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 #ifdef CONFIG_FTRACE_SYSCALLS
  17 #include <asm/unistd.h>         /* For NR_SYSCALLS           */
  18 #include <asm/syscall.h>        /* some archs define it here */
  19 #endif
  20
  21 enum trace_type {
  22         __TRACE_FIRST_TYPE = 0,
  23
  24         TRACE_FN,
  25         TRACE_CTX,
  26         TRACE_WAKE,
  27         TRACE_STACK,
  28         TRACE_PRINT,
  29         TRACE_BPRINT,
  30         TRACE_MMIO_RW,
  31         TRACE_MMIO_MAP,
  32         TRACE_BRANCH,
  33         TRACE_GRAPH_RET,
  34         TRACE_GRAPH_ENT,
  35         TRACE_USER_STACK,
  36         TRACE_BLK,
  37         TRACE_BPUTS,
  38
  39         __TRACE_LAST_TYPE,
  40 };
  41
  42
  43 #undef __field
  44 #define __field(type, item)             type    item;
  45
  46 #undef __field_struct
  47 #define __field_struct(type, item)      __field(type, item)
  48
  49 #undef __field_desc
  50 #define __field_desc(type, container, item)
  51
  52 #undef __array
  53 #define __array(type, item, size)       type    item[size];
  54
  55 #undef __array_desc
  56 #define __array_desc(type, container, item, size)
  57
  58 #undef __dynamic_array
  59 #define __dynamic_array(type, item)     type    item[];
  60
  61 #undef F_STRUCT
  62 #define F_STRUCT(args...)               args
  63
  64 #undef FTRACE_ENTRY
  65 #define FTRACE_ENTRY(name, struct_name, id, tstruct, print, filter)     \
  66         struct struct_name {                                            \
  67                 struct trace_entry      ent;                            \
  68                 tstruct                                                 \
  69         }
  70
  71 #undef TP_ARGS
  72 #define TP_ARGS(args...)        args
  73
  74 #undef FTRACE_ENTRY_DUP
  75 #define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk, filter)
  76
  77 #undef FTRACE_ENTRY_REG
  78 #define FTRACE_ENTRY_REG(name, struct_name, id, tstruct, print, \
  79                          filter, regfn) \
  80         FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print), \
  81                      filter)
  82
  83 #include "trace_entries.h"
  84
  85 /*
  86  * syscalls are special, and need special handling, this is why
  87  * they are not included in trace_entries.h
  88  */
  89 struct syscall_trace_enter {
  90         struct trace_entry      ent;
  91         int                     nr;
  92         unsigned long           args[];
  93 };
  94
  95 struct syscall_trace_exit {
  96         struct trace_entry      ent;
  97         int                     nr;
  98         long                    ret;
  99 };
 100
 101 struct kprobe_trace_entry_head {
 102         struct trace_entry      ent;
 103         unsigned long           ip;
 104 };
 105
 106 struct kretprobe_trace_entry_head {
 107         struct trace_entry      ent;
 108         unsigned long           func;
 109         unsigned long           ret_ip;
 110 };
 111
 112 /*
 113  * trace_flag_type is an enumeration that holds different
 114  * states when a trace occurs. These are:
 115  *  IRQS_OFF            - interrupts were disabled
 116  *  IRQS_NOSUPPORT      - arch does not support irqs_disabled_flags
 117  *  NEED_RESCHED        - reschedule is requested
 118  *  HARDIRQ             - inside an interrupt handler
 119  *  SOFTIRQ             - inside a softirq handler
 120  */
 121 enum trace_flag_type {
 122         TRACE_FLAG_IRQS_OFF             = 0x01,
 123         TRACE_FLAG_IRQS_NOSUPPORT       = 0x02,
 124         TRACE_FLAG_NEED_RESCHED         = 0x04,
 125         TRACE_FLAG_HARDIRQ              = 0x08,
 126         TRACE_FLAG_SOFTIRQ              = 0x10,
 127 };
 128
 129 #define TRACE_BUF_SIZE          1024
 130
 131 struct trace_array;
 132
 133 struct trace_cpu {
 134         struct trace_array      *tr;
 135         struct dentry           *dir;
 136         int                     cpu;
 137 };
 138
 139 /*
 140  * The CPU trace array - it consists of thousands of trace entries
 141  * plus some other descriptor data: (for example which task started
 142  * the trace, etc.)
 143  */
 144 struct trace_array_cpu {
 145         struct trace_cpu        trace_cpu;
 146         atomic_t                disabled;
 147         void                    *buffer_page;   /* ring buffer spare */
 148
 149         unsigned long           entries;
 150         unsigned long           saved_latency;
 151         unsigned long           critical_start;
 152         unsigned long           critical_end;
 153         unsigned long           critical_sequence;
 154         unsigned long           nice;
 155         unsigned long           policy;
 156         unsigned long           rt_priority;
 157         unsigned long           skipped_entries;
 158         cycle_t                 preempt_timestamp;
 159         pid_t                   pid;
 160         kuid_t                  uid;
 161         char                    comm[TASK_COMM_LEN];
 162 };
 163
 164 struct tracer;
 165
 166 struct trace_buffer {
 167         struct trace_array              *tr;
 168         struct ring_buffer              *buffer;
 169         struct trace_array_cpu __percpu *data;
 170         cycle_t                         time_start;
 171         int                             cpu;
 172 };
 173
 174 /*
 175  * The trace array - an array of per-CPU trace arrays. This is the
 176  * highest level data structure that individual tracers deal with.
