1 /* 2 * Ftrace header. For implementation details beyond the random comments 3 * scattered below, see: Documentation/trace/ftrace-design.txt 4 */ 5 6 #ifndef _LINUX_FTRACE_H 7 #define _LINUX_FTRACE_H 8 9 #include <linux/trace_clock.h> 10 #include <linux/kallsyms.h> 11 #include <linux/linkage.h> 12 #include <linux/bitops.h> 13 #include <linux/ptrace.h> 14 #include <linux/ktime.h> 15 #include <linux/sched.h> 16 #include <linux/types.h> 17 #include <linux/init.h> 18 #include <linux/fs.h> 19 20 #include <asm/ftrace.h> 21 22 /* 23 * If the arch supports passing the variable contents of 24 * function_trace_op as the third parameter back from the 25 * mcount call, then the arch should define this as 1. 26 */ 27 #ifndef ARCH_SUPPORTS_FTRACE_OPS 28 #define ARCH_SUPPORTS_FTRACE_OPS 0 29 #endif 30 31 /* 32 * If the arch's mcount caller does not support all of ftrace's 33 * features, then it must call an indirect function that 34 * does. Or at least does enough to prevent any unwelcomed side effects. 35 */ 36 #if !ARCH_SUPPORTS_FTRACE_OPS 37 # define FTRACE_FORCE_LIST_FUNC 1 38 #else 39 # define FTRACE_FORCE_LIST_FUNC 0 40 #endif 41 42 /* Main tracing buffer and events set up */ 43 #ifdef CONFIG_TRACING 44 void trace_init(void); 45 #else 46 static inline void trace_init(void) { } 47 #endif 48 49 struct module; 50 struct ftrace_hash; 51 52 #ifdef CONFIG_FUNCTION_TRACER 53 54 extern int ftrace_enabled; 55 extern int 56 ftrace_enable_sysctl(struct ctl_table *table, int write, 57 void __user *buffer, size_t *lenp, 58 loff_t *ppos); 59 60 struct ftrace_ops; 61 62 typedef void (*ftrace_func_t)(unsigned long ip, unsigned long parent_ip, 63 struct ftrace_ops *op, struct pt_regs *regs); 64 65 ftrace_func_t ftrace_ops_get_func(struct ftrace_ops *ops); 66 67 /* 68 * FTRACE_OPS_FL_* bits denote the state of ftrace_ops struct and are 69 * set in the flags member. 70 * CONTROL, SAVE_REGS, SAVE_REGS_IF_SUPPORTED, RECURSION_SAFE, STUB and 71 * IPMODIFY are a kind of attribute flags which can be set only before 72 * registering the ftrace_ops, and can not be modified while registered. 73 * Changing those attribute flags after regsitering ftrace_ops will 74 * cause unexpected results. 75 * 76 * ENABLED - set/unset when ftrace_ops is registered/unregistered 77 * DYNAMIC - set when ftrace_ops is registered to denote dynamically 78 * allocated ftrace_ops which need special care 79 * CONTROL - set manualy by ftrace_ops user to denote the ftrace_ops 80 * could be controled by following calls: 81 * ftrace_function_local_enable 82 * ftrace_function_local_disable 83 * SAVE_REGS - The ftrace_ops wants regs saved at each function called 84 * and passed to the callback. If this flag is set, but the 85 * architecture does not support passing regs 86 * (CONFIG_DYNAMIC_FTRACE_WITH_REGS is not defined), then the 87 * ftrace_ops will fail to register, unless the next flag 88 * is set. 89 * SAVE_REGS_IF_SUPPORTED - This is the same as SAVE_REGS, but if the 90 * handler can handle an arch that does not save regs 91 * (the handler tests if regs == NULL), then it can set 92 * this flag instead. It will not fail registering the ftrace_ops 93 * but, the regs field will be NULL if the arch does not support 94 * passing regs to the handler. 95 * Note, if this flag is set, the SAVE_REGS flag will automatically 96 * get set upon registering the ftrace_ops, if the arch supports it. 97 * RECURSION_SAFE - The ftrace_ops can set this to tell the ftrace infrastructure 98 * that the call back has its own recursion protection. If it does 99 * not set this, then the ftrace infrastructure will add recursion 100 * protection for the caller. 101 * STUB - The ftrace_ops is just a place holder. 102 * INITIALIZED - The ftrace_ops has already been initialized (first use time 103 * register_ftrace_function() is called, it will initialized the ops) 104 * DELETED - The ops are being deleted, do not let them be registered again. 105 * ADDING - The ops is in the process of being added. 