kernel/trace/trace.h

   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/tracepoint.h>
  11 #include <linux/ftrace.h>
  12 #include <linux/kmemtrace.h>
  13 #include <linux/hw_breakpoint.h>
  14 #include <linux/trace_seq.h>
  15 #include <linux/ftrace_event.h>
  16
  17 enum trace_type {
  18         __TRACE_FIRST_TYPE = 0,
  19
  20         TRACE_FN,
  21         TRACE_CTX,
  22         TRACE_WAKE,
  23         TRACE_STACK,
  24         TRACE_PRINT,
  25         TRACE_BPRINT,
  26         TRACE_SPECIAL,
  27         TRACE_MMIO_RW,
  28         TRACE_MMIO_MAP,
  29         TRACE_BRANCH,
  30         TRACE_GRAPH_RET,
  31         TRACE_GRAPH_ENT,
  32         TRACE_USER_STACK,
  33         TRACE_KMEM_ALLOC,
  34         TRACE_KMEM_FREE,
  35         TRACE_BLK,
  36         TRACE_KSYM,
  37
  38         __TRACE_LAST_TYPE,
  39 };
  40
  41 enum kmemtrace_type_id {
  42         KMEMTRACE_TYPE_KMALLOC = 0,     /* kmalloc() or kfree(). */
  43         KMEMTRACE_TYPE_CACHE,           /* kmem_cache_*(). */
  44         KMEMTRACE_TYPE_PAGES,           /* __get_free_pages() and friends. */
  45 };
  46
  47 #undef __field
  48 #define __field(type, item)             type    item;
  49
  50 #undef __field_struct
  51 #define __field_struct(type, item)      __field(type, item)
  52
  53 #undef __field_desc
  54 #define __field_desc(type, container, item)
  55
  56 #undef __array
  57 #define __array(type, item, size)       type    item[size];
  58
  59 #undef __array_desc
  60 #define __array_desc(type, container, item, size)
  61
  62 #undef __dynamic_array
  63 #define __dynamic_array(type, item)     type    item[];
  64
  65 #undef F_STRUCT
  66 #define F_STRUCT(args...)               args
  67
  68 #undef FTRACE_ENTRY
  69 #define FTRACE_ENTRY(name, struct_name, id, tstruct, print)     \
  70         struct struct_name {                                    \
  71                 struct trace_entry      ent;                    \
  72                 tstruct                                         \
  73         }
  74
  75 #undef TP_ARGS
  76 #define TP_ARGS(args...)        args
  77
  78 #undef FTRACE_ENTRY_DUP
  79 #define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk)
  80
  81 #include "trace_entries.h"
  82
  83 /*
  84  * syscalls are special, and need special handling, this is why
  85  * they are not included in trace_entries.h
  86  */
  87 struct syscall_trace_enter {
  88         struct trace_entry      ent;
  89         int                     nr;
  90         unsigned long           args[];
  91 };
  92
  93 struct syscall_trace_exit {
  94         struct trace_entry      ent;
  95         int                     nr;
  96         long                    ret;
  97 };
  98
  99 struct kprobe_trace_entry_head {
 100         struct trace_entry      ent;
 101         unsigned long           ip;
 102 };
 103
 104 struct kretprobe_trace_entry_head {
 105         struct trace_entry      ent;
 106         unsigned long           func;
 107         unsigned long           ret_ip;
 108 };
 109
 110 /*
 111  * trace_flag_type is an enumeration that holds different
 112  * states when a trace occurs. These are:
 113  *  IRQS_OFF            - interrupts were disabled
 114  *  IRQS_NOSUPPORT      - arch does not support irqs_disabled_flags
 115  *  NEED_RESCHED        - reschedule is requested
 116  *  HARDIRQ             - inside an interrupt handler
 117  *  SOFTIRQ             - inside a softirq handler
 118  */
 119 enum trace_flag_type {
 120         TRACE_FLAG_IRQS_OFF             = 0x01,
 121         TRACE_FLAG_IRQS_NOSUPPORT       = 0x02,
 122         TRACE_FLAG_NEED_RESCHED         = 0x04,
 123         TRACE_FLAG_HARDIRQ              = 0x08,
 124         TRACE_FLAG_SOFTIRQ              = 0x10,
 125 };
 126
 127 #define TRACE_BUF_SIZE          1024
 128
 129 /*
 130  * The CPU trace array - it consists of thousands of trace entries
 131  * plus some other descriptor data: (for example which task started
 132  * the trace, etc.)
