include/linux/ftrace.h

   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/ktime.h>
  14 #include <linux/sched.h>
  15 #include <linux/types.h>
  16 #include <linux/init.h>
  17 #include <linux/fs.h>
  18
  19 #include <asm/ftrace.h>
  20
  21 struct module;
  22 struct ftrace_hash;
  23
  24 #ifdef CONFIG_FUNCTION_TRACER
  25
  26 extern int ftrace_enabled;
  27 extern int
  28 ftrace_enable_sysctl(struct ctl_table *table, int write,
  29                      void __user *buffer, size_t *lenp,
  30                      loff_t *ppos);
  31
  32 typedef void (*ftrace_func_t)(unsigned long ip, unsigned long parent_ip);
  33
  34 /*
  35  * FTRACE_OPS_FL_* bits denote the state of ftrace_ops struct and are
  36  * set in the flags member.
  37  *
  38  * ENABLED - set/unset when ftrace_ops is registered/unregistered
  39  * GLOBAL  - set manualy by ftrace_ops user to denote the ftrace_ops
  40  *           is part of the global tracers sharing the same filter
  41  *           via set_ftrace_* debugfs files.
  42  * DYNAMIC - set when ftrace_ops is registered to denote dynamically
  43  *           allocated ftrace_ops which need special care
  44  * CONTROL - set manualy by ftrace_ops user to denote the ftrace_ops
  45  *           could be controled by following calls:
  46  *             ftrace_function_local_enable
  47  *             ftrace_function_local_disable
  48  */
  49 enum {
  50         FTRACE_OPS_FL_ENABLED           = 1 << 0,
  51         FTRACE_OPS_FL_GLOBAL            = 1 << 1,
  52         FTRACE_OPS_FL_DYNAMIC           = 1 << 2,
  53         FTRACE_OPS_FL_CONTROL           = 1 << 3,
  54 };
  55
  56 struct ftrace_ops {
  57         ftrace_func_t                   func;
  58         struct ftrace_ops               *next;
  59         unsigned long                   flags;
  60         int __percpu                    *disabled;
  61 #ifdef CONFIG_DYNAMIC_FTRACE
  62         struct ftrace_hash              *notrace_hash;
  63         struct ftrace_hash              *filter_hash;
  64 #endif
  65 };
  66
  67 extern int function_trace_stop;
  68
  69 /*
  70  * Type of the current tracing.
  71  */
  72 enum ftrace_tracing_type_t {
  73         FTRACE_TYPE_ENTER = 0, /* Hook the call of the function */
  74         FTRACE_TYPE_RETURN,     /* Hook the return of the function */
  75 };
  76
  77 /* Current tracing type, default is FTRACE_TYPE_ENTER */
  78 extern enum ftrace_tracing_type_t ftrace_tracing_type;
  79
  80 /**
  81  * ftrace_stop - stop function tracer.
  82  *
  83  * A quick way to stop the function tracer. Note this an on off switch,
  84  * it is not something that is recursive like preempt_disable.
  85  * This does not disable the calling of mcount, it only stops the
  86  * calling of functions from mcount.
  87  */
  88 static inline void ftrace_stop(void)
  89 {
  90         function_trace_stop = 1;
  91 }
  92
  93 /**
  94  * ftrace_start - start the function tracer.
  95  *
  96  * This function is the inverse of ftrace_stop. This does not enable
  97  * the function tracing if the function tracer is disabled. This only
  98  * sets the function tracer flag to continue calling the functions
  99  * from mcount.
 100  */
 101 static inline void ftrace_start(void)
 102 {
 103         function_trace_stop = 0;
 104 }
 105
 106 /*
 107  * The ftrace_ops must be a static and should also
 108  * be read_mostly.  These functions do modify read_mostly variables
 109  * so use them sparely. Never free an ftrace_op or modify the
 110  * next pointer after it has been registered. Even after unregistering
 111  * it, the next pointer may still be used internally.
