kernel/trace/trace.h

   1 #ifndef _LINUX_KERNEL_TRACE_H
   2 #define _LINUX_KERNEL_TRACE_H
   3
   4 #include <linux/fs.h>
   5 #include <linux/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/hw_breakpoint.h>
  13 #include <linux/trace_seq.h>
  14 #include <linux/ftrace_event.h>
  15
  16 enum trace_type {
  17         __TRACE_FIRST_TYPE = 0,
  18
  19         TRACE_FN,
  20         TRACE_CTX,
  21         TRACE_WAKE,
  22         TRACE_STACK,
  23         TRACE_PRINT,
  24         TRACE_BPRINT,
  25         TRACE_MMIO_RW,
  26         TRACE_MMIO_MAP,
  27         TRACE_BRANCH,
  28         TRACE_GRAPH_RET,
  29         TRACE_GRAPH_ENT,
  30         TRACE_USER_STACK,
  31         TRACE_BLK,
  32
  33         __TRACE_LAST_TYPE,
  34 };
  35
  36
  37 #undef __field
  38 #define __field(type, item)             type    item;
  39
  40 #undef __field_struct
  41 #define __field_struct(type, item)      __field(type, item)
  42
  43 #undef __field_desc
  44 #define __field_desc(type, container, item)
  45
  46 #undef __array
  47 #define __array(type, item, size)       type    item[size];
  48
  49 #undef __array_desc
  50 #define __array_desc(type, container, item, size)
  51
  52 #undef __dynamic_array
  53 #define __dynamic_array(type, item)     type    item[];
  54
  55 #undef F_STRUCT
  56 #define F_STRUCT(args...)               args
  57
  58 #undef FTRACE_ENTRY
  59 #define FTRACE_ENTRY(name, struct_name, id, tstruct, print)     \
  60         struct struct_name {                                    \
  61                 struct trace_entry      ent;                    \
  62                 tstruct                                         \
  63         }
  64
  65 #undef TP_ARGS
  66 #define TP_ARGS(args...)        args
  67
  68 #undef FTRACE_ENTRY_DUP
  69 #define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk)
  70
  71 #include "trace_entries.h"
  72
  73 /*
  74  * syscalls are special, and need special handling, this is why
  75  * they are not included in trace_entries.h
  76  */
  77 struct syscall_trace_enter {
  78         struct trace_entry      ent;
  79         int                     nr;
  80         unsigned long           args[];
  81 };
  82
  83 struct syscall_trace_exit {
  84         struct trace_entry      ent;
  85         int                     nr;
  86         long                    ret;
  87 };
  88
  89 struct kprobe_trace_entry_head {
  90         struct trace_entry      ent;
  91         unsigned long           ip;
  92 };
  93
  94 struct kretprobe_trace_entry_head {
  95         struct trace_entry      ent;
  96         unsigned long           func;
  97         unsigned long           ret_ip;
  98 };
  99
 100 /*
 101  * trace_flag_type is an enumeration that holds different
 102  * states when a trace occurs. These are:
 103  *  IRQS_OFF            - interrupts were disabled
 104  *  IRQS_NOSUPPORT      - arch does not support irqs_disabled_flags
 105  *  NEED_RESCHED        - reschedule is requested
 106  *  HARDIRQ             - inside an interrupt handler
 107  *  SOFTIRQ             - inside a softirq handler
 108  */
 109 enum trace_flag_type {
 110         TRACE_FLAG_IRQS_OFF             = 0x01,
 111         TRACE_FLAG_IRQS_NOSUPPORT       = 0x02,
 112         TRACE_FLAG_NEED_RESCHED         = 0x04,
 113         TRACE_FLAG_HARDIRQ              = 0x08,
 114         TRACE_FLAG_SOFTIRQ              = 0x10,
 115 };
 116
 117 #define TRACE_BUF_SIZE          1024
 118
 119 /*
 120  * The CPU trace array - it consists of thousands of trace entries
 121  * plus some other descriptor data: (for example which task started
 122  * the trace, etc.)