 177  * They have on/off state as well:
 178  */
 179 struct trace_array {
 180         struct list_head        list;
 181         char                    *name;
 182         struct trace_buffer     trace_buffer;
 183 #ifdef CONFIG_TRACER_MAX_TRACE
 184         /*
 185          * The max_buffer is used to snapshot the trace when a maximum
 186          * latency is reached, or when the user initiates a snapshot.
 187          * Some tracers will use this to store a maximum trace while
 188          * it continues examining live traces.
 189          *
 190          * The buffers for the max_buffer are set up the same as the trace_buffer
 191          * When a snapshot is taken, the buffer of the max_buffer is swapped
 192          * with the buffer of the trace_buffer and the buffers are reset for
 193          * the trace_buffer so the tracing can continue.
 194          */
 195         struct trace_buffer     max_buffer;
 196         bool                    allocated_snapshot;
 197 #endif
 198         int                     buffer_disabled;
 199         struct trace_cpu        trace_cpu;      /* place holder */
 200 #ifdef CONFIG_FTRACE_SYSCALLS
 201         int                     sys_refcount_enter;
 202         int                     sys_refcount_exit;
 203         DECLARE_BITMAP(enabled_enter_syscalls, NR_syscalls);
 204         DECLARE_BITMAP(enabled_exit_syscalls, NR_syscalls);
 205 #endif
 206         int                     stop_count;
 207         int                     clock_id;
 208         struct tracer           *current_trace;
 209         unsigned int            flags;
 210         raw_spinlock_t          start_lock;
 211         struct dentry           *dir;
 212         struct dentry           *options;
 213         struct dentry           *percpu_dir;
 214         struct dentry           *event_dir;
 215         struct list_head        systems;
 216         struct list_head        events;
 217         struct task_struct      *waiter;
 218         int                     ref;
 219 };
 220
 221 enum {
 222         TRACE_ARRAY_FL_GLOBAL   = (1 << 0)
 223 };
 224
 225 extern struct list_head ftrace_trace_arrays;
 226
 227 extern struct mutex trace_types_lock;
 228
 229 extern int trace_array_get(struct trace_array *tr);
 230 extern void trace_array_put(struct trace_array *tr);
 231
 232 /*
 233  * The global tracer (top) should be the first trace array added,
 234  * but we check the flag anyway.
 235  */
 236 static inline struct trace_array *top_trace_array(void)
 237 {
 238         struct trace_array *tr;
 239
 240         tr = list_entry(ftrace_trace_arrays.prev,
 241                         typeof(*tr), list);
 242         WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL));
 243         return tr;
 244 }
 245
 246 #define FTRACE_CMP_TYPE(var, type) \
 247         __builtin_types_compatible_p(typeof(var), type *)
 248
 249 #undef IF_ASSIGN
 250 #define IF_ASSIGN(var, entry, etype, id)                \
 251         if (FTRACE_CMP_TYPE(var, etype)) {              \
 252                 var = (typeof(var))(entry);             \
 253                 WARN_ON(id && (entry)->type != id);     \
 254                 break;                                  \
 255         }
 256
 257 /* Will cause compile errors if type is not found. */
 258 extern void __ftrace_bad_type(void);
 259
 260 /*
 261  * The trace_assign_type is a verifier that the entry type is
 262  * the same as the type being assigned. To add new types simply
 263  * add a line with the following format:
 264  *
 265  * IF_ASSIGN(var, ent, type, id);
 266  *
 267  *  Where "type" is the trace type that includes the trace_entry
 268  *  as the "ent" item. And "id" is the trace identifier that is
 269  *  used in the trace_type enum.
 270  *
 271  *  If the type can have more than one id, then use zero.
 272  */
 273 #define trace_assign_type(var, ent)                                     \
 274         do {                                                            \
 275                 IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN);     \
 276                 IF_ASSIGN(var, ent, struct ctx_switch_entry, 0);        \
 277                 IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK);   \
 278                 IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
 279                 IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT);   \
 280                 IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT); \
 281                 IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS);   \
 282                 IF_ASSIGN(var, ent, struct trace_mmiotrace_rw,          \
 283                           TRACE_MMIO_RW);                               \
 284                 IF_ASSIGN(var, ent, struct trace_mmiotrace_map,         \
 285                           TRACE_MMIO_MAP);                              \
 286                 IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
 287                 IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry,      \
 288                           TRACE_GRAPH_ENT);             \
 289                 IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry,      \
 290                           TRACE_GRAPH_RET);             \
 291                 __ftrace_bad_type();                                    \
 292         } while (0)
 293
 294 /*
 295  * An option specific to a tracer. This is a boolean value.
 296  * The bit is the bit index that sets its value on the
 297  * flags value in struct tracer_flags.
