1 /* SPDX-License-Identifier: GPL-2.0 */ 2 3 #ifndef _LINUX_KERNEL_TRACE_H 4 #define _LINUX_KERNEL_TRACE_H 5 6 #include <linux/fs.h> 7 #include <linux/atomic.h> 8 #include <linux/sched.h> 9 #include <linux/clocksource.h> 10 #include <linux/ring_buffer.h> 11 #include <linux/mmiotrace.h> 12 #include <linux/tracepoint.h> 13 #include <linux/ftrace.h> 14 #include <linux/hw_breakpoint.h> 15 #include <linux/trace_seq.h> 16 #include <linux/trace_events.h> 17 #include <linux/compiler.h> 18 #include <linux/trace_seq.h> 19 #include <linux/glob.h> 20 21 #ifdef CONFIG_FTRACE_SYSCALLS 22 #include <asm/unistd.h> /* For NR_SYSCALLS */ 23 #include <asm/syscall.h> /* some archs define it here */ 24 #endif 25 26 enum trace_type { 27 __TRACE_FIRST_TYPE = 0, 28 29 TRACE_FN, 30 TRACE_CTX, 31 TRACE_WAKE, 32 TRACE_STACK, 33 TRACE_PRINT, 34 TRACE_BPRINT, 35 TRACE_MMIO_RW, 36 TRACE_MMIO_MAP, 37 TRACE_BRANCH, 38 TRACE_GRAPH_RET, 39 TRACE_GRAPH_ENT, 40 TRACE_USER_STACK, 41 TRACE_BLK, 42 TRACE_BPUTS, 43 TRACE_HWLAT, 44 TRACE_RAW_DATA, 45 46 __TRACE_LAST_TYPE, 47 }; 48 49 50 #undef __field 51 #define __field(type, item) type item; 52 53 #undef __field_struct 54 #define __field_struct(type, item) __field(type, item) 55 56 #undef __field_desc 57 #define __field_desc(type, container, item) 58 59 #undef __array 60 #define __array(type, item, size) type item[size]; 61 62 #undef __array_desc 63 #define __array_desc(type, container, item, size) 64 65 #undef __dynamic_array 66 #define __dynamic_array(type, item) type item[]; 67 68 #undef F_STRUCT 69 #define F_STRUCT(args...) args 70 71 #undef FTRACE_ENTRY 72 #define FTRACE_ENTRY(name, struct_name, id, tstruct, print, filter) \ 73 struct struct_name { \ 74 struct trace_entry ent; \ 75 tstruct \ 76 } 77 78 #undef FTRACE_ENTRY_DUP 79 #define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk, filter) 80 81 #undef FTRACE_ENTRY_REG 82 #define FTRACE_ENTRY_REG(name, struct_name, id, tstruct, print, \ 83 filter, regfn) \ 84 FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print), \ 85 filter) 86 87 #undef FTRACE_ENTRY_PACKED 88 #define FTRACE_ENTRY_PACKED(name, struct_name, id, tstruct, print, \ 89 filter) \ 90 FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print), \ 91 filter) __packed 92 93 #include "trace_entries.h" 94 95 /* 96 * syscalls are special, and need special handling, this is why 97 * they are not included in trace_entries.h 98 */ 99 struct syscall_trace_enter { 100 struct trace_entry ent; 101 int nr; 102 unsigned long args[]; 103 }; 104 105 struct syscall_trace_exit { 106 struct trace_entry ent; 107 int nr; 108 long ret; 109 }; 110 111 struct kprobe_trace_entry_head { 112 struct trace_entry ent; 113 unsigned long ip; 114 }; 115 116 struct kretprobe_trace_entry_head { 117 struct trace_entry ent; 118 unsigned long func; 119 unsigned long ret_ip; 120 }; 121 122 /* 123 * trace_flag_type is an enumeration that holds different 124 * states when a trace occurs. These are: 125 * IRQS_OFF - interrupts were disabled 126 * IRQS_NOSUPPORT - arch does not support irqs_disabled_flags 127 * NEED_RESCHED - reschedule is requested 128 * HARDIRQ - inside an interrupt handler 129 * SOFTIRQ - inside a softirq handler 130 */ 131 enum trace_flag_type { 132 TRACE_FLAG_IRQS_OFF = 0x01, 133 TRACE_FLAG_IRQS_NOSUPPORT = 0x02, 134 TRACE_FLAG_NEED_RESCHED = 0x04, 135 TRACE_FLAG_HARDIRQ = 0x08, 136 TRACE_FLAG_SOFTIRQ = 0x10, 137 TRACE_FLAG_PREEMPT_RESCHED = 0x20, 138 TRACE_FLAG_NMI = 0x40, 139 }; 140 141 #define TRACE_BUF_SIZE 1024 142 143 struct trace_array; 144 145 /* 146 * The CPU trace array - it consists of thousands of trace entries 147 * plus some other descriptor data: (for example which task started 148 * the trace, etc.) 149 */ 150 struct trace_array_cpu { 151 atomic_t disabled; 152 void *buffer_page; /* ring buffer spare */ 153 154 unsigned long entries; 155 unsigned long saved_latency; 156 unsigned long critical_start; 157 unsigned long critical_end; 158 unsigned long critical_sequence; 159 unsigned long nice; 160 unsigned long policy; 161 unsigned long rt_priority; 162 unsigned long skipped_entries; 163 u64 preempt_timestamp; 164 pid_t pid; 165 kuid_t uid; 166 char comm[TASK_COMM_LEN]; 167 168 bool ignore_pid; 169 #ifdef CONFIG_FUNCTION_TRACER 170 bool ftrace_ignore_pid; 171 #endif 172 }; 173 174 struct tracer; 175 struct trace_option_dentry; 176 177 struct trace_buffer { 178 struct trace_array *tr; 179 struct ring_buffer *buffer; 180 struct trace_array_cpu __percpu *data; 181 u64 time_start; 182 int cpu; 183 }; 184 185 #define TRACE_FLAGS_MAX_SIZE 32 186 187 struct trace_options { 188 struct tracer *tracer; 189 struct trace_option_dentry *topts; 190 }; 191 192 struct trace_pid_list { 193 int pid_max; 194 unsigned long *pids; 195 }; 196 197 /* 198 * The trace array - an array of per-CPU trace arrays. This is the 199 * highest level data structure that individual tracers deal with. 200 * They have on/off state as well: 201 */ 202 struct trace_array { 203 struct list_head list; 204 char *name; 205 struct trace_buffer trace_buffer; 206 #ifdef CONFIG_TRACER_MAX_TRACE 207 /* 208 * The max_buffer is used to snapshot the trace when a maximum 209 * latency is reached, or when the user initiates a snapshot. 210 * Some tracers will use this to store a maximum trace while 211 * it continues examining live traces. 212 * 213 * The buffers for the max_buffer are set up the same as the trace_buffer 214 * When a snapshot is taken, the buffer of the max_buffer is swapped 215 * with the buffer of the trace_buffer and the buffers are reset for 216 * the trace_buffer so the tracing can continue. 217 */ 218 struct trace_buffer max_buffer; 219 bool allocated_snapshot; 220 #endif 221 #if defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER) 222 unsigned long max_latency; 223 #endif 224 struct trace_pid_list __rcu *filtered_pids; 225 /* 226 * max_lock is used to protect the swapping of buffers 227 * when taking a max snapshot. The buffers themselves are 228 * protected by per_cpu spinlocks. But the action of the swap 229 * needs its own lock. 230 * 231 * This is defined as a arch_spinlock_t in order to help 232 * with performance when lockdep debugging is enabled. 233 * 234 * It is also used in other places outside the update_max_tr 235 * so it needs to be defined outside of the 236 * CONFIG_TRACER_MAX_TRACE. 237 */ 238 arch_spinlock_t max_lock; 239 int buffer_disabled; 240 #ifdef CONFIG_FTRACE_SYSCALLS 241 int sys_refcount_enter; 242 int sys_refcount_exit; 243 struct trace_event_file __rcu *enter_syscall_files[NR_syscalls]; 244 struct trace_event_file __rcu *exit_syscall_files[NR_syscalls]; 245 #endif 246 int stop_count; 247 int clock_id; 248 int nr_topts; 249 bool clear_trace; 250 struct tracer *current_trace; 251 unsigned int trace_flags; 252 unsigned char trace_flags_index[TRACE_FLAGS_MAX_SIZE]; 253 unsigned int flags; 254 raw_spinlock_t start_lock; 255 struct dentry *dir; 256 struct dentry *options; 257 struct dentry *percpu_dir; 258 struct dentry *event_dir; 259 struct trace_options *topts; 260 struct list_head systems; 261 struct list_head events; 262 cpumask_var_t tracing_cpumask; /* only trace on set CPUs */ 263 int ref; 264 #ifdef CONFIG_FUNCTION_TRACER 265 struct ftrace_ops *ops; 266 struct trace_pid_list __rcu *function_pids; 267 #ifdef CONFIG_DYNAMIC_FTRACE 268 /* All of these are protected by the ftrace_lock */ 269 struct list_head func_probes; 270 struct list_head mod_trace; 271 struct list_head mod_notrace; 272 #endif 273 /* function tracing enabled */ 274 int function_enabled; 275 #endif 276 }; 277 278 enum { 279 TRACE_ARRAY_FL_GLOBAL = (1 << 0) 280 }; 281 282 extern struct list_head ftrace_trace_arrays; 283 284 extern struct mutex trace_types_lock; 285 286 extern int trace_array_get(struct trace_array *tr); 287 extern void trace_array_put(struct trace_array *tr); 288 289 /* 290 * The global tracer (top) should be the first trace array added, 291 * but we check the flag anyway. 