1 #ifndef _LINUX_KERNEL_TRACE_H 2 #define _LINUX_KERNEL_TRACE_H 3 4 #include <linux/fs.h> 5 #include <asm/atomic.h> 6 #include <linux/sched.h> 7 #include <linux/clocksource.h> 8 #include <linux/ring_buffer.h> 9 #include <linux/mmiotrace.h> 10 #include <linux/ftrace.h> 11 #include <trace/boot.h> 12 #include <linux/kmemtrace.h> 13 #include <trace/power.h> 14 15 #include <linux/trace_seq.h> 16 #include <linux/ftrace_event.h> 17 18 enum trace_type { 19 __TRACE_FIRST_TYPE = 0, 20 21 TRACE_FN, 22 TRACE_CTX, 23 TRACE_WAKE, 24 TRACE_STACK, 25 TRACE_PRINT, 26 TRACE_BPRINT, 27 TRACE_SPECIAL, 28 TRACE_MMIO_RW, 29 TRACE_MMIO_MAP, 30 TRACE_BRANCH, 31 TRACE_BOOT_CALL, 32 TRACE_BOOT_RET, 33 TRACE_GRAPH_RET, 34 TRACE_GRAPH_ENT, 35 TRACE_USER_STACK, 36 TRACE_HW_BRANCHES, 37 TRACE_KMEM_ALLOC, 38 TRACE_KMEM_FREE, 39 TRACE_POWER, 40 TRACE_BLK, 41 42 __TRACE_LAST_TYPE, 43 }; 44 45 /* 46 * Function trace entry - function address and parent function addres: 47 */ 48 struct ftrace_entry { 49 struct trace_entry ent; 50 unsigned long ip; 51 unsigned long parent_ip; 52 }; 53 54 /* Function call entry */ 55 struct ftrace_graph_ent_entry { 56 struct trace_entry ent; 57 struct ftrace_graph_ent graph_ent; 58 }; 59 60 /* Function return entry */ 61 struct ftrace_graph_ret_entry { 62 struct trace_entry ent; 63 struct ftrace_graph_ret ret; 64 }; 65 extern struct tracer boot_tracer; 66 67 /* 68 * Context switch trace entry - which task (and prio) we switched from/to: 69 */ 70 struct ctx_switch_entry { 71 struct trace_entry ent; 72 unsigned int prev_pid; 73 unsigned char prev_prio; 74 unsigned char prev_state; 75 unsigned int next_pid; 76 unsigned char next_prio; 77 unsigned char next_state; 78 unsigned int next_cpu; 79 }; 80 81 /* 82 * Special (free-form) trace entry: 83 */ 84 struct special_entry { 85 struct trace_entry ent; 86 unsigned long arg1; 87 unsigned long arg2; 88 unsigned long arg3; 89 }; 90 91 /* 92 * Stack-trace entry: 93 */ 94 95 #define FTRACE_STACK_ENTRIES 8 96 97 struct stack_entry { 98 struct trace_entry ent; 99 unsigned long caller[FTRACE_STACK_ENTRIES]; 100 }; 101 102 struct userstack_entry { 103 struct trace_entry ent; 104 unsigned long caller[FTRACE_STACK_ENTRIES]; 105 }; 106 107 /* 108 * trace_printk entry: 109 */ 110 struct bprint_entry { 111 struct trace_entry ent; 112 unsigned long ip; 113 const char *fmt; 114 u32 buf[]; 115 }; 116 117 struct print_entry { 118 struct trace_entry ent; 119 unsigned long ip; 120 char buf[]; 121 }; 122 123 #define TRACE_OLD_SIZE 88 124 125 struct trace_field_cont { 126 unsigned char type; 127 /* Temporary till we get rid of this completely */ 128 char buf[TRACE_OLD_SIZE - 1]; 129 }; 130 131 struct trace_mmiotrace_rw { 132 struct trace_entry ent; 133 struct mmiotrace_rw rw; 134 }; 135 136 struct trace_mmiotrace_map { 137 struct trace_entry ent; 138 struct mmiotrace_map map; 139 }; 140 141 struct trace_boot_call { 142 struct trace_entry ent; 143 struct boot_trace_call boot_call; 144 }; 145 146 struct trace_boot_ret { 147 struct trace_entry ent; 148 struct boot_trace_ret boot_ret; 149 }; 150 151 #define TRACE_FUNC_SIZE 30 152 #define TRACE_FILE_SIZE 20 153 struct trace_branch { 154 struct trace_entry ent; 155 unsigned line; 156 char func[TRACE_FUNC_SIZE+1]; 157 char file[TRACE_FILE_SIZE+1]; 