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/trace_events.h> 16 #include <linux/compiler.h> 17 #include <linux/trace_seq.h> 18 19 #ifdef CONFIG_FTRACE_SYSCALLS 20 #include <asm/unistd.h> /* For NR_SYSCALLS */ 21 #include <asm/syscall.h> /* some archs define it here */ 22 #endif 23 24 enum trace_type { 25 __TRACE_FIRST_TYPE = 0, 26 27 TRACE_FN, 28 TRACE_CTX, 29 TRACE_WAKE, 30 TRACE_STACK, 31 TRACE_PRINT, 32 TRACE_BPRINT, 33 TRACE_MMIO_RW, 34 TRACE_MMIO_MAP, 35 TRACE_BRANCH, 36 TRACE_GRAPH_RET, 37 TRACE_GRAPH_ENT, 38 TRACE_USER_STACK, 39 TRACE_BLK, 40 TRACE_BPUTS, 41 42 __TRACE_LAST_TYPE, 43 }; 44 45 46 #undef __field 47 #define __field(type, item) type item; 48 49 #undef __field_struct 50 #define __field_struct(type, item) __field(type, item) 51 52 #undef __field_desc 53 #define __field_desc(type, container, item) 54 55 #undef __array 56 #define __array(type, item, size) type item[size]; 57 58 #undef __array_desc 59 #define __array_desc(type, container, item, size) 60 61 #undef __dynamic_array 62 #define __dynamic_array(type, item) type item[]; 63 64 #undef F_STRUCT 65 #define F_STRUCT(args...) args 66 67 #undef FTRACE_ENTRY 68 #define FTRACE_ENTRY(name, struct_name, id, tstruct, print, filter) \ 69 struct struct_name { \ 70 struct trace_entry ent; \ 71 tstruct \ 72 } 73 74 #undef FTRACE_ENTRY_DUP 75 #define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk, filter) 76 77 #undef FTRACE_ENTRY_REG 78 #define FTRACE_ENTRY_REG(name, struct_name, id, tstruct, print, \ 79 filter, regfn) \ 80 FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print), \ 81 filter) 82 83 #include "trace_entries.h" 84 85 /* 86 * syscalls are special, and need special handling, this is why 87 * they are not included in trace_entries.h 88 */ 89 struct syscall_trace_enter { 90 struct trace_entry ent; 91 int nr; 92 unsigned long args[]; 93 }; 94 95 struct syscall_trace_exit { 96 struct trace_entry ent; 97 int nr; 98 long ret; 99 }; 100 101 struct kprobe_trace_entry_head { 102 struct trace_entry ent; 103 unsigned long ip; 104 }; 105 106 struct kretprobe_trace_entry_head { 107 struct trace_entry ent; 108 unsigned long func; 109 unsigned long ret_ip; 110 }; 111 112 /* 113 * trace_flag_type is an enumeration that holds different 114 * states when a trace occurs. These are: 115 * IRQS_OFF - interrupts were disabled 116 * IRQS_NOSUPPORT - arch does not support irqs_disabled_flags 117 * NEED_RESCHED - reschedule is requested 118 * HARDIRQ - inside an interrupt handler 119 * SOFTIRQ - inside a softirq handler 120 */ 121 enum trace_flag_type { 122 TRACE_FLAG_IRQS_OFF = 0x01, 123 TRACE_FLAG_IRQS_NOSUPPORT = 0x02, 124 TRACE_FLAG_NEED_RESCHED = 0x04, 125 TRACE_FLAG_HARDIRQ = 0x08, 126 TRACE_FLAG_SOFTIRQ = 0x10, 127 TRACE_FLAG_PREEMPT_RESCHED = 0x20, 128 TRACE_FLAG_NMI = 0x40, 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 bool ignore_pid; 159 #ifdef CONFIG_FUNCTION_TRACER 160 bool ftrace_ignore_pid; 161 #endif 162 }; 163 164 struct tracer; 165 struct trace_option_dentry; 166 167 struct trace_buffer { 168 struct trace_array *tr; 169 struct ring_buffer *buffer; 170 struct trace_array_cpu __percpu *data; 171 cycle_t time_start; 172 int cpu; 173 }; 174 175 #define TRACE_FLAGS_MAX_SIZE 32 176 177 struct trace_options { 178 struct tracer *tracer; 179 struct trace_option_dentry *topts; 180 }; 181 182 struct trace_pid_list { 183 int pid_max; 184 unsigned long *pids; 185 }; 186 187 /* 188 * The trace array - an array of per-CPU trace arrays. This is the 189 * highest level data structure that individual tracers deal with. 190 * They have on/off state as well: 191 */ 192 struct trace_array { 193 struct list_head list; 194 char *name; 195 struct trace_buffer trace_buffer; 196 #ifdef CONFIG_TRACER_MAX_TRACE 197 /* 198 * The max_buffer is used to snapshot the trace when a maximum 199 * latency is reached, or when the user initiates a snapshot. 200 * Some tracers will use this to store a maximum trace while 201 * it continues examining live traces. 202 * 203 * The buffers for the max_buffer are set up the same as the trace_buffer 204 * When a snapshot is taken, the buffer of the max_buffer is swapped 205 * with the buffer of the trace_buffer and the buffers are reset for 206 * the trace_buffer so the tracing can continue. 207 */ 208 struct trace_buffer max_buffer; 209 bool allocated_snapshot; 210 unsigned long max_latency; 211 #endif 212 struct trace_pid_list __rcu *filtered_pids; 213 /* 214 * max_lock is used to protect the swapping of buffers 215 * when taking a max snapshot. The buffers themselves are 216 * protected by per_cpu spinlocks. But the action of the swap 217 * needs its own lock. 218 * 219 * This is defined as a arch_spinlock_t in order to help 220 * with performance when lockdep debugging is enabled. 221 * 222 * It is also used in other places outside the update_max_tr 223 * so it needs to be defined outside of the 224 * CONFIG_TRACER_MAX_TRACE. 225 */ 226 arch_spinlock_t max_lock; 227 int buffer_disabled; 228 #ifdef CONFIG_FTRACE_SYSCALLS 229 int sys_refcount_enter; 230 int sys_refcount_exit; 231 struct trace_event_file __rcu *enter_syscall_files[NR_syscalls]; 232 struct trace_event_file __rcu *exit_syscall_files[NR_syscalls]; 233 #endif 234 int stop_count; 235 int clock_id; 236 int nr_topts; 237 struct tracer *current_trace; 238 unsigned int trace_flags; 239 unsigned char trace_flags_index[TRACE_FLAGS_MAX_SIZE]; 240 unsigned int flags; 241 raw_spinlock_t start_lock; 242 struct dentry *dir; 243 struct dentry *options; 244 struct dentry *percpu_dir; 245 struct dentry *event_dir; 246 struct trace_options *topts; 247 struct list_head systems; 248 struct list_head events; 249 cpumask_var_t tracing_cpumask; /* only trace on set CPUs */ 250 int ref; 251 #ifdef CONFIG_FUNCTION_TRACER 252 struct ftrace_ops *ops; 253 struct trace_pid_list __rcu *function_pids; 254 /* function tracing enabled */ 255 int function_enabled; 256 #endif 257 }; 258 259 enum { 260 TRACE_ARRAY_FL_GLOBAL = (1 << 0) 261 }; 262 263 extern struct list_head ftrace_trace_arrays; 264 265 extern struct mutex trace_types_lock; 266 267 extern int trace_array_get(struct trace_array *tr); 268 extern void trace_array_put(struct trace_array *tr); 269 270 /* 271 * The global tracer (top) should be the first trace array added, 272 * but we check the flag anyway. 