 123  */
 124 struct trace_array_cpu {
 125         atomic_t                disabled;
 126         void                    *buffer_page;   /* ring buffer spare */
 127
 128         unsigned long           saved_latency;
 129         unsigned long           critical_start;
 130         unsigned long           critical_end;
 131         unsigned long           critical_sequence;
 132         unsigned long           nice;
 133         unsigned long           policy;
 134         unsigned long           rt_priority;
 135         unsigned long           skipped_entries;
 136         cycle_t                 preempt_timestamp;
 137         pid_t                   pid;
 138         uid_t                   uid;
 139         char                    comm[TASK_COMM_LEN];
 140 };
 141
 142 /*
 143  * The trace array - an array of per-CPU trace arrays. This is the
 144  * highest level data structure that individual tracers deal with.
 145  * They have on/off state as well:
 146  */
 147 struct trace_array {
 148         struct ring_buffer      *buffer;
 149         unsigned long           entries;
 150         int                     cpu;
 151         cycle_t                 time_start;
 152         struct task_struct      *waiter;
 153         struct trace_array_cpu  *data[NR_CPUS];
 154 };
 155
 156 #define FTRACE_CMP_TYPE(var, type) \
 157         __builtin_types_compatible_p(typeof(var), type *)
 158
 159 #undef IF_ASSIGN
 160 #define IF_ASSIGN(var, entry, etype, id)                \
 161         if (FTRACE_CMP_TYPE(var, etype)) {              \
 162                 var = (typeof(var))(entry);             \
 163                 WARN_ON(id && (entry)->type != id);     \
 164                 break;                                  \
 165         }
 166
 167 /* Will cause compile errors if type is not found. */
 168 extern void __ftrace_bad_type(void);
 169
 170 /*
 171  * The trace_assign_type is a verifier that the entry type is
 172  * the same as the type being assigned. To add new types simply
 173  * add a line with the following format:
 174  *
 175  * IF_ASSIGN(var, ent, type, id);
 176  *
 177  *  Where "type" is the trace type that includes the trace_entry
 178  *  as the "ent" item. And "id" is the trace identifier that is
 179  *  used in the trace_type enum.
 180  *
 181  *  If the type can have more than one id, then use zero.
 182  */
 183 #define trace_assign_type(var, ent)                                     \
 184         do {                                                            \
 185                 IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN);     \
 186                 IF_ASSIGN(var, ent, struct ctx_switch_entry, 0);        \
 187                 IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK);   \
 188                 IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
 189                 IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT);   \
 190                 IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT); \
 191                 IF_ASSIGN(var, ent, struct trace_mmiotrace_rw,          \
 192                           TRACE_MMIO_RW);                               \
 193                 IF_ASSIGN(var, ent, struct trace_mmiotrace_map,         \
 194                           TRACE_MMIO_MAP);                              \
 195                 IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
 196                 IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry,      \
 197                           TRACE_GRAPH_ENT);             \
 198                 IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry,      \
 199                           TRACE_GRAPH_RET);             \
 200                 __ftrace_bad_type();                                    \
 201         } while (0)
 202
 203 /*
 204  * An option specific to a tracer. This is a boolean value.
 205  * The bit is the bit index that sets its value on the
 206  * flags value in struct tracer_flags.
 207  */
 208 struct tracer_opt {
 209         const char      *name; /* Will appear on the trace_options file */
 210         u32             bit; /* Mask assigned in val field in tracer_flags */
 211 };
 212
 213 /*
 214  * The set of specific options for a tracer. Your tracer
 215  * have to set the initial value of the flags val.
