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/mutex.h> 11 #include <linux/slab.h> 12 #include <linux/stacktrace.h> 13 #include <linux/rculist.h> 14 #include <linux/tracefs.h> 15 16 #include "tracing_map.h" 17 #include "trace.h" 18 #include "trace_dynevent.h" 19 20 #define SYNTH_SYSTEM "synthetic" 21 #define SYNTH_FIELDS_MAX 16 22 23 #define STR_VAR_LEN_MAX 32 /* must be multiple of sizeof(u64) */ 24 25 struct hist_field; 26 27 typedef u64 (*hist_field_fn_t) (struct hist_field *field, 28 struct tracing_map_elt *elt, 29 struct ring_buffer_event *rbe, 30 void *event); 31 32 #define HIST_FIELD_OPERANDS_MAX 2 33 #define HIST_FIELDS_MAX (TRACING_MAP_FIELDS_MAX + TRACING_MAP_VARS_MAX) 34 #define HIST_ACTIONS_MAX 8 35 36 enum field_op_id { 37 FIELD_OP_NONE, 38 FIELD_OP_PLUS, 39 FIELD_OP_MINUS, 40 FIELD_OP_UNARY_MINUS, 41 }; 42 43 /* 44 * A hist_var (histogram variable) contains variable information for 45 * hist_fields having the HIST_FIELD_FL_VAR or HIST_FIELD_FL_VAR_REF 46 * flag set. A hist_var has a variable name e.g. ts0, and is 47 * associated with a given histogram trigger, as specified by 48 * hist_data. The hist_var idx is the unique index assigned to the 49 * variable by the hist trigger's tracing_map. The idx is what is 50 * used to set a variable's value and, by a variable reference, to 51 * retrieve it. 52 */ 53 struct hist_var { 54 char *name; 55 struct hist_trigger_data *hist_data; 56 unsigned int idx; 57 }; 58 59 struct hist_field { 60 struct ftrace_event_field *field; 61 unsigned long flags; 62 hist_field_fn_t fn; 63 unsigned int size; 64 unsigned int offset; 65 unsigned int is_signed; 66 const char *type; 67 struct hist_field *operands[HIST_FIELD_OPERANDS_MAX]; 68 struct hist_trigger_data *hist_data; 69 70 /* 71 * Variable fields contain variable-specific info in var. 72 */ 73 struct hist_var var; 74 enum field_op_id operator; 75 char *system; 76 char *event_name; 77 78 /* 79 * The name field is used for EXPR and VAR_REF fields. VAR 80 * fields contain the variable name in var.name. 81 */ 82 char *name; 83 84 /* 85 * When a histogram trigger is hit, if it has any references 86 * to variables, the values of those variables are collected 87 * into a var_ref_vals array by resolve_var_refs(). The 88 * current value of each variable is read from the tracing_map 89 * using the hist field's hist_var.idx and entered into the 90 * var_ref_idx entry i.e. var_ref_vals[var_ref_idx]. 91 */ 92 unsigned int var_ref_idx; 93 bool read_once; 94 }; 95 96 static u64 hist_field_none(struct hist_field *field, 97 struct tracing_map_elt *elt, 98 struct ring_buffer_event *rbe, 99 void *event) 100 { 101 return 0; 102 } 103 104 static u64 hist_field_counter(struct hist_field *field, 105 struct tracing_map_elt *elt, 106 struct ring_buffer_event *rbe, 107 void *event) 108 { 109 return 1; 110 } 111 112 static u64 hist_field_string(struct hist_field *hist_field, 113 struct tracing_map_elt *elt, 114 struct ring_buffer_event *rbe, 115 void *event) 116 { 117 char *addr = (char *)(event + hist_field->field->offset); 118 119 return (u64)(unsigned long)addr; 120 } 121 122 static u64 hist_field_dynstring(struct hist_field *hist_field, 123 struct tracing_map_elt *elt, 124 struct ring_buffer_event *rbe, 125 void *event) 126 { 127 u32 str_item = *(u32 *)(event + hist_field->field->offset); 128 int str_loc = str_item & 0xffff; 129 char *addr = (char *)(event + str_loc); 130 131 return (u64)(unsigned long)addr; 132 } 133 134 static u64 hist_field_pstring(struct hist_field *hist_field, 135 struct tracing_map_elt *elt, 136 struct ring_buffer_event *rbe, 137 void *event) 138 { 139 char **addr = (char **)(event + hist_field->field->offset); 140 141 return (u64)(unsigned long)*addr; 142 } 143 144 static u64 hist_field_log2(struct hist_field *hist_field, 145 struct tracing_map_elt *elt, 146 struct ring_buffer_event *rbe, 147 void *event) 148 { 149 struct hist_field *operand = hist_field->operands[0]; 150 151 u64 val = operand->fn(operand, elt, rbe, event); 152 153 return (u64) ilog2(roundup_pow_of_two(val)); 154 } 155 156 static u64 hist_field_plus(struct hist_field *hist_field, 157 struct tracing_map_elt *elt, 158 struct ring_buffer_event *rbe, 159 void *event) 160 { 161 struct hist_field *operand1 = hist_field->operands[0]; 162 struct hist_field *operand2 = hist_field->operands[1]; 163 164 u64 val1 = operand1->fn(operand1, elt, rbe, event); 165 u64 val2 = operand2->fn(operand2, elt, rbe, event); 166 167 return val1 + val2; 168 } 169 170 static u64 hist_field_minus(struct hist_field *hist_field, 171 struct tracing_map_elt *elt, 172 struct ring_buffer_event *rbe, 173 void *event) 174 { 175 struct hist_field *operand1 = hist_field->operands[0]; 176 struct hist_field *operand2 = hist_field->operands[1]; 177 178 u64 val1 = operand1->fn(operand1, elt, rbe, event); 179 u64 val2 = operand2->fn(operand2, elt, rbe, event); 180 181 return val1 - val2; 182 } 183 184 static u64 hist_field_unary_minus(struct hist_field *hist_field, 185 struct tracing_map_elt *elt, 186 struct ring_buffer_event *rbe, 187 void *event) 188 { 189 struct hist_field *operand = hist_field->operands[0]; 190 191 s64 sval = (s64)operand->fn(operand, elt, rbe, event); 192 u64 val = (u64)-sval; 193 194 return val; 195 } 196 197 #define DEFINE_HIST_FIELD_FN(type) \ 198 static u64 hist_field_##type(struct hist_field *hist_field, \ 199 struct tracing_map_elt *elt, \ 200 struct ring_buffer_event *rbe, \ 201 void *event) \ 202 { \ 203 type *addr = (type *)(event + hist_field->field->offset); \ 204 \ 205 return (u64)(unsigned long)*addr; \ 206 } 207 208 DEFINE_HIST_FIELD_FN(s64); 209 DEFINE_HIST_FIELD_FN(u64); 210 DEFINE_HIST_FIELD_FN(s32); 211 DEFINE_HIST_FIELD_FN(u32); 212 DEFINE_HIST_FIELD_FN(s16); 213 DEFINE_HIST_FIELD_FN(u16); 214 DEFINE_HIST_FIELD_FN(s8); 215 DEFINE_HIST_FIELD_FN(u8); 216 217 #define for_each_hist_field(i, hist_data) \ 218 for ((i) = 0; (i) < (hist_data)->n_fields; (i)++) 219 220 #define for_each_hist_val_field(i, hist_data) \ 221 for ((i) = 0; (i) < (hist_data)->n_vals; (i)++) 222 223 #define for_each_hist_key_field(i, hist_data) \ 224 for ((i) = (hist_data)->n_vals; (i) < (hist_data)->n_fields; (i)++) 225 226 #define HIST_STACKTRACE_DEPTH 16 227 #define HIST_STACKTRACE_SIZE (HIST_STACKTRACE_DEPTH * sizeof(unsigned long)) 228 #define HIST_STACKTRACE_SKIP 5 229 230 #define HITCOUNT_IDX 0 231 #define HIST_KEY_SIZE_MAX (MAX_FILTER_STR_VAL + HIST_STACKTRACE_SIZE) 232 233 enum hist_field_flags { 234 HIST_FIELD_FL_HITCOUNT = 1 << 0, 235 HIST_FIELD_FL_KEY = 1 << 1, 236 HIST_FIELD_FL_STRING = 1 << 2, 237 HIST_FIELD_FL_HEX = 1 << 3, 238 HIST_FIELD_FL_SYM = 1 << 4, 239 HIST_FIELD_FL_SYM_OFFSET = 1 << 5, 240 HIST_FIELD_FL_EXECNAME = 1 << 6, 241 HIST_FIELD_FL_SYSCALL = 1 << 7, 242 HIST_FIELD_FL_STACKTRACE = 1 << 8, 243 HIST_FIELD_FL_LOG2 = 1 << 9, 244 HIST_FIELD_FL_TIMESTAMP = 1 << 10, 245 HIST_FIELD_FL_TIMESTAMP_USECS = 1 << 11, 246 HIST_FIELD_FL_VAR = 1 << 12, 247 HIST_FIELD_FL_EXPR = 1 << 13, 248 HIST_FIELD_FL_VAR_REF = 1 << 14, 249 HIST_FIELD_FL_CPU = 1 << 15, 250 HIST_FIELD_FL_ALIAS = 1 << 16, 251 }; 252 253 struct var_defs { 254 unsigned int n_vars; 255 char *name[TRACING_MAP_VARS_MAX]; 256 char *expr[TRACING_MAP_VARS_MAX]; 257 }; 258 259 struct hist_trigger_attrs { 260 char *keys_str; 261 char *vals_str; 262 char *sort_key_str; 263 char *name; 264 char *clock; 265 bool pause; 266 bool cont; 267 bool clear; 268 bool ts_in_usecs; 269 unsigned int map_bits; 270 271 char *assignment_str[TRACING_MAP_VARS_MAX]; 272 unsigned int n_assignments; 273 274 char *action_str[HIST_ACTIONS_MAX]; 275 unsigned int n_actions; 276 277 struct var_defs var_defs; 278 }; 279 280 struct field_var { 281 struct hist_field *var; 282 struct hist_field *val; 283 }; 284 285 struct field_var_hist { 286 struct hist_trigger_data *hist_data; 287 char *cmd; 288 }; 289 290 struct hist_trigger_data { 291 struct hist_field *fields[HIST_FIELDS_MAX]; 292 unsigned int n_vals; 293 unsigned int n_keys; 294 unsigned int n_fields; 295 unsigned int n_vars; 296 unsigned int key_size; 297 struct tracing_map_sort_key sort_keys[TRACING_MAP_SORT_KEYS_MAX]; 298 unsigned int n_sort_keys; 299 struct trace_event_file *event_file; 300 struct hist_trigger_attrs *attrs; 301 struct tracing_map *map; 302 bool enable_timestamps; 303 bool remove; 304 struct hist_field *var_refs[TRACING_MAP_VARS_MAX]; 305 unsigned int n_var_refs; 306 307 struct action_data *actions[HIST_ACTIONS_MAX]; 308 unsigned int n_actions; 309 310 struct field_var *field_vars[SYNTH_FIELDS_MAX]; 311 unsigned int n_field_vars; 312 unsigned int n_field_var_str; 313 struct field_var_hist *field_var_hists[SYNTH_FIELDS_MAX]; 314 unsigned int n_field_var_hists; 315 316 struct field_var *max_vars[SYNTH_FIELDS_MAX]; 317 unsigned int n_max_vars; 318 unsigned int n_max_var_str; 319 }; 320 321 static int synth_event_create(int argc, const char **argv); 322 static int synth_event_show(struct seq_file *m, struct dyn_event *ev); 323 static int synth_event_release(struct dyn_event *ev); 324 static bool synth_event_is_busy(struct dyn_event *ev); 325 static bool synth_event_match(const char *system, const char *event, 326 struct dyn_event *ev); 327 328 static struct dyn_event_operations synth_event_ops = { 329 .create = synth_event_create, 330 .show = synth_event_show, 331 .is_busy = synth_event_is_busy, 332 .free = synth_event_release, 333 .match = synth_event_match, 334 }; 335 336 struct synth_field { 337 char *type; 338 char *name; 339 size_t size; 340 bool is_signed; 341 bool is_string; 342 }; 343 344 struct synth_event { 345 struct dyn_event devent; 346 int ref; 347 char *name; 348 struct synth_field **fields; 349 unsigned int n_fields; 350 unsigned int n_u64; 351 struct trace_event_class class; 352 struct trace_event_call call; 353 struct tracepoint *tp; 354 }; 355 356 static bool is_synth_event(struct dyn_event *ev) 357 { 358 return ev->ops == &synth_event_ops; 359 } 360 361 static struct synth_event *to_synth_event(struct dyn_event *ev) 362 { 363 return container_of(ev, struct synth_event, devent); 364 } 365 366 static bool synth_event_is_busy(struct dyn_event *ev) 367 { 368 struct synth_event *event = to_synth_event(ev); 369 370 return event->ref != 0; 371 } 372 373 static bool synth_event_match(const char *system, const char *event, 374 struct dyn_event *ev) 375 { 376 struct synth_event *sev = to_synth_event(ev); 377 378 return strcmp(sev->name, event) == 0 && 379 (!system || strcmp(system, SYNTH_SYSTEM) == 0); 380 } 381 382 struct action_data; 383 384 typedef void (*action_fn_t) (struct hist_trigger_data *hist_data, 385 struct tracing_map_elt *elt, void *rec, 386 struct ring_buffer_event *rbe, 387 struct action_data *data, u64 *var_ref_vals); 388 389 struct action_data { 390 action_fn_t fn; 391 unsigned int n_params; 392 char *params[SYNTH_FIELDS_MAX]; 393 394 union { 395 struct { 396 /* 397 * When a histogram trigger is hit, the values of any 398 * references to variables, including variables being passed 399 * as parameters to synthetic events, are collected into a 400 * var_ref_vals array. This var_ref_idx is the index of the 401 * first param in the array to be passed to the synthetic 402 * event invocation. 403 */ 404 unsigned int var_ref_idx; 405 char *match_event; 406 char *match_event_system; 407 char *synth_event_name; 408 struct synth_event *synth_event; 409 } onmatch; 410 411 struct { 412 char *var_str; 413 char *fn_name; 414 unsigned int max_var_ref_idx; 415 struct hist_field *max_var; 416 struct hist_field *var; 417 } onmax; 418 }; 419 }; 420 421 422 static char last_hist_cmd[MAX_FILTER_STR_VAL]; 423 static char hist_err_str[MAX_FILTER_STR_VAL]; 424 425 static void last_cmd_set(char *str) 426 { 427 if (!str) 428 return; 429 430 strncpy(last_hist_cmd, str, MAX_FILTER_STR_VAL - 1); 431 } 432 433 static void hist_err(char *str, char *var) 434 { 435 int maxlen = MAX_FILTER_STR_VAL - 1; 436 437 if (!str) 438 return; 439 440 if (strlen(hist_err_str)) 441 return; 442 443 if (!var) 444 var = ""; 445 446 if (strlen(hist_err_str) + strlen(str) + strlen(var) > maxlen) 447 return; 448 449 strcat(hist_err_str, str); 450 strcat(hist_err_str, var); 451 } 452 453 static void hist_err_event(char *str, char *system, char *event, char *var) 454 { 455 char err[MAX_FILTER_STR_VAL]; 456 457 if (system && var) 458 snprintf(err, MAX_FILTER_STR_VAL, "%s.%s.%s", system, event, var); 459 else if (system) 460 snprintf(err, MAX_FILTER_STR_VAL, "%s.%s", system, event); 461 else 462 strscpy(err, var, MAX_FILTER_STR_VAL); 463 464 hist_err(str, err); 465 } 466 467 static void hist_err_clear(void) 468 { 469 hist_err_str[0] = '\0'; 470 } 471 472 static bool have_hist_err(void) 473 { 474 if (strlen(hist_err_str)) 475 return true; 476 477 return false; 478 } 479 480 struct synth_trace_event { 481 struct trace_entry ent; 482 u64 fields[]; 483 }; 484 485 static int synth_event_define_fields(struct trace_event_call *call) 486 { 487 struct synth_trace_event trace; 488 int offset = offsetof(typeof(trace), fields); 489 struct synth_event *event = call->data; 490 unsigned int i, size, n_u64; 491 char *name, *type; 492 bool is_signed; 493 int ret = 0; 494 495 for (i = 0, n_u64 = 0; i < event->n_fields; i++) { 496 size = event->fields[i]->size; 497 is_signed = event->fields[i]->is_signed; 498 type = event->fields[i]->type; 499 name = event->fields[i]->name; 500 ret = trace_define_field(call, type, name, offset, size, 501 is_signed, FILTER_OTHER); 502 if (ret) 503 break; 504 505 if (event->fields[i]->is_string) { 506 offset += STR_VAR_LEN_MAX; 507 n_u64 += STR_VAR_LEN_MAX / sizeof(u64); 508 } else { 509 offset += sizeof(u64); 510 n_u64++; 511 } 512 } 513 514 event->n_u64 = n_u64; 515 516 return ret; 517 } 518 519 static bool synth_field_signed(char *type) 520 { 521 if (str_has_prefix(type, "u")) 522 return false; 523 524 return true; 525 } 526 527 static int synth_field_is_string(char *type) 528 { 529 if (strstr(type, "char[") != NULL) 530 return true; 531 532 return false; 533 } 534 535 static int synth_field_string_size(char *type) 536 { 537 char buf[4], *end, *start; 538 unsigned int len; 539 int size, err; 540 541 start = strstr(type, "char["); 542 if (start == NULL) 543 return -EINVAL; 544 start += sizeof("char[") - 1; 545 546 end = strchr(type, ']'); 547 if (!end || end < start) 548 return -EINVAL; 549 550 len = end - start; 551 if (len > 3) 552 return -EINVAL; 553 554 strncpy(buf, start, len); 555 buf[len] = '\0'; 556 557 err = kstrtouint(buf, 0, &size); 558 if (err) 559 return err; 560 561 if (size > STR_VAR_LEN_MAX) 562 return -EINVAL; 563 564 return size; 565 } 566 567 static int synth_field_size(char *type) 568 { 569 int size = 0; 570 571 if (strcmp(type, "s64") == 0) 572 size = sizeof(s64); 573 else if (strcmp(type, "u64") == 0) 574 size = sizeof(u64); 575 else if (strcmp(type, "s32") == 0) 576 size = sizeof(s32); 577 else if (strcmp(type, "u32") == 0) 578 size = sizeof(u32); 579 else if (strcmp(type, "s16") == 0) 580 size = sizeof(s16); 581 else if (strcmp(type, "u16") == 0) 582 size = sizeof(u16); 583 else if (strcmp(type, "s8") == 0) 584 size = sizeof(s8); 585 else if (strcmp(type, "u8") == 0) 586 size = sizeof(u8); 587 else if (strcmp(type, "char") == 0) 588 size = sizeof(char); 589 else if (strcmp(type, "unsigned char") == 0) 590 size = sizeof(unsigned char); 591 else if (strcmp(type, "int") == 0) 592 size = sizeof(int); 593 else if (strcmp(type, "unsigned int") == 0) 594 size = sizeof(unsigned int); 595 else if (strcmp(type, "long") == 0) 596 size = sizeof(long); 597 else if (strcmp(type, "unsigned long") == 0) 598 size = sizeof(unsigned long); 599 else if (strcmp(type, "pid_t") == 0) 600 size = sizeof(pid_t); 601 else if (synth_field_is_string(type)) 602 size = synth_field_string_size(type); 603 604 return size; 605 } 606 607 static const char *synth_field_fmt(char *type) 608 { 609 const char *fmt = "%llu"; 610 611 if (strcmp(type, "s64") == 0) 612 fmt = "%lld"; 613 else if (strcmp(type, "u64") == 0) 614 fmt = "%llu"; 615 else if (strcmp(type, "s32") == 0) 616 fmt = "%d"; 617 else if (strcmp(type, "u32") == 0) 618 fmt = "%u"; 619 else if (strcmp(type, "s16") == 0) 620 fmt = "%d"; 621 else if (strcmp(type, "u16") == 0) 622 fmt = "%u"; 623 else if (strcmp(type, "s8") == 0) 624 fmt = "%d"; 625 else if (strcmp(type, "u8") == 0) 626 fmt = "%u"; 627 else if (strcmp(type, "char") == 0) 628 fmt = "%d"; 629 else if (strcmp(type, "unsigned char") == 0) 630 fmt = "%u"; 631 else if (strcmp(type, "int") == 0) 632 fmt = "%d"; 633 else if (strcmp(type, "unsigned int") == 0) 634 fmt = "%u"; 635 else if (strcmp(type, "long") == 0) 636 fmt = "%ld"; 637 else if (strcmp(type, "unsigned long") == 0) 638 fmt = "%lu"; 639 else if (strcmp(type, "pid_t") == 0) 640 fmt = "%d"; 641 else if (synth_field_is_string(type)) 642 fmt = "%s"; 643 644 return fmt; 645 } 646 647 static enum print_line_t print_synth_event(struct trace_iterator *iter, 648 int flags, 649 struct trace_event *event) 650 { 651 struct trace_array *tr = iter->tr; 652 struct trace_seq *s = &iter->seq; 653 struct synth_trace_event *entry; 654 struct synth_event *se; 655 unsigned int i, n_u64; 656 char print_fmt[32]; 657 const char *fmt; 658 659 entry = (struct synth_trace_event *)iter->ent; 660 se = container_of(event, struct synth_event, call.event); 661 662 trace_seq_printf(s, "%s: ", se->name); 663 664 for (i = 0, n_u64 = 0; i < se->n_fields; i++) { 665 if (trace_seq_has_overflowed(s)) 666 goto end; 667 668 fmt = synth_field_fmt(se->fields[i]->type); 669 670 /* parameter types */ 671 if (tr->trace_flags & TRACE_ITER_VERBOSE) 672 trace_seq_printf(s, "%s ", fmt); 673 674 snprintf(print_fmt, sizeof(print_fmt), "%%s=%s%%s", fmt); 675 676 /* parameter values */ 677 if (se->fields[i]->is_string) { 678 trace_seq_printf(s, print_fmt, se->fields[i]->name, 679 (char *)&entry->fields[n_u64], 680 i == se->n_fields - 1 ? "" : " "); 681 n_u64 += STR_VAR_LEN_MAX / sizeof(u64); 682 } else { 683 trace_seq_printf(s, print_fmt, se->fields[i]->name, 684 entry->fields[n_u64], 685 i == se->n_fields - 1 ? "" : " "); 686 n_u64++; 687 } 688 } 689 end: 690 trace_seq_putc(s, '\n'); 691 692 return trace_handle_return(s); 693 } 694 695 static struct trace_event_functions synth_event_funcs = { 696 .trace = print_synth_event 697 }; 698 699 static notrace void trace_event_raw_event_synth(void *__data, 700 u64 *var_ref_vals, 701 unsigned int var_ref_idx) 702 { 703 struct trace_event_file *trace_file = __data; 704 struct synth_trace_event *entry; 705 struct trace_event_buffer fbuffer; 706 struct ring_buffer *buffer; 707 struct synth_event *event; 708 unsigned int i, n_u64; 709 int fields_size = 0; 710 711 event = trace_file->event_call->data; 712 713 if (trace_trigger_soft_disabled(trace_file)) 714 return; 715 716 fields_size = event->n_u64 * sizeof(u64); 717 718 /* 719 * Avoid ring buffer recursion detection, as this event 720 * is being performed within another event. 