273 */ 274 static inline struct trace_array *top_trace_array(void) 275 { 276 struct trace_array *tr; 277 278 if (list_empty(&ftrace_trace_arrays)) 279 return NULL; 280 281 tr = list_entry(ftrace_trace_arrays.prev, 282 typeof(*tr), list); 283 WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL)); 284 return tr; 285 } 286 287 #define FTRACE_CMP_TYPE(var, type) \ 288 __builtin_types_compatible_p(typeof(var), type *) 289 290 #undef IF_ASSIGN 291 #define IF_ASSIGN(var, entry, etype, id) \ 292 if (FTRACE_CMP_TYPE(var, etype)) { \ 293 var = (typeof(var))(entry); \ 294 WARN_ON(id && (entry)->type != id); \ 295 break; \ 296 } 297 298 /* Will cause compile errors if type is not found. */ 299 extern void __ftrace_bad_type(void); 300 301 /* 302 * The trace_assign_type is a verifier that the entry type is 303 * the same as the type being assigned. To add new types simply 304 * add a line with the following format: 305 * 306 * IF_ASSIGN(var, ent, type, id); 307 * 308 * Where "type" is the trace type that includes the trace_entry 309 * as the "ent" item. And "id" is the trace identifier that is 310 * used in the trace_type enum. 311 * 312 * If the type can have more than one id, then use zero. 313 */ 314 #define trace_assign_type(var, ent) \ 315 do { \ 316 IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN); \ 317 IF_ASSIGN(var, ent, struct ctx_switch_entry, 0); \ 318 IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK); \ 319 IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\ 320 IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT); \ 321 IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT); \ 322 IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS); \ 323 IF_ASSIGN(var, ent, struct trace_mmiotrace_rw, \ 324 TRACE_MMIO_RW); \ 325 IF_ASSIGN(var, ent, struct trace_mmiotrace_map, \ 326 TRACE_MMIO_MAP); \ 327 IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \ 328 IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry, \ 329 TRACE_GRAPH_ENT); \ 330 IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry, \ 331 TRACE_GRAPH_RET); \ 332 __ftrace_bad_type(); \ 333 } while (0) 334 335 /* 336 * An option specific to a tracer. This is a boolean value. 337 * The bit is the bit index that sets its value on the 338 * flags value in struct tracer_flags. 339 */ 340 struct tracer_opt { 341 const char *name; /* Will appear on the trace_options file */ 342 u32 bit; /* Mask assigned in val field in tracer_flags */ 343 }; 344 345 /* 346 * The set of specific options for a tracer. Your tracer 347 * have to set the initial value of the flags val. 348 */ 349 struct tracer_flags { 350 u32 val; 351 struct tracer_opt *opts; 352 struct tracer *trace; 353 }; 354 355 /* Makes more easy to define a tracer opt */ 356 #define TRACER_OPT(s, b) .name = #s, .bit = b 357 358 359 struct trace_option_dentry { 360 struct tracer_opt *opt; 361 struct tracer_flags *flags; 362 struct trace_array *tr; 363 struct dentry *entry; 364 }; 365 366 /** 367 * struct tracer - a specific tracer and its callbacks to interact with tracefs 368 * @name: the name chosen to select it on the available_tracers file 369 * @init: called when one switches to this tracer (echo name > current_tracer) 370 * @reset: called when one switches to another tracer 371 * @start: called when tracing is unpaused (echo 1 > tracing_on) 372 * @stop: called when tracing is paused (echo 0 > tracing_on) 373 * @update_thresh: called when tracing_thresh is updated 374 * @open: called when the trace file is opened 375 * @pipe_open: called when the trace_pipe file is opened 376 * @close: called when the trace file is released 377 * @pipe_close: called when the trace_pipe file is released 378 * @read: override the default read callback on trace_pipe 379 * @splice_read: override the default splice_read callback on trace_pipe 380 * @selftest: selftest to run on boot (see trace_selftest.c) 381 * @print_headers: override the first lines that describe your columns 382 * @print_line: callback that prints a trace 383 * @set_flag: signals one of your private flags changed (trace_options file) 384 * @flags: your private flags 385 */ 386 struct tracer { 387 const char *name; 388 int (*init)(struct trace_array *tr); 389 void (*reset)(struct trace_array *tr); 390 void (*start)(struct trace_array *tr); 391 void (*stop)(struct trace_array *tr); 392 int (*update_thresh)(struct trace_array *tr); 393 void (*open)(struct trace_iterator *iter); 394 void (*pipe_open)(struct trace_iterator *iter); 395 void (*close)(struct trace_iterator *iter); 396 void (*pipe_close)(struct trace_iterator *iter); 397 ssize_t (*read)(struct trace_iterator *iter, 398 struct file *filp, char __user *ubuf, 399 size_t cnt, loff_t *ppos); 400 ssize_t (*splice_read)(struct trace_iterator *iter, 401 struct file *filp, 402 loff_t *ppos, 403 struct pipe_inode_info *pipe, 404 size_t len, 405 unsigned int flags); 406 #ifdef CONFIG_FTRACE_STARTUP_TEST 407 int (*selftest)(struct tracer *trace, 408 struct trace_array *tr); 409 #endif 410 void (*print_header)(struct seq_file *m); 411 enum print_line_t (*print_line)(struct trace_iterator *iter); 412 /* If you handled the flag setting, return 0 */ 413 int (*set_flag)(struct trace_array *tr, 414 u32 old_flags, u32 bit, int set); 415 /* Return 0 if OK with change, else return non-zero */ 416 int (*flag_changed)(struct trace_array *tr, 417 u32 mask, int set); 418 struct tracer *next; 419 struct tracer_flags *flags; 420 int enabled; 421 int ref; 422 bool print_max; 423 bool allow_instances; 424 #ifdef CONFIG_TRACER_MAX_TRACE 425 bool use_max_tr; 426 #endif 427 }; 428 429 430 /* Only current can touch trace_recursion */ 431 432 /* 433 * For function tracing recursion: 434 * The order of these bits are important. 435 * 436 * When function tracing occurs, the following steps are made: 437 * If arch does not support a ftrace feature: 438 * call internal function (uses INTERNAL bits) which calls... 439 * If callback is registered to the "global" list, the list 440 * function is called and recursion checks the GLOBAL bits. 441 * then this function calls... 442 * The function callback, which can use the FTRACE bits to 443 * check for recursion. 444 * 445 * Now if the arch does not suppport a feature, and it calls 446 * the global list function which calls the ftrace callback 447 * all three of these steps will do a recursion protection. 448 * There's no reason to do one if the previous caller already 449 * did. The recursion that we are protecting against will 450 * go through the same steps again. 451 * 452 * To prevent the multiple recursion checks, if a recursion 453 * bit is set that is higher than the MAX bit of the current 454 * check, then we know that the check was made by the previous 455 * caller, and we can skip the current check. 456 */ 457 enum { 458 TRACE_BUFFER_BIT, 459 TRACE_BUFFER_NMI_BIT, 460 TRACE_BUFFER_IRQ_BIT, 461 TRACE_BUFFER_SIRQ_BIT, 462 463 /* Start of function recursion bits */ 464 TRACE_FTRACE_BIT, 465 TRACE_FTRACE_NMI_BIT, 466 TRACE_FTRACE_IRQ_BIT, 467 TRACE_FTRACE_SIRQ_BIT, 468 469 /* INTERNAL_BITs must be greater than FTRACE_BITs */ 470 TRACE_INTERNAL_BIT, 471 TRACE_INTERNAL_NMI_BIT, 472 TRACE_INTERNAL_IRQ_BIT, 473 TRACE_INTERNAL_SIRQ_BIT, 474 475 TRACE_BRANCH_BIT, 476 /* 477 * Abuse of the trace_recursion. 478 * As we need a way to maintain state if we are tracing the function 479 * graph in irq because we want to trace a particular function that 480 * was called in irq context but we have irq tracing off. Since this 481 * can only be modified by current, we can reuse trace_recursion. 