1 #include <trace/syscall.h> 2 #include <trace/events/syscalls.h> 3 #include <linux/syscalls.h> 4 #include <linux/slab.h> 5 #include <linux/kernel.h> 6 #include <linux/module.h> /* for MODULE_NAME_LEN via KSYM_SYMBOL_LEN */ 7 #include <linux/ftrace.h> 8 #include <linux/perf_event.h> 9 #include <asm/syscall.h> 10 11 #include "trace_output.h" 12 #include "trace.h" 13 14 static DEFINE_MUTEX(syscall_trace_lock); 15 16 static int syscall_enter_register(struct ftrace_event_call *event, 17 enum trace_reg type, void *data); 18 static int syscall_exit_register(struct ftrace_event_call *event, 19 enum trace_reg type, void *data); 20 21 static struct list_head * 22 syscall_get_enter_fields(struct ftrace_event_call *call) 23 { 24 struct syscall_metadata *entry = call->data; 25 26 return &entry->enter_fields; 27 } 28 29 extern struct syscall_metadata *__start_syscalls_metadata[]; 30 extern struct syscall_metadata *__stop_syscalls_metadata[]; 31 32 static struct syscall_metadata **syscalls_metadata; 33 34 #ifndef ARCH_HAS_SYSCALL_MATCH_SYM_NAME 35 static inline bool arch_syscall_match_sym_name(const char *sym, const char *name) 36 { 37 /* 38 * Only compare after the "sys" prefix. Archs that use 39 * syscall wrappers may have syscalls symbols aliases prefixed 40 * with ".SyS" or ".sys" instead of "sys", leading to an unwanted 41 * mismatch. 42 */ 43 return !strcmp(sym + 3, name + 3); 44 } 45 #endif 46 47 #ifdef ARCH_TRACE_IGNORE_COMPAT_SYSCALLS 48 /* 49 * Some architectures that allow for 32bit applications 50 * to run on a 64bit kernel, do not map the syscalls for 51 * the 32bit tasks the same as they do for 64bit tasks. 52 * 53 * *cough*x86*cough* 54 * 55 * In such a case, instead of reporting the wrong syscalls, 56 * simply ignore them. 57 * 58 * For an arch to ignore the compat syscalls it needs to 59 * define ARCH_TRACE_IGNORE_COMPAT_SYSCALLS as well as 60 * define the function arch_trace_is_compat_syscall() to let 61 * the tracing system know that it should ignore it. 62 */ 63 static int 64 trace_get_syscall_nr(struct task_struct *task, struct pt_regs *regs) 65 { 66 if (unlikely(arch_trace_is_compat_syscall(regs))) 67 return -1; 68 69 return syscall_get_nr(task, regs); 70 } 71 #else 72 static inline int 73 trace_get_syscall_nr(struct task_struct *task, struct pt_regs *regs) 74 { 75 return syscall_get_nr(task, regs); 76 } 77 #endif /* ARCH_TRACE_IGNORE_COMPAT_SYSCALLS */ 78 79 static __init struct syscall_metadata * 80 find_syscall_meta(unsigned long syscall) 81 { 82 struct syscall_metadata **start; 83 struct syscall_metadata **stop; 84 char str[KSYM_SYMBOL_LEN]; 85 86 87 start = __start_syscalls_metadata; 88 stop = __stop_syscalls_metadata; 89 kallsyms_lookup(syscall, NULL, NULL, NULL, str); 90 91 if (arch_syscall_match_sym_name(str, "sys_ni_syscall")) 92 return NULL; 93 94 for ( ; start < stop; start++) { 95 if ((*start)->name && arch_syscall_match_sym_name(str, (*start)->name)) 96 return *start; 97 } 98 return NULL; 99 } 100 101 static struct syscall_metadata *syscall_nr_to_meta(int nr) 102 { 103 if (!syscalls_metadata || nr >= NR_syscalls || nr < 0) 104 return NULL; 105 106 return syscalls_metadata[nr]; 107 } 108 109 static enum print_line_t 110 print_syscall_enter(struct trace_iterator *iter, int flags, 111 struct trace_event *event) 112 { 113 struct trace_seq *s = &iter->seq; 114 struct trace_entry *ent = iter->ent; 115 struct syscall_trace_enter *trace; 116 struct syscall_metadata *entry; 117 int i, ret, syscall; 118 119 trace = (typeof(trace))ent; 120 syscall = trace->nr; 121 entry = syscall_nr_to_meta(syscall); 122 123 if (!entry) 124 goto end; 125 126 if (entry->enter_event->event.type != ent->type) { 127 WARN_ON_ONCE(1); 128 goto end; 129 } 130 131 ret = trace_seq_printf(s, "%s(", entry->name); 132 if (!ret) 133 return TRACE_TYPE_PARTIAL_LINE; 134 135 for (i = 0; i < entry->nb_args; i++) { 136 /* parameter types */ 137 if (trace_flags & TRACE_ITER_VERBOSE) { 138 ret = trace_seq_printf(s, "%s ", entry->types[i]); 139 if (!ret) 140 return TRACE_TYPE_PARTIAL_LINE; 141 } 142 /* parameter values */ 143 ret = trace_seq_printf(s, "%s: %lx%s", entry->args[i], 144 trace->args[i], 145 i == entry->nb_args - 1 ? "" : ", "); 146 if (!ret) 147 return TRACE_TYPE_PARTIAL_LINE; 148 } 149 150 ret = trace_seq_putc(s, ')'); 151 if (!ret) 152 return TRACE_TYPE_PARTIAL_LINE; 153 154 end: 155 ret = trace_seq_putc(s, '\n'); 156 if (!ret) 157 return TRACE_TYPE_PARTIAL_LINE; 158 159 return TRACE_TYPE_HANDLED; 160 } 161 162 static enum print_line_t 163 print_syscall_exit(struct trace_iterator *iter, int flags, 164 struct trace_event *event) 165 { 166 struct trace_seq *s = &iter->seq; 167 struct trace_entry *ent = iter->ent; 168 struct syscall_trace_exit *trace; 169 int syscall; 170 struct syscall_metadata *entry; 171 int ret; 172 173 trace = (typeof(trace))ent; 174 syscall = trace->nr; 175 entry = syscall_nr_to_meta(syscall); 176 177 if (!entry) { 178 trace_seq_putc(s, '\n'); 179 return TRACE_TYPE_HANDLED; 180 } 181 182 if (entry->exit_event->event.type != ent->type) { 183 WARN_ON_ONCE(1); 184 return TRACE_TYPE_UNHANDLED; 185 } 186 187 ret = trace_seq_printf(s, "%s -> 0x%lx\n", entry->name, 188 trace->ret); 189 if (!ret) 190 return TRACE_TYPE_PARTIAL_LINE; 191 192 return TRACE_TYPE_HANDLED; 193 } 194 195 extern char *__bad_type_size(void); 196 197 #define SYSCALL_FIELD(type, name) \ 198 sizeof(type) != sizeof(trace.name) ? \ 199 __bad_type_size() : \ 200 #type, #name, offsetof(typeof(trace), name), \ 201 sizeof(trace.name), is_signed_type(type) 202 203 static int __init 204 __set_enter_print_fmt(struct syscall_metadata *entry, char *buf, int len) 205 { 206 int i; 207 int pos = 0; 208 209 /* When len=0, we just calculate the needed length */ 210 #define LEN_OR_ZERO (len ? len - pos : 0) 211 212 pos += snprintf(buf + pos, LEN_OR_ZERO, "\""); 213 for (i = 0; i < entry->nb_args; i++) { 214 pos += snprintf(buf + pos, LEN_OR_ZERO, "%s: 0x%%0%zulx%s", 215 entry->args[i], sizeof(unsigned long), 216 i == entry->nb_args - 1 ? "" : ", "); 217 } 218 pos += snprintf(buf + pos, LEN_OR_ZERO, "\""); 219 220 for (i = 0; i < entry->nb_args; i++) { 221 pos += snprintf(buf + pos, LEN_OR_ZERO, 222 ", ((unsigned long)(REC->%s))", entry->args[i]); 223 } 224 225 #undef LEN_OR_ZERO 226 227 /* return the length of print_fmt */ 228 return pos; 229 } 230 231 static int __init set_syscall_print_fmt(struct ftrace_event_call *call) 232 { 233 char *print_fmt; 234 int len; 235 struct syscall_metadata *entry = call->data; 236 237 if (entry->enter_event != call) { 238 call->print_fmt = "\"0x%lx\", REC->ret"; 239 return 0; 240 } 241 242 /* First: called with 0 length to calculate the needed length */ 243 len = __set_enter_print_fmt(entry, NULL, 0); 244 245 print_fmt = kmalloc(len + 1, GFP_KERNEL); 246 if (!print_fmt) 247 return -ENOMEM; 248 249 /* Second: actually write the @print_fmt */ 250 __set_enter_print_fmt(entry, print_fmt, len + 1); 251 call->print_fmt = print_fmt; 252 253 return 0; 254 } 255 256 static void __init free_syscall_print_fmt(struct ftrace_event_call *call) 257 { 258 struct syscall_metadata *entry = call->data; 259 260 if (entry->enter_event == call) 261 kfree(call->print_fmt); 262 } 263 264 static int __init syscall_enter_define_fields(struct ftrace_event_call *call) 265 { 266 struct syscall_trace_enter trace; 267 struct syscall_metadata *meta = call->data; 268 int ret; 269 int i; 270 int offset = offsetof(typeof(trace), args); 271 272 ret = trace_define_field(call, SYSCALL_FIELD(int, nr), FILTER_OTHER); 273 if (ret) 274 return ret; 275 276 for (i = 0; i < meta->nb_args; i++) { 277 ret = trace_define_field(call, meta->types[i], 278 meta->args[i], offset, 279 sizeof(unsigned long), 0, 280 FILTER_OTHER); 281 offset += sizeof(unsigned long); 282 } 283 284 return ret; 285 } 286 287 static int __init syscall_exit_define_fields(struct ftrace_event_call *call) 288 { 289 struct syscall_trace_exit trace; 290 int ret; 291 292 ret = trace_define_field(call, SYSCALL_FIELD(int, nr), FILTER_OTHER); 293 if (ret) 294 return ret; 295 296 ret = trace_define_field(call, SYSCALL_FIELD(long, ret), 297 FILTER_OTHER); 298 299 return ret; 300 } 301 302 static void ftrace_syscall_enter(void *data, struct pt_regs *regs, long id) 303 { 304 struct trace_array *tr = data; 305 struct ftrace_event_file *ftrace_file; 306 struct syscall_trace_enter *entry; 307 struct syscall_metadata *sys_data; 308 struct ring_buffer_event *event; 309 struct ring_buffer *buffer; 310 unsigned long irq_flags; 311 int pc; 312 int syscall_nr; 313 int size; 314 315 syscall_nr = trace_get_syscall_nr(current, regs); 316 if (syscall_nr < 0) 317 return; 318 319 /* Here we're inside tp handler's rcu_read_lock_sched (__DO_TRACE) */ 320 ftrace_file = rcu_dereference_sched(tr->enter_syscall_files[syscall_nr]); 321 if (!ftrace_file) 322 return; 323 324 if (ftrace_trigger_soft_disabled(ftrace_file)) 325 return; 326 327 sys_data = syscall_nr_to_meta(syscall_nr); 328 if (!sys_data) 329 return; 330 331 size = sizeof(*entry) + sizeof(unsigned long) * sys_data->nb_args; 332 333 local_save_flags(irq_flags); 334 pc = preempt_count(); 335 336 buffer = tr->trace_buffer.buffer; 337 event = trace_buffer_lock_reserve(buffer, 338 sys_data->enter_event->event.type, size, irq_flags, pc); 339 if (!event) 340 return; 341 342 entry = ring_buffer_event_data(event); 343 entry->nr = syscall_nr; 344 syscall_get_arguments(current, regs, 0, sys_data->nb_args, entry->args); 345 346 event_trigger_unlock_commit(ftrace_file, buffer, event, entry, 347 irq_flags, pc); 348 } 349 350 static void ftrace_syscall_exit(void *data, struct pt_regs *regs, long ret) 351 { 352 struct trace_array *tr = data; 353 struct ftrace_event_file *ftrace_file; 354 struct syscall_trace_exit *entry; 355 struct syscall_metadata *sys_data; 356 struct ring_buffer_event *event; 357 struct ring_buffer *buffer; 358 unsigned long irq_flags; 359 int pc; 360 int syscall_nr; 361 362 syscall_nr = trace_get_syscall_nr(current, regs); 363 if (syscall_nr < 0) 364 return; 365 366 /* Here we're inside tp handler's rcu_read_lock_sched (__DO_TRACE()) */ 367 ftrace_file = rcu_dereference_sched(tr->exit_syscall_files[syscall_nr]); 368 if (!ftrace_file) 369 return; 370 371 if (ftrace_trigger_soft_disabled(ftrace_file)) 372 return; 373 374 sys_data = syscall_nr_to_meta(syscall_nr); 375 if (!sys_data) 376 return; 377 378 local_save_flags(irq_flags); 379 pc = preempt_count(); 380 381 buffer = tr->trace_buffer.buffer; 382 event = trace_buffer_lock_reserve(buffer, 383 sys_data->exit_event->event.type, sizeof(*entry), 384 irq_flags, pc); 385 if (!event) 386 