721 */ 722 buffer = trace_file->tr->trace_buffer.buffer; 723 ring_buffer_nest_start(buffer); 724 725 entry = trace_event_buffer_reserve(&fbuffer, trace_file, 726 sizeof(*entry) + fields_size); 727 if (!entry) 728 goto out; 729 730 for (i = 0, n_u64 = 0; i < event->n_fields; i++) { 731 if (event->fields[i]->is_string) { 732 char *str_val = (char *)(long)var_ref_vals[var_ref_idx + i]; 733 char *str_field = (char *)&entry->fields[n_u64]; 734 735 strscpy(str_field, str_val, STR_VAR_LEN_MAX); 736 n_u64 += STR_VAR_LEN_MAX / sizeof(u64); 737 } else { 738 entry->fields[n_u64] = var_ref_vals[var_ref_idx + i]; 739 n_u64++; 740 } 741 } 742 743 trace_event_buffer_commit(&fbuffer); 744 out: 745 ring_buffer_nest_end(buffer); 746 } 747 748 static void free_synth_event_print_fmt(struct trace_event_call *call) 749 { 750 if (call) { 751 kfree(call->print_fmt); 752 call->print_fmt = NULL; 753 } 754 } 755 756 static int __set_synth_event_print_fmt(struct synth_event *event, 757 char *buf, int len) 758 { 759 const char *fmt; 760 int pos = 0; 761 int i; 762 763 /* When len=0, we just calculate the needed length */ 764 #define LEN_OR_ZERO (len ? len - pos : 0) 765 766 pos += snprintf(buf + pos, LEN_OR_ZERO, "\""); 767 for (i = 0; i < event->n_fields; i++) { 768 fmt = synth_field_fmt(event->fields[i]->type); 769 pos += snprintf(buf + pos, LEN_OR_ZERO, "%s=%s%s", 770 event->fields[i]->name, fmt, 771 i == event->n_fields - 1 ? "" : ", "); 772 } 773 pos += snprintf(buf + pos, LEN_OR_ZERO, "\""); 774 775 for (i = 0; i < event->n_fields; i++) { 776 pos += snprintf(buf + pos, LEN_OR_ZERO, 777 ", REC->%s", event->fields[i]->name); 778 } 779 780 #undef LEN_OR_ZERO 781 782 /* return the length of print_fmt */ 783 return pos; 784 } 785 786 static int set_synth_event_print_fmt(struct trace_event_call *call) 787 { 788 struct synth_event *event = call->data; 789 char *print_fmt; 790 int len; 791 792 /* First: called with 0 length to calculate the needed length */ 793 len = __set_synth_event_print_fmt(event, NULL, 0); 794 795 print_fmt = kmalloc(len + 1, GFP_KERNEL); 796 if (!print_fmt) 797 return -ENOMEM; 798 799 /* Second: actually write the @print_fmt */ 800 __set_synth_event_print_fmt(event, print_fmt, len + 1); 801 call->print_fmt = print_fmt; 802 803 return 0; 804 } 805 806 static void free_synth_field(struct synth_field *field) 807 { 808 kfree(field->type); 809 kfree(field->name); 810 kfree(field); 811 } 812 813 static struct synth_field *parse_synth_field(int argc, const char **argv, 814 int *consumed) 815 { 816 struct synth_field *field; 817 const char *prefix = NULL, *field_type = argv[0], *field_name, *array; 818 int len, ret = 0; 819 820 if (field_type[0] == ';') 821 field_type++; 822 823 if (!strcmp(field_type, "unsigned")) { 824 if (argc < 3) 825 return ERR_PTR(-EINVAL); 826 prefix = "unsigned "; 827 field_type = argv[1]; 828 field_name = argv[2]; 829 *consumed = 3; 830 } else { 831 field_name = argv[1]; 832 *consumed = 2; 833 } 834 835 field = kzalloc(sizeof(*field), GFP_KERNEL); 836 if (!field) 837 return ERR_PTR(-ENOMEM); 838 839 len = strlen(field_name); 840 array = strchr(field_name, '['); 841 if (array) 842 len -= strlen(array); 843 else if (field_name[len - 1] == ';') 844 len--; 845 846 field->name = kmemdup_nul(field_name, len, GFP_KERNEL); 847 if (!field->name) { 848 ret = -ENOMEM; 849 goto free; 850 } 851 852 if (field_type[0] == ';') 853 field_type++; 854 len = strlen(field_type) + 1; 855 if (array) 856 len += strlen(array); 857 if (prefix) 858 len += strlen(prefix); 859 860 field->type = kzalloc(len, GFP_KERNEL); 861 if (!field->type) { 862 ret = -ENOMEM; 863 goto free; 864 } 865 if (prefix) 866 strcat(field->type, prefix); 867 strcat(field->type, field_type); 868 if (array) { 869 strcat(field->type, array); 870 if (field->type[len - 1] == ';') 871 field->type[len - 1] = '\0'; 872 } 873 874 field->size = synth_field_size(field->type); 875 if (!field->size) { 876 ret = -EINVAL; 877 goto free; 878 } 879 880 if (synth_field_is_string(field->type)) 881 field->is_string = true; 882 883 field->is_signed = synth_field_signed(field->type); 884 885 out: 886 return field; 887 free: 888 free_synth_field(field); 889 field = ERR_PTR(ret); 890 goto out; 891 } 892 893 static void free_synth_tracepoint(struct tracepoint *tp) 894 { 895 if (!tp) 896 return; 897 898 kfree(tp->name); 899 kfree(tp); 900 } 901 902 static struct tracepoint *alloc_synth_tracepoint(char *name) 903 { 904 struct tracepoint *tp; 905 906 tp = kzalloc(sizeof(*tp), GFP_KERNEL); 907 if (!tp) 908 return ERR_PTR(-ENOMEM); 909 910 tp->name = kstrdup(name, GFP_KERNEL); 911 if (!tp->name) { 912 kfree(tp); 913 return ERR_PTR(-ENOMEM); 914 } 915 916 return tp; 917 } 918 919 typedef void (*synth_probe_func_t) (void *__data, u64 *var_ref_vals, 920 unsigned int var_ref_idx); 921 922 static inline void trace_synth(struct synth_event *event, u64 *var_ref_vals, 923 unsigned int var_ref_idx) 924 { 925 struct tracepoint *tp = event->tp; 926 927 if (unlikely(atomic_read(&tp->key.enabled) > 0)) { 928 struct tracepoint_func *probe_func_ptr; 929 synth_probe_func_t probe_func; 930 void *__data; 931 932 if (!(cpu_online(raw_smp_processor_id()))) 933 return; 934 935 probe_func_ptr = rcu_dereference_sched((tp)->funcs); 936 if (probe_func_ptr) { 937 do { 938 probe_func = probe_func_ptr->func; 939 __data = probe_func_ptr->data; 940 probe_func(__data, var_ref_vals, var_ref_idx); 941 } while ((++probe_func_ptr)->func); 942 } 943 } 944 } 945 946 static struct synth_event *find_synth_event(const char *name) 947 { 948 struct dyn_event *pos; 949 struct synth_event *event; 950 951 for_each_dyn_event(pos) { 952 if (!is_synth_event(pos)) 953 continue; 954 event = to_synth_event(pos); 955 if (strcmp(event->name, name) == 0) 956 return event; 957 } 958 959 return NULL; 960 } 961 962 static int register_synth_event(struct synth_event *event) 963 { 964 struct trace_event_call *call = &event->call; 965 int ret = 0; 966 967 event->call.class = &event->class; 968 event->class.system = kstrdup(SYNTH_SYSTEM, GFP_KERNEL); 969 if (!event->class.system) { 970 ret = -ENOMEM; 971 goto out; 972 } 973 974 event->tp = alloc_synth_tracepoint(event->name); 975 if (IS_ERR(event->tp)) { 976 ret = PTR_ERR(event->tp); 977 event->tp = NULL; 978 goto out; 979 } 980 981 INIT_LIST_HEAD(&call->class->fields); 982 call->event.funcs = &synth_event_funcs; 983 call->class->define_fields = synth_event_define_fields; 984 985 ret = register_trace_event(&call->event); 986 if (!ret) { 987 ret = -ENODEV; 988 goto out; 989 } 990 call->flags = TRACE_EVENT_FL_TRACEPOINT; 991 call->class->reg = trace_event_reg; 992 call->class->probe = trace_event_raw_event_synth; 993 call->data = event; 994 call->tp = event->tp; 995 996 ret = trace_add_event_call(call); 997 if (ret) { 998 pr_warn("Failed to register synthetic event: %s\n", 999 trace_event_name(call)); 1000 goto err; 1001 } 1002 1003 ret = set_synth_event_print_fmt(call); 1004 if (ret < 0) { 1005 trace_remove_event_call(call); 1006 goto err; 1007 } 1008 out: 1009 return ret; 1010 err: 1011 unregister_trace_event(&call->event); 1012 goto out; 1013 } 1014 1015 static int unregister_synth_event(struct synth_event *event) 1016 { 1017 struct trace_event_call *call = &event->call; 1018 int ret; 1019 1020 ret = trace_remove_event_call(call); 1021 1022 return ret; 1023 } 1024 1025 static void free_synth_event(struct synth_event *event) 1026 { 1027 unsigned int i; 1028 1029 if (!event) 1030 return; 1031 1032 for (i = 0; i < event->n_fields; i++) 1033 free_synth_field(event->fields[i]); 1034 1035 kfree(event->fields); 1036 kfree(event->name); 1037 kfree(event->class.system); 1038 free_synth_tracepoint(event->tp); 1039 free_synth_event_print_fmt(&event->call); 1040 kfree(event); 1041 } 1042 1043 static struct synth_event *alloc_synth_event(const char *name, int n_fields, 1044 struct synth_field **fields) 1045 { 1046 struct synth_event *event; 1047 unsigned int i; 1048 1049 event = kzalloc(sizeof(*event), GFP_KERNEL); 1050 if (!event) { 1051 event = ERR_PTR(-ENOMEM); 1052 goto out; 1053 } 1054 1055 event->name = kstrdup(name, GFP_KERNEL); 1056 if (!event->name) { 1057 kfree(event); 1058 event = ERR_PTR(-ENOMEM); 1059 goto out; 1060 } 1061 1062 event->fields = kcalloc(n_fields, sizeof(*event->fields), GFP_KERNEL); 1063 if (!event->fields) { 1064 free_synth_event(event); 1065 event = ERR_PTR(-ENOMEM); 1066 goto out; 1067 } 1068 1069 dyn_event_init(&event->devent, &synth_event_ops); 1070 1071 for (i = 0; i < n_fields; i++) 1072 event->fields[i] = fields[i]; 1073 1074 event->n_fields = n_fields; 1075 out: 1076 return event; 1077 } 1078 1079 static void action_trace(struct hist_trigger_data *hist_data, 1080 struct tracing_map_elt *elt, void *rec, 1081 struct ring_buffer_event *rbe, 1082 struct action_data *data, u64 *var_ref_vals) 1083 { 1084 struct synth_event *event = data->onmatch.synth_event; 1085 1086 trace_synth(event, var_ref_vals, data->onmatch.var_ref_idx); 1087 } 1088 1089 struct hist_var_data { 1090 struct list_head list; 1091 struct hist_trigger_data *hist_data; 1092 }; 1093 1094 static int __create_synth_event(int argc, const char *name, const char **argv) 1095 { 1096 struct synth_field *field, *fields[SYNTH_FIELDS_MAX]; 1097 struct synth_event *event = NULL; 1098 int i, consumed = 0, n_fields = 0, ret = 0; 1099 1100 /* 1101 * Argument syntax: 1102 * - Add synthetic event: <event_name> field[;field] ... 1103 * - Remove synthetic event: !<event_name> field[;field] ... 1104 * where 'field' = type field_name 1105 */ 1106 1107 if (name[0] == '\0' || argc < 1) 1108 return -EINVAL; 1109 1110 mutex_lock(&event_mutex); 1111 1112 event = find_synth_event(name); 1113 if (event) { 1114 ret = -EEXIST; 1115 goto out; 1116 } 1117 1118 for (i = 0; i < argc - 1; i++) { 1119 if (strcmp(argv[i], ";") == 0) 1120 continue; 1121 if (n_fields == SYNTH_FIELDS_MAX) { 1122 ret = -EINVAL; 1123 goto err; 1124 } 1125 1126 field = parse_synth_field(argc - i, &argv[i], &consumed); 1127 if (IS_ERR(field)) { 1128 ret = PTR_ERR(field); 1129 goto err; 1130 } 1131 fields[n_fields++] = field; 1132 i += consumed - 1; 1133 } 1134 1135 if (i < argc && strcmp(argv[i], ";") != 0) { 1136 ret = -EINVAL; 1137 goto err; 1138 } 1139 1140 event = alloc_synth_event(name, n_fields, fields); 1141 if (IS_ERR(event)) { 1142 ret = PTR_ERR(event); 1143 event = NULL; 1144 goto err; 1145 } 1146 ret = register_synth_event(event); 1147 if (!ret) 1148 dyn_event_add(&event->devent); 1149 else 1150 free_synth_event(event); 1151 out: 1152 mutex_unlock(&event_mutex); 1153 1154 return ret; 1155 err: 1156 for (i = 0; i < n_fields; i++) 1157 free_synth_field(fields[i]); 1158 1159 goto out; 1160 } 1161 1162 static int create_or_delete_synth_event(int argc, char **argv) 1163 { 1164 const char *name = argv[0]; 1165 struct synth_event *event = NULL; 1166 int ret; 1167 1168 /* trace_run_command() ensures argc != 0 */ 1169 if (name[0] == '!') { 1170 mutex_lock(&event_mutex); 1171 event = find_synth_event(name + 1); 1172 if (event) { 1173 if (event->ref) 1174 ret = -EBUSY; 1175 else { 1176 ret = unregister_synth_event(event); 1177 if (!ret) { 1178 dyn_event_remove(&event->devent); 1179 free_synth_event(event); 1180 } 1181 } 1182 } else 1183 ret = -ENOENT; 1184 mutex_unlock(&event_mutex); 1185 return ret; 1186 } 1187 1188 ret = __create_synth_event(argc - 1, name, (const char **)argv + 1); 1189 return ret == -ECANCELED ? -EINVAL : ret; 1190 } 1191 1192 static int synth_event_create(int argc, const char **argv) 1193 { 1194 const char *name = argv[0]; 1195 int len; 1196 1197 if (name[0] != 's' || name[1] != ':') 1198 return -ECANCELED; 1199 name += 2; 1200 1201 /* This interface accepts group name prefix */ 1202 if (strchr(name, '/')) { 1203 len = sizeof(SYNTH_SYSTEM "/") - 1; 1204 if (strncmp(name, SYNTH_SYSTEM "/", len)) 1205 return -EINVAL; 1206 name += len; 1207 } 1208 return __create_synth_event(argc - 1, name, argv + 1); 1209 } 1210 1211 static int synth_event_release(struct dyn_event *ev) 1212 { 1213 struct synth_event *event = to_synth_event(ev); 1214 int ret; 1215 1216 if (event->ref) 1217 return -EBUSY; 1218 1219 ret = unregister_synth_event(event); 1220 if (ret) 1221 return ret; 1222 1223 dyn_event_remove(ev); 1224 free_synth_event(event); 1225 return 0; 1226 } 1227 1228 static int __synth_event_show(struct seq_file *m, struct synth_event *event) 1229 { 1230 struct synth_field *field; 1231 unsigned int i; 1232 1233 seq_printf(m, "%s\t", event->name); 1234 1235 for (i = 0; i < event->n_fields; i++) { 1236 field = event->fields[i]; 1237 1238 /* parameter values */ 1239 seq_printf(m, "%s %s%s", field->type, field->name, 1240 i == event->n_fields - 1 ? "" : "; "); 1241 } 1242 1243 seq_putc(m, '\n'); 1244 1245 return 0; 1246 } 1247 1248 static int synth_event_show(struct seq_file *m, struct dyn_event *ev) 1249 { 1250 struct synth_event *event = to_synth_event(ev); 1251 1252 seq_printf(m, "s:%s/", event->class.system); 1253 1254 return __synth_event_show(m, event); 1255 } 1256 1257 static int synth_events_seq_show(struct seq_file *m, void *v) 1258 { 1259 struct dyn_event *ev = v; 1260 1261 if (!is_synth_event(ev)) 1262 return 0; 1263 1264 return __synth_event_show(m, to_synth_event(ev)); 1265 } 1266 1267 static const struct seq_operations synth_events_seq_op = { 1268 .start = dyn_event_seq_start, 1269 .next = dyn_event_seq_next, 1270 .stop = dyn_event_seq_stop, 1271 .show = synth_events_seq_show, 1272 }; 1273 1274 static int synth_events_open(struct inode *inode, struct file *file) 1275 { 1276 int ret; 1277 1278 if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) { 1279 ret = dyn_events_release_all(&synth_event_ops); 1280 if (ret < 0) 1281 return ret; 1282 } 1283 1284 return seq_open(file, &synth_events_seq_op); 1285 } 1286 1287 static ssize_t synth_events_write(struct file *file, 1288 const char __user *buffer, 1289 size_t count, loff_t *ppos) 1290 { 1291 return trace_parse_run_command(file, buffer, count, ppos, 1292 create_or_delete_synth_event); 1293 } 1294 1295 static const struct file_operations synth_events_fops = { 1296 .open = synth_events_open, 1297 .write = synth_events_write, 1298 .read = seq_read, 1299 .llseek = seq_lseek, 1300 .release = seq_release, 1301 }; 1302 1303 static u64 hist_field_timestamp(struct hist_field *hist_field, 1304 struct tracing_map_elt *elt, 1305 struct ring_buffer_event *rbe, 1306 void *event) 1307 { 1308 struct hist_trigger_data *hist_data = hist_field->hist_data; 1309 struct trace_array *tr = hist_data->event_file->tr; 1310 1311 u64 ts = ring_buffer_event_time_stamp(rbe); 1312 1313 if (hist_data->attrs->ts_in_usecs && trace_clock_in_ns(tr)) 1314 ts = ns2usecs(ts); 1315 1316 return ts; 1317 } 1318 1319 static u64 hist_field_cpu(struct hist_field *hist_field, 1320 struct tracing_map_elt *elt, 1321 struct ring_buffer_event *rbe, 1322 void *event) 1323 { 1324 int cpu = smp_processor_id(); 1325 1326 return cpu; 1327 } 1328 1329 /** 1330 * check_field_for_var_ref - Check if a VAR_REF field references a variable 1331 * @hist_field: The VAR_REF field to check 1332 * @var_data: The hist trigger that owns the variable 1333 * @var_idx: The trigger variable identifier 1334 * 1335 * Check the given VAR_REF field to see whether or not it references 1336 * the given variable associated with the given trigger. 1337 * 1338 * Return: The VAR_REF field if it does reference the variable, NULL if not 1339 */ 1340 static struct hist_field * 1341 check_field_for_var_ref(struct hist_field *hist_field, 1342 struct hist_trigger_data *var_data, 1343 unsigned int var_idx) 1344 { 1345 WARN_ON(!(hist_field && hist_field->flags & HIST_FIELD_FL_VAR_REF)); 1346 1347 if (hist_field && hist_field->var.idx == var_idx && 1348 hist_field->var.hist_data == var_data) 1349 return hist_field; 1350 1351 return NULL; 1352 } 1353 1354 /** 1355 * find_var_ref - Check if a trigger has a reference to a trigger variable 1356 * @hist_data: The hist trigger that might have a reference to the variable 1357 * @var_data: The hist trigger that owns the variable 1358 * @var_idx: The trigger variable identifier 1359 * 1360 * Check the list of var_refs[] on the first hist trigger to see 1361 * whether any of them are references to the variable on the second 1362 * trigger. 1363 * 1364 * Return: The VAR_REF field referencing the variable if so, NULL if not 1365 */ 1366 static struct hist_field *find_var_ref(struct hist_trigger_data *hist_data, 1367 struct hist_trigger_data *var_data, 1368 unsigned int var_idx) 1369 { 1370 struct hist_field *hist_field; 1371 unsigned int i; 1372 1373 for (i = 0; i < hist_data->n_var_refs; i++) { 1374 hist_field = hist_data->var_refs[i]; 1375 if (check_field_for_var_ref(hist_field, var_data, var_idx)) 1376 return hist_field; 1377 } 1378 1379 return NULL; 1380 } 1381 1382 /** 1383 * find_any_var_ref - Check if there is a reference to a given trigger variable 1384 * @hist_data: The hist trigger 1385 * @var_idx: The trigger variable identifier 1386 * 1387 * Check to see whether the given variable is currently referenced by 1388 * any other trigger. 1389 * 1390 * The trigger the variable is defined on is explicitly excluded - the 1391 * assumption being that a self-reference doesn't prevent a trigger 1392 * from being removed. 1393 * 1394 * Return: The VAR_REF field referencing the variable if so, NULL if not 1395 */ 1396 static struct hist_field *find_any_var_ref(struct hist_trigger_data *hist_data, 1397 unsigned int var_idx) 1398 { 1399 struct trace_array *tr = hist_data->event_file->tr; 1400 struct hist_field *found = NULL; 1401 struct hist_var_data *var_data; 1402 1403 list_for_each_entry(var_data, &tr->hist_vars, list) { 1404 if (var_data->hist_data == hist_data) 1405 continue; 1406 found = find_var_ref(var_data->hist_data, hist_data, var_idx); 1407 if (found) 1408 break; 1409 } 1410 1411 return found; 1412 } 1413 1414 /** 1415 * check_var_refs - Check if there is a reference to any of trigger's variables 1416 * @hist_data: The hist trigger 1417 * 1418 * A trigger can define one or more variables. If any one of them is 1419 * currently referenced by any other trigger, this function will 1420 * determine that. 1421 1422 * Typically used to determine whether or not a trigger can be removed 1423 * - if there are any references to a trigger's variables, it cannot. 