482 */ 483 TRACE_IRQ_BIT, 484 }; 485 486 #define trace_recursion_set(bit) do { (current)->trace_recursion |= (1<<(bit)); } while (0) 487 #define trace_recursion_clear(bit) do { (current)->trace_recursion &= ~(1<<(bit)); } while (0) 488 #define trace_recursion_test(bit) ((current)->trace_recursion & (1<<(bit))) 489 490 #define TRACE_CONTEXT_BITS 4 491 492 #define TRACE_FTRACE_START TRACE_FTRACE_BIT 493 #define TRACE_FTRACE_MAX ((1 << (TRACE_FTRACE_START + TRACE_CONTEXT_BITS)) - 1) 494 495 #define TRACE_LIST_START TRACE_INTERNAL_BIT 496 #define TRACE_LIST_MAX ((1 << (TRACE_LIST_START + TRACE_CONTEXT_BITS)) - 1) 497 498 #define TRACE_CONTEXT_MASK TRACE_LIST_MAX 499 500 static __always_inline int trace_get_context_bit(void) 501 { 502 int bit; 503 504 if (in_interrupt()) { 505 if (in_nmi()) 506 bit = 0; 507 508 else if (in_irq()) 509 bit = 1; 510 else 511 bit = 2; 512 } else 513 bit = 3; 514 515 return bit; 516 } 517 518 static __always_inline int trace_test_and_set_recursion(int start, int max) 519 { 520 unsigned int val = current->trace_recursion; 521 int bit; 522 523 /* A previous recursion check was made */ 524 if ((val & TRACE_CONTEXT_MASK) > max) 525 return 0; 526 527 bit = trace_get_context_bit() + start; 528 if (unlikely(val & (1 << bit))) 529 return -1; 530 531 val |= 1 << bit; 532 current->trace_recursion = val; 533 barrier(); 534 535 return bit; 536 } 537 538 static __always_inline void trace_clear_recursion(int bit) 539 { 540 unsigned int val = current->trace_recursion; 541 542 if (!bit) 543 return; 544 545 bit = 1 << bit; 546 val &= ~bit; 547 548 barrier(); 549 current->trace_recursion = val; 550 } 551 552 static inline struct ring_buffer_iter * 553 trace_buffer_iter(struct trace_iterator *iter, int cpu) 554 { 555 if (iter->buffer_iter && iter->buffer_iter[cpu]) 556 return iter->buffer_iter[cpu]; 557 return NULL; 558 } 559 560 int tracer_init(struct tracer *t, struct trace_array *tr); 561 int tracing_is_enabled(void); 562 void tracing_reset(struct trace_buffer *buf, int cpu); 563 void tracing_reset_online_cpus(struct trace_buffer *buf); 564 void tracing_reset_current(int cpu); 565 void tracing_reset_all_online_cpus(void); 566 int tracing_open_generic(struct inode *inode, struct file *filp); 567 bool tracing_is_disabled(void); 568 struct dentry *trace_create_file(const char *name, 569 umode_t mode, 570 struct dentry *parent, 571 void *data, 572 const struct file_operations *fops); 573 574 struct dentry *tracing_init_dentry(void); 575 576 struct ring_buffer_event; 577 578 struct ring_buffer_event * 579 trace_buffer_lock_reserve(struct ring_buffer *buffer, 580 int type, 581 unsigned long len, 582 unsigned long flags, 583 int pc); 584 585 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr, 586 struct trace_array_cpu *data); 587 588 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, 589 int *ent_cpu, u64 *ent_ts); 590 591 void __buffer_unlock_commit(struct ring_buffer *buffer, 592 struct ring_buffer_event *event); 593 594 int trace_empty(struct trace_iterator *iter); 595 596 void *trace_find_next_entry_inc(struct trace_iterator *iter); 597 598 void trace_init_global_iter(struct trace_iterator *iter); 599 600 void tracing_iter_reset(struct trace_iterator *iter, int cpu); 601 602 void trace_function(struct trace_array *tr, 603 unsigned long ip, 604 unsigned long parent_ip, 605 unsigned long flags, int pc); 606 void trace_graph_function(struct trace_array *tr, 607 unsigned long ip, 608 unsigned long parent_ip, 609 unsigned long flags, int pc); 610 void trace_latency_header(struct seq_file *m); 611 void trace_default_header(struct seq_file *m); 612 void print_trace_header(struct seq_file *m, struct trace_iterator *iter); 613 int trace_empty(struct trace_iterator *iter); 614 615 void trace_graph_return(struct ftrace_graph_ret *trace); 616 int trace_graph_entry(struct ftrace_graph_ent *trace); 617 void set_graph_array(struct trace_array *tr); 618 619 void tracing_start_cmdline_record(void); 620 void tracing_stop_cmdline_record(void); 621 int register_tracer(struct tracer *type); 622 int is_tracing_stopped(void); 623 624 loff_t tracing_lseek(struct file *file, loff_t offset, int whence); 625 626 extern cpumask_var_t __read_mostly tracing_buffer_mask; 627 628 #define for_each_tracing_cpu(cpu) \ 629 for_each_cpu(cpu, tracing_buffer_mask) 630 631 extern unsigned long nsecs_to_usecs(unsigned long nsecs); 632 633 extern unsigned long tracing_thresh; 634 635 /* PID filtering */ 636 637 extern int pid_max; 638 639 bool trace_find_filtered_pid(struct trace_pid_list *filtered_pids, 640 pid_t search_pid); 641 bool trace_ignore_this_task(struct trace_pid_list *filtered_pids, 642 struct task_struct *task); 643 void trace_filter_add_remove_task(struct trace_pid_list *pid_list, 644 struct task_struct *self, 645 struct task_struct *task); 646 void *trace_pid_next(struct trace_pid_list *pid_list, void *v, loff_t *pos); 647 void *trace_pid_start(struct trace_pid_list *pid_list, loff_t *pos); 648 int trace_pid_show(struct seq_file *m, void *v); 649 void trace_free_pid_list(struct trace_pid_list *pid_list); 650 int trace_pid_write(struct trace_pid_list *filtered_pids, 651 struct trace_pid_list **new_pid_list, 652 const char __user *ubuf, size_t cnt); 653 654 #ifdef CONFIG_TRACER_MAX_TRACE 655 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu); 656 void update_max_tr_single(struct trace_array *tr, 657 struct task_struct *tsk, int cpu); 658 #endif /* CONFIG_TRACER_MAX_TRACE */ 659 660 #ifdef CONFIG_STACKTRACE 661 void ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, 662 int pc); 663 664 void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, 665 int pc); 666 #else 667 static inline void ftrace_trace_userstack(struct ring_buffer *buffer, 668 unsigned long flags, int pc) 669 { 670 } 671 672 static inline void __trace_stack(struct trace_array *tr, unsigned long flags, 673 int skip, int pc) 674 { 675 } 676 #endif /* CONFIG_STACKTRACE */ 677 678 extern cycle_t ftrace_now(int cpu); 679 680 extern void trace_find_cmdline(int pid, char comm[]); 681 extern void trace_event_follow_fork(struct trace_array *tr, bool enable); 682 683 #ifdef CONFIG_DYNAMIC_FTRACE 684 extern unsigned long ftrace_update_tot_cnt; 685 #endif 686 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func 687 extern int DYN_FTRACE_TEST_NAME(void); 688 #define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2 689 extern int DYN_FTRACE_TEST_NAME2(void); 690 691 extern bool ring_buffer_expanded; 692 extern bool tracing_selftest_disabled; 693 694 #ifdef CONFIG_FTRACE_STARTUP_TEST 695 extern int trace_selftest_startup_function(struct tracer *trace, 696 struct trace_array *tr); 697 extern int trace_selftest_startup_function_graph(struct tracer *trace, 698 struct trace_array *tr); 699 extern int trace_selftest_startup_irqsoff(struct tracer *trace, 700 struct trace_array *tr); 701 extern int trace_selftest_startup_preemptoff(struct tracer *trace, 702 struct trace_array *tr); 703 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace, 704 struct trace_array *tr); 705 extern int trace_selftest_startup_wakeup(struct tracer *trace, 706 struct trace_array *tr); 707 extern int trace_selftest_startup_nop(struct tracer *trace, 708 struct trace_array *tr); 709 extern int trace_selftest_startup_sched_switch(struct tracer *trace, 710 struct trace_array *tr); 711 extern int trace_selftest_startup_branch(struct tracer *trace, 712 struct trace_array *tr); 713 /* 714 * Tracer data references selftest functions that only occur 715 * on boot up. These can be __init functions. Thus, when selftests 716 * are enabled, then the tracers need to reference __init functions. 