 298  */
 299 struct tracer_opt {
 300         const char      *name; /* Will appear on the trace_options file */
 301         u32             bit; /* Mask assigned in val field in tracer_flags */
 302 };
 303
 304 /*
 305  * The set of specific options for a tracer. Your tracer
 306  * have to set the initial value of the flags val.
 307  */
 308 struct tracer_flags {
 309         u32                     val;
 310         struct tracer_opt       *opts;
 311 };
 312
 313 /* Makes more easy to define a tracer opt */
 314 #define TRACER_OPT(s, b)        .name = #s, .bit = b
 315
 316
 317 /**
 318  * struct tracer - a specific tracer and its callbacks to interact with debugfs
 319  * @name: the name chosen to select it on the available_tracers file
 320  * @init: called when one switches to this tracer (echo name > current_tracer)
 321  * @reset: called when one switches to another tracer
 322  * @start: called when tracing is unpaused (echo 1 > tracing_enabled)
 323  * @stop: called when tracing is paused (echo 0 > tracing_enabled)
 324  * @open: called when the trace file is opened
 325  * @pipe_open: called when the trace_pipe file is opened
 326  * @wait_pipe: override how the user waits for traces on trace_pipe
 327  * @close: called when the trace file is released
 328  * @pipe_close: called when the trace_pipe file is released
 329  * @read: override the default read callback on trace_pipe
 330  * @splice_read: override the default splice_read callback on trace_pipe
 331  * @selftest: selftest to run on boot (see trace_selftest.c)
 332  * @print_headers: override the first lines that describe your columns
 333  * @print_line: callback that prints a trace
 334  * @set_flag: signals one of your private flags changed (trace_options file)
 335  * @flags: your private flags
 336  */
 337 struct tracer {
 338         const char              *name;
 339         int                     (*init)(struct trace_array *tr);
 340         void                    (*reset)(struct trace_array *tr);
 341         void                    (*start)(struct trace_array *tr);
 342         void                    (*stop)(struct trace_array *tr);
 343         void                    (*open)(struct trace_iterator *iter);
 344         void                    (*pipe_open)(struct trace_iterator *iter);
 345         int                     (*wait_pipe)(struct trace_iterator *iter);
 346         void                    (*close)(struct trace_iterator *iter);
 347         void                    (*pipe_close)(struct trace_iterator *iter);
 348         ssize_t                 (*read)(struct trace_iterator *iter,
 349                                         struct file *filp, char __user *ubuf,
 350                                         size_t cnt, loff_t *ppos);
 351         ssize_t                 (*splice_read)(struct trace_iterator *iter,
 352                                                struct file *filp,
 353                                                loff_t *ppos,
 354                                                struct pipe_inode_info *pipe,
 355                                                size_t len,
 356                                                unsigned int flags);
 357 #ifdef CONFIG_FTRACE_STARTUP_TEST
 358         int                     (*selftest)(struct tracer *trace,
 359                                             struct trace_array *tr);
 360 #endif
 361         void                    (*print_header)(struct seq_file *m);
 362         enum print_line_t       (*print_line)(struct trace_iterator *iter);
 363         /* If you handled the flag setting, return 0 */
 364         int                     (*set_flag)(u32 old_flags, u32 bit, int set);
 365         /* Return 0 if OK with change, else return non-zero */
 366         int                     (*flag_changed)(struct tracer *tracer,
 367                                                 u32 mask, int set);
 368         struct tracer           *next;
 369         struct tracer_flags     *flags;
 370         bool                    print_max;
 371         bool                    enabled;
 372 #ifdef CONFIG_TRACER_MAX_TRACE
 373         bool                    use_max_tr;
 374 #endif
 375 };
 376
 377
 378 /* Only current can touch trace_recursion */
 379
 380 /*
 381  * For function tracing recursion:
 382  *  The order of these bits are important.
 383  *
 384  *  When function tracing occurs, the following steps are made:
 385  *   If arch does not support a ftrace feature:
 386  *    call internal function (uses INTERNAL bits) which calls...
 387  *   If callback is registered to the "global" list, the list
 388  *    function is called and recursion checks the GLOBAL bits.
 389  *    then this function calls...
 390  *   The function callback, which can use the FTRACE bits to
 391  *    check for recursion.
 392  *
 393  * Now if the arch does not suppport a feature, and it calls
 394  * the global list function which calls the ftrace callback
 395  * all three of these steps will do a recursion protection.
 396  * There's no reason to do one if the previous caller already
 397  * did. The recursion that we are protecting against will
 398  * go through the same steps again.
 399  *
 400  * To prevent the multiple recursion checks, if a recursion
 401  * bit is set that is higher than the MAX bit of the current
 402  * check, then we know that the check was made by the previous
 403  * caller, and we can skip the current check.