106 * REMOVING - The ops is in the process of being removed. 107 * MODIFYING - The ops is in the process of changing its filter functions. 108 * ALLOC_TRAMP - A dynamic trampoline was allocated by the core code. 109 * The arch specific code sets this flag when it allocated a 110 * trampoline. This lets the arch know that it can update the 111 * trampoline in case the callback function changes. 112 * The ftrace_ops trampoline can be set by the ftrace users, and 113 * in such cases the arch must not modify it. Only the arch ftrace 114 * core code should set this flag. 115 * IPMODIFY - The ops can modify the IP register. This can only be set with 116 * SAVE_REGS. If another ops with this flag set is already registered 117 * for any of the functions that this ops will be registered for, then 118 * this ops will fail to register or set_filter_ip. 119 * PID - Is affected by set_ftrace_pid (allows filtering on those pids) 120 */ 121 enum { 122 FTRACE_OPS_FL_ENABLED = 1 << 0, 123 FTRACE_OPS_FL_DYNAMIC = 1 << 1, 124 FTRACE_OPS_FL_CONTROL = 1 << 2, 125 FTRACE_OPS_FL_SAVE_REGS = 1 << 3, 126 FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED = 1 << 4, 127 FTRACE_OPS_FL_RECURSION_SAFE = 1 << 5, 128 FTRACE_OPS_FL_STUB = 1 << 6, 129 FTRACE_OPS_FL_INITIALIZED = 1 << 7, 130 FTRACE_OPS_FL_DELETED = 1 << 8, 131 FTRACE_OPS_FL_ADDING = 1 << 9, 132 FTRACE_OPS_FL_REMOVING = 1 << 10, 133 FTRACE_OPS_FL_MODIFYING = 1 << 11, 134 FTRACE_OPS_FL_ALLOC_TRAMP = 1 << 12, 135 FTRACE_OPS_FL_IPMODIFY = 1 << 13, 136 FTRACE_OPS_FL_PID = 1 << 14, 137 }; 138 139 #ifdef CONFIG_DYNAMIC_FTRACE 140 /* The hash used to know what functions callbacks trace */ 141 struct ftrace_ops_hash { 142 struct ftrace_hash *notrace_hash; 143 struct ftrace_hash *filter_hash; 144 struct mutex regex_lock; 145 }; 146 #endif 147 148 /* 149 * Note, ftrace_ops can be referenced outside of RCU protection. 150 * (Although, for perf, the control ops prevent that). If ftrace_ops is 151 * allocated and not part of kernel core data, the unregistering of it will 152 * perform a scheduling on all CPUs to make sure that there are no more users. 153 * Depending on the load of the system that may take a bit of time. 154 * 155 * Any private data added must also take care not to be freed and if private 156 * data is added to a ftrace_ops that is in core code, the user of the 157 * ftrace_ops must perform a schedule_on_each_cpu() before freeing it. 158 */ 159 struct ftrace_ops { 160 ftrace_func_t func; 161 struct ftrace_ops *next; 162 unsigned long flags; 163 void *private; 164 ftrace_func_t saved_func; 165 int __percpu *disabled; 166 #ifdef CONFIG_DYNAMIC_FTRACE 167 int nr_trampolines; 168 struct ftrace_ops_hash local_hash; 169 struct ftrace_ops_hash *func_hash; 170 struct ftrace_ops_hash old_hash; 171 unsigned long trampoline; 172 unsigned long trampoline_size; 173 #endif 174 }; 175 176 /* 177 * Type of the current tracing. 178 */ 179 enum ftrace_tracing_type_t { 180 FTRACE_TYPE_ENTER = 0, /* Hook the call of the function */ 181 FTRACE_TYPE_RETURN, /* Hook the return of the function */ 182 }; 183 184 /* Current tracing type, default is FTRACE_TYPE_ENTER */ 185 extern enum ftrace_tracing_type_t ftrace_tracing_type; 186 187 /* 188 * The ftrace_ops must be a static and should also 189 * be read_mostly. These functions do modify read_mostly variables 190 * so use them sparely. Never free an ftrace_op or modify the 191 * next pointer after it has been registered. Even after unregistering 192 * it, the next pointer may still be used internally. 193 */ 194 int register_ftrace_function(struct ftrace_ops *ops); 195 int unregister_ftrace_function(struct ftrace_ops *ops); 196 void clear_ftrace_function(void); 197 198 /** 199 * ftrace_function_local_enable - enable controlled ftrace_ops on current cpu 200 * 201 * This function enables tracing on current cpu by decreasing 202 * the per cpu control variable. 203 * It must be called with preemption disabled and only on ftrace_ops 204 * registered with FTRACE_OPS_FL_CONTROL. If called without preemption 205 * disabled, this_cpu_ptr will complain when CONFIG_DEBUG_PREEMPT is enabled. 