 133  */
 134 struct trace_array_cpu {
 135         atomic_t                disabled;
 136         void                    *buffer_page;   /* ring buffer spare */
 137
 138         unsigned long           saved_latency;
 139         unsigned long           critical_start;
 140         unsigned long           critical_end;
 141         unsigned long           critical_sequence;
 142         unsigned long           nice;
 143         unsigned long           policy;
 144         unsigned long           rt_priority;
 145         unsigned long           skipped_entries;
 146         cycle_t                 preempt_timestamp;
 147         pid_t                   pid;
 148         uid_t                   uid;
 149         char                    comm[TASK_COMM_LEN];
 150 };
 151
 152 /*
 153  * The trace array - an array of per-CPU trace arrays. This is the
 154  * highest level data structure that individual tracers deal with.
 155  * They have on/off state as well:
 156  */
 157 struct trace_array {
 158         struct ring_buffer      *buffer;
 159         unsigned long           entries;
 160         int                     cpu;
 161         cycle_t                 time_start;
 162         struct task_struct      *waiter;
 163         struct trace_array_cpu  *data[NR_CPUS];
 164 };
 165
 166 #define FTRACE_CMP_TYPE(var, type) \
 167         __builtin_types_compatible_p(typeof(var), type *)
 168
 169 #undef IF_ASSIGN
 170 #define IF_ASSIGN(var, entry, etype, id)                \
 171         if (FTRACE_CMP_TYPE(var, etype)) {              \
 172                 var = (typeof(var))(entry);             \
 173                 WARN_ON(id && (entry)->type != id);     \
 174                 break;                                  \
 175         }
 176
 177 /* Will cause compile errors if type is not found. */
 178 extern void __ftrace_bad_type(void);
 179
 180 /*
 181  * The trace_assign_type is a verifier that the entry type is
 182  * the same as the type being assigned. To add new types simply
 183  * add a line with the following format:
 184  *
 185  * IF_ASSIGN(var, ent, type, id);
 186  *
 187  *  Where "type" is the trace type that includes the trace_entry
 188  *  as the "ent" item. And "id" is the trace identifier that is
 189  *  used in the trace_type enum.
 190  *
 191  *  If the type can have more than one id, then use zero.
 192  */
 193 #define trace_assign_type(var, ent)                                     \
 194         do {                                                            \
 195                 IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN);     \
 196                 IF_ASSIGN(var, ent, struct ctx_switch_entry, 0);        \
 197                 IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK);   \
 198                 IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
 199                 IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT);   \
 200                 IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT); \
 201                 IF_ASSIGN(var, ent, struct special_entry, 0);           \
 202                 IF_ASSIGN(var, ent, struct trace_mmiotrace_rw,          \
 203                           TRACE_MMIO_RW);                               \
 204                 IF_ASSIGN(var, ent, struct trace_mmiotrace_map,         \
 205                           TRACE_MMIO_MAP);                              \
 206                 IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
 207                 IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry,      \
 208                           TRACE_GRAPH_ENT);             \
 209                 IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry,      \
 210                           TRACE_GRAPH_RET);             \
 211                 IF_ASSIGN(var, ent, struct kmemtrace_alloc_entry,       \
 212                           TRACE_KMEM_ALLOC);    \
 213                 IF_ASSIGN(var, ent, struct kmemtrace_free_entry,        \
 214                           TRACE_KMEM_FREE);     \
 215                 IF_ASSIGN(var, ent, struct ksym_trace_entry, TRACE_KSYM);\
 216                 __ftrace_bad_type();                                    \
 217         } while (0)
 218
 219 /*
 220  * An option specific to a tracer. This is a boolean value.