 404  */
 405 enum {
 406         TRACE_BUFFER_BIT,
 407         TRACE_BUFFER_NMI_BIT,
 408         TRACE_BUFFER_IRQ_BIT,
 409         TRACE_BUFFER_SIRQ_BIT,
 410
 411         /* Start of function recursion bits */
 412         TRACE_FTRACE_BIT,
 413         TRACE_FTRACE_NMI_BIT,
 414         TRACE_FTRACE_IRQ_BIT,
 415         TRACE_FTRACE_SIRQ_BIT,
 416
 417         /* GLOBAL_BITs must be greater than FTRACE_BITs */
 418         TRACE_GLOBAL_BIT,
 419         TRACE_GLOBAL_NMI_BIT,
 420         TRACE_GLOBAL_IRQ_BIT,
 421         TRACE_GLOBAL_SIRQ_BIT,
 422
 423         /* INTERNAL_BITs must be greater than GLOBAL_BITs */
 424         TRACE_INTERNAL_BIT,
 425         TRACE_INTERNAL_NMI_BIT,
 426         TRACE_INTERNAL_IRQ_BIT,
 427         TRACE_INTERNAL_SIRQ_BIT,
 428
 429         TRACE_CONTROL_BIT,
 430
 431         TRACE_BRANCH_BIT,
 432 /*
 433  * Abuse of the trace_recursion.
 434  * As we need a way to maintain state if we are tracing the function
 435  * graph in irq because we want to trace a particular function that
 436  * was called in irq context but we have irq tracing off. Since this
 437  * can only be modified by current, we can reuse trace_recursion.
 438  */
 439         TRACE_IRQ_BIT,
 440 };
 441
 442 #define trace_recursion_set(bit)        do { (current)->trace_recursion |= (1<<(bit)); } while (0)
 443 #define trace_recursion_clear(bit)      do { (current)->trace_recursion &= ~(1<<(bit)); } while (0)
 444 #define trace_recursion_test(bit)       ((current)->trace_recursion & (1<<(bit)))
 445
 446 #define TRACE_CONTEXT_BITS      4
 447
 448 #define TRACE_FTRACE_START      TRACE_FTRACE_BIT
 449 #define TRACE_FTRACE_MAX        ((1 << (TRACE_FTRACE_START + TRACE_CONTEXT_BITS)) - 1)
 450
 451 #define TRACE_GLOBAL_START      TRACE_GLOBAL_BIT
 452 #define TRACE_GLOBAL_MAX        ((1 << (TRACE_GLOBAL_START + TRACE_CONTEXT_BITS)) - 1)
 453
 454 #define TRACE_LIST_START        TRACE_INTERNAL_BIT
 455 #define TRACE_LIST_MAX          ((1 << (TRACE_LIST_START + TRACE_CONTEXT_BITS)) - 1)
 456
 457 #define TRACE_CONTEXT_MASK      TRACE_LIST_MAX
 458
 459 static __always_inline int trace_get_context_bit(void)
 460 {
 461         int bit;
 462
 463         if (in_interrupt()) {
 464                 if (in_nmi())
 465                         bit = 0;
 466
 467                 else if (in_irq())
 468                         bit = 1;
 469                 else
 470                         bit = 2;
 471         } else
 472                 bit = 3;
 473
 474         return bit;
 475 }
 476
 477 static __always_inline int trace_test_and_set_recursion(int start, int max)
 478 {
 479         unsigned int val = current->trace_recursion;
 480         int bit;
 481
 482         /* A previous recursion check was made */
 483         if ((val & TRACE_CONTEXT_MASK) > max)
 484                 return 0;
 485
 486         bit = trace_get_context_bit() + start;
 487         if (unlikely(val & (1 << bit)))
 488                 return -1;
 489
 490         val |= 1 << bit;
 491         current->trace_recursion = val;
 492         barrier();
 493
 494         return bit;
 495 }
 496
 497 static __always_inline void trace_clear_recursion(int bit)
 498 {
 499         unsigned int val = current->trace_recursion;
 500
 501         if (!bit)
 502                 return;
 503
 504         bit = 1 << bit;
 505         val &= ~bit;
 506
 507         barrier();
 508         current->trace_recursion = val;
 509 }
 510
 511 static inline struct ring_buffer_iter *
 512 trace_buffer_iter(struct trace_iterator *iter, int cpu)
 513 {
 514         if (iter->buffer_iter && iter->buffer_iter[cpu])
 515                 return iter->buffer_iter[cpu];
 516         return NULL;
 517 }
 518
 519 int tracer_init(struct tracer *t, struct trace_array *tr);
 520 int tracing_is_enabled(void);
 521 void tracing_reset(struct trace_buffer *buf, int cpu);
 522 void tracing_reset_online_cpus(struct trace_buffer *buf);
 523 void tracing_reset_current(int cpu);
 524 void tracing_reset_all_online_cpus(void);
 525 int tracing_open_generic(struct inode *inode, struct file *filp);
 526 struct dentry *trace_create_file(const char *name,
 527                                  umode_t mode,
 528                                  struct dentry *parent,
 529                                  void *data,
 530                                  const struct file_operations *fops);
 531
 532 struct dentry *tracing_init_dentry_tr(struct trace_array *tr);
 533 struct dentry *tracing_init_dentry(void);
 534
 535 struct ring_buffer_event;
 536
 537 struct ring_buffer_event *
 538 trace_buffer_lock_reserve(struct ring_buffer *buffer,
 539                           int type,
 540                           unsigned long len,
 541                           unsigned long flags,
 542                           int pc);
 543
 544 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
 545                                                 struct trace_array_cpu *data);
 546
 547 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
 548                                           int *ent_cpu, u64 *ent_ts);
 549
 550 void __buffer_unlock_commit(struct ring_buffer *buffer,
 551                             struct ring_buffer_event *event);
 552
 553 int trace_empty(struct trace_iterator *iter);
 554
 555 void *trace_find_next_entry_inc(struct trace_iterator *iter);
 556
 557 void trace_init_global_iter(struct trace_iterator *iter);
 558
 559 void tracing_iter_reset(struct trace_iterator *iter, int cpu);
 560
 561 int poll_wait_pipe(struct trace_iterator *iter);
 562
 563 void ftrace(struct trace_array *tr,
