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 !defined(CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST) || \ 37 !ARCH_SUPPORTS_FTRACE_OPS 38 # define FTRACE_FORCE_LIST_FUNC 1 39 #else 40 # define FTRACE_FORCE_LIST_FUNC 0 41 #endif 42 43 44 struct module; 45 struct ftrace_hash; 46 47 #ifdef CONFIG_FUNCTION_TRACER 48 49 extern int ftrace_enabled; 50 extern int 51 ftrace_enable_sysctl(struct ctl_table *table, int write, 52 void __user *buffer, size_t *lenp, 53 loff_t *ppos); 54 55 struct ftrace_ops; 56 57 typedef void (*ftrace_func_t)(unsigned long ip, unsigned long parent_ip, 58 struct ftrace_ops *op, struct pt_regs *regs); 59 60 /* 61 * FTRACE_OPS_FL_* bits denote the state of ftrace_ops struct and are 62 * set in the flags member. 63 * 64 * ENABLED - set/unset when ftrace_ops is registered/unregistered 65 * GLOBAL - set manualy by ftrace_ops user to denote the ftrace_ops 66 * is part of the global tracers sharing the same filter 67 * via set_ftrace_* debugfs files. 68 * DYNAMIC - set when ftrace_ops is registered to denote dynamically 69 * allocated ftrace_ops which need special care 70 * CONTROL - set manualy by ftrace_ops user to denote the ftrace_ops 71 * could be controled by following calls: 72 * ftrace_function_local_enable 73 * ftrace_function_local_disable 74 * SAVE_REGS - The ftrace_ops wants regs saved at each function called 75 * and passed to the callback. If this flag is set, but the 76 * architecture does not support passing regs 77 * (CONFIG_DYNAMIC_FTRACE_WITH_REGS is not defined), then the 78 * ftrace_ops will fail to register, unless the next flag 79 * is set. 80 * SAVE_REGS_IF_SUPPORTED - This is the same as SAVE_REGS, but if the 81 * handler can handle an arch that does not save regs 82 * (the handler tests if regs == NULL), then it can set 83 * this flag instead. It will not fail registering the ftrace_ops 84 * but, the regs field will be NULL if the arch does not support 85 * passing regs to the handler. 86 * Note, if this flag is set, the SAVE_REGS flag will automatically 87 * get set upon registering the ftrace_ops, if the arch supports it. 88 * RECURSION_SAFE - The ftrace_ops can set this to tell the ftrace infrastructure 89 * that the call back has its own recursion protection. If it does 90 * not set this, then the ftrace infrastructure will add recursion 91 * protection for the caller. 92 * STUB - The ftrace_ops is just a place holder. 93 * INITIALIZED - The ftrace_ops has already been initialized (first use time 94 * register_ftrace_function() is called, it will initialized the ops) 95 */ 96 enum { 97 FTRACE_OPS_FL_ENABLED = 1 << 0, 98 FTRACE_OPS_FL_GLOBAL = 1 << 1, 99 FTRACE_OPS_FL_DYNAMIC = 1 << 2, 100 FTRACE_OPS_FL_CONTROL = 1 << 3, 101 FTRACE_OPS_FL_SAVE_REGS = 1 << 4, 102 FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED = 1 << 5, 103 FTRACE_OPS_FL_RECURSION_SAFE = 1 << 6, 104 FTRACE_OPS_FL_STUB = 1 << 7, 105 FTRACE_OPS_FL_INITIALIZED = 1 << 8, 106 }; 107 108 struct ftrace_ops { 109 ftrace_func_t func; 110 struct ftrace_ops *next; 111 unsigned long flags; 112 int __percpu *disabled; 113 #ifdef CONFIG_DYNAMIC_FTRACE 114 struct ftrace_hash *notrace_hash; 115 struct ftrace_hash *filter_hash; 116 struct mutex regex_lock; 117 #endif 118 }; 119 120 extern int function_trace_stop; 121 122 /* 123 * Type of the current tracing. 