158 char correct; 159 }; 160 161 struct hw_branch_entry { 162 struct trace_entry ent; 163 u64 from; 164 u64 to; 165 }; 166 167 struct trace_power { 168 struct trace_entry ent; 169 struct power_trace state_data; 170 }; 171 172 enum kmemtrace_type_id { 173 KMEMTRACE_TYPE_KMALLOC = 0, /* kmalloc() or kfree(). */ 174 KMEMTRACE_TYPE_CACHE, /* kmem_cache_*(). */ 175 KMEMTRACE_TYPE_PAGES, /* __get_free_pages() and friends. */ 176 }; 177 178 struct kmemtrace_alloc_entry { 179 struct trace_entry ent; 180 enum kmemtrace_type_id type_id; 181 unsigned long call_site; 182 const void *ptr; 183 size_t bytes_req; 184 size_t bytes_alloc; 185 gfp_t gfp_flags; 186 int node; 187 }; 188 189 struct kmemtrace_free_entry { 190 struct trace_entry ent; 191 enum kmemtrace_type_id type_id; 192 unsigned long call_site; 193 const void *ptr; 194 }; 195 196 struct syscall_trace_enter { 197 struct trace_entry ent; 198 int nr; 199 unsigned long args[]; 200 }; 201 202 struct syscall_trace_exit { 203 struct trace_entry ent; 204 int nr; 205 unsigned long ret; 206 }; 207 208 209 /* 210 * trace_flag_type is an enumeration that holds different 211 * states when a trace occurs. These are: 212 * IRQS_OFF - interrupts were disabled 213 * IRQS_NOSUPPORT - arch does not support irqs_disabled_flags 214 * NEED_RESCED - reschedule is requested 215 * HARDIRQ - inside an interrupt handler 216 * SOFTIRQ - inside a softirq handler 217 */ 218 enum trace_flag_type { 219 TRACE_FLAG_IRQS_OFF = 0x01, 220 TRACE_FLAG_IRQS_NOSUPPORT = 0x02, 221 TRACE_FLAG_NEED_RESCHED = 0x04, 222 TRACE_FLAG_HARDIRQ = 0x08, 223 TRACE_FLAG_SOFTIRQ = 0x10, 224 }; 225 226 #define TRACE_BUF_SIZE 1024 227 228 /* 229 * The CPU trace array - it consists of thousands of trace entries 230 * plus some other descriptor data: (for example which task started 231 * the trace, etc.) 232 */ 233 struct trace_array_cpu { 234 atomic_t disabled; 235 void *buffer_page; /* ring buffer spare */ 236 237 unsigned long saved_latency; 238 unsigned long critical_start; 239 unsigned long critical_end; 240 unsigned long critical_sequence; 241 unsigned long nice; 242 unsigned long policy; 243 unsigned long rt_priority; 244 unsigned long skipped_entries; 245 cycle_t preempt_timestamp; 246 pid_t pid; 247 uid_t uid; 248 char comm[TASK_COMM_LEN]; 249 }; 250 251 /* 252 * The trace array - an array of per-CPU trace arrays. This is the 253 * highest level data structure that individual tracers deal with. 254 * They have on/off state as well: 255 */ 256 struct trace_array { 257 struct ring_buffer *buffer; 258 unsigned long entries; 259 int cpu; 260 cycle_t time_start; 261 struct task_struct *waiter; 262 struct trace_array_cpu *data[NR_CPUS]; 263 }; 264 265 #define FTRACE_CMP_TYPE(var, type) \ 266 __builtin_types_compatible_p(typeof(var), type *) 267 268 #undef IF_ASSIGN 269 #define IF_ASSIGN(var, entry, etype, id) \ 270 if (FTRACE_CMP_TYPE(var, etype)) { \ 271 var = (typeof(var))(entry); \ 272 WARN_ON(id && (entry)->type != id); \ 273 break; \ 274 } 275 276 /* Will cause compile errors if type is not found. */ 277 extern void __ftrace_bad_type(void); 278 279 /* 280 * The trace_assign_type is a verifier that the entry type is 281 * the same as the type being assigned. To add new types simply 282 * add