 564                             struct trace_array_cpu *data,
 565                             unsigned long ip,
 566                             unsigned long parent_ip,
 567                             unsigned long flags, int pc);
 568 void tracing_sched_switch_trace(struct trace_array *tr,
 569                                 struct task_struct *prev,
 570                                 struct task_struct *next,
 571                                 unsigned long flags, int pc);
 572
 573 void tracing_sched_wakeup_trace(struct trace_array *tr,
 574                                 struct task_struct *wakee,
 575                                 struct task_struct *cur,
 576                                 unsigned long flags, int pc);
 577 void trace_function(struct trace_array *tr,
 578                     unsigned long ip,
 579                     unsigned long parent_ip,
 580                     unsigned long flags, int pc);
 581 void trace_graph_function(struct trace_array *tr,
 582                     unsigned long ip,
 583                     unsigned long parent_ip,
 584                     unsigned long flags, int pc);
 585 void trace_latency_header(struct seq_file *m);
 586 void trace_default_header(struct seq_file *m);
 587 void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
 588 int trace_empty(struct trace_iterator *iter);
 589
 590 void trace_graph_return(struct ftrace_graph_ret *trace);
 591 int trace_graph_entry(struct ftrace_graph_ent *trace);
 592 void set_graph_array(struct trace_array *tr);
 593
 594 void tracing_start_cmdline_record(void);
 595 void tracing_stop_cmdline_record(void);
 596 void tracing_sched_switch_assign_trace(struct trace_array *tr);
 597 void tracing_stop_sched_switch_record(void);
 598 void tracing_start_sched_switch_record(void);
 599 int register_tracer(struct tracer *type);
 600 int is_tracing_stopped(void);
 601
 602 extern cpumask_var_t __read_mostly tracing_buffer_mask;
 603
 604 #define for_each_tracing_cpu(cpu)       \
 605         for_each_cpu(cpu, tracing_buffer_mask)
 606
 607 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
 608
 609 extern unsigned long tracing_thresh;
 610
 611 #ifdef CONFIG_TRACER_MAX_TRACE
 612 extern unsigned long tracing_max_latency;
 613
 614 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu);
 615 void update_max_tr_single(struct trace_array *tr,
 616                           struct task_struct *tsk, int cpu);
 617 #endif /* CONFIG_TRACER_MAX_TRACE */
 618
 619 #ifdef CONFIG_STACKTRACE
 620 void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags,
 621                         int skip, int pc);
 622
 623 void ftrace_trace_stack_regs(struct ring_buffer *buffer, unsigned long flags,
 624                              int skip, int pc, struct pt_regs *regs);
 625
 626 void ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags,
 627                             int pc);
 628
 629 void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
 630                    int pc);
 631 #else
 632 static inline void ftrace_trace_stack(struct ring_buffer *buffer,
 633                                       unsigned long flags, int skip, int pc)
 634 {
 635 }
 636
 637 static inline void ftrace_trace_stack_regs(struct ring_buffer *buffer,
 638                                            unsigned long flags, int skip,
 639                                            int pc, struct pt_regs *regs)
 640 {
 641 }
 642
 643 static inline void ftrace_trace_userstack(struct ring_buffer *buffer,
 644                                           unsigned long flags, int pc)
 645 {
 646 }
 647
 648 static inline void __trace_stack(struct trace_array *tr, unsigned long flags,
 649                                  int skip, int pc)
 650 {
 651 }
 652 #endif /* CONFIG_STACKTRACE */
 653
 654 extern cycle_t ftrace_now(int cpu);
 655
 656 extern void trace_find_cmdline(int pid, char comm[]);
 657
 658 #ifdef CONFIG_DYNAMIC_FTRACE
 659 extern unsigned long ftrace_update_tot_cnt;
 660 #endif
 661 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
 662 extern int DYN_FTRACE_TEST_NAME(void);
 663 #define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
 664 extern int DYN_FTRACE_TEST_NAME2(void);
 665
 666 extern bool ring_buffer_expanded;
 667 extern bool tracing_selftest_disabled;
 668 DECLARE_PER_CPU(int, ftrace_cpu_disabled);
 669
 670 #ifdef CONFIG_FTRACE_STARTUP_TEST
 671 extern int trace_selftest_startup_function(struct tracer *trace,
 672                                            struct trace_array *tr);
 673 extern int trace_selftest_startup_function_graph(struct tracer *trace,
 674                                                  struct trace_array *tr);
 675 extern int trace_selftest_startup_irqsoff(struct tracer *trace,
 676                                           struct trace_array *tr);
 677 extern int trace_selftest_startup_preemptoff(struct tracer *trace,
 678                                              struct trace_array *tr);
 679 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
 680                                                  struct trace_array *tr);
 681 extern int trace_selftest_startup_wakeup(struct tracer *trace,
 682                                          struct trace_array *tr);
 683 extern int trace_selftest_startup_nop(struct tracer *trace,
 684                                          struct trace_array *tr);
 685 extern int trace_selftest_startup_sched_switch(struct tracer *trace,
 686                                                struct trace_array *tr);
 687 extern int trace_selftest_startup_branch(struct tracer *trace,
 688                                          struct trace_array *tr);
