1 2#ifndef _LINUX_KERNEL_TRACE_H 3#define _LINUX_KERNEL_TRACE_H 4 5#include <linux/fs.h> 6#include <linux/atomic.h> 7#include <linux/sched.h> 8#include <linux/clocksource.h> 9#include <linux/ring_buffer.h> 10#include <linux/mmiotrace.h> 11#include <linux/tracepoint.h> 12#include <linux/ftrace.h> 13#include <linux/hw_breakpoint.h> 14#include <linux/trace_seq.h> 15#include <linux/ftrace_event.h> 16#include <linux/compiler.h> 17 18#ifdef CONFIG_FTRACE_SYSCALLS 19#include <asm/unistd.h> /* For NR_SYSCALLS */ 20#include <asm/syscall.h> /* some archs define it here */ 21#endif 22 23enum trace_type { 24 __TRACE_FIRST_TYPE = 0, 25 26 TRACE_FN, 27 TRACE_CTX, 28 TRACE_WAKE, 29 TRACE_STACK, 30 TRACE_PRINT, 31 TRACE_BPRINT, 32 TRACE_MMIO_RW, 33 TRACE_MMIO_MAP, 34 TRACE_BRANCH, 35 TRACE_GRAPH_RET, 36 TRACE_GRAPH_ENT, 37 TRACE_USER_STACK, 38 TRACE_BLK, 39 TRACE_BPUTS, 40 41 __TRACE_LAST_TYPE, 42}; 43 44 45#undef __field 46#define __field(type, item) type item; 47 48#undef __field_struct 49#define __field_struct(type, item) __field(type, item) 50 51#undef __field_desc 52#define __field_desc(type, container, item) 53 54#undef __array 55#define __array(type, item, size) type item[size]; 56 57#undef __array_desc 58#define __array_desc(type, container, item, size) 59 60#undef __dynamic_array 61#define __dynamic_array(type, item) type item[]; 62 63#undef F_STRUCT 64#define F_STRUCT(args...) args 65 66#undef FTRACE_ENTRY 67#define FTRACE_ENTRY(name, struct_name, id, tstruct, print, filter) \ 68 struct struct_name { \ 69 struct trace_entry ent; \ 70 tstruct \ 71 } 72 73#undef TP_ARGS 74#define TP_ARGS(args...) args 75 76#undef FTRACE_ENTRY_DUP 77#define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk, filter) 78 79#undef FTRACE_ENTRY_REG 80#define FTRACE_ENTRY_REG(name, struct_name, id, tstruct, print, \ 81 filter, regfn) \ 82 FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print), \ 83 filter) 84 85#include "trace_entries.h" 86 87/* 88 * syscalls are special, and need special handling, this is why 89 * they are not included in trace_entries.h 90 */ 91struct syscall_trace_enter { 92 struct trace_entry ent; 93 int nr; 94 unsigned long args[]; 95}; 96 97struct syscall_trace_exit { 98 struct trace_entry ent; 99 int nr; 100 long ret; 101}; 102 103struct kprobe_trace_entry_head { 104 struct trace_entry ent; 105 unsigned long ip; 106}; 107 108struct kretprobe_trace_entry_head { 109 struct trace_entry ent; 110 unsigned long func; 111 unsigned long ret_ip; 112}; 113 114/* 115 * trace_flag_type is an enumeration that holds different 116 * states when a trace occurs. These are: 117 * IRQS_OFF - interrupts were disabled 118 * IRQS_NOSUPPORT - arch does not support irqs_disabled_flags 119 * NEED_RESCHED - reschedule is requested 120 * HARDIRQ - inside an interrupt handler 121 * SOFTIRQ - inside a softirq handler 122 */ 123enum trace_flag_type { 124 TRACE_FLAG_IRQS_OFF = 0x01, 125 TRACE_FLAG_IRQS_NOSUPPORT = 0x02, 126 TRACE_FLAG_NEED_RESCHED = 0x04, 127 TRACE_FLAG_HARDIRQ = 0x08, 128 TRACE_FLAG_SOFTIRQ = 0x10, 129 TRACE_FLAG_PREEMPT_RESCHED = 0x20, 130}; 131 132#define TRACE_BUF_SIZE 1024 133 134struct trace_array; 135 136/* 137 * The CPU trace array - it consists of thousands of trace entries 138 * plus some other descriptor data: (for example which task started 139 * the trace, etc.) 140 */ 141struct trace_array_cpu { 142 atomic_t disabled; 143 void *buffer_page; /* ring buffer spare */ 144 145 unsigned long entries; 146 unsigned long saved_latency; 147 unsigned long critical_start; 148 unsigned long critical_end; 149 unsigned long critical_sequence; 150 unsigned long nice; 151 unsigned long policy; 152 unsigned long rt_priority; 153 unsigned long skipped_entries; 154 cycle_t preempt_timestamp; 155 pid_t pid; 156 kuid_t uid; 157 char comm[TASK_COMM_LEN]; 158}; 159 160struct tracer; 161 162struct trace_buffer { 163 struct trace_array *tr; 164 struct ring_buffer *buffer; 165 struct trace_array_cpu __percpu *data; 166 cycle_t time_start; 167 int cpu; 168}; 169 170/* 171 * The trace array - an array of per-CPU trace arrays. This is the 172 * highest level data structure that individual tracers deal with. 173 * They have on/off state as well: 174 */ 175struct trace_array { 176 struct list_head list; 177 char *name; 178 struct trace_buffer trace_buffer; 179#ifdef CONFIG_TRACER_MAX_TRACE 180 /* 181 * The max_buffer is used to snapshot the trace when a maximum 182 * latency is reached, or when the user initiates a snapshot. 183 * Some tracers will use this to store a maximum trace while 184 * it continues examining live traces. 185 * 186 * The buffers for the max_buffer are set up the same as the trace_buffer 187 * When a snapshot is taken, the buffer of the max_buffer is swapped 188 * with the buffer of the trace_buffer and the buffers are reset for 189 * the trace_buffer so the tracing can continue. 190 */ 191 struct trace_buffer max_buffer; 192 bool allocated_snapshot; 193 unsigned long max_latency; 194#endif 195 /* 196 * max_lock is used to protect the swapping of buffers 197 * when taking a max snapshot. The buffers themselves are 198 * protected by per_cpu spinlocks. But the action of the swap 199 * needs its own lock. 200 * 201 * This is defined as a arch_spinlock_t in order to help 202 * with performance when lockdep debugging is enabled. 203 * 204 * It is also used in other places outside the update_max_tr 205 * so it needs to be defined outside of the 206 * CONFIG_TRACER_MAX_TRACE. 