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