 112  */
 113 int register_ftrace_function(struct ftrace_ops *ops);
 114 int unregister_ftrace_function(struct ftrace_ops *ops);
 115 void clear_ftrace_function(void);
 116
 117 /**
 118  * ftrace_function_local_enable - enable controlled ftrace_ops on current cpu
 119  *
 120  * This function enables tracing on current cpu by decreasing
 121  * the per cpu control variable.
 122  * It must be called with preemption disabled and only on ftrace_ops
 123  * registered with FTRACE_OPS_FL_CONTROL. If called without preemption
 124  * disabled, this_cpu_ptr will complain when CONFIG_DEBUG_PREEMPT is enabled.
 125  */
 126 static inline void ftrace_function_local_enable(struct ftrace_ops *ops)
 127 {
 128         if (WARN_ON_ONCE(!(ops->flags & FTRACE_OPS_FL_CONTROL)))
 129                 return;
 130
 131         (*this_cpu_ptr(ops->disabled))--;
 132 }
 133
 134 /**
 135  * ftrace_function_local_disable - enable controlled ftrace_ops on current cpu
 136  *
 137  * This function enables tracing on current cpu by decreasing
 138  * the per cpu control variable.
 139  * It must be called with preemption disabled and only on ftrace_ops
 140  * registered with FTRACE_OPS_FL_CONTROL. If called without preemption
 141  * disabled, this_cpu_ptr will complain when CONFIG_DEBUG_PREEMPT is enabled.
 142  */
 143 static inline void ftrace_function_local_disable(struct ftrace_ops *ops)
 144 {
 145         if (WARN_ON_ONCE(!(ops->flags & FTRACE_OPS_FL_CONTROL)))
 146                 return;
 147
 148         (*this_cpu_ptr(ops->disabled))++;
 149 }
 150
 151 /**
 152  * ftrace_function_local_disabled - returns ftrace_ops disabled value
 153  *                                  on current cpu
 154  *
 155  * This function returns value of ftrace_ops::disabled on current cpu.
 156  * It must be called with preemption disabled and only on ftrace_ops
 157  * registered with FTRACE_OPS_FL_CONTROL. If called without preemption
 158  * disabled, this_cpu_ptr will complain when CONFIG_DEBUG_PREEMPT is enabled.
 159  */
 160 static inline int ftrace_function_local_disabled(struct ftrace_ops *ops)
 161 {
 162         WARN_ON_ONCE(!(ops->flags & FTRACE_OPS_FL_CONTROL));
 163         return *this_cpu_ptr(ops->disabled);
 164 }
 165
 166 extern void ftrace_stub(unsigned long a0, unsigned long a1);
 167
 168 #else /* !CONFIG_FUNCTION_TRACER */
 169 /*
 170  * (un)register_ftrace_function must be a macro since the ops parameter
 171  * must not be evaluated.
 172  */
 173 #define register_ftrace_function(ops) ({ 0; })
 174 #define unregister_ftrace_function(ops) ({ 0; })
 175 static inline void clear_ftrace_function(void) { }
 176 static inline void ftrace_kill(void) { }
 177 static inline void ftrace_stop(void) { }
 178 static inline void ftrace_start(void) { }
 179 #endif /* CONFIG_FUNCTION_TRACER */
 180
 181 #ifdef CONFIG_STACK_TRACER
 182 extern int stack_tracer_enabled;
 183 int
 184 stack_trace_sysctl(struct ctl_table *table, int write,
 185                    void __user *buffer, size_t *lenp,
 186                    loff_t *ppos);
 187 #endif
 188
 189 struct ftrace_func_command {
 190         struct list_head        list;
 191         char                    *name;
 192         int                     (*func)(struct ftrace_hash *hash,
 193                                         char *func, char *cmd,
 194                                         char *params, int enable);
 195 };
 196
 197 #ifdef CONFIG_DYNAMIC_FTRACE
 198
 199 int ftrace_arch_code_modify_prepare(void);
 200 int ftrace_arch_code_modify_post_process(void);
 201
 202 void ftrace_bug(int err, unsigned long ip);
