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