 689 #endif /* CONFIG_FTRACE_STARTUP_TEST */
 690
 691 extern void *head_page(struct trace_array_cpu *data);
 692 extern unsigned long long ns2usecs(cycle_t nsec);
 693 extern int
 694 trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
 695 extern int
 696 trace_vprintk(unsigned long ip, const char *fmt, va_list args);
 697 extern int
 698 trace_array_vprintk(struct trace_array *tr,
 699                     unsigned long ip, const char *fmt, va_list args);
 700 int trace_array_printk(struct trace_array *tr,
 701                        unsigned long ip, const char *fmt, ...);
 702 int trace_array_printk_buf(struct ring_buffer *buffer,
 703                            unsigned long ip, const char *fmt, ...);
 704 void trace_printk_seq(struct trace_seq *s);
 705 enum print_line_t print_trace_line(struct trace_iterator *iter);
 706
 707 extern unsigned long trace_flags;
 708
 709 /* Standard output formatting function used for function return traces */
 710 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
 711
 712 /* Flag options */
 713 #define TRACE_GRAPH_PRINT_OVERRUN       0x1
 714 #define TRACE_GRAPH_PRINT_CPU           0x2
 715 #define TRACE_GRAPH_PRINT_OVERHEAD      0x4
 716 #define TRACE_GRAPH_PRINT_PROC          0x8
 717 #define TRACE_GRAPH_PRINT_DURATION      0x10
 718 #define TRACE_GRAPH_PRINT_ABS_TIME      0x20
 719
 720 extern enum print_line_t
 721 print_graph_function_flags(struct trace_iterator *iter, u32 flags);
 722 extern void print_graph_headers_flags(struct seq_file *s, u32 flags);
 723 extern enum print_line_t
 724 trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
 725 extern void graph_trace_open(struct trace_iterator *iter);
 726 extern void graph_trace_close(struct trace_iterator *iter);
 727 extern int __trace_graph_entry(struct trace_array *tr,
 728                                struct ftrace_graph_ent *trace,
 729                                unsigned long flags, int pc);
 730 extern void __trace_graph_return(struct trace_array *tr,
 731                                  struct ftrace_graph_ret *trace,
 732                                  unsigned long flags, int pc);
 733
 734
 735 #ifdef CONFIG_DYNAMIC_FTRACE
 736 /* TODO: make this variable */
 737 #define FTRACE_GRAPH_MAX_FUNCS          32
 738 extern int ftrace_graph_filter_enabled;
 739 extern int ftrace_graph_count;
 740 extern unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS];
 741
 742 static inline int ftrace_graph_addr(unsigned long addr)
 743 {
 744         int i;
 745
 746         if (!ftrace_graph_filter_enabled)
 747                 return 1;
 748
 749         for (i = 0; i < ftrace_graph_count; i++) {
 750                 if (addr == ftrace_graph_funcs[i]) {
 751                         /*
 752                          * If no irqs are to be traced, but a set_graph_function
 753                          * is set, and called by an interrupt handler, we still
 754                          * want to trace it.
 755                          */
 756                         if (in_irq())
 757                                 trace_recursion_set(TRACE_IRQ_BIT);
 758                         else
 759                                 trace_recursion_clear(TRACE_IRQ_BIT);
 760                         return 1;
 761                 }
 762         }
 763
 764         return 0;
 765 }
 766 #else
 767 static inline int ftrace_graph_addr(unsigned long addr)
 768 {
 769         return 1;
 770 }
 771 #endif /* CONFIG_DYNAMIC_FTRACE */
 772 #else /* CONFIG_FUNCTION_GRAPH_TRACER */
 773 static inline enum print_line_t
 774 print_graph_function_flags(struct trace_iterator *iter, u32 flags)
 775 {
 776         return TRACE_TYPE_UNHANDLED;
 777 }
 778 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
 779
 780 extern struct list_head ftrace_pids;
 781
 782 #ifdef CONFIG_FUNCTION_TRACER
 783 static inline int ftrace_trace_task(struct task_struct *task)
 784 {
 785         if (list_empty(&ftrace_pids))
 786                 return 1;
 787
 788         return test_tsk_trace_trace(task);
 789 }
 790 extern int ftrace_is_dead(void);
 791 #else
 792 static inline int ftrace_trace_task(struct task_struct *task)
 793 {
 794         return 1;
 795 }
 796 static inline int ftrace_is_dead(void) { return 0; }
 797 #endif
 798
 799 int ftrace_event_is_function(struct ftrace_event_call *call);
 800
 801 /*
 802  * struct trace_parser - servers for reading the user input separated by spaces
 803  * @cont: set if the input is not complete - no final space char was found
 804  * @buffer: holds the parsed user input
 805  * @idx: user input length
 806  * @size: buffer size
 807  */
 808 struct trace_parser {
 809         bool            cont;
 810         char            *buffer;
 811         unsigned        idx;
 812         unsigned        size;
 813 };
 814
 815 static inline bool trace_parser_loaded(struct trace_parser *parser)
 816 {
 817         return (parser->idx != 0);
 818 }
 819
 820 static inline bool trace_parser_cont(struct trace_parser *parser)
 821 {
 822         return parser->cont;
 823 }
 824
 825 static inline void trace_parser_clear(struct trace_parser *parser)
 826 {
 827         parser->cont = false;
 828         parser->idx = 0;
 829 }
 830
 831 extern int trace_parser_get_init(struct trace_parser *parser, int size);
 832 extern void trace_parser_put(struct trace_parser *parser);
 833 extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
 834         size_t cnt, loff_t *ppos);
 835
 836 /*
 837  * trace_iterator_flags is an enumeration that defines bit
 838  * positions into trace_flags that controls the output.
