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 23 #ifdef CONFIG_FTRACE_SYSCALLS 24 #include <asm/unistd.h> /* For NR_SYSCALLS */ 25 #include <asm/syscall.h> /* some archs define it here */ 26 #endif 27 28 enum trace_type { 29 __TRACE_FIRST_TYPE = 0, 30 31 TRACE_FN, 32 TRACE_CTX, 33 TRACE_WAKE, 34 TRACE_STACK, 35 TRACE_PRINT, 36 TRACE_BPRINT, 37 TRACE_MMIO_RW, 38 TRACE_MMIO_MAP, 39 TRACE_BRANCH, 40 TRACE_GRAPH_RET, 41 TRACE_GRAPH_ENT, 42 TRACE_USER_STACK, 43 TRACE_BLK, 44 TRACE_BPUTS, 45 TRACE_HWLAT, 46 TRACE_RAW_DATA, 47 48 __TRACE_LAST_TYPE, 49 }; 50 51 52 #undef __field 53 #define __field(type, item) type item; 54 55 #undef __field_fn 56 #define __field_fn(type, item) type item; 57 58 #undef __field_struct 59 #define __field_struct(type, item) __field(type, item) 60 61 #undef __field_desc 62 #define __field_desc(type, container, item) 63 64 #undef __field_packed 65 #define __field_packed(type, container, item) 66 67 #undef __array 68 #define __array(type, item, size) type item[size]; 69 70 #undef __array_desc 71 #define __array_desc(type, container, item, size) 72 73 #undef __dynamic_array 74 #define __dynamic_array(type, item) type item[]; 75 76 #undef F_STRUCT 77 #define F_STRUCT(args...) args 78 79 #undef FTRACE_ENTRY 80 #define FTRACE_ENTRY(name, struct_name, id, tstruct, print) \ 81 struct struct_name { \ 82 struct trace_entry ent; \ 83 tstruct \ 84 } 85 86 #undef FTRACE_ENTRY_DUP 87 #define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk) 88 89 #undef FTRACE_ENTRY_REG 90 #define FTRACE_ENTRY_REG(name, struct_name, id, tstruct, print, regfn) \ 91 FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print)) 92 93 #undef FTRACE_ENTRY_PACKED 94 #define FTRACE_ENTRY_PACKED(name, struct_name, id, tstruct, print) \ 95 FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print)) __packed 96 97 #include "trace_entries.h" 98 99 /* Use this for memory failure errors */ 100 #define MEM_FAIL(condition, fmt, ...) ({ \ 101 static bool __section(.data.once) __warned; \ 102 int __ret_warn_once = !!(condition); \ 103 \ 104 if (unlikely(__ret_warn_once && !__warned)) { \ 105 __warned = true; \ 106 pr_err("ERROR: " fmt, ##__VA_ARGS__); \ 107 } \ 108 unlikely(__ret_warn_once); \ 109 }) 110 111 /* 112 * syscalls are special, and need special handling, this is why 113 * they are not included in trace_entries.h 114 */ 115 struct syscall_trace_enter { 116 struct trace_entry ent; 117 int nr; 118 unsigned long args[]; 119 }; 120 121 struct syscall_trace_exit { 122 struct trace_entry ent; 123 int nr; 124 long ret; 125 }; 126 127 struct kprobe_trace_entry_head { 128 struct trace_entry ent; 129 unsigned long ip; 130 }; 131 132 struct kretprobe_trace_entry_head { 133 struct trace_entry ent; 134 unsigned long func; 135 unsigned long ret_ip; 136 }; 137 138 /* 139 * trace_flag_type is an enumeration that holds different 140 * states when a trace occurs. These are: 141 * IRQS_OFF - interrupts were disabled 142 * IRQS_NOSUPPORT - arch does not support irqs_disabled_flags 143 * NEED_RESCHED - reschedule is requested 144 * HARDIRQ - inside an interrupt handler 145 * SOFTIRQ - inside a softirq handler 146 */ 147 enum trace_flag_type { 148 TRACE_FLAG_IRQS_OFF = 0x01, 149 TRACE_FLAG_IRQS_NOSUPPORT = 0x02, 150 TRACE_FLAG_NEED_RESCHED = 0x04, 151 TRACE_FLAG_HARDIRQ = 0x08, 152 TRACE_FLAG_SOFTIRQ = 0x10, 153 TRACE_FLAG_PREEMPT_RESCHED = 0x20, 154 TRACE_FLAG_NMI = 0x40, 155 }; 156 157 #define TRACE_BUF_SIZE 1024 158 159 struct trace_array; 160 161 /* 162 * The CPU trace array - it consists of thousands of trace entries 163 * plus some other descriptor data: (for example which task started 164 * the trace, etc.) 165 */ 166 struct trace_array_cpu { 167 atomic_t disabled; 168 void *buffer_page; /* ring buffer spare */ 169 170 unsigned long entries; 171 unsigned long saved_latency; 172 unsigned long critical_start; 173 unsigned long critical_end; 174 unsigned long critical_sequence; 175 unsigned long nice; 176 unsigned long policy; 177 unsigned long rt_priority; 178 unsigned long skipped_entries; 179 u64 preempt_timestamp; 180 pid_t pid; 181 kuid_t uid; 182 char comm[TASK_COMM_LEN]; 183 184 #ifdef CONFIG_FUNCTION_TRACER 185 int ftrace_ignore_pid; 186 #endif 187 bool ignore_pid; 188 }; 189 190 struct tracer; 191 struct trace_option_dentry; 192 193 struct array_buffer { 194 struct trace_array *tr; 195 struct trace_buffer *buffer; 196 struct trace_array_cpu __percpu *data; 197 u64 time_start; 198 int cpu; 199 }; 200 201 #define TRACE_FLAGS_MAX_SIZE 32 202 203 struct trace_options { 204 struct tracer *tracer; 205 struct trace_option_dentry *topts; 206 }; 207 208 struct trace_pid_list { 209 int pid_max; 210 unsigned long *pids; 211 }; 212 213 enum { 214 TRACE_PIDS = BIT(0), 215 TRACE_NO_PIDS = BIT(1), 216 }; 217 218 static inline bool pid_type_enabled(int type, struct trace_pid_list *pid_list, 219 struct trace_pid_list *no_pid_list) 220 { 221 /* Return true if the pid list in type has pids */ 222 return ((type & TRACE_PIDS) && pid_list) || 223 ((type & TRACE_NO_PIDS) && no_pid_list); 224 } 225 226 static inline bool still_need_pid_events(int type, struct trace_pid_list *pid_list, 227 struct trace_pid_list *no_pid_list) 228 { 229 /* 230 * Turning off what is in @type, return true if the "other" 231 * pid list, still has pids in it. 232 */ 233 return (!(type & TRACE_PIDS) && pid_list) || 234 (!(type & TRACE_NO_PIDS) && no_pid_list); 235 } 236 237 typedef bool (*cond_update_fn_t)(struct trace_array *tr, void *cond_data); 238 239 /** 240 * struct cond_snapshot - conditional snapshot data and callback 241 * 242 * The cond_snapshot structure encapsulates a callback function and 243 * data associated with the snapshot for a given tracing instance. 244 * 245 * When a snapshot is taken conditionally, by invoking 246 * tracing_snapshot_cond(tr, cond_data), the cond_data passed in is 247 * passed in turn to the cond_snapshot.update() function. That data 248 * can be compared by the update() implementation with the cond_data 249 * contained wihin the struct cond_snapshot instance associated with 250 * the trace_array. Because the tr->max_lock is held throughout the 251 * update() call, the update() function can directly retrieve the 252 * cond_snapshot and cond_data associated with the per-instance 253 * snapshot associated with the trace_array. 254 * 255 * The cond_snapshot.update() implementation can save data to be 256 * associated with the snapshot if it decides to, and returns 'true' 257 * in that case, or it returns 'false' if the conditional snapshot 258 * shouldn't be taken. 259 * 260 * The cond_snapshot instance is created and associated with the 261 * user-defined cond_data by tracing_cond_snapshot_enable(). 262 * Likewise, the cond_snapshot instance is destroyed and is no longer 263 * associated with the trace instance by 264 * tracing_cond_snapshot_disable(). 265 * 266 * The method below is required. 267 * 268 * @update: When a conditional snapshot is invoked, the update() 269 * callback function is invoked with the tr->max_lock held. The 270 * update() implementation signals whether or not to actually 271 * take the snapshot, by returning 'true' if so, 'false' if no 272 * snapshot should be taken. Because the max_lock is held for 273 * the duration of update(), the implementation is safe to 274 * directly retrieven and save any implementation data it needs 275 * to in association with the snapshot. 276 */ 277 struct cond_snapshot { 278 void *cond_data; 279 cond_update_fn_t update; 280 }; 281 282 /* 283 * The trace array - an array of per-CPU trace arrays. This is the 284 * highest level data structure that individual tracers deal with. 285 * They have on/off state as well: 286 */ 287 struct trace_array { 288 struct list_head list; 289 char *name; 290 struct array_buffer array_buffer; 291 #ifdef CONFIG_TRACER_MAX_TRACE 292 /* 293 * The max_buffer is used to snapshot the trace when a maximum 294 * latency is reached, or when the user initiates a snapshot. 295 * Some tracers will use this to store a maximum trace while 296 * it continues examining live traces. 297 * 298 * The buffers for the max_buffer are set up the same as the array_buffer 299 * When a snapshot is taken, the buffer of the max_buffer is swapped 300 * with the buffer of the array_buffer and the buffers are reset for 301 * the array_buffer so the tracing can continue. 302 */ 303 struct array_buffer max_buffer; 304 bool allocated_snapshot; 305 #endif 306 #if defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER) 307 unsigned long max_latency; 308 #ifdef CONFIG_FSNOTIFY 309 struct dentry *d_max_latency; 310 struct work_struct fsnotify_work; 311 struct irq_work fsnotify_irqwork; 312 #endif 313 #endif 314 struct trace_pid_list __rcu *filtered_pids; 315 struct trace_pid_list __rcu *filtered_no_pids; 316 /* 317 * max_lock is used to protect the swapping of buffers 318 * when taking a max snapshot. The buffers themselves are 319 * protected by per_cpu spinlocks. But the action of the swap 320 * needs its own lock. 321 * 322 * This is defined as a arch_spinlock_t in order to help 323 * with performance when lockdep debugging is enabled. 