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/trace.h> 15 #include <linux/hw_breakpoint.h> 16 #include <linux/trace_seq.h> 17 #include <linux/trace_events.h> 18 #include <linux/compiler.h> 19 #include <linux/glob.h> 20 #include <linux/irq_work.h> 21 #include <linux/workqueue.h> 22 #include <linux/ctype.h> 23 #include <linux/once_lite.h> 24 #include <linux/ftrace_regs.h> 25 26 #include "pid_list.h" 27 28 #ifdef CONFIG_FTRACE_SYSCALLS 29 #include <asm/unistd.h> /* For NR_syscalls */ 30 #include <asm/syscall.h> /* some archs define it here */ 31 #endif 32 33 #define TRACE_MODE_WRITE 0640 34 #define TRACE_MODE_READ 0440 35 36 enum trace_type { 37 __TRACE_FIRST_TYPE = 0, 38 39 TRACE_FN, 40 TRACE_CTX, 41 TRACE_WAKE, 42 TRACE_STACK, 43 TRACE_PRINT, 44 TRACE_BPRINT, 45 TRACE_MMIO_RW, 46 TRACE_MMIO_MAP, 47 TRACE_BRANCH, 48 TRACE_GRAPH_RET, 49 TRACE_GRAPH_ENT, 50 TRACE_GRAPH_RETADDR_ENT, 51 TRACE_USER_STACK, 52 TRACE_BLK, 53 TRACE_BPUTS, 54 TRACE_HWLAT, 55 TRACE_OSNOISE, 56 TRACE_TIMERLAT, 57 TRACE_RAW_DATA, 58 TRACE_FUNC_REPEATS, 59 60 __TRACE_LAST_TYPE, 61 }; 62 63 64 #undef __field 65 #define __field(type, item) type item; 66 67 #undef __field_fn 68 #define __field_fn(type, item) type item; 69 70 #undef __field_struct 71 #define __field_struct(type, item) __field(type, item) 72 73 #undef __field_desc 74 #define __field_desc(type, container, item) 75 76 #undef __field_packed 77 #define __field_packed(type, container, item) 78 79 #undef __array 80 #define __array(type, item, size) type item[size]; 81 82 /* 83 * For backward compatibility, older user space expects to see the 84 * kernel_stack event with a fixed size caller field. But today the fix 85 * size is ignored by the kernel, and the real structure is dynamic. 86 * Expose to user space: "unsigned long caller[8];" but the real structure 87 * will be "unsigned long caller[] __counted_by(size)" 88 */ 89 #undef __stack_array 90 #define __stack_array(type, item, size, field) type item[] __counted_by(field); 91 92 #undef __array_desc 93 #define __array_desc(type, container, item, size) 94 95 #undef __dynamic_array 96 #define __dynamic_array(type, item) type item[]; 97 98 #undef __rel_dynamic_array 99 #define __rel_dynamic_array(type, item) type item[]; 100 101 #undef F_STRUCT 102 #define F_STRUCT(args...) args 103 104 #undef FTRACE_ENTRY 105 #define FTRACE_ENTRY(name, struct_name, id, tstruct, print) \ 106 struct struct_name { \ 107 struct trace_entry ent; \ 108 tstruct \ 109 } 110 111 #undef FTRACE_ENTRY_DUP 112 #define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk) 113 114 #undef FTRACE_ENTRY_REG 115 #define FTRACE_ENTRY_REG(name, struct_name, id, tstruct, print, regfn) \ 116 FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print)) 117 118 #undef FTRACE_ENTRY_PACKED 119 #define FTRACE_ENTRY_PACKED(name, struct_name, id, tstruct, print) \ 120 FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print)) __packed 121 122 #include "trace_entries.h" 123 124 /* Use this for memory failure errors */ 125 #define MEM_FAIL(condition, fmt, ...) \ 126 DO_ONCE_LITE_IF(condition, pr_err, "ERROR: " fmt, ##__VA_ARGS__) 127 128 #define FAULT_STRING "(fault)" 129 130 #define HIST_STACKTRACE_DEPTH 16 131 #define HIST_STACKTRACE_SIZE (HIST_STACKTRACE_DEPTH * sizeof(unsigned long)) 132 #define HIST_STACKTRACE_SKIP 5 133 134 /* 135 * syscalls are special, and need special handling, this is why 136 * they are not included in trace_entries.h 137 */ 138 struct syscall_trace_enter { 139 struct trace_entry ent; 140 int nr; 141 unsigned long args[]; 142 }; 143 144 struct syscall_trace_exit { 145 struct trace_entry ent; 146 int nr; 147 long ret; 148 }; 149 150 struct kprobe_trace_entry_head { 151 struct trace_entry ent; 152 unsigned long ip; 153 }; 154 155 struct eprobe_trace_entry_head { 156 struct trace_entry ent; 157 }; 158 159 struct kretprobe_trace_entry_head { 160 struct trace_entry ent; 161 unsigned long func; 162 unsigned long ret_ip; 163 }; 164 165 struct fentry_trace_entry_head { 166 struct trace_entry ent; 167 unsigned long ip; 168 }; 169 170 struct fexit_trace_entry_head { 171 struct trace_entry ent; 172 unsigned long func; 173 unsigned long ret_ip; 174 }; 175 176 #define TRACE_BUF_SIZE 1024 177 178 struct trace_array; 179 180 /* 181 * The CPU trace array - it consists of thousands of trace entries 182 * plus some other descriptor data: (for example which task started 183 * the trace, etc.) 184 */ 185 struct trace_array_cpu { 186 atomic_t disabled; 187 void *buffer_page; /* ring buffer spare */ 188 189 unsigned long entries; 190 unsigned long saved_latency; 191 unsigned long critical_start; 192 unsigned long critical_end; 193 unsigned long critical_sequence; 194 unsigned long nice; 195 unsigned long policy; 196 unsigned long rt_priority; 197 unsigned long skipped_entries; 198 u64 preempt_timestamp; 199 pid_t pid; 200 kuid_t uid; 201 char comm[TASK_COMM_LEN]; 202 203 #ifdef CONFIG_FUNCTION_TRACER 204 int ftrace_ignore_pid; 205 #endif 206 bool ignore_pid; 207 }; 208 209 struct tracer; 210 struct trace_option_dentry; 211 212 struct array_buffer { 213 struct trace_array *tr; 214 struct trace_buffer *buffer; 215 struct trace_array_cpu __percpu *data; 216 u64 time_start; 217 int cpu; 218 }; 219 220 #define TRACE_FLAGS_MAX_SIZE 32 221 222 struct trace_options { 223 struct tracer *tracer; 224 struct trace_option_dentry *topts; 225 }; 226 227 struct trace_pid_list *trace_pid_list_alloc(void); 228 void trace_pid_list_free(struct trace_pid_list *pid_list); 229 bool trace_pid_list_is_set(struct trace_pid_list *pid_list, unsigned int pid); 230 int trace_pid_list_set(struct trace_pid_list *pid_list, unsigned int pid); 231 int trace_pid_list_clear(struct trace_pid_list *pid_list, unsigned int pid); 232 int trace_pid_list_first(struct trace_pid_list *pid_list, unsigned int *pid); 233 int trace_pid_list_next(struct trace_pid_list *pid_list, unsigned int pid, 234 unsigned int *next); 235 236 enum { 237 TRACE_PIDS = BIT(0), 238 TRACE_NO_PIDS = BIT(1), 239 }; 240 241 static inline bool pid_type_enabled(int type, struct trace_pid_list *pid_list, 242 struct trace_pid_list *no_pid_list) 243 { 244 /* Return true if the pid list in type has pids */ 245 return ((type & TRACE_PIDS) && pid_list) || 246 ((type & TRACE_NO_PIDS) && no_pid_list); 247 } 248 249 static inline bool still_need_pid_events(int type, struct trace_pid_list *pid_list, 250 struct trace_pid_list *no_pid_list) 251 { 252 /* 253 * Turning off what is in @type, return true if the "other" 254 * pid list, still has pids in it. 255 */ 256 return (!(type & TRACE_PIDS) && pid_list) || 257 (!(type & TRACE_NO_PIDS) && no_pid_list); 258 } 259 260 typedef bool (*cond_update_fn_t)(struct trace_array *tr, void *cond_data); 261 262 /** 263 * struct cond_snapshot - conditional snapshot data and callback 264 * 265 * The cond_snapshot structure encapsulates a callback function and 266 * data associated with the snapshot for a given tracing instance. 267 * 268 * When a snapshot is taken conditionally, by invoking 269 * tracing_snapshot_cond(tr, cond_data), the cond_data passed in is 270 * passed in turn to the cond_snapshot.update() function. That data 271 * can be compared by the update() implementation with the cond_data 272 * contained within the struct cond_snapshot instance associated with 273 * the trace_array. Because the tr->max_lock is held throughout the 274 * update() call, the update() function can directly retrieve the 275 * cond_snapshot and cond_data associated with the per-instance 276 * snapshot associated with the trace_array. 277 * 278 * The cond_snapshot.update() implementation can save data to be 279 * associated with the snapshot if it decides to, and returns 'true' 280 * in that case, or it returns 'false' if the conditional snapshot 281 * shouldn't be taken. 282 * 283 * The cond_snapshot instance is created and associated with the 284 * user-defined cond_data by tracing_cond_snapshot_enable(). 285 * Likewise, the cond_snapshot instance is destroyed and is no longer 286 * associated with the trace instance by 287 * tracing_cond_snapshot_disable(). 288 * 289 * The method below is required. 290 * 291 * @update: When a conditional snapshot is invoked, the update() 292 * callback function is invoked with the tr->max_lock held. The 293 * update() implementation signals whether or not to actually 294 * take the snapshot, by returning 'true' if so, 'false' if no 295 * snapshot should be taken. Because the max_lock is held for 296 * the duration of update(), the implementation is safe to 297 * directly retrieved and save any implementation data it needs 298 * to in association with the snapshot. 299 */ 300 struct cond_snapshot { 301 void *cond_data; 302 cond_update_fn_t update; 303 }; 304 305 /* 306 * struct trace_func_repeats - used to keep track of the consecutive 307 * (on the same CPU) calls of a single function. 308 */ 309 struct trace_func_repeats { 310 unsigned long ip; 311 unsigned long parent_ip; 312 unsigned long count; 313 u64 ts_last_call; 314 }; 315 316 struct trace_module_delta { 317 struct rcu_head rcu; 318 long delta[]; 319 }; 320 321 /* 322 * The trace array - an array of per-CPU trace arrays. This is the 323 * highest level data structure that individual tracers deal with. 324 * They have on/off state as well: 325 */ 326 struct trace_array { 327 struct list_head list; 328 char *name; 329 struct array_buffer array_buffer; 330 #ifdef CONFIG_TRACER_MAX_TRACE 331 /* 332 * The max_buffer is used to snapshot the trace when a maximum 333 * latency is reached, or when the user initiates a snapshot. 334 * Some tracers will use this to store a maximum trace while 335 * it continues examining live traces. 336 * 337 * The buffers for the max_buffer are set up the same as the array_buffer 338 * When a snapshot is taken, the buffer of the max_buffer is swapped 339 * with the buffer of the array_buffer and the buffers are reset for 340 * the array_buffer so the tracing can continue. 