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   1 #ifndef _LINUX_KERNEL_TRACE_H
   2 #define _LINUX_KERNEL_TRACE_H
   3
   4 #include <linux/fs.h>
   5 #include <asm/atomic.h>
   6 #include <linux/sched.h>
   7 #include <linux/clocksource.h>
   8 #include <linux/ring_buffer.h>
   9 #include <linux/mmiotrace.h>
  10 #include <linux/ftrace.h>
  11 #include <trace/boot.h>
  12 #include <linux/kmemtrace.h>
  13 #include <trace/power.h>
  14
  15 #include <linux/trace_seq.h>
  16 #include <linux/ftrace_event.h>
  17
  18 enum trace_type {
  19         __TRACE_FIRST_TYPE = 0,
  20
  21         TRACE_FN,
  22         TRACE_CTX,
  23         TRACE_WAKE,
  24         TRACE_STACK,
  25         TRACE_PRINT,
  26         TRACE_BPRINT,
  27         TRACE_SPECIAL,
  28         TRACE_MMIO_RW,
  29         TRACE_MMIO_MAP,
  30         TRACE_BRANCH,
  31         TRACE_BOOT_CALL,
  32         TRACE_BOOT_RET,
  33         TRACE_GRAPH_RET,
  34         TRACE_GRAPH_ENT,
  35         TRACE_USER_STACK,
  36         TRACE_HW_BRANCHES,
  37         TRACE_KMEM_ALLOC,
  38         TRACE_KMEM_FREE,
  39         TRACE_POWER,
  40         TRACE_BLK,
  41
  42         __TRACE_LAST_TYPE,
  43 };
  44
  45 /*
  46  * Function trace entry - function address and parent function addres:
  47  */
  48 struct ftrace_entry {
  49         struct trace_entry      ent;
  50         unsigned long           ip;
  51         unsigned long           parent_ip;
  52 };
  53
  54 /* Function call entry */
  55 struct ftrace_graph_ent_entry {
  56         struct trace_entry              ent;
  57         struct ftrace_graph_ent         graph_ent;
  58 };
  59
  60 /* Function return entry */
  61 struct ftrace_graph_ret_entry {
  62         struct trace_entry              ent;
  63         struct ftrace_graph_ret         ret;
  64 };
  65 extern struct tracer boot_tracer;
  66
  67 /*
  68  * Context switch trace entry - which task (and prio) we switched from/to:
  69  */
  70 struct ctx_switch_entry {
  71         struct trace_entry      ent;
  72         unsigned int            prev_pid;
  73         unsigned char           prev_prio;
  74         unsigned char           prev_state;
  75         unsigned int            next_pid;
  76         unsigned char           next_prio;
  77         unsigned char           next_state;
  78         unsigned int            next_cpu;
  79 };
  80
  81 /*
  82  * Special (free-form) trace entry:
  83  */
  84 struct special_entry {
  85         struct trace_entry      ent;
  86         unsigned long           arg1;
  87         unsigned long           arg2;
  88         unsigned long           arg3;
  89 };
  90
  91 /*
  92  * Stack-trace entry:
  93  */
  94
  95 #define FTRACE_STACK_ENTRIES    8
  96
  97 struct stack_entry {
  98         struct trace_entry      ent;
  99         unsigned long           caller[FTRACE_STACK_ENTRIES];
 100 };
 101
 102 struct userstack_entry {
 103         struct trace_entry      ent;
 104         unsigned long           caller[FTRACE_STACK_ENTRIES];
 105 };
 106
 107 /*
 108  * trace_printk entry:
 109  */
 110 struct bprint_entry {
 111         struct trace_entry      ent;
 112         unsigned long           ip;
 113         const char              *fmt;
 114         u32                     buf[];
 115 };
 116
 117 struct print_entry {
 118         struct trace_entry      ent;
 119         unsigned long           ip;