324 * 325 * It is also used in other places outside the update_max_tr 326 * so it needs to be defined outside of the 327 * CONFIG_TRACER_MAX_TRACE. 328 */ 329 arch_spinlock_t max_lock; 330 int buffer_disabled; 331 #ifdef CONFIG_FTRACE_SYSCALLS 332 int sys_refcount_enter; 333 int sys_refcount_exit; 334 struct trace_event_file __rcu *enter_syscall_files[NR_syscalls]; 335 struct trace_event_file __rcu *exit_syscall_files[NR_syscalls]; 336 #endif 337 int stop_count; 338 int clock_id; 339 int nr_topts; 340 bool clear_trace; 341 int buffer_percent; 342 unsigned int n_err_log_entries; 343 struct tracer *current_trace; 344 unsigned int trace_flags; 345 unsigned char trace_flags_index[TRACE_FLAGS_MAX_SIZE]; 346 unsigned int flags; 347 raw_spinlock_t start_lock; 348 struct list_head err_log; 349 struct dentry *dir; 350 struct dentry *options; 351 struct dentry *percpu_dir; 352 struct dentry *event_dir; 353 struct trace_options *topts; 354 struct list_head systems; 355 struct list_head events; 356 struct trace_event_file *trace_marker_file; 357 cpumask_var_t tracing_cpumask; /* only trace on set CPUs */ 358 int ref; 359 int trace_ref; 360 #ifdef CONFIG_FUNCTION_TRACER 361 struct ftrace_ops *ops; 362 struct trace_pid_list __rcu *function_pids; 363 struct trace_pid_list __rcu *function_no_pids; 364 #ifdef CONFIG_DYNAMIC_FTRACE 365 /* All of these are protected by the ftrace_lock */ 366 struct list_head func_probes; 367 struct list_head mod_trace; 368 struct list_head mod_notrace; 369 #endif 370 /* function tracing enabled */ 371 int function_enabled; 372 #endif 373 int time_stamp_abs_ref; 374 struct list_head hist_vars; 375 #ifdef CONFIG_TRACER_SNAPSHOT 376 struct cond_snapshot *cond_snapshot; 377 #endif 378 }; 379 380 enum { 381 TRACE_ARRAY_FL_GLOBAL = (1 << 0) 382 }; 383 384 extern struct list_head ftrace_trace_arrays; 385 386 extern struct mutex trace_types_lock; 387 388 extern int trace_array_get(struct trace_array *tr); 389 extern int tracing_check_open_get_tr(struct trace_array *tr); 390 extern struct trace_array *trace_array_find(const char *instance); 391 extern struct trace_array *trace_array_find_get(const char *instance); 392 393 extern int tracing_set_time_stamp_abs(struct trace_array *tr, bool abs); 394 extern int tracing_set_clock(struct trace_array *tr, const char *clockstr); 395 396 extern bool trace_clock_in_ns(struct trace_array *tr); 397 398 /* 399 * The global tracer (top) should be the first trace array added, 400 * but we check the flag anyway. 401 */ 402 static inline struct trace_array *top_trace_array(void) 403 { 404 struct trace_array *tr; 405 406 if (list_empty(&ftrace_trace_arrays)) 407 return NULL; 408 409 tr = list_entry(ftrace_trace_arrays.prev, 410 typeof(*tr), list); 411 WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL)); 412 return tr; 413 } 414 415 #define FTRACE_CMP_TYPE(var, type) \ 416 __builtin_types_compatible_p(typeof(var), type *) 417 418 #undef IF_ASSIGN 419 #define IF_ASSIGN(var, entry, etype, id) \ 420 if (FTRACE_CMP_TYPE(var, etype)) { \ 421 var = (typeof(var))(entry); \ 422 WARN_ON(id != 0 && (entry)->type != id); \ 423 break; \ 424 } 425 426 /* Will cause compile errors if type is not found. */ 427 extern void __ftrace_bad_type(void); 428 429 /* 430 * The trace_assign_type is a verifier that the entry type is 431 * the same as the type being assigned. To add new types simply 432 * add a line with the following format: 433 * 434 * IF_ASSIGN(var, ent, type, id); 435 * 436 * Where "type" is the trace type that includes the trace_entry 437 * as the "ent" item. And "id" is the trace identifier that is 438 * used in the trace_type enum. 439 * 440 * If the type can have more than one id, then use zero. 441 */ 442 #define trace_assign_type(var, ent) \ 443 do { \ 444 IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN); \ 445 IF_ASSIGN(var, ent, struct ctx_switch_entry, 0); \ 446 IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK); \ 447 IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\ 448 IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT); \ 449 IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT); \ 450 IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS); \ 451 IF_ASSIGN(var, ent, struct hwlat_entry, TRACE_HWLAT); \ 452 IF_ASSIGN(var, ent, struct raw_data_entry, TRACE_RAW_DATA);\ 453 IF_ASSIGN(var, ent, struct trace_mmiotrace_rw, \ 454 TRACE_MMIO_RW); \ 455 IF_ASSIGN(var, ent, struct trace_mmiotrace_map, \ 456 TRACE_MMIO_MAP); \ 457 IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \ 458 IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry, \ 459 TRACE_GRAPH_ENT); \ 460 IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry, \ 461 TRACE_GRAPH_RET); \ 462 __ftrace_bad_type(); \ 463 } while (0) 464 465 /* 466 * An option specific to a tracer. This is a boolean value. 467 * The bit is the bit index that sets its value on the 468 * flags value in struct tracer_flags. 469 */ 470 struct tracer_opt { 471 const char *name; /* Will appear on the trace_options file */ 472 u32 bit; /* Mask assigned in val field in tracer_flags */ 473 }; 474 475 /* 476 * The set of specific options for a tracer. Your tracer 477 * have to set the initial value of the flags val. 478 */ 479 struct tracer_flags { 480 u32 val; 481 struct tracer_opt *opts; 482 struct tracer *trace; 483 }; 484 485 /* Makes more easy to define a tracer opt */ 486 #define TRACER_OPT(s, b) .name = #s, .bit = b 487 488 489 struct trace_option_dentry { 490 struct tracer_opt *opt; 491 struct tracer_flags *flags; 492 struct trace_array *tr; 493 struct dentry *entry; 494 }; 495 496 /** 497 * struct tracer - a specific tracer and its callbacks to interact with tracefs 498 * @name: the name chosen to select it on the available_tracers file 499 * @init: called when one switches to this tracer (echo name > current_tracer) 500 * @reset: called when one switches to another tracer 501 * @start: called when tracing is unpaused (echo 1 > tracing_on) 502 * @stop: called when tracing is paused (echo 0 > tracing_on) 503 * @update_thresh: called when tracing_thresh is updated 504 * @open: called when the trace file is opened 505 * @pipe_open: called when the trace_pipe file is opened 506 * @close: called when the trace file is released 507 * @pipe_close: called when the trace_pipe file is released 508 * @read: override the default read callback on trace_pipe 509 * @splice_read: override the default splice_read callback on trace_pipe 510 * @selftest: selftest to run on boot (see trace_selftest.c) 511 * @print_headers: override the first lines that describe your columns 512 * @print_line: callback that prints a trace 513 * @set_flag: signals one of your private flags changed (trace_options file) 514 * @flags: your private flags 515 */ 516 struct tracer { 517 const char *name; 518 int (*init)(struct trace_array *tr); 519 void (*reset)(struct trace_array *tr); 520 void (*start)(struct trace_array *tr); 521 void (*stop)(struct trace_array *tr); 522 int (*update_thresh)(struct trace_array *tr); 523 void (*open)(struct trace_iterator *iter); 524 void (*pipe_open)(struct trace_iterator *iter); 525 void (*close)(struct trace_iterator *iter); 526 void (*pipe_close)(struct trace_iterator *iter); 527 ssize_t (*read)(struct trace_iterator *iter, 528 struct file *filp, char __user *ubuf, 529 size_t cnt, loff_t *ppos); 530 ssize_t (*splice_read)(struct trace_iterator *iter, 531 struct file *filp, 532 loff_t *ppos, 533 struct pipe_inode_info *pipe, 534 size_t len, 535 unsigned int flags); 536 #ifdef CONFIG_FTRACE_STARTUP_TEST 537 int (*selftest)(struct tracer *trace, 538 struct trace_array *tr); 539 #endif 540 void (*print_header)(struct seq_file *m); 541 enum print_line_t (*print_line)(struct trace_iterator *iter); 542 /* If you handled the flag setting, return 0 */ 543 int (*set_flag)(struct trace_array *tr, 544 u32 old_flags, u32 bit, int set); 545 /* Return 0 if OK with change, else return non-zero */ 546 int (*flag_changed)(struct trace_array *tr, 547 u32 mask, int set); 548 struct tracer *next; 549 struct tracer_flags *flags; 550 int enabled; 551 bool print_max; 552 bool allow_instances; 553 #ifdef CONFIG_TRACER_MAX_TRACE 554 bool use_max_tr; 555 #endif 556 /* True if tracer cannot be enabled in kernel param */ 557 bool noboot; 558 }; 559 560 561 /* Only current can touch trace_recursion */ 562 563 /* 564 * For function tracing recursion: 565 * The order of these bits are important. 566 * 567 * When function tracing occurs, the following steps are made: 568 * If arch does not support a ftrace feature: 569 * call internal function (uses INTERNAL bits) which calls... 570 * If callback is registered to the "global" list, the list 571 * function is called and recursion checks the GLOBAL bits. 572 * then this function calls... 573 * The function callback, which can use the FTRACE bits to 574 * check for recursion. 575 * 576 * Now if the arch does not suppport a feature, and it calls 577 * the global list function which calls the ftrace callback 578 * all three of these steps will do a recursion protection. 