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         TRACE_FLAG_PREEMPT_RESCHED      = 0x20,
 128 };
 129
 130 #define TRACE_BUF_SIZE          1024
 131
 132 struct trace_array;
 133
 134 /*
 135  * The CPU trace array - it consists of thousands of trace entries
 136  * plus some other descriptor data: (for example which task started
 137  * the trace, etc.)
 138  */
 139 struct trace_array_cpu {
 140         atomic_t                disabled;
 141         void                    *buffer_page;   /* ring buffer spare */
 142
 143         unsigned long           entries;
 144         unsigned long           saved_latency;
 145         unsigned long           critical_start;
 146         unsigned long           critical_end;
 147         unsigned long           critical_sequence;
 148         unsigned long           nice;
 149         unsigned long           policy;
 150         unsigned long           rt_priority;
 151         unsigned long           skipped_entries;
 152         cycle_t                 preempt_timestamp;
 153         pid_t                   pid;
 154         kuid_t                  uid;
 155         char                    comm[TASK_COMM_LEN];
 156 };
 157
 158 struct tracer;
 159
 160 struct trace_buffer {
 161         struct trace_array              *tr;
 162         struct ring_buffer              *buffer;
 163         struct trace_array_cpu __percpu *data;
 164         cycle_t                         time_start;
 165         int                             cpu;
 166 };
 167
 168 /*
 169  * The trace array - an array of per-CPU trace arrays. This is the
 170  * highest level data structure that individual tracers deal with.
 171  * They have on/off state as well:
 172  */
 173 struct trace_array {
 174         struct list_head        list;
 175         char                    *name;
 176         struct trace_buffer     trace_buffer;
 177 #ifdef CONFIG_TRACER_MAX_TRACE
 178         /*
 179          * The max_buffer is used to snapshot the trace when a maximum
 180          * latency is reached, or when the user initiates a snapshot.
 181          * Some tracers will use this to store a maximum trace while
 182          * it continues examining live traces.
 183          *
 184          * The buffers for the max_buffer are set up the same as the trace_buffer
 185          * When a snapshot is taken, the buffer of the max_buffer is swapped
 186          * with the buffer of the trace_buffer and the buffers are reset for
 187          * the trace_buffer so the tracing can continue.
 188          */
 189         struct trace_buffer     max_buffer;
 190         bool                    allocated_snapshot;
 191 #endif
 192         int                     buffer_disabled;
 193 #ifdef CONFIG_FTRACE_SYSCALLS
 194         int                     sys_refcount_enter;
 195         int                     sys_refcount_exit;
 196         struct ftrace_event_file __rcu *enter_syscall_files[NR_syscalls];
 197         struct ftrace_event_file __rcu *exit_syscall_files[NR_syscalls];
 198 #endif
 199         int                     stop_count;
 200         int                     clock_id;
 201         struct tracer           *current_trace;
 202         unsigned int            flags;
 203         raw_spinlock_t          start_lock;
 204         struct dentry           *dir;
 205         struct dentry           *options;
 206         struct dentry           *percpu_dir;
 207         struct dentry           *event_dir;
 208         struct list_head        systems;
 209         struct list_head        events;
 210         cpumask_var_t           tracing_cpumask; /* only trace on set CPUs */
 211         int                     ref;
 212 };
 213
 214 enum {
 215         TRACE_ARRAY_FL_GLOBAL   = (1 << 0)
 216 };
 217
 218 extern struct list_head ftrace_trace_arrays;
 219
 220 extern struct mutex trace_types_lock;
 221
 222 extern int trace_array_get(struct trace_array *tr);
 223 extern void trace_array_put(struct trace_array *tr);
 224
 225 /*
 226  * The global tracer (top) should be the first trace array added,
 227  * but we check the flag anyway.
 228  */
 229 static inline struct trace_array *top_trace_array(void)
 230 {
 231         struct trace_array *tr;
 232
 233         tr = list_entry(ftrace_trace_arrays.prev,
 234                         typeof(*tr), list);
 235         WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL));
 236         return tr;
 237 }
 238
 239 #define FTRACE_CMP_TYPE(var, type) \
 240         __builtin_types_compatible_p(typeof(var), type *)
 241
 242 #undef IF_ASSIGN
 243 #define IF_ASSIGN(var, entry, etype, id)                \
 244         if (FTRACE_CMP_TYPE(var, etype)) {              \
 245                 var = (typeof(var))(entry);             \
 246                 WARN_ON(id && (entry)->type != id);     \
 247                 break;                                  \
 248         }
 249
 250 /* Will cause compile errors if type is not found. */
 251 extern void __ftrace_bad_type(void);
 252
 253 /*
 254  * The trace_assign_type is a verifier that the entry type is
 255  * the same as the type being assigned. To add new types simply
 256  * add a line with the following format:
 257  *
 258  * IF_ASSIGN(var, ent, type, id);
 259  *
 260  *  Where "type" is the trace type that includes the trace_entry
 261  *  as the "ent" item. And "id" is the trace identifier that is
 262  *  used in the trace_type enum.
 263  *
 264  *  If the type can have more than one id, then use zero.
