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/seq_buf.h> 12 #include <linux/mutex.h> 13 #include <linux/slab.h> 14 #include <linux/stacktrace.h> 15 #include <linux/rculist.h> 16 #include <linux/tracefs.h> 17 18 /* for gfp flag names */ 19 #include <linux/trace_events.h> 20 #include <trace/events/mmflags.h> 21 22 #include "tracing_map.h" 23 #include "trace_synth.h" 24 25 #define ERRORS \ 26 C(NONE, "No error"), \ 27 C(DUPLICATE_VAR, "Variable already defined"), \ 28 C(VAR_NOT_UNIQUE, "Variable name not unique, need to use fully qualified name (subsys.event.var) for variable"), \ 29 C(TOO_MANY_VARS, "Too many variables defined"), \ 30 C(MALFORMED_ASSIGNMENT, "Malformed assignment"), \ 31 C(NAMED_MISMATCH, "Named hist trigger doesn't match existing named trigger (includes variables)"), \ 32 C(TRIGGER_EEXIST, "Hist trigger already exists"), \ 33 C(TRIGGER_ENOENT_CLEAR, "Can't clear or continue a nonexistent hist trigger"), \ 34 C(SET_CLOCK_FAIL, "Couldn't set trace_clock"), \ 35 C(BAD_FIELD_MODIFIER, "Invalid field modifier"), \ 36 C(TOO_MANY_SUBEXPR, "Too many subexpressions (3 max)"), \ 37 C(TIMESTAMP_MISMATCH, "Timestamp units in expression don't match"), \ 38 C(TOO_MANY_FIELD_VARS, "Too many field variables defined"), \ 39 C(EVENT_FILE_NOT_FOUND, "Event file not found"), \ 40 C(HIST_NOT_FOUND, "Matching event histogram not found"), \ 41 C(HIST_CREATE_FAIL, "Couldn't create histogram for field"), \ 42 C(SYNTH_VAR_NOT_FOUND, "Couldn't find synthetic variable"), \ 43 C(SYNTH_EVENT_NOT_FOUND,"Couldn't find synthetic event"), \ 44 C(SYNTH_TYPE_MISMATCH, "Param type doesn't match synthetic event field type"), \ 45 C(SYNTH_COUNT_MISMATCH, "Param count doesn't match synthetic event field count"), \ 46 C(FIELD_VAR_PARSE_FAIL, "Couldn't parse field variable"), \ 47 C(VAR_CREATE_FIND_FAIL, "Couldn't create or find variable"), \ 48 C(ONX_NOT_VAR, "For onmax(x) or onchange(x), x must be a variable"), \ 49 C(ONX_VAR_NOT_FOUND, "Couldn't find onmax or onchange variable"), \ 50 C(ONX_VAR_CREATE_FAIL, "Couldn't create onmax or onchange variable"), \ 51 C(FIELD_VAR_CREATE_FAIL,"Couldn't create field variable"), \ 52 C(TOO_MANY_PARAMS, "Too many action params"), \ 53 C(PARAM_NOT_FOUND, "Couldn't find param"), \ 54 C(INVALID_PARAM, "Invalid action param"), \ 55 C(ACTION_NOT_FOUND, "No action found"), \ 56 C(NO_SAVE_PARAMS, "No params found for save()"), \ 57 C(TOO_MANY_SAVE_ACTIONS,"Can't have more than one save() action per hist"), \ 58 C(ACTION_MISMATCH, "Handler doesn't support action"), \ 59 C(NO_CLOSING_PAREN, "No closing paren found"), \ 60 C(SUBSYS_NOT_FOUND, "Missing subsystem"), \ 61 C(INVALID_SUBSYS_EVENT, "Invalid subsystem or event name"), \ 62 C(INVALID_REF_KEY, "Using variable references in keys not supported"), \ 63 C(VAR_NOT_FOUND, "Couldn't find variable"), \ 64 C(FIELD_NOT_FOUND, "Couldn't find field"), \ 65 C(EMPTY_ASSIGNMENT, "Empty assignment"), \ 66 C(INVALID_SORT_MODIFIER,"Invalid sort modifier"), \ 67 C(EMPTY_SORT_FIELD, "Empty sort field"), \ 68 C(TOO_MANY_SORT_FIELDS, "Too many sort fields (Max = 2)"), \ 69 C(INVALID_SORT_FIELD, "Sort field must be a key or a val"), \ 70 C(INVALID_STR_OPERAND, "String type can not be an operand in expression"), \ 71 C(EXPECT_NUMBER, "Expecting numeric literal"), \ 72 C(UNARY_MINUS_SUBEXPR, "Unary minus not supported in sub-expressions"), \ 73 C(DIVISION_BY_ZERO, "Division by zero"), \ 74 C(NEED_NOHC_VAL, "Non-hitcount value is required for 'nohitcount'"), 75 76 #undef C 77 #define C(a, b) HIST_ERR_##a 78 79 enum { ERRORS }; 80 81 #undef C 82 #define C(a, b) b 83 84 static const char *err_text[] = { ERRORS }; 85 86 struct hist_field; 87 88 typedef u64 (*hist_field_fn_t) (struct hist_field *field, 89 struct tracing_map_elt *elt, 90 struct trace_buffer *buffer, 91 struct ring_buffer_event *rbe, 92 void *event); 93 94 #define HIST_FIELD_OPERANDS_MAX 2 95 #define HIST_FIELDS_MAX (TRACING_MAP_FIELDS_MAX + TRACING_MAP_VARS_MAX) 96 #define HIST_ACTIONS_MAX 8 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 #define FIELD_FUNCS \ 109 C(NOP, "nop"), \ 110 C(VAR_REF, "var_ref"), \ 111 C(COUNTER, "counter"), \ 112 C(CONST, "const"), \ 113 C(LOG2, "log2"), \ 114 C(BUCKET, "bucket"), \ 115 C(TIMESTAMP, "timestamp"), \ 116 C(CPU, "cpu"), \ 117 C(COMM, "comm"), \ 118 C(STRING, "string"), \ 119 C(DYNSTRING, "dynstring"), \ 120 C(RELDYNSTRING, "reldynstring"), \ 121 C(PSTRING, "pstring"), \ 122 C(S64, "s64"), \ 123 C(U64, "u64"), \ 124 C(S32, "s32"), \ 125 C(U32, "u32"), \ 126 C(S16, "s16"), \ 127 C(U16, "u16"), \ 128 C(S8, "s8"), \ 129 C(U8, "u8"), \ 130 C(UMINUS, "uminus"), \ 131 C(MINUS, "minus"), \ 132 C(PLUS, "plus"), \ 133 C(DIV, "div"), \ 134 C(MULT, "mult"), \ 135 C(DIV_POWER2, "div_power2"), \ 136 C(DIV_NOT_POWER2, "div_not_power2"), \ 137 C(DIV_MULT_SHIFT, "div_mult_shift"), \ 138 C(EXECNAME, "execname"), \ 139 C(STACK, "stack"), 140 141 #undef C 142 #define C(a, b) HIST_FIELD_FN_##a 143 144 enum hist_field_fn { 145 FIELD_FUNCS 146 }; 147 148 /* 149 * A hist_var (histogram variable) contains variable information for 150 * hist_fields having the HIST_FIELD_FL_VAR or HIST_FIELD_FL_VAR_REF 151 * flag set. A hist_var has a variable name e.g. ts0, and is 152 * associated with a given histogram trigger, as specified by 153 * hist_data. The hist_var idx is the unique index assigned to the 154 * variable by the hist trigger's tracing_map. The idx is what is 155 * used to set a variable's value and, by a variable reference, to 156 * retrieve it. 157 */ 158 struct hist_var { 159 char *name; 160 struct hist_trigger_data *hist_data; 161 unsigned int idx; 162 }; 163 164 struct hist_field { 165 struct ftrace_event_field *field; 166 unsigned long flags; 167 unsigned long buckets; 168 const char *type; 169 struct hist_field *operands[HIST_FIELD_OPERANDS_MAX]; 170 struct hist_trigger_data *hist_data; 171 enum hist_field_fn fn_num; 172 unsigned int ref; 173 unsigned int size; 174 unsigned int offset; 175 unsigned int is_signed; 176 177 /* 178 * Variable fields contain variable-specific info in var. 179 */ 180 struct hist_var var; 181 enum field_op_id operator; 182 char *system; 183 char *event_name; 184 185 /* 186 * The name field is used for EXPR and VAR_REF fields. VAR 187 * fields contain the variable name in var.name. 188 */ 189 char *name; 190 191 /* 192 * When a histogram trigger is hit, if it has any references 193 * to variables, the values of those variables are collected 194 * into a var_ref_vals array by resolve_var_refs(). The 195 * current value of each variable is read from the tracing_map 196 * using the hist field's hist_var.idx and entered into the 197 * var_ref_idx entry i.e. var_ref_vals[var_ref_idx]. 198 */ 199 unsigned int var_ref_idx; 200 bool read_once; 201 202 unsigned int var_str_idx; 203 204 /* Numeric literals are represented as u64 */ 205 u64 constant; 206 /* Used to optimize division by constants */ 207 u64 div_multiplier; 208 }; 209 210 static u64 hist_fn_call(struct hist_field *hist_field, 211 struct tracing_map_elt *elt, 212 struct trace_buffer *buffer, 213 struct ring_buffer_event *rbe, 214 void *event); 215 216 static u64 hist_field_const(struct hist_field *field, 217 struct tracing_map_elt *elt, 218 struct trace_buffer *buffer, 219 struct ring_buffer_event *rbe, 220 void *event) 221 { 222 return field->constant; 223 } 224 225 static u64 hist_field_counter(struct hist_field *field, 226 struct tracing_map_elt *elt, 227 struct trace_buffer *buffer, 228 struct ring_buffer_event *rbe, 229 void *event) 230 { 231 return 1; 232 } 233 234 static u64 hist_field_string(struct hist_field *hist_field, 235 struct tracing_map_elt *elt, 236 struct trace_buffer *buffer, 237 struct ring_buffer_event *rbe, 238 void *event) 239 { 240 char *addr = (char *)(event + hist_field->field->offset); 241 242 return (u64)(unsigned long)addr; 243 } 244 245 static u64 hist_field_dynstring(struct hist_field *hist_field, 246 struct tracing_map_elt *elt, 247 struct trace_buffer *buffer, 248 struct ring_buffer_event *rbe, 249 void *event) 250 { 251 u32 str_item = *(u32 *)(event + hist_field->field->offset); 252 int str_loc = str_item & 0xffff; 253 char *addr = (char *)(event + str_loc); 254 255 return (u64)(unsigned long)addr; 256 } 257 258 static u64 hist_field_reldynstring(struct hist_field *hist_field, 259 struct tracing_map_elt *elt, 260 struct trace_buffer *buffer, 261 struct ring_buffer_event *rbe, 262 void *event) 263 { 264 u32 *item = event + hist_field->field->offset; 265 u32 str_item = *item; 266 int str_loc = str_item & 0xffff; 267 char *addr = (char *)&item[1] + str_loc; 268 269 return (u64)(unsigned long)addr; 270 } 271 272 static u64 hist_field_pstring(struct hist_field *hist_field, 273 struct tracing_map_elt *elt, 274 struct trace_buffer *buffer, 275 struct ring_buffer_event *rbe, 276 void *event) 277 { 278 char **addr = (char **)(event + hist_field->field->offset); 279 280 return (u64)(unsigned long)*addr; 281 } 282 283 static u64 hist_field_log2(struct hist_field *hist_field, 284 struct tracing_map_elt *elt, 285 struct trace_buffer *buffer, 286 struct ring_buffer_event *rbe, 287 void *event) 288 { 289 struct hist_field *operand = hist_field->operands[0]; 290 291 u64 val = hist_fn_call(operand, elt, buffer, rbe, event); 292 293 return (u64) ilog2(roundup_pow_of_two(val)); 294 } 295 296 static u64 hist_field_bucket(struct hist_field *hist_field, 297 struct tracing_map_elt *elt, 298 struct trace_buffer *buffer, 299 struct ring_buffer_event *rbe, 300 void *event) 301 { 302 struct hist_field *operand = hist_field->operands[0]; 303 unsigned long buckets = hist_field->buckets; 304 305 u64 val = hist_fn_call(operand, elt, buffer, rbe, event); 306 307 if (WARN_ON_ONCE(!buckets)) 308 return val; 309 310 if (val >= LONG_MAX) 311 val = div64_ul(val, buckets); 312 else 313 val = (u64)((unsigned long)val / buckets); 314 return val * buckets; 315 } 316 317 static u64 hist_field_plus(struct hist_field *hist_field, 318 struct tracing_map_elt *elt, 319 struct trace_buffer *buffer, 320 struct ring_buffer_event *rbe, 321 void *event) 322 { 323 struct hist_field *operand1 = hist_field->operands[0]; 324 struct hist_field *operand2 = hist_field->operands[1]; 325 326 u64 val1 = hist_fn_call(operand1, elt, buffer, rbe, event); 327 u64 val2 = hist_fn_call(operand2, elt, buffer, rbe, event); 328 329 return val1 + val2; 330 } 331 332 static u64 hist_field_minus(struct hist_field *hist_field, 333 struct tracing_map_elt *elt, 334 struct trace_buffer *buffer, 335 struct ring_buffer_event *rbe, 336 void *event) 337 { 338 struct hist_field *operand1 = hist_field->operands[0]; 339 struct hist_field *operand2 = hist_field->operands[1]; 340 341 u64 val1 = hist_fn_call(operand1, elt, buffer, rbe, event); 342 u64 val2 = hist_fn_call(operand2, elt, buffer, rbe, event); 343 344 return val1 - val2; 345 } 346 347 static u64 hist_field_div(struct hist_field *hist_field, 348 struct tracing_map_elt *elt, 349 struct trace_buffer *buffer, 350 struct ring_buffer_event *rbe, 351 void *event) 352 { 353 struct hist_field *operand1 = hist_field->operands[0]; 354 struct hist_field *operand2 = hist_field->operands[1]; 355 356 u64 val1 = hist_fn_call(operand1, elt, buffer, rbe, event); 357 u64 val2 = hist_fn_call(operand2, elt, buffer, rbe, event); 358 359 /* Return -1 for the undefined case */ 360 if (!val2) 361 return -1; 362 363 /* Use shift if the divisor is a power of 2 */ 364 if (!(val2 & (val2 - 1))) 365 return val1 >> __ffs64(val2); 366 367 return div64_u64(val1, val2); 368 } 369 370 static u64 div_by_power_of_two(struct hist_field *hist_field, 371 struct tracing_map_elt *elt, 372 struct trace_buffer *buffer, 373 struct ring_buffer_event *rbe, 374 void *event) 375 { 376 struct hist_field *operand1 = hist_field->operands[0]; 377 struct hist_field *operand2 = hist_field->operands[1]; 378 379 u64 val1 = hist_fn_call(operand1, elt, buffer, rbe, event); 380 381 return val1 >> __ffs64(operand2->constant); 382 } 383 384 static u64 div_by_not_power_of_two(struct hist_field *hist_field, 385 struct tracing_map_elt *elt, 386 struct trace_buffer *buffer, 387 struct ring_buffer_event *rbe, 388 void *event) 389 { 390 struct hist_field *operand1 = hist_field->operands[0]; 391 struct hist_field *operand2 = hist_field->operands[1]; 392 393 u64 val1 = hist_fn_call(operand1, elt, buffer, rbe, event); 394 395 return div64_u64(val1, operand2->constant); 396 } 397 398 static u64 div_by_mult_and_shift(struct hist_field *hist_field, 399 struct tracing_map_elt *elt, 400 struct trace_buffer *buffer, 401 struct ring_buffer_event *rbe, 402 void *event) 403 { 404 struct hist_field *operand1 = hist_field->operands[0]; 405 struct hist_field *operand2 = hist_field->operands[1]; 406 407 u64 val1 = hist_fn_call(operand1, elt, buffer, rbe, event); 408 409 /* 410 * If the divisor is a constant, do a multiplication and shift instead. 411 * 412 * Choose Z = some power of 2. If Y <= Z, then: 413 * X / Y = (X * (Z / Y)) / Z 414 * 415 * (Z / Y) is a constant (mult) which is calculated at parse time, so: 416 * X / Y = (X * mult) / Z 417 * 418 * The division by Z can be replaced by a shift since Z is a power of 2: 419 * X / Y = (X * mult) >> HIST_DIV_SHIFT 420 * 421 * As long, as X < Z the results will not be off by more than 1. 422 */ 423 if (val1 < (1 << HIST_DIV_SHIFT)) { 424 u64 mult = operand2->div_multiplier; 425 426 return (val1 * mult + ((1 << HIST_DIV_SHIFT) - 1)) >> HIST_DIV_SHIFT; 427 } 428 429 return div64_u64(val1, operand2->constant); 430 } 431 432 static u64 hist_field_mult(struct hist_field *hist_field, 433 struct tracing_map_elt *elt, 434 struct trace_buffer *buffer, 435 struct ring_buffer_event *rbe, 436 void *event) 437 { 438 struct hist_field *operand1 = hist_field->operands[0]; 439 struct hist_field *operand2 = hist_field->operands[1]; 440 441 u64 val1 = hist_fn_call(operand1, elt, buffer, rbe, event); 442 u64 val2 = hist_fn_call(operand2, elt, buffer, rbe, event); 443 444 return val1 * val2; 445 } 446 447 static u64 hist_field_unary_minus(struct hist_field *hist_field, 448 struct tracing_map_elt *elt, 449 struct trace_buffer *buffer, 450 struct ring_buffer_event *rbe, 451 void *event) 452 { 453 struct hist_field *operand = hist_field->operands[0]; 454 455 s64 sval = (s64)hist_fn_call(operand, elt, buffer, rbe, event); 456 u64 val = (u64)-sval; 457 458 return val; 459 } 460 461 #define DEFINE_HIST_FIELD_FN(type) \ 462 static u64 hist_field_##type(struct hist_field *hist_field, \ 463 struct tracing_map_elt *elt, \ 464 struct trace_buffer *buffer, \ 465 struct ring_buffer_event *rbe, \ 466 void *event) \ 467 { \ 468 type *addr = (type *)(event + hist_field->field->offset); \ 469 \ 470 return (u64)(unsigned long)*addr; \ 471 } 472 473 DEFINE_HIST_FIELD_FN(s64); 474 DEFINE_HIST_FIELD_FN(u64); 475 DEFINE_HIST_FIELD_FN(s32); 476 DEFINE_HIST_FIELD_FN(u32); 477 DEFINE_HIST_FIELD_FN(s16); 478 DEFINE_HIST_FIELD_FN(u16); 479 DEFINE_HIST_FIELD_FN(s8); 480 DEFINE_HIST_FIELD_FN(u8); 481 482 #define for_each_hist_field(i, hist_data) \ 483 for ((i) = 0; (i) < (hist_data)->n_fields; (i)++) 484 485 #define for_each_hist_val_field(i, hist_data) \ 486 for ((i) = 0; (i) < (hist_data)->n_vals; (i)++) 487 488 #define for_each_hist_key_field(i, hist_data) \ 489 for ((i) = (hist_data)->n_vals; (i) < (hist_data)->n_fields; (i)++) 490 491 #define HITCOUNT_IDX 0 492 #define HIST_KEY_SIZE_MAX (MAX_FILTER_STR_VAL + HIST_STACKTRACE_SIZE) 493 494 enum hist_field_flags { 495 HIST_FIELD_FL_HITCOUNT = 1 << 0, 496 HIST_FIELD_FL_KEY = 1 << 1, 497 HIST_FIELD_FL_STRING = 1 << 2, 498 HIST_FIELD_FL_HEX = 1 << 3, 499 HIST_FIELD_FL_SYM = 1 << 4, 500 HIST_FIELD_FL_SYM_OFFSET = 1 << 5, 501 HIST_FIELD_FL_EXECNAME = 1 << 6, 502 HIST_FIELD_FL_SYSCALL = 1 << 7, 503 HIST_FIELD_FL_STACKTRACE = 1 << 8, 504 HIST_FIELD_FL_LOG2 = 1 << 9, 505 HIST_FIELD_FL_TIMESTAMP = 1 << 10, 506 HIST_FIELD_FL_TIMESTAMP_USECS = 1 << 11, 507 HIST_FIELD_FL_VAR = 1 << 12, 508 HIST_FIELD_FL_EXPR = 1 << 13, 509 HIST_FIELD_FL_VAR_REF = 1 << 14, 510 HIST_FIELD_FL_CPU = 1 << 15, 511 HIST_FIELD_FL_ALIAS = 1 << 16, 512 HIST_FIELD_FL_BUCKET = 1 << 17, 513 HIST_FIELD_FL_CONST = 1 << 18, 514 HIST_FIELD_FL_PERCENT = 1 << 19, 515 HIST_FIELD_FL_GRAPH = 1 << 20, 516 HIST_FIELD_FL_COMM = 1 << 21, 517 }; 518 519 struct var_defs { 520 unsigned int n_vars; 521 char *name[TRACING_MAP_VARS_MAX]; 522 char *expr[TRACING_MAP_VARS_MAX]; 523 }; 524 525 struct hist_trigger_attrs { 526 char *keys_str; 527 char *vals_str; 528 char *sort_key_str; 529 char *name; 530 char *clock; 531 bool pause; 532 bool cont; 533 bool clear; 534 bool ts_in_usecs; 535 bool no_hitcount; 536 unsigned int map_bits; 537 538 char *assignment_str[TRACING_MAP_VARS_MAX]; 539 unsigned int n_assignments; 540 541 char *action_str[HIST_ACTIONS_MAX]; 542 unsigned int n_actions; 543 544 struct var_defs var_defs; 545 }; 546 547 struct field_var { 548 struct hist_field *var; 549 struct hist_field *val; 550 }; 551 552 struct field_var_hist { 553 struct hist_trigger_data *hist_data; 554 char *cmd; 555 }; 556 557 struct hist_trigger_data { 558 struct hist_field *fields[HIST_FIELDS_MAX]; 559 unsigned int n_vals; 560 unsigned int n_keys; 561 unsigned int n_fields; 562 unsigned int n_vars; 563 unsigned int n_var_str; 564 unsigned int key_size; 565 struct tracing_map_sort_key sort_keys[TRACING_MAP_SORT_KEYS_MAX]; 566 unsigned int n_sort_keys; 567 struct trace_event_file *event_file; 568 struct hist_trigger_attrs *attrs; 569 struct tracing_map *map; 570 bool enable_timestamps; 571 bool remove; 572 struct hist_field *var_refs[TRACING_MAP_VARS_MAX]; 573 unsigned int n_var_refs; 574 575 struct action_data *actions[HIST_ACTIONS_MAX]; 576 unsigned int n_actions; 577 578 struct field_var *field_vars[SYNTH_FIELDS_MAX]; 579 unsigned int n_field_vars; 580 unsigned int n_field_var_str; 581 struct field_var_hist *field_var_hists[SYNTH_FIELDS_MAX]; 582 unsigned int n_field_var_hists; 583 584 struct field_var *save_vars[SYNTH_FIELDS_MAX]; 585 unsigned int n_save_vars; 586 unsigned int n_save_var_str; 587 }; 588 589 struct action_data; 590 591 typedef void (*action_fn_t) (struct hist_trigger_data *hist_data, 592 struct tracing_map_elt *elt, 593 struct trace_buffer *buffer, void *rec, 594 struct ring_buffer_event *rbe, void *key, 595 struct action_data *data, u64 *var_ref_vals); 596 597 typedef bool (*check_track_val_fn_t) (u64 track_val, u64 var_val); 598 599 enum handler_id { 600 HANDLER_ONMATCH = 1, 601 HANDLER_ONMAX, 602 HANDLER_ONCHANGE, 603 }; 604 605 enum action_id { 606 ACTION_SAVE = 1, 607 ACTION_TRACE, 608 ACTION_SNAPSHOT, 609 }; 610 611 struct action_data { 612 enum handler_id handler; 613 enum action_id action; 614 char *action_name; 615 action_fn_t fn; 616 617 unsigned int n_params; 618 char *params[SYNTH_FIELDS_MAX]; 619 620 /* 621 * When a histogram trigger is hit, the values of any 622 * references to variables, including variables being passed 623 * as parameters to synthetic events, are collected into a 624 * var_ref_vals array. This var_ref_idx array is an array of 625 * indices into the var_ref_vals array, one for each synthetic 626 * event param, and is passed to the synthetic event 627 * invocation. 628 */ 629 unsigned int var_ref_idx[SYNTH_FIELDS_MAX]; 630 struct synth_event *synth_event; 631 bool use_trace_keyword; 632 char *synth_event_name; 633 634 union { 635 struct { 636 char *event; 637 char *event_system; 638 } match_data; 639 640 struct { 641 /* 642 * var_str contains the $-unstripped variable 643 * name referenced by var_ref, and used when 644 * printing the action. Because var_ref 645 * creation is deferred to create_actions(), 646 * we need a per-action way to save it until 647 * then, thus var_str. 648 */ 649 char *var_str; 650 651 /* 652 * var_ref refers to the variable being 653 * tracked e.g onmax($var). 654 */ 655 struct hist_field *var_ref; 656 657 /* 658 * track_var contains the 'invisible' tracking 659 * variable created to keep the current 660 * e.g. max value. 661 */ 662 struct hist_field *track_var; 663 664 check_track_val_fn_t check_val; 665 action_fn_t save_data; 666 } track_data; 667 }; 668 }; 669 670 struct track_data { 671 u64 track_val; 672 bool updated; 673 674 unsigned int key_len; 675 void *key; 676 struct tracing_map_elt elt; 677 678 struct action_data *action_data; 679 struct hist_trigger_data *hist_data; 680 }; 681 682 struct hist_elt_data { 683 char *comm; 684 u64 *var_ref_vals; 685 int n_field_var_str; 686 char *field_var_str[] __counted_by(n_field_var_str); 687 }; 688 689 struct snapshot_context { 690 struct tracing_map_elt *elt; 691 void *key; 692 }; 693 694 /* 695 * Returns the specific division function to use if the divisor 696 * is constant. This avoids extra branches when the trigger is hit. 697 */ 698 static enum hist_field_fn hist_field_get_div_fn(struct hist_field *divisor) 699 { 700 u64 div = divisor->constant; 701 702 if (!(div & (div - 1))) 703 return HIST_FIELD_FN_DIV_POWER2; 704 705 /* If the divisor is too large, do a regular division */ 706 if (div > (1 << HIST_DIV_SHIFT)) 707 return HIST_FIELD_FN_DIV_NOT_POWER2; 708 709 divisor->div_multiplier = div64_u64((u64)(1 << HIST_DIV_SHIFT), div); 710 return HIST_FIELD_FN_DIV_MULT_SHIFT; 711 } 712 713 static void track_data_free(struct track_data *track_data) 714 { 715 struct hist_elt_data *elt_data; 716 717 if (!track_data) 718 return; 719 720 kfree(track_data->key); 721 722 elt_data = track_data->elt.private_data; 723 if (elt_data) { 724 kfree(elt_data->comm); 725 kfree(elt_data); 726 } 727 728 kfree(track_data); 729 } 730 731 static struct track_data *track_data_alloc(unsigned int key_len, 732 struct action_data *action_data, 733 struct hist_trigger_data *hist_data) 734 { 735 struct track_data *data = kzalloc_obj(*data); 736 struct hist_elt_data *elt_data; 737 738 if (!data) 739 return ERR_PTR(-ENOMEM); 740 741 data->key = kzalloc(key_len, GFP_KERNEL); 742 if (!data->key) { 743 track_data_free(data); 744 return ERR_PTR(-ENOMEM); 745 } 746 747 data->key_len = key_len; 748 data->action_data = action_data; 749 data->hist_data = hist_data; 750 751 elt_data = kzalloc_obj(*elt_data); 752 if (!elt_data) { 753 track_data_free(data); 754 return ERR_PTR(-ENOMEM); 755 } 756 757 data->elt.private_data = elt_data; 758 759 elt_data->comm = kzalloc(TASK_COMM_LEN, GFP_KERNEL); 760 if (!elt_data->comm) { 761 track_data_free(data); 762 return ERR_PTR(-ENOMEM); 763 } 764 765 return data; 766 } 767 768 #define HIST_PREFIX "hist:" 769 770 static char *last_cmd; 771 static char last_cmd_loc[MAX_FILTER_STR_VAL]; 772 773 static int errpos(char *str) 774 { 775 if (!str || !last_cmd) 776 return 0; 777 778 return err_pos(last_cmd, str); 779 } 780 781 static void last_cmd_set(struct trace_event_file *file, char *str) 782 { 783 const char *system = NULL, *name = NULL; 784 struct trace_event_call *call; 785 786 if (!str) 787 return; 788 789 kfree(last_cmd); 790 791 last_cmd = kasprintf(GFP_KERNEL, HIST_PREFIX "%s", str); 792 if (!last_cmd) 793 return; 794 795 if (file) { 796 call = file->event_call; 797 system = call->class->system; 798 if (system) { 799 name = trace_event_name(call); 800 if (!name) 801 system = NULL; 802 } 803 } 804 805 if (system) 806 snprintf(last_cmd_loc, MAX_FILTER_STR_VAL, HIST_PREFIX "%s:%s", system, name); 807 } 808 809 static void hist_err(struct trace_array *tr, u8 err_type, u16 err_pos) 810 { 811 if (!last_cmd) 812 return; 813 814 tracing_log_err(tr, last_cmd_loc, last_cmd, err_text, 815 err_type, err_pos); 816 } 817 818 static void hist_err_clear(void) 819 { 820 if (last_cmd) 821 last_cmd[0] = '\0'; 822 last_cmd_loc[0] = '\0'; 823 } 824 825 typedef void (*synth_probe_func_t) (void *__data, u64 *var_ref_vals, 826 unsigned int *var_ref_idx); 827 828 static inline void trace_synth(struct synth_event *event, u64 *var_ref_vals, 829 unsigned int *var_ref_idx) 830 { 831 struct tracepoint *tp = event->tp; 832 833 if (unlikely(static_key_enabled(&tp->key))) { 834 struct tracepoint_func *probe_func_ptr; 835 synth_probe_func_t probe_func; 836 void *__data; 837 838 if (!