579 * There's no reason to do one if the previous caller already 580 * did. The recursion that we are protecting against will 581 * go through the same steps again. 582 * 583 * To prevent the multiple recursion checks, if a recursion 584 * bit is set that is higher than the MAX bit of the current 585 * check, then we know that the check was made by the previous 586 * caller, and we can skip the current check. 587 */ 588 enum { 589 /* Function recursion bits */ 590 TRACE_FTRACE_BIT, 591 TRACE_FTRACE_NMI_BIT, 592 TRACE_FTRACE_IRQ_BIT, 593 TRACE_FTRACE_SIRQ_BIT, 594 595 /* INTERNAL_BITs must be greater than FTRACE_BITs */ 596 TRACE_INTERNAL_BIT, 597 TRACE_INTERNAL_NMI_BIT, 598 TRACE_INTERNAL_IRQ_BIT, 599 TRACE_INTERNAL_SIRQ_BIT, 600 601 TRACE_BRANCH_BIT, 602 /* 603 * Abuse of the trace_recursion. 604 * As we need a way to maintain state if we are tracing the function 605 * graph in irq because we want to trace a particular function that 606 * was called in irq context but we have irq tracing off. Since this 607 * can only be modified by current, we can reuse trace_recursion. 608 */ 609 TRACE_IRQ_BIT, 610 611 /* Set if the function is in the set_graph_function file */ 612 TRACE_GRAPH_BIT, 613 614 /* 615 * In the very unlikely case that an interrupt came in 616 * at a start of graph tracing, and we want to trace 617 * the function in that interrupt, the depth can be greater 618 * than zero, because of the preempted start of a previous 619 * trace. In an even more unlikely case, depth could be 2 620 * if a softirq interrupted the start of graph tracing, 621 * followed by an interrupt preempting a start of graph 622 * tracing in the softirq, and depth can even be 3 623 * if an NMI came in at the start of an interrupt function 624 * that preempted a softirq start of a function that 625 * preempted normal context!!!! Luckily, it can't be 626 * greater than 3, so the next two bits are a mask 627 * of what the depth is when we set TRACE_GRAPH_BIT 628 */ 629 630 TRACE_GRAPH_DEPTH_START_BIT, 631 TRACE_GRAPH_DEPTH_END_BIT, 632 633 /* 634 * To implement set_graph_notrace, if this bit is set, we ignore 635 * function graph tracing of called functions, until the return 636 * function is called to clear it. 637 */ 638 TRACE_GRAPH_NOTRACE_BIT, 639 }; 640 641 #define trace_recursion_set(bit) do { (current)->trace_recursion |= (1<<(bit)); } while (0) 642 #define trace_recursion_clear(bit) do { (current)->trace_recursion &= ~(1<<(bit)); } while (0) 643 #define trace_recursion_test(bit) ((current)->trace_recursion & (1<<(bit))) 644 645 #define trace_recursion_depth() \ 646 (((current)->trace_recursion >> TRACE_GRAPH_DEPTH_START_BIT) & 3) 647 #define trace_recursion_set_depth(depth) \ 648 do { \ 649 current->trace_recursion &= \ 650 ~(3 << TRACE_GRAPH_DEPTH_START_BIT); \ 651 current->trace_recursion |= \ 652 ((depth) & 3) << TRACE_GRAPH_DEPTH_START_BIT; \ 653 } while (0) 654 655 #define TRACE_CONTEXT_BITS 4 656 657 #define TRACE_FTRACE_START TRACE_FTRACE_BIT 658 #define TRACE_FTRACE_MAX ((1 << (TRACE_FTRACE_START + TRACE_CONTEXT_BITS)) - 1) 659 660 #define TRACE_LIST_START TRACE_INTERNAL_BIT 661 #define TRACE_LIST_MAX ((1 << (TRACE_LIST_START + TRACE_CONTEXT_BITS)) - 1) 662 663 #define TRACE_CONTEXT_MASK TRACE_LIST_MAX 664 665 static __always_inline int trace_get_context_bit(void) 666 { 667 int bit; 668 669 if (in_interrupt()) { 670 if (in_nmi()) 671 bit = 0; 672 673 else if (in_irq()) 674 bit = 1; 675 else 676 bit = 2; 677 } else 678 bit = 3; 679 680 return bit; 681 } 682 683 static __always_inline int trace_test_and_set_recursion(int start, int max) 684 { 685 unsigned int val = current->trace_recursion; 686 int bit; 687 688 /* A previous recursion check was made */ 689 if ((val & TRACE_CONTEXT_MASK) > max) 690 return 0; 691 692 bit = trace_get_context_bit() + start; 693 if (unlikely(val & (1 << bit))) 694 return -1; 695 696 val |= 1 << bit; 697 current->trace_recursion = val; 698 barrier(); 699 700 return bit; 701 } 702 703 static __always_inline void trace_clear_recursion(int bit) 704 { 705 unsigned int val = current->trace_recursion; 706 707 if (!bit) 708 return; 709 710 bit = 1 << bit; 711 val &= ~bit; 712 713 barrier(); 714 current->trace_recursion = val; 715 } 716 717 static inline struct ring_buffer_iter * 718 trace_buffer_iter(struct trace_iterator *iter, int cpu) 719 { 720 return iter->buffer_iter ? iter->buffer_iter[cpu] : NULL; 721 } 722 723 int tracer_init(struct tracer *t, struct trace_array *tr); 724 int tracing_is_enabled(void); 725 void tracing_reset_online_cpus(struct array_buffer *buf); 726 void tracing_reset_current(int cpu); 727 void tracing_reset_all_online_cpus(void); 728 int tracing_open_generic(struct inode *inode, struct file *filp); 729 int tracing_open_generic_tr(struct inode *inode, struct file *filp); 730 bool tracing_is_disabled(void); 731 bool tracer_tracing_is_on(struct trace_array *tr); 732 void tracer_tracing_on(struct trace_array *tr); 733 void tracer_tracing_off(struct trace_array *tr); 734 struct dentry *trace_create_file(const char *name, 735 umode_t mode, 736 struct dentry *parent, 737 void *data, 738 const struct file_operations *fops); 739 740 struct dentry *tracing_init_dentry(void); 741 742 struct ring_buffer_event; 743 744 struct ring_buffer_event * 745 trace_buffer_lock_reserve(struct trace_buffer *buffer, 746 int type, 747 unsigned long len, 748 unsigned long flags, 749 int pc); 750 751 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr, 752 struct trace_array_cpu *data); 753 754 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, 755 int *ent_cpu, u64 *ent_ts); 756 757 void trace_buffer_unlock_commit_nostack(struct trace_buffer *buffer, 758 struct ring_buffer_event *event); 759 760 int trace_empty(struct trace_iterator *iter); 761 762 void *trace_find_next_entry_inc(struct trace_iterator *iter); 763 764 void trace_init_global_iter(struct trace_iterator *iter); 765 766 void tracing_iter_reset(struct trace_iterator *iter, int cpu); 767 768 unsigned long trace_total_entries_cpu(struct trace_array *tr, int cpu); 769 unsigned long trace_total_entries(struct trace_array *tr); 770 771 void trace_function(struct trace_array *tr, 772 unsigned long ip, 773 unsigned long parent_ip, 774 unsigned long flags, int pc); 775 void trace_graph_function(struct trace_array *tr, 776 unsigned long ip, 777 unsigned long parent_ip, 778 unsigned long flags, int pc); 779 void trace_latency_header(struct seq_file *m); 780 void trace_default_header(struct seq_file *m); 781 void print_trace_header(struct seq_file *m, struct trace_iterator *iter); 782 int trace_empty(struct trace_iterator *iter); 783 784 void trace_graph_return(struct ftrace_graph_ret *trace); 785 int trace_graph_entry(struct ftrace_graph_ent *trace); 786 void set_graph_array(struct trace_array *tr); 787 788 void tracing_start_cmdline_record(void); 789 void tracing_stop_cmdline_record(void); 790 void tracing_start_tgid_record(void); 791 void tracing_stop_tgid_record(void); 792 793 int register_tracer(struct tracer *type); 794 int is_tracing_stopped(void); 795 796 loff_t tracing_lseek(struct file *file, loff_t offset, int whence); 797 798 extern cpumask_var_t __read_mostly tracing_buffer_mask; 799 800 #define for_each_tracing_cpu(cpu) \ 801 for_each_cpu(cpu, tracing_buffer_mask) 802 803 extern unsigned long nsecs_to_usecs(unsigned long nsecs); 804 805 extern unsigned long tracing_thresh; 806 807 /* PID filtering */ 808 809 extern int pid_max; 810 811 bool trace_find_filtered_pid(struct trace_pid_list *filtered_pids, 812 pid_t search_pid); 813 bool trace_ignore_this_task(struct trace_pid_list *filtered_pids, 814 struct trace_pid_list *filtered_no_pids, 815 struct task_struct *task); 816 void trace_filter_add_remove_task(struct trace_pid_list *pid_list, 817 struct task_struct *self, 818 struct task_struct *task); 819 void *trace_pid_next(struct trace_pid_list *pid_list, void *v, loff_t *pos); 820 void *trace_pid_start(struct trace_pid_list *pid_list, loff_t *pos); 821 int trace_pid_show(struct seq_file *m, void *v); 822 void trace_free_pid_list(struct trace_pid_list *pid_list); 823 int trace_pid_write(struct trace_pid_list *filtered_pids, 824 struct trace_pid_list **new_pid_list, 825 const char __user *ubuf, size_t cnt); 826 827 #ifdef CONFIG_TRACER_MAX_TRACE 828 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu, 829 void *cond_data); 830 void update_max_tr_single(struct trace_array *tr, 831 struct task_struct *tsk, int cpu); 832 #endif /* CONFIG_TRACER_MAX_TRACE */ 833 834 #if (defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER)) && \ 835 defined(CONFIG_FSNOTIFY) 836 837 void latency_fsnotify(struct trace_array *tr); 838 839 #else 840 841 static inline void latency_fsnotify(struct trace_array *tr) { } 842 843 #endif 844 845 #ifdef CONFIG_STACKTRACE 846 void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, 847 int pc); 848 #else 849 static inline void __trace_stack(struct trace_array *tr, unsigned long flags, 850 int skip, int pc) 851 { 852 } 853 #endif /* CONFIG_STACKTRACE */ 854 855 extern u64 ftrace_now(int cpu); 856 857 extern void trace_find_cmdline(int pid, char comm[]); 858 extern int trace_find_tgid(int pid); 859 extern void trace_event_follow_fork(struct trace_array *tr, bool enable); 860 861 #ifdef CONFIG_DYNAMIC_FTRACE 862 extern unsigned long ftrace_update_tot_cnt; 863 extern unsigned long ftrace_number_of_pages; 864 extern unsigned long ftrace_number_of_groups; 865 void ftrace_init_trace_array(struct trace_array *tr); 866 #else 867 static inline void ftrace_init_trace_array(struct trace_array *tr) { } 868 #endif 869 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func 870 extern int DYN_FTRACE_TEST_NAME(void); 871 #define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2 872 extern int DYN_FTRACE_TEST_NAME2(void); 873 874 extern bool ring_buffer_expanded; 875 extern bool tracing_selftest_disabled; 876 877 #ifdef CONFIG_FTRACE_STARTUP_TEST 878 extern int trace_selftest_startup_function(struct tracer *trace, 879 struct trace_array *tr); 880 extern int trace_selftest_startup_function_graph(struct tracer *trace, 881 struct trace_array *tr); 882 extern int trace_selftest_startup_irqsoff(struct tracer *trace, 883 struct trace_array *tr); 884 extern int trace_selftest_startup_preemptoff(struct tracer *trace, 885 struct trace_array *tr); 886 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace, 887 struct trace_array *tr); 888 extern int trace_selftest_startup_wakeup(struct tracer *trace, 889 struct trace_array *tr); 890 extern int trace_selftest_startup_nop(struct tracer *trace, 891 struct trace_array *tr); 892 extern int trace_selftest_startup_branch(struct tracer *trace, 893 struct trace_array *tr); 894 /* 895 * Tracer data references selftest functions that only occur 896 * on boot up. These can be __init functions. Thus, when selftests 897 * are enabled, then the tracers need to reference __init functions. 898 */ 899 #define __tracer_data __refdata 900 #else 901 /* Tracers are seldom changed. Optimize when selftests are disabled. */ 902 #define __tracer_data __read_mostly 903 #endif /* CONFIG_FTRACE_STARTUP_TEST */ 904 905 extern void *head_page(struct trace_array_cpu *data); 906 extern unsigned long long ns2usecs(u64 nsec); 907 extern int 908 trace_vbprintk(unsigned long ip, const char *fmt, va_list args); 909 extern int 910 trace_vprintk(unsigned long ip, const char *fmt, va_list args); 911 extern int 912 trace_array_vprintk(struct trace_array *tr, 913 unsigned long ip, const char *fmt, va_list args); 914 int trace_array_printk_buf(struct trace_buffer *buffer, 915 unsigned long ip, const char *fmt, ...); 916 void trace_printk_seq(struct trace_seq *s); 917 enum print_line_t print_trace_line(struct trace_iterator *iter); 918 919 extern char trace_find_mark(unsigned long long duration); 920 921 struct ftrace_hash; 922 923 struct ftrace_mod_load { 924 struct list_head list; 925 char *func; 926 char *module; 927 int enable; 928 }; 929 930 enum { 931 FTRACE_HASH_FL_MOD = (1 << 0), 932 }; 933 934 struct ftrace_hash { 935 unsigned long size_bits; 936 struct hlist_head *buckets; 937 unsigned long count; 938 unsigned long flags; 939 struct rcu_head rcu; 940 }; 941 942 struct ftrace_func_entry * 943 ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip); 944 945 static __always_inline bool ftrace_hash_empty(struct ftrace_hash *hash) 946 { 947 return !hash || !(hash->count || (hash->flags & FTRACE_HASH_FL_MOD)); 948 } 949 950 /* Standard output formatting function used for function return traces */ 951 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 952 953 /* Flag options */ 954 #define TRACE_GRAPH_PRINT_OVERRUN 0x1 955 #define TRACE_GRAPH_PRINT_CPU 0x2 956 #define TRACE_GRAPH_PRINT_OVERHEAD 0x4 957 #define TRACE_GRAPH_PRINT_PROC 0x8 958 #define TRACE_GRAPH_PRINT_DURATION 0x10 959 #define TRACE_GRAPH_PRINT_ABS_TIME 0x20 960 #define TRACE_GRAPH_PRINT_REL_TIME 0x40 961 #define TRACE_GRAPH_PRINT_IRQS 0x80 962 #define TRACE_GRAPH_PRINT_TAIL 0x100 963 #define TRACE_GRAPH_SLEEP_TIME 0x200 964 #define TRACE_GRAPH_GRAPH_TIME 0x400 965 #define TRACE_GRAPH_PRINT_FILL_SHIFT 28 966 #define TRACE_GRAPH_PRINT_FILL_MASK (0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT) 967 968 extern void ftrace_graph_sleep_time_control(bool enable); 969 970 #ifdef CONFIG_FUNCTION_PROFILER 971 extern void ftrace_graph_graph_time_control(bool enable); 972 #else 973 static inline void ftrace_graph_graph_time_control(bool enable) { } 974 #endif 975 976 extern enum print_line_t 977 print_graph_function_flags(struct trace_iterator *iter, u32 flags); 978 extern void print_graph_headers_flags(struct seq_file *s, u32 flags); 979 extern void 980 trace_print_graph_duration(unsigned long long duration, struct trace_seq *s); 981 extern void graph_trace_open(struct trace_iterator *iter); 982 extern void graph_trace_close(struct trace_iterator *iter); 983 extern int __trace_graph_entry(struct trace_array *tr, 984 struct ftrace_graph_ent *trace, 985 unsigned long flags, int pc); 986 extern void __trace_graph_return(struct trace_array *tr, 987 struct ftrace_graph_ret *trace, 988 unsigned long flags, int pc); 989 990 #ifdef CONFIG_DYNAMIC_FTRACE 991 extern struct ftrace_hash __rcu *ftrace_graph_hash; 992 extern struct ftrace_hash __rcu *ftrace_graph_notrace_hash; 993 994 static inline int ftrace_graph_addr(struct ftrace_graph_ent *trace) 995 { 996 unsigned long addr = trace->func; 997 int ret = 0; 998 struct ftrace_hash *hash; 999 1000 preempt_disable_notrace(); 1001 1002 /* 1003 * Have to open code "rcu_dereference_sched()" because the 1004 * function graph tracer can be called when RCU is not 1005 * "watching". 1006 * Protected with schedule_on_each_cpu(ftrace_sync) 1007 */ 1008 hash = rcu_dereference_protected(ftrace_graph_hash, !preemptible()); 1009 1010 if (ftrace_hash_empty(hash)) { 1011 ret = 1; 1012 goto out; 1013 } 1014 1015 if (ftrace_lookup_ip(hash, addr)) { 1016 1017 /* 1018 * This needs to be cleared on the return functions 1019 * when the depth is zero. 1020 */ 1021 trace_recursion_set(TRACE_GRAPH_BIT); 1022 trace_recursion_set_depth(trace->depth); 1023 1024 /* 1025 * If no irqs are to be traced, but a set_graph_function 1026 * is set, and called by an interrupt handler, we still 1027 * want to trace it. 1028 */ 1029 if (in_irq()) 1030 trace_recursion_set(TRACE_IRQ_BIT); 1031 else 1032 trace_recursion_clear(TRACE_IRQ_BIT); 1033 ret = 1; 1034 } 1035 1036 out: 1037 preempt_enable_notrace(); 1038 return ret; 1039 } 1040 1041 static inline void ftrace_graph_addr_finish(struct ftrace_graph_ret *trace) 1042 { 1043 if (trace_recursion_test(TRACE_GRAPH_BIT) && 1044 trace->depth == trace_recursion_depth()) 1045 trace_recursion_clear(TRACE_GRAPH_BIT); 1046 } 1047 1048 static inline int ftrace_graph_notrace_addr(unsigned long addr) 1049 { 1050 int ret = 0; 1051 struct ftrace_hash *notrace_hash; 1052 1053 preempt_disable_notrace(); 1054 1055 /* 1056 * Have to open code "rcu_dereference_sched()" because the 1057 * function graph tracer can be called when RCU is not 1058 * "watching". 1059 * Protected with schedule_on_each_cpu(ftrace_sync) 1060 */ 1061 notrace_hash = rcu_dereference_protected(ftrace_graph_notrace_hash, 1062 !preemptible()); 1063 1064 if (ftrace_lookup_ip(notrace_hash, addr)) 1065 ret = 1; 1066 1067 preempt_enable_notrace(); 1068 return ret; 1069 } 1070 #else 1071 static inline int ftrace_graph_addr(struct ftrace_graph_ent *trace) 1072 { 1073 return 1; 1074 } 1075 1076 static inline int ftrace_graph_notrace_addr(unsigned long addr) 1077 { 1078 return 0; 1079 } 1080 static inline void ftrace_graph_addr_finish(struct ftrace_graph_ret *trace) 1081 { } 1082 #endif /* CONFIG_DYNAMIC_FTRACE */ 1083 1084 extern unsigned int fgraph_max_depth; 1085 1086 static inline bool ftrace_graph_ignore_func(struct ftrace_graph_ent *trace) 1087 { 1088 /* trace it when it is-nested-in or is a function enabled. */ 1089 return !