 221  * The bit is the bit index that sets its value on the
 222  * flags value in struct tracer_flags.
 223  */
 224 struct tracer_opt {
 225         const char      *name; /* Will appear on the trace_options file */
 226         u32             bit; /* Mask assigned in val field in tracer_flags */
 227 };
 228
 229 /*
 230  * The set of specific options for a tracer. Your tracer
 231  * have to set the initial value of the flags val.
 232  */
 233 struct tracer_flags {
 234         u32                     val;
 235         struct tracer_opt       *opts;
 236 };
 237
 238 /* Makes more easy to define a tracer opt */
 239 #define TRACER_OPT(s, b)        .name = #s, .bit = b
 240
 241
 242 /**
 243  * struct tracer - a specific tracer and its callbacks to interact with debugfs
 244  * @name: the name chosen to select it on the available_tracers file
 245  * @init: called when one switches to this tracer (echo name > current_tracer)
 246  * @reset: called when one switches to another tracer
 247  * @start: called when tracing is unpaused (echo 1 > tracing_enabled)
 248  * @stop: called when tracing is paused (echo 0 > tracing_enabled)
 249  * @open: called when the trace file is opened
 250  * @pipe_open: called when the trace_pipe file is opened
 251  * @wait_pipe: override how the user waits for traces on trace_pipe
 252  * @close: called when the trace file is released
 253  * @pipe_close: called when the trace_pipe file is released
 254  * @read: override the default read callback on trace_pipe
 255  * @splice_read: override the default splice_read callback on trace_pipe
 256  * @selftest: selftest to run on boot (see trace_selftest.c)
 257  * @print_headers: override the first lines that describe your columns
 258  * @print_line: callback that prints a trace
 259  * @set_flag: signals one of your private flags changed (trace_options file)
 260  * @flags: your private flags
 261  */
 262 struct tracer {
 263         const char              *name;
 264         int                     (*init)(struct trace_array *tr);
 265         void                    (*reset)(struct trace_array *tr);
 266         void                    (*start)(struct trace_array *tr);
 267         void                    (*stop)(struct trace_array *tr);
 268         void                    (*open)(struct trace_iterator *iter);
 269         void                    (*pipe_open)(struct trace_iterator *iter);
 270         void                    (*wait_pipe)(struct trace_iterator *iter);
 271         void                    (*close)(struct trace_iterator *iter);
 272         void                    (*pipe_close)(struct trace_iterator *iter);
 273         ssize_t                 (*read)(struct trace_iterator *iter,
 274                                         struct file *filp, char __user *ubuf,
 275                                         size_t cnt, loff_t *ppos);
 276         ssize_t                 (*splice_read)(struct trace_iterator *iter,
 277                                                struct file *filp,
 278                                                loff_t *ppos,
 279                                                struct pipe_inode_info *pipe,
 280                                                size_t len,
 281                                                unsigned int flags);
 282 #ifdef CONFIG_FTRACE_STARTUP_TEST
 283         int                     (*selftest)(struct tracer *trace,
 284                                             struct trace_array *tr);
 285 #endif
 286         void                    (*print_header)(struct seq_file *m);
 287         enum print_line_t       (*print_line)(struct trace_iterator *iter);
 288         /* If you handled the flag setting, return 0 */
 289         int                     (*set_flag)(u32 old_flags, u32 bit, int set);
 290         struct tracer           *next;
 291         int                     print_max;
 292         struct tracer_flags     *flags;
 293 };
 294
 295
 296 #define TRACE_PIPE_ALL_CPU      -1