 120         char                    buf[];
 121 };
 122
 123 struct trace_mmiotrace_rw {
 124         struct trace_entry      ent;
 125         struct mmiotrace_rw     rw;
 126 };
 127
 128 struct trace_mmiotrace_map {
 129         struct trace_entry      ent;
 130         struct mmiotrace_map    map;
 131 };
 132
 133 struct trace_boot_call {
 134         struct trace_entry      ent;
 135         struct boot_trace_call boot_call;
 136 };
 137
 138 struct trace_boot_ret {
 139         struct trace_entry      ent;
 140         struct boot_trace_ret boot_ret;
 141 };
 142
 143 #define TRACE_FUNC_SIZE 30
 144 #define TRACE_FILE_SIZE 20
 145 struct trace_branch {
 146         struct trace_entry      ent;
 147         unsigned                line;
 148         char                    func[TRACE_FUNC_SIZE+1];
 149         char                    file[TRACE_FILE_SIZE+1];
 150         char                    correct;
 151 };
 152
 153 struct hw_branch_entry {
 154         struct trace_entry      ent;
 155         u64                     from;
 156         u64                     to;
 157 };
 158
 159 struct trace_power {
 160         struct trace_entry      ent;
 161         struct power_trace      state_data;
 162 };
 163
 164 enum kmemtrace_type_id {
 165         KMEMTRACE_TYPE_KMALLOC = 0,     /* kmalloc() or kfree(). */
 166         KMEMTRACE_TYPE_CACHE,           /* kmem_cache_*(). */
 167         KMEMTRACE_TYPE_PAGES,           /* __get_free_pages() and friends. */
 168 };
 169
 170 struct kmemtrace_alloc_entry {
 171         struct trace_entry      ent;
 172         enum kmemtrace_type_id  type_id;
 173         unsigned long           call_site;
 174         const void              *ptr;
 175         size_t                  bytes_req;
 176         size_t                  bytes_alloc;
 177         gfp_t                   gfp_flags;
 178         int                     node;
 179 };
 180
 181 struct kmemtrace_free_entry {
 182         struct trace_entry      ent;
 183         enum kmemtrace_type_id  type_id;
 184         unsigned long           call_site;
 185         const void              *ptr;
 186 };
 187
 188 struct syscall_trace_enter {
 189         struct trace_entry      ent;
 190         int                     nr;
 191         unsigned long           args[];
 192 };
 193
 194 struct syscall_trace_exit {
 195         struct trace_entry      ent;
 196         int                     nr;
 197         unsigned long           ret;
 198 };
 199
 200
 201 /*
 202  * trace_flag_type is an enumeration that holds different
 203  * states when a trace occurs. These are:
 204  *  IRQS_OFF            - interrupts were disabled
 205  *  IRQS_NOSUPPORT      - arch does not support irqs_disabled_flags
 206  *  NEED_RESCHED        - reschedule is requested
 207  *  HARDIRQ             - inside an interrupt handler
 208  *  SOFTIRQ             - inside a softirq handler
 209  */
 210 enum trace_flag_type {
 211         TRACE_FLAG_IRQS_OFF             = 0x01,
 212         TRACE_FLAG_IRQS_NOSUPPORT       = 0x02,
 213         TRACE_FLAG_NEED_RESCHED         = 0x04,
 214         TRACE_FLAG_HARDIRQ              = 0x08,
 215         TRACE_FLAG_SOFTIRQ              = 0x10,
 216 };
 217
 218 #define TRACE_BUF_SIZE          1024
 219
 220 /*
 221  * The CPU trace array - it consists of thousands of trace entries
 222  * plus some other descriptor data: (for example which task started
 223  * the trace, etc.)
