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 struct trace_event_file *trace_marker_file; 263 cpumask_var_t tracing_cpumask; /* only trace on set CPUs */ 264 int ref; 265 #ifdef CONFIG_FUNCTION_TRACER 266 struct ftrace_ops *ops; 267 struct trace_pid_list __rcu *function_pids; 268 #ifdef CONFIG_DYNAMIC_FTRACE 269 /* All of these are protected by the ftrace_lock */ 270 struct list_head func_probes; 271 struct list_head mod_trace; 272 struct list_head mod_notrace; 273 #endif 274 /* function tracing enabled */ 275 int function_enabled; 276 #endif 277 int time_stamp_abs_ref; 278 struct list_head hist_vars; 279 }; 280 281 enum { 282 TRACE_ARRAY_FL_GLOBAL = (1 << 0) 283 }; 284 285 extern struct list_head ftrace_trace_arrays; 286 287 extern struct mutex trace_types_lock; 288 289 extern int trace_array_get(struct trace_array *tr); 290 extern void trace_array_put(struct trace_array *tr); 291 292 extern int tracing_set_time_stamp_abs(struct trace_array *tr, bool abs); 293 extern int tracing_set_clock(struct trace_array *tr, const char *clockstr); 294 295 extern bool trace_clock_in_ns(struct trace_array *tr); 296 297 /* 298 * The global tracer (top) should be the first trace array added, 299 * but we check the flag anyway. 300 */ 301 static inline struct trace_array *top_trace_array(void) 302 { 303 struct trace_array *tr; 304 305 if (list_empty(&ftrace_trace_arrays)) 306 return NULL; 307 308 tr = list_entry(ftrace_trace_arrays.prev, 309 typeof(*tr), list); 310 WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL)); 311 return tr; 312 } 313 314 #define FTRACE_CMP_TYPE(var, type) \ 315 __builtin_types_compatible_p(typeof(var), type *) 316 317 #undef IF_ASSIGN 318 #define IF_ASSIGN(var, entry, etype, id) \ 319 if (FTRACE_CMP_TYPE(var, etype)) { \ 320 var = (typeof(var))(entry); \ 321 WARN_ON(id && (entry)->type != id); \ 322 break; \ 323 } 324 325 /* Will cause compile errors if type is not found. */ 326 extern void __ftrace_bad_type(void); 327 328 /* 329 * The trace_assign_type is a verifier that the entry type is 330 * the same as the type being assigned. To add new types simply 331 * add a line with the following format: 332 * 333 * IF_ASSIGN(var, ent, type, id); 334 * 335 * Where "type" is the trace type that includes the trace_entry 336 * as the "ent" item. And "id" is the trace identifier that is 337 * used in the trace_type enum. 338 * 339 * If the type can have more than one id, then use zero. 340 */ 341 #define trace_assign_type(var, ent) \ 342 do { \ 343 IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN); \ 344 IF_ASSIGN(var, ent, struct ctx_switch_entry, 0); \ 345 IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK); \ 346 IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\ 347 IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT); \ 348 IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT); \ 349 IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS); \ 350 IF_ASSIGN(var, ent, struct hwlat_entry, TRACE_HWLAT); \ 351 IF_ASSIGN(var, ent, struct raw_data_entry, TRACE_RAW_DATA);\ 352 IF_ASSIGN(var, ent, struct trace_mmiotrace_rw, \ 353 TRACE_MMIO_RW); \ 354 IF_ASSIGN(var, ent, struct trace_mmiotrace_map, \ 355 TRACE_MMIO_MAP); \ 356 IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \ 357 IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry, \ 358 TRACE_GRAPH_ENT); \ 359 IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry, \ 360 TRACE_GRAPH_RET); \ 361 __ftrace_bad_type(); \ 362 } while (0) 363 364 /* 365 * An option specific to a tracer. This is a boolean value. 366 * The bit is the bit index that sets its value on the 367 * flags value in struct tracer_flags. 368 */ 369 struct tracer_opt { 370 const char *name; /* Will appear on the trace_options file */ 371 u32 bit; /* Mask assigned in val field in tracer_flags */ 372 }; 373 374 /* 375 * The set of specific options for a tracer. Your tracer 376 * have to set the initial value of the flags val. 377 */ 378 struct tracer_flags { 379 u32 val; 380 struct tracer_opt *opts; 381 struct tracer *trace; 382 }; 383 384 /* Makes more easy to define a tracer opt */ 385 #define TRACER_OPT(s, b) .name = #s, .bit = b 386 387 388 struct trace_option_dentry { 389 struct tracer_opt *opt; 390 struct tracer_flags *flags; 391 struct trace_array *tr; 392 struct dentry *entry; 393 }; 394 395 /** 396 * struct tracer - a specific tracer and its callbacks to interact with tracefs 397 * @name: the name chosen to select it on the available_tracers file 398 * @init: called when one switches to this tracer (echo name > current_tracer) 399 * @reset: called when one switches to another tracer 400 * @start: called when tracing is unpaused (echo 1 > tracing_on) 401 * @stop: called when tracing is paused (echo 0 > tracing_on) 402 * @update_thresh: called when tracing_thresh is updated 403 * @open: called when the trace file is opened 404 * @pipe_open: called when the trace_pipe file is opened 405 * @close: called when the trace file is released 406 * @pipe_close: called when the trace_pipe file is released 407 * @read: override the default read callback on trace_pipe 408 * @splice_read: override the default splice_read callback on trace_pipe 409 * @selftest: selftest to run on boot (see trace_selftest.c) 410 * @print_headers: override the first lines that describe your columns 411 * @print_line: callback that prints a trace 412 * @set_flag: signals one of your private flags changed (trace_options file) 413 * @flags: your private flags 414 */ 415 struct tracer { 416 const char *name; 417 int (*init)(struct trace_array *tr); 418 void (*reset)(struct trace_array *tr); 419 void (*start)(struct trace_array *tr); 420 void (*stop)(struct trace_array *tr); 421 int (*update_thresh)(struct trace_array *tr); 422 void (*open)(struct trace_iterator *iter); 423 void (*pipe_open)(struct trace_iterator *iter); 424 void (*close)(struct trace_iterator *iter); 425 void (*pipe_close)(struct trace_iterator *iter); 426 ssize_t (*read)(struct trace_iterator *iter, 427 struct file *filp, char __user *ubuf, 428 size_t cnt, loff_t *ppos); 429 ssize_t (*splice_read)(struct trace_iterator *iter, 430 struct file *filp, 431 loff_t *ppos, 432 struct pipe_inode_info *pipe, 433 size_t len, 434 unsigned int flags); 435 #ifdef CONFIG_FTRACE_STARTUP_TEST 436 int (*selftest)(struct tracer *trace, 437 struct trace_array *tr); 438 #endif 439 void (*print_header)(struct seq_file *m); 440 enum print_line_t (*print_line)(struct trace_iterator *iter); 441 /* If you handled the flag setting, return 0 */ 442 int (*set_flag)(struct trace_array *tr, 443 u32 old_flags, u32 bit, int set); 444 /* Return 0 if OK with change, else return non-zero */ 445 int (*flag_changed)(struct trace_array *tr, 446 u32 mask, int set); 447 struct tracer *next; 448 struct tracer_flags *flags; 449 int enabled; 450 int ref; 451 bool print_max; 452 bool allow_instances; 453 #ifdef CONFIG_TRACER_MAX_TRACE 454 bool use_max_tr; 455 #endif 456 /* True if tracer cannot be enabled in kernel param */ 457 bool noboot; 458 }; 459 460 461 /* Only current can touch trace_recursion */ 462 463 /* 464 * For function tracing recursion: 465 * The order of these bits are important. 