 839  *
 840  * NOTE: These bits must match the trace_options array in
 841  *       trace.c.
 842  */
 843 enum trace_iterator_flags {
 844         TRACE_ITER_PRINT_PARENT         = 0x01,
 845         TRACE_ITER_SYM_OFFSET           = 0x02,
 846         TRACE_ITER_SYM_ADDR             = 0x04,
 847         TRACE_ITER_VERBOSE              = 0x08,
 848         TRACE_ITER_RAW                  = 0x10,
 849         TRACE_ITER_HEX                  = 0x20,
 850         TRACE_ITER_BIN                  = 0x40,
 851         TRACE_ITER_BLOCK                = 0x80,
 852         TRACE_ITER_STACKTRACE           = 0x100,
 853         TRACE_ITER_PRINTK               = 0x200,
 854         TRACE_ITER_PREEMPTONLY          = 0x400,
 855         TRACE_ITER_BRANCH               = 0x800,
 856         TRACE_ITER_ANNOTATE             = 0x1000,
 857         TRACE_ITER_USERSTACKTRACE       = 0x2000,
 858         TRACE_ITER_SYM_USEROBJ          = 0x4000,
 859         TRACE_ITER_PRINTK_MSGONLY       = 0x8000,
 860         TRACE_ITER_CONTEXT_INFO         = 0x10000, /* Print pid/cpu/time */
 861         TRACE_ITER_LATENCY_FMT          = 0x20000,
 862         TRACE_ITER_SLEEP_TIME           = 0x40000,
 863         TRACE_ITER_GRAPH_TIME           = 0x80000,
 864         TRACE_ITER_RECORD_CMD           = 0x100000,
 865         TRACE_ITER_OVERWRITE            = 0x200000,
 866         TRACE_ITER_STOP_ON_FREE         = 0x400000,
 867         TRACE_ITER_IRQ_INFO             = 0x800000,
 868         TRACE_ITER_MARKERS              = 0x1000000,
 869         TRACE_ITER_FUNCTION             = 0x2000000,
 870 };
 871
 872 /*
 873  * TRACE_ITER_SYM_MASK masks the options in trace_flags that
 874  * control the output of kernel symbols.
 875  */
 876 #define TRACE_ITER_SYM_MASK \
 877         (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
 878
 879 extern struct tracer nop_trace;
 880
 881 #ifdef CONFIG_BRANCH_TRACER
 882 extern int enable_branch_tracing(struct trace_array *tr);
 883 extern void disable_branch_tracing(void);
 884 static inline int trace_branch_enable(struct trace_array *tr)
 885 {
 886         if (trace_flags & TRACE_ITER_BRANCH)
 887                 return enable_branch_tracing(tr);
 888         return 0;
 889 }
 890 static inline void trace_branch_disable(void)
 891 {
 892         /* due to races, always disable */
 893         disable_branch_tracing();
 894 }
 895 #else
 896 static inline int trace_branch_enable(struct trace_array *tr)
 897 {
 898         return 0;
 899 }
 900 static inline void trace_branch_disable(void)
 901 {
 902 }
 903 #endif /* CONFIG_BRANCH_TRACER */
 904
 905 /* set ring buffers to default size if not already done so */
 906 int tracing_update_buffers(void);
 907
 908 /* trace event type bit fields, not numeric */
 909 enum {
 910         TRACE_EVENT_TYPE_PRINTF         = 1,
 911         TRACE_EVENT_TYPE_RAW            = 2,
 912 };
 913
 914 struct ftrace_event_field {
 915         struct list_head        link;
 916         const char              *name;
 917         const char              *type;
 918         int                     filter_type;
 919         int                     offset;
 920         int                     size;
 921         int                     is_signed;
 922 };
 923
 924 struct event_filter {
 925         int                     n_preds;        /* Number assigned */
 926         int                     a_preds;        /* allocated */
 927         struct filter_pred      *preds;
 928         struct filter_pred      *root;
 929         char                    *filter_string;
 930 };
 931
 932 struct event_subsystem {
 933         struct list_head        list;
 934         const char              *name;
 935         struct event_filter     *filter;
 936         int                     ref_count;
 937 };
 938
 939 struct ftrace_subsystem_dir {
 940         struct list_head                list;
 941         struct event_subsystem          *subsystem;
 942         struct trace_array              *tr;
 943         struct dentry                   *entry;
 944         int                             ref_count;
 945         int                             nr_events;
 946 };
 947
 948 #define FILTER_PRED_INVALID     ((unsigned short)-1)
 949 #define FILTER_PRED_IS_RIGHT    (1 << 15)
 950 #define FILTER_PRED_FOLD        (1 << 15)
 951
 952 /*
 953  * The max preds is the size of unsigned short with
 954  * two flags at the MSBs. One bit is used for both the IS_RIGHT
 955  * and FOLD flags. The other is reserved.