206 */ 207 static inline void ftrace_function_local_enable(struct ftrace_ops *ops) 208 { 209 if (WARN_ON_ONCE(!(ops->flags & FTRACE_OPS_FL_CONTROL))) 210 return; 211 212 (*this_cpu_ptr(ops->disabled))--; 213 } 214 215 /** 216 * ftrace_function_local_disable - enable controlled ftrace_ops on current cpu 217 * 218 * This function enables tracing on current cpu by decreasing 219 * the per cpu control variable. 220 * It must be called with preemption disabled and only on ftrace_ops 221 * registered with FTRACE_OPS_FL_CONTROL. If called without preemption 222 * disabled, this_cpu_ptr will complain when CONFIG_DEBUG_PREEMPT is enabled. 223 */ 224 static inline void ftrace_function_local_disable(struct ftrace_ops *ops) 225 { 226 if (WARN_ON_ONCE(!(ops->flags & FTRACE_OPS_FL_CONTROL))) 227 return; 228 229 (*this_cpu_ptr(ops->disabled))++; 230 } 231 232 /** 233 * ftrace_function_local_disabled - returns ftrace_ops disabled value 234 * on current cpu 235 * 236 * This function returns value of ftrace_ops::disabled on current cpu. 237 * It must be called with preemption disabled and only on ftrace_ops 238 * registered with FTRACE_OPS_FL_CONTROL. If called without preemption 239 * disabled, this_cpu_ptr will complain when CONFIG_DEBUG_PREEMPT is enabled. 240 */ 241 static inline int ftrace_function_local_disabled(struct ftrace_ops *ops) 242 { 243 WARN_ON_ONCE(!(ops->flags & FTRACE_OPS_FL_CONTROL)); 244 return *this_cpu_ptr(ops->disabled); 245 } 246 247 extern void ftrace_stub(unsigned long a0, unsigned long a1, 248 struct ftrace_ops *op, struct pt_regs *regs); 249 250 #else /* !CONFIG_FUNCTION_TRACER */ 251 /* 252 * (un)register_ftrace_function must be a macro since the ops parameter 253 * must not be evaluated. 254 */ 255 #define register_ftrace_function(ops) ({ 0; }) 256 #define unregister_ftrace_function(ops) ({ 0; }) 257 static inline int ftrace_nr_registered_ops(void) 258 { 259 return 0; 260 } 261 static inline void clear_ftrace_function(void) { } 262 static inline void ftrace_kill(void) { } 263 #endif /* CONFIG_FUNCTION_TRACER */ 264 265 #ifdef CONFIG_STACK_TRACER 266 267 #define STACK_TRACE_ENTRIES 500 268 269 struct stack_trace; 270 271 extern unsigned stack_trace_index[]; 272 extern struct stack_trace stack_trace_max; 273 extern unsigned long stack_trace_max_size; 274 extern arch_spinlock_t stack_trace_max_lock; 275 276 extern int stack_tracer_enabled; 277 void stack_trace_print(void); 278 int 279 stack_trace_sysctl(struct ctl_table *table, int write, 280 void __user *buffer, size_t *lenp, 281 loff_t *ppos); 282 #endif 283 284 struct ftrace_func_command { 285 struct list_head list; 286 char *name; 287 int (*func)(struct ftrace_hash *hash, 288 char *func, char *cmd, 289 char *params, int enable); 290 }; 291 292 #ifdef CONFIG_DYNAMIC_FTRACE 293 294 int ftrace_arch_code_modify_prepare(void); 295 int ftrace_arch_code_modify_post_process(void); 296 297 struct dyn_ftrace; 298 299 void ftrace_bug(int err, struct dyn_ftrace *rec); 300 301 struct seq_file; 302 303 struct ftrace_probe_ops { 304 void (*func)(unsigned long ip, 305 unsigned long parent_ip, 306 void **data); 307 int (*init)(struct ftrace_probe_ops *ops, 308 unsigned long ip, void **data); 309 void (*free)(struct ftrace_probe_ops *ops, 310 unsigned long ip, void **data); 311 int (*print)(struct seq_file *m, 312 unsigned long ip, 313 struct ftrace_probe_ops *ops, 314 void *data); 315 }; 316 317 extern int 318 register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, 319 void *data); 320 extern void 321 unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, 322 void *data); 323 extern void 324 unregister_ftrace_function_probe_func(char *glob, struct ftrace_probe_ops *ops); 325 extern void unregister_ftrace_function_probe_all(char *glob); 326 327 extern int ftrace_text_reserved(const void *start, const void *end); 328 329 extern int ftrace_nr_registered_ops(void); 330 331 bool is_ftrace_trampoline(unsigned long addr); 332 333 /* 334 * The dyn_ftrace record's flags field is split into two parts. 