207 */ 208 arch_spinlock_t max_lock; 209 int buffer_disabled; 210#ifdef CONFIG_FTRACE_SYSCALLS 211 int sys_refcount_enter; 212 int sys_refcount_exit; 213 struct ftrace_event_file __rcu *enter_syscall_files[NR_syscalls]; 214 struct ftrace_event_file __rcu *exit_syscall_files[NR_syscalls]; 215#endif 216 int stop_count; 217 int clock_id; 218 struct tracer *current_trace; 219 unsigned int flags; 220 raw_spinlock_t start_lock; 221 struct dentry *dir; 222 struct dentry *options; 223 struct dentry *percpu_dir; 224 struct dentry *event_dir; 225 struct list_head systems; 226 struct list_head events; 227 cpumask_var_t tracing_cpumask; /* only trace on set CPUs */ 228 int ref; 229#ifdef CONFIG_FUNCTION_TRACER 230 struct ftrace_ops *ops; 231 /* function tracing enabled */ 232 int function_enabled; 233#endif 234}; 235 236enum { 237 TRACE_ARRAY_FL_GLOBAL = (1 << 0) 238}; 239 240extern struct list_head ftrace_trace_arrays; 241 242extern struct mutex trace_types_lock; 243 244extern int trace_array_get(struct trace_array *tr); 245extern void trace_array_put(struct trace_array *tr); 246 247/* 248 * The global tracer (top) should be the first trace array added, 249 * but we check the flag anyway. 250 */ 251static inline struct trace_array *top_trace_array(void) 252{ 253 struct trace_array *tr; 254 255 if (list_empty(&ftrace_trace_arrays)) 256 return NULL; 257 258 tr = list_entry(ftrace_trace_arrays.prev, 259 typeof(*tr), list); 260 WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL)); 261 return tr; 262} 263 264#define FTRACE_CMP_TYPE(var, type) \ 265 __builtin_types_compatible_p(typeof(var), type *) 266 267#undef IF_ASSIGN 268#define IF_ASSIGN(var, entry, etype, id) \ 269 if (FTRACE_CMP_TYPE(var, etype)) { \ 270 var = (typeof(var))(entry); \ 271 WARN_ON(id && (entry)->type != id); \ 272 break; \ 273 } 274 275/* Will cause compile errors if type is not found. */ 276extern void __ftrace_bad_type(void); 277 278/* 279 * The trace_assign_type is a verifier that the entry type is 280 * the same as the type being assigned. To add new types simply 281 * add a line with the following format: 282 * 283 * IF_ASSIGN(var, ent, type, id); 284 * 285 * Where "type" is the trace type that includes the trace_entry 286 * as the "ent" item. And "id" is the trace identifier that is 287 * used in the trace_type enum. 288 * 289 * If the type can have more than one id, then use zero. 290 */ 291#define trace_assign_type(var, ent) \ 292 do { \ 293 IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN); \ 294 IF_ASSIGN(var, ent, struct ctx_switch_entry, 0); \ 295 IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK); \ 296 IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\ 297 IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT); \ 298 IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT); \ 299 IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS); \ 300 IF_ASSIGN(var, ent, struct trace_mmiotrace_rw, \ 301 TRACE_MMIO_RW); \ 302 IF_ASSIGN(var, ent, struct trace_mmiotrace_map, \ 303 TRACE_MMIO_MAP); \ 304 IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \ 305 IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry, \ 306 TRACE_GRAPH_ENT); \ 307 IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry, \ 308 TRACE_GRAPH_RET); \ 309 __ftrace_bad_type(); \ 310 } while (0) 311 312/* 313 * An option specific to a tracer. This is a boolean value. 314 * The bit is the bit index that sets its value on the 315 * flags value in struct tracer_flags. 316 */ 317struct tracer_opt { 318 const char *name; /* Will appear on the trace_options file */ 319 u32 bit; /* Mask assigned in val field in tracer_flags */ 320}; 321 322/* 323 * The set of specific options for a tracer. Your tracer 324 * have to set the initial value of the flags val. 325 */ 326struct tracer_flags { 327 u32 val; 328 struct tracer_opt *opts; 329}; 330 331/* Makes more easy to define a tracer opt */ 332#define TRACER_OPT(s, b) .name = #s, .bit = b 333 334 335/** 336 * struct tracer - a specific tracer and its callbacks to interact with debugfs 337 * @name: the name chosen to select it on the available_tracers file 338 * @init: called when one switches to this tracer (echo name > current_tracer) 339 * @reset: called when one switches to another tracer 340 * @start: called when tracing is unpaused (echo 1 > tracing_enabled) 341 * @stop: called when tracing is paused (echo 0 > tracing_enabled) 342 * @update_thresh: called when tracing_thresh is updated 343 * @open: called when the trace file is opened 344 * @pipe_open: called when the trace_pipe file is opened 345 * @close: called when the trace file is released 346 * @pipe_close: called when the trace_pipe file is released 347 * @read: override the default read callback on trace_pipe 348 * @splice_read: override the default splice_read callback on trace_pipe 349 * @selftest: selftest to run on boot (see trace_selftest.c) 350 * @print_headers: override the first lines that describe your columns 351 * @print_line: callback that prints a trace 352 * @set_flag: signals one of your private flags changed (trace_options file) 353 * @flags: your private flags 354 */ 355struct tracer { 356 const char *name; 357 int (*init)(struct trace_array *tr); 358 void (*reset)(struct trace_array *tr); 359 void (*start)(struct trace_array *tr); 360 void (*stop)(struct trace_array *tr); 361 int (*update_thresh)(struct trace_array *tr); 362 void (*open)(struct trace_iterator *iter); 363 void (*pipe_open)(struct trace_iterator *iter); 364 void (*close)(struct trace_iterator *iter); 365 void (*pipe_close)(struct