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 /*
 228  * The global tracer (top) should be the first trace array added,
 229  * but we check the flag anyway.
 230  */
 231 static inline struct trace_array *top_trace_array(void)
 232 {
 233         struct trace_array *tr;
 234
 235         tr = list_entry(ftrace_trace_arrays.prev,
 236                         typeof(*tr), list);
 237         WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL));
 238         return tr;
 239 }
 240
 241 #define FTRACE_CMP_TYPE(var, type) \
 242         __builtin_types_compatible_p(typeof(var), type *)
 243
 244 #undef IF_ASSIGN
 245 #define IF_ASSIGN(var, entry, etype, id)                \
 246         if (FTRACE_CMP_TYPE(var, etype)) {              \
 247                 var = (typeof(var))(entry);             \
 248                 WARN_ON(id && (entry)->type != id);     \
 249                 break;                                  \
 250         }
 251
 252 /* Will cause compile errors if type is not found. */
 253 extern void __ftrace_bad_type(void);
 254
 255 /*
 256  * The trace_assign_type is a verifier that the entry type is
 257  * the same as the type being assigned. To add new types simply
 258  * add a line with the following format:
 259  *
 260  * IF_ASSIGN(var, ent, type, id);
 261  *
 262  *  Where "type" is the trace type that includes the trace_entry
 263  *  as the "ent" item. And "id" is the trace identifier that is
 264  *  used in the trace_type enum.
 265  *
 266  *  If the type can have more than one id, then use zero.
 267  */
 268 #define trace_assign_type(var, ent)                                     \
 269         do {                                                            \
 270                 IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN);     \
 271                 IF_ASSIGN(var, ent, struct ctx_switch_entry, 0);        \
 272                 IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK);   \
 273                 IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
 274                 IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT);   \
 275                 IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT); \
 276                 IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS);   \
 277                 IF_ASSIGN(var, ent, struct trace_mmiotrace_rw,          \
 278                           TRACE_MMIO_RW);                               \
 279                 IF_ASSIGN(var, ent, struct trace_mmiotrace_map,         \
 280                           TRACE_MMIO_MAP);                              \
 281                 IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
 282                 IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry,      \
 283                           TRACE_GRAPH_ENT);             \
 284                 IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry,      \
 285                           TRACE_GRAPH_RET);             \
 286                 __ftrace_bad_type();                                    \
 287         } while (0)
 288
 289 /*
 290  * An option specific to a tracer. This is a boolean value.
 291  * The bit is the bit index that sets its value on the
 292  * flags value in struct tracer_flags.
 293  */
 294 struct tracer_opt {
 295         const char      *name; /* Will appear on the trace_options file */
 296         u32             bit; /* Mask assigned in val field in tracer_flags */
 297 };
 298
 299 /*
 300  * The set of specific options for a tracer. Your tracer
 301  * have to set the initial value of the flags val.
 302  */
 303 struct tracer_flags {
 304         u32                     val;
 305         struct tracer_opt       *opts;
 306 };
 307
 308 /* Makes more easy to define a tracer opt */
 309 #define TRACER_OPT(s, b)        .name = #s, .bit = b
 310
 311
 312 /**
 313  * struct tracer - a specific tracer and its callbacks to interact with debugfs
 314  * @name: the name chosen to select it on the available_tracers file
 315  * @init: called when one switches to this tracer (echo name > current_tracer)
 316  * @reset: called when one switches to another tracer
 317  * @start: called when tracing is unpaused (echo 1 > tracing_enabled)
 318  * @stop: called when tracing is paused (echo 0 > tracing_enabled)
 319  * @open: called when the trace file is opened
 320  * @pipe_open: called when the trace_pipe file is opened
 321  * @wait_pipe: override how the user waits for traces on trace_pipe
 322  * @close: called when the trace file is released
 323  * @pipe_close: called when the trace_pipe file is released
 324  * @read: override the default read callback on trace_pipe
 325  * @splice_read: override the default splice_read callback on trace_pipe
 326  * @selftest: selftest to run on boot (see trace_selftest.c)