 216  */
 217 struct tracer_flags {
 218         u32                     val;
 219         struct tracer_opt       *opts;
 220 };
 221
 222 /* Makes more easy to define a tracer opt */
 223 #define TRACER_OPT(s, b)        .name = #s, .bit = b
 224
 225
 226 /**
 227  * struct tracer - a specific tracer and its callbacks to interact with debugfs
 228  * @name: the name chosen to select it on the available_tracers file
 229  * @init: called when one switches to this tracer (echo name > current_tracer)
 230  * @reset: called when one switches to another tracer
 231  * @start: called when tracing is unpaused (echo 1 > tracing_enabled)
 232  * @stop: called when tracing is paused (echo 0 > tracing_enabled)
 233  * @open: called when the trace file is opened
 234  * @pipe_open: called when the trace_pipe file is opened
 235  * @wait_pipe: override how the user waits for traces on trace_pipe
 236  * @close: called when the trace file is released
 237  * @pipe_close: called when the trace_pipe file is released
 238  * @read: override the default read callback on trace_pipe
 239  * @splice_read: override the default splice_read callback on trace_pipe
 240  * @selftest: selftest to run on boot (see trace_selftest.c)
 241  * @print_headers: override the first lines that describe your columns
 242  * @print_line: callback that prints a trace
 243  * @set_flag: signals one of your private flags changed (trace_options file)
 244  * @flags: your private flags
 245  */
 246 struct tracer {
 247         const char              *name;
 248         int                     (*init)(struct trace_array *tr);
 249         void                    (*reset)(struct trace_array *tr);
 250         void                    (*start)(struct trace_array *tr);
 251         void                    (*stop)(struct trace_array *tr);
 252         void                    (*open)(struct trace_iterator *iter);
 253         void                    (*pipe_open)(struct trace_iterator *iter);
 254         void                    (*wait_pipe)(struct trace_iterator *iter);
 255         void                    (*close)(struct trace_iterator *iter);
 256         void                    (*pipe_close)(struct trace_iterator *iter);
 257         ssize_t                 (*read)(struct trace_iterator *iter,
 258                                         struct file *filp, char __user *ubuf,
 259                                         size_t cnt, loff_t *ppos);
 260         ssize_t                 (*splice_read)(struct trace_iterator *iter,
 261                                                struct file *filp,
 262                                                loff_t *ppos,
 263                                                struct pipe_inode_info *pipe,
 264                                                size_t len,
 265                                                unsigned int flags);
 266 #ifdef CONFIG_FTRACE_STARTUP_TEST
 267         int                     (*selftest)(struct tracer *trace,
 268                                             struct trace_array *tr);
 269 #endif
 270         void                    (*print_header)(struct seq_file *m);
 271         enum print_line_t       (*print_line)(struct trace_iterator *iter);
 272         /* If you handled the flag setting, return 0 */
 273         int                     (*set_flag)(u32 old_flags, u32 bit, int set);
 274         struct tracer           *next;
 275         struct tracer_flags     *flags;
 276         int                     print_max;
 277         int                     use_max_tr;
 278 };
 279
 280
 281 /* Only current can touch trace_recursion */
 282 #define trace_recursion_inc() do { (current)->trace_recursion++; } while (0)
 283 #define trace_recursion_dec() do { (current)->trace_recursion--; } while (0)
 284
 285 /* Ring buffer has the 10 LSB bits to count */
 286 #define trace_recursion_buffer() ((current)->trace_recursion & 0x3ff)
 287
 288 /* for function tracing recursion */
 289 #define TRACE_INTERNAL_BIT              (1<<11)
 290 #define TRACE_GLOBAL_BIT                (1<<12)
 291 /*
 292  * Abuse of the trace_recursion.
 293  * As we need a way to maintain state if we are tracing the function
 294  * graph in irq because we want to trace a particular function that
 295  * was called in irq context but we have irq tracing off. Since this
 296  * can only be modified by current, we can reuse trace_recursion.