292 */ 293 static inline struct trace_array *top_trace_array(void) 294 { 295 struct trace_array *tr; 296 297 if (list_empty(&ftrace_trace_arrays)) 298 return NULL; 299 300 tr = list_entry(ftrace_trace_arrays.prev, 301 typeof(*tr), list); 302 WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL)); 303 return tr; 304 } 305 306 #define FTRACE_CMP_TYPE(var, type) \ 307 __builtin_types_compatible_p(typeof(var), type *) 308 309 #undef IF_ASSIGN 310 #define IF_ASSIGN(var, entry, etype, id) \ 311 if (FTRACE_CMP_TYPE(var, etype)) { \ 312 var = (typeof(var))(entry); \ 313 WARN_ON(id && (entry)->type != id); \ 314 break; \ 315 } 316 317 /* Will cause compile errors if type is not found. */ 318 extern void __ftrace_bad_type(void); 319 320 /* 321 * The trace_assign_type is a verifier that the entry type is 322 * the same as the type being assigned. To add new types simply 323 * add a line with the following format: 324 * 325 * IF_ASSIGN(var, ent, type, id); 326 * 327 * Where "type" is the trace type that includes the trace_entry 328 * as the "ent" item. And "id" is the trace identifier that is 329 * used in the trace_type enum. 330 * 331 * If the type can have more than one id, then use zero. 332 */ 333 #define trace_assign_type(var, ent) \ 334 do { \ 335 IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN); \ 336 IF_ASSIGN(var, ent, struct ctx_switch_entry, 0); \ 337 IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK); \ 338 IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\ 339 IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT); \ 340 IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT); \ 341 IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS); \ 342 IF_ASSIGN(var, ent, struct hwlat_entry, TRACE_HWLAT); \ 343 IF_ASSIGN(var, ent, struct raw_data_entry, TRACE_RAW_DATA);\ 344 IF_ASSIGN(var, ent, struct trace_mmiotrace_rw, \ 345 TRACE_MMIO_RW); \ 346 IF_ASSIGN(var, ent, struct trace_mmiotrace_map, \ 347 TRACE_MMIO_MAP); \ 348 IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \ 349 IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry, \ 350 TRACE_GRAPH_ENT); \ 351 IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry, \ 352 TRACE_GRAPH_RET); \ 353 __ftrace_bad_type(); \ 354 } while (0) 355 356 /* 357 * An option specific to a tracer. This is a boolean value. 358 * The bit is the bit index that sets its value on the 359 * flags value in struct tracer_flags. 360 */ 361 struct tracer_opt { 362 const char *name; /* Will appear on the trace_options file */ 363 u32 bit; /* Mask assigned in val field in tracer_flags */ 364 }; 365 366 /* 367 * The set of specific options for a tracer. Your tracer 368 * have to set the initial value of the flags val. 369 */ 370 struct tracer_flags { 371 u32 val; 372 struct tracer_opt *opts; 373 struct tracer *trace; 374 }; 375 376 /* Makes more easy to define a tracer opt */ 377 #define TRACER_OPT(s, b) .name = #s, .bit = b 378 379 380 struct trace_option_dentry { 381 struct tracer_opt *opt; 382 struct tracer_flags *flags; 383 struct trace_array *tr; 384 struct dentry *entry; 385 }; 386 387 /** 388 * struct tracer - a specific tracer and its callbacks to interact with tracefs 389 * @name: the name chosen to select it on the available_tracers file 390 * @init: called when one switches to this tracer (echo name > current_tracer) 391 * @reset: called when one switches to another tracer 392 * @start: called when tracing is unpaused (echo 1 > tracing_on) 393 * @stop: called when tracing is paused (echo 0 > tracing_on) 394 * @update_thresh: called when tracing_thresh is updated 395 * @open: called when the trace file is opened 396 * @pipe_open: called when the trace_pipe file is opened 397 * @close: called when the trace file is released 398 * @pipe_close: called when the trace_pipe file is released 399 * @read: override the default read callback on trace_pipe 400 * @splice_read: override the default splice_read callback on trace_pipe 401 * @selftest: selftest to run on boot (see trace_selftest.c) 402 * @print_headers: override the first lines that describe your columns 403 * @print_line: callback that prints a trace 404 * @set_flag: signals one of your private flags changed (trace_options file) 405 * @flags: your private flags 406 */ 407 struct tracer { 408 const char *name; 409 int (*init)(struct trace_array *tr); 410 void (*reset)(struct trace_array *tr); 411 void (*start)(struct trace_array *tr); 412 void (*stop)(struct trace_array *tr); 413 int (*update_thresh)(struct trace_array *tr); 414 void (*open)(struct trace_iterator *iter); 415 void (*pipe_open)(struct trace_iterator *iter); 416 void (*close)(struct trace_iterator *iter); 417 void (*pipe_close)(struct trace_iterator *iter); 418 ssize_t (*read)(struct trace_iterator *iter, 419 struct file *filp, char __user *ubuf, 420 size_t cnt, loff_t *ppos); 421 ssize_t (*splice_read)(struct trace_iterator *iter, 422 struct file *filp, 423 loff_t *ppos, 424 struct pipe_inode_info *pipe, 425 size_t len, 426 unsigned int flags); 427 #ifdef CONFIG_FTRACE_STARTUP_TEST 428 int (*selftest)(struct tracer *trace, 429 struct trace_array *tr); 430 #endif 431 void (*print_header)(struct seq_file *m); 432 enum print_line_t (*print_line)(struct trace_iterator *iter); 433 /* If you handled the flag setting, return 0 */ 434 int (*set_flag)(struct trace_array *tr, 435 u32 old_flags, u32 bit, int set); 436 /* Return 0 if OK with change, else return non-zero */ 437 int (*flag_changed)(struct trace_array *tr, 438 u32 mask, int set); 439 struct tracer *next; 440 struct tracer_flags *flags; 441 int enabled; 442 int ref; 443 bool print_max; 444 bool allow_instances; 445 #ifdef CONFIG_TRACER_MAX_TRACE 446 bool use_max_tr; 447 #endif 448 /* True if tracer cannot be enabled in kernel param */ 449 bool noboot; 450 }; 451 452 453 /* Only current can touch trace_recursion */ 454 455 /* 456 * For function tracing recursion: 457 * The order of these bits are important. 458 * 459 * When function tracing occurs, the following steps are made: 460 * If arch does not support a ftrace feature: 461 * call internal function (uses INTERNAL bits) which calls... 462 * If callback is registered to the "global" list, the list 463 * function is called and recursion checks the GLOBAL bits. 464 * then this function calls... 465 * The function callback, which can use the FTRACE bits to 466 * check for recursion. 467 * 468 * Now if the arch does not suppport a feature, and it calls 469 * the global list function which calls the ftrace callback 470 * all three of these steps will do a recursion protection. 471 * There's no reason to do one if the previous caller already 472 * did. The recursion that we are protecting against will 473 * go through the same steps again. 474 * 475 * To prevent the multiple recursion checks, if a recursion 476 * bit is set that is higher than the MAX bit of the current 477 * check, then we know that the check was made by the previous 478 * caller, and we can skip the current check. 479 */ 480 enum { 481 TRACE_BUFFER_BIT, 482 TRACE_BUFFER_NMI_BIT, 483 TRACE_BUFFER_IRQ_BIT, 484 TRACE_BUFFER_SIRQ_BIT, 485 486 /* Start of function recursion bits */ 487 TRACE_FTRACE_BIT, 488 TRACE_FTRACE_NMI_BIT, 489 TRACE_FTRACE_IRQ_BIT, 490 TRACE_FTRACE_SIRQ_BIT, 491 492 /* INTERNAL_BITs must be greater than FTRACE_BITs */ 493 TRACE_INTERNAL_BIT, 494 TRACE_INTERNAL_NMI_BIT, 495 TRACE_INTERNAL_IRQ_BIT, 496 TRACE_INTERNAL_SIRQ_BIT, 497 498 TRACE_BRANCH_BIT, 499 /* 500 * Abuse of the trace_recursion. 501 * As we need a way to maintain state if we are tracing the function 502 * graph in irq because we want to trace a particular function that 503 * was called in irq context but we have irq tracing off. Since this 504 * can only be modified by current, we can reuse trace_recursion. 