a line with the following format: 283 * 284 * IF_ASSIGN(var, ent, type, id); 285 * 286 * Where "type" is the trace type that includes the trace_entry 287 * as the "ent" item. And "id" is the trace identifier that is 288 * used in the trace_type enum. 289 * 290 * If the type can have more than one id, then use zero. 291 */ 292 #define trace_assign_type(var, ent) \ 293 do { \ 294 IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN); \ 295 IF_ASSIGN(var, ent, struct ctx_switch_entry, 0); \ 296 IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK); \ 297 IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\ 298 IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT); \ 299 IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT); \ 300 IF_ASSIGN(var, ent, struct special_entry, 0); \ 301 IF_ASSIGN(var, ent, struct trace_mmiotrace_rw, \ 302 TRACE_MMIO_RW); \ 303 IF_ASSIGN(var, ent, struct trace_mmiotrace_map, \ 304 TRACE_MMIO_MAP); \ 305 IF_ASSIGN(var, ent, struct trace_boot_call, TRACE_BOOT_CALL);\ 306 IF_ASSIGN(var, ent, struct trace_boot_ret, TRACE_BOOT_RET);\ 307 IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \ 308 IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry, \ 309 TRACE_GRAPH_ENT); \ 310 IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry, \ 311 TRACE_GRAPH_RET); \ 312 IF_ASSIGN(var, ent, struct hw_branch_entry, TRACE_HW_BRANCHES);\ 313 IF_ASSIGN(var, ent, struct trace_power, TRACE_POWER); \ 314 IF_ASSIGN(var, ent, struct kmemtrace_alloc_entry, \ 315 TRACE_KMEM_ALLOC); \ 316 IF_ASSIGN(var, ent, struct kmemtrace_free_entry, \ 317 TRACE_KMEM_FREE); \ 318 __ftrace_bad_type(); \ 319 } while (0) 320 321 /* 322 * An option specific to a tracer. This is a boolean value. 323 * The bit is the bit index that sets its value on the 324 * flags value in struct tracer_flags. 325 */ 326 struct tracer_opt { 327 const char *name; /* Will appear on the trace_options file */ 328 u32 bit; /* Mask assigned in val field in tracer_flags */ 329 }; 330 331 /* 332 * The set of specific options for a tracer. Your tracer 333 * have to set the initial value of the flags val. 334 */ 335 struct tracer_flags { 336 u32 val; 337 struct tracer_opt *opts; 338 }; 339 340 /* Makes more easy to define a tracer opt */ 341 #define TRACER_OPT(s, b) .name = #s, .bit = b 342 343 344 /** 345 * struct tracer - a specific tracer and its callbacks to interact with debugfs 346 * @name: the name chosen to select it on the available_tracers file 347 * @init: called when one switches to this tracer (echo name > current_tracer) 348 * @reset: called when one switches to another tracer 349 * @start: called when tracing is unpaused (echo 1 > tracing_enabled) 350 * @stop: called when tracing is paused (echo 0 > tracing_enabled) 351 * @open: called when the trace file is opened 352 * @pipe_open: called when the trace_pipe file is opened 353 * @wait_pipe: override how the user waits for traces on trace_pipe 354 * @close: called when the trace file is released 355 * @read: override the default read callback on trace_pipe 356 * @splice_read: override the default splice_read callback on trace_pipe 357 * @selftest: selftest to run on boot (see trace_selftest.c) 358 * @print_headers: override the first lines that describe your