(cpu_online(raw_smp_processor_id()))) 839 return; 840 841 probe_func_ptr = rcu_dereference_sched((tp)->funcs); 842 if (probe_func_ptr) { 843 do { 844 probe_func = probe_func_ptr->func; 845 __data = probe_func_ptr->data; 846 probe_func(__data, var_ref_vals, var_ref_idx); 847 } while ((++probe_func_ptr)->func); 848 } 849 } 850 } 851 852 static void action_trace(struct hist_trigger_data *hist_data, 853 struct tracing_map_elt *elt, 854 struct trace_buffer *buffer, void *rec, 855 struct ring_buffer_event *rbe, void *key, 856 struct action_data *data, u64 *var_ref_vals) 857 { 858 struct synth_event *event = data->synth_event; 859 860 trace_synth(event, var_ref_vals, data->var_ref_idx); 861 } 862 863 struct hist_var_data { 864 struct list_head list; 865 struct hist_trigger_data *hist_data; 866 }; 867 868 static u64 hist_field_timestamp(struct hist_field *hist_field, 869 struct tracing_map_elt *elt, 870 struct trace_buffer *buffer, 871 struct ring_buffer_event *rbe, 872 void *event) 873 { 874 struct hist_trigger_data *hist_data = hist_field->hist_data; 875 struct trace_array *tr = hist_data->event_file->tr; 876 877 u64 ts = ring_buffer_event_time_stamp(buffer, rbe); 878 879 if (hist_data->attrs->ts_in_usecs && trace_clock_in_ns(tr)) 880 ts = ns2usecs(ts); 881 882 return ts; 883 } 884 885 static u64 hist_field_cpu(struct hist_field *hist_field, 886 struct tracing_map_elt *elt, 887 struct trace_buffer *buffer, 888 struct ring_buffer_event *rbe, 889 void *event) 890 { 891 int cpu = smp_processor_id(); 892 893 return cpu; 894 } 895 896 static u64 hist_field_comm(struct hist_field *hist_field, 897 struct tracing_map_elt *elt, 898 struct trace_buffer *buffer, 899 struct ring_buffer_event *rbe, 900 void *event) 901 { 902 return (u64)(unsigned long)current->comm; 903 } 904 905 /** 906 * check_field_for_var_ref - Check if a VAR_REF field references a variable 907 * @hist_field: The VAR_REF field to check 908 * @var_data: The hist trigger that owns the variable 909 * @var_idx: The trigger variable identifier 910 * 911 * Check the given VAR_REF field to see whether or not it references 912 * the given variable associated with the given trigger. 913 * 914 * Return: The VAR_REF field if it does reference the variable, NULL if not 915 */ 916 static struct hist_field * 917 check_field_for_var_ref(struct hist_field *hist_field, 918 struct hist_trigger_data *var_data, 919 unsigned int var_idx) 920 { 921 WARN_ON(!(hist_field && hist_field->flags & HIST_FIELD_FL_VAR_REF)); 922 923 if (hist_field && hist_field->var.idx == var_idx && 924 hist_field->var.hist_data == var_data) 925 return hist_field; 926 927 return NULL; 928 } 929 930 /** 931 * find_var_ref - Check if a trigger has a reference to a trigger variable 932 * @hist_data: The hist trigger that might have a reference to the variable 933 * @var_data: The hist trigger that owns the variable 934 * @var_idx: The trigger variable identifier 935 * 936 * Check the list of var_refs[] on the first hist trigger to see 937 * whether any of them are references to the variable on the second 938 * trigger. 939 * 940 * Return: The VAR_REF field referencing the variable if so, NULL if not 941 */ 942 static struct hist_field *find_var_ref(struct hist_trigger_data *hist_data, 943 struct hist_trigger_data *var_data, 944 unsigned int var_idx) 945 { 946 struct hist_field *hist_field; 947 unsigned int i; 948 949 for (i = 0; i < hist_data->n_var_refs; i++) { 950 hist_field = hist_data->var_refs[i]; 951 if (check_field_for_var_ref(hist_field, var_data, var_idx)) 952 return hist_field; 953 } 954 955 return NULL; 956 } 957 958 /** 959 * find_any_var_ref - Check if there is a reference to a given trigger variable 960 * @hist_data: The hist trigger 961 * @var_idx: The trigger variable identifier 962 * 963 * Check to see whether the given variable is currently referenced by 964 * any other trigger. 965 * 966 * The trigger the variable is defined on is explicitly excluded - the 967 * assumption being that a self-reference doesn't prevent a trigger 968 * from being removed. 969 * 970 * Return: The VAR_REF field referencing the variable if so, NULL if not 971 */ 972 static struct hist_field *find_any_var_ref(struct hist_trigger_data *hist_data, 973 unsigned int var_idx) 974 { 975 struct trace_array *tr = hist_data->event_file->tr; 976 struct hist_field *found = NULL; 977 struct hist_var_data *var_data; 978 979 list_for_each_entry(var_data, &tr->hist_vars, list) { 980 if (var_data->hist_data == hist_data) 981 continue; 982 found = find_var_ref(var_data->hist_data, hist_data, var_idx); 983 if (found) 984 break; 985 } 986 987 return found; 988 } 989 990 /** 991 * check_var_refs - Check if there is a reference to any of trigger's variables 992 * @hist_data: The hist trigger 993 * 994 * A trigger can define one or more variables. If any one of them is 995 * currently referenced by any other trigger, this function will 996 * determine that. 997 * 998 * Typically used to determine whether or not a trigger can be removed 999 * - if there are any references to a trigger's variables, it cannot. 1000 * 1001 * Return: True if there is a reference to any of trigger's variables 1002 */ 1003 static bool check_var_refs(struct hist_trigger_data *hist_data) 1004 { 1005 struct hist_field *field; 1006 bool found = false; 1007 int i; 1008 1009 for_each_hist_field(i, hist_data) { 1010 field = hist_data->fields[i]; 1011 if (field && field->flags & HIST_FIELD_FL_VAR) { 1012 if (find_any_var_ref(hist_data, field->var.idx)) { 1013 found = true; 1014 break; 1015 } 1016 } 1017 } 1018 1019 return found; 1020 } 1021 1022 static struct hist_var_data *find_hist_vars(struct hist_trigger_data *hist_data) 1023 { 1024 struct trace_array *tr = hist_data->event_file->tr; 1025 struct hist_var_data *var_data, *found = NULL; 1026 1027 list_for_each_entry(var_data, &tr->hist_vars, list) { 1028 if (var_data->hist_data == hist_data) { 1029 found = var_data; 1030 break; 1031 } 1032 } 1033 1034 return found; 1035 } 1036 1037 static bool field_has_hist_vars(struct hist_field *hist_field, 1038 unsigned int level) 1039 { 1040 int i; 1041 1042 if (level > 3) 1043 return false; 1044 1045 if (!hist_field) 1046 return false; 1047 1048 if (hist_field->flags & HIST_FIELD_FL_VAR || 1049 hist_field->flags & HIST_FIELD_FL_VAR_REF) 1050 return true; 1051 1052 for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++) { 1053 struct hist_field *operand; 1054 1055 operand = hist_field->operands[i]; 1056 if (field_has_hist_vars(operand, level + 1)) 1057 return true; 1058 } 1059 1060 return false; 1061 } 1062 1063 static bool has_hist_vars(struct hist_trigger_data *hist_data) 1064 { 1065 struct hist_field *hist_field; 1066 int i; 1067 1068 for_each_hist_field(i, hist_data) { 1069 hist_field = hist_data->fields[i]; 1070 if (field_has_hist_vars(hist_field, 0)) 1071 return true; 1072 } 1073 1074 return false; 1075 } 1076 1077 static int save_hist_vars(struct hist_trigger_data *hist_data) 1078 { 1079 struct trace_array *tr = hist_data->event_file->tr; 1080 struct hist_var_data *var_data; 1081 1082 var_data = find_hist_vars(hist_data); 1083 if (var_data) 1084 return 0; 1085 1086 if (tracing_check_open_get_tr(tr)) 1087 return -ENODEV; 1088 1089 var_data = kzalloc_obj(*var_data); 1090 if (!var_data) { 1091 trace_array_put(tr); 1092 return -ENOMEM; 1093 } 1094 1095 var_data->hist_data = hist_data; 1096 list_add(&var_data->list, &tr->hist_vars); 1097 1098 return 0; 1099 } 1100 1101 static void remove_hist_vars(struct hist_trigger_data *hist_data) 1102 { 1103 struct trace_array *tr = hist_data->event_file->tr; 1104 struct hist_var_data *var_data; 1105 1106 var_data = find_hist_vars(hist_data); 1107 if (!var_data) 1108 return; 1109 1110 if (WARN_ON(check_var_refs(hist_data))) 1111 return; 1112 1113 list_del(&var_data->list); 1114 1115 kfree(var_data); 1116 1117 trace_array_put(tr); 1118 } 1119 1120 static struct hist_field *find_var_field(struct hist_trigger_data *hist_data, 1121 const char *var_name) 1122 { 1123 struct hist_field *hist_field, *found = NULL; 1124 int i; 1125 1126 for_each_hist_field(i, hist_data) { 1127 hist_field = hist_data->fields[i]; 1128 if (hist_field && hist_field->flags & HIST_FIELD_FL_VAR && 1129 strcmp(hist_field->var.name, var_name) == 0) { 1130 found = hist_field; 1131 break; 1132 } 1133 } 1134 1135 return found; 1136 } 1137 1138 static struct hist_field *find_var(struct hist_trigger_data *hist_data, 1139 struct trace_event_file *file, 1140 const char *var_name) 1141 { 1142 struct hist_trigger_data *test_data; 1143 struct event_trigger_data *test; 1144 struct hist_field *hist_field; 1145 1146 lockdep_assert_held(&event_mutex); 1147 1148 hist_field = find_var_field(hist_data, var_name); 1149 if (hist_field) 1150 return hist_field; 1151 1152 list_for_each_entry(test, &file->triggers, list) { 1153 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 1154 test_data = test->private_data; 1155 hist_field = find_var_field(test_data, var_name); 1156 if (hist_field) 1157 return hist_field; 1158 } 1159 } 1160 1161 return NULL; 1162 } 1163 1164 static struct trace_event_file *find_var_file(struct trace_array *tr, 1165 char *system, 1166 char *event_name, 1167 char *var_name) 1168 { 1169 struct hist_trigger_data *var_hist_data; 1170 struct hist_var_data *var_data; 1171 struct trace_event_file *file, *found = NULL; 1172 1173 if (system) 1174 return find_event_file(tr, system, event_name); 1175 1176 list_for_each_entry(var_data, &tr->hist_vars, list) { 1177 var_hist_data = var_data->hist_data; 1178 file = var_hist_data->event_file; 1179 if (file == found) 1180 continue; 1181 1182 if (find_var_field(var_hist_data, var_name)) { 1183 if (found) { 1184 hist_err(tr, HIST_ERR_VAR_NOT_UNIQUE, errpos(var_name)); 1185 return NULL; 1186 } 1187 1188 found = file; 1189 } 1190 } 1191 1192 return found; 1193 } 1194 1195 static struct hist_field *find_file_var(struct trace_event_file *file, 1196 const char *var_name) 1197 { 1198 struct hist_trigger_data *test_data; 1199 struct event_trigger_data *test; 1200 struct hist_field *hist_field; 1201 1202 lockdep_assert_held(&event_mutex); 1203 1204 list_for_each_entry(test, &file->triggers, list) { 1205 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 1206 test_data = test->private_data; 1207 hist_field = find_var_field(test_data, var_name); 1208 if (hist_field) 1209 return hist_field; 1210 } 1211 } 1212 1213 return NULL; 1214 } 1215 1216 static struct hist_field * 1217 find_match_var(struct hist_trigger_data *hist_data, char *var_name) 1218 { 1219 struct trace_array *tr = hist_data->event_file->tr; 1220 struct hist_field *hist_field, *found = NULL; 1221 struct trace_event_file *file; 1222 unsigned int i; 1223 1224 for (i = 0; i < hist_data->n_actions; i++) { 1225 struct action_data *data = hist_data->actions[i]; 1226 1227 if (data->handler == HANDLER_ONMATCH) { 1228 char *system = data->match_data.event_system; 1229 char *event_name = data->match_data.event; 1230 1231 file = find_var_file(tr, system, event_name, var_name); 1232 if (!file) 1233 continue; 1234 hist_field = find_file_var(file, var_name); 1235 if (hist_field) { 1236 if (found) { 1237 hist_err(tr, HIST_ERR_VAR_NOT_UNIQUE, 1238 errpos(var_name)); 1239 return ERR_PTR(-EINVAL); 1240 } 1241 1242 found = hist_field; 1243 } 1244 } 1245 } 1246 return found; 1247 } 1248 1249 static struct hist_field *find_event_var(struct hist_trigger_data *hist_data, 1250 char *system, 1251 char *event_name, 1252 char *var_name) 1253 { 1254 struct trace_array *tr = hist_data->event_file->tr; 1255 struct hist_field *hist_field = NULL; 1256 struct trace_event_file *file; 1257 1258 if (!system || !event_name) { 1259 hist_field = find_match_var(hist_data, var_name); 1260 if (IS_ERR(hist_field)) 1261 return NULL; 1262 if (hist_field) 1263 return hist_field; 1264 } 1265 1266 file = find_var_file(tr, system, event_name, var_name); 1267 if (!file) 1268 return NULL; 1269 1270 hist_field = find_file_var(file, var_name); 1271 1272 return hist_field; 1273 } 1274 1275 static u64 hist_field_var_ref(struct hist_field *hist_field, 1276 struct tracing_map_elt *elt, 1277 struct trace_buffer *buffer, 1278 struct ring_buffer_event *rbe, 1279 void *event) 1280 { 1281 struct hist_elt_data *elt_data; 1282 u64 var_val = 0; 1283 1284 if (WARN_ON_ONCE(!elt)) 1285 return var_val; 1286 1287 elt_data = elt->private_data; 1288 var_val = elt_data->var_ref_vals[hist_field->var_ref_idx]; 1289 1290 return var_val; 1291 } 1292 1293 static bool resolve_var_refs(struct hist_trigger_data *hist_data, void *key, 1294 u64 *var_ref_vals, bool self) 1295 { 1296 struct hist_trigger_data *var_data; 1297 struct tracing_map_elt *var_elt; 1298 struct hist_field *hist_field; 1299 unsigned int i, var_idx; 1300 bool resolved = true; 1301 u64 var_val = 0; 1302 1303 for (i = 0; i < hist_data->n_var_refs; i++) { 1304 hist_field = hist_data->var_refs[i]; 1305 var_idx = hist_field->var.idx; 1306 var_data = hist_field->var.hist_data; 1307 1308 if (var_data == NULL) { 1309 resolved = false; 1310 break; 1311 } 1312 1313 if ((self && var_data != hist_data) || 1314 (!self && var_data == hist_data)) 1315 continue; 1316 1317 var_elt = tracing_map_lookup(var_data->map, key); 1318 if (!var_elt) { 1319 resolved = false; 1320 break; 1321 } 1322 1323 if (!tracing_map_var_set(var_elt, var_idx)) { 1324 resolved = false; 1325 break; 1326 } 1327 1328 if (self || !hist_field->read_once) 1329 var_val = tracing_map_read_var(var_elt, var_idx); 1330 else 1331 var_val = tracing_map_read_var_once(var_elt, var_idx); 1332 1333 var_ref_vals[i] = var_val; 1334 } 1335 1336 return resolved; 1337 } 1338 1339 static const char *hist_field_name(struct hist_field *field, 1340 unsigned int level) 1341 { 1342 const char *field_name = ""; 1343 1344 if (WARN_ON_ONCE(!field)) 1345 return field_name; 1346 1347 if (level > 1) 1348 return field_name; 1349 1350 if (field->field) 1351 field_name = field->field->name; 1352 else if (field->flags & HIST_FIELD_FL_LOG2 || 1353 field->flags & HIST_FIELD_FL_ALIAS || 1354 field->flags & HIST_FIELD_FL_BUCKET) 1355 field_name = hist_field_name(field->operands[0], ++level); 1356 else if (field->flags & HIST_FIELD_FL_CPU) 1357 field_name = "common_cpu"; 1358 else if (field->flags & HIST_FIELD_FL_COMM) 1359 field_name = "common_comm"; 1360 else if (field->flags & HIST_FIELD_FL_EXPR || 1361 field->flags & HIST_FIELD_FL_VAR_REF) { 1362 if (field->system) { 1363 static char full_name[MAX_FILTER_STR_VAL]; 1364 static char *fmt; 1365 int len; 1366 1367 fmt = field->flags & HIST_FIELD_FL_VAR_REF ? "%s.%s.$%s" : "%s.%s.%s"; 1368 1369 len = snprintf(full_name, sizeof(full_name), fmt, 1370 field->system, field->event_name, 1371 field->name); 1372 if (len < sizeof(full_name)) 1373 field_name = full_name; 1374 } else 1375 field_name = field->name; 1376 } else if (field->flags & HIST_FIELD_FL_TIMESTAMP) 1377 field_name = "common_timestamp"; 1378 else if (field->flags & HIST_FIELD_FL_STACKTRACE) { 1379 field_name = "common_stacktrace"; 1380 } else if (field->flags & HIST_FIELD_FL_HITCOUNT) 1381 field_name = "hitcount"; 1382 1383 if (field_name == NULL) 1384 field_name = ""; 1385 1386 return field_name; 1387 } 1388 1389 static enum hist_field_fn select_value_fn(int field_size, int field_is_signed) 1390 { 1391 switch (field_size) { 1392 case 8: 1393 if (field_is_signed) 1394 return HIST_FIELD_FN_S64; 1395 else 1396 return HIST_FIELD_FN_U64; 1397 case 4: 1398 if (field_is_signed) 1399 return HIST_FIELD_FN_S32; 1400 else 1401 return HIST_FIELD_FN_U32; 1402 case 2: 1403 if (field_is_signed) 1404 return HIST_FIELD_FN_S16; 1405 else 1406 return HIST_FIELD_FN_U16; 1407 case 1: 1408 if (field_is_signed) 1409 return HIST_FIELD_FN_S8; 1410 else 1411 return HIST_FIELD_FN_U8; 1412 } 1413 1414 return HIST_FIELD_FN_NOP; 1415 } 1416 1417 static int parse_map_size(char *str) 1418 { 1419 unsigned long size, map_bits; 1420 int ret; 1421 1422 ret = kstrtoul(str, 0, &size); 1423 if (ret) 1424 goto out; 1425 1426 map_bits = ilog2(roundup_pow_of_two(size)); 1427 if (map_bits < TRACING_MAP_BITS_MIN || 1428 map_bits > TRACING_MAP_BITS_MAX) 1429 ret = -EINVAL; 1430 else 1431 ret = map_bits; 1432 out: 1433 return ret; 1434 } 1435 1436 static void destroy_hist_trigger_attrs(struct hist_trigger_attrs *attrs) 1437 { 1438 unsigned int i; 1439 1440 if (!attrs) 1441 return; 1442 1443 for (i = 0; i < attrs->n_assignments; i++) 1444 kfree(attrs->assignment_str[i]); 1445 1446 for (i = 0; i < attrs->n_actions; i++) 1447 kfree(attrs->action_str[i]); 1448 1449 kfree(attrs->name); 1450 kfree(attrs->sort_key_str); 1451 kfree(attrs->keys_str); 1452 kfree(attrs->vals_str); 1453 kfree(attrs->clock); 1454 kfree(attrs); 1455 } 1456 1457 static int parse_action(char *str, struct hist_trigger_attrs *attrs) 1458 { 1459 int ret = -EINVAL; 1460 1461 if (attrs->n_actions >= HIST_ACTIONS_MAX) 1462 return ret; 1463 1464 if ((str_has_prefix(str, "onmatch(")) || 1465 (str_has_prefix(str, "onmax(")) || 1466 (str_has_prefix(str, "onchange("))) { 1467 attrs->action_str[attrs->n_actions] = kstrdup(str, GFP_KERNEL); 1468 if (!attrs->action_str[attrs->n_actions]) { 1469 ret = -ENOMEM; 1470 return ret; 1471 } 1472 attrs->n_actions++; 1473 ret = 0; 1474 } 1475 return ret; 1476 } 1477 1478 static int parse_assignment(struct trace_array *tr, 1479 char *str, struct hist_trigger_attrs *attrs) 1480 { 1481 int len, ret = 0; 1482 1483 if ((len = str_has_prefix(str, "key=")) || 1484 (len = str_has_prefix(str, "keys="))) { 1485 attrs->keys_str = kstrdup(str + len, GFP_KERNEL); 1486 if (!attrs->keys_str) { 1487 ret = -ENOMEM; 1488 goto out; 1489 } 1490 } else if ((len = str_has_prefix(str, "val=")) || 1491 (len = str_has_prefix(str, "vals=")) || 1492 (len = str_has_prefix(str, "values="))) { 1493 attrs->vals_str = kstrdup(str + len, GFP_KERNEL); 1494 if (!attrs->vals_str) { 1495 ret = -ENOMEM; 1496 goto out; 1497 } 1498 } else if ((len = str_has_prefix(str, "sort="))) { 1499 attrs->sort_key_str = kstrdup(str + len, GFP_KERNEL); 1500 if (!attrs->sort_key_str) { 1501 ret = -ENOMEM; 1502 goto out; 1503 } 1504 } else if (str_has_prefix(str, "name=")) { 1505 attrs->name = kstrdup(str, GFP_KERNEL); 1506 if (!attrs->name) { 1507 ret = -ENOMEM; 1508 goto out; 1509 } 1510 } else if ((len = str_has_prefix(str, "clock="))) { 1511 str += len; 1512 1513 str = strstrip(str); 1514 attrs->clock = kstrdup(str, GFP_KERNEL); 1515 if (!attrs->clock) { 1516 ret = -ENOMEM; 1517 goto out; 1518 } 1519 } else if ((len = str_has_prefix(str, "size="))) { 1520 int map_bits = parse_map_size(str + len); 1521 1522 if (map_bits < 0) { 1523 ret = map_bits; 1524 goto out; 1525 } 1526 attrs->map_bits = map_bits; 1527 } else { 1528 char *assignment; 1529 1530 if (attrs->n_assignments == TRACING_MAP_VARS_MAX) { 1531 hist_err(tr, HIST_ERR_TOO_MANY_VARS, errpos(str)); 1532 ret = -EINVAL; 1533 goto out; 1534 } 1535 1536 assignment = kstrdup(str, GFP_KERNEL); 1537 if (!assignment) { 1538 ret = -ENOMEM; 1539 goto out; 1540 } 1541 1542 attrs->assignment_str[attrs->n_assignments++] = assignment; 1543 } 1544 out: 1545 return ret; 1546 } 1547 1548 static struct hist_trigger_attrs * 1549 parse_hist_trigger_attrs(struct trace_array *tr, char *trigger_str) 1550 { 1551 struct hist_trigger_attrs *attrs; 1552 int ret = 0; 1553 1554 attrs = kzalloc_obj(*attrs); 1555 if (!attrs) 1556 return ERR_PTR(-ENOMEM); 1557 1558 while (trigger_str) { 1559 char *str = strsep(&trigger_str, ":"); 1560 char *rhs; 1561 1562 rhs = strchr(str, '='); 1563 if (rhs) { 1564 if (!strlen(++rhs)) { 1565 ret = -EINVAL; 1566 hist_err(tr, HIST_ERR_EMPTY_ASSIGNMENT, errpos(str)); 1567 goto free; 1568 } 1569 ret = parse_assignment(tr, str, attrs); 1570 if (ret) 1571 goto free; 1572 } else if (strcmp(str, "nohitcount") == 0 || 1573 strcmp(str, "NOHC") == 0) 1574 attrs->no_hitcount = true; 1575 else if (strcmp(str, "pause") == 0) 1576 attrs->pause = true; 1577 else if ((strcmp(str, "cont") == 0) || 1578 (strcmp(str, "continue") == 0)) 1579 attrs->cont = true; 1580 else if (strcmp(str, "clear") == 0) 1581 attrs->clear = true; 1582 else { 1583 ret = parse_action(str, attrs); 1584 if (ret) 1585 goto free; 1586 } 1587 } 1588 1589 if (!attrs->keys_str) { 1590 ret = -EINVAL; 1591 goto free; 1592 } 1593 1594 if (!attrs->clock) { 1595 attrs->clock = kstrdup("global", GFP_KERNEL); 1596 if (!attrs->clock) { 1597 ret = -ENOMEM; 1598 goto free; 1599 } 1600 } 1601 1602 return attrs; 1603 free: 1604 destroy_hist_trigger_attrs(attrs); 1605 1606 return ERR_PTR(ret); 1607 } 1608 1609 static inline void save_comm(char *comm, struct task_struct *task) 1610 { 1611 if (!task->pid) { 1612 strcpy(comm, "<idle>"); 1613 return; 1614 } 1615 1616 if (WARN_ON_ONCE(task->pid < 0)) { 1617 strcpy(comm, "<XXX>"); 1618 return; 1619 } 1620 1621 strscpy(comm, task->comm, TASK_COMM_LEN); 1622 } 1623 1624 static void hist_elt_data_free(struct hist_elt_data *elt_data) 1625 { 1626 unsigned int i; 1627 1628 for (i = 0; i < elt_data->n_field_var_str; i++) 1629 kfree(elt_data->field_var_str[i]); 1630 1631 kfree(elt_data->comm); 1632 kfree(elt_data); 1633 } 1634 1635 static void hist_trigger_elt_data_free(struct tracing_map_elt *elt) 1636 { 1637 struct hist_elt_data *elt_data = elt->private_data; 1638 1639 hist_elt_data_free(elt_data); 1640 } 1641 1642 static int hist_trigger_elt_data_alloc(struct tracing_map_elt *elt) 1643 { 1644 struct hist_trigger_data *hist_data = elt->map->private_data; 1645 unsigned int size = TASK_COMM_LEN; 1646 struct hist_elt_data *elt_data; 1647 struct hist_field *hist_field; 1648 unsigned int i, n_str; 1649 1650 BUILD_BUG_ON(STR_VAR_LEN_MAX & (sizeof(u64) - 1)); 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 return -EINVAL; 1656 1657 elt_data = kzalloc_flex(*elt_data, field_var_str, n_str); 1658 if (!elt_data) 1659 return -ENOMEM; 1660 1661 elt_data->n_field_var_str = n_str; 1662 1663 for_each_hist_field(i, hist_data) { 1664 hist_field = hist_data->fields[i]; 1665 1666 if (hist_field->flags & HIST_FIELD_FL_EXECNAME) { 1667 elt_data->comm = kzalloc(size, GFP_KERNEL); 1668 if (!elt_data->comm) { 1669 kfree(elt_data); 1670 return -ENOMEM; 1671 } 1672 break; 1673 } 1674 } 1675 1676 size = STR_VAR_LEN_MAX; 1677 1678 for (i = 0; i < n_str; i++) { 1679 elt_data->field_var_str[i] = kzalloc(size, GFP_KERNEL); 1680 if (!elt_data->field_var_str[i]) { 1681 hist_elt_data_free(elt_data); 1682 return -ENOMEM; 1683 } 1684 } 1685 1686 elt->private_data = elt_data; 1687 1688 return 0; 1689 } 1690 1691 static void hist_trigger_elt_data_init(struct tracing_map_elt *elt) 1692 { 1693 struct hist_elt_data *elt_data = elt->private_data; 1694 1695 if (elt_data->comm) 1696 save_comm(elt_data->comm, current); 1697 } 1698 1699 static const struct tracing_map_ops hist_trigger_elt_data_ops = { 1700 .elt_alloc = hist_trigger_elt_data_alloc, 1701 .elt_free = hist_trigger_elt_data_free, 1702 .elt_init = hist_trigger_elt_data_init, 1703 }; 1704 1705 static const char *get_hist_field_flags(struct hist_field *hist_field) 1706 { 1707 const char *flags_str = NULL; 1708 1709 if (hist_field->flags & HIST_FIELD_FL_HEX) 1710 flags_str = "hex"; 1711 else if (hist_field->flags & HIST_FIELD_FL_SYM) 1712 flags_str = "sym"; 1713 else if (hist_field->flags & HIST_FIELD_FL_SYM_OFFSET) 1714 flags_str = "sym-offset"; 1715 else if (hist_field->flags & HIST_FIELD_FL_EXECNAME) 1716 flags_str = "execname"; 1717 else if (hist_field->flags & HIST_FIELD_FL_SYSCALL) 1718 flags_str = "syscall"; 1719 else if (hist_field->flags & HIST_FIELD_FL_LOG2) 1720 flags_str = "log2"; 1721 else if (hist_field->flags & HIST_FIELD_FL_BUCKET) 1722 flags_str = "buckets"; 1723 else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP_USECS) 1724 flags_str = "usecs"; 1725 else if (hist_field->flags & HIST_FIELD_FL_PERCENT) 1726 flags_str = "percent"; 1727 else if (hist_field->flags & HIST_FIELD_FL_GRAPH) 1728 flags_str = "graph"; 1729 else if (hist_field->flags & HIST_FIELD_FL_STACKTRACE) 1730 flags_str = "stacktrace"; 1731 1732 return flags_str; 1733 } 1734 1735 static bool expr_field_str(struct hist_field *field, struct seq_buf *s) 1736 { 1737 const char *field_name; 1738 1739 if (field->flags & HIST_FIELD_FL_VAR_REF) { 1740 if (!field->system) 1741 seq_buf_putc(s, '$'); 1742 } else if (field->flags & HIST_FIELD_FL_CONST) 1743 seq_buf_printf(s, "%llu", field->constant); 1744 1745 field_name = hist_field_name(field, 0); 1746 if (!field_name) 1747 return false; 1748 1749 seq_buf_puts(s, field_name); 1750 1751 if (field->flags && !(field->flags & HIST_FIELD_FL_VAR_REF)) { 1752 const char *flags_str = get_hist_field_flags(field); 1753 1754 if (flags_str) 1755 seq_buf_printf(s, ".%s", flags_str); 1756 } 1757 1758 return !seq_buf_has_overflowed(s); 1759 } 1760 1761 static char *expr_str(struct hist_field *field, unsigned int level) 1762 { 1763 char *expr __free(kfree) = NULL; 1764 struct seq_buf s; 1765 1766 if (level > 1) 1767 return ERR_PTR(-EINVAL); 1768 1769 expr = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL); 1770 if (!expr) 1771 return ERR_PTR(-ENOMEM); 1772 1773 seq_buf_init(&s, expr, MAX_FILTER_STR_VAL); 1774 1775 if (!field->operands[0]) { 1776 if (!expr_field_str(field, &s)) 1777 return ERR_PTR(-E2BIG); 1778 1779 return_ptr(expr); 1780 } 1781 1782 if (field->operator == FIELD_OP_UNARY_MINUS) { 1783 char *subexpr; 1784 1785 subexpr = expr_str(field->operands[0], ++level); 1786 if (IS_ERR(subexpr)) 1787 return subexpr; 1788 1789 seq_buf_printf(&s, "-(%s)", subexpr); 1790 kfree(subexpr); 1791 1792 if (seq_buf_has_overflowed(&s)) 1793 return ERR_PTR(-E2BIG); 1794 1795 return_ptr(expr); 1796 } 1797 1798 if (!expr_field_str(field->operands[0], &s)) 1799 return ERR_PTR(-E2BIG); 1800 1801 switch (field->operator) { 1802 case FIELD_OP_MINUS: 1803 seq_buf_putc(&s, '-'); 1804 break; 1805 case FIELD_OP_PLUS: 1806 seq_buf_putc(&s, '+'); 1807 break; 1808 case FIELD_OP_DIV: 1809 seq_buf_putc(&s, '/'); 1810 break; 1811 case FIELD_OP_MULT: 1812 seq_buf_putc(&s, '*'); 1813 break; 1814 default: 1815 return ERR_PTR(-EINVAL); 1816 } 1817 1818 if (seq_buf_has_overflowed(&s) || 1819 !expr_field_str(field->operands[1], &s)) 1820 return ERR_PTR(-E2BIG); 1821 1822 return_ptr(expr); 1823 } 1824 1825 /* 1826 * If field_op != FIELD_OP_NONE, *sep points to the root operator 1827 * of the expression tree to be evaluated. 