466 * 467 * When function tracing occurs, the following steps are made: 468 * If arch does not support a ftrace feature: 469 * call internal function (uses INTERNAL bits) which calls... 470 * If callback is registered to the "global" list, the list 471 * function is called and recursion checks the GLOBAL bits. 472 * then this function calls... 473 * The function callback, which can use the FTRACE bits to 474 * check for recursion. 475 * 476 * Now if the arch does not suppport a feature, and it calls 477 * the global list function which calls the ftrace callback 478 * all three of these steps will do a recursion protection. 479 * There's no reason to do one if the previous caller already 480 * did. The recursion that we are protecting against will 481 * go through the same steps again. 482 * 483 * To prevent the multiple recursion checks, if a recursion 484 * bit is set that is higher than the MAX bit of the current 485 * check, then we know that the check was made by the previous 486 * caller, and we can skip the current check. 487 */ 488 enum { 489 TRACE_BUFFER_BIT, 490 TRACE_BUFFER_NMI_BIT, 491 TRACE_BUFFER_IRQ_BIT, 492 TRACE_BUFFER_SIRQ_BIT, 493 494 /* Start of function recursion bits */ 495 TRACE_FTRACE_BIT, 496 TRACE_FTRACE_NMI_BIT, 497 TRACE_FTRACE_IRQ_BIT, 498 TRACE_FTRACE_SIRQ_BIT, 499 500 /* INTERNAL_BITs must be greater than FTRACE_BITs */ 501 TRACE_INTERNAL_BIT, 502 TRACE_INTERNAL_NMI_BIT, 503 TRACE_INTERNAL_IRQ_BIT, 504 TRACE_INTERNAL_SIRQ_BIT, 505 506 TRACE_BRANCH_BIT, 507 /* 508 * Abuse of the trace_recursion. 509 * As we need a way to maintain state if we are tracing the function 510 * graph in irq because we want to trace a particular function that 511 * was called in irq context but we have irq tracing off. Since this 512 * can only be modified by current, we can reuse trace_recursion. 513 */ 514 TRACE_IRQ_BIT, 515 }; 516 517 #define trace_recursion_set(bit) do { (current)->trace_recursion |= (1<<(bit)); } while (0) 518 #define trace_recursion_clear(bit) do { (current)->trace_recursion &= ~(1<<(bit)); } while (0) 519 #define trace_recursion_test(bit) ((current)->trace_recursion & (1<<(bit))) 520 521 #define TRACE_CONTEXT_BITS 4 522 523 #define TRACE_FTRACE_START TRACE_FTRACE_BIT 524 #define TRACE_FTRACE_MAX ((1 << (TRACE_FTRACE_START + TRACE_CONTEXT_BITS)) - 1) 525 526 #define TRACE_LIST_START TRACE_INTERNAL_BIT 527 #define TRACE_LIST_MAX ((1 << (TRACE_LIST_START + TRACE_CONTEXT_BITS)) - 1) 528 529 #define TRACE_CONTEXT_MASK TRACE_LIST_MAX 530 531 static __always_inline int trace_get_context_bit(void) 532 { 533 int bit; 534 535 if (in_interrupt()) { 536 if (in_nmi()) 537 bit = 0; 538 539 else if (in_irq()) 540 bit = 1; 541 else 542 bit = 2; 543 } else 544 bit = 3; 545 546 return bit; 547 } 548 549 static __always_inline int trace_test_and_set_recursion(int start, int max) 550 { 551 unsigned int val = current->trace_recursion; 552 int bit; 553 554 /* A previous recursion check was made */ 555 if ((val & TRACE_CONTEXT_MASK) > max) 556 return 0; 557 558 bit = trace_get_context_bit() + start; 559 if (unlikely(val & (1 << bit))) 560 return -1; 561 562 val |= 1 << bit; 563 current->trace_recursion = val; 564 barrier(); 565 566 return bit; 567 } 568 569 static __always_inline void trace_clear_recursion(int bit) 570 { 571 unsigned int val = current->trace_recursion; 572 573 if (!bit) 574 return; 575 576 bit = 1 << bit; 577 val &= ~bit; 578 579 barrier(); 580 current->trace_recursion = val; 581 } 582 583 static inline struct ring_buffer_iter * 584 trace_buffer_iter(struct trace_iterator *iter, int cpu) 585 { 586 return iter->buffer_iter ? iter->buffer_iter[cpu] : NULL; 587 } 588 589 int tracer_init(struct tracer *t, struct trace_array *tr); 590 int tracing_is_enabled(void); 591 void tracing_reset(struct trace_buffer *buf, int cpu); 592 void tracing_reset_online_cpus(struct trace_buffer *buf); 593 void tracing_reset_current(int cpu); 594 void tracing_reset_all_online_cpus(void); 595 int tracing_open_generic(struct inode *inode, struct file *filp); 596 bool tracing_is_disabled(void); 597 int tracer_tracing_is_on(struct trace_array *tr); 598 void tracer_tracing_on(struct trace_array *tr); 599 void tracer_tracing_off(struct trace_array *tr); 600 struct dentry *trace_create_file(const char *name, 601 umode_t mode, 602 struct dentry *parent, 603 void *data, 604 const struct file_operations *fops); 605 606 struct dentry *tracing_init_dentry(void); 607 608 struct ring_buffer_event; 609 610 struct ring_buffer_event * 611 trace_buffer_lock_reserve(struct ring_buffer *buffer, 612 int type, 613 unsigned long len, 614 unsigned long flags, 615 int pc); 616 617 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr, 618 struct trace_array_cpu *data); 619 620 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, 621 int *ent_cpu, u64 *ent_ts); 622 623 void trace_buffer_unlock_commit_nostack(struct ring_buffer *buffer, 624 struct ring_buffer_event *event); 625 626 int trace_empty(struct trace_iterator *iter); 627 628 void *trace_find_next_entry_inc(struct trace_iterator *iter); 629 630 void trace_init_global_iter(struct trace_iterator *iter); 631 632 void tracing_iter_reset(struct trace_iterator *iter, int cpu); 633 634 void trace_function(struct trace_array *tr, 635 unsigned long ip, 636 unsigned long parent_ip, 637 unsigned long flags, int pc); 638 void trace_graph_function(struct trace_array *tr, 639 unsigned long ip, 640 unsigned long parent_ip, 641 unsigned long flags, int pc); 642 void trace_latency_header(struct seq_file *m); 643 void trace_default_header(struct seq_file *m); 644 void print_trace_header(struct seq_file *m, struct trace_iterator *iter); 645 int trace_empty(struct trace_iterator *iter); 646 647 void trace_graph_return(struct ftrace_graph_ret *trace); 648 int trace_graph_entry(struct ftrace_graph_ent *trace); 649 void set_graph_array(struct trace_array *tr); 650 651 void tracing_start_cmdline_record(void); 652 void tracing_stop_cmdline_record(void); 653 void tracing_start_tgid_record(void); 654 void tracing_stop_tgid_record(void); 655 656 int register_tracer(struct tracer *type); 657 int is_tracing_stopped(void); 658 659 loff_t tracing_lseek(struct file *file, loff_t offset, int whence); 660 661 extern cpumask_var_t __read_mostly tracing_buffer_mask; 662 663 #define for_each_tracing_cpu(cpu) \ 664 for_each_cpu(cpu, tracing_buffer_mask) 665 666 extern unsigned long nsecs_to_usecs(unsigned long nsecs); 667 668 extern unsigned long tracing_thresh; 669 670 /* PID filtering */ 671 672 extern int pid_max; 673 674 bool trace_find_filtered_pid(struct trace_pid_list *filtered_pids, 675 pid_t search_pid); 676 bool trace_ignore_this_task(struct trace_pid_list *filtered_pids, 677 struct task_struct *task); 678 void trace_filter_add_remove_task(struct trace_pid_list *pid_list, 679 struct task_struct *self, 680 struct task_struct *task); 681 void *trace_pid_next(struct trace_pid_list *pid_list, void *v, loff_t *pos); 682 void *trace_pid_start(struct trace_pid_list *pid_list, loff_t *pos); 683 int trace_pid_show(struct seq_file *m, void *v); 684 void trace_free_pid_list(struct trace_pid_list *pid_list); 685 int trace_pid_write(struct trace_pid_list *filtered_pids, 686 struct trace_pid_list **new_pid_list, 687 const char __user *ubuf, size_t cnt); 688 689 #ifdef CONFIG_TRACER_MAX_TRACE 690 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu); 691 void update_max_tr_single(struct trace_array *tr, 692 struct task_struct *tsk, int cpu); 693 #endif /* CONFIG_TRACER_MAX_TRACE */ 694 695 #ifdef CONFIG_STACKTRACE 696 void ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, 697 int pc); 698 699 void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, 700 int pc); 701 #else 702 static inline void ftrace_trace_userstack(struct ring_buffer *buffer, 703 unsigned long flags, int pc) 704 { 705 } 706 707 static inline void __trace_stack(struct trace_array *tr, unsigned long flags, 708 int skip, int pc) 709 { 710 } 711 #endif /* CONFIG_STACKTRACE */ 712 713 extern u64 ftrace_now(int cpu); 714 715 extern void trace_find_cmdline(int pid, char comm[]); 716 extern int trace_find_tgid(int pid); 717 extern void trace_event_follow_fork(struct trace_array *tr, bool enable); 718 719 #ifdef CONFIG_DYNAMIC_FTRACE 720 extern unsigned long ftrace_update_tot_cnt; 721 void ftrace_init_trace_array(struct trace_array *tr); 722 #else 723 static inline void ftrace_init_trace_array(struct trace_array *tr) { } 724 #endif 725 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func 726 extern int DYN_FTRACE_TEST_NAME(void); 727 #define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2 728 extern int DYN_FTRACE_TEST_NAME2(void); 729 730 extern bool ring_buffer_expanded; 731 extern bool tracing_selftest_disabled; 732 733 #ifdef CONFIG_FTRACE_STARTUP_TEST 734 extern int trace_selftest_startup_function(struct tracer *trace, 735 struct trace_array *tr); 736 extern int trace_selftest_startup_function_graph(struct tracer *trace, 737 struct trace_array *tr); 738 extern int trace_selftest_startup_irqsoff(struct tracer *trace, 739 struct trace_array *tr); 740 extern int trace_selftest_startup_preemptoff(struct tracer *trace, 741 struct trace_array *tr); 742 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace, 743 struct trace_array *tr); 744 extern int trace_selftest_startup_wakeup(struct tracer *trace, 745 struct trace_array *tr); 746 extern int trace_selftest_startup_nop(struct tracer *trace, 747 struct trace_array *tr); 748 extern int trace_selftest_startup_branch(struct tracer *trace, 749 struct trace_array *tr); 750 /* 751 * Tracer data references selftest functions that only occur 752 * on boot up. These can be __init functions. Thus, when selftests 753 * are enabled, then the tracers need to reference __init functions. 754 */ 755 #define __tracer_data __refdata 756 #else 757 /* Tracers are seldom changed. Optimize when selftests are disabled. */ 758 #define __tracer_data __read_mostly 759 #endif /* CONFIG_FTRACE_STARTUP_TEST */ 760 761 extern void *head_page(struct trace_array_cpu *data); 762 extern unsigned long long ns2usecs(u64 nsec); 763 extern int 764 trace_vbprintk(unsigned long ip, const char *fmt, va_list args); 765 extern int 766 trace_vprintk(unsigned long ip, const char *fmt, va_list args); 767 extern int 768 trace_array_vprintk(struct trace_array *tr, 769 unsigned long ip, const char *fmt, va_list args); 770 int trace_array_printk(struct trace_array *tr, 771 unsigned long ip, const char *fmt, ...); 772 int trace_array_printk_buf(struct ring_buffer *buffer, 773 unsigned long ip, const char *fmt, ...); 774 void trace_printk_seq(struct trace_seq *s); 775 enum print_line_t print_trace_line(struct trace_iterator *iter); 776 777 extern char trace_find_mark(unsigned long long duration); 778 779 struct ftrace_hash; 780 781 struct ftrace_mod_load { 782 struct list_head list; 783 char *func; 784 char *module; 785 int enable; 786 }; 787 788 enum { 789 FTRACE_HASH_FL_MOD = (1 << 0), 790 }; 791 792 struct ftrace_hash { 793 unsigned long size_bits; 794 struct hlist_head *buckets; 795 unsigned long count; 796 unsigned long flags; 797 struct rcu_head rcu; 798 }; 799 800 struct ftrace_func_entry * 801 ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip); 802 803 static __always_inline bool ftrace_hash_empty(struct ftrace_hash *hash) 804 { 805 return !hash || !(hash->count || (hash->flags & FTRACE_HASH_FL_MOD)); 806 } 807 808 /* Standard output formatting function used for function return traces */ 809 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 810 811 /* Flag options */ 812 #define TRACE_GRAPH_PRINT_OVERRUN 0x1 813 #define TRACE_GRAPH_PRINT_CPU 0x2 814 #define TRACE_GRAPH_PRINT_OVERHEAD 0x4 815 #define TRACE_GRAPH_PRINT_PROC 0x8 816 #define TRACE_GRAPH_PRINT_DURATION 0x10 817 #define TRACE_GRAPH_PRINT_ABS_TIME 0x20 818 #define TRACE_GRAPH_PRINT_IRQS 0x40 819 #define TRACE_GRAPH_PRINT_TAIL 0x80 820 #define TRACE_GRAPH_SLEEP_TIME 0x100 821 #define TRACE_GRAPH_GRAPH_TIME 0x200 822 #define TRACE_GRAPH_PRINT_FILL_SHIFT 28 823 #define TRACE_GRAPH_PRINT_FILL_MASK (0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT) 824 825 extern void ftrace_graph_sleep_time_control(bool enable); 826 extern void ftrace_graph_graph_time_control(bool enable); 827 828 extern enum print_line_t 829 print_graph_function_flags(struct trace_iterator *iter, u32 flags); 830 extern void print_graph_headers_flags(struct seq_file *s, u32 flags); 831 extern void 832 trace_print_graph_duration(unsigned long long duration, struct trace_seq *s); 833 extern void graph_trace_open(struct trace_iterator *iter); 834 extern void graph_trace_close(struct trace_iterator *iter); 835 extern int __trace_graph_entry(struct trace_array *tr, 836 struct ftrace_graph_ent *trace, 837 unsigned long flags, int pc); 838 extern void __trace_graph_return(struct trace_array *tr, 839 struct ftrace_graph_ret *trace, 840 unsigned long flags, int pc); 841 842 #ifdef CONFIG_DYNAMIC_FTRACE 843 extern struct ftrace_hash *ftrace_graph_hash; 844 extern struct ftrace_hash *ftrace_graph_notrace_hash; 845 846 static inline int ftrace_graph_addr(unsigned long addr) 847 { 848 int ret = 0; 849 850 preempt_disable_notrace(); 851 852 if (ftrace_hash_empty(ftrace_graph_hash)) { 853 ret = 1; 854 goto out; 855 } 856 857 if (ftrace_lookup_ip(ftrace_graph_hash, addr)) { 858 /* 859 * If no irqs are to be traced, but a set_graph_function 860 * is set, and called by an interrupt handler, we still 861 * want to trace it. 862 */ 863 if (in_irq()) 864 trace_recursion_set(TRACE_IRQ_BIT); 865 else 866 trace_recursion_clear(TRACE_IRQ_BIT); 867 ret = 1; 868 } 869 870 out: 871 preempt_enable_notrace(); 872 return ret; 873 } 874 875 static inline int ftrace_graph_notrace_addr(unsigned long addr) 876 { 877 int ret = 0; 878 879 preempt_disable_notrace(); 880 881 if (ftrace_lookup_ip(ftrace_graph_notrace_hash, addr)) 882 ret = 1; 883 884 preempt_enable_notrace(); 885 return ret; 886 } 887 #else 888 static inline int ftrace_graph_addr(unsigned long addr) 889 { 890 return 1; 891 } 892 893 static inline int ftrace_graph_notrace_addr(unsigned long addr) 894 { 895 return 0; 896 } 897 #endif /* CONFIG_DYNAMIC_FTRACE */ 898 899 extern unsigned int fgraph_max_depth; 900 901 static inline bool ftrace_graph_ignore_func(struct ftrace_graph_ent *trace) 902 { 903 /* trace it when it is-nested-in or is a function enabled. */ 904 return !