717 */ 718 #define __tracer_data __refdata 719 #else 720 /* Tracers are seldom changed. Optimize when selftests are disabled. */ 721 #define __tracer_data __read_mostly 722 #endif /* CONFIG_FTRACE_STARTUP_TEST */ 723 724 extern void *head_page(struct trace_array_cpu *data); 725 extern unsigned long long ns2usecs(cycle_t nsec); 726 extern int 727 trace_vbprintk(unsigned long ip, const char *fmt, va_list args); 728 extern int 729 trace_vprintk(unsigned long ip, const char *fmt, va_list args); 730 extern int 731 trace_array_vprintk(struct trace_array *tr, 732 unsigned long ip, const char *fmt, va_list args); 733 int trace_array_printk(struct trace_array *tr, 734 unsigned long ip, const char *fmt, ...); 735 int trace_array_printk_buf(struct ring_buffer *buffer, 736 unsigned long ip, const char *fmt, ...); 737 void trace_printk_seq(struct trace_seq *s); 738 enum print_line_t print_trace_line(struct trace_iterator *iter); 739 740 extern char trace_find_mark(unsigned long long duration); 741 742 /* Standard output formatting function used for function return traces */ 743 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 744 745 /* Flag options */ 746 #define TRACE_GRAPH_PRINT_OVERRUN 0x1 747 #define TRACE_GRAPH_PRINT_CPU 0x2 748 #define TRACE_GRAPH_PRINT_OVERHEAD 0x4 749 #define TRACE_GRAPH_PRINT_PROC 0x8 750 #define TRACE_GRAPH_PRINT_DURATION 0x10 751 #define TRACE_GRAPH_PRINT_ABS_TIME 0x20 752 #define TRACE_GRAPH_PRINT_IRQS 0x40 753 #define TRACE_GRAPH_PRINT_TAIL 0x80 754 #define TRACE_GRAPH_SLEEP_TIME 0x100 755 #define TRACE_GRAPH_GRAPH_TIME 0x200 756 #define TRACE_GRAPH_PRINT_FILL_SHIFT 28 757 #define TRACE_GRAPH_PRINT_FILL_MASK (0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT) 758 759 extern void ftrace_graph_sleep_time_control(bool enable); 760 extern void ftrace_graph_graph_time_control(bool enable); 761 762 extern enum print_line_t 763 print_graph_function_flags(struct trace_iterator *iter, u32 flags); 764 extern void print_graph_headers_flags(struct seq_file *s, u32 flags); 765 extern void 766 trace_print_graph_duration(unsigned long long duration, struct trace_seq *s); 767 extern void graph_trace_open(struct trace_iterator *iter); 768 extern void graph_trace_close(struct trace_iterator *iter); 769 extern int __trace_graph_entry(struct trace_array *tr, 770 struct ftrace_graph_ent *trace, 771 unsigned long flags, int pc); 772 extern void __trace_graph_return(struct trace_array *tr, 773 struct ftrace_graph_ret *trace, 774 unsigned long flags, int pc); 775 776 777 #ifdef CONFIG_DYNAMIC_FTRACE 778 /* TODO: make this variable */ 779 #define FTRACE_GRAPH_MAX_FUNCS 32 780 extern int ftrace_graph_count; 781 extern unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS]; 782 extern int ftrace_graph_notrace_count; 783 extern unsigned long ftrace_graph_notrace_funcs[FTRACE_GRAPH_MAX_FUNCS]; 784 785 static inline int ftrace_graph_addr(unsigned long addr) 786 { 787 int i; 788 789 if (!ftrace_graph_count) 790 return 1; 791 792 for (i = 0; i < ftrace_graph_count; i++) { 793 if (addr == ftrace_graph_funcs[i]) { 794 /* 795 * If no irqs are to be traced, but a set_graph_function 796 * is set, and called by an interrupt handler, we still 797 * want to trace it. 798 */ 799 if (in_irq()) 800 trace_recursion_set(TRACE_IRQ_BIT); 801 else 802 trace_recursion_clear(TRACE_IRQ_BIT); 803 return 1; 804 } 805 } 806 807 return 0; 808 } 809 810 static inline int ftrace_graph_notrace_addr(unsigned long addr) 811 { 812 int i; 813 814 if (!ftrace_graph_notrace_count) 815 return 0; 816 817 for (i = 0; i < ftrace_graph_notrace_count; i++) { 818 if (addr == ftrace_graph_notrace_funcs[i]) 819 return 1; 820 } 821 822 return 0; 823 } 824 #else 825 static inline int ftrace_graph_addr(unsigned long addr) 826 { 827 return 1; 828 } 829 830 static inline int ftrace_graph_notrace_addr(unsigned long addr) 831 { 832 return 0; 833 } 834 #endif /* CONFIG_DYNAMIC_FTRACE */ 835 #else /* CONFIG_FUNCTION_GRAPH_TRACER */ 836 static inline enum print_line_t 837 print_graph_function_flags(struct trace_iterator *iter, u32 flags) 838 { 839 return TRACE_TYPE_UNHANDLED; 840 } 841 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ 842 843 extern struct list_head ftrace_pids; 844 845 #ifdef CONFIG_FUNCTION_TRACER 846 extern bool ftrace_filter_param __initdata; 847 static inline int ftrace_trace_task(struct trace_array *tr) 848 { 849 return !this_cpu_read(tr->trace_buffer.data->ftrace_ignore_pid); 850 } 851 extern int ftrace_is_dead(void); 852 int ftrace_create_function_files(struct trace_array *tr, 853 struct dentry *parent); 854 void ftrace_destroy_function_files(struct trace_array *tr); 855 void ftrace_init_global_array_ops(struct trace_array *tr); 856 void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func); 857 void ftrace_reset_array_ops(struct trace_array *tr); 858 int using_ftrace_ops_list_func(void); 859 void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer); 860 #else 861 static inline int ftrace_trace_task(struct trace_array *tr) 862 { 863 return 1; 864 } 865 static inline int ftrace_is_dead(void) { return 0; } 866 static inline int 867 ftrace_create_function_files(struct trace_array *tr, 868 struct dentry *parent) 869 { 870 return 0; 871 } 872 static inline void ftrace_destroy_function_files(struct trace_array *tr) { } 873 static inline __init void 874 ftrace_init_global_array_ops(struct trace_array *tr) { } 875 static inline void ftrace_reset_array_ops(struct trace_array *tr) { } 876 static inline void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d) { } 877 /* ftace_func_t type is not defined, use macro instead of static inline */ 878 #define ftrace_init_array_ops(tr, func) do { } while (0) 879 #endif /* CONFIG_FUNCTION_TRACER */ 880 881 #if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE) 882 void ftrace_create_filter_files(struct ftrace_ops *ops, 883 struct dentry *parent); 884 void ftrace_destroy_filter_files(struct ftrace_ops *ops); 885 #else 886 /* 887 * The ops parameter passed in is usually undefined. 888 * This must be a macro. 