341 */ 342 struct array_buffer max_buffer; 343 bool allocated_snapshot; 344 spinlock_t snapshot_trigger_lock; 345 unsigned int snapshot; 346 unsigned long max_latency; 347 #ifdef CONFIG_FSNOTIFY 348 struct dentry *d_max_latency; 349 struct work_struct fsnotify_work; 350 struct irq_work fsnotify_irqwork; 351 #endif 352 #endif 353 /* The below is for memory mapped ring buffer */ 354 unsigned int mapped; 355 unsigned long range_addr_start; 356 unsigned long range_addr_size; 357 char *range_name; 358 long text_delta; 359 struct trace_module_delta *module_delta; 360 void *scratch; /* pointer in persistent memory */ 361 int scratch_size; 362 363 int buffer_disabled; 364 365 struct trace_pid_list __rcu *filtered_pids; 366 struct trace_pid_list __rcu *filtered_no_pids; 367 /* 368 * max_lock is used to protect the swapping of buffers 369 * when taking a max snapshot. The buffers themselves are 370 * protected by per_cpu spinlocks. But the action of the swap 371 * needs its own lock. 372 * 373 * This is defined as a arch_spinlock_t in order to help 374 * with performance when lockdep debugging is enabled. 375 * 376 * It is also used in other places outside the update_max_tr 377 * so it needs to be defined outside of the 378 * CONFIG_TRACER_MAX_TRACE. 379 */ 380 arch_spinlock_t max_lock; 381 #ifdef CONFIG_FTRACE_SYSCALLS 382 int sys_refcount_enter; 383 int sys_refcount_exit; 384 struct trace_event_file __rcu *enter_syscall_files[NR_syscalls]; 385 struct trace_event_file __rcu *exit_syscall_files[NR_syscalls]; 386 #endif 387 int stop_count; 388 int clock_id; 389 int nr_topts; 390 bool clear_trace; 391 int buffer_percent; 392 unsigned int n_err_log_entries; 393 struct tracer *current_trace; 394 unsigned int trace_flags; 395 unsigned char trace_flags_index[TRACE_FLAGS_MAX_SIZE]; 396 unsigned int flags; 397 raw_spinlock_t start_lock; 398 const char *system_names; 399 struct list_head err_log; 400 struct dentry *dir; 401 struct dentry *options; 402 struct dentry *percpu_dir; 403 struct eventfs_inode *event_dir; 404 struct trace_options *topts; 405 struct list_head systems; 406 struct list_head events; 407 struct trace_event_file *trace_marker_file; 408 cpumask_var_t tracing_cpumask; /* only trace on set CPUs */ 409 /* one per_cpu trace_pipe can be opened by only one user */ 410 cpumask_var_t pipe_cpumask; 411 int ref; 412 int trace_ref; 413 #ifdef CONFIG_MODULES 414 struct list_head mod_events; 415 #endif 416 #ifdef CONFIG_FUNCTION_TRACER 417 struct ftrace_ops *ops; 418 struct trace_pid_list __rcu *function_pids; 419 struct trace_pid_list __rcu *function_no_pids; 420 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 421 struct fgraph_ops *gops; 422 #endif 423 #ifdef CONFIG_DYNAMIC_FTRACE 424 /* All of these are protected by the ftrace_lock */ 425 struct list_head func_probes; 426 struct list_head mod_trace; 427 struct list_head mod_notrace; 428 #endif 429 /* function tracing enabled */ 430 int function_enabled; 431 #endif 432 int no_filter_buffering_ref; 433 struct list_head hist_vars; 434 #ifdef CONFIG_TRACER_SNAPSHOT 435 struct cond_snapshot *cond_snapshot; 436 #endif 437 struct trace_func_repeats __percpu *last_func_repeats; 438 /* 439 * On boot up, the ring buffer is set to the minimum size, so that 440 * we do not waste memory on systems that are not using tracing. 441 */ 442 bool ring_buffer_expanded; 443 }; 444 445 enum { 446 TRACE_ARRAY_FL_GLOBAL = BIT(0), 447 TRACE_ARRAY_FL_BOOT = BIT(1), 448 TRACE_ARRAY_FL_LAST_BOOT = BIT(2), 449 TRACE_ARRAY_FL_MOD_INIT = BIT(3), 450 }; 451 452 #ifdef CONFIG_MODULES 453 bool module_exists(const char *module); 454 #else 455 static inline bool module_exists(const char *module) 456 { 457 return false; 458 } 459 #endif 460 461 extern struct list_head ftrace_trace_arrays; 462 463 extern struct mutex trace_types_lock; 464 465 extern int trace_array_get(struct trace_array *tr); 466 extern int tracing_check_open_get_tr(struct trace_array *tr); 467 extern struct trace_array *trace_array_find(const char *instance); 468 extern struct trace_array *trace_array_find_get(const char *instance); 469 470 extern u64 tracing_event_time_stamp(struct trace_buffer *buffer, struct ring_buffer_event *rbe); 471 extern int tracing_set_filter_buffering(struct trace_array *tr, bool set); 472 extern int tracing_set_clock(struct trace_array *tr, const char *clockstr); 473 474 extern bool trace_clock_in_ns(struct trace_array *tr); 475 476 extern unsigned long trace_adjust_address(struct trace_array *tr, unsigned long addr); 477 478 /* 479 * The global tracer (top) should be the first trace array added, 480 * but we check the flag anyway. 481 */ 482 static inline struct trace_array *top_trace_array(void) 483 { 484 struct trace_array *tr; 485 486 if (list_empty(&ftrace_trace_arrays)) 487 return NULL; 488 489 tr = list_entry(ftrace_trace_arrays.prev, 490 typeof(*tr), list); 491 WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL)); 492 return tr; 493 } 494 495 #define FTRACE_CMP_TYPE(var, type) \ 496 __builtin_types_compatible_p(typeof(var), type *) 497 498 #undef IF_ASSIGN 499 #define IF_ASSIGN(var, entry, etype, id) \ 500 if (FTRACE_CMP_TYPE(var, etype)) { \ 501 var = (typeof(var))(entry); \ 502 WARN_ON(id != 0 && (entry)->type != id); \ 503 break; \ 504 } 505 506 /* Will cause compile errors if type is not found. */ 507 extern void __ftrace_bad_type(void); 508 509 /* 510 * The trace_assign_type is a verifier that the entry type is 511 * the same as the type being assigned. To add new types simply 512 * add a line with the following format: 513 * 514 * IF_ASSIGN(var, ent, type, id); 515 * 516 * Where "type" is the trace type that includes the trace_entry 517 * as the "ent" item. And "id" is the trace identifier that is 518 * used in the trace_type enum. 519 * 520 * If the type can have more than one id, then use zero. 521 */ 522 #define trace_assign_type(var, ent) \ 523 do { \ 524 IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN); \ 525 IF_ASSIGN(var, ent, struct ctx_switch_entry, 0); \ 526 IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK); \ 527 IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\ 528 IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT); \ 529 IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT); \ 530 IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS); \ 531 IF_ASSIGN(var, ent, struct hwlat_entry, TRACE_HWLAT); \ 532 IF_ASSIGN(var, ent, struct osnoise_entry, TRACE_OSNOISE);\ 533 IF_ASSIGN(var, ent, struct timerlat_entry, TRACE_TIMERLAT);\ 534 IF_ASSIGN(var, ent, struct raw_data_entry, TRACE_RAW_DATA);\ 535 IF_ASSIGN(var, ent, struct trace_mmiotrace_rw, \ 536 TRACE_MMIO_RW); \ 537 IF_ASSIGN(var, ent, struct trace_mmiotrace_map, \ 538 TRACE_MMIO_MAP); \ 539 IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \ 540 IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry, \ 541 TRACE_GRAPH_ENT); \ 542 IF_ASSIGN(var, ent, struct fgraph_retaddr_ent_entry,\ 543 TRACE_GRAPH_RETADDR_ENT); \ 544 IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry, \ 545 TRACE_GRAPH_RET); \ 546 IF_ASSIGN(var, ent, struct func_repeats_entry, \ 547 TRACE_FUNC_REPEATS); \ 548 __ftrace_bad_type(); \ 549 } while (0) 550 551 /* 552 * An option specific to a tracer. This is a boolean value. 553 * The bit is the bit index that sets its value on the 554 * flags value in struct tracer_flags. 555 */ 556 struct tracer_opt { 557 const char *name; /* Will appear on the trace_options file */ 558 u32 bit; /* Mask assigned in val field in tracer_flags */ 559 }; 560 561 /* 562 * The set of specific options for a tracer. Your tracer 563 * have to set the initial value of the flags val. 564 */ 565 struct tracer_flags { 566 u32 val; 567 struct tracer_opt *opts; 568 struct tracer *trace; 569 }; 570 571 /* Makes more easy to define a tracer opt */ 572 #define TRACER_OPT(s, b) .name = #s, .bit = b 573 574 575 struct trace_option_dentry { 576 struct tracer_opt *opt; 577 struct tracer_flags *flags; 578 struct trace_array *tr; 579 struct dentry *entry; 580 }; 581 582 /** 583 * struct tracer - a specific tracer and its callbacks to interact with tracefs 584 * @name: the name chosen to select it on the available_tracers file 585 * @init: called when one switches to this tracer (echo name > current_tracer) 586 * @reset: called when one switches to another tracer 587 * @start: called when tracing is unpaused (echo 1 > tracing_on) 588 * @stop: called when tracing is paused (echo 0 > tracing_on) 589 * @update_thresh: called when tracing_thresh is updated 590 * @open: called when the trace file is opened 591 * @pipe_open: called when the trace_pipe file is opened 592 * @close: called when the trace file is released 593 * @pipe_close: called when the trace_pipe file is released 594 * @read: override the default read callback on trace_pipe 595 * @splice_read: override the default splice_read callback on trace_pipe 596 * @selftest: selftest to run on boot (see trace_selftest.c) 597 * @print_headers: override the first lines that describe your columns 598 * @print_line: callback that prints a trace 599 * @set_flag: signals one of your private flags changed (trace_options file) 600 * @flags: your private flags 601 */ 602 struct tracer { 603 const char *name; 604 int (*init)(struct trace_array *tr); 605 void (*reset)(struct trace_array *tr); 606 void (*start)(struct trace_array *tr); 607 void (*stop)(struct trace_array *tr); 608 int (*update_thresh)(struct trace_array *tr); 609 void (*open)(struct trace_iterator *iter); 610 void (*pipe_open)(struct trace_iterator *iter); 611 void (*close)(struct trace_iterator *iter); 612 void (*pipe_close)(struct trace_iterator *iter); 613 ssize_t (*read)(struct trace_iterator *iter, 614 struct file *filp, char __user *ubuf, 615 size_t cnt, loff_t *ppos); 616 ssize_t (*splice_read)(struct trace_iterator *iter, 617 struct file *filp, 618 loff_t *ppos, 619 struct pipe_inode_info *pipe, 620 size_t len, 621 unsigned int flags); 622 #ifdef CONFIG_FTRACE_STARTUP_TEST 623 int (*selftest)(struct tracer *trace, 624 struct trace_array *tr); 625 #endif 626 void (*print_header)(struct seq_file *m); 627 enum print_line_t (*print_line)(struct trace_iterator *iter); 628 /* If you handled the flag setting, return 0 */ 629 int (*set_flag)(struct trace_array *tr, 630 u32 old_flags, u32 bit, int set); 631 /* Return 0 if OK with change, else return non-zero */ 632 int (*flag_changed)(struct trace_array *tr, 633 u32 mask, int set); 634 struct tracer *next; 635 struct tracer_flags *flags; 636 int enabled; 637 bool print_max; 638 bool allow_instances; 639 #ifdef CONFIG_TRACER_MAX_TRACE 640 bool use_max_tr; 641 #endif 642 /* True if tracer cannot be enabled in kernel param */ 643 bool noboot; 644 }; 645 646 static inline struct ring_buffer_iter * 647 trace_buffer_iter(struct trace_iterator *iter, int cpu) 648 { 649 return iter->buffer_iter ? iter->buffer_iter[cpu] : NULL; 650 } 651 652 int tracer_init(struct tracer *t, struct trace_array *tr); 653 int tracing_is_enabled(void); 654 void tracing_reset_online_cpus(struct array_buffer *buf); 655 void tracing_reset_all_online_cpus(void); 656 void tracing_reset_all_online_cpus_unlocked(void); 657 int tracing_open_generic(struct inode *inode, struct file *filp); 658 int tracing_open_generic_tr(struct inode *inode, struct file *filp); 659 int tracing_release_generic_tr(struct inode *inode, struct file *file); 660 int tracing_open_file_tr(struct inode *inode, struct file *filp); 661 int tracing_release_file_tr(struct inode *inode, struct file *filp); 662 int tracing_single_release_file_tr(struct inode *inode, struct file *filp); 663 bool tracing_is_disabled(void); 664 bool tracer_tracing_is_on(struct trace_array *tr); 665 void tracer_tracing_on(struct trace_array *tr); 666 void tracer_tracing_off(struct trace_array *tr); 667 struct dentry *trace_create_file(const char *name, 668 umode_t mode, 669 struct dentry *parent, 670 void *data, 671 const struct file_operations *fops); 672 673 int tracing_init_dentry(void); 674 675 struct ring_buffer_event; 676 677 struct ring_buffer_event * 678 trace_buffer_lock_reserve(struct trace_buffer *buffer, 679 int type, 680 unsigned long len, 681 unsigned int trace_ctx); 682 683 int ring_buffer_meta_seq_init(struct file *file, struct trace_buffer *buffer, int cpu); 684 685 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr, 686 struct trace_array_cpu *data); 687 688 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, 689 int *ent_cpu, u64 *ent_ts); 690 691 void trace_buffer_unlock_commit_nostack(struct trace_buffer *buffer, 692 struct ring_buffer_event *event); 693 694 bool trace_is_tracepoint_string(const char *str); 695 const char *trace_event_format(struct trace_iterator *iter, const char *fmt); 696 char *trace_iter_expand_format(struct trace_iterator *iter); 697 bool ignore_event(struct trace_iterator *iter); 698 699 int trace_empty(struct trace_iterator *iter); 700 701 void *trace_find_next_entry_inc(struct trace_iterator *iter); 702 703 void trace_init_global_iter(struct trace_iterator *iter); 704 705 void tracing_iter_reset(struct trace_iterator *iter, int cpu); 706 707 unsigned long trace_total_entries_cpu(struct trace_array *tr, int cpu); 708 unsigned long trace_total_entries(struct trace_array *tr); 709 710 void trace_function(struct trace_array *tr, 711 unsigned long ip, 712 unsigned long parent_ip, 713 unsigned int trace_ctx, 714 struct ftrace_regs *regs); 715 void trace_graph_function(struct trace_array *tr, 716 unsigned long ip, 717 unsigned long parent_ip, 718 unsigned int trace_ctx); 719 void trace_latency_header(struct seq_file *m); 720 void trace_default_header(struct seq_file *m); 721 void print_trace_header(struct seq_file *m, struct trace_iterator *iter); 722 723 void trace_graph_return(struct ftrace_graph_ret *trace, struct fgraph_ops *gops, 724 struct ftrace_regs *fregs); 725 int trace_graph_entry(struct ftrace_graph_ent *trace, struct fgraph_ops *gops, 726 struct ftrace_regs *fregs); 727 728 void tracing_start_cmdline_record(void); 729 void tracing_stop_cmdline_record(void); 730 void tracing_start_tgid_record(void); 731 void tracing_stop_tgid_record(void); 732 733 int register_tracer(struct tracer *type); 734 int is_tracing_stopped(void); 735 736 loff_t tracing_lseek(struct file *file, loff_t offset, int whence); 737 738 extern cpumask_var_t __read_mostly tracing_buffer_mask; 739 740 #define for_each_tracing_cpu(cpu) \ 741 for_each_cpu(cpu, tracing_buffer_mask) 742 743 extern unsigned long nsecs_to_usecs(unsigned long nsecs); 744 745 extern unsigned long tracing_thresh; 746 747 /* PID filtering */ 748 749 bool trace_find_filtered_pid(struct trace_pid_list *filtered_pids, 750 pid_t search_pid); 751 bool trace_ignore_this_task(struct trace_pid_list *filtered_pids, 752 struct trace_pid_list *filtered_no_pids, 753 struct task_struct *task); 754 void trace_filter_add_remove_task(struct trace_pid_list *pid_list, 755 struct task_struct *self, 756 struct task_struct *task); 757 void *trace_pid_next(struct trace_pid_list *pid_list, void *v, loff_t *pos); 758 void *trace_pid_start(struct trace_pid_list *pid_list, loff_t *pos); 759 int trace_pid_show(struct seq_file *m, void *v); 760 int trace_pid_write(struct trace_pid_list *filtered_pids, 761 struct trace_pid_list **new_pid_list, 762 const char __user *ubuf, size_t cnt); 763 764 #ifdef CONFIG_TRACER_MAX_TRACE 765 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu, 766 void *cond_data); 767 void update_max_tr_single(struct trace_array *tr, 768 struct task_struct *tsk, int cpu); 769 770 #ifdef CONFIG_FSNOTIFY 771 #define LATENCY_FS_NOTIFY 772 #endif 773 #endif /* CONFIG_TRACER_MAX_TRACE */ 774 775 #ifdef LATENCY_FS_NOTIFY 776 void latency_fsnotify(struct trace_array *tr); 777 #else 778 static inline void latency_fsnotify(struct trace_array *tr) { } 779 #endif 780 781 #ifdef CONFIG_STACKTRACE 782 void __trace_stack(struct trace_array *tr, unsigned int trace_ctx, int skip); 783 #else 784 static inline void __trace_stack(struct trace_array *tr, unsigned int trace_ctx, 785 int skip) 786 { 787 } 788 #endif /* CONFIG_STACKTRACE */ 789 790 void trace_last_func_repeats(struct trace_array *tr, 791 struct trace_func_repeats *last_info, 792 unsigned int trace_ctx); 793 794 extern u64 ftrace_now(int cpu); 795 796 extern void trace_find_cmdline(int pid, char comm[]); 797 extern int trace_find_tgid(int pid); 798 extern void trace_event_follow_fork(struct trace_array *tr, bool enable); 799 800 extern int trace_events_enabled(struct trace_array *tr, const char *system); 801 802 #ifdef CONFIG_DYNAMIC_FTRACE 803 extern unsigned long ftrace_update_tot_cnt; 804 extern unsigned long ftrace_number_of_pages; 805 extern unsigned long ftrace_number_of_groups; 806 extern u64 ftrace_update_time; 807 extern u64 ftrace_total_mod_time; 808 void ftrace_init_trace_array(struct trace_array *tr); 809 #else 810 static inline void ftrace_init_trace_array(struct trace_array *tr) { } 811 #endif 812 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func 813 extern int DYN_FTRACE_TEST_NAME(void); 814 #define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2 815 extern int DYN_FTRACE_TEST_NAME2(void); 816 817 extern void trace_set_ring_buffer_expanded(struct trace_array *tr); 818 extern bool tracing_selftest_disabled; 819 820 #ifdef CONFIG_FTRACE_STARTUP_TEST 821 extern void __init disable_tracing_selftest(const char *reason); 822 823 extern int trace_selftest_startup_function(struct tracer *trace, 824 struct trace_array *tr); 825 extern int trace_selftest_startup_function_graph(struct tracer *trace, 826 struct trace_array *tr); 827 extern int trace_selftest_startup_irqsoff(struct tracer *trace, 828 struct trace_array *tr); 829 extern int trace_selftest_startup_preemptoff(struct tracer *trace, 830 struct trace_array *tr); 831 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace, 832 struct trace_array *tr); 833 extern int trace_selftest_startup_wakeup(struct tracer *trace, 834 struct trace_array *tr); 835 extern int trace_selftest_startup_nop(struct tracer *trace, 836 struct trace_array *tr); 837 extern int trace_selftest_startup_branch(struct tracer *trace, 838 struct trace_array *tr); 839 /* 840 * Tracer data references selftest functions that only occur 841 * on boot up. These can be __init functions. Thus, when selftests 842 * are enabled, then the tracers need to reference __init functions. 843 */ 844 #define __tracer_data __refdata 845 #else 846 static inline void __init disable_tracing_selftest(const char *reason) 847 { 848 } 849 /* Tracers are seldom changed. Optimize when selftests are disabled. */ 850 #define __tracer_data __read_mostly 851 #endif /* CONFIG_FTRACE_STARTUP_TEST */ 852 853 extern void *head_page(struct trace_array_cpu *data); 854 extern unsigned long long ns2usecs(u64 nsec); 855 856 __printf(2, 0) 857 int trace_vbprintk(unsigned long ip, const char *fmt, va_list args); 858 __printf(2, 0) 859 int trace_vprintk(unsigned long ip, const char *fmt, va_list args); 860 __printf(3, 0) 861 int trace_array_vprintk(struct trace_array *tr, 862 unsigned long ip, const char *fmt, va_list args); 863 __printf(3, 4) 864 int trace_array_printk_buf(struct trace_buffer *buffer, 865 unsigned long ip, const char *fmt, ...); 866 void trace_printk_seq(struct trace_seq *s); 867 enum print_line_t print_trace_line(struct trace_iterator *iter); 868 869 extern char trace_find_mark(unsigned long long duration); 870 871 struct ftrace_hash; 872 873 struct ftrace_mod_load { 874 struct list_head list; 875 char *func; 876 char *module; 877 int enable; 878 }; 879 880 enum { 881 FTRACE_HASH_FL_MOD = (1 << 0), 882 }; 883 884 struct ftrace_hash { 885 unsigned long size_bits; 886 struct hlist_head *buckets; 887 unsigned long count; 888 unsigned long flags; 889 struct rcu_head rcu; 890 }; 891 892 struct ftrace_func_entry * 893 ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip); 894 895 static __always_inline bool ftrace_hash_empty(struct ftrace_hash *hash) 896 { 897 return !hash || !