 224  */
 225 struct trace_array_cpu {
 226         atomic_t                disabled;
 227         void                    *buffer_page;   /* ring buffer spare */
 228
 229         unsigned long           saved_latency;
 230         unsigned long           critical_start;
 231         unsigned long           critical_end;
 232         unsigned long           critical_sequence;
 233         unsigned long           nice;
 234         unsigned long           policy;
 235         unsigned long           rt_priority;
 236         unsigned long           skipped_entries;
 237         cycle_t                 preempt_timestamp;
 238         pid_t                   pid;
 239         uid_t                   uid;
 240         char                    comm[TASK_COMM_LEN];
 241 };
 242
 243 /*
 244  * The trace array - an array of per-CPU trace arrays. This is the
 245  * highest level data structure that individual tracers deal with.
 246  * They have on/off state as well:
 247  */
 248 struct trace_array {
 249         struct ring_buffer      *buffer;
 250         unsigned long           entries;
 251         int                     cpu;
 252         cycle_t                 time_start;
 253         struct task_struct      *waiter;
 254         struct trace_array_cpu  *data[NR_CPUS];
 255 };
 256
 257 #define FTRACE_CMP_TYPE(var, type) \
 258         __builtin_types_compatible_p(typeof(var), type *)
 259
 260 #undef IF_ASSIGN
 261 #define IF_ASSIGN(var, entry, etype, id)                \
 262         if (FTRACE_CMP_TYPE(var, etype)) {              \
 263                 var = (typeof(var))(entry);             \
 264                 WARN_ON(id && (entry)->type != id);     \
 265                 break;                                  \
 266         }
 267
 268 /* Will cause compile errors if type is not found. */
 269 extern void __ftrace_bad_type(void);
 270
 271 /*
 272  * The trace_assign_type is a verifier that the entry type is
 273  * the same as the type being assigned. To add new types simply
 274  * add a line with the following format:
 275  *
 276  * IF_ASSIGN(var, ent, type, id);
 277  *
 278  *  Where "type" is the trace type that includes the trace_entry
 279  *  as the "ent" item. And "id" is the trace identifier that is
 280  *  used in the trace_type enum.
 281  *
 282  *  If the type can have more than one id, then use zero.
 283  */
 284 #define trace_assign_type(var, ent)                                     \
 285         do {                                                            \
 286                 IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN);     \
 287                 IF_ASSIGN(var, ent, struct ctx_switch_entry, 0);        \
 288                 IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK);   \
 289                 IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
 290                 IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT);   \
 291                 IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT); \
 292                 IF_ASSIGN(var, ent, struct special_entry, 0);           \
 293                 IF_ASSIGN(var, ent, struct trace_mmiotrace_rw,          \
 294                           TRACE_MMIO_RW);                               \
 295                 IF_ASSIGN(var, ent, struct trace_mmiotrace_map,         \
 296                           TRACE_MMIO_MAP);                              \
 297                 IF_ASSIGN(var, ent, struct trace_boot_call, TRACE_BOOT_CALL);\
 298                 IF_ASSIGN(var, ent, struct trace_boot_ret, TRACE_BOOT_RET);\
 299                 IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
 300                 IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry,      \
 301                           TRACE_GRAPH_ENT);             \
 302                 IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry,      \
 303                           TRACE_GRAPH_RET);             \
 304                 IF_ASSIGN(var, ent, struct hw_branch_entry, TRACE_HW_BRANCHES);\
 305                 IF_ASSIGN(var, ent, struct trace_power, TRACE_POWER); \
 306                 IF_ASSIGN(var, ent, struct kmemtrace_alloc_entry,       \
 307                           TRACE_KMEM_ALLOC);    \
 308                 IF_ASSIGN(var, ent, struct kmemtrace_free_entry,        \
 309                           TRACE_KMEM_FREE);     \
 310                 __ftrace_bad_type();                                    \
 311         } while (0)
 312
 313 /*
 314  * An option specific to a tracer. This is a boolean value.
 315  * The bit is the bit index that sets its value on the
 316  * flags value in struct tracer_flags.
 317  */
 318 struct tracer_opt {
 319         const char      *name; /* Will appear on the trace_options file */
 320         u32             bit; /* Mask assigned in val field in tracer_flags */
 321 };
 322
 323 /*
 324  * The set of specific options for a tracer. Your tracer
 325  * have to set the initial value of the flags val.