335 * the first part which is '0-FTRACE_REF_MAX' is a counter of 336 * the number of callbacks that have registered the function that 337 * the dyn_ftrace descriptor represents. 338 * 339 * The second part is a mask: 340 * ENABLED - the function is being traced 341 * REGS - the record wants the function to save regs 342 * REGS_EN - the function is set up to save regs. 343 * IPMODIFY - the record allows for the IP address to be changed. 344 * 345 * When a new ftrace_ops is registered and wants a function to save 346 * pt_regs, the rec->flag REGS is set. When the function has been 347 * set up to save regs, the REG_EN flag is set. Once a function 348 * starts saving regs it will do so until all ftrace_ops are removed 349 * from tracing that function. 350 */ 351 enum { 352 FTRACE_FL_ENABLED = (1UL << 31), 353 FTRACE_FL_REGS = (1UL << 30), 354 FTRACE_FL_REGS_EN = (1UL << 29), 355 FTRACE_FL_TRAMP = (1UL << 28), 356 FTRACE_FL_TRAMP_EN = (1UL << 27), 357 FTRACE_FL_IPMODIFY = (1UL << 26), 358 }; 359 360 #define FTRACE_REF_MAX_SHIFT 26 361 #define FTRACE_FL_BITS 6 362 #define FTRACE_FL_MASKED_BITS ((1UL << FTRACE_FL_BITS) - 1) 363 #define FTRACE_FL_MASK (FTRACE_FL_MASKED_BITS << FTRACE_REF_MAX_SHIFT) 364 #define FTRACE_REF_MAX ((1UL << FTRACE_REF_MAX_SHIFT) - 1) 365 366 #define ftrace_rec_count(rec) ((rec)->flags & ~FTRACE_FL_MASK) 367 368 struct dyn_ftrace { 369 unsigned long ip; /* address of mcount call-site */ 370 unsigned long flags; 371 struct dyn_arch_ftrace arch; 372 }; 373 374 int ftrace_force_update(void); 375 int ftrace_set_filter_ip(struct ftrace_ops *ops, unsigned long ip, 376 int remove, int reset); 377 int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf, 378 int len, int reset); 379 int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf, 380 int len, int reset); 381 void ftrace_set_global_filter(unsigned char *buf, int len, int reset); 382 void ftrace_set_global_notrace(unsigned char *buf, int len, int reset); 383 void ftrace_free_filter(struct ftrace_ops *ops); 384 385 int register_ftrace_command(struct ftrace_func_command *cmd); 386 int unregister_ftrace_command(struct ftrace_func_command *cmd); 387 388 enum { 389 FTRACE_UPDATE_CALLS = (1 << 0), 390 FTRACE_DISABLE_CALLS = (1 << 1), 391 FTRACE_UPDATE_TRACE_FUNC = (1 << 2), 392 FTRACE_START_FUNC_RET = (1 << 3), 393 FTRACE_STOP_FUNC_RET = (1 << 4), 394 }; 395 396 /* 397 * The FTRACE_UPDATE_* enum is used to pass information back 398 * from the ftrace_update_record() and ftrace_test_record() 399 * functions. These are called by the code update routines 400 * to find out what is to be done for a given function. 401 * 402 * IGNORE - The function is already what we want it to be 403 * MAKE_CALL - Start tracing the function 404 * MODIFY_CALL - Stop saving regs for the function 405 * MAKE_NOP - Stop tracing the function 406 */ 407 enum { 408 FTRACE_UPDATE_IGNORE, 409 FTRACE_UPDATE_MAKE_CALL, 410 FTRACE_UPDATE_MODIFY_CALL, 411 FTRACE_UPDATE_MAKE_NOP, 412 }; 413 414 enum { 415 FTRACE_ITER_FILTER = (1 << 0), 416 FTRACE_ITER_NOTRACE = (1 << 1), 417 FTRACE_ITER_PRINTALL = (1 << 2), 418 FTRACE_ITER_DO_HASH = (1 << 3), 419 FTRACE_ITER_HASH = (1 << 4), 420 FTRACE_ITER_ENABLED = (1 << 5), 421 }; 422 423 void arch_ftrace_update_code(int command); 424 425 struct ftrace_rec_iter; 426 427 struct ftrace_rec_iter *ftrace_rec_iter_start(void); 428 struct ftrace_rec_iter *ftrace_rec_iter_next(struct ftrace_rec_iter *iter); 429 struct dyn_ftrace *ftrace_rec_iter_record(struct ftrace_rec_iter *iter); 430 431 #define for_ftrace_rec_iter(iter) \ 432 for (iter = ftrace_rec_iter_start(); \ 433 iter; \ 434 iter = ftrace_rec_iter_next(iter)) 435 436 437 int ftrace_update_record(struct dyn_ftrace *rec, int enable); 438 int ftrace_test_record(struct dyn_ftrace *rec, int enable); 439 void ftrace_run_stop_machine(int command); 440 unsigned long ftrace_location(unsigned long ip); 441 unsigned