505 */ 506 TRACE_IRQ_BIT, 507 }; 508 509 #define trace_recursion_set(bit) do { (current)->trace_recursion |= (1<<(bit)); } while (0) 510 #define trace_recursion_clear(bit) do { (current)->trace_recursion &= ~(1<<(bit)); } while (0) 511 #define trace_recursion_test(bit) ((current)->trace_recursion & (1<<(bit))) 512 513 #define TRACE_CONTEXT_BITS 4 514 515 #define TRACE_FTRACE_START TRACE_FTRACE_BIT 516 #define TRACE_FTRACE_MAX ((1 << (TRACE_FTRACE_START + TRACE_CONTEXT_BITS)) - 1) 517 518 #define TRACE_LIST_START TRACE_INTERNAL_BIT 519 #define TRACE_LIST_MAX ((1 << (TRACE_LIST_START + TRACE_CONTEXT_BITS)) - 1) 520 521 #define TRACE_CONTEXT_MASK TRACE_LIST_MAX 522 523 static __always_inline int trace_get_context_bit(void) 524 { 525 int bit; 526 527 if (in_interrupt()) { 528 if (in_nmi()) 529 bit = 0; 530 531 else if (in_irq()) 532 bit = 1; 533 else 534 bit = 2; 535 } else 536 bit = 3; 537 538 return bit; 539 } 540 541 static __always_inline int trace_test_and_set_recursion(int start, int max) 542 { 543 unsigned int val = current->trace_recursion; 544 int bit; 545 546 /* A previous recursion check was made */ 547 if ((val & TRACE_CONTEXT_MASK) > max) 548 return 0; 549 550 bit = trace_get_context_bit() + start; 551 if (unlikely(val & (1 << bit))) 552 return -1; 553 554 val |= 1 << bit; 555 current->trace_recursion = val; 556 barrier(); 557 558 return bit; 559 } 560 561 static __always_inline void trace_clear_recursion(int bit) 562 { 563 unsigned int val = current->trace_recursion; 564 565 if (!bit) 566 return; 567 568 bit = 1 << bit; 569 val &= ~bit; 570 571 barrier(); 572 current->trace_recursion = val; 573 } 574 575 static inline struct ring_buffer_iter * 576 trace_buffer_iter(struct trace_iterator *iter, int cpu) 577 { 578 if (iter->buffer_iter && iter->buffer_iter[cpu]) 579 return iter->buffer_iter[cpu]; 580 return NULL; 581 } 582 583 int tracer_init(struct tracer *t, struct trace_array *tr); 584 int tracing_is_enabled(void); 585 void tracing_reset(struct trace_buffer *buf, int cpu); 586 void tracing_reset_online_cpus(struct trace_buffer *buf); 587 void tracing_reset_current(int cpu); 588 void tracing_reset_all_online_cpus(void); 589 int tracing_open_generic(struct inode *inode, struct file *filp); 590 bool tracing_is_disabled(void); 591 int tracer_tracing_is_on(struct trace_array *tr); 592 void tracer_tracing_on(struct trace_array *tr); 593 void tracer_tracing_off(struct trace_array *tr); 594 struct dentry *trace_create_file(const char *name, 595 umode_t mode, 596 struct dentry *parent, 597 void *data, 598 const struct file_operations *fops); 599 600 struct dentry *tracing_init_dentry(void); 601 602 struct ring_buffer_event; 603 604 struct ring_buffer_event * 605 trace_buffer_lock_reserve(struct ring_buffer *buffer, 606 int type, 607 unsigned long len, 608 unsigned long flags, 609 int pc); 610 611 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr, 612 struct trace_array_cpu *data); 613 614 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, 615 int *ent_cpu, u64 *ent_ts); 616 617 void trace_buffer_unlock_commit_nostack(struct ring_buffer *buffer, 618 struct ring_buffer_event *event); 619 620 int trace_empty(struct trace_iterator *iter); 621 622 void *trace_find_next_entry_inc(struct trace_iterator *iter); 623 624 void trace_init_global_iter(struct trace_iterator *iter); 625 626 void tracing_iter_reset(struct trace_iterator *iter, int cpu); 627 628 void trace_function(struct trace_array *tr, 629 unsigned long ip, 630 unsigned long parent_ip, 631 unsigned long flags, int pc); 632 void trace_graph_function(struct trace_array *tr, 633 unsigned long ip, 634 unsigned long parent_ip, 635 unsigned long flags, int pc); 636 void trace_latency_header(struct seq_file *m); 637 void trace_default_header(struct seq_file *m); 638 void print_trace_header(struct seq_file *m, struct trace_iterator *iter); 639 int trace_empty(struct trace_iterator *iter); 640 641 void trace_graph_return(struct ftrace_graph_ret *trace); 642 int trace_graph_entry(struct ftrace_graph_ent *trace); 643 void set_graph_array(struct trace_array *tr); 644 645 void tracing_start_cmdline_record(void); 646 void tracing_stop_cmdline_record(void); 647 void tracing_start_tgid_record(void); 648 void tracing_stop_tgid_record(void); 649 650 int register_tracer(struct tracer *type); 651 int is_tracing_stopped(void); 652 653 loff_t tracing_lseek(struct file *file, loff_t offset, int whence); 654 655 extern cpumask_var_t __read_mostly tracing_buffer_mask; 656 657 #define for_each_tracing_cpu(cpu) \ 658 for_each_cpu(cpu, tracing_buffer_mask) 659 660 extern unsigned long nsecs_to_usecs(unsigned long nsecs); 661 662 extern unsigned long tracing_thresh; 663 664 /* PID filtering */ 665 666 extern int pid_max; 667 668 bool trace_find_filtered_pid(struct trace_pid_list *filtered_pids, 669 pid_t search_pid); 670 bool trace_ignore_this_task(struct trace_pid_list *filtered_pids, 671 struct task_struct *task); 672 void trace_filter_add_remove_task(struct trace_pid_list *pid_list, 673 struct task_struct *self, 674 struct task_struct *task); 675 void *trace_pid_next(struct trace_pid_list *pid_list, void *v, loff_t *pos); 676 void *trace_pid_start(struct trace_pid_list *pid_list, loff_t *pos); 677 int trace_pid_show(struct seq_file *m, void *v); 678 void trace_free_pid_list(struct trace_pid_list *pid_list); 679 int trace_pid_write(struct trace_pid_list *filtered_pids, 680 struct trace_pid_list **new_pid_list, 681 const char __user *ubuf, size_t cnt); 682 683 #ifdef CONFIG_TRACER_MAX_TRACE 684 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu); 685 void update_max_tr_single(struct trace_array *tr, 686 struct task_struct *tsk, int cpu); 687 #endif /* CONFIG_TRACER_MAX_TRACE */ 688 689 #ifdef CONFIG_STACKTRACE 690 void ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, 691 int pc); 692 693 void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, 694 int pc); 695 #else 696 static inline void ftrace_trace_userstack(struct ring_buffer *buffer, 697 unsigned long flags, int pc) 698 { 699 } 700 701 static inline void __trace_stack(struct trace_array *tr, unsigned long flags, 702 int skip, int pc) 703 { 704 } 705 #endif /* CONFIG_STACKTRACE */ 706 707 extern u64 ftrace_now(int cpu); 708 709 extern void trace_find_cmdline(int pid, char comm[]); 710 extern int trace_find_tgid(int pid); 711 extern void trace_event_follow_fork(struct trace_array *tr, bool enable); 712 713 #ifdef CONFIG_DYNAMIC_FTRACE 714 extern unsigned long ftrace_update_tot_cnt; 715 void ftrace_init_trace_array(struct trace_array *tr); 716 #else 717 static inline void ftrace_init_trace_array(struct trace_array *tr) { } 718 #endif 719 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func 720 extern int DYN_FTRACE_TEST_NAME(void); 721 #define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2 722 extern int DYN_FTRACE_TEST_NAME2(void); 723 724 extern bool ring_buffer_expanded; 725 extern bool tracing_selftest_disabled; 726 727 #ifdef CONFIG_FTRACE_STARTUP_TEST 728 extern int trace_selftest_startup_function(struct tracer *trace, 729 struct trace_array *tr); 730 extern int trace_selftest_startup_function_graph(struct tracer *trace, 731 struct trace_array *tr); 732 extern int trace_selftest_startup_irqsoff(struct tracer *trace, 733 struct trace_array *tr); 734 extern int trace_selftest_startup_preemptoff(struct tracer *trace, 735 struct trace_array *tr); 736 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace, 737 struct trace_array *tr); 738 extern int trace_selftest_startup_wakeup(struct tracer *trace, 739 struct trace_array *tr); 740 extern int trace_selftest_startup_nop(struct tracer *trace, 741 struct trace_array *tr); 742 extern int trace_selftest_startup_sched_switch(struct tracer *trace, 743 struct trace_array *tr); 744 extern int trace_selftest_startup_branch(struct tracer *trace, 745 struct trace_array *tr); 746 /* 747 * Tracer data references selftest functions that only occur 748 * on boot up. These can be __init functions. Thus, when selftests 749 * are enabled, then the tracers need to reference __init functions. 