1828 */ 1829 static int contains_operator(char *str, char **sep) 1830 { 1831 enum field_op_id field_op = FIELD_OP_NONE; 1832 char *minus_op, *plus_op, *div_op, *mult_op; 1833 1834 1835 /* 1836 * Report the last occurrence of the operators first, so that the 1837 * expression is evaluated left to right. This is important since 1838 * subtraction and division are not associative. 1839 * 1840 * e.g 1841 * 64/8/4/2 is 1, i.e 64/8/4/2 = ((64/8)/4)/2 1842 * 14-7-5-2 is 0, i.e 14-7-5-2 = ((14-7)-5)-2 1843 */ 1844 1845 /* 1846 * First, find lower precedence addition and subtraction 1847 * since the expression will be evaluated recursively. 1848 */ 1849 minus_op = strrchr(str, '-'); 1850 if (minus_op) { 1851 /* 1852 * Unary minus is not supported in sub-expressions. If 1853 * present, it is always the next root operator. 1854 */ 1855 if (minus_op == str) { 1856 field_op = FIELD_OP_UNARY_MINUS; 1857 goto out; 1858 } 1859 1860 field_op = FIELD_OP_MINUS; 1861 } 1862 1863 plus_op = strrchr(str, '+'); 1864 if (plus_op || minus_op) { 1865 /* 1866 * For operators of the same precedence use to rightmost as the 1867 * root, so that the expression is evaluated left to right. 1868 */ 1869 if (plus_op > minus_op) 1870 field_op = FIELD_OP_PLUS; 1871 goto out; 1872 } 1873 1874 /* 1875 * Multiplication and division have higher precedence than addition and 1876 * subtraction. 1877 */ 1878 div_op = strrchr(str, '/'); 1879 if (div_op) 1880 field_op = FIELD_OP_DIV; 1881 1882 mult_op = strrchr(str, '*'); 1883 /* 1884 * For operators of the same precedence use to rightmost as the 1885 * root, so that the expression is evaluated left to right. 1886 */ 1887 if (mult_op > div_op) 1888 field_op = FIELD_OP_MULT; 1889 1890 out: 1891 if (sep) { 1892 switch (field_op) { 1893 case FIELD_OP_UNARY_MINUS: 1894 case FIELD_OP_MINUS: 1895 *sep = minus_op; 1896 break; 1897 case FIELD_OP_PLUS: 1898 *sep = plus_op; 1899 break; 1900 case FIELD_OP_DIV: 1901 *sep = div_op; 1902 break; 1903 case FIELD_OP_MULT: 1904 *sep = mult_op; 1905 break; 1906 case FIELD_OP_NONE: 1907 default: 1908 *sep = NULL; 1909 break; 1910 } 1911 } 1912 1913 return field_op; 1914 } 1915 1916 static void get_hist_field(struct hist_field *hist_field) 1917 { 1918 hist_field->ref++; 1919 } 1920 1921 static void __destroy_hist_field(struct hist_field *hist_field) 1922 { 1923 if (--hist_field->ref > 1) 1924 return; 1925 1926 kfree(hist_field->var.name); 1927 kfree(hist_field->name); 1928 1929 /* Can likely be a const */ 1930 kfree_const(hist_field->type); 1931 1932 kfree(hist_field->system); 1933 kfree(hist_field->event_name); 1934 1935 kfree(hist_field); 1936 } 1937 1938 static void destroy_hist_field(struct hist_field *hist_field, 1939 unsigned int level) 1940 { 1941 unsigned int i; 1942 1943 if (level > 3) 1944 return; 1945 1946 if (!hist_field) 1947 return; 1948 1949 if (hist_field->flags & HIST_FIELD_FL_VAR_REF) 1950 return; /* var refs will be destroyed separately */ 1951 1952 for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++) 1953 destroy_hist_field(hist_field->operands[i], level + 1); 1954 1955 __destroy_hist_field(hist_field); 1956 } 1957 1958 static struct hist_field *create_hist_field(struct hist_trigger_data *hist_data, 1959 struct ftrace_event_field *field, 1960 unsigned long flags, 1961 char *var_name) 1962 { 1963 struct hist_field *hist_field; 1964 1965 if (field && is_function_field(field)) 1966 return NULL; 1967 1968 hist_field = kzalloc_obj(struct hist_field); 1969 if (!hist_field) 1970 return NULL; 1971 1972 hist_field->ref = 1; 1973 1974 hist_field->hist_data = hist_data; 1975 1976 if (flags & HIST_FIELD_FL_EXPR || flags & HIST_FIELD_FL_ALIAS) 1977 goto out; /* caller will populate */ 1978 1979 if (flags & HIST_FIELD_FL_VAR_REF) { 1980 hist_field->fn_num = HIST_FIELD_FN_VAR_REF; 1981 goto out; 1982 } 1983 1984 if (flags & HIST_FIELD_FL_HITCOUNT) { 1985 hist_field->fn_num = HIST_FIELD_FN_COUNTER; 1986 hist_field->size = sizeof(u64); 1987 hist_field->type = "u64"; 1988 goto out; 1989 } 1990 1991 if (flags & HIST_FIELD_FL_CONST) { 1992 hist_field->fn_num = HIST_FIELD_FN_CONST; 1993 hist_field->size = sizeof(u64); 1994 hist_field->type = "u64"; 1995 goto out; 1996 } 1997 1998 if (flags & HIST_FIELD_FL_STACKTRACE) { 1999 if (field) 2000 hist_field->fn_num = HIST_FIELD_FN_STACK; 2001 else 2002 hist_field->fn_num = HIST_FIELD_FN_NOP; 2003 hist_field->size = HIST_STACKTRACE_SIZE; 2004 hist_field->type = kstrdup_const("unsigned long[]", GFP_KERNEL); 2005 if (!hist_field->type) 2006 goto free; 2007 goto out; 2008 } 2009 2010 if (flags & (HIST_FIELD_FL_LOG2 | HIST_FIELD_FL_BUCKET)) { 2011 unsigned long fl = flags & ~(HIST_FIELD_FL_LOG2 | HIST_FIELD_FL_BUCKET); 2012 hist_field->fn_num = flags & HIST_FIELD_FL_LOG2 ? HIST_FIELD_FN_LOG2 : 2013 HIST_FIELD_FN_BUCKET; 2014 hist_field->operands[0] = create_hist_field(hist_data, field, fl, NULL); 2015 if (!hist_field->operands[0]) 2016 goto free; 2017 hist_field->size = hist_field->operands[0]->size; 2018 hist_field->type = kstrdup_const(hist_field->operands[0]->type, GFP_KERNEL); 2019 if (!hist_field->type) 2020 goto free; 2021 goto out; 2022 } 2023 2024 if (flags & HIST_FIELD_FL_TIMESTAMP) { 2025 hist_field->fn_num = HIST_FIELD_FN_TIMESTAMP; 2026 hist_field->size = sizeof(u64); 2027 hist_field->type = "u64"; 2028 goto out; 2029 } 2030 2031 if (flags & HIST_FIELD_FL_CPU) { 2032 hist_field->fn_num = HIST_FIELD_FN_CPU; 2033 hist_field->size = sizeof(int); 2034 hist_field->type = "unsigned int"; 2035 goto out; 2036 } 2037 2038 if (flags & HIST_FIELD_FL_COMM) { 2039 hist_field->fn_num = HIST_FIELD_FN_COMM; 2040 hist_field->size = MAX_FILTER_STR_VAL; 2041 hist_field->type = "char[]"; 2042 goto out; 2043 } 2044 2045 if (WARN_ON_ONCE(!field)) 2046 goto out; 2047 2048 /* Pointers to strings are just pointers and dangerous to dereference */ 2049 if (is_string_field(field) && 2050 (field->filter_type != FILTER_PTR_STRING)) { 2051 flags |= HIST_FIELD_FL_STRING; 2052 2053 hist_field->size = MAX_FILTER_STR_VAL; 2054 hist_field->type = kstrdup_const(field->type, GFP_KERNEL); 2055 if (!hist_field->type) 2056 goto free; 2057 2058 if (field->filter_type == FILTER_STATIC_STRING) { 2059 hist_field->fn_num = HIST_FIELD_FN_STRING; 2060 hist_field->size = field->size; 2061 } else if (field->filter_type == FILTER_DYN_STRING) { 2062 hist_field->fn_num = HIST_FIELD_FN_DYNSTRING; 2063 } else if (field->filter_type == FILTER_RDYN_STRING) 2064 hist_field->fn_num = HIST_FIELD_FN_RELDYNSTRING; 2065 else 2066 hist_field->fn_num = HIST_FIELD_FN_PSTRING; 2067 } else if (field->filter_type == FILTER_STACKTRACE) { 2068 flags |= HIST_FIELD_FL_STACKTRACE; 2069 2070 hist_field->size = MAX_FILTER_STR_VAL; 2071 hist_field->type = kstrdup_const(field->type, GFP_KERNEL); 2072 if (!hist_field->type) 2073 goto free; 2074 2075 hist_field->fn_num = HIST_FIELD_FN_STACK; 2076 } else { 2077 hist_field->size = field->size; 2078 hist_field->is_signed = field->is_signed; 2079 hist_field->type = kstrdup_const(field->type, GFP_KERNEL); 2080 if (!hist_field->type) 2081 goto free; 2082 2083 hist_field->fn_num = select_value_fn(field->size, 2084 field->is_signed); 2085 if (hist_field->fn_num == HIST_FIELD_FN_NOP) { 2086 destroy_hist_field(hist_field, 0); 2087 return NULL; 2088 } 2089 } 2090 out: 2091 hist_field->field = field; 2092 hist_field->flags = flags; 2093 2094 if (var_name) { 2095 hist_field->var.name = kstrdup(var_name, GFP_KERNEL); 2096 if (!hist_field->var.name) 2097 goto free; 2098 } 2099 2100 return hist_field; 2101 free: 2102 destroy_hist_field(hist_field, 0); 2103 return NULL; 2104 } 2105 2106 static void destroy_hist_fields(struct hist_trigger_data *hist_data) 2107 { 2108 unsigned int i; 2109 2110 for (i = 0; i < HIST_FIELDS_MAX; i++) { 2111 if (hist_data->fields[i]) { 2112 destroy_hist_field(hist_data->fields[i], 0); 2113 hist_data->fields[i] = NULL; 2114 } 2115 } 2116 2117 for (i = 0; i < hist_data->n_var_refs; i++) { 2118 WARN_ON(!(hist_data->var_refs[i]->flags & HIST_FIELD_FL_VAR_REF)); 2119 __destroy_hist_field(hist_data->var_refs[i]); 2120 hist_data->var_refs[i] = NULL; 2121 } 2122 } 2123 2124 static int init_var_ref(struct hist_field *ref_field, 2125 struct hist_field *var_field, 2126 char *system, char *event_name) 2127 { 2128 int err = 0; 2129 2130 ref_field->var.idx = var_field->var.idx; 2131 ref_field->var.hist_data = var_field->hist_data; 2132 ref_field->size = var_field->size; 2133 ref_field->is_signed = var_field->is_signed; 2134 ref_field->flags |= var_field->flags & 2135 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS); 2136 2137 if (system) { 2138 ref_field->system = kstrdup(system, GFP_KERNEL); 2139 if (!ref_field->system) 2140 return -ENOMEM; 2141 } 2142 2143 if (event_name) { 2144 ref_field->event_name = kstrdup(event_name, GFP_KERNEL); 2145 if (!ref_field->event_name) { 2146 err = -ENOMEM; 2147 goto free; 2148 } 2149 } 2150 2151 if (var_field->var.name) { 2152 ref_field->name = kstrdup(var_field->var.name, GFP_KERNEL); 2153 if (!ref_field->name) { 2154 err = -ENOMEM; 2155 goto free; 2156 } 2157 } else if (var_field->name) { 2158 ref_field->name = kstrdup(var_field->name, GFP_KERNEL); 2159 if (!ref_field->name) { 2160 err = -ENOMEM; 2161 goto free; 2162 } 2163 } 2164 2165 ref_field->type = kstrdup_const(var_field->type, GFP_KERNEL); 2166 if (!ref_field->type) { 2167 err = -ENOMEM; 2168 goto free; 2169 } 2170 out: 2171 return err; 2172 free: 2173 kfree(ref_field->system); 2174 ref_field->system = NULL; 2175 kfree(ref_field->event_name); 2176 ref_field->event_name = NULL; 2177 kfree(ref_field->name); 2178 ref_field->name = NULL; 2179 2180 goto out; 2181 } 2182 2183 static int find_var_ref_idx(struct hist_trigger_data *hist_data, 2184 struct hist_field *var_field) 2185 { 2186 struct hist_field *ref_field; 2187 int i; 2188 2189 for (i = 0; i < hist_data->n_var_refs; i++) { 2190 ref_field = hist_data->var_refs[i]; 2191 if (ref_field->var.idx == var_field->var.idx && 2192 ref_field->var.hist_data == var_field->hist_data) 2193 return i; 2194 } 2195 2196 return -ENOENT; 2197 } 2198 2199 /** 2200 * create_var_ref - Create a variable reference and attach it to trigger 2201 * @hist_data: The trigger that will be referencing the variable 2202 * @var_field: The VAR field to create a reference to 2203 * @system: The optional system string 2204 * @event_name: The optional event_name string 2205 * 2206 * Given a variable hist_field, create a VAR_REF hist_field that 2207 * represents a reference to it. 2208 * 2209 * This function also adds the reference to the trigger that 2210 * now references the variable. 2211 * 2212 * Return: The VAR_REF field if successful, NULL if not 2213 */ 2214 static struct hist_field *create_var_ref(struct hist_trigger_data *hist_data, 2215 struct hist_field *var_field, 2216 char *system, char *event_name) 2217 { 2218 unsigned long flags = HIST_FIELD_FL_VAR_REF; 2219 struct hist_field *ref_field; 2220 int i; 2221 2222 /* Check if the variable already exists */ 2223 for (i = 0; i < hist_data->n_var_refs; i++) { 2224 ref_field = hist_data->var_refs[i]; 2225 if (ref_field->var.idx == var_field->var.idx && 2226 ref_field->var.hist_data == var_field->hist_data) { 2227 get_hist_field(ref_field); 2228 return ref_field; 2229 } 2230 } 2231 /* Sanity check to avoid out-of-bound write on 'hist_data->var_refs' */ 2232 if (hist_data->n_var_refs >= TRACING_MAP_VARS_MAX) 2233 return NULL; 2234 ref_field = create_hist_field(var_field->hist_data, NULL, flags, NULL); 2235 if (ref_field) { 2236 if (init_var_ref(ref_field, var_field, system, event_name)) { 2237 destroy_hist_field(ref_field, 0); 2238 return NULL; 2239 } 2240 2241 hist_data->var_refs[hist_data->n_var_refs] = ref_field; 2242 ref_field->var_ref_idx = hist_data->n_var_refs++; 2243 } 2244 2245 return ref_field; 2246 } 2247 2248 static bool is_var_ref(char *var_name) 2249 { 2250 if (!var_name || strlen(var_name) < 2 || var_name[0] != '$') 2251 return false; 2252 2253 return true; 2254 } 2255 2256 static char *field_name_from_var(struct hist_trigger_data *hist_data, 2257 char *var_name) 2258 { 2259 char *name, *field; 2260 unsigned int i; 2261 2262 for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) { 2263 name = hist_data->attrs->var_defs.name[i]; 2264 2265 if (strcmp(var_name, name) == 0) { 2266 field = hist_data->attrs->var_defs.expr[i]; 2267 if (contains_operator(field, NULL) || is_var_ref(field)) 2268 continue; 2269 return field; 2270 } 2271 } 2272 2273 return NULL; 2274 } 2275 2276 static char *local_field_var_ref(struct hist_trigger_data *hist_data, 2277 char *system, char *event_name, 2278 char *var_name) 2279 { 2280 struct trace_event_call *call; 2281 2282 if (system && event_name) { 2283 call = hist_data->event_file->event_call; 2284 2285 if (strcmp(system, call->class->system) != 0) 2286 return NULL; 2287 2288 if (strcmp(event_name, trace_event_name(call)) != 0) 2289 return NULL; 2290 } 2291 2292 if (!!system != !!event_name) 2293 return NULL; 2294 2295 if (!is_var_ref(var_name)) 2296 return NULL; 2297 2298 var_name++; 2299 2300 return field_name_from_var(hist_data, var_name); 2301 } 2302 2303 static struct hist_field *parse_var_ref(struct hist_trigger_data *hist_data, 2304 char *system, char *event_name, 2305 char *var_name) 2306 { 2307 struct hist_field *var_field = NULL, *ref_field = NULL; 2308 struct trace_array *tr = hist_data->event_file->tr; 2309 2310 if (!is_var_ref(var_name)) 2311 return NULL; 2312 2313 var_name++; 2314 2315 var_field = find_event_var(hist_data, system, event_name, var_name); 2316 if (var_field) 2317 ref_field = create_var_ref(hist_data, var_field, 2318 system, event_name); 2319 2320 if (!ref_field) 2321 hist_err(tr, HIST_ERR_VAR_NOT_FOUND, errpos(var_name)); 2322 2323 return ref_field; 2324 } 2325 2326 static struct ftrace_event_field * 2327 parse_field(struct hist_trigger_data *hist_data, struct trace_event_file *file, 2328 char *field_str, unsigned long *flags, unsigned long *buckets) 2329 { 2330 struct ftrace_event_field *field = NULL; 2331 char *field_name, *modifier, *str; 2332 struct trace_array *tr = file->tr; 2333 2334 modifier = str = kstrdup(field_str, GFP_KERNEL); 2335 if (!modifier) 2336 return ERR_PTR(-ENOMEM); 2337 2338 field_name = strsep(&modifier, "."); 2339 if (modifier) { 2340 if (strcmp(modifier, "hex") == 0) 2341 *flags |= HIST_FIELD_FL_HEX; 2342 else if (strcmp(modifier, "sym") == 0) 2343 *flags |= HIST_FIELD_FL_SYM; 2344 /* 2345 * 'sym-offset' occurrences in the trigger string are modified 2346 * to 'symXoffset' to simplify arithmetic expression parsing. 2347 */ 2348 else if (strcmp(modifier, "symXoffset") == 0) 2349 *flags |= HIST_FIELD_FL_SYM_OFFSET; 2350 else if ((strcmp(modifier, "execname") == 0) && 2351 (strcmp(field_name, "common_pid") == 0)) 2352 *flags |= HIST_FIELD_FL_EXECNAME; 2353 else if (strcmp(modifier, "syscall") == 0) 2354 *flags |= HIST_FIELD_FL_SYSCALL; 2355 else if (strcmp(modifier, "stacktrace") == 0) 2356 *flags |= HIST_FIELD_FL_STACKTRACE; 2357 else if (strcmp(modifier, "log2") == 0) 2358 *flags |= HIST_FIELD_FL_LOG2; 2359 else if (strcmp(modifier, "usecs") == 0) 2360 *flags |= HIST_FIELD_FL_TIMESTAMP_USECS; 2361 else if (strncmp(modifier, "bucket", 6) == 0) { 2362 int ret; 2363 2364 modifier += 6; 2365 2366 if (*modifier == 's') 2367 modifier++; 2368 if (*modifier != '=') 2369 goto error; 2370 modifier++; 2371 ret = kstrtoul(modifier, 0, buckets); 2372 if (ret || !(*buckets)) 2373 goto error; 2374 *flags |= HIST_FIELD_FL_BUCKET; 2375 } else if (strncmp(modifier, "percent", 7) == 0) { 2376 if (*flags & (HIST_FIELD_FL_VAR | HIST_FIELD_FL_KEY)) 2377 goto error; 2378 *flags |= HIST_FIELD_FL_PERCENT; 2379 } else if (strncmp(modifier, "graph", 5) == 0) { 2380 if (*flags & (HIST_FIELD_FL_VAR | HIST_FIELD_FL_KEY)) 2381 goto error; 2382 *flags |= HIST_FIELD_FL_GRAPH; 2383 } else { 2384 error: 2385 hist_err(tr, HIST_ERR_BAD_FIELD_MODIFIER, errpos(modifier)); 2386 field = ERR_PTR(-EINVAL); 2387 goto out; 2388 } 2389 } 2390 2391 if (strcmp(field_name, "common_timestamp") == 0) { 2392 *flags |= HIST_FIELD_FL_TIMESTAMP; 2393 hist_data->enable_timestamps = true; 2394 if (*flags & HIST_FIELD_FL_TIMESTAMP_USECS) 2395 hist_data->attrs->ts_in_usecs = true; 2396 } else if (strcmp(field_name, "common_stacktrace") == 0) { 2397 *flags |= HIST_FIELD_FL_STACKTRACE; 2398 } else if (strcmp(field_name, "common_cpu") == 0) { 2399 *flags |= HIST_FIELD_FL_CPU; 2400 } else if (strcmp(field_name, "common_comm") == 0) { 2401 *flags |= HIST_FIELD_FL_COMM | HIST_FIELD_FL_STRING; 2402 } else if (strcmp(field_name, "hitcount") == 0) 2403 *flags |= HIST_FIELD_FL_HITCOUNT; 2404 else { 2405 field = trace_find_event_field(file->event_call, field_name); 2406 if (!field || !field->size) { 2407 /* 2408 * For backward compatibility, if field_name 2409 * was "cpu" or "stacktrace", then we treat this 2410 * the same as common_cpu and common_stacktrace 2411 * respectively. This also works for "CPU", and 2412 * "STACKTRACE". 2413 */ 2414 if (field && field->filter_type == FILTER_CPU) { 2415 *flags |= HIST_FIELD_FL_CPU; 2416 } else if (field && field->filter_type == FILTER_STACKTRACE) { 2417 *flags |= HIST_FIELD_FL_STACKTRACE; 2418 } else if (field && field->filter_type == FILTER_COMM) { 2419 *flags |= HIST_FIELD_FL_COMM | HIST_FIELD_FL_STRING; 2420 } else { 2421 hist_err(tr, HIST_ERR_FIELD_NOT_FOUND, 2422 errpos(field_name)); 2423 field = ERR_PTR(-EINVAL); 2424 goto out; 2425 } 2426 } 2427 } 2428 out: 2429 kfree(str); 2430 2431 return field; 2432 } 2433 2434 static struct hist_field *create_alias(struct hist_trigger_data *hist_data, 2435 struct hist_field *var_ref, 2436 char *var_name) 2437 { 2438 struct hist_field *alias = NULL; 2439 unsigned long flags = HIST_FIELD_FL_ALIAS | HIST_FIELD_FL_VAR; 2440 2441 alias = create_hist_field(hist_data, NULL, flags, var_name); 2442 if (!alias) 2443 return NULL; 2444 2445 alias->fn_num = var_ref->fn_num; 2446 alias->operands[0] = var_ref; 2447 2448 if (init_var_ref(alias, var_ref, var_ref->system, var_ref->event_name)) { 2449 destroy_hist_field(alias, 0); 2450 return NULL; 2451 } 2452 2453 alias->var_ref_idx = var_ref->var_ref_idx; 2454 2455 return alias; 2456 } 2457 2458 static struct hist_field *parse_const(struct hist_trigger_data *hist_data, 2459 char *str, char *var_name, 2460 unsigned long *flags) 2461 { 2462 struct trace_array *tr = hist_data->event_file->tr; 2463 struct hist_field *field = NULL; 2464 u64 constant; 2465 2466 if (kstrtoull(str, 0, &constant)) { 2467 hist_err(tr, HIST_ERR_EXPECT_NUMBER, errpos(str)); 2468 return NULL; 2469 } 2470 2471 *flags |= HIST_FIELD_FL_CONST; 2472 field = create_hist_field(hist_data, NULL, *flags, var_name); 2473 if (!field) 2474 return NULL; 2475 2476 field->constant = constant; 2477 2478 return field; 2479 } 2480 2481 static struct hist_field *parse_atom(struct hist_trigger_data *hist_data, 2482 struct trace_event_file *file, char *str, 2483 unsigned long *flags, char *var_name) 2484 { 2485 char *s, *ref_system = NULL, *ref_event = NULL, *ref_var = str; 2486 struct ftrace_event_field *field = NULL; 2487 struct hist_field *hist_field = NULL; 2488 unsigned long buckets = 0; 2489 int ret = 0; 2490 2491 if (isdigit(str[0])) { 2492 hist_field = parse_const(hist_data, str, var_name, flags); 2493 if (!hist_field) { 2494 ret = -EINVAL; 2495 goto out; 2496 } 2497 return hist_field; 2498 } 2499 2500 s = strchr(str, '.'); 2501 if (s) { 2502 s = strchr(++s, '.'); 2503 if (s) { 2504 ref_system = strsep(&str, "."); 2505 if (!str) { 2506 ret = -EINVAL; 2507 goto out; 2508 } 2509 ref_event = strsep(&str, "."); 2510 if (!str) { 2511 ret = -EINVAL; 2512 goto out; 2513 } 2514 ref_var = str; 2515 } 2516 } 2517 2518 s = local_field_var_ref(hist_data, ref_system, ref_event, ref_var); 2519 if (!s) { 2520 hist_field = parse_var_ref(hist_data, ref_system, 2521 ref_event, ref_var); 2522 if (hist_field) { 2523 if (var_name) { 2524 hist_field = create_alias(hist_data, hist_field, var_name); 2525 if (!hist_field) { 2526 ret = -ENOMEM; 2527 goto out; 2528 } 2529 } 2530 return hist_field; 2531 } 2532 } else 2533 str = s; 2534 2535 field = parse_field(hist_data, file, str, flags, &buckets); 2536 if (IS_ERR(field)) { 2537 ret = PTR_ERR(field); 2538 goto out; 2539 } 2540 2541 hist_field = create_hist_field(hist_data, field, *flags, var_name); 2542 if (!hist_field) { 2543 ret = -ENOMEM; 2544 goto out; 2545 } 2546 hist_field->buckets = buckets; 2547 2548 return hist_field; 2549 out: 2550 return ERR_PTR(ret); 2551 } 2552 2553 static struct hist_field *parse_expr(struct hist_trigger_data *hist_data, 2554 struct trace_event_file *file, 2555 char *str, unsigned long flags, 2556 char *var_name, unsigned int *n_subexprs); 2557 2558 static struct hist_field *parse_unary(struct hist_trigger_data *hist_data, 2559 struct trace_event_file *file, 2560 char *str, unsigned long flags, 2561 char *var_name, unsigned int *n_subexprs) 2562 { 2563 struct hist_field *operand1, *expr = NULL; 2564 unsigned long operand_flags; 2565 int ret = 0; 2566 char *s; 2567 2568 /* Unary minus operator, increment n_subexprs */ 2569 ++*n_subexprs; 2570 2571 /* we support only -(xxx) i.e. explicit parens required */ 2572 2573 if (*n_subexprs > 3) { 2574 hist_err(file->tr, HIST_ERR_TOO_MANY_SUBEXPR, errpos(str)); 2575 ret = -EINVAL; 2576 goto free; 2577 } 2578 2579 str++; /* skip leading '-' */ 2580 2581 s = strchr(str, '('); 2582 if (s) 2583 str++; 2584 else { 2585 ret = -EINVAL; 2586 goto free; 2587 } 2588 2589 s = strrchr(str, ')'); 2590 if (s) { 2591 /* unary minus not supported in sub-expressions */ 2592 if (*(s+1) != '\0') { 2593 hist_err(file->tr, HIST_ERR_UNARY_MINUS_SUBEXPR, 2594 errpos(str)); 2595 ret = -EINVAL; 2596 goto free; 2597 } 2598 *s = '\0'; 2599 } 2600 else { 2601 ret = -EINVAL; /* no closing ')' */ 2602 goto free; 2603 } 2604 2605 flags |= HIST_FIELD_FL_EXPR; 2606 expr = create_hist_field(hist_data, NULL, flags, var_name); 2607 if (!expr) { 2608 ret = -ENOMEM; 2609 goto free; 2610 } 2611 2612 operand_flags = 0; 2613 operand1 = parse_expr(hist_data, file, str, operand_flags, NULL, n_subexprs); 2614 if (IS_ERR(operand1)) { 2615 ret = PTR_ERR(operand1); 2616 goto free; 2617 } 2618 if (operand1->flags & HIST_FIELD_FL_STRING) { 2619 /* String type can not be the operand of unary operator. */ 2620 hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(str)); 2621 destroy_hist_field(operand1, 0); 2622 ret = -EINVAL; 2623 goto free; 2624 } 2625 2626 expr->flags |= operand1->flags & 2627 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS); 2628 expr->fn_num = HIST_FIELD_FN_UMINUS; 2629 expr->operands[0] = operand1; 2630 expr->size = operand1->size; 2631 expr->is_signed = operand1->is_signed; 2632 expr->operator = FIELD_OP_UNARY_MINUS; 2633 expr->name = expr_str(expr, 0); 2634 if (IS_ERR(expr->name)) { 2635 ret = PTR_ERR(expr->name); 2636 expr->name = NULL; 2637 goto free; 2638 } 2639 expr->type = kstrdup_const(operand1->type, GFP_KERNEL); 2640 if (!expr->type) { 2641 ret = -ENOMEM; 2642 goto free; 2643 } 2644 2645 return expr; 2646 free: 2647 destroy_hist_field(expr, 0); 2648 return ERR_PTR(ret); 2649 } 2650 2651 /* 2652 * If the operands are var refs, return pointers the 2653 * variable(s) referenced in var1 and var2, else NULL. 2654 */ 2655 static int check_expr_operands(struct trace_array *tr, 2656 struct hist_field *operand1, 2657 struct hist_field *operand2, 2658 struct hist_field **var1, 2659 struct hist_field **var2) 2660 { 2661 unsigned long operand1_flags = operand1->flags; 2662 unsigned long operand2_flags = operand2->flags; 2663 2664 if ((operand1_flags & HIST_FIELD_FL_VAR_REF) || 2665 (operand1_flags & HIST_FIELD_FL_ALIAS)) { 2666 struct hist_field *var; 2667 2668 var = find_var_field(operand1->var.hist_data, operand1->name); 2669 if (!var) 2670 return -EINVAL; 2671 operand1_flags = var->flags; 2672 *var1 = var; 2673 } 2674 2675 if ((operand2_flags & HIST_FIELD_FL_VAR_REF) || 2676 (operand2_flags & HIST_FIELD_FL_ALIAS)) { 2677 struct hist_field *var; 2678 2679 var = find_var_field(operand2->var.hist_data, operand2->name); 2680 if (!var) 2681 return -EINVAL; 2682 operand2_flags = var->flags; 2683 *var2 = var; 2684 } 2685 2686 if ((operand1_flags & HIST_FIELD_FL_TIMESTAMP_USECS) != 2687 (operand2_flags & HIST_FIELD_FL_TIMESTAMP_USECS)) { 2688 hist_err(tr, HIST_ERR_TIMESTAMP_MISMATCH, 0); 2689 return -EINVAL; 2690 } 2691 2692 return 0; 2693 } 2694 2695 static struct hist_field *parse_expr(struct hist_trigger_data *hist_data, 2696 struct trace_event_file *file, 2697 char *str, unsigned long flags, 2698 char *var_name, unsigned int *n_subexprs) 2699 { 2700 struct hist_field *operand1 = NULL, *operand2 = NULL, *expr = NULL; 2701 struct hist_field *var1 = NULL, *var2 = NULL; 2702 unsigned long operand_flags, operand2_flags; 2703 int field_op, ret = -EINVAL; 2704 char *sep, *operand1_str; 2705 enum hist_field_fn op_fn; 2706 bool combine_consts; 2707 2708 if (*n_subexprs > 3) { 2709 hist_err(file->tr, HIST_ERR_TOO_MANY_SUBEXPR, errpos(str)); 2710 return ERR_PTR(-EINVAL); 2711 } 2712 2713 field_op = contains_operator(str, &sep); 2714 2715 if (field_op == FIELD_OP_NONE) 2716 return parse_atom(hist_data, file, str, &flags, var_name); 2717 2718 if (field_op == FIELD_OP_UNARY_MINUS) 2719 return parse_unary(hist_data, file, str, flags, var_name, n_subexprs); 2720 2721 /* Binary operator found, increment n_subexprs */ 2722 ++*n_subexprs; 2723 2724 /* Split the expression string at the root operator */ 2725 if (!sep) 2726 return ERR_PTR(-EINVAL); 2727 2728 *sep = '\0'; 2729 operand1_str = str; 2730 str = sep+1; 2731 2732 /* Binary operator requires both operands */ 2733 if (*operand1_str == '\0' || *str == '\0') 2734 return ERR_PTR(-EINVAL); 2735 2736 operand_flags = 0; 2737 2738 /* LHS of string is an expression e.g. a+b in a+b+c */ 2739 operand1 = parse_expr(hist_data, file, operand1_str, operand_flags, NULL, n_subexprs); 2740 if (IS_ERR(operand1)) 2741 return ERR_CAST(operand1); 2742 2743 if (operand1->flags & HIST_FIELD_FL_STRING) { 2744 hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(operand1_str)); 2745 ret = -EINVAL; 2746 goto free_op1; 2747 } 2748 2749 /* RHS of string is another expression e.g. c in a+b+c */ 2750 operand_flags = 0; 2751 operand2 = parse_expr(hist_data, file, str, operand_flags, NULL, n_subexprs); 2752 if (IS_ERR(operand2)) { 2753 ret = PTR_ERR(operand2); 2754 goto free_op1; 2755 } 2756 if (operand2->flags & HIST_FIELD_FL_STRING) { 2757 hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(str)); 2758 ret = -EINVAL; 2759 goto free_operands; 2760 } 2761 2762 switch (field_op) { 2763 case FIELD_OP_MINUS: 2764 op_fn = HIST_FIELD_FN_MINUS; 2765 break; 2766 case FIELD_OP_PLUS: 2767 op_fn = HIST_FIELD_FN_PLUS; 2768 break; 2769 case FIELD_OP_DIV: 2770 op_fn = HIST_FIELD_FN_DIV; 2771 break; 2772 case FIELD_OP_MULT: 2773 op_fn = HIST_FIELD_FN_MULT; 2774 break; 2775 default: 2776 ret = -EINVAL; 2777 goto free_operands; 2778 } 2779 2780 ret = check_expr_operands(file->tr, operand1, operand2, &var1, &var2); 2781 if (ret) 2782 goto free_operands; 2783 2784 operand_flags = var1 ? var1->flags : operand1->flags; 2785 operand2_flags = var2 ? var2->flags : operand2->flags; 2786 2787 /* 2788 * If both operands are constant, the expression can be 2789 * collapsed to a single constant. 