long ftrace_get_addr_new(struct dyn_ftrace *rec); 442 unsigned long ftrace_get_addr_curr(struct dyn_ftrace *rec); 443 444 extern ftrace_func_t ftrace_trace_function; 445 446 int ftrace_regex_open(struct ftrace_ops *ops, int flag, 447 struct inode *inode, struct file *file); 448 ssize_t ftrace_filter_write(struct file *file, const char __user *ubuf, 449 size_t cnt, loff_t *ppos); 450 ssize_t ftrace_notrace_write(struct file *file, const char __user *ubuf, 451 size_t cnt, loff_t *ppos); 452 int ftrace_regex_release(struct inode *inode, struct file *file); 453 454 void __init 455 ftrace_set_early_filter(struct ftrace_ops *ops, char *buf, int enable); 456 457 /* defined in arch */ 458 extern int ftrace_ip_converted(unsigned long ip); 459 extern int ftrace_dyn_arch_init(void); 460 extern void ftrace_replace_code(int enable); 461 extern int ftrace_update_ftrace_func(ftrace_func_t func); 462 extern void ftrace_caller(void); 463 extern void ftrace_regs_caller(void); 464 extern void ftrace_call(void); 465 extern void ftrace_regs_call(void); 466 extern void mcount_call(void); 467 468 void ftrace_modify_all_code(int command); 469 470 #ifndef FTRACE_ADDR 471 #define FTRACE_ADDR ((unsigned long)ftrace_caller) 472 #endif 473 474 #ifndef FTRACE_GRAPH_ADDR 475 #define FTRACE_GRAPH_ADDR ((unsigned long)ftrace_graph_caller) 476 #endif 477 478 #ifndef FTRACE_REGS_ADDR 479 #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS 480 # define FTRACE_REGS_ADDR ((unsigned long)ftrace_regs_caller) 481 #else 482 # define FTRACE_REGS_ADDR FTRACE_ADDR 483 #endif 484 #endif 485 486 /* 487 * If an arch would like functions that are only traced 488 * by the function graph tracer to jump directly to its own 489 * trampoline, then they can define FTRACE_GRAPH_TRAMP_ADDR 490 * to be that address to jump to. 491 */ 492 #ifndef FTRACE_GRAPH_TRAMP_ADDR 493 #define FTRACE_GRAPH_TRAMP_ADDR ((unsigned long) 0) 494 #endif 495 496 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 497 extern void ftrace_graph_caller(void); 498 extern int ftrace_enable_ftrace_graph_caller(void); 499 extern int ftrace_disable_ftrace_graph_caller(void); 500 #else 501 static inline int ftrace_enable_ftrace_graph_caller(void) { return 0; } 502 static inline int ftrace_disable_ftrace_graph_caller(void) { return 0; } 503 #endif 504 505 /** 506 * ftrace_make_nop - convert code into nop 507 * @mod: module structure if called by module load initialization 508 * @rec: the mcount call site record 509 * @addr: the address that the call site should be calling 510 * 511 * This is a very sensitive operation and great care needs 512 * to be taken by the arch. The operation should carefully 513 * read the location, check to see if what is read is indeed 514 * what we expect it to be, and then on success of the compare, 515 * it should write to the location. 516 * 517 * The code segment at @rec->ip should be a caller to @addr 518 * 519 * Return must be: 520 * 0 on success 521 * -EFAULT on error reading the location 522 * -EINVAL on a failed compare of the contents 523 * -EPERM on error writing to the location 524 * Any other value will be considered a failure. 525 */ 526 extern int ftrace_make_nop(struct module *mod, 527 struct dyn_ftrace *rec, unsigned long addr); 528 529 /** 530 * ftrace_make_call - convert a nop call site into a call to addr 531 * @rec: the mcount call site record 532 * @addr: the address that the call site should call 533 * 534 * This is a very sensitive operation and great care needs 535 * to be taken by the arch. The operation should carefully 536 * read the location, check to see if what is read is indeed 537 * what we expect it to be, and then on success of the compare, 538 * it should write to the location. 539 * 540 * The code segment at @rec->ip should be a nop 541 * 542 * Return must be: 543 * 0 on success 544 * -EFAULT on error reading the location 545 * -EINVAL on a failed compare of the contents 546 * -EPERM on error writing to the location 547 * Any other value will be considered a failure. 