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