1424 * 1425 * Return: True if there is a reference to any of trigger's variables 1426 */ 1427 static bool check_var_refs(struct hist_trigger_data *hist_data) 1428 { 1429 struct hist_field *field; 1430 bool found = false; 1431 int i; 1432 1433 for_each_hist_field(i, hist_data) { 1434 field = hist_data->fields[i]; 1435 if (field && field->flags & HIST_FIELD_FL_VAR) { 1436 if (find_any_var_ref(hist_data, field->var.idx)) { 1437 found = true; 1438 break; 1439 } 1440 } 1441 } 1442 1443 return found; 1444 } 1445 1446 static struct hist_var_data *find_hist_vars(struct hist_trigger_data *hist_data) 1447 { 1448 struct trace_array *tr = hist_data->event_file->tr; 1449 struct hist_var_data *var_data, *found = NULL; 1450 1451 list_for_each_entry(var_data, &tr->hist_vars, list) { 1452 if (var_data->hist_data == hist_data) { 1453 found = var_data; 1454 break; 1455 } 1456 } 1457 1458 return found; 1459 } 1460 1461 static bool field_has_hist_vars(struct hist_field *hist_field, 1462 unsigned int level) 1463 { 1464 int i; 1465 1466 if (level > 3) 1467 return false; 1468 1469 if (!hist_field) 1470 return false; 1471 1472 if (hist_field->flags & HIST_FIELD_FL_VAR || 1473 hist_field->flags & HIST_FIELD_FL_VAR_REF) 1474 return true; 1475 1476 for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++) { 1477 struct hist_field *operand; 1478 1479 operand = hist_field->operands[i]; 1480 if (field_has_hist_vars(operand, level + 1)) 1481 return true; 1482 } 1483 1484 return false; 1485 } 1486 1487 static bool has_hist_vars(struct hist_trigger_data *hist_data) 1488 { 1489 struct hist_field *hist_field; 1490 int i; 1491 1492 for_each_hist_field(i, hist_data) { 1493 hist_field = hist_data->fields[i]; 1494 if (field_has_hist_vars(hist_field, 0)) 1495 return true; 1496 } 1497 1498 return false; 1499 } 1500 1501 static int save_hist_vars(struct hist_trigger_data *hist_data) 1502 { 1503 struct trace_array *tr = hist_data->event_file->tr; 1504 struct hist_var_data *var_data; 1505 1506 var_data = find_hist_vars(hist_data); 1507 if (var_data) 1508 return 0; 1509 1510 if (trace_array_get(tr) < 0) 1511 return -ENODEV; 1512 1513 var_data = kzalloc(sizeof(*var_data), GFP_KERNEL); 1514 if (!var_data) { 1515 trace_array_put(tr); 1516 return -ENOMEM; 1517 } 1518 1519 var_data->hist_data = hist_data; 1520 list_add(&var_data->list, &tr->hist_vars); 1521 1522 return 0; 1523 } 1524 1525 static void remove_hist_vars(struct hist_trigger_data *hist_data) 1526 { 1527 struct trace_array *tr = hist_data->event_file->tr; 1528 struct hist_var_data *var_data; 1529 1530 var_data = find_hist_vars(hist_data); 1531 if (!var_data) 1532 return; 1533 1534 if (WARN_ON(check_var_refs(hist_data))) 1535 return; 1536 1537 list_del(&var_data->list); 1538 1539 kfree(var_data); 1540 1541 trace_array_put(tr); 1542 } 1543 1544 static struct hist_field *find_var_field(struct hist_trigger_data *hist_data, 1545 const char *var_name) 1546 { 1547 struct hist_field *hist_field, *found = NULL; 1548 int i; 1549 1550 for_each_hist_field(i, hist_data) { 1551 hist_field = hist_data->fields[i]; 1552 if (hist_field && hist_field->flags & HIST_FIELD_FL_VAR && 1553 strcmp(hist_field->var.name, var_name) == 0) { 1554 found = hist_field; 1555 break; 1556 } 1557 } 1558 1559 return found; 1560 } 1561 1562 static struct hist_field *find_var(struct hist_trigger_data *hist_data, 1563 struct trace_event_file *file, 1564 const char *var_name) 1565 { 1566 struct hist_trigger_data *test_data; 1567 struct event_trigger_data *test; 1568 struct hist_field *hist_field; 1569 1570 hist_field = find_var_field(hist_data, var_name); 1571 if (hist_field) 1572 return hist_field; 1573 1574 list_for_each_entry_rcu(test, &file->triggers, list) { 1575 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 1576 test_data = test->private_data; 1577 hist_field = find_var_field(test_data, var_name); 1578 if (hist_field) 1579 return hist_field; 1580 } 1581 } 1582 1583 return NULL; 1584 } 1585 1586 static struct trace_event_file *find_var_file(struct trace_array *tr, 1587 char *system, 1588 char *event_name, 1589 char *var_name) 1590 { 1591 struct hist_trigger_data *var_hist_data; 1592 struct hist_var_data *var_data; 1593 struct trace_event_file *file, *found = NULL; 1594 1595 if (system) 1596 return find_event_file(tr, system, event_name); 1597 1598 list_for_each_entry(var_data, &tr->hist_vars, list) { 1599 var_hist_data = var_data->hist_data; 1600 file = var_hist_data->event_file; 1601 if (file == found) 1602 continue; 1603 1604 if (find_var_field(var_hist_data, var_name)) { 1605 if (found) { 1606 hist_err_event("Variable name not unique, need to use fully qualified name (subsys.event.var) for variable: ", system, event_name, var_name); 1607 return NULL; 1608 } 1609 1610 found = file; 1611 } 1612 } 1613 1614 return found; 1615 } 1616 1617 static struct hist_field *find_file_var(struct trace_event_file *file, 1618 const char *var_name) 1619 { 1620 struct hist_trigger_data *test_data; 1621 struct event_trigger_data *test; 1622 struct hist_field *hist_field; 1623 1624 list_for_each_entry_rcu(test, &file->triggers, list) { 1625 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 1626 test_data = test->private_data; 1627 hist_field = find_var_field(test_data, var_name); 1628 if (hist_field) 1629 return hist_field; 1630 } 1631 } 1632 1633 return NULL; 1634 } 1635 1636 static struct hist_field * 1637 find_match_var(struct hist_trigger_data *hist_data, char *var_name) 1638 { 1639 struct trace_array *tr = hist_data->event_file->tr; 1640 struct hist_field *hist_field, *found = NULL; 1641 struct trace_event_file *file; 1642 unsigned int i; 1643 1644 for (i = 0; i < hist_data->n_actions; i++) { 1645 struct action_data *data = hist_data->actions[i]; 1646 1647 if (data->fn == action_trace) { 1648 char *system = data->onmatch.match_event_system; 1649 char *event_name = data->onmatch.match_event; 1650 1651 file = find_var_file(tr, system, event_name, var_name); 1652 if (!file) 1653 continue; 1654 hist_field = find_file_var(file, var_name); 1655 if (hist_field) { 1656 if (found) { 1657 hist_err_event("Variable name not unique, need to use fully qualified name (subsys.event.var) for variable: ", system, event_name, var_name); 1658 return ERR_PTR(-EINVAL); 1659 } 1660 1661 found = hist_field; 1662 } 1663 } 1664 } 1665 return found; 1666 } 1667 1668 static struct hist_field *find_event_var(struct hist_trigger_data *hist_data, 1669 char *system, 1670 char *event_name, 1671 char *var_name) 1672 { 1673 struct trace_array *tr = hist_data->event_file->tr; 1674 struct hist_field *hist_field = NULL; 1675 struct trace_event_file *file; 1676 1677 if (!system || !event_name) { 1678 hist_field = find_match_var(hist_data, var_name); 1679 if (IS_ERR(hist_field)) 1680 return NULL; 1681 if (hist_field) 1682 return hist_field; 1683 } 1684 1685 file = find_var_file(tr, system, event_name, var_name); 1686 if (!file) 1687 return NULL; 1688 1689 hist_field = find_file_var(file, var_name); 1690 1691 return hist_field; 1692 } 1693 1694 struct hist_elt_data { 1695 char *comm; 1696 u64 *var_ref_vals; 1697 char *field_var_str[SYNTH_FIELDS_MAX]; 1698 }; 1699 1700 static u64 hist_field_var_ref(struct hist_field *hist_field, 1701 struct tracing_map_elt *elt, 1702 struct ring_buffer_event *rbe, 1703 void *event) 1704 { 1705 struct hist_elt_data *elt_data; 1706 u64 var_val = 0; 1707 1708 elt_data = elt->private_data; 1709 var_val = elt_data->var_ref_vals[hist_field->var_ref_idx]; 1710 1711 return var_val; 1712 } 1713 1714 static bool resolve_var_refs(struct hist_trigger_data *hist_data, void *key, 1715 u64 *var_ref_vals, bool self) 1716 { 1717 struct hist_trigger_data *var_data; 1718 struct tracing_map_elt *var_elt; 1719 struct hist_field *hist_field; 1720 unsigned int i, var_idx; 1721 bool resolved = true; 1722 u64 var_val = 0; 1723 1724 for (i = 0; i < hist_data->n_var_refs; i++) { 1725 hist_field = hist_data->var_refs[i]; 1726 var_idx = hist_field->var.idx; 1727 var_data = hist_field->var.hist_data; 1728 1729 if (var_data == NULL) { 1730 resolved = false; 1731 break; 1732 } 1733 1734 if ((self && var_data != hist_data) || 1735 (!self && var_data == hist_data)) 1736 continue; 1737 1738 var_elt = tracing_map_lookup(var_data->map, key); 1739 if (!var_elt) { 1740 resolved = false; 1741 break; 1742 } 1743 1744 if (!tracing_map_var_set(var_elt, var_idx)) { 1745 resolved = false; 1746 break; 1747 } 1748 1749 if (self || !hist_field->read_once) 1750 var_val = tracing_map_read_var(var_elt, var_idx); 1751 else 1752 var_val = tracing_map_read_var_once(var_elt, var_idx); 1753 1754 var_ref_vals[i] = var_val; 1755 } 1756 1757 return resolved; 1758 } 1759 1760 static const char *hist_field_name(struct hist_field *field, 1761 unsigned int level) 1762 { 1763 const char *field_name = ""; 1764 1765 if (level > 1) 1766 return field_name; 1767 1768 if (field->field) 1769 field_name = field->field->name; 1770 else if (field->flags & HIST_FIELD_FL_LOG2 || 1771 field->flags & HIST_FIELD_FL_ALIAS) 1772 field_name = hist_field_name(field->operands[0], ++level); 1773 else if (field->flags & HIST_FIELD_FL_CPU) 1774 field_name = "cpu"; 1775 else if (field->flags & HIST_FIELD_FL_EXPR || 1776 field->flags & HIST_FIELD_FL_VAR_REF) { 1777 if (field->system) { 1778 static char full_name[MAX_FILTER_STR_VAL]; 1779 1780 strcat(full_name, field->system); 1781 strcat(full_name, "."); 1782 strcat(full_name, field->event_name); 1783 strcat(full_name, "."); 1784 strcat(full_name, field->name); 1785 field_name = full_name; 1786 } else 1787 field_name = field->name; 1788 } else if (field->flags & HIST_FIELD_FL_TIMESTAMP) 1789 field_name = "common_timestamp"; 1790 1791 if (field_name == NULL) 1792 field_name = ""; 1793 1794 return field_name; 1795 } 1796 1797 static hist_field_fn_t select_value_fn(int field_size, int field_is_signed) 1798 { 1799 hist_field_fn_t fn = NULL; 1800 1801 switch (field_size) { 1802 case 8: 1803 if (field_is_signed) 1804 fn = hist_field_s64; 1805 else 1806 fn = hist_field_u64; 1807 break; 1808 case 4: 1809 if (field_is_signed) 1810 fn = hist_field_s32; 1811 else 1812 fn = hist_field_u32; 1813 break; 1814 case 2: 1815 if (field_is_signed) 1816 fn = hist_field_s16; 1817 else 1818 fn = hist_field_u16; 1819 break; 1820 case 1: 1821 if (field_is_signed) 1822 fn = hist_field_s8; 1823 else 1824 fn = hist_field_u8; 1825 break; 1826 } 1827 1828 return fn; 1829 } 1830 1831 static int parse_map_size(char *str) 1832 { 1833 unsigned long size, map_bits; 1834 int ret; 1835 1836 strsep(&str, "="); 1837 if (!str) { 1838 ret = -EINVAL; 1839 goto out; 1840 } 1841 1842 ret = kstrtoul(str, 0, &size); 1843 if (ret) 1844 goto out; 1845 1846 map_bits = ilog2(roundup_pow_of_two(size)); 1847 if (map_bits < TRACING_MAP_BITS_MIN || 1848 map_bits > TRACING_MAP_BITS_MAX) 1849 ret = -EINVAL; 1850 else 1851 ret = map_bits; 1852 out: 1853 return ret; 1854 } 1855 1856 static void destroy_hist_trigger_attrs(struct hist_trigger_attrs *attrs) 1857 { 1858 unsigned int i; 1859 1860 if (!attrs) 1861 return; 1862 1863 for (i = 0; i < attrs->n_assignments; i++) 1864 kfree(attrs->assignment_str[i]); 1865 1866 for (i = 0; i < attrs->n_actions; i++) 1867 kfree(attrs->action_str[i]); 1868 1869 kfree(attrs->name); 1870 kfree(attrs->sort_key_str); 1871 kfree(attrs->keys_str); 1872 kfree(attrs->vals_str); 1873 kfree(attrs->clock); 1874 kfree(attrs); 1875 } 1876 1877 static int parse_action(char *str, struct hist_trigger_attrs *attrs) 1878 { 1879 int ret = -EINVAL; 1880 1881 if (attrs->n_actions >= HIST_ACTIONS_MAX) 1882 return ret; 1883 1884 if ((str_has_prefix(str, "onmatch(")) || 1885 (str_has_prefix(str, "onmax("))) { 1886 attrs->action_str[attrs->n_actions] = kstrdup(str, GFP_KERNEL); 1887 if (!attrs->action_str[attrs->n_actions]) { 1888 ret = -ENOMEM; 1889 return ret; 1890 } 1891 attrs->n_actions++; 1892 ret = 0; 1893 } 1894 1895 return ret; 1896 } 1897 1898 static int parse_assignment(char *str, struct hist_trigger_attrs *attrs) 1899 { 1900 int ret = 0; 1901 1902 if ((str_has_prefix(str, "key=")) || 1903 (str_has_prefix(str, "keys="))) { 1904 attrs->keys_str = kstrdup(str, GFP_KERNEL); 1905 if (!attrs->keys_str) { 1906 ret = -ENOMEM; 1907 goto out; 1908 } 1909 } else if ((str_has_prefix(str, "val=")) || 1910 (str_has_prefix(str, "vals=")) || 1911 (str_has_prefix(str, "values="))) { 1912 attrs->vals_str = kstrdup(str, GFP_KERNEL); 1913 if (!attrs->vals_str) { 1914 ret = -ENOMEM; 1915 goto out; 1916 } 1917 } else if (str_has_prefix(str, "sort=")) { 1918 attrs->sort_key_str = kstrdup(str, GFP_KERNEL); 1919 if (!attrs->sort_key_str) { 1920 ret = -ENOMEM; 1921 goto out; 1922 } 1923 } else if (str_has_prefix(str, "name=")) { 1924 attrs->name = kstrdup(str, GFP_KERNEL); 1925 if (!attrs->name) { 1926 ret = -ENOMEM; 1927 goto out; 1928 } 1929 } else if (str_has_prefix(str, "clock=")) { 1930 strsep(&str, "="); 1931 if (!str) { 1932 ret = -EINVAL; 1933 goto out; 1934 } 1935 1936 str = strstrip(str); 1937 attrs->clock = kstrdup(str, GFP_KERNEL); 1938 if (!attrs->clock) { 1939 ret = -ENOMEM; 1940 goto out; 1941 } 1942 } else if (str_has_prefix(str, "size=")) { 1943 int map_bits = parse_map_size(str); 1944 1945 if (map_bits < 0) { 1946 ret = map_bits; 1947 goto out; 1948 } 1949 attrs->map_bits = map_bits; 1950 } else { 1951 char *assignment; 1952 1953 if (attrs->n_assignments == TRACING_MAP_VARS_MAX) { 1954 hist_err("Too many variables defined: ", str); 1955 ret = -EINVAL; 1956 goto out; 1957 } 1958 1959 assignment = kstrdup(str, GFP_KERNEL); 1960 if (!assignment) { 1961 ret = -ENOMEM; 1962 goto out; 1963 } 1964 1965 attrs->assignment_str[attrs->n_assignments++] = assignment; 1966 } 1967 out: 1968 return ret; 1969 } 1970 1971 static struct hist_trigger_attrs *parse_hist_trigger_attrs(char *trigger_str) 1972 { 1973 struct hist_trigger_attrs *attrs; 1974 int ret = 0; 1975 1976 attrs = kzalloc(sizeof(*attrs), GFP_KERNEL); 1977 if (!attrs) 1978 return ERR_PTR(-ENOMEM); 1979 1980 while (trigger_str) { 1981 char *str = strsep(&trigger_str, ":"); 1982 1983 if (strchr(str, '=')) { 1984 ret = parse_assignment(str, attrs); 1985 if (ret) 1986 goto free; 1987 } else if (strcmp(str, "pause") == 0) 1988 attrs->pause = true; 1989 else if ((strcmp(str, "cont") == 0) || 1990 (strcmp(str, "continue") == 0)) 1991 attrs->cont = true; 1992 else if (strcmp(str, "clear") == 0) 1993 attrs->clear = true; 1994 else { 1995 ret = parse_action(str, attrs); 1996 if (ret) 1997 goto free; 1998 } 1999 } 2000 2001 if (!attrs->keys_str) { 2002 ret = -EINVAL; 2003 goto free; 2004 } 2005 2006 if (!attrs->clock) { 2007 attrs->clock = kstrdup("global", GFP_KERNEL); 2008 if (!attrs->clock) { 2009 ret = -ENOMEM; 2010 goto free; 2011 } 2012 } 2013 2014 return attrs; 2015 free: 2016 destroy_hist_trigger_attrs(attrs); 2017 2018 return ERR_PTR(ret); 2019 } 2020 2021 static inline void save_comm(char *comm, struct task_struct *task) 2022 { 2023 if (!task->pid) { 2024 strcpy(comm, "<idle>"); 2025 return; 2026 } 2027 2028 if (WARN_ON_ONCE(task->pid < 0)) { 2029 strcpy(comm, "<XXX>"); 2030 return; 2031 } 2032 2033 memcpy(comm, task->comm, TASK_COMM_LEN); 2034 } 2035 2036 static void hist_elt_data_free(struct hist_elt_data *elt_data) 2037 { 2038 unsigned int i; 2039 2040 for (i = 0; i < SYNTH_FIELDS_MAX; i++) 2041 kfree(elt_data->field_var_str[i]); 2042 2043 kfree(elt_data->comm); 2044 kfree(elt_data); 2045 } 2046 2047 static void hist_trigger_elt_data_free(struct tracing_map_elt *elt) 2048 { 2049 struct hist_elt_data *elt_data = elt->private_data; 2050 2051 hist_elt_data_free(elt_data); 2052 } 2053 2054 static int hist_trigger_elt_data_alloc(struct tracing_map_elt *elt) 2055 { 2056 struct hist_trigger_data *hist_data = elt->map->private_data; 2057 unsigned int size = TASK_COMM_LEN; 2058 struct hist_elt_data *elt_data; 2059 struct hist_field *key_field; 2060 unsigned int i, n_str; 2061 2062 elt_data = kzalloc(sizeof(*elt_data), GFP_KERNEL); 2063 if (!elt_data) 2064 return -ENOMEM; 2065 2066 for_each_hist_key_field(i, hist_data) { 2067 key_field = hist_data->fields[i]; 2068 2069 if (key_field->flags & HIST_FIELD_FL_EXECNAME) { 2070 elt_data->comm = kzalloc(size, GFP_KERNEL); 2071 if (!elt_data->comm) { 2072 kfree(elt_data); 2073 return -ENOMEM; 2074 } 2075 break; 2076 } 2077 } 2078 2079 n_str = hist_data->n_field_var_str + hist_data->n_max_var_str; 2080 2081 size = STR_VAR_LEN_MAX; 2082 2083 for (i = 0; i < n_str; i++) { 2084 elt_data->field_var_str[i] = kzalloc(size, GFP_KERNEL); 2085 if (!elt_data->field_var_str[i]) { 2086 hist_elt_data_free(elt_data); 2087 return -ENOMEM; 2088 } 2089 } 2090 2091 elt->private_data = elt_data; 2092 2093 return 0; 2094 } 2095 2096 static void hist_trigger_elt_data_init(struct tracing_map_elt *elt) 2097 { 2098 struct hist_elt_data *elt_data = elt->private_data; 2099 2100 if (elt_data->comm) 2101 save_comm(elt_data->comm, current); 2102 } 2103 2104 static const struct tracing_map_ops hist_trigger_elt_data_ops = { 2105 .elt_alloc = hist_trigger_elt_data_alloc, 2106 .elt_free = hist_trigger_elt_data_free, 2107 .elt_init = hist_trigger_elt_data_init, 2108 }; 2109 2110 static const char *get_hist_field_flags(struct hist_field *hist_field) 2111 { 2112 const char *flags_str = NULL; 2113 2114 if (hist_field->flags & HIST_FIELD_FL_HEX) 2115 flags_str = "hex"; 2116 else if (hist_field->flags & HIST_FIELD_FL_SYM) 2117 flags_str = "sym"; 2118 else if (hist_field->flags & HIST_FIELD_FL_SYM_OFFSET) 2119 flags_str = "sym-offset"; 2120 else if (hist_field->flags & HIST_FIELD_FL_EXECNAME) 2121 flags_str = "execname"; 2122 else if (hist_field->flags & HIST_FIELD_FL_SYSCALL) 2123 flags_str = "syscall"; 2124 else if (hist_field->flags & HIST_FIELD_FL_LOG2) 2125 flags_str = "log2"; 2126 else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP_USECS) 2127 flags_str = "usecs"; 2128 2129 return flags_str; 2130 } 2131 2132 static void expr_field_str(struct hist_field *field, char *expr) 2133 { 2134 if (field->flags & HIST_FIELD_FL_VAR_REF) 2135 strcat(expr, "$"); 2136 2137 strcat(expr, hist_field_name(field, 0)); 2138 2139 if (field->flags && !(field->flags & HIST_FIELD_FL_VAR_REF)) { 2140 const char *flags_str = get_hist_field_flags(field); 2141 2142 if (flags_str) { 2143 strcat(expr, "."); 2144 strcat(expr, flags_str); 2145 } 2146 } 2147 } 2148 2149 static char *expr_str(struct hist_field *field, unsigned int level) 2150 { 2151 char *expr; 2152 2153 if (level > 1) 2154 return NULL; 2155 2156 expr = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL); 2157 if (!expr) 2158 return NULL; 2159 2160 if (!field->operands[0]) { 2161 expr_field_str(field, expr); 2162 return expr; 2163 } 2164 2165 if (field->operator == FIELD_OP_UNARY_MINUS) { 2166 char *subexpr; 2167 2168 strcat(expr, "-("); 2169 subexpr = expr_str(field->operands[0], ++level); 2170 if (!subexpr) { 2171 kfree(expr); 2172 return NULL; 2173 } 2174 strcat(expr, subexpr); 2175 strcat(expr, ")"); 2176 2177 kfree(subexpr); 2178 2179 return expr; 2180 } 2181 2182 expr_field_str(field->operands[0], expr); 2183 2184 switch (field->operator) { 2185 case FIELD_OP_MINUS: 2186 strcat(expr, "-"); 2187 break; 2188 case FIELD_OP_PLUS: 2189 strcat(expr, "+"); 2190 break; 2191 default: 2192 kfree(expr); 2193 return NULL; 2194 } 2195 2196 expr_field_str(field->operands[1], expr); 2197 2198 return expr; 2199 } 2200 2201 static int contains_operator(char *str) 2202 { 2203 enum field_op_id field_op = FIELD_OP_NONE; 2204 char *op; 2205 2206 op = strpbrk(str, "+-"); 2207 if (!op) 2208 return FIELD_OP_NONE; 2209 2210 switch (*op) { 2211 case '-': 2212 if (*str == '-') 2213 field_op = FIELD_OP_UNARY_MINUS; 2214 else 2215 field_op = FIELD_OP_MINUS; 2216 break; 2217 case '+': 2218 field_op = FIELD_OP_PLUS; 2219 break; 2220 default: 2221 break; 2222 } 2223 2224 return field_op; 2225 } 2226 2227 static void __destroy_hist_field(struct hist_field *hist_field) 2228 { 2229 kfree(hist_field->var.name); 2230 kfree(hist_field->name); 2231 kfree(hist_field->type); 2232 2233 kfree(hist_field); 2234 } 2235 2236 static void destroy_hist_field(struct hist_field *hist_field, 2237 unsigned int level) 2238 { 2239 unsigned int i; 2240 2241 if (level > 3) 2242 return; 2243 2244 if (!hist_field) 2245 return; 2246 2247 if (hist_field->flags & HIST_FIELD_FL_VAR_REF) 2248 return; /* var refs will be destroyed separately */ 2249 2250 for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++) 2251 destroy_hist_field(hist_field->operands[i], level + 1); 2252 2253 __destroy_hist_field(hist_field); 2254 } 2255 2256 static struct hist_field *create_hist_field(struct hist_trigger_data *hist_data, 2257 struct ftrace_event_field *field, 2258 unsigned long flags, 2259 char *var_name) 2260 { 2261 struct hist_field *hist_field; 2262 2263 if (field && is_function_field(field)) 2264 return NULL; 2265 2266 hist_field = kzalloc(sizeof(struct hist_field), GFP_KERNEL); 2267 if (!hist_field) 2268 return NULL; 2269 2270 hist_field->hist_data = hist_data; 2271 2272 if (flags & HIST_FIELD_FL_EXPR || flags & HIST_FIELD_FL_ALIAS) 2273 goto out; /* caller will populate */ 2274 2275 if (flags & HIST_FIELD_FL_VAR_REF) { 2276 hist_field->fn = hist_field_var_ref; 2277 goto out; 2278 } 2279 2280 if (flags & HIST_FIELD_FL_HITCOUNT) { 2281 hist_field->fn = hist_field_counter; 2282 hist_field->size = sizeof(u64); 2283 hist_field->type = kstrdup("u64", GFP_KERNEL); 2284 if (!hist_field->type) 2285 goto free; 2286 goto out; 2287 } 2288 2289 if (flags & HIST_FIELD_FL_STACKTRACE) { 2290 hist_field->fn = hist_field_none; 2291 goto out; 2292 } 2293 2294 if (flags & HIST_FIELD_FL_LOG2) { 2295 unsigned long fl = flags & ~HIST_FIELD_FL_LOG2; 2296 hist_field->fn = hist_field_log2; 2297 hist_field->operands[0] = create_hist_field(hist_data, field, fl, NULL); 2298 hist_field->size = hist_field->operands[0]->size; 2299 hist_field->type = kstrdup(hist_field->operands[0]->type, GFP_KERNEL); 2300 if (!hist_field->type) 2301 goto free; 2302 goto out; 2303 } 2304 2305 if (flags & HIST_FIELD_FL_TIMESTAMP) { 2306 hist_field->fn = hist_field_timestamp; 2307 hist_field->size = sizeof(u64); 2308 hist_field->type = kstrdup("u64", GFP_KERNEL); 2309 if (!hist_field->type) 2310 goto free; 2311 goto out; 2312 } 2313 2314 if (flags & HIST_FIELD_FL_CPU) { 2315 hist_field->fn = hist_field_cpu; 2316 hist_field->size = sizeof(int); 2317 hist_field->type = kstrdup("unsigned int", GFP_KERNEL); 2318 if (!hist_field->type) 2319 goto free; 2320 goto out; 2321 } 2322 2323 if (WARN_ON_ONCE(!field)) 2324 goto out; 2325 2326 if (is_string_field(field)) { 2327 flags |= HIST_FIELD_FL_STRING; 2328 2329 hist_field->size = MAX_FILTER_STR_VAL; 2330 hist_field->type = kstrdup(field->type, GFP_KERNEL); 2331 if (!hist_field->type) 2332 goto free; 2333 2334 if (field->filter_type == FILTER_STATIC_STRING) 2335 hist_field->fn = hist_field_string; 2336 else if (field->filter_type == FILTER_DYN_STRING) 2337 hist_field->fn = hist_field_dynstring; 2338 else 2339 hist_field->fn = hist_field_pstring; 2340 } else { 2341 hist_field->size = field->size; 2342 hist_field->is_signed = field->is_signed; 2343 hist_field->type = kstrdup(field->type, GFP_KERNEL); 2344 if (!hist_field->type) 2345 goto free; 2346 2347 hist_field->fn = select_value_fn(field->size, 2348 field->is_signed); 2349 if (!hist_field->fn) { 2350 destroy_hist_field(hist_field, 0); 2351 return NULL; 2352 } 2353 } 2354 out: 2355 hist_field->field = field; 2356 hist_field->flags = flags; 2357 2358 if (var_name) { 2359 hist_field->var.name = kstrdup(var_name, GFP_KERNEL); 2360 if (!hist_field->var.name) 2361 goto free; 2362 } 2363 2364 return hist_field; 2365 free: 2366 destroy_hist_field(hist_field, 0); 2367 return NULL; 2368 } 2369 2370 static void destroy_hist_fields(struct hist_trigger_data *hist_data) 2371 { 2372 unsigned int i; 2373 2374 for (i = 0; i < HIST_FIELDS_MAX; i++) { 2375 if (hist_data->fields[i]) { 2376 destroy_hist_field(hist_data->fields[i], 0); 2377 hist_data->fields[i] = NULL; 2378 } 2379 } 2380 2381 for (i = 0; i < hist_data->n_var_refs; i++) { 2382 WARN_ON(!