_data = data->private_data; 5858 struct hist_field *field; 5859 bool have_var = false; 5860 bool show_val = false; 5861 unsigned int i; 5862 5863 seq_puts(m, HIST_PREFIX); 5864 5865 if (data->name) 5866 seq_printf(m, "%s:", data->name); 5867 5868 seq_puts(m, "keys="); 5869 5870 for_each_hist_key_field(i, hist_data) { 5871 field = hist_data->fields[i]; 5872 5873 if (i > hist_data->n_vals) 5874 seq_puts(m, ","); 5875 5876 if (field->flags & HIST_FIELD_FL_STACKTRACE) 5877 seq_puts(m, "stacktrace"); 5878 else 5879 hist_field_print(m, field); 5880 } 5881 5882 seq_puts(m, ":vals="); 5883 5884 for_each_hist_val_field(i, hist_data) { 5885 field = hist_data->fields[i]; 5886 if (field->flags & HIST_FIELD_FL_VAR) { 5887 have_var = true; 5888 continue; 5889 } 5890 5891 if (i == HITCOUNT_IDX) { 5892 if (hist_data->attrs->no_hitcount) 5893 continue; 5894 seq_puts(m, "hitcount"); 5895 } else { 5896 if (show_val) 5897 seq_puts(m, ","); 5898 hist_field_print(m, field); 5899 } 5900 show_val = true; 5901 } 5902 5903 if (have_var) { 5904 unsigned int n = 0; 5905 5906 seq_puts(m, ":"); 5907 5908 for_each_hist_val_field(i, hist_data) { 5909 field = hist_data->fields[i]; 5910 5911 if (field->flags & HIST_FIELD_FL_VAR) { 5912 if (n++) 5913 seq_puts(m, ","); 5914 hist_field_print(m, field); 5915 } 5916 } 5917 } 5918 5919 seq_puts(m, ":sort="); 5920 5921 for (i = 0; i < hist_data->n_sort_keys; i++) { 5922 struct tracing_map_sort_key *sort_key; 5923 unsigned int idx, first_key_idx; 5924 5925 /* skip VAR vals */ 5926 first_key_idx = hist_data->n_vals - hist_data->n_vars; 5927 5928 sort_key = &hist_data->sort_keys[i]; 5929 idx = sort_key->field_idx; 5930 5931 if (WARN_ON(idx >= HIST_FIELDS_MAX)) 5932 return -EINVAL; 5933 5934 if (i > 0) 5935 seq_puts(m, ","); 5936 5937 if (idx == HITCOUNT_IDX) 5938 seq_puts(m, "hitcount"); 5939 else { 5940 if (idx >= first_key_idx) 5941 idx += hist_data->n_vars; 5942 hist_field_print(m, hist_data->fields[idx]); 5943 } 5944 5945 if (sort_key->descending) 5946 seq_puts(m, ".descending"); 5947 } 5948 seq_printf(m, ":size=%u", (1 << hist_data->map->map_bits)); 5949 if (hist_data->enable_timestamps) 5950 seq_printf(m, ":clock=%s", hist_data->attrs->clock); 5951 if (hist_data->attrs->no_hitcount) 5952 seq_puts(m, ":nohitcount"); 5953 5954 print_actions_spec(m, hist_data); 5955 5956 if (data->filter_str) 5957 seq_printf(m, " if %s", data->filter_str); 5958 5959 if (data->paused) 5960 seq_puts(m, " [paused]"); 5961 else 5962 seq_puts(m, " [active]"); 5963 5964 seq_putc(m, '\n'); 5965 5966 return 0; 5967 } 5968 5969 static int event_hist_trigger_init(struct event_trigger_data *data) 5970 { 5971 struct hist_trigger_data *hist_data = data->private_data; 5972 5973 if (!data->ref && hist_data->attrs->name) 5974 save_named_trigger(hist_data->attrs->name, data); 5975 5976 data->ref++; 5977 5978 return 0; 5979 } 5980 5981 static void unregister_field_var_hists(struct hist_trigger_data *hist_data) 5982 { 5983 struct trace_event_file *file; 5984 unsigned int i; 5985 char *cmd; 5986 int ret; 5987 5988 for (i = 0; i < hist_data->n_field_var_hists; i++) { 5989 file = hist_data->field_var_hists[i]->hist_data->event_file; 5990 cmd = hist_data->field_var_hists[i]->cmd; 5991 ret = event_hist_trigger_parse(&trigger_hist_cmd, file, 5992 "!hist", "hist", cmd); 5993 WARN_ON_ONCE(ret < 0); 5994 } 5995 } 5996 5997 static void event_hist_trigger_free(struct event_trigger_data *data) 5998 { 5999 struct hist_trigger_data *hist_data = data->private_data; 6000 6001 if (WARN_ON_ONCE(data->ref <= 0)) 6002 return; 6003 6004 data->ref--; 6005 if (!data->ref) { 6006 if (data->name) 6007 del_named_trigger(data); 6008 6009 trigger_data_free(data); 6010 6011 remove_hist_vars(hist_data); 6012 6013 unregister_field_var_hists(hist_data); 6014 6015 destroy_hist_data(hist_data); 6016 } 6017 } 6018 6019 static struct event_trigger_ops event_hist_trigger_ops = { 6020 .trigger = event_hist_trigger, 6021 .print = event_hist_trigger_print, 6022 .init = event_hist_trigger_init, 6023 .free = event_hist_trigger_free, 6024 }; 6025 6026 static int event_hist_trigger_named_init(struct event_trigger_data *data) 6027 { 6028 data->ref++; 6029 6030 save_named_trigger(data->named_data->name, data); 6031 6032 event_hist_trigger_init(data->named_data); 6033 6034 return 0; 6035 } 6036 6037 static void event_hist_trigger_named_free(struct event_trigger_data *data) 6038 { 6039 if (WARN_ON_ONCE(data->ref <= 0)) 6040 return; 6041 6042 event_hist_trigger_free(data->named_data); 6043 6044 data->ref--; 6045 if (!data->ref) { 6046 del_named_trigger(data); 6047 trigger_data_free(data); 6048 } 6049 } 6050 6051 static struct event_trigger_ops event_hist_trigger_named_ops = { 6052 .trigger = event_hist_trigger, 6053 .print = event_hist_trigger_print, 6054 .init = event_hist_trigger_named_init, 6055 .free = event_hist_trigger_named_free, 6056 }; 6057 6058 static struct event_trigger_ops *event_hist_get_trigger_ops(char *cmd, 6059 char *param) 6060 { 6061 return &event_hist_trigger_ops; 6062 } 6063 6064 static void hist_clear(struct event_trigger_data *data) 6065 { 6066 struct hist_trigger_data *hist_data = data->private_data; 6067 6068 if (data->name) 6069 pause_named_trigger(data); 6070 6071 tracepoint_synchronize_unregister(); 6072 6073 tracing_map_clear(hist_data->map); 6074 6075 if (data->name) 6076 unpause_named_trigger(data); 6077 } 6078 6079 static bool compatible_field(struct ftrace_event_field *field, 6080 struct ftrace_event_field *test_field) 6081 { 6082 if (field == test_field) 6083 return true; 6084 if (field == NULL || test_field == NULL) 6085 return false; 6086 if (strcmp(field->name, test_field->name) != 0) 6087 return false; 6088 if (strcmp(field->type, test_field->type) != 0) 6089 return false; 6090 if (field->size != test_field->size) 6091 return false; 6092 if (field->is_signed != test_field->is_signed) 6093 return false; 6094 6095 return true; 6096 } 6097 6098 static bool hist_trigger_match(struct event_trigger_data *data, 6099 struct event_trigger_data *data_test, 6100 struct event_trigger_data *named_data, 6101 bool ignore_filter) 6102 { 6103 struct tracing_map_sort_key *sort_key, *sort_key_test; 6104 struct hist_trigger_data *hist_data, *hist_data_test; 6105 struct hist_field *key_field, *key_field_test; 6106 unsigned int i; 6107 6108 if (named_data && (named_data != data_test) && 6109 (named_data != data_test->named_data)) 6110 return false; 6111 6112 if (!named_data && is_named_trigger(data_test)) 6113 return false; 6114 6115 hist_data = data->private_data; 6116 hist_data_test = data_test->private_data; 6117 6118 if (hist_data->n_vals != hist_data_test->n_vals || 6119 hist_data->n_fields != hist_data_test->n_fields || 6120 hist_data->n_sort_keys != hist_data_test->n_sort_keys) 6121 return false; 6122 6123 if (!ignore_filter) { 6124 if ((data->filter_str && !data_test->filter_str) || 6125 (!data->filter_str && data_test->filter_str)) 6126 