 327  * @print_headers: override the first lines that describe your columns
 328  * @print_line: callback that prints a trace
 329  * @set_flag: signals one of your private flags changed (trace_options file)
 330  * @flags: your private flags
 331  */
 332 struct tracer {
 333         const char              *name;
 334         int                     (*init)(struct trace_array *tr);
 335         void                    (*reset)(struct trace_array *tr);
 336         void                    (*start)(struct trace_array *tr);
 337         void                    (*stop)(struct trace_array *tr);
 338         void                    (*open)(struct trace_iterator *iter);
 339         void                    (*pipe_open)(struct trace_iterator *iter);
 340         void                    (*wait_pipe)(struct trace_iterator *iter);
 341         void                    (*close)(struct trace_iterator *iter);
 342         void                    (*pipe_close)(struct trace_iterator *iter);
 343         ssize_t                 (*read)(struct trace_iterator *iter,
 344                                         struct file *filp, char __user *ubuf,
 345                                         size_t cnt, loff_t *ppos);
 346         ssize_t                 (*splice_read)(struct trace_iterator *iter,
 347                                                struct file *filp,
 348                                                loff_t *ppos,
 349                                                struct pipe_inode_info *pipe,
 350                                                size_t len,
 351                                                unsigned int flags);
 352 #ifdef CONFIG_FTRACE_STARTUP_TEST
 353         int                     (*selftest)(struct tracer *trace,
 354                                             struct trace_array *tr);
 355 #endif
 356         void                    (*print_header)(struct seq_file *m);
 357         enum print_line_t       (*print_line)(struct trace_iterator *iter);
 358         /* If you handled the flag setting, return 0 */
 359         int                     (*set_flag)(u32 old_flags, u32 bit, int set);
 360         /* Return 0 if OK with change, else return non-zero */
 361         int                     (*flag_changed)(struct tracer *tracer,
 362                                                 u32 mask, int set);
 363         struct tracer           *next;
 364         struct tracer_flags     *flags;
 365         bool                    print_max;
 366         bool                    enabled;
 367 #ifdef CONFIG_TRACER_MAX_TRACE
 368         bool                    use_max_tr;
 369 #endif
 370 };
 371
 372
 373 /* Only current can touch trace_recursion */
 374
 375 /*
 376  * For function tracing recursion:
 377  *  The order of these bits are important.
 378  *
 379  *  When function tracing occurs, the following steps are made:
 380  *   If arch does not support a ftrace feature:
 381  *    call internal function (uses INTERNAL bits) which calls...
 382  *   If callback is registered to the "global" list, the list
 383  *    function is called and recursion checks the GLOBAL bits.
 384  *    then this function calls...
 385  *   The function callback, which can use the FTRACE bits to
 386  *    check for recursion.
 387  *
 388  * Now if the arch does not suppport a feature, and it calls
 389  * the global list function which calls the ftrace callback
 390  * all three of these steps will do a recursion protection.
 391  * There's no reason to do one if the previous caller already
 392  * did. The recursion that we are protecting against will
 393  * go through the same steps again.
 394  *
 395  * To prevent the multiple recursion checks, if a recursion
 396  * bit is set that is higher than the MAX bit of the current
 397  * check, then we know that the check was made by the previous
 398  * caller, and we can skip the current check.
 399  */
 400 enum {
 401         TRACE_BUFFER_BIT,
 402         TRACE_BUFFER_NMI_BIT,
 403         TRACE_BUFFER_IRQ_BIT,
 404         TRACE_BUFFER_SIRQ_BIT,
 405
 406         /* Start of function recursion bits */
 407         TRACE_FTRACE_BIT,
 408         TRACE_FTRACE_NMI_BIT,
 409         TRACE_FTRACE_IRQ_BIT,
 410         TRACE_FTRACE_SIRQ_BIT,
 411
 412         /* GLOBAL_BITs must be greater than FTRACE_BITs */
 413         TRACE_GLOBAL_BIT,
 414         TRACE_GLOBAL_NMI_BIT,
 415         TRACE_GLOBAL_IRQ_BIT,
 416         TRACE_GLOBAL_SIRQ_BIT,
 417
 418         /* INTERNAL_BITs must be greater than GLOBAL_BITs */
 419         TRACE_INTERNAL_BIT,
 420         TRACE_INTERNAL_NMI_BIT,
 421         TRACE_INTERNAL_IRQ_BIT,
 422         TRACE_INTERNAL_SIRQ_BIT,
 423
 424         TRACE_CONTROL_BIT,
 425
 426 /*
 427  * Abuse of the trace_recursion.