124 */ 125 enum ftrace_tracing_type_t { 126 FTRACE_TYPE_ENTER = 0, /* Hook the call of the function */ 127 FTRACE_TYPE_RETURN, /* Hook the return of the function */ 128 }; 129 130 /* Current tracing type, default is FTRACE_TYPE_ENTER */ 131 extern enum ftrace_tracing_type_t ftrace_tracing_type; 132 133 /** 134 * ftrace_stop - stop function tracer. 135 * 136 * A quick way to stop the function tracer. Note this an on off switch, 137 * it is not something that is recursive like preempt_disable. 138 * This does not disable the calling of mcount, it only stops the 139 * calling of functions from mcount. 140 */ 141 static inline void ftrace_stop(void) 142 { 143 function_trace_stop = 1; 144 } 145 146 /** 147 * ftrace_start - start the function tracer. 148 * 149 * This function is the inverse of ftrace_stop. This does not enable 150 * the function tracing if the function tracer is disabled. This only 151 * sets the function tracer flag to continue calling the functions 152 * from mcount. 153 */ 154 static inline void ftrace_start(void) 155 { 156 function_trace_stop = 0; 157 } 158 159 /* 160 * The ftrace_ops must be a static and should also 161 * be read_mostly. These functions do modify read_mostly variables 162 * so use them sparely. Never free an ftrace_op or modify the 163 * next pointer after it has been registered. Even after unregistering 164 * it, the next pointer may still be used internally. 165 */ 166 int register_ftrace_function(struct ftrace_ops *ops); 167 int unregister_ftrace_function(struct ftrace_ops *ops); 168 void clear_ftrace_function(void); 169 170 /** 171 * ftrace_function_local_enable - enable controlled ftrace_ops on current cpu 172 * 173 * This function enables tracing on current cpu by decreasing 174 * the per cpu control variable. 175 * It must be called with preemption disabled and only on ftrace_ops 176 * registered with FTRACE_OPS_FL_CONTROL. If called without preemption 177 * disabled, this_cpu_ptr will complain when CONFIG_DEBUG_PREEMPT is enabled. 178 */ 179 static inline void ftrace_function_local_enable(struct ftrace_ops *ops) 180 { 181 if (WARN_ON_ONCE(!(ops->flags & FTRACE_OPS_FL_CONTROL))) 182 return; 183 184 (*this_cpu_ptr(ops->disabled))--; 185 } 186 187 /** 188 * ftrace_function_local_disable - enable controlled ftrace_ops on current cpu 189 * 190 * This function enables tracing on current cpu by decreasing 191 * the per cpu control variable. 192 * It must be called with preemption disabled and only on ftrace_ops 193 * registered with FTRACE_OPS_FL_CONTROL. If called without preemption 194 * disabled, this_cpu_ptr will complain when CONFIG_DEBUG_PREEMPT is enabled. 195 */ 196 static inline void ftrace_function_local_disable(struct ftrace_ops *ops) 197 { 198 if (WARN_ON_ONCE(!(ops->flags & FTRACE_OPS_FL_CONTROL))) 199 return; 200 201 (*this_cpu_ptr(ops->disabled))++; 202 } 203 204 /** 205 * ftrace_function_local_disabled - returns ftrace_ops disabled value 206 * on current cpu 207 * 208 * This function returns value of ftrace_ops::disabled on current cpu. 209 * It must be called with preemption disabled and only on ftrace_ops 210 * registered with FTRACE_OPS_FL_CONTROL. If called without preemption 211 * disabled, this_cpu_ptr will complain when CONFIG_DEBUG_PREEMPT is enabled. 212 */ 213 static inline int ftrace_function_local_disabled(struct ftrace_ops *ops) 214 { 215 WARN_ON_ONCE(!(ops->flags & FTRACE_OPS_FL_CONTROL)); 216 return *this_cpu_ptr(ops->disabled); 217 } 218 219 extern void ftrace_stub(unsigned long a0, unsigned long a1, 220 struct ftrace_ops *op, struct pt_regs *regs); 221 222 #else /* !CONFIG_FUNCTION_TRACER */ 223 /* 224 * (un)register_ftrace_function must be a macro since the ops parameter 225 * must not be evaluated. 