(trace->depth || ftrace_graph_addr(trace->func)) || 905 (trace->depth < 0) || 906 (fgraph_max_depth && trace->depth >= fgraph_max_depth); 907 } 908 909 #else /* CONFIG_FUNCTION_GRAPH_TRACER */ 910 static inline enum print_line_t 911 print_graph_function_flags(struct trace_iterator *iter, u32 flags) 912 { 913 return TRACE_TYPE_UNHANDLED; 914 } 915 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ 916 917 extern struct list_head ftrace_pids; 918 919 #ifdef CONFIG_FUNCTION_TRACER 920 struct ftrace_func_command { 921 struct list_head list; 922 char *name; 923 int (*func)(struct trace_array *tr, 924 struct ftrace_hash *hash, 925 char *func, char *cmd, 926 char *params, int enable); 927 }; 928 extern bool ftrace_filter_param __initdata; 929 static inline int ftrace_trace_task(struct trace_array *tr) 930 { 931 return !this_cpu_read(tr->trace_buffer.data->ftrace_ignore_pid); 932 } 933 extern int ftrace_is_dead(void); 934 int ftrace_create_function_files(struct trace_array *tr, 935 struct dentry *parent); 936 void ftrace_destroy_function_files(struct trace_array *tr); 937 void ftrace_init_global_array_ops(struct trace_array *tr); 938 void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func); 939 void ftrace_reset_array_ops(struct trace_array *tr); 940 int using_ftrace_ops_list_func(void); 941 void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer); 942 void ftrace_init_tracefs_toplevel(struct trace_array *tr, 943 struct dentry *d_tracer); 944 void ftrace_clear_pids(struct trace_array *tr); 945 int init_function_trace(void); 946 void ftrace_pid_follow_fork(struct trace_array *tr, bool enable); 947 #else 948 static inline int ftrace_trace_task(struct trace_array *tr) 949 { 950 return 1; 951 } 952 static inline int ftrace_is_dead(void) { return 0; } 953 static inline int 954 ftrace_create_function_files(struct trace_array *tr, 955 struct dentry *parent) 956 { 957 return 0; 958 } 959 static inline void ftrace_destroy_function_files(struct trace_array *tr) { } 960 static inline __init void 961 ftrace_init_global_array_ops(struct trace_array *tr) { } 962 static inline void ftrace_reset_array_ops(struct trace_array *tr) { } 963 static inline void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d) { } 964 static inline void ftrace_init_tracefs_toplevel(struct trace_array *tr, struct dentry *d) { } 965 static inline void ftrace_clear_pids(struct trace_array *tr) { } 966 static inline int init_function_trace(void) { return 0; } 967 static inline void ftrace_pid_follow_fork(struct trace_array *tr, bool enable) { } 968 /* ftace_func_t type is not defined, use macro instead of static inline */ 969 #define ftrace_init_array_ops(tr, func) do { } while (0) 970 #endif /* CONFIG_FUNCTION_TRACER */ 971 972 #if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE) 973 974 struct ftrace_probe_ops { 975 void (*func)(unsigned long ip, 976 unsigned long parent_ip, 977 struct trace_array *tr, 978 struct ftrace_probe_ops *ops, 979 void *data); 980 int (*init)(struct ftrace_probe_ops *ops, 981 struct trace_array *tr, 982 unsigned long ip, void *init_data, 983 void **data); 984 void (*free)(struct ftrace_probe_ops *ops, 985 struct trace_array *tr, 986 unsigned long ip, void *data); 987 int (*print)(struct seq_file *m, 988 unsigned long ip, 989 struct ftrace_probe_ops *ops, 990 void *data); 991 }; 992 993 struct ftrace_func_mapper; 994 typedef int (*ftrace_mapper_func)(void *data); 995 996 struct ftrace_func_mapper *allocate_ftrace_func_mapper(void); 997 void **ftrace_func_mapper_find_ip(struct ftrace_func_mapper *mapper, 998 unsigned long ip); 999 int ftrace_func_mapper_add_ip(struct ftrace_func_mapper *mapper, 1000 unsigned long ip, void *data); 1001 void *ftrace_func_mapper_remove_ip(struct ftrace_func_mapper *mapper, 1002 unsigned long ip); 1003 void free_ftrace_func_mapper(struct ftrace_func_mapper *mapper, 1004 ftrace_mapper_func free_func); 1005 1006 extern int 1007 register_ftrace_function_probe(char *glob, struct trace_array *tr, 1008 struct ftrace_probe_ops *ops, void *data); 1009 extern int 1010 unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr, 1011 struct ftrace_probe_ops *ops); 1012 extern void clear_ftrace_function_probes(struct trace_array *tr); 1013 1014 int register_ftrace_command(struct ftrace_func_command *cmd); 1015 int unregister_ftrace_command(struct ftrace_func_command *cmd); 1016 1017 void ftrace_create_filter_files(struct ftrace_ops *ops, 1018 struct dentry *parent); 1019 void ftrace_destroy_filter_files(struct ftrace_ops *ops); 1020 #else 1021 struct ftrace_func_command; 1022 1023 static inline __init int register_ftrace_command(struct ftrace_func_command *cmd) 1024 { 1025 return -EINVAL; 1026 } 1027 static inline __init int unregister_ftrace_command(char *cmd_name) 1028 { 1029 return -EINVAL; 1030 } 1031 static inline void clear_ftrace_function_probes(struct trace_array *tr) 1032 { 1033 } 1034 1035 /* 1036 * The ops parameter passed in is usually undefined. 1037 * This must be a macro. 1038 */ 1039 #define ftrace_create_filter_files(ops, parent) do { } while (0) 1040 #define ftrace_destroy_filter_files(ops) do { } while (0) 1041 #endif /* CONFIG_FUNCTION_TRACER && CONFIG_DYNAMIC_FTRACE */ 1042 1043 bool ftrace_event_is_function(struct trace_event_call *call); 1044 1045 /* 1046 * struct trace_parser - servers for reading the user input separated by spaces 1047 * @cont: set if the input is not complete - no final space char was found 1048 * @buffer: holds the parsed user input 1049 * @idx: user input length 1050 * @size: buffer size 1051 */ 1052 struct trace_parser { 1053 bool cont; 1054 char *buffer; 1055 unsigned idx; 1056 unsigned size; 1057 }; 1058 1059 static inline bool trace_parser_loaded(struct trace_parser *parser) 1060 { 1061 return (parser->idx != 0); 1062 } 1063 1064 static inline bool trace_parser_cont(struct trace_parser *parser) 1065 { 1066 return parser->cont; 1067 } 1068 1069 static inline void trace_parser_clear(struct trace_parser *parser) 1070 { 1071 parser->cont = false; 1072 parser->idx = 0; 1073 } 1074 1075 extern int trace_parser_get_init(struct trace_parser *parser, int size); 1076 extern void trace_parser_put(struct trace_parser *parser); 1077 extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf, 1078 size_t cnt, loff_t *ppos); 1079 1080 /* 1081 * Only create function graph options if function graph is configured. 