548 */ 549 extern int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr); 550 551 #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS 552 /** 553 * ftrace_modify_call - convert from one addr to another (no nop) 554 * @rec: the mcount call site record 555 * @old_addr: the address expected to be currently called to 556 * @addr: the address to change to 557 * 558 * This is a very sensitive operation and great care needs 559 * to be taken by the arch. The operation should carefully 560 * read the location, check to see if what is read is indeed 561 * what we expect it to be, and then on success of the compare, 562 * it should write to the location. 563 * 564 * The code segment at @rec->ip should be a caller to @old_addr 565 * 566 * Return must be: 567 * 0 on success 568 * -EFAULT on error reading the location 569 * -EINVAL on a failed compare of the contents 570 * -EPERM on error writing to the location 571 * Any other value will be considered a failure. 572 */ 573 extern int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr, 574 unsigned long addr); 575 #else 576 /* Should never be called */ 577 static inline int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr, 578 unsigned long addr) 579 { 580 return -EINVAL; 581 } 582 #endif 583 584 /* May be defined in arch */ 585 extern int ftrace_arch_read_dyn_info(char *buf, int size); 586 587 extern int skip_trace(unsigned long ip); 588 extern void ftrace_module_init(struct module *mod); 589 590 extern void ftrace_disable_daemon(void); 591 extern void ftrace_enable_daemon(void); 592 #else /* CONFIG_DYNAMIC_FTRACE */ 593 static inline int skip_trace(unsigned long ip) { return 0; } 594 static inline int ftrace_force_update(void) { return 0; } 595 static inline void ftrace_disable_daemon(void) { } 596 static inline void ftrace_enable_daemon(void) { } 597 static inline void ftrace_release_mod(struct module *mod) {} 598 static inline void ftrace_module_init(struct module *mod) {} 599 static inline __init int register_ftrace_command(struct ftrace_func_command *cmd) 600 { 601 return -EINVAL; 602 } 603 static inline __init int unregister_ftrace_command(char *cmd_name) 604 { 605 return -EINVAL; 606 } 607 static inline int ftrace_text_reserved(const void *start, const void *end) 608 { 609 return 0; 610 } 611 static inline unsigned long ftrace_location(unsigned long ip) 612 { 613 return 0; 614 } 615 616 /* 617 * Again users of functions that have ftrace_ops may not 618 * have them defined when ftrace is not enabled, but these 619 * functions may still be called. Use a macro instead of inline. 620 */ 621 #define ftrace_regex_open(ops, flag, inod, file) ({ -ENODEV; }) 622 #define ftrace_set_early_filter(ops, buf, enable) do { } while (0) 623 #define ftrace_set_filter_ip(ops, ip, remove, reset) ({ -ENODEV; }) 624 #define ftrace_set_filter(ops, buf, len, reset) ({ -ENODEV; }) 625 #define ftrace_set_notrace(ops, buf, len, reset) ({ -ENODEV; }) 626 #define ftrace_free_filter(ops) do { } while (0) 627 628 static inline ssize_t ftrace_filter_write(struct file *file, const char __user *ubuf, 629 size_t cnt, loff_t *ppos) { return -ENODEV; } 630 static inline ssize_t ftrace_notrace_write(struct file *file, const char __user *ubuf, 631 size_t cnt, loff_t *ppos) { return -ENODEV; } 632 static inline int 633 ftrace_regex_release(struct inode *inode, struct file *file) { return -ENODEV; } 634 635 static inline bool is_ftrace_trampoline(unsigned long addr) 636 { 637 return false; 638 } 639 #endif /* CONFIG_DYNAMIC_FTRACE */ 640 641 /* totally disable ftrace - can not re-enable after this */ 642 void ftrace_kill(void); 643 644 static inline void tracer_disable(void) 645 { 646 #ifdef CONFIG_FUNCTION_TRACER 647 ftrace_enabled = 0; 648 #endif 649 } 650 651 /* 652 * Ftrace disable/restore without lock. Some synchronization mechanism 653 * must be used to prevent ftrace_enabled to be changed between 654 * disable/restore. 