750 */ 751 #define __tracer_data __refdata 752 #else 753 /* Tracers are seldom changed. Optimize when selftests are disabled. */ 754 #define __tracer_data __read_mostly 755 #endif /* CONFIG_FTRACE_STARTUP_TEST */ 756 757 extern void *head_page(struct trace_array_cpu *data); 758 extern unsigned long long ns2usecs(u64 nsec); 759 extern int 760 trace_vbprintk(unsigned long ip, const char *fmt, va_list args); 761 extern int 762 trace_vprintk(unsigned long ip, const char *fmt, va_list args); 763 extern int 764 trace_array_vprintk(struct trace_array *tr, 765 unsigned long ip, const char *fmt, va_list args); 766 int trace_array_printk(struct trace_array *tr, 767 unsigned long ip, const char *fmt, ...); 768 int trace_array_printk_buf(struct ring_buffer *buffer, 769 unsigned long ip, const char *fmt, ...); 770 void trace_printk_seq(struct trace_seq *s); 771 enum print_line_t print_trace_line(struct trace_iterator *iter); 772 773 extern char trace_find_mark(unsigned long long duration); 774 775 struct ftrace_hash; 776 777 struct ftrace_mod_load { 778 struct list_head list; 779 char *func; 780 char *module; 781 int enable; 782 }; 783 784 enum { 785 FTRACE_HASH_FL_MOD = (1 << 0), 786 }; 787 788 struct ftrace_hash { 789 unsigned long size_bits; 790 struct hlist_head *buckets; 791 unsigned long count; 792 unsigned long flags; 793 struct rcu_head rcu; 794 }; 795 796 struct ftrace_func_entry * 797 ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip); 798 799 static __always_inline bool ftrace_hash_empty(struct ftrace_hash *hash) 800 { 801 return !hash || !(hash->count || (hash->flags & FTRACE_HASH_FL_MOD)); 802 } 803 804 /* Standard output formatting function used for function return traces */ 805 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 806 807 /* Flag options */ 808 #define TRACE_GRAPH_PRINT_OVERRUN 0x1 809 #define TRACE_GRAPH_PRINT_CPU 0x2 810 #define TRACE_GRAPH_PRINT_OVERHEAD 0x4 811 #define TRACE_GRAPH_PRINT_PROC 0x8 812 #define TRACE_GRAPH_PRINT_DURATION 0x10 813 #define TRACE_GRAPH_PRINT_ABS_TIME 0x20 814 #define TRACE_GRAPH_PRINT_IRQS 0x40 815 #define TRACE_GRAPH_PRINT_TAIL 0x80 816 #define TRACE_GRAPH_SLEEP_TIME 0x100 817 #define TRACE_GRAPH_GRAPH_TIME 0x200 818 #define TRACE_GRAPH_PRINT_FILL_SHIFT 28 819 #define TRACE_GRAPH_PRINT_FILL_MASK (0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT) 820 821 extern void ftrace_graph_sleep_time_control(bool enable); 822 extern void ftrace_graph_graph_time_control(bool enable); 823 824 extern enum print_line_t 825 print_graph_function_flags(struct trace_iterator *iter, u32 flags); 826 extern void print_graph_headers_flags(struct seq_file *s, u32 flags); 827 extern void 828 trace_print_graph_duration(unsigned long long duration, struct trace_seq *s); 829 extern void graph_trace_open(struct trace_iterator *iter); 830 extern void graph_trace_close(struct trace_iterator *iter); 831 extern int __trace_graph_entry(struct trace_array *tr, 832 struct ftrace_graph_ent *trace, 833 unsigned long flags, int pc); 834 extern void __trace_graph_return(struct trace_array *tr, 835 struct ftrace_graph_ret *trace, 836 unsigned long flags, int pc); 837 838 #ifdef CONFIG_DYNAMIC_FTRACE 839 extern struct ftrace_hash *ftrace_graph_hash; 840 extern struct ftrace_hash *ftrace_graph_notrace_hash; 841 842 static inline int ftrace_graph_addr(unsigned long addr) 843 { 844 int ret = 0; 845 846 preempt_disable_notrace(); 847 848 if (ftrace_hash_empty(ftrace_graph_hash)) { 849 ret = 1; 850 goto out; 851 } 852 853 if (ftrace_lookup_ip(ftrace_graph_hash, addr)) { 854 /* 855 * If no irqs are to be traced, but a set_graph_function 856 * is set, and called by an interrupt handler, we still 857 * want to trace it. 858 */ 859 if (in_irq()) 860 trace_recursion_set(TRACE_IRQ_BIT); 861 else 862 trace_recursion_clear(TRACE_IRQ_BIT); 863 ret = 1; 864 } 865 866 out: 867 preempt_enable_notrace(); 868 return ret; 869 } 870 871 static inline int ftrace_graph_notrace_addr(unsigned long addr) 872 { 873 int ret = 0; 874 875 preempt_disable_notrace(); 876 877 if (ftrace_lookup_ip(ftrace_graph_notrace_hash, addr)) 878 ret = 1; 879 880 preempt_enable_notrace(); 881 return ret; 882 } 883 #else 884 static inline int ftrace_graph_addr(unsigned long addr) 885 { 886 return 1; 887 } 888 889 static inline int ftrace_graph_notrace_addr(unsigned long addr) 890 { 891 return 0; 892 } 893 #endif /* CONFIG_DYNAMIC_FTRACE */ 894 895 extern unsigned int fgraph_max_depth; 896 897 static inline bool ftrace_graph_ignore_func(struct ftrace_graph_ent *trace) 898 { 899 /* trace it when it is-nested-in or is a function enabled. */ 900 return !(trace->depth || ftrace_graph_addr(trace->func)) || 901 (trace->depth < 0) || 902 (fgraph_max_depth && trace->depth >= fgraph_max_depth); 903 } 904 905 #else /* CONFIG_FUNCTION_GRAPH_TRACER */ 906 static inline enum print_line_t 907 print_graph_function_flags(struct trace_iterator *iter, u32 flags) 908 { 909 return TRACE_TYPE_UNHANDLED; 910 } 911 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ 912 913 extern struct list_head ftrace_pids; 914 915 #ifdef CONFIG_FUNCTION_TRACER 916 struct ftrace_func_command { 917 struct list_head list; 918 char *name; 919 int (*func)(struct trace_array *tr, 920 struct ftrace_hash *hash, 921 char *func, char *cmd, 922 char *params, int enable); 923 }; 924 extern bool ftrace_filter_param __initdata; 925 static inline int ftrace_trace_task(struct trace_array *tr) 926 { 927 return !this_cpu_read(tr->trace_buffer.data->ftrace_ignore_pid); 928 } 929 extern int ftrace_is_dead(void); 930 int ftrace_create_function_files(struct trace_array *tr, 931 struct dentry *parent); 932 void ftrace_destroy_function_files(struct trace_array *tr); 933 void ftrace_init_global_array_ops(struct trace_array *tr); 934 void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func); 935 void ftrace_reset_array_ops(struct trace_array *tr); 936 int using_ftrace_ops_list_func(void); 937 void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer); 938 void ftrace_init_tracefs_toplevel(struct trace_array *tr, 939 struct dentry *d_tracer); 940 void ftrace_clear_pids(struct trace_array *tr); 941 int init_function_trace(void); 942 void ftrace_pid_follow_fork(struct trace_array *tr, bool enable); 943 #else 944 static inline int ftrace_trace_task(struct trace_array *tr) 945 { 946 return 1; 947 } 948 static inline int ftrace_is_dead(void) { return 0; } 949 static inline int 950 ftrace_create_function_files(struct trace_array *tr, 951 struct dentry *parent) 952 { 953 return 0; 954 } 955 static inline void ftrace_destroy_function_files(struct trace_array *tr) { } 956 static inline __init void 957 ftrace_init_global_array_ops(struct trace_array *tr) { } 958 static inline void ftrace_reset_array_ops(struct trace_array *tr) { } 959 static inline void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d) { } 960 static inline void ftrace_init_tracefs_toplevel(struct trace_array *tr, struct dentry *d) { } 961 static inline void ftrace_clear_pids(struct trace_array *tr) { } 962 static inline int init_function_trace(void) { return 0; } 963 static inline void ftrace_pid_follow_fork(struct trace_array *tr, bool enable) { } 964 /* ftace_func_t type is not defined, use macro instead of static inline */ 965 #define ftrace_init_array_ops(tr, func) do { } while (0) 966 #endif /* CONFIG_FUNCTION_TRACER */ 967 968 #if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE) 