2790 */ 2791 combine_consts = operand_flags & operand2_flags & HIST_FIELD_FL_CONST; 2792 2793 flags |= combine_consts ? HIST_FIELD_FL_CONST : HIST_FIELD_FL_EXPR; 2794 2795 flags |= operand1->flags & 2796 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS); 2797 2798 expr = create_hist_field(hist_data, NULL, flags, var_name); 2799 if (!expr) { 2800 ret = -ENOMEM; 2801 goto free_operands; 2802 } 2803 2804 operand1->read_once = true; 2805 operand2->read_once = true; 2806 2807 /* The operands are now owned and free'd by 'expr' */ 2808 expr->operands[0] = operand1; 2809 expr->operands[1] = operand2; 2810 2811 if (field_op == FIELD_OP_DIV && 2812 operand2_flags & HIST_FIELD_FL_CONST) { 2813 u64 divisor = var2 ? var2->constant : operand2->constant; 2814 2815 if (!divisor) { 2816 hist_err(file->tr, HIST_ERR_DIVISION_BY_ZERO, errpos(str)); 2817 ret = -EDOM; 2818 goto free_expr; 2819 } 2820 2821 /* 2822 * Copy the divisor here so we don't have to look it up 2823 * later if this is a var ref 2824 */ 2825 operand2->constant = divisor; 2826 op_fn = hist_field_get_div_fn(operand2); 2827 } 2828 2829 expr->fn_num = op_fn; 2830 2831 if (combine_consts) { 2832 if (var1) 2833 expr->operands[0] = var1; 2834 if (var2) 2835 expr->operands[1] = var2; 2836 2837 expr->constant = hist_fn_call(expr, NULL, NULL, NULL, NULL); 2838 expr->fn_num = HIST_FIELD_FN_CONST; 2839 2840 expr->operands[0] = NULL; 2841 expr->operands[1] = NULL; 2842 2843 /* 2844 * var refs won't be destroyed immediately 2845 * See: destroy_hist_field() 2846 */ 2847 destroy_hist_field(operand2, 0); 2848 destroy_hist_field(operand1, 0); 2849 2850 expr->name = expr_str(expr, 0); 2851 if (IS_ERR(expr->name)) { 2852 ret = PTR_ERR(expr->name); 2853 expr->name = NULL; 2854 goto free_expr; 2855 } 2856 } else { 2857 /* The operand sizes should be the same, so just pick one */ 2858 expr->size = operand1->size; 2859 expr->is_signed = operand1->is_signed; 2860 2861 expr->operator = field_op; 2862 expr->type = kstrdup_const(operand1->type, GFP_KERNEL); 2863 if (!expr->type) { 2864 ret = -ENOMEM; 2865 goto free_expr; 2866 } 2867 2868 expr->name = expr_str(expr, 0); 2869 if (IS_ERR(expr->name)) { 2870 ret = PTR_ERR(expr->name); 2871 expr->name = NULL; 2872 goto free_expr; 2873 } 2874 } 2875 2876 return expr; 2877 2878 free_operands: 2879 destroy_hist_field(operand2, 0); 2880 free_op1: 2881 destroy_hist_field(operand1, 0); 2882 return ERR_PTR(ret); 2883 2884 free_expr: 2885 destroy_hist_field(expr, 0); 2886 return ERR_PTR(ret); 2887 } 2888 2889 static char *find_trigger_filter(struct hist_trigger_data *hist_data, 2890 struct trace_event_file *file) 2891 { 2892 struct event_trigger_data *test; 2893 2894 lockdep_assert_held(&event_mutex); 2895 2896 list_for_each_entry(test, &file->triggers, list) { 2897 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 2898 if (test->private_data == hist_data) 2899 return test->filter_str; 2900 } 2901 } 2902 2903 return NULL; 2904 } 2905 2906 static struct event_command trigger_hist_cmd; 2907 static int event_hist_trigger_parse(struct event_command *cmd_ops, 2908 struct trace_event_file *file, 2909 char *glob, char *cmd, 2910 char *param_and_filter); 2911 2912 static bool compatible_keys(struct hist_trigger_data *target_hist_data, 2913 struct hist_trigger_data *hist_data, 2914 unsigned int n_keys) 2915 { 2916 struct hist_field *target_hist_field, *hist_field; 2917 unsigned int n, i, j; 2918 2919 if (hist_data->n_fields - hist_data->n_vals != n_keys) 2920 return false; 2921 2922 i = hist_data->n_vals; 2923 j = target_hist_data->n_vals; 2924 2925 for (n = 0; n < n_keys; n++) { 2926 hist_field = hist_data->fields[i + n]; 2927 target_hist_field = target_hist_data->fields[j + n]; 2928 2929 if (strcmp(hist_field->type, target_hist_field->type) != 0) 2930 return false; 2931 if (hist_field->size != target_hist_field->size) 2932 return false; 2933 if (hist_field->is_signed != target_hist_field->is_signed) 2934 return false; 2935 } 2936 2937 return true; 2938 } 2939 2940 static struct hist_trigger_data * 2941 find_compatible_hist(struct hist_trigger_data *target_hist_data, 2942 struct trace_event_file *file) 2943 { 2944 struct hist_trigger_data *hist_data; 2945 struct event_trigger_data *test; 2946 unsigned int n_keys; 2947 2948 lockdep_assert_held(&event_mutex); 2949 2950 n_keys = target_hist_data->n_fields - target_hist_data->n_vals; 2951 2952 list_for_each_entry(test, &file->triggers, list) { 2953 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 2954 hist_data = test->private_data; 2955 2956 if (compatible_keys(target_hist_data, hist_data, n_keys)) 2957 return hist_data; 2958 } 2959 } 2960 2961 return NULL; 2962 } 2963 2964 static struct trace_event_file *event_file(struct trace_array *tr, 2965 char *system, char *event_name) 2966 { 2967 struct trace_event_file *file; 2968 2969 file = __find_event_file(tr, system, event_name); 2970 if (!file) 2971 return ERR_PTR(-EINVAL); 2972 2973 return file; 2974 } 2975 2976 static struct hist_field * 2977 find_synthetic_field_var(struct hist_trigger_data *target_hist_data, 2978 char *system, char *event_name, char *field_name) 2979 { 2980 struct hist_field *event_var; 2981 char *synthetic_name; 2982 struct seq_buf s; 2983 2984 synthetic_name = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL); 2985 if (!synthetic_name) 2986 return ERR_PTR(-ENOMEM); 2987 2988 seq_buf_init(&s, synthetic_name, MAX_FILTER_STR_VAL); 2989 seq_buf_printf(&s, "synthetic_%s", field_name); 2990 2991 /* Terminate synthetic_name with a NUL. */ 2992 seq_buf_str(&s); 2993 2994 if (seq_buf_has_overflowed(&s)) { 2995 kfree(synthetic_name); 2996 return ERR_PTR(-E2BIG); 2997 } 2998 2999 event_var = find_event_var(target_hist_data, system, event_name, synthetic_name); 3000 3001 kfree(synthetic_name); 3002 3003 return event_var; 3004 } 3005 3006 /** 3007 * create_field_var_hist - Automatically create a histogram and var for a field 3008 * @target_hist_data: The target hist trigger 3009 * @subsys_name: Optional subsystem name 3010 * @event_name: Optional event name 3011 * @field_name: The name of the field (and the resulting variable) 3012 * 3013 * Hist trigger actions fetch data from variables, not directly from 3014 * events. However, for convenience, users are allowed to directly 3015 * specify an event field in an action, which will be automatically 3016 * converted into a variable on their behalf. 3017 * 3018 * If a user specifies a field on an event that isn't the event the 3019 * histogram currently being defined (the target event histogram), the 3020 * only way that can be accomplished is if a new hist trigger is 3021 * created and the field variable defined on that. 3022 * 3023 * This function creates a new histogram compatible with the target 3024 * event (meaning a histogram with the same key as the target 3025 * histogram), and creates a variable for the specified field, but 3026 * with 'synthetic_' prepended to the variable name in order to avoid 3027 * collision with normal field variables. 3028 * 3029 * Return: The variable created for the field. 3030 */ 3031 static struct hist_field * 3032 create_field_var_hist(struct hist_trigger_data *target_hist_data, 3033 char *subsys_name, char *event_name, char *field_name) 3034 { 3035 struct trace_array *tr = target_hist_data->event_file->tr; 3036 struct hist_trigger_data *hist_data; 3037 unsigned int i, n, first = true; 3038 struct field_var_hist *var_hist; 3039 struct trace_event_file *file; 3040 struct hist_field *key_field; 3041 struct hist_field *event_var; 3042 char *saved_filter; 3043 struct seq_buf s; 3044 char *cmd; 3045 int ret; 3046 3047 if (target_hist_data->n_field_var_hists >= SYNTH_FIELDS_MAX) { 3048 hist_err(tr, HIST_ERR_TOO_MANY_FIELD_VARS, errpos(field_name)); 3049 return ERR_PTR(-EINVAL); 3050 } 3051 3052 file = event_file(tr, subsys_name, event_name); 3053 3054 if (IS_ERR(file)) { 3055 hist_err(tr, HIST_ERR_EVENT_FILE_NOT_FOUND, errpos(field_name)); 3056 ret = PTR_ERR(file); 3057 return ERR_PTR(ret); 3058 } 3059 3060 /* 3061 * Look for a histogram compatible with target. We'll use the 3062 * found histogram specification to create a new matching 3063 * histogram with our variable on it. target_hist_data is not 3064 * yet a registered histogram so we can't use that. 3065 */ 3066 hist_data = find_compatible_hist(target_hist_data, file); 3067 if (!hist_data) { 3068 hist_err(tr, HIST_ERR_HIST_NOT_FOUND, errpos(field_name)); 3069 return ERR_PTR(-EINVAL); 3070 } 3071 3072 /* See if a synthetic field variable has already been created */ 3073 event_var = find_synthetic_field_var(target_hist_data, subsys_name, 3074 event_name, field_name); 3075 if (!IS_ERR_OR_NULL(event_var)) 3076 return event_var; 3077 3078 var_hist = kzalloc_obj(*var_hist); 3079 if (!var_hist) 3080 return ERR_PTR(-ENOMEM); 3081 3082 cmd = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL); 3083 if (!cmd) { 3084 kfree(var_hist); 3085 return ERR_PTR(-ENOMEM); 3086 } 3087 3088 seq_buf_init(&s, cmd, MAX_FILTER_STR_VAL); 3089 3090 /* Use the same keys as the compatible histogram */ 3091 seq_buf_puts(&s, "keys="); 3092 3093 for_each_hist_key_field(i, hist_data) { 3094 key_field = hist_data->fields[i]; 3095 if (!first) 3096 seq_buf_putc(&s, ','); 3097 seq_buf_puts(&s, key_field->field->name); 3098 first = false; 3099 } 3100 3101 /* Create the synthetic field variable specification */ 3102 seq_buf_printf(&s, ":synthetic_%s=%s", field_name, field_name); 3103 3104 /* Use the same filter as the compatible histogram */ 3105 saved_filter = find_trigger_filter(hist_data, file); 3106 if (saved_filter) 3107 seq_buf_printf(&s, " if %s", saved_filter); 3108 3109 /* Terminate cmd with a NUL. */ 3110 seq_buf_str(&s); 3111 3112 if (seq_buf_has_overflowed(&s)) { 3113 kfree(cmd); 3114 kfree(var_hist); 3115 return ERR_PTR(-E2BIG); 3116 } 3117 3118 var_hist->cmd = kstrdup(cmd, GFP_KERNEL); 3119 if (!var_hist->cmd) { 3120 kfree(cmd); 3121 kfree(var_hist); 3122 return ERR_PTR(-ENOMEM); 3123 } 3124 3125 /* Save the compatible histogram information */ 3126 var_hist->hist_data = hist_data; 3127 3128 /* Create the new histogram with our variable */ 3129 ret = event_hist_trigger_parse(&trigger_hist_cmd, file, 3130 "", "hist", cmd); 3131 if (ret) { 3132 kfree(cmd); 3133 kfree(var_hist->cmd); 3134 kfree(var_hist); 3135 hist_err(tr, HIST_ERR_HIST_CREATE_FAIL, errpos(field_name)); 3136 return ERR_PTR(ret); 3137 } 3138 3139 kfree(cmd); 3140 3141 /* If we can't find the variable, something went wrong */ 3142 event_var = find_synthetic_field_var(target_hist_data, subsys_name, 3143 event_name, field_name); 3144 if (IS_ERR_OR_NULL(event_var)) { 3145 kfree(var_hist->cmd); 3146 kfree(var_hist); 3147 hist_err(tr, HIST_ERR_SYNTH_VAR_NOT_FOUND, errpos(field_name)); 3148 return ERR_PTR(-EINVAL); 3149 } 3150 3151 n = target_hist_data->n_field_var_hists; 3152 target_hist_data->field_var_hists[n] = var_hist; 3153 target_hist_data->n_field_var_hists++; 3154 3155 return event_var; 3156 } 3157 3158 static struct hist_field * 3159 find_target_event_var(struct hist_trigger_data *hist_data, 3160 char *subsys_name, char *event_name, char *var_name) 3161 { 3162 struct trace_event_file *file = hist_data->event_file; 3163 struct hist_field *hist_field = NULL; 3164 3165 if (subsys_name) { 3166 struct trace_event_call *call; 3167 3168 if (!event_name) 3169 return NULL; 3170 3171 call = file->event_call; 3172 3173 if (strcmp(subsys_name, call->class->system) != 0) 3174 return NULL; 3175 3176 if (strcmp(event_name, trace_event_name(call)) != 0) 3177 return NULL; 3178 } 3179 3180 hist_field = find_var_field(hist_data, var_name); 3181 3182 return hist_field; 3183 } 3184 3185 static inline void __update_field_vars(struct tracing_map_elt *elt, 3186 struct trace_buffer *buffer, 3187 struct ring_buffer_event *rbe, 3188 void *rec, 3189 struct field_var **field_vars, 3190 unsigned int n_field_vars, 3191 unsigned int field_var_str_start) 3192 { 3193 struct hist_elt_data *elt_data = elt->private_data; 3194 unsigned int i, j, var_idx; 3195 u64 var_val; 3196 3197 /* Make sure stacktrace can fit in the string variable length */ 3198 BUILD_BUG_ON((HIST_STACKTRACE_DEPTH + 1) * sizeof(long) > STR_VAR_LEN_MAX); 3199 3200 for (i = 0, j = field_var_str_start; i < n_field_vars; i++) { 3201 struct field_var *field_var = field_vars[i]; 3202 struct hist_field *var = field_var->var; 3203 struct hist_field *val = field_var->val; 3204 3205 var_val = hist_fn_call(val, elt, buffer, rbe, rec); 3206 var_idx = var->var.idx; 3207 3208 if (val->flags & (HIST_FIELD_FL_STRING | 3209 HIST_FIELD_FL_STACKTRACE)) { 3210 char *str = elt_data->field_var_str[j++]; 3211 char *val_str = (char *)(uintptr_t)var_val; 3212 unsigned int size; 3213 3214 if (val->flags & HIST_FIELD_FL_STRING) { 3215 size = min(val->size, STR_VAR_LEN_MAX); 3216 strscpy(str, val_str, size); 3217 } else { 3218 char *stack_start = str + sizeof(unsigned long); 3219 int e; 3220 3221 e = stack_trace_save((void *)stack_start, 3222 HIST_STACKTRACE_DEPTH, 3223 HIST_STACKTRACE_SKIP); 3224 if (e < HIST_STACKTRACE_DEPTH - 1) 3225 ((unsigned long *)stack_start)[e] = 0; 3226 *((unsigned long *)str) = e; 3227 } 3228 var_val = (u64)(uintptr_t)str; 3229 } 3230 tracing_map_set_var(elt, var_idx, var_val); 3231 } 3232 } 3233 3234 static void update_field_vars(struct hist_trigger_data *hist_data, 3235 struct tracing_map_elt *elt, 3236 struct trace_buffer *buffer, 3237 struct ring_buffer_event *rbe, 3238 void *rec) 3239 { 3240 __update_field_vars(elt, buffer, rbe, rec, hist_data->field_vars, 3241 hist_data->n_field_vars, 0); 3242 } 3243 3244 static void save_track_data_vars(struct hist_trigger_data *hist_data, 3245 struct tracing_map_elt *elt, 3246 struct trace_buffer *buffer, void *rec, 3247 struct ring_buffer_event *rbe, void *key, 3248 struct action_data *data, u64 *var_ref_vals) 3249 { 3250 __update_field_vars(elt, buffer, rbe, rec, hist_data->save_vars, 3251 hist_data->n_save_vars, hist_data->n_field_var_str); 3252 } 3253 3254 static struct hist_field *create_var(struct hist_trigger_data *hist_data, 3255 struct trace_event_file *file, 3256 char *name, int size, const char *type) 3257 { 3258 struct hist_field *var; 3259 int idx; 3260 3261 if (find_var(hist_data, file, name) && !hist_data->remove) { 3262 var = ERR_PTR(-EINVAL); 3263 goto out; 3264 } 3265 3266 var = kzalloc_obj(struct hist_field); 3267 if (!var) { 3268 var = ERR_PTR(-ENOMEM); 3269 goto out; 3270 } 3271 3272 idx = tracing_map_add_var(hist_data->map); 3273 if (idx < 0) { 3274 kfree(var); 3275 var = ERR_PTR(-EINVAL); 3276 goto out; 3277 } 3278 3279 var->ref = 1; 3280 var->flags = HIST_FIELD_FL_VAR; 3281 var->var.idx = idx; 3282 var->var.hist_data = var->hist_data = hist_data; 3283 var->size = size; 3284 var->var.name = kstrdup(name, GFP_KERNEL); 3285 var->type = kstrdup_const(type, GFP_KERNEL); 3286 if (!var->var.name || !var->type) { 3287 kfree_const(var->type); 3288 kfree(var->var.name); 3289 kfree(var); 3290 var = ERR_PTR(-ENOMEM); 3291 } 3292 out: 3293 return var; 3294 } 3295 3296 static struct field_var *create_field_var(struct hist_trigger_data *hist_data, 3297 struct trace_event_file *file, 3298 char *field_name) 3299 { 3300 struct hist_field *val = NULL, *var = NULL; 3301 unsigned long flags = HIST_FIELD_FL_VAR; 3302 struct trace_array *tr = file->tr; 3303 struct field_var *field_var; 3304 int ret = 0; 3305 3306 if (hist_data->n_field_vars >= SYNTH_FIELDS_MAX) { 3307 hist_err(tr, HIST_ERR_TOO_MANY_FIELD_VARS, errpos(field_name)); 3308 ret = -EINVAL; 3309 goto err; 3310 } 3311 3312 val = parse_atom(hist_data, file, field_name, &flags, NULL); 3313 if (IS_ERR(val)) { 3314 hist_err(tr, HIST_ERR_FIELD_VAR_PARSE_FAIL, errpos(field_name)); 3315 ret = PTR_ERR(val); 3316 goto err; 3317 } 3318 3319 var = create_var(hist_data, file, field_name, val->size, val->type); 3320 if (IS_ERR(var)) { 3321 hist_err(tr, HIST_ERR_VAR_CREATE_FIND_FAIL, errpos(field_name)); 3322 destroy_hist_field(val, 0); 3323 ret = PTR_ERR(var); 3324 goto err; 3325 } 3326 3327 field_var = kzalloc_obj(struct field_var); 3328 if (!field_var) { 3329 destroy_hist_field(val, 0); 3330 kfree_const(var->type); 3331 kfree(var->var.name); 3332 kfree(var); 3333 ret = -ENOMEM; 3334 goto err; 3335 } 3336 3337 field_var->var = var; 3338 field_var->val = val; 3339 out: 3340 return field_var; 3341 err: 3342 field_var = ERR_PTR(ret); 3343 goto out; 3344 } 3345 3346 /** 3347 * create_target_field_var - Automatically create a variable for a field 3348 * @target_hist_data: The target hist trigger 3349 * @subsys_name: Optional subsystem name 3350 * @event_name: Optional event name 3351 * @var_name: The name of the field (and the resulting variable) 3352 * 3353 * Hist trigger actions fetch data from variables, not directly from 3354 * events. However, for convenience, users are allowed to directly 3355 * specify an event field in an action, which will be automatically 3356 * converted into a variable on their behalf. 3357 * 3358 * This function creates a field variable with the name var_name on 3359 * the hist trigger currently being defined on the target event. If 3360 * subsys_name and event_name are specified, this function simply 3361 * verifies that they do in fact match the target event subsystem and 3362 * event name. 3363 * 3364 * Return: The variable created for the field. 3365 */ 3366 static struct field_var * 3367 create_target_field_var(struct hist_trigger_data *target_hist_data, 3368 char *subsys_name, char *event_name, char *var_name) 3369 { 3370 struct trace_event_file *file = target_hist_data->event_file; 3371 3372 if (subsys_name) { 3373 struct trace_event_call *call; 3374 3375 if (!event_name) 3376 return NULL; 3377 3378 call = file->event_call; 3379 3380 if (strcmp(subsys_name, call->class->system) != 0) 3381 return NULL; 3382 3383 if (strcmp(event_name, trace_event_name(call)) != 0) 3384 return NULL; 3385 } 3386 3387 return create_field_var(target_hist_data, file, var_name); 3388 } 3389 3390 static bool check_track_val_max(u64 track_val, u64 var_val) 3391 { 3392 if (var_val <= track_val) 3393 return false; 3394 3395 return true; 3396 } 3397 3398 static bool check_track_val_changed(u64 track_val, u64 var_val) 3399 { 3400 if (var_val == track_val) 3401 return false; 3402 3403 return true; 3404 } 3405 3406 static u64 get_track_val(struct hist_trigger_data *hist_data, 3407 struct tracing_map_elt *elt, 3408 struct action_data *data) 3409 { 3410 unsigned int track_var_idx = data->track_data.track_var->var.idx; 3411 u64 track_val; 3412 3413 track_val = tracing_map_read_var(elt, track_var_idx); 3414 3415 return track_val; 3416 } 3417 3418 static void save_track_val(struct hist_trigger_data *hist_data, 3419 struct tracing_map_elt *elt, 3420 struct action_data *data, u64 var_val) 3421 { 3422 unsigned int track_var_idx = data->track_data.track_var->var.idx; 3423 3424 tracing_map_set_var(elt, track_var_idx, var_val); 3425 } 3426 3427 static void save_track_data(struct hist_trigger_data *hist_data, 3428 struct tracing_map_elt *elt, 3429 struct trace_buffer *buffer, void *rec, 3430 struct ring_buffer_event *rbe, void *key, 3431 struct action_data *data, u64 *var_ref_vals) 3432 { 3433 if (data->track_data.save_data) 3434 data->track_data.save_data(hist_data, elt, buffer, rec, rbe, 3435 key, data, var_ref_vals); 3436 } 3437 3438 static bool check_track_val(struct tracing_map_elt *elt, 3439 struct action_data *data, 3440 u64 var_val) 3441 { 3442 struct hist_trigger_data *hist_data; 3443 u64 track_val; 3444 3445 hist_data = data->track_data.track_var->hist_data; 3446 track_val = get_track_val(hist_data, elt, data); 3447 3448 return data->track_data.check_val(track_val, var_val); 3449 } 3450 3451 #ifdef CONFIG_TRACER_SNAPSHOT 3452 static bool cond_snapshot_update(struct trace_array *tr, void *cond_data) 3453 { 3454 /* called with tr->max_lock held */ 3455 struct track_data *track_data = tr->cond_snapshot->cond_data; 3456 struct hist_elt_data *elt_data, *track_elt_data; 3457 struct snapshot_context *context = cond_data; 3458 struct action_data *action; 3459 u64 track_val; 3460 3461 if (!track_data) 3462 return false; 3463 3464 action = track_data->action_data; 3465 3466 track_val = get_track_val(track_data->hist_data, context->elt, 3467 track_data->action_data); 3468 3469 if (!action->track_data.check_val(track_data->track_val, track_val)) 3470 return false; 3471 3472 track_data->track_val = track_val; 3473 memcpy(track_data->key, context->key, track_data->key_len); 3474 3475 elt_data = context->elt->private_data; 3476 track_elt_data = track_data->elt.private_data; 3477 if (elt_data->comm) 3478 strscpy(track_elt_data->comm, elt_data->comm, TASK_COMM_LEN); 3479 3480 track_data->updated = true; 3481 3482 return true; 3483 } 3484 3485 static void save_track_data_snapshot(struct hist_trigger_data *hist_data, 3486 struct tracing_map_elt *elt, 3487 struct trace_buffer *buffer, void *rec, 3488 struct ring_buffer_event *rbe, void *key, 3489 struct action_data *data, 3490 u64 *var_ref_vals) 3491 { 3492 struct trace_event_file *file = hist_data->event_file; 3493 struct snapshot_context context; 3494 3495 context.elt = elt; 3496 context.key = key; 3497 3498 tracing_snapshot_cond(file->tr, &context); 3499 } 3500 3501 static void hist_trigger_print_key(struct seq_file *m, 3502 struct hist_trigger_data *hist_data, 3503 void *key, 3504 struct tracing_map_elt *elt); 3505 3506 static struct action_data *snapshot_action(struct hist_trigger_data *hist_data) 3507 { 3508 unsigned int i; 3509 3510 if (!hist_data->n_actions) 3511 return NULL; 3512 3513 for (i = 0; i < hist_data->n_actions; i++) { 3514 struct action_data *data = hist_data->actions[i]; 3515 3516 if (data->action == ACTION_SNAPSHOT) 3517 return data; 3518 } 3519 3520 return NULL; 3521 } 3522 3523 static void track_data_snapshot_print(struct seq_file *m, 3524 struct hist_trigger_data *hist_data) 3525 { 3526 struct