 297
 298 int tracer_init(struct tracer *t, struct trace_array *tr);
 299 int tracing_is_enabled(void);
 300 void trace_wake_up(void);
 301 void tracing_reset(struct trace_array *tr, int cpu);
 302 void tracing_reset_online_cpus(struct trace_array *tr);
 303 void tracing_reset_current(int cpu);
 304 void tracing_reset_current_online_cpus(void);
 305 int tracing_open_generic(struct inode *inode, struct file *filp);
 306 struct dentry *trace_create_file(const char *name,
 307                                  mode_t mode,
 308                                  struct dentry *parent,
 309                                  void *data,
 310                                  const struct file_operations *fops);
 311
 312 struct dentry *tracing_init_dentry(void);
 313 void init_tracer_sysprof_debugfs(struct dentry *d_tracer);
 314
 315 struct ring_buffer_event;
 316
 317 struct ring_buffer_event *
 318 trace_buffer_lock_reserve(struct ring_buffer *buffer,
 319                           int type,
 320                           unsigned long len,
 321                           unsigned long flags,
 322                           int pc);
 323 void trace_buffer_unlock_commit(struct ring_buffer *buffer,
 324                                 struct ring_buffer_event *event,
 325                                 unsigned long flags, int pc);
 326
 327 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
 328                                                 struct trace_array_cpu *data);
 329
 330 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
 331                                           int *ent_cpu, u64 *ent_ts);
 332
 333 void default_wait_pipe(struct trace_iterator *iter);
 334 void poll_wait_pipe(struct trace_iterator *iter);
 335
 336 void ftrace(struct trace_array *tr,
 337                             struct trace_array_cpu *data,
 338                             unsigned long ip,
 339                             unsigned long parent_ip,
 340                             unsigned long flags, int pc);
 341 void tracing_sched_switch_trace(struct trace_array *tr,
 342                                 struct task_struct *prev,
 343                                 struct task_struct *next,
 344                                 unsigned long flags, int pc);
 345
 346 void tracing_sched_wakeup_trace(struct trace_array *tr,
 347                                 struct task_struct *wakee,
 348                                 struct task_struct *cur,
 349                                 unsigned long flags, int pc);
 350 void trace_special(struct trace_array *tr,
 351                    struct trace_array_cpu *data,
 352                    unsigned long arg1,
 353                    unsigned long arg2,
 354                    unsigned long arg3, int pc);
 355 void trace_function(struct trace_array *tr,
 356                     unsigned long ip,
 357                     unsigned long parent_ip,
 358                     unsigned long flags, int pc);
 359 void trace_default_header(struct seq_file *m);
 360 void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
 361 int trace_empty(struct trace_iterator *iter);
 362
 363 void trace_graph_return(struct ftrace_graph_ret *trace);
 364 int trace_graph_entry(struct ftrace_graph_ent *trace);
 365 void set_graph_array(struct trace_array *tr);
 366
 367 void tracing_start_cmdline_record(void);
 368 void tracing_stop_cmdline_record(void);
 369 void tracing_sched_switch_assign_trace(struct trace_array *tr);
 370 void tracing_stop_sched_switch_record(void);
 371 void tracing_start_sched_switch_record(void);
 372 int register_tracer(struct tracer *type);
 373 void unregister_tracer(struct tracer *type);
 374 int is_tracing_stopped(void);
 375
 376 extern int process_new_ksym_entry(char *ksymname, int op, unsigned long addr);
 377
 378 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
 379
 380 extern unsigned long tracing_thresh;
 381
 382 #ifdef CONFIG_TRACER_MAX_TRACE
 383 extern unsigned long tracing_max_latency;