(hist_data->var_refs[i]->flags & HIST_FIELD_FL_VAR_REF)); 2383 __destroy_hist_field(hist_data->var_refs[i]); 2384 hist_data->var_refs[i] = NULL; 2385 } 2386 } 2387 2388 static int init_var_ref(struct hist_field *ref_field, 2389 struct hist_field *var_field, 2390 char *system, char *event_name) 2391 { 2392 int err = 0; 2393 2394 ref_field->var.idx = var_field->var.idx; 2395 ref_field->var.hist_data = var_field->hist_data; 2396 ref_field->size = var_field->size; 2397 ref_field->is_signed = var_field->is_signed; 2398 ref_field->flags |= var_field->flags & 2399 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS); 2400 2401 if (system) { 2402 ref_field->system = kstrdup(system, GFP_KERNEL); 2403 if (!ref_field->system) 2404 return -ENOMEM; 2405 } 2406 2407 if (event_name) { 2408 ref_field->event_name = kstrdup(event_name, GFP_KERNEL); 2409 if (!ref_field->event_name) { 2410 err = -ENOMEM; 2411 goto free; 2412 } 2413 } 2414 2415 if (var_field->var.name) { 2416 ref_field->name = kstrdup(var_field->var.name, GFP_KERNEL); 2417 if (!ref_field->name) { 2418 err = -ENOMEM; 2419 goto free; 2420 } 2421 } else if (var_field->name) { 2422 ref_field->name = kstrdup(var_field->name, GFP_KERNEL); 2423 if (!ref_field->name) { 2424 err = -ENOMEM; 2425 goto free; 2426 } 2427 } 2428 2429 ref_field->type = kstrdup(var_field->type, GFP_KERNEL); 2430 if (!ref_field->type) { 2431 err = -ENOMEM; 2432 goto free; 2433 } 2434 out: 2435 return err; 2436 free: 2437 kfree(ref_field->system); 2438 kfree(ref_field->event_name); 2439 kfree(ref_field->name); 2440 2441 goto out; 2442 } 2443 2444 /** 2445 * create_var_ref - Create a variable reference and attach it to trigger 2446 * @hist_data: The trigger that will be referencing the variable 2447 * @var_field: The VAR field to create a reference to 2448 * @system: The optional system string 2449 * @event_name: The optional event_name string 2450 * 2451 * Given a variable hist_field, create a VAR_REF hist_field that 2452 * represents a reference to it. 2453 * 2454 * This function also adds the reference to the trigger that 2455 * now references the variable. 2456 * 2457 * Return: The VAR_REF field if successful, NULL if not 2458 */ 2459 static struct hist_field *create_var_ref(struct hist_trigger_data *hist_data, 2460 struct hist_field *var_field, 2461 char *system, char *event_name) 2462 { 2463 unsigned long flags = HIST_FIELD_FL_VAR_REF; 2464 struct hist_field *ref_field; 2465 2466 ref_field = create_hist_field(var_field->hist_data, NULL, flags, NULL); 2467 if (ref_field) { 2468 if (init_var_ref(ref_field, var_field, system, event_name)) { 2469 destroy_hist_field(ref_field, 0); 2470 return NULL; 2471 } 2472 2473 hist_data->var_refs[hist_data->n_var_refs] = ref_field; 2474 ref_field->var_ref_idx = hist_data->n_var_refs++; 2475 } 2476 2477 return ref_field; 2478 } 2479 2480 static bool is_var_ref(char *var_name) 2481 { 2482 if (!var_name || strlen(var_name) < 2 || var_name[0] != '$') 2483 return false; 2484 2485 return true; 2486 } 2487 2488 static char *field_name_from_var(struct hist_trigger_data *hist_data, 2489 char *var_name) 2490 { 2491 char *name, *field; 2492 unsigned int i; 2493 2494 for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) { 2495 name = hist_data->attrs->var_defs.name[i]; 2496 2497 if (strcmp(var_name, name) == 0) { 2498 field = hist_data->attrs->var_defs.expr[i]; 2499 if (contains_operator(field) || is_var_ref(field)) 2500 continue; 2501 return field; 2502 } 2503 } 2504 2505 return NULL; 2506 } 2507 2508 static char *local_field_var_ref(struct hist_trigger_data *hist_data, 2509 char *system, char *event_name, 2510 char *var_name) 2511 { 2512 struct trace_event_call *call; 2513 2514 if (system && event_name) { 2515 call = hist_data->event_file->event_call; 2516 2517 if (strcmp(system, call->class->system) != 0) 2518 return NULL; 2519 2520 if (strcmp(event_name, trace_event_name(call)) != 0) 2521 return NULL; 2522 } 2523 2524 if (!!system != !!event_name) 2525 return NULL; 2526 2527 if (!is_var_ref(var_name)) 2528 return NULL; 2529 2530 var_name++; 2531 2532 return field_name_from_var(hist_data, var_name); 2533 } 2534 2535 static struct hist_field *parse_var_ref(struct hist_trigger_data *hist_data, 2536 char *system, char *event_name, 2537 char *var_name) 2538 { 2539 struct hist_field *var_field = NULL, *ref_field = NULL; 2540 2541 if (!is_var_ref(var_name)) 2542 return NULL; 2543 2544 var_name++; 2545 2546 var_field = find_event_var(hist_data, system, event_name, var_name); 2547 if (var_field) 2548 ref_field = create_var_ref(hist_data, var_field, 2549 system, event_name); 2550 2551 if (!ref_field) 2552 hist_err_event("Couldn't find variable: $", 2553 system, event_name, var_name); 2554 2555 return ref_field; 2556 } 2557 2558 static struct ftrace_event_field * 2559 parse_field(struct hist_trigger_data *hist_data, struct trace_event_file *file, 2560 char *field_str, unsigned long *flags) 2561 { 2562 struct ftrace_event_field *field = NULL; 2563 char *field_name, *modifier, *str; 2564 2565 modifier = str = kstrdup(field_str, GFP_KERNEL); 2566 if (!modifier) 2567 return ERR_PTR(-ENOMEM); 2568 2569 field_name = strsep(&modifier, "."); 2570 if (modifier) { 2571 if (strcmp(modifier, "hex") == 0) 2572 *flags |= HIST_FIELD_FL_HEX; 2573 else if (strcmp(modifier, "sym") == 0) 2574 *flags |= HIST_FIELD_FL_SYM; 2575 else if (strcmp(modifier, "sym-offset") == 0) 2576 *flags |= HIST_FIELD_FL_SYM_OFFSET; 2577 else if ((strcmp(modifier, "execname") == 0) && 2578 (strcmp(field_name, "common_pid") == 0)) 2579 *flags |= HIST_FIELD_FL_EXECNAME; 2580 else if (strcmp(modifier, "syscall") == 0) 2581 *flags |= HIST_FIELD_FL_SYSCALL; 2582 else if (strcmp(modifier, "log2") == 0) 2583 *flags |= HIST_FIELD_FL_LOG2; 2584 else if (strcmp(modifier, "usecs") == 0) 2585 *flags |= HIST_FIELD_FL_TIMESTAMP_USECS; 2586 else { 2587 hist_err("Invalid field modifier: ", modifier); 2588 field = ERR_PTR(-EINVAL); 2589 goto out; 2590 } 2591 } 2592 2593 if (strcmp(field_name, "common_timestamp") == 0) { 2594 *flags |= HIST_FIELD_FL_TIMESTAMP; 2595 hist_data->enable_timestamps = true; 2596 if (*flags & HIST_FIELD_FL_TIMESTAMP_USECS) 2597 hist_data->attrs->ts_in_usecs = true; 2598 } else if (strcmp(field_name, "cpu") == 0) 2599 *flags |= HIST_FIELD_FL_CPU; 2600 else { 2601 field = trace_find_event_field(file->event_call, field_name); 2602 if (!field || !field->size) { 2603 hist_err("Couldn't find field: ", field_name); 2604 field = ERR_PTR(-EINVAL); 2605 goto out; 2606 } 2607 } 2608 out: 2609 kfree(str); 2610 2611 return field; 2612 } 2613 2614 static struct hist_field *create_alias(struct hist_trigger_data *hist_data, 2615 struct hist_field *var_ref, 2616 char *var_name) 2617 { 2618 struct hist_field *alias = NULL; 2619 unsigned long flags = HIST_FIELD_FL_ALIAS | HIST_FIELD_FL_VAR; 2620 2621 alias = create_hist_field(hist_data, NULL, flags, var_name); 2622 if (!alias) 2623 return NULL; 2624 2625 alias->fn = var_ref->fn; 2626 alias->operands[0] = var_ref; 2627 2628 if (init_var_ref(alias, var_ref, var_ref->system, var_ref->event_name)) { 2629 destroy_hist_field(alias, 0); 2630 return NULL; 2631 } 2632 2633 return alias; 2634 } 2635 2636 static struct hist_field *parse_atom(struct hist_trigger_data *hist_data, 2637 struct trace_event_file *file, char *str, 2638 unsigned long *flags, char *var_name) 2639 { 2640 char *s, *ref_system = NULL, *ref_event = NULL, *ref_var = str; 2641 struct ftrace_event_field *field = NULL; 2642 struct hist_field *hist_field = NULL; 2643 int ret = 0; 2644 2645 s = strchr(str, '.'); 2646 if (s) { 2647 s = strchr(++s, '.'); 2648 if (s) { 2649 ref_system = strsep(&str, "."); 2650 if (!str) { 2651 ret = -EINVAL; 2652 goto out; 2653 } 2654 ref_event = strsep(&str, "."); 2655 if (!str) { 2656 ret = -EINVAL; 2657 goto out; 2658 } 2659 ref_var = str; 2660 } 2661 } 2662 2663 s = local_field_var_ref(hist_data, ref_system, ref_event, ref_var); 2664 if (!s) { 2665 hist_field = parse_var_ref(hist_data, ref_system, ref_event, ref_var); 2666 if (hist_field) { 2667 if (var_name) { 2668 hist_field = create_alias(hist_data, hist_field, var_name); 2669 if (!hist_field) { 2670 ret = -ENOMEM; 2671 goto out; 2672 } 2673 } 2674 return hist_field; 2675 } 2676 } else 2677 str = s; 2678 2679 field = parse_field(hist_data, file, str, flags); 2680 if (IS_ERR(field)) { 2681 ret = PTR_ERR(field); 2682 goto out; 2683 } 2684 2685 hist_field = create_hist_field(hist_data, field, *flags, var_name); 2686 if (!hist_field) { 2687 ret = -ENOMEM; 2688 goto out; 2689 } 2690 2691 return hist_field; 2692 out: 2693 return ERR_PTR(ret); 2694 } 2695 2696 static struct hist_field *parse_expr(struct hist_trigger_data *hist_data, 2697 struct trace_event_file *file, 2698 char *str, unsigned long flags, 2699 char *var_name, unsigned int level); 2700 2701 static struct hist_field *parse_unary(struct hist_trigger_data *hist_data, 2702 struct trace_event_file *file, 2703 char *str, unsigned long flags, 2704 char *var_name, unsigned int level) 2705 { 2706 struct hist_field *operand1, *expr = NULL; 2707 unsigned long operand_flags; 2708 int ret = 0; 2709 char *s; 2710 2711 /* we support only -(xxx) i.e. explicit parens required */ 2712 2713 if (level > 3) { 2714 hist_err("Too many subexpressions (3 max): ", str); 2715 ret = -EINVAL; 2716 goto free; 2717 } 2718 2719 str++; /* skip leading '-' */ 2720 2721 s = strchr(str, '('); 2722 if (s) 2723 str++; 2724 else { 2725 ret = -EINVAL; 2726 goto free; 2727 } 2728 2729 s = strrchr(str, ')'); 2730 if (s) 2731 *s = '\0'; 2732 else { 2733 ret = -EINVAL; /* no closing ')' */ 2734 goto free; 2735 } 2736 2737 flags |= HIST_FIELD_FL_EXPR; 2738 expr = create_hist_field(hist_data, NULL, flags, var_name); 2739 if (!expr) { 2740 ret = -ENOMEM; 2741 goto free; 2742 } 2743 2744 operand_flags = 0; 2745 operand1 = parse_expr(hist_data, file, str, operand_flags, NULL, ++level); 2746 if (IS_ERR(operand1)) { 2747 ret = PTR_ERR(operand1); 2748 goto free; 2749 } 2750 2751 expr->flags |= operand1->flags & 2752 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS); 2753 expr->fn = hist_field_unary_minus; 2754 expr->operands[0] = operand1; 2755 expr->operator = FIELD_OP_UNARY_MINUS; 2756 expr->name = expr_str(expr, 0); 2757 expr->type = kstrdup(operand1->type, GFP_KERNEL); 2758 if (!expr->type) { 2759 ret = -ENOMEM; 2760 goto free; 2761 } 2762 2763 return expr; 2764 free: 2765 destroy_hist_field(expr, 0); 2766 return ERR_PTR(ret); 2767 } 2768 2769 static int check_expr_operands(struct hist_field *operand1, 2770 struct hist_field *operand2) 2771 { 2772 unsigned long operand1_flags = operand1->flags; 2773 unsigned long operand2_flags = operand2->flags; 2774 2775 if ((operand1_flags & HIST_FIELD_FL_VAR_REF) || 2776 (operand1_flags & HIST_FIELD_FL_ALIAS)) { 2777 struct hist_field *var; 2778 2779 var = find_var_field(operand1->var.hist_data, operand1->name); 2780 if (!var) 2781 return -EINVAL; 2782 operand1_flags = var->flags; 2783 } 2784 2785 if ((operand2_flags & HIST_FIELD_FL_VAR_REF) || 2786 (operand2_flags & HIST_FIELD_FL_ALIAS)) { 2787 struct hist_field *var; 2788 2789 var = find_var_field(operand2->var.hist_data, operand2->name); 2790 if (!var) 2791 return -EINVAL; 2792 operand2_flags = var->flags; 2793 } 2794 2795 if ((operand1_flags & HIST_FIELD_FL_TIMESTAMP_USECS) != 2796 (operand2_flags & HIST_FIELD_FL_TIMESTAMP_USECS)) { 2797 hist_err("Timestamp units in expression don't match", NULL); 2798 return -EINVAL; 2799 } 2800 2801 return 0; 2802 } 2803 2804 static struct hist_field *parse_expr(struct hist_trigger_data *hist_data, 2805 struct trace_event_file *file, 2806 char *str, unsigned long flags, 2807 char *var_name, unsigned int level) 2808 { 2809 struct hist_field *operand1 = NULL, *operand2 = NULL, *expr = NULL; 2810 unsigned long operand_flags; 2811 int field_op, ret = -EINVAL; 2812 char *sep, *operand1_str; 2813 2814 if (level > 3) { 2815 hist_err("Too many subexpressions (3 max): ", str); 2816 return ERR_PTR(-EINVAL); 2817 } 2818 2819 field_op = contains_operator(str); 2820 2821 if (field_op == FIELD_OP_NONE) 2822 return parse_atom(hist_data, file, str, &flags, var_name); 2823 2824 if (field_op == FIELD_OP_UNARY_MINUS) 2825 return parse_unary(hist_data, file, str, flags, var_name, ++level); 2826 2827 switch (field_op) { 2828 case FIELD_OP_MINUS: 2829 sep = "-"; 2830 break; 2831 case FIELD_OP_PLUS: 2832 sep = "+"; 2833 break; 2834 default: 2835 goto free; 2836 } 2837 2838 operand1_str = strsep(&str, sep); 2839 if (!operand1_str || !str) 2840 goto free; 2841 2842 operand_flags = 0; 2843 operand1 = parse_atom(hist_data, file, operand1_str, 2844 &operand_flags, NULL); 2845 if (IS_ERR(operand1)) { 2846 ret = PTR_ERR(operand1); 2847 operand1 = NULL; 2848 goto free; 2849 } 2850 2851 /* rest of string could be another expression e.g. b+c in a+b+c */ 2852 operand_flags = 0; 2853 operand2 = parse_expr(hist_data, file, str, operand_flags, NULL, ++level); 2854 if (IS_ERR(operand2)) { 2855 ret = PTR_ERR(operand2); 2856 operand2 = NULL; 2857 goto free; 2858 } 2859 2860 ret = check_expr_operands(operand1, operand2); 2861 if (ret) 2862 goto free; 2863 2864 flags |= HIST_FIELD_FL_EXPR; 2865 2866 flags |= operand1->flags & 2867 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS); 2868 2869 expr = create_hist_field(hist_data, NULL, flags, var_name); 2870 if (!expr) { 2871 ret = -ENOMEM; 2872 goto free; 2873 } 2874 2875 operand1->read_once = true; 2876 operand2->read_once = true; 2877 2878 expr->operands[0] = operand1; 2879 expr->operands[1] = operand2; 2880 expr->operator = field_op; 2881 expr->name = expr_str(expr, 0); 2882 expr->type = kstrdup(operand1->type, GFP_KERNEL); 2883 if (!expr->type) { 2884 ret = -ENOMEM; 2885 goto free; 2886 } 2887 2888 switch (field_op) { 2889 case FIELD_OP_MINUS: 2890 expr->fn = hist_field_minus; 2891 break; 2892 case FIELD_OP_PLUS: 2893 expr->fn = hist_field_plus; 2894 break; 2895 default: 2896 ret = -EINVAL; 2897 goto free; 2898 } 2899 2900 return expr; 2901 free: 2902 destroy_hist_field(operand1, 0); 2903 destroy_hist_field(operand2, 0); 2904 destroy_hist_field(expr, 0); 2905 2906 return ERR_PTR(ret); 2907 } 2908 2909 static char *find_trigger_filter(struct hist_trigger_data *hist_data, 2910 struct trace_event_file *file) 2911 { 2912 struct event_trigger_data *test; 2913 2914 list_for_each_entry_rcu(test, &file->triggers, list) { 2915 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 2916 if (test->private_data == hist_data) 2917 return test->filter_str; 2918 } 2919 } 2920 2921 return NULL; 2922 } 2923 2924 static struct event_command trigger_hist_cmd; 2925 static int event_hist_trigger_func(struct event_command *cmd_ops, 2926 struct trace_event_file *file, 2927 char *glob, char *cmd, char *param); 2928 2929 static bool compatible_keys(struct hist_trigger_data *target_hist_data, 2930 struct hist_trigger_data *hist_data, 2931 unsigned int n_keys) 2932 { 2933 struct hist_field *target_hist_field, *hist_field; 2934 unsigned int n, i, j; 2935 2936 if (hist_data->n_fields - hist_data->n_vals != n_keys) 2937 return false; 2938 2939 i = hist_data->n_vals; 2940 j = target_hist_data->n_vals; 2941 2942 for (n = 0; n < n_keys; n++) { 2943 hist_field = hist_data->fields[i + n]; 2944 target_hist_field = target_hist_data->fields[j + n]; 2945 2946 if (strcmp(hist_field->type, target_hist_field->type) != 0) 2947 return false; 2948 if (hist_field->size != target_hist_field->size) 2949 return false; 2950 if (hist_field->is_signed != target_hist_field->is_signed) 2951 return false; 2952 } 2953 2954 return true; 2955 } 2956 2957 static struct hist_trigger_data * 2958 find_compatible_hist(struct hist_trigger_data *target_hist_data, 2959 struct trace_event_file *file) 2960 { 2961 struct hist_trigger_data *hist_data; 2962 struct event_trigger_data *test; 2963 unsigned int n_keys; 2964 2965 n_keys = target_hist_data->n_fields - target_hist_data->n_vals; 2966 2967 list_for_each_entry_rcu(test, &file->triggers, list) { 2968 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 2969 hist_data = test->private_data; 2970 2971 if (compatible_keys(target_hist_data, hist_data, n_keys)) 2972 return hist_data; 2973 } 2974 } 2975 2976 return NULL; 2977 } 2978 2979 static struct trace_event_file *event_file(struct trace_array *tr, 2980 char *system, char *event_name) 2981 { 2982 struct trace_event_file *file; 2983 2984 file = __find_event_file(tr, system, event_name); 2985 if (!file) 2986 return ERR_PTR(-EINVAL); 2987 2988 return file; 2989 } 2990 2991 static struct hist_field * 2992 find_synthetic_field_var(struct hist_trigger_data *target_hist_data, 2993 char *system, char *event_name, char *field_name) 2994 { 2995 struct hist_field *event_var; 2996 char *synthetic_name; 2997 2998 synthetic_name = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL); 2999 if (!synthetic_name) 3000 return ERR_PTR(-ENOMEM); 3001 3002 strcpy(synthetic_name, "synthetic_"); 3003 strcat(synthetic_name, field_name); 3004 3005 event_var = find_event_var(target_hist_data, system, event_name, synthetic_name); 3006 3007 kfree(synthetic_name); 3008 3009 return event_var; 3010 } 3011 3012 /** 3013 * create_field_var_hist - Automatically create a histogram and var for a field 3014 * @target_hist_data: The target hist trigger 3015 * @subsys_name: Optional subsystem name 3016 * @event_name: Optional event name 3017 * @field_name: The name of the field (and the resulting variable) 3018 * 3019 * Hist trigger actions fetch data from variables, not directly from 3020 * events. However, for convenience, users are allowed to directly 3021 * specify an event field in an action, which will be automatically 3022 * converted into a variable on their behalf. 