trace_event_file *file = hist_data->event_file; 3527 struct track_data *track_data; 3528 struct action_data *action; 3529 3530 track_data = tracing_cond_snapshot_data(file->tr); 3531 if (!track_data) 3532 return; 3533 3534 if (!track_data->updated) 3535 return; 3536 3537 action = snapshot_action(hist_data); 3538 if (!action) 3539 return; 3540 3541 seq_puts(m, "\nSnapshot taken (see tracing/snapshot). Details:\n"); 3542 seq_printf(m, "\ttriggering value { %s(%s) }: %10llu", 3543 action->handler == HANDLER_ONMAX ? "onmax" : "onchange", 3544 action->track_data.var_str, track_data->track_val); 3545 3546 seq_puts(m, "\ttriggered by event with key: "); 3547 hist_trigger_print_key(m, hist_data, track_data->key, &track_data->elt); 3548 seq_putc(m, '\n'); 3549 } 3550 #else 3551 static bool cond_snapshot_update(struct trace_array *tr, void *cond_data) 3552 { 3553 return false; 3554 } 3555 static void save_track_data_snapshot(struct hist_trigger_data *hist_data, 3556 struct tracing_map_elt *elt, 3557 struct trace_buffer *buffer, void *rec, 3558 struct ring_buffer_event *rbe, void *key, 3559 struct action_data *data, 3560 u64 *var_ref_vals) {} 3561 static void track_data_snapshot_print(struct seq_file *m, 3562 struct hist_trigger_data *hist_data) {} 3563 #endif /* CONFIG_TRACER_SNAPSHOT */ 3564 3565 static void track_data_print(struct seq_file *m, 3566 struct hist_trigger_data *hist_data, 3567 struct tracing_map_elt *elt, 3568 struct action_data *data) 3569 { 3570 u64 track_val = get_track_val(hist_data, elt, data); 3571 unsigned int i, save_var_idx; 3572 3573 if (data->handler == HANDLER_ONMAX) 3574 seq_printf(m, "\n\tmax: %10llu", track_val); 3575 else if (data->handler == HANDLER_ONCHANGE) 3576 seq_printf(m, "\n\tchanged: %10llu", track_val); 3577 3578 if (data->action == ACTION_SNAPSHOT) 3579 return; 3580 3581 for (i = 0; i < hist_data->n_save_vars; i++) { 3582 struct hist_field *save_val = hist_data->save_vars[i]->val; 3583 struct hist_field *save_var = hist_data->save_vars[i]->var; 3584 u64 val; 3585 3586 save_var_idx = save_var->var.idx; 3587 3588 val = tracing_map_read_var(elt, save_var_idx); 3589 3590 if (save_val->flags & HIST_FIELD_FL_STRING) { 3591 seq_printf(m, " %s: %-32s", save_var->var.name, 3592 (char *)(uintptr_t)(val)); 3593 } else 3594 seq_printf(m, " %s: %10llu", save_var->var.name, val); 3595 } 3596 } 3597 3598 static void ontrack_action(struct hist_trigger_data *hist_data, 3599 struct tracing_map_elt *elt, 3600 struct trace_buffer *buffer, void *rec, 3601 struct ring_buffer_event *rbe, void *key, 3602 struct action_data *data, u64 *var_ref_vals) 3603 { 3604 u64 var_val = var_ref_vals[data->track_data.var_ref->var_ref_idx]; 3605 3606 if (check_track_val(elt, data, var_val)) { 3607 save_track_val(hist_data, elt, data, var_val); 3608 save_track_data(hist_data, elt, buffer, rec, rbe, 3609 key, data, var_ref_vals); 3610 } 3611 } 3612 3613 static void action_data_destroy(struct action_data *data) 3614 { 3615 unsigned int i; 3616 3617 lockdep_assert_held(&event_mutex); 3618 3619 kfree(data->action_name); 3620 3621 for (i = 0; i < data->n_params; i++) 3622 kfree(data->params[i]); 3623 3624 if (data->synth_event) 3625 data->synth_event->ref--; 3626 3627 kfree(data->synth_event_name); 3628 3629 kfree(data); 3630 } 3631 3632 static void track_data_destroy(struct hist_trigger_data *hist_data, 3633 struct action_data *data) 3634 { 3635 struct trace_event_file *file = hist_data->event_file; 3636 3637 destroy_hist_field(data->track_data.track_var, 0); 3638 3639 if (data->action == ACTION_SNAPSHOT) { 3640 struct track_data *track_data; 3641 3642 track_data = tracing_cond_snapshot_data(file->tr); 3643 if (track_data && track_data->hist_data == hist_data) { 3644 tracing_snapshot_cond_disable(file->tr); 3645 track_data_free(track_data); 3646 } 3647 } 3648 3649 kfree(data->track_data.var_str); 3650 3651 action_data_destroy(data); 3652 } 3653 3654 static int action_create(struct hist_trigger_data *hist_data, 3655 struct action_data *data); 3656 3657 static int track_data_create(struct hist_trigger_data *hist_data, 3658 struct action_data *data) 3659 { 3660 struct hist_field *var_field, *ref_field, *track_var = NULL; 3661 struct trace_event_file *file = hist_data->event_file; 3662 struct trace_array *tr = file->tr; 3663 char *track_data_var_str; 3664 int ret = 0; 3665 3666 track_data_var_str = data->track_data.var_str; 3667 if (track_data_var_str[0] != '$') { 3668 hist_err(tr, HIST_ERR_ONX_NOT_VAR, errpos(track_data_var_str)); 3669 return -EINVAL; 3670 } 3671 track_data_var_str++; 3672 3673 var_field = find_target_event_var(hist_data, NULL, NULL, track_data_var_str); 3674 if (!var_field) { 3675 hist_err(tr, HIST_ERR_ONX_VAR_NOT_FOUND, errpos(track_data_var_str)); 3676 return -EINVAL; 3677 } 3678 3679 ref_field = create_var_ref(hist_data, var_field, NULL, NULL); 3680 if (!ref_field) 3681 return -ENOMEM; 3682 3683 data->track_data.var_ref = ref_field; 3684 3685 if (data->handler == HANDLER_ONMAX) 3686 track_var = create_var(hist_data, file, "__max", sizeof(u64), "u64"); 3687 if (IS_ERR(track_var)) { 3688 hist_err(tr, HIST_ERR_ONX_VAR_CREATE_FAIL, 0); 3689 ret = PTR_ERR(track_var); 3690 goto out; 3691 } 3692 3693 if (data->handler == HANDLER_ONCHANGE) 3694 track_var = create_var(hist_data, file, "__change", sizeof(u64), "u64"); 3695 if (IS_ERR(track_var)) { 3696 hist_err(tr, HIST_ERR_ONX_VAR_CREATE_FAIL, 0); 3697 ret = PTR_ERR(track_var); 3698 goto out; 3699 } 3700 data->track_data.track_var = track_var; 3701 3702 ret = action_create(hist_data, data); 3703 out: 3704 return ret; 3705 } 3706 3707 static int parse_action_params(struct trace_array *tr, char *params, 3708 struct action_data *data) 3709 { 3710 char *param, *saved_param; 3711 bool first_param = true; 3712 int ret = 0; 3713 3714 while (params) { 3715 if (data->n_params >= SYNTH_FIELDS_MAX) { 3716 hist_err(tr, HIST_ERR_TOO_MANY_PARAMS, 0); 3717 ret = -EINVAL; 3718 goto out; 3719 } 3720 3721 param = strsep(¶ms, ","); 3722 if (!param) { 3723 hist_err(tr, HIST_ERR_PARAM_NOT_FOUND, 0); 3724 ret = -EINVAL; 3725 goto out; 3726 } 3727 3728 param = strstrip(param); 3729 if (strlen(param) < 2) { 3730 hist_err(tr, HIST_ERR_INVALID_PARAM, errpos(param)); 3731 ret = -EINVAL; 3732 goto out; 3733 } 3734 3735 saved_param = kstrdup(param, GFP_KERNEL); 3736 if (!saved_param) { 3737 ret = -ENOMEM; 3738 goto out; 3739 } 3740 3741 if (first_param && data->use_trace_keyword) { 3742 data->synth_event_name = saved_param; 3743 first_param = false; 3744 continue; 3745 } 3746 first_param = false; 3747 3748 data->params[data->n_params++] = saved_param; 3749 } 3750 out: 3751 return ret; 3752 } 3753 3754 static int action_parse(struct trace_array *tr, char *str, struct action_data *data, 3755 enum handler_id handler) 3756 { 3757 char *action_name; 3758 int ret = 0; 3759 3760 strsep(&str, "."); 3761 if (!str) { 3762 hist_err(tr, HIST_ERR_ACTION_NOT_FOUND, 0); 3763 ret = -EINVAL; 3764 goto out; 3765 } 3766 3767 action_name = strsep(&str, "("); 3768 if (!action_name || !str) { 3769 hist_err(tr, HIST_ERR_ACTION_NOT_FOUND, 0); 3770 ret = -EINVAL; 3771 goto out; 3772 } 3773 3774 if (str_has_prefix(action_name, "save")) { 3775 char *params = strsep(&str, ")"); 3776 3777 if (!params) { 3778 hist_err(tr, HIST_ERR_NO_SAVE_PARAMS, 0); 3779 ret = -EINVAL; 3780 goto out; 3781 } 3782 3783 ret = parse_action_params(tr, params, data); 3784 if (ret) 3785 goto out; 3786 3787 if (handler == HANDLER_ONMAX) 3788 data->track_data.check_val = check_track_val_max; 3789 else if (handler == HANDLER_ONCHANGE) 3790 data->track_data.check_val = check_track_val_changed; 3791 else { 3792 hist_err(tr, HIST_ERR_ACTION_MISMATCH, errpos(action_name)); 3793 ret = -EINVAL; 3794 goto out; 3795 } 3796 3797 data->track_data.save_data = save_track_data_vars; 3798 data->fn = ontrack_action; 3799 data->action = ACTION_SAVE; 3800 } else if (str_has_prefix(action_name, "snapshot")) { 3801 char *params = strsep(&str, ")"); 3802 3803 if (!str) { 3804 hist_err(tr, HIST_ERR_NO_CLOSING_PAREN, errpos(params)); 3805 ret = -EINVAL; 3806 goto out; 3807 } 3808 3809 if (handler == HANDLER_ONMAX) 3810 data->track_data.check_val = check_track_val_max; 3811 else if (handler == HANDLER_ONCHANGE) 3812 data->track_data.check_val = check_track_val_changed; 3813 else { 3814 hist_err(tr, HIST_ERR_ACTION_MISMATCH, errpos(action_name)); 3815 ret = -EINVAL; 3816 goto out; 3817 } 3818 3819 data->track_data.save_data = save_track_data_snapshot; 3820 data->fn = ontrack_action; 3821 data->action = ACTION_SNAPSHOT; 3822 } else { 3823 char *params = strsep(&str, ")"); 3824 3825 if (str_has_prefix(action_name, "trace")) 3826 data->use_trace_keyword = true; 3827 3828 if (params) { 3829 ret = parse_action_params(tr, params, data); 3830 if (ret) 3831 goto out; 3832 } 3833 3834 if (handler == HANDLER_ONMAX) 3835 data->track_data.check_val = check_track_val_max; 3836 else if (handler == HANDLER_ONCHANGE) 3837 data->track_data.check_val = check_track_val_changed; 3838 3839 if (handler != HANDLER_ONMATCH) { 3840 data->track_data.save_data = action_trace; 3841 data->fn = ontrack_action; 3842 } else 3843 data->fn = action_trace; 3844 3845 data->action = ACTION_TRACE; 3846 } 3847 3848 data->action_name = kstrdup(action_name, GFP_KERNEL); 3849 if (!data->action_name) { 3850 ret = -ENOMEM; 3851 goto out; 3852 } 3853 3854 data->handler = handler; 3855 out: 3856 return ret; 3857 } 3858 3859 static struct action_data *track_data_parse(struct hist_trigger_data *hist_data, 3860 char *str, enum handler_id handler) 3861 { 3862 struct action_data *data; 3863 int ret = -EINVAL; 3864 char *var_str; 3865 3866 data = kzalloc_obj(*data); 3867 if (!data) 3868 return ERR_PTR(-ENOMEM); 3869 3870 var_str = strsep(&str, ")"); 3871 if (!var_str || !str) { 3872 ret = -EINVAL; 3873 goto free; 3874 } 3875 3876 data->track_data.var_str = kstrdup(var_str, GFP_KERNEL); 3877 if (!data->track_data.var_str) { 3878 ret = -ENOMEM; 3879 goto free; 3880 } 3881 3882 ret = action_parse(hist_data->event_file->tr, str, data, handler); 3883 if (ret) 3884 goto free; 3885 out: 3886 return data; 3887 free: 3888 track_data_destroy(hist_data, data); 3889 data = ERR_PTR(ret); 3890 goto out; 3891 } 3892 3893 static void onmatch_destroy(struct action_data *data) 3894 { 3895 kfree(data->match_data.event); 3896 kfree(data->match_data.event_system); 3897 3898 action_data_destroy(data); 3899 } 3900 3901 static void destroy_field_var(struct field_var *field_var) 3902 { 3903 if (!field_var) 3904 return; 3905 3906 destroy_hist_field(field_var->var, 0); 3907 destroy_hist_field(field_var->val, 0); 3908 3909 kfree(field_var); 3910 } 3911 3912 static void destroy_field_vars(struct hist_trigger_data *hist_data) 3913 { 3914 unsigned int i; 3915 3916 for (i = 0; i < hist_data->n_field_vars; i++) 3917 destroy_field_var(hist_data->field_vars[i]); 3918 3919 for (i = 0; i < hist_data->n_save_vars; i++) 3920 destroy_field_var(hist_data->save_vars[i]); 3921 } 3922 3923 static void save_field_var(struct hist_trigger_data *hist_data, 3924 struct field_var *field_var) 3925 { 3926 hist_data->field_vars[hist_data->n_field_vars++] = field_var; 3927 3928 /* Stack traces are saved in the string storage too */ 3929 if (field_var->val->flags & (HIST_FIELD_FL_STRING | HIST_FIELD_FL_STACKTRACE)) 3930 hist_data->n_field_var_str++; 3931 } 3932 3933 3934 static int check_synth_field(struct synth_event *event, 3935 struct hist_field *hist_field, 3936 unsigned int field_pos) 3937 { 3938 struct synth_field *field; 3939 3940 if (field_pos >= event->n_fields) 3941 return -EINVAL; 3942 3943 field = event->fields[field_pos]; 3944 3945 /* 3946 * A dynamic string synth field can accept static or 3947 * dynamic. A static string synth field can only accept a 3948 * same-sized static string, which is checked for later. 3949 */ 3950 if (strstr(hist_field->type, "char[") && field->is_string 3951 && field->is_dynamic) 3952 return 0; 3953 3954 if (strstr(hist_field->type, "long[") && field->is_stack) 3955 return 0; 3956 3957 if (strcmp(field->type, hist_field->type) != 0) { 3958 if (field->size != hist_field->size || 3959 (!field->is_string && field->is_signed != hist_field->is_signed)) 3960 return -EINVAL; 3961 } 3962 3963 return 0; 3964 } 3965 3966 static struct hist_field * 3967 trace_action_find_var(struct hist_trigger_data *hist_data, 3968 struct action_data *data, 3969 char *system, char *event, char *var) 3970 { 3971 struct trace_array *tr = hist_data->event_file->tr; 3972 struct hist_field *hist_field; 3973 3974 var++; /* skip '$' */ 3975 3976 hist_field = find_target_event_var(hist_data, system, event, var); 3977 if (!hist_field) { 3978 if (!system && data->handler == HANDLER_ONMATCH) { 3979 system = data->match_data.event_system; 3980 event = data->match_data.event; 3981 } 3982 3983 hist_field = find_event_var(hist_data, system, event, var); 3984 } 3985 3986 if (!hist_field) 3987 hist_err(tr, HIST_ERR_PARAM_NOT_FOUND, errpos(var)); 3988 3989 return hist_field; 3990 } 3991 3992 static struct hist_field * 3993 trace_action_create_field_var(struct hist_trigger_data *hist_data, 3994 struct action_data *data, char *system, 3995 char *event, char *var) 3996 { 3997 struct hist_field *hist_field = NULL; 3998 struct field_var *field_var; 3999 4000 /* 4001 * First try to create a field var on the target event (the 4002 * currently being defined). This will create a variable for 4003 * unqualified fields on the target event, or if qualified, 4004 * target fields that have qualified names matching the target. 4005 */ 4006 field_var = create_target_field_var(hist_data, system, event, var); 4007 4008 if (field_var && !IS_ERR(field_var)) { 4009 save_field_var(hist_data, field_var); 4010 hist_field = field_var->var; 4011 } else { 4012 field_var = NULL; 4013 /* 4014 * If no explicit system.event is specified, default to 4015 * looking for fields on the onmatch(system.event.xxx) 4016 * event. 4017 */ 4018 if (!system && data->handler == HANDLER_ONMATCH) { 4019 system = data->match_data.event_system; 4020 event = data->match_data.event; 4021 } 4022 4023 if (!event) 4024 goto free; 4025 /* 4026 * At this point, we're looking at a field on another 4027 * event. Because we can't modify a hist trigger on 4028 * another event to add a variable for a field, we need 4029 * to create a new trigger on that event and create the 4030 * variable at the same time. 4031 */ 4032 hist_field = create_field_var_hist(hist_data, system, event, var); 4033 if (IS_ERR(hist_field)) 4034 goto free; 4035 } 4036 out: 4037 return hist_field; 4038 free: 4039 destroy_field_var(field_var); 4040 hist_field = NULL; 4041 goto out; 4042 } 4043 4044 static int trace_action_create(struct hist_trigger_data *hist_data, 4045 struct action_data *data) 4046 { 4047 struct trace_array *tr = hist_data->event_file->tr; 4048 char *event_name, *param, *system = NULL; 4049 struct hist_field *hist_field, *var_ref; 4050 unsigned int i; 4051 unsigned int field_pos = 0; 4052 struct synth_event *event; 4053 char *synth_event_name; 4054 int var_ref_idx, ret = 0; 4055 4056 lockdep_assert_held(&event_mutex); 4057 4058 /* Sanity check to avoid out-of-bound write on 'data->var_ref_idx' */ 4059 if (data->n_params > SYNTH_FIELDS_MAX) 4060 return -EINVAL; 4061 4062 if (data->use_trace_keyword) 4063 synth_event_name = data->synth_event_name; 4064 else 4065 synth_event_name = data->action_name; 4066 4067 event = find_synth_event(synth_event_name); 4068 if (!event) { 4069 hist_err(tr, HIST_ERR_SYNTH_EVENT_NOT_FOUND, errpos(synth_event_name)); 4070 return -EINVAL; 4071 } 4072 4073 event->ref++; 4074 4075 for (i = 0; i < data->n_params; i++) { 4076 char *p; 4077 4078 p = param = kstrdup(data->params[i], GFP_KERNEL); 4079 if (!param) { 4080 ret = -ENOMEM; 4081 goto err; 4082 } 4083 4084 system = strsep(¶m, "."); 4085 if (!param) { 4086 param = (char *)system; 4087 system = event_name = NULL; 4088 } else { 4089 event_name = strsep(¶m, "."); 4090 if (!param) { 4091 kfree(p); 4092 ret = -EINVAL; 4093 goto err; 4094 } 4095 } 4096 4097 if (param[0] == '$') 4098 hist_field = trace_action_find_var(hist_data, data, 4099 system, event_name, 4100 param); 4101 else 4102 hist_field = trace_action_create_field_var(hist_data, 4103 data, 4104 system, 4105 event_name, 4106 param); 4107 4108 if (!hist_field) { 4109 kfree(p); 4110 ret = -EINVAL; 4111 goto err; 4112 } 4113 4114 if (check_synth_field(event, hist_field, field_pos) == 0) { 4115 var_ref = create_var_ref(hist_data, hist_field, 4116 system, event_name); 4117 if (!var_ref) { 4118 kfree(p); 4119 ret = -ENOMEM; 4120 goto err; 4121 } 4122 4123 var_ref_idx = find_var_ref_idx(hist_data, var_ref); 4124 if (WARN_ON(var_ref_idx < 0)) { 4125 kfree(p); 4126 ret = var_ref_idx; 4127 goto err; 4128 } 4129 4130 data->var_ref_idx[i] = var_ref_idx; 4131 4132 field_pos++; 4133 kfree(p); 4134 continue; 4135 } 4136 4137 hist_err(tr, HIST_ERR_SYNTH_TYPE_MISMATCH, errpos(param)); 4138 kfree(p); 4139 ret = -EINVAL; 4140 goto err; 4141 } 4142 4143 if (field_pos != event->n_fields) { 4144 hist_err(tr, HIST_ERR_SYNTH_COUNT_MISMATCH, errpos(event->name)); 4145 ret = -EINVAL; 4146 goto err; 4147 } 4148 4149 data->synth_event = event; 4150 out: 4151 return ret; 4152 err: 4153 event->ref--; 4154 4155 goto out; 4156 } 4157 4158 static int action_create(struct hist_trigger_data *hist_data, 4159 struct action_data *data) 4160 { 4161 struct trace_event_file *file = hist_data->event_file; 4162 struct trace_array *tr = file->tr; 4163 struct track_data *track_data; 4164 struct field_var *field_var; 4165 unsigned int i; 4166 char *param; 4167 int ret = 0; 4168 4169 if (data->action == ACTION_TRACE) 4170 return trace_action_create(hist_data, data); 4171 4172 if (data->action == ACTION_SNAPSHOT) { 4173 track_data = track_data_alloc(hist_data->key_size, data, hist_data); 4174 if (IS_ERR(track_data)) { 4175 ret = PTR_ERR(track_data); 4176 goto out; 4177 } 4178 4179 ret = tracing_snapshot_cond_enable(file->tr, track_data, 4180 cond_snapshot_update); 4181 if (ret) 4182 track_data_free(track_data); 4183 4184 goto out; 4185 } 4186 4187 if (data->action == ACTION_SAVE) { 4188 if (hist_data->n_save_vars) { 4189 ret = -EEXIST; 4190 hist_err(tr, HIST_ERR_TOO_MANY_SAVE_ACTIONS, 0); 4191 goto out; 4192 } 4193 4194 for (i = 0; i < data->n_params; i++) { 4195 param = kstrdup(data->params[i], GFP_KERNEL); 4196 if (!param) { 4197 ret = -ENOMEM; 4198 goto out; 4199 } 4200 4201 field_var = create_target_field_var(hist_data, NULL, NULL, param); 4202 if (IS_ERR(field_var)) { 4203 hist_err(tr, HIST_ERR_FIELD_VAR_CREATE_FAIL, 4204 errpos(param)); 4205 ret = PTR_ERR(field_var); 4206 kfree(param); 4207 goto out; 4208 } 4209 4210 hist_data->save_vars[hist_data->n_save_vars++] = field_var; 4211 if (field_var->val->flags & 4212 (HIST_FIELD_FL_STRING | HIST_FIELD_FL_STACKTRACE)) 4213 hist_data->n_save_var_str++; 4214 kfree(param); 4215 } 4216 } 4217 out: 4218 return ret; 4219 } 4220 4221 static int onmatch_create(struct hist_trigger_data *hist_data, 4222 struct action_data *data) 4223 { 4224 return action_create(hist_data, data); 4225 } 4226 4227 static struct action_data *onmatch_parse(struct trace_array *tr, char *str) 4228 { 4229 char *match_event, *match_event_system; 4230 struct action_data *data; 4231 int ret = -EINVAL; 4232 4233 data = kzalloc_obj(*data); 4234 if (!data) 4235 return ERR_PTR(-ENOMEM); 4236 4237 match_event = strsep(&str, ")"); 4238 if (!match_event || !str) { 4239 hist_err(tr, HIST_ERR_NO_CLOSING_PAREN, errpos(match_event)); 4240 goto free; 4241 } 4242 4243 match_event_system = strsep(&match_event, "."); 4244 if (!match_event) { 4245 hist_err(tr, HIST_ERR_SUBSYS_NOT_FOUND, errpos(match_event_system)); 4246 goto free; 4247 } 4248 4249 if (IS_ERR(event_file(tr, match_event_system, match_event))) { 4250 hist_err(tr, HIST_ERR_INVALID_SUBSYS_EVENT, errpos(match_event)); 4251 goto free; 4252 } 4253 4254 data->match_data.event = kstrdup(match_event, GFP_KERNEL); 4255 if (!data->match_data.event) { 4256 ret = -ENOMEM; 4257 goto free; 4258 } 4259 4260 data->match_data.event_system = kstrdup(match_event_system, GFP_KERNEL); 4261 if (!data->match_data.event_system) { 4262 ret = -ENOMEM; 4263 goto free; 4264 } 4265 4266 ret = action_parse(tr, str, data, HANDLER_ONMATCH); 4267 if (ret) 4268 goto free; 4269 out: 4270 return data; 4271 free: 4272 onmatch_destroy(data); 4273 data = ERR_PTR(ret); 4274 goto out; 4275 } 4276 4277 static int create_hitcount_val(struct hist_trigger_data *hist_data) 4278 { 4279 hist_data->fields[HITCOUNT_IDX] = 4280 create_hist_field(hist_data, NULL, HIST_FIELD_FL_HITCOUNT, NULL); 4281 if (!hist_data->fields[HITCOUNT_IDX]) 4282 return -ENOMEM; 4283 4284 hist_data->n_vals++; 4285 hist_data->n_fields++; 4286 4287 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX)) 4288 return -EINVAL; 4289 4290 return 0; 4291 } 4292 4293 static int __create_val_field(struct hist_trigger_data *hist_data, 4294 unsigned int val_idx, 4295 struct trace_event_file *file, 4296 char *var_name, char *field_str, 4297 unsigned long flags) 4298 { 4299 struct hist_field *hist_field; 4300 int ret = 0, n_subexprs = 0; 4301 4302 hist_field = parse_expr(hist_data, file, field_str, flags, var_name, &n_subexprs); 4303 if (IS_ERR(hist_field)) { 4304 ret = PTR_ERR(hist_field); 4305 goto out; 4306 } 4307 4308 /* values and variables should not have some modifiers */ 4309 if (hist_field->flags & HIST_FIELD_FL_VAR) { 4310 /* Variable */ 4311 if (hist_field->flags & (HIST_FIELD_FL_GRAPH | HIST_FIELD_FL_PERCENT | 4312 HIST_FIELD_FL_BUCKET | HIST_FIELD_FL_LOG2)) 4313 goto err; 4314 } else { 4315 /* Value */ 4316 if (hist_field->flags & (HIST_FIELD_FL_GRAPH | HIST_FIELD_FL_PERCENT | 4317 HIST_FIELD_FL_BUCKET | HIST_FIELD_FL_LOG2 | 4318 HIST_FIELD_FL_SYM | HIST_FIELD_FL_SYM_OFFSET | 4319 HIST_FIELD_FL_SYSCALL | HIST_FIELD_FL_STACKTRACE)) 4320 goto err; 4321 } 4322 4323 hist_data->fields[val_idx] = hist_field; 4324 4325 ++hist_data->n_vals; 4326 ++hist_data->n_fields; 4327 4328 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX)) 4329 ret = -EINVAL; 4330 out: 4331 return ret; 4332 err: 4333 hist_err(file->tr, HIST_ERR_BAD_FIELD_MODIFIER, errpos(field_str)); 4334 return -EINVAL; 4335 } 4336 4337 static int create_val_field(struct hist_trigger_data *hist_data, 4338 unsigned int val_idx, 4339 struct trace_event_file *file, 4340 char *field_str) 4341 { 4342 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX)) 4343 return -EINVAL; 4344 4345 return __create_val_field(hist_data, val_idx, file, NULL, field_str, 0); 4346 } 4347 4348 static const char no_comm[] = "(no comm)"; 4349 4350 static u64 hist_field_execname(struct hist_field *hist_field, 4351 struct tracing_map_elt *elt, 4352 struct trace_buffer *buffer, 4353 struct ring_buffer_event *rbe, 4354 void *event) 4355 { 4356 struct hist_elt_data *elt_data; 4357 4358 if (WARN_ON_ONCE(!elt)) 4359 return (u64)(unsigned long)no_comm; 4360 4361 elt_data = elt->private_data; 4362 4363 if (WARN_ON_ONCE(!elt_data->comm)) 4364 return (u64)(unsigned long)no_comm; 4365 4366 return (u64)(unsigned long)(elt_data->comm); 4367 } 4368 4369 static u64 hist_field_stack(struct hist_field *hist_field, 4370 struct tracing_map_elt *elt, 4371 struct trace_buffer *buffer, 4372 struct ring_buffer_event *rbe, 4373 void *event) 4374 { 4375 u32 str_item = *(u32 *)(event + hist_field->field->offset); 4376 int str_loc = str_item & 0xffff; 4377 char *addr = (char *)(event + str_loc); 4378 4379 return (u64)(unsigned long)addr; 4380 } 4381 4382 static u64 hist_fn_call(struct hist_field *hist_field, 4383 struct tracing_map_elt *elt, 4384 struct trace_buffer *buffer, 4385 struct ring_buffer_event *rbe, 4386 void *event) 4387 { 4388 switch (hist_field->fn_num) { 4389 case HIST_FIELD_FN_VAR_REF: 4390 return hist_field_var_ref(hist_field, elt, buffer, rbe, event); 4391 case HIST_FIELD_FN_COUNTER: 4392 return hist_field_counter(hist_field, elt, buffer, rbe, event); 4393 case HIST_FIELD_FN_CONST: 4394 return hist_field_const(hist_field, elt, buffer, rbe, event); 4395 case HIST_FIELD_FN_LOG2: 4396 return hist_field_log2(hist_field, elt, buffer, rbe, event); 4397 case HIST_FIELD_FN_BUCKET: 4398 return hist_field_bucket(hist_field, elt, buffer, rbe, event); 4399 case HIST_FIELD_FN_TIMESTAMP: 4400 return hist_field_timestamp(hist_field, elt, buffer, rbe, event); 4401 case HIST_FIELD_FN_CPU: 4402 return hist_field_cpu(hist_field, elt, buffer, rbe, event); 4403 case HIST_FIELD_FN_COMM: 4404 return hist_field_comm(hist_field, elt, buffer, rbe, event); 4405 case HIST_FIELD_FN_STRING: 4406 return hist_field_string(hist_field, elt, buffer, rbe, event); 4407 case HIST_FIELD_FN_DYNSTRING: 4408 return hist_field_dynstring(hist_field, elt, buffer, rbe, event); 4409 case HIST_FIELD_FN_RELDYNSTRING: 4410 return hist_field_reldynstring(hist_field, elt, buffer, rbe, event); 4411 case HIST_FIELD_FN_PSTRING: 