 203
 204 struct seq_file;
 205
 206 struct ftrace_probe_ops {
 207         void                    (*func)(unsigned long ip,
 208                                         unsigned long parent_ip,
 209                                         void **data);
 210         int                     (*callback)(unsigned long ip, void **data);
 211         void                    (*free)(void **data);
 212         int                     (*print)(struct seq_file *m,
 213                                          unsigned long ip,
 214                                          struct ftrace_probe_ops *ops,
 215                                          void *data);
 216 };
 217
 218 extern int
 219 register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
 220                               void *data);
 221 extern void
 222 unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
 223                                 void *data);
 224 extern void
 225 unregister_ftrace_function_probe_func(char *glob, struct ftrace_probe_ops *ops);
 226 extern void unregister_ftrace_function_probe_all(char *glob);
 227
 228 extern int ftrace_text_reserved(void *start, void *end);
 229
 230 enum {
 231         FTRACE_FL_ENABLED       = (1 << 30),
 232 };
 233
 234 #define FTRACE_FL_MASK          (0x3UL << 30)
 235 #define FTRACE_REF_MAX          ((1 << 30) - 1)
 236
 237 struct dyn_ftrace {
 238         union {
 239                 unsigned long           ip; /* address of mcount call-site */
 240                 struct dyn_ftrace       *freelist;
 241         };
 242         unsigned long           flags;
 243         struct dyn_arch_ftrace          arch;
 244 };
 245
 246 int ftrace_force_update(void);
 247 int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf,
 248                        int len, int reset);
 249 int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,
 250                         int len, int reset);
 251 void ftrace_set_global_filter(unsigned char *buf, int len, int reset);
 252 void ftrace_set_global_notrace(unsigned char *buf, int len, int reset);
 253 void ftrace_free_filter(struct ftrace_ops *ops);
 254
 255 int register_ftrace_command(struct ftrace_func_command *cmd);
 256 int unregister_ftrace_command(struct ftrace_func_command *cmd);
 257
 258 enum {
 259         FTRACE_UPDATE_CALLS             = (1 << 0),
 260         FTRACE_DISABLE_CALLS            = (1 << 1),
 261         FTRACE_UPDATE_TRACE_FUNC        = (1 << 2),
 262         FTRACE_START_FUNC_RET           = (1 << 3),
 263         FTRACE_STOP_FUNC_RET            = (1 << 4),
 264 };
 265
 266 enum {
 267         FTRACE_UPDATE_IGNORE,
 268         FTRACE_UPDATE_MAKE_CALL,
 269         FTRACE_UPDATE_MAKE_NOP,
 270 };
 271
 272 enum {
 273         FTRACE_ITER_FILTER      = (1 << 0),
 274         FTRACE_ITER_NOTRACE     = (1 << 1),
 275         FTRACE_ITER_PRINTALL    = (1 << 2),
 276         FTRACE_ITER_DO_HASH     = (1 << 3),
 277         FTRACE_ITER_HASH        = (1 << 4),
 278         FTRACE_ITER_ENABLED     = (1 << 5),
 279 };
 280
 281 void arch_ftrace_update_code(int command);
 282
 283 struct ftrace_rec_iter;
 284
 285 struct ftrace_rec_iter *ftrace_rec_iter_start(void);
 286 struct ftrace_rec_iter *ftrace_rec_iter_next(struct ftrace_rec_iter *iter);
 287 struct dyn_ftrace *ftrace_rec_iter_record(struct ftrace_rec_iter *iter);
 288
 289 #define for_ftrace_rec_iter(iter)               \
 290         for (iter = ftrace_rec_iter_start();    \
 291              iter;                              \
 292              iter = ftrace_rec_iter_next(iter))
 293
 294