trace_iterator *iter); 366 ssize_t (*read)(struct trace_iterator *iter, 367 struct file *filp, char __user *ubuf, 368 size_t cnt, loff_t *ppos); 369 ssize_t (*splice_read)(struct trace_iterator *iter, 370 struct file *filp, 371 loff_t *ppos, 372 struct pipe_inode_info *pipe, 373 size_t len, 374 unsigned int flags); 375#ifdef CONFIG_FTRACE_STARTUP_TEST 376 int (*selftest)(struct tracer *trace, 377 struct trace_array *tr); 378#endif 379 void (*print_header)(struct seq_file *m); 380 enum print_line_t (*print_line)(struct trace_iterator *iter); 381 /* If you handled the flag setting, return 0 */ 382 int (*set_flag)(struct trace_array *tr, 383 u32 old_flags, u32 bit, int set); 384 /* Return 0 if OK with change, else return non-zero */ 385 int (*flag_changed)(struct trace_array *tr, 386 u32 mask, int set); 387 struct tracer *next; 388 struct tracer_flags *flags; 389 int enabled; 390 bool print_max; 391 bool allow_instances; 392#ifdef CONFIG_TRACER_MAX_TRACE 393 bool use_max_tr; 394#endif 395}; 396 397 398/* Only current can touch trace_recursion */ 399 400/* 401 * For function tracing recursion: 402 * The order of these bits are important. 403 * 404 * When function tracing occurs, the following steps are made: 405 * If arch does not support a ftrace feature: 406 * call internal function (uses INTERNAL bits) which calls... 407 * If callback is registered to the "global" list, the list 408 * function is called and recursion checks the GLOBAL bits. 409 * then this function calls... 410 * The function callback, which can use the FTRACE bits to 411 * check for recursion. 412 * 413 * Now if the arch does not suppport a feature, and it calls 414 * the global list function which calls the ftrace callback 415 * all three of these steps will do a recursion protection. 416 * There's no reason to do one if the previous caller already 417 * did. The recursion that we are protecting against will 418 * go through the same steps again. 419 * 420 * To prevent the multiple recursion checks, if a recursion 421 * bit is set that is higher than the MAX bit of the current 422 * check, then we know that the check was made by the previous 423 * caller, and we can skip the current check. 424 */ 425enum { 426 TRACE_BUFFER_BIT, 427 TRACE_BUFFER_NMI_BIT, 428 TRACE_BUFFER_IRQ_BIT, 429 TRACE_BUFFER_SIRQ_BIT, 430 431 /* Start of function recursion bits */ 432 TRACE_FTRACE_BIT, 433 TRACE_FTRACE_NMI_BIT, 434 TRACE_FTRACE_IRQ_BIT, 435 TRACE_FTRACE_SIRQ_BIT, 436 437 /* INTERNAL_BITs must be greater than FTRACE_BITs */ 438 TRACE_INTERNAL_BIT, 439 TRACE_INTERNAL_NMI_BIT, 440 TRACE_INTERNAL_IRQ_BIT, 441 TRACE_INTERNAL_SIRQ_BIT, 442 443 TRACE_CONTROL_BIT, 444 445/* 446 * Abuse of the trace_recursion. 447 * As we need a way to maintain state if we are tracing the function 448 * graph in irq because we want to trace a particular function that 449 * was called in irq context but we have irq tracing off. Since this 450 * can only be modified by current, we can reuse trace_recursion. 451 */ 452 TRACE_IRQ_BIT, 453}; 454 455#define trace_recursion_set(bit) do { (current)->trace_recursion |= (1<<(bit)); } while (0) 456#define trace_recursion_clear(bit) do { (current)->trace_recursion &= ~(1<<(bit)); } while (0) 457#define trace_recursion_test(bit) ((current)->trace_recursion & (1<<(bit))) 458 459#define TRACE_CONTEXT_BITS 4 460 461#define TRACE_FTRACE_START TRACE_FTRACE_BIT 462#define TRACE_FTRACE_MAX ((1 << (TRACE_FTRACE_START + TRACE_CONTEXT_BITS)) - 1) 463 464#define TRACE_LIST_START TRACE_INTERNAL_BIT 465#define TRACE_LIST_MAX ((1 << (TRACE_LIST_START + TRACE_CONTEXT_BITS)) - 1) 466 467#define TRACE_CONTEXT_MASK TRACE_LIST_MAX 468 469static __always_inline int trace_get_context_bit(void) 470{ 471 int bit; 472 473 if (in_interrupt()) { 474 if (in_nmi()) 475 bit = 0; 476 477 else if (in_irq()) 478 bit = 1; 479 else 480 bit = 2; 481 } else 482 bit = 3; 483 484 return bit; 485} 486 487static __always_inline int trace_test_and_set_recursion(int start, int max) 488{ 489 unsigned int val = current->trace_recursion; 490 int bit; 491 492 /* A previous recursion check was made */ 493 if ((val & TRACE_CONTEXT_MASK) > max) 494 return 0; 495 496 bit = trace_get_context_bit() + start; 497 if (unlikely(val & (1 << bit))) 498 return -1; 499 500 val |= 1 << bit; 501 current->trace_recursion = val; 502 barrier(); 503 504 return bit; 505} 506 507static __always_inline void trace_clear_recursion(int bit) 508{ 509 unsigned int val = current->trace_recursion; 510 511 if (!bit) 512 return; 513 514 bit = 1 << bit; 515 val &= ~bit; 516 517 barrier(); 518 current->trace_recursion = val; 519} 520 521static inline struct ring_buffer_iter * 522trace_buffer_iter(struct trace_iterator *iter, int cpu) 523{ 524 if (iter->buffer_iter && iter->buffer_iter[cpu]) 525 return iter->buffer_iter[cpu]; 526 return NULL; 527} 528 529int tracer_init(struct tracer *t, struct trace_array *tr); 530int tracing_is_enabled(void); 531void tracing_reset(struct trace_buffer *buf, int cpu); 532void tracing_reset_online_cpus(struct trace_buffer *buf); 533void tracing_reset_current(int cpu); 534void tracing_reset_all_online_cpus(void); 535int tracing_open_generic(struct inode *inode, struct file *filp); 536bool tracing_is_disabled(void); 537struct dentry *trace_create_file(const char *name, 538 umode_t mode, 539 struct dentry *parent, 540 void *data, 541 const struct file_operations *fops); 542 543struct dentry *tracing_init_dentry_tr(struct trace_array *tr); 544struct dentry *tracing_init_dentry(void); 545 546struct ring_buffer_event; 