1082 */ 1083 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 1084 # define FGRAPH_FLAGS \ 1085 C(DISPLAY_GRAPH, "display-graph"), 1086 #else 1087 # define FGRAPH_FLAGS 1088 #endif 1089 1090 #ifdef CONFIG_BRANCH_TRACER 1091 # define BRANCH_FLAGS \ 1092 C(BRANCH, "branch"), 1093 #else 1094 # define BRANCH_FLAGS 1095 #endif 1096 1097 #ifdef CONFIG_FUNCTION_TRACER 1098 # define FUNCTION_FLAGS \ 1099 C(FUNCTION, "function-trace"), \ 1100 C(FUNC_FORK, "function-fork"), 1101 # define FUNCTION_DEFAULT_FLAGS TRACE_ITER_FUNCTION 1102 #else 1103 # define FUNCTION_FLAGS 1104 # define FUNCTION_DEFAULT_FLAGS 0UL 1105 # define TRACE_ITER_FUNC_FORK 0UL 1106 #endif 1107 1108 #ifdef CONFIG_STACKTRACE 1109 # define STACK_FLAGS \ 1110 C(STACKTRACE, "stacktrace"), 1111 #else 1112 # define STACK_FLAGS 1113 #endif 1114 1115 /* 1116 * trace_iterator_flags is an enumeration that defines bit 1117 * positions into trace_flags that controls the output. 1118 * 1119 * NOTE: These bits must match the trace_options array in 1120 * trace.c (this macro guarantees it). 1121 */ 1122 #define TRACE_FLAGS \ 1123 C(PRINT_PARENT, "print-parent"), \ 1124 C(SYM_OFFSET, "sym-offset"), \ 1125 C(SYM_ADDR, "sym-addr"), \ 1126 C(VERBOSE, "verbose"), \ 1127 C(RAW, "raw"), \ 1128 C(HEX, "hex"), \ 1129 C(BIN, "bin"), \ 1130 C(BLOCK, "block"), \ 1131 C(PRINTK, "trace_printk"), \ 1132 C(ANNOTATE, "annotate"), \ 1133 C(USERSTACKTRACE, "userstacktrace"), \ 1134 C(SYM_USEROBJ, "sym-userobj"), \ 1135 C(PRINTK_MSGONLY, "printk-msg-only"), \ 1136 C(CONTEXT_INFO, "context-info"), /* Print pid/cpu/time */ \ 1137 C(LATENCY_FMT, "latency-format"), \ 1138 C(RECORD_CMD, "record-cmd"), \ 1139 C(RECORD_TGID, "record-tgid"), \ 1140 C(OVERWRITE, "overwrite"), \ 1141 C(STOP_ON_FREE, "disable_on_free"), \ 1142 C(IRQ_INFO, "irq-info"), \ 1143 C(MARKERS, "markers"), \ 1144 C(EVENT_FORK, "event-fork"), \ 1145 FUNCTION_FLAGS \ 1146 FGRAPH_FLAGS \ 1147 STACK_FLAGS \ 1148 BRANCH_FLAGS 1149 1150 /* 1151 * By defining C, we can make TRACE_FLAGS a list of bit names 1152 * that will define the bits for the flag masks. 1153 */ 1154 #undef C 1155 #define C(a, b) TRACE_ITER_##a##_BIT 1156 1157 enum trace_iterator_bits { 1158 TRACE_FLAGS 1159 /* Make sure we don't go more than we have bits for */ 1160 TRACE_ITER_LAST_BIT 1161 }; 1162 1163 /* 1164 * By redefining C, we can make TRACE_FLAGS a list of masks that 1165 * use the bits as defined above. 1166 */ 1167 #undef C 1168 #define C(a, b) TRACE_ITER_##a = (1 << TRACE_ITER_##a##_BIT) 1169 1170 enum trace_iterator_flags { TRACE_FLAGS }; 1171 1172 /* 1173 * TRACE_ITER_SYM_MASK masks the options in trace_flags that 1174 * control the output of kernel symbols. 1175 */ 1176 #define TRACE_ITER_SYM_MASK \ 1177 (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR) 1178 1179 extern struct tracer nop_trace; 1180 1181 #ifdef CONFIG_BRANCH_TRACER 1182 extern int enable_branch_tracing(struct trace_array *tr); 1183 extern void disable_branch_tracing(void); 1184 static inline int trace_branch_enable(struct trace_array *tr) 1185 { 1186 if (tr->trace_flags & TRACE_ITER_BRANCH) 1187 return enable_branch_tracing(tr); 1188 return 0; 1189 } 1190 static inline void trace_branch_disable(void) 1191 { 1192 /* due to races, always disable */ 1193 disable_branch_tracing(); 1194 } 1195 #else 1196 static inline int trace_branch_enable(struct trace_array *tr) 1197 { 1198 return 0; 1199 } 1200 static inline void trace_branch_disable(void) 1201 { 1202 } 1203 #endif /* CONFIG_BRANCH_TRACER */ 1204 1205 /* set ring buffers to default size if not already done so */ 1206 int tracing_update_buffers(void); 1207 1208 struct ftrace_event_field { 1209 struct list_head link; 1210 const char *name; 1211 const char *type; 1212 int filter_type; 1213 int offset; 1214 int size; 1215 int is_signed; 1216 }; 1217 1218 struct prog_entry; 1219 1220 struct event_filter { 1221 struct prog_entry __rcu *prog; 1222 char *filter_string; 1223 }; 1224 1225 struct event_subsystem { 1226 struct list_head list; 1227 const char *name; 1228 struct event_filter *filter; 1229 int ref_count; 1230 }; 1231 1232 struct trace_subsystem_dir { 1233 struct list_head list; 1234 struct event_subsystem *subsystem; 1235 struct trace_array *tr; 1236 struct dentry *entry; 1237 int ref_count; 1238 int nr_events; 1239 }; 1240 1241 extern int call_filter_check_discard(struct trace_event_call *call, void *rec, 1242 struct ring_buffer *buffer, 1243 struct ring_buffer_event *event); 1244 1245 void trace_buffer_unlock_commit_regs(struct trace_array *tr, 1246 struct ring_buffer *buffer, 1247 struct ring_buffer_event *event, 1248 unsigned long flags, int pc, 1249 struct pt_regs *regs); 1250 1251 static inline void trace_buffer_unlock_commit(struct trace_array *tr, 1252 struct ring_buffer *buffer, 1253 struct ring_buffer_event *event, 1254 unsigned long flags, int pc) 1255 { 1256 trace_buffer_unlock_commit_regs(tr, buffer, event, flags, pc, NULL); 1257 } 1258 1259 DECLARE_PER_CPU(struct ring_buffer_event *, trace_buffered_event); 1260 DECLARE_PER_CPU(int, trace_buffered_event_cnt); 1261 void trace_buffered_event_disable(void); 1262 void trace_buffered_event_enable(void); 1263 1264 static inline void 1265 __trace_event_discard_commit(struct ring_buffer *buffer, 1266 struct ring_buffer_event *event) 1267 { 1268 if (this_cpu_read(trace_buffered_event) == event) { 1269 /* Simply release the temp buffer */ 1270 this_cpu_dec(trace_buffered_event_cnt); 1271 return; 1272 } 1273 ring_buffer_discard_commit(buffer, event); 1274 } 1275 1276 /* 1277 * Helper function for event_trigger_unlock_commit{_regs}(). 1278 * If there are event triggers attached to this event that requires 1279 * filtering against its fields, then they wil be called as the 1280 * entry already holds the field information of the current event. 1281 * 1282 * It also checks if the event should be discarded or not. 1283 * It is to be discarded if the event is soft disabled and the 1284 * event was only recorded to process triggers, or if the event 1285 * filter is active and this event did not match the filters. 1286 * 1287 * Returns true if the event is discarded, false otherwise. 1288 */ 1289 static inline bool 1290 __event_trigger_test_discard(struct trace_event_file *file, 1291 struct ring_buffer *buffer, 1292 struct ring_buffer_event *event, 1293 void *entry, 1294 enum event_trigger_type *tt) 1295 { 1296 unsigned long eflags = file->flags; 1297 1298 if (eflags & EVENT_FILE_FL_TRIGGER_COND) 1299 *tt = event_triggers_call(file, entry, event); 1300 1301 if (test_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &file->flags) || 1302 (unlikely(file->flags & EVENT_FILE_FL_FILTERED) && 1303 !filter_match_preds(file->filter, entry))) { 1304 __trace_event_discard_commit(buffer, event); 1305 return true; 1306 } 1307 1308 return false; 1309 } 1310 1311 /** 1312 * event_trigger_unlock_commit - handle triggers and finish event commit 1313 * @file: The file pointer assoctiated to the event 1314 * @buffer: The ring buffer that the event is being written to 1315 * @event: The event meta data in the ring buffer 1316 * @entry: The event itself 1317 * @irq_flags: The state of the interrupts at the start of the event 1318 * @pc: The state of the preempt count at the start of the event. 