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 24 #ifdef CONFIG_FTRACE_SYSCALLS 25 #include <asm/unistd.h> /* For NR_SYSCALLS */ 26 #include <asm/syscall.h> /* some archs define it here */ 27 #endif 28 29 enum trace_type { 30 __TRACE_FIRST_TYPE = 0, 31 32 TRACE_FN, 33 TRACE_CTX, 34 TRACE_WAKE, 35 TRACE_STACK, 36 TRACE_PRINT, 37 TRACE_BPRINT, 38 TRACE_MMIO_RW, 39 TRACE_MMIO_MAP, 40 TRACE_BRANCH, 41 TRACE_GRAPH_RET, 42 TRACE_GRAPH_ENT, 43 TRACE_USER_STACK, 44 TRACE_BLK, 45 TRACE_BPUTS, 46 TRACE_HWLAT, 47 TRACE_RAW_DATA, 48 49 __TRACE_LAST_TYPE, 50 }; 51 52 53 #undef __field 54 #define __field(type, item) type item; 55 56 #undef __field_fn 57 #define __field_fn(type, item) type item; 58 59 #undef __field_struct 60 #define __field_struct(type, item) __field(type, item) 61 62 #undef __field_desc 63 #define __field_desc(type, container, item) 64 65 #undef __field_packed 66 #define __field_packed(type, container, item) 67 68 #undef __array 69 #define __array(type, item, size) type item[size]; 70 71 #undef __array_desc 72 #define __array_desc(type, container, item, size) 73 74 #undef __dynamic_array 75 #define __dynamic_array(type, item) type item[]; 76 77 #undef F_STRUCT 78 #define F_STRUCT(args...) args 79 80 #undef FTRACE_ENTRY 81 #define FTRACE_ENTRY(name, struct_name, id, tstruct, print) \ 82 struct struct_name { \ 83 struct trace_entry ent; \ 84 tstruct \ 85 } 86 87 #undef FTRACE_ENTRY_DUP 88 #define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk) 89 90 #undef FTRACE_ENTRY_REG 91 #define FTRACE_ENTRY_REG(name, struct_name, id, tstruct, print, regfn) \ 92 FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print)) 93 94 #undef FTRACE_ENTRY_PACKED 95 #define FTRACE_ENTRY_PACKED(name, struct_name, id, tstruct, print) \ 96 FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print)) __packed 97 98 #include "trace_entries.h" 99 100 /* Use this for memory failure errors */ 101 #define MEM_FAIL(condition, fmt, ...) ({ \ 102 static bool __section(".data.once") __warned; \ 103 int __ret_warn_once = !!(condition); \ 104 \ 105 if (unlikely(__ret_warn_once && !__warned)) { \ 106 __warned = true; \ 107 pr_err("ERROR: " fmt, ##__VA_ARGS__); \ 108 } \ 109 unlikely(__ret_warn_once); \ 110 }) 111 112 /* 113 * syscalls are special, and need special handling, this is why 114 * they are not included in trace_entries.h 115 */ 116 struct syscall_trace_enter { 117 struct trace_entry ent; 118 int nr; 119 unsigned long args[]; 120 }; 121 122 struct syscall_trace_exit { 123 struct trace_entry ent; 124 int nr; 125 long ret; 126 }; 127 128 struct kprobe_trace_entry_head { 129 struct trace_entry ent; 130 unsigned long ip; 131 }; 132 133 struct kretprobe_trace_entry_head { 134 struct trace_entry ent; 135 unsigned long func; 136 unsigned long ret_ip; 137 }; 138 139 /* 140 * trace_flag_type is an enumeration that holds different 141 * states when a trace occurs. These are: 142 * IRQS_OFF - interrupts were disabled 143 * IRQS_NOSUPPORT - arch does not support irqs_disabled_flags 144 * NEED_RESCHED - reschedule is requested 145 * HARDIRQ - inside an interrupt handler 146 * SOFTIRQ - inside a softirq handler 147 */ 148 enum trace_flag_type { 149 TRACE_FLAG_IRQS_OFF = 0x01, 150 TRACE_FLAG_IRQS_NOSUPPORT = 0x02, 151 TRACE_FLAG_NEED_RESCHED = 0x04, 152 TRACE_FLAG_HARDIRQ = 0x08, 153 TRACE_FLAG_SOFTIRQ = 0x10, 154 TRACE_FLAG_PREEMPT_RESCHED = 0x20, 155 TRACE_FLAG_NMI = 0x40, 156 }; 157 158 #define TRACE_BUF_SIZE 1024 159 160 struct trace_array; 161 162 /* 163 * The CPU trace array - it consists of thousands of trace entries 164 * plus some other descriptor data: (for example which task started 165 * the trace, etc.) 166 */ 167 struct trace_array_cpu { 168 atomic_t disabled; 169 void *buffer_page; /* ring buffer spare */ 170 171 unsigned long entries; 172 unsigned long saved_latency; 173 unsigned long critical_start; 174 unsigned long critical_end; 175 unsigned long critical_sequence; 176 unsigned long nice; 177 unsigned long policy; 178 unsigned long rt_priority; 179 unsigned long skipped_entries; 180 u64 preempt_timestamp; 181 pid_t pid; 182 kuid_t uid; 183 char comm[TASK_COMM_LEN]; 184 185 #ifdef CONFIG_FUNCTION_TRACER 186 int ftrace_ignore_pid; 187 #endif 188 bool ignore_pid; 189 }; 190 191 struct tracer; 192 struct trace_option_dentry; 193 194 struct array_buffer { 195 struct trace_array *tr; 196 struct trace_buffer *buffer; 197 struct trace_array_cpu __percpu *data; 198 u64 time_start; 199 int cpu; 200 }; 201 202 #define TRACE_FLAGS_MAX_SIZE 32 203 204 struct trace_options { 205 struct tracer *tracer; 206 struct trace_option_dentry *topts; 207 }; 208 209 struct trace_pid_list { 210 int pid_max; 211 unsigned long *pids; 212 }; 213 214 enum { 215 TRACE_PIDS = BIT(0), 216 TRACE_NO_PIDS = BIT(1), 217 }; 218 219 static inline bool pid_type_enabled(int type, struct trace_pid_list *pid_list, 220 struct trace_pid_list *no_pid_list) 221 { 222 /* Return true if the pid list in type has pids */ 223 return ((type & TRACE_PIDS) && pid_list) || 224 ((type & TRACE_NO_PIDS) && no_pid_list); 225 } 226 227 static inline bool still_need_pid_events(int type, struct trace_pid_list *pid_list, 228 struct trace_pid_list *no_pid_list) 229 { 230 /* 231 * Turning off what is in @type, return true if the "other" 232 * pid list, still has pids in it. 233 */ 234 return (!(type & TRACE_PIDS) && pid_list) || 235 (!(type & TRACE_NO_PIDS) && no_pid_list); 236 } 237 238 typedef bool (*cond_update_fn_t)(struct trace_array *tr, void *cond_data); 239 240 /** 241 * struct cond_snapshot - conditional snapshot data and callback 242 * 243 * The cond_snapshot structure encapsulates a callback function and 244 * data associated with the snapshot for a given tracing instance. 245 * 246 * When a snapshot is taken conditionally, by invoking 247 * tracing_snapshot_cond(tr, cond_data), the cond_data passed in is 248 * passed in turn to the cond_snapshot.update() function. That data 249 * can be compared by the update() implementation with the cond_data 250 * contained within the struct cond_snapshot instance associated with 251 * the trace_array. Because the tr->max_lock is held throughout the 252 * update() call, the update() function can directly retrieve the 253 * cond_snapshot and cond_data associated with the per-instance 254 * snapshot associated with the trace_array. 255 * 256 * The cond_snapshot.update() implementation can save data to be 257 * associated with the snapshot if it decides to, and returns 'true' 258 * in that case, or it returns 'false' if the conditional snapshot 259 * shouldn't be taken. 260 * 261 * The cond_snapshot instance is created and associated with the 262 * user-defined cond_data by tracing_cond_snapshot_enable(). 263 * Likewise, the cond_snapshot instance is destroyed and is no longer 264 * associated with the trace instance by 265 * tracing_cond_snapshot_disable(). 266 * 267 * The method below is required. 268 * 269 * @update: When a conditional snapshot is invoked, the update() 270 * callback function is invoked with the tr->max_lock held. The 271 * update() implementation signals whether or not to actually 272 * take the snapshot, by returning 'true' if so, 'false' if no 273 * snapshot should be taken. Because the max_lock is held for 274 * the duration of update(), the implementation is safe to 275 * directly retrieved and save any implementation data it needs 276 * to in association with the snapshot. 277 */ 278 struct cond_snapshot { 279 void *cond_data; 280 cond_update_fn_t update; 281 }; 282 283 /* 284 * The trace array - an array of per-CPU trace arrays. This is the 285 * highest level data structure that individual tracers deal with. 286 * They have on/off state as well: 287 */ 288 struct trace_array { 289 struct list_head list; 290 char *name; 291 struct array_buffer array_buffer; 292 #ifdef CONFIG_TRACER_MAX_TRACE 293 /* 294 * The max_buffer is used to snapshot the trace when a maximum 295 * latency is reached, or when the user initiates a snapshot. 296 * Some tracers will use this to store a maximum trace while 297 * it continues examining live traces. 298 * 299 * The buffers for the max_buffer are set up the same as the array_buffer 300 * When a snapshot is taken, the buffer of the max_buffer is swapped 301 * with the buffer of the array_buffer and the buffers are reset for 302 * the array_buffer so the tracing can continue. 303 */ 304 struct array_buffer max_buffer; 305 bool allocated_snapshot; 306 #endif 307 #if defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER) 308 unsigned long max_latency; 309 #ifdef CONFIG_FSNOTIFY 310 struct dentry *d_max_latency; 311 struct work_struct fsnotify_work; 312 struct irq_work fsnotify_irqwork; 313 #endif 314 #endif 315 struct trace_pid_list __rcu *filtered_pids; 316 struct trace_pid_list __rcu *filtered_no_pids; 317 /* 318 * max_lock is used to protect the swapping of buffers 319 * when taking a max snapshot. The buffers themselves are 320 * protected by per_cpu spinlocks. But the action of the swap 321 * needs its own lock. 322 * 323 * This is defined as a arch_spinlock_t in order to help 324 * with performance when lockdep debugging is enabled. 