969 970 struct ftrace_probe_ops { 971 void (*func)(unsigned long ip, 972 unsigned long parent_ip, 973 struct trace_array *tr, 974 struct ftrace_probe_ops *ops, 975 void *data); 976 int (*init)(struct ftrace_probe_ops *ops, 977 struct trace_array *tr, 978 unsigned long ip, void *init_data, 979 void **data); 980 void (*free)(struct ftrace_probe_ops *ops, 981 struct trace_array *tr, 982 unsigned long ip, void *data); 983 int (*print)(struct seq_file *m, 984 unsigned long ip, 985 struct ftrace_probe_ops *ops, 986 void *data); 987 }; 988 989 struct ftrace_func_mapper; 990 typedef int (*ftrace_mapper_func)(void *data); 991 992 struct ftrace_func_mapper *allocate_ftrace_func_mapper(void); 993 void **ftrace_func_mapper_find_ip(struct ftrace_func_mapper *mapper, 994 unsigned long ip); 995 int ftrace_func_mapper_add_ip(struct ftrace_func_mapper *mapper, 996 unsigned long ip, void *data); 997 void *ftrace_func_mapper_remove_ip(struct ftrace_func_mapper *mapper, 998 unsigned long ip); 999 void free_ftrace_func_mapper(struct ftrace_func_mapper *mapper, 1000 ftrace_mapper_func free_func); 1001 1002 extern int 1003 register_ftrace_function_probe(char *glob, struct trace_array *tr, 1004 struct ftrace_probe_ops *ops, void *data); 1005 extern int 1006 unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr, 1007 struct ftrace_probe_ops *ops); 1008 extern void clear_ftrace_function_probes(struct trace_array *tr); 1009 1010 int register_ftrace_command(struct ftrace_func_command *cmd); 1011 int unregister_ftrace_command(struct ftrace_func_command *cmd); 1012 1013 void ftrace_create_filter_files(struct ftrace_ops *ops, 1014 struct dentry *parent); 1015 void ftrace_destroy_filter_files(struct ftrace_ops *ops); 1016 #else 1017 struct ftrace_func_command; 1018 1019 static inline __init int register_ftrace_command(struct ftrace_func_command *cmd) 1020 { 1021 return -EINVAL; 1022 } 1023 static inline __init int unregister_ftrace_command(char *cmd_name) 1024 { 1025 return -EINVAL; 1026 } 1027 static inline void clear_ftrace_function_probes(struct trace_array *tr) 1028 { 1029 } 1030 1031 /* 1032 * The ops parameter passed in is usually undefined. 1033 * This must be a macro. 1034 */ 1035 #define ftrace_create_filter_files(ops, parent) do { } while (0) 1036 #define ftrace_destroy_filter_files(ops) do { } while (0) 1037 #endif /* CONFIG_FUNCTION_TRACER && CONFIG_DYNAMIC_FTRACE */ 1038 1039 bool ftrace_event_is_function(struct trace_event_call *call); 1040 1041 /* 1042 * struct trace_parser - servers for reading the user input separated by spaces 1043 * @cont: set if the input is not complete - no final space char was found 1044 * @buffer: holds the parsed user input 1045 * @idx: user input length 1046 * @size: buffer size 1047 */ 1048 struct trace_parser { 1049 bool cont; 1050 char *buffer; 1051 unsigned idx; 1052 unsigned size; 1053 }; 1054 1055 static inline bool trace_parser_loaded(struct trace_parser *parser) 1056 { 1057 return (parser->idx != 0); 1058 } 1059 1060 static inline bool trace_parser_cont(struct trace_parser *parser) 1061 { 1062 return parser->cont; 1063 } 1064 1065 static inline void trace_parser_clear(struct trace_parser *parser) 1066 { 1067 parser->cont = false; 1068 parser->idx = 0; 1069 } 1070 1071 extern int trace_parser_get_init(struct trace_parser *parser, int size); 1072 extern void trace_parser_put(struct trace_parser *parser); 1073 extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf, 1074 size_t cnt, loff_t *ppos); 1075 1076 /* 1077 * Only create function graph options if function graph is configured. 1078 */ 1079 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 1080 # define FGRAPH_FLAGS \ 1081 C(DISPLAY_GRAPH, "display-graph"), 1082 #else 1083 # define FGRAPH_FLAGS 1084 #endif 1085 1086 #ifdef CONFIG_BRANCH_TRACER 1087 # define BRANCH_FLAGS \ 1088 C(BRANCH, "branch"), 1089 #else 1090 # define BRANCH_FLAGS 1091 #endif 1092 1093 #ifdef CONFIG_FUNCTION_TRACER 1094 # define FUNCTION_FLAGS \ 1095 C(FUNCTION, "function-trace"), \ 1096 C(FUNC_FORK, "function-fork"), 1097 # define FUNCTION_DEFAULT_FLAGS TRACE_ITER_FUNCTION 1098 #else 1099 # define FUNCTION_FLAGS 1100 # define FUNCTION_DEFAULT_FLAGS 0UL 1101 # define TRACE_ITER_FUNC_FORK 0UL 1102 #endif 1103 1104 #ifdef CONFIG_STACKTRACE 1105 # define STACK_FLAGS \ 1106 C(STACKTRACE, "stacktrace"), 1107 #else 1108 # define STACK_FLAGS 1109 #endif 1110 1111 /* 1112 * trace_iterator_flags is an enumeration that defines bit 1113 * positions into trace_flags that controls the output. 1114 * 1115 * NOTE: These bits must match the trace_options array in 1116 * trace.c (this macro guarantees it). 1117 */ 1118 #define TRACE_FLAGS \ 1119 C(PRINT_PARENT, "print-parent"), \ 1120 C(SYM_OFFSET, "sym-offset"), \ 1121 C(SYM_ADDR, "sym-addr"), \ 1122 C(VERBOSE, "verbose"), \ 1123 C(RAW, "raw"), \ 1124 C(HEX, "hex"), \ 1125 C(BIN, "bin"), \ 1126 C(BLOCK, "block"), \ 1127 C(PRINTK, "trace_printk"), \ 1128 C(ANNOTATE, "annotate"), \ 1129 C(USERSTACKTRACE, "userstacktrace"), \ 1130 C(SYM_USEROBJ, "sym-userobj"), \ 1131 C(PRINTK_MSGONLY, "printk-msg-only"), \ 1132 C(CONTEXT_INFO, "context-info"), /* Print pid/cpu/time */ \ 1133 C(LATENCY_FMT, "latency-format"), \ 1134 C(RECORD_CMD, "record-cmd"), \ 1135 C(RECORD_TGID, "record-tgid"), \ 1136 C(OVERWRITE, "overwrite"), \ 1137 C(STOP_ON_FREE, "disable_on_free"), \ 1138 C(IRQ_INFO, "irq-info"), \ 1139 C(MARKERS, "markers"), \ 1140 C(EVENT_FORK, "event-fork"), \ 1141 FUNCTION_FLAGS \ 1142 FGRAPH_FLAGS \ 1143 STACK_FLAGS \ 1144 BRANCH_FLAGS 1145 1146 /* 1147 * By defining C, we can make TRACE_FLAGS a list of bit names 1148 * that will define the bits for the flag masks. 1149 */ 1150 #undef C 1151 #define C(a, b) TRACE_ITER_##a##_BIT 1152 1153 enum trace_iterator_bits { 1154 TRACE_FLAGS 1155 /* Make sure we don't go more than we have bits for */ 1156 TRACE_ITER_LAST_BIT 1157 }; 1158 1159 /* 1160 * By redefining C, we can make TRACE_FLAGS a list of masks that 1161 * use the bits as defined above. 1162 */ 1163 #undef C 1164 #define C(a, b) TRACE_ITER_##a = (1 << TRACE_ITER_##a##_BIT) 1165 1166 enum trace_iterator_flags { TRACE_FLAGS }; 1167 1168 /* 1169 * TRACE_ITER_SYM_MASK masks the options in trace_flags that 1170 * control the output of kernel symbols. 1171 */ 1172 #define TRACE_ITER_SYM_MASK \ 1173 (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR) 1174 1175 extern struct tracer nop_trace; 1176 1177 #ifdef CONFIG_BRANCH_TRACER 1178 extern int enable_branch_tracing(struct trace_array *tr); 1179 extern void disable_branch_tracing(void); 1180 static inline int trace_branch_enable(struct trace_array *tr) 1181 { 1182 if (tr->trace_flags & TRACE_ITER_BRANCH) 1183 return enable_branch_tracing(tr); 1184 return 0; 1185 } 1186 static inline void trace_branch_disable(void) 1187 { 1188 /* due to races, always disable */ 1189 disable_branch_tracing(); 1190 } 1191 #else 1192 static inline int trace_branch_enable(struct trace_array *tr) 1193 { 1194 return 0; 1195 } 1196 static inline void trace_branch_disable(void) 1197 { 1198 } 1199 #endif /* CONFIG_BRANCH_TRACER */ 1200 1201 /* set ring buffers to default size if not already done so */ 1202 int tracing_update_buffers(void); 1203 1204 struct ftrace_event_field { 1205 struct list_head link; 1206 const char *name; 1207 const char *type; 1208 int filter_type; 1209 int offset; 1210 int size; 1211 int is_signed; 1212 }; 1213 1214 struct event_filter { 1215 int n_preds; /* Number assigned */ 1216 int a_preds; /* allocated */ 1217 struct filter_pred __rcu *preds; 1218 struct filter_pred __rcu *root; 1219 char *filter_string; 1220 }; 1221 1222 struct event_subsystem { 1223 struct list_head list; 1224 const char *name; 1225 struct event_filter *filter; 1226 int ref_count; 1227 }; 1228 1229 struct trace_subsystem_dir { 1230 struct list_head list; 