889 */ 890 #define ftrace_create_filter_files(ops, parent) do { } while (0) 891 #define ftrace_destroy_filter_files(ops) do { } while (0) 892 #endif /* CONFIG_FUNCTION_TRACER && CONFIG_DYNAMIC_FTRACE */ 893 894 bool ftrace_event_is_function(struct trace_event_call *call); 895 896 /* 897 * struct trace_parser - servers for reading the user input separated by spaces 898 * @cont: set if the input is not complete - no final space char was found 899 * @buffer: holds the parsed user input 900 * @idx: user input length 901 * @size: buffer size 902 */ 903 struct trace_parser { 904 bool cont; 905 char *buffer; 906 unsigned idx; 907 unsigned size; 908 }; 909 910 static inline bool trace_parser_loaded(struct trace_parser *parser) 911 { 912 return (parser->idx != 0); 913 } 914 915 static inline bool trace_parser_cont(struct trace_parser *parser) 916 { 917 return parser->cont; 918 } 919 920 static inline void trace_parser_clear(struct trace_parser *parser) 921 { 922 parser->cont = false; 923 parser->idx = 0; 924 } 925 926 extern int trace_parser_get_init(struct trace_parser *parser, int size); 927 extern void trace_parser_put(struct trace_parser *parser); 928 extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf, 929 size_t cnt, loff_t *ppos); 930 931 /* 932 * Only create function graph options if function graph is configured. 933 */ 934 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 935 # define FGRAPH_FLAGS \ 936 C(DISPLAY_GRAPH, "display-graph"), 937 #else 938 # define FGRAPH_FLAGS 939 #endif 940 941 #ifdef CONFIG_BRANCH_TRACER 942 # define BRANCH_FLAGS \ 943 C(BRANCH, "branch"), 944 #else 945 # define BRANCH_FLAGS 946 #endif 947 948 #ifdef CONFIG_FUNCTION_TRACER 949 # define FUNCTION_FLAGS \ 950 C(FUNCTION, "function-trace"), 951 # define FUNCTION_DEFAULT_FLAGS TRACE_ITER_FUNCTION 952 #else 953 # define FUNCTION_FLAGS 954 # define FUNCTION_DEFAULT_FLAGS 0UL 955 #endif 956 957 #ifdef CONFIG_STACKTRACE 958 # define STACK_FLAGS \ 959 C(STACKTRACE, "stacktrace"), 960 #else 961 # define STACK_FLAGS 962 #endif 963 964 /* 965 * trace_iterator_flags is an enumeration that defines bit 966 * positions into trace_flags that controls the output. 967 * 968 * NOTE: These bits must match the trace_options array in 969 * trace.c (this macro guarantees it). 970 */ 971 #define TRACE_FLAGS \ 972 C(PRINT_PARENT, "print-parent"), \ 973 C(SYM_OFFSET, "sym-offset"), \ 974 C(SYM_ADDR, "sym-addr"), \ 975 C(VERBOSE, "verbose"), \ 976 C(RAW, "raw"), \ 977 C(HEX, "hex"), \ 978 C(BIN, "bin"), \ 979 C(BLOCK, "block"), \ 980 C(PRINTK, "trace_printk"), \ 981 C(ANNOTATE, "annotate"), \ 982 C(USERSTACKTRACE, "userstacktrace"), \ 983 C(SYM_USEROBJ, "sym-userobj"), \ 984 C(PRINTK_MSGONLY, "printk-msg-only"), \ 985 C(CONTEXT_INFO, "context-info"), /* Print pid/cpu/time */ \ 986 C(LATENCY_FMT, "latency-format"), \ 987 C(RECORD_CMD, "record-cmd"), \ 988 C(OVERWRITE, "overwrite"), \ 989 C(STOP_ON_FREE, "disable_on_free"), \ 990 C(IRQ_INFO, "irq-info"), \ 991 C(MARKERS, "markers"), \ 992 C(EVENT_FORK, "event-fork"), \ 993 FUNCTION_FLAGS \ 994 FGRAPH_FLAGS \ 995 STACK_FLAGS \ 996 BRANCH_FLAGS 997 998 /* 999 * By defining C, we can make TRACE_FLAGS a list of bit names 1000 * that will define the bits for the flag masks. 1001 */ 1002 #undef C 1003 #define C(a, b) TRACE_ITER_##a##_BIT 1004 1005 enum trace_iterator_bits { 1006 TRACE_FLAGS 1007 /* Make sure we don't go more than we have bits for */ 1008 TRACE_ITER_LAST_BIT 1009 }; 1010 1011 /* 1012 * By redefining C, we can make TRACE_FLAGS a list of masks that 1013 * use the bits as defined above. 1014 */ 1015 #undef C 1016 #define C(a, b) TRACE_ITER_##a = (1 << TRACE_ITER_##a##_BIT) 1017 1018 enum trace_iterator_flags { TRACE_FLAGS }; 1019 1020 /* 1021 * TRACE_ITER_SYM_MASK masks the options in trace_flags that 1022 * control the output of kernel symbols. 1023 */ 1024 #define TRACE_ITER_SYM_MASK \ 1025 (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR) 1026 1027 extern struct tracer nop_trace; 1028 1029 #ifdef CONFIG_BRANCH_TRACER 1030 extern int enable_branch_tracing(struct trace_array *tr); 1031 extern void disable_branch_tracing(void); 1032 static inline int trace_branch_enable(struct trace_array *tr) 1033 { 1034 if (tr->trace_flags & TRACE_ITER_BRANCH) 1035 return enable_branch_tracing(tr); 1036 return 0; 1037 } 1038 static inline void trace_branch_disable(void) 1039 { 1040 /* due to races, always disable */ 1041 disable_branch_tracing(); 1042 } 1043 #else 1044 static inline int trace_branch_enable(struct trace_array *tr) 1045 { 1046 return 0; 1047 } 1048 static inline void trace_branch_disable(void) 1049 { 1050 } 1051 #endif /* CONFIG_BRANCH_TRACER */ 1052 1053 /* set ring buffers to default size if not already done so */ 1054 int tracing_update_buffers(void); 1055 1056 struct ftrace_event_field { 1057 struct list_head link; 1058 const char *name; 1059 const char *type; 1060 int filter_type; 1061 int offset; 1062 int size; 1063 int is_signed; 1064 }; 1065 1066 struct event_filter { 1067 int n_preds; /* Number assigned */ 1068 int a_preds; /* allocated */ 1069 struct filter_pred *preds; 1070 struct filter_pred *root; 1071 char *filter_string; 1072 }; 1073 1074 struct event_subsystem { 1075 struct list_head list; 1076 const char *name; 1077 struct event_filter *filter; 1078 int ref_count; 1079 }; 1080 1081 struct trace_subsystem_dir { 1082 struct list_head list; 1083 struct event_subsystem *subsystem; 1084 struct trace_array *tr; 1085 struct dentry *entry; 1086 int ref_count; 1087 int nr_events; 1088 }; 1089 1090 extern int call_filter_check_discard(struct trace_event_call *call, void *rec, 1091 struct ring_buffer *buffer, 1092 struct ring_buffer_event *event); 1093 1094 void trace_buffer_unlock_commit_regs(struct trace_array *tr, 1095 struct ring_buffer *buffer, 1096 struct ring_buffer_event *event, 1097 unsigned long flags, int pc, 1098 struct pt_regs *regs); 1099 1100 static inline void trace_buffer_unlock_commit(struct trace_array *tr, 1101 struct ring_buffer *buffer, 1102 struct ring_buffer_event *event, 1103 unsigned long flags, int pc) 1104 { 1105 trace_buffer_unlock_commit_regs(tr, buffer, event, flags, pc, NULL); 1106 } 1107 1108 DECLARE_PER_CPU(struct ring_buffer_event *, trace_buffered_event); 1109 DECLARE_PER_CPU(int, trace_buffered_event_cnt); 1110 void trace_buffered_event_disable(void); 1111 void trace_buffered_event_enable(void); 1112 1113 static inline void 1114 __trace_event_discard_commit(struct ring_buffer *buffer, 1115 struct ring_buffer_event *event) 1116 { 1117 if (this_cpu_read(trace_buffered_event) == event) { 1118 /* Simply release the temp buffer */ 1119 this_cpu_dec(trace_buffered_event_cnt); 1120 return; 1121 } 1122 ring_buffer_discard_commit(buffer, event); 1123 } 1124 1125 /* 1126 * Helper function for event_trigger_unlock_commit{_regs}(). 1127 * If there are event triggers attached to this event that requires 1128 * filtering against its fields, then they wil be called as the 1129 * entry already holds the field information of the current event. 1130 * 1131 * It also checks if the event should be discarded or not. 1132 * It is to be discarded if the event is soft disabled and the 1133 * event was only recorded to process triggers, or if the event 1134 * filter is active and this event did not match the filters. 1135 * 1136 * Returns true if the event is discarded, false otherwise. 