4412 return hist_field_pstring(hist_field, elt, buffer, rbe, event); 4413 case HIST_FIELD_FN_S64: 4414 return hist_field_s64(hist_field, elt, buffer, rbe, event); 4415 case HIST_FIELD_FN_U64: 4416 return hist_field_u64(hist_field, elt, buffer, rbe, event); 4417 case HIST_FIELD_FN_S32: 4418 return hist_field_s32(hist_field, elt, buffer, rbe, event); 4419 case HIST_FIELD_FN_U32: 4420 return hist_field_u32(hist_field, elt, buffer, rbe, event); 4421 case HIST_FIELD_FN_S16: 4422 return hist_field_s16(hist_field, elt, buffer, rbe, event); 4423 case HIST_FIELD_FN_U16: 4424 return hist_field_u16(hist_field, elt, buffer, rbe, event); 4425 case HIST_FIELD_FN_S8: 4426 return hist_field_s8(hist_field, elt, buffer, rbe, event); 4427 case HIST_FIELD_FN_U8: 4428 return hist_field_u8(hist_field, elt, buffer, rbe, event); 4429 case HIST_FIELD_FN_UMINUS: 4430 return hist_field_unary_minus(hist_field, elt, buffer, rbe, event); 4431 case HIST_FIELD_FN_MINUS: 4432 return hist_field_minus(hist_field, elt, buffer, rbe, event); 4433 case HIST_FIELD_FN_PLUS: 4434 return hist_field_plus(hist_field, elt, buffer, rbe, event); 4435 case HIST_FIELD_FN_DIV: 4436 return hist_field_div(hist_field, elt, buffer, rbe, event); 4437 case HIST_FIELD_FN_MULT: 4438 return hist_field_mult(hist_field, elt, buffer, rbe, event); 4439 case HIST_FIELD_FN_DIV_POWER2: 4440 return div_by_power_of_two(hist_field, elt, buffer, rbe, event); 4441 case HIST_FIELD_FN_DIV_NOT_POWER2: 4442 return div_by_not_power_of_two(hist_field, elt, buffer, rbe, event); 4443 case HIST_FIELD_FN_DIV_MULT_SHIFT: 4444 return div_by_mult_and_shift(hist_field, elt, buffer, rbe, event); 4445 case HIST_FIELD_FN_EXECNAME: 4446 return hist_field_execname(hist_field, elt, buffer, rbe, event); 4447 case HIST_FIELD_FN_STACK: 4448 return hist_field_stack(hist_field, elt, buffer, rbe, event); 4449 default: 4450 return 0; 4451 } 4452 } 4453 4454 /* Convert a var that points to common_pid.execname to a string */ 4455 static void update_var_execname(struct hist_field *hist_field) 4456 { 4457 hist_field->flags = HIST_FIELD_FL_STRING | HIST_FIELD_FL_VAR | 4458 HIST_FIELD_FL_EXECNAME; 4459 hist_field->size = MAX_FILTER_STR_VAL; 4460 hist_field->is_signed = 0; 4461 4462 kfree_const(hist_field->type); 4463 hist_field->type = "char[]"; 4464 4465 hist_field->fn_num = HIST_FIELD_FN_EXECNAME; 4466 } 4467 4468 static int create_var_field(struct hist_trigger_data *hist_data, 4469 unsigned int val_idx, 4470 struct trace_event_file *file, 4471 char *var_name, char *expr_str) 4472 { 4473 struct trace_array *tr = hist_data->event_file->tr; 4474 unsigned long flags = 0; 4475 int ret; 4476 4477 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX)) 4478 return -EINVAL; 4479 4480 if (find_var(hist_data, file, var_name) && !hist_data->remove) { 4481 hist_err(tr, HIST_ERR_DUPLICATE_VAR, errpos(var_name)); 4482 return -EINVAL; 4483 } 4484 4485 flags |= HIST_FIELD_FL_VAR; 4486 hist_data->n_vars++; 4487 if (WARN_ON(hist_data->n_vars > TRACING_MAP_VARS_MAX)) 4488 return -EINVAL; 4489 4490 ret = __create_val_field(hist_data, val_idx, file, var_name, expr_str, flags); 4491 4492 if (!ret && hist_data->fields[val_idx]->flags & HIST_FIELD_FL_EXECNAME) 4493 update_var_execname(hist_data->fields[val_idx]); 4494 4495 if (!ret && hist_data->fields[val_idx]->flags & 4496 (HIST_FIELD_FL_STRING | HIST_FIELD_FL_STACKTRACE)) 4497 hist_data->fields[val_idx]->var_str_idx = hist_data->n_var_str++; 4498 4499 return ret; 4500 } 4501 4502 static int create_val_fields(struct hist_trigger_data *hist_data, 4503 struct trace_event_file *file) 4504 { 4505 unsigned int i, j = 1, n_hitcount = 0; 4506 char *fields_str, *field_str; 4507 int ret; 4508 4509 ret = create_hitcount_val(hist_data); 4510 if (ret) 4511 goto out; 4512 4513 fields_str = hist_data->attrs->vals_str; 4514 if (!fields_str) 4515 goto out; 4516 4517 for (i = 0, j = 1; i < TRACING_MAP_VALS_MAX && 4518 j < TRACING_MAP_VALS_MAX; i++) { 4519 field_str = strsep(&fields_str, ","); 4520 if (!field_str) 4521 break; 4522 4523 if (strcmp(field_str, "hitcount") == 0) { 4524 if (!n_hitcount++) 4525 continue; 4526 } 4527 4528 ret = create_val_field(hist_data, j++, file, field_str); 4529 if (ret) 4530 goto out; 4531 } 4532 4533 if (fields_str && (strcmp(fields_str, "hitcount") != 0)) 4534 ret = -EINVAL; 4535 out: 4536 /* There is only raw hitcount but nohitcount suppresses it. */ 4537 if (j == 1 && hist_data->attrs->no_hitcount) { 4538 hist_err(hist_data->event_file->tr, HIST_ERR_NEED_NOHC_VAL, 0); 4539 ret = -ENOENT; 4540 } 4541 4542 return ret; 4543 } 4544 4545 static int create_key_field(struct hist_trigger_data *hist_data, 4546 unsigned int key_idx, 4547 unsigned int key_offset, 4548 struct trace_event_file *file, 4549 char *field_str) 4550 { 4551 struct trace_array *tr = hist_data->event_file->tr; 4552 struct hist_field *hist_field = NULL; 4553 unsigned long flags = 0; 4554 unsigned int key_size; 4555 int ret = 0, n_subexprs = 0; 4556 4557 if (WARN_ON(key_idx >= HIST_FIELDS_MAX)) 4558 return -EINVAL; 4559 4560 flags |= HIST_FIELD_FL_KEY; 4561 4562 if (strcmp(field_str, "stacktrace") == 0) { 4563 flags |= HIST_FIELD_FL_STACKTRACE; 4564 key_size = sizeof(unsigned long) * HIST_STACKTRACE_DEPTH; 4565 hist_field = create_hist_field(hist_data, NULL, flags, NULL); 4566 } else { 4567 hist_field = parse_expr(hist_data, file, field_str, flags, 4568 NULL, &n_subexprs); 4569 if (IS_ERR(hist_field)) { 4570 ret = PTR_ERR(hist_field); 4571 goto out; 4572 } 4573 4574 if (field_has_hist_vars(hist_field, 0)) { 4575 hist_err(tr, HIST_ERR_INVALID_REF_KEY, errpos(field_str)); 4576 destroy_hist_field(hist_field, 0); 4577 ret = -EINVAL; 4578 goto out; 4579 } 4580 4581 key_size = hist_field->size; 4582 } 4583 4584 hist_data->fields[key_idx] = hist_field; 4585 4586 key_size = ALIGN(key_size, sizeof(u64)); 4587 hist_data->fields[key_idx]->size = key_size; 4588 hist_data->fields[key_idx]->offset = key_offset; 4589 4590 hist_data->key_size += key_size; 4591 4592 if (hist_data->key_size > HIST_KEY_SIZE_MAX) { 4593 ret = -EINVAL; 4594 goto out; 4595 } 4596 4597 hist_data->n_keys++; 4598 hist_data->n_fields++; 4599 4600 if (WARN_ON(hist_data->n_keys > TRACING_MAP_KEYS_MAX)) 4601 return -EINVAL; 4602 4603 ret = key_size; 4604 out: 4605 return ret; 4606 } 4607 4608 static int create_key_fields(struct hist_trigger_data *hist_data, 4609 struct trace_event_file *file) 4610 { 4611 unsigned int i, key_offset = 0, n_vals = hist_data->n_vals; 4612 char *fields_str, *field_str; 4613 int ret = -EINVAL; 4614 4615 fields_str = hist_data->attrs->keys_str; 4616 if (!fields_str) 4617 goto out; 4618 4619 for (i = n_vals; i < n_vals + TRACING_MAP_KEYS_MAX; i++) { 4620 field_str = strsep(&fields_str, ","); 4621 if (!field_str) 4622 break; 4623 ret = create_key_field(hist_data, i, key_offset, 4624 file, field_str); 4625 if (ret < 0) 4626 goto out; 4627 key_offset += ret; 4628 } 4629 if (fields_str) { 4630 ret = -EINVAL; 4631 goto out; 4632 } 4633 ret = 0; 4634 out: 4635 return ret; 4636 } 4637 4638 static int create_var_fields(struct hist_trigger_data *hist_data, 4639 struct trace_event_file *file) 4640 { 4641 unsigned int i, j = hist_data->n_vals; 4642 int ret = 0; 4643 4644 unsigned int n_vars = hist_data->attrs->var_defs.n_vars; 4645 4646 for (i = 0; i < n_vars; i++) { 4647 char *var_name = hist_data->attrs->var_defs.name[i]; 4648 char *expr = hist_data->attrs->var_defs.expr[i]; 4649 4650 ret = create_var_field(hist_data, j++, file, var_name, expr); 4651 if (ret) 4652 goto out; 4653 } 4654 out: 4655 return ret; 4656 } 4657 4658 static void free_var_defs(struct hist_trigger_data *hist_data) 4659 { 4660 unsigned int i; 4661 4662 for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) { 4663 kfree(hist_data->attrs->var_defs.name[i]); 4664 kfree(hist_data->attrs->var_defs.expr[i]); 4665 } 4666 4667 hist_data->attrs->var_defs.n_vars = 0; 4668 } 4669 4670 static int parse_var_defs(struct hist_trigger_data *hist_data) 4671 { 4672 struct trace_array *tr = hist_data->event_file->tr; 4673 char *s, *str, *var_name, *field_str; 4674 unsigned int i, j, n_vars = 0; 4675 int ret = 0; 4676 4677 for (i = 0; i < hist_data->attrs->n_assignments; i++) { 4678 str = hist_data->attrs->assignment_str[i]; 4679 for (j = 0; j < TRACING_MAP_VARS_MAX; j++) { 4680 field_str = strsep(&str, ","); 4681 if (!field_str) 4682 break; 4683 4684 var_name = strsep(&field_str, "="); 4685 if (!var_name || !field_str) { 4686 hist_err(tr, HIST_ERR_MALFORMED_ASSIGNMENT, 4687 errpos(var_name)); 4688 ret = -EINVAL; 4689 goto free; 4690 } 4691 4692 if (n_vars == TRACING_MAP_VARS_MAX) { 4693 hist_err(tr, HIST_ERR_TOO_MANY_VARS, errpos(var_name)); 4694 ret = -EINVAL; 4695 goto free; 4696 } 4697 4698 s = kstrdup(var_name, GFP_KERNEL); 4699 if (!s) { 4700 ret = -ENOMEM; 4701 goto free; 4702 } 4703 hist_data->attrs->var_defs.name[n_vars] = s; 4704 4705 s = kstrdup(field_str, GFP_KERNEL); 4706 if (!s) { 4707 kfree(hist_data->attrs->var_defs.name[n_vars]); 4708 hist_data->attrs->var_defs.name[n_vars] = NULL; 4709 ret = -ENOMEM; 4710 goto free; 4711 } 4712 hist_data->attrs->var_defs.expr[n_vars++] = s; 4713 4714 hist_data->attrs->var_defs.n_vars = n_vars; 4715 } 4716 } 4717 4718 return ret; 4719 free: 4720 free_var_defs(hist_data); 4721 4722 return ret; 4723 } 4724 4725 static int create_hist_fields(struct hist_trigger_data *hist_data, 4726 struct trace_event_file *file) 4727 { 4728 int ret; 4729 4730 ret = parse_var_defs(hist_data); 4731 if (ret) 4732 return ret; 4733 4734 ret = create_val_fields(hist_data, file); 4735 if (ret) 4736 goto out; 4737 4738 ret = create_var_fields(hist_data, file); 4739 if (ret) 4740 goto out; 4741 4742 ret = create_key_fields(hist_data, file); 4743 4744 out: 4745 free_var_defs(hist_data); 4746 4747 return ret; 4748 } 4749 4750 static int is_descending(struct trace_array *tr, const char *str) 4751 { 4752 if (!str) 4753 return 0; 4754 4755 if (strcmp(str, "descending") == 0) 4756 return 1; 4757 4758 if (strcmp(str, "ascending") == 0) 4759 return 0; 4760 4761 hist_err(tr, HIST_ERR_INVALID_SORT_MODIFIER, errpos((char *)str)); 4762 4763 return -EINVAL; 4764 } 4765 4766 static int create_sort_keys(struct hist_trigger_data *hist_data) 4767 { 4768 struct trace_array *tr = hist_data->event_file->tr; 4769 char *fields_str = hist_data->attrs->sort_key_str; 4770 struct tracing_map_sort_key *sort_key; 4771 int descending, ret = 0; 4772 unsigned int i, j, k; 4773 4774 hist_data->n_sort_keys = 1; /* we always have at least one, hitcount */ 4775 4776 if (!fields_str) 4777 goto out; 4778 4779 for (i = 0; i < TRACING_MAP_SORT_KEYS_MAX; i++) { 4780 struct hist_field *hist_field; 4781 char *field_str, *field_name; 4782 const char *test_name; 4783 4784 sort_key = &hist_data->sort_keys[i]; 4785 4786 field_str = strsep(&fields_str, ","); 4787 if (!field_str) 4788 break; 4789 4790 if (!*field_str) { 4791 ret = -EINVAL; 4792 hist_err(tr, HIST_ERR_EMPTY_SORT_FIELD, errpos("sort=")); 4793 break; 4794 } 4795 4796 if ((i == TRACING_MAP_SORT_KEYS_MAX - 1) && fields_str) { 4797 hist_err(tr, HIST_ERR_TOO_MANY_SORT_FIELDS, errpos("sort=")); 4798 ret = -EINVAL; 4799 break; 4800 } 4801 4802 field_name = strsep(&field_str, "."); 4803 if (!field_name || !*field_name) { 4804 ret = -EINVAL; 4805 hist_err(tr, HIST_ERR_EMPTY_SORT_FIELD, errpos("sort=")); 4806 break; 4807 } 4808 4809 if (strcmp(field_name, "hitcount") == 0) { 4810 descending = is_descending(tr, field_str); 4811 if (descending < 0) { 4812 ret = descending; 4813 break; 4814 } 4815 sort_key->descending = descending; 4816 continue; 4817 } 4818 4819 for (j = 1, k = 1; j < hist_data->n_fields; j++) { 4820 unsigned int idx; 4821 4822 hist_field = hist_data->fields[j]; 4823 if (hist_field->flags & HIST_FIELD_FL_VAR) 4824 continue; 4825 4826 idx = k++; 4827 4828 test_name = hist_field_name(hist_field, 0); 4829 4830 if (strcmp(field_name, test_name) == 0) { 4831 sort_key->field_idx = idx; 4832 descending = is_descending(tr, field_str); 4833 if (descending < 0) { 4834 ret = descending; 4835 goto out; 4836 } 4837 sort_key->descending = descending; 4838 break; 4839 } 4840 } 4841 if (j == hist_data->n_fields) { 4842 ret = -EINVAL; 4843 hist_err(tr, HIST_ERR_INVALID_SORT_FIELD, errpos(field_name)); 4844 break; 4845 } 4846 } 4847 4848 hist_data->n_sort_keys = i; 4849 out: 4850 return ret; 4851 } 4852 4853 static void destroy_actions(struct hist_trigger_data *hist_data) 4854 { 4855 unsigned int i; 4856 4857 for (i = 0; i < hist_data->n_actions; i++) { 4858 struct action_data *data = hist_data->actions[i]; 4859 4860 if (data->handler == HANDLER_ONMATCH) 4861 onmatch_destroy(data); 4862 else if (data->handler == HANDLER_ONMAX || 4863 data->handler == HANDLER_ONCHANGE) 4864 track_data_destroy(hist_data, data); 4865 else 4866 kfree(data); 4867 } 4868 } 4869 4870 static int parse_actions(struct hist_trigger_data *hist_data) 4871 { 4872 struct trace_array *tr = hist_data->event_file->tr; 4873 struct action_data *data; 4874 unsigned int i; 4875 int ret = 0; 4876 char *str; 4877 int len; 4878 4879 for (i = 0; i < hist_data->attrs->n_actions; i++) { 4880 enum handler_id hid = 0; 4881 char *action_str; 4882 4883 str = hist_data->attrs->action_str[i]; 4884 4885 if ((len = str_has_prefix(str, "onmatch("))) 4886 hid = HANDLER_ONMATCH; 4887 else if ((len = str_has_prefix(str, "onmax("))) 4888 hid = HANDLER_ONMAX; 4889 else if ((len = str_has_prefix(str, "onchange("))) 4890 hid = HANDLER_ONCHANGE; 4891 4892 action_str = str + len; 4893 4894 switch (hid) { 4895 case HANDLER_ONMATCH: 4896 data = onmatch_parse(tr, action_str); 4897 break; 4898 case HANDLER_ONMAX: 4899 case HANDLER_ONCHANGE: 4900 data = track_data_parse(hist_data, action_str, hid); 4901 break; 4902 default: 4903 data = ERR_PTR(-EINVAL); 4904 break; 4905 } 4906 4907 if (IS_ERR(data)) { 4908 ret = PTR_ERR(data); 4909 break; 4910 } 4911 4912 hist_data->actions[hist_data->n_actions++] = data; 4913 } 4914 4915 return ret; 4916 } 4917 4918 static int create_actions(struct hist_trigger_data *hist_data) 4919 { 4920 struct action_data *data; 4921 unsigned int i; 4922 int ret = 0; 4923 4924 for (i = 0; i < hist_data->attrs->n_actions; i++) { 4925 data = hist_data->actions[i]; 4926 4927 if (data->handler == HANDLER_ONMATCH) { 4928 ret = onmatch_create(hist_data, data); 4929 if (ret) 4930 break; 4931 } else if (data->handler == HANDLER_ONMAX || 4932 data->handler == HANDLER_ONCHANGE) { 4933 ret = track_data_create(hist_data, data); 4934 if (ret) 4935 break; 4936 } else { 4937 ret = -EINVAL; 4938 break; 4939 } 4940 } 4941 4942 return ret; 4943 } 4944 4945 static void print_actions(struct seq_file *m, 4946 struct hist_trigger_data *hist_data, 4947 struct tracing_map_elt *elt) 4948 { 4949 unsigned int i; 4950 4951 for (i = 0; i < hist_data->n_actions; i++) { 4952 struct action_data *data = hist_data->actions[i]; 4953 4954 if (data->action == ACTION_SNAPSHOT) 4955 continue; 4956 4957 if (data->handler == HANDLER_ONMAX || 4958 data->handler == HANDLER_ONCHANGE) 4959 track_data_print(m, hist_data, elt, data); 4960 } 4961 } 4962 4963 static void print_action_spec(struct seq_file *m, 4964 struct hist_trigger_data *hist_data, 4965 struct action_data *data) 4966 { 4967 unsigned int i; 4968 4969 if (data->action == ACTION_SAVE) { 4970 for (i = 0; i < hist_data->n_save_vars; i++) { 4971 seq_printf(m, "%s", hist_data->save_vars[i]->var->var.name); 4972 if (i < hist_data->n_save_vars - 1) 4973 seq_puts(m, ","); 4974 } 4975 } else if (data->action == ACTION_TRACE) { 4976 if (data->use_trace_keyword) 4977 seq_printf(m, "%s", data->synth_event_name); 4978 for (i = 0; i < data->n_params; i++) { 4979 if (i || data->use_trace_keyword) 4980 seq_puts(m, ","); 4981 seq_printf(m, "%s", data->params[i]); 4982 } 4983 } 4984 } 4985 4986 static void print_track_data_spec(struct seq_file *m, 4987 struct hist_trigger_data *hist_data, 4988 struct action_data *data) 4989 { 4990 if (data->handler == HANDLER_ONMAX) 4991 seq_puts(m, ":onmax("); 4992 else if (data->handler == HANDLER_ONCHANGE) 4993 seq_puts(m, ":onchange("); 4994 seq_printf(m, "%s", data->track_data.var_str); 4995 seq_printf(m, ").%s(", data->action_name); 4996 4997 print_action_spec(m, hist_data, data); 4998 4999 seq_puts(m, ")"); 5000 } 5001 5002 static void print_onmatch_spec(struct seq_file *m, 5003 struct hist_trigger_data *hist_data, 5004 struct action_data *data) 5005 { 5006 seq_printf(m, ":onmatch(%s.%s).", data->match_data.event_system, 5007 data->match_data.event); 5008 5009 seq_printf(m, "%s(", data->action_name); 5010 5011 print_action_spec(m, hist_data, data); 5012 5013 seq_puts(m, ")"); 5014 } 5015 5016 static bool actions_match(struct hist_trigger_data *hist_data, 5017 struct hist_trigger_data *hist_data_test) 5018 { 5019 unsigned int i, j; 5020 5021 if (hist_data->n_actions != hist_data_test->n_actions) 5022 return false; 5023 5024 for (i = 0; i < hist_data->n_actions; i++) { 5025 struct action_data *data = hist_data->actions[i]; 5026 struct action_data *data_test = hist_data_test->actions[i]; 5027 char *action_name, *action_name_test; 5028 5029 if (data->handler != data_test->handler) 5030 return false; 5031 if (data->action != data_test->action) 5032 return false; 5033 5034 if (data->n_params != data_test->n_params) 5035 return false; 5036 5037 for (j = 0; j < data->n_params; j++) { 5038 if (strcmp(data->params[j], data_test->params[j]) != 0) 5039 return false; 5040 } 5041 5042 if (data->use_trace_keyword) 5043 action_name = data->synth_event_name; 5044 else 5045 action_name = data->action_name; 5046 5047 if (data_test->use_trace_keyword) 5048 action_name_test = data_test->synth_event_name; 5049 else 5050 action_name_test = data_test->action_name; 5051 5052 if (strcmp(action_name, action_name_test) != 0) 5053 return false; 5054 5055 if (data->handler == HANDLER_ONMATCH) { 5056 if (strcmp(data->match_data.event_system, 5057 data_test->match_data.event_system) != 0) 5058 return false; 5059 if (strcmp(data->match_data.event, 5060 data_test->match_data.event) != 0) 5061 return false; 5062 } else if (data->handler == HANDLER_ONMAX || 5063 data->handler == HANDLER_ONCHANGE) { 5064 if (strcmp(data->track_data.var_str, 5065 data_test->track_data.var_str) != 0) 5066 return false; 5067 } 5068 } 5069 5070 return true; 5071 } 5072 5073 5074 static void print_actions_spec(struct seq_file *m, 5075 struct hist_trigger_data *hist_data) 5076 { 5077 unsigned int i; 5078 5079 for (i = 0; i < hist_data->n_actions; i++) { 5080 struct action_data *data = hist_data->actions[i]; 5081 5082 if (data->handler == HANDLER_ONMATCH) 5083 print_onmatch_spec(m, hist_data, data); 5084 else if (data->handler == HANDLER_ONMAX || 5085 data->handler == HANDLER_ONCHANGE) 5086 print_track_data_spec(m, hist_data, data); 5087 } 5088 } 5089 5090 static void destroy_field_var_hists(struct hist_trigger_data *hist_data) 5091 { 5092 unsigned int i; 5093 5094 for (i = 0; i < hist_data->n_field_var_hists; i++) { 5095 kfree(hist_data->field_var_hists[i]->cmd); 5096 kfree(hist_data->field_var_hists[i]); 5097 } 5098 } 5099 5100 static void destroy_hist_data(struct hist_trigger_data *hist_data) 5101 { 5102 if (!hist_data) 5103 return; 5104 5105 destroy_hist_trigger_attrs(hist_data->attrs); 5106 destroy_hist_fields(hist_data); 5107 tracing_map_destroy(hist_data->map); 5108 5109 destroy_actions(hist_data); 5110 destroy_field_vars(hist_data); 5111 destroy_field_var_hists(hist_data); 5112 5113 kfree(hist_data); 5114 } 5115 5116 static int create_tracing_map_fields(struct hist_trigger_data *hist_data) 5117 { 5118 struct tracing_map *map = hist_data->map; 5119 struct ftrace_event_field *field; 5120 struct hist_field *hist_field; 5121 int i, idx = 0; 5122 5123 for_each_hist_field(i, hist_data) { 5124 hist_field = hist_data->fields[i]; 5125 if (hist_field->flags & HIST_FIELD_FL_KEY) { 5126 tracing_map_cmp_fn_t cmp_fn; 5127 5128 field = hist_field->field; 5129 5130 if (hist_field->flags & HIST_FIELD_FL_STACKTRACE) 5131 cmp_fn = tracing_map_cmp_none; 5132 else if (!field || hist_field->flags & HIST_FIELD_FL_CPU) 5133 cmp_fn = tracing_map_cmp_num(hist_field->size, 5134 hist_field->is_signed); 5135 else if (is_string_field(field)) 5136 cmp_fn = tracing_map_cmp_string; 5137 else 5138 cmp_fn = tracing_map_cmp_num(field->size, 5139 field->is_signed); 5140 idx = tracing_map_add_key_field(map, 5141 hist_field->offset, 5142 cmp_fn); 5143 } else if (!(hist_field->flags & HIST_FIELD_FL_VAR)) 5144 idx = tracing_map_add_sum_field(map); 5145 5146 if (idx < 0) 5147 return idx; 5148 5149 if (hist_field->flags & HIST_FIELD_FL_VAR) { 5150 idx = tracing_map_add_var(map); 5151 if (idx < 0) 5152 return idx; 5153 hist_field->var.idx = idx; 5154 hist_field->var.hist_data = hist_data; 5155 } 5156 } 5157 5158 return 0; 5159 } 5160 5161 static struct hist_trigger_data * 5162 create_hist_data(unsigned int map_bits, 5163 struct hist_trigger_attrs *attrs, 5164 struct trace_event_file *file, 5165 bool remove) 5166 { 5167 const struct tracing_map_ops *map_ops = NULL; 5168 struct hist_trigger_data *hist_data; 5169 int ret = 0; 5170 5171 hist_data = kzalloc_obj(*hist_data); 5172 if (!hist_data) 5173 return ERR_PTR(-ENOMEM); 5174 5175 hist_data->attrs = attrs; 5176 hist_data->remove = remove; 5177 hist_data->event_file = file; 5178 5179 ret = parse_actions(hist_data); 5180 if (ret) 5181 goto free; 5182 5183 ret = create_hist_fields(hist_data, file); 5184 if (ret) 5185 goto free; 5186 5187 ret = create_sort_keys(hist_data); 5188 if (ret) 5189 goto free; 5190 5191 map_ops = &hist_trigger_elt_data_ops; 5192 5193 hist_data->map = tracing_map_create(map_bits, hist_data->key_size, 5194 map_ops, hist_data); 5195 if (IS_ERR(hist_data->map)) { 5196 ret = PTR_ERR(hist_data->map); 5197 hist_data->map = NULL; 5198 goto free; 5199 } 5200 5201 ret = create_tracing_map_fields(hist_data); 5202 if (ret) 5203 goto free; 5204 out: 5205 return hist_data; 5206 free: 5207 hist_data->attrs = NULL; 5208 5209 destroy_hist_data(hist_data); 5210 5211 hist_data = ERR_PTR(ret); 5212 5213 goto out; 5214 } 5215 5216 static void hist_trigger_elt_update(struct hist_trigger_data *hist_data, 5217 struct tracing_map_elt *elt, 5218 struct trace_buffer *buffer, void *rec, 5219 struct ring_buffer_event *rbe, 5220 u64 *var_ref_vals) 5221 { 5222 struct hist_elt_data *elt_data; 5223 struct hist_field *hist_field; 5224 unsigned int i, var_idx; 5225 u64 hist_val; 5226 5227 elt_data = elt->private_data; 5228 elt_data->var_ref_vals = var_ref_vals; 5229 5230 for_each_hist_val_field(i, hist_data) { 5231 hist_field = hist_data->fields[i]; 5232 hist_val = hist_fn_call(hist_field, elt, buffer, rbe, rec); 5233 if (hist_field->flags & HIST_FIELD_FL_VAR) { 5234 var_idx = hist_field->var.idx; 5235 5236 if (hist_field->flags & 5237 (HIST_FIELD_FL_STRING | HIST_FIELD_FL_STACKTRACE)) { 5238 unsigned int str_start, var_str_idx, idx; 5239 char *str, *val_str; 5240 unsigned int size; 5241 5242 str_start = hist_data->n_field_var_str + 5243 hist_data->n_save_var_str; 5244 var_str_idx = hist_field->var_str_idx; 5245 idx = str_start + var_str_idx; 5246 5247 str = elt_data->field_var_str[idx]; 5248 val_str = (char *)(uintptr_t)hist_val; 5249 5250 if (hist_field->flags & HIST_FIELD_FL_STRING) { 5251 size = min(hist_field->size, STR_VAR_LEN_MAX); 5252 strscpy(str, val_str, size); 5253 } else { 5254 char *stack_start = str + sizeof(unsigned long); 5255 int e; 5256 5257 e = stack_trace_save((void *)stack_start, 5258 HIST_STACKTRACE_DEPTH, 5259 HIST_STACKTRACE_SKIP); 5260 if (e < HIST_STACKTRACE_DEPTH - 1) 5261 ((unsigned long *)stack_start)[e] = 0; 5262 *((unsigned long *)str) = e; 5263 } 5264 hist_val = (u64)(uintptr_t)str; 5265 } 5266 tracing_map_set_var(elt, var_idx, hist_val); 5267 continue; 5268 } 5269 tracing_map_update_sum(elt, i, hist_val); 5270 } 5271 5272 for_each_hist_key_field(i, hist_data) { 5273 hist_field = hist_data->fields[i]; 5274 if (hist_field->flags & HIST_FIELD_FL_VAR) { 5275 hist_val = hist_fn_call(hist_field, elt, buffer, rbe, rec); 5276 var_idx = hist_field->var.idx; 5277 tracing_map_set_var(elt, var_idx, hist_val); 5278 } 5279 } 5280 5281 update_field_vars(hist_data, elt, buffer, rbe, rec); 5282 } 5283 5284 static inline void add_to_key(char *compound_key, void *key, 5285 struct hist_field *key_field, void *rec) 5286 { 5287 size_t size = key_field->size; 5288 5289 if (key_field->flags & HIST_FIELD_FL_STRING) { 5290 5291 if (key_field->flags & HIST_FIELD_FL_COMM) { 5292 size = strlen((char *)key); 5293 } else { 5294 struct ftrace_event_field *field; 5295 5296 field = key_field->field; 5297 if (field->filter_type == FILTER_DYN_STRING || 5298 field->filter_type == FILTER_RDYN_STRING) 5299 size = *(u32 *)(rec + field->offset) >> 16; 5300 else if (field->filter_type == FILTER_STATIC_STRING) 5301 size = field->size; 5302 } 5303 5304 /* ensure NULL-termination */ 5305 if (size > key_field->size - 1) 5306 size = key_field->size - 1; 5307 } 5308 memcpy(compound_key + key_field->offset, key, size); 5309 } 5310 5311 static void 5312 hist_trigger_actions(struct hist_trigger_data *hist_data, 5313 struct tracing_map_elt *elt, 5314 struct trace_buffer *buffer, void *rec, 5315 struct ring_buffer_event *rbe, void *key, 5316 u64 *var_ref_vals) 5317 { 5318 struct action_data *data; 5319 unsigned int i; 5320 5321 for (i = 0; i < hist_data->n_actions; i++) { 5322 data = hist_data->actions[i]; 5323 data->fn(hist_data, elt, buffer, rec, rbe, key, data, var_ref_vals); 5324 } 5325 } 5326 5327 /* 5328 * The hist_pad structure is used to save information to create 5329 * a histogram from the histogram trigger. It's too big to store 5330 * on the stack, so when the histogram trigger is initialized 5331 * a percpu array of 4 hist_pad structures is allocated. 