1319 * 1320 * This is a helper function to handle triggers that require data 1321 * from the event itself. It also tests the event against filters and 1322 * if the event is soft disabled and should be discarded. 1323 */ 1324 static inline void 1325 event_trigger_unlock_commit(struct trace_event_file *file, 1326 struct ring_buffer *buffer, 1327 struct ring_buffer_event *event, 1328 void *entry, unsigned long irq_flags, int pc) 1329 { 1330 enum event_trigger_type tt = ETT_NONE; 1331 1332 if (!__event_trigger_test_discard(file, buffer, event, entry, &tt)) 1333 trace_buffer_unlock_commit(file->tr, buffer, event, irq_flags, pc); 1334 1335 if (tt) 1336 event_triggers_post_call(file, tt); 1337 } 1338 1339 /** 1340 * event_trigger_unlock_commit_regs - handle triggers and finish event commit 1341 * @file: The file pointer assoctiated to the event 1342 * @buffer: The ring buffer that the event is being written to 1343 * @event: The event meta data in the ring buffer 1344 * @entry: The event itself 1345 * @irq_flags: The state of the interrupts at the start of the event 1346 * @pc: The state of the preempt count at the start of the event. 1347 * 1348 * This is a helper function to handle triggers that require data 1349 * from the event itself. It also tests the event against filters and 1350 * if the event is soft disabled and should be discarded. 1351 * 1352 * Same as event_trigger_unlock_commit() but calls 1353 * trace_buffer_unlock_commit_regs() instead of trace_buffer_unlock_commit(). 1354 */ 1355 static inline void 1356 event_trigger_unlock_commit_regs(struct trace_event_file *file, 1357 struct ring_buffer *buffer, 1358 struct ring_buffer_event *event, 1359 void *entry, unsigned long irq_flags, int pc, 1360 struct pt_regs *regs) 1361 { 1362 enum event_trigger_type tt = ETT_NONE; 1363 1364 if (!__event_trigger_test_discard(file, buffer, event, entry, &tt)) 1365 trace_buffer_unlock_commit_regs(file->tr, buffer, event, 1366 irq_flags, pc, regs); 1367 1368 if (tt) 1369 event_triggers_post_call(file, tt); 1370 } 1371 1372 #define FILTER_PRED_INVALID ((unsigned short)-1) 1373 #define FILTER_PRED_IS_RIGHT (1 << 15) 1374 #define FILTER_PRED_FOLD (1 << 15) 1375 1376 /* 1377 * The max preds is the size of unsigned short with 1378 * two flags at the MSBs. One bit is used for both the IS_RIGHT 1379 * and FOLD flags. The other is reserved. 1380 * 1381 * 2^14 preds is way more than enough. 1382 */ 1383 #define MAX_FILTER_PRED 16384 1384 1385 struct filter_pred; 1386 struct regex; 1387 1388 typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event); 1389 1390 typedef int (*regex_match_func)(char *str, struct regex *r, int len); 1391 1392 enum regex_type { 1393 MATCH_FULL = 0, 1394 MATCH_FRONT_ONLY, 1395 MATCH_MIDDLE_ONLY, 1396 MATCH_END_ONLY, 1397 MATCH_GLOB, 1398 }; 1399 1400 struct regex { 1401 char pattern[MAX_FILTER_STR_VAL]; 1402 int len; 1403 int field_len; 1404 regex_match_func match; 1405 }; 1406 1407 struct filter_pred { 1408 filter_pred_fn_t fn; 1409 u64 val; 1410 struct regex regex; 1411 unsigned short *ops; 1412 struct ftrace_event_field *field; 1413 int offset; 1414 int not; 1415 int op; 1416 }; 1417 1418 static inline bool is_string_field(struct ftrace_event_field *field) 1419 { 1420 return field->filter_type == FILTER_DYN_STRING || 1421 field->filter_type == FILTER_STATIC_STRING || 1422 field->filter_type == FILTER_PTR_STRING || 1423 field->filter_type == FILTER_COMM; 1424 } 1425 1426 static inline bool is_function_field(struct ftrace_event_field *field) 1427 { 1428 return field->filter_type == FILTER_TRACE_FN; 1429 } 1430 1431 extern enum regex_type 1432 filter_parse_regex(char *buff, int len, char **search, int *not); 1433 extern void print_event_filter(struct trace_event_file *file, 1434 struct trace_seq *s); 1435 extern int apply_event_filter(struct trace_event_file *file, 1436 char *filter_string); 1437 extern int apply_subsystem_event_filter(struct trace_subsystem_dir *dir, 1438 char *filter_string); 1439 extern void print_subsystem_event_filter(struct event_subsystem *system, 1440 struct trace_seq *s); 1441 extern int filter_assign_type(const char *type); 1442 extern int create_event_filter(struct trace_event_call *call, 1443 char *filter_str, bool set_str, 1444 struct event_filter **filterp); 1445 extern void free_event_filter(struct event_filter *filter); 1446 1447 struct ftrace_event_field * 1448 trace_find_event_field(struct trace_event_call *call, char *name); 1449 1450 extern void trace_event_enable_cmd_record(bool enable); 1451 extern void trace_event_enable_tgid_record(bool enable); 1452 1453 extern int event_trace_init(void); 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 extern struct trace_event_file *find_event_file(struct trace_array *tr, 1461 const char *system, 1462 const char *event); 1463 1464 static inline void *event_file_data(struct file *filp) 1465 { 1466 return READ_ONCE(file_inode(filp)->i_private); 1467 } 1468 1469 extern struct mutex event_mutex; 1470 extern struct list_head ftrace_events; 1471 1472 extern const struct file_operations event_trigger_fops; 1473 extern const struct file_operations event_hist_fops; 1474 1475 #ifdef CONFIG_HIST_TRIGGERS 1476 extern int register_trigger_hist_cmd(void); 1477 extern int register_trigger_hist_enable_disable_cmds(void); 1478 #else 1479 static inline int register_trigger_hist_cmd(void) { return 0; } 1480 static inline int register_trigger_hist_enable_disable_cmds(void) { return 0; } 1481 #endif 1482 1483 extern int register_trigger_cmds(void); 1484 extern void clear_event_triggers(struct trace_array *tr); 1485 1486 struct event_trigger_data { 1487 unsigned long count; 1488 int ref; 1489 struct event_trigger_ops *ops; 1490 struct event_command *cmd_ops; 1491 struct event_filter __rcu *filter; 1492 char *filter_str; 1493 void *private_data; 1494 bool paused; 1495 bool paused_tmp; 1496 struct list_head list; 1497 char *name; 1498 struct list_head named_list; 1499 struct event_trigger_data *named_data; 1500 }; 1501 1502 /* Avoid typos */ 1503 #define ENABLE_EVENT_STR "enable_event" 1504 #define DISABLE_EVENT_STR "disable_event" 1505 #define ENABLE_HIST_STR "enable_hist" 1506 #define DISABLE_HIST_STR "disable_hist" 1507 1508 struct enable_trigger_data { 1509 struct trace_event_file *file; 1510 bool enable; 1511 bool hist; 1512 }; 1513 1514 extern int event_enable_trigger_print(struct seq_file *m, 1515 struct event_trigger_ops *ops, 1516 struct event_trigger_data *data); 1517 extern void event_enable_trigger_free(struct event_trigger_ops *ops, 1518 struct event_trigger_data *data); 1519 extern int event_enable_trigger_func(struct event_command *cmd_ops, 1520 struct trace_event_file *file, 1521 char *glob, char *cmd, char *param); 1522 extern int event_enable_register_trigger(char *glob, 1523 struct event_trigger_ops *ops, 1524 struct event_trigger_data *data, 1525 struct trace_event_file *file); 1526 extern void