 297  */
 298 #define TRACE_IRQ_BIT                   (1<<13)
 299
 300 #define trace_recursion_set(bit)        do { (current)->trace_recursion |= (bit); } while (0)
 301 #define trace_recursion_clear(bit)      do { (current)->trace_recursion &= ~(bit); } while (0)
 302 #define trace_recursion_test(bit)       ((current)->trace_recursion & (bit))
 303
 304 #define TRACE_PIPE_ALL_CPU      -1
 305
 306 int tracer_init(struct tracer *t, struct trace_array *tr);
 307 int tracing_is_enabled(void);
 308 void trace_wake_up(void);
 309 void tracing_reset(struct trace_array *tr, int cpu);
 310 void tracing_reset_online_cpus(struct trace_array *tr);
 311 void tracing_reset_current(int cpu);
 312 void tracing_reset_current_online_cpus(void);
 313 int tracing_open_generic(struct inode *inode, struct file *filp);
 314 struct dentry *trace_create_file(const char *name,
 315                                  mode_t mode,
 316                                  struct dentry *parent,
 317                                  void *data,
 318                                  const struct file_operations *fops);
 319
 320 struct dentry *tracing_init_dentry(void);
 321
 322 struct ring_buffer_event;
 323
 324 struct ring_buffer_event *
 325 trace_buffer_lock_reserve(struct ring_buffer *buffer,
 326                           int type,
 327                           unsigned long len,
 328                           unsigned long flags,
 329                           int pc);
 330 void trace_buffer_unlock_commit(struct ring_buffer *buffer,
 331                                 struct ring_buffer_event *event,
 332                                 unsigned long flags, int pc);
 333
 334 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
 335                                                 struct trace_array_cpu *data);
 336
 337 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
 338                                           int *ent_cpu, u64 *ent_ts);
 339
 340 int trace_empty(struct trace_iterator *iter);
 341
 342 void *trace_find_next_entry_inc(struct trace_iterator *iter);
 343
 344 void trace_init_global_iter(struct trace_iterator *iter);
 345
 346 void tracing_iter_reset(struct trace_iterator *iter, int cpu);
 347
 348 void default_wait_pipe(struct trace_iterator *iter);
 349 void poll_wait_pipe(struct trace_iterator *iter);
 350
 351 void ftrace(struct trace_array *tr,
 352                             struct trace_array_cpu *data,
 353                             unsigned long ip,
 354                             unsigned long parent_ip,
 355                             unsigned long flags, int pc);
 356 void tracing_sched_switch_trace(struct trace_array *tr,
 357                                 struct task_struct *prev,
 358                                 struct task_struct *next,
 359                                 unsigned long flags, int pc);
 360
 361 void tracing_sched_wakeup_trace(struct trace_array *tr,
 362                                 struct task_struct *wakee,
 363                                 struct task_struct *cur,
 364                                 unsigned long flags, int pc);
 365 void trace_function(struct trace_array *tr,
 366                     unsigned long ip,
 367                     unsigned long parent_ip,
 368                     unsigned long flags, int pc);
 369 void trace_graph_function(struct trace_array *tr,
 370                     unsigned long ip,
 371                     unsigned long parent_ip,
 372                     unsigned long flags, int pc);
 373 void trace_default_header(struct seq_file *m);
 374 void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
 375 int trace_empty(struct trace_iterator *iter);
 376
 377 void trace_graph_return(struct ftrace_graph_ret *trace);
 378 int trace_graph_entry(struct ftrace_graph_ent *trace);
 379 void set_graph_array(struct trace_array *tr);
 380
 381 void tracing_start_cmdline_record(void);
 382 void tracing_stop_cmdline_record(void);
 383 void tracing_sched_switch_assign_trace(struct trace_array *tr);
 384 void tracing_stop_sched_switch_record(void);
 385 void tracing_start_sched_switch_record(void);
 386 int register_tracer(struct tracer *type);
 387 void unregister_tracer(struct tracer *type);
 388 int is_tracing_stopped(void);
 389 enum trace_file_type {
 390         TRACE_FILE_LAT_FMT      = 1,
 391         TRACE_FILE_ANNOTATE     = 2,
 392 };
 393
 394 extern cpumask_var_t __read_mostly tracing_buffer_mask;
 395
 396 #define for_each_tracing_cpu(cpu)       \