547 548struct ring_buffer_event * 549trace_buffer_lock_reserve(struct ring_buffer *buffer, 550 int type, 551 unsigned long len, 552 unsigned long flags, 553 int pc); 554 555struct trace_entry *tracing_get_trace_entry(struct trace_array *tr, 556 struct trace_array_cpu *data); 557 558struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, 559 int *ent_cpu, u64 *ent_ts); 560 561void __buffer_unlock_commit(struct ring_buffer *buffer, 562 struct ring_buffer_event *event); 563 564int trace_empty(struct trace_iterator *iter); 565 566void *trace_find_next_entry_inc(struct trace_iterator *iter); 567 568void trace_init_global_iter(struct trace_iterator *iter); 569 570void tracing_iter_reset(struct trace_iterator *iter, int cpu); 571 572void tracing_sched_switch_trace(struct trace_array *tr, 573 struct task_struct *prev, 574 struct task_struct *next, 575 unsigned long flags, int pc); 576 577void tracing_sched_wakeup_trace(struct trace_array *tr, 578 struct task_struct *wakee, 579 struct task_struct *cur, 580 unsigned long flags, int pc); 581void trace_function(struct trace_array *tr, 582 unsigned long ip, 583 unsigned long parent_ip, 584 unsigned long flags, int pc); 585void trace_graph_function(struct trace_array *tr, 586 unsigned long ip, 587 unsigned long parent_ip, 588 unsigned long flags, int pc); 589void trace_latency_header(struct seq_file *m); 590void trace_default_header(struct seq_file *m); 591void print_trace_header(struct seq_file *m, struct trace_iterator *iter); 592int trace_empty(struct trace_iterator *iter); 593 594void trace_graph_return(struct ftrace_graph_ret *trace); 595int trace_graph_entry(struct ftrace_graph_ent *trace); 596void set_graph_array(struct trace_array *tr); 597 598void tracing_start_cmdline_record(void); 599void tracing_stop_cmdline_record(void); 600void tracing_sched_switch_assign_trace(struct trace_array *tr); 601void tracing_stop_sched_switch_record(void); 602void tracing_start_sched_switch_record(void); 603int register_tracer(struct tracer *type); 604int is_tracing_stopped(void); 605 606loff_t tracing_lseek(struct file *file, loff_t offset, int whence); 607 608extern cpumask_var_t __read_mostly tracing_buffer_mask; 609 610#define for_each_tracing_cpu(cpu) \ 611 for_each_cpu(cpu, tracing_buffer_mask) 612 613extern unsigned long nsecs_to_usecs(unsigned long nsecs); 614 615extern unsigned long tracing_thresh; 616 617#ifdef CONFIG_TRACER_MAX_TRACE 618void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu); 619void update_max_tr_single(struct trace_array *tr, 620 struct task_struct *tsk, int cpu); 621#endif /* CONFIG_TRACER_MAX_TRACE */ 622 623#ifdef CONFIG_STACKTRACE 624void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags, 625 int skip, int pc); 626 627void ftrace_trace_stack_regs(struct ring_buffer *buffer, unsigned long flags, 628 int skip, int pc, struct pt_regs *regs); 629 630void ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, 631 int pc); 632 633void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, 634 int pc); 635#else 636static inline void ftrace_trace_stack(struct ring_buffer *buffer, 637 unsigned long flags, int skip, int pc) 638{ 639} 640 641static inline void ftrace_trace_stack_regs(struct ring_buffer *buffer, 642 unsigned long flags, int skip, 643 int pc, struct pt_regs *regs) 644{ 645} 646 647static inline void ftrace_trace_userstack(struct ring_buffer *buffer, 648 unsigned long flags, int pc) 649{ 650} 651 652static inline void __trace_stack(struct trace_array *tr, unsigned long flags, 653 int skip, int pc) 654{ 655} 656#endif /* CONFIG_STACKTRACE */ 657 658extern cycle_t ftrace_now(int cpu); 659 660extern void trace_find_cmdline(int pid, char comm[]); 661extern int trace_find_tgid(int pid); 662 663#ifdef CONFIG_DYNAMIC_FTRACE 664extern unsigned long ftrace_update_tot_cnt; 665#endif 666#define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func 667extern int DYN_FTRACE_TEST_NAME(void); 668#define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2 669extern int DYN_FTRACE_TEST_NAME2(void); 670 671extern bool ring_buffer_expanded; 672extern bool tracing_selftest_disabled; 673DECLARE_PER_CPU(int, ftrace_cpu_disabled); 674 675#ifdef CONFIG_FTRACE_STARTUP_TEST 676extern int trace_selftest_startup_function(struct tracer *trace, 677 struct trace_array *tr); 678extern int trace_selftest_startup_function_graph(struct tracer *trace, 679 struct trace_array *tr); 680extern int trace_selftest_startup_irqsoff(struct tracer *trace, 681 struct trace_array *tr); 682extern int trace_selftest_startup_preemptoff(struct tracer *trace, 683 struct trace_array *tr); 684extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace, 685 struct trace_array *tr); 686extern int trace_selftest_startup_wakeup(struct tracer *trace, 687 struct trace_array *tr); 688extern int trace_selftest_startup_nop(struct tracer *trace, 689 struct trace_array *tr); 690extern int trace_selftest_startup_sched_switch(struct tracer *trace, 691 struct trace_array *tr); 692extern int trace_selftest_startup_branch(struct tracer *trace, 693 struct trace_array *tr); 694/* 695 * Tracer data references selftest functions that only occur 696 * on boot up. These can be __init functions. Thus, when selftests 697 * are enabled, then the tracers need to reference __init functions. 