 428  * As we need a way to maintain state if we are tracing the function
 429  * graph in irq because we want to trace a particular function that
 430  * was called in irq context but we have irq tracing off. Since this
 431  * can only be modified by current, we can reuse trace_recursion.
 432  */
 433         TRACE_IRQ_BIT,
 434 };
 435
 436 #define trace_recursion_set(bit)        do { (current)->trace_recursion |= (1<<(bit)); } while (0)
 437 #define trace_recursion_clear(bit)      do { (current)->trace_recursion &= ~(1<<(bit)); } while (0)
 438 #define trace_recursion_test(bit)       ((current)->trace_recursion & (1<<(bit)))
 439
 440 #define TRACE_CONTEXT_BITS      4
 441
 442 #define TRACE_FTRACE_START      TRACE_FTRACE_BIT
 443 #define TRACE_FTRACE_MAX        ((1 << (TRACE_FTRACE_START + TRACE_CONTEXT_BITS)) - 1)
 444
 445 #define TRACE_GLOBAL_START      TRACE_GLOBAL_BIT
 446 #define TRACE_GLOBAL_MAX        ((1 << (TRACE_GLOBAL_START + TRACE_CONTEXT_BITS)) - 1)
 447
 448 #define TRACE_LIST_START        TRACE_INTERNAL_BIT
 449 #define TRACE_LIST_MAX          ((1 << (TRACE_LIST_START + TRACE_CONTEXT_BITS)) - 1)
 450
 451 #define TRACE_CONTEXT_MASK      TRACE_LIST_MAX
 452
 453 static __always_inline int trace_get_context_bit(void)
 454 {
 455         int bit;
 456
 457         if (in_interrupt()) {
 458                 if (in_nmi())
 459                         bit = 0;
 460
 461                 else if (in_irq())
 462                         bit = 1;
 463                 else
 464                         bit = 2;
 465         } else
 466                 bit = 3;
 467
 468         return bit;
 469 }
 470
 471 static __always_inline int trace_test_and_set_recursion(int start, int max)
 472 {
 473         unsigned int val = current->trace_recursion;
 474         int bit;
 475
 476         /* A previous recursion check was made */
 477         if ((val & TRACE_CONTEXT_MASK) > max)
 478                 return 0;
 479
 480         bit = trace_get_context_bit() + start;
 481         if (unlikely(val & (1 << bit)))
 482                 return -1;
 483
 484         val |= 1 << bit;
 485         current->trace_recursion = val;
 486         barrier();
 487
 488         return bit;
 489 }
 490
 491 static __always_inline void trace_clear_recursion(int bit)
 492 {
 493         unsigned int val = current->trace_recursion;
 494
 495         if (!bit)
 496                 return;
 497
 498         bit = 1 << bit;
 499         val &= ~bit;
 500
 501         barrier();
 502         current->trace_recursion = val;
 503 }
 504
 505 static inline struct ring_buffer_iter *
 506 trace_buffer_iter(struct trace_iterator *iter, int cpu)
 507 {
 508         if (iter->buffer_iter && iter->buffer_iter[cpu])
 509                 return iter->buffer_iter[cpu];
 510         return NULL;
 511 }
 512
 513 int tracer_init(struct tracer *t, struct trace_array *tr);
 514 int tracing_is_enabled(void);
 515 void tracing_reset(struct trace_buffer *buf, int cpu);
 516 void tracing_reset_online_cpus(struct trace_buffer *buf);
 517 void tracing_reset_current(int cpu);
 518 void tracing_reset_all_online_cpus(void);
 519 int tracing_open_generic(struct inode *inode, struct file *filp);
 520 struct dentry *trace_create_file(const char *name,
 521                                  umode_t mode,
 522                                  struct dentry *parent,
 523                                  void *data,
 524                                  const struct file_operations *fops);
 525
 526 struct dentry *tracing_init_dentry_tr(struct trace_array *tr);
 527 struct dentry *tracing_init_dentry(void);
 528
 529 struct ring_buffer_event;
 530
 531 struct ring_buffer_event *
 532 trace_buffer_lock_reserve(struct ring_buffer *buffer,
 533                           int type,
 534                           unsigned long len,
 535                           unsigned long flags,
 536                           int pc);
 537
 538 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
 539                                                 struct trace_array_cpu *data);
 540