5332 * This will cover every context from normal, softirq, irq and NMI 5333 * in the very unlikely event that a trigger happens at each of 5334 * these contexts and interrupts a currently active trigger. 5335 */ 5336 struct hist_pad { 5337 unsigned long entries[HIST_STACKTRACE_DEPTH]; 5338 u64 var_ref_vals[TRACING_MAP_VARS_MAX]; 5339 char compound_key[HIST_KEY_SIZE_MAX]; 5340 }; 5341 5342 static struct hist_pad __percpu *hist_pads; 5343 static DEFINE_PER_CPU(int, hist_pad_cnt); 5344 static refcount_t hist_pad_ref; 5345 5346 /* One hist_pad for every context (normal, softirq, irq, NMI) */ 5347 #define MAX_HIST_CNT 4 5348 5349 static int alloc_hist_pad(void) 5350 { 5351 lockdep_assert_held(&event_mutex); 5352 5353 if (refcount_read(&hist_pad_ref)) { 5354 refcount_inc(&hist_pad_ref); 5355 return 0; 5356 } 5357 5358 hist_pads = __alloc_percpu(sizeof(struct hist_pad) * MAX_HIST_CNT, 5359 __alignof__(struct hist_pad)); 5360 if (!hist_pads) 5361 return -ENOMEM; 5362 5363 refcount_set(&hist_pad_ref, 1); 5364 return 0; 5365 } 5366 5367 static void free_hist_pad(void) 5368 { 5369 lockdep_assert_held(&event_mutex); 5370 5371 if (!refcount_dec_and_test(&hist_pad_ref)) 5372 return; 5373 5374 free_percpu(hist_pads); 5375 hist_pads = NULL; 5376 } 5377 5378 static struct hist_pad *get_hist_pad(void) 5379 { 5380 struct hist_pad *hist_pad; 5381 int cnt; 5382 5383 if (WARN_ON_ONCE(!hist_pads)) 5384 return NULL; 5385 5386 preempt_disable(); 5387 5388 hist_pad = per_cpu_ptr(hist_pads, smp_processor_id()); 5389 5390 if (this_cpu_read(hist_pad_cnt) == MAX_HIST_CNT) { 5391 preempt_enable(); 5392 return NULL; 5393 } 5394 5395 cnt = this_cpu_inc_return(hist_pad_cnt) - 1; 5396 5397 return &hist_pad[cnt]; 5398 } 5399 5400 static void put_hist_pad(void) 5401 { 5402 this_cpu_dec(hist_pad_cnt); 5403 preempt_enable(); 5404 } 5405 5406 static void event_hist_trigger(struct event_trigger_data *data, 5407 struct trace_buffer *buffer, void *rec, 5408 struct ring_buffer_event *rbe) 5409 { 5410 struct hist_trigger_data *hist_data = data->private_data; 5411 bool use_compound_key = (hist_data->n_keys > 1); 5412 struct tracing_map_elt *elt = NULL; 5413 struct hist_field *key_field; 5414 struct hist_pad *hist_pad; 5415 u64 field_contents; 5416 void *key = NULL; 5417 unsigned int i; 5418 5419 if (unlikely(!rbe)) 5420 return; 5421 5422 hist_pad = get_hist_pad(); 5423 if (!hist_pad) 5424 return; 5425 5426 memset(hist_pad->compound_key, 0, hist_data->key_size); 5427 5428 for_each_hist_key_field(i, hist_data) { 5429 key_field = hist_data->fields[i]; 5430 5431 if (key_field->flags & HIST_FIELD_FL_STACKTRACE) { 5432 unsigned long *entries = hist_pad->entries; 5433 5434 memset(entries, 0, HIST_STACKTRACE_SIZE); 5435 if (key_field->field) { 5436 unsigned long *stack, n_entries; 5437 5438 field_contents = hist_fn_call(key_field, elt, buffer, rbe, rec); 5439 stack = (unsigned long *)(long)field_contents; 5440 n_entries = *stack; 5441 memcpy(entries, ++stack, n_entries * sizeof(unsigned long)); 5442 } else { 5443 stack_trace_save(entries, HIST_STACKTRACE_DEPTH, 5444 HIST_STACKTRACE_SKIP); 5445 } 5446 key = entries; 5447 } else { 5448 field_contents = hist_fn_call(key_field, elt, buffer, rbe, rec); 5449 if (key_field->flags & HIST_FIELD_FL_STRING) { 5450 key = (void *)(unsigned long)field_contents; 5451 use_compound_key = true; 5452 } else 5453 key = (void *)&field_contents; 5454 } 5455 5456 if (use_compound_key) 5457 add_to_key(hist_pad->compound_key, key, key_field, rec); 5458 } 5459 5460 if (use_compound_key) 5461 key = hist_pad->compound_key; 5462 5463 if (hist_data->n_var_refs && 5464 !resolve_var_refs(hist_data, key, hist_pad->var_ref_vals, false)) 5465 goto out; 5466 5467 elt = tracing_map_insert(hist_data->map, key); 5468 if (!elt) 5469 goto out; 5470 5471 hist_trigger_elt_update(hist_data, elt, buffer, rec, rbe, hist_pad->var_ref_vals); 5472 5473 if (resolve_var_refs(hist_data, key, hist_pad->var_ref_vals, true)) { 5474 hist_trigger_actions(hist_data, elt, buffer, rec, rbe, 5475 key, hist_pad->var_ref_vals); 5476 } 5477 5478 hist_poll_wakeup(); 5479 5480 out: 5481 put_hist_pad(); 5482 } 5483 5484 static void hist_trigger_stacktrace_print(struct seq_file *m, 5485 unsigned long *stacktrace_entries, 5486 unsigned int max_entries) 5487 { 5488 unsigned int spaces = 8; 5489 unsigned int i; 5490 5491 for (i = 0; i < max_entries; i++) { 5492 if (!stacktrace_entries[i]) 5493 return; 5494 5495 seq_printf(m, "%*c", 1 + spaces, ' '); 5496 seq_printf(m, "%pS\n", (void*)stacktrace_entries[i]); 5497 } 5498 } 5499 5500 static void hist_trigger_print_key(struct seq_file *m, 5501 struct hist_trigger_data *hist_data, 5502 void *key, 5503 struct tracing_map_elt *elt) 5504 { 5505 struct hist_field *key_field; 5506 bool multiline = false; 5507 const char *field_name; 5508 unsigned int i; 5509 u64 uval; 5510 5511 seq_puts(m, "{ "); 5512 5513 for_each_hist_key_field(i, hist_data) { 5514 key_field = hist_data->fields[i]; 5515 5516 if (i > hist_data->n_vals) 5517 seq_puts(m, ", "); 5518 5519 field_name = hist_field_name(key_field, 0); 5520 5521 if (key_field->flags & HIST_FIELD_FL_HEX) { 5522 uval = *(u64 *)(key + key_field->offset); 5523 seq_printf(m, "%s: %llx", field_name, uval); 5524 } else if (key_field->flags & HIST_FIELD_FL_SYM) { 5525 uval = *(u64 *)(key + key_field->offset); 5526 seq_printf(m, "%s: [%llx] %-45ps", field_name, 5527 uval, (void *)(uintptr_t)uval); 5528 } else if (key_field->flags & HIST_FIELD_FL_SYM_OFFSET) { 5529 uval = *(u64 *)(key + key_field->offset); 5530 seq_printf(m, "%s: [%llx] %-55pS", field_name, 5531 uval, (void *)(uintptr_t)uval); 5532 } else if (key_field->flags & HIST_FIELD_FL_EXECNAME) { 5533 struct hist_elt_data *elt_data = elt->private_data; 5534 char *comm; 5535 5536 if (WARN_ON_ONCE(!elt_data)) 5537 return; 5538 5539 comm = elt_data->comm; 5540 5541 uval = *(u64 *)(key + key_field->offset); 5542 seq_printf(m, "%s: %-16s[%10llu]", field_name, 5543 comm, uval); 5544 } else if (key_field->flags & HIST_FIELD_FL_SYSCALL) { 5545 const char *syscall_name; 5546 5547 uval = *(u64 *)(key + key_field->offset); 5548 syscall_name = get_syscall_name(uval); 5549 if (!syscall_name) 5550 syscall_name = "unknown_syscall"; 5551 5552 seq_printf(m, "%s: %-30s[%3llu]", field_name, 5553 syscall_name, uval); 5554 } else if (key_field->flags & HIST_FIELD_FL_STACKTRACE) { 5555 if (key_field->field) 5556 seq_printf(m, "%s.stacktrace", key_field->field->name); 5557 else 5558 seq_puts(m, "common_stacktrace:\n"); 5559 hist_trigger_stacktrace_print(m, 5560 key + key_field->offset, 5561 HIST_STACKTRACE_DEPTH); 5562 multiline = true; 5563 } else if (key_field->flags & HIST_FIELD_FL_LOG2) { 5564 seq_printf(m, "%s: ~ 2^%-2llu", field_name, 5565 *(u64 *)(key + key_field->offset)); 5566 } else if (key_field->flags & HIST_FIELD_FL_BUCKET) { 5567 unsigned long buckets = key_field->buckets; 5568 uval = *(u64 *)(key + key_field->offset); 5569 seq_printf(m, "%s: ~ %llu-%llu", field_name, 5570 uval, uval + buckets -1); 5571 } else if (key_field->flags & HIST_FIELD_FL_STRING) { 5572 seq_printf(m, "%s: %-50s", field_name, 5573 (char *)(key + key_field->offset)); 5574 } else { 5575 uval = *(u64 *)(key + key_field->offset); 5576 seq_printf(m, "%s: %10llu", field_name, uval); 5577 } 5578 } 5579 5580 if (!multiline) 5581 seq_puts(m, " "); 5582 5583 seq_puts(m, "}"); 5584 } 5585 5586 /* Get the 100 times of the percentage of @val in @total */ 5587 static inline unsigned int __get_percentage(u64 val, u64 total) 5588 { 5589 if (!total) 5590 goto div0; 5591 5592 if (val < (U64_MAX / 10000)) 5593 return (unsigned int)div64_ul(val * 10000, total); 5594 5595 total = div64_u64(total, 10000); 5596 if (!total) 5597 goto div0; 5598 5599 return (unsigned int)div64_ul(val, total); 5600 div0: 5601 return val ? UINT_MAX : 0; 5602 } 5603 5604 #define BAR_CHAR '#' 5605 5606 static inline const char *__fill_bar_str(char *buf, int size, u64 val, u64 max) 5607 { 5608 unsigned int len = __get_percentage(val, max); 5609 int i; 5610 5611 if (len == UINT_MAX) { 5612 snprintf(buf, size, "[ERROR]"); 5613 return buf; 5614 } 5615 5616 len = len * size / 10000; 5617 for (i = 0; i < len && i < size; i++) 5618 buf[i] = BAR_CHAR; 5619 while (i < size) 5620 buf[i++] = ' '; 5621 buf[size] = '\0'; 5622 5623 return buf; 5624 } 5625 5626 struct hist_val_stat { 5627 u64 max; 5628 u64 total; 5629 }; 5630 5631 static void hist_trigger_print_val(struct seq_file *m, unsigned int idx, 5632 const char *field_name, unsigned long flags, 5633 struct hist_val_stat *stats, 5634 struct tracing_map_elt *elt) 5635 { 5636 u64 val = tracing_map_read_sum(elt, idx); 5637 unsigned int pc; 5638 char bar[21]; 5639 5640 if (flags & HIST_FIELD_FL_PERCENT) { 5641 pc = __get_percentage(val, stats[idx].total); 5642 if (pc == UINT_MAX) 5643 seq_printf(m, " %s (%%):[ERROR]", field_name); 5644 else 5645 seq_printf(m, " %s (%%): %3u.%02u", field_name, 5646 pc / 100, pc % 100); 5647 } else if (flags & HIST_FIELD_FL_GRAPH) { 5648 seq_printf(m, " %s: %20s", field_name, 5649 __fill_bar_str(bar, 20, val, stats[idx].max)); 5650 } else if (flags & HIST_FIELD_FL_HEX) { 5651 seq_printf(m, " %s: %10llx", field_name, val); 5652 } else { 5653 seq_printf(m, " %s: %10llu", field_name, val); 5654 } 5655 } 5656 5657 static void hist_trigger_entry_print(struct seq_file *m, 5658 struct hist_trigger_data *hist_data, 5659 struct hist_val_stat *stats, 5660 void *key, 5661 struct tracing_map_elt *elt) 5662 { 5663 const char *field_name; 5664 unsigned int i = HITCOUNT_IDX; 5665 unsigned long flags; 5666 5667 hist_trigger_print_key(m, hist_data, key, elt); 5668 5669 /* At first, show the raw hitcount if !nohitcount */ 5670 if (!hist_data->attrs->no_hitcount) 5671 hist_trigger_print_val(m, i, "hitcount", 0, stats, elt); 5672 5673 for (i = 1; i < hist_data->n_vals; i++) { 5674 field_name = hist_field_name(hist_data->fields[i], 0); 5675 flags = hist_data->fields[i]->flags; 5676 if (flags & HIST_FIELD_FL_VAR || flags & HIST_FIELD_FL_EXPR) 5677 continue; 5678 5679 seq_puts(m, " "); 5680 hist_trigger_print_val(m, i, field_name, flags, stats, elt); 5681 } 5682 5683 print_actions(m, hist_data, elt); 5684 5685 seq_puts(m, "\n"); 5686 } 5687 5688 static int print_entries(struct seq_file *m, 5689 struct hist_trigger_data *hist_data) 5690 { 5691 struct tracing_map_sort_entry **sort_entries = NULL; 5692 struct tracing_map *map = hist_data->map; 5693 int i, j, n_entries; 5694 struct hist_val_stat *stats = NULL; 5695 u64 val; 5696 5697 n_entries = tracing_map_sort_entries(map, hist_data->sort_keys, 5698 hist_data->n_sort_keys, 5699 &sort_entries); 5700 if (n_entries < 0) 5701 return n_entries; 5702 5703 /* Calculate the max and the total for each field if needed. */ 5704 for (j = 0; j < hist_data->n_vals; j++) { 5705 if (!(hist_data->fields[j]->flags & 5706 (HIST_FIELD_FL_PERCENT | HIST_FIELD_FL_GRAPH))) 5707 continue; 5708 if (!stats) { 5709 stats = kzalloc_objs(*stats, hist_data->n_vals); 5710 if (!stats) { 5711 n_entries = -ENOMEM; 5712 goto out; 5713 } 5714 } 5715 for (i = 0; i < n_entries; i++) { 5716 val = tracing_map_read_sum(sort_entries[i]->elt, j); 5717 stats[j].total += val; 5718 if (stats[j].max < val) 5719 stats[j].max = val; 5720 } 5721 } 5722 5723 for (i = 0; i < n_entries; i++) 5724 hist_trigger_entry_print(m, hist_data, stats, 5725 sort_entries[i]->key, 5726 sort_entries[i]->elt); 5727 5728 kfree(stats); 5729 out: 5730 tracing_map_destroy_sort_entries(sort_entries, n_entries); 5731 5732 return n_entries; 5733 } 5734 5735 static void hist_trigger_show(struct seq_file *m, 5736 struct event_trigger_data *data, int n) 5737 { 5738 struct hist_trigger_data *hist_data; 5739 int n_entries; 5740 5741 if (n > 0) 5742 seq_puts(m, "\n\n"); 5743 5744 seq_puts(m, "# event histogram\n#\n# trigger info: "); 5745 data->cmd_ops->print(m, data); 5746 seq_puts(m, "#\n\n"); 5747 5748 hist_data = data->private_data; 5749 n_entries = print_entries(m, hist_data); 5750 if (n_entries < 0) 5751 n_entries = 0; 5752 5753 track_data_snapshot_print(m, hist_data); 5754 5755 seq_printf(m, "\nTotals:\n Hits: %llu\n Entries: %u\n Dropped: %llu\n", 5756 (u64)atomic64_read(&hist_data->map->hits), 5757 n_entries, (u64)atomic64_read(&hist_data->map->drops)); 5758 } 5759 5760 struct hist_file_data { 5761 struct file *file; 5762 u64 last_read; 5763 u64 last_act; 5764 }; 5765 5766 static u64 get_hist_hit_count(struct trace_event_file *event_file) 5767 { 5768 struct hist_trigger_data *hist_data; 5769 struct event_trigger_data *data; 5770 u64 ret = 0; 5771 5772 list_for_each_entry(data, &event_file->triggers, list) { 5773 if (data->cmd_ops->trigger_type == ETT_EVENT_HIST) { 5774 hist_data = data->private_data; 5775 ret += atomic64_read(&hist_data->map->hits); 5776 } 5777 } 5778 return ret; 5779 } 5780 5781 static int hist_show(struct seq_file *m, void *v) 5782 { 5783 struct hist_file_data *hist_file = m->private; 5784 struct event_trigger_data *data; 5785 struct trace_event_file *event_file; 5786 int n = 0; 5787 5788 guard(mutex)(&event_mutex); 5789 5790 event_file = event_file_file(hist_file->file); 5791 if (unlikely(!event_file)) 5792 return -ENODEV; 5793 5794 list_for_each_entry(data, &event_file->triggers, list) { 5795 if (data->cmd_ops->trigger_type == ETT_EVENT_HIST) 5796 hist_trigger_show(m, data, n++); 5797 } 5798 hist_file->last_read = get_hist_hit_count(event_file); 5799 /* 5800 * Update last_act too so that poll()/POLLPRI can wait for the next 5801 * event after any syscall on hist file. 5802 */ 5803 hist_file->last_act = hist_file->last_read; 5804 5805 return 0; 5806 } 5807 5808 static __poll_t event_hist_poll(struct file *file, struct poll_table_struct *wait) 5809 { 5810 struct trace_event_file *event_file; 5811 struct seq_file *m = file->private_data; 5812 struct hist_file_data *hist_file = m->private; 5813 __poll_t ret = 0; 5814 u64 cnt; 5815 5816 guard(mutex)(&event_mutex); 5817 5818 event_file = event_file_file(file); 5819 if (!event_file) 5820 return EPOLLERR; 5821 5822 hist_poll_wait(file, wait); 5823 5824 cnt = get_hist_hit_count(event_file); 5825 if (hist_file->last_read != cnt) 5826 ret |= EPOLLIN | EPOLLRDNORM; 5827 if (hist_file->last_act != cnt) { 5828 hist_file->last_act = cnt; 5829 ret |= EPOLLPRI; 5830 } 5831 5832 return ret; 5833 } 5834 5835 static int event_hist_release(struct inode *inode, struct file *file) 5836 { 5837 struct seq_file *m = file->private_data; 5838 struct hist_file_data *hist_file = m->private; 5839 5840 kfree(hist_file); 5841 return tracing_single_release_file_tr(inode, file); 5842 } 5843 5844 static int event_hist_open(struct inode *inode, struct file *file) 5845 { 5846 struct trace_event_file *event_file; 5847 struct hist_file_data *hist_file; 5848 int ret; 5849 5850 ret = tracing_open_file_tr(inode, file); 5851 if (ret) 5852 return ret; 5853 5854 guard(mutex)(&event_mutex); 5855 5856 event_file = event_file_file(file); 5857 if (!event_file) { 5858 ret = -ENODEV; 5859 goto err; 5860 } 5861 5862 hist_file = kzalloc_obj(*hist_file); 5863 if (!hist_file) { 5864 ret = -ENOMEM; 5865 goto err; 5866 } 5867 5868 hist_file->file = file; 5869 hist_file->last_act = get_hist_hit_count(event_file); 5870 5871 ret = single_open(file, hist_show, hist_file); 5872 if (ret) { 5873 kfree(hist_file); 5874 goto err; 5875 } 5876 5877 return 0; 5878 err: 5879 tracing_release_file_tr(inode, file); 5880 return ret; 5881 } 5882 5883 const struct file_operations event_hist_fops = { 5884 .open = event_hist_open, 5885 .read = seq_read, 5886 .llseek = seq_lseek, 5887 .release = event_hist_release, 5888 .poll = event_hist_poll, 5889 }; 5890 5891 #ifdef CONFIG_HIST_TRIGGERS_DEBUG 5892 5893 #undef C 5894 #define C(a, b) b 5895 5896 static const char * const field_funcs[] = { FIELD_FUNCS }; 5897 5898 static void hist_field_debug_show_flags(struct seq_file *m, 5899 unsigned long flags) 5900 { 5901 seq_puts(m, " flags:\n"); 5902 5903 if (flags & HIST_FIELD_FL_KEY) 5904 seq_puts(m, " HIST_FIELD_FL_KEY\n"); 5905 else if (flags & HIST_FIELD_FL_HITCOUNT) 5906 seq_puts(m, " VAL: HIST_FIELD_FL_HITCOUNT\n"); 5907 else if (flags & HIST_FIELD_FL_VAR) 5908 seq_puts(m, " HIST_FIELD_FL_VAR\n"); 5909 else if (flags & HIST_FIELD_FL_VAR_REF) 5910 seq_puts(m, " HIST_FIELD_FL_VAR_REF\n"); 5911 else 5912 seq_puts(m, " VAL: normal u64 value\n"); 5913 5914 if (flags & HIST_FIELD_FL_ALIAS) 5915 seq_puts(m, " HIST_FIELD_FL_ALIAS\n"); 5916 else if (flags & HIST_FIELD_FL_CONST) 5917 seq_puts(m, " HIST_FIELD_FL_CONST\n"); 5918 } 5919 5920 static int hist_field_debug_show(struct seq_file *m, 5921 struct hist_field *field, unsigned long flags) 5922 { 5923 if ((field->flags & flags) != flags) { 5924 seq_printf(m, "ERROR: bad flags - %lx\n", flags); 5925 return -EINVAL; 5926 } 5927 5928 hist_field_debug_show_flags(m, field->flags); 5929 if (field->field) 5930 seq_printf(m, " ftrace_event_field name: %s\n", 5931 field->field->name); 5932 5933 if (field->flags & HIST_FIELD_FL_VAR) { 5934 seq_printf(m, " var.name: %s\n", field->var.name); 5935 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n", 5936 field->var.idx); 5937 } 5938 5939 if (field->flags & HIST_FIELD_FL_CONST) 5940 seq_printf(m, " constant: %llu\n", field->constant); 5941 5942 if (field->flags & HIST_FIELD_FL_ALIAS) 5943 seq_printf(m, " var_ref_idx (into hist_data->var_refs[]): %u\n", 5944 field->var_ref_idx); 5945 5946 if (field->flags & HIST_FIELD_FL_VAR_REF) { 5947 seq_printf(m, " name: %s\n", field->name); 5948 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n", 5949 field->var.idx); 5950 seq_printf(m, " var.hist_data: %p\n", field->var.hist_data); 5951 seq_printf(m, " var_ref_idx (into hist_data->var_refs[]): %u\n", 5952 field->var_ref_idx); 5953 if (field->system) 5954 seq_printf(m, " system: %s\n", field->system); 5955 if (field->event_name) 5956 seq_printf(m, " event_name: %s\n", field->event_name); 5957 } 5958 5959 seq_printf(m, " type: %s\n", field->type); 5960 seq_printf(m, " size: %u\n", field->size); 5961 seq_printf(m, " is_signed: %u\n", field->is_signed); 5962 seq_printf(m, " function: hist_field_%s()\n", field_funcs[field->fn_num]); 5963 5964 return 0; 5965 } 5966 5967 static int field_var_debug_show(struct seq_file *m, 5968 struct field_var *field_var, unsigned int i, 5969 bool save_vars) 5970 { 5971 const char *vars_name = save_vars ? "save_vars" : "field_vars"; 5972 struct hist_field *field; 5973 int ret = 0; 5974 5975 seq_printf(m, "\n hist_data->%s[%d]:\n", vars_name, i); 5976 5977 field = field_var->var; 5978 5979 seq_printf(m, "\n %s[%d].var:\n", vars_name, i); 5980 5981 hist_field_debug_show_flags(m, field->flags); 5982 seq_printf(m, " var.name: %s\n", field->var.name); 5983 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n", 5984 field->var.idx); 5985 5986 field = field_var->val; 5987 5988 seq_printf(m, "\n %s[%d].val:\n", vars_name, i); 5989 if (field->field) 5990 seq_printf(m, " ftrace_event_field name: %s\n", 5991 field->field->name); 5992 else { 5993 ret = -EINVAL; 5994 goto out; 5995 } 5996 5997 seq_printf(m, " type: %s\n", field->type); 5998 seq_printf(m, " size: %u\n", field->size); 5999 seq_printf(m, " is_signed: %u\n", field->is_signed); 6000 out: 6001 return ret; 6002 } 6003 6004 static int hist_action_debug_show(struct seq_file *m, 6005 struct action_data *data, int i) 6006 { 6007 int ret = 0; 6008 6009 if (data->handler == HANDLER_ONMAX || 6010 data->handler == HANDLER_ONCHANGE) { 6011 seq_printf(m, "\n hist_data->actions[%d].track_data.var_ref:\n", i); 6012 ret = hist_field_debug_show(m, data->track_data.var_ref, 6013 HIST_FIELD_FL_VAR_REF); 6014 if (ret) 6015 goto out; 6016 6017 seq_printf(m, "\n hist_data->actions[%d].track_data.track_var:\n", i); 6018 ret = hist_field_debug_show(m, data->track_data.track_var, 6019 HIST_FIELD_FL_VAR); 6020 if (ret) 6021 goto out; 6022 } 6023 6024 if (data->handler == HANDLER_ONMATCH) { 6025 seq_printf(m, "\n hist_data->actions[%d].match_data.event_system: %s\n", 6026 i, data->match_data.event_system); 6027 seq_printf(m, " hist_data->actions[%d].match_data.event: %s\n", 6028 i, data->match_data.event); 6029 } 6030 out: 6031 return ret; 6032 } 6033 6034 static int hist_actions_debug_show(struct seq_file *m, 6035 struct hist_trigger_data *hist_data) 6036 { 6037 int i, ret = 0; 6038 6039 if (hist_data->n_actions) 6040 seq_puts(m, "\n action tracking variables (for onmax()/onchange()/onmatch()):\n"); 6041 6042 for (i = 0; i < hist_data->n_actions; i++) { 6043 struct action_data *action = hist_data->actions[i]; 6044 6045 ret = hist_action_debug_show(m, action, i); 6046 if (ret) 6047 goto out; 6048 } 6049 6050 if (hist_data->n_save_vars) 6051 seq_puts(m, "\n save action variables (save() params):\n"); 6052 6053 for (i = 0; i < hist_data->n_save_vars; i++) { 6054 ret = field_var_debug_show(m, hist_data->save_vars[i], i, true); 6055 if (ret) 6056 goto out; 6057 } 6058 out: 6059 return ret; 6060 } 6061 6062 static void hist_trigger_debug_show(struct seq_file *m, 6063 struct event_trigger_data *data, int n) 6064 { 6065 struct hist_trigger_data *hist_data; 6066 int i, ret; 6067 6068 if (n > 0) 6069 seq_puts(m, "\n\n"); 6070 6071 seq_puts(m, "# event histogram\n#\n# trigger info: "); 6072 data->cmd_ops->print(m, data); 6073 seq_puts(m, "#\n\n"); 6074 6075 hist_data = data->private_data; 6076 6077 seq_printf(m, "hist_data: %p\n\n", hist_data); 6078 seq_printf(m, " n_vals: %u\n", hist_data->n_vals); 6079 seq_printf(m, " n_keys: %u\n", hist_data->n_keys); 6080 seq_printf(m, " n_fields: %u\n", hist_data->n_fields); 6081 6082 seq_puts(m, "\n val fields:\n\n"); 6083 6084 seq_puts(m, " hist_data->fields[0]:\n"); 6085 ret = hist_field_debug_show(m, hist_data->fields[0], 6086 HIST_FIELD_FL_HITCOUNT); 6087 if (ret) 6088 return; 6089 6090 for (i = 1; i < hist_data->n_vals; i++) { 6091 seq_printf(m, "\n hist_data->fields[%d]:\n", i); 6092 ret = hist_field_debug_show(m, hist_data->fields[i], 0); 6093 if (ret) 6094 return; 6095 } 6096 6097 seq_puts(m, "\n key fields:\n"); 6098 6099 for (i = hist_data->n_vals; i < hist_data->n_fields; i++) { 6100 seq_printf(m, "\n hist_data->fields[%d]:\n", i); 6101 ret = hist_field_debug_show(m, hist_data->fields[i], 6102 HIST_FIELD_FL_KEY); 6103 if (ret) 6104 return; 6105 } 6106 6107 if (hist_data->n_var_refs) 6108 seq_puts(m, "\n variable reference fields:\n"); 6109 6110 for (i = 0; i < hist_data->n_var_refs; i++) { 6111 seq_printf(m, "\n hist_data->var_refs[%d]:\n", i); 6112 ret = hist_field_debug_show(m, hist_data->var_refs[i], 6113 HIST_FIELD_FL_VAR_REF); 6114 if (ret) 6115 return; 6116 } 6117 6118 if (hist_data->n_field_vars) 6119 seq_puts(m, "\n field variables:\n"); 6120 6121 for (i = 0; i < hist_data->n_field_vars; i++) { 6122 ret = field_var_debug_show(m, hist_data->field_vars[i], i, false); 6123 if (ret) 6124 return; 6125 } 6126 6127 ret = hist_actions_debug_show(m, hist_data); 6128 if (ret) 6129 return; 6130 } 6131 6132 static int hist_debug_show(struct seq_file *m, void *v) 6133 { 6134 struct event_trigger_data *data; 6135 struct trace_event_file *event_file; 6136 int n = 0; 6137 6138 guard(mutex)(&event_mutex); 6139 6140 event_file = event_file_file(m->private); 6141 if (unlikely(!event_file)) 6142 return -ENODEV; 6143 6144 list_for_each_entry(data, &event_file->triggers, list) { 6145 if (data->cmd_ops->trigger_type == ETT_EVENT_HIST) 6146 hist_trigger_debug_show(m, data, n++); 6147 } 6148 return 0; 6149 } 6150 6151 static int event_hist_debug_open(struct inode *inode, struct file *file) 6152 { 6153 int ret; 6154 6155 ret = tracing_open_file_tr(inode, file); 6156 if (ret) 6157 return ret; 6158 6159 ret = single_open(file, hist_debug_show, file); 6160 if (ret) 6161 tracing_release_file_tr(inode, file); 6162 return ret; 6163 } 6164 6165 const struct file_operations event_hist_debug_fops = { 6166 .open = event_hist_debug_open, 6167 .read = seq_read, 6168 .llseek = seq_lseek, 6169 .release = tracing_single_release_file_tr, 6170 }; 6171 #endif 6172 6173 static void hist_field_print(struct seq_file *m, struct hist_field *hist_field) 6174 { 6175 const char *field_name = hist_field_name(hist_field, 0); 6176 6177 if (hist_field->var.name) 6178 seq_printf(m, "%s=", hist_field->var.name); 6179 6180 if (hist_field->flags & HIST_FIELD_FL_CPU) 6181 seq_puts(m, "common_cpu"); 6182 if (hist_field->flags & HIST_FIELD_FL_COMM) 6183 seq_puts(m, "common_comm"); 6184 else if (hist_field->flags & HIST_FIELD_FL_CONST) 6185 seq_printf(m, "%llu", hist_field->constant); 6186 else if (field_name) { 6187 if (hist_field->flags & HIST_FIELD_FL_VAR_REF || 6188 hist_field->flags & HIST_FIELD_FL_ALIAS) 6189 if (!hist_field->system) 6190 seq_putc(m, '$'); 6191 seq_printf(m, "%s", field_name); 6192 } else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP) 6193 seq_puts(m, "common_timestamp"); 6194 6195 if (hist_field->flags) { 6196 if (!