 384
 385 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu);
 386 void update_max_tr_single(struct trace_array *tr,
 387                           struct task_struct *tsk, int cpu);
 388 #endif /* CONFIG_TRACER_MAX_TRACE */
 389
 390 #ifdef CONFIG_STACKTRACE
 391 void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags,
 392                         int skip, int pc);
 393
 394 void ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags,
 395                             int pc);
 396
 397 void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
 398                    int pc);
 399 #else
 400 static inline void ftrace_trace_stack(struct ring_buffer *buffer,
 401                                       unsigned long flags, int skip, int pc)
 402 {
 403 }
 404
 405 static inline void ftrace_trace_userstack(struct ring_buffer *buffer,
 406                                           unsigned long flags, int pc)
 407 {
 408 }
 409
 410 static inline void __trace_stack(struct trace_array *tr, unsigned long flags,
 411                                  int skip, int pc)
 412 {
 413 }
 414 #endif /* CONFIG_STACKTRACE */
 415
 416 extern cycle_t ftrace_now(int cpu);
 417
 418 extern void trace_find_cmdline(int pid, char comm[]);
 419
 420 #ifdef CONFIG_DYNAMIC_FTRACE
 421 extern unsigned long ftrace_update_tot_cnt;
 422 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
 423 extern int DYN_FTRACE_TEST_NAME(void);
 424 #endif
 425
 426 extern int ring_buffer_expanded;
 427 extern bool tracing_selftest_disabled;
 428 DECLARE_PER_CPU(int, ftrace_cpu_disabled);
 429
 430 #ifdef CONFIG_FTRACE_STARTUP_TEST
 431 extern int trace_selftest_startup_function(struct tracer *trace,
 432                                            struct trace_array *tr);
 433 extern int trace_selftest_startup_function_graph(struct tracer *trace,
 434                                                  struct trace_array *tr);
 435 extern int trace_selftest_startup_irqsoff(struct tracer *trace,
 436                                           struct trace_array *tr);
 437 extern int trace_selftest_startup_preemptoff(struct tracer *trace,
 438                                              struct trace_array *tr);
 439 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
 440                                                  struct trace_array *tr);
 441 extern int trace_selftest_startup_wakeup(struct tracer *trace,
 442                                          struct trace_array *tr);
 443 extern int trace_selftest_startup_nop(struct tracer *trace,
 444                                          struct trace_array *tr);
 445 extern int trace_selftest_startup_sched_switch(struct tracer *trace,
 446                                                struct trace_array *tr);
 447 extern int trace_selftest_startup_sysprof(struct tracer *trace,
 448                                                struct trace_array *tr);
 449 extern int trace_selftest_startup_branch(struct tracer *trace,
 450                                          struct trace_array *tr);
 451 extern int trace_selftest_startup_ksym(struct tracer *trace,
 452                                          struct trace_array *tr);
 453 #endif /* CONFIG_FTRACE_STARTUP_TEST */
 454
 455 extern void *head_page(struct trace_array_cpu *data);
 456 extern unsigned long long ns2usecs(cycle_t nsec);
 457 extern int
 458 trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
 459 extern int
 460 trace_vprintk(unsigned long ip, const char *fmt, va_list args);
 461 extern int
 462 trace_array_vprintk(struct trace_array *tr,
 463                     unsigned long ip, const char *fmt, va_list args);
 464 int trace_array_printk(struct trace_array *tr,
 465                        unsigned long ip, const char *fmt, ...);
 466
 467 extern unsigned long trace_flags;
 468
 469 extern int trace_clock_id;
 470
 471 /* Standard output formatting function used for function return traces */
 472 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
