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