return; 387 388 entry = ring_buffer_event_data(event); 389 entry->nr = syscall_nr; 390 entry->ret = syscall_get_return_value(current, regs); 391 392 event_trigger_unlock_commit(ftrace_file, buffer, event, entry, 393 irq_flags, pc); 394 } 395 396 static int reg_event_syscall_enter(struct ftrace_event_file *file, 397 struct ftrace_event_call *call) 398 { 399 struct trace_array *tr = file->tr; 400 int ret = 0; 401 int num; 402 403 num = ((struct syscall_metadata *)call->data)->syscall_nr; 404 if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls)) 405 return -ENOSYS; 406 mutex_lock(&syscall_trace_lock); 407 if (!tr->sys_refcount_enter) 408 ret = register_trace_sys_enter(ftrace_syscall_enter, tr); 409 if (!ret) { 410 rcu_assign_pointer(tr->enter_syscall_files[num], file); 411 tr->sys_refcount_enter++; 412 } 413 mutex_unlock(&syscall_trace_lock); 414 return ret; 415 } 416 417 static void unreg_event_syscall_enter(struct ftrace_event_file *file, 418 struct ftrace_event_call *call) 419 { 420 struct trace_array *tr = file->tr; 421 int num; 422 423 num = ((struct syscall_metadata *)call->data)->syscall_nr; 424 if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls)) 425 return; 426 mutex_lock(&syscall_trace_lock); 427 tr->sys_refcount_enter--; 428 rcu_assign_pointer(tr->enter_syscall_files[num], NULL); 429 if (!tr->sys_refcount_enter) 430 unregister_trace_sys_enter(ftrace_syscall_enter, tr); 431 mutex_unlock(&syscall_trace_lock); 432 } 433 434 static int reg_event_syscall_exit(struct ftrace_event_file *file, 435 struct ftrace_event_call *call) 436 { 437 struct trace_array *tr = file->tr; 438 int ret = 0; 439 int num; 440 441 num = ((struct syscall_metadata *)call->data)->syscall_nr; 442 if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls)) 443 return -ENOSYS; 444 mutex_lock(&syscall_trace_lock); 445 if (!tr->sys_refcount_exit) 446 ret = register_trace_sys_exit(ftrace_syscall_exit, tr); 447 if (!ret) { 448 rcu_assign_pointer(tr->exit_syscall_files[num], file); 449 tr->sys_refcount_exit++; 450 } 451 mutex_unlock(&syscall_trace_lock); 452 return ret; 453 } 454 455 static void unreg_event_syscall_exit(struct ftrace_event_file *file, 456 struct ftrace_event_call *call) 457 { 458 struct trace_array *tr = file->tr; 459 int num; 460 461 num = ((struct syscall_metadata *)call->data)->syscall_nr; 462 if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls)) 463 return; 464 mutex_lock(&syscall_trace_lock); 465 tr->sys_refcount_exit--; 466 rcu_assign_pointer(tr->exit_syscall_files[num], NULL); 467 if (!tr->sys_refcount_exit) 468 unregister_trace_sys_exit(ftrace_syscall_exit, tr); 469 mutex_unlock(&syscall_trace_lock); 470 } 471 472 static int __init init_syscall_trace(struct ftrace_event_call *call) 473 { 474 int id; 475 int num; 476 477 num = ((struct syscall_metadata *)call->data)->syscall_nr; 478 if (num < 0 || num >= NR_syscalls) { 479 pr_debug("syscall %s metadata not mapped, disabling ftrace event\n", 480 ((struct syscall_metadata *)call->data)->name); 481 return -ENOSYS; 482 } 483 484 if (set_syscall_print_fmt(call) < 0) 485 return -ENOMEM; 486 487 id = trace_event_raw_init(call); 488 489 if (id < 0) { 490 free_syscall_print_fmt(call); 491 return id; 492 } 493 494 return id; 495 } 496 497 struct trace_event_functions enter_syscall_print_funcs = { 498 .trace = print_syscall_enter, 499 }; 500 501 struct trace_event_functions exit_syscall_print_funcs = { 502 .trace = print_syscall_exit, 503 }; 504 505 struct ftrace_event_class __refdata event_class_syscall_enter = { 