 397         for_each_cpu(cpu, tracing_buffer_mask)
 398
 399 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
 400
 401 extern unsigned long tracing_thresh;
 402
 403 #ifdef CONFIG_TRACER_MAX_TRACE
 404 extern unsigned long tracing_max_latency;
 405
 406 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu);
 407 void update_max_tr_single(struct trace_array *tr,
 408                           struct task_struct *tsk, int cpu);
 409 #endif /* CONFIG_TRACER_MAX_TRACE */
 410
 411 #ifdef CONFIG_STACKTRACE
 412 void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags,
 413                         int skip, int pc);
 414
 415 void ftrace_trace_stack_regs(struct ring_buffer *buffer, unsigned long flags,
 416                              int skip, int pc, struct pt_regs *regs);
 417
 418 void ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags,
 419                             int pc);
 420
 421 void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
 422                    int pc);
 423 #else
 424 static inline void ftrace_trace_stack(struct ring_buffer *buffer,
 425                                       unsigned long flags, int skip, int pc)
 426 {
 427 }
 428
 429 static inline void ftrace_trace_stack_regs(struct ring_buffer *buffer,
 430                                            unsigned long flags, int skip,
 431                                            int pc, struct pt_regs *regs)
 432 {
 433 }
 434
 435 static inline void ftrace_trace_userstack(struct ring_buffer *buffer,
 436                                           unsigned long flags, int pc)
 437 {
 438 }
 439
 440 static inline void __trace_stack(struct trace_array *tr, unsigned long flags,
 441                                  int skip, int pc)
 442 {
 443 }
 444 #endif /* CONFIG_STACKTRACE */
 445
 446 extern cycle_t ftrace_now(int cpu);
 447
 448 extern void trace_find_cmdline(int pid, char comm[]);
 449
 450 #ifdef CONFIG_DYNAMIC_FTRACE
 451 extern unsigned long ftrace_update_tot_cnt;
 452 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
 453 extern int DYN_FTRACE_TEST_NAME(void);
 454 #define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
 455 extern int DYN_FTRACE_TEST_NAME2(void);
 456 #endif
 457
 458 extern int ring_buffer_expanded;
 459 extern bool tracing_selftest_disabled;
 460 DECLARE_PER_CPU(int, ftrace_cpu_disabled);
 461
 462 #ifdef CONFIG_FTRACE_STARTUP_TEST
 463 extern int trace_selftest_startup_function(struct tracer *trace,
 464                                            struct trace_array *tr);
 465 extern int trace_selftest_startup_function_graph(struct tracer *trace,
 466                                                  struct trace_array *tr);
 467 extern int trace_selftest_startup_irqsoff(struct tracer *trace,
 468                                           struct trace_array *tr);
 469 extern int trace_selftest_startup_preemptoff(struct tracer *trace,
 470                                              struct trace_array *tr);
 471 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
 472                                                  struct trace_array *tr);
 473 extern int trace_selftest_startup_wakeup(struct tracer *trace,
 474                                          struct trace_array *tr);
 475 extern int trace_selftest_startup_nop(struct tracer *trace,
 476                                          struct trace_array *tr);
 477 extern int trace_selftest_startup_sched_switch(struct tracer *trace,
 478                                                struct trace_array *tr);
 479 extern int trace_selftest_startup_branch(struct tracer *trace,
 480                                          struct trace_array *tr);
 481 #endif /* CONFIG_FTRACE_STARTUP_TEST */
 482
 483 extern void *head_page(struct trace_array_cpu *data);
 484 extern unsigned long long ns2usecs(cycle_t nsec);
 485 extern int
 486 trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
 487 extern int
 488 trace_vprintk(unsigned long ip, const char *fmt, va_list args);
 489 extern int
 490 trace_array_vprintk(struct trace_array *tr,
 491                     unsigned long ip, const char *fmt, va_list args);
 492 int trace_array_printk(struct trace_array *tr,
 493                        unsigned long ip, const char *fmt, ...);
 494 void trace_printk_seq(struct trace_seq *s);
 495 enum print_line_t print_trace_line(struct trace_iterator *iter);
 496
 497 extern unsigned long trace_flags;
 498
 499 extern int trace_clock_id;
 500
 501 /* Standard output formatting function used for function return traces */