columns 359 * @print_line: callback that prints a trace 360 * @set_flag: signals one of your private flags changed (trace_options file) 361 * @flags: your private flags 362 */ 363 struct tracer { 364 const char *name; 365 int (*init)(struct trace_array *tr); 366 void (*reset)(struct trace_array *tr); 367 void (*start)(struct trace_array *tr); 368 void (*stop)(struct trace_array *tr); 369 void (*open)(struct trace_iterator *iter); 370 void (*pipe_open)(struct trace_iterator *iter); 371 void (*wait_pipe)(struct trace_iterator *iter); 372 void (*close)(struct trace_iterator *iter); 373 ssize_t (*read)(struct trace_iterator *iter, 374 struct file *filp, char __user *ubuf, 375 size_t cnt, loff_t *ppos); 376 ssize_t (*splice_read)(struct trace_iterator *iter, 377 struct file *filp, 378 loff_t *ppos, 379 struct pipe_inode_info *pipe, 380 size_t len, 381 unsigned int flags); 382 #ifdef CONFIG_FTRACE_STARTUP_TEST 383 int (*selftest)(struct tracer *trace, 384 struct trace_array *tr); 385 #endif 386 void (*print_header)(struct seq_file *m); 387 enum print_line_t (*print_line)(struct trace_iterator *iter); 388 /* If you handled the flag setting, return 0 */ 389 int (*set_flag)(u32 old_flags, u32 bit, int set); 390 struct tracer *next; 391 int print_max; 392 struct tracer_flags *flags; 393 struct tracer_stat *stats; 394 }; 395 396 397 #define TRACE_PIPE_ALL_CPU -1 398 399 int tracer_init(struct tracer *t, struct trace_array *tr); 400 int tracing_is_enabled(void); 401 void trace_wake_up(void); 402 void tracing_reset(struct trace_array *tr, int cpu); 403 void tracing_reset_online_cpus(struct trace_array *tr); 404 void tracing_reset_current(int cpu); 405 void tracing_reset_current_online_cpus(void); 406 int tracing_open_generic(struct inode *inode, struct file *filp); 407 struct dentry *trace_create_file(const char *name, 408 mode_t mode, 409 struct dentry *parent, 410 void *data, 411 const struct file_operations *fops); 412 413 struct dentry *tracing_init_dentry(void); 414 void init_tracer_sysprof_debugfs(struct dentry *d_tracer); 415 416 struct ring_buffer_event; 417 418 struct ring_buffer_event * 419 trace_buffer_lock_reserve(struct ring_buffer *buffer, 420 int type, 421 unsigned long len, 422 unsigned long flags, 423 int pc); 424 void trace_buffer_unlock_commit(struct ring_buffer *buffer, 425 struct ring_buffer_event *event, 426 unsigned long flags, int pc); 427 428 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr, 429 struct trace_array_cpu *data); 430 431 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, 432 int *ent_cpu, u64 *ent_ts); 433 434 void default_wait_pipe(struct trace_iterator *iter); 435 void poll_wait_pipe(struct trace_iterator *iter); 436 437 void ftrace(struct trace_array *tr, 438 struct trace_array_cpu *data, 439 unsigned long ip, 440 unsigned long parent_ip, 441 unsigned long flags, int pc); 442 void tracing_sched_switch_trace(struct trace_array *tr, 443 struct task_struct *prev, 444 struct task_struct *next, 445 unsigned long flags, int pc); 446 447 void tracing_sched_wakeup_trace(struct trace_array *tr, 448 struct task_struct *wakee, 449 struct task_struct *cur, 450 unsigned long flags, int pc); 451 void trace_special(struct trace_array *tr, 452 struct trace_array_cpu *data, 453 