506 .system = "syscalls", 507 .reg = syscall_enter_register, 508 .define_fields = syscall_enter_define_fields, 509 .get_fields = syscall_get_enter_fields, 510 .raw_init = init_syscall_trace, 511 }; 512 513 struct ftrace_event_class __refdata event_class_syscall_exit = { 514 .system = "syscalls", 515 .reg = syscall_exit_register, 516 .define_fields = syscall_exit_define_fields, 517 .fields = LIST_HEAD_INIT(event_class_syscall_exit.fields), 518 .raw_init = init_syscall_trace, 519 }; 520 521 unsigned long __init __weak arch_syscall_addr(int nr) 522 { 523 return (unsigned long)sys_call_table[nr]; 524 } 525 526 static int __init init_ftrace_syscalls(void) 527 { 528 struct syscall_metadata *meta; 529 unsigned long addr; 530 int i; 531 532 syscalls_metadata = kcalloc(NR_syscalls, sizeof(*syscalls_metadata), 533 GFP_KERNEL); 534 if (!syscalls_metadata) { 535 WARN_ON(1); 536 return -ENOMEM; 537 } 538 539 for (i = 0; i < NR_syscalls; i++) { 540 addr = arch_syscall_addr(i); 541 meta = find_syscall_meta(addr); 542 if (!meta) 543 continue; 544 545 meta->syscall_nr = i; 546 syscalls_metadata[i] = meta; 547 } 548 549 return 0; 550 } 551 early_initcall(init_ftrace_syscalls); 552 553 #ifdef CONFIG_PERF_EVENTS 554 555 static DECLARE_BITMAP(enabled_perf_enter_syscalls, NR_syscalls); 556 static DECLARE_BITMAP(enabled_perf_exit_syscalls, NR_syscalls); 557 static int sys_perf_refcount_enter; 558 static int sys_perf_refcount_exit; 559 560 static void perf_syscall_enter(void *ignore, struct pt_regs *regs, long id) 561 { 562 struct syscall_metadata *sys_data; 563 struct syscall_trace_enter *rec; 564 struct hlist_head *head; 565 int syscall_nr; 566 int rctx; 567 int size; 568 569 syscall_nr = trace_get_syscall_nr(current, regs); 570 if (syscall_nr < 0) 571 return; 572 if (!test_bit(syscall_nr, enabled_perf_enter_syscalls)) 573 return; 574 575 sys_data = syscall_nr_to_meta(syscall_nr); 576 if (!sys_data) 577 return; 578 579 head = this_cpu_ptr(sys_data->enter_event->perf_events); 580 if (hlist_empty(head)) 581 return; 582 583 /* get the size after alignment with the u32 buffer size field */ 584 size = sizeof(unsigned long) * sys_data->nb_args + sizeof(*rec); 585 size = ALIGN(size + sizeof(u32), sizeof(u64)); 586 size -= sizeof(u32); 587 588 rec = (struct syscall_trace_enter *)perf_trace_buf_prepare(size, 589 sys_data->enter_event->event.type, regs, &rctx); 590 if (!rec) 591 return; 592 593 rec->nr = syscall_nr; 594 syscall_get_arguments(current, regs, 0, sys_data->nb_args, 595 (unsigned long *)&rec->args); 596 perf_trace_buf_submit(rec, size, rctx, 0, 1, regs, head, NULL); 597 } 598 599 static int perf_sysenter_enable(struct ftrace_event_call *call) 600 { 601 int ret = 0; 602 int num; 603 604 num = ((struct syscall_metadata *)call->data)->syscall_nr; 605 606 mutex_lock(&syscall_trace_lock); 607 if (!sys_perf_refcount_enter) 608 ret = register_trace_sys_enter(perf_syscall_enter, NULL); 609 if (ret) { 610 pr_info("event trace: Could not activate" 611 "syscall entry trace point"); 612 } else { 613 set_bit(num, enabled_perf_enter_syscalls); 614 sys_perf_refcount_enter++; 615 } 616 mutex_unlock(&syscall_trace_lock); 617 return ret; 618 } 619 620 static void perf_sysenter_disable(struct ftrace_event_call *call) 621 { 622 int num; 623 624 num = ((struct syscall_metadata *)call->data)->syscall_nr; 625 626 mutex_lock(&syscall_trace_lock); 627 sys_perf_refcount_enter--; 628 clear_bit(num, enabled_perf_enter_syscalls); 629 if (!sys_perf_refcount_enter) 630 unregister_trace_sys_enter(perf_syscall_enter, NULL); 