(hash->count || (hash->flags & FTRACE_HASH_FL_MOD)); 898 } 899 900 /* Standard output formatting function used for function return traces */ 901 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 902 903 /* Flag options */ 904 #define TRACE_GRAPH_PRINT_OVERRUN 0x1 905 #define TRACE_GRAPH_PRINT_CPU 0x2 906 #define TRACE_GRAPH_PRINT_OVERHEAD 0x4 907 #define TRACE_GRAPH_PRINT_PROC 0x8 908 #define TRACE_GRAPH_PRINT_DURATION 0x10 909 #define TRACE_GRAPH_PRINT_ABS_TIME 0x20 910 #define TRACE_GRAPH_PRINT_REL_TIME 0x40 911 #define TRACE_GRAPH_PRINT_IRQS 0x80 912 #define TRACE_GRAPH_PRINT_TAIL 0x100 913 #define TRACE_GRAPH_SLEEP_TIME 0x200 914 #define TRACE_GRAPH_GRAPH_TIME 0x400 915 #define TRACE_GRAPH_PRINT_RETVAL 0x800 916 #define TRACE_GRAPH_PRINT_RETVAL_HEX 0x1000 917 #define TRACE_GRAPH_PRINT_RETADDR 0x2000 918 #define TRACE_GRAPH_ARGS 0x4000 919 #define TRACE_GRAPH_PRINT_FILL_SHIFT 28 920 #define TRACE_GRAPH_PRINT_FILL_MASK (0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT) 921 922 extern void ftrace_graph_sleep_time_control(bool enable); 923 924 #ifdef CONFIG_FUNCTION_PROFILER 925 extern void ftrace_graph_graph_time_control(bool enable); 926 #else 927 static inline void ftrace_graph_graph_time_control(bool enable) { } 928 #endif 929 930 extern enum print_line_t 931 print_graph_function_flags(struct trace_iterator *iter, u32 flags); 932 extern void print_graph_headers_flags(struct seq_file *s, u32 flags); 933 extern void 934 trace_print_graph_duration(unsigned long long duration, struct trace_seq *s); 935 extern void graph_trace_open(struct trace_iterator *iter); 936 extern void graph_trace_close(struct trace_iterator *iter); 937 extern int __trace_graph_entry(struct trace_array *tr, 938 struct ftrace_graph_ent *trace, 939 unsigned int trace_ctx); 940 extern int __trace_graph_retaddr_entry(struct trace_array *tr, 941 struct ftrace_graph_ent *trace, 942 unsigned int trace_ctx, 943 unsigned long retaddr); 944 extern void __trace_graph_return(struct trace_array *tr, 945 struct ftrace_graph_ret *trace, 946 unsigned int trace_ctx, 947 u64 calltime, u64 rettime); 948 949 extern void init_array_fgraph_ops(struct trace_array *tr, struct ftrace_ops *ops); 950 extern int allocate_fgraph_ops(struct trace_array *tr, struct ftrace_ops *ops); 951 extern void free_fgraph_ops(struct trace_array *tr); 952 953 enum { 954 TRACE_GRAPH_FL = 1, 955 956 /* 957 * In the very unlikely case that an interrupt came in 958 * at a start of graph tracing, and we want to trace 959 * the function in that interrupt, the depth can be greater 960 * than zero, because of the preempted start of a previous 961 * trace. In an even more unlikely case, depth could be 2 962 * if a softirq interrupted the start of graph tracing, 963 * followed by an interrupt preempting a start of graph 964 * tracing in the softirq, and depth can even be 3 965 * if an NMI came in at the start of an interrupt function 966 * that preempted a softirq start of a function that 967 * preempted normal context!!!! Luckily, it can't be 968 * greater than 3, so the next two bits are a mask 969 * of what the depth is when we set TRACE_GRAPH_FL 970 */ 971 972 TRACE_GRAPH_DEPTH_START_BIT, 973 TRACE_GRAPH_DEPTH_END_BIT, 974 975 /* 976 * To implement set_graph_notrace, if this bit is set, we ignore 977 * function graph tracing of called functions, until the return 978 * function is called to clear it. 979 */ 980 TRACE_GRAPH_NOTRACE_BIT, 981 }; 982 983 #define TRACE_GRAPH_NOTRACE (1 << TRACE_GRAPH_NOTRACE_BIT) 984 985 static inline unsigned long ftrace_graph_depth(unsigned long *task_var) 986 { 987 return (*task_var >> TRACE_GRAPH_DEPTH_START_BIT) & 3; 988 } 989 990 static inline void ftrace_graph_set_depth(unsigned long *task_var, int depth) 991 { 992 *task_var &= ~(3 << TRACE_GRAPH_DEPTH_START_BIT); 993 *task_var |= (depth & 3) << TRACE_GRAPH_DEPTH_START_BIT; 994 } 995 996 #ifdef CONFIG_DYNAMIC_FTRACE 997 extern struct ftrace_hash __rcu *ftrace_graph_hash; 998 extern struct ftrace_hash __rcu *ftrace_graph_notrace_hash; 999 1000 static inline int 1001 ftrace_graph_addr(unsigned long *task_var, struct ftrace_graph_ent *trace) 1002 { 1003 unsigned long addr = trace->func; 1004 int ret = 0; 1005 struct ftrace_hash *hash; 1006 1007 preempt_disable_notrace(); 1008 1009 /* 1010 * Have to open code "rcu_dereference_sched()" because the 1011 * function graph tracer can be called when RCU is not 1012 * "watching". 1013 * Protected with schedule_on_each_cpu(ftrace_sync) 1014 */ 1015 hash = rcu_dereference_protected(ftrace_graph_hash, !preemptible()); 1016 1017 if (ftrace_hash_empty(hash)) { 1018 ret = 1; 1019 goto out; 1020 } 1021 1022 if (ftrace_lookup_ip(hash, addr)) { 1023 /* 1024 * This needs to be cleared on the return functions 1025 * when the depth is zero. 1026 */ 1027 *task_var |= TRACE_GRAPH_FL; 1028 ftrace_graph_set_depth(task_var, trace->depth); 1029 1030 /* 1031 * If no irqs are to be traced, but a set_graph_function 1032 * is set, and called by an interrupt handler, we still 1033 * want to trace it. 1034 */ 1035 if (in_hardirq()) 1036 trace_recursion_set(TRACE_IRQ_BIT); 1037 else 1038 trace_recursion_clear(TRACE_IRQ_BIT); 1039 ret = 1; 1040 } 1041 1042 out: 1043 preempt_enable_notrace(); 1044 return ret; 1045 } 1046 1047 static inline void 1048 ftrace_graph_addr_finish(struct fgraph_ops *gops, struct ftrace_graph_ret *trace) 1049 { 1050 unsigned long *task_var = fgraph_get_task_var(gops); 1051 1052 if ((*task_var & TRACE_GRAPH_FL) && 1053 trace->depth == ftrace_graph_depth(task_var)) 1054 *task_var &= ~TRACE_GRAPH_FL; 1055 } 1056 1057 static inline int ftrace_graph_notrace_addr(unsigned long addr) 1058 { 1059 int ret = 0; 1060 struct ftrace_hash *notrace_hash; 1061 1062 preempt_disable_notrace(); 1063 1064 /* 1065 * Have to open code "rcu_dereference_sched()" because the 1066 * function graph tracer can be called when RCU is not 1067 * "watching". 1068 * Protected with schedule_on_each_cpu(ftrace_sync) 1069 */ 1070 notrace_hash = rcu_dereference_protected(ftrace_graph_notrace_hash, 1071 !preemptible()); 1072 1073 if (ftrace_lookup_ip(notrace_hash, addr)) 1074 ret = 1; 1075 1076 preempt_enable_notrace(); 1077 return ret; 1078 } 1079 #else 1080 static inline int ftrace_graph_addr(unsigned long *task_var, struct ftrace_graph_ent *trace) 1081 { 1082 return 1; 1083 } 1084 1085 static inline int ftrace_graph_notrace_addr(unsigned long addr) 1086 { 1087 return 0; 1088 } 1089 static inline void ftrace_graph_addr_finish(struct fgraph_ops *gops, struct ftrace_graph_ret *trace) 1090 { } 1091 #endif /* CONFIG_DYNAMIC_FTRACE */ 1092 1093 extern unsigned int fgraph_max_depth; 1094 extern bool fgraph_sleep_time; 1095 1096 static inline bool 1097 ftrace_graph_ignore_func(struct fgraph_ops *gops, struct ftrace_graph_ent *trace) 1098 { 1099 unsigned long *task_var = fgraph_get_task_var(gops); 1100 1101 /* trace it when it is-nested-in or is a function enabled. */ 1102 return !((*task_var & TRACE_GRAPH_FL) || 1103 ftrace_graph_addr(task_var, trace)) || 1104 (trace->depth < 0) || 1105 (fgraph_max_depth && trace->depth >= fgraph_max_depth); 1106 } 1107 1108 void fgraph_init_ops(struct ftrace_ops *dst_ops, 1109 struct ftrace_ops *src_ops); 1110 1111 #else /* CONFIG_FUNCTION_GRAPH_TRACER */ 1112 static inline enum print_line_t 1113 print_graph_function_flags(struct trace_iterator *iter, u32 flags) 1114 { 1115 return TRACE_TYPE_UNHANDLED; 1116 } 1117 static inline void free_fgraph_ops(struct trace_array *tr) { } 1118 /* ftrace_ops may not be defined */ 1119 #define init_array_fgraph_ops(tr, ops) do { } while (0) 1120 #define allocate_fgraph_ops(tr, ops) ({ 0; }) 1121 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ 1122 1123 extern struct list_head ftrace_pids; 1124 1125 #ifdef CONFIG_FUNCTION_TRACER 1126 1127 #define FTRACE_PID_IGNORE -1 1128 #define FTRACE_PID_TRACE -2 1129 1130 struct ftrace_func_command { 1131 struct list_head list; 1132 char *name; 1133 int (*func)(struct trace_array *tr, 1134 struct ftrace_hash *hash, 1135 char *func, char *cmd, 1136 char *params, int enable); 1137 }; 1138 extern bool ftrace_filter_param __initdata; 1139 static inline int ftrace_trace_task(struct trace_array *tr) 1140 { 1141 return this_cpu_read(tr->array_buffer.data->ftrace_ignore_pid) != 1142 FTRACE_PID_IGNORE; 1143 } 1144 extern int ftrace_is_dead(void); 1145 int ftrace_create_function_files(struct trace_array *tr, 1146 struct dentry *parent); 1147 void ftrace_destroy_function_files(struct trace_array *tr); 1148 int ftrace_allocate_ftrace_ops(struct trace_array *tr); 1149 void ftrace_free_ftrace_ops(struct trace_array *tr); 1150 void ftrace_init_global_array_ops(struct trace_array *tr); 1151 struct trace_array *trace_get_global_array(void); 1152 void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func); 1153 void ftrace_reset_array_ops(struct trace_array *tr); 1154 void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer); 1155 void ftrace_init_tracefs_toplevel(struct trace_array *tr, 1156 struct dentry *d_tracer); 1157 void ftrace_clear_pids(struct trace_array *tr); 1158 int init_function_trace(void); 1159 void ftrace_pid_follow_fork(struct trace_array *tr, bool enable); 1160 #else 1161 static inline int ftrace_trace_task(struct trace_array *tr) 1162 { 1163 return 1; 1164 } 1165 static inline int ftrace_is_dead(void) { return 0; } 1166 static inline int 1167 ftrace_create_function_files(struct trace_array *tr, 1168 struct dentry *parent) 1169 { 1170 return 0; 1171 } 1172 static inline int ftrace_allocate_ftrace_ops(struct trace_array *tr) 1173 { 1174 return 0; 1175 } 1176 static inline void ftrace_free_ftrace_ops(struct