 541 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
 542                                           int *ent_cpu, u64 *ent_ts);
 543
 544 void __buffer_unlock_commit(struct ring_buffer *buffer,
 545                             struct ring_buffer_event *event);
 546
 547 int trace_empty(struct trace_iterator *iter);
 548
 549 void *trace_find_next_entry_inc(struct trace_iterator *iter);
 550
 551 void trace_init_global_iter(struct trace_iterator *iter);
 552
 553 void tracing_iter_reset(struct trace_iterator *iter, int cpu);
 554
 555 void poll_wait_pipe(struct trace_iterator *iter);
 556
 557 void ftrace(struct trace_array *tr,
 558                             struct trace_array_cpu *data,
 559                             unsigned long ip,
 560                             unsigned long parent_ip,
 561                             unsigned long flags, int pc);
 562 void tracing_sched_switch_trace(struct trace_array *tr,
 563                                 struct task_struct *prev,
 564                                 struct task_struct *next,
 565                                 unsigned long flags, int pc);
 566
 567 void tracing_sched_wakeup_trace(struct trace_array *tr,
 568                                 struct task_struct *wakee,
 569                                 struct task_struct *cur,
 570                                 unsigned long flags, int pc);
 571 void trace_function(struct trace_array *tr,
 572                     unsigned long ip,
 573                     unsigned long parent_ip,
 574                     unsigned long flags, int pc);
 575 void trace_graph_function(struct trace_array *tr,
 576                     unsigned long ip,
 577                     unsigned long parent_ip,
 578                     unsigned long flags, int pc);
 579 void trace_latency_header(struct seq_file *m);
 580 void trace_default_header(struct seq_file *m);
 581 void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
 582 int trace_empty(struct trace_iterator *iter);
 583
 584 void trace_graph_return(struct ftrace_graph_ret *trace);
 585 int trace_graph_entry(struct ftrace_graph_ent *trace);
 586 void set_graph_array(struct trace_array *tr);
 587
 588 void tracing_start_cmdline_record(void);
 589 void tracing_stop_cmdline_record(void);
 590 void tracing_sched_switch_assign_trace(struct trace_array *tr);
 591 void tracing_stop_sched_switch_record(void);
 592 void tracing_start_sched_switch_record(void);
 593 int register_tracer(struct tracer *type);
 594 int is_tracing_stopped(void);
 595
 596 extern cpumask_var_t __read_mostly tracing_buffer_mask;
 597
 598 #define for_each_tracing_cpu(cpu)       \
 599         for_each_cpu(cpu, tracing_buffer_mask)
 600
 601 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
 602
 603 extern unsigned long tracing_thresh;
 604
 605 #ifdef CONFIG_TRACER_MAX_TRACE
 606 extern unsigned long tracing_max_latency;
 607
 608 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu);
 609 void update_max_tr_single(struct trace_array *tr,
 610                           struct task_struct *tsk, int cpu);
 611 #endif /* CONFIG_TRACER_MAX_TRACE */
 612
 613 #ifdef CONFIG_STACKTRACE
 614 void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags,
 615                         int skip, int pc);
 616
 617 void ftrace_trace_stack_regs(struct ring_buffer *buffer, unsigned long flags,
 618                              int skip, int pc, struct pt_regs *regs);
 619
 620 void ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags,
 621                             int pc);
 622
 623 void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
 624                    int pc);
 625 #else
 626 static inline void ftrace_trace_stack(struct ring_buffer *buffer,
 627                                       unsigned long flags, int skip, int pc)
 628 {
 629 }
 630
 631 static inline void ftrace_trace_stack_regs(struct ring_buffer *buffer,
 632                                            unsigned long flags, int skip,
 633                                            int pc, struct pt_regs *regs)
 634 {
 635 }
 636
 637 static inline void ftrace_trace_userstack(struct ring_buffer *buffer,