3023 3024 * If a user specifies a field on an event that isn't the event the 3025 * histogram currently being defined (the target event histogram), the 3026 * only way that can be accomplished is if a new hist trigger is 3027 * created and the field variable defined on that. 3028 * 3029 * This function creates a new histogram compatible with the target 3030 * event (meaning a histogram with the same key as the target 3031 * histogram), and creates a variable for the specified field, but 3032 * with 'synthetic_' prepended to the variable name in order to avoid 3033 * collision with normal field variables. 3034 * 3035 * Return: The variable created for the field. 3036 */ 3037 static struct hist_field * 3038 create_field_var_hist(struct hist_trigger_data *target_hist_data, 3039 char *subsys_name, char *event_name, char *field_name) 3040 { 3041 struct trace_array *tr = target_hist_data->event_file->tr; 3042 struct hist_field *event_var = ERR_PTR(-EINVAL); 3043 struct hist_trigger_data *hist_data; 3044 unsigned int i, n, first = true; 3045 struct field_var_hist *var_hist; 3046 struct trace_event_file *file; 3047 struct hist_field *key_field; 3048 char *saved_filter; 3049 char *cmd; 3050 int ret; 3051 3052 if (target_hist_data->n_field_var_hists >= SYNTH_FIELDS_MAX) { 3053 hist_err_event("onmatch: Too many field variables defined: ", 3054 subsys_name, event_name, field_name); 3055 return ERR_PTR(-EINVAL); 3056 } 3057 3058 file = event_file(tr, subsys_name, event_name); 3059 3060 if (IS_ERR(file)) { 3061 hist_err_event("onmatch: Event file not found: ", 3062 subsys_name, event_name, field_name); 3063 ret = PTR_ERR(file); 3064 return ERR_PTR(ret); 3065 } 3066 3067 /* 3068 * Look for a histogram compatible with target. We'll use the 3069 * found histogram specification to create a new matching 3070 * histogram with our variable on it. target_hist_data is not 3071 * yet a registered histogram so we can't use that. 3072 */ 3073 hist_data = find_compatible_hist(target_hist_data, file); 3074 if (!hist_data) { 3075 hist_err_event("onmatch: Matching event histogram not found: ", 3076 subsys_name, event_name, field_name); 3077 return ERR_PTR(-EINVAL); 3078 } 3079 3080 /* See if a synthetic field variable has already been created */ 3081 event_var = find_synthetic_field_var(target_hist_data, subsys_name, 3082 event_name, field_name); 3083 if (!IS_ERR_OR_NULL(event_var)) 3084 return event_var; 3085 3086 var_hist = kzalloc(sizeof(*var_hist), GFP_KERNEL); 3087 if (!var_hist) 3088 return ERR_PTR(-ENOMEM); 3089 3090 cmd = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL); 3091 if (!cmd) { 3092 kfree(var_hist); 3093 return ERR_PTR(-ENOMEM); 3094 } 3095 3096 /* Use the same keys as the compatible histogram */ 3097 strcat(cmd, "keys="); 3098 3099 for_each_hist_key_field(i, hist_data) { 3100 key_field = hist_data->fields[i]; 3101 if (!first) 3102 strcat(cmd, ","); 3103 strcat(cmd, key_field->field->name); 3104 first = false; 3105 } 3106 3107 /* Create the synthetic field variable specification */ 3108 strcat(cmd, ":synthetic_"); 3109 strcat(cmd, field_name); 3110 strcat(cmd, "="); 3111 strcat(cmd, field_name); 3112 3113 /* Use the same filter as the compatible histogram */ 3114 saved_filter = find_trigger_filter(hist_data, file); 3115 if (saved_filter) { 3116 strcat(cmd, " if "); 3117 strcat(cmd, saved_filter); 3118 } 3119 3120 var_hist->cmd = kstrdup(cmd, GFP_KERNEL); 3121 if (!var_hist->cmd) { 3122 kfree(cmd); 3123 kfree(var_hist); 3124 return ERR_PTR(-ENOMEM); 3125 } 3126 3127 /* Save the compatible histogram information */ 3128 var_hist->hist_data = hist_data; 3129 3130 /* Create the new histogram with our variable */ 3131 ret = event_hist_trigger_func(&trigger_hist_cmd, file, 3132 "", "hist", cmd); 3133 if (ret) { 3134 kfree(cmd); 3135 kfree(var_hist->cmd); 3136 kfree(var_hist); 3137 hist_err_event("onmatch: Couldn't create histogram for field: ", 3138 subsys_name, event_name, field_name); 3139 return ERR_PTR(ret); 3140 } 3141 3142 kfree(cmd); 3143 3144 /* If we can't find the variable, something went wrong */ 3145 event_var = find_synthetic_field_var(target_hist_data, subsys_name, 3146 event_name, field_name); 3147 if (IS_ERR_OR_NULL(event_var)) { 3148 kfree(var_hist->cmd); 3149 kfree(var_hist); 3150 hist_err_event("onmatch: Couldn't find synthetic variable: ", 3151 subsys_name, event_name, field_name); 3152 return ERR_PTR(-EINVAL); 3153 } 3154 3155 n = target_hist_data->n_field_var_hists; 3156 target_hist_data->field_var_hists[n] = var_hist; 3157 target_hist_data->n_field_var_hists++; 3158 3159 return event_var; 3160 } 3161 3162 static struct hist_field * 3163 find_target_event_var(struct hist_trigger_data *hist_data, 3164 char *subsys_name, char *event_name, char *var_name) 3165 { 3166 struct trace_event_file *file = hist_data->event_file; 3167 struct hist_field *hist_field = NULL; 3168 3169 if (subsys_name) { 3170 struct trace_event_call *call; 3171 3172 if (!event_name) 3173 return NULL; 3174 3175 call = file->event_call; 3176 3177 if (strcmp(subsys_name, call->class->system) != 0) 3178 return NULL; 3179 3180 if (strcmp(event_name, trace_event_name(call)) != 0) 3181 return NULL; 3182 } 3183 3184 hist_field = find_var_field(hist_data, var_name); 3185 3186 return hist_field; 3187 } 3188 3189 static inline void __update_field_vars(struct tracing_map_elt *elt, 3190 struct ring_buffer_event *rbe, 3191 void *rec, 3192 struct field_var **field_vars, 3193 unsigned int n_field_vars, 3194 unsigned int field_var_str_start) 3195 { 3196 struct hist_elt_data *elt_data = elt->private_data; 3197 unsigned int i, j, var_idx; 3198 u64 var_val; 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 = val->fn(val, elt, rbe, rec); 3206 var_idx = var->var.idx; 3207 3208 if (val->flags & HIST_FIELD_FL_STRING) { 3209 char *str = elt_data->field_var_str[j++]; 3210 char *val_str = (char *)(uintptr_t)var_val; 3211 3212 strscpy(str, val_str, STR_VAR_LEN_MAX); 3213 var_val = (u64)(uintptr_t)str; 3214 } 3215 tracing_map_set_var(elt, var_idx, var_val); 3216 } 3217 } 3218 3219 static void update_field_vars(struct hist_trigger_data *hist_data, 3220 struct tracing_map_elt *elt, 3221 struct ring_buffer_event *rbe, 3222 void *rec) 3223 { 3224 __update_field_vars(elt, rbe, rec, hist_data->field_vars, 3225 hist_data->n_field_vars, 0); 3226 } 3227 3228 static void update_max_vars(struct hist_trigger_data *hist_data, 3229 struct tracing_map_elt *elt, 3230 struct ring_buffer_event *rbe, 3231 void *rec) 3232 { 3233 __update_field_vars(elt, rbe, rec, hist_data->max_vars, 3234 hist_data->n_max_vars, hist_data->n_field_var_str); 3235 } 3236 3237 static struct hist_field *create_var(struct hist_trigger_data *hist_data, 3238 struct trace_event_file *file, 3239 char *name, int size, const char *type) 3240 { 3241 struct hist_field *var; 3242 int idx; 3243 3244 if (find_var(hist_data, file, name) && !hist_data->remove) { 3245 var = ERR_PTR(-EINVAL); 3246 goto out; 3247 } 3248 3249 var = kzalloc(sizeof(struct hist_field), GFP_KERNEL); 3250 if (!var) { 3251 var = ERR_PTR(-ENOMEM); 3252 goto out; 3253 } 3254 3255 idx = tracing_map_add_var(hist_data->map); 3256 if (idx < 0) { 3257 kfree(var); 3258 var = ERR_PTR(-EINVAL); 3259 goto out; 3260 } 3261 3262 var->flags = HIST_FIELD_FL_VAR; 3263 var->var.idx = idx; 3264 var->var.hist_data = var->hist_data = hist_data; 3265 var->size = size; 3266 var->var.name = kstrdup(name, GFP_KERNEL); 3267 var->type = kstrdup(type, GFP_KERNEL); 3268 if (!var->var.name || !var->type) { 3269 kfree(var->var.name); 3270 kfree(var->type); 3271 kfree(var); 3272 var = ERR_PTR(-ENOMEM); 3273 } 3274 out: 3275 return var; 3276 } 3277 3278 static struct field_var *create_field_var(struct hist_trigger_data *hist_data, 3279 struct trace_event_file *file, 3280 char *field_name) 3281 { 3282 struct hist_field *val = NULL, *var = NULL; 3283 unsigned long flags = HIST_FIELD_FL_VAR; 3284 struct field_var *field_var; 3285 int ret = 0; 3286 3287 if (hist_data->n_field_vars >= SYNTH_FIELDS_MAX) { 3288 hist_err("Too many field variables defined: ", field_name); 3289 ret = -EINVAL; 3290 goto err; 3291 } 3292 3293 val = parse_atom(hist_data, file, field_name, &flags, NULL); 3294 if (IS_ERR(val)) { 3295 hist_err("Couldn't parse field variable: ", field_name); 3296 ret = PTR_ERR(val); 3297 goto err; 3298 } 3299 3300 var = create_var(hist_data, file, field_name, val->size, val->type); 3301 if (IS_ERR(var)) { 3302 hist_err("Couldn't create or find variable: ", field_name); 3303 kfree(val); 3304 ret = PTR_ERR(var); 3305 goto err; 3306 } 3307 3308 field_var = kzalloc(sizeof(struct field_var), GFP_KERNEL); 3309 if (!field_var) { 3310 kfree(val); 3311 kfree(var); 3312 ret = -ENOMEM; 3313 goto err; 3314 } 3315 3316 field_var->var = var; 3317 field_var->val = val; 3318 out: 3319 return field_var; 3320 err: 3321 field_var = ERR_PTR(ret); 3322 goto out; 3323 } 3324 3325 /** 3326 * create_target_field_var - Automatically create a variable for a field 3327 * @target_hist_data: The target hist trigger 3328 * @subsys_name: Optional subsystem name 3329 * @event_name: Optional event name 3330 * @var_name: The name of the field (and the resulting variable) 3331 * 3332 * Hist trigger actions fetch data from variables, not directly from 3333 * events. However, for convenience, users are allowed to directly 3334 * specify an event field in an action, which will be automatically 3335 * converted into a variable on their behalf. 3336 3337 * This function creates a field variable with the name var_name on 3338 * the hist trigger currently being defined on the target event. If 3339 * subsys_name and event_name are specified, this function simply 3340 * verifies that they do in fact match the target event subsystem and 3341 * event name. 3342 * 3343 * Return: The variable created for the field. 3344 */ 3345 static struct field_var * 3346 create_target_field_var(struct hist_trigger_data *target_hist_data, 3347 char *subsys_name, char *event_name, char *var_name) 3348 { 3349 struct trace_event_file *file = target_hist_data->event_file; 3350 3351 if (subsys_name) { 3352 struct trace_event_call *call; 3353 3354 if (!event_name) 3355 return NULL; 3356 3357 call = file->event_call; 3358 3359 if (strcmp(subsys_name, call->class->system) != 0) 3360 return NULL; 3361 3362 if (strcmp(event_name, trace_event_name(call)) != 0) 3363 return NULL; 3364 } 3365 3366 return create_field_var(target_hist_data, file, var_name); 3367 } 3368 3369 static void onmax_print(struct seq_file *m, 3370 struct hist_trigger_data *hist_data, 3371 struct tracing_map_elt *elt, 3372 struct action_data *data) 3373 { 3374 unsigned int i, save_var_idx, max_idx = data->onmax.max_var->var.idx; 3375 3376 seq_printf(m, "\n\tmax: %10llu", tracing_map_read_var(elt, max_idx)); 3377 3378 for (i = 0; i < hist_data->n_max_vars; i++) { 3379 struct hist_field *save_val = hist_data->max_vars[i]->val; 3380 struct hist_field *save_var = hist_data->max_vars[i]->var; 3381 u64 val; 3382 3383 save_var_idx = save_var->var.idx; 3384 3385 val = tracing_map_read_var(elt, save_var_idx); 3386 3387 if (save_val->flags & HIST_FIELD_FL_STRING) { 3388 seq_printf(m, " %s: %-32s", save_var->var.name, 3389 (char *)(uintptr_t)(val)); 3390 } else 3391 seq_printf(m, " %s: %10llu", save_var->var.name, val); 3392 } 3393 } 3394 3395 static void onmax_save(struct hist_trigger_data *hist_data, 3396 struct tracing_map_elt *elt, void *rec, 3397 struct ring_buffer_event *rbe, 3398 struct action_data *data, u64 *var_ref_vals) 3399 { 3400 unsigned int max_idx = data->onmax.max_var->var.idx; 3401 unsigned int max_var_ref_idx = data->onmax.max_var_ref_idx; 3402 3403 u64 var_val, max_val; 3404 3405 var_val = var_ref_vals[max_var_ref_idx]; 3406 max_val = tracing_map_read_var(elt, max_idx); 3407 3408 if (var_val <= max_val) 3409 return; 3410 3411 tracing_map_set_var(elt, max_idx, var_val); 3412 3413 update_max_vars(hist_data, elt, rbe, rec); 3414 } 3415 3416 static void onmax_destroy(struct action_data *data) 3417 { 3418 unsigned int i; 3419 3420 destroy_hist_field(data->onmax.max_var, 0); 3421 destroy_hist_field(data->onmax.var, 0); 3422 3423 kfree(data->onmax.var_str); 3424 kfree(data->onmax.fn_name); 3425 3426 for (i = 0; i < data->n_params; i++) 3427 kfree(data->params[i]); 3428 3429 kfree(data); 3430 } 3431 3432 static int onmax_create(struct hist_trigger_data *hist_data, 3433 struct action_data *data) 3434 { 3435 struct trace_event_file *file = hist_data->event_file; 3436 struct hist_field *var_field, *ref_field, *max_var; 3437 unsigned int var_ref_idx = hist_data->n_var_refs; 3438 struct field_var *field_var; 3439 char *onmax_var_str, *param; 3440 unsigned int i; 3441 int ret = 0; 3442 3443 onmax_var_str = data->onmax.var_str; 3444 if (onmax_var_str[0] != '$') { 3445 hist_err("onmax: For onmax(x), x must be a variable: ", onmax_var_str); 3446 return -EINVAL; 3447 } 3448 onmax_var_str++; 3449 3450 var_field = find_target_event_var(hist_data, NULL, NULL, onmax_var_str); 3451 if (!var_field) { 3452 hist_err("onmax: Couldn't find onmax variable: ", onmax_var_str); 3453 return -EINVAL; 3454 } 3455 3456 ref_field = create_var_ref(hist_data, var_field, NULL, NULL); 3457 if (!ref_field) 3458 return -ENOMEM; 3459 3460 data->onmax.var = ref_field; 3461 3462 data->fn = onmax_save; 3463 data->onmax.max_var_ref_idx = var_ref_idx; 3464 max_var = create_var(hist_data, file, "max", sizeof(u64), "u64"); 3465 if (IS_ERR(max_var)) { 3466 hist_err("onmax: Couldn't create onmax variable: ", "max"); 3467 ret = PTR_ERR(max_var); 3468 goto out; 3469 } 3470 data->onmax.max_var = max_var; 3471 3472 for (i = 0; i < data->n_params; i++) { 3473 param = kstrdup(data->params[i], GFP_KERNEL); 3474 if (!param) { 3475 ret = -ENOMEM; 3476 goto out; 3477 } 3478 3479 field_var = create_target_field_var(hist_data, NULL, NULL, param); 3480 if (IS_ERR(field_var)) { 3481 hist_err("onmax: Couldn't create field variable: ", param); 3482 ret = PTR_ERR(field_var); 3483 kfree(param); 3484 goto out; 3485 } 3486 3487 hist_data->max_vars[hist_data->n_max_vars++] = field_var; 3488 if (field_var->val->flags & HIST_FIELD_FL_STRING) 3489 hist_data->n_max_var_str++; 3490 3491 kfree(param); 3492 } 3493 out: 3494 return ret; 3495 } 3496 3497 static int parse_action_params(char *params, struct action_data *data) 3498 { 3499 char *param, *saved_param; 3500 int ret = 0; 3501 3502 while (params) { 3503 if (data->n_params >= SYNTH_FIELDS_MAX) 3504 goto out; 3505 3506 param = strsep(¶ms, ","); 3507 if (!param) { 3508 ret = -EINVAL; 3509 goto out; 3510 } 3511 3512 param = strstrip(param); 3513 if (strlen(param) < 2) { 3514 hist_err("Invalid action param: ", param); 3515 ret = -EINVAL; 3516 goto out; 3517 } 3518 3519 saved_param = kstrdup(param, GFP_KERNEL); 3520 if (!saved_param) { 3521 ret = -ENOMEM; 3522 goto out; 3523 } 3524 3525 data->params[data->n_params++] = saved_param; 3526 } 3527 out: 3528 return ret; 3529 } 3530 3531 static struct action_data *onmax_parse(char *str) 3532 { 3533 char *onmax_fn_name, *onmax_var_str; 3534 struct action_data *data; 3535 int ret = -EINVAL; 3536 3537 data = kzalloc(sizeof(*data), GFP_KERNEL); 3538 if (!data) 3539 return ERR_PTR(-ENOMEM); 3540 3541 onmax_var_str = strsep(&str, ")"); 3542 if (!onmax_var_str || !str) { 3543 ret = -EINVAL; 3544 goto free; 3545 } 3546 3547 data->onmax.var_str = kstrdup(onmax_var_str, GFP_KERNEL); 3548 if (!data->onmax.var_str) { 3549 ret = -ENOMEM; 3550 goto free; 3551 } 3552 3553 strsep(&str, "."); 3554 if (!str) 3555 goto free; 3556 3557 onmax_fn_name = strsep(&str, "("); 3558 if (!onmax_fn_name || !str) 3559 goto free; 3560 3561 if (str_has_prefix(onmax_fn_name, "save")) { 3562 char *params = strsep(&str, ")"); 3563 3564 if (!params) { 3565 ret = -EINVAL; 3566 goto free; 3567 } 3568 3569 ret = parse_action_params(params, data); 3570 if (ret) 3571 goto free; 3572 } else 3573 goto free; 3574 3575 data->onmax.fn_name = kstrdup(onmax_fn_name, GFP_KERNEL); 3576 if (!data->onmax.fn_name) { 3577 ret = -ENOMEM; 3578 goto free; 3579 } 3580 out: 3581 return data; 3582 free: 3583 onmax_destroy(data); 3584 data = ERR_PTR(ret); 3585 goto out; 3586 } 3587 3588 static void onmatch_destroy(struct action_data *data) 3589 { 3590 unsigned int i; 3591 3592 lockdep_assert_held(&event_mutex); 3593 3594 kfree(data->onmatch.match_event); 3595 kfree(data->onmatch.match_event_system); 3596 kfree(data->onmatch.synth_event_name); 3597 3598 for (i = 0; i < data->n_params; i++) 3599 kfree(data->params[i]); 3600 3601 if (data->onmatch.synth_event) 3602 data->onmatch.synth_event->ref--; 3603 3604 kfree(data); 3605 } 3606 3607 static void destroy_field_var(struct field_var *field_var) 3608 { 3609 if (!field_var) 3610 return; 3611 3612 destroy_hist_field(field_var->var, 0); 3613 destroy_hist_field(field_var->val, 0); 3614 3615 kfree(field_var); 3616 } 3617 3618 static void destroy_field_vars(struct hist_trigger_data *hist_data) 3619 { 3620 unsigned int i; 3621 3622 for (i = 0; i < hist_data->n_field_vars; i++) 3623 destroy_field_var(hist_data->field_vars[i]); 3624 } 3625 3626 static void save_field_var(struct hist_trigger_data *hist_data, 3627 struct field_var *field_var) 3628 { 3629 hist_data->field_vars[hist_data->n_field_vars++] = field_var; 3630 3631 if (field_var->val->flags & HIST_FIELD_FL_STRING) 3632 hist_data->n_field_var_str++; 3633 } 3634 3635 3636 static int check_synth_field(struct synth_event *event, 3637 struct hist_field *hist_field, 3638 unsigned int field_pos) 3639 { 3640 struct synth_field *field; 3641 3642 if (field_pos >= event->n_fields) 3643 return -EINVAL; 3644 3645 field = event->fields[field_pos]; 3646 3647 if (strcmp(field->type, hist_field->type) != 0) 3648 return -EINVAL; 3649 3650 return 0; 3651 } 3652 3653 static struct hist_field * 3654 onmatch_find_var(struct hist_trigger_data *hist_data, struct action_data *data, 3655 char *system, char *event, char *var) 3656 { 3657 struct hist_field *hist_field; 3658 3659 var++; /* skip '$' */ 3660 3661 hist_field = find_target_event_var(hist_data, system, event, var); 3662 if (!hist_field) { 3663 if (!system) { 3664 system = data->onmatch.match_event_system; 3665 event = data->onmatch.match_event; 3666 } 3667 3668 hist_field = find_event_var(hist_data, system, event, var); 3669 } 3670 3671 if (!hist_field) 3672 hist_err_event("onmatch: Couldn't find onmatch param: $", system, event, var); 3673 3674 return hist_field; 3675 } 3676 3677 static struct hist_field * 3678 onmatch_create_field_var(struct hist_trigger_data *hist_data, 3679 struct action_data *data, char *system, 3680 char *event, char *var) 3681 { 3682 struct hist_field *hist_field = NULL; 3683 struct field_var *field_var; 3684 3685 /* 3686 * First try to create a field var on the target event (the 3687 * currently being defined). This will create a variable for 3688 * unqualified fields on the target event, or if qualified, 3689 * target fields that have qualified names matching the target. 3690 */ 3691 field_var = create_target_field_var(hist_data, system, event, var); 3692 3693 if (field_var && !IS_ERR(field_var)) { 3694 save_field_var(hist_data, field_var); 3695 hist_field = field_var->var; 3696 } else { 3697 field_var = NULL; 3698 /* 3699 * If no explicit system.event is specfied, default to 3700 * looking for fields on the onmatch(system.event.xxx) 3701 * event. 