event_enable_unregister_trigger(char *glob, 1527 struct event_trigger_ops *ops, 1528 struct event_trigger_data *test, 1529 struct trace_event_file *file); 1530 extern void trigger_data_free(struct event_trigger_data *data); 1531 extern int event_trigger_init(struct event_trigger_ops *ops, 1532 struct event_trigger_data *data); 1533 extern int trace_event_trigger_enable_disable(struct trace_event_file *file, 1534 int trigger_enable); 1535 extern void update_cond_flag(struct trace_event_file *file); 1536 extern void unregister_trigger(char *glob, struct event_trigger_ops *ops, 1537 struct event_trigger_data *test, 1538 struct trace_event_file *file); 1539 extern int set_trigger_filter(char *filter_str, 1540 struct event_trigger_data *trigger_data, 1541 struct trace_event_file *file); 1542 extern struct event_trigger_data *find_named_trigger(const char *name); 1543 extern bool is_named_trigger(struct event_trigger_data *test); 1544 extern int save_named_trigger(const char *name, 1545 struct event_trigger_data *data); 1546 extern void del_named_trigger(struct event_trigger_data *data); 1547 extern void pause_named_trigger(struct event_trigger_data *data); 1548 extern void unpause_named_trigger(struct event_trigger_data *data); 1549 extern void set_named_trigger_data(struct event_trigger_data *data, 1550 struct event_trigger_data *named_data); 1551 extern struct event_trigger_data * 1552 get_named_trigger_data(struct event_trigger_data *data); 1553 extern int register_event_command(struct event_command *cmd); 1554 extern int unregister_event_command(struct event_command *cmd); 1555 extern int register_trigger_hist_enable_disable_cmds(void); 1556 1557 /** 1558 * struct event_trigger_ops - callbacks for trace event triggers 1559 * 1560 * The methods in this structure provide per-event trigger hooks for 1561 * various trigger operations. 1562 * 1563 * All the methods below, except for @init() and @free(), must be 1564 * implemented. 1565 * 1566 * @func: The trigger 'probe' function called when the triggering 1567 * event occurs. The data passed into this callback is the data 1568 * that was supplied to the event_command @reg() function that 1569 * registered the trigger (see struct event_command) along with 1570 * the trace record, rec. 1571 * 1572 * @init: An optional initialization function called for the trigger 1573 * when the trigger is registered (via the event_command reg() 1574 * function). This can be used to perform per-trigger 1575 * initialization such as incrementing a per-trigger reference 1576 * count, for instance. This is usually implemented by the 1577 * generic utility function @event_trigger_init() (see 1578 * trace_event_triggers.c). 1579 * 1580 * @free: An optional de-initialization function called for the 1581 * trigger when the trigger is unregistered (via the 1582 * event_command @reg() function). This can be used to perform 1583 * per-trigger de-initialization such as decrementing a 1584 * per-trigger reference count and freeing corresponding trigger 1585 * data, for instance. This is usually implemented by the 1586 * generic utility function @event_trigger_free() (see 1587 * trace_event_triggers.c). 1588 * 1589 * @print: The callback function invoked to have the trigger print 1590 * itself. This is usually implemented by a wrapper function 1591 * that calls the generic utility function @event_trigger_print() 1592 * (see trace_event_triggers.c). 1593 */ 1594 struct event_trigger_ops { 1595 void (*func)(struct event_trigger_data *data, 1596 void *rec, 1597 struct ring_buffer_event *rbe); 1598 int (*init)(struct event_trigger_ops *ops, 1599 struct event_trigger_data *data); 1600 void (*free)(struct event_trigger_ops *ops, 1601 struct event_trigger_data *data); 1602 int (*print)(struct seq_file *m, 1603 struct event_trigger_ops *ops, 1604 struct event_trigger_data *data); 1605 }; 1606 1607 /** 1608 * struct event_command - callbacks and data members for event commands 1609 * 1610 * Event commands are invoked by users by writing the command name 1611 * into the 'trigger' file associated with a trace event. The 1612 * parameters associated with a specific invocation of an event 1613 * command are used to create an event trigger instance, which is 1614 * added to the list of trigger instances associated with that trace 1615 * event. When the event is hit, the set of triggers associated with 1616 * that event is invoked. 1617 * 1618 * The data members in this structure provide per-event command data 1619 * for various event commands. 1620 * 1621 * All the data members below, except for @post_trigger, must be set 1622 * for each event command. 1623 * 1624 * @name: The unique name that identifies the event command. This is 1625 * the name used when setting triggers via trigger files. 1626 * 1627 * @trigger_type: A unique id that identifies the event command 1628 * 'type'. This value has two purposes, the first to ensure that 1629 * only one trigger of the same type can be set at a given time 1630 * for a particular event e.g. it doesn't make sense to have both 1631 * a traceon and traceoff trigger attached to a single event at 1632 * the same time, so traceon and traceoff have the same type 1633 * though they have different names. The @trigger_type value is 1634 * also used as a bit value for deferring the actual trigger 1635 * action until after the current event is finished. Some 1636 * commands need to do this if they themselves log to the trace 1637 * buffer (see the @post_trigger() member below). @trigger_type 1638 * values are defined by adding new values to the trigger_type 1639 * enum in include/linux/trace_events.h. 1640 * 1641 * @flags: See the enum event_command_flags below. 1642 * 1643 * All the methods below, except for @set_filter() and @unreg_all(), 1644 * must be implemented. 1645 * 1646 * @func: The callback function responsible for parsing and 1647 * registering the trigger written to the 'trigger' file by the 1648 * user. It allocates the trigger instance and registers it with 1649 * the appropriate trace event. It makes use of the other 1650 * event_command callback functions to orchestrate this, and is 1651 * usually implemented by the generic utility function 1652 * @event_trigger_callback() (see trace_event_triggers.c). 1653 * 1654 * @reg: Adds the trigger to the list of triggers associated with the 1655 * event, and enables the event trigger itself, after 1656 * initializing it (via the event_trigger_ops @init() function). 1657 * This is also where commands can use the @trigger_type value to 1658 * make the decision as to whether or not multiple instances of 1659 * the trigger should be allowed. This is usually implemented by 1660 * the generic utility function @register_trigger() (see 1661 * trace_event_triggers.c). 1662 * 1663 * @unreg: Removes the trigger from the list of triggers associated 1664 * with the event, and disables the event trigger itself, after 1665 * initializing it (via the event_trigger_ops @free() function). 