 473
 474 /* Flag options */
 475 #define TRACE_GRAPH_PRINT_OVERRUN       0x1
 476 #define TRACE_GRAPH_PRINT_CPU           0x2
 477 #define TRACE_GRAPH_PRINT_OVERHEAD      0x4
 478 #define TRACE_GRAPH_PRINT_PROC          0x8
 479 #define TRACE_GRAPH_PRINT_DURATION      0x10
 480 #define TRACE_GRAPH_PRINT_ABS_TIME      0x20
 481
 482 extern enum print_line_t
 483 print_graph_function_flags(struct trace_iterator *iter, u32 flags);
 484 extern void print_graph_headers_flags(struct seq_file *s, u32 flags);
 485 extern enum print_line_t
 486 trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
 487 extern void graph_trace_open(struct trace_iterator *iter);
 488 extern void graph_trace_close(struct trace_iterator *iter);
 489 extern int __trace_graph_entry(struct trace_array *tr,
 490                                struct ftrace_graph_ent *trace,
 491                                unsigned long flags, int pc);
 492 extern void __trace_graph_return(struct trace_array *tr,
 493                                  struct ftrace_graph_ret *trace,
 494                                  unsigned long flags, int pc);
 495
 496
 497 #ifdef CONFIG_DYNAMIC_FTRACE
 498 /* TODO: make this variable */
 499 #define FTRACE_GRAPH_MAX_FUNCS          32
 500 extern int ftrace_graph_filter_enabled;
 501 extern int ftrace_graph_count;
 502 extern unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS];
 503
 504 static inline int ftrace_graph_addr(unsigned long addr)
 505 {
 506         int i;
 507
 508         if (!ftrace_graph_filter_enabled)
 509                 return 1;
 510
 511         for (i = 0; i < ftrace_graph_count; i++) {
 512                 if (addr == ftrace_graph_funcs[i])
 513                         return 1;
 514         }
 515
 516         return 0;
 517 }
 518 #else
 519 static inline int ftrace_graph_addr(unsigned long addr)
 520 {
 521         return 1;
 522 }
 523 #endif /* CONFIG_DYNAMIC_FTRACE */
 524 #else /* CONFIG_FUNCTION_GRAPH_TRACER */
 525 static inline enum print_line_t
 526 print_graph_function_flags(struct trace_iterator *iter, u32 flags)
 527 {
 528         return TRACE_TYPE_UNHANDLED;
 529 }
 530 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
 531
 532 extern struct list_head ftrace_pids;
 533
 534 #ifdef CONFIG_FUNCTION_TRACER
 535 static inline int ftrace_trace_task(struct task_struct *task)
 536 {
 537         if (list_empty(&ftrace_pids))
 538                 return 1;
 539
 540         return test_tsk_trace_trace(task);
 541 }
 542 #else
 543 static inline int ftrace_trace_task(struct task_struct *task)
 544 {
 545         return 1;
 546 }
 547 #endif
 548
 549 /*
 550  * struct trace_parser - servers for reading the user input separated by spaces
 551  * @cont: set if the input is not complete - no final space char was found
 552  * @buffer: holds the parsed user input
 553  * @idx: user input length
 554  * @size: buffer size
 555  */
 556 struct trace_parser {
 557         bool            cont;
 558         char            *buffer;
 559         unsigned        idx;
 560         unsigned        size;
 561 };
 562
 563 static inline bool trace_parser_loaded(struct trace_parser *parser)
 564 {
 565         return (parser->idx != 0);
 566 }
 567
 568 static inline bool trace_parser_cont(struct trace_parser *parser)
 569 {
 570         return parser->cont;
 571 }
 572
 573 static inline void trace_parser_clear(struct trace_parser *parser)
 574 {
 575         parser->cont = false;
 576         parser->idx = 0;
 577 }
 578
 579 extern int trace_parser_get_init(struct trace_parser *parser, int size);
 580 extern void trace_parser_put(struct trace_parser *parser);
 581 extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
 582         size_t cnt, loff_t *ppos);
 583
 584 /*
 585  * trace_iterator_flags is an enumeration that defines bit
 586  * positions into trace_flags that controls the output.
 587  *
 588  * NOTE: These bits must match the trace_options array in
 589  *       trace.c.