 265  */
 266 #define trace_assign_type(var, ent)                                     \
 267         do {                                                            \
 268                 IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN);     \
 269                 IF_ASSIGN(var, ent, struct ctx_switch_entry, 0);        \
 270                 IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK);   \
 271                 IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
 272                 IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT);   \
 273                 IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT); \
 274                 IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS);   \
 275                 IF_ASSIGN(var, ent, struct trace_mmiotrace_rw,          \
 276                           TRACE_MMIO_RW);                               \
 277                 IF_ASSIGN(var, ent, struct trace_mmiotrace_map,         \
 278                           TRACE_MMIO_MAP);                              \
 279                 IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
 280                 IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry,      \
 281                           TRACE_GRAPH_ENT);             \
 282                 IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry,      \
 283                           TRACE_GRAPH_RET);             \
 284                 __ftrace_bad_type();                                    \
 285         } while (0)
 286
 287 /*
 288  * An option specific to a tracer. This is a boolean value.
 289  * The bit is the bit index that sets its value on the
 290  * flags value in struct tracer_flags.
 291  */
 292 struct tracer_opt {
 293         const char      *name; /* Will appear on the trace_options file */
 294         u32             bit; /* Mask assigned in val field in tracer_flags */
 295 };
 296
 297 /*
 298  * The set of specific options for a tracer. Your tracer
 299  * have to set the initial value of the flags val.
 300  */
 301 struct tracer_flags {
 302         u32                     val;
 303         struct tracer_opt       *opts;
 304 };
 305
 306 /* Makes more easy to define a tracer opt */
 307 #define TRACER_OPT(s, b)        .name = #s, .bit = b
 308
 309
 310 /**
 311  * struct tracer - a specific tracer and its callbacks to interact with debugfs
 312  * @name: the name chosen to select it on the available_tracers file
 313  * @init: called when one switches to this tracer (echo name > current_tracer)
 314  * @reset: called when one switches to another tracer
 315  * @start: called when tracing is unpaused (echo 1 > tracing_enabled)
 316  * @stop: called when tracing is paused (echo 0 > tracing_enabled)
 317  * @open: called when the trace file is opened
 318  * @pipe_open: called when the trace_pipe file is opened
 319  * @wait_pipe: override how the user waits for traces on trace_pipe
 320  * @close: called when the trace file is released
 321  * @pipe_close: called when the trace_pipe file is released
 322  * @read: override the default read callback on trace_pipe
 323  * @splice_read: override the default splice_read callback on trace_pipe
 324  * @selftest: selftest to run on boot (see trace_selftest.c)
 325  * @print_headers: override the first lines that describe your columns
 326  * @print_line: callback that prints a trace
 327  * @set_flag: signals one of your private flags changed (trace_options file)
 328  * @flags: your private flags
 329  */
 330 struct tracer {
 331         const char              *name;
 332         int                     (*init)(struct trace_array *tr);
 333         void                    (*reset)(struct trace_array *tr);
 334         void                    (*start)(struct trace_array *tr);
 335         void                    (*stop)(struct trace_array *tr);
 336         void                    (*open)(struct trace_iterator *iter);
 337         void                    (*pipe_open)(struct trace_iterator *iter);
 338         void                    (*wait_pipe)(struct trace_iterator *iter);
 339         void                    (*close)(struct trace_iterator *iter);
 340         void                    (*pipe_close)(struct trace_iterator *iter);
 341         ssize_t                 (*read)(struct trace_iterator *iter,
 342                                         struct file *filp, char __user *ubuf,
 343                                         size_t cnt, loff_t *ppos);
 344         ssize_t                 (*splice_read)(struct trace_iterator *iter,
 345                                                struct file *filp,
 346                                                loff_t *ppos,
 347                                                struct pipe_inode_info *pipe,
 348                                                size_t len,
 349                                                unsigned int flags);
 350 #ifdef CONFIG_FTRACE_STARTUP_TEST
 351         int                     (*selftest)(struct tracer *trace,
 352                                             struct trace_array *tr);
 353 #endif
 354         void                    (*print_header)(struct seq_file *m);
 355         enum print_line_t       (*print_line)(struct trace_iterator *iter);
 356         /* If you handled the flag setting, return 0 */
 357         int                     (*set_flag)(u32 old_flags, u32 bit, int set);
 358         /* Return 0 if OK with change, else return non-zero */
 359         int                     (*flag_changed)(struct tracer *tracer,
 360                                                 u32 mask, int set);
 361         struct tracer           *next;
 362         struct tracer_flags     *flags;
 363         bool                    print_max;
 364         bool                    enabled;
 365 #ifdef CONFIG_TRACER_MAX_TRACE
 366         bool                    use_max_tr;
 367 #endif
 368 };
 369
 370
 371 /* Only current can touch trace_recursion */
 372
 373 /*
 374  * For function tracing recursion:
 375  *  The order of these bits are important.
 376  *
 377  *  When function tracing occurs, the following steps are made:
 378  *   If arch does not support a ftrace feature:
 379  *    call internal function (uses INTERNAL bits) which calls...