trace_array *tr) { } 1177 static inline void ftrace_destroy_function_files(struct trace_array *tr) { } 1178 static inline __init void 1179 ftrace_init_global_array_ops(struct trace_array *tr) { } 1180 static inline void ftrace_reset_array_ops(struct trace_array *tr) { } 1181 static inline void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d) { } 1182 static inline void ftrace_init_tracefs_toplevel(struct trace_array *tr, struct dentry *d) { } 1183 static inline void ftrace_clear_pids(struct trace_array *tr) { } 1184 static inline int init_function_trace(void) { return 0; } 1185 static inline void ftrace_pid_follow_fork(struct trace_array *tr, bool enable) { } 1186 /* ftace_func_t type is not defined, use macro instead of static inline */ 1187 #define ftrace_init_array_ops(tr, func) do { } while (0) 1188 #endif /* CONFIG_FUNCTION_TRACER */ 1189 1190 #if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE) 1191 1192 struct ftrace_probe_ops { 1193 void (*func)(unsigned long ip, 1194 unsigned long parent_ip, 1195 struct trace_array *tr, 1196 struct ftrace_probe_ops *ops, 1197 void *data); 1198 int (*init)(struct ftrace_probe_ops *ops, 1199 struct trace_array *tr, 1200 unsigned long ip, void *init_data, 1201 void **data); 1202 void (*free)(struct ftrace_probe_ops *ops, 1203 struct trace_array *tr, 1204 unsigned long ip, void *data); 1205 int (*print)(struct seq_file *m, 1206 unsigned long ip, 1207 struct ftrace_probe_ops *ops, 1208 void *data); 1209 }; 1210 1211 struct ftrace_func_mapper; 1212 typedef int (*ftrace_mapper_func)(void *data); 1213 1214 struct ftrace_func_mapper *allocate_ftrace_func_mapper(void); 1215 void **ftrace_func_mapper_find_ip(struct ftrace_func_mapper *mapper, 1216 unsigned long ip); 1217 int ftrace_func_mapper_add_ip(struct ftrace_func_mapper *mapper, 1218 unsigned long ip, void *data); 1219 void *ftrace_func_mapper_remove_ip(struct ftrace_func_mapper *mapper, 1220 unsigned long ip); 1221 void free_ftrace_func_mapper(struct ftrace_func_mapper *mapper, 1222 ftrace_mapper_func free_func); 1223 1224 extern int 1225 register_ftrace_function_probe(char *glob, struct trace_array *tr, 1226 struct ftrace_probe_ops *ops, void *data); 1227 extern int 1228 unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr, 1229 struct ftrace_probe_ops *ops); 1230 extern void clear_ftrace_function_probes(struct trace_array *tr); 1231 1232 int register_ftrace_command(struct ftrace_func_command *cmd); 1233 int unregister_ftrace_command(struct ftrace_func_command *cmd); 1234 1235 void ftrace_create_filter_files(struct ftrace_ops *ops, 1236 struct dentry *parent); 1237 void ftrace_destroy_filter_files(struct ftrace_ops *ops); 1238 1239 extern int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf, 1240 int len, int reset); 1241 extern int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf, 1242 int len, int reset); 1243 #else 1244 struct ftrace_func_command; 1245 1246 static inline __init int register_ftrace_command(struct ftrace_func_command *cmd) 1247 { 1248 return -EINVAL; 1249 } 1250 static inline __init int unregister_ftrace_command(char *cmd_name) 1251 { 1252 return -EINVAL; 1253 } 1254 static inline void clear_ftrace_function_probes(struct trace_array *tr) 1255 { 1256 } 1257 1258 /* 1259 * The ops parameter passed in is usually undefined. 1260 * This must be a macro. 1261 */ 1262 #define ftrace_create_filter_files(ops, parent) do { } while (0) 1263 #define ftrace_destroy_filter_files(ops) do { } while (0) 1264 #endif /* CONFIG_FUNCTION_TRACER && CONFIG_DYNAMIC_FTRACE */ 1265 1266 bool ftrace_event_is_function(struct trace_event_call *call); 1267 1268 /* 1269 * struct trace_parser - servers for reading the user input separated by spaces 1270 * @cont: set if the input is not complete - no final space char was found 1271 * @buffer: holds the parsed user input 1272 * @idx: user input length 1273 * @size: buffer size 1274 */ 1275 struct trace_parser { 1276 bool cont; 1277 char *buffer; 1278 unsigned idx; 1279 unsigned size; 1280 }; 1281 1282 static inline bool trace_parser_loaded(struct trace_parser *parser) 1283 { 1284 return (parser->idx != 0); 1285 } 1286 1287 static inline bool trace_parser_cont(struct trace_parser *parser) 1288 { 1289 return parser->cont; 1290 } 1291 1292 static inline void trace_parser_clear(struct trace_parser *parser) 1293 { 1294 parser->cont = false; 1295 parser->idx = 0; 1296 } 1297 1298 extern int trace_parser_get_init(struct trace_parser *parser, int size); 1299 extern void trace_parser_put(struct trace_parser *parser); 1300 extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf, 1301 size_t cnt, loff_t *ppos); 1302 1303 /* 1304 * Only create function graph options if function graph is configured. 1305 */ 1306 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 1307 # define FGRAPH_FLAGS \ 1308 C(DISPLAY_GRAPH, "display-graph"), 1309 #else 1310 # define FGRAPH_FLAGS 1311 #endif 1312 1313 #ifdef CONFIG_BRANCH_TRACER 1314 # define BRANCH_FLAGS \ 1315 C(BRANCH, "branch"), 1316 #else 1317 # define BRANCH_FLAGS 1318 #endif 1319 1320 #ifdef CONFIG_FUNCTION_TRACER 1321 # define FUNCTION_FLAGS \ 1322 C(FUNCTION, "function-trace"), \ 1323 C(FUNC_FORK, "function-fork"), 1324 # define FUNCTION_DEFAULT_FLAGS TRACE_ITER_FUNCTION 1325 #else 1326 # define FUNCTION_FLAGS 1327 # define FUNCTION_DEFAULT_FLAGS 0UL 1328 # define TRACE_ITER_FUNC_FORK 0UL 1329 #endif 1330 1331 #ifdef CONFIG_STACKTRACE 1332 # define STACK_FLAGS \ 1333 C(STACKTRACE, "stacktrace"), 1334 #else 1335 # define STACK_FLAGS 1336 #endif 1337 1338 /* 1339 * trace_iterator_flags is an enumeration that defines bit 1340 * positions into trace_flags that controls the output. 1341 * 1342 * NOTE: These bits must match the trace_options array in 1343 * trace.c (this macro guarantees it). 1344 */ 1345 #define TRACE_FLAGS \ 1346 C(PRINT_PARENT, "print-parent"), \ 1347 C(SYM_OFFSET, "sym-offset"), \ 1348 C(SYM_ADDR, "sym-addr"), \ 1349 C(VERBOSE, "verbose"), \ 1350 C(RAW, "raw"), \ 1351 C(HEX, "hex"), \ 1352 C(BIN, "bin"), \ 1353 C(BLOCK, "block"), \ 1354 C(FIELDS, "fields"), \ 1355 C(PRINTK, "trace_printk"), \ 1356 C(ANNOTATE, "annotate"), \ 1357 C(USERSTACKTRACE, "userstacktrace"), \ 1358 C(SYM_USEROBJ, "sym-userobj"), \ 1359 C(PRINTK_MSGONLY, "printk-msg-only"), \ 1360 C(CONTEXT_INFO, "context-info"), /* Print pid/cpu/time */ \ 1361 C(LATENCY_FMT, "latency-format"), \ 1362 C(RECORD_CMD, "record-cmd"), \ 1363 C(RECORD_TGID, "record-tgid"), \ 1364 C(OVERWRITE, "overwrite"), \ 1365 C(STOP_ON_FREE, "disable_on_free"), \ 1366 C(IRQ_INFO, "irq-info"), \ 1367 C(MARKERS, "markers"), \ 1368 C(EVENT_FORK, "event-fork"), \ 1369 C(TRACE_PRINTK, "trace_printk_dest"), \ 1370 C(PAUSE_ON_TRACE, "pause-on-trace"), \ 1371 C(HASH_PTR, "hash-ptr"), /* Print hashed pointer */ \ 1372 FUNCTION_FLAGS \ 1373 FGRAPH_FLAGS \ 1374 STACK_FLAGS \ 1375 BRANCH_FLAGS 1376 1377 /* 1378 * By defining C, we can make TRACE_FLAGS a list of bit names 1379 * that will define the bits for the flag masks. 1380 */ 1381 #undef C 1382 #define C(a, b) TRACE_ITER_##a##_BIT 1383 1384 enum trace_iterator_bits { 1385 TRACE_FLAGS 1386 /* Make sure we don't go more than we have bits for */ 1387 TRACE_ITER_LAST_BIT 1388 }; 1389 1390 /* 1391 * By redefining C, we can make TRACE_FLAGS a list of masks that 1392 * use the bits as defined above. 1393 */ 1394 #undef C 1395 #define C(a, b) TRACE_ITER_##a = (1 << TRACE_ITER_##a##_BIT) 1396 1397 enum trace_iterator_flags { TRACE_FLAGS }; 1398 1399 /* 1400 * TRACE_ITER_SYM_MASK masks the options in trace_flags that 1401 * control the output of kernel symbols. 1402 */ 1403 #define TRACE_ITER_SYM_MASK \ 1404 (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR) 1405 1406 extern struct tracer nop_trace; 1407 1408 #ifdef CONFIG_BRANCH_TRACER 1409 extern int enable_branch_tracing(struct trace_array *tr); 1410 extern void disable_branch_tracing(void); 1411 static inline int trace_branch_enable(struct trace_array *tr) 1412 { 1413 if (tr->trace_flags & TRACE_ITER_BRANCH) 1414 return enable_branch_tracing(tr); 1415 return 0; 1416 } 1417 static inline void trace_branch_disable(void) 1418 { 1419 /* due to races, always disable */ 1420 disable_branch_tracing(); 1421 } 1422 #else 1423 static inline int trace_branch_enable(struct trace_array *tr) 1424 { 1425 return 0; 1426 } 1427 static inline void trace_branch_disable(void) 1428 { 1429 } 1430 #endif /* CONFIG_BRANCH_TRACER */ 1431 1432 /* set ring buffers to default size if not already done so */ 1433 int tracing_update_buffers(struct trace_array *tr); 1434 1435 union trace_synth_field { 1436 u8 as_u8; 1437 u16 as_u16; 1438 u32 as_u32; 1439 u64 as_u64; 1440 struct trace_dynamic_info as_dynamic; 1441 }; 1442 1443 struct ftrace_event_field { 1444 struct list_head link; 1445 const char *name; 1446 const char *type; 1447 int filter_type; 1448 int offset; 1449 int size; 1450 unsigned int is_signed:1; 1451 unsigned int needs_test:1; 1452 int len; 1453 }; 1454 1455 struct prog_entry; 1456 1457 struct event_filter { 1458 struct prog_entry __rcu *prog; 1459 char *filter_string; 1460 }; 1461 1462 struct event_subsystem { 1463 struct list_head list; 1464 const char *name; 1465 struct event_filter *filter; 1466 int ref_count; 1467 }; 1468 1469 struct trace_subsystem_dir { 1470 struct list_head list; 1471 struct event_subsystem *subsystem; 1472 struct trace_array *tr; 1473 struct eventfs_inode *ei; 1474 int ref_count; 1475 int nr_events; 1476 }; 1477 1478 void trace_buffer_unlock_commit_regs(struct trace_array *tr, 1479 struct trace_buffer *buffer, 1480 struct ring_buffer_event *event, 1481 unsigned int trcace_ctx, 1482 struct pt_regs *regs); 1483 1484 static inline void trace_buffer_unlock_commit(struct trace_array *tr, 1485 struct trace_buffer *buffer, 1486 struct ring_buffer_event *event, 1487 unsigned int trace_ctx) 1488 { 1489 trace_buffer_unlock_commit_regs(tr, buffer, event, trace_ctx, NULL); 1490 } 1491 1492 DECLARE_PER_CPU(bool, trace_taskinfo_save); 1493 int trace_save_cmdline(struct task_struct *tsk); 1494 int trace_create_savedcmd(void); 1495 int trace_alloc_tgid_map(void); 1496 void trace_free_saved_cmdlines_buffer(void); 1497 1498 extern const struct file_operations tracing_saved_cmdlines_fops; 1499 extern const struct file_operations tracing_saved_tgids_fops; 1500 extern const struct file_operations tracing_saved_cmdlines_size_fops; 1501 1502 DECLARE_PER_CPU(struct ring_buffer_event *, trace_buffered_event); 1503 DECLARE_PER_CPU(int, trace_buffered_event_cnt); 1504 void trace_buffered_event_disable(void); 1505 void trace_buffered_event_enable(void); 1506 1507 void early_enable_events(struct trace_array *tr, char *buf, bool disable_first); 1508 1509 static inline void 1510 __trace_event_discard_commit(struct trace_buffer *buffer, 1511 struct ring_buffer_event *event) 1512 { 1513 if (this_cpu_read(trace_buffered_event) == event) { 1514 /* Simply release the temp buffer and enable preemption */ 1515 this_cpu_dec(trace_buffered_event_cnt); 1516 preempt_enable_notrace(); 1517 return; 1518 } 1519 /* ring_buffer_discard_commit() enables preemption */ 1520 ring_buffer_discard_commit(buffer, event); 1521 } 1522 1523 /* 1524 * Helper function for event_trigger_unlock_commit{_regs}(). 