 638                                           unsigned long flags, int pc)
 639 {
 640 }
 641
 642 static inline void __trace_stack(struct trace_array *tr, unsigned long flags,
 643                                  int skip, int pc)
 644 {
 645 }
 646 #endif /* CONFIG_STACKTRACE */
 647
 648 extern cycle_t ftrace_now(int cpu);
 649
 650 extern void trace_find_cmdline(int pid, char comm[]);
 651
 652 #ifdef CONFIG_DYNAMIC_FTRACE
 653 extern unsigned long ftrace_update_tot_cnt;
 654 #endif
 655 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
 656 extern int DYN_FTRACE_TEST_NAME(void);
 657 #define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
 658 extern int DYN_FTRACE_TEST_NAME2(void);
 659
 660 extern bool ring_buffer_expanded;
 661 extern bool tracing_selftest_disabled;
 662 DECLARE_PER_CPU(int, ftrace_cpu_disabled);
 663
 664 #ifdef CONFIG_FTRACE_STARTUP_TEST
 665 extern int trace_selftest_startup_function(struct tracer *trace,
 666                                            struct trace_array *tr);
 667 extern int trace_selftest_startup_function_graph(struct tracer *trace,
 668                                                  struct trace_array *tr);
 669 extern int trace_selftest_startup_irqsoff(struct tracer *trace,
 670                                           struct trace_array *tr);
 671 extern int trace_selftest_startup_preemptoff(struct tracer *trace,
 672                                              struct trace_array *tr);
 673 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
 674                                                  struct trace_array *tr);
 675 extern int trace_selftest_startup_wakeup(struct tracer *trace,
 676                                          struct trace_array *tr);
 677 extern int trace_selftest_startup_nop(struct tracer *trace,
 678                                          struct trace_array *tr);
 679 extern int trace_selftest_startup_sched_switch(struct tracer *trace,
 680                                                struct trace_array *tr);
 681 extern int trace_selftest_startup_branch(struct tracer *trace,
 682                                          struct trace_array *tr);
 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 static inline int ftrace_trace_task(struct task_struct *task)
 778 {
 779         if (list_empty(&ftrace_pids))
 780                 return 1;
 781
 782         return test_tsk_trace_trace(task);
 783 }
 784 extern int ftrace_is_dead(void);
 785 #else
 786 static inline int ftrace_trace_task(struct task_struct *task)
 787 {
 788         return 1;
 789 }
 790 static inline int ftrace_is_dead(void) { return 0; }
 791 #endif
 792
 793 int ftrace_event_is_function(struct ftrace_event_call *call);
 794
 795 /*
 796  * struct trace_parser - servers for reading the user input separated by spaces
 797  * @cont: set if the input is not complete - no final space char was found
 798  * @buffer: holds the parsed user input
 799  * @idx: user input length
 800  * @size: buffer size
 801  */
 802 struct trace_parser {
 803         bool            cont;
 804         char            *buffer;
 805         unsigned        idx;
 806         unsigned        size;
 807 };
 808
 809 static inline bool trace_parser_loaded(struct trace_parser *parser)
 810 {
 811         return (parser->idx != 0);
 812 }
 813
 814 static inline bool trace_parser_cont(struct trace_parser *parser)
 815 {
 816         return parser->cont;
 817 }
 818
 819 static inline void trace_parser_clear(struct trace_parser *parser)
 820 {
 821         parser->cont = false;
 822         parser->idx = 0;
 823 }
 824
 825 extern int trace_parser_get_init(struct trace_parser *parser, int size);
 826 extern void trace_parser_put(struct trace_parser *parser);
 827 extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
 828         size_t cnt, loff_t *ppos);
 829
 830 /*
 831  * trace_iterator_flags is an enumeration that defines bit
 832  * positions into trace_flags that controls the output.
 833  *
 834  * NOTE: These bits must match the trace_options array in
 835  *       trace.c.