325 * 326 * It is also used in other places outside the update_max_tr 327 * so it needs to be defined outside of the 328 * CONFIG_TRACER_MAX_TRACE. 329 */ 330 arch_spinlock_t max_lock; 331 int buffer_disabled; 332 #ifdef CONFIG_FTRACE_SYSCALLS 333 int sys_refcount_enter; 334 int sys_refcount_exit; 335 struct trace_event_file __rcu *enter_syscall_files[NR_syscalls]; 336 struct trace_event_file __rcu *exit_syscall_files[NR_syscalls]; 337 #endif 338 int stop_count; 339 int clock_id; 340 int nr_topts; 341 bool clear_trace; 342 int buffer_percent; 343 unsigned int n_err_log_entries; 344 struct tracer *current_trace; 345 unsigned int trace_flags; 346 unsigned char trace_flags_index[TRACE_FLAGS_MAX_SIZE]; 347 unsigned int flags; 348 raw_spinlock_t start_lock; 349 struct list_head err_log; 350 struct dentry *dir; 351 struct dentry *options; 352 struct dentry *percpu_dir; 353 struct dentry *event_dir; 354 struct trace_options *topts; 355 struct list_head systems; 356 struct list_head events; 357 struct trace_event_file *trace_marker_file; 358 cpumask_var_t tracing_cpumask; /* only trace on set CPUs */ 359 int ref; 360 int trace_ref; 361 #ifdef CONFIG_FUNCTION_TRACER 362 struct ftrace_ops *ops; 363 struct trace_pid_list __rcu *function_pids; 364 struct trace_pid_list __rcu *function_no_pids; 365 #ifdef CONFIG_DYNAMIC_FTRACE 366 /* All of these are protected by the ftrace_lock */ 367 struct list_head func_probes; 368 struct list_head mod_trace; 369 struct list_head mod_notrace; 370 #endif 371 /* function tracing enabled */ 372 int function_enabled; 373 #endif 374 int time_stamp_abs_ref; 375 struct list_head hist_vars; 376 #ifdef CONFIG_TRACER_SNAPSHOT 377 struct cond_snapshot *cond_snapshot; 378 #endif 379 }; 380 381 enum { 382 TRACE_ARRAY_FL_GLOBAL = (1 << 0) 383 }; 384 385 extern struct list_head ftrace_trace_arrays; 386 387 extern struct mutex trace_types_lock; 388 389 extern int trace_array_get(struct trace_array *tr); 390 extern int tracing_check_open_get_tr(struct trace_array *tr); 391 extern struct trace_array *trace_array_find(const char *instance); 392 extern struct trace_array *trace_array_find_get(const char *instance); 393 394 extern int tracing_set_time_stamp_abs(struct trace_array *tr, bool abs); 395 extern int tracing_set_clock(struct trace_array *tr, const char *clockstr); 396 397 extern bool trace_clock_in_ns(struct trace_array *tr); 398 399 /* 400 * The global tracer (top) should be the first trace array added, 401 * but we check the flag anyway. 402 */ 403 static inline struct trace_array *top_trace_array(void) 404 { 405 struct trace_array *tr; 406 407 if (list_empty(&ftrace_trace_arrays)) 408 return NULL; 409 410 tr = list_entry(ftrace_trace_arrays.prev, 411 typeof(*tr), list); 412 WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL)); 413 return tr; 414 } 415 416 #define FTRACE_CMP_TYPE(var, type) \ 417 __builtin_types_compatible_p(typeof(var), type *) 418 419 #undef IF_ASSIGN 420 #define IF_ASSIGN(var, entry, etype, id) \ 421 if (FTRACE_CMP_TYPE(var, etype)) { \ 422 var = (typeof(var))(entry); \ 423 WARN_ON(id != 0 && (entry)->type != id); \ 424 break; \ 425 } 426 427 /* Will cause compile errors if type is not found. */ 428 extern void __ftrace_bad_type(void); 429 430 /* 431 * The trace_assign_type is a verifier that the entry type is 432 * the same as the type being assigned. To add new types simply 433 * add a line with the following format: 434 * 435 * IF_ASSIGN(var, ent, type, id); 436 * 437 * Where "type" is the trace type that includes the trace_entry 438 * as the "ent" item. And "id" is the trace identifier that is 439 * used in the trace_type enum. 440 * 441 * If the type can have more than one id, then use zero. 442 */ 443 #define trace_assign_type(var, ent) \ 444 do { \ 445 IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN); \ 446 IF_ASSIGN(var, ent, struct ctx_switch_entry, 0); \ 447 IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK); \ 448 IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\ 449 IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT); \ 450 IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT); \ 451 IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS); \ 452 IF_ASSIGN(var, ent, struct hwlat_entry, TRACE_HWLAT); \ 453 IF_ASSIGN(var, ent, struct raw_data_entry, TRACE_RAW_DATA);\ 454 IF_ASSIGN(var, ent, struct trace_mmiotrace_rw, \ 455 TRACE_MMIO_RW); \ 456 IF_ASSIGN(var, ent, struct trace_mmiotrace_map, \ 457 TRACE_MMIO_MAP); \ 458 IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \ 459 IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry, \ 460 TRACE_GRAPH_ENT); \ 461 IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry, \ 462 TRACE_GRAPH_RET); \ 463 __ftrace_bad_type(); \ 464 } while (0) 465 466 /* 467 * An option specific to a tracer. This is a boolean value. 468 * The bit is the bit index that sets its value on the 469 * flags value in struct tracer_flags. 470 */ 471 struct tracer_opt { 472 const char *name; /* Will appear on the trace_options file */ 473 u32 bit; /* Mask assigned in val field in tracer_flags */ 474 }; 475 476 /* 477 * The set of specific options for a tracer. Your tracer 478 * have to set the initial value of the flags val. 479 */ 480 struct tracer_flags { 481 u32 val; 482 struct tracer_opt *opts; 483 struct tracer *trace; 484 }; 485 486 /* Makes more easy to define a tracer opt */ 487 #define TRACER_OPT(s, b) .name = #s, .bit = b 488 489 490 struct trace_option_dentry { 491 struct tracer_opt *opt; 492 struct tracer_flags *flags; 493 struct trace_array *tr; 494 struct dentry *entry; 495 }; 496 497 /** 498 * struct tracer - a specific tracer and its callbacks to interact with tracefs 499 * @name: the name chosen to select it on the available_tracers file 500 * @init: called when one switches to this tracer (echo name > current_tracer) 501 * @reset: called when one switches to another tracer 502 * @start: called when tracing is unpaused (echo 1 > tracing_on) 503 * @stop: called when tracing is paused (echo 0 > tracing_on) 504 * @update_thresh: called when tracing_thresh is updated 505 * @open: called when the trace file is opened 506 * @pipe_open: called when the trace_pipe file is opened 507 * @close: called when the trace file is released 508 * @pipe_close: called when the trace_pipe file is released 509 * @read: override the default read callback on trace_pipe 510 * @splice_read: override the default splice_read callback on trace_pipe 511 * @selftest: selftest to run on boot (see trace_selftest.c) 512 * @print_headers: override the first lines that describe your columns 513 * @print_line: callback that prints a trace 514 * @set_flag: signals one of your private flags changed (trace_options file) 515 * @flags: your private flags 516 */ 517 struct tracer { 518 const char *name; 519 int (*init)(struct trace_array *tr); 520 void (*reset)(struct trace_array *tr); 521 void (*start)(struct trace_array *tr); 522 void (*stop)(struct trace_array *tr); 523 int (*update_thresh)(struct trace_array *tr); 524 void (*open)(struct trace_iterator *iter); 525 void (*pipe_open)(struct trace_iterator *iter); 526 void (*close)(struct trace_iterator *iter); 527 void (*pipe_close)(struct trace_iterator *iter); 528 ssize_t (*read)(struct trace_iterator *iter, 529 struct file *filp, char __user *ubuf, 530 size_t cnt, loff_t *ppos); 531 ssize_t (*splice_read)(struct trace_iterator *iter, 532 struct file *filp, 533 loff_t *ppos, 534 struct pipe_inode_info *pipe, 535 size_t len, 536 unsigned int flags); 537 #ifdef CONFIG_FTRACE_STARTUP_TEST 538 int (*selftest)(struct tracer *trace, 539 struct trace_array *tr); 540 #endif 541 void (*print_header)(struct seq_file *m); 542 enum print_line_t (*print_line)(struct trace_iterator *iter); 543 /* If you handled the flag setting, return 0 */ 544 int (*set_flag)(struct trace_array *tr, 545 u32 old_flags, u32 bit, int set); 546 /* Return 0 if OK with change, else return non-zero */ 547 int (*flag_changed)(struct trace_array *tr, 548 u32 mask, int set); 549 struct tracer *next; 550 struct tracer_flags *flags; 551 int enabled; 552 bool print_max; 553 bool allow_instances; 554 #ifdef CONFIG_TRACER_MAX_TRACE 555 bool use_max_tr; 556 #endif 557 /* True if tracer cannot be enabled in kernel param */ 558 bool noboot; 559 }; 560 561 562 /* Only current can touch trace_recursion */ 563 564 /* 565 * For function tracing recursion: 566 * The order of these bits are important. 567 * 568 * When function tracing occurs, the following steps are made: 569 * If arch does not support a ftrace feature: 570 * call internal function (uses INTERNAL bits) which calls... 571 * If callback is registered to the "global" list, the list 572 * function is called and recursion checks the GLOBAL bits. 573 * then this function calls... 574 * The function callback, which can use the FTRACE bits to 575 * check for recursion. 576 * 577 * Now if the arch does not support a feature, and it calls 578 * the global list function which calls the ftrace callback 579 * all three of these steps will do a recursion protection. 580 * There's no reason to do one if the previous caller already 581 * did. The recursion that we are protecting against will 582 * go through the same steps again. 