1525 * If there are event triggers attached to this event that requires 1526 * filtering against its fields, then they will be called as the 1527 * entry already holds the field information of the current event. 1528 * 1529 * It also checks if the event should be discarded or not. 1530 * It is to be discarded if the event is soft disabled and the 1531 * event was only recorded to process triggers, or if the event 1532 * filter is active and this event did not match the filters. 1533 * 1534 * Returns true if the event is discarded, false otherwise. 1535 */ 1536 static inline bool 1537 __event_trigger_test_discard(struct trace_event_file *file, 1538 struct trace_buffer *buffer, 1539 struct ring_buffer_event *event, 1540 void *entry, 1541 enum event_trigger_type *tt) 1542 { 1543 unsigned long eflags = file->flags; 1544 1545 if (eflags & EVENT_FILE_FL_TRIGGER_COND) 1546 *tt = event_triggers_call(file, buffer, entry, event); 1547 1548 if (likely(!(file->flags & (EVENT_FILE_FL_SOFT_DISABLED | 1549 EVENT_FILE_FL_FILTERED | 1550 EVENT_FILE_FL_PID_FILTER)))) 1551 return false; 1552 1553 if (file->flags & EVENT_FILE_FL_SOFT_DISABLED) 1554 goto discard; 1555 1556 if (file->flags & EVENT_FILE_FL_FILTERED && 1557 !filter_match_preds(file->filter, entry)) 1558 goto discard; 1559 1560 if ((file->flags & EVENT_FILE_FL_PID_FILTER) && 1561 trace_event_ignore_this_pid(file)) 1562 goto discard; 1563 1564 return false; 1565 discard: 1566 __trace_event_discard_commit(buffer, event); 1567 return true; 1568 } 1569 1570 /** 1571 * event_trigger_unlock_commit - handle triggers and finish event commit 1572 * @file: The file pointer associated with the event 1573 * @buffer: The ring buffer that the event is being written to 1574 * @event: The event meta data in the ring buffer 1575 * @entry: The event itself 1576 * @trace_ctx: The tracing context flags. 1577 * 1578 * This is a helper function to handle triggers that require data 1579 * from the event itself. It also tests the event against filters and 1580 * if the event is soft disabled and should be discarded. 1581 */ 1582 static inline void 1583 event_trigger_unlock_commit(struct trace_event_file *file, 1584 struct trace_buffer *buffer, 1585 struct ring_buffer_event *event, 1586 void *entry, unsigned int trace_ctx) 1587 { 1588 enum event_trigger_type tt = ETT_NONE; 1589 1590 if (!__event_trigger_test_discard(file, buffer, event, entry, &tt)) 1591 trace_buffer_unlock_commit(file->tr, buffer, event, trace_ctx); 1592 1593 if (tt) 1594 event_triggers_post_call(file, tt); 1595 } 1596 1597 #define FILTER_PRED_INVALID ((unsigned short)-1) 1598 #define FILTER_PRED_IS_RIGHT (1 << 15) 1599 #define FILTER_PRED_FOLD (1 << 15) 1600 1601 /* 1602 * The max preds is the size of unsigned short with 1603 * two flags at the MSBs. One bit is used for both the IS_RIGHT 1604 * and FOLD flags. The other is reserved. 1605 * 1606 * 2^14 preds is way more than enough. 1607 */ 1608 #define MAX_FILTER_PRED 16384 1609 1610 struct filter_pred; 1611 struct regex; 1612 1613 typedef int (*regex_match_func)(char *str, struct regex *r, int len); 1614 1615 enum regex_type { 1616 MATCH_FULL = 0, 1617 MATCH_FRONT_ONLY, 1618 MATCH_MIDDLE_ONLY, 1619 MATCH_END_ONLY, 1620 MATCH_GLOB, 1621 MATCH_INDEX, 1622 }; 1623 1624 struct regex { 1625 char pattern[MAX_FILTER_STR_VAL]; 1626 int len; 1627 int field_len; 1628 regex_match_func match; 1629 }; 1630 1631 static inline bool is_string_field(struct ftrace_event_field *field) 1632 { 1633 return field->filter_type == FILTER_DYN_STRING || 1634 field->filter_type == FILTER_RDYN_STRING || 1635 field->filter_type == FILTER_STATIC_STRING || 1636 field->filter_type == FILTER_PTR_STRING || 1637 field->filter_type == FILTER_COMM; 1638 } 1639 1640 static inline bool is_function_field(struct ftrace_event_field *field) 1641 { 1642 return field->filter_type == FILTER_TRACE_FN; 1643 } 1644 1645 extern enum regex_type 1646 filter_parse_regex(char *buff, int len, char **search, int *not); 1647 extern void print_event_filter(struct trace_event_file *file, 1648 struct trace_seq *s); 1649 extern int apply_event_filter(struct trace_event_file *file, 1650 char *filter_string); 1651 extern int apply_subsystem_event_filter(struct trace_subsystem_dir *dir, 1652 char *filter_string); 1653 extern void print_subsystem_event_filter(struct event_subsystem *system, 1654 struct trace_seq *s); 1655 extern int filter_assign_type(const char *type); 1656 extern int create_event_filter(struct trace_array *tr, 1657 struct trace_event_call *call, 1658 char *filter_str, bool set_str, 1659 struct event_filter **filterp); 1660 extern void free_event_filter(struct event_filter *filter); 1661 1662 struct ftrace_event_field * 1663 trace_find_event_field(struct trace_event_call *call, char *name); 1664 1665 extern void trace_event_enable_cmd_record(bool enable); 1666 extern void trace_event_enable_tgid_record(bool enable); 1667 1668 extern int event_trace_init(void); 1669 extern int init_events(void); 1670 extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr); 1671 extern int event_trace_del_tracer(struct trace_array *tr); 1672 extern void __trace_early_add_events(struct trace_array *tr); 1673 1674 extern struct trace_event_file *__find_event_file(struct trace_array *tr, 1675 const char *system, 1676 const char *event); 1677 extern struct trace_event_file *find_event_file(struct trace_array *tr, 1678 const char *system, 1679 const char *event); 1680 1681 static inline void *event_file_data(struct file *filp) 1682 { 1683 return READ_ONCE(file_inode(filp)->i_private); 1684 } 1685 1686 extern struct mutex event_mutex; 1687 extern struct list_head ftrace_events; 1688 1689 /* 1690 * When the trace_event_file is the filp->i_private pointer, 1691 * it must be taken under the event_mutex lock, and then checked 1692 * if the EVENT_FILE_FL_FREED flag is set. If it is, then the 1693 * data pointed to by the trace_event_file can not be trusted. 1694 * 1695 * Use the event_file_file() to access the trace_event_file from 1696 * the filp the first time under the event_mutex and check for 1697 * NULL. If it is needed to be retrieved again and the event_mutex 1698 * is still held, then the event_file_data() can be used and it 1699 * is guaranteed to be valid. 1700 */ 1701 static inline struct trace_event_file *event_file_file(struct file *filp) 1702 { 1703 struct trace_event_file *file; 1704 1705 lockdep_assert_held(&event_mutex); 1706 file = READ_ONCE(file_inode(filp)->i_private); 1707 if (!file || file->flags & EVENT_FILE_FL_FREED) 1708 return NULL; 1709 return file; 1710 } 1711 1712 extern const struct file_operations event_trigger_fops; 1713 extern const struct file_operations event_hist_fops; 1714 extern const struct file_operations event_hist_debug_fops; 1715 extern const struct file_operations event_inject_fops; 1716 1717 #ifdef CONFIG_HIST_TRIGGERS 1718 extern int register_trigger_hist_cmd(void); 1719 extern int register_trigger_hist_enable_disable_cmds(void); 1720 #else 1721 static inline int register_trigger_hist_cmd(void) { return 0; } 1722 static inline int register_trigger_hist_enable_disable_cmds(void) { return 0; } 1723 #endif 1724 1725 extern int register_trigger_cmds(void); 1726 extern void clear_event_triggers(struct trace_array *tr); 1727 1728 enum { 1729 EVENT_TRIGGER_FL_PROBE = BIT(0), 1730 }; 1731 1732 struct event_trigger_data { 1733 unsigned long count; 1734 int ref; 1735 int flags; 1736 const struct event_trigger_ops *ops; 1737 struct event_command *cmd_ops; 1738 struct event_filter __rcu *filter; 1739 char *filter_str; 1740 void *private_data; 1741 bool paused; 1742 bool paused_tmp; 1743 struct list_head list; 1744 char *name; 1745 struct list_head named_list; 1746 struct event_trigger_data *named_data; 1747 }; 1748 1749 /* Avoid typos */ 1750 #define ENABLE_EVENT_STR "enable_event" 1751 #define DISABLE_EVENT_STR "disable_event" 1752 #define ENABLE_HIST_STR "enable_hist" 1753 #define DISABLE_HIST_STR "disable_hist" 1754 1755 struct enable_trigger_data { 1756 struct trace_event_file *file; 1757 bool enable; 1758 bool hist; 1759 }; 1760 1761 extern int event_enable_trigger_print(struct seq_file *m, 1762 struct event_trigger_data *data); 1763 extern void event_enable_trigger_free(struct event_trigger_data *data); 1764 extern int event_enable_trigger_parse(struct event_command *cmd_ops, 1765 struct trace_event_file *file, 1766 char *glob, char *cmd, 1767 char *param_and_filter); 1768 extern int event_enable_register_trigger(char *glob, 1769 struct event_trigger_data *data, 1770 struct trace_event_file *file); 