 326  */
 327 struct tracer_flags {
 328         u32                     val;
 329         struct tracer_opt       *opts;
 330 };
 331
 332 /* Makes more easy to define a tracer opt */
 333 #define TRACER_OPT(s, b)        .name = #s, .bit = b
 334
 335
 336 /**
 337  * struct tracer - a specific tracer and its callbacks to interact with debugfs
 338  * @name: the name chosen to select it on the available_tracers file
 339  * @init: called when one switches to this tracer (echo name > current_tracer)
 340  * @reset: called when one switches to another tracer
 341  * @start: called when tracing is unpaused (echo 1 > tracing_enabled)
 342  * @stop: called when tracing is paused (echo 0 > tracing_enabled)
 343  * @open: called when the trace file is opened
 344  * @pipe_open: called when the trace_pipe file is opened
 345  * @wait_pipe: override how the user waits for traces on trace_pipe
 346  * @close: called when the trace file is released
 347  * @read: override the default read callback on trace_pipe
 348  * @splice_read: override the default splice_read callback on trace_pipe
 349  * @selftest: selftest to run on boot (see trace_selftest.c)
 350  * @print_headers: override the first lines that describe your columns
 351  * @print_line: callback that prints a trace
 352  * @set_flag: signals one of your private flags changed (trace_options file)
 353  * @flags: your private flags
 354  */
 355 struct tracer {
 356         const char              *name;
 357         int                     (*init)(struct trace_array *tr);
 358         void                    (*reset)(struct trace_array *tr);
 359         void                    (*start)(struct trace_array *tr);
 360         void                    (*stop)(struct trace_array *tr);
 361         void                    (*open)(struct trace_iterator *iter);
 362         void                    (*pipe_open)(struct trace_iterator *iter);
 363         void                    (*wait_pipe)(struct trace_iterator *iter);
 364         void                    (*close)(struct trace_iterator *iter);
 365         ssize_t                 (*read)(struct trace_iterator *iter,
 366                                         struct file *filp, char __user *ubuf,
 367                                         size_t cnt, loff_t *ppos);
 368         ssize_t                 (*splice_read)(struct trace_iterator *iter,
 369                                                struct file *filp,
 370                                                loff_t *ppos,
 371                                                struct pipe_inode_info *pipe,
 372                                                size_t len,
 373                                                unsigned int flags);
 374 #ifdef CONFIG_FTRACE_STARTUP_TEST
 375         int                     (*selftest)(struct tracer *trace,
 376                                             struct trace_array *tr);
 377 #endif
 378         void                    (*print_header)(struct seq_file *m);
 379         enum print_line_t       (*print_line)(struct trace_iterator *iter);
 380         /* If you handled the flag setting, return 0 */
 381         int                     (*set_flag)(u32 old_flags, u32 bit, int set);
 382         struct tracer           *next;
 383         int                     print_max;
 384         struct tracer_flags     *flags;
 385 };
 386
 387
 388 #define TRACE_PIPE_ALL_CPU      -1
 389
 390 int tracer_init(struct tracer *t, struct trace_array *tr);
 391 int tracing_is_enabled(void);
 392 void trace_wake_up(void);
 393 void tracing_reset(struct trace_array *tr, int cpu);
 394 void tracing_reset_online_cpus(struct trace_array *tr);
 395 void tracing_reset_current(int cpu);
 396 void tracing_reset_current_online_cpus(void);
 397 int tracing_open_generic(struct inode *inode, struct file *filp);
 398 struct dentry *trace_create_file(const char *name,
 399                                  mode_t mode,
 400                                  struct dentry *parent,
 401                                  void *data,
 402                                  const struct file_operations *fops);
 403
 404 struct dentry *tracing_init_dentry(void);
 405 void init_tracer_sysprof_debugfs(struct dentry *d_tracer);
 406
 407 struct ring_buffer_event;
 408
 409 struct ring_buffer_event *