583 * 584 * To prevent the multiple recursion checks, if a recursion 585 * bit is set that is higher than the MAX bit of the current 586 * check, then we know that the check was made by the previous 587 * caller, and we can skip the current check. 588 */ 589 enum { 590 /* Function recursion bits */ 591 TRACE_FTRACE_BIT, 592 TRACE_FTRACE_NMI_BIT, 593 TRACE_FTRACE_IRQ_BIT, 594 TRACE_FTRACE_SIRQ_BIT, 595 596 /* INTERNAL_BITs must be greater than FTRACE_BITs */ 597 TRACE_INTERNAL_BIT, 598 TRACE_INTERNAL_NMI_BIT, 599 TRACE_INTERNAL_IRQ_BIT, 600 TRACE_INTERNAL_SIRQ_BIT, 601 602 TRACE_BRANCH_BIT, 603 /* 604 * Abuse of the trace_recursion. 605 * As we need a way to maintain state if we are tracing the function 606 * graph in irq because we want to trace a particular function that 607 * was called in irq context but we have irq tracing off. Since this 608 * can only be modified by current, we can reuse trace_recursion. 609 */ 610 TRACE_IRQ_BIT, 611 612 /* Set if the function is in the set_graph_function file */ 613 TRACE_GRAPH_BIT, 614 615 /* 616 * In the very unlikely case that an interrupt came in 617 * at a start of graph tracing, and we want to trace 618 * the function in that interrupt, the depth can be greater 619 * than zero, because of the preempted start of a previous 620 * trace. In an even more unlikely case, depth could be 2 621 * if a softirq interrupted the start of graph tracing, 622 * followed by an interrupt preempting a start of graph 623 * tracing in the softirq, and depth can even be 3 624 * if an NMI came in at the start of an interrupt function 625 * that preempted a softirq start of a function that 626 * preempted normal context!!!! Luckily, it can't be 627 * greater than 3, so the next two bits are a mask 628 * of what the depth is when we set TRACE_GRAPH_BIT 629 */ 630 631 TRACE_GRAPH_DEPTH_START_BIT, 632 TRACE_GRAPH_DEPTH_END_BIT, 633 634 /* 635 * To implement set_graph_notrace, if this bit is set, we ignore 636 * function graph tracing of called functions, until the return 637 * function is called to clear it. 638 */ 639 TRACE_GRAPH_NOTRACE_BIT, 640 641 /* 642 * When transitioning between context, the preempt_count() may 643 * not be correct. Allow for a single recursion to cover this case. 644 */ 645 TRACE_TRANSITION_BIT, 646 }; 647 648 #define trace_recursion_set(bit) do { (current)->trace_recursion |= (1<<(bit)); } while (0) 649 #define trace_recursion_clear(bit) do { (current)->trace_recursion &= ~(1<<(bit)); } while (0) 650 #define trace_recursion_test(bit) ((current)->trace_recursion & (1<<(bit))) 651 652 #define trace_recursion_depth() \ 653 (((current)->trace_recursion >> TRACE_GRAPH_DEPTH_START_BIT) & 3) 654 #define trace_recursion_set_depth(depth) \ 655 do { \ 656 current->trace_recursion &= \ 657 ~(3 << TRACE_GRAPH_DEPTH_START_BIT); \ 658 current->trace_recursion |= \ 659 ((depth) & 3) << TRACE_GRAPH_DEPTH_START_BIT; \ 660 } while (0) 661 662 #define TRACE_CONTEXT_BITS 4 663 664 #define TRACE_FTRACE_START TRACE_FTRACE_BIT 665 #define TRACE_FTRACE_MAX ((1 << (TRACE_FTRACE_START + TRACE_CONTEXT_BITS)) - 1) 666 667 #define TRACE_LIST_START TRACE_INTERNAL_BIT 668 #define TRACE_LIST_MAX ((1 << (TRACE_LIST_START + TRACE_CONTEXT_BITS)) - 1) 669 670 #define TRACE_CONTEXT_MASK TRACE_LIST_MAX 671 672 static __always_inline int trace_get_context_bit(void) 673 { 674 int bit; 675 676 if (in_interrupt()) { 677 if (in_nmi()) 678 bit = 0; 679 680 else if (in_irq()) 681 bit = 1; 682 else 683 bit = 2; 684 } else 685 bit = 3; 686 687 return bit; 688 } 689 690 static __always_inline int trace_test_and_set_recursion(int start, int max) 691 { 692 unsigned int val = current->trace_recursion; 693 int bit; 694 695 /* A previous recursion check was made */ 696 if ((val & TRACE_CONTEXT_MASK) > max) 697 return 0; 698 699 bit = trace_get_context_bit() + start; 700 if (unlikely(val & (1 << bit))) { 701 /* 702 * It could be that preempt_count has not been updated during 703 * a switch between contexts. Allow for a single recursion. 704 */ 705 bit = TRACE_TRANSITION_BIT; 706 if (trace_recursion_test(bit)) 707 return -1; 708 trace_recursion_set(bit); 709 barrier(); 710 return bit + 1; 711 } 712 713 /* Normal check passed, clear the transition to allow it again */ 714 trace_recursion_clear(TRACE_TRANSITION_BIT); 715 716 val |= 1 << bit; 717 current->trace_recursion = val; 718 barrier(); 719 720 return bit + 1; 721 } 722 723 static __always_inline void trace_clear_recursion(int bit) 724 { 725 unsigned int val = current->trace_recursion; 726 727 if (!bit) 728 return; 729 730 bit--; 731 bit = 1 << bit; 732 val &= ~bit; 733 734 barrier(); 735 current->trace_recursion = val; 736 } 737 738 static inline struct ring_buffer_iter * 739 trace_buffer_iter(struct trace_iterator *iter, int cpu) 740 { 741 return iter->buffer_iter ? iter->buffer_iter[cpu] : NULL; 742 } 743 744 int tracer_init(struct tracer *t, struct trace_array *tr); 745 int tracing_is_enabled(void); 746 void tracing_reset_online_cpus(struct array_buffer *buf); 747 void tracing_reset_current(int cpu); 748 void tracing_reset_all_online_cpus(void); 749 int tracing_open_generic(struct inode *inode, struct file *filp); 750 int tracing_open_generic_tr(struct inode *inode, struct file *filp); 751 bool tracing_is_disabled(void); 752 bool tracer_tracing_is_on(struct trace_array *tr); 753 void tracer_tracing_on(struct trace_array *tr); 754 void tracer_tracing_off(struct trace_array *tr); 755 struct dentry *trace_create_file(const char *name, 756 umode_t mode, 757 struct dentry *parent, 758 void *data, 759 const struct file_operations *fops); 760 761 int tracing_init_dentry(void); 762 763 struct ring_buffer_event; 764 765 struct ring_buffer_event * 766 trace_buffer_lock_reserve(struct trace_buffer *buffer, 767 int type, 768 unsigned long len, 769 unsigned long flags, 770 int pc); 771 772 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr, 773 struct trace_array_cpu *data); 774 775 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, 776 int *ent_cpu, u64 *ent_ts); 777 778 void trace_buffer_unlock_commit_nostack(struct trace_buffer *buffer, 779 struct ring_buffer_event *event); 780 781 int trace_empty(struct trace_iterator *iter); 782 783 void *trace_find_next_entry_inc(struct trace_iterator *iter); 784 785 void trace_init_global_iter(struct trace_iterator *iter); 786 787 void tracing_iter_reset(struct trace_iterator *iter, int cpu); 788 789 unsigned long trace_total_entries_cpu(struct trace_array *tr, int cpu); 790 unsigned long trace_total_entries(struct trace_array *tr); 791 792 void trace_function(struct trace_array *tr, 793 unsigned long ip, 794 unsigned long parent_ip, 795 unsigned long flags, int pc); 796 void trace_graph_function(struct trace_array *tr, 797 unsigned long ip, 798 unsigned long parent_ip, 799 unsigned long flags, int pc); 800 void trace_latency_header(struct seq_file *m); 801 void trace_default_header(struct seq_file *m); 802 void print_trace_header(struct seq_file *m, struct trace_iterator *iter); 803 int trace_empty(struct trace_iterator *iter); 804 805 void trace_graph_return(struct ftrace_graph_ret *trace); 806 int trace_graph_entry(struct ftrace_graph_ent *trace); 807 void set_graph_array(struct trace_array *tr); 808 809 void tracing_start_cmdline_record(void); 810 void tracing_stop_cmdline_record(void); 811 void tracing_start_tgid_record(void); 812 void tracing_stop_tgid_record(void); 813 814 int register_tracer(struct tracer *type); 815 int is_tracing_stopped(void); 816 817 loff_t tracing_lseek(struct file *file, loff_t offset, int whence); 818 819 extern cpumask_var_t __read_mostly tracing_buffer_mask; 820 821 #define for_each_tracing_cpu(cpu) \ 822 for_each_cpu(cpu, tracing_buffer_mask) 823 824 extern unsigned long nsecs_to_usecs(unsigned long nsecs); 825 826 extern unsigned long tracing_thresh; 827 828 /* PID filtering */ 829 830 extern int pid_max; 831 832 bool trace_find_filtered_pid(struct trace_pid_list *filtered_pids, 833 pid_t search_pid); 834 bool trace_ignore_this_task(struct trace_pid_list *filtered_pids, 835 struct trace_pid_list *filtered_no_pids, 836 struct task_struct *task); 837 void trace_filter_add_remove_task(struct trace_pid_list *pid_list, 838 struct task_struct *self, 839 struct task_struct *task); 840 void *trace_pid_next(struct trace_pid_list *pid_list, void *v, loff_t *pos); 841 void *trace_pid_start(struct trace_pid_list *pid_list, loff_t *pos); 842 int trace_pid_show(struct seq_file *m, void *v); 843 void trace_free_pid_list(struct trace_pid_list *pid_list); 844 int trace_pid_write(struct trace_pid_list *filtered_pids, 845 struct trace_pid_list **new_pid_list, 846 const char __user *ubuf, size_t cnt); 847 848 #ifdef CONFIG_TRACER_MAX_TRACE 849 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu, 850 void *cond_data); 851 void update_max_tr_single(struct trace_array *tr, 852 struct task_struct *tsk, int cpu); 853 #endif /* CONFIG_TRACER_MAX_TRACE */ 854 855 #if (defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER)) && \ 856 defined(CONFIG_FSNOTIFY) 857 858 void latency_fsnotify(struct trace_array *tr); 859 860 #else 861 862 static inline void latency_fsnotify(struct trace_array *tr) { } 863 864 #endif 865 866 #ifdef CONFIG_STACKTRACE 867 void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, 868 int pc); 869 #else 870 static inline void __trace_stack(struct trace_array *tr, unsigned long flags, 871 int skip, int pc) 872 { 873 } 874 #endif /* CONFIG_STACKTRACE */ 875 876 extern u64 ftrace_now(int cpu); 877 878 extern void trace_find_cmdline(int pid, char comm[]); 879 extern int trace_find_tgid(int pid); 880 extern void trace_event_follow_fork(struct trace_array *tr, bool enable); 881 882 #ifdef CONFIG_DYNAMIC_FTRACE 883 extern unsigned long ftrace_update_tot_cnt; 884 extern unsigned long ftrace_number_of_pages; 885 extern unsigned long ftrace_number_of_groups; 886 void ftrace_init_trace_array(struct trace_array *tr); 887 #else 888 static inline void ftrace_init_trace_array(struct trace_array *tr) { } 889 #endif 890 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func 891 extern int DYN_FTRACE_TEST_NAME(void); 892 #define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2 893 extern int DYN_FTRACE_TEST_NAME2(void); 894 895 extern bool ring_buffer_expanded; 896 extern bool tracing_selftest_disabled; 897 898 #ifdef CONFIG_FTRACE_STARTUP_TEST 899 extern int trace_selftest_startup_function(struct tracer *trace, 900 struct trace_array *tr); 901 extern int trace_selftest_startup_function_graph(struct tracer *trace, 902 struct trace_array *tr); 903 extern int trace_selftest_startup_irqsoff(struct tracer *trace, 904 struct trace_array *tr); 905 extern int trace_selftest_startup_preemptoff(struct tracer *trace, 906 struct trace_array *tr); 907 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace, 908 struct trace_array *tr); 909 extern int trace_selftest_startup_wakeup(struct tracer *trace, 910 struct trace_array *tr); 911 extern int trace_selftest_startup_nop(struct tracer *trace, 912 struct trace_array *tr); 913 extern int trace_selftest_startup_branch(struct tracer *trace, 914 struct trace_array *tr); 915 /* 916 * Tracer data references selftest functions that only occur 917 * on boot up. These can be __init functions. Thus, when selftests 918 * are enabled, then the tracers need to reference __init functions. 919 */ 920 #define __tracer_data __refdata 921 #else 922 /* Tracers are seldom changed. Optimize when selftests are disabled. */ 923 #define __tracer_data __read_mostly 924 #endif /* CONFIG_FTRACE_STARTUP_TEST */ 925 926 extern void *head_page(struct trace_array_cpu *data); 927 extern unsigned long long ns2usecs(u64 nsec); 928 extern int 929 trace_vbprintk(unsigned long ip, const char *fmt, va_list args); 930 extern int 931 trace_vprintk(unsigned long ip, const char *fmt, va_list args); 932 extern int 933 trace_array_vprintk(struct trace_array *tr, 934 unsigned long ip, const char *fmt, va_list args); 935 int trace_array_printk_buf(struct trace_buffer *buffer, 936 unsigned long ip, const char *fmt, ...); 937 void trace_printk_seq(struct trace_seq *s); 938 enum print_line_t print_trace_line(struct trace_iterator *iter); 939 940 extern char trace_find_mark(unsigned long long duration); 941 942 struct ftrace_hash; 943 944 struct ftrace_mod_load { 945 struct list_head list; 946 char *func; 947 char *module; 948 int enable; 949 }; 950 951 enum { 952 FTRACE_HASH_FL_MOD = (1 << 0), 953 }; 954 955 struct ftrace_hash { 956 unsigned long size_bits; 957 struct hlist_head *buckets; 958 unsigned long count; 959 unsigned long flags; 960 struct rcu_head rcu; 961 }; 962 963 struct ftrace_func_entry * 964 ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip); 965 966 static __always_inline bool ftrace_hash_empty(struct ftrace_hash *hash) 967 { 968 return !hash || !(hash->count || (hash->flags & FTRACE_HASH_FL_MOD)); 969 } 970 971 /* Standard output formatting function used for function return traces */ 972 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 973 974 /* Flag options */ 975 #define TRACE_GRAPH_PRINT_OVERRUN 0x1 976 #define TRACE_GRAPH_PRINT_CPU 0x2 977 #define TRACE_GRAPH_PRINT_OVERHEAD 0x4 978 #define TRACE_GRAPH_PRINT_PROC 0x8 979 #define TRACE_GRAPH_PRINT_DURATION 0x10 980 #define TRACE_GRAPH_PRINT_ABS_TIME 0x20 981 #define TRACE_GRAPH_PRINT_REL_TIME 0x40 982 #define TRACE_GRAPH_PRINT_IRQS 0x80 983 #define TRACE_GRAPH_PRINT_TAIL 0x100 984 #define TRACE_GRAPH_SLEEP_TIME 0x200 985 #define TRACE_GRAPH_GRAPH_TIME 0x400 986 #define TRACE_GRAPH_PRINT_FILL_SHIFT 28 987 #define TRACE_GRAPH_PRINT_FILL_MASK (0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT) 988 989 extern void ftrace_graph_sleep_time_control(bool enable); 990 991 #ifdef CONFIG_FUNCTION_PROFILER 992 extern void ftrace_graph_graph_time_control(bool enable); 993 #else 994 static inline void ftrace_graph_graph_time_control(bool enable) { } 995 #endif 996 997 extern enum print_line_t 998 print_graph_function_flags(struct trace_iterator *iter, u32 flags); 999 extern void print_graph_headers_flags(struct seq_file *s, u32 flags); 1000 extern void 1001 trace_print_graph_duration(unsigned long long duration, struct trace_seq *s); 1002 extern void graph_trace_open(struct trace_iterator *iter); 1003 extern void graph_trace_close(struct trace_iterator *iter); 1004 extern int __trace_graph_entry(struct trace_array *tr, 1005 struct ftrace_graph_ent *trace, 1006 unsigned long flags, int pc); 1007 extern void __trace_graph_return(struct trace_array *tr, 1008 struct ftrace_graph_ret *trace, 1009 unsigned long flags, int pc); 1010 1011 #ifdef CONFIG_DYNAMIC_FTRACE 1012 extern struct ftrace_hash __rcu *ftrace_graph_hash; 1013 extern struct ftrace_hash __rcu *ftrace_graph_notrace_hash; 1014 1015 static inline int ftrace_graph_addr(struct ftrace_graph_ent *trace) 1016 { 1017 unsigned long addr = trace->func; 1018 int ret = 0; 1019 struct ftrace_hash *hash; 1020 1021 preempt_disable_notrace(); 1022 1023 /* 1024 * Have to open code "rcu_dereference_sched()" because the 1025 * function graph tracer can be called when RCU is not 1026 * "watching". 1027 * Protected with schedule_on_each_cpu(ftrace_sync) 1028 */ 1029 hash = rcu_dereference_protected(ftrace_graph_hash, !preemptible()); 1030 1031 if (ftrace_hash_empty(hash)) { 1032 ret = 1; 1033 goto out; 1034 } 1035 1036 if (ftrace_lookup_ip(hash, addr)) { 1037 1038 /* 1039 * This needs to be cleared on the return functions 1040 * when the depth is zero. 1041 */ 1042 trace_recursion_set(TRACE_GRAPH_BIT); 1043 trace_recursion_set_depth(trace->depth); 1044 1045 /* 1046 * If no irqs are to be traced, but a set_graph_function 1047 * is set, and called by an interrupt handler, we still 1048 * want to trace it. 1049 */ 1050 if (in_irq()) 1051 trace_recursion_set(TRACE_IRQ_BIT); 1052 else 1053 trace_recursion_clear(TRACE_IRQ_BIT); 1054 ret = 1; 1055 } 1056 1057 out: 1058 preempt_enable_notrace(); 1059 return ret; 1060 } 1061 1062 static inline void ftrace_graph_addr_finish(struct ftrace_graph_ret *trace) 1063 { 1064 if (trace_recursion_test(TRACE_GRAPH_BIT) && 1065 trace->depth == trace_recursion_depth()) 1066 trace_recursion_clear(TRACE_GRAPH_BIT); 1067 } 1068 1069 static inline int ftrace_graph_notrace_addr(unsigned long addr) 1070 { 1071 int ret = 0; 1072 struct ftrace_hash *notrace_hash; 1073 1074 preempt_disable_notrace(); 1075 1076 /* 1077 * Have to open code "rcu_dereference_sched()" because the 1078 * function graph tracer can be called when RCU is not 1079 * "watching". 1080 * Protected with schedule_on_each_cpu(ftrace_sync) 1081 */ 1082 notrace_hash = rcu_dereference_protected(ftrace_graph_notrace_hash, 1083 !preemptible()); 1084 1085 if (ftrace_lookup_ip(notrace_hash, addr)) 1086 ret = 1; 1087 1088 preempt_enable_notrace(); 1089 return ret; 1090 } 1091 #else 1092 static inline int ftrace_graph_addr(struct ftrace_graph_ent *trace) 1093 { 1094 return 1; 1095 } 1096 1097 static inline int ftrace_graph_notrace_addr(unsigned long addr) 1098 { 1099 return 0; 1100 } 1101 static inline void ftrace_graph_addr_finish(struct ftrace_graph_ret *trace) 1102 { } 1103 #endif /* CONFIG_DYNAMIC_FTRACE */ 1104 1105 extern unsigned int fgraph_max_depth; 1106 1107 static inline bool ftrace_graph_ignore_func(struct ftrace_graph_ent *trace) 1108 { 1109 /* trace it when it is-nested-in or is a function enabled. */ 1110 return !