226 */ 227 #define register_ftrace_function(ops) ({ 0; }) 228 #define unregister_ftrace_function(ops) ({ 0; }) 229 static inline int ftrace_nr_registered_ops(void) 230 { 231 return 0; 232 } 233 static inline void clear_ftrace_function(void) { } 234 static inline void ftrace_kill(void) { } 235 static inline void ftrace_stop(void) { } 236 static inline void ftrace_start(void) { } 237 #endif /* CONFIG_FUNCTION_TRACER */ 238 239 #ifdef CONFIG_STACK_TRACER 240 extern int stack_tracer_enabled; 241 int 242 stack_trace_sysctl(struct ctl_table *table, int write, 243 void __user *buffer, size_t *lenp, 244 loff_t *ppos); 245 #endif 246 247 struct ftrace_func_command { 248 struct list_head list; 249 char *name; 250 int (*func)(struct ftrace_hash *hash, 251 char *func, char *cmd, 252 char *params, int enable); 253 }; 254 255 #ifdef CONFIG_DYNAMIC_FTRACE 256 257 int ftrace_arch_code_modify_prepare(void); 258 int ftrace_arch_code_modify_post_process(void); 259 260 void ftrace_bug(int err, unsigned long ip); 261 262 struct seq_file; 263 264 struct ftrace_probe_ops { 265 void (*func)(unsigned long ip, 266 unsigned long parent_ip, 267 void **data); 268 int (*init)(struct ftrace_probe_ops *ops, 269 unsigned long ip, void **data); 270 void (*free)(struct ftrace_probe_ops *ops, 271 unsigned long ip, void **data); 272 int (*print)(struct seq_file *m, 273 unsigned long ip, 274 struct ftrace_probe_ops *ops, 275 void *data); 276 }; 277 278 extern int 279 register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, 280 void *data); 281 extern void 282 unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, 283 void *data); 284 extern void 285 unregister_ftrace_function_probe_func(char *glob, struct ftrace_probe_ops *ops); 286 extern void unregister_ftrace_function_probe_all(char *glob); 287 288 extern int ftrace_text_reserved(void *start, void *end); 289 290 extern int ftrace_nr_registered_ops(void); 291 292 /* 293 * The dyn_ftrace record's flags field is split into two parts. 294 * the first part which is '0-FTRACE_REF_MAX' is a counter of 295 * the number of callbacks that have registered the function that 296 * the dyn_ftrace descriptor represents. 297 * 298 * The second part is a mask: 299 * ENABLED - the function is being traced 300 * REGS - the record wants the function to save regs 301 * REGS_EN - the function is set up to save regs. 302 * 303 * When a new ftrace_ops is registered and wants a function to save 304 * pt_regs, the rec->flag REGS is set. When the function has been 305 * set up to save regs, the REG_EN flag is set. Once a function 306 * starts saving regs it will do so until all ftrace_ops are removed 307 * from tracing that function. 308 */ 309 enum { 310 FTRACE_FL_ENABLED = (1UL << 29), 311 FTRACE_FL_REGS = (1UL << 30), 312 FTRACE_FL_REGS_EN = (1UL << 31) 313 }; 314 315 #define FTRACE_FL_MASK (0x7UL << 29) 316 #define FTRACE_REF_MAX ((1UL << 29) - 1) 317 318 struct dyn_ftrace { 319 union { 320 unsigned long ip; /* address of mcount call-site */ 321 struct dyn_ftrace *freelist; 322 }; 323 unsigned long flags; 324 struct dyn_arch_ftrace arch; 325 }; 326 327 int ftrace_force_update(void); 328 int ftrace_set_filter_ip(struct ftrace_ops *ops, unsigned long ip, 329 int remove, int reset); 330 int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf, 331 int len, int reset); 