 502 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
 503
 504 /* Flag options */
 505 #define TRACE_GRAPH_PRINT_OVERRUN       0x1
 506 #define TRACE_GRAPH_PRINT_CPU           0x2
 507 #define TRACE_GRAPH_PRINT_OVERHEAD      0x4
 508 #define TRACE_GRAPH_PRINT_PROC          0x8
 509 #define TRACE_GRAPH_PRINT_DURATION      0x10
 510 #define TRACE_GRAPH_PRINT_ABS_TIME      0x20
 511
 512 extern enum print_line_t
 513 print_graph_function_flags(struct trace_iterator *iter, u32 flags);
 514 extern void print_graph_headers_flags(struct seq_file *s, u32 flags);
 515 extern enum print_line_t
 516 trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
 517 extern void graph_trace_open(struct trace_iterator *iter);
 518 extern void graph_trace_close(struct trace_iterator *iter);
 519 extern int __trace_graph_entry(struct trace_array *tr,
 520                                struct ftrace_graph_ent *trace,
 521                                unsigned long flags, int pc);
 522 extern void __trace_graph_return(struct trace_array *tr,
 523                                  struct ftrace_graph_ret *trace,
 524                                  unsigned long flags, int pc);
 525
 526
 527 #ifdef CONFIG_DYNAMIC_FTRACE
 528 /* TODO: make this variable */
 529 #define FTRACE_GRAPH_MAX_FUNCS          32
 530 extern int ftrace_graph_filter_enabled;
 531 extern int ftrace_graph_count;
 532 extern unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS];
 533
 534 static inline int ftrace_graph_addr(unsigned long addr)
 535 {
 536         int i;
 537
 538         if (!ftrace_graph_filter_enabled)
 539                 return 1;
 540
 541         for (i = 0; i < ftrace_graph_count; i++) {
 542                 if (addr == ftrace_graph_funcs[i]) {
 543                         /*
 544                          * If no irqs are to be traced, but a set_graph_function
 545                          * is set, and called by an interrupt handler, we still
 546                          * want to trace it.
 547                          */
 548                         if (in_irq())
 549                                 trace_recursion_set(TRACE_IRQ_BIT);
 550                         else
 551                                 trace_recursion_clear(TRACE_IRQ_BIT);
 552                         return 1;
 553                 }
 554         }
 555
 556         return 0;
 557 }
 558 #else
 559 static inline int ftrace_graph_addr(unsigned long addr)
 560 {
 561         return 1;
 562 }
 563 #endif /* CONFIG_DYNAMIC_FTRACE */
 564 #else /* CONFIG_FUNCTION_GRAPH_TRACER */
 565 static inline enum print_line_t
 566 print_graph_function_flags(struct trace_iterator *iter, u32 flags)
 567 {
 568         return TRACE_TYPE_UNHANDLED;
 569 }
 570 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
 571
 572 extern struct list_head ftrace_pids;
 573
 574 #ifdef CONFIG_FUNCTION_TRACER
 575 static inline int ftrace_trace_task(struct task_struct *task)
 576 {
 577         if (list_empty(&ftrace_pids))
 578                 return 1;
 579
 580         return test_tsk_trace_trace(task);
 581 }
 582 #else
 583 static inline int ftrace_trace_task(struct task_struct *task)
 584 {
 585         return 1;
 586 }
 587 #endif
 588
 589 /*
 590  * struct trace_parser - servers for reading the user input separated by spaces
 591  * @cont: set if the input is not complete - no final space char was found
 592  * @buffer: holds the parsed user input
 593  * @idx: user input length
 594  * @size: buffer size
 595  */
 596 struct trace_parser {
 597         bool            cont;
 598         char            *buffer;
 599         unsigned        idx;
 600         unsigned        size;
 601 };
 602
 603 static inline bool trace_parser_loaded(struct trace_parser *parser)
 604 {
 605         return (parser->idx != 0);
 606 }
 607
 608 static inline bool trace_parser_cont(struct trace_parser *parser)
 609 {
 610         return parser->cont;
 611 }
 612
 613 static inline void trace_parser_clear(struct trace_parser *parser)
 614 {
 615         parser->cont = false;
 616         parser->idx = 0;
 617 }
 618
 619 extern int trace_parser_get_init(struct trace_parser *parser, int size);
 620 extern void trace_parser_put(struct trace_parser *parser);
 621 extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
 622         size_t cnt, loff_t *ppos);
 623
 624 /*
 625  * trace_iterator_flags is an enumeration that defines bit
 626  * positions into trace_flags that controls the output.