(trace_recursion_test(TRACE_GRAPH_BIT) || 1090 ftrace_graph_addr(trace)) || 1091 (trace->depth < 0) || 1092 (fgraph_max_depth && trace->depth >= fgraph_max_depth); 1093 } 1094 1095 #else /* CONFIG_FUNCTION_GRAPH_TRACER */ 1096 static inline enum print_line_t 1097 print_graph_function_flags(struct trace_iterator *iter, u32 flags) 1098 { 1099 return TRACE_TYPE_UNHANDLED; 1100 } 1101 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ 1102 1103 extern struct list_head ftrace_pids; 1104 1105 #ifdef CONFIG_FUNCTION_TRACER 1106 1107 #define FTRACE_PID_IGNORE -1 1108 #define FTRACE_PID_TRACE -2 1109 1110 struct ftrace_func_command { 1111 struct list_head list; 1112 char *name; 1113 int (*func)(struct trace_array *tr, 1114 struct ftrace_hash *hash, 1115 char *func, char *cmd, 1116 char *params, int enable); 1117 }; 1118 extern bool ftrace_filter_param __initdata; 1119 static inline int ftrace_trace_task(struct trace_array *tr) 1120 { 1121 return this_cpu_read(tr->array_buffer.data->ftrace_ignore_pid) != 1122 FTRACE_PID_IGNORE; 1123 } 1124 extern int ftrace_is_dead(void); 1125 int ftrace_create_function_files(struct trace_array *tr, 1126 struct dentry *parent); 1127 void ftrace_destroy_function_files(struct trace_array *tr); 1128 void ftrace_init_global_array_ops(struct trace_array *tr); 1129 void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func); 1130 void ftrace_reset_array_ops(struct trace_array *tr); 1131 void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer); 1132 void ftrace_init_tracefs_toplevel(struct trace_array *tr, 1133 struct dentry *d_tracer); 1134 void ftrace_clear_pids(struct trace_array *tr); 1135 int init_function_trace(void); 1136 void ftrace_pid_follow_fork(struct trace_array *tr, bool enable); 1137 #else 1138 static inline int ftrace_trace_task(struct trace_array *tr) 1139 { 1140 return 1; 1141 } 1142 static inline int ftrace_is_dead(void) { return 0; } 1143 static inline int 1144 ftrace_create_function_files(struct trace_array *tr, 1145 struct dentry *parent) 1146 { 1147 return 0; 1148 } 1149 static inline void ftrace_destroy_function_files(struct trace_array *tr) { } 1150 static inline __init void 1151 ftrace_init_global_array_ops(struct trace_array *tr) { } 1152 static inline void ftrace_reset_array_ops(struct trace_array *tr) { } 1153 static inline void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d) { } 1154 static inline void ftrace_init_tracefs_toplevel(struct trace_array *tr, struct dentry *d) { } 1155 static inline void ftrace_clear_pids(struct trace_array *tr) { } 1156 static inline int init_function_trace(void) { return 0; } 1157 static inline void ftrace_pid_follow_fork(struct trace_array *tr, bool enable) { } 1158 /* ftace_func_t type is not defined, use macro instead of static inline */ 1159 #define ftrace_init_array_ops(tr, func) do { } while (0) 1160 #endif /* CONFIG_FUNCTION_TRACER */ 1161 1162 #if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE) 1163 1164 struct ftrace_probe_ops { 1165 void (*func)(unsigned long ip, 1166 unsigned long parent_ip, 1167 struct trace_array *tr, 1168 struct ftrace_probe_ops *ops, 1169 void *data); 1170 int (*init)(struct ftrace_probe_ops *ops, 1171 struct trace_array *tr, 1172 unsigned long ip, void *init_data, 1173 void **data); 1174 void (*free)(struct ftrace_probe_ops *ops, 1175 struct trace_array *tr, 1176 unsigned long ip, void *data); 1177 int (*print)(struct seq_file *m, 1178 unsigned long ip, 1179 struct ftrace_probe_ops *ops, 1180 void *data); 1181 }; 1182 1183 struct ftrace_func_mapper; 1184 typedef int (*ftrace_mapper_func)(void *data); 1185 1186 struct ftrace_func_mapper *allocate_ftrace_func_mapper(void); 1187 void **ftrace_func_mapper_find_ip(struct ftrace_func_mapper *mapper, 1188 unsigned long ip); 1189 int ftrace_func_mapper_add_ip(struct ftrace_func_mapper *mapper, 1190 unsigned long ip, void *data); 1191 void *ftrace_func_mapper_remove_ip(struct ftrace_func_mapper *mapper, 1192 unsigned long ip); 1193 void free_ftrace_func_mapper(struct ftrace_func_mapper *mapper, 1194 ftrace_mapper_func free_func); 1195 1196 extern int 1197 register_ftrace_function_probe(char *glob, struct trace_array *tr, 1198 struct ftrace_probe_ops *ops, void *data); 1199 extern int 1200 unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr, 1201 struct ftrace_probe_ops *ops); 1202 extern void clear_ftrace_function_probes(struct trace_array *tr); 1203 1204 int register_ftrace_command(struct ftrace_func_command *cmd); 1205 int unregister_ftrace_command(struct ftrace_func_command *cmd); 1206 1207 void ftrace_create_filter_files(struct ftrace_ops *ops, 1208 struct dentry *parent); 1209 void ftrace_destroy_filter_files(struct ftrace_ops *ops); 1210 1211 extern int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf, 1212 int len, int reset); 1213 extern int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf, 1214 int len, int reset); 1215 #else 1216 struct ftrace_func_command; 1217 1218 static inline __init int register_ftrace_command(struct ftrace_func_command *cmd) 1219 { 1220 return -EINVAL; 1221 } 1222 static inline __init int unregister_ftrace_command(char *cmd_name) 1223 { 1224 return -EINVAL; 1225 } 1226 static inline void clear_ftrace_function_probes(struct trace_array *tr) 1227 { 1228 } 1229 1230 /* 1231 * The ops parameter passed in is usually undefined. 1232 * This must be a macro. 1233 */ 1234 #define ftrace_create_filter_files(ops, parent) do { } while (0) 1235 #define ftrace_destroy_filter_files(ops) do { } while (0) 1236 #endif /* CONFIG_FUNCTION_TRACER && CONFIG_DYNAMIC_FTRACE */ 1237 1238 bool ftrace_event_is_function(struct trace_event_call *call); 1239 1240 /* 1241 * struct trace_parser - servers for reading the user input separated by spaces 1242 * @cont: set if the input is not complete - no final space char was found 1243 * @buffer: holds the parsed user input 1244 * @idx: user input length 1245 * @size: buffer size 1246 */ 1247 struct trace_parser { 1248 bool cont; 1249 char *buffer; 1250 unsigned idx; 1251 unsigned size; 1252 }; 1253 1254 static inline bool trace_parser_loaded(struct trace_parser *parser) 1255 { 1256 return (parser->idx != 0); 1257 } 1258 1259 static inline bool trace_parser_cont(struct trace_parser *parser) 1260 { 1261 return parser->cont; 1262 } 1263 1264 static inline void trace_parser_clear(struct trace_parser *parser) 1265 { 1266 parser->cont = false; 1267 parser->idx = 0; 1268 } 1269 1270 extern int trace_parser_get_init(struct trace_parser *parser, int size); 1271 extern void trace_parser_put(struct trace_parser *parser); 1272 extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf, 1273 size_t cnt, loff_t *ppos); 1274 1275 /* 1276 * Only create function graph options if function graph is configured. 1277 */ 1278 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 1279 # define FGRAPH_FLAGS \ 1280 C(DISPLAY_GRAPH, "display-graph"), 1281 #else 1282 # define FGRAPH_FLAGS 1283 #endif 1284 1285 #ifdef CONFIG_BRANCH_TRACER 1286 # define BRANCH_FLAGS \ 1287 C(BRANCH, "branch"), 1288 #else 1289 # define BRANCH_FLAGS 1290 #endif 1291 1292 #ifdef CONFIG_FUNCTION_TRACER 1293 # define FUNCTION_FLAGS \ 1294 C(FUNCTION, "function-trace"), \ 1295 C(FUNC_FORK, "function-fork"), 1296 # define FUNCTION_DEFAULT_FLAGS TRACE_ITER_FUNCTION 1297 #else 1298 # define FUNCTION_FLAGS 1299 # define FUNCTION_DEFAULT_FLAGS 0UL 1300 # define TRACE_ITER_FUNC_FORK 0UL 1301 #endif 1302 1303 #ifdef CONFIG_STACKTRACE 1304 # define STACK_FLAGS \ 1305 C(STACKTRACE, "stacktrace"), 1306 #else 1307 # define STACK_FLAGS 1308 #endif 1309 1310 /* 1311 * trace_iterator_flags is an enumeration that defines bit 1312 * positions into trace_flags that controls the output. 1313 * 1314 * NOTE: These bits must match the trace_options array in 1315 * trace.c (this macro guarantees it). 1316 */ 1317 #define TRACE_FLAGS \ 1318 C(PRINT_PARENT, "print-parent"), \ 1319 C(SYM_OFFSET, "sym-offset"), \ 1320 C(SYM_ADDR, "sym-addr"), \ 1321 C(VERBOSE, "verbose"), \ 1322 C(RAW, "raw"), \ 1323 C(HEX, "hex"), \ 1324 C(BIN, "bin"), \ 1325 C(BLOCK, "block"), \ 1326 C(PRINTK, "trace_printk"), \ 1327 C(ANNOTATE, "annotate"), \ 1328 C(USERSTACKTRACE, "userstacktrace"), \ 1329 C(SYM_USEROBJ, "sym-userobj"), \ 1330 C(PRINTK_MSGONLY, "printk-msg-only"), \ 1331 C(CONTEXT_INFO, "context-info"), /* Print pid/cpu/time */ \ 1332 C(LATENCY_FMT, "latency-format"), \ 1333 C(RECORD_CMD, "record-cmd"), \ 1334 C(RECORD_TGID, "record-tgid"), \ 1335 C(OVERWRITE, "overwrite"), \ 1336 C(STOP_ON_FREE, "disable_on_free"), \ 1337 C(IRQ_INFO, "irq-info"), \ 1338 C(MARKERS, "markers"), \ 1339 C(EVENT_FORK, "event-fork"), \ 1340 C(PAUSE_ON_TRACE, "pause-on-trace"), \ 1341 FUNCTION_FLAGS \ 1342 FGRAPH_FLAGS \ 1343 STACK_FLAGS \ 1344 BRANCH_FLAGS 1345 1346 /* 1347 * By defining C, we can make TRACE_FLAGS a list of bit names 1348 * that will define the bits for the flag masks. 1349 */ 1350 #undef C 1351 #define C(a, b) TRACE_ITER_##a##_BIT 1352 1353 enum trace_iterator_bits { 1354 TRACE_FLAGS 1355 /* Make sure we don't go more than we have bits for */ 1356 TRACE_ITER_LAST_BIT 1357 }; 1358 1359 /* 1360 * By redefining C, we can make TRACE_FLAGS a list of masks that 1361 * use the bits as defined above. 1362 */ 1363 #undef C 1364 #define C(a, b) TRACE_ITER_##a = (1 << TRACE_ITER_##a##_BIT) 1365 1366 enum trace_iterator_flags { TRACE_FLAGS }; 1367 1368 /* 1369 * TRACE_ITER_SYM_MASK masks the options in trace_flags that 1370 * control the output of kernel symbols. 