(trace_recursion_test(TRACE_GRAPH_BIT) || 1111 ftrace_graph_addr(trace)) || 1112 (trace->depth < 0) || 1113 (fgraph_max_depth && trace->depth >= fgraph_max_depth); 1114 } 1115 1116 #else /* CONFIG_FUNCTION_GRAPH_TRACER */ 1117 static inline enum print_line_t 1118 print_graph_function_flags(struct trace_iterator *iter, u32 flags) 1119 { 1120 return TRACE_TYPE_UNHANDLED; 1121 } 1122 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ 1123 1124 extern struct list_head ftrace_pids; 1125 1126 #ifdef CONFIG_FUNCTION_TRACER 1127 1128 #define FTRACE_PID_IGNORE -1 1129 #define FTRACE_PID_TRACE -2 1130 1131 struct ftrace_func_command { 1132 struct list_head list; 1133 char *name; 1134 int (*func)(struct trace_array *tr, 1135 struct ftrace_hash *hash, 1136 char *func, char *cmd, 1137 char *params, int enable); 1138 }; 1139 extern bool ftrace_filter_param __initdata; 1140 static inline int ftrace_trace_task(struct trace_array *tr) 1141 { 1142 return this_cpu_read(tr->array_buffer.data->ftrace_ignore_pid) != 1143 FTRACE_PID_IGNORE; 1144 } 1145 extern int ftrace_is_dead(void); 1146 int ftrace_create_function_files(struct trace_array *tr, 1147 struct dentry *parent); 1148 void ftrace_destroy_function_files(struct trace_array *tr); 1149 int ftrace_allocate_ftrace_ops(struct trace_array *tr); 1150 void ftrace_free_ftrace_ops(struct trace_array *tr); 1151 void ftrace_init_global_array_ops(struct trace_array *tr); 1152 void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func); 1153 void ftrace_reset_array_ops(struct trace_array *tr); 1154 void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer); 1155 void ftrace_init_tracefs_toplevel(struct trace_array *tr, 1156 struct dentry *d_tracer); 1157 void ftrace_clear_pids(struct trace_array *tr); 1158 int init_function_trace(void); 1159 void ftrace_pid_follow_fork(struct trace_array *tr, bool enable); 1160 #else 1161 static inline int ftrace_trace_task(struct trace_array *tr) 1162 { 1163 return 1; 1164 } 1165 static inline int ftrace_is_dead(void) { return 0; } 1166 static inline int 1167 ftrace_create_function_files(struct trace_array *tr, 1168 struct dentry *parent) 1169 { 1170 return 0; 1171 } 1172 static inline int ftrace_allocate_ftrace_ops(struct trace_array *tr) 1173 { 1174 return 0; 1175 } 1176 static inline void ftrace_free_ftrace_ops(struct trace_array *tr) { } 1177 static inline void ftrace_destroy_function_files(struct trace_array *tr) { } 1178 static inline __init void 1179 ftrace_init_global_array_ops(struct trace_array *tr) { } 1180 static inline void ftrace_reset_array_ops(struct trace_array *tr) { } 1181 static inline void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d) { } 1182 static inline void ftrace_init_tracefs_toplevel(struct trace_array *tr, struct dentry *d) { } 1183 static inline void ftrace_clear_pids(struct trace_array *tr) { } 1184 static inline int init_function_trace(void) { return 0; } 1185 static inline void ftrace_pid_follow_fork(struct trace_array *tr, bool enable) { } 1186 /* ftace_func_t type is not defined, use macro instead of static inline */ 1187 #define ftrace_init_array_ops(tr, func) do { } while (0) 1188 #endif /* CONFIG_FUNCTION_TRACER */ 1189 1190 #if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE) 1191 1192 struct ftrace_probe_ops { 1193 void (*func)(unsigned long ip, 1194 unsigned long parent_ip, 1195 struct trace_array *tr, 1196 struct ftrace_probe_ops *ops, 1197 void *data); 1198 int (*init)(struct ftrace_probe_ops *ops, 1199 struct trace_array *tr, 1200 unsigned long ip, void *init_data, 1201 void **data); 1202 void (*free)(struct ftrace_probe_ops *ops, 1203 struct trace_array *tr, 1204 unsigned long ip, void *data); 1205 int (*print)(struct seq_file *m, 1206 unsigned long ip, 1207 struct ftrace_probe_ops *ops, 1208 void *data); 1209 }; 1210 1211 struct ftrace_func_mapper; 1212 typedef int (*ftrace_mapper_func)(void *data); 1213 1214 struct ftrace_func_mapper *allocate_ftrace_func_mapper(void); 1215 void **ftrace_func_mapper_find_ip(struct ftrace_func_mapper *mapper, 1216 unsigned long ip); 1217 int ftrace_func_mapper_add_ip(struct ftrace_func_mapper *mapper, 1218 unsigned long ip, void *data); 1219 void *ftrace_func_mapper_remove_ip(struct ftrace_func_mapper *mapper, 1220 unsigned long ip); 1221 void free_ftrace_func_mapper(struct ftrace_func_mapper *mapper, 1222 ftrace_mapper_func free_func); 1223 1224 extern int 1225 register_ftrace_function_probe(char *glob, struct trace_array *tr, 1226 struct ftrace_probe_ops *ops, void *data); 1227 extern int 1228 unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr, 1229 struct ftrace_probe_ops *ops); 1230 extern void clear_ftrace_function_probes(struct trace_array *tr); 1231 1232 int register_ftrace_command(struct ftrace_func_command *cmd); 1233 int unregister_ftrace_command(struct ftrace_func_command *cmd); 1234 1235 void ftrace_create_filter_files(struct ftrace_ops *ops, 1236 struct dentry *parent); 1237 void ftrace_destroy_filter_files(struct ftrace_ops *ops); 1238 1239 extern int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf, 1240 int len, int reset); 1241 extern int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf, 1242 int len, int reset); 1243 #else 1244 struct ftrace_func_command; 1245 1246 static inline __init int register_ftrace_command(struct ftrace_func_command *cmd) 1247 { 1248 return -EINVAL; 1249 } 1250 static inline __init int unregister_ftrace_command(char *cmd_name) 1251 { 1252 return -EINVAL; 1253 } 1254 static inline void clear_ftrace_function_probes(struct trace_array *tr) 1255 { 1256 } 1257 1258 /* 1259 * The ops parameter passed in is usually undefined. 1260 * This must be a macro. 1261 */ 1262 #define ftrace_create_filter_files(ops, parent) do { } while (0) 1263 #define ftrace_destroy_filter_files(ops) do { } while (0) 1264 #endif /* CONFIG_FUNCTION_TRACER && CONFIG_DYNAMIC_FTRACE */ 1265 1266 bool ftrace_event_is_function(struct trace_event_call *call); 1267 1268 /* 1269 * struct trace_parser - servers for reading the user input separated by spaces 1270 * @cont: set if the input is not complete - no final space char was found 1271 * @buffer: holds the parsed user input 1272 * @idx: user input length 1273 * @size: buffer size 1274 */ 1275 struct trace_parser { 1276 bool cont; 1277 char *buffer; 1278 unsigned idx; 1279 unsigned size; 1280 }; 1281 1282 static inline bool trace_parser_loaded(struct trace_parser *parser) 1283 { 1284 return (parser->idx != 0); 1285 } 1286 1287 static inline bool trace_parser_cont(struct trace_parser *parser) 1288 { 1289 return parser->cont; 1290 } 1291 1292 static inline void trace_parser_clear(struct trace_parser *parser) 1293 { 1294 parser->cont = false; 1295 parser->idx = 0; 1296 } 1297 1298 extern int trace_parser_get_init(struct trace_parser *parser, int size); 1299 extern void trace_parser_put(struct trace_parser *parser); 1300 extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf, 1301 size_t cnt, loff_t *ppos); 1302 1303 /* 1304 * Only create function graph options if function graph is configured. 1305 */ 1306 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 1307 # define FGRAPH_FLAGS \ 1308 C(DISPLAY_GRAPH, "display-graph"), 1309 #else 1310 # define FGRAPH_FLAGS 1311 #endif 1312 1313 #ifdef CONFIG_BRANCH_TRACER 1314 # define BRANCH_FLAGS \ 1315 C(BRANCH, "branch"), 1316 #else 1317 # define BRANCH_FLAGS 1318 #endif 1319 1320 #ifdef CONFIG_FUNCTION_TRACER 1321 # define FUNCTION_FLAGS \ 1322 C(FUNCTION, "function-trace"), \ 1323 C(FUNC_FORK, "function-fork"), 1324 # define FUNCTION_DEFAULT_FLAGS TRACE_ITER_FUNCTION 1325 #else 1326 # define FUNCTION_FLAGS 1327 # define FUNCTION_DEFAULT_FLAGS 0UL 1328 # define TRACE_ITER_FUNC_FORK 0UL 1329 #endif 1330 1331 #ifdef CONFIG_STACKTRACE 1332 # define STACK_FLAGS \ 1333 C(STACKTRACE, "stacktrace"), 1334 #else 1335 # define STACK_FLAGS 1336 #endif 1337 1338 /* 1339 * trace_iterator_flags is an enumeration that defines bit 1340 * positions into trace_flags that controls the output. 1341 * 1342 * NOTE: These bits must match the trace_options array in 1343 * trace.c (this macro guarantees it). 1344 */ 1345 #define TRACE_FLAGS \ 1346 C(PRINT_PARENT, "print-parent"), \ 1347 C(SYM_OFFSET, "sym-offset"), \ 1348 C(SYM_ADDR, "sym-addr"), \ 1349 C(VERBOSE, "verbose"), \ 1350 C(RAW, "raw"), \ 1351 C(HEX, "hex"), \ 1352 C(BIN, "bin"), \ 1353 C(BLOCK, "block"), \ 1354 C(PRINTK, "trace_printk"), \ 1355 C(ANNOTATE, "annotate"), \ 1356 C(USERSTACKTRACE, "userstacktrace"), \ 1357 C(SYM_USEROBJ, "sym-userobj"), \ 1358 C(PRINTK_MSGONLY, "printk-msg-only"), \ 1359 C(CONTEXT_INFO, "context-info"), /* Print pid/cpu/time */ \ 1360 C(LATENCY_FMT, "latency-format"), \ 1361 C(RECORD_CMD, "record-cmd"), \ 1362 C(RECORD_TGID, "record-tgid"), \ 1363 C(OVERWRITE, "overwrite"), \ 1364 C(STOP_ON_FREE, "disable_on_free"), \ 1365 C(IRQ_INFO, "irq-info"), \ 1366 C(MARKERS, "markers"), \ 1367 C(EVENT_FORK, "event-fork"), \ 1368 C(PAUSE_ON_TRACE, "pause-on-trace"), \ 1369 FUNCTION_FLAGS \ 1370 FGRAPH_FLAGS \ 1371 STACK_FLAGS \ 1372 BRANCH_FLAGS 1373 1374 /* 1375 * By defining C, we can make TRACE_FLAGS a list of bit names 1376 * that will define the bits for the flag masks. 1377 */ 1378 #undef C 1379 #define C(a, b) TRACE_ITER_##a##_BIT 1380 1381 enum trace_iterator_bits { 1382 TRACE_FLAGS 1383 /* Make sure we don't go more than we have bits for */ 1384 TRACE_ITER_LAST_BIT 1385 }; 1386 1387 /* 1388 * By redefining C, we can make TRACE_FLAGS a list of masks that 1389 * use the bits as defined above. 1390 */ 1391 #undef C 1392 #define C(a, b) TRACE_ITER_##a = (1 << TRACE_ITER_##a##_BIT) 1393 1394 enum trace_iterator_flags { TRACE_FLAGS }; 1395 1396 /* 1397 * TRACE_ITER_SYM_MASK masks the options in trace_flags that 1398 * control the output of kernel symbols. 