655 */ 656 static inline int __ftrace_enabled_save(void) 657 { 658 #ifdef CONFIG_FUNCTION_TRACER 659 int saved_ftrace_enabled = ftrace_enabled; 660 ftrace_enabled = 0; 661 return saved_ftrace_enabled; 662 #else 663 return 0; 664 #endif 665 } 666 667 static inline void __ftrace_enabled_restore(int enabled) 668 { 669 #ifdef CONFIG_FUNCTION_TRACER 670 ftrace_enabled = enabled; 671 #endif 672 } 673 674 /* All archs should have this, but we define it for consistency */ 675 #ifndef ftrace_return_address0 676 # define ftrace_return_address0 __builtin_return_address(0) 677 #endif 678 679 /* Archs may use other ways for ADDR1 and beyond */ 680 #ifndef ftrace_return_address 681 # ifdef CONFIG_FRAME_POINTER 682 # define ftrace_return_address(n) __builtin_return_address(n) 683 # else 684 # define ftrace_return_address(n) 0UL 685 # endif 686 #endif 687 688 #define CALLER_ADDR0 ((unsigned long)ftrace_return_address0) 689 #define CALLER_ADDR1 ((unsigned long)ftrace_return_address(1)) 690 #define CALLER_ADDR2 ((unsigned long)ftrace_return_address(2)) 691 #define CALLER_ADDR3 ((unsigned long)ftrace_return_address(3)) 692 #define CALLER_ADDR4 ((unsigned long)ftrace_return_address(4)) 693 #define CALLER_ADDR5 ((unsigned long)ftrace_return_address(5)) 694 #define CALLER_ADDR6 ((unsigned long)ftrace_return_address(6)) 695 696 #ifdef CONFIG_IRQSOFF_TRACER 697 extern void time_hardirqs_on(unsigned long a0, unsigned long a1); 698 extern void time_hardirqs_off(unsigned long a0, unsigned long a1); 699 #else 700 static inline void time_hardirqs_on(unsigned long a0, unsigned long a1) { } 701 static inline void time_hardirqs_off(unsigned long a0, unsigned long a1) { } 702 #endif 703 704 #ifdef CONFIG_PREEMPT_TRACER 705 extern void trace_preempt_on(unsigned long a0, unsigned long a1); 706 extern void trace_preempt_off(unsigned long a0, unsigned long a1); 707 #else 708 /* 709 * Use defines instead of static inlines because some arches will make code out 710 * of the CALLER_ADDR, when we really want these to be a real nop. 711 */ 712 # define trace_preempt_on(a0, a1) do { } while (0) 713 # define trace_preempt_off(a0, a1) do { } while (0) 714 #endif 715 716 #ifdef CONFIG_FTRACE_MCOUNT_RECORD 717 extern void ftrace_init(void); 718 #else 719 static inline void ftrace_init(void) { } 720 #endif 721 722 /* 723 * Structure that defines an entry function trace. 724 */ 725 struct ftrace_graph_ent { 726 unsigned long func; /* Current function */ 727 int depth; 728 }; 729 730 /* 731 * Structure that defines a return function trace. 732 */ 733 struct ftrace_graph_ret { 734 unsigned long func; /* Current function */ 735 unsigned long long calltime; 736 unsigned long long rettime; 737 /* Number of functions that overran the depth limit for current task */ 738 unsigned long overrun; 739 int depth; 740 }; 741 742 /* Type of the callback handlers for tracing function graph*/ 743 typedef void (*trace_func_graph_ret_t)(struct ftrace_graph_ret *); /* return */ 744 typedef int (*trace_func_graph_ent_t)(struct ftrace_graph_ent *); /* entry */ 745 746 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 747 748 /* for init task */ 749 #define INIT_FTRACE_GRAPH .ret_stack = NULL, 750 751 /* 752 * Stack of return addresses for functions 753 * of a thread. 754 * Used in struct thread_info 755 */ 756 struct ftrace_ret_stack { 757 unsigned long ret; 758 unsigned long func; 759 unsigned long long calltime; 760 unsigned long long subtime; 761 unsigned long fp; 762 }; 763 764 /* 765 * Primary handler of a function return. 766 * It relays on ftrace_return_to_handler. 767 * Defined in entry_32/64.S 768 */ 769 extern void return_to_handler(void); 770 771 extern int 772 ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth, 773 unsigned long frame_pointer); 774 775 /* 776 * Sometimes we don't want to trace a function with the function 777 * graph tracer but we want them to keep traced by the usual function 778 * tracer if the function graph tracer is not configured. 779 */ 780 #define __notrace_funcgraph notrace 781 782 /* 783 * We want to which function is an entrypoint of a hardirq. 