1371 */ 1372 #define TRACE_ITER_SYM_MASK \ 1373 (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR) 1374 1375 extern struct tracer nop_trace; 1376 1377 #ifdef CONFIG_BRANCH_TRACER 1378 extern int enable_branch_tracing(struct trace_array *tr); 1379 extern void disable_branch_tracing(void); 1380 static inline int trace_branch_enable(struct trace_array *tr) 1381 { 1382 if (tr->trace_flags & TRACE_ITER_BRANCH) 1383 return enable_branch_tracing(tr); 1384 return 0; 1385 } 1386 static inline void trace_branch_disable(void) 1387 { 1388 /* due to races, always disable */ 1389 disable_branch_tracing(); 1390 } 1391 #else 1392 static inline int trace_branch_enable(struct trace_array *tr) 1393 { 1394 return 0; 1395 } 1396 static inline void trace_branch_disable(void) 1397 { 1398 } 1399 #endif /* CONFIG_BRANCH_TRACER */ 1400 1401 /* set ring buffers to default size if not already done so */ 1402 int tracing_update_buffers(void); 1403 1404 struct ftrace_event_field { 1405 struct list_head link; 1406 const char *name; 1407 const char *type; 1408 int filter_type; 1409 int offset; 1410 int size; 1411 int is_signed; 1412 }; 1413 1414 struct prog_entry; 1415 1416 struct event_filter { 1417 struct prog_entry __rcu *prog; 1418 char *filter_string; 1419 }; 1420 1421 struct event_subsystem { 1422 struct list_head list; 1423 const char *name; 1424 struct event_filter *filter; 1425 int ref_count; 1426 }; 1427 1428 struct trace_subsystem_dir { 1429 struct list_head list; 1430 struct event_subsystem *subsystem; 1431 struct trace_array *tr; 1432 struct dentry *entry; 1433 int ref_count; 1434 int nr_events; 1435 }; 1436 1437 extern int call_filter_check_discard(struct trace_event_call *call, void *rec, 1438 struct trace_buffer *buffer, 1439 struct ring_buffer_event *event); 1440 1441 void trace_buffer_unlock_commit_regs(struct trace_array *tr, 1442 struct trace_buffer *buffer, 1443 struct ring_buffer_event *event, 1444 unsigned long flags, int pc, 1445 struct pt_regs *regs); 1446 1447 static inline void trace_buffer_unlock_commit(struct trace_array *tr, 1448 struct trace_buffer *buffer, 1449 struct ring_buffer_event *event, 1450 unsigned long flags, int pc) 1451 { 1452 trace_buffer_unlock_commit_regs(tr, buffer, event, flags, pc, NULL); 1453 } 1454 1455 DECLARE_PER_CPU(struct ring_buffer_event *, trace_buffered_event); 1456 DECLARE_PER_CPU(int, trace_buffered_event_cnt); 1457 void trace_buffered_event_disable(void); 1458 void trace_buffered_event_enable(void); 1459 1460 static inline void 1461 __trace_event_discard_commit(struct trace_buffer *buffer, 1462 struct ring_buffer_event *event) 1463 { 1464 if (this_cpu_read(trace_buffered_event) == event) { 1465 /* Simply release the temp buffer */ 1466 this_cpu_dec(trace_buffered_event_cnt); 1467 return; 1468 } 1469 ring_buffer_discard_commit(buffer, event); 1470 } 1471 1472 /* 1473 * Helper function for event_trigger_unlock_commit{_regs}(). 1474 * If there are event triggers attached to this event that requires 1475 * filtering against its fields, then they wil be called as the 1476 * entry already holds the field information of the current event. 1477 * 1478 * It also checks if the event should be discarded or not. 1479 * It is to be discarded if the event is soft disabled and the 1480 * event was only recorded to process triggers, or if the event 1481 * filter is active and this event did not match the filters. 1482 * 1483 * Returns true if the event is discarded, false otherwise. 1484 */ 1485 static inline bool 1486 __event_trigger_test_discard(struct trace_event_file *file, 1487 struct trace_buffer *buffer, 1488 struct ring_buffer_event *event, 1489 void *entry, 1490 enum event_trigger_type *tt) 1491 { 1492 unsigned long eflags = file->flags; 1493 1494 if (eflags & EVENT_FILE_FL_TRIGGER_COND) 1495 *tt = event_triggers_call(file, entry, event); 1496 1497 if (test_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &file->flags) || 1498 (unlikely(file->flags & EVENT_FILE_FL_FILTERED) && 1499 !filter_match_preds(file->filter, entry))) { 1500 __trace_event_discard_commit(buffer, event); 1501 return true; 1502 } 1503 1504 return false; 1505 } 1506 1507 /** 1508 * event_trigger_unlock_commit - handle triggers and finish event commit 1509 * @file: The file pointer assoctiated to the event 1510 * @buffer: The ring buffer that the event is being written to 1511 * @event: The event meta data in the ring buffer 1512 * @entry: The event itself 1513 * @irq_flags: The state of the interrupts at the start of the event 1514 * @pc: The state of the preempt count at the start of the event. 1515 * 1516 * This is a helper function to handle triggers that require data 1517 * from the event itself. It also tests the event against filters and 1518 * if the event is soft disabled and should be discarded. 1519 */ 1520 static inline void 1521 event_trigger_unlock_commit(struct trace_event_file *file, 1522 struct trace_buffer *buffer, 1523 struct ring_buffer_event *event, 1524 void *entry, unsigned long irq_flags, int pc) 1525 { 1526 enum event_trigger_type tt = ETT_NONE; 1527 1528 if (!__event_trigger_test_discard(file, buffer, event, entry, &tt)) 1529 trace_buffer_unlock_commit(file->tr, buffer, event, irq_flags, pc); 1530 1531 if (tt) 1532 event_triggers_post_call(file, tt); 1533 } 1534 1535 /** 1536 * event_trigger_unlock_commit_regs - handle triggers and finish event commit 1537 * @file: The file pointer assoctiated to 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 * @irq_flags: The state of the interrupts at the start of the event 1542 * @pc: The state of the preempt count at the start of the event. 1543 * 1544 * This is a helper function to handle triggers that require data 1545 * from the event itself. It also tests the event against filters and 1546 * if the event is soft disabled and should be discarded. 1547 * 1548 * Same as event_trigger_unlock_commit() but calls 1549 * trace_buffer_unlock_commit_regs() instead of trace_buffer_unlock_commit(). 1550 */ 1551 static inline void 1552 event_trigger_unlock_commit_regs(struct trace_event_file *file, 1553 struct trace_buffer *buffer, 1554 struct ring_buffer_event *event, 1555 void *entry, unsigned long irq_flags, int pc, 1556 struct pt_regs *regs) 1557 { 1558 enum event_trigger_type tt = ETT_NONE; 1559 1560 if (!__event_trigger_test_discard(file, buffer, event, entry, &tt)) 1561 trace_buffer_unlock_commit_regs(file->tr, buffer, event, 1562 irq_flags, pc, regs); 1563 1564 if (tt) 1565 event_triggers_post_call(file, tt); 1566 } 1567 1568 #define FILTER_PRED_INVALID ((unsigned short)-1) 1569 #define FILTER_PRED_IS_RIGHT (1 << 15) 1570 #define FILTER_PRED_FOLD (1 << 15) 1571 1572 /* 1573 * The max preds is the size of unsigned short with 1574 * two flags at the MSBs. One bit is used for both the IS_RIGHT 1575 * and FOLD flags. The other is reserved. 1576 * 1577 * 2^14 preds is way more than enough. 1578 */ 1579 #define MAX_FILTER_PRED 16384 1580 1581 struct filter_pred; 1582 struct regex; 1583 1584 typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event); 1585 1586 typedef int (*regex_match_func)(char *str, struct regex *r, int len); 1587 1588 enum regex_type { 1589 MATCH_FULL = 0, 1590 MATCH_FRONT_ONLY, 1591 MATCH_MIDDLE_ONLY, 1592 MATCH_END_ONLY, 1593 MATCH_GLOB, 1594 MATCH_INDEX, 1595 }; 1596 1597 struct regex { 1598 char pattern[MAX_FILTER_STR_VAL]; 1599 int len; 1600 int field_len; 1601 regex_match_func match; 1602 }; 1603 1604 struct filter_pred { 1605 filter_pred_fn_t fn; 1606 u64 val; 1607 struct regex regex; 1608 unsigned short *ops; 1609 struct ftrace_event_field *field; 1610 int offset; 1611 int not; 1612 int op; 1613 }; 1614 1615 static inline bool is_string_field(struct ftrace_event_field *field) 1616 { 1617 return field->filter_type == FILTER_DYN_STRING || 1618 field->filter_type == FILTER_STATIC_STRING || 1619 field->filter_type == FILTER_PTR_STRING || 1620 field->filter_type == FILTER_COMM; 1621 } 1622 1623 static inline bool is_function_field(struct ftrace_event_field *field) 1624 { 1625 return field->filter_type == FILTER_TRACE_FN; 1626 } 1627 1628 extern enum regex_type 1629 filter_parse_regex(char *buff, int len, char **search, int *not); 1630 extern void print_event_filter(struct trace_event_file *file, 1631 struct trace_seq *s); 1632 extern int apply_event_filter(struct trace_event_file *file, 1633 char *filter_string); 1634 extern int apply_subsystem_event_filter(struct trace_subsystem_dir *dir, 1635 char *filter_string); 1636 extern void print_subsystem_event_filter(struct event_subsystem *system, 1637 struct trace_seq *s); 1638 extern int filter_assign_type(const char *type); 1639 extern int create_event_filter(struct trace_array *tr, 1640 struct trace_event_call *call, 1641 char *filter_str, bool set_str, 1642 struct event_filter **filterp); 1643 extern void free_event_filter(struct event_filter *filter); 1644 1645 struct ftrace_event_field * 1646 trace_find_event_field(struct trace_event_call *call, char *name); 1647 1648 extern void trace_event_enable_cmd_record(bool enable); 1649 extern void trace_event_enable_tgid_record(bool enable); 1650 1651 extern int event_trace_init(void); 1652 extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr); 1653 extern int event_trace_del_tracer(struct trace_array *tr); 1654 1655 extern struct trace_event_file *__find_event_file(struct trace_array *tr, 1656 const char *system, 1657 const char *event); 1658 extern struct trace_event_file *find_event_file(struct trace_array *tr, 1659 const char *system, 1660 const char *event); 1661 1662 static inline void *event_file_data(struct file *filp) 1663 { 1664 return READ_ONCE(file_inode(filp)->i_private); 1665 } 1666 1667 extern struct mutex event_mutex; 1668 extern struct list_head ftrace_events; 1669 1670 extern const struct file_operations event_trigger_fops; 1671 extern const struct file_operations event_hist_fops; 