1666 * This is usually implemented by the generic utility function 1667 * @unregister_trigger() (see trace_event_triggers.c). 1668 * 1669 * @unreg_all: An optional function called to remove all the triggers 1670 * from the list of triggers associated with the event. Called 1671 * when a trigger file is opened in truncate mode. 1672 * 1673 * @set_filter: An optional function called to parse and set a filter 1674 * for the trigger. If no @set_filter() method is set for the 1675 * event command, filters set by the user for the command will be 1676 * ignored. This is usually implemented by the generic utility 1677 * function @set_trigger_filter() (see trace_event_triggers.c). 1678 * 1679 * @get_trigger_ops: The callback function invoked to retrieve the 1680 * event_trigger_ops implementation associated with the command. 1681 */ 1682 struct event_command { 1683 struct list_head list; 1684 char *name; 1685 enum event_trigger_type trigger_type; 1686 int flags; 1687 int (*func)(struct event_command *cmd_ops, 1688 struct trace_event_file *file, 1689 char *glob, char *cmd, char *params); 1690 int (*reg)(char *glob, 1691 struct event_trigger_ops *ops, 1692 struct event_trigger_data *data, 1693 struct trace_event_file *file); 1694 void (*unreg)(char *glob, 1695 struct event_trigger_ops *ops, 1696 struct event_trigger_data *data, 1697 struct trace_event_file *file); 1698 void (*unreg_all)(struct trace_event_file *file); 1699 int (*set_filter)(char *filter_str, 1700 struct event_trigger_data *data, 1701 struct trace_event_file *file); 1702 struct event_trigger_ops *(*get_trigger_ops)(char *cmd, char *param); 1703 }; 1704 1705 /** 1706 * enum event_command_flags - flags for struct event_command 1707 * 1708 * @POST_TRIGGER: A flag that says whether or not this command needs 1709 * to have its action delayed until after the current event has 1710 * been closed. Some triggers need to avoid being invoked while 1711 * an event is currently in the process of being logged, since 1712 * the trigger may itself log data into the trace buffer. Thus 1713 * we make sure the current event is committed before invoking 1714 * those triggers. To do that, the trigger invocation is split 1715 * in two - the first part checks the filter using the current 1716 * trace record; if a command has the @post_trigger flag set, it 1717 * sets a bit for itself in the return value, otherwise it 1718 * directly invokes the trigger. Once all commands have been 1719 * either invoked or set their return flag, the current record is 1720 * either committed or discarded. At that point, if any commands 1721 * have deferred their triggers, those commands are finally 1722 * invoked following the close of the current event. In other 1723 * words, if the event_trigger_ops @func() probe implementation 1724 * itself logs to the trace buffer, this flag should be set, 1725 * otherwise it can be left unspecified. 1726 * 1727 * @NEEDS_REC: A flag that says whether or not this command needs 1728 * access to the trace record in order to perform its function, 1729 * regardless of whether or not it has a filter associated with 1730 * it (filters make a trigger require access to the trace record 1731 * but are not always present). 1732 */ 1733 enum event_command_flags { 1734 EVENT_CMD_FL_POST_TRIGGER = 1, 1735 EVENT_CMD_FL_NEEDS_REC = 2, 1736 }; 1737 1738 static inline bool event_command_post_trigger(struct event_command *cmd_ops) 1739 { 1740 return cmd_ops->flags & EVENT_CMD_FL_POST_TRIGGER; 1741 } 1742 1743 static inline bool event_command_needs_rec(struct event_command *cmd_ops) 1744 { 1745 return cmd_ops->flags & EVENT_CMD_FL_NEEDS_REC; 1746 } 1747 1748 extern int trace_event_enable_disable(struct trace_event_file *file, 1749 int enable, int soft_disable); 1750 extern int tracing_alloc_snapshot(void); 1751 1752 extern const char *__start___trace_bprintk_fmt[]; 1753 extern const char *__stop___trace_bprintk_fmt[]; 1754 1755 extern const char *__start___tracepoint_str[]; 1756 extern const char *__stop___tracepoint_str[]; 1757 1758 void trace_printk_control(bool enabled); 1759 void trace_printk_init_buffers(void); 1760 void trace_printk_start_comm(void); 1761 int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set); 1762 int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled); 1763 1764 #define MAX_EVENT_NAME_LEN 64 1765 1766 extern int trace_run_command(const char *buf, int (*createfn)(int, char**)); 1767 extern ssize_t trace_parse_run_command(struct file *file, 1768 const char __user *buffer, size_t count, loff_t *ppos, 1769 int (*createfn)(int, char**)); 1770 1771 /* 1772 * Normal trace_printk() and friends allocates special buffers 1773 * to do the manipulation, as well as saves the print formats 1774 * into sections to display. But the trace infrastructure wants 1775 * to use these without the added overhead at the price of being 1776 * a bit slower (used mainly for warnings, where we don't care 1777 * about performance). The internal_trace_puts() is for such 1778 * a purpose. 1779 */ 1780 #define internal_trace_puts(str) __trace_puts(_THIS_IP_, str, strlen(str)) 1781 1782 #undef FTRACE_ENTRY 1783 #define FTRACE_ENTRY(call, struct_name, id, tstruct, print, filter) \ 1784 extern struct trace_event_call \ 1785 __aligned(4) event_##call; 1786 #undef FTRACE_ENTRY_DUP 1787 #define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print, filter) \ 1788 FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print), \ 1789 filter) 1790 #undef FTRACE_ENTRY_PACKED 1791 #define FTRACE_ENTRY_PACKED(call, struct_name, id, tstruct, print, filter) \ 1792 FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print), \ 1793 filter) 1794 1795 #include "trace_entries.h" 1796 1797 #if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER) 1798 int perf_ftrace_event_register(struct trace_event_call *call, 1799 enum trace_reg type, void *data); 1800 #else 1801 #define perf_ftrace_event_register NULL 1802 #endif 1803 1804 #ifdef CONFIG_FTRACE_SYSCALLS 1805 void init_ftrace_syscalls(void); 1806 const char *get_syscall_name(int syscall); 1807 #else 1808 static inline void init_ftrace_syscalls(void) { } 1809 static inline const char *get_syscall_name(int syscall) 1810 { 1811 return NULL; 1812 } 1813 #endif 1814 1815 #ifdef CONFIG_EVENT_TRACING 1816 void trace_event_init(void); 1817 void trace_event_eval_update(struct trace_eval_map **map, int len); 1818 #else 1819 static inline void __init trace_event_init(void) { } 1820 static inline void trace_event_eval_update(struct trace_eval_map **map, int len) { } 1821 #endif 1822 1823 #ifdef CONFIG_TRACER_SNAPSHOT 1824 void tracing_snapshot_instance(struct trace_array *tr); 1825 int tracing_alloc_snapshot_instance(struct trace_array *tr); 1826 #else 1827 static inline void tracing_snapshot_instance(struct trace_array *tr) { } 1828 static inline int tracing_alloc_snapshot_instance(struct trace_array *tr) 1829 { 1830 return 0; 1831 } 1832 #endif 1833 1834 extern struct trace_iterator *tracepoint_print_iter; 1835 1836 #endif /* _LINUX_KERNEL_TRACE_H */ 1837