unsigned long arg1, 454 unsigned long arg2, 455 unsigned long arg3, int pc); 456 void trace_function(struct trace_array *tr, 457 unsigned long ip, 458 unsigned long parent_ip, 459 unsigned long flags, int pc); 460 461 void trace_graph_return(struct ftrace_graph_ret *trace); 462 int trace_graph_entry(struct ftrace_graph_ent *trace); 463 void set_graph_array(struct trace_array *tr); 464 465 void tracing_start_cmdline_record(void); 466 void tracing_stop_cmdline_record(void); 467 void tracing_sched_switch_assign_trace(struct trace_array *tr); 468 void tracing_stop_sched_switch_record(void); 469 void tracing_start_sched_switch_record(void); 470 int register_tracer(struct tracer *type); 471 void unregister_tracer(struct tracer *type); 472 473 extern unsigned long nsecs_to_usecs(unsigned long nsecs); 474 475 #ifdef CONFIG_TRACER_MAX_TRACE 476 extern unsigned long tracing_max_latency; 477 extern unsigned long tracing_thresh; 478 479 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu); 480 void update_max_tr_single(struct trace_array *tr, 481 struct task_struct *tsk, int cpu); 482 #endif /* CONFIG_TRACER_MAX_TRACE */ 483 484 #ifdef CONFIG_STACKTRACE 485 void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags, 486 int skip, int pc); 487 488 void ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, 489 int pc); 490 491 void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, 492 int pc); 493 #else 494 static inline void ftrace_trace_stack(struct trace_array *tr, 495 unsigned long flags, int skip, int pc) 496 { 497 } 498 499 static inline void ftrace_trace_userstack(struct trace_array *tr, 500 unsigned long flags, int pc) 501 { 502 } 503 504 static inline void __trace_stack(struct trace_array *tr, unsigned long flags, 505 int skip, int pc) 506 { 507 } 508 #endif /* CONFIG_STACKTRACE */ 509 510 extern cycle_t ftrace_now(int cpu); 511 512 #ifdef CONFIG_CONTEXT_SWITCH_TRACER 513 typedef void 514 (*tracer_switch_func_t)(void *private, 515 void *__rq, 516 struct task_struct *prev, 517 struct task_struct *next); 518 519 struct tracer_switch_ops { 520 tracer_switch_func_t func; 521 void *private; 522 struct tracer_switch_ops *next; 523 }; 524 #endif /* CONFIG_CONTEXT_SWITCH_TRACER */ 525 526 extern void trace_find_cmdline(int pid, char comm[]); 527 528 #ifdef CONFIG_DYNAMIC_FTRACE 529 extern unsigned long ftrace_update_tot_cnt; 530 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func 531 extern int DYN_FTRACE_TEST_NAME(void); 532 #endif 533 534 extern int ring_buffer_expanded; 535 extern bool tracing_selftest_disabled; 536 DECLARE_PER_CPU(local_t, ftrace_cpu_disabled); 537 538 #ifdef CONFIG_FTRACE_STARTUP_TEST 539 extern int trace_selftest_startup_function(struct tracer *trace, 540 struct trace_array *tr); 541 extern int trace_selftest_startup_function_graph(struct tracer *trace, 542 struct trace_array *tr); 543 extern int trace_selftest_startup_irqsoff(struct tracer *trace, 544 struct trace_array *tr); 545 extern int trace_selftest_startup_preemptoff(struct tracer *trace, 546 struct trace_array *tr); 547 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace, 548 struct trace_array *tr); 549 extern int trace_selftest_startup_wakeup(struct tracer *trace, 550 struct trace_array *tr); 551 extern