 836  */
 837 enum trace_iterator_flags {
 838         TRACE_ITER_PRINT_PARENT         = 0x01,
 839         TRACE_ITER_SYM_OFFSET           = 0x02,
 840         TRACE_ITER_SYM_ADDR             = 0x04,
 841         TRACE_ITER_VERBOSE              = 0x08,
 842         TRACE_ITER_RAW                  = 0x10,
 843         TRACE_ITER_HEX                  = 0x20,
 844         TRACE_ITER_BIN                  = 0x40,
 845         TRACE_ITER_BLOCK                = 0x80,
 846         TRACE_ITER_STACKTRACE           = 0x100,
 847         TRACE_ITER_PRINTK               = 0x200,
 848         TRACE_ITER_PREEMPTONLY          = 0x400,
 849         TRACE_ITER_BRANCH               = 0x800,
 850         TRACE_ITER_ANNOTATE             = 0x1000,
 851         TRACE_ITER_USERSTACKTRACE       = 0x2000,
 852         TRACE_ITER_SYM_USEROBJ          = 0x4000,
 853         TRACE_ITER_PRINTK_MSGONLY       = 0x8000,
 854         TRACE_ITER_CONTEXT_INFO         = 0x10000, /* Print pid/cpu/time */
 855         TRACE_ITER_LATENCY_FMT          = 0x20000,
 856         TRACE_ITER_SLEEP_TIME           = 0x40000,
 857         TRACE_ITER_GRAPH_TIME           = 0x80000,
 858         TRACE_ITER_RECORD_CMD           = 0x100000,
 859         TRACE_ITER_OVERWRITE            = 0x200000,
 860         TRACE_ITER_STOP_ON_FREE         = 0x400000,
 861         TRACE_ITER_IRQ_INFO             = 0x800000,
 862         TRACE_ITER_MARKERS              = 0x1000000,
 863         TRACE_ITER_FUNCTION             = 0x2000000,
 864 };
 865
 866 /*
 867  * TRACE_ITER_SYM_MASK masks the options in trace_flags that
 868  * control the output of kernel symbols.
 869  */
 870 #define TRACE_ITER_SYM_MASK \
 871         (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
 872
 873 extern struct tracer nop_trace;
 874
 875 #ifdef CONFIG_BRANCH_TRACER
 876 extern int enable_branch_tracing(struct trace_array *tr);
 877 extern void disable_branch_tracing(void);
 878 static inline int trace_branch_enable(struct trace_array *tr)
 879 {
 880         if (trace_flags & TRACE_ITER_BRANCH)
 881                 return enable_branch_tracing(tr);
 882         return 0;
 883 }
 884 static inline void trace_branch_disable(void)
 885 {
 886         /* due to races, always disable */
 887         disable_branch_tracing();
 888 }
 889 #else
 890 static inline int trace_branch_enable(struct trace_array *tr)
 891 {
 892         return 0;
 893 }
 894 static inline void trace_branch_disable(void)
 895 {
 896 }
 897 #endif /* CONFIG_BRANCH_TRACER */
 898
 899 /* set ring buffers to default size if not already done so */
 900 int tracing_update_buffers(void);
 901
 902 /* trace event type bit fields, not numeric */
 903 enum {
 904         TRACE_EVENT_TYPE_PRINTF         = 1,
 905         TRACE_EVENT_TYPE_RAW            = 2,
 906 };
 907
 908 struct ftrace_event_field {
 909         struct list_head        link;
 910         const char              *name;
 911         const char              *type;
 912         int                     filter_type;
 913         int                     offset;
 914         int                     size;
 915         int                     is_signed;
 916 };
 917
 918 struct event_filter {
 919         int                     n_preds;        /* Number assigned */
 920         int                     a_preds;        /* allocated */
 921         struct filter_pred      *preds;
 922         struct filter_pred      *root;
 923         char                    *filter_string;
 924 };
 925
 926 struct event_subsystem {
 927         struct list_head        list;
 928         const char              *name;
 929         struct event_filter     *filter;
 930         int                     ref_count;
 931 };
 932
 933 struct ftrace_subsystem_dir {
 934         struct list_head                list;
 935         struct event_subsystem          *subsystem;
 936         struct trace_array              *tr;
 937         struct dentry                   *entry;
 938         int                             ref_count;
 939         int                             nr_events;
 940 };
 941
 942 #define FILTER_PRED_INVALID     ((unsigned short)-1)
 943 #define FILTER_PRED_IS_RIGHT    (1 << 15)
 944 #define FILTER_PRED_FOLD        (1 << 15)
 945
 946 /*
 947  * The max preds is the size of unsigned short with
 948  * two flags at the MSBs. One bit is used for both the IS_RIGHT
 949  * and FOLD flags. The other is reserved.