 295 int ftrace_update_record(struct dyn_ftrace *rec, int enable);
 296 int ftrace_test_record(struct dyn_ftrace *rec, int enable);
 297 void ftrace_run_stop_machine(int command);
 298 unsigned long ftrace_location(unsigned long ip);
 299
 300 extern ftrace_func_t ftrace_trace_function;
 301
 302 int ftrace_regex_open(struct ftrace_ops *ops, int flag,
 303                   struct inode *inode, struct file *file);
 304 ssize_t ftrace_filter_write(struct file *file, const char __user *ubuf,
 305                             size_t cnt, loff_t *ppos);
 306 ssize_t ftrace_notrace_write(struct file *file, const char __user *ubuf,
 307                              size_t cnt, loff_t *ppos);
 308 loff_t ftrace_regex_lseek(struct file *file, loff_t offset, int origin);
 309 int ftrace_regex_release(struct inode *inode, struct file *file);
 310
 311 void __init
 312 ftrace_set_early_filter(struct ftrace_ops *ops, char *buf, int enable);
 313
 314 /* defined in arch */
 315 extern int ftrace_ip_converted(unsigned long ip);
 316 extern int ftrace_dyn_arch_init(void *data);
 317 extern int ftrace_update_ftrace_func(ftrace_func_t func);
 318 extern void ftrace_caller(void);
 319 extern void ftrace_call(void);
 320 extern void mcount_call(void);
 321
 322 void ftrace_modify_all_code(int command);
 323
 324 #ifndef FTRACE_ADDR
 325 #define FTRACE_ADDR ((unsigned long)ftrace_caller)
 326 #endif
 327 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
 328 extern void ftrace_graph_caller(void);
 329 extern int ftrace_enable_ftrace_graph_caller(void);
 330 extern int ftrace_disable_ftrace_graph_caller(void);
 331 #else
 332 static inline int ftrace_enable_ftrace_graph_caller(void) { return 0; }
 333 static inline int ftrace_disable_ftrace_graph_caller(void) { return 0; }
 334 #endif
 335
 336 /**
 337  * ftrace_make_nop - convert code into nop
 338  * @mod: module structure if called by module load initialization
 339  * @rec: the mcount call site record
 340  * @addr: the address that the call site should be calling
 341  *
 342  * This is a very sensitive operation and great care needs
 343  * to be taken by the arch.  The operation should carefully
 344  * read the location, check to see if what is read is indeed
 345  * what we expect it to be, and then on success of the compare,
 346  * it should write to the location.
 347  *
 348  * The code segment at @rec->ip should be a caller to @addr
 349  *
 350  * Return must be:
 351  *  0 on success
 352  *  -EFAULT on error reading the location
 353  *  -EINVAL on a failed compare of the contents
 354  *  -EPERM  on error writing to the location
 355  * Any other value will be considered a failure.
 356  */
 357 extern int ftrace_make_nop(struct module *mod,
 358                            struct dyn_ftrace *rec, unsigned long addr);
 359
 360 /**
 361  * ftrace_make_call - convert a nop call site into a call to addr
 362  * @rec: the mcount call site record
 363  * @addr: the address that the call site should call
 364  *
 365  * This is a very sensitive operation and great care needs
 366  * to be taken by the arch.  The operation should carefully
 367  * read the location, check to see if what is read is indeed
 368  * what we expect it to be, and then on success of the compare,
 369  * it should write to the location.
 370  *
 371  * The code segment at @rec->ip should be a nop
 372  *
 373  * Return must be:
 374  *  0 on success
 375  *  -EFAULT on error reading the location
 376  *  -EINVAL on a failed compare of the contents
 377  *  -EPERM  on error writing to the location
 378  * Any other value will be considered a failure.