698 */ 699#define __tracer_data __refdata 700#else 701/* Tracers are seldom changed. Optimize when selftests are disabled. */ 702#define __tracer_data __read_mostly 703#endif /* CONFIG_FTRACE_STARTUP_TEST */ 704 705extern void *head_page(struct trace_array_cpu *data); 706extern unsigned long long ns2usecs(cycle_t nsec); 707extern int 708trace_vbprintk(unsigned long ip, const char *fmt, va_list args); 709extern int 710trace_vprintk(unsigned long ip, const char *fmt, va_list args); 711extern int 712trace_array_vprintk(struct trace_array *tr, 713 unsigned long ip, const char *fmt, va_list args); 714int trace_array_printk(struct trace_array *tr, 715 unsigned long ip, const char *fmt, ...); 716int trace_array_printk_buf(struct ring_buffer *buffer, 717 unsigned long ip, const char *fmt, ...); 718void trace_printk_seq(struct trace_seq *s); 719enum print_line_t print_trace_line(struct trace_iterator *iter); 720 721extern unsigned long trace_flags; 722 723/* Standard output formatting function used for function return traces */ 724#ifdef CONFIG_FUNCTION_GRAPH_TRACER 725 726/* Flag options */ 727#define TRACE_GRAPH_PRINT_OVERRUN 0x1 728#define TRACE_GRAPH_PRINT_CPU 0x2 729#define TRACE_GRAPH_PRINT_OVERHEAD 0x4 730#define TRACE_GRAPH_PRINT_PROC 0x8 731#define TRACE_GRAPH_PRINT_DURATION 0x10 732#define TRACE_GRAPH_PRINT_ABS_TIME 0x20 733#define TRACE_GRAPH_PRINT_IRQS 0x40 734#define TRACE_GRAPH_PRINT_TAIL 0x80 735#define TRACE_GRAPH_PRINT_FILL_SHIFT 28 736#define TRACE_GRAPH_PRINT_FILL_MASK (0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT) 737 738extern enum print_line_t 739print_graph_function_flags(struct trace_iterator *iter, u32 flags); 740extern void print_graph_headers_flags(struct seq_file *s, u32 flags); 741extern enum print_line_t 742trace_print_graph_duration(unsigned long long duration, struct trace_seq *s); 743extern void graph_trace_open(struct trace_iterator *iter); 744extern void graph_trace_close(struct trace_iterator *iter); 745extern int __trace_graph_entry(struct trace_array *tr, 746 struct ftrace_graph_ent *trace, 747 unsigned long flags, int pc); 748extern void __trace_graph_return(struct trace_array *tr, 749 struct ftrace_graph_ret *trace, 750 unsigned long flags, int pc); 751 752 753#ifdef CONFIG_DYNAMIC_FTRACE 754/* TODO: make this variable */ 755#define FTRACE_GRAPH_MAX_FUNCS 32 756extern int ftrace_graph_count; 757extern unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS]; 758extern int ftrace_graph_notrace_count; 759extern unsigned long ftrace_graph_notrace_funcs[FTRACE_GRAPH_MAX_FUNCS]; 760 761static inline int ftrace_graph_addr(unsigned long addr) 762{ 763 int i; 764 765 if (!ftrace_graph_count) 766 return 1; 767 768 for (i = 0; i < ftrace_graph_count; i++) { 769 if (addr == ftrace_graph_funcs[i]) { 770 /* 771 * If no irqs are to be traced, but a set_graph_function 772 * is set, and called by an interrupt handler, we still 773 * want to trace it. 774 */ 775 if (in_irq()) 776 trace_recursion_set(TRACE_IRQ_BIT); 777 else 778 trace_recursion_clear(TRACE_IRQ_BIT); 779 return 1; 780 } 781 } 782 783 return 0; 784} 785 786static inline int ftrace_graph_notrace_addr(unsigned long addr) 787{ 788 int i; 789 790 if (!ftrace_graph_notrace_count) 791 return 0; 792 793 for (i = 0; i < ftrace_graph_notrace_count; i++) { 794 if (addr == ftrace_graph_notrace_funcs[i]) 795 return 1; 796 } 797 798 return 0; 799} 800#else 801static inline int ftrace_graph_addr(unsigned long addr) 802{ 803 return 1; 804} 805 806static inline int ftrace_graph_notrace_addr(unsigned long addr) 807{ 808 return 0; 809} 810#endif /* CONFIG_DYNAMIC_FTRACE */ 811#else /* CONFIG_FUNCTION_GRAPH_TRACER */ 812static inline enum print_line_t 813print_graph_function_flags(struct trace_iterator *iter, u32 flags) 814{ 815 return TRACE_TYPE_UNHANDLED; 816} 817#endif /* CONFIG_FUNCTION_GRAPH_TRACER */ 818 819extern struct list_head ftrace_pids; 820 821#ifdef CONFIG_FUNCTION_TRACER 822extern bool ftrace_filter_param __initdata; 823static inline int ftrace_trace_task(struct task_struct *task) 824{ 825 if (list_empty(&ftrace_pids)) 826 return 1; 827 828 return test_tsk_trace_trace(task); 829} 830extern int ftrace_is_dead(void); 831int ftrace_create_function_files(struct trace_array *tr, 832 struct dentry *parent); 833void ftrace_destroy_function_files(struct trace_array *tr); 834void ftrace_init_global_array_ops(struct trace_array *tr); 835void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func); 836void ftrace_reset_array_ops(struct trace_array *tr); 837int using_ftrace_ops_list_func(void); 838#else 839static inline int ftrace_trace_task(struct task_struct *task) 840{ 841 return 1; 842} 843static inline int ftrace_is_dead(void) { return 0; } 844static inline int 845ftrace_create_function_files(struct trace_array *tr, 846 struct dentry *parent) 847{ 848 return 0; 849} 850static inline void ftrace_destroy_function_files(struct trace_array *tr) { } 851static inline __init void 852ftrace_init_global_array_ops(struct trace_array *tr) { } 853static inline void ftrace_reset_array_ops(struct trace_array *tr) { } 854/* ftace_func_t type is not defined, use macro instead of static inline */ 855#define ftrace_init_array_ops(tr, func) do { } while (0) 856#endif /* CONFIG_FUNCTION_TRACER */ 857 858#if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE) 859void ftrace_create_filter_files(struct ftrace_ops *ops, 860 struct dentry *parent); 861void ftrace_destroy_filter_files(struct ftrace_ops *ops); 862#else 863/* 864 * The ops parameter passed in is usually undefined. 865 * This must be a macro. 