1137 */ 1138 static inline bool 1139 __event_trigger_test_discard(struct trace_event_file *file, 1140 struct ring_buffer *buffer, 1141 struct ring_buffer_event *event, 1142 void *entry, 1143 enum event_trigger_type *tt) 1144 { 1145 unsigned long eflags = file->flags; 1146 1147 if (eflags & EVENT_FILE_FL_TRIGGER_COND) 1148 *tt = event_triggers_call(file, entry); 1149 1150 if (test_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &file->flags) || 1151 (unlikely(file->flags & EVENT_FILE_FL_FILTERED) && 1152 !filter_match_preds(file->filter, entry))) { 1153 __trace_event_discard_commit(buffer, event); 1154 return true; 1155 } 1156 1157 return false; 1158 } 1159 1160 /** 1161 * event_trigger_unlock_commit - handle triggers and finish event commit 1162 * @file: The file pointer assoctiated to the event 1163 * @buffer: The ring buffer that the event is being written to 1164 * @event: The event meta data in the ring buffer 1165 * @entry: The event itself 1166 * @irq_flags: The state of the interrupts at the start of the event 1167 * @pc: The state of the preempt count at the start of the event. 1168 * 1169 * This is a helper function to handle triggers that require data 1170 * from the event itself. It also tests the event against filters and 1171 * if the event is soft disabled and should be discarded. 1172 */ 1173 static inline void 1174 event_trigger_unlock_commit(struct trace_event_file *file, 1175 struct ring_buffer *buffer, 1176 struct ring_buffer_event *event, 1177 void *entry, unsigned long irq_flags, int pc) 1178 { 1179 enum event_trigger_type tt = ETT_NONE; 1180 1181 if (!__event_trigger_test_discard(file, buffer, event, entry, &tt)) 1182 trace_buffer_unlock_commit(file->tr, buffer, event, irq_flags, pc); 1183 1184 if (tt) 1185 event_triggers_post_call(file, tt, entry); 1186 } 1187 1188 /** 1189 * event_trigger_unlock_commit_regs - handle triggers and finish event commit 1190 * @file: The file pointer assoctiated to the event 1191 * @buffer: The ring buffer that the event is being written to 1192 * @event: The event meta data in the ring buffer 1193 * @entry: The event itself 1194 * @irq_flags: The state of the interrupts at the start of the event 1195 * @pc: The state of the preempt count at the start of the event. 1196 * 1197 * This is a helper function to handle triggers that require data 1198 * from the event itself. It also tests the event against filters and 1199 * if the event is soft disabled and should be discarded. 1200 * 1201 * Same as event_trigger_unlock_commit() but calls 1202 * trace_buffer_unlock_commit_regs() instead of trace_buffer_unlock_commit(). 1203 */ 1204 static inline void 1205 event_trigger_unlock_commit_regs(struct trace_event_file *file, 1206 struct ring_buffer *buffer, 1207 struct ring_buffer_event *event, 1208 void *entry, unsigned long irq_flags, int pc, 1209 struct pt_regs *regs) 1210 { 1211 enum event_trigger_type tt = ETT_NONE; 1212 1213 if (!__event_trigger_test_discard(file, buffer, event, entry, &tt)) 1214 trace_buffer_unlock_commit_regs(file->tr, buffer, event, 1215 irq_flags, pc, regs); 1216 1217 if (tt) 1218 event_triggers_post_call(file, tt, entry); 1219 } 1220 1221 #define FILTER_PRED_INVALID ((unsigned short)-1) 1222 #define FILTER_PRED_IS_RIGHT (1 << 15) 1223 #define FILTER_PRED_FOLD (1 << 15) 1224 1225 /* 1226 * The max preds is the size of unsigned short with 1227 * two flags at the MSBs. One bit is used for both the IS_RIGHT 1228 * and FOLD flags. The other is reserved. 1229 * 1230 * 2^14 preds is way more than enough. 1231 */ 1232 #define MAX_FILTER_PRED 16384 1233 1234 struct filter_pred; 1235 struct regex; 1236 1237 typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event); 1238 1239 typedef int (*regex_match_func)(char *str, struct regex *r, int len); 1240 1241 enum regex_type { 1242 MATCH_FULL = 0, 1243 MATCH_FRONT_ONLY, 1244 MATCH_MIDDLE_ONLY, 1245 MATCH_END_ONLY, 1246 }; 1247 1248 struct regex { 1249 char pattern[MAX_FILTER_STR_VAL]; 1250 int len; 1251 int field_len; 1252 regex_match_func match; 1253 }; 1254 1255 struct filter_pred { 1256 filter_pred_fn_t fn; 1257 u64 val; 1258 struct regex regex; 1259 unsigned short *ops; 1260 struct ftrace_event_field *field; 1261 int offset; 1262 int not; 1263 int op; 1264 unsigned short index; 1265 unsigned short parent; 1266 unsigned short left; 1267 unsigned short right; 1268 }; 1269 1270 static inline bool is_string_field(struct ftrace_event_field *field) 1271 { 1272 return field->filter_type == FILTER_DYN_STRING || 1273 field->filter_type == FILTER_STATIC_STRING || 1274 field->filter_type == FILTER_PTR_STRING; 1275 } 1276 1277 static inline bool is_function_field(struct ftrace_event_field *field) 1278 { 1279 return field->filter_type == FILTER_TRACE_FN; 1280 } 1281 1282 extern enum regex_type 1283 filter_parse_regex(char *buff, int len, char **search, int *not); 1284 extern void print_event_filter(struct trace_event_file *file, 1285 struct trace_seq *s); 1286 extern int apply_event_filter(struct trace_event_file *file, 1287 char *filter_string); 1288 extern int apply_subsystem_event_filter(struct trace_subsystem_dir *dir, 1289 char *filter_string); 1290 extern void print_subsystem_event_filter(struct event_subsystem *system, 1291 struct trace_seq *s); 1292 extern int filter_assign_type(const char *type); 1293 extern int create_event_filter(struct trace_event_call *call, 1294 char *filter_str, bool set_str, 1295 struct event_filter **filterp); 1296 extern void free_event_filter(struct event_filter *filter); 1297 1298 struct ftrace_event_field * 1299 trace_find_event_field(struct trace_event_call *call, char *name); 1300 1301 extern void trace_event_enable_cmd_record(bool enable); 1302 extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr); 1303 extern int event_trace_del_tracer(struct trace_array *tr); 1304 1305 extern struct trace_event_file *find_event_file(struct trace_array *tr, 1306 const char *system, 1307 const char *event); 1308 1309 static inline void *event_file_data(struct file *filp) 1310 { 1311 return ACCESS_ONCE(file_inode(filp)->i_private); 1312 } 1313 1314 extern struct mutex event_mutex; 1315 extern struct list_head ftrace_events; 1316 1317 extern const struct file_operations event_trigger_fops; 1318 extern const struct file_operations event_hist_fops; 1319 1320 #ifdef CONFIG_HIST_TRIGGERS 1321 extern int register_trigger_hist_cmd(void); 1322 extern int register_trigger_hist_enable_disable_cmds(void); 1323 #else 1324 static inline int register_trigger_hist_cmd(void) { return 0; } 1325 static inline int register_trigger_hist_enable_disable_cmds(void) { return 0; } 1326 #endif 1327 1328 extern int register_trigger_cmds(void); 1329 extern void clear_event_triggers(struct trace_array *tr); 1330 1331 struct event_trigger_data { 1332 unsigned long count; 1333 int ref; 1334 struct event_trigger_ops *ops; 1335 struct event_command *cmd_ops; 1336 struct event_filter __rcu *filter; 1337 char *filter_str; 1338 void *private_data; 1339 bool paused; 1340 bool paused_tmp; 1341 struct list_head list; 1342 char *name; 1343 struct list_head named_list; 