 379  */
 380 extern int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr);
 381
 382 /* May be defined in arch */
 383 extern int ftrace_arch_read_dyn_info(char *buf, int size);
 384
 385 extern int skip_trace(unsigned long ip);
 386
 387 extern void ftrace_disable_daemon(void);
 388 extern void ftrace_enable_daemon(void);
 389 #else
 390 static inline int skip_trace(unsigned long ip) { return 0; }
 391 static inline int ftrace_force_update(void) { return 0; }
 392 static inline void ftrace_disable_daemon(void) { }
 393 static inline void ftrace_enable_daemon(void) { }
 394 static inline void ftrace_release_mod(struct module *mod) {}
 395 static inline int register_ftrace_command(struct ftrace_func_command *cmd)
 396 {
 397         return -EINVAL;
 398 }
 399 static inline int unregister_ftrace_command(char *cmd_name)
 400 {
 401         return -EINVAL;
 402 }
 403 static inline int ftrace_text_reserved(void *start, void *end)
 404 {
 405         return 0;
 406 }
 407
 408 /*
 409  * Again users of functions that have ftrace_ops may not
 410  * have them defined when ftrace is not enabled, but these
 411  * functions may still be called. Use a macro instead of inline.
 412  */
 413 #define ftrace_regex_open(ops, flag, inod, file) ({ -ENODEV; })
 414 #define ftrace_set_early_filter(ops, buf, enable) do { } while (0)
 415 #define ftrace_set_filter(ops, buf, len, reset) ({ -ENODEV; })
 416 #define ftrace_set_notrace(ops, buf, len, reset) ({ -ENODEV; })
 417 #define ftrace_free_filter(ops) do { } while (0)
 418
 419 static inline ssize_t ftrace_filter_write(struct file *file, const char __user *ubuf,
 420                             size_t cnt, loff_t *ppos) { return -ENODEV; }
 421 static inline ssize_t ftrace_notrace_write(struct file *file, const char __user *ubuf,
 422                              size_t cnt, loff_t *ppos) { return -ENODEV; }
 423 static inline loff_t ftrace_regex_lseek(struct file *file, loff_t offset, int origin)
 424 {
 425         return -ENODEV;
 426 }
 427 static inline int
 428 ftrace_regex_release(struct inode *inode, struct file *file) { return -ENODEV; }
 429 #endif /* CONFIG_DYNAMIC_FTRACE */
 430
 431 /* totally disable ftrace - can not re-enable after this */
 432 void ftrace_kill(void);
 433
 434 static inline void tracer_disable(void)
 435 {
 436 #ifdef CONFIG_FUNCTION_TRACER
 437         ftrace_enabled = 0;
 438 #endif
 439 }
 440
 441 /*
 442  * Ftrace disable/restore without lock. Some synchronization mechanism
 443  * must be used to prevent ftrace_enabled to be changed between
 444  * disable/restore.
 445  */
 446 static inline int __ftrace_enabled_save(void)
 447 {
 448 #ifdef CONFIG_FUNCTION_TRACER
 449         int saved_ftrace_enabled = ftrace_enabled;
 450         ftrace_enabled = 0;
 451         return saved_ftrace_enabled;
 452 #else
 453         return 0;
 454 #endif
 455 }
 456
 457 static inline void __ftrace_enabled_restore(int enabled)
 458 {
 459 #ifdef CONFIG_FUNCTION_TRACER
 460         ftrace_enabled = enabled;
 461 #endif
 462 }
 463
 464 #ifndef HAVE_ARCH_CALLER_ADDR
 465 # ifdef CONFIG_FRAME_POINTER
 466 #  define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0))
 467 #  define CALLER_ADDR1 ((unsigned long)__builtin_return_address(1))
 468 #  define CALLER_ADDR2 ((unsigned long)__builtin_return_address(2))
 469 #  define CALLER_ADDR3 ((unsigned long)__builtin_return_address(3))
 470 #  define CALLER_ADDR4 ((unsigned long)__builtin_return_address(4))
 471 #  define CALLER_ADDR5 ((unsigned long)__builtin_return_address(5))
 472 #  define CALLER_ADDR6 ((unsigned long)__builtin_return_address(6))
 473 # else
 474 #  define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0))
 475 #  define CALLER_ADDR1 0UL
 476 #  define CALLER_ADDR2 0UL
 477 #  define CALLER_ADDR3 0UL
 478 #  define CALLER_ADDR4 0UL
 479 #  define CALLER_ADDR5 0UL
 480 #  define CALLER_ADDR6 0UL
 481 # endif
 482 #endif /* ifndef HAVE_ARCH_CALLER_ADDR */
 483
 484 #ifdef CONFIG_IRQSOFF_TRACER
 485   extern void time_hardirqs_on(unsigned long a0, unsigned long a1);
 486   extern void time_hardirqs_off(unsigned long a0, unsigned long a1);
 487 #else
 488   static inline void time_hardirqs_on(unsigned long a0, unsigned long a1) { }
 489   static inline void time_hardirqs_off(unsigned long a0, unsigned long a1) { }
 490 #endif
 491
 492 #ifdef CONFIG_PREEMPT_TRACER
 493   extern void trace_preempt_on(unsigned long a0, unsigned long a1);
 494   extern void trace_preempt_off(unsigned long a0, unsigned long a1);
 495 #else
 496 /*
 497  * Use defines instead of static inlines because some arches will make code out
 498  * of the CALLER_ADDR, when we really want these to be a real nop.