866 */ 867#define ftrace_create_filter_files(ops, parent) do { } while (0) 868#define ftrace_destroy_filter_files(ops) do { } while (0) 869#endif /* CONFIG_FUNCTION_TRACER && CONFIG_DYNAMIC_FTRACE */ 870 871int ftrace_event_is_function(struct ftrace_event_call *call); 872 873/* 874 * struct trace_parser - servers for reading the user input separated by spaces 875 * @cont: set if the input is not complete - no final space char was found 876 * @buffer: holds the parsed user input 877 * @idx: user input length 878 * @size: buffer size 879 */ 880struct trace_parser { 881 bool cont; 882 char *buffer; 883 unsigned idx; 884 unsigned size; 885}; 886 887static inline bool trace_parser_loaded(struct trace_parser *parser) 888{ 889 return (parser->idx != 0); 890} 891 892static inline bool trace_parser_cont(struct trace_parser *parser) 893{ 894 return parser->cont; 895} 896 897static inline void trace_parser_clear(struct trace_parser *parser) 898{ 899 parser->cont = false; 900 parser->idx = 0; 901} 902 903extern int trace_parser_get_init(struct trace_parser *parser, int size); 904extern void trace_parser_put(struct trace_parser *parser); 905extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf, 906 size_t cnt, loff_t *ppos); 907 908/* 909 * trace_iterator_flags is an enumeration that defines bit 910 * positions into trace_flags that controls the output. 911 * 912 * NOTE: These bits must match the trace_options array in 913 * trace.c. 914 */ 915enum trace_iterator_flags { 916 TRACE_ITER_PRINT_PARENT = 0x01, 917 TRACE_ITER_SYM_OFFSET = 0x02, 918 TRACE_ITER_SYM_ADDR = 0x04, 919 TRACE_ITER_VERBOSE = 0x08, 920 TRACE_ITER_RAW = 0x10, 921 TRACE_ITER_HEX = 0x20, 922 TRACE_ITER_BIN = 0x40, 923 TRACE_ITER_BLOCK = 0x80, 924 TRACE_ITER_STACKTRACE = 0x100, 925 TRACE_ITER_PRINTK = 0x200, 926 TRACE_ITER_PREEMPTONLY = 0x400, 927 TRACE_ITER_BRANCH = 0x800, 928 TRACE_ITER_ANNOTATE = 0x1000, 929 TRACE_ITER_USERSTACKTRACE = 0x2000, 930 TRACE_ITER_SYM_USEROBJ = 0x4000, 931 TRACE_ITER_PRINTK_MSGONLY = 0x8000, 932 TRACE_ITER_CONTEXT_INFO = 0x10000, /* Print pid/cpu/time */ 933 TRACE_ITER_LATENCY_FMT = 0x20000, 934 TRACE_ITER_SLEEP_TIME = 0x40000, 935 TRACE_ITER_GRAPH_TIME = 0x80000, 936 TRACE_ITER_RECORD_CMD = 0x100000, 937 TRACE_ITER_OVERWRITE = 0x200000, 938 TRACE_ITER_STOP_ON_FREE = 0x400000, 939 TRACE_ITER_IRQ_INFO = 0x800000, 940 TRACE_ITER_MARKERS = 0x1000000, 941 TRACE_ITER_FUNCTION = 0x2000000, 942 TRACE_ITER_TGID = 0x4000000, 943}; 944 945/* 946 * TRACE_ITER_SYM_MASK masks the options in trace_flags that 947 * control the output of kernel symbols. 948 */ 949#define TRACE_ITER_SYM_MASK \ 950 (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR) 951 952extern struct tracer nop_trace; 953 954#ifdef CONFIG_BRANCH_TRACER 955extern int enable_branch_tracing(struct trace_array *tr); 956extern void disable_branch_tracing(void); 957static inline int trace_branch_enable(struct trace_array *tr) 958{ 959 if (trace_flags & TRACE_ITER_BRANCH) 960 return enable_branch_tracing(tr); 961 return 0; 962} 963static inline void trace_branch_disable(void) 964{ 965 /* due to races, always disable */ 966 disable_branch_tracing(); 967} 968#else 969static inline int trace_branch_enable(struct trace_array *tr) 970{ 971 return 0; 972} 973static inline void trace_branch_disable(void) 974{ 975} 976#endif /* CONFIG_BRANCH_TRACER */ 977 978/* set ring buffers to default size if not already done so */ 979int tracing_update_buffers(void); 980 981struct ftrace_event_field { 982 struct list_head link; 983 const char *name; 984 const char *type; 985 int filter_type; 986 int offset; 987 int size; 988 int is_signed; 989}; 990 991struct event_filter { 992 int n_preds; /* Number assigned */ 993 int a_preds; /* allocated */ 994 struct filter_pred *preds; 995 struct filter_pred *root; 996 char *filter_string; 997}; 998 999struct event_subsystem { 1000 struct list_head list; 1001 const char *name; 1002 struct event_filter *filter; 1003 int ref_count; 1004}; 1005 1006struct ftrace_subsystem_dir { 1007 struct list_head list; 1008 struct event_subsystem *subsystem; 1009 struct trace_array *tr; 1010 struct dentry *entry; 1011 int ref_count; 1012 int nr_events; 1013}; 1014 1015#define FILTER_PRED_INVALID ((unsigned short)-1) 1016#define FILTER_PRED_IS_RIGHT (1 << 15) 1017#define FILTER_PRED_FOLD (1 << 15) 1018 1019/* 1020 * The max preds is the size of unsigned short with 1021 * two flags at the MSBs. One bit is used for both the IS_RIGHT 1022 * and FOLD flags. The other is reserved. 1023 * 1024 * 2^14 preds is way more than enough. 1025 */ 1026#define MAX_FILTER_PRED 16384 1027 1028struct filter_pred; 1029struct regex; 1030 1031typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event); 1032 1033typedef int (*regex_match_func)(char *str, struct regex *r, int len); 1034 1035enum regex_type { 1036 MATCH_FULL = 0, 1037 MATCH_FRONT_ONLY, 1038 MATCH_MIDDLE_ONLY, 1039 MATCH_END_ONLY, 1040}; 1041 1042struct regex { 1043 char pattern[MAX_FILTER_STR_VAL]; 1044 int len; 1045 int field_len; 1046 regex_match_func match; 1047}; 1048 1049struct filter_pred { 1050 filter_pred_fn_t fn; 1051 u64 val; 1052 struct regex regex; 1053 unsigned short *ops; 1054 struct ftrace_event_field *field; 1055 int offset; 1056 int not; 1057 int op; 1058 unsigned short index; 1059 unsigned short parent; 1060 unsigned short left; 1061 unsigned short right; 1062}; 1063 1064extern enum regex_type 1065filter_parse_regex(char *buff, int len, char **search, int *not); 1066extern void print_event_filter(struct ftrace_event_file *file, 1067 struct trace_seq *s); 1068extern int apply_event_filter(struct ftrace_event_file *file, 1069 char *filter_string); 1070extern int apply_subsystem_event_filter(struct