 956  *
 957  * 2^14 preds is way more than enough.
 958  */
 959 #define MAX_FILTER_PRED         16384
 960
 961 struct filter_pred;
 962 struct regex;
 963
 964 typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event);
 965
 966 typedef int (*regex_match_func)(char *str, struct regex *r, int len);
 967
 968 enum regex_type {
 969         MATCH_FULL = 0,
 970         MATCH_FRONT_ONLY,
 971         MATCH_MIDDLE_ONLY,
 972         MATCH_END_ONLY,
 973 };
 974
 975 struct regex {
 976         char                    pattern[MAX_FILTER_STR_VAL];
 977         int                     len;
 978         int                     field_len;
 979         regex_match_func        match;
 980 };
 981
 982 struct filter_pred {
 983         filter_pred_fn_t        fn;
 984         u64                     val;
 985         struct regex            regex;
 986         unsigned short          *ops;
 987         struct ftrace_event_field *field;
 988         int                     offset;
 989         int                     not;
 990         int                     op;
 991         unsigned short          index;
 992         unsigned short          parent;
 993         unsigned short          left;
 994         unsigned short          right;
 995 };
 996
 997 extern enum regex_type
 998 filter_parse_regex(char *buff, int len, char **search, int *not);
 999 extern void print_event_filter(struct ftrace_event_call *call,
1000                                struct trace_seq *s);
1001 extern int apply_event_filter(struct ftrace_event_call *call,
1002                               char *filter_string);
1003 extern int apply_subsystem_event_filter(struct ftrace_subsystem_dir *dir,
1004                                         char *filter_string);
1005 extern void print_subsystem_event_filter(struct event_subsystem *system,
1006                                          struct trace_seq *s);
1007 extern int filter_assign_type(const char *type);
1008
1009 struct ftrace_event_field *
1010 trace_find_event_field(struct ftrace_event_call *call, char *name);
1011
1012 static inline int
1013 filter_check_discard(struct ftrace_event_call *call, void *rec,
1014                      struct ring_buffer *buffer,
1015                      struct ring_buffer_event *event)
1016 {
1017         if (unlikely(call->flags & TRACE_EVENT_FL_FILTERED) &&
1018             !filter_match_preds(call->filter, rec)) {
1019                 ring_buffer_discard_commit(buffer, event);
1020                 return 1;
1021         }
1022
1023         return 0;
1024 }
1025
1026 extern void trace_event_enable_cmd_record(bool enable);
1027 extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr);
1028 extern int event_trace_del_tracer(struct trace_array *tr);
1029
1030 extern struct mutex event_mutex;
1031 extern struct list_head ftrace_events;
1032
1033 extern const char *__start___trace_bprintk_fmt[];
1034 extern const char *__stop___trace_bprintk_fmt[];
1035
1036 void trace_printk_init_buffers(void);
1037 void trace_printk_start_comm(void);
1038 int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set);
1039 int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled);
1040
1041 /*
1042  * Normal trace_printk() and friends allocates special buffers
1043  * to do the manipulation, as well as saves the print formats
1044  * into sections to display. But the trace infrastructure wants
1045  * to use these without the added overhead at the price of being
1046  * a bit slower (used mainly for warnings, where we don't care
1047  * about performance). The internal_trace_puts() is for such
1048  * a purpose.
1049  */
1050 #define internal_trace_puts(str) __trace_puts(_THIS_IP_, str, strlen(str))
1051
1052 #undef FTRACE_ENTRY
1053 #define FTRACE_ENTRY(call, struct_name, id, tstruct, print, filter)     \
1054         extern struct ftrace_event_call                                 \
1055         __attribute__((__aligned__(4))) event_##call;
1056 #undef FTRACE_ENTRY_DUP
1057 #define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print, filter) \
1058         FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print), \
1059                      filter)
1060 #include "trace_entries.h"
1061
1062 #if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER)
1063 int perf_ftrace_event_register(struct ftrace_event_call *call,
1064                                enum trace_reg type, void *data);
1065 #else
1066 #define perf_ftrace_event_register NULL
1067 #endif
1068
1069 #endif /* _LINUX_KERNEL_TRACE_H */