return false; 6127 } 6128 6129 for_each_hist_field(i, hist_data) { 6130 key_field = hist_data->fields[i]; 6131 key_field_test = hist_data_test->fields[i]; 6132 6133 if (key_field->flags != key_field_test->flags) 6134 return false; 6135 if (!compatible_field(key_field->field, key_field_test->field)) 6136 return false; 6137 if (key_field->offset != key_field_test->offset) 6138 return false; 6139 if (key_field->size != key_field_test->size) 6140 return false; 6141 if (key_field->is_signed != key_field_test->is_signed) 6142 return false; 6143 if (!!key_field->var.name != !!key_field_test->var.name) 6144 return false; 6145 if (key_field->var.name && 6146 strcmp(key_field->var.name, key_field_test->var.name) != 0) 6147 return false; 6148 } 6149 6150 for (i = 0; i < hist_data->n_sort_keys; i++) { 6151 sort_key = &hist_data->sort_keys[i]; 6152 sort_key_test = &hist_data_test->sort_keys[i]; 6153 6154 if (sort_key->field_idx != sort_key_test->field_idx || 6155 sort_key->descending != sort_key_test->descending) 6156 return false; 6157 } 6158 6159 if (!ignore_filter && data->filter_str && 6160 (strcmp(data->filter_str, data_test->filter_str) != 0)) 6161 return false; 6162 6163 if (!actions_match(hist_data, hist_data_test)) 6164 return false; 6165 6166 return true; 6167 } 6168 6169 static bool existing_hist_update_only(char *glob, 6170 struct event_trigger_data *data, 6171 struct trace_event_file *file) 6172 { 6173 struct hist_trigger_data *hist_data = data->private_data; 6174 struct event_trigger_data *test, *named_data = NULL; 6175 bool updated = false; 6176 6177 if (!hist_data->attrs->pause && !hist_data->attrs->cont && 6178 !hist_data->attrs->clear) 6179 goto out; 6180 6181 if (hist_data->attrs->name) { 6182 named_data = find_named_trigger(hist_data->attrs->name); 6183 if (named_data) { 6184 if (!hist_trigger_match(data, named_data, named_data, 6185 true)) 6186 goto out; 6187 } 6188 } 6189 6190 if (hist_data->attrs->name && !named_data) 6191 goto out; 6192 6193 list_for_each_entry(test, &file->triggers, list) { 6194 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6195 if (!hist_trigger_match(data, test, named_data, false)) 6196 continue; 6197 if (hist_data->attrs->pause) 6198 test->paused = true; 6199 else if (hist_data->attrs->cont) 6200 test->paused = false; 6201 else if (hist_data->attrs->clear) 6202 hist_clear(test); 6203 updated = true; 6204 goto out; 6205 } 6206 } 6207 out: 6208 return updated; 6209 } 6210 6211 static int hist_register_trigger(char *glob, 6212 struct event_trigger_data *data, 6213 struct trace_event_file *file) 6214 { 6215 struct hist_trigger_data *hist_data = data->private_data; 6216 struct event_trigger_data *test, *named_data = NULL; 6217 struct trace_array *tr = file->tr; 6218 int ret = 0; 6219 6220 if (hist_data->attrs->name) { 6221 named_data = find_named_trigger(hist_data->attrs->name); 6222 if (named_data) { 6223 if (!hist_trigger_match(data, named_data, named_data, 6224 true)) { 6225 hist_err(tr, HIST_ERR_NAMED_MISMATCH, errpos(hist_data->attrs->name)); 6226 ret = -EINVAL; 6227 goto out; 6228 } 6229 } 6230 } 6231 6232 if (hist_data->attrs->name && !named_data) 6233 goto new; 6234 6235 lockdep_assert_held(&event_mutex); 6236 6237 list_for_each_entry(test, &file->triggers, list) { 6238 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6239 if (hist_trigger_match(data, test, named_data, false)) { 6240 hist_err(tr, HIST_ERR_TRIGGER_EEXIST, 0); 6241 ret = -EEXIST; 6242 goto