ftrace_subsystem_dir *dir, 1071 char *filter_string); 1072extern void print_subsystem_event_filter(struct event_subsystem *system, 1073 struct trace_seq *s); 1074extern int filter_assign_type(const char *type); 1075extern int create_event_filter(struct ftrace_event_call *call, 1076 char *filter_str, bool set_str, 1077 struct event_filter **filterp); 1078extern void free_event_filter(struct event_filter *filter); 1079 1080struct ftrace_event_field * 1081trace_find_event_field(struct ftrace_event_call *call, char *name); 1082 1083extern void trace_event_enable_cmd_record(bool enable); 1084extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr); 1085extern int event_trace_del_tracer(struct trace_array *tr); 1086 1087extern struct ftrace_event_file *find_event_file(struct trace_array *tr, 1088 const char *system, 1089 const char *event); 1090 1091static inline void *event_file_data(struct file *filp) 1092{ 1093 return ACCESS_ONCE(file_inode(filp)->i_private); 1094} 1095 1096extern struct mutex event_mutex; 1097extern struct list_head ftrace_events; 1098 1099extern const struct file_operations event_trigger_fops; 1100 1101extern int register_trigger_cmds(void); 1102extern void clear_event_triggers(struct trace_array *tr); 1103 1104struct event_trigger_data { 1105 unsigned long count; 1106 int ref; 1107 struct event_trigger_ops *ops; 1108 struct event_command *cmd_ops; 1109 struct event_filter __rcu *filter; 1110 char *filter_str; 1111 void *private_data; 1112 struct list_head list; 1113}; 1114 1115/** 1116 * struct event_trigger_ops - callbacks for trace event triggers 1117 * 1118 * The methods in this structure provide per-event trigger hooks for 1119 * various trigger operations. 1120 * 1121 * All the methods below, except for @init() and @free(), must be 1122 * implemented. 1123 * 1124 * @func: The trigger 'probe' function called when the triggering 1125 * event occurs. The data passed into this callback is the data 1126 * that was supplied to the event_command @reg() function that 1127 * registered the trigger (see struct event_command). 1128 * 1129 * @init: An optional initialization function called for the trigger 1130 * when the trigger is registered (via the event_command reg() 1131 * function). This can be used to perform per-trigger 1132 * initialization such as incrementing a per-trigger reference 1133 * count, for instance. This is usually implemented by the 1134 * generic utility function @event_trigger_init() (see 1135 * trace_event_triggers.c). 1136 * 1137 * @free: An optional de-initialization function called for the 1138 * trigger when the trigger is unregistered (via the 1139 * event_command @reg() function). This can be used to perform 1140 * per-trigger de-initialization such as decrementing a 1141 * per-trigger reference count and freeing corresponding trigger 1142 * data, for instance. This is usually implemented by the 1143 * generic utility function @event_trigger_free() (see 1144 * trace_event_triggers.c). 1145 * 1146 * @print: The callback function invoked to have the trigger print 1147 * itself. This is usually implemented by a wrapper function 1148 * that calls the generic utility function @event_trigger_print() 1149 * (see trace_event_triggers.c). 1150 */ 1151struct event_trigger_ops { 1152 void (*func)(struct event_trigger_data *data); 1153 int (*init)(struct event_trigger_ops *ops, 1154 struct event_trigger_data *data); 1155 void (*free)(struct event_trigger_ops *ops, 1156 struct event_trigger_data *data); 1157 int (*print)(struct seq_file *m, 1158 struct event_trigger_ops *ops, 1159 struct event_trigger_data *data); 1160}; 1161 1162/** 1163 * struct event_command - callbacks and data members for event commands 1164 * 1165 * Event commands are invoked by users by writing the command name 1166 * into the 'trigger' file associated with a trace event. The 1167 * parameters associated with a specific invocation of an event 1168 * command are used to create an event trigger instance, which is 1169 * added to the list of trigger instances associated with that trace 1170 * event. When the event is hit, the set of triggers associated with 1171 * that event is invoked. 1172 * 1173 * The data members in this structure provide per-event command data 1174 * for various event commands. 1175 * 1176 * All the data members below, except for @post_trigger, must be set 1177 * for each event command. 1178 * 1179 * @name: The unique name that identifies the event command. This is 1180 * the name used when setting triggers via trigger files. 1181 * 1182 * @trigger_type: A unique id that identifies the event command 1183 * 'type'. This value has two purposes, the first to ensure that 1184 * only one trigger of the same type can be set at a given time 1185 * for a particular event e.g. it doesn't make sense to have both 1186 * a traceon and traceoff trigger attached to a single event at 1187 * the same time, so traceon and traceoff have the same type 1188 * though they have different names. The @trigger_type value is 1189 * also used as a bit value for deferring the actual trigger 1190 * action until after the current event is finished. Some 1191 * commands need to do this if they themselves log to the trace 1192 * buffer (see the @post_trigger() member below). @trigger_type 1193 * values are defined by adding new values to the trigger_type 1194 * enum in include/linux/ftrace_event.h. 1195 * 1196 * @post_trigger: A flag that says whether or not this command needs 1197 * to have its action delayed until after the