int trace_selftest_startup_nop(struct tracer *trace, 552 struct trace_array *tr); 553 extern int trace_selftest_startup_sched_switch(struct tracer *trace, 554 struct trace_array *tr); 555 extern int trace_selftest_startup_sysprof(struct tracer *trace, 556 struct trace_array *tr); 557 extern int trace_selftest_startup_branch(struct tracer *trace, 558 struct trace_array *tr); 559 extern int trace_selftest_startup_hw_branches(struct tracer *trace, 560 struct trace_array *tr); 561 #endif /* CONFIG_FTRACE_STARTUP_TEST */ 562 563 extern void *head_page(struct trace_array_cpu *data); 564 extern unsigned long long ns2usecs(cycle_t nsec); 565 extern int 566 trace_vbprintk(unsigned long ip, const char *fmt, va_list args); 567 extern int 568 trace_vprintk(unsigned long ip, const char *fmt, va_list args); 569 extern int 570 trace_array_vprintk(struct trace_array *tr, 571 unsigned long ip, const char *fmt, va_list args); 572 int trace_array_printk(struct trace_array *tr, 573 unsigned long ip, const char *fmt, ...); 574 575 extern unsigned long trace_flags; 576 577 extern int trace_clock_id; 578 579 /* Standard output formatting function used for function return traces */ 580 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 581 extern enum print_line_t print_graph_function(struct trace_iterator *iter); 582 extern enum print_line_t 583 trace_print_graph_duration(unsigned long long duration, struct trace_seq *s); 584 585 #ifdef CONFIG_DYNAMIC_FTRACE 586 /* TODO: make this variable */ 587 #define FTRACE_GRAPH_MAX_FUNCS 32 588 extern int ftrace_graph_count; 589 extern unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS]; 590 591 static inline int ftrace_graph_addr(unsigned long addr) 592 { 593 int i; 594 595 if (!ftrace_graph_count || test_tsk_trace_graph(current)) 596 return 1; 597 598 for (i = 0; i < ftrace_graph_count; i++) { 599 if (addr == ftrace_graph_funcs[i]) 600 return 1; 601 } 602 603 return 0; 604 } 605 #else 606 static inline int ftrace_trace_addr(unsigned long addr) 607 { 608 return 1; 609 } 610 static inline int ftrace_graph_addr(unsigned long addr) 611 { 612 return 1; 613 } 614 #endif /* CONFIG_DYNAMIC_FTRACE */ 615 #else /* CONFIG_FUNCTION_GRAPH_TRACER */ 616 static inline enum print_line_t 617 print_graph_function(struct trace_iterator *iter) 618 { 619 return TRACE_TYPE_UNHANDLED; 620 } 621 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ 622 623 extern struct pid *ftrace_pid_trace; 624 625 #ifdef CONFIG_FUNCTION_TRACER 626 static inline int ftrace_trace_task(struct task_struct *task) 627 { 628 if (!ftrace_pid_trace) 629 return 1; 630 631 return test_tsk_trace_trace(task); 632 } 633 #else 634 static inline int ftrace_trace_task(struct task_struct *task) 635 { 636 return 1; 637 } 638 #endif 639 640 /* 641 * trace_iterator_flags is an enumeration that defines bit 642 * positions into trace_flags that controls the output. 