out; 6243 } 6244 } 6245 } 6246 new: 6247 if (hist_data->attrs->cont || hist_data->attrs->clear) { 6248 hist_err(tr, HIST_ERR_TRIGGER_ENOENT_CLEAR, 0); 6249 ret = -ENOENT; 6250 goto out; 6251 } 6252 6253 if (hist_data->attrs->pause) 6254 data->paused = true; 6255 6256 if (named_data) { 6257 data->private_data = named_data->private_data; 6258 set_named_trigger_data(data, named_data); 6259 data->ops = &event_hist_trigger_named_ops; 6260 } 6261 6262 if (data->ops->init) { 6263 ret = data->ops->init(data); 6264 if (ret < 0) 6265 goto out; 6266 } 6267 6268 if (hist_data->enable_timestamps) { 6269 char *clock = hist_data->attrs->clock; 6270 6271 ret = tracing_set_clock(file->tr, hist_data->attrs->clock); 6272 if (ret) { 6273 hist_err(tr, HIST_ERR_SET_CLOCK_FAIL, errpos(clock)); 6274 goto out; 6275 } 6276 6277 tracing_set_filter_buffering(file->tr, true); 6278 } 6279 6280 if (named_data) 6281 destroy_hist_data(hist_data); 6282 out: 6283 return ret; 6284 } 6285 6286 static int hist_trigger_enable(struct event_trigger_data *data, 6287 struct trace_event_file *file) 6288 { 6289 int ret = 0; 6290 6291 list_add_tail_rcu(&data->list, &file->triggers); 6292 6293 update_cond_flag(file); 6294 6295 if (trace_event_trigger_enable_disable(file, 1) < 0) { 6296 list_del_rcu(&data->list); 6297 update_cond_flag(file); 6298 ret--; 6299 } 6300 6301 return ret; 6302 } 6303 6304 static bool have_hist_trigger_match(struct event_trigger_data *data, 6305 struct trace_event_file *file) 6306 { 6307 struct hist_trigger_data *hist_data = data->private_data; 6308 struct event_trigger_data *test, *named_data = NULL; 6309 bool match = false; 6310 6311 lockdep_assert_held(&event_mutex); 6312 6313 if (hist_data->attrs->name) 6314 named_data = find_named_trigger(hist_data->attrs->name); 6315 6316 list_for_each_entry(test, &file->triggers, list) { 6317 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6318 if (hist_trigger_match(data, test, named_data, false)) { 6319 match = true; 6320 break; 6321 } 6322 } 6323 } 6324 6325 return match; 6326 } 6327 6328 static bool hist_trigger_check_refs(struct event_trigger_data *data, 6329 struct trace_event_file *file) 6330 { 6331 struct hist_trigger_data *hist_data = data->private_data; 6332 struct event_trigger_data *test, *named_data = NULL; 6333 6334 lockdep_assert_held(&event_mutex); 6335 6336 if (hist_data->attrs->name) 6337 named_data = find_named_trigger(hist_data->attrs->name); 6338 6339 list_for_each_entry(test, &file->triggers, list) { 6340 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6341 if (!hist_trigger_match(data, test, named_data, false)) 6342 continue; 6343 hist_data = test->private_data; 6344 if (check_var_refs(hist_data)) 6345 return true; 6346 break; 6347 } 6348 } 6349 6350 return false; 6351 } 6352 6353 static void hist_unregister_trigger(char *glob, 6354 struct event_trigger_data *data, 6355 struct trace_event_file *file) 6356 { 6357 struct event_trigger_data *test = NULL, *iter, *named_data = NULL; 6358 struct hist_trigger_data *hist_data = data->private_data; 6359 6360 lockdep_assert_held(&event_mutex); 6361 6362 if (hist_data->attrs->name) 6363 named_data = find_named_trigger(hist_data->attrs->name); 6364 6365 list_for_each_entry(iter, &file->triggers, list) { 6366 if (iter->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6367 if (!hist_trigger_match(data, iter, named_data, false)) 6368 continue; 6369 test = iter; 6370 list_del_rcu(&test->list); 6371 