 590  */
 591 enum trace_iterator_flags {
 592         TRACE_ITER_PRINT_PARENT         = 0x01,
 593         TRACE_ITER_SYM_OFFSET           = 0x02,
 594         TRACE_ITER_SYM_ADDR             = 0x04,
 595         TRACE_ITER_VERBOSE              = 0x08,
 596         TRACE_ITER_RAW                  = 0x10,
 597         TRACE_ITER_HEX                  = 0x20,
 598         TRACE_ITER_BIN                  = 0x40,
 599         TRACE_ITER_BLOCK                = 0x80,
 600         TRACE_ITER_STACKTRACE           = 0x100,
 601         TRACE_ITER_PRINTK               = 0x200,
 602         TRACE_ITER_PREEMPTONLY          = 0x400,
 603         TRACE_ITER_BRANCH               = 0x800,
 604         TRACE_ITER_ANNOTATE             = 0x1000,
 605         TRACE_ITER_USERSTACKTRACE       = 0x2000,
 606         TRACE_ITER_SYM_USEROBJ          = 0x4000,
 607         TRACE_ITER_PRINTK_MSGONLY       = 0x8000,
 608         TRACE_ITER_CONTEXT_INFO         = 0x10000, /* Print pid/cpu/time */
 609         TRACE_ITER_LATENCY_FMT          = 0x20000,
 610         TRACE_ITER_SLEEP_TIME           = 0x40000,
 611         TRACE_ITER_GRAPH_TIME           = 0x80000,
 612 };
 613
 614 /*
 615  * TRACE_ITER_SYM_MASK masks the options in trace_flags that
 616  * control the output of kernel symbols.
 617  */
 618 #define TRACE_ITER_SYM_MASK \
 619         (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
 620
 621 extern struct tracer nop_trace;
 622
 623 /**
 624  * ftrace_preempt_disable - disable preemption scheduler safe
 625  *
 626  * When tracing can happen inside the scheduler, there exists
 627  * cases that the tracing might happen before the need_resched
 628  * flag is checked. If this happens and the tracer calls
 629  * preempt_enable (after a disable), a schedule might take place
 630  * causing an infinite recursion.
 631  *
 632  * To prevent this, we read the need_resched flag before
 633  * disabling preemption. When we want to enable preemption we
 634  * check the flag, if it is set, then we call preempt_enable_no_resched.
 635  * Otherwise, we call preempt_enable.
 636  *
 637  * The rational for doing the above is that if need_resched is set
 638  * and we have yet to reschedule, we are either in an atomic location
 639  * (where we do not need to check for scheduling) or we are inside
 640  * the scheduler and do not want to resched.
 641  */
 642 static inline int ftrace_preempt_disable(void)
 643 {
 644         int resched;
 645
 646         resched = need_resched();
 647         preempt_disable_notrace();
 648
 649         return resched;
 650 }
 651
 652 /**
 653  * ftrace_preempt_enable - enable preemption scheduler safe
 654  * @resched: the return value from ftrace_preempt_disable
 655  *
 656  * This is a scheduler safe way to enable preemption and not miss
 657  * any preemption checks. The disabled saved the state of preemption.
 658  * If resched is set, then we are either inside an atomic or
 659  * are inside the scheduler (we would have already scheduled
 660  * otherwise). In this case, we do not want to call normal
 661  * preempt_enable, but preempt_enable_no_resched instead.