1399 */ 1400 #define TRACE_ITER_SYM_MASK \ 1401 (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR) 1402 1403 extern struct tracer nop_trace; 1404 1405 #ifdef CONFIG_BRANCH_TRACER 1406 extern int enable_branch_tracing(struct trace_array *tr); 1407 extern void disable_branch_tracing(void); 1408 static inline int trace_branch_enable(struct trace_array *tr) 1409 { 1410 if (tr->trace_flags & TRACE_ITER_BRANCH) 1411 return enable_branch_tracing(tr); 1412 return 0; 1413 } 1414 static inline void trace_branch_disable(void) 1415 { 1416 /* due to races, always disable */ 1417 disable_branch_tracing(); 1418 } 1419 #else 1420 static inline int trace_branch_enable(struct trace_array *tr) 1421 { 1422 return 0; 1423 } 1424 static inline void trace_branch_disable(void) 1425 { 1426 } 1427 #endif /* CONFIG_BRANCH_TRACER */ 1428 1429 /* set ring buffers to default size if not already done so */ 1430 int tracing_update_buffers(void); 1431 1432 struct ftrace_event_field { 1433 struct list_head link; 1434 const char *name; 1435 const char *type; 1436 int filter_type; 1437 int offset; 1438 int size; 1439 int is_signed; 1440 }; 1441 1442 struct prog_entry; 1443 1444 struct event_filter { 1445 struct prog_entry __rcu *prog; 1446 char *filter_string; 1447 }; 1448 1449 struct event_subsystem { 1450 struct list_head list; 1451 const char *name; 1452 struct event_filter *filter; 1453 int ref_count; 1454 }; 1455 1456 struct trace_subsystem_dir { 1457 struct list_head list; 1458 struct event_subsystem *subsystem; 1459 struct trace_array *tr; 1460 struct dentry *entry; 1461 int ref_count; 1462 int nr_events; 1463 }; 1464 1465 extern int call_filter_check_discard(struct trace_event_call *call, void *rec, 1466 struct trace_buffer *buffer, 1467 struct ring_buffer_event *event); 1468 1469 void trace_buffer_unlock_commit_regs(struct trace_array *tr, 1470 struct trace_buffer *buffer, 1471 struct ring_buffer_event *event, 1472 unsigned long flags, int pc, 1473 struct pt_regs *regs); 1474 1475 static inline void trace_buffer_unlock_commit(struct trace_array *tr, 1476 struct trace_buffer *buffer, 1477 struct ring_buffer_event *event, 1478 unsigned long flags, int pc) 1479 { 1480 trace_buffer_unlock_commit_regs(tr, buffer, event, flags, pc, NULL); 1481 } 1482 1483 DECLARE_PER_CPU(struct ring_buffer_event *, trace_buffered_event); 1484 DECLARE_PER_CPU(int, trace_buffered_event_cnt); 1485 void trace_buffered_event_disable(void); 1486 void trace_buffered_event_enable(void); 1487 1488 static inline void 1489 __trace_event_discard_commit(struct trace_buffer *buffer, 1490 struct ring_buffer_event *event) 1491 { 1492 if (this_cpu_read(trace_buffered_event) == event) { 1493 /* Simply release the temp buffer */ 1494 this_cpu_dec(trace_buffered_event_cnt); 1495 return; 1496 } 1497 ring_buffer_discard_commit(buffer, event); 1498 } 1499 1500 /* 1501 * Helper function for event_trigger_unlock_commit{_regs}(). 1502 * If there are event triggers attached to this event that requires 1503 * filtering against its fields, then they will be called as the 1504 * entry already holds the field information of the current event. 1505 * 1506 * It also checks if the event should be discarded or not. 1507 * It is to be discarded if the event is soft disabled and the 1508 * event was only recorded to process triggers, or if the event 1509 * filter is active and this event did not match the filters. 1510 * 1511 * Returns true if the event is discarded, false otherwise. 1512 */ 1513 static inline bool 1514 __event_trigger_test_discard(struct trace_event_file *file, 1515 struct trace_buffer *buffer, 1516 struct ring_buffer_event *event, 1517 void *entry, 1518 enum event_trigger_type *tt) 1519 { 1520 unsigned long eflags = file->flags; 1521 1522 if (eflags & EVENT_FILE_FL_TRIGGER_COND) 1523 *tt = event_triggers_call(file, entry, event); 1524 1525 if (test_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &file->flags) || 1526 (unlikely(file->flags & EVENT_FILE_FL_FILTERED) && 1527 !filter_match_preds(file->filter, entry))) { 1528 __trace_event_discard_commit(buffer, event); 1529 return true; 1530 } 1531 1532 return false; 1533 } 1534 1535 /** 1536 * event_trigger_unlock_commit - 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 static inline void 1549 event_trigger_unlock_commit(struct trace_event_file *file, 1550 struct trace_buffer *buffer, 1551 struct ring_buffer_event *event, 1552 void *entry, unsigned long irq_flags, int pc) 1553 { 1554 enum event_trigger_type tt = ETT_NONE; 1555 1556 if (!__event_trigger_test_discard(file, buffer, event, entry, &tt)) 1557 trace_buffer_unlock_commit(file->tr, buffer, event, irq_flags, pc); 1558 1559 if (tt) 1560 event_triggers_post_call(file, tt); 1561 } 1562 1563 /** 1564 * event_trigger_unlock_commit_regs - handle triggers and finish event commit 1565 * @file: The file pointer assoctiated to the event 1566 * @buffer: The ring buffer that the event is being written to 1567 * @event: The event meta data in the ring buffer 1568 * @entry: The event itself 1569 * @irq_flags: The state of the interrupts at the start of the event 1570 * @pc: The state of the preempt count at the start of the event. 1571 * 1572 * This is a helper function to handle triggers that require data 1573 * from the event itself. It also tests the event against filters and 1574 * if the event is soft disabled and should be discarded. 1575 * 1576 * Same as event_trigger_unlock_commit() but calls 1577 * trace_buffer_unlock_commit_regs() instead of trace_buffer_unlock_commit(). 1578 */ 1579 static inline void 1580 event_trigger_unlock_commit_regs(struct trace_event_file *file, 1581 struct trace_buffer *buffer, 1582 struct ring_buffer_event *event, 1583 void *entry, unsigned long irq_flags, int pc, 1584 struct pt_regs *regs) 1585 { 1586 enum event_trigger_type tt = ETT_NONE; 1587 1588 if (!__event_trigger_test_discard(file, buffer, event, entry, &tt)) 1589 trace_buffer_unlock_commit_regs(file->tr, buffer, event, 1590 irq_flags, pc, regs); 1591 1592 if (tt) 1593 event_triggers_post_call(file, tt); 1594 } 1595 1596 #define FILTER_PRED_INVALID ((unsigned short)-1) 1597 #define FILTER_PRED_IS_RIGHT (1 << 15) 1598 #define FILTER_PRED_FOLD (1 << 15) 1599 1600 /* 1601 * The max preds is the size of unsigned short with 1602 * two flags at the MSBs. One bit is used for both the IS_RIGHT 1603 * and FOLD flags. The other is reserved. 1604 * 1605 * 2^14 preds is way more than enough. 1606 */ 1607 #define MAX_FILTER_PRED 16384 1608 1609 struct filter_pred; 1610 struct regex; 1611 1612 typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event); 1613 1614 typedef int (*regex_match_func)(char *str, struct regex *r, int len); 1615 1616 enum regex_type { 1617 MATCH_FULL = 0, 1618 MATCH_FRONT_ONLY, 1619 MATCH_MIDDLE_ONLY, 1620 MATCH_END_ONLY, 1621 MATCH_GLOB, 1622 MATCH_INDEX, 1623 }; 1624 1625 struct regex { 1626 char pattern[MAX_FILTER_STR_VAL]; 1627 int len; 1628 int field_len; 1629 regex_match_func match; 1630 }; 1631 1632 struct filter_pred { 1633 filter_pred_fn_t fn; 1634 u64 val; 1635 struct regex regex; 1636 unsigned short *ops; 1637 struct ftrace_event_field *field; 1638 int offset; 1639 int not; 1640 int op; 1641 }; 1642 1643 static inline bool is_string_field(struct ftrace_event_field *field) 1644 { 1645 return field->filter_type == FILTER_DYN_STRING || 1646 field->filter_type == FILTER_STATIC_STRING || 1647 field->filter_type == FILTER_PTR_STRING || 1648 field->filter_type == FILTER_COMM; 1649 } 1650 1651 static inline bool is_function_field(struct ftrace_event_field *field) 1652 { 1653 return field->filter_type == FILTER_TRACE_FN; 1654 } 1655 1656 extern enum regex_type 1657 filter_parse_regex(char *buff, int len, char **search, int *not); 1658 extern void print_event_filter(struct trace_event_file *file, 1659 struct trace_seq *s); 1660 extern int apply_event_filter(struct trace_event_file *file, 1661 char *filter_string); 1662 extern int apply_subsystem_event_filter(struct trace_subsystem_dir *dir, 1663 char *filter_string); 1664 extern void print_subsystem_event_filter(struct event_subsystem *system, 1665 struct trace_seq *s); 1666 extern int filter_assign_type(const char *type); 1667 extern int create_event_filter(struct trace_array *tr, 1668 struct trace_event_call *call, 1669 char *filter_str, bool set_str, 1670 struct event_filter **filterp); 1671 extern void free_event_filter(struct event_filter *filter); 1672 1673 struct ftrace_event_field * 1674 trace_find_event_field(struct trace_event_call *call, char *name); 1675 1676 extern void trace_event_enable_cmd_record(bool enable); 1677 extern void trace_event_enable_tgid_record(bool enable); 1678 1679 extern int event_trace_init(void); 1680 extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr); 1681 extern int event_trace_del_tracer(struct trace_array *tr); 1682 extern void __trace_early_add_events(struct trace_array *tr); 1683 1684 extern struct trace_event_file *__find_event_file(struct trace_array *tr, 1685 const char *system, 1686 const char *event); 1687 extern struct trace_event_file *find_event_file(struct trace_array *tr, 1688 const char *system, 1689 const char *event); 1690 1691 static inline void *event_file_data(struct file *filp) 1692 { 1693 return READ_ONCE(file_inode(filp)->i_private); 1694 } 1695 1696 extern struct mutex event_mutex; 1697 extern struct list_head ftrace_events; 1698 1699 extern const struct file_operations event_trigger_fops; 1700 extern const struct file_operations event_hist_fops; 1701 extern const struct file_operations event_hist_debug_fops; 1702 extern const struct file_operations event_inject_fops; 