current event has 1198 * been closed. Some triggers need to avoid being invoked while 1199 * an event is currently in the process of being logged, since 1200 * the trigger may itself log data into the trace buffer. Thus 1201 * we make sure the current event is committed before invoking 1202 * those triggers. To do that, the trigger invocation is split 1203 * in two - the first part checks the filter using the current 1204 * trace record; if a command has the @post_trigger flag set, it 1205 * sets a bit for itself in the return value, otherwise it 1206 * directly invokes the trigger. Once all commands have been 1207 * either invoked or set their return flag, the current record is 1208 * either committed or discarded. At that point, if any commands 1209 * have deferred their triggers, those commands are finally 1210 * invoked following the close of the current event. In other 1211 * words, if the event_trigger_ops @func() probe implementation 1212 * itself logs to the trace buffer, this flag should be set, 1213 * otherwise it can be left unspecified. 1214 * 1215 * All the methods below, except for @set_filter(), must be 1216 * implemented. 1217 * 1218 * @func: The callback function responsible for parsing and 1219 * registering the trigger written to the 'trigger' file by the 1220 * user. It allocates the trigger instance and registers it with 1221 * the appropriate trace event. It makes use of the other 1222 * event_command callback functions to orchestrate this, and is 1223 * usually implemented by the generic utility function 1224 * @event_trigger_callback() (see trace_event_triggers.c). 1225 * 1226 * @reg: Adds the trigger to the list of triggers associated with the 1227 * event, and enables the event trigger itself, after 1228 * initializing it (via the event_trigger_ops @init() function). 1229 * This is also where commands can use the @trigger_type value to 1230 * make the decision as to whether or not multiple instances of 1231 * the trigger should be allowed. This is usually implemented by 1232 * the generic utility function @register_trigger() (see 1233 * trace_event_triggers.c). 1234 * 1235 * @unreg: Removes the trigger from the list of triggers associated 1236 * with the event, and disables the event trigger itself, after 1237 * initializing it (via the event_trigger_ops @free() function). 1238 * This is usually implemented by the generic utility function 1239 * @unregister_trigger() (see trace_event_triggers.c). 1240 * 1241 * @set_filter: An optional function called to parse and set a filter 1242 * for the trigger. If no @set_filter() method is set for the 1243 * event command, filters set by the user for the command will be 1244 * ignored. This is usually implemented by the generic utility 1245 * function @set_trigger_filter() (see trace_event_triggers.c). 1246 * 1247 * @get_trigger_ops: The callback function invoked to retrieve the 1248 * event_trigger_ops implementation associated with the command. 1249 */ 1250struct event_command { 1251 struct list_head list; 1252 char *name; 1253 enum event_trigger_type trigger_type; 1254 bool post_trigger; 1255 int (*func)(struct event_command *cmd_ops, 1256 struct ftrace_event_file *file, 1257 char *glob, char *cmd, char *params); 1258 int (*reg)(char *glob, 1259 struct event_trigger_ops *ops, 1260 struct event_trigger_data *data, 1261 struct ftrace_event_file *file); 1262 void (*unreg)(char *glob, 1263 struct event_trigger_ops *ops, 1264 struct event_trigger_data *data, 1265 struct ftrace_event_file *file); 1266 int (*set_filter)(char *filter_str, 1267 struct event_trigger_data *data, 1268 struct ftrace_event_file *file); 1269 struct event_trigger_ops *(*get_trigger_ops)(char *cmd, char *param); 1270}; 1271 1272extern int trace_event_enable_disable(struct ftrace_event_file *file, 1273 int enable, int soft_disable); 1274extern int tracing_alloc_snapshot(void); 1275 1276extern const char *__start___trace_bprintk_fmt[]; 1277extern const char *__stop___trace_bprintk_fmt[]; 1278 1279extern const char *__start___tracepoint_str[]; 1280extern const char *__stop___tracepoint_str[]; 1281 1282void trace_printk_init_buffers(void); 1283void trace_printk_start_comm(void); 1284int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set); 1285int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled); 1286 1287/* 1288 * Normal trace_printk() and friends allocates special buffers 1289 * to do the manipulation, as well as saves the print formats 1290 * into sections to display. But the trace infrastructure wants 1291 * to use these without the added overhead at the price of being 1292 * a bit slower (used mainly for warnings, where we don't care 1293 * about performance). The internal_trace_puts() is for such 1294 * a purpose. 1295 */ 1296#define internal_trace_puts(str) __trace_puts(_THIS_IP_, str, strlen(str)) 1297 1298#undef FTRACE_ENTRY 1299#define FTRACE_ENTRY(call, struct_name, id, tstruct, print, filter) \ 1300 extern struct ftrace_event_call \ 1301 __aligned(4) event_##call; 1302#undef FTRACE_ENTRY_DUP 1303#define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print, filter) \ 1304 FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print), \ 1305 filter) 1306#include "trace_entries.h" 1307 1308#if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER) 1309int perf_ftrace_event_register(struct ftrace_event_call *call, 1310 enum trace_reg type, void *data); 1311#else 1312#define perf_ftrace_event_register NULL 1313#endif 1314 1315#endif /* _LINUX_KERNEL_TRACE_H */ 1316