631 mutex_unlock(&syscall_trace_lock); 632 } 633 634 static void perf_syscall_exit(void *ignore, struct pt_regs *regs, long ret) 635 { 636 struct syscall_metadata *sys_data; 637 struct syscall_trace_exit *rec; 638 struct hlist_head *head; 639 int syscall_nr; 640 int rctx; 641 int size; 642 643 syscall_nr = trace_get_syscall_nr(current, regs); 644 if (syscall_nr < 0) 645 return; 646 if (!test_bit(syscall_nr, enabled_perf_exit_syscalls)) 647 return; 648 649 sys_data = syscall_nr_to_meta(syscall_nr); 650 if (!sys_data) 651 return; 652 653 head = this_cpu_ptr(sys_data->exit_event->perf_events); 654 if (hlist_empty(head)) 655 return; 656 657 /* We can probably do that at build time */ 658 size = ALIGN(sizeof(*rec) + sizeof(u32), sizeof(u64)); 659 size -= sizeof(u32); 660 661 rec = (struct syscall_trace_exit *)perf_trace_buf_prepare(size, 662 sys_data->exit_event->event.type, regs, &rctx); 663 if (!rec) 664 return; 665 666 rec->nr = syscall_nr; 667 rec->ret = syscall_get_return_value(current, regs); 668 perf_trace_buf_submit(rec, size, rctx, 0, 1, regs, head, NULL); 669 } 670 671 static int perf_sysexit_enable(struct ftrace_event_call *call) 672 { 673 int ret = 0; 674 int num; 675 676 num = ((struct syscall_metadata *)call->data)->syscall_nr; 677 678 mutex_lock(&syscall_trace_lock); 679 if (!sys_perf_refcount_exit) 680 ret = register_trace_sys_exit(perf_syscall_exit, NULL); 681 if (ret) { 682 pr_info("event trace: Could not activate" 683 "syscall exit trace point"); 684 } else { 685 set_bit(num, enabled_perf_exit_syscalls); 686 sys_perf_refcount_exit++; 687 } 688 mutex_unlock(&syscall_trace_lock); 689 return ret; 690 } 691 692 static void perf_sysexit_disable(struct ftrace_event_call *call) 693 { 694 int num; 695 696 num = ((struct syscall_metadata *)call->data)->syscall_nr; 697 698 mutex_lock(&syscall_trace_lock); 699 sys_perf_refcount_exit--; 700 clear_bit(num, enabled_perf_exit_syscalls); 701 if (!sys_perf_refcount_exit) 702 unregister_trace_sys_exit(perf_syscall_exit, NULL); 703 mutex_unlock(&syscall_trace_lock); 704 } 705 706 #endif /* CONFIG_PERF_EVENTS */ 707 708 static int syscall_enter_register(struct ftrace_event_call *event, 709 enum trace_reg type, void *data) 710 { 711 struct ftrace_event_file *file = data; 712 713 switch (type) { 714 case TRACE_REG_REGISTER: 715 return reg_event_syscall_enter(file, event); 716 case TRACE_REG_UNREGISTER: 717 unreg_event_syscall_enter(file, event); 718 return 0; 719 720 #ifdef CONFIG_PERF_EVENTS 721 case TRACE_REG_PERF_REGISTER: 722 return perf_sysenter_enable(event); 723 case TRACE_REG_PERF_UNREGISTER: 724 perf_sysenter_disable(event); 725 return 0; 726 case TRACE_REG_PERF_OPEN: 727 case TRACE_REG_PERF_CLOSE: 728 case TRACE_REG_PERF_ADD: 729 case TRACE_REG_PERF_DEL: 730 return 0; 731 #endif 732 } 733 return 0; 734 } 735 736 static int syscall_exit_register(struct ftrace_event_call *event, 737 enum trace_reg type, void *data) 738 { 739 struct ftrace_event_file *file = data; 740 741 switch (type) { 742 case TRACE_REG_REGISTER: 743 return reg_event_syscall_exit(file, event); 744 case TRACE_REG_UNREGISTER: 745 unreg_event_syscall_exit(file, event); 746 return 0; 747 748 #ifdef CONFIG_PERF_EVENTS 749 case TRACE_REG_PERF_REGISTER: 750 return perf_sysexit_enable(event); 751 case TRACE_REG_PERF_UNREGISTER: 752 perf_sysexit_disable(event); 753 return 0; 754 case TRACE_REG_PERF_OPEN: 755 case TRACE_REG_PERF_CLOSE: 756 case TRACE_REG_PERF_ADD: 757 case TRACE_REG_PERF_DEL: 758 return 0; 759 #endif 760 } 761 return 0; 762 } 763