 410 trace_buffer_lock_reserve(struct ring_buffer *buffer,
 411                           int type,
 412                           unsigned long len,
 413                           unsigned long flags,
 414                           int pc);
 415 void trace_buffer_unlock_commit(struct ring_buffer *buffer,
 416                                 struct ring_buffer_event *event,
 417                                 unsigned long flags, int pc);
 418
 419 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
 420                                                 struct trace_array_cpu *data);
 421
 422 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
 423                                           int *ent_cpu, u64 *ent_ts);
 424
 425 void default_wait_pipe(struct trace_iterator *iter);
 426 void poll_wait_pipe(struct trace_iterator *iter);
 427
 428 void ftrace(struct trace_array *tr,
 429                             struct trace_array_cpu *data,
 430                             unsigned long ip,
 431                             unsigned long parent_ip,
 432                             unsigned long flags, int pc);
 433 void tracing_sched_switch_trace(struct trace_array *tr,
 434                                 struct task_struct *prev,
 435                                 struct task_struct *next,
 436                                 unsigned long flags, int pc);
 437
 438 void tracing_sched_wakeup_trace(struct trace_array *tr,
 439                                 struct task_struct *wakee,
 440                                 struct task_struct *cur,
 441                                 unsigned long flags, int pc);
 442 void trace_special(struct trace_array *tr,
 443                    struct trace_array_cpu *data,
 444                    unsigned long arg1,
 445                    unsigned long arg2,
 446                    unsigned long arg3, int pc);
 447 void trace_function(struct trace_array *tr,
 448                     unsigned long ip,
 449                     unsigned long parent_ip,
 450                     unsigned long flags, int pc);
 451
 452 void trace_graph_return(struct ftrace_graph_ret *trace);
 453 int trace_graph_entry(struct ftrace_graph_ent *trace);
 454 void set_graph_array(struct trace_array *tr);
 455
 456 void tracing_start_cmdline_record(void);
 457 void tracing_stop_cmdline_record(void);
 458 void tracing_sched_switch_assign_trace(struct trace_array *tr);
 459 void tracing_stop_sched_switch_record(void);
 460 void tracing_start_sched_switch_record(void);
 461 int register_tracer(struct tracer *type);
 462 void unregister_tracer(struct tracer *type);
 463
 464 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
 465
 466 #ifdef CONFIG_TRACER_MAX_TRACE
 467 extern unsigned long tracing_max_latency;
 468 extern unsigned long tracing_thresh;
 469
 470 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu);
 471 void update_max_tr_single(struct trace_array *tr,
 472                           struct task_struct *tsk, int cpu);
 473 #endif /* CONFIG_TRACER_MAX_TRACE */
 474
 475 #ifdef CONFIG_STACKTRACE
 476 void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags,
 477                         int skip, int pc);
 478
 479 void ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags,
 480                             int pc);
 481
 482 void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
 483                    int pc);
 484 #else
 485 static inline void ftrace_trace_stack(struct trace_array *tr,
 486                                       unsigned long flags, int skip, int pc)
 487 {
 488 }
 489
 490 static inline void ftrace_trace_userstack(struct trace_array *tr,
 491                                           unsigned long flags, int pc)
 492 {
 493 }
 494
 495 static inline void __trace_stack(struct trace_array *tr, unsigned long flags,
 496                                  int skip, int pc)
 497 {
 498 }
 499 #endif /* CONFIG_STACKTRACE */
 500
 501 extern cycle_t ftrace_now(int cpu);
 502
 503 extern void trace_find_cmdline(int pid, char comm[]);
 504
 505 #ifdef CONFIG_DYNAMIC_FTRACE
 506 extern unsigned long ftrace_update_tot_cnt;
 507 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
 508 extern int DYN_FTRACE_TEST_NAME(void);
 509 #endif
 510
 511 extern int ring_buffer_expanded;
 512 extern bool tracing_selftest_disabled;