1703 1704 #ifdef CONFIG_HIST_TRIGGERS 1705 extern int register_trigger_hist_cmd(void); 1706 extern int register_trigger_hist_enable_disable_cmds(void); 1707 #else 1708 static inline int register_trigger_hist_cmd(void) { return 0; } 1709 static inline int register_trigger_hist_enable_disable_cmds(void) { return 0; } 1710 #endif 1711 1712 extern int register_trigger_cmds(void); 1713 extern void clear_event_triggers(struct trace_array *tr); 1714 1715 struct event_trigger_data { 1716 unsigned long count; 1717 int ref; 1718 struct event_trigger_ops *ops; 1719 struct event_command *cmd_ops; 1720 struct event_filter __rcu *filter; 1721 char *filter_str; 1722 void *private_data; 1723 bool paused; 1724 bool paused_tmp; 1725 struct list_head list; 1726 char *name; 1727 struct list_head named_list; 1728 struct event_trigger_data *named_data; 1729 }; 1730 1731 /* Avoid typos */ 1732 #define ENABLE_EVENT_STR "enable_event" 1733 #define DISABLE_EVENT_STR "disable_event" 1734 #define ENABLE_HIST_STR "enable_hist" 1735 #define DISABLE_HIST_STR "disable_hist" 1736 1737 struct enable_trigger_data { 1738 struct trace_event_file *file; 1739 bool enable; 1740 bool hist; 1741 }; 1742 1743 extern int event_enable_trigger_print(struct seq_file *m, 1744 struct event_trigger_ops *ops, 1745 struct event_trigger_data *data); 1746 extern void event_enable_trigger_free(struct event_trigger_ops *ops, 1747 struct event_trigger_data *data); 1748 extern int event_enable_trigger_func(struct event_command *cmd_ops, 1749 struct trace_event_file *file, 1750 char *glob, char *cmd, char *param); 1751 extern int event_enable_register_trigger(char *glob, 1752 struct event_trigger_ops *ops, 1753 struct event_trigger_data *data, 1754 struct trace_event_file *file); 1755 extern void event_enable_unregister_trigger(char *glob, 1756 struct event_trigger_ops *ops, 1757 struct event_trigger_data *test, 1758 struct trace_event_file *file); 1759 extern void trigger_data_free(struct event_trigger_data *data); 1760 extern int event_trigger_init(struct event_trigger_ops *ops, 1761 struct event_trigger_data *data); 1762 extern int trace_event_trigger_enable_disable(struct trace_event_file *file, 1763 int trigger_enable); 1764 extern void update_cond_flag(struct trace_event_file *file); 1765 extern int set_trigger_filter(char *filter_str, 1766 struct event_trigger_data *trigger_data, 1767 struct trace_event_file *file); 1768 extern struct event_trigger_data *find_named_trigger(const char *name); 1769 extern bool is_named_trigger(struct event_trigger_data *test); 1770 extern int save_named_trigger(const char *name, 1771 struct event_trigger_data *data); 1772 extern void del_named_trigger(struct event_trigger_data *data); 1773 extern void pause_named_trigger(struct event_trigger_data *data); 1774 extern void unpause_named_trigger(struct event_trigger_data *data); 1775 extern void set_named_trigger_data(struct event_trigger_data *data, 1776 struct event_trigger_data *named_data); 1777 extern struct event_trigger_data * 1778 get_named_trigger_data(struct event_trigger_data *data); 1779 extern int register_event_command(struct event_command *cmd); 1780 extern int unregister_event_command(struct event_command *cmd); 1781 extern int register_trigger_hist_enable_disable_cmds(void); 1782 1783 /** 1784 * struct event_trigger_ops - callbacks for trace event triggers 1785 * 1786 * The methods in this structure provide per-event trigger hooks for 1787 * various trigger operations. 1788 * 1789 * All the methods below, except for @init() and @free(), must be 1790 * implemented. 1791 * 1792 * @func: The trigger 'probe' function called when the triggering 1793 * event occurs. The data passed into this callback is the data 1794 * that was supplied to the event_command @reg() function that 1795 * registered the trigger (see struct event_command) along with 1796 * the trace record, rec. 1797 * 1798 * @init: An optional initialization function called for the trigger 1799 * when the trigger is registered (via the event_command reg() 1800 * function). This can be used to perform per-trigger 1801 * initialization such as incrementing a per-trigger reference 1802 * count, for instance. This is usually implemented by the 1803 * generic utility function @event_trigger_init() (see 1804 * trace_event_triggers.c). 1805 * 1806 * @free: An optional de-initialization function called for the 1807 * trigger when the trigger is unregistered (via the 1808 * event_command @reg() function). This can be used to perform 1809 * per-trigger de-initialization such as decrementing a 1810 * per-trigger reference count and freeing corresponding trigger 1811 * data, for instance. This is usually implemented by the 1812 * generic utility function @event_trigger_free() (see 1813 * trace_event_triggers.c). 1814 * 1815 * @print: The callback function invoked to have the trigger print 1816 * itself. This is usually implemented by a wrapper function 1817 * that calls the generic utility function @event_trigger_print() 1818 * (see trace_event_triggers.c). 1819 */ 1820 struct event_trigger_ops { 1821 void (*func)(struct event_trigger_data *data, 1822 void *rec, 1823 struct ring_buffer_event *rbe); 1824 int (*init)(struct event_trigger_ops *ops, 1825 struct event_trigger_data *data); 1826 void (*free)(struct event_trigger_ops *ops, 1827 struct event_trigger_data *data); 1828 int (*print)(struct seq_file *m, 1829 struct event_trigger_ops *ops, 1830 struct event_trigger_data *data); 1831 }; 1832 1833 /** 1834 * struct event_command - callbacks and data members for event commands 1835 * 1836 * Event commands are invoked by users by writing the command name 1837 * into the 'trigger' file associated with a trace event. The 1838 * parameters associated with a specific invocation of an event 1839 * command are used to create an event trigger instance, which is 1840 * added to the list of trigger instances associated with that trace 1841 * event. When the event is hit, the set of triggers associated with 1842 * that event is invoked. 1843 * 1844 * The data members in this structure provide per-event command data 1845 * for various event commands. 1846 * 1847 * All the data members below, except for @post_trigger, must be set 1848 * for each event command. 1849 * 1850 * @name: The unique name that identifies the event command. This is 1851 * the name used when setting triggers via trigger files. 1852 * 1853 * @trigger_type: A unique id that identifies the event command 1854 * 'type'. This value has two purposes, the first to ensure that 1855 * only one trigger of the same type can be set at a given time 1856 * for a particular event e.g. it doesn't make sense to have both 1857 * a traceon and traceoff trigger attached to a single event at 1858 * the same time, so traceon and traceoff have the same type 1859 * though they have different names. The @trigger_type value is 1860 * also used as a bit value for deferring the actual trigger 1861 * action until after the current event is finished. Some 1862 * commands need to do this if they themselves log to the trace 1863 * buffer (see the @post_trigger() member below). @trigger_type 1864 * values are defined by adding new values to the trigger_type 1865 * enum in include/linux/trace_events.h. 1866 * 1867 * @flags: See the enum event_command_flags below. 1868 * 1869 * All the methods below, except for @set_filter() and @unreg_all(), 1870 * must be implemented. 1871 * 1872 * @func: The callback function responsible for parsing and 1873 * registering the trigger written to the 'trigger' file by the 1874 * user. It allocates the trigger instance and registers it with 1875 * the appropriate trace event. It makes use of the other 1876 * event_command callback functions to orchestrate this, and is 1877 * usually implemented by the generic utility function 1878 * @event_trigger_callback() (see trace_event_triggers.c). 1879 * 1880 * @reg: Adds the trigger to the list of triggers associated with the 1881 * event, and enables the event trigger itself, after 1882 * initializing it (via the event_trigger_ops @init() function). 1883 * This is also where commands can use the @trigger_type value to 1884 * make the decision as to whether or not multiple instances of 1885 * the trigger should be allowed. This is usually implemented by 1886 * the generic utility function @register_trigger() (see 1887 * trace_event_triggers.c). 1888 * 1889 * @unreg: Removes the trigger from the list of triggers associated 1890 * with the event, and disables the event trigger itself, after 1891 * initializing it (via the event_trigger_ops @free() function). 1892 * This is usually implemented by the generic utility function 1893 * @unregister_trigger() (see trace_event_triggers.c). 1894 * 1895 * @unreg_all: An optional function called to remove all the triggers 1896 * from the list of triggers associated with the event. Called 1897 * when a trigger file is opened in truncate mode. 1898 * 1899 * @set_filter: An optional function called to parse and set a filter 1900 * for the trigger. If no @set_filter() method is set for the 1901 * event command, filters set by the user for the command will be 1902 * ignored. This is usually implemented by the generic utility 1903 * function @set_trigger_filter() (see trace_event_triggers.c). 