 499  */
 500 # define trace_preempt_on(a0, a1) do { } while (0)
 501 # define trace_preempt_off(a0, a1) do { } while (0)
 502 #endif
 503
 504 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
 505 extern void ftrace_init(void);
 506 #else
 507 static inline void ftrace_init(void) { }
 508 #endif
 509
 510 /*
 511  * Structure that defines an entry function trace.
 512  */
 513 struct ftrace_graph_ent {
 514         unsigned long func; /* Current function */
 515         int depth;
 516 };
 517
 518 /*
 519  * Structure that defines a return function trace.
 520  */
 521 struct ftrace_graph_ret {
 522         unsigned long func; /* Current function */
 523         unsigned long long calltime;
 524         unsigned long long rettime;
 525         /* Number of functions that overran the depth limit for current task */
 526         unsigned long overrun;
 527         int depth;
 528 };
 529
 530 /* Type of the callback handlers for tracing function graph*/
 531 typedef void (*trace_func_graph_ret_t)(struct ftrace_graph_ret *); /* return */
 532 typedef int (*trace_func_graph_ent_t)(struct ftrace_graph_ent *); /* entry */
 533
 534 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
 535
 536 /* for init task */
 537 #define INIT_FTRACE_GRAPH               .ret_stack = NULL,
 538
 539 /*
 540  * Stack of return addresses for functions
 541  * of a thread.
 542  * Used in struct thread_info
 543  */
 544 struct ftrace_ret_stack {
 545         unsigned long ret;
 546         unsigned long func;
 547         unsigned long long calltime;
 548         unsigned long long subtime;
 549         unsigned long fp;
 550 };
 551
 552 /*
 553  * Primary handler of a function return.
 554  * It relays on ftrace_return_to_handler.
 555  * Defined in entry_32/64.S
 556  */
 557 extern void return_to_handler(void);
 558
 559 extern int
 560 ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth,
 561                          unsigned long frame_pointer);
 562
 563 /*
 564  * Sometimes we don't want to trace a function with the function
 565  * graph tracer but we want them to keep traced by the usual function
 566  * tracer if the function graph tracer is not configured.
 567  */
 568 #define __notrace_funcgraph             notrace
 569
 570 /*
 571  * We want to which function is an entrypoint of a hardirq.
 572  * That will help us to put a signal on output.