 662  */
 663 static inline void ftrace_preempt_enable(int resched)
 664 {
 665         if (resched)
 666                 preempt_enable_no_resched_notrace();
 667         else
 668                 preempt_enable_notrace();
 669 }
 670
 671 #ifdef CONFIG_BRANCH_TRACER
 672 extern int enable_branch_tracing(struct trace_array *tr);
 673 extern void disable_branch_tracing(void);
 674 static inline int trace_branch_enable(struct trace_array *tr)
 675 {
 676         if (trace_flags & TRACE_ITER_BRANCH)
 677                 return enable_branch_tracing(tr);
 678         return 0;
 679 }
 680 static inline void trace_branch_disable(void)
 681 {
 682         /* due to races, always disable */
 683         disable_branch_tracing();
 684 }
 685 #else
 686 static inline int trace_branch_enable(struct trace_array *tr)
 687 {
 688         return 0;
 689 }
 690 static inline void trace_branch_disable(void)
 691 {
 692 }
 693 #endif /* CONFIG_BRANCH_TRACER */
 694
 695 /* set ring buffers to default size if not already done so */
 696 int tracing_update_buffers(void);
 697
 698 /* trace event type bit fields, not numeric */
 699 enum {
 700         TRACE_EVENT_TYPE_PRINTF         = 1,
 701         TRACE_EVENT_TYPE_RAW            = 2,
 702 };
 703
 704 struct ftrace_event_field {
 705         struct list_head        link;
 706         char                    *name;
 707         char                    *type;
 708         int                     filter_type;
 709         int                     offset;
 710         int                     size;
 711         int                     is_signed;
 712 };
 713
 714 struct event_filter {
 715         int                     n_preds;
 716         struct filter_pred      **preds;
 717         char                    *filter_string;
 718 };
 719
 720 struct event_subsystem {
 721         struct list_head        list;
 722         const char              *name;
 723         struct dentry           *entry;
 724         struct event_filter     *filter;
 725         int                     nr_events;
 726 };
 727
 728 struct filter_pred;
 729 struct regex;
 730
 731 typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event,
 732                                  int val1, int val2);
 733
 734 typedef int (*regex_match_func)(char *str, struct regex *r, int len);
 735
 736 enum regex_type {
 737         MATCH_FULL = 0,
 738         MATCH_FRONT_ONLY,
 739         MATCH_MIDDLE_ONLY,
 740         MATCH_END_ONLY,
 741 };
 742
 743 struct regex {
 744         char                    pattern[MAX_FILTER_STR_VAL];
 745         int                     len;
 746         int                     field_len;
 747         regex_match_func        match;
 748 };
 749
 750 struct filter_pred {
 751         filter_pred_fn_t        fn;
 752         u64                     val;
 753         struct regex            regex;
 754         char                    *field_name;
 755         int                     offset;
 756         int                     not;
 757         int                     op;
 758         int                     pop_n;
 759 };
 760
 761 extern enum regex_type
 762 filter_parse_regex(char *buff, int len, char **search, int *not);
 763 extern void print_event_filter(struct ftrace_event_call *call,
 764                                struct trace_seq *s);
 765 extern int apply_event_filter(struct ftrace_event_call *call,
 766                               char *filter_string);
 767 extern int apply_subsystem_event_filter(struct event_subsystem *system,
 768                                         char *filter_string);
 769 extern void print_subsystem_event_filter(struct event_subsystem *system,
 770                                          struct trace_seq *s);
 771 extern int filter_assign_type(const char *type);
 772
 773 struct list_head *
 774 trace_get_fields(struct ftrace_event_call *event_call);
 775
 776 static inline int
 777 filter_check_discard(struct ftrace_event_call *call, void *rec,
 778                      struct ring_buffer *buffer,
 779                      struct ring_buffer_event *event)
 780 {
 781         if (unlikely(call->flags & TRACE_EVENT_FL_FILTERED) &&
 782             !filter_match_preds(call->filter, rec)) {
 783                 ring_buffer_discard_commit(buffer, event);
 784                 return 1;
 785         }
 786
 787         return 0;
 788 }
 789
 790 extern struct mutex event_mutex;
 791 extern struct list_head ftrace_events;
 792
 793 extern const char *__start___trace_bprintk_fmt[];
 794 extern const char *__stop___trace_bprintk_fmt[];
 795
 796 #undef FTRACE_ENTRY
 797 #define FTRACE_ENTRY(call, struct_name, id, tstruct, print)             \
 798         extern struct ftrace_event_call                                 \
 799         __attribute__((__aligned__(4))) event_##call;
 800 #undef FTRACE_ENTRY_DUP
 801 #define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print)         \
 802         FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
 803 #include "trace_entries.h"
 804
 805 #endif /* _LINUX_KERNEL_TRACE_H */