332 int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf, 333 int len, int reset); 334 void ftrace_set_global_filter(unsigned char *buf, int len, int reset); 335 void ftrace_set_global_notrace(unsigned char *buf, int len, int reset); 336 void ftrace_free_filter(struct ftrace_ops *ops); 337 338 int register_ftrace_command(struct ftrace_func_command *cmd); 339 int unregister_ftrace_command(struct ftrace_func_command *cmd); 340 341 enum { 342 FTRACE_UPDATE_CALLS = (1 << 0), 343 FTRACE_DISABLE_CALLS = (1 << 1), 344 FTRACE_UPDATE_TRACE_FUNC = (1 << 2), 345 FTRACE_START_FUNC_RET = (1 << 3), 346 FTRACE_STOP_FUNC_RET = (1 << 4), 347 }; 348 349 /* 350 * The FTRACE_UPDATE_* enum is used to pass information back 351 * from the ftrace_update_record() and ftrace_test_record() 352 * functions. These are called by the code update routines 353 * to find out what is to be done for a given function. 354 * 355 * IGNORE - The function is already what we want it to be 356 * MAKE_CALL - Start tracing the function 357 * MODIFY_CALL - Stop saving regs for the function 358 * MODIFY_CALL_REGS - Start saving regs for the function 359 * MAKE_NOP - Stop tracing the function 360 */ 361 enum { 362 FTRACE_UPDATE_IGNORE, 363 FTRACE_UPDATE_MAKE_CALL, 364 FTRACE_UPDATE_MODIFY_CALL, 365 FTRACE_UPDATE_MODIFY_CALL_REGS, 366 FTRACE_UPDATE_MAKE_NOP, 367 }; 368 369 enum { 370 FTRACE_ITER_FILTER = (1 << 0), 371 FTRACE_ITER_NOTRACE = (1 << 1), 372 FTRACE_ITER_PRINTALL = (1 << 2), 373 FTRACE_ITER_DO_HASH = (1 << 3), 374 FTRACE_ITER_HASH = (1 << 4), 375 FTRACE_ITER_ENABLED = (1 << 5), 376 }; 377 378 void arch_ftrace_update_code(int command); 379 380 struct ftrace_rec_iter; 381 382 struct ftrace_rec_iter *ftrace_rec_iter_start(void); 383 struct ftrace_rec_iter *ftrace_rec_iter_next(struct ftrace_rec_iter *iter); 384 struct dyn_ftrace *ftrace_rec_iter_record(struct ftrace_rec_iter *iter); 385 386 #define for_ftrace_rec_iter(iter) \ 387 for (iter = ftrace_rec_iter_start(); \ 388 iter; \ 389 iter = ftrace_rec_iter_next(iter)) 390 391 392 int ftrace_update_record(struct dyn_ftrace *rec, int enable); 393 int ftrace_test_record(struct dyn_ftrace *rec, int enable); 394 void ftrace_run_stop_machine(int command); 395 unsigned long ftrace_location(unsigned long ip); 396 397 extern ftrace_func_t ftrace_trace_function; 398 399 int ftrace_regex_open(struct ftrace_ops *ops, int flag, 400 struct inode *inode, struct file *file); 401 ssize_t ftrace_filter_write(struct file *file, const char __user *ubuf, 402 size_t cnt, loff_t *ppos); 403 ssize_t ftrace_notrace_write(struct file *file, const char __user *ubuf, 404 size_t cnt, loff_t *ppos); 405 int ftrace_regex_release(struct inode *inode, struct file *file); 406 407 void __init 408 ftrace_set_early_filter(struct ftrace_ops *ops, char *buf, int enable); 409 410 /* defined in arch */ 411 extern int ftrace_ip_converted(unsigned long ip); 412 extern int ftrace_dyn_arch_init(void *data); 413 extern void ftrace_replace_code(int enable); 414 extern int ftrace_update_ftrace_func(ftrace_func_t func); 415 extern void ftrace_caller(void); 416 extern void ftrace_regs_caller(void); 417 extern void ftrace_call(void); 418 extern void ftrace_regs_call(void); 419 extern void mcount_call(void); 420 421 void ftrace_modify_all_code(int command); 422 423 #ifndef FTRACE_ADDR 424 #define FTRACE_ADDR ((unsigned long)ftrace_caller) 425 #endif 426 427 #ifndef FTRACE_REGS_ADDR 428 #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS 429 # define FTRACE_REGS_ADDR ((unsigned long)ftrace_regs_caller) 430 #else 431 # define FTRACE_REGS_ADDR FTRACE_ADDR 432 #endif 433 #endif 434 435 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 436 extern void ftrace_graph_caller(void); 437 extern int ftrace_enable_ftrace_graph_caller(void); 438 extern int ftrace_disable_ftrace_graph_caller(void); 439 #else 440 static inline int ftrace_enable_ftrace_graph_caller(void) { return 0; } 441 static inline int ftrace_disable_ftrace_graph_caller(void) { return 0; } 442 #endif 443 444 /** 445 * ftrace_make_nop - convert code into nop 446 * @mod: module structure if called by module load initialization 447 * @rec: the mcount call site record 448 * @addr: the address that the call site should be calling 449 * 450 * This is a very sensitive operation and great care needs 451 * to be taken by the arch. The operation should carefully 452 * read the location, check to see if what is read is indeed 453 * what we expect it to be, and then on success of the compare, 454 * it should write to the location. 455 * 456 * The code segment at @rec->ip should be a caller to @addr 457 * 458 * Return must be: 459 * 0 on success 460 * -EFAULT on error reading the location 461 * -EINVAL on a failed compare of the contents 462 * -EPERM on error writing to the location 463 * Any other value will be considered a failure. 464 */ 465 extern int ftrace_make_nop(struct module *mod, 466 struct dyn_ftrace *rec, unsigned long addr); 467 468 /** 469 * ftrace_make_call - convert a nop call site into a call to addr 470 * @rec: the mcount call site record 471 * @addr: the address that the call site should call 472 * 473 * This is a very sensitive operation and great care needs 474 * to be taken by the arch. The operation should carefully 475 * read the location, check to see if what is read is indeed 476 * what we expect it to be, and then on success of the compare, 477 * it should write to the location. 478 * 479 * The code segment at @rec->ip should be a nop 480 * 481 * Return must be: 482 * 0 on success 483 * -EFAULT on error reading the location 484 * -EINVAL on a failed compare of the contents 485 * -EPERM on error writing to the location 486 * Any other value will be considered a failure. 487 */ 488 extern int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr); 489 490 #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS 491 /** 492 * ftrace_modify_call - convert from one addr to another (no nop) 493 * @rec: the mcount call site record 494 * @old_addr: the address expected to be currently called to 495 * @addr: the address to change to 496 * 497 * This is a very sensitive operation and great care needs 498 * to be taken by the arch. The operation should carefully 499 * read the location, check to see if what is read is indeed 500 * what we expect it to be, and then on success of the compare, 501 * it should write to the location. 502 * 503 * The code segment at @rec->ip should be a caller to @old_addr 504 * 505 * Return must be: 506 * 0 on success 507 * -EFAULT on error reading the location 508 * -EINVAL on a failed compare of the contents 509 * -EPERM on error writing to the location 510 * Any other value will be considered a failure. 