1672 extern const struct file_operations event_hist_debug_fops; 1673 extern const struct file_operations event_inject_fops; 1674 1675 #ifdef CONFIG_HIST_TRIGGERS 1676 extern int register_trigger_hist_cmd(void); 1677 extern int register_trigger_hist_enable_disable_cmds(void); 1678 #else 1679 static inline int register_trigger_hist_cmd(void) { return 0; } 1680 static inline int register_trigger_hist_enable_disable_cmds(void) { return 0; } 1681 #endif 1682 1683 extern int register_trigger_cmds(void); 1684 extern void clear_event_triggers(struct trace_array *tr); 1685 1686 struct event_trigger_data { 1687 unsigned long count; 1688 int ref; 1689 struct event_trigger_ops *ops; 1690 struct event_command *cmd_ops; 1691 struct event_filter __rcu *filter; 1692 char *filter_str; 1693 void *private_data; 1694 bool paused; 1695 bool paused_tmp; 1696 struct list_head list; 1697 char *name; 1698 struct list_head named_list; 1699 struct event_trigger_data *named_data; 1700 }; 1701 1702 /* Avoid typos */ 1703 #define ENABLE_EVENT_STR "enable_event" 1704 #define DISABLE_EVENT_STR "disable_event" 1705 #define ENABLE_HIST_STR "enable_hist" 1706 #define DISABLE_HIST_STR "disable_hist" 1707 1708 struct enable_trigger_data { 1709 struct trace_event_file *file; 1710 bool enable; 1711 bool hist; 1712 }; 1713 1714 extern int event_enable_trigger_print(struct seq_file *m, 1715 struct event_trigger_ops *ops, 1716 struct event_trigger_data *data); 1717 extern void event_enable_trigger_free(struct event_trigger_ops *ops, 1718 struct event_trigger_data *data); 1719 extern int event_enable_trigger_func(struct event_command *cmd_ops, 1720 struct trace_event_file *file, 1721 char *glob, char *cmd, char *param); 1722 extern int event_enable_register_trigger(char *glob, 1723 struct event_trigger_ops *ops, 1724 struct event_trigger_data *data, 1725 struct trace_event_file *file); 1726 extern void event_enable_unregister_trigger(char *glob, 1727 struct event_trigger_ops *ops, 1728 struct event_trigger_data *test, 1729 struct trace_event_file *file); 1730 extern void trigger_data_free(struct event_trigger_data *data); 1731 extern int event_trigger_init(struct event_trigger_ops *ops, 1732 struct event_trigger_data *data); 1733 extern int trace_event_trigger_enable_disable(struct trace_event_file *file, 1734 int trigger_enable); 1735 extern void update_cond_flag(struct trace_event_file *file); 1736 extern int set_trigger_filter(char *filter_str, 1737 struct event_trigger_data *trigger_data, 1738 struct trace_event_file *file); 1739 extern struct event_trigger_data *find_named_trigger(const char *name); 1740 extern bool is_named_trigger(struct event_trigger_data *test); 1741 extern int save_named_trigger(const char *name, 1742 struct event_trigger_data *data); 1743 extern void del_named_trigger(struct event_trigger_data *data); 1744 extern void pause_named_trigger(struct event_trigger_data *data); 1745 extern void unpause_named_trigger(struct event_trigger_data *data); 1746 extern void set_named_trigger_data(struct event_trigger_data *data, 1747 struct event_trigger_data *named_data); 1748 extern struct event_trigger_data * 1749 get_named_trigger_data(struct event_trigger_data *data); 1750 extern int register_event_command(struct event_command *cmd); 1751 extern int unregister_event_command(struct event_command *cmd); 1752 extern int register_trigger_hist_enable_disable_cmds(void); 1753 1754 /** 1755 * struct event_trigger_ops - callbacks for trace event triggers 1756 * 1757 * The methods in this structure provide per-event trigger hooks for 1758 * various trigger operations. 1759 * 1760 * All the methods below, except for @init() and @free(), must be 1761 * implemented. 1762 * 1763 * @func: The trigger 'probe' function called when the triggering 1764 * event occurs. The data passed into this callback is the data 1765 * that was supplied to the event_command @reg() function that 1766 * registered the trigger (see struct event_command) along with 1767 * the trace record, rec. 1768 * 1769 * @init: An optional initialization function called for the trigger 1770 * when the trigger is registered (via the event_command reg() 1771 * function). This can be used to perform per-trigger 1772 * initialization such as incrementing a per-trigger reference 1773 * count, for instance. This is usually implemented by the 1774 * generic utility function @event_trigger_init() (see 1775 * trace_event_triggers.c). 1776 * 1777 * @free: An optional de-initialization function called for the 1778 * trigger when the trigger is unregistered (via the 1779 * event_command @reg() function). This can be used to perform 1780 * per-trigger de-initialization such as decrementing a 1781 * per-trigger reference count and freeing corresponding trigger 1782 * data, for instance. This is usually implemented by the 1783 * generic utility function @event_trigger_free() (see 1784 * trace_event_triggers.c). 1785 * 1786 * @print: The callback function invoked to have the trigger print 1787 * itself. This is usually implemented by a wrapper function 1788 * that calls the generic utility function @event_trigger_print() 1789 * (see trace_event_triggers.c). 1790 */ 1791 struct event_trigger_ops { 1792 void (*func)(struct event_trigger_data *data, 1793 void *rec, 1794 struct ring_buffer_event *rbe); 1795 int (*init)(struct event_trigger_ops *ops, 1796 struct event_trigger_data *data); 1797 void (*free)(struct event_trigger_ops *ops, 1798 struct event_trigger_data *data); 1799 int (*print)(struct seq_file *m, 1800 struct event_trigger_ops *ops, 1801 struct event_trigger_data *data); 1802 }; 1803 1804 /** 1805 * struct event_command - callbacks and data members for event commands 1806 * 1807 * Event commands are invoked by users by writing the command name 1808 * into the 'trigger' file associated with a trace event. The 1809 * parameters associated with a specific invocation of an event 1810 * command are used to create an event trigger instance, which is 1811 * added to the list of trigger instances associated with that trace 1812 * event. When the event is hit, the set of triggers associated with 1813 * that event is invoked. 1814 * 1815 * The data members in this structure provide per-event command data 1816 * for various event commands. 1817 * 1818 * All the data members below, except for @post_trigger, must be set 1819 * for each event command. 1820 * 1821 * @name: The unique name that identifies the event command. This is 1822 * the name used when setting triggers via trigger files. 1823 * 1824 * @trigger_type: A unique id that identifies the event command 1825 * 'type'. This value has two purposes, the first to ensure that 1826 * only one trigger of the same type can be set at a given time 1827 * for a particular event e.g. it doesn't make sense to have both 1828 * a traceon and traceoff trigger attached to a single event at 1829 * the same time, so traceon and traceoff have the same type 1830 * though they have different names. The @trigger_type value is 1831 * also used as a bit value for deferring the actual trigger 1832 * action until after the current event is finished. Some 1833 * commands need to do this if they themselves log to the trace 1834 * buffer (see the @post_trigger() member below). @trigger_type 1835 * values are defined by adding new values to the trigger_type 1836 * enum in include/linux/trace_events.h. 1837 * 1838 * @flags: See the enum event_command_flags below. 1839 * 1840 * All the methods below, except for @set_filter() and @unreg_all(), 1841 * must be implemented. 1842 * 1843 * @func: The callback function responsible for parsing and 1844 * registering the trigger written to the 'trigger' file by the 1845 * user. It allocates the trigger instance and registers it with 1846 * the appropriate trace event. It makes use of the other 1847 * event_command callback functions to orchestrate this, and is 1848 * usually implemented by the generic utility function 1849 * @event_trigger_callback() (see trace_event_triggers.c). 1850 * 1851 * @reg: Adds the trigger to the list of triggers associated with the 1852 * event, and enables the event trigger itself, after 1853 * initializing it (via the event_trigger_ops @init() function). 1854 * This is also where commands can use the @trigger_type value to 1855 * make the decision as to whether or not multiple instances of 1856 * the trigger should be allowed. This is usually implemented by 1857 * the generic utility function @register_trigger() (see 1858 * trace_event_triggers.c). 1859 * 1860 * @unreg: Removes the trigger from the list of triggers associated 1861 * with the event, and disables the event trigger itself, after 1862 * initializing it (via the event_trigger_ops @free() function). 1863 * This is usually implemented by the generic utility function 1864 * @unregister_trigger() (see trace_event_triggers.c). 