trace_event_trigger_enable_disable(file, 0); 6372 update_cond_flag(file); 6373 break; 6374 } 6375 } 6376 6377 if (test && test->ops->free) 6378 test->ops->free(test); 6379 6380 if (hist_data->enable_timestamps) { 6381 if (!hist_data->remove || test) 6382 tracing_set_filter_buffering(file->tr, false); 6383 } 6384 } 6385 6386 static bool hist_file_check_refs(struct trace_event_file *file) 6387 { 6388 struct hist_trigger_data *hist_data; 6389 struct event_trigger_data *test; 6390 6391 lockdep_assert_held(&event_mutex); 6392 6393 list_for_each_entry(test, &file->triggers, list) { 6394 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6395 hist_data = test->private_data; 6396 if (check_var_refs(hist_data)) 6397 return true; 6398 } 6399 } 6400 6401 return false; 6402 } 6403 6404 static void hist_unreg_all(struct trace_event_file *file) 6405 { 6406 struct event_trigger_data *test, *n; 6407 struct hist_trigger_data *hist_data; 6408 struct synth_event *se; 6409 const char *se_name; 6410 6411 lockdep_assert_held(&event_mutex); 6412 6413 if (hist_file_check_refs(file)) 6414 return; 6415 6416 list_for_each_entry_safe(test, n, &file->triggers, list) { 6417 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6418 hist_data = test->private_data; 6419 list_del_rcu(&test->list); 6420 trace_event_trigger_enable_disable(file, 0); 6421 6422 se_name = trace_event_name(file->event_call); 6423 se = find_synth_event(se_name); 6424 if (se) 6425 se->ref--; 6426 6427 update_cond_flag(file); 6428 if (hist_data->enable_timestamps) 6429 tracing_set_filter_buffering(file->tr, false); 6430 if (test->ops->free) 6431 test->ops->free(test); 6432 } 6433 } 6434 } 6435 6436 static int event_hist_trigger_parse(struct event_command *cmd_ops, 6437 struct trace_event_file *file, 6438 char *glob, char *cmd, 6439 char *param_and_filter) 6440 { 6441 unsigned int hist_trigger_bits = TRACING_MAP_BITS_DEFAULT; 6442 struct event_trigger_data *trigger_data; 6443 struct hist_trigger_attrs *attrs; 6444 struct hist_trigger_data *hist_data; 6445 char *param, *filter, *p, *start; 6446 struct synth_event *se; 6447 const char *se_name; 6448 bool remove; 6449 int ret = 0; 6450 6451 lockdep_assert_held(&event_mutex); 6452 6453 if (WARN_ON(!glob)) 6454 return -EINVAL; 6455 6456 if (glob[0]) { 6457 hist_err_clear(); 6458 last_cmd_set(file, param_and_filter); 6459 } 6460 6461 remove = event_trigger_check_remove(glob); 6462 6463 if (event_trigger_empty_param(param_and_filter)) 6464 return -EINVAL; 6465 6466 /* 6467 * separate the trigger from the filter (k:v [if filter]) 6468 * allowing for whitespace in the trigger 6469 */ 6470 p = param = param_and_filter; 6471 do { 6472 p = strstr(p, "if"); 6473 if (!p) 6474 break; 6475 if (p == param_and_filter) 6476 return -EINVAL; 6477 if (*(p - 1) != ' ' && *(p - 1) != '\t') { 6478 p++; 6479 continue; 6480 } 6481 if (p >= param_and_filter + strlen(param_and_filter) - (sizeof("if") - 1) - 1) 6482 return -EINVAL; 6483 if (*(p + sizeof("if") - 1) != ' ' && *(p + sizeof("if") - 1) != '\t') { 6484 p++; 6485 continue; 6486 } 6487 break; 6488 } while (1); 6489 6490 if (!p) 6491 filter = NULL; 6492 else { 6493 *(p - 1) = '\0'; 6494 filter = strstrip(p); 6495 param = strstrip(param); 6496 } 6497 6498 /* 6499 * To simplify arithmetic expression parsing, replace occurrences of 6500 * '.sym-offset' modifier with '.symXoffset' 6501 */ 6502 start = strstr(param, ".sym-offset"); 6503 while (start) { 6504 *(start + 4) = 'X'; 6505 start = strstr(start + 11, ".sym-offset"); 6506 } 6507 6508 attrs = parse_hist_trigger_attrs(file->tr, param); 6509 if (IS_ERR(attrs)) 6510 return PTR_ERR(attrs); 6511 6512 if (attrs->map_bits) 6513 hist_trigger_bits = attrs->map_bits; 6514 6515 hist_data = create_hist_data(hist_trigger_bits, attrs, file, remove); 6516 if (IS_ERR(hist_data)) { 6517 destroy_hist_trigger_attrs(attrs); 6518 return PTR_ERR(hist_data); 6519 } 6520 6521 trigger_data = event_trigger_alloc(cmd_ops, cmd, param, hist_data); 6522 if (!trigger_data) { 6523 ret = -ENOMEM; 6524 goto out_free; 6525 } 6526 6527 ret = event_trigger_set_filter(cmd_ops, file, filter, trigger_data); 6528 if (ret < 0) 6529 goto out_free; 6530 6531 if (remove) { 6532 if (!have_hist_trigger_match(trigger_data, file)) 6533 goto out_free; 6534 6535 if (hist_trigger_check_refs(trigger_data, file)) { 6536 ret = -EBUSY; 6537 goto out_free; 6538 } 6539 6540 event_trigger_unregister(cmd_ops, file, glob+1, trigger_data); 6541 se_name = trace_event_name(file->event_call); 6542 se = find_synth_event(se_name); 6543 if (se) 6544 se->ref--; 6545 ret = 0; 6546 goto out_free; 6547 } 6548 6549 if (existing_hist_update_only(glob, trigger_data, file)) 6550 goto out_free; 6551 6552 ret = event_trigger_register(cmd_ops, file, glob, trigger_data); 6553 if (ret < 0) 6554 goto out_free; 6555 6556 if (get_named_trigger_data(trigger_data)) 6557 goto enable; 6558 6559 if (has_hist_vars(hist_data)) 6560 save_hist_vars(hist_data); 6561 6562 ret = create_actions(hist_data); 6563 if (ret) 6564 goto out_unreg; 6565 6566 ret = tracing_map_init(hist_data->map); 6567 if (ret) 6568 goto out_unreg; 6569 enable: 6570 ret = hist_trigger_enable(trigger_data, file); 6571 if (ret) 6572 goto out_unreg; 6573 6574 se_name = trace_event_name(file->event_call); 6575 se = find_synth_event(se_name); 6576 if (se) 6577 se->ref++; 6578 out: 6579 if (ret == 0 && glob[0]) 6580 hist_err_clear(); 6581 6582 return ret; 6583 out_unreg: 6584 event_trigger_unregister(cmd_ops, file, glob+1, trigger_data); 6585 out_free: 6586 event_trigger_reset_filter(cmd_ops, trigger_data); 6587 6588 remove_hist_vars(hist_data); 6589 6590 kfree(trigger_data); 6591 6592 destroy_hist_data(hist_data); 6593 goto out; 6594 } 6595 6596 static struct event_command trigger_hist_cmd = { 6597 .name = "hist", 6598 .trigger_type = ETT_EVENT_HIST, 6599 .flags = EVENT_CMD_FL_NEEDS_REC, 6600 .parse = event_hist_trigger_parse, 6601 .reg = hist_register_trigger, 6602 .unreg = hist_unregister_trigger, 6603 .unreg_all = hist_unreg_all, 6604 .get_trigger_ops = event_hist_get_trigger_ops, 6605 .set_filter = set_trigger_filter, 6606 }; 6607 6608 __init int register_trigger_hist_cmd(void) 6609 { 6610 int ret; 6611 6612 ret = register_event_command(&trigger_hist_cmd); 6613 WARN_ON(ret < 0); 6614 6615 return ret; 6616 } 6617 6618 static void 6619 hist_enable_trigger(struct event_trigger_data *data, 6620 struct trace_buffer *buffer, void *rec, 6621 struct ring_buffer_event *event) 6622 { 6623 struct enable_trigger_data *enable_data = data->private_data; 6624 struct event_trigger_data *test; 6625 6626 list_for_each_entry_rcu(test, &enable_data->file->triggers, list, 6627 lockdep_is_held(&event_mutex)) { 6628 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6629 if (enable_data->enable) 6630 test->paused = false; 6631 else 6632 test->paused = true; 6633 } 6634 } 6635 } 6636 6637 static void 6638 hist_enable_count_trigger(struct event_trigger_data *data, 6639 struct