511 */ 512 extern int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr, 513 unsigned long addr); 514 #else 515 /* Should never be called */ 516 static inline int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr, 517 unsigned long addr) 518 { 519 return -EINVAL; 520 } 521 #endif 522 523 /* May be defined in arch */ 524 extern int ftrace_arch_read_dyn_info(char *buf, int size); 525 526 extern int skip_trace(unsigned long ip); 527 528 extern void ftrace_disable_daemon(void); 529 extern void ftrace_enable_daemon(void); 530 #else /* CONFIG_DYNAMIC_FTRACE */ 531 static inline int skip_trace(unsigned long ip) { return 0; } 532 static inline int ftrace_force_update(void) { return 0; } 533 static inline void ftrace_disable_daemon(void) { } 534 static inline void ftrace_enable_daemon(void) { } 535 static inline void ftrace_release_mod(struct module *mod) {} 536 static inline int register_ftrace_command(struct ftrace_func_command *cmd) 537 { 538 return -EINVAL; 539 } 540 static inline int unregister_ftrace_command(char *cmd_name) 541 { 542 return -EINVAL; 543 } 544 static inline int ftrace_text_reserved(void *start, void *end) 545 { 546 return 0; 547 } 548 static inline unsigned long ftrace_location(unsigned long ip) 549 { 550 return 0; 551 } 552 553 /* 554 * Again users of functions that have ftrace_ops may not 555 * have them defined when ftrace is not enabled, but these 556 * functions may still be called. Use a macro instead of inline. 557 */ 558 #define ftrace_regex_open(ops, flag, inod, file) ({ -ENODEV; }) 559 #define ftrace_set_early_filter(ops, buf, enable) do { } while (0) 560 #define ftrace_set_filter_ip(ops, ip, remove, reset) ({ -ENODEV; }) 561 #define ftrace_set_filter(ops, buf, len, reset) ({ -ENODEV; }) 562 #define ftrace_set_notrace(ops, buf, len, reset) ({ -ENODEV; }) 563 #define ftrace_free_filter(ops) do { } while (0) 564 565 static inline ssize_t ftrace_filter_write(struct file *file, const char __user *ubuf, 566 size_t cnt, loff_t *ppos) { return -ENODEV; } 567 static inline ssize_t ftrace_notrace_write(struct file *file, const char __user *ubuf, 568 size_t cnt, loff_t *ppos) { return -ENODEV; } 569 static inline loff_t ftrace_regex_lseek(struct file *file, loff_t offset, int whence) 570 { 571 return -ENODEV; 572 } 573 static inline int 574 ftrace_regex_release(struct inode *inode, struct file *file) { return -ENODEV; } 575 #endif /* CONFIG_DYNAMIC_FTRACE */ 576 577 loff_t ftrace_filter_lseek(struct file *file, loff_t offset, int whence); 578 579 /* totally disable ftrace - can not re-enable after this */ 580 void ftrace_kill(void); 581 582 static inline void tracer_disable(void) 583 { 584 #ifdef CONFIG_FUNCTION_TRACER 585 ftrace_enabled = 0; 586 #endif 587 } 588 589 /* 590 * Ftrace disable/restore without lock. Some synchronization mechanism 591 * must be used to prevent ftrace_enabled to be changed between 592 * disable/restore. 593 */ 594 static inline int __ftrace_enabled_save(void) 595 { 596 #ifdef CONFIG_FUNCTION_TRACER 597 int saved_ftrace_enabled = ftrace_enabled; 598 ftrace_enabled = 0; 599 return saved_ftrace_enabled; 600 #else 601 return 0; 602 #endif 603 } 604 605 static inline void __ftrace_enabled_restore(int enabled) 606 { 607 #ifdef CONFIG_FUNCTION_TRACER 608 ftrace_enabled = enabled; 609 #endif 610 } 611 612 #ifndef HAVE_ARCH_CALLER_ADDR 613 # ifdef CONFIG_FRAME_POINTER 614 # define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0)) 615 # define CALLER_ADDR1 ((unsigned long)__builtin_return_address(1)) 616 # define CALLER_ADDR2 ((unsigned long)__builtin_return_address(2)) 617 # define CALLER_ADDR3 ((unsigned long)__builtin_return_address(3)) 618 # define CALLER_ADDR4 ((unsigned long)__builtin_return_address(4)) 