3702 */ 3703 if (!system) { 3704 system = data->onmatch.match_event_system; 3705 event = data->onmatch.match_event; 3706 } 3707 3708 /* 3709 * At this point, we're looking at a field on another 3710 * event. Because we can't modify a hist trigger on 3711 * another event to add a variable for a field, we need 3712 * to create a new trigger on that event and create the 3713 * variable at the same time. 3714 */ 3715 hist_field = create_field_var_hist(hist_data, system, event, var); 3716 if (IS_ERR(hist_field)) 3717 goto free; 3718 } 3719 out: 3720 return hist_field; 3721 free: 3722 destroy_field_var(field_var); 3723 hist_field = NULL; 3724 goto out; 3725 } 3726 3727 static int onmatch_create(struct hist_trigger_data *hist_data, 3728 struct trace_event_file *file, 3729 struct action_data *data) 3730 { 3731 char *event_name, *param, *system = NULL; 3732 struct hist_field *hist_field, *var_ref; 3733 unsigned int i, var_ref_idx; 3734 unsigned int field_pos = 0; 3735 struct synth_event *event; 3736 int ret = 0; 3737 3738 lockdep_assert_held(&event_mutex); 3739 3740 event = find_synth_event(data->onmatch.synth_event_name); 3741 if (!event) { 3742 hist_err("onmatch: Couldn't find synthetic event: ", data->onmatch.synth_event_name); 3743 return -EINVAL; 3744 } 3745 event->ref++; 3746 3747 var_ref_idx = hist_data->n_var_refs; 3748 3749 for (i = 0; i < data->n_params; i++) { 3750 char *p; 3751 3752 p = param = kstrdup(data->params[i], GFP_KERNEL); 3753 if (!param) { 3754 ret = -ENOMEM; 3755 goto err; 3756 } 3757 3758 system = strsep(¶m, "."); 3759 if (!param) { 3760 param = (char *)system; 3761 system = event_name = NULL; 3762 } else { 3763 event_name = strsep(¶m, "."); 3764 if (!param) { 3765 kfree(p); 3766 ret = -EINVAL; 3767 goto err; 3768 } 3769 } 3770 3771 if (param[0] == '$') 3772 hist_field = onmatch_find_var(hist_data, data, system, 3773 event_name, param); 3774 else 3775 hist_field = onmatch_create_field_var(hist_data, data, 3776 system, 3777 event_name, 3778 param); 3779 3780 if (!hist_field) { 3781 kfree(p); 3782 ret = -EINVAL; 3783 goto err; 3784 } 3785 3786 if (check_synth_field(event, hist_field, field_pos) == 0) { 3787 var_ref = create_var_ref(hist_data, hist_field, 3788 system, event_name); 3789 if (!var_ref) { 3790 kfree(p); 3791 ret = -ENOMEM; 3792 goto err; 3793 } 3794 3795 field_pos++; 3796 kfree(p); 3797 continue; 3798 } 3799 3800 hist_err_event("onmatch: Param type doesn't match synthetic event field type: ", 3801 system, event_name, param); 3802 kfree(p); 3803 ret = -EINVAL; 3804 goto err; 3805 } 3806 3807 if (field_pos != event->n_fields) { 3808 hist_err("onmatch: Param count doesn't match synthetic event field count: ", event->name); 3809 ret = -EINVAL; 3810 goto err; 3811 } 3812 3813 data->fn = action_trace; 3814 data->onmatch.synth_event = event; 3815 data->onmatch.var_ref_idx = var_ref_idx; 3816 out: 3817 return ret; 3818 err: 3819 event->ref--; 3820 3821 goto out; 3822 } 3823 3824 static struct action_data *onmatch_parse(struct trace_array *tr, char *str) 3825 { 3826 char *match_event, *match_event_system; 3827 char *synth_event_name, *params; 3828 struct action_data *data; 3829 int ret = -EINVAL; 3830 3831 data = kzalloc(sizeof(*data), GFP_KERNEL); 3832 if (!data) 3833 return ERR_PTR(-ENOMEM); 3834 3835 match_event = strsep(&str, ")"); 3836 if (!match_event || !str) { 3837 hist_err("onmatch: Missing closing paren: ", match_event); 3838 goto free; 3839 } 3840 3841 match_event_system = strsep(&match_event, "."); 3842 if (!match_event) { 3843 hist_err("onmatch: Missing subsystem for match event: ", match_event_system); 3844 goto free; 3845 } 3846 3847 if (IS_ERR(event_file(tr, match_event_system, match_event))) { 3848 hist_err_event("onmatch: Invalid subsystem or event name: ", 3849 match_event_system, match_event, NULL); 3850 goto free; 3851 } 3852 3853 data->onmatch.match_event = kstrdup(match_event, GFP_KERNEL); 3854 if (!data->onmatch.match_event) { 3855 ret = -ENOMEM; 3856 goto free; 3857 } 3858 3859 data->onmatch.match_event_system = kstrdup(match_event_system, GFP_KERNEL); 3860 if (!data->onmatch.match_event_system) { 3861 ret = -ENOMEM; 3862 goto free; 3863 } 3864 3865 strsep(&str, "."); 3866 if (!str) { 3867 hist_err("onmatch: Missing . after onmatch(): ", str); 3868 goto free; 3869 } 3870 3871 synth_event_name = strsep(&str, "("); 3872 if (!synth_event_name || !str) { 3873 hist_err("onmatch: Missing opening paramlist paren: ", synth_event_name); 3874 goto free; 3875 } 3876 3877 data->onmatch.synth_event_name = kstrdup(synth_event_name, GFP_KERNEL); 3878 if (!data->onmatch.synth_event_name) { 3879 ret = -ENOMEM; 3880 goto free; 3881 } 3882 3883 params = strsep(&str, ")"); 3884 if (!params || !str || (str && strlen(str))) { 3885 hist_err("onmatch: Missing closing paramlist paren: ", params); 3886 goto free; 3887 } 3888 3889 ret = parse_action_params(params, data); 3890 if (ret) 3891 goto free; 3892 out: 3893 return data; 3894 free: 3895 onmatch_destroy(data); 3896 data = ERR_PTR(ret); 3897 goto out; 3898 } 3899 3900 static int create_hitcount_val(struct hist_trigger_data *hist_data) 3901 { 3902 hist_data->fields[HITCOUNT_IDX] = 3903 create_hist_field(hist_data, NULL, HIST_FIELD_FL_HITCOUNT, NULL); 3904 if (!hist_data->fields[HITCOUNT_IDX]) 3905 return -ENOMEM; 3906 3907 hist_data->n_vals++; 3908 hist_data->n_fields++; 3909 3910 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX)) 3911 return -EINVAL; 3912 3913 return 0; 3914 } 3915 3916 static int __create_val_field(struct hist_trigger_data *hist_data, 3917 unsigned int val_idx, 3918 struct trace_event_file *file, 3919 char *var_name, char *field_str, 3920 unsigned long flags) 3921 { 3922 struct hist_field *hist_field; 3923 int ret = 0; 3924 3925 hist_field = parse_expr(hist_data, file, field_str, flags, var_name, 0); 3926 if (IS_ERR(hist_field)) { 3927 ret = PTR_ERR(hist_field); 3928 goto out; 3929 } 3930 3931 hist_data->fields[val_idx] = hist_field; 3932 3933 ++hist_data->n_vals; 3934 ++hist_data->n_fields; 3935 3936 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX)) 3937 ret = -EINVAL; 3938 out: 3939 return ret; 3940 } 3941 3942 static int create_val_field(struct hist_trigger_data *hist_data, 3943 unsigned int val_idx, 3944 struct trace_event_file *file, 3945 char *field_str) 3946 { 3947 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX)) 3948 return -EINVAL; 3949 3950 return __create_val_field(hist_data, val_idx, file, NULL, field_str, 0); 3951 } 3952 3953 static int create_var_field(struct hist_trigger_data *hist_data, 3954 unsigned int val_idx, 3955 struct trace_event_file *file, 3956 char *var_name, char *expr_str) 3957 { 3958 unsigned long flags = 0; 3959 3960 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX)) 3961 return -EINVAL; 3962 3963 if (find_var(hist_data, file, var_name) && !hist_data->remove) { 3964 hist_err("Variable already defined: ", var_name); 3965 return -EINVAL; 3966 } 3967 3968 flags |= HIST_FIELD_FL_VAR; 3969 hist_data->n_vars++; 3970 if (WARN_ON(hist_data->n_vars > TRACING_MAP_VARS_MAX)) 3971 return -EINVAL; 3972 3973 return __create_val_field(hist_data, val_idx, file, var_name, expr_str, flags); 3974 } 3975 3976 static int create_val_fields(struct hist_trigger_data *hist_data, 3977 struct trace_event_file *file) 3978 { 3979 char *fields_str, *field_str; 3980 unsigned int i, j = 1; 3981 int ret; 3982 3983 ret = create_hitcount_val(hist_data); 3984 if (ret) 3985 goto out; 3986 3987 fields_str = hist_data->attrs->vals_str; 3988 if (!fields_str) 3989 goto out; 3990 3991 strsep(&fields_str, "="); 3992 if (!fields_str) 3993 goto out; 3994 3995 for (i = 0, j = 1; i < TRACING_MAP_VALS_MAX && 3996 j < TRACING_MAP_VALS_MAX; i++) { 3997 field_str = strsep(&fields_str, ","); 3998 if (!field_str) 3999 break; 4000 4001 if (strcmp(field_str, "hitcount") == 0) 4002 continue; 4003 4004 ret = create_val_field(hist_data, j++, file, field_str); 4005 if (ret) 4006 goto out; 4007 } 4008 4009 if (fields_str && (strcmp(fields_str, "hitcount") != 0)) 4010 ret = -EINVAL; 4011 out: 4012 return ret; 4013 } 4014 4015 static int create_key_field(struct hist_trigger_data *hist_data, 4016 unsigned int key_idx, 4017 unsigned int key_offset, 4018 struct trace_event_file *file, 4019 char *field_str) 4020 { 4021 struct hist_field *hist_field = NULL; 4022 4023 unsigned long flags = 0; 4024 unsigned int key_size; 4025 int ret = 0; 4026 4027 if (WARN_ON(key_idx >= HIST_FIELDS_MAX)) 4028 return -EINVAL; 4029 4030 flags |= HIST_FIELD_FL_KEY; 4031 4032 if (strcmp(field_str, "stacktrace") == 0) { 4033 flags |= HIST_FIELD_FL_STACKTRACE; 4034 key_size = sizeof(unsigned long) * HIST_STACKTRACE_DEPTH; 4035 hist_field = create_hist_field(hist_data, NULL, flags, NULL); 4036 } else { 4037 hist_field = parse_expr(hist_data, file, field_str, flags, 4038 NULL, 0); 4039 if (IS_ERR(hist_field)) { 4040 ret = PTR_ERR(hist_field); 4041 goto out; 4042 } 4043 4044 if (hist_field->flags & HIST_FIELD_FL_VAR_REF) { 4045 hist_err("Using variable references as keys not supported: ", field_str); 4046 destroy_hist_field(hist_field, 0); 4047 ret = -EINVAL; 4048 goto out; 4049 } 4050 4051 key_size = hist_field->size; 4052 } 4053 4054 hist_data->fields[key_idx] = hist_field; 4055 4056 key_size = ALIGN(key_size, sizeof(u64)); 4057 hist_data->fields[key_idx]->size = key_size; 4058 hist_data->fields[key_idx]->offset = key_offset; 4059 4060 hist_data->key_size += key_size; 4061 4062 if (hist_data->key_size > HIST_KEY_SIZE_MAX) { 4063 ret = -EINVAL; 4064 goto out; 4065 } 4066 4067 hist_data->n_keys++; 4068 hist_data->n_fields++; 4069 4070 if (WARN_ON(hist_data->n_keys > TRACING_MAP_KEYS_MAX)) 4071 return -EINVAL; 4072 4073 ret = key_size; 4074 out: 4075 return ret; 4076 } 4077 4078 static int create_key_fields(struct hist_trigger_data *hist_data, 4079 struct trace_event_file *file) 4080 { 4081 unsigned int i, key_offset = 0, n_vals = hist_data->n_vals; 4082 char *fields_str, *field_str; 4083 int ret = -EINVAL; 4084 4085 fields_str = hist_data->attrs->keys_str; 4086 if (!fields_str) 4087 goto out; 4088 4089 strsep(&fields_str, "="); 4090 if (!fields_str) 4091 goto out; 4092 4093 for (i = n_vals; i < n_vals + TRACING_MAP_KEYS_MAX; i++) { 4094 field_str = strsep(&fields_str, ","); 4095 if (!field_str) 4096 break; 4097 ret = create_key_field(hist_data, i, key_offset, 4098 file, field_str); 4099 if (ret < 0) 4100 goto out; 4101 key_offset += ret; 4102 } 4103 if (fields_str) { 4104 ret = -EINVAL; 4105 goto out; 4106 } 4107 ret = 0; 4108 out: 4109 return ret; 4110 } 4111 4112 static int create_var_fields(struct hist_trigger_data *hist_data, 4113 struct trace_event_file *file) 4114 { 4115 unsigned int i, j = hist_data->n_vals; 4116 int ret = 0; 4117 4118 unsigned int n_vars = hist_data->attrs->var_defs.n_vars; 4119 4120 for (i = 0; i < n_vars; i++) { 4121 char *var_name = hist_data->attrs->var_defs.name[i]; 4122 char *expr = hist_data->attrs->var_defs.expr[i]; 4123 4124 ret = create_var_field(hist_data, j++, file, var_name, expr); 4125 if (ret) 4126 goto out; 4127 } 4128 out: 4129 return ret; 4130 } 4131 4132 static void free_var_defs(struct hist_trigger_data *hist_data) 4133 { 4134 unsigned int i; 4135 4136 for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) { 4137 kfree(hist_data->attrs->var_defs.name[i]); 4138 kfree(hist_data->attrs->var_defs.expr[i]); 4139 } 4140 4141 hist_data->attrs->var_defs.n_vars = 0; 4142 } 4143 4144 static int parse_var_defs(struct hist_trigger_data *hist_data) 4145 { 4146 char *s, *str, *var_name, *field_str; 4147 unsigned int i, j, n_vars = 0; 4148 int ret = 0; 4149 4150 for (i = 0; i < hist_data->attrs->n_assignments; i++) { 4151 str = hist_data->attrs->assignment_str[i]; 4152 for (j = 0; j < TRACING_MAP_VARS_MAX; j++) { 4153 field_str = strsep(&str, ","); 4154 if (!field_str) 4155 break; 4156 4157 var_name = strsep(&field_str, "="); 4158 if (!var_name || !field_str) { 4159 hist_err("Malformed assignment: ", var_name); 4160 ret = -EINVAL; 4161 goto free; 4162 } 4163 4164 if (n_vars == TRACING_MAP_VARS_MAX) { 4165 hist_err("Too many variables defined: ", var_name); 4166 ret = -EINVAL; 4167 goto free; 4168 } 4169 4170 s = kstrdup(var_name, GFP_KERNEL); 4171 if (!s) { 4172 ret = -ENOMEM; 4173 goto free; 4174 } 4175 hist_data->attrs->var_defs.name[n_vars] = s; 4176 4177 s = kstrdup(field_str, GFP_KERNEL); 4178 if (!s) { 4179 kfree(hist_data->attrs->var_defs.name[n_vars]); 4180 ret = -ENOMEM; 4181 goto free; 4182 } 4183 hist_data->attrs->var_defs.expr[n_vars++] = s; 4184 4185 hist_data->attrs->var_defs.n_vars = n_vars; 4186 } 4187 } 4188 4189 return ret; 4190 free: 4191 free_var_defs(hist_data); 4192 4193 return ret; 4194 } 4195 4196 static int create_hist_fields(struct hist_trigger_data *hist_data, 4197 struct trace_event_file *file) 4198 { 4199 int ret; 4200 4201 ret = parse_var_defs(hist_data); 4202 if (ret) 4203 goto out; 4204 4205 ret = create_val_fields(hist_data, file); 4206 if (ret) 4207 goto out; 4208 4209 ret = create_var_fields(hist_data, file); 4210 if (ret) 4211 goto out; 4212 4213 ret = create_key_fields(hist_data, file); 4214 if (ret) 4215 goto out; 4216 out: 4217 free_var_defs(hist_data); 4218 4219 return ret; 4220 } 4221 4222 static int is_descending(const char *str) 4223 { 4224 if (!str) 4225 return 0; 4226 4227 if (strcmp(str, "descending") == 0) 4228 return 1; 4229 4230 if (strcmp(str, "ascending") == 0) 4231 return 0; 4232 4233 return -EINVAL; 4234 } 4235 4236 static int create_sort_keys(struct hist_trigger_data *hist_data) 4237 { 4238 char *fields_str = hist_data->attrs->sort_key_str; 4239 struct tracing_map_sort_key *sort_key; 4240 int descending, ret = 0; 4241 unsigned int i, j, k; 4242 4243 hist_data->n_sort_keys = 1; /* we always have at least one, hitcount */ 4244 4245 if (!fields_str) 4246 goto out; 4247 4248 strsep(&fields_str, "="); 4249 if (!fields_str) { 4250 ret = -EINVAL; 4251 goto out; 4252 } 4253 4254 for (i = 0; i < TRACING_MAP_SORT_KEYS_MAX; i++) { 4255 struct hist_field *hist_field; 4256 char *field_str, *field_name; 4257 const char *test_name; 4258 4259 sort_key = &hist_data->sort_keys[i]; 4260 4261 field_str = strsep(&fields_str, ","); 4262 if (!field_str) { 4263 if (i == 0) 4264 ret = -EINVAL; 4265 break; 4266 } 4267 4268 if ((i == TRACING_MAP_SORT_KEYS_MAX - 1) && fields_str) { 4269 ret = -EINVAL; 4270 break; 4271 } 4272 4273 field_name = strsep(&field_str, "."); 4274 if (!field_name) { 4275 ret = -EINVAL; 4276 break; 4277 } 4278 4279 if (strcmp(field_name, "hitcount") == 0) { 4280 descending = is_descending(field_str); 4281 if (descending < 0) { 4282 ret = descending; 4283 break; 4284 } 4285 sort_key->descending = descending; 4286 continue; 4287 } 4288 4289 for (j = 1, k = 1; j < hist_data->n_fields; j++) { 4290 unsigned int idx; 4291 4292 hist_field = hist_data->fields[j]; 4293 if (hist_field->flags & HIST_FIELD_FL_VAR) 4294 continue; 4295 4296 idx = k++; 4297 4298 test_name = hist_field_name(hist_field, 0); 4299 4300 if (strcmp(field_name, test_name) == 0) { 4301 sort_key->field_idx = idx; 4302 descending = is_descending(field_str); 4303 if (descending < 0) { 4304 ret = descending; 4305 goto out; 4306 } 4307 sort_key->descending = descending; 4308 break; 4309 } 4310 } 4311 if (j == hist_data->n_fields) { 4312 ret = -EINVAL; 4313 break; 4314 } 4315 } 4316 4317 hist_data->n_sort_keys = i; 4318 out: 4319 return ret; 4320 } 4321 4322 static void destroy_actions(struct hist_trigger_data *hist_data) 4323 { 4324 unsigned int i; 4325 4326 for (i = 0; i < hist_data->n_actions; i++) { 4327 struct action_data *data = hist_data->actions[i]; 4328 4329 if (data->fn == action_trace) 4330 onmatch_destroy(data); 4331 else if (data->fn == onmax_save) 4332 onmax_destroy(data); 4333 else 4334 kfree(data); 4335 } 4336 } 4337 4338 static int parse_actions(struct hist_trigger_data *hist_data) 4339 { 4340 struct trace_array *tr = hist_data->event_file->tr; 4341 struct action_data *data; 4342 unsigned int i; 4343 int ret = 0; 4344 char *str; 4345 int len; 4346 4347 for (i = 0; i < hist_data->attrs->n_actions; i++) { 4348 str = hist_data->attrs->action_str[i]; 4349 4350 if ((len = str_has_prefix(str, "onmatch("))) { 4351 char *action_str = str + len; 4352 4353 data = onmatch_parse(tr, action_str); 4354 if (IS_ERR(data)) { 4355 ret = PTR_ERR(data); 4356 break; 4357 } 4358 data->fn = action_trace; 4359 } else if ((len = str_has_prefix(str, "onmax("))) { 4360 char *action_str = str + len; 4361 4362 data = onmax_parse(action_str); 4363 if (IS_ERR(data)) { 4364 ret = PTR_ERR(data); 4365 break; 4366 } 4367 data->fn = onmax_save; 4368 } else { 4369 ret = -EINVAL; 4370 break; 4371 } 4372 4373 hist_data->actions[hist_data->n_actions++] = data; 4374 } 4375 4376 return ret; 4377 } 4378 4379 static int create_actions(struct hist_trigger_data *hist_data, 4380 struct trace_event_file *file) 4381 { 4382 struct action_data *data; 4383 unsigned int i; 4384 int ret = 0; 4385 4386 for (i = 0; i < hist_data->attrs->n_actions; i++) { 4387 data = hist_data->actions[i]; 4388 4389 if (data->fn == action_trace) { 4390 ret = onmatch_create(hist_data, file, data); 4391 if (ret) 4392 return ret; 4393 } else if (data->fn == onmax_save) { 4394 ret = onmax_create(hist_data, data); 4395 if (ret) 4396 return ret; 4397 } 4398 } 4399 4400 return ret; 4401 } 4402 4403 static void print_actions(struct seq_file *m, 4404 struct hist_trigger_data *hist_data, 4405 struct tracing_map_elt *elt) 4406 { 4407 unsigned int i; 4408 4409 for (i = 0; i < hist_data->n_actions; i++) { 4410 struct action_data *data = hist_data->actions[i]; 4411 4412 if (data->fn == onmax_save) 4413 onmax_print(m, hist_data, elt, data); 4414 } 4415 } 4416 4417 static void print_onmax_spec(struct seq_file *m, 4418 struct hist_trigger_data *hist_data, 4419 struct action_data *data) 4420 { 4421 unsigned int i; 4422 4423 seq_puts(m, ":onmax("); 4424 seq_printf(m, "%s", data->onmax.var_str); 4425 seq_printf(m, ").%s(", data->onmax.fn_name); 4426 4427 for (i = 0; i < hist_data->n_max_vars; i++) { 4428 seq_printf(m, "%s", hist_data->max_vars[i]->var->var.name); 4429 if (i < hist_data->n_max_vars - 1) 4430 seq_puts(m, ","); 4431 } 4432 seq_puts(m, ")"); 4433 } 4434 4435 static void print_onmatch_spec(struct seq_file *m, 4436 struct hist_trigger_data *hist_data, 4437 struct action_data *data) 4438 { 4439 unsigned int i; 4440 4441 seq_printf(m, ":onmatch(%s.