1231 struct event_subsystem *subsystem; 1232 struct trace_array *tr; 1233 struct dentry *entry; 1234 int ref_count; 1235 int nr_events; 1236 }; 1237 1238 extern int call_filter_check_discard(struct trace_event_call *call, void *rec, 1239 struct ring_buffer *buffer, 1240 struct ring_buffer_event *event); 1241 1242 void trace_buffer_unlock_commit_regs(struct trace_array *tr, 1243 struct ring_buffer *buffer, 1244 struct ring_buffer_event *event, 1245 unsigned long flags, int pc, 1246 struct pt_regs *regs); 1247 1248 static inline void trace_buffer_unlock_commit(struct trace_array *tr, 1249 struct ring_buffer *buffer, 1250 struct ring_buffer_event *event, 1251 unsigned long flags, int pc) 1252 { 1253 trace_buffer_unlock_commit_regs(tr, buffer, event, flags, pc, NULL); 1254 } 1255 1256 DECLARE_PER_CPU(struct ring_buffer_event *, trace_buffered_event); 1257 DECLARE_PER_CPU(int, trace_buffered_event_cnt); 1258 void trace_buffered_event_disable(void); 1259 void trace_buffered_event_enable(void); 1260 1261 static inline void 1262 __trace_event_discard_commit(struct ring_buffer *buffer, 1263 struct ring_buffer_event *event) 1264 { 1265 if (this_cpu_read(trace_buffered_event) == event) { 1266 /* Simply release the temp buffer */ 1267 this_cpu_dec(trace_buffered_event_cnt); 1268 return; 1269 } 1270 ring_buffer_discard_commit(buffer, event); 1271 } 1272 1273 /* 1274 * Helper function for event_trigger_unlock_commit{_regs}(). 1275 * If there are event triggers attached to this event that requires 1276 * filtering against its fields, then they wil be called as the 1277 * entry already holds the field information of the current event. 1278 * 1279 * It also checks if the event should be discarded or not. 1280 * It is to be discarded if the event is soft disabled and the 1281 * event was only recorded to process triggers, or if the event 1282 * filter is active and this event did not match the filters. 1283 * 1284 * Returns true if the event is discarded, false otherwise. 1285 */ 1286 static inline bool 1287 __event_trigger_test_discard(struct trace_event_file *file, 1288 struct ring_buffer *buffer, 1289 struct ring_buffer_event *event, 1290 void *entry, 1291 enum event_trigger_type *tt) 1292 { 1293 unsigned long eflags = file->flags; 1294 1295 if (eflags & EVENT_FILE_FL_TRIGGER_COND) 1296 *tt = event_triggers_call(file, entry); 1297 1298 if (test_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &file->flags) || 1299 (unlikely(file->flags & EVENT_FILE_FL_FILTERED) && 1300 !filter_match_preds(file->filter, entry))) { 1301 __trace_event_discard_commit(buffer, event); 1302 return true; 1303 } 1304 1305 return false; 1306 } 1307 1308 /** 1309 * event_trigger_unlock_commit - handle triggers and finish event commit 1310 * @file: The file pointer assoctiated to the event 1311 * @buffer: The ring buffer that the event is being written to 1312 * @event: The event meta data in the ring buffer 1313 * @entry: The event itself 1314 * @irq_flags: The state of the interrupts at the start of the event 1315 * @pc: The state of the preempt count at the start of the event. 1316 * 1317 * This is a helper function to handle triggers that require data 1318 * from the event itself. It also tests the event against filters and 1319 * if the event is soft disabled and should be discarded. 1320 */ 1321 static inline void 1322 event_trigger_unlock_commit(struct trace_event_file *file, 1323 struct ring_buffer *buffer, 1324 struct ring_buffer_event *event, 1325 void *entry, unsigned long irq_flags, int pc) 1326 { 1327 enum event_trigger_type tt = ETT_NONE; 1328 1329 if (!__event_trigger_test_discard(file, buffer, event, entry, &tt)) 1330 trace_buffer_unlock_commit(file->tr, buffer, event, irq_flags, pc); 1331 1332 if (tt) 1333 event_triggers_post_call(file, tt, entry); 1334 } 1335 1336 /** 1337 * event_trigger_unlock_commit_regs - handle triggers and finish event commit 1338 * @file: The file pointer assoctiated to the event 1339 * @buffer: The ring buffer that the event is being written to 1340 * @event: The event meta data in the ring buffer 1341 * @entry: The event itself 1342 * @irq_flags: The state of the interrupts at the start of the event 1343 * @pc: The state of the preempt count at the start of the event. 1344 * 1345 * This is a helper function to handle triggers that require data 1346 * from the event itself. It also tests the event against filters and 1347 * if the event is soft disabled and should be discarded. 1348 * 1349 * Same as event_trigger_unlock_commit() but calls 1350 * trace_buffer_unlock_commit_regs() instead of trace_buffer_unlock_commit(). 1351 */ 1352 static inline void 1353 event_trigger_unlock_commit_regs(struct trace_event_file *file, 1354 struct ring_buffer *buffer, 1355 struct ring_buffer_event *event, 1356 void *entry, unsigned long irq_flags, int pc, 1357 struct pt_regs *regs) 1358 { 1359 enum event_trigger_type tt = ETT_NONE; 1360 1361 if (!__event_trigger_test_discard(file, buffer, event, entry, &tt)) 1362 trace_buffer_unlock_commit_regs(file->tr, buffer, event, 1363 irq_flags, pc, regs); 1364 1365 if (tt) 1366 event_triggers_post_call(file, tt, entry); 1367 } 1368 1369 #define FILTER_PRED_INVALID ((unsigned short)-1) 1370 #define FILTER_PRED_IS_RIGHT (1 << 15) 1371 #define FILTER_PRED_FOLD (1 << 15) 1372 1373 /* 1374 * The max preds is the size of unsigned short with 1375 * two flags at the MSBs. One bit is used for both the IS_RIGHT 1376 * and FOLD flags. The other is reserved. 1377 * 1378 * 2^14 preds is way more than enough. 1379 */ 1380 #define MAX_FILTER_PRED 16384 1381 1382 struct filter_pred; 1383 struct regex; 1384 1385 typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event); 1386 1387 typedef int (*regex_match_func)(char *str, struct regex *r, int len); 1388 1389 enum regex_type { 1390 MATCH_FULL = 0, 1391 MATCH_FRONT_ONLY, 1392 MATCH_MIDDLE_ONLY, 1393 MATCH_END_ONLY, 1394 MATCH_GLOB, 1395 }; 1396 1397 struct regex { 1398 char pattern[MAX_FILTER_STR_VAL]; 1399 int len; 1400 int field_len; 1401 regex_match_func match; 1402 }; 1403 1404 struct filter_pred { 1405 filter_pred_fn_t fn; 1406 u64 val; 1407 struct regex regex; 1408 unsigned short *ops; 1409 struct ftrace_event_field *field; 1410 int offset; 1411 int not; 1412 int op; 1413 unsigned short index; 1414 unsigned short parent; 1415 unsigned short left; 1416 unsigned short right; 1417 }; 1418 1419 static inline bool is_string_field(struct ftrace_event_field *field) 1420 { 1421 return field->filter_type == FILTER_DYN_STRING || 1422 field->filter_type == FILTER_STATIC_STRING || 1423 field->filter_type == FILTER_PTR_STRING || 1424 field->filter_type == FILTER_COMM; 1425 } 1426 1427 static inline bool is_function_field(struct ftrace_event_field *field) 1428 { 1429 return field->filter_type == FILTER_TRACE_FN; 1430 } 1431 1432 extern enum regex_type 1433 filter_parse_regex(char *buff, int len, char **search, int *not); 1434 extern void print_event_filter(struct trace_event_file *file, 1435 struct trace_seq *s); 1436 extern int apply_event_filter(struct trace_event_file *file, 1437 char *filter_string); 1438 extern int apply_subsystem_event_filter(struct trace_subsystem_dir *dir, 1439 char *filter_string); 1440 extern void print_subsystem_event_filter(struct event_subsystem *system, 1441 struct trace_seq *s); 1442 extern int filter_assign_type(const char *type); 1443 extern int create_event_filter(struct trace_event_call *call, 1444 char *filter_str, bool set_str, 1445 struct event_filter **filterp); 1446 extern void free_event_filter(struct event_filter *filter); 1447 1448 struct ftrace_event_field * 1449 trace_find_event_field(struct trace_event_call *call, char *name); 1450 1451 extern void trace_event_enable_cmd_record(bool enable); 1452 extern void trace_event_enable_tgid_record(bool enable); 1453 1454 extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr); 1455 extern int event_trace_del_tracer(struct trace_array *tr); 1456 1457 extern struct trace_event_file *find_event_file(struct trace_array *tr, 1458 const char *system, 1459 const char *event); 1460 1461 static inline void *event_file_data(struct file *filp) 1462 { 1463 return ACCESS_ONCE(file_inode(filp)->i_private); 1464 } 1465 1466 extern struct mutex event_mutex; 1467 extern struct list_head ftrace_events; 1468 1469 extern const struct file_operations event_trigger_fops; 1470 extern const struct file_operations event_hist_fops; 1471 1472 #ifdef CONFIG_HIST_TRIGGERS 1473 extern int register_trigger_hist_cmd(void); 1474 extern int register_trigger_hist_enable_disable_cmds(void); 1475 #else 1476 static inline int register_trigger_hist_cmd(void) { return 0; } 1477 static inline int register_trigger_hist_enable_disable_cmds(void) { return 0; } 1478 #endif 1479 1480 extern int register_trigger_cmds(void); 1481 extern void clear_event_triggers(struct trace_array *tr); 1482 1483 struct event_trigger_data { 1484 unsigned long count; 1485 int ref; 1486 struct event_trigger_ops *ops; 1487 struct event_command *cmd_ops; 1488 struct event_filter __rcu *filter; 1489 char *filter_str; 1490 void *private_data; 1491 bool paused; 1492 bool paused_tmp; 1493 struct list_head list; 1494 char *name; 1495 struct list_head named_list; 1496 struct event_trigger_data *named_data; 1497 }; 1498 1499 /* Avoid typos */ 1500 #define ENABLE_EVENT_STR "enable_event" 1501 #define DISABLE_EVENT_STR "disable_event" 1502 #define ENABLE_HIST_STR "enable_hist" 1503 #define DISABLE_HIST_STR "disable_hist" 1504 1505 struct enable_trigger_data { 1506 struct trace_event_file *file; 1507 bool enable; 1508 bool hist; 1509 }; 1510 1511 extern int event_enable_trigger_print(struct seq_file *m, 1512 struct event_trigger_ops *ops, 1513 struct event_trigger_data *data); 1514 extern void event_enable_trigger_free(struct event_trigger_ops *ops, 1515 struct event_trigger_data *data); 1516 extern int event_enable_trigger_func(struct event_command *cmd_ops, 1517 struct trace_event_file *file, 1518 char *glob, char *cmd, char *param); 1519 extern int event_enable_register_trigger(char *glob, 1520 struct event_trigger_ops *ops, 1521 struct event_trigger_data *data, 1522 struct trace_event_file *file); 1523 extern void event_enable_unregister_trigger(char *glob, 1524 struct event_trigger_ops *ops, 1525 struct event_trigger_data *test, 1526 struct trace_event_file *file); 1527 extern void trigger_data_free(struct event_trigger_data *data); 1528 extern int event_trigger_init(struct event_trigger_ops *ops, 1529 struct event_trigger_data *data); 1530 extern int trace_event_trigger_enable_disable(struct trace_event_file *file, 1531 int trigger_enable); 1532 extern void update_cond_flag(struct trace_event_file *file); 1533 extern void unregister_trigger(char *glob, struct event_trigger_ops *ops, 1534 struct event_trigger_data *test, 1535 struct trace_event_file *file); 1536 extern int set_trigger_filter(char *filter_str, 1537 struct event_trigger_data *trigger_data, 1538 struct trace_event_file *file); 1539 extern struct event_trigger_data *find_named_trigger(const char *name); 1540 extern bool is_named_trigger(struct event_trigger_data *test); 1541 extern int save_named_trigger(const char *name, 1542 struct event_trigger_data *data); 1543 extern void del_named_trigger(struct event_trigger_data *data); 1544 extern void pause_named_trigger(struct event_trigger_data *data); 1545 extern void unpause_named_trigger(struct event_trigger_data *data); 1546 extern void set_named_trigger_data(struct event_trigger_data *data, 1547 struct event_trigger_data *named_data); 1548 extern int register_event_command(struct event_command *cmd); 1549 extern int unregister_event_command(struct event_command *cmd); 1550 extern int register_trigger_hist_enable_disable_cmds(void); 1551 1552 /** 1553 * struct event_trigger_ops - callbacks for trace event triggers 1554 * 1555 * The methods in this structure provide per-event trigger hooks for 1556 * various trigger operations. 1557 * 1558 * All the methods below, except for @init() and @free(), must be 1559 * implemented. 1560 * 1561 * @func: The trigger 'probe' function called when the triggering 1562 * event occurs. The data passed into this callback is the data 1563 * that was supplied to the event_command @reg() function that 1564 * registered the trigger (see struct event_command) along with 1565 * the trace record, rec. 1566 * 1567 * @init: An optional initialization function called for the trigger 1568 * when the trigger is registered (via the event_command reg() 1569 * function). This can be used to perform per-trigger 1570 * initialization such as incrementing a per-trigger reference 1571 * count, for instance. This is usually implemented by the 1572 * generic utility function @event_trigger_init() (see 1573 * trace_event_triggers.c). 1574 * 1575 * @free: An optional de-initialization function called for the 1576 * trigger when the trigger is unregistered (via the 1577 * event_command @reg() function). This can be used to perform 1578 * per-trigger de-initialization such as decrementing a 1579 * per-trigger reference count and freeing corresponding trigger 1580 * data, for instance. This is usually implemented by the 1581 * generic utility function @event_trigger_free() (see 1582 * trace_event_triggers.c). 1583 * 1584 * @print: The callback function invoked to have the trigger print 1585 * itself. This is usually implemented by a wrapper function 1586 * that calls the generic utility function @event_trigger_print() 1587 * (see trace_event_triggers.c). 1588 */ 1589 struct event_trigger_ops { 1590 void (*func)(struct event_trigger_data *data, 1591 void *rec); 1592 int (*init)(struct event_trigger_ops *ops, 1593 struct event_trigger_data *data); 1594 void (*free)(struct event_trigger_ops *ops, 1595 struct event_trigger_data *data); 1596 int (*print)(struct seq_file *m, 1597 struct event_trigger_ops *ops, 1598 struct event_trigger_data *data); 1599 }; 1600 1601 /** 1602 * struct event_command - callbacks and data members for event commands 1603 * 1604 * Event commands are invoked by users by writing the command name 1605 * into the 'trigger' file associated with a trace event. The 1606 * parameters associated with a specific invocation of an event 1607 * command are used to create an event trigger instance, which is 1608 * added to the list of trigger instances associated with that trace 1609 * event. When the event is hit, the set of triggers associated with 1610 * that event is invoked. 1611 * 1612 * The data members in this structure provide per-event command data 1613 * for various event commands. 1614 * 1615 * All the data members below, except for @post_trigger, must be set 1616 * for each event command. 1617 * 1618 * @name: The unique name that identifies the event command. This is 1619 * the name used when setting triggers via trigger files. 1620 * 1621 * @trigger_type: A unique id that identifies the event command 1622 * 'type'. This value has two purposes, the first to ensure that 1623 * only one trigger of the same type can be set at a given time 1624 * for a particular event e.g. it doesn't make sense to have both 1625 * a traceon and traceoff trigger attached to a single event at 1626 * the same time, so traceon and traceoff have the same type 1627 * though they have different names. The @trigger_type value is 1628 * also used as a bit value for deferring the actual trigger 1629 * action until after the current event is finished. Some 1630 * commands need to do this if they themselves log to the trace 1631 * buffer (see the @post_trigger() member below). @trigger_type 1632 * values are defined by adding new values to the trigger_type 1633 * enum in include/linux/trace_events.h. 1634 * 1635 * @flags: See the enum event_command_flags below. 