 627  *
 628  * NOTE: These bits must match the trace_options array in
 629  *       trace.c.
 630  */
 631 enum trace_iterator_flags {
 632         TRACE_ITER_PRINT_PARENT         = 0x01,
 633         TRACE_ITER_SYM_OFFSET           = 0x02,
 634         TRACE_ITER_SYM_ADDR             = 0x04,
 635         TRACE_ITER_VERBOSE              = 0x08,
 636         TRACE_ITER_RAW                  = 0x10,
 637         TRACE_ITER_HEX                  = 0x20,
 638         TRACE_ITER_BIN                  = 0x40,
 639         TRACE_ITER_BLOCK                = 0x80,
 640         TRACE_ITER_STACKTRACE           = 0x100,
 641         TRACE_ITER_PRINTK               = 0x200,
 642         TRACE_ITER_PREEMPTONLY          = 0x400,
 643         TRACE_ITER_BRANCH               = 0x800,
 644         TRACE_ITER_ANNOTATE             = 0x1000,
 645         TRACE_ITER_USERSTACKTRACE       = 0x2000,
 646         TRACE_ITER_SYM_USEROBJ          = 0x4000,
 647         TRACE_ITER_PRINTK_MSGONLY       = 0x8000,
 648         TRACE_ITER_CONTEXT_INFO         = 0x10000, /* Print pid/cpu/time */
 649         TRACE_ITER_LATENCY_FMT          = 0x20000,
 650         TRACE_ITER_SLEEP_TIME           = 0x40000,
 651         TRACE_ITER_GRAPH_TIME           = 0x80000,
 652         TRACE_ITER_RECORD_CMD           = 0x100000,
 653         TRACE_ITER_OVERWRITE            = 0x200000,
 654         TRACE_ITER_STOP_ON_FREE         = 0x400000,
 655 };
 656
 657 /*
 658  * TRACE_ITER_SYM_MASK masks the options in trace_flags that
 659  * control the output of kernel symbols.
 660  */
 661 #define TRACE_ITER_SYM_MASK \
 662         (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
 663
 664 extern struct tracer nop_trace;
 665
 666 #ifdef CONFIG_BRANCH_TRACER
 667 extern int enable_branch_tracing(struct trace_array *tr);
 668 extern void disable_branch_tracing(void);
 669 static inline int trace_branch_enable(struct trace_array *tr)
 670 {
 671         if (trace_flags & TRACE_ITER_BRANCH)
 672                 return enable_branch_tracing(tr);
 673         return 0;
 674 }
 675 static inline void trace_branch_disable(void)
 676 {
 677         /* due to races, always disable */
 678         disable_branch_tracing();
 679 }
 680 #else
 681 static inline int trace_branch_enable(struct trace_array *tr)
 682 {
 683         return 0;
 684 }
 685 static inline void trace_branch_disable(void)
 686 {
 687 }
 688 #endif /* CONFIG_BRANCH_TRACER */
 689
 690 /* set ring buffers to default size if not already done so */
 691 int tracing_update_buffers(void);
 692
 693 /* trace event type bit fields, not numeric */
 694 enum {
 695         TRACE_EVENT_TYPE_PRINTF         = 1,
 696         TRACE_EVENT_TYPE_RAW            = 2,
 697 };
 698
 699 struct ftrace_event_field {
 700         struct list_head        link;
 701         char                    *name;
 702         char                    *type;
 703         int                     filter_type;
 704         int                     offset;
 705         int                     size;
 706         int                     is_signed;
 707 };
 708
 709 struct event_filter {
 710         int                     n_preds;        /* Number assigned */
 711         int                     a_preds;        /* allocated */
 712         struct filter_pred      *preds;
 713         struct filter_pred      *root;
 714         char                    *filter_string;
 715 };
 716
 717 struct event_subsystem {
 718         struct list_head        list;
 719         const char              *name;
 720         struct dentry           *entry;
 721         struct event_filter     *filter;
 722         int                     nr_events;
 723         int                     ref_count;
 724 };
 725
 726 #define FILTER_PRED_INVALID     ((unsigned short)-1)
 727 #define FILTER_PRED_IS_RIGHT    (1 << 15)
 728 #define FILTER_PRED_FOLD        (1 << 15)
 729
 730 /*
 731  * The max preds is the size of unsigned short with
 732  * two flags at the MSBs. One bit is used for both the IS_RIGHT
 733  * and FOLD flags. The other is reserved.