%s).", data->onmatch.match_event_system, 4442 data->onmatch.match_event); 4443 4444 seq_printf(m, "%s(", data->onmatch.synth_event->name); 4445 4446 for (i = 0; i < data->n_params; i++) { 4447 if (i) 4448 seq_puts(m, ","); 4449 seq_printf(m, "%s", data->params[i]); 4450 } 4451 4452 seq_puts(m, ")"); 4453 } 4454 4455 static bool actions_match(struct hist_trigger_data *hist_data, 4456 struct hist_trigger_data *hist_data_test) 4457 { 4458 unsigned int i, j; 4459 4460 if (hist_data->n_actions != hist_data_test->n_actions) 4461 return false; 4462 4463 for (i = 0; i < hist_data->n_actions; i++) { 4464 struct action_data *data = hist_data->actions[i]; 4465 struct action_data *data_test = hist_data_test->actions[i]; 4466 4467 if (data->fn != data_test->fn) 4468 return false; 4469 4470 if (data->n_params != data_test->n_params) 4471 return false; 4472 4473 for (j = 0; j < data->n_params; j++) { 4474 if (strcmp(data->params[j], data_test->params[j]) != 0) 4475 return false; 4476 } 4477 4478 if (data->fn == action_trace) { 4479 if (strcmp(data->onmatch.synth_event_name, 4480 data_test->onmatch.synth_event_name) != 0) 4481 return false; 4482 if (strcmp(data->onmatch.match_event_system, 4483 data_test->onmatch.match_event_system) != 0) 4484 return false; 4485 if (strcmp(data->onmatch.match_event, 4486 data_test->onmatch.match_event) != 0) 4487 return false; 4488 } else if (data->fn == onmax_save) { 4489 if (strcmp(data->onmax.var_str, 4490 data_test->onmax.var_str) != 0) 4491 return false; 4492 if (strcmp(data->onmax.fn_name, 4493 data_test->onmax.fn_name) != 0) 4494 return false; 4495 } 4496 } 4497 4498 return true; 4499 } 4500 4501 4502 static void print_actions_spec(struct seq_file *m, 4503 struct hist_trigger_data *hist_data) 4504 { 4505 unsigned int i; 4506 4507 for (i = 0; i < hist_data->n_actions; i++) { 4508 struct action_data *data = hist_data->actions[i]; 4509 4510 if (data->fn == action_trace) 4511 print_onmatch_spec(m, hist_data, data); 4512 else if (data->fn == onmax_save) 4513 print_onmax_spec(m, hist_data, data); 4514 } 4515 } 4516 4517 static void destroy_field_var_hists(struct hist_trigger_data *hist_data) 4518 { 4519 unsigned int i; 4520 4521 for (i = 0; i < hist_data->n_field_var_hists; i++) { 4522 kfree(hist_data->field_var_hists[i]->cmd); 4523 kfree(hist_data->field_var_hists[i]); 4524 } 4525 } 4526 4527 static void destroy_hist_data(struct hist_trigger_data *hist_data) 4528 { 4529 if (!hist_data) 4530 return; 4531 4532 destroy_hist_trigger_attrs(hist_data->attrs); 4533 destroy_hist_fields(hist_data); 4534 tracing_map_destroy(hist_data->map); 4535 4536 destroy_actions(hist_data); 4537 destroy_field_vars(hist_data); 4538 destroy_field_var_hists(hist_data); 4539 4540 kfree(hist_data); 4541 } 4542 4543 static int create_tracing_map_fields(struct hist_trigger_data *hist_data) 4544 { 4545 struct tracing_map *map = hist_data->map; 4546 struct ftrace_event_field *field; 4547 struct hist_field *hist_field; 4548 int i, idx = 0; 4549 4550 for_each_hist_field(i, hist_data) { 4551 hist_field = hist_data->fields[i]; 4552 if (hist_field->flags & HIST_FIELD_FL_KEY) { 4553 tracing_map_cmp_fn_t cmp_fn; 4554 4555 field = hist_field->field; 4556 4557 if (hist_field->flags & HIST_FIELD_FL_STACKTRACE) 4558 cmp_fn = tracing_map_cmp_none; 4559 else if (!field) 4560 cmp_fn = tracing_map_cmp_num(hist_field->size, 4561 hist_field->is_signed); 4562 else if (is_string_field(field)) 4563 cmp_fn = tracing_map_cmp_string; 4564 else 4565 cmp_fn = tracing_map_cmp_num(field->size, 4566 field->is_signed); 4567 idx = tracing_map_add_key_field(map, 4568 hist_field->offset, 4569 cmp_fn); 4570 } else if (!(hist_field->flags & HIST_FIELD_FL_VAR)) 4571 idx = tracing_map_add_sum_field(map); 4572 4573 if (idx < 0) 4574 return idx; 4575 4576 if (hist_field->flags & HIST_FIELD_FL_VAR) { 4577 idx = tracing_map_add_var(map); 4578 if (idx < 0) 4579 return idx; 4580 hist_field->var.idx = idx; 4581 hist_field->var.hist_data = hist_data; 4582 } 4583 } 4584 4585 return 0; 4586 } 4587 4588 static struct hist_trigger_data * 4589 create_hist_data(unsigned int map_bits, 4590 struct hist_trigger_attrs *attrs, 4591 struct trace_event_file *file, 4592 bool remove) 4593 { 4594 const struct tracing_map_ops *map_ops = NULL; 4595 struct hist_trigger_data *hist_data; 4596 int ret = 0; 4597 4598 hist_data = kzalloc(sizeof(*hist_data), GFP_KERNEL); 4599 if (!hist_data) 4600 return ERR_PTR(-ENOMEM); 4601 4602 hist_data->attrs = attrs; 4603 hist_data->remove = remove; 4604 hist_data->event_file = file; 4605 4606 ret = parse_actions(hist_data); 4607 if (ret) 4608 goto free; 4609 4610 ret = create_hist_fields(hist_data, file); 4611 if (ret) 4612 goto free; 4613 4614 ret = create_sort_keys(hist_data); 4615 if (ret) 4616 goto free; 4617 4618 map_ops = &hist_trigger_elt_data_ops; 4619 4620 hist_data->map = tracing_map_create(map_bits, hist_data->key_size, 4621 map_ops, hist_data); 4622 if (IS_ERR(hist_data->map)) { 4623 ret = PTR_ERR(hist_data->map); 4624 hist_data->map = NULL; 4625 goto free; 4626 } 4627 4628 ret = create_tracing_map_fields(hist_data); 4629 if (ret) 4630 goto free; 4631 out: 4632 return hist_data; 4633 free: 4634 hist_data->attrs = NULL; 4635 4636 destroy_hist_data(hist_data); 4637 4638 hist_data = ERR_PTR(ret); 4639 4640 goto out; 4641 } 4642 4643 static void hist_trigger_elt_update(struct hist_trigger_data *hist_data, 4644 struct tracing_map_elt *elt, void *rec, 4645 struct ring_buffer_event *rbe, 4646 u64 *var_ref_vals) 4647 { 4648 struct hist_elt_data *elt_data; 4649 struct hist_field *hist_field; 4650 unsigned int i, var_idx; 4651 u64 hist_val; 4652 4653 elt_data = elt->private_data; 4654 elt_data->var_ref_vals = var_ref_vals; 4655 4656 for_each_hist_val_field(i, hist_data) { 4657 hist_field = hist_data->fields[i]; 4658 hist_val = hist_field->fn(hist_field, elt, rbe, rec); 4659 if (hist_field->flags & HIST_FIELD_FL_VAR) { 4660 var_idx = hist_field->var.idx; 4661 tracing_map_set_var(elt, var_idx, hist_val); 4662 continue; 4663 } 4664 tracing_map_update_sum(elt, i, hist_val); 4665 } 4666 4667 for_each_hist_key_field(i, hist_data) { 4668 hist_field = hist_data->fields[i]; 4669 if (hist_field->flags & HIST_FIELD_FL_VAR) { 4670 hist_val = hist_field->fn(hist_field, elt, rbe, rec); 4671 var_idx = hist_field->var.idx; 4672 tracing_map_set_var(elt, var_idx, hist_val); 4673 } 4674 } 4675 4676 update_field_vars(hist_data, elt, rbe, rec); 4677 } 4678 4679 static inline void add_to_key(char *compound_key, void *key, 4680 struct hist_field *key_field, void *rec) 4681 { 4682 size_t size = key_field->size; 4683 4684 if (key_field->flags & HIST_FIELD_FL_STRING) { 4685 struct ftrace_event_field *field; 4686 4687 field = key_field->field; 4688 if (field->filter_type == FILTER_DYN_STRING) 4689 size = *(u32 *)(rec + field->offset) >> 16; 4690 else if (field->filter_type == FILTER_PTR_STRING) 4691 size = strlen(key); 4692 else if (field->filter_type == FILTER_STATIC_STRING) 4693 size = field->size; 4694 4695 /* ensure NULL-termination */ 4696 if (size > key_field->size - 1) 4697 size = key_field->size - 1; 4698 } 4699 4700 memcpy(compound_key + key_field->offset, key, size); 4701 } 4702 4703 static void 4704 hist_trigger_actions(struct hist_trigger_data *hist_data, 4705 struct tracing_map_elt *elt, void *rec, 4706 struct ring_buffer_event *rbe, u64 *var_ref_vals) 4707 { 4708 struct action_data *data; 4709 unsigned int i; 4710 4711 for (i = 0; i < hist_data->n_actions; i++) { 4712 data = hist_data->actions[i]; 4713 data->fn(hist_data, elt, rec, rbe, data, var_ref_vals); 4714 } 4715 } 4716 4717 static void event_hist_trigger(struct event_trigger_data *data, void *rec, 4718 struct ring_buffer_event *rbe) 4719 { 4720 struct hist_trigger_data *hist_data = data->private_data; 4721 bool use_compound_key = (hist_data->n_keys > 1); 4722 unsigned long entries[HIST_STACKTRACE_DEPTH]; 4723 u64 var_ref_vals[TRACING_MAP_VARS_MAX]; 4724 char compound_key[HIST_KEY_SIZE_MAX]; 4725 struct tracing_map_elt *elt = NULL; 4726 struct stack_trace stacktrace; 4727 struct hist_field *key_field; 4728 u64 field_contents; 4729 void *key = NULL; 4730 unsigned int i; 4731 4732 memset(compound_key, 0, hist_data->key_size); 4733 4734 for_each_hist_key_field(i, hist_data) { 4735 key_field = hist_data->fields[i]; 4736 4737 if (key_field->flags & HIST_FIELD_FL_STACKTRACE) { 4738 stacktrace.max_entries = HIST_STACKTRACE_DEPTH; 4739 stacktrace.entries = entries; 4740 stacktrace.nr_entries = 0; 4741 stacktrace.skip = HIST_STACKTRACE_SKIP; 4742 4743 memset(stacktrace.entries, 0, HIST_STACKTRACE_SIZE); 4744 save_stack_trace(&stacktrace); 4745 4746 key = entries; 4747 } else { 4748 field_contents = key_field->fn(key_field, elt, rbe, rec); 4749 if (key_field->flags & HIST_FIELD_FL_STRING) { 4750 key = (void *)(unsigned long)field_contents; 4751 use_compound_key = true; 4752 } else 4753 key = (void *)&field_contents; 4754 } 4755 4756 if (use_compound_key) 4757 add_to_key(compound_key, key, key_field, rec); 4758 } 4759 4760 if (use_compound_key) 4761 key = compound_key; 4762 4763 if (hist_data->n_var_refs && 4764 !resolve_var_refs(hist_data, key, var_ref_vals, false)) 4765 return; 4766 4767 elt = tracing_map_insert(hist_data->map, key); 4768 if (!elt) 4769 return; 4770 4771 hist_trigger_elt_update(hist_data, elt, rec, rbe, var_ref_vals); 4772 4773 if (resolve_var_refs(hist_data, key, var_ref_vals, true)) 4774 hist_trigger_actions(hist_data, elt, rec, rbe, var_ref_vals); 4775 } 4776 4777 static void hist_trigger_stacktrace_print(struct seq_file *m, 4778 unsigned long *stacktrace_entries, 4779 unsigned int max_entries) 4780 { 4781 char str[KSYM_SYMBOL_LEN]; 4782 unsigned int spaces = 8; 4783 unsigned int i; 4784 4785 for (i = 0; i < max_entries; i++) { 4786 if (stacktrace_entries[i] == ULONG_MAX) 4787 return; 4788 4789 seq_printf(m, "%*c", 1 + spaces, ' '); 4790 sprint_symbol(str, stacktrace_entries[i]); 4791 seq_printf(m, "%s\n", str); 4792 } 4793 } 4794 4795 static void 4796 hist_trigger_entry_print(struct seq_file *m, 4797 struct hist_trigger_data *hist_data, void *key, 4798 struct tracing_map_elt *elt) 4799 { 4800 struct hist_field *key_field; 4801 char str[KSYM_SYMBOL_LEN]; 4802 bool multiline = false; 4803 const char *field_name; 4804 unsigned int i; 4805 u64 uval; 4806 4807 seq_puts(m, "{ "); 4808 4809 for_each_hist_key_field(i, hist_data) { 4810 key_field = hist_data->fields[i]; 4811 4812 if (i > hist_data->n_vals) 4813 seq_puts(m, ", "); 4814 4815 field_name = hist_field_name(key_field, 0); 4816 4817 if (key_field->flags & HIST_FIELD_FL_HEX) { 4818 uval = *(u64 *)(key + key_field->offset); 4819 seq_printf(m, "%s: %llx", field_name, uval); 4820 } else if (key_field->flags & HIST_FIELD_FL_SYM) { 4821 uval = *(u64 *)(key + key_field->offset); 4822 sprint_symbol_no_offset(str, uval); 4823 seq_printf(m, "%s: [%llx] %-45s", field_name, 4824 uval, str); 4825 } else if (key_field->flags & HIST_FIELD_FL_SYM_OFFSET) { 4826 uval = *(u64 *)(key + key_field->offset); 4827 sprint_symbol(str, uval); 4828 seq_printf(m, "%s: [%llx] %-55s", field_name, 4829 uval, str); 4830 } else if (key_field->flags & HIST_FIELD_FL_EXECNAME) { 4831 struct hist_elt_data *elt_data = elt->private_data; 4832 char *comm; 4833 4834 if (WARN_ON_ONCE(!elt_data)) 4835 return; 4836 4837 comm = elt_data->comm; 4838 4839 uval = *(u64 *)(key + key_field->offset); 4840 seq_printf(m, "%s: %-16s[%10llu]", field_name, 4841 comm, uval); 4842 } else if (key_field->flags & HIST_FIELD_FL_SYSCALL) { 4843 const char *syscall_name; 4844 4845 uval = *(u64 *)(key + key_field->offset); 4846 syscall_name = get_syscall_name(uval); 4847 if (!syscall_name) 4848 syscall_name = "unknown_syscall"; 4849 4850 seq_printf(m, "%s: %-30s[%3llu]", field_name, 4851 syscall_name, uval); 4852 } else if (key_field->flags & HIST_FIELD_FL_STACKTRACE) { 4853 seq_puts(m, "stacktrace:\n"); 4854 hist_trigger_stacktrace_print(m, 4855 key + key_field->offset, 4856 HIST_STACKTRACE_DEPTH); 4857 multiline = true; 4858 } else if (key_field->flags & HIST_FIELD_FL_LOG2) { 4859 seq_printf(m, "%s: ~ 2^%-2llu", field_name, 4860 *(u64 *)(key + key_field->offset)); 4861 } else if (key_field->flags & HIST_FIELD_FL_STRING) { 4862 seq_printf(m, "%s: %-50s", field_name, 4863 (char *)(key + key_field->offset)); 4864 } else { 4865 uval = *(u64 *)(key + key_field->offset); 4866 seq_printf(m, "%s: %10llu", field_name, uval); 4867 } 4868 } 4869 4870 if (!multiline) 4871 seq_puts(m, " "); 4872 4873 seq_puts(m, "}"); 4874 4875 seq_printf(m, " hitcount: %10llu", 4876 tracing_map_read_sum(elt, HITCOUNT_IDX)); 4877 4878 for (i = 1; i < hist_data->n_vals; i++) { 4879 field_name = hist_field_name(hist_data->fields[i], 0); 4880 4881 if (hist_data->fields[i]->flags & HIST_FIELD_FL_VAR || 4882 hist_data->fields[i]->flags & HIST_FIELD_FL_EXPR) 4883 continue; 4884 4885 if (hist_data->fields[i]->flags & HIST_FIELD_FL_HEX) { 4886 seq_printf(m, " %s: %10llx", field_name, 4887 tracing_map_read_sum(elt, i)); 4888 } else { 4889 seq_printf(m, " %s: %10llu", field_name, 4890 tracing_map_read_sum(elt, i)); 4891 } 4892 } 4893 4894 print_actions(m, hist_data, elt); 4895 4896 seq_puts(m, "\n"); 4897 } 4898 4899 static int print_entries(struct seq_file *m, 4900 struct hist_trigger_data *hist_data) 4901 { 4902 struct tracing_map_sort_entry **sort_entries = NULL; 4903 struct tracing_map *map = hist_data->map; 4904 int i, n_entries; 4905 4906 n_entries = tracing_map_sort_entries(map, hist_data->sort_keys, 4907 hist_data->n_sort_keys, 4908 &sort_entries); 4909 if (n_entries < 0) 4910 return n_entries; 4911 4912 for (i = 0; i < n_entries; i++) 4913 hist_trigger_entry_print(m, hist_data, 4914 sort_entries[i]->key, 4915 sort_entries[i]->elt); 4916 4917 tracing_map_destroy_sort_entries(sort_entries, n_entries); 4918 4919 return n_entries; 4920 } 4921 4922 static void hist_trigger_show(struct seq_file *m, 4923 struct event_trigger_data *data, int n) 4924 { 4925 struct hist_trigger_data *hist_data; 4926 int n_entries; 4927 4928 if (n > 0) 4929 seq_puts(m, "\n\n"); 4930 4931 seq_puts(m, "# event histogram\n#\n# trigger info: "); 4932 data->ops->print(m, data->ops, data); 4933 seq_puts(m, "#\n\n"); 4934 4935 hist_data = data->private_data; 4936 n_entries = print_entries(m, hist_data); 4937 if (n_entries < 0) 4938 n_entries = 0; 4939 4940 seq_printf(m, "\nTotals:\n Hits: %llu\n Entries: %u\n Dropped: %llu\n", 4941 (u64)atomic64_read(&hist_data->map->hits), 4942 n_entries, (u64)atomic64_read(&hist_data->map->drops)); 4943 } 4944 4945 static int hist_show(struct seq_file *m, void *v) 4946 { 4947 struct event_trigger_data *data; 4948 struct trace_event_file *event_file; 4949 int n = 0, ret = 0; 4950 4951 mutex_lock(&event_mutex); 4952 4953 event_file = event_file_data(m->private); 4954 if (unlikely(!event_file)) { 4955 ret = -ENODEV; 4956 goto out_unlock; 4957 } 4958 4959 list_for_each_entry_rcu(data, &event_file->triggers, list) { 4960 if (data->cmd_ops->trigger_type == ETT_EVENT_HIST) 4961 hist_trigger_show(m, data, n++); 4962 } 4963 4964 if (have_hist_err()) { 4965 seq_printf(m, "\nERROR: %s\n", hist_err_str); 4966 seq_printf(m, " Last command: %s\n", last_hist_cmd); 4967 } 4968 4969 out_unlock: 4970 mutex_unlock(&event_mutex); 4971 4972 return ret; 4973 } 4974 4975 static int event_hist_open(struct inode *inode, struct file *file) 4976 { 4977 return single_open(file, hist_show, file); 4978 } 4979 4980 const struct file_operations event_hist_fops = { 4981 .open = event_hist_open, 4982 .read = seq_read, 4983 .llseek = seq_lseek, 4984 .release = single_release, 4985 }; 4986 4987 static void hist_field_print(struct seq_file *m, struct hist_field *hist_field) 4988 { 4989 const char *field_name = hist_field_name(hist_field, 0); 4990 4991 if (hist_field->var.name) 4992 seq_printf(m, "%s=", hist_field->var.name); 4993 4994 if (hist_field->flags & HIST_FIELD_FL_CPU) 4995 seq_puts(m, "cpu"); 4996 else if (field_name) { 4997 if (hist_field->flags & HIST_FIELD_FL_VAR_REF || 4998 hist_field->flags & HIST_FIELD_FL_ALIAS) 4999 seq_putc(m, '$'); 5000 seq_printf(m, "%s", field_name); 5001 } else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP) 5002 seq_puts(m, "common_timestamp"); 5003 5004 if (hist_field->flags) { 5005 if (!(hist_field->flags & HIST_FIELD_FL_VAR_REF) && 5006 !(hist_field->flags & HIST_FIELD_FL_EXPR)) { 5007 const char *flags = get_hist_field_flags(hist_field); 5008 5009 if (flags) 5010 seq_printf(m, ".%s", flags); 5011 } 5012 } 5013 } 5014 5015 static int event_hist_trigger_print(struct seq_file *m, 5016 struct event_trigger_ops *ops, 5017 struct event_trigger_data *data) 5018 { 5019 struct hist_trigger_data *hist_data = data->private_data; 5020 struct hist_field *field; 5021 bool have_var = false; 5022 unsigned int i; 5023 5024 seq_puts(m, "hist:"); 5025 5026 if (data->name) 5027 seq_printf(m, "%s:", data->name); 5028 5029 seq_puts(m, "keys="); 5030 5031 for_each_hist_key_field(i, hist_data) { 5032 field = hist_data->fields[i]; 5033 5034 if (i > hist_data->n_vals) 5035 seq_puts(m, ","); 5036 5037 if (field->flags & HIST_FIELD_FL_STACKTRACE) 5038 seq_puts(m, "stacktrace"); 5039 else 5040 hist_field_print(m, field); 5041 } 5042 5043 seq_puts(m, ":vals="); 5044 5045 for_each_hist_val_field(i, hist_data) { 5046 field = hist_data->fields[i]; 5047 if (field->flags & HIST_FIELD_FL_VAR) { 5048 have_var = true; 5049 continue; 5050 } 5051 5052 if (i == HITCOUNT_IDX) 5053 seq_puts(m, "hitcount"); 5054 else { 5055 seq_puts(m, ","); 5056 hist_field_print(m, field); 5057 } 5058 } 5059 5060 if (have_var) { 5061 unsigned int n = 0; 5062 5063 seq_puts(m, ":"); 5064 5065 for_each_hist_val_field(i, hist_data) { 5066 field = hist_data->fields[i]; 5067 5068 if (field->flags & HIST_FIELD_FL_VAR) { 5069 if (n++) 5070 seq_puts(m, ","); 5071 hist_field_print(m, field); 5072 } 5073 } 5074 } 5075 5076 seq_puts(m, ":sort="); 5077 5078 for (i = 0; i < hist_data->n_sort_keys; i++) { 5079 struct tracing_map_sort_key *sort_key; 5080 unsigned int idx, first_key_idx; 5081 5082 /* skip VAR vals */ 5083 first_key_idx = hist_data->n_vals - hist_data->n_vars; 5084 5085 sort_key = &hist_data->sort_keys[i]; 5086 idx = sort_key->field_idx; 5087 5088 if (WARN_ON(idx >= HIST_FIELDS_MAX)) 5089 return -EINVAL; 5090 5091 if (i > 0) 5092 seq_puts(m, ","); 5093 5094 if (idx == HITCOUNT_IDX) 5095 seq_puts(m, "hitcount"); 5096 else { 5097 if (idx >= first_key_idx) 5098 idx += hist_data->n_vars; 5099 hist_field_print(m, hist_data->fields[idx]); 5100 } 5101 5102 if (sort_key->descending) 5103 seq_puts(m, ".descending"); 5104 } 5105 seq_printf(m, ":size=%u", (1 << hist_data->map->map_bits)); 5106 if (hist_data->enable_timestamps) 5107 seq_printf(m, ":clock=%s", hist_data->attrs->clock); 5108 5109 print_actions_spec(m, hist_data); 5110 5111 if (data->filter_str) 5112 seq_printf(m, " if %s", data->filter_str); 5113 5114 if (data->paused) 5115 seq_puts(m, " [paused]"); 5116 else 5117 seq_puts(m, " [active]"); 5118 5119 seq_putc(m, '\n'); 5120 5121 return 0; 5122 } 5123 5124 static int event_hist_trigger_init(struct event_trigger_ops *ops, 5125 struct event_trigger_data *data) 5126 { 5127 struct hist_trigger_data *hist_data = data->private_data; 5128 5129 if (!data->ref && hist_data->attrs->name) 5130 save_named_trigger(hist_data->attrs->name, data); 5131 5132 data->ref++; 5133 5134 return 0; 5135 } 5136 5137 static void unregister_field_var_hists(struct hist_trigger_data *hist_data) 5138 { 5139 struct trace_event_file *file; 5140 unsigned int i; 5141 char *cmd; 5142 int ret; 5143 5144 for (i = 0; i < hist_data->n_field_var_hists; i++) { 5145 file = hist_data->field_var_hists[i]->hist_data->event_file; 5146 cmd = hist_data->field_var_hists[i]->cmd; 5147 ret = event_hist_trigger_func(&trigger_hist_cmd, file, 5148 "!hist", "hist", cmd); 5149 } 5150 } 5151 5152 static void event_hist_trigger_free(struct event_trigger_ops *ops, 5153 struct event_trigger_data *data) 5154 { 5155 struct hist_trigger_data *hist_data = data->private_data; 5156 5157 if (WARN_ON_ONCE(data->ref <= 0)) 5158 return; 5159 5160 data->ref--; 5161 if (!data->ref) { 5162 if (data->name) 5163 del_named_trigger(data); 5164 5165 trigger_data_free(data); 5166 5167 remove_hist_vars(hist_data); 5168 5169 unregister_field_var_hists(hist_data); 5170 5171 destroy_hist_data(hist_data); 5172 } 5173 } 5174 5175 static struct event_trigger_ops event_hist_trigger_ops = { 5176 .func = event_hist_trigger, 5177 .print = event_hist_trigger_print, 5178 .init = event_hist_trigger_init, 5179 .free = event_hist_trigger_free, 5180 }; 5181 5182 static int event_hist_trigger_named_init(struct event_trigger_ops *ops, 5183 struct event_trigger_data *data) 5184 { 5185 data->ref++; 5186 5187 save_named_trigger(data->named_data->name, data); 5188 5189 event_hist_trigger_init(ops, data->named_data); 5190 5191 return 0; 5192 } 5193 5194 static void event_hist_trigger_named_free(struct event_trigger_ops *ops, 5195 struct event_trigger_data *data) 5196 { 5197 if (WARN_ON_ONCE(data->ref <= 0)) 5198 return; 5199 5200 event_hist_trigger_free(ops, data->named_data); 5201 5202 data->ref--; 5203 if (!data->ref) { 5204 del_named_trigger(data); 