1771 extern void event_enable_unregister_trigger(char *glob, 1772 struct event_trigger_data *test, 1773 struct trace_event_file *file); 1774 extern void trigger_data_free(struct event_trigger_data *data); 1775 extern int event_trigger_init(struct event_trigger_data *data); 1776 extern int trace_event_trigger_enable_disable(struct trace_event_file *file, 1777 int trigger_enable); 1778 extern void update_cond_flag(struct trace_event_file *file); 1779 extern int set_trigger_filter(char *filter_str, 1780 struct event_trigger_data *trigger_data, 1781 struct trace_event_file *file); 1782 extern struct event_trigger_data *find_named_trigger(const char *name); 1783 extern bool is_named_trigger(struct event_trigger_data *test); 1784 extern int save_named_trigger(const char *name, 1785 struct event_trigger_data *data); 1786 extern void del_named_trigger(struct event_trigger_data *data); 1787 extern void pause_named_trigger(struct event_trigger_data *data); 1788 extern void unpause_named_trigger(struct event_trigger_data *data); 1789 extern void set_named_trigger_data(struct event_trigger_data *data, 1790 struct event_trigger_data *named_data); 1791 extern struct event_trigger_data * 1792 get_named_trigger_data(struct event_trigger_data *data); 1793 extern int register_event_command(struct event_command *cmd); 1794 extern int unregister_event_command(struct event_command *cmd); 1795 extern int register_trigger_hist_enable_disable_cmds(void); 1796 extern bool event_trigger_check_remove(const char *glob); 1797 extern bool event_trigger_empty_param(const char *param); 1798 extern int event_trigger_separate_filter(char *param_and_filter, char **param, 1799 char **filter, bool param_required); 1800 extern struct event_trigger_data * 1801 event_trigger_alloc(struct event_command *cmd_ops, 1802 char *cmd, 1803 char *param, 1804 void *private_data); 1805 extern int event_trigger_parse_num(char *trigger, 1806 struct event_trigger_data *trigger_data); 1807 extern int event_trigger_set_filter(struct event_command *cmd_ops, 1808 struct trace_event_file *file, 1809 char *param, 1810 struct event_trigger_data *trigger_data); 1811 extern void event_trigger_reset_filter(struct event_command *cmd_ops, 1812 struct event_trigger_data *trigger_data); 1813 extern int event_trigger_register(struct event_command *cmd_ops, 1814 struct trace_event_file *file, 1815 char *glob, 1816 struct event_trigger_data *trigger_data); 1817 extern void event_trigger_unregister(struct event_command *cmd_ops, 1818 struct trace_event_file *file, 1819 char *glob, 1820 struct event_trigger_data *trigger_data); 1821 1822 extern void event_file_get(struct trace_event_file *file); 1823 extern void event_file_put(struct trace_event_file *file); 1824 1825 /** 1826 * struct event_trigger_ops - callbacks for trace event triggers 1827 * 1828 * The methods in this structure provide per-event trigger hooks for 1829 * various trigger operations. 1830 * 1831 * The @init and @free methods are used during trigger setup and 1832 * teardown, typically called from an event_command's @parse() 1833 * function implementation. 1834 * 1835 * The @print method is used to print the trigger spec. 1836 * 1837 * The @trigger method is the function that actually implements the 1838 * trigger and is called in the context of the triggering event 1839 * whenever that event occurs. 1840 * 1841 * All the methods below, except for @init() and @free(), must be 1842 * implemented. 1843 * 1844 * @trigger: The trigger 'probe' function called when the triggering 1845 * event occurs. The data passed into this callback is the data 1846 * that was supplied to the event_command @reg() function that 1847 * registered the trigger (see struct event_command) along with 1848 * the trace record, rec. 1849 * 1850 * @init: An optional initialization function called for the trigger 1851 * when the trigger is registered (via the event_command reg() 1852 * function). This can be used to perform per-trigger 1853 * initialization such as incrementing a per-trigger reference 1854 * count, for instance. This is usually implemented by the 1855 * generic utility function @event_trigger_init() (see 1856 * trace_event_triggers.c). 1857 * 1858 * @free: An optional de-initialization function called for the 1859 * trigger when the trigger is unregistered (via the 1860 * event_command @reg() function). This can be used to perform 1861 * per-trigger de-initialization such as decrementing a 1862 * per-trigger reference count and freeing corresponding trigger 1863 * data, for instance. This is usually implemented by the 1864 * generic utility function @event_trigger_free() (see 1865 * trace_event_triggers.c). 1866 * 1867 * @print: The callback function invoked to have the trigger print 1868 * itself. This is usually implemented by a wrapper function 1869 * that calls the generic utility function @event_trigger_print() 1870 * (see trace_event_triggers.c). 1871 */ 1872 struct event_trigger_ops { 1873 void (*trigger)(struct event_trigger_data *data, 1874 struct trace_buffer *buffer, 1875 void *rec, 1876 struct ring_buffer_event *rbe); 1877 int (*init)(struct event_trigger_data *data); 1878 void (*free)(struct event_trigger_data *data); 1879 int (*print)(struct seq_file *m, 1880 struct event_trigger_data *data); 1881 }; 1882 1883 /** 1884 * struct event_command - callbacks and data members for event commands 1885 * 1886 * Event commands are invoked by users by writing the command name 1887 * into the 'trigger' file associated with a trace event. The 1888 * parameters associated with a specific invocation of an event 1889 * command are used to create an event trigger instance, which is 1890 * added to the list of trigger instances associated with that trace 1891 * event. When the event is hit, the set of triggers associated with 1892 * that event is invoked. 1893 * 1894 * The data members in this structure provide per-event command data 1895 * for various event commands. 1896 * 1897 * All the data members below, except for @post_trigger, must be set 1898 * for each event command. 1899 * 1900 * @name: The unique name that identifies the event command. This is 1901 * the name used when setting triggers via trigger files. 1902 * 1903 * @trigger_type: A unique id that identifies the event command 1904 * 'type'. This value has two purposes, the first to ensure that 1905 * only one trigger of the same type can be set at a given time 1906 * for a particular event e.g. it doesn't make sense to have both 1907 * a traceon and traceoff trigger attached to a single event at 1908 * the same time, so traceon and traceoff have the same type 1909 * though they have different names. The @trigger_type value is 1910 * also used as a bit value for deferring the actual trigger 1911 * action until after the current event is finished. Some 1912 * commands need to do this if they themselves log to the trace 1913 * buffer (see the @post_trigger() member below). @trigger_type 1914 * values are defined by adding new values to the trigger_type 1915 * enum in include/linux/trace_events.h. 1916 * 1917 * @flags: See the enum event_command_flags below. 1918 * 1919 * All the methods below, except for @set_filter() and @unreg_all(), 1920 * must be implemented. 1921 * 1922 * @parse: The callback function responsible for parsing and 1923 * registering the trigger written to the 'trigger' file by the 1924 * user. It allocates the trigger instance and registers it with 1925 * the appropriate trace event. It makes use of the other 1926 * event_command callback functions to orchestrate this, and is 1927 * usually implemented by the generic utility function 1928 * @event_trigger_callback() (see trace_event_triggers.c). 1929 * 1930 * @reg: Adds the trigger to the list of triggers associated with the 1931 * event, and enables the event trigger itself, after 1932 * initializing it (via the event_trigger_ops @init() function). 1933 * This is also where commands can use the @trigger_type value to 1934 * make the decision as to whether or not multiple instances of 1935 * the trigger should be allowed. This is usually implemented by 1936 * the generic utility function @register_trigger() (see 1937 * trace_event_triggers.c). 1938 * 1939 * @unreg: Removes the trigger from the list of triggers associated 1940 * with the event, and disables the event trigger itself, after 1941 * initializing it (via the event_trigger_ops @free() function). 1942 * This is usually implemented by the generic utility function 1943 * @unregister_trigger() (see trace_event_triggers.c). 1944 * 1945 * @unreg_all: An optional function called to remove all the triggers 1946 * from the list of triggers associated with the event. Called 1947 * when a trigger file is opened in truncate mode. 1948 * 1949 * @set_filter: An optional function called to parse and set a filter 1950 * for the trigger. If no @set_filter() method is set for the 1951 * event command, filters set by the user for the command will be 1952 * ignored. This is usually implemented by the generic utility 1953 * function @set_trigger_filter() (see trace_event_triggers.c). 1954 * 1955 * @get_trigger_ops: The callback function invoked to retrieve the 1956 * event_trigger_ops implementation associated with the command. 1957 * This callback function allows a single event_command to 1958 * support multiple trigger implementations via different sets of 1959 * event_trigger_ops, depending on the value of the @param 1960 * string. 