643 * 644 * NOTE: These bits must match the trace_options array in 645 * trace.c. 646 */ 647 enum trace_iterator_flags { 648 TRACE_ITER_PRINT_PARENT = 0x01, 649 TRACE_ITER_SYM_OFFSET = 0x02, 650 TRACE_ITER_SYM_ADDR = 0x04, 651 TRACE_ITER_VERBOSE = 0x08, 652 TRACE_ITER_RAW = 0x10, 653 TRACE_ITER_HEX = 0x20, 654 TRACE_ITER_BIN = 0x40, 655 TRACE_ITER_BLOCK = 0x80, 656 TRACE_ITER_STACKTRACE = 0x100, 657 TRACE_ITER_SCHED_TREE = 0x200, 658 TRACE_ITER_PRINTK = 0x400, 659 TRACE_ITER_PREEMPTONLY = 0x800, 660 TRACE_ITER_BRANCH = 0x1000, 661 TRACE_ITER_ANNOTATE = 0x2000, 662 TRACE_ITER_USERSTACKTRACE = 0x4000, 663 TRACE_ITER_SYM_USEROBJ = 0x8000, 664 TRACE_ITER_PRINTK_MSGONLY = 0x10000, 665 TRACE_ITER_CONTEXT_INFO = 0x20000, /* Print pid/cpu/time */ 666 TRACE_ITER_LATENCY_FMT = 0x40000, 667 TRACE_ITER_SLEEP_TIME = 0x80000, 668 TRACE_ITER_GRAPH_TIME = 0x100000, 669 }; 670 671 /* 672 * TRACE_ITER_SYM_MASK masks the options in trace_flags that 673 * control the output of kernel symbols. 674 */ 675 #define TRACE_ITER_SYM_MASK \ 676 (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR) 677 678 extern struct tracer nop_trace; 679 680 /** 681 * ftrace_preempt_disable - disable preemption scheduler safe 682 * 683 * When tracing can happen inside the scheduler, there exists 684 * cases that the tracing might happen before the need_resched 685 * flag is checked. If this happens and the tracer calls 686 * preempt_enable (after a disable), a schedule might take place 687 * causing an infinite recursion. 688 * 689 * To prevent this, we read the need_resched flag before 690 * disabling preemption. When we want to enable preemption we 691 * check the flag, if it is set, then we call preempt_enable_no_resched. 692 * Otherwise, we call preempt_enable. 693 * 694 * The rational for doing the above is that if need_resched is set 695 * and we have yet to reschedule, we are either in an atomic location 696 * (where we do not need to check for scheduling) or we are inside 697 * the scheduler and do not want to resched. 698 */ 699 static inline int ftrace_preempt_disable(void) 700 { 701 int resched; 702 703 resched = need_resched(); 704 preempt_disable_notrace(); 705 706 return resched; 707 } 708 709 /** 710 * ftrace_preempt_enable - enable preemption scheduler safe 711 * @resched: the return value from ftrace_preempt_disable 712 * 713 * This is a scheduler safe way to enable preemption and not miss 714 * any preemption checks. The disabled saved the state of preemption. 715 * If resched is set, then we are either inside an atomic or 716 * are inside the scheduler (we would have already scheduled 717 * otherwise). In this case, we do not want to call normal 718 * preempt_enable, but preempt_enable_no_resched instead. 719 */ 720 static inline void ftrace_preempt_enable(int resched) 721 { 722 if (resched) 723 preempt_enable_no_resched_notrace(); 724 else 725 preempt_enable_notrace(); 726 } 727 728 #ifdef CONFIG_BRANCH_TRACER 729 extern int enable_branch_tracing(struct trace_array *tr); 730 extern void disable_branch_tracing(void); 731 static inline int trace_branch_enable(struct trace_array *tr) 732 { 733 if (trace_flags & TRACE_ITER_BRANCH) 734 return enable_branch_tracing(tr); 735 return 0; 736 } 737 static inline void trace_branch_disable(void) 738 { 739 /* due to races, always disable */ 740 disable_branch_tracing(); 741 } 742 #else 743 static inline int trace_branch_enable(struct trace_array *tr) 744 { 745 return 0; 746 } 747 static inline void trace_branch_disable(void) 748 { 749 } 750 #endif /* CONFIG_BRANCH_TRACER */ 751 752 /* set ring buffers to default size if not already done so */ 753 