1904 * 1905 * @get_trigger_ops: The callback function invoked to retrieve the 1906 * event_trigger_ops implementation associated with the command. 1907 */ 1908 struct event_command { 1909 struct list_head list; 1910 char *name; 1911 enum event_trigger_type trigger_type; 1912 int flags; 1913 int (*func)(struct event_command *cmd_ops, 1914 struct trace_event_file *file, 1915 char *glob, char *cmd, char *params); 1916 int (*reg)(char *glob, 1917 struct event_trigger_ops *ops, 1918 struct event_trigger_data *data, 1919 struct trace_event_file *file); 1920 void (*unreg)(char *glob, 1921 struct event_trigger_ops *ops, 1922 struct event_trigger_data *data, 1923 struct trace_event_file *file); 1924 void (*unreg_all)(struct trace_event_file *file); 1925 int (*set_filter)(char *filter_str, 1926 struct event_trigger_data *data, 1927 struct trace_event_file *file); 1928 struct event_trigger_ops *(*get_trigger_ops)(char *cmd, char *param); 1929 }; 1930 1931 /** 1932 * enum event_command_flags - flags for struct event_command 1933 * 1934 * @POST_TRIGGER: A flag that says whether or not this command needs 1935 * to have its action delayed until after the current event has 1936 * been closed. Some triggers need to avoid being invoked while 1937 * an event is currently in the process of being logged, since 1938 * the trigger may itself log data into the trace buffer. Thus 1939 * we make sure the current event is committed before invoking 1940 * those triggers. To do that, the trigger invocation is split 1941 * in two - the first part checks the filter using the current 1942 * trace record; if a command has the @post_trigger flag set, it 1943 * sets a bit for itself in the return value, otherwise it 1944 * directly invokes the trigger. Once all commands have been 1945 * either invoked or set their return flag, the current record is 1946 * either committed or discarded. At that point, if any commands 1947 * have deferred their triggers, those commands are finally 1948 * invoked following the close of the current event. In other 1949 * words, if the event_trigger_ops @func() probe implementation 1950 * itself logs to the trace buffer, this flag should be set, 1951 * otherwise it can be left unspecified. 1952 * 1953 * @NEEDS_REC: A flag that says whether or not this command needs 1954 * access to the trace record in order to perform its function, 1955 * regardless of whether or not it has a filter associated with 1956 * it (filters make a trigger require access to the trace record 1957 * but are not always present). 1958 */ 1959 enum event_command_flags { 1960 EVENT_CMD_FL_POST_TRIGGER = 1, 1961 EVENT_CMD_FL_NEEDS_REC = 2, 1962 }; 1963 1964 static inline bool event_command_post_trigger(struct event_command *cmd_ops) 1965 { 1966 return cmd_ops->flags & EVENT_CMD_FL_POST_TRIGGER; 1967 } 1968 1969 static inline bool event_command_needs_rec(struct event_command *cmd_ops) 1970 { 1971 return cmd_ops->flags & EVENT_CMD_FL_NEEDS_REC; 1972 } 1973 1974 extern int trace_event_enable_disable(struct trace_event_file *file, 1975 int enable, int soft_disable); 1976 extern int tracing_alloc_snapshot(void); 1977 extern void tracing_snapshot_cond(struct trace_array *tr, void *cond_data); 1978 extern int tracing_snapshot_cond_enable(struct trace_array *tr, void *cond_data, cond_update_fn_t update); 1979 1980 extern int tracing_snapshot_cond_disable(struct trace_array *tr); 1981 extern void *tracing_cond_snapshot_data(struct trace_array *tr); 1982 1983 extern const char *__start___trace_bprintk_fmt[]; 1984 extern const char *__stop___trace_bprintk_fmt[]; 1985 1986 extern const char *__start___tracepoint_str[]; 1987 extern const char *__stop___tracepoint_str[]; 1988 1989 void trace_printk_control(bool enabled); 1990 void trace_printk_start_comm(void); 1991 int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set); 1992 int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled); 1993 1994 /* Used from boot time tracer */ 1995 extern int trace_set_options(struct trace_array *tr, char *option); 1996 extern int tracing_set_tracer(struct trace_array *tr, const char *buf); 1997 extern ssize_t tracing_resize_ring_buffer(struct trace_array *tr, 1998 unsigned long size, int cpu_id); 1999 extern int tracing_set_cpumask(struct trace_array *tr, 2000 cpumask_var_t tracing_cpumask_new); 2001 2002 2003 #define MAX_EVENT_NAME_LEN 64 2004 2005 extern int trace_run_command(const char *buf, int (*createfn)(int, char**)); 2006 extern ssize_t trace_parse_run_command(struct file *file, 2007 const char __user *buffer, size_t count, loff_t *ppos, 2008 int (*createfn)(int, char**)); 2009 2010 extern unsigned int err_pos(char *cmd, const char *str); 2011 extern void tracing_log_err(struct trace_array *tr, 2012 const char *loc, const char *cmd, 2013 const char **errs, u8 type, u8 pos); 2014 2015 /* 2016 * Normal trace_printk() and friends allocates special buffers 2017 * to do the manipulation, as well as saves the print formats 2018 * into sections to display. But the trace infrastructure wants 2019 * to use these without the added overhead at the price of being 2020 * a bit slower (used mainly for warnings, where we don't care 2021 * about performance). The internal_trace_puts() is for such 2022 * a purpose. 2023 */ 2024 #define internal_trace_puts(str) __trace_puts(_THIS_IP_, str, strlen(str)) 2025 2026 #undef FTRACE_ENTRY 2027 #define FTRACE_ENTRY(call, struct_name, id, tstruct, print) \ 2028 extern struct trace_event_call \ 2029 __aligned(4) event_##call; 2030 #undef FTRACE_ENTRY_DUP 2031 #define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print) \ 2032 FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print)) 2033 #undef FTRACE_ENTRY_PACKED 2034 #define FTRACE_ENTRY_PACKED(call, struct_name, id, tstruct, print) \ 2035 FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print)) 2036 2037 #include "trace_entries.h" 2038 2039 #if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER) 2040 int perf_ftrace_event_register(struct trace_event_call *call, 2041 enum trace_reg type, void *data); 2042 #else 2043 #define perf_ftrace_event_register NULL 2044 #endif 2045 2046 #ifdef CONFIG_FTRACE_SYSCALLS 2047 void init_ftrace_syscalls(void); 2048 const char *get_syscall_name(int syscall); 2049 #else 2050 static inline void init_ftrace_syscalls(void) { } 2051 static inline const char *get_syscall_name(int syscall) 2052 { 2053 return NULL; 2054 } 2055 #endif 2056 2057 #ifdef CONFIG_EVENT_TRACING 2058 void trace_event_init(void); 2059 void trace_event_eval_update(struct trace_eval_map **map, int len); 2060 /* Used from boot time tracer */ 2061 extern int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set); 2062 extern int trigger_process_regex(struct trace_event_file *file, char *buff); 2063 #else 2064 static inline void __init trace_event_init(void) { } 2065 static inline void trace_event_eval_update(struct trace_eval_map **map, int len) { } 2066 #endif 2067 2068 #ifdef CONFIG_TRACER_SNAPSHOT 2069 void tracing_snapshot_instance(struct trace_array *tr); 2070 int tracing_alloc_snapshot_instance(struct trace_array *tr); 2071 #else 2072 static inline void tracing_snapshot_instance(struct trace_array *tr) { } 2073 static inline int tracing_alloc_snapshot_instance(struct trace_array *tr) 2074 { 2075 return 0; 2076 } 2077 #endif 2078 2079 #ifdef CONFIG_PREEMPT_TRACER 2080 void tracer_preempt_on(unsigned long a0, unsigned long a1); 2081 void tracer_preempt_off(unsigned long a0, unsigned long a1); 2082 #else 2083 static inline void tracer_preempt_on(unsigned long a0, unsigned long a1) { } 2084 static inline void tracer_preempt_off(unsigned long a0, unsigned long a1) { } 2085 #endif 2086 #ifdef CONFIG_IRQSOFF_TRACER 2087 void tracer_hardirqs_on(unsigned long a0, unsigned long a1); 2088 void tracer_hardirqs_off(unsigned long a0, unsigned long a1); 2089 #else 2090 static inline void tracer_hardirqs_on(unsigned long a0, unsigned long a1) { } 2091 static inline void tracer_hardirqs_off(unsigned long a0, unsigned long a1) { } 2092 #endif 2093 2094 extern struct trace_iterator *tracepoint_print_iter; 2095 2096 /* 2097 * Reset the state of the trace_iterator so that it can read consumed data. 2098 * Normally, the trace_iterator is used for reading the data when it is not 2099 * consumed, and must retain state. 2100 */ 2101 static __always_inline void trace_iterator_reset(struct trace_iterator *iter) 2102 { 2103 const size_t offset = offsetof(struct trace_iterator, seq); 2104 2105 /* 2106 * Keep gcc from complaining about overwriting more than just one 2107 * member in the structure. 2108 */ 2109 memset((char *)iter + offset, 0, sizeof(struct trace_iterator) - offset); 2110 2111 iter->pos = -1; 2112 } 2113 2114 /* Check the name is good for event/group/fields */ 2115 static inline bool is_good_name(const char *name) 2116 { 2117 if (!isalpha(*name) && *name != '_') 2118 return false; 2119 while (*++name != '\0') { 2120 if (!isalpha(*name) && !isdigit(*name) && *name != '_') 2121 return false; 2122 } 2123 return true; 2124 } 2125 2126 #endif /* _LINUX_KERNEL_TRACE_H */ 2127