trace_buffer *buffer, void *rec, 6640 struct ring_buffer_event *event) 6641 { 6642 if (!data->count) 6643 return; 6644 6645 if (data->count != -1) 6646 (data->count)--; 6647 6648 hist_enable_trigger(data, buffer, rec, event); 6649 } 6650 6651 static struct event_trigger_ops hist_enable_trigger_ops = { 6652 .trigger = hist_enable_trigger, 6653 .print = event_enable_trigger_print, 6654 .init = event_trigger_init, 6655 .free = event_enable_trigger_free, 6656 }; 6657 6658 static struct event_trigger_ops hist_enable_count_trigger_ops = { 6659 .trigger = hist_enable_count_trigger, 6660 .print = event_enable_trigger_print, 6661 .init = event_trigger_init, 6662 .free = event_enable_trigger_free, 6663 }; 6664 6665 static struct event_trigger_ops hist_disable_trigger_ops = { 6666 .trigger = hist_enable_trigger, 6667 .print = event_enable_trigger_print, 6668 .init = event_trigger_init, 6669 .free = event_enable_trigger_free, 6670 }; 6671 6672 static struct event_trigger_ops hist_disable_count_trigger_ops = { 6673 .trigger = hist_enable_count_trigger, 6674 .print = event_enable_trigger_print, 6675 .init = event_trigger_init, 6676 .free = event_enable_trigger_free, 6677 }; 6678 6679 static struct event_trigger_ops * 6680 hist_enable_get_trigger_ops(char *cmd, char *param) 6681 { 6682 struct event_trigger_ops *ops; 6683 bool enable; 6684 6685 enable = (strcmp(cmd, ENABLE_HIST_STR) == 0); 6686 6687 if (enable) 6688 ops = param ? &hist_enable_count_trigger_ops : 6689 &hist_enable_trigger_ops; 6690 else 6691 ops = param ? &hist_disable_count_trigger_ops : 6692 &hist_disable_trigger_ops; 6693 6694 return ops; 6695 } 6696 6697 static void hist_enable_unreg_all(struct trace_event_file *file) 6698 { 6699 struct event_trigger_data *test, *n; 6700 6701 list_for_each_entry_safe(test, n, &file->triggers, list) { 6702 if (test->cmd_ops->trigger_type == ETT_HIST_ENABLE) { 6703 list_del_rcu(&test->list); 6704 update_cond_flag(file); 6705 trace_event_trigger_enable_disable(file, 0); 6706 if (test->ops->free) 6707 test->ops->free(test); 6708 } 6709 } 6710 } 6711 6712 static struct event_command trigger_hist_enable_cmd = { 6713 .name = ENABLE_HIST_STR, 6714 .trigger_type = ETT_HIST_ENABLE, 6715 .parse = event_enable_trigger_parse, 6716 .reg = event_enable_register_trigger, 6717 .unreg = event_enable_unregister_trigger, 6718 .unreg_all = hist_enable_unreg_all, 6719 .get_trigger_ops = hist_enable_get_trigger_ops, 6720 .set_filter = set_trigger_filter, 6721 }; 6722 6723 static struct event_command trigger_hist_disable_cmd = { 6724 .name = DISABLE_HIST_STR, 6725 .trigger_type = ETT_HIST_ENABLE, 6726 .parse = event_enable_trigger_parse, 6727 .reg = event_enable_register_trigger, 6728 .unreg = event_enable_unregister_trigger, 6729 .unreg_all = hist_enable_unreg_all, 6730 .get_trigger_ops = hist_enable_get_trigger_ops, 6731 .set_filter = set_trigger_filter, 6732 }; 6733 6734 static __init void unregister_trigger_hist_enable_disable_cmds(void) 6735 { 6736 unregister_event_command(&trigger_hist_enable_cmd); 6737 unregister_event_command(&trigger_hist_disable_cmd); 6738 } 6739 6740 __init int register_trigger_hist_enable_disable_cmds(void) 6741 { 6742 int ret; 6743 6744 ret = register_event_command(&trigger_hist_enable_cmd); 6745 if (WARN_ON(ret < 0)) 6746 return ret; 6747 ret = register_event_command(&trigger_hist_disable_cmd); 6748 if (WARN_ON(ret < 0)) 6749 unregister_trigger_hist_enable_disable_cmds(); 6750 6751 return ret; 6752 } 6753