 734  *
 735  * 2^14 preds is way more than enough.
 736  */
 737 #define MAX_FILTER_PRED         16384
 738
 739 struct filter_pred;
 740 struct regex;
 741
 742 typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event);
 743
 744 typedef int (*regex_match_func)(char *str, struct regex *r, int len);
 745
 746 enum regex_type {
 747         MATCH_FULL = 0,
 748         MATCH_FRONT_ONLY,
 749         MATCH_MIDDLE_ONLY,
 750         MATCH_END_ONLY,
 751 };
 752
 753 struct regex {
 754         char                    pattern[MAX_FILTER_STR_VAL];
 755         int                     len;
 756         int                     field_len;
 757         regex_match_func        match;
 758 };
 759
 760 struct filter_pred {
 761         filter_pred_fn_t        fn;
 762         u64                     val;
 763         struct regex            regex;
 764         /*
 765          * Leaf nodes use field_name, ops is used by AND and OR
 766          * nodes. The field_name is always freed when freeing a pred.
 767          * We can overload field_name for ops and have it freed
 768          * as well.
 769          */
 770         union {
 771                 char            *field_name;
 772                 unsigned short  *ops;
 773         };
 774         int                     offset;
 775         int                     not;
 776         int                     op;
 777         unsigned short          index;
 778         unsigned short          parent;
 779         unsigned short          left;
 780         unsigned short          right;
 781 };
 782
 783 extern struct list_head ftrace_common_fields;
 784
 785 extern enum regex_type
 786 filter_parse_regex(char *buff, int len, char **search, int *not);
 787 extern void print_event_filter(struct ftrace_event_call *call,
 788                                struct trace_seq *s);
 789 extern int apply_event_filter(struct ftrace_event_call *call,
 790                               char *filter_string);
 791 extern int apply_subsystem_event_filter(struct event_subsystem *system,
 792                                         char *filter_string);
 793 extern void print_subsystem_event_filter(struct event_subsystem *system,
 794                                          struct trace_seq *s);
 795 extern int filter_assign_type(const char *type);
 796
 797 struct list_head *
 798 trace_get_fields(struct ftrace_event_call *event_call);
 799
 800 static inline int
 801 filter_check_discard(struct ftrace_event_call *call, void *rec,
 802                      struct ring_buffer *buffer,
 803                      struct ring_buffer_event *event)
 804 {
 805         if (unlikely(call->flags & TRACE_EVENT_FL_FILTERED) &&
 806             !filter_match_preds(call->filter, rec)) {
 807                 ring_buffer_discard_commit(buffer, event);
 808                 return 1;
 809         }
 810
 811         return 0;
 812 }
 813
 814 extern void trace_event_enable_cmd_record(bool enable);
 815
 816 extern struct mutex event_mutex;
 817 extern struct list_head ftrace_events;
 818
 819 extern const char *__start___trace_bprintk_fmt[];
 820 extern const char *__stop___trace_bprintk_fmt[];
 821
 822 #undef FTRACE_ENTRY
 823 #define FTRACE_ENTRY(call, struct_name, id, tstruct, print)             \
 824         extern struct ftrace_event_call                                 \
 825         __attribute__((__aligned__(4))) event_##call;
 826 #undef FTRACE_ENTRY_DUP
 827 #define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print)         \
 828         FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
 829 #include "trace_entries.h"
 830
 831 #endif /* _LINUX_KERNEL_TRACE_H */