(hist_field->flags & HIST_FIELD_FL_VAR_REF) && 6197 !(hist_field->flags & HIST_FIELD_FL_EXPR) && 6198 !(hist_field->flags & HIST_FIELD_FL_STACKTRACE)) { 6199 const char *flags = get_hist_field_flags(hist_field); 6200 6201 if (flags) 6202 seq_printf(m, ".%s", flags); 6203 } 6204 } 6205 if (hist_field->buckets) 6206 seq_printf(m, "=%ld", hist_field->buckets); 6207 } 6208 6209 static int event_hist_trigger_print(struct seq_file *m, 6210 struct event_trigger_data *data) 6211 { 6212 struct hist_trigger_data *hist_data = data->private_data; 6213 struct hist_field *field; 6214 bool have_var = false; 6215 bool show_val = false; 6216 unsigned int i; 6217 6218 seq_puts(m, HIST_PREFIX); 6219 6220 if (data->name) 6221 seq_printf(m, "%s:", data->name); 6222 6223 seq_puts(m, "keys="); 6224 6225 for_each_hist_key_field(i, hist_data) { 6226 field = hist_data->fields[i]; 6227 6228 if (i > hist_data->n_vals) 6229 seq_puts(m, ","); 6230 6231 if (field->flags & HIST_FIELD_FL_STACKTRACE) { 6232 if (field->field) 6233 seq_printf(m, "%s.stacktrace", field->field->name); 6234 else 6235 seq_puts(m, "common_stacktrace"); 6236 } else 6237 hist_field_print(m, field); 6238 } 6239 6240 seq_puts(m, ":vals="); 6241 6242 for_each_hist_val_field(i, hist_data) { 6243 field = hist_data->fields[i]; 6244 if (field->flags & HIST_FIELD_FL_VAR) { 6245 have_var = true; 6246 continue; 6247 } 6248 6249 if (i == HITCOUNT_IDX) { 6250 if (hist_data->attrs->no_hitcount) 6251 continue; 6252 seq_puts(m, "hitcount"); 6253 } else { 6254 if (show_val) 6255 seq_puts(m, ","); 6256 hist_field_print(m, field); 6257 } 6258 show_val = true; 6259 } 6260 6261 if (have_var) { 6262 unsigned int n = 0; 6263 6264 seq_puts(m, ":"); 6265 6266 for_each_hist_val_field(i, hist_data) { 6267 field = hist_data->fields[i]; 6268 6269 if (field->flags & HIST_FIELD_FL_VAR) { 6270 if (n++) 6271 seq_puts(m, ","); 6272 hist_field_print(m, field); 6273 } 6274 } 6275 } 6276 6277 seq_puts(m, ":sort="); 6278 6279 for (i = 0; i < hist_data->n_sort_keys; i++) { 6280 struct tracing_map_sort_key *sort_key; 6281 unsigned int idx, first_key_idx; 6282 6283 /* skip VAR vals */ 6284 first_key_idx = hist_data->n_vals - hist_data->n_vars; 6285 6286 sort_key = &hist_data->sort_keys[i]; 6287 idx = sort_key->field_idx; 6288 6289 if (WARN_ON(idx >= HIST_FIELDS_MAX)) 6290 return -EINVAL; 6291 6292 if (i > 0) 6293 seq_puts(m, ","); 6294 6295 if (idx == HITCOUNT_IDX) 6296 seq_puts(m, "hitcount"); 6297 else { 6298 if (idx >= first_key_idx) 6299 idx += hist_data->n_vars; 6300 hist_field_print(m, hist_data->fields[idx]); 6301 } 6302 6303 if (sort_key->descending) 6304 seq_puts(m, ".descending"); 6305 } 6306 seq_printf(m, ":size=%u", (1 << hist_data->map->map_bits)); 6307 if (hist_data->enable_timestamps) 6308 seq_printf(m, ":clock=%s", hist_data->attrs->clock); 6309 if (hist_data->attrs->no_hitcount) 6310 seq_puts(m, ":nohitcount"); 6311 6312 print_actions_spec(m, hist_data); 6313 6314 if (data->filter_str) 6315 seq_printf(m, " if %s", data->filter_str); 6316 6317 if (data->paused) 6318 seq_puts(m, " [paused]"); 6319 else 6320 seq_puts(m, " [active]"); 6321 6322 seq_putc(m, '\n'); 6323 6324 return 0; 6325 } 6326 6327 static int event_hist_trigger_init(struct event_trigger_data *data) 6328 { 6329 struct hist_trigger_data *hist_data = data->private_data; 6330 6331 if (alloc_hist_pad() < 0) 6332 return -ENOMEM; 6333 6334 if (!data->ref && hist_data->attrs->name) 6335 save_named_trigger(hist_data->attrs->name, data); 6336 6337 data->ref++; 6338 6339 return 0; 6340 } 6341 6342 static void unregister_field_var_hists(struct hist_trigger_data *hist_data) 6343 { 6344 struct trace_event_file *file; 6345 unsigned int i; 6346 char *cmd; 6347 int ret; 6348 6349 for (i = 0; i < hist_data->n_field_var_hists; i++) { 6350 file = hist_data->field_var_hists[i]->hist_data->event_file; 6351 cmd = hist_data->field_var_hists[i]->cmd; 6352 ret = event_hist_trigger_parse(&trigger_hist_cmd, file, 6353 "!hist", "hist", cmd); 6354 WARN_ON_ONCE(ret < 0); 6355 } 6356 } 6357 6358 static void event_hist_trigger_free(struct event_trigger_data *data) 6359 { 6360 struct hist_trigger_data *hist_data = data->private_data; 6361 6362 if (WARN_ON_ONCE(data->ref <= 0)) 6363 return; 6364 6365 data->ref--; 6366 if (!data->ref) { 6367 if (data->name) 6368 del_named_trigger(data); 6369 6370 trigger_data_free(data); 6371 6372 tracepoint_synchronize_unregister(); 6373 remove_hist_vars(hist_data); 6374 6375 unregister_field_var_hists(hist_data); 6376 6377 destroy_hist_data(hist_data); 6378 } 6379 free_hist_pad(); 6380 } 6381 6382 static int event_hist_trigger_named_init(struct event_trigger_data *data) 6383 { 6384 int ret; 6385 6386 data->ref++; 6387 6388 save_named_trigger(data->named_data->name, data); 6389 6390 ret = event_hist_trigger_init(data->named_data); 6391 if (ret < 0) { 6392 kfree(data->cmd_ops); 6393 data->cmd_ops = &trigger_hist_cmd; 6394 } 6395 6396 return ret; 6397 } 6398 6399 static void event_hist_trigger_named_free(struct event_trigger_data *data) 6400 { 6401 if (WARN_ON_ONCE(data->ref <= 0)) 6402 return; 6403 6404 event_hist_trigger_free(data->named_data); 6405 6406 data->ref--; 6407 if (!data->ref) { 6408 struct event_command *cmd_ops = data->cmd_ops; 6409 6410 del_named_trigger(data); 6411 trigger_data_free(data); 6412 tracepoint_synchronize_unregister(); 6413 kfree(cmd_ops); 6414 } 6415 } 6416 6417 static void hist_clear(struct event_trigger_data *data) 6418 { 6419 struct hist_trigger_data *hist_data = data->private_data; 6420 6421 if (data->name) 6422 pause_named_trigger(data); 6423 6424 tracepoint_synchronize_unregister(); 6425 6426 tracing_map_clear(hist_data->map); 6427 6428 if (data->name) 6429 unpause_named_trigger(data); 6430 } 6431 6432 static bool compatible_field(struct ftrace_event_field *field, 6433 struct ftrace_event_field *test_field) 6434 { 6435 if (field == test_field) 6436 return true; 6437 if (field == NULL || test_field == NULL) 6438 return false; 6439 if (strcmp(field->name, test_field->name) != 0) 6440 return false; 6441 if (strcmp(field->type, test_field->type) != 0) 6442 return false; 6443 if (field->size != test_field->size) 6444 return false; 6445 if (field->is_signed != test_field->is_signed) 6446 return false; 6447 6448 return true; 6449 } 6450 6451 static bool hist_trigger_match(struct event_trigger_data *data, 6452 struct event_trigger_data *data_test, 6453 struct event_trigger_data *named_data, 6454 bool ignore_filter) 6455 { 6456 struct tracing_map_sort_key *sort_key, *sort_key_test; 6457 struct hist_trigger_data *hist_data, *hist_data_test; 6458 struct hist_field *key_field, *key_field_test; 6459 unsigned int i; 6460 6461 if (named_data && (named_data != data_test) && 6462 (named_data != data_test->named_data)) 6463 return false; 6464 6465 if (!named_data && is_named_trigger(data_test)) 6466 return false; 6467 6468 hist_data = data->private_data; 6469 hist_data_test = data_test->private_data; 6470 6471 if (hist_data->n_vals != hist_data_test->n_vals || 6472 hist_data->n_fields != hist_data_test->n_fields || 6473 hist_data->n_sort_keys != hist_data_test->n_sort_keys) 6474 return false; 6475 6476 if (!ignore_filter) { 6477 if ((data->filter_str && !data_test->filter_str) || 6478 (!data->filter_str && data_test->filter_str)) 6479 return false; 6480 } 6481 6482 for_each_hist_field(i, hist_data) { 6483 key_field = hist_data->fields[i]; 6484 key_field_test = hist_data_test->fields[i]; 6485 6486 if (key_field->flags != key_field_test->flags) 6487 return false; 6488 if (!compatible_field(key_field->field, key_field_test->field)) 6489 return false; 6490 if (key_field->offset != key_field_test->offset) 6491 return false; 6492 if (key_field->size != key_field_test->size) 6493 return false; 6494 if (key_field->is_signed != key_field_test->is_signed) 6495 return false; 6496 if (!!key_field->var.name != !!key_field_test->var.name) 6497 return false; 6498 if (key_field->var.name && 6499 strcmp(key_field->var.name, key_field_test->var.name) != 0) 6500 return false; 6501 } 6502 6503 for (i = 0; i < hist_data->n_sort_keys; i++) { 6504 sort_key = &hist_data->sort_keys[i]; 6505 sort_key_test = &hist_data_test->sort_keys[i]; 6506 6507 if (sort_key->field_idx != sort_key_test->field_idx || 6508 sort_key->descending != sort_key_test->descending) 6509 return false; 6510 } 6511 6512 if (!ignore_filter && data->filter_str && 6513 (strcmp(data->filter_str, data_test->filter_str) != 0)) 6514 return false; 6515 6516 if (!actions_match(hist_data, hist_data_test)) 6517 return false; 6518 6519 return true; 6520 } 6521 6522 static bool existing_hist_update_only(char *glob, 6523 struct event_trigger_data *data, 6524 struct trace_event_file *file) 6525 { 6526 struct hist_trigger_data *hist_data = data->private_data; 6527 struct event_trigger_data *test, *named_data = NULL; 6528 bool updated = false; 6529 6530 if (!hist_data->attrs->pause && !hist_data->attrs->cont && 6531 !hist_data->attrs->clear) 6532 goto out; 6533 6534 if (hist_data->attrs->name) { 6535 named_data = find_named_trigger(hist_data->attrs->name); 6536 if (named_data) { 6537 if (!hist_trigger_match(data, named_data, named_data, 6538 true)) 6539 goto out; 6540 } 6541 } 6542 6543 if (hist_data->attrs->name && !named_data) 6544 goto out; 6545 6546 list_for_each_entry(test, &file->triggers, list) { 6547 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6548 if (!hist_trigger_match(data, test, named_data, false)) 6549 continue; 6550 if (hist_data->attrs->pause) 6551 test->paused = true; 6552 else if (hist_data->attrs->cont) 6553 test->paused = false; 6554 else if (hist_data->attrs->clear) 6555 hist_clear(test); 6556 updated = true; 6557 goto out; 6558 } 6559 } 6560 out: 6561 return updated; 6562 } 6563 6564 /* 6565 * Set or disable using the per CPU trace_buffer_event when possible. 6566 */ 6567 static int tracing_set_filter_buffering(struct trace_array *tr, bool set) 6568 { 6569 guard(mutex)(&trace_types_lock); 6570 6571 if (set && tr->no_filter_buffering_ref++) 6572 return 0; 6573 6574 if (!set) { 6575 if (WARN_ON_ONCE(!tr->no_filter_buffering_ref)) 6576 return -EINVAL; 6577 6578 --tr->no_filter_buffering_ref; 6579 } 6580 6581 return 0; 6582 } 6583 6584 static int hist_register_trigger(char *glob, 6585 struct event_trigger_data *data, 6586 struct trace_event_file *file) 6587 { 6588 struct hist_trigger_data *hist_data = data->private_data; 6589 struct event_trigger_data *test, *named_data = NULL; 6590 struct trace_array *tr = file->tr; 6591 int ret = 0; 6592 6593 if (hist_data->attrs->name) { 6594 named_data = find_named_trigger(hist_data->attrs->name); 6595 if (named_data) { 6596 if (!hist_trigger_match(data, named_data, named_data, 6597 true)) { 6598 hist_err(tr, HIST_ERR_NAMED_MISMATCH, errpos(hist_data->attrs->name)); 6599 ret = -EINVAL; 6600 goto out; 6601 } 6602 } 6603 } 6604 6605 if (hist_data->attrs->name && !named_data) 6606 goto new; 6607 6608 lockdep_assert_held(&event_mutex); 6609 6610 list_for_each_entry(test, &file->triggers, list) { 6611 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6612 if (hist_trigger_match(data, test, named_data, false)) { 6613 hist_err(tr, HIST_ERR_TRIGGER_EEXIST, 0); 6614 ret = -EEXIST; 6615 goto out; 6616 } 6617 } 6618 } 6619 new: 6620 if (hist_data->attrs->cont || hist_data->attrs->clear) { 6621 hist_err(tr, HIST_ERR_TRIGGER_ENOENT_CLEAR, 0); 6622 ret = -ENOENT; 6623 goto out; 6624 } 6625 6626 if (hist_data->attrs->pause) 6627 data->paused = true; 6628 6629 if (named_data) { 6630 struct event_command *cmd_ops; 6631 6632 data->private_data = named_data->private_data; 6633 set_named_trigger_data(data, named_data); 6634 /* Copy the command ops and update some of the functions */ 6635 cmd_ops = kmalloc_obj(*cmd_ops); 6636 if (!cmd_ops) { 6637 ret = -ENOMEM; 6638 goto out; 6639 } 6640 *cmd_ops = *data->cmd_ops; 6641 cmd_ops->init = event_hist_trigger_named_init; 6642 cmd_ops->free = event_hist_trigger_named_free; 6643 data->cmd_ops = cmd_ops; 6644 } 6645 6646 if (data->cmd_ops->init) { 6647 ret = data->cmd_ops->init(data); 6648 if (ret < 0) 6649 goto out; 6650 } 6651 6652 if (hist_data->enable_timestamps) { 6653 char *clock = hist_data->attrs->clock; 6654 6655 ret = tracing_set_clock(file->tr, hist_data->attrs->clock); 6656 if (ret) { 6657 hist_err(tr, HIST_ERR_SET_CLOCK_FAIL, errpos(clock)); 6658 goto out; 6659 } 6660 6661 tracing_set_filter_buffering(file->tr, true); 6662 } 6663 6664 if (named_data) 6665 destroy_hist_data(hist_data); 6666 out: 6667 return ret; 6668 } 6669 6670 static int hist_trigger_enable(struct event_trigger_data *data, 6671 struct trace_event_file *file) 6672 { 6673 int ret = 0; 6674 6675 list_add_tail_rcu(&data->list, &file->triggers); 6676 6677 update_cond_flag(file); 6678 6679 if (trace_event_trigger_enable_disable(file, 1) < 0) { 6680 list_del_rcu(&data->list); 6681 update_cond_flag(file); 6682 ret--; 6683 } 6684 6685 return ret; 6686 } 6687 6688 static bool have_hist_trigger_match(struct event_trigger_data *data, 6689 struct trace_event_file *file) 6690 { 6691 struct hist_trigger_data *hist_data = data->private_data; 6692 struct event_trigger_data *test, *named_data = NULL; 6693 bool match = false; 6694 6695 lockdep_assert_held(&event_mutex); 6696 6697 if (hist_data->attrs->name) 6698 named_data = find_named_trigger(hist_data->attrs->name); 6699 6700 list_for_each_entry(test, &file->triggers, list) { 6701 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6702 if (hist_trigger_match(data, test, named_data, false)) { 6703 match = true; 6704 break; 6705 } 6706 } 6707 } 6708 6709 return match; 6710 } 6711 6712 static bool hist_trigger_check_refs(struct event_trigger_data *data, 6713 struct trace_event_file *file) 6714 { 6715 struct hist_trigger_data *hist_data = data->private_data; 6716 struct event_trigger_data *test, *named_data = NULL; 6717 6718 lockdep_assert_held(&event_mutex); 6719 6720 if (hist_data->attrs->name) 6721 named_data = find_named_trigger(hist_data->attrs->name); 6722 6723 list_for_each_entry(test, &file->triggers, list) { 6724 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6725 if (!hist_trigger_match(data, test, named_data, false)) 6726 continue; 6727 hist_data = test->private_data; 6728 if (check_var_refs(hist_data)) 6729 return true; 6730 break; 6731 } 6732 } 6733 6734 return false; 6735 } 6736 6737 static void hist_unregister_trigger(char *glob, 6738 struct event_trigger_data *data, 6739 struct trace_event_file *file) 6740 { 6741 struct event_trigger_data *test = NULL, *iter, *named_data = NULL; 6742 struct hist_trigger_data *hist_data = data->private_data; 6743 6744 lockdep_assert_held(&event_mutex); 6745 6746 if (hist_data->attrs->name) 6747 named_data = find_named_trigger(hist_data->attrs->name); 6748 6749 list_for_each_entry(iter, &file->triggers, list) { 6750 if (iter->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6751 if (!hist_trigger_match(data, iter, named_data, false)) 6752 continue; 6753 test = iter; 6754 list_del_rcu(&test->list); 6755 trace_event_trigger_enable_disable(file, 0); 6756 update_cond_flag(file); 6757 break; 6758 } 6759 } 6760 6761 if (test && test->cmd_ops->free) 6762 test->cmd_ops->free(test); 6763 6764 if (hist_data->enable_timestamps) { 6765 if (!hist_data->remove || test) 6766 tracing_set_filter_buffering(file->tr, false); 6767 } 6768 } 6769 6770 static bool hist_file_check_refs(struct trace_event_file *file) 6771 { 6772 struct hist_trigger_data *hist_data; 6773 struct event_trigger_data *test; 6774 6775 lockdep_assert_held(&event_mutex); 6776 6777 list_for_each_entry(test, &file->triggers, list) { 6778 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6779 hist_data = test->private_data; 6780 if (check_var_refs(hist_data)) 6781 return true; 6782 } 6783 } 6784 6785 return false; 6786 } 6787 6788 static void hist_unreg_all(struct trace_event_file *file) 6789 { 6790 struct event_trigger_data *test, *n; 6791 struct hist_trigger_data *hist_data; 6792 struct synth_event *se; 6793 const char *se_name; 6794 6795 lockdep_assert_held(&event_mutex); 6796 6797 if (hist_file_check_refs(file)) 6798 return; 6799 6800 list_for_each_entry_safe(test, n, &file->triggers, list) { 6801 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6802 hist_data = test->private_data; 6803 list_del_rcu(&test->list); 6804 trace_event_trigger_enable_disable(file, 0); 6805 6806 se_name = trace_event_name(file->event_call); 6807 se = find_synth_event(se_name); 6808 if (se) 6809 se->ref--; 6810 6811 update_cond_flag(file); 6812 if (hist_data->enable_timestamps) 6813 tracing_set_filter_buffering(file->tr, false); 6814 if (test->cmd_ops->free) 6815 test->cmd_ops->free(test); 6816 } 6817 } 6818 } 6819 6820 static int event_hist_trigger_parse(struct event_command *cmd_ops, 6821 struct trace_event_file *file, 6822 char *glob, char *cmd, 6823 char *param_and_filter) 6824 { 6825 unsigned int hist_trigger_bits = TRACING_MAP_BITS_DEFAULT; 6826 struct event_trigger_data *trigger_data; 6827 struct hist_trigger_attrs *attrs; 6828 struct hist_trigger_data *hist_data; 6829 char *param, *filter, *p, *start; 6830 struct synth_event *se; 6831 const char *se_name; 6832 bool remove; 6833 int ret = 0; 6834 6835 lockdep_assert_held(&event_mutex); 6836 6837 if (WARN_ON(!glob)) 6838 return -EINVAL; 6839 6840 if (glob[0]) { 6841 hist_err_clear(); 6842 last_cmd_set(file, param_and_filter); 6843 } 6844 6845 remove = event_trigger_check_remove(glob); 6846 6847 if (event_trigger_empty_param(param_and_filter)) 6848 return -EINVAL; 6849 6850 /* 6851 * separate the trigger from the filter (k:v [if filter]) 6852 * allowing for whitespace in the trigger 6853 */ 6854 p = param = param_and_filter; 6855 do { 6856 p = strstr(p, "if"); 6857 if (!p) 6858 break; 6859 if (p == param_and_filter) 6860 return -EINVAL; 6861 if (*(p - 1) != ' ' && *(p - 1) != '\t') { 6862 p++; 6863 continue; 6864 } 6865 if (p >= param_and_filter + strlen(param_and_filter) - (sizeof("if") - 1) - 1) 6866 return -EINVAL; 6867 if (*(p + sizeof("if") - 1) != ' ' && *(p + sizeof("if") - 1) != '\t') { 6868 p++; 6869 continue; 6870 } 6871 break; 6872 } while (1); 6873 6874 if (!p) 6875 filter = NULL; 6876 else { 6877 *(p - 1) = '\0'; 6878 filter = strstrip(p); 6879 param = strstrip(param); 6880 } 6881 6882 /* 6883 * To simplify arithmetic expression parsing, replace occurrences of 6884 * '.sym-offset' modifier with '.symXoffset' 6885 */ 6886 start = strstr(param, ".sym-offset"); 6887 while (start) { 6888 *(start + 4) = 'X'; 6889 start = strstr(start + 11, ".sym-offset"); 6890 } 6891 6892 attrs = parse_hist_trigger_attrs(file->tr, param); 6893 if (IS_ERR(attrs)) 6894 return PTR_ERR(attrs); 6895 6896 if (attrs->map_bits) 6897 hist_trigger_bits = attrs->map_bits; 6898 6899 hist_data = create_hist_data(hist_trigger_bits, attrs, file, remove); 6900 if (IS_ERR(hist_data)) { 6901 destroy_hist_trigger_attrs(attrs); 6902 return PTR_ERR(hist_data); 6903 } 6904 6905 trigger_data = trigger_data_alloc(cmd_ops, cmd, param, hist_data); 6906 if (!trigger_data) { 6907 ret = -ENOMEM; 6908 goto out_free; 6909 } 6910 6911 ret = event_trigger_set_filter(cmd_ops, file, filter, trigger_data); 6912 if (ret < 0) 6913 goto out_free; 6914 6915 if (remove) { 6916 if (!have_hist_trigger_match(trigger_data, file)) 6917 goto out_free; 6918 6919 if (hist_trigger_check_refs(trigger_data, file)) { 6920 ret = -EBUSY; 6921 goto out_free; 6922 } 6923 6924 event_trigger_unregister(cmd_ops, file, glob+1, trigger_data); 6925 se_name = trace_event_name(file->event_call); 6926 se = find_synth_event(se_name); 6927 if (se) 6928 se->ref--; 6929 ret = 0; 6930 goto out_free; 6931 } 6932 6933 if (existing_hist_update_only(glob, trigger_data, file)) 6934 goto out_free; 6935 6936 if (!get_named_trigger_data(trigger_data)) { 6937 6938 ret = create_actions(hist_data); 6939 if (ret) 6940 goto out_free; 6941 6942 if (has_hist_vars(hist_data) || hist_data->n_var_refs) { 6943 ret = save_hist_vars(hist_data); 6944 if (ret) 6945 goto out_free; 6946 } 6947 6948 ret = tracing_map_init(hist_data->map); 6949 if (ret) 6950 goto out_free; 6951 } 6952 6953 ret = event_trigger_register(cmd_ops, file, glob, trigger_data); 6954 if (ret < 0) 6955 goto out_free; 6956 6957 ret = hist_trigger_enable(trigger_data, file); 6958 if (ret) 6959 goto out_unreg; 6960 6961 se_name = trace_event_name(file->event_call); 6962 se = find_synth_event(se_name); 6963 if (se) 6964 se->ref++; 6965 out: 6966 if (ret == 0 && glob[0]) 6967 hist_err_clear(); 6968 6969 return ret; 6970 out_unreg: 6971 event_trigger_unregister(cmd_ops, file, glob+1, trigger_data); 6972 out_free: 6973 remove_hist_vars(hist_data); 6974 6975 trigger_data_free(trigger_data); 6976 6977 destroy_hist_data(hist_data); 6978 goto out; 6979 } 6980 6981 static struct event_command trigger_hist_cmd = { 6982 .name = "hist", 6983 .trigger_type = ETT_EVENT_HIST, 6984 .flags = EVENT_CMD_FL_NEEDS_REC, 6985 .parse = event_hist_trigger_parse, 6986 .reg = hist_register_trigger, 6987 .unreg = hist_unregister_trigger, 6988 .unreg_all = hist_unreg_all, 6989 .set_filter = set_trigger_filter, 6990 .trigger = event_hist_trigger, 6991 .print = event_hist_trigger_print, 6992 .init = event_hist_trigger_init, 6993 .free = event_hist_trigger_free, 6994 }; 6995 6996 __init int register_trigger_hist_cmd(void) 6997 { 6998 int ret; 6999 7000 ret = register_event_command(&trigger_hist_cmd); 7001 WARN_ON(ret < 0); 7002 7003 return ret; 7004 } 7005 7006 static void 7007 hist_enable_trigger(struct event_trigger_data *data, 7008 struct trace_buffer *buffer, void *rec, 7009 struct ring_buffer_event *event) 7010 { 7011 struct enable_trigger_data *enable_data = data->private_data; 7012 struct event_trigger_data *test; 7013 7014 list_for_each_entry_rcu(test, &enable_data->file->triggers, list, 7015 lockdep_is_held(&event_mutex)) { 7016 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 7017 if (enable_data->enable) 7018 test->paused = false; 7019 else 7020 test->paused = true; 7021 } 7022 } 7023 } 7024 7025 static void hist_enable_unreg_all(struct trace_event_file *file) 7026 { 7027 struct event_trigger_data *test, *n; 7028 7029 list_for_each_entry_safe(test, n, &file->triggers, list) { 7030 if (test->cmd_ops->trigger_type == ETT_HIST_ENABLE) { 7031 list_del_rcu(&test->list); 7032 update_cond_flag(file); 7033 trace_event_trigger_enable_disable(file, 0); 7034 if (test->cmd_ops->free) 7035 test->cmd_ops->free(test); 7036 } 7037 } 7038 } 7039 7040 static struct event_command trigger_hist_enable_cmd = { 7041 .name = ENABLE_HIST_STR, 7042 .trigger_type = ETT_HIST_ENABLE, 7043 .parse = event_enable_trigger_parse, 7044 .reg = event_enable_register_trigger, 7045 .unreg = event_enable_unregister_trigger, 7046 .unreg_all = hist_enable_unreg_all, 7047 .set_filter = set_trigger_filter, 7048 .trigger = hist_enable_trigger, 7049 .count_func = event_trigger_count, 7050 .print = event_enable_trigger_print, 7051 .init = event_trigger_init, 7052 .free = event_enable_trigger_free, 7053 }; 7054 7055 static struct event_command trigger_hist_disable_cmd = { 7056 .name = DISABLE_HIST_STR, 7057 .trigger_type = ETT_HIST_ENABLE, 7058 .parse = event_enable_trigger_parse, 7059 .reg = event_enable_register_trigger, 7060 .unreg = event_enable_unregister_trigger, 7061 .unreg_all = hist_enable_unreg_all, 7062 .set_filter = set_trigger_filter, 7063 .trigger = hist_enable_trigger, 7064 .count_func = event_trigger_count, 7065 .print = event_enable_trigger_print, 7066 .init = event_trigger_init, 7067 .free = event_enable_trigger_free, 7068 }; 7069 7070 static __init void unregister_trigger_hist_enable_disable_cmds(void) 7071 { 7072 unregister_event_command(&trigger_hist_enable_cmd); 7073 unregister_event_command(&trigger_hist_disable_cmd); 7074 } 7075 7076 __init int register_trigger_hist_enable_disable_cmds(void) 7077 { 7078 int ret; 7079 7080 ret = register_event_command(&trigger_hist_enable_cmd); 7081 if (WARN_ON(ret < 0)) 7082 return ret; 7083 ret = register_event_command(&trigger_hist_disable_cmd); 7084 if (WARN_ON(ret < 0)) 7085 unregister_trigger_hist_enable_disable_cmds(); 7086 7087 return ret; 7088 } 7089