1344 struct event_trigger_data *named_data; 1345 }; 1346 1347 /* Avoid typos */ 1348 #define ENABLE_EVENT_STR "enable_event" 1349 #define DISABLE_EVENT_STR "disable_event" 1350 #define ENABLE_HIST_STR "enable_hist" 1351 #define DISABLE_HIST_STR "disable_hist" 1352 1353 struct enable_trigger_data { 1354 struct trace_event_file *file; 1355 bool enable; 1356 bool hist; 1357 }; 1358 1359 extern int event_enable_trigger_print(struct seq_file *m, 1360 struct event_trigger_ops *ops, 1361 struct event_trigger_data *data); 1362 extern void event_enable_trigger_free(struct event_trigger_ops *ops, 1363 struct event_trigger_data *data); 1364 extern int event_enable_trigger_func(struct event_command *cmd_ops, 1365 struct trace_event_file *file, 1366 char *glob, char *cmd, char *param); 1367 extern int event_enable_register_trigger(char *glob, 1368 struct event_trigger_ops *ops, 1369 struct event_trigger_data *data, 1370 struct trace_event_file *file); 1371 extern void event_enable_unregister_trigger(char *glob, 1372 struct event_trigger_ops *ops, 1373 struct event_trigger_data *test, 1374 struct trace_event_file *file); 1375 extern void trigger_data_free(struct event_trigger_data *data); 1376 extern int event_trigger_init(struct event_trigger_ops *ops, 1377 struct event_trigger_data *data); 1378 extern int trace_event_trigger_enable_disable(struct trace_event_file *file, 1379 int trigger_enable); 1380 extern void update_cond_flag(struct trace_event_file *file); 1381 extern void unregister_trigger(char *glob, struct event_trigger_ops *ops, 1382 struct event_trigger_data *test, 1383 struct trace_event_file *file); 1384 extern int set_trigger_filter(char *filter_str, 1385 struct event_trigger_data *trigger_data, 1386 struct trace_event_file *file); 1387 extern struct event_trigger_data *find_named_trigger(const char *name); 1388 extern bool is_named_trigger(struct event_trigger_data *test); 1389 extern int save_named_trigger(const char *name, 1390 struct event_trigger_data *data); 1391 extern void del_named_trigger(struct event_trigger_data *data); 1392 extern void pause_named_trigger(struct event_trigger_data *data); 1393 extern void unpause_named_trigger(struct event_trigger_data *data); 1394 extern void set_named_trigger_data(struct event_trigger_data *data, 1395 struct event_trigger_data *named_data); 1396 extern int register_event_command(struct event_command *cmd); 1397 extern int unregister_event_command(struct event_command *cmd); 1398 extern int register_trigger_hist_enable_disable_cmds(void); 1399 1400 /** 1401 * struct event_trigger_ops - callbacks for trace event triggers 1402 * 1403 * The methods in this structure provide per-event trigger hooks for 1404 * various trigger operations. 1405 * 1406 * All the methods below, except for @init() and @free(), must be 1407 * implemented. 1408 * 1409 * @func: The trigger 'probe' function called when the triggering 1410 * event occurs. The data passed into this callback is the data 1411 * that was supplied to the event_command @reg() function that 1412 * registered the trigger (see struct event_command) along with 1413 * the trace record, rec. 1414 * 1415 * @init: An optional initialization function called for the trigger 1416 * when the trigger is registered (via the event_command reg() 1417 * function). This can be used to perform per-trigger 1418 * initialization such as incrementing a per-trigger reference 1419 * count, for instance. This is usually implemented by the 1420 * generic utility function @event_trigger_init() (see 1421 * trace_event_triggers.c). 1422 * 1423 * @free: An optional de-initialization function called for the 1424 * trigger when the trigger is unregistered (via the 1425 * event_command @reg() function). This can be used to perform 1426 * per-trigger de-initialization such as decrementing a 1427 * per-trigger reference count and freeing corresponding trigger 1428 * data, for instance. This is usually implemented by the 1429 * generic utility function @event_trigger_free() (see 1430 * trace_event_triggers.c). 1431 * 1432 * @print: The callback function invoked to have the trigger print 1433 * itself. This is usually implemented by a wrapper function 1434 * that calls the generic utility function @event_trigger_print() 1435 * (see trace_event_triggers.c). 1436 */ 1437 struct event_trigger_ops { 1438 void (*func)(struct event_trigger_data *data, 1439 void *rec); 1440 int (*init)(struct event_trigger_ops *ops, 1441 struct event_trigger_data *data); 1442 void (*free)(struct event_trigger_ops *ops, 1443 struct event_trigger_data *data); 1444 int (*print)(struct seq_file *m, 1445 struct event_trigger_ops *ops, 1446 struct event_trigger_data *data); 1447 }; 1448 1449 /** 1450 * struct event_command - callbacks and data members for event commands 1451 * 1452 * Event commands are invoked by users by writing the command name 1453 * into the 'trigger' file associated with a trace event. The 1454 * parameters associated with a specific invocation of an event 1455 * command are used to create an event trigger instance, which is 1456 * added to the list of trigger instances associated with that trace 1457 * event. When the event is hit, the set of triggers associated with 1458 * that event is invoked. 1459 * 1460 * The data members in this structure provide per-event command data 1461 * for various event commands. 1462 * 1463 * All the data members below, except for @post_trigger, must be set 1464 * for each event command. 1465 * 1466 * @name: The unique name that identifies the event command. This is 1467 * the name used when setting triggers via trigger files. 1468 * 1469 * @trigger_type: A unique id that identifies the event command 1470 * 'type'. This value has two purposes, the first to ensure that 1471 * only one trigger of the same type can be set at a given time 1472 * for a particular event e.g. it doesn't make sense to have both 1473 * a traceon and traceoff trigger attached to a single event at 1474 * the same time, so traceon and traceoff have the same type 1475 * though they have different names. The @trigger_type value is 1476 * also used as a bit value for deferring the actual trigger 1477 * action until after the current event is finished. Some 1478 * commands need to do this if they themselves log to the trace 1479 * buffer (see the @post_trigger() member below). @trigger_type 1480 * values are defined by adding new values to the trigger_type 1481 * enum in include/linux/trace_events.h. 1482 * 1483 * @flags: See the enum event_command_flags below. 1484 * 1485 * All the methods below, except for @set_filter() and @unreg_all(), 1486 * must be implemented. 1487 * 1488 * @func: The callback function responsible for parsing and 1489 * registering the trigger written to the 'trigger' file by the 1490 * user. It allocates the trigger instance and registers it with 1491 * the appropriate trace event. It makes use of the other 1492 * event_command callback functions to orchestrate this, and is 1493 * usually implemented by the generic utility function 1494 * @event_trigger_callback() (see trace_event_triggers.c). 