 573  */
 574 #define __irq_entry              __attribute__((__section__(".irqentry.text")))
 575
 576 /* Limits of hardirq entrypoints */
 577 extern char __irqentry_text_start[];
 578 extern char __irqentry_text_end[];
 579
 580 #define FTRACE_RETFUNC_DEPTH 50
 581 #define FTRACE_RETSTACK_ALLOC_SIZE 32
 582 extern int register_ftrace_graph(trace_func_graph_ret_t retfunc,
 583                                 trace_func_graph_ent_t entryfunc);
 584
 585 extern void ftrace_graph_stop(void);
 586
 587 /* The current handlers in use */
 588 extern trace_func_graph_ret_t ftrace_graph_return;
 589 extern trace_func_graph_ent_t ftrace_graph_entry;
 590
 591 extern void unregister_ftrace_graph(void);
 592
 593 extern void ftrace_graph_init_task(struct task_struct *t);
 594 extern void ftrace_graph_exit_task(struct task_struct *t);
 595 extern void ftrace_graph_init_idle_task(struct task_struct *t, int cpu);
 596
 597 static inline int task_curr_ret_stack(struct task_struct *t)
 598 {
 599         return t->curr_ret_stack;
 600 }
 601
 602 static inline void pause_graph_tracing(void)
 603 {
 604         atomic_inc(&current->tracing_graph_pause);
 605 }
 606
 607 static inline void unpause_graph_tracing(void)
 608 {
 609         atomic_dec(&current->tracing_graph_pause);
 610 }
 611 #else /* !CONFIG_FUNCTION_GRAPH_TRACER */
 612
 613 #define __notrace_funcgraph
 614 #define __irq_entry
 615 #define INIT_FTRACE_GRAPH
 616
 617 static inline void ftrace_graph_init_task(struct task_struct *t) { }
 618 static inline void ftrace_graph_exit_task(struct task_struct *t) { }
 619 static inline void ftrace_graph_init_idle_task(struct task_struct *t, int cpu) { }
 620
 621 static inline int register_ftrace_graph(trace_func_graph_ret_t retfunc,
 622                           trace_func_graph_ent_t entryfunc)
 623 {
 624         return -1;
 625 }
 626 static inline void unregister_ftrace_graph(void) { }
 627
 628 static inline int task_curr_ret_stack(struct task_struct *tsk)
 629 {
 630         return -1;
 631 }
 632
 633 static inline void pause_graph_tracing(void) { }
 634 static inline void unpause_graph_tracing(void) { }
 635 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
 636
 637 #ifdef CONFIG_TRACING
 638
 639 /* flags for current->trace */
 640 enum {
 641         TSK_TRACE_FL_TRACE_BIT  = 0,
 642         TSK_TRACE_FL_GRAPH_BIT  = 1,
 643 };
 644 enum {
 645         TSK_TRACE_FL_TRACE      = 1 << TSK_TRACE_FL_TRACE_BIT,
 646         TSK_TRACE_FL_GRAPH      = 1 << TSK_TRACE_FL_GRAPH_BIT,
 647 };
 648
 649 static inline void set_tsk_trace_trace(struct task_struct *tsk)
 650 {
 651         set_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace);
 652 }
 653
 654 static inline void clear_tsk_trace_trace(struct task_struct *tsk)
 655 {
 656         clear_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace);
 657 }
 658
 659 static inline int test_tsk_trace_trace(struct task_struct *tsk)
 660 {
 661         return tsk->trace & TSK_TRACE_FL_TRACE;
 662 }
 663
 664 static inline void set_tsk_trace_graph(struct task_struct *tsk)
 665 {
 666         set_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace);
 667 }
 668
 669 static inline void clear_tsk_trace_graph(struct task_struct *tsk)
 670 {
 671         clear_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace);
 672 }
 673
 674 static inline int test_tsk_trace_graph(struct task_struct *tsk)
 675 {
 676         return tsk->trace & TSK_TRACE_FL_GRAPH;
 677 }
 678
 679 enum ftrace_dump_mode;
 680
 681 extern enum ftrace_dump_mode ftrace_dump_on_oops;
 682
 683 #ifdef CONFIG_PREEMPT
 684 #define INIT_TRACE_RECURSION            .trace_recursion = 0,
 685 #endif
 686
 687 #endif /* CONFIG_TRACING */
 688
 689 #ifndef INIT_TRACE_RECURSION
 690 #define INIT_TRACE_RECURSION
 691 #endif
 692
 693 #ifdef CONFIG_FTRACE_SYSCALLS
 694
 695 unsigned long arch_syscall_addr(int nr);
 696
 697 #endif /* CONFIG_FTRACE_SYSCALLS */
 698
 699 #endif /* _LINUX_FTRACE_H */