5205 trigger_data_free(data); 5206 } 5207 } 5208 5209 static struct event_trigger_ops event_hist_trigger_named_ops = { 5210 .func = event_hist_trigger, 5211 .print = event_hist_trigger_print, 5212 .init = event_hist_trigger_named_init, 5213 .free = event_hist_trigger_named_free, 5214 }; 5215 5216 static struct event_trigger_ops *event_hist_get_trigger_ops(char *cmd, 5217 char *param) 5218 { 5219 return &event_hist_trigger_ops; 5220 } 5221 5222 static void hist_clear(struct event_trigger_data *data) 5223 { 5224 struct hist_trigger_data *hist_data = data->private_data; 5225 5226 if (data->name) 5227 pause_named_trigger(data); 5228 5229 tracepoint_synchronize_unregister(); 5230 5231 tracing_map_clear(hist_data->map); 5232 5233 if (data->name) 5234 unpause_named_trigger(data); 5235 } 5236 5237 static bool compatible_field(struct ftrace_event_field *field, 5238 struct ftrace_event_field *test_field) 5239 { 5240 if (field == test_field) 5241 return true; 5242 if (field == NULL || test_field == NULL) 5243 return false; 5244 if (strcmp(field->name, test_field->name) != 0) 5245 return false; 5246 if (strcmp(field->type, test_field->type) != 0) 5247 return false; 5248 if (field->size != test_field->size) 5249 return false; 5250 if (field->is_signed != test_field->is_signed) 5251 return false; 5252 5253 return true; 5254 } 5255 5256 static bool hist_trigger_match(struct event_trigger_data *data, 5257 struct event_trigger_data *data_test, 5258 struct event_trigger_data *named_data, 5259 bool ignore_filter) 5260 { 5261 struct tracing_map_sort_key *sort_key, *sort_key_test; 5262 struct hist_trigger_data *hist_data, *hist_data_test; 5263 struct hist_field *key_field, *key_field_test; 5264 unsigned int i; 5265 5266 if (named_data && (named_data != data_test) && 5267 (named_data != data_test->named_data)) 5268 return false; 5269 5270 if (!named_data && is_named_trigger(data_test)) 5271 return false; 5272 5273 hist_data = data->private_data; 5274 hist_data_test = data_test->private_data; 5275 5276 if (hist_data->n_vals != hist_data_test->n_vals || 5277 hist_data->n_fields != hist_data_test->n_fields || 5278 hist_data->n_sort_keys != hist_data_test->n_sort_keys) 5279 return false; 5280 5281 if (!ignore_filter) { 5282 if ((data->filter_str && !data_test->filter_str) || 5283 (!data->filter_str && data_test->filter_str)) 5284 return false; 5285 } 5286 5287 for_each_hist_field(i, hist_data) { 5288 key_field = hist_data->fields[i]; 5289 key_field_test = hist_data_test->fields[i]; 5290 5291 if (key_field->flags != key_field_test->flags) 5292 return false; 5293 if (!compatible_field(key_field->field, key_field_test->field)) 5294 return false; 5295 if (key_field->offset != key_field_test->offset) 5296 return false; 5297 if (key_field->size != key_field_test->size) 5298 return false; 5299 if (key_field->is_signed != key_field_test->is_signed) 5300 return false; 5301 if (!!key_field->var.name != !!key_field_test->var.name) 5302 return false; 5303 if (key_field->var.name && 5304 strcmp(key_field->var.name, key_field_test->var.name) != 0) 5305 return false; 5306 } 5307 5308 for (i = 0; i < hist_data->n_sort_keys; i++) { 5309 sort_key = &hist_data->sort_keys[i]; 5310 sort_key_test = &hist_data_test->sort_keys[i]; 5311 5312 if (sort_key->field_idx != sort_key_test->field_idx || 5313 sort_key->descending != sort_key_test->descending) 5314 return false; 5315 } 5316 5317 if (!ignore_filter && data->filter_str && 5318 (strcmp(data->filter_str, data_test->filter_str) != 0)) 5319 return false; 5320 5321 if (!actions_match(hist_data, hist_data_test)) 5322 return false; 5323 5324 return true; 5325 } 5326 5327 static int hist_register_trigger(char *glob, struct event_trigger_ops *ops, 5328 struct event_trigger_data *data, 5329 struct trace_event_file *file) 5330 { 5331 struct hist_trigger_data *hist_data = data->private_data; 5332 struct event_trigger_data *test, *named_data = NULL; 5333 int ret = 0; 5334 5335 if (hist_data->attrs->name) { 5336 named_data = find_named_trigger(hist_data->attrs->name); 5337 if (named_data) { 5338 if (!hist_trigger_match(data, named_data, named_data, 5339 true)) { 5340 hist_err("Named hist trigger doesn't match existing named trigger (includes variables): ", hist_data->attrs->name); 5341 ret = -EINVAL; 5342 goto out; 5343 } 5344 } 5345 } 5346 5347 if (hist_data->attrs->name && !named_data) 5348 goto new; 5349 5350 list_for_each_entry_rcu(test, &file->triggers, list) { 5351 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 5352 if (!hist_trigger_match(data, test, named_data, false)) 5353 continue; 5354 if (hist_data->attrs->pause) 5355 test->paused = true; 5356 else if (hist_data->attrs->cont) 5357 test->paused = false; 5358 else if (hist_data->attrs->clear) 5359 hist_clear(test); 5360 else { 5361 hist_err("Hist trigger already exists", NULL); 5362 ret = -EEXIST; 5363 } 5364 goto out; 5365 } 5366 } 5367 new: 5368 if (hist_data->attrs->cont || hist_data->attrs->clear) { 5369 hist_err("Can't clear or continue a nonexistent hist trigger", NULL); 5370 ret = -ENOENT; 5371 goto out; 5372 } 5373 5374 if (hist_data->attrs->pause) 5375 data->paused = true; 5376 5377 if (named_data) { 5378 data->private_data = named_data->private_data; 5379 set_named_trigger_data(data, named_data); 5380 data->ops = &event_hist_trigger_named_ops; 5381 } 5382 5383 if (data->ops->init) { 5384 ret = data->ops->init(data->ops, data); 5385 if (ret < 0) 5386 goto out; 5387 } 5388 5389 if (hist_data->enable_timestamps) { 5390 char *clock = hist_data->attrs->clock; 5391 5392 ret = tracing_set_clock(file->tr, hist_data->attrs->clock); 5393 if (ret) { 5394 hist_err("Couldn't set trace_clock: ", clock); 5395 goto out; 5396 } 5397 5398 tracing_set_time_stamp_abs(file->tr, true); 5399 } 5400 5401 if (named_data) 5402 destroy_hist_data(hist_data); 5403 5404 ret++; 5405 out: 5406 return ret; 5407 } 5408 5409 static int hist_trigger_enable(struct event_trigger_data *data, 5410 struct trace_event_file *file) 5411 { 5412 int ret = 0; 5413 5414 list_add_tail_rcu(&data->list, &file->triggers); 5415 5416 update_cond_flag(file); 5417 5418 if (trace_event_trigger_enable_disable(file, 1) < 0) { 5419 list_del_rcu(&data->list); 5420 update_cond_flag(file); 5421 ret--; 5422 } 5423 5424 return ret; 5425 } 5426 5427 static bool have_hist_trigger_match(struct event_trigger_data *data, 5428 struct trace_event_file *file) 5429 { 5430 struct hist_trigger_data *hist_data = data->private_data; 5431 struct event_trigger_data *test, *named_data = NULL; 5432 bool match = false; 5433 5434 if (hist_data->attrs->name) 5435 named_data = find_named_trigger(hist_data->attrs->name); 5436 5437 list_for_each_entry_rcu(test, &file->triggers, list) { 5438 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 5439 if (hist_trigger_match(data, test, named_data, false)) { 5440 match = true; 5441 break; 5442 } 5443 } 5444 } 5445 5446 return match; 5447 } 5448 5449 static bool hist_trigger_check_refs(struct event_trigger_data *data, 5450 struct trace_event_file *file) 5451 { 5452 struct hist_trigger_data *hist_data = data->private_data; 5453 struct event_trigger_data *test, *named_data = NULL; 5454 5455 if (hist_data->attrs->name) 5456 named_data = find_named_trigger(hist_data->attrs->name); 5457 5458 list_for_each_entry_rcu(test, &file->triggers, list) { 5459 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 5460 if (!hist_trigger_match(data, test, named_data, false)) 5461 continue; 5462 hist_data = test->private_data; 5463 if (check_var_refs(hist_data)) 5464 return true; 5465 break; 5466 } 5467 } 5468 5469 return false; 5470 } 5471 5472 static void hist_unregister_trigger(char *glob, struct event_trigger_ops *ops, 5473 struct event_trigger_data *data, 5474 struct trace_event_file *file) 5475 { 5476 struct hist_trigger_data *hist_data = data->private_data; 5477 struct event_trigger_data *test, *named_data = NULL; 5478 bool unregistered = false; 5479 5480 if (hist_data->attrs->name) 5481 named_data = find_named_trigger(hist_data->attrs->name); 5482 5483 list_for_each_entry_rcu(test, &file->triggers, list) { 5484 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 5485 if (!hist_trigger_match(data, test, named_data, false)) 5486 continue; 5487 unregistered = true; 5488 list_del_rcu(&test->list); 5489 trace_event_trigger_enable_disable(file, 0); 5490 update_cond_flag(file); 5491 break; 5492 } 5493 } 5494 5495 if (unregistered && test->ops->free) 5496 test->ops->free(test->ops, test); 5497 5498 if (hist_data->enable_timestamps) { 5499 if (!hist_data->remove || unregistered) 5500 tracing_set_time_stamp_abs(file->tr, false); 5501 } 5502 } 5503 5504 static bool hist_file_check_refs(struct trace_event_file *file) 5505 { 5506 struct hist_trigger_data *hist_data; 5507 struct event_trigger_data *test; 5508 5509 list_for_each_entry_rcu(test, &file->triggers, list) { 5510 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 5511 hist_data = test->private_data; 5512 if (check_var_refs(hist_data)) 5513 return true; 5514 } 5515 } 5516 5517 return false; 5518 } 5519 5520 static void hist_unreg_all(struct trace_event_file *file) 5521 { 5522 struct event_trigger_data *test, *n; 5523 struct hist_trigger_data *hist_data; 5524 struct synth_event *se; 5525 const char *se_name; 5526 5527 lockdep_assert_held(&event_mutex); 5528 5529 if (hist_file_check_refs(file)) 5530 return; 5531 5532 list_for_each_entry_safe(test, n, &file->triggers, list) { 5533 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 5534 hist_data = test->private_data; 5535 list_del_rcu(&test->list); 5536 trace_event_trigger_enable_disable(file, 0); 5537 5538 se_name = trace_event_name(file->event_call); 5539 se = find_synth_event(se_name); 5540 if (se) 5541 se->ref--; 5542 5543 update_cond_flag(file); 5544 if (hist_data->enable_timestamps) 5545 tracing_set_time_stamp_abs(file->tr, false); 5546 if (test->ops->free) 5547 test->ops->free(test->ops, test); 5548 } 5549 } 5550 } 5551 5552 static int event_hist_trigger_func(struct event_command *cmd_ops, 5553 struct trace_event_file *file, 5554 char *glob, char *cmd, char *param) 5555 { 5556 unsigned int hist_trigger_bits = TRACING_MAP_BITS_DEFAULT; 5557 struct event_trigger_data *trigger_data; 5558 struct hist_trigger_attrs *attrs; 5559 struct event_trigger_ops *trigger_ops; 5560 struct hist_trigger_data *hist_data; 5561 struct synth_event *se; 5562 const char *se_name; 5563 bool remove = false; 5564 char *trigger, *p; 5565 int ret = 0; 5566 5567 lockdep_assert_held(&event_mutex); 5568 5569 if (glob && strlen(glob)) { 5570 last_cmd_set(param); 5571 hist_err_clear(); 5572 } 5573 5574 if (!param) 5575 return -EINVAL; 5576 5577 if (glob[0] == '!') 5578 remove = true; 5579 5580 /* 5581 * separate the trigger from the filter (k:v [if filter]) 5582 * allowing for whitespace in the trigger 5583 */ 5584 p = trigger = param; 5585 do { 5586 p = strstr(p, "if"); 5587 if (!p) 5588 break; 5589 if (p == param) 5590 return -EINVAL; 5591 if (*(p - 1) != ' ' && *(p - 1) != '\t') { 5592 p++; 5593 continue; 5594 } 5595 if (p >= param + strlen(param) - (sizeof("if") - 1) - 1) 5596 return -EINVAL; 5597 if (*(p + sizeof("if") - 1) != ' ' && *(p + sizeof("if") - 1) != '\t') { 5598 p++; 5599 continue; 5600 } 5601 break; 5602 } while (p); 5603 5604 if (!p) 5605 param = NULL; 5606 else { 5607 *(p - 1) = '\0'; 5608 param = strstrip(p); 5609 trigger = strstrip(trigger); 5610 } 5611 5612 attrs = parse_hist_trigger_attrs(trigger); 5613 if (IS_ERR(attrs)) 5614 return PTR_ERR(attrs); 5615 5616 if (attrs->map_bits) 5617 hist_trigger_bits = attrs->map_bits; 5618 5619 hist_data = create_hist_data(hist_trigger_bits, attrs, file, remove); 5620 if (IS_ERR(hist_data)) { 5621 destroy_hist_trigger_attrs(attrs); 5622 return PTR_ERR(hist_data); 5623 } 5624 5625 trigger_ops = cmd_ops->get_trigger_ops(cmd, trigger); 5626 5627 trigger_data = kzalloc(sizeof(*trigger_data), GFP_KERNEL); 5628 if (!trigger_data) { 5629 ret = -ENOMEM; 5630 goto out_free; 5631 } 5632 5633 trigger_data->count = -1; 5634 trigger_data->ops = trigger_ops; 5635 trigger_data->cmd_ops = cmd_ops; 5636 5637 INIT_LIST_HEAD(&trigger_data->list); 5638 RCU_INIT_POINTER(trigger_data->filter, NULL); 5639 5640 trigger_data->private_data = hist_data; 5641 5642 /* if param is non-empty, it's supposed to be a filter */ 5643 if (param && cmd_ops->set_filter) { 5644 ret = cmd_ops->set_filter(param, trigger_data, file); 5645 if (ret < 0) 5646 goto out_free; 5647 } 5648 5649 if (remove) { 5650 if (!have_hist_trigger_match(trigger_data, file)) 5651 goto out_free; 5652 5653 if (hist_trigger_check_refs(trigger_data, file)) { 5654 ret = -EBUSY; 5655 goto out_free; 5656 } 5657 5658 cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file); 5659 se_name = trace_event_name(file->event_call); 5660 se = find_synth_event(se_name); 5661 if (se) 5662 se->ref--; 5663 ret = 0; 5664 goto out_free; 5665 } 5666 5667 ret = cmd_ops->reg(glob, trigger_ops, trigger_data, file); 5668 /* 5669 * The above returns on success the # of triggers registered, 5670 * but if it didn't register any it returns zero. Consider no 5671 * triggers registered a failure too. 5672 */ 5673 if (!ret) { 5674 if (!(attrs->pause || attrs->cont || attrs->clear)) 5675 ret = -ENOENT; 5676 goto out_free; 5677 } else if (ret < 0) 5678 goto out_free; 5679 5680 if (get_named_trigger_data(trigger_data)) 5681 goto enable; 5682 5683 if (has_hist_vars(hist_data)) 5684 save_hist_vars(hist_data); 5685 5686 ret = create_actions(hist_data, file); 5687 if (ret) 5688 goto out_unreg; 5689 5690 ret = tracing_map_init(hist_data->map); 5691 if (ret) 5692 goto out_unreg; 5693 enable: 5694 ret = hist_trigger_enable(trigger_data, file); 5695 if (ret) 5696 goto out_unreg; 5697 5698 se_name = trace_event_name(file->event_call); 5699 se = find_synth_event(se_name); 5700 if (se) 5701 se->ref++; 5702 /* Just return zero, not the number of registered triggers */ 5703 ret = 0; 5704 out: 5705 if (ret == 0) 5706 hist_err_clear(); 5707 5708 return ret; 5709 out_unreg: 5710 cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file); 5711 out_free: 5712 if (cmd_ops->set_filter) 5713 cmd_ops->set_filter(NULL, trigger_data, NULL); 5714 5715 remove_hist_vars(hist_data); 5716 5717 kfree(trigger_data); 5718 5719 destroy_hist_data(hist_data); 5720 goto out; 5721 } 5722 5723 static struct event_command trigger_hist_cmd = { 5724 .name = "hist", 5725 .trigger_type = ETT_EVENT_HIST, 5726 .flags = EVENT_CMD_FL_NEEDS_REC, 5727 .func = event_hist_trigger_func, 5728 .reg = hist_register_trigger, 5729 .unreg = hist_unregister_trigger, 5730 .unreg_all = hist_unreg_all, 5731 .get_trigger_ops = event_hist_get_trigger_ops, 5732 .set_filter = set_trigger_filter, 5733 }; 5734 5735 __init int register_trigger_hist_cmd(void) 5736 { 5737 int ret; 5738 5739 ret = register_event_command(&trigger_hist_cmd); 5740 WARN_ON(ret < 0); 5741 5742 return ret; 5743 } 5744 5745 static void 5746 hist_enable_trigger(struct event_trigger_data *data, void *rec, 5747 struct ring_buffer_event *event) 5748 { 5749 struct enable_trigger_data *enable_data = data->private_data; 5750 struct event_trigger_data *test; 5751 5752 list_for_each_entry_rcu(test, &enable_data->file->triggers, list) { 5753 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 5754 if (enable_data->enable) 5755 test->paused = false; 5756 else 5757 test->paused = true; 5758 } 5759 } 5760 } 5761 5762 static void 5763 hist_enable_count_trigger(struct event_trigger_data *data, void *rec, 5764 struct ring_buffer_event *event) 5765 { 5766 if (!data->count) 5767 return; 5768 5769 if (data->count != -1) 5770 (data->count)--; 5771 5772 hist_enable_trigger(data, rec, event); 5773 } 5774 5775 static struct event_trigger_ops hist_enable_trigger_ops = { 5776 .func = hist_enable_trigger, 5777 .print = event_enable_trigger_print, 5778 .init = event_trigger_init, 5779 .free = event_enable_trigger_free, 5780 }; 5781 5782 static struct event_trigger_ops hist_enable_count_trigger_ops = { 5783 .func = hist_enable_count_trigger, 5784 .print = event_enable_trigger_print, 5785 .init = event_trigger_init, 5786 .free = event_enable_trigger_free, 5787 }; 5788 5789 static struct event_trigger_ops hist_disable_trigger_ops = { 5790 .func = hist_enable_trigger, 5791 .print = event_enable_trigger_print, 5792 .init = event_trigger_init, 5793 .free = event_enable_trigger_free, 5794 }; 5795 5796 static struct event_trigger_ops hist_disable_count_trigger_ops = { 5797 .func = hist_enable_count_trigger, 5798 .print = event_enable_trigger_print, 5799 .init = event_trigger_init, 5800 .free = event_enable_trigger_free, 5801 }; 5802 5803 static struct event_trigger_ops * 5804 hist_enable_get_trigger_ops(char *cmd, char *param) 5805 { 5806 struct event_trigger_ops *ops; 5807 bool enable; 5808 5809 enable = (strcmp(cmd, ENABLE_HIST_STR) == 0); 5810 5811 if (enable) 5812 ops = param ? &hist_enable_count_trigger_ops : 5813 &hist_enable_trigger_ops; 5814 else 5815 ops = param ? &hist_disable_count_trigger_ops : 5816 &hist_disable_trigger_ops; 5817 5818 return ops; 5819 } 5820 5821 static void hist_enable_unreg_all(struct trace_event_file *file) 5822 { 5823 struct event_trigger_data *test, *n; 5824 5825 list_for_each_entry_safe(test, n, &file->triggers, list) { 5826 if (test->cmd_ops->trigger_type == ETT_HIST_ENABLE) { 5827 list_del_rcu(&test->list); 5828 update_cond_flag(file); 5829 trace_event_trigger_enable_disable(file, 0); 5830 if (test->ops->free) 5831 test->ops->free(test->ops, test); 5832 } 5833 } 5834 } 5835 5836 static struct event_command trigger_hist_enable_cmd = { 5837 .name = ENABLE_HIST_STR, 5838 .trigger_type = ETT_HIST_ENABLE, 5839 .func = event_enable_trigger_func, 5840 .reg = event_enable_register_trigger, 5841 .unreg = event_enable_unregister_trigger, 5842 .unreg_all = hist_enable_unreg_all, 5843 .get_trigger_ops = hist_enable_get_trigger_ops, 5844 .set_filter = set_trigger_filter, 5845 }; 5846 5847 static struct event_command trigger_hist_disable_cmd = { 5848 .name = DISABLE_HIST_STR, 5849 .trigger_type = ETT_HIST_ENABLE, 5850 .func = event_enable_trigger_func, 5851 .reg = event_enable_register_trigger, 5852 .unreg = event_enable_unregister_trigger, 5853 .unreg_all = hist_enable_unreg_all, 5854 .get_trigger_ops = hist_enable_get_trigger_ops, 5855 .set_filter = set_trigger_filter, 5856 }; 5857 5858 static __init void unregister_trigger_hist_enable_disable_cmds(void) 5859 { 5860 unregister_event_command(&trigger_hist_enable_cmd); 5861 unregister_event_command(&trigger_hist_disable_cmd); 5862 } 5863 5864 __init int register_trigger_hist_enable_disable_cmds(void) 5865 { 5866 int ret; 5867 5868 ret = register_event_command(&trigger_hist_enable_cmd); 5869 if (WARN_ON(ret < 0)) 5870 return ret; 5871 ret = register_event_command(&trigger_hist_disable_cmd); 5872 if (WARN_ON(ret < 0)) 5873 unregister_trigger_hist_enable_disable_cmds(); 5874 5875 return ret; 5876 } 5877 5878 static __init int trace_events_hist_init(void) 5879 { 5880 struct dentry *entry = NULL; 5881 struct dentry *d_tracer; 5882 int err = 0; 5883 5884 err = dyn_event_register(&synth_event_ops); 5885 if (err) { 5886 pr_warn("Could not register synth_event_ops\n"); 5887 return err; 5888 } 5889 5890 d_tracer = tracing_init_dentry(); 5891 if (IS_ERR(d_tracer)) { 5892 err = PTR_ERR(d_tracer); 5893 goto err; 5894 } 5895 5896 entry = tracefs_create_file("synthetic_events", 0644, d_tracer, 5897 NULL, &synth_events_fops); 5898 if (!entry) { 5899 err = -ENODEV; 5900 goto err; 5901 } 5902 5903 return err; 5904 err: 5905 pr_warn("Could not create tracefs 'synthetic_events' entry\n"); 5906 5907 return err; 5908 } 5909 5910 fs_initcall(trace_events_hist_init); 5911