 513 DECLARE_PER_CPU(local_t, ftrace_cpu_disabled);
 514
 515 #ifdef CONFIG_FTRACE_STARTUP_TEST
 516 extern int trace_selftest_startup_function(struct tracer *trace,
 517                                            struct trace_array *tr);
 518 extern int trace_selftest_startup_function_graph(struct tracer *trace,
 519                                                  struct trace_array *tr);
 520 extern int trace_selftest_startup_irqsoff(struct tracer *trace,
 521                                           struct trace_array *tr);
 522 extern int trace_selftest_startup_preemptoff(struct tracer *trace,
 523                                              struct trace_array *tr);
 524 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
 525                                                  struct trace_array *tr);
 526 extern int trace_selftest_startup_wakeup(struct tracer *trace,
 527                                          struct trace_array *tr);
 528 extern int trace_selftest_startup_nop(struct tracer *trace,
 529                                          struct trace_array *tr);
 530 extern int trace_selftest_startup_sched_switch(struct tracer *trace,
 531                                                struct trace_array *tr);
 532 extern int trace_selftest_startup_sysprof(struct tracer *trace,
 533                                                struct trace_array *tr);
 534 extern int trace_selftest_startup_branch(struct tracer *trace,
 535                                          struct trace_array *tr);
 536 extern int trace_selftest_startup_hw_branches(struct tracer *trace,
 537                                               struct trace_array *tr);
 538 #endif /* CONFIG_FTRACE_STARTUP_TEST */
 539
 540 extern void *head_page(struct trace_array_cpu *data);
 541 extern unsigned long long ns2usecs(cycle_t nsec);
 542 extern int
 543 trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
 544 extern int
 545 trace_vprintk(unsigned long ip, const char *fmt, va_list args);
 546 extern int
 547 trace_array_vprintk(struct trace_array *tr,
 548                     unsigned long ip, const char *fmt, va_list args);
 549 int trace_array_printk(struct trace_array *tr,
 550                        unsigned long ip, const char *fmt, ...);
 551
 552 extern unsigned long trace_flags;
 553
 554 extern int trace_clock_id;
 555
 556 /* Standard output formatting function used for function return traces */
 557 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
 558 extern enum print_line_t print_graph_function(struct trace_iterator *iter);
 559 extern enum print_line_t
 560 trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
 561
 562 #ifdef CONFIG_DYNAMIC_FTRACE
 563 /* TODO: make this variable */
 564 #define FTRACE_GRAPH_MAX_FUNCS          32
 565 extern int ftrace_graph_count;
 566 extern unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS];
 567
 568 static inline int ftrace_graph_addr(unsigned long addr)
 569 {
 570         int i;
 571
 572         if (!ftrace_graph_count || test_tsk_trace_graph(current))
 573                 return 1;
 574
 575         for (i = 0; i < ftrace_graph_count; i++) {
 576                 if (addr == ftrace_graph_funcs[i])
 577                         return 1;
 578         }
 579
 580         return 0;
 581 }
 582 #else
 583 static inline int ftrace_trace_addr(unsigned long addr)
 584 {
 585         return 1;
 586 }
 587 static inline int ftrace_graph_addr(unsigned long addr)
 588 {
 589         return 1;
 590 }
 591 #endif /* CONFIG_DYNAMIC_FTRACE */
 592 #else /* CONFIG_FUNCTION_GRAPH_TRACER */
 593 static inline enum print_line_t
 594 print_graph_function(struct trace_iterator *iter)
 595 {
 596         return TRACE_TYPE_UNHANDLED;
 597 }
 598 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
 599
 600 extern struct pid *ftrace_pid_trace;
 601
 602 #ifdef CONFIG_FUNCTION_TRACER
 603 static inline int ftrace_trace_task(struct task_struct *task)
 604 {
 605         if (!ftrace_pid_trace)
 606                 return 1;
 607
 608         return test_tsk_trace_trace(task);
 609 }
 610 #else
 611 static inline int ftrace_trace_task(struct task_struct *task)
 612 {
 613         return 1;
 614 }
 615 #endif
 616
 617 /*
 618  * trace_iterator_flags is an enumeration that defines bit
 619  * positions into trace_flags that controls the output.