784 * That will help us to put a signal on output. 785 */ 786 #define __irq_entry __attribute__((__section__(".irqentry.text"))) 787 788 /* Limits of hardirq entrypoints */ 789 extern char __irqentry_text_start[]; 790 extern char __irqentry_text_end[]; 791 792 #define FTRACE_NOTRACE_DEPTH 65536 793 #define FTRACE_RETFUNC_DEPTH 50 794 #define FTRACE_RETSTACK_ALLOC_SIZE 32 795 extern int register_ftrace_graph(trace_func_graph_ret_t retfunc, 796 trace_func_graph_ent_t entryfunc); 797 798 extern bool ftrace_graph_is_dead(void); 799 extern void ftrace_graph_stop(void); 800 801 /* The current handlers in use */ 802 extern trace_func_graph_ret_t ftrace_graph_return; 803 extern trace_func_graph_ent_t ftrace_graph_entry; 804 805 extern void unregister_ftrace_graph(void); 806 807 extern void ftrace_graph_init_task(struct task_struct *t); 808 extern void ftrace_graph_exit_task(struct task_struct *t); 809 extern void ftrace_graph_init_idle_task(struct task_struct *t, int cpu); 810 811 static inline int task_curr_ret_stack(struct task_struct *t) 812 { 813 return t->curr_ret_stack; 814 } 815 816 static inline void pause_graph_tracing(void) 817 { 818 atomic_inc(¤t->tracing_graph_pause); 819 } 820 821 static inline void unpause_graph_tracing(void) 822 { 823 atomic_dec(¤t->tracing_graph_pause); 824 } 825 #else /* !CONFIG_FUNCTION_GRAPH_TRACER */ 826 827 #define __notrace_funcgraph 828 #define __irq_entry 829 #define INIT_FTRACE_GRAPH 830 831 static inline void ftrace_graph_init_task(struct task_struct *t) { } 832 static inline void ftrace_graph_exit_task(struct task_struct *t) { } 833 static inline void ftrace_graph_init_idle_task(struct task_struct *t, int cpu) { } 834 835 static inline int register_ftrace_graph(trace_func_graph_ret_t retfunc, 836 trace_func_graph_ent_t entryfunc) 837 { 838 return -1; 839 } 840 static inline void unregister_ftrace_graph(void) { } 841 842 static inline int task_curr_ret_stack(struct task_struct *tsk) 843 { 844 return -1; 845 } 846 847 static inline void pause_graph_tracing(void) { } 848 static inline void unpause_graph_tracing(void) { } 849 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ 850 851 #ifdef CONFIG_TRACING 852 853 /* flags for current->trace */ 854 enum { 855 TSK_TRACE_FL_TRACE_BIT = 0, 856 TSK_TRACE_FL_GRAPH_BIT = 1, 857 }; 858 enum { 859 TSK_TRACE_FL_TRACE = 1 << TSK_TRACE_FL_TRACE_BIT, 860 TSK_TRACE_FL_GRAPH = 1 << TSK_TRACE_FL_GRAPH_BIT, 861 }; 862 863 static inline void set_tsk_trace_trace(struct task_struct *tsk) 864 { 865 set_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace); 866 } 867 868 static inline void clear_tsk_trace_trace(struct task_struct *tsk) 869 { 870 clear_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace); 871 } 872 873 static inline int test_tsk_trace_trace(struct task_struct *tsk) 874 { 875 return tsk->trace & TSK_TRACE_FL_TRACE; 876 } 877 878 static inline void set_tsk_trace_graph(struct task_struct *tsk) 879 { 880 set_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace); 881 } 882 883 static inline void clear_tsk_trace_graph(struct task_struct *tsk) 884 { 885 clear_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace); 886 } 887 888 static inline int test_tsk_trace_graph(struct task_struct *tsk) 889 { 890 return tsk->trace & TSK_TRACE_FL_GRAPH; 891 } 892 893 enum ftrace_dump_mode; 894 895 extern enum ftrace_dump_mode ftrace_dump_on_oops; 896 extern int tracepoint_printk; 897 898 extern void disable_trace_on_warning(void); 899 extern int __disable_trace_on_warning; 900 901 #ifdef CONFIG_PREEMPT 902 #define INIT_TRACE_RECURSION .trace_recursion = 0, 903 #endif 904 905 #else /* CONFIG_TRACING */ 906 static inline void disable_trace_on_warning(void) { } 907 #endif /* CONFIG_TRACING */ 908 909 #ifndef INIT_TRACE_RECURSION 910 #define INIT_TRACE_RECURSION 911 #endif 912 913 #ifdef CONFIG_FTRACE_SYSCALLS 914 915 unsigned long arch_syscall_addr(int nr); 916 917 #endif /* CONFIG_FTRACE_SYSCALLS */ 918 919 #endif /* _LINUX_FTRACE_H */ 920