1495 * 1496 * @reg: Adds the trigger to the list of triggers associated with the 1497 * event, and enables the event trigger itself, after 1498 * initializing it (via the event_trigger_ops @init() function). 1499 * This is also where commands can use the @trigger_type value to 1500 * make the decision as to whether or not multiple instances of 1501 * the trigger should be allowed. This is usually implemented by 1502 * the generic utility function @register_trigger() (see 1503 * trace_event_triggers.c). 1504 * 1505 * @unreg: Removes the trigger from the list of triggers associated 1506 * with the event, and disables the event trigger itself, after 1507 * initializing it (via the event_trigger_ops @free() function). 1508 * This is usually implemented by the generic utility function 1509 * @unregister_trigger() (see trace_event_triggers.c). 1510 * 1511 * @unreg_all: An optional function called to remove all the triggers 1512 * from the list of triggers associated with the event. Called 1513 * when a trigger file is opened in truncate mode. 1514 * 1515 * @set_filter: An optional function called to parse and set a filter 1516 * for the trigger. If no @set_filter() method is set for the 1517 * event command, filters set by the user for the command will be 1518 * ignored. This is usually implemented by the generic utility 1519 * function @set_trigger_filter() (see trace_event_triggers.c). 1520 * 1521 * @get_trigger_ops: The callback function invoked to retrieve the 1522 * event_trigger_ops implementation associated with the command. 1523 */ 1524 struct event_command { 1525 struct list_head list; 1526 char *name; 1527 enum event_trigger_type trigger_type; 1528 int flags; 1529 int (*func)(struct event_command *cmd_ops, 1530 struct trace_event_file *file, 1531 char *glob, char *cmd, char *params); 1532 int (*reg)(char *glob, 1533 struct event_trigger_ops *ops, 1534 struct event_trigger_data *data, 1535 struct trace_event_file *file); 1536 void (*unreg)(char *glob, 1537 struct event_trigger_ops *ops, 1538 struct event_trigger_data *data, 1539 struct trace_event_file *file); 1540 void (*unreg_all)(struct trace_event_file *file); 1541 int (*set_filter)(char *filter_str, 1542 struct event_trigger_data *data, 1543 struct trace_event_file *file); 1544 struct event_trigger_ops *(*get_trigger_ops)(char *cmd, char *param); 1545 }; 1546 1547 /** 1548 * enum event_command_flags - flags for struct event_command 1549 * 1550 * @POST_TRIGGER: A flag that says whether or not this command needs 1551 * to have its action delayed until after the current event has 1552 * been closed. Some triggers need to avoid being invoked while 1553 * an event is currently in the process of being logged, since 1554 * the trigger may itself log data into the trace buffer. Thus 1555 * we make sure the current event is committed before invoking 1556 * those triggers. To do that, the trigger invocation is split 1557 * in two - the first part checks the filter using the current 1558 * trace record; if a command has the @post_trigger flag set, it 1559 * sets a bit for itself in the return value, otherwise it 1560 * directly invokes the trigger. Once all commands have been 1561 * either invoked or set their return flag, the current record is 1562 * either committed or discarded. At that point, if any commands 1563 * have deferred their triggers, those commands are finally 1564 * invoked following the close of the current event. In other 1565 * words, if the event_trigger_ops @func() probe implementation 1566 * itself logs to the trace buffer, this flag should be set, 1567 * otherwise it can be left unspecified. 1568 * 1569 * @NEEDS_REC: A flag that says whether or not this command needs 1570 * access to the trace record in order to perform its function, 1571 * regardless of whether or not it has a filter associated with 1572 * it (filters make a trigger require access to the trace record 1573 * but are not always present). 1574 */ 1575 enum event_command_flags { 1576 EVENT_CMD_FL_POST_TRIGGER = 1, 1577 EVENT_CMD_FL_NEEDS_REC = 2, 1578 }; 1579 1580 static inline bool event_command_post_trigger(struct event_command *cmd_ops) 1581 { 1582 return cmd_ops->flags & EVENT_CMD_FL_POST_TRIGGER; 1583 } 1584 1585 static inline bool event_command_needs_rec(struct event_command *cmd_ops) 1586 { 1587 return cmd_ops->flags & EVENT_CMD_FL_NEEDS_REC; 1588 } 1589 1590 extern int trace_event_enable_disable(struct trace_event_file *file, 1591 int enable, int soft_disable); 1592 extern int tracing_alloc_snapshot(void); 1593 1594 extern const char *__start___trace_bprintk_fmt[]; 1595 extern const char *__stop___trace_bprintk_fmt[]; 1596 1597 extern const char *__start___tracepoint_str[]; 1598 extern const char *__stop___tracepoint_str[]; 1599 1600 void trace_printk_control(bool enabled); 1601 void trace_printk_init_buffers(void); 1602 void trace_printk_start_comm(void); 1603 int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set); 1604 int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled); 1605 1606 /* 1607 * Normal trace_printk() and friends allocates special buffers 1608 * to do the manipulation, as well as saves the print formats 1609 * into sections to display. But the trace infrastructure wants 1610 * to use these without the added overhead at the price of being 1611 * a bit slower (used mainly for warnings, where we don't care 1612 * about performance). The internal_trace_puts() is for such 1613 * a purpose. 1614 */ 1615 #define internal_trace_puts(str) __trace_puts(_THIS_IP_, str, strlen(str)) 1616 1617 #undef FTRACE_ENTRY 1618 #define FTRACE_ENTRY(call, struct_name, id, tstruct, print, filter) \ 1619 extern struct trace_event_call \ 1620 __aligned(4) event_##call; 1621 #undef FTRACE_ENTRY_DUP 1622 #define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print, filter) \ 1623 FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print), \ 1624 filter) 1625 #include "trace_entries.h" 1626 1627 #if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER) 1628 int perf_ftrace_event_register(struct trace_event_call *call, 1629 enum trace_reg type, void *data); 1630 #else 1631 #define perf_ftrace_event_register NULL 1632 #endif 1633 1634 #ifdef CONFIG_FTRACE_SYSCALLS 1635 void init_ftrace_syscalls(void); 1636 const char *get_syscall_name(int syscall); 1637 #else 1638 static inline void init_ftrace_syscalls(void) { } 1639 static inline const char *get_syscall_name(int syscall) 1640 { 1641 return NULL; 1642 } 1643 #endif 1644 1645 #ifdef CONFIG_EVENT_TRACING 1646 void trace_event_init(void); 1647 void trace_event_enum_update(struct trace_enum_map **map, int len); 1648 #else 1649 static inline void __init trace_event_init(void) { } 1650 static inline void trace_event_enum_update(struct trace_enum_map **map, int len) { } 1651 #endif 1652 1653 extern struct trace_iterator *tracepoint_print_iter; 1654 1655 #endif /* _LINUX_KERNEL_TRACE_H */ 1656