 950  *
 951  * 2^14 preds is way more than enough.
 952  */
 953 #define MAX_FILTER_PRED         16384
 954
 955 struct filter_pred;
 956 struct regex;
 957
 958 typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event);
 959
 960 typedef int (*regex_match_func)(char *str, struct regex *r, int len);
 961
 962 enum regex_type {
 963         MATCH_FULL = 0,
 964         MATCH_FRONT_ONLY,
 965         MATCH_MIDDLE_ONLY,
 966         MATCH_END_ONLY,
 967 };
 968
 969 struct regex {
 970         char                    pattern[MAX_FILTER_STR_VAL];
 971         int                     len;
 972         int                     field_len;
 973         regex_match_func        match;
 974 };
 975
 976 struct filter_pred {
 977         filter_pred_fn_t        fn;
 978         u64                     val;
 979         struct regex            regex;
 980         unsigned short          *ops;
 981         struct ftrace_event_field *field;
 982         int                     offset;
 983         int                     not;
 984         int                     op;
 985         unsigned short          index;
 986         unsigned short          parent;
 987         unsigned short          left;
 988         unsigned short          right;
 989 };
 990
 991 extern enum regex_type
 992 filter_parse_regex(char *buff, int len, char **search, int *not);
 993 extern void print_event_filter(struct ftrace_event_call *call,
 994                                struct trace_seq *s);
 995 extern int apply_event_filter(struct ftrace_event_call *call,
 996                               char *filter_string);
 997 extern int apply_subsystem_event_filter(struct ftrace_subsystem_dir *dir,
 998                                         char *filter_string);
 999 extern void print_subsystem_event_filter(struct event_subsystem *system,
1000                                          struct trace_seq *s);
1001 extern int filter_assign_type(const char *type);
1002
1003 struct ftrace_event_field *
1004 trace_find_event_field(struct ftrace_event_call *call, char *name);
1005
1006 static inline int
1007 filter_check_discard(struct ftrace_event_call *call, void *rec,
1008                      struct ring_buffer *buffer,
1009                      struct ring_buffer_event *event)
1010 {
1011         if (unlikely(call->flags & TRACE_EVENT_FL_FILTERED) &&
1012             !filter_match_preds(call->filter, rec)) {
1013                 ring_buffer_discard_commit(buffer, event);
1014                 return 1;
1015         }
1016
1017         return 0;
1018 }
1019
1020 extern void trace_event_enable_cmd_record(bool enable);
1021 extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr);
1022 extern int event_trace_del_tracer(struct trace_array *tr);
1023
1024 extern struct mutex event_mutex;
1025 extern struct list_head ftrace_events;
1026
1027 extern const char *__start___trace_bprintk_fmt[];
1028 extern const char *__stop___trace_bprintk_fmt[];
1029
1030 void trace_printk_init_buffers(void);
1031 void trace_printk_start_comm(void);
1032 int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set);
1033 int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled);
1034
1035 /*
1036  * Normal trace_printk() and friends allocates special buffers
1037  * to do the manipulation, as well as saves the print formats
1038  * into sections to display. But the trace infrastructure wants
1039  * to use these without the added overhead at the price of being
1040  * a bit slower (used mainly for warnings, where we don't care
1041  * about performance). The internal_trace_puts() is for such
1042  * a purpose.
1043  */
1044 #define internal_trace_puts(str) __trace_puts(_THIS_IP_, str, strlen(str))
1045
1046 #undef FTRACE_ENTRY
1047 #define FTRACE_ENTRY(call, struct_name, id, tstruct, print, filter)     \
1048         extern struct ftrace_event_call                                 \
1049         __attribute__((__aligned__(4))) event_##call;
1050 #undef FTRACE_ENTRY_DUP
1051 #define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print, filter) \
1052         FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print), \
1053                      filter)
1054 #include "trace_entries.h"
1055
1056 #if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER)
1057 int perf_ftrace_event_register(struct ftrace_event_call *call,
1058                                enum trace_reg type, void *data);
1059 #else
1060 #define perf_ftrace_event_register NULL
1061 #endif
1062
1063 #endif /* _LINUX_KERNEL_TRACE_H */