 620  *
 621  * NOTE: These bits must match the trace_options array in
 622  *       trace.c.
 623  */
 624 enum trace_iterator_flags {
 625         TRACE_ITER_PRINT_PARENT         = 0x01,
 626         TRACE_ITER_SYM_OFFSET           = 0x02,
 627         TRACE_ITER_SYM_ADDR             = 0x04,
 628         TRACE_ITER_VERBOSE              = 0x08,
 629         TRACE_ITER_RAW                  = 0x10,
 630         TRACE_ITER_HEX                  = 0x20,
 631         TRACE_ITER_BIN                  = 0x40,
 632         TRACE_ITER_BLOCK                = 0x80,
 633         TRACE_ITER_STACKTRACE           = 0x100,
 634         TRACE_ITER_SCHED_TREE           = 0x200,
 635         TRACE_ITER_PRINTK               = 0x400,
 636         TRACE_ITER_PREEMPTONLY          = 0x800,
 637         TRACE_ITER_BRANCH               = 0x1000,
 638         TRACE_ITER_ANNOTATE             = 0x2000,
 639         TRACE_ITER_USERSTACKTRACE       = 0x4000,
 640         TRACE_ITER_SYM_USEROBJ          = 0x8000,
 641         TRACE_ITER_PRINTK_MSGONLY       = 0x10000,
 642         TRACE_ITER_CONTEXT_INFO         = 0x20000, /* Print pid/cpu/time */
 643         TRACE_ITER_LATENCY_FMT          = 0x40000,
 644         TRACE_ITER_SLEEP_TIME           = 0x80000,
 645         TRACE_ITER_GRAPH_TIME           = 0x100000,
 646 };
 647
 648 /*
 649  * TRACE_ITER_SYM_MASK masks the options in trace_flags that
 650  * control the output of kernel symbols.
 651  */
 652 #define TRACE_ITER_SYM_MASK \
 653         (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
 654
 655 extern struct tracer nop_trace;
 656
 657 /**
 658  * ftrace_preempt_disable - disable preemption scheduler safe
 659  *
 660  * When tracing can happen inside the scheduler, there exists
 661  * cases that the tracing might happen before the need_resched
 662  * flag is checked. If this happens and the tracer calls
 663  * preempt_enable (after a disable), a schedule might take place
 664  * causing an infinite recursion.
 665  *
 666  * To prevent this, we read the need_resched flag before
 667  * disabling preemption. When we want to enable preemption we
 668  * check the flag, if it is set, then we call preempt_enable_no_resched.
 669  * Otherwise, we call preempt_enable.
 670  *
 671  * The rational for doing the above is that if need_resched is set
 672  * and we have yet to reschedule, we are either in an atomic location
 673  * (where we do not need to check for scheduling) or we are inside
 674  * the scheduler and do not want to resched.
 675  */
 676 static inline int ftrace_preempt_disable(void)
 677 {
 678         int resched;
 679
 680         resched = need_resched();
 681         preempt_disable_notrace();
 682
 683         return resched;
 684 }
 685
 686 /**
 687  * ftrace_preempt_enable - enable preemption scheduler safe
 688  * @resched: the return value from ftrace_preempt_disable
 689  *
 690  * This is a scheduler safe way to enable preemption and not miss
 691  * any preemption checks. The disabled saved the state of preemption.
 692  * If resched is set, then we are either inside an atomic or
 693  * are inside the scheduler (we would have already scheduled
 694  * otherwise). In this case, we do not want to call normal
 695  * preempt_enable, but preempt_enable_no_resched instead.