1865 * 1866 * @unreg_all: An optional function called to remove all the triggers 1867 * from the list of triggers associated with the event. Called 1868 * when a trigger file is opened in truncate mode. 1869 * 1870 * @set_filter: An optional function called to parse and set a filter 1871 * for the trigger. If no @set_filter() method is set for the 1872 * event command, filters set by the user for the command will be 1873 * ignored. This is usually implemented by the generic utility 1874 * function @set_trigger_filter() (see trace_event_triggers.c). 1875 * 1876 * @get_trigger_ops: The callback function invoked to retrieve the 1877 * event_trigger_ops implementation associated with the command. 1878 */ 1879 struct event_command { 1880 struct list_head list; 1881 char *name; 1882 enum event_trigger_type trigger_type; 1883 int flags; 1884 int (*func)(struct event_command *cmd_ops, 1885 struct trace_event_file *file, 1886 char *glob, char *cmd, char *params); 1887 int (*reg)(char *glob, 1888 struct event_trigger_ops *ops, 1889 struct event_trigger_data *data, 1890 struct trace_event_file *file); 1891 void (*unreg)(char *glob, 1892 struct event_trigger_ops *ops, 1893 struct event_trigger_data *data, 1894 struct trace_event_file *file); 1895 void (*unreg_all)(struct trace_event_file *file); 1896 int (*set_filter)(char *filter_str, 1897 struct event_trigger_data *data, 1898 struct trace_event_file *file); 1899 struct event_trigger_ops *(*get_trigger_ops)(char *cmd, char *param); 1900 }; 1901 1902 /** 1903 * enum event_command_flags - flags for struct event_command 1904 * 1905 * @POST_TRIGGER: A flag that says whether or not this command needs 1906 * to have its action delayed until after the current event has 1907 * been closed. Some triggers need to avoid being invoked while 1908 * an event is currently in the process of being logged, since 1909 * the trigger may itself log data into the trace buffer. Thus 1910 * we make sure the current event is committed before invoking 1911 * those triggers. To do that, the trigger invocation is split 1912 * in two - the first part checks the filter using the current 1913 * trace record; if a command has the @post_trigger flag set, it 1914 * sets a bit for itself in the return value, otherwise it 1915 * directly invokes the trigger. Once all commands have been 1916 * either invoked or set their return flag, the current record is 1917 * either committed or discarded. At that point, if any commands 1918 * have deferred their triggers, those commands are finally 1919 * invoked following the close of the current event. In other 1920 * words, if the event_trigger_ops @func() probe implementation 1921 * itself logs to the trace buffer, this flag should be set, 1922 * otherwise it can be left unspecified. 1923 * 1924 * @NEEDS_REC: A flag that says whether or not this command needs 1925 * access to the trace record in order to perform its function, 1926 * regardless of whether or not it has a filter associated with 1927 * it (filters make a trigger require access to the trace record 1928 * but are not always present). 1929 */ 1930 enum event_command_flags { 1931 EVENT_CMD_FL_POST_TRIGGER = 1, 1932 EVENT_CMD_FL_NEEDS_REC = 2, 1933 }; 1934 1935 static inline bool event_command_post_trigger(struct event_command *cmd_ops) 1936 { 1937 return cmd_ops->flags & EVENT_CMD_FL_POST_TRIGGER; 1938 } 1939 1940 static inline bool event_command_needs_rec(struct event_command *cmd_ops) 1941 { 1942 return cmd_ops->flags & EVENT_CMD_FL_NEEDS_REC; 1943 } 1944 1945 extern int trace_event_enable_disable(struct trace_event_file *file, 1946 int enable, int soft_disable); 1947 extern int tracing_alloc_snapshot(void); 1948 extern void tracing_snapshot_cond(struct trace_array *tr, void *cond_data); 1949 extern int tracing_snapshot_cond_enable(struct trace_array *tr, void *cond_data, cond_update_fn_t update); 1950 1951 extern int tracing_snapshot_cond_disable(struct trace_array *tr); 1952 extern void *tracing_cond_snapshot_data(struct trace_array *tr); 1953 1954 extern const char *__start___trace_bprintk_fmt[]; 1955 extern const char *__stop___trace_bprintk_fmt[]; 1956 1957 extern const char *__start___tracepoint_str[]; 1958 extern const char *__stop___tracepoint_str[]; 1959 1960 void trace_printk_control(bool enabled); 1961 void trace_printk_start_comm(void); 1962 int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set); 1963 int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled); 1964 1965 /* Used from boot time tracer */ 1966 extern int trace_set_options(struct trace_array *tr, char *option); 1967 extern int tracing_set_tracer(struct trace_array *tr, const char *buf); 1968 extern ssize_t tracing_resize_ring_buffer(struct trace_array *tr, 1969 unsigned long size, int cpu_id); 1970 extern int tracing_set_cpumask(struct trace_array *tr, 1971 cpumask_var_t tracing_cpumask_new); 1972 1973 1974 #define MAX_EVENT_NAME_LEN 64 1975 1976 extern int trace_run_command(const char *buf, int (*createfn)(int, char**)); 1977 extern ssize_t trace_parse_run_command(struct file *file, 1978 const char __user *buffer, size_t count, loff_t *ppos, 1979 int (*createfn)(int, char**)); 1980 1981 extern unsigned int err_pos(char *cmd, const char *str); 1982 extern void tracing_log_err(struct trace_array *tr, 1983 const char *loc, const char *cmd, 1984 const char **errs, u8 type, u8 pos); 1985 1986 /* 1987 * Normal trace_printk() and friends allocates special buffers 1988 * to do the manipulation, as well as saves the print formats 1989 * into sections to display. But the trace infrastructure wants 1990 * to use these without the added overhead at the price of being 1991 * a bit slower (used mainly for warnings, where we don't care 1992 * about performance). The internal_trace_puts() is for such 1993 * a purpose. 1994 */ 1995 #define internal_trace_puts(str) __trace_puts(_THIS_IP_, str, strlen(str)) 1996 1997 #undef FTRACE_ENTRY 1998 #define FTRACE_ENTRY(call, struct_name, id, tstruct, print) \ 1999 extern struct trace_event_call \ 2000 __aligned(4) event_##call; 2001 #undef FTRACE_ENTRY_DUP 2002 #define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print) \ 2003 FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print)) 2004 #undef FTRACE_ENTRY_PACKED 2005 #define FTRACE_ENTRY_PACKED(call, struct_name, id, tstruct, print) \ 2006 FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print)) 2007 2008 #include "trace_entries.h" 2009 2010 #if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER) 2011 int perf_ftrace_event_register(struct trace_event_call *call, 2012 enum trace_reg type, void *data); 2013 #else 2014 #define perf_ftrace_event_register NULL 2015 #endif 2016 2017 #ifdef CONFIG_FTRACE_SYSCALLS 2018 void init_ftrace_syscalls(void); 2019 const char *get_syscall_name(int syscall); 2020 #else 2021 static inline void init_ftrace_syscalls(void) { } 2022 static inline const char *get_syscall_name(int syscall) 2023 { 2024 return NULL; 2025 } 2026 #endif 2027 2028 #ifdef CONFIG_EVENT_TRACING 2029 void trace_event_init(void); 2030 void trace_event_eval_update(struct trace_eval_map **map, int len); 2031 /* Used from boot time tracer */ 2032 extern int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set); 2033 extern int trigger_process_regex(struct trace_event_file *file, char *buff); 2034 #else 2035 static inline void __init trace_event_init(void) { } 2036 static inline void trace_event_eval_update(struct trace_eval_map **map, int len) { } 2037 #endif 2038 2039 #ifdef CONFIG_TRACER_SNAPSHOT 2040 void tracing_snapshot_instance(struct trace_array *tr); 2041 int tracing_alloc_snapshot_instance(struct trace_array *tr); 2042 #else 2043 static inline void tracing_snapshot_instance(struct trace_array *tr) { } 2044 static inline int tracing_alloc_snapshot_instance(struct trace_array *tr) 2045 { 2046 return 0; 2047 } 2048 #endif 2049 2050 #ifdef CONFIG_PREEMPT_TRACER 2051 void tracer_preempt_on(unsigned long a0, unsigned long a1); 2052 void tracer_preempt_off(unsigned long a0, unsigned long a1); 2053 #else 2054 static inline void tracer_preempt_on(unsigned long a0, unsigned long a1) { } 2055 static inline void tracer_preempt_off(unsigned long a0, unsigned long a1) { } 2056 #endif 2057 #ifdef CONFIG_IRQSOFF_TRACER 2058 void tracer_hardirqs_on(unsigned long a0, unsigned long a1); 2059 void tracer_hardirqs_off(unsigned long a0, unsigned long a1); 2060 #else 2061 static inline void tracer_hardirqs_on(unsigned long a0, unsigned long a1) { } 2062 static inline void tracer_hardirqs_off(unsigned long a0, unsigned long a1) { } 2063 #endif 2064 2065 extern struct trace_iterator *tracepoint_print_iter; 2066 2067 /* 2068 * Reset the state of the trace_iterator so that it can read consumed data. 2069 * Normally, the trace_iterator is used for reading the data when it is not 2070 * consumed, and must retain state. 2071 */ 2072 static __always_inline void trace_iterator_reset(struct trace_iterator *iter) 2073 { 2074 const size_t offset = offsetof(struct trace_iterator, seq); 2075 2076 /* 2077 * Keep gcc from complaining about overwriting more than just one 2078 * member in the structure. 2079 */ 2080 memset((char *)iter + offset, 0, sizeof(struct trace_iterator) - offset); 2081 2082 iter->pos = -1; 2083 } 2084 2085 #endif /* _LINUX_KERNEL_TRACE_H */ 2086