int tracing_update_buffers(void); 754 755 /* trace event type bit fields, not numeric */ 756 enum { 757 TRACE_EVENT_TYPE_PRINTF = 1, 758 TRACE_EVENT_TYPE_RAW = 2, 759 }; 760 761 struct ftrace_event_field { 762 struct list_head link; 763 char *name; 764 char *type; 765 int filter_type; 766 int offset; 767 int size; 768 int is_signed; 769 }; 770 771 struct event_filter { 772 int n_preds; 773 struct filter_pred **preds; 774 char *filter_string; 775 bool no_reset; 776 }; 777 778 struct event_subsystem { 779 struct list_head list; 780 const char *name; 781 struct dentry *entry; 782 struct event_filter *filter; 783 int nr_events; 784 }; 785 786 struct filter_pred; 787 788 typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event, 789 int val1, int val2); 790 791 struct filter_pred { 792 filter_pred_fn_t fn; 793 u64 val; 794 char str_val[MAX_FILTER_STR_VAL]; 795 int str_len; 796 char *field_name; 797 int offset; 798 int not; 799 int op; 800 int pop_n; 801 }; 802 803 extern void print_event_filter(struct ftrace_event_call *call, 804 struct trace_seq *s); 805 extern int apply_event_filter(struct ftrace_event_call *call, 806 char *filter_string); 807 extern int apply_subsystem_event_filter(struct event_subsystem *system, 808 char *filter_string); 809 extern void print_subsystem_event_filter(struct event_subsystem *system, 810 struct trace_seq *s); 811 extern int filter_assign_type(const char *type); 812 813 static inline int 814 filter_check_discard(struct ftrace_event_call *call, void *rec, 815 struct ring_buffer *buffer, 816 struct ring_buffer_event *event) 817 { 818 if (unlikely(call->filter_active) && !filter_match_preds(call, rec)) { 819 ring_buffer_discard_commit(buffer, event); 820 return 1; 821 } 822 823 return 0; 824 } 825 826 #define DEFINE_COMPARISON_PRED(type) \ 827 static int filter_pred_##type(struct filter_pred *pred, void *event, \ 828 int val1, int val2) \ 829 { \ 830 type *addr = (type *)(event + pred->offset); \ 831 type val = (type)pred->val; \ 832 int match = 0; \ 833 \ 834 switch (pred->op) { \ 835 case OP_LT: \ 836 match = (*addr < val); \ 837 break; \ 838 case OP_LE: \ 839 match = (*addr <= val); \ 840 break; \ 841 case OP_GT: \ 842 match = (*addr > val); \ 843 break; \ 844 case OP_GE: \ 845 match = (*addr >= val); \ 846 break; \ 847 default: \ 848 break; \ 849 } \ 850 \ 851 return match; \ 852 } 853 854 #define DEFINE_EQUALITY_PRED(size) \ 855 static int filter_pred_##size(struct filter_pred *pred, void *event, \ 856 int val1, int val2) \ 857 { \ 858 u##size *addr = (u##size *)(event + pred->offset); \ 859 u##size val = (u##size)pred->val; \ 860 int match; \ 861 \ 862 match = (val == *addr) ^ pred->not; \ 863 \ 864 return match; \ 865 } 866 867 extern struct mutex event_mutex; 868 extern struct list_head ftrace_events; 869 870 extern const char *__start___trace_bprintk_fmt[]; 871 extern const char *__stop___trace_bprintk_fmt[]; 872 873 #undef TRACE_EVENT_FORMAT 874 #define TRACE_EVENT_FORMAT(call, proto, args, fmt, tstruct, tpfmt) \ 875 extern struct ftrace_event_call event_##call; 876 #undef TRACE_EVENT_FORMAT_NOFILTER 877 #define TRACE_EVENT_FORMAT_NOFILTER(call, proto, args, fmt, tstruct, tpfmt) 878 #include "trace_event_types.h" 879 880 #endif /* _LINUX_KERNEL_TRACE_H */ 881