1636 * 1637 * All the methods below, except for @set_filter() and @unreg_all(), 1638 * must be implemented. 1639 * 1640 * @func: The callback function responsible for parsing and 1641 * registering the trigger written to the 'trigger' file by the 1642 * user. It allocates the trigger instance and registers it with 1643 * the appropriate trace event. It makes use of the other 1644 * event_command callback functions to orchestrate this, and is 1645 * usually implemented by the generic utility function 1646 * @event_trigger_callback() (see trace_event_triggers.c). 1647 * 1648 * @reg: Adds the trigger to the list of triggers associated with the 1649 * event, and enables the event trigger itself, after 1650 * initializing it (via the event_trigger_ops @init() function). 1651 * This is also where commands can use the @trigger_type value to 1652 * make the decision as to whether or not multiple instances of 1653 * the trigger should be allowed. This is usually implemented by 1654 * the generic utility function @register_trigger() (see 1655 * trace_event_triggers.c). 1656 * 1657 * @unreg: Removes the trigger from the list of triggers associated 1658 * with the event, and disables the event trigger itself, after 1659 * initializing it (via the event_trigger_ops @free() function). 1660 * This is usually implemented by the generic utility function 1661 * @unregister_trigger() (see trace_event_triggers.c). 1662 * 1663 * @unreg_all: An optional function called to remove all the triggers 1664 * from the list of triggers associated with the event. Called 1665 * when a trigger file is opened in truncate mode. 1666 * 1667 * @set_filter: An optional function called to parse and set a filter 1668 * for the trigger. If no @set_filter() method is set for the 1669 * event command, filters set by the user for the command will be 1670 * ignored. This is usually implemented by the generic utility 1671 * function @set_trigger_filter() (see trace_event_triggers.c). 1672 * 1673 * @get_trigger_ops: The callback function invoked to retrieve the 1674 * event_trigger_ops implementation associated with the command. 1675 */ 1676 struct event_command { 1677 struct list_head list; 1678 char *name; 1679 enum event_trigger_type trigger_type; 1680 int flags; 1681 int (*func)(struct event_command *cmd_ops, 1682 struct trace_event_file *file, 1683 char *glob, char *cmd, char *params); 1684 int (*reg)(char *glob, 1685 struct event_trigger_ops *ops, 1686 struct event_trigger_data *data, 1687 struct trace_event_file *file); 1688 void (*unreg)(char *glob, 1689 struct event_trigger_ops *ops, 1690 struct event_trigger_data *data, 1691 struct trace_event_file *file); 1692 void (*unreg_all)(struct trace_event_file *file); 1693 int (*set_filter)(char *filter_str, 1694 struct event_trigger_data *data, 1695 struct trace_event_file *file); 1696 struct event_trigger_ops *(*get_trigger_ops)(char *cmd, char *param); 1697 }; 1698 1699 /** 1700 * enum event_command_flags - flags for struct event_command 1701 * 1702 * @POST_TRIGGER: A flag that says whether or not this command needs 1703 * to have its action delayed until after the current event has 1704 * been closed. Some triggers need to avoid being invoked while 1705 * an event is currently in the process of being logged, since 1706 * the trigger may itself log data into the trace buffer. Thus 1707 * we make sure the current event is committed before invoking 1708 * those triggers. To do that, the trigger invocation is split 1709 * in two - the first part checks the filter using the current 1710 * trace record; if a command has the @post_trigger flag set, it 1711 * sets a bit for itself in the return value, otherwise it 1712 * directly invokes the trigger. Once all commands have been 1713 * either invoked or set their return flag, the current record is 1714 * either committed or discarded. At that point, if any commands 1715 * have deferred their triggers, those commands are finally 1716 * invoked following the close of the current event. In other 1717 * words, if the event_trigger_ops @func() probe implementation 1718 * itself logs to the trace buffer, this flag should be set, 1719 * otherwise it can be left unspecified. 1720 * 1721 * @NEEDS_REC: A flag that says whether or not this command needs 1722 * access to the trace record in order to perform its function, 1723 * regardless of whether or not it has a filter associated with 1724 * it (filters make a trigger require access to the trace record 1725 * but are not always present). 1726 */ 1727 enum event_command_flags { 1728 EVENT_CMD_FL_POST_TRIGGER = 1, 1729 EVENT_CMD_FL_NEEDS_REC = 2, 1730 }; 1731 1732 static inline bool event_command_post_trigger(struct event_command *cmd_ops) 1733 { 1734 return cmd_ops->flags & EVENT_CMD_FL_POST_TRIGGER; 1735 } 1736 1737 static inline bool event_command_needs_rec(struct event_command *cmd_ops) 1738 { 1739 return cmd_ops->flags & EVENT_CMD_FL_NEEDS_REC; 1740 } 1741 1742 extern int trace_event_enable_disable(struct trace_event_file *file, 1743 int enable, int soft_disable); 1744 extern int tracing_alloc_snapshot(void); 1745 1746 extern const char *__start___trace_bprintk_fmt[]; 1747 extern const char *__stop___trace_bprintk_fmt[]; 1748 1749 extern const char *__start___tracepoint_str[]; 1750 extern const char *__stop___tracepoint_str[]; 1751 1752 void trace_printk_control(bool enabled); 1753 void trace_printk_init_buffers(void); 1754 void trace_printk_start_comm(void); 1755 int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set); 1756 int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled); 1757 1758 /* 1759 * Normal trace_printk() and friends allocates special buffers 1760 * to do the manipulation, as well as saves the print formats 1761 * into sections to display. But the trace infrastructure wants 1762 * to use these without the added overhead at the price of being 1763 * a bit slower (used mainly for warnings, where we don't care 1764 * about performance). The internal_trace_puts() is for such 1765 * a purpose. 1766 */ 1767 #define internal_trace_puts(str) __trace_puts(_THIS_IP_, str, strlen(str)) 1768 1769 #undef FTRACE_ENTRY 1770 #define FTRACE_ENTRY(call, struct_name, id, tstruct, print, filter) \ 1771 extern struct trace_event_call \ 1772 __aligned(4) event_##call; 1773 #undef FTRACE_ENTRY_DUP 1774 #define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print, filter) \ 1775 FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print), \ 1776 filter) 1777 #undef FTRACE_ENTRY_PACKED 1778 #define FTRACE_ENTRY_PACKED(call, struct_name, id, tstruct, print, filter) \ 1779 FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print), \ 1780 filter) 1781 1782 #include "trace_entries.h" 1783 1784 #if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER) 1785 int perf_ftrace_event_register(struct trace_event_call *call, 1786 enum trace_reg type, void *data); 1787 #else 1788 #define perf_ftrace_event_register NULL 1789 #endif 1790 1791 #ifdef CONFIG_FTRACE_SYSCALLS 1792 void init_ftrace_syscalls(void); 1793 const char *get_syscall_name(int syscall); 1794 #else 1795 static inline void init_ftrace_syscalls(void) { } 1796 static inline const char *get_syscall_name(int syscall) 1797 { 1798 return NULL; 1799 } 1800 #endif 1801 1802 #ifdef CONFIG_EVENT_TRACING 1803 void trace_event_init(void); 1804 void trace_event_eval_update(struct trace_eval_map **map, int len); 1805 #else 1806 static inline void __init trace_event_init(void) { } 1807 static inline void trace_event_eval_update(struct trace_eval_map **map, int len) { } 1808 #endif 1809 1810 extern struct trace_iterator *tracepoint_print_iter; 1811 1812 #endif /* _LINUX_KERNEL_TRACE_H */ 1813