619 # define CALLER_ADDR5 ((unsigned long)__builtin_return_address(5)) 620 # define CALLER_ADDR6 ((unsigned long)__builtin_return_address(6)) 621 # else 622 # define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0)) 623 # define CALLER_ADDR1 0UL 624 # define CALLER_ADDR2 0UL 625 # define CALLER_ADDR3 0UL 626 # define CALLER_ADDR4 0UL 627 # define CALLER_ADDR5 0UL 628 # define CALLER_ADDR6 0UL 629 # endif 630 #endif /* ifndef HAVE_ARCH_CALLER_ADDR */ 631 632 #ifdef CONFIG_IRQSOFF_TRACER 633 extern void time_hardirqs_on(unsigned long a0, unsigned long a1); 634 extern void time_hardirqs_off(unsigned long a0, unsigned long a1); 635 #else 636 static inline void time_hardirqs_on(unsigned long a0, unsigned long a1) { } 637 static inline void time_hardirqs_off(unsigned long a0, unsigned long a1) { } 638 #endif 639 640 #ifdef CONFIG_PREEMPT_TRACER 641 extern void trace_preempt_on(unsigned long a0, unsigned long a1); 642 extern void trace_preempt_off(unsigned long a0, unsigned long a1); 643 #else 644 /* 645 * Use defines instead of static inlines because some arches will make code out 646 * of the CALLER_ADDR, when we really want these to be a real nop. 647 */ 648 # define trace_preempt_on(a0, a1) do { } while (0) 649 # define trace_preempt_off(a0, a1) do { } while (0) 650 #endif 651 652 #ifdef CONFIG_FTRACE_MCOUNT_RECORD 653 extern void ftrace_init(void); 654 #else 655 static inline void ftrace_init(void) { } 656 #endif 657 658 /* 659 * Structure that defines an entry function trace. 660 */ 661 struct ftrace_graph_ent { 662 unsigned long func; /* Current function */ 663 int depth; 664 }; 665 666 /* 667 * Structure that defines a return function trace. 668 */ 669 struct ftrace_graph_ret { 670 unsigned long func; /* Current function */ 671 unsigned long long calltime; 672 unsigned long long rettime; 673 /* Number of functions that overran the depth limit for current task */ 674 unsigned long overrun; 675 int depth; 676 }; 677 678 /* Type of the callback handlers for tracing function graph*/ 679 typedef void (*trace_func_graph_ret_t)(struct ftrace_graph_ret *); /* return */ 680 typedef int (*trace_func_graph_ent_t)(struct ftrace_graph_ent *); /* entry */ 681 682 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 683 684 /* for init task */ 685 #define INIT_FTRACE_GRAPH .ret_stack = NULL, 686 687 /* 688 * Stack of return addresses for functions 689 * of a thread. 690 * Used in struct thread_info 691 */ 692 struct ftrace_ret_stack { 693 unsigned long ret; 694 unsigned long func; 695 unsigned long long calltime; 696 unsigned long long subtime; 697 unsigned long fp; 698 }; 699 700 /* 701 * Primary handler of a function return. 702 * It relays on ftrace_return_to_handler. 703 * Defined in entry_32/64.S 704 */ 705 extern void return_to_handler(void); 706 707 extern int 708 ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth, 709 unsigned long frame_pointer); 710 711 /* 712 * Sometimes we don't want to trace a function with the function 713 * graph tracer but we want them to keep traced by the usual function 714 * tracer if the function graph tracer is not configured. 715 */ 716 #define __notrace_funcgraph notrace 717 718 /* 719 * We want to which function is an entrypoint of a hardirq. 720 * That will help us to put a signal on output. 