 696  */
 697 static inline void ftrace_preempt_enable(int resched)
 698 {
 699         if (resched)
 700                 preempt_enable_no_resched_notrace();
 701         else
 702                 preempt_enable_notrace();
 703 }
 704
 705 #ifdef CONFIG_BRANCH_TRACER
 706 extern int enable_branch_tracing(struct trace_array *tr);
 707 extern void disable_branch_tracing(void);
 708 static inline int trace_branch_enable(struct trace_array *tr)
 709 {
 710         if (trace_flags & TRACE_ITER_BRANCH)
 711                 return enable_branch_tracing(tr);
 712         return 0;
 713 }
 714 static inline void trace_branch_disable(void)
 715 {
 716         /* due to races, always disable */
 717         disable_branch_tracing();
 718 }
 719 #else
 720 static inline int trace_branch_enable(struct trace_array *tr)
 721 {
 722         return 0;
 723 }
 724 static inline void trace_branch_disable(void)
 725 {
 726 }
 727 #endif /* CONFIG_BRANCH_TRACER */
 728
 729 /* set ring buffers to default size if not already done so */
 730 int tracing_update_buffers(void);
 731
 732 /* trace event type bit fields, not numeric */
 733 enum {
 734         TRACE_EVENT_TYPE_PRINTF         = 1,
 735         TRACE_EVENT_TYPE_RAW            = 2,
 736 };
 737
 738 struct ftrace_event_field {
 739         struct list_head        link;
 740         char                    *name;
 741         char                    *type;
 742         int                     filter_type;
 743         int                     offset;
 744         int                     size;
 745         int                     is_signed;
 746 };
 747
 748 struct event_filter {
 749         int                     n_preds;
 750         struct filter_pred      **preds;
 751         char                    *filter_string;
 752         bool                    no_reset;
 753 };
 754
 755 struct event_subsystem {
 756         struct list_head        list;
 757         const char              *name;
 758         struct dentry           *entry;
 759         struct event_filter     *filter;
 760         int                     nr_events;
 761 };
 762
 763 struct filter_pred;
 764
 765 typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event,
 766                                  int val1, int val2);
 767
 768 struct filter_pred {
 769         filter_pred_fn_t fn;
 770         u64 val;
 771         char str_val[MAX_FILTER_STR_VAL];
 772         int str_len;
 773         char *field_name;
 774         int offset;
 775         int not;
 776         int op;
 777         int pop_n;
 778 };
 779
 780 extern void print_event_filter(struct ftrace_event_call *call,
 781                                struct trace_seq *s);
 782 extern int apply_event_filter(struct ftrace_event_call *call,
 783                               char *filter_string);
 784 extern int apply_subsystem_event_filter(struct event_subsystem *system,
 785                                         char *filter_string);
 786 extern void print_subsystem_event_filter(struct event_subsystem *system,
 787                                          struct trace_seq *s);
 788 extern int filter_assign_type(const char *type);
 789
 790 static inline int
 791 filter_check_discard(struct ftrace_event_call *call, void *rec,
 792                      struct ring_buffer *buffer,
 793                      struct ring_buffer_event *event)
 794 {
 795         if (unlikely(call->filter_active) && !filter_match_preds(call, rec)) {
 796                 ring_buffer_discard_commit(buffer, event);
 797                 return 1;
 798         }
 799
 800         return 0;
 801 }
 802
 803 extern struct mutex event_mutex;
 804 extern struct list_head ftrace_events;
 805
 806 extern const char *__start___trace_bprintk_fmt[];
 807 extern const char *__stop___trace_bprintk_fmt[];
 808
 809 #undef TRACE_EVENT_FORMAT
 810 #define TRACE_EVENT_FORMAT(call, proto, args, fmt, tstruct, tpfmt)      \
 811         extern struct ftrace_event_call event_##call;
 812 #undef TRACE_EVENT_FORMAT_NOFILTER
 813 #define TRACE_EVENT_FORMAT_NOFILTER(call, proto, args, fmt, tstruct, tpfmt)
 814 #include "trace_event_types.h"
 815
 816 #endif /* _LINUX_KERNEL_TRACE_H */