1961 */ 1962 struct event_command { 1963 struct list_head list; 1964 char *name; 1965 enum event_trigger_type trigger_type; 1966 int flags; 1967 int (*parse)(struct event_command *cmd_ops, 1968 struct trace_event_file *file, 1969 char *glob, char *cmd, 1970 char *param_and_filter); 1971 int (*reg)(char *glob, 1972 struct event_trigger_data *data, 1973 struct trace_event_file *file); 1974 void (*unreg)(char *glob, 1975 struct event_trigger_data *data, 1976 struct trace_event_file *file); 1977 void (*unreg_all)(struct trace_event_file *file); 1978 int (*set_filter)(char *filter_str, 1979 struct event_trigger_data *data, 1980 struct trace_event_file *file); 1981 const struct event_trigger_ops *(*get_trigger_ops)(char *cmd, char *param); 1982 }; 1983 1984 /** 1985 * enum event_command_flags - flags for struct event_command 1986 * 1987 * @POST_TRIGGER: A flag that says whether or not this command needs 1988 * to have its action delayed until after the current event has 1989 * been closed. Some triggers need to avoid being invoked while 1990 * an event is currently in the process of being logged, since 1991 * the trigger may itself log data into the trace buffer. Thus 1992 * we make sure the current event is committed before invoking 1993 * those triggers. To do that, the trigger invocation is split 1994 * in two - the first part checks the filter using the current 1995 * trace record; if a command has the @post_trigger flag set, it 1996 * sets a bit for itself in the return value, otherwise it 1997 * directly invokes the trigger. Once all commands have been 1998 * either invoked or set their return flag, the current record is 1999 * either committed or discarded. At that point, if any commands 2000 * have deferred their triggers, those commands are finally 2001 * invoked following the close of the current event. In other 2002 * words, if the event_trigger_ops @func() probe implementation 2003 * itself logs to the trace buffer, this flag should be set, 2004 * otherwise it can be left unspecified. 2005 * 2006 * @NEEDS_REC: A flag that says whether or not this command needs 2007 * access to the trace record in order to perform its function, 2008 * regardless of whether or not it has a filter associated with 2009 * it (filters make a trigger require access to the trace record 2010 * but are not always present). 2011 */ 2012 enum event_command_flags { 2013 EVENT_CMD_FL_POST_TRIGGER = 1, 2014 EVENT_CMD_FL_NEEDS_REC = 2, 2015 }; 2016 2017 static inline bool event_command_post_trigger(struct event_command *cmd_ops) 2018 { 2019 return cmd_ops->flags & EVENT_CMD_FL_POST_TRIGGER; 2020 } 2021 2022 static inline bool event_command_needs_rec(struct event_command *cmd_ops) 2023 { 2024 return cmd_ops->flags & EVENT_CMD_FL_NEEDS_REC; 2025 } 2026 2027 extern int trace_event_enable_disable(struct trace_event_file *file, 2028 int enable, int soft_disable); 2029 extern int tracing_alloc_snapshot(void); 2030 extern void tracing_snapshot_cond(struct trace_array *tr, void *cond_data); 2031 extern int tracing_snapshot_cond_enable(struct trace_array *tr, void *cond_data, cond_update_fn_t update); 2032 2033 extern int tracing_snapshot_cond_disable(struct trace_array *tr); 2034 extern void *tracing_cond_snapshot_data(struct trace_array *tr); 2035 2036 extern const char *__start___trace_bprintk_fmt[]; 2037 extern const char *__stop___trace_bprintk_fmt[]; 2038 2039 extern const char *__start___tracepoint_str[]; 2040 extern const char *__stop___tracepoint_str[]; 2041 2042 void trace_printk_control(bool enabled); 2043 void trace_printk_start_comm(void); 2044 int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set); 2045 int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled); 2046 2047 /* Used from boot time tracer */ 2048 extern int trace_set_options(struct trace_array *tr, char *option); 2049 extern int tracing_set_tracer(struct trace_array *tr, const char *buf); 2050 extern ssize_t tracing_resize_ring_buffer(struct trace_array *tr, 2051 unsigned long size, int cpu_id); 2052 extern int tracing_set_cpumask(struct trace_array *tr, 2053 cpumask_var_t tracing_cpumask_new); 2054 2055 2056 #define MAX_EVENT_NAME_LEN 64 2057 2058 extern ssize_t trace_parse_run_command(struct file *file, 2059 const char __user *buffer, size_t count, loff_t *ppos, 2060 int (*createfn)(const char *)); 2061 2062 extern unsigned int err_pos(char *cmd, const char *str); 2063 extern void tracing_log_err(struct trace_array *tr, 2064 const char *loc, const char *cmd, 2065 const char **errs, u8 type, u16 pos); 2066 2067 /* 2068 * Normal trace_printk() and friends allocates special buffers 2069 * to do the manipulation, as well as saves the print formats 2070 * into sections to display. But the trace infrastructure wants 2071 * to use these without the added overhead at the price of being 2072 * a bit slower (used mainly for warnings, where we don't care 2073 * about performance). The internal_trace_puts() is for such 2074 * a purpose. 2075 */ 2076 #define internal_trace_puts(str) __trace_puts(_THIS_IP_, str, strlen(str)) 2077 2078 #undef FTRACE_ENTRY 2079 #define FTRACE_ENTRY(call, struct_name, id, tstruct, print) \ 2080 extern struct trace_event_call \ 2081 __aligned(4) event_##call; 2082 #undef FTRACE_ENTRY_DUP 2083 #define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print) \ 2084 FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print)) 2085 #undef FTRACE_ENTRY_PACKED 2086 #define FTRACE_ENTRY_PACKED(call, struct_name, id, tstruct, print) \ 2087 FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print)) 2088 2089 #include "trace_entries.h" 2090 2091 #if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER) 2092 int perf_ftrace_event_register(struct trace_event_call *call, 2093 enum trace_reg type, void *data); 2094 #else 2095 #define perf_ftrace_event_register NULL 2096 #endif 2097 2098 #ifdef CONFIG_FTRACE_SYSCALLS 2099 void init_ftrace_syscalls(void); 2100 const char *get_syscall_name(int syscall); 2101 #else 2102 static inline void init_ftrace_syscalls(void) { } 2103 static inline const char *get_syscall_name(int syscall) 2104 { 2105 return NULL; 2106 } 2107 #endif 2108 2109 #ifdef CONFIG_EVENT_TRACING 2110 void trace_event_init(void); 2111 void trace_event_eval_update(struct trace_eval_map **map, int len); 2112 /* Used from boot time tracer */ 2113 extern int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set); 2114 extern int trigger_process_regex(struct trace_event_file *file, char *buff); 2115 #else 2116 static inline void __init trace_event_init(void) { } 2117 static inline void trace_event_eval_update(struct trace_eval_map **map, int len) { } 2118 #endif 2119 2120 #ifdef CONFIG_TRACER_SNAPSHOT 2121 void tracing_snapshot_instance(struct trace_array *tr); 2122 int tracing_alloc_snapshot_instance(struct trace_array *tr); 2123 int tracing_arm_snapshot(struct trace_array *tr); 2124 void tracing_disarm_snapshot(struct trace_array *tr); 2125 #else 2126 static inline void tracing_snapshot_instance(struct trace_array *tr) { } 2127 static inline int tracing_alloc_snapshot_instance(struct trace_array *tr) 2128 { 2129 return 0; 2130 } 2131 static inline int tracing_arm_snapshot(struct trace_array *tr) { return 0; } 2132 static inline void tracing_disarm_snapshot(struct trace_array *tr) { } 2133 #endif 2134 2135 #ifdef CONFIG_PREEMPT_TRACER 2136 void tracer_preempt_on(unsigned long a0, unsigned long a1); 2137 void tracer_preempt_off(unsigned long a0, unsigned long a1); 2138 #else 2139 static inline void tracer_preempt_on(unsigned long a0, unsigned long a1) { } 2140 static inline void tracer_preempt_off(unsigned long a0, unsigned long a1) { } 2141 #endif 2142 #ifdef CONFIG_IRQSOFF_TRACER 2143 void tracer_hardirqs_on(unsigned long a0, unsigned long a1); 2144 void tracer_hardirqs_off(unsigned long a0, unsigned long a1); 2145 #else 2146 static inline void tracer_hardirqs_on(unsigned long a0, unsigned long a1) { } 2147 static inline void tracer_hardirqs_off(unsigned long a0, unsigned long a1) { } 2148 #endif 2149 2150 /* 2151 * Reset the state of the trace_iterator so that it can read consumed data. 2152 * Normally, the trace_iterator is used for reading the data when it is not 2153 * consumed, and must retain state. 2154 */ 2155 static __always_inline void trace_iterator_reset(struct trace_iterator *iter) 2156 { 2157 memset_startat(iter, 0, seq); 2158 iter->pos = -1; 2159 } 2160 2161 /* Check the name is good for event/group/fields */ 2162 static inline bool __is_good_name(const char *name, bool hash_ok) 2163 { 2164 if (!isalpha(*name) && *name != '_' && (!hash_ok || *name != '-')) 2165 return false; 2166 while (*++name != '\0') { 2167 if (!isalpha(*name) && !isdigit(*name) && *name != '_' && 2168 (!hash_ok || *name != '-')) 2169 return false; 2170 } 2171 return true; 2172 } 2173 2174 /* Check the name is good for event/group/fields */ 2175 static inline bool is_good_name(const char *name) 2176 { 2177 return __is_good_name(name, false); 2178 } 2179 2180 /* Check the name is good for system */ 2181 static inline bool is_good_system_name(const char *name) 2182 { 2183 return __is_good_name(name, true); 2184 } 2185 2186 /* Convert certain expected symbols into '_' when generating event names */ 2187 static inline void sanitize_event_name(char *name) 2188 { 2189 while (*name++ != '\0') 2190 if (*name == ':' || *name == '.') 2191 *name = '_'; 2192 } 2193 2194 /* 2195 * This is a generic way to read and write a u64 value from a file in tracefs. 2196 * 2197 * The value is stored on the variable pointed by *val. The value needs 2198 * to be at least *min and at most *max. The write is protected by an 2199 * existing *lock. 2200 */ 2201 struct trace_min_max_param { 2202 struct mutex *lock; 2203 u64 *val; 2204 u64 *min; 2205 u64 *max; 2206 }; 2207 2208 #define U64_STR_SIZE 24 /* 20 digits max */ 2209 2210 extern const struct file_operations trace_min_max_fops; 2211 2212 #ifdef CONFIG_RV 2213 extern int rv_init_interface(void); 2214 #else 2215 static inline int rv_init_interface(void) 2216 { 2217 return 0; 2218 } 2219 #endif 2220 2221 /* 2222 * This is used only to distinguish 2223 * function address from trampoline code. 2224 * So this value has no meaning. 2225 */ 2226 #define FTRACE_TRAMPOLINE_MARKER ((unsigned long) INT_MAX) 2227 2228 #endif /* _LINUX_KERNEL_TRACE_H */ 2229