721 */ 722 #define __irq_entry __attribute__((__section__(".irqentry.text"))) 723 724 /* Limits of hardirq entrypoints */ 725 extern char __irqentry_text_start[]; 726 extern char __irqentry_text_end[]; 727 728 #define FTRACE_RETFUNC_DEPTH 50 729 #define FTRACE_RETSTACK_ALLOC_SIZE 32 730 extern int register_ftrace_graph(trace_func_graph_ret_t retfunc, 731 trace_func_graph_ent_t entryfunc); 732 733 extern void ftrace_graph_stop(void); 734 735 /* The current handlers in use */ 736 extern trace_func_graph_ret_t ftrace_graph_return; 737 extern trace_func_graph_ent_t ftrace_graph_entry; 738 739 extern void unregister_ftrace_graph(void); 740 741 extern void ftrace_graph_init_task(struct task_struct *t); 742 extern void ftrace_graph_exit_task(struct task_struct *t); 743 extern void ftrace_graph_init_idle_task(struct task_struct *t, int cpu); 744 745 static inline int task_curr_ret_stack(struct task_struct *t) 746 { 747 return t->curr_ret_stack; 748 } 749 750 static inline void pause_graph_tracing(void) 751 { 752 atomic_inc(¤t->tracing_graph_pause); 753 } 754 755 static inline void unpause_graph_tracing(void) 756 { 757 atomic_dec(¤t->tracing_graph_pause); 758 } 759 #else /* !CONFIG_FUNCTION_GRAPH_TRACER */ 760 761 #define __notrace_funcgraph 762 #define __irq_entry 763 #define INIT_FTRACE_GRAPH 764 765 static inline void ftrace_graph_init_task(struct task_struct *t) { } 766 static inline void ftrace_graph_exit_task(struct task_struct *t) { } 767 static inline void ftrace_graph_init_idle_task(struct task_struct *t, int cpu) { } 768 769 static inline int register_ftrace_graph(trace_func_graph_ret_t retfunc, 770 trace_func_graph_ent_t entryfunc) 771 { 772 return -1; 773 } 774 static inline void unregister_ftrace_graph(void) { } 775 776 static inline int task_curr_ret_stack(struct task_struct *tsk) 777 { 778 return -1; 779 } 780 781 static inline void pause_graph_tracing(void) { } 782 static inline void unpause_graph_tracing(void) { } 783 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ 784 785 #ifdef CONFIG_TRACING 786 787 /* flags for current->trace */ 788 enum { 789 TSK_TRACE_FL_TRACE_BIT = 0, 790 TSK_TRACE_FL_GRAPH_BIT = 1, 791 }; 792 enum { 793 TSK_TRACE_FL_TRACE = 1 << TSK_TRACE_FL_TRACE_BIT, 794 TSK_TRACE_FL_GRAPH = 1 << TSK_TRACE_FL_GRAPH_BIT, 795 }; 796 797 static inline void set_tsk_trace_trace(struct task_struct *tsk) 798 { 799 set_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace); 800 } 801 802 static inline void clear_tsk_trace_trace(struct task_struct *tsk) 803 { 804 clear_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace); 805 } 806 807 static inline int test_tsk_trace_trace(struct task_struct *tsk) 808 { 809 return tsk->trace & TSK_TRACE_FL_TRACE; 810 } 811 812 static inline void set_tsk_trace_graph(struct task_struct *tsk) 813 { 814 set_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace); 815 } 816 817 static inline void clear_tsk_trace_graph(struct task_struct *tsk) 818 { 819 clear_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace); 820 } 821 822 static inline int test_tsk_trace_graph(struct task_struct *tsk) 823 { 824 return tsk->trace & TSK_TRACE_FL_GRAPH; 825 } 826 827 enum ftrace_dump_mode; 828 829 extern enum ftrace_dump_mode ftrace_dump_on_oops; 830 831 #ifdef CONFIG_PREEMPT 832 #define INIT_TRACE_RECURSION .trace_recursion = 0, 833 #endif 834 835 #endif /* CONFIG_TRACING */ 836 837 #ifndef INIT_TRACE_RECURSION 838 #define INIT_TRACE_RECURSION 839 #endif 840 841 #ifdef CONFIG_FTRACE_SYSCALLS 842 843 unsigned long arch_syscall_addr(int nr); 844 845 #endif /* CONFIG_FTRACE_SYSCALLS */ 846 847 #endif /* _LINUX_FTRACE_H */ 848