 380  *   If callback is registered to the "global" list, the list
 381  *    function is called and recursion checks the GLOBAL bits.
 382  *    then this function calls...
 383  *   The function callback, which can use the FTRACE bits to
 384  *    check for recursion.
 385  *
 386  * Now if the arch does not suppport a feature, and it calls
 387  * the global list function which calls the ftrace callback
 388  * all three of these steps will do a recursion protection.
 389  * There's no reason to do one if the previous caller already
 390  * did. The recursion that we are protecting against will
 391  * go through the same steps again.
 392  *
 393  * To prevent the multiple recursion checks, if a recursion
 394  * bit is set that is higher than the MAX bit of the current
 395  * check, then we know that the check was made by the previous
 396  * caller, and we can skip the current check.
 397  */
 398 enum {
 399         TRACE_BUFFER_BIT,
 400         TRACE_BUFFER_NMI_BIT,
 401         TRACE_BUFFER_IRQ_BIT,
 402         TRACE_BUFFER_SIRQ_BIT,
 403
 404         /* Start of function recursion bits */
 405         TRACE_FTRACE_BIT,
 406         TRACE_FTRACE_NMI_BIT,
 407         TRACE_FTRACE_IRQ_BIT,
 408         TRACE_FTRACE_SIRQ_BIT,
 409
 410         /* GLOBAL_BITs must be greater than FTRACE_BITs */
 411         TRACE_GLOBAL_BIT,
 412         TRACE_GLOBAL_NMI_BIT,
 413         TRACE_GLOBAL_IRQ_BIT,
 414         TRACE_GLOBAL_SIRQ_BIT,
 415
 416         /* INTERNAL_BITs must be greater than GLOBAL_BITs */
 417         TRACE_INTERNAL_BIT,
 418         TRACE_INTERNAL_NMI_BIT,
 419         TRACE_INTERNAL_IRQ_BIT,
 420         TRACE_INTERNAL_SIRQ_BIT,
 421
 422         TRACE_CONTROL_BIT,
 423
 424 /*
 425  * Abuse of the trace_recursion.
 426  * As we need a way to maintain state if we are tracing the function
 427  * graph in irq because we want to trace a particular function that
 428  * was called in irq context but we have irq tracing off. Since this
 429  * can only be modified by current, we can reuse trace_recursion.
 430  */
 431         TRACE_IRQ_BIT,
 432 };
 433
 434 #define trace_recursion_set(bit)        do { (current)->trace_recursion |= (1<<(bit)); } while (0)
 435 #define trace_recursion_clear(bit)      do { (current)->trace_recursion &= ~(1<<(bit)); } while (0)
 436 #define trace_recursion_test(bit)       ((current)->trace_recursion & (1<<(bit)))
 437
 438 #define TRACE_CONTEXT_BITS      4
 439
 440 #define TRACE_FTRACE_START      TRACE_FTRACE_BIT
 441 #define TRACE_FTRACE_MAX        ((1 << (TRACE_FTRACE_START + TRACE_CONTEXT_BITS)) - 1)
 442
 443 #define TRACE_GLOBAL_START      TRACE_GLOBAL_BIT
 444 #define TRACE_GLOBAL_MAX        ((1 << (TRACE_GLOBAL_START + TRACE_CONTEXT_BITS)) - 1)
 445
 446 #define TRACE_LIST_START        TRACE_INTERNAL_BIT
 447 #define TRACE_LIST_MAX          ((1 << (TRACE_LIST_START + TRACE_CONTEXT_BITS)) - 1)
 448
 449 #define TRACE_CONTEXT_MASK      TRACE_LIST_MAX
 450
 451 static __always_inline int trace_get_context_bit(void)
 452 {
 453         int bit;
 454
 455         if (in_interrupt()) {
 456                 if (in_nmi())
 457                         bit = 0;
 458
 459                 else if (in_irq())
 460                         bit = 1;
 461                 else
 462                         bit = 2;
 463         } else
 464                 bit = 3;
 465
 466         return bit;
 467 }
 468
 469 static __always_inline int trace_test_and_set_recursion(int start, int max)
 470 {
 471         unsigned int val = current->trace_recursion;
 472         int bit;
 473
 474         /* A previous recursion check was made */
 475         if ((val & TRACE_CONTEXT_MASK) > max)
 476                 return 0;
 477
 478         bit = trace_get_context_bit() + start;
 479         if (unlikely(val & (1 << bit)))
 480                 return -1;
 481
 482         val |= 1 << bit;
 483         current->trace_recursion = val;
 484         barrier();
 485
 486         return bit;
 487 }
 488
 489 static __always_inline void trace_clear_recursion(int bit)
 490 {
 491         unsigned int val = current->trace_recursion;
 492
 493         if (!bit)
 494                 return;
 495
 496         bit = 1 << bit;
 497         val &= ~bit;
 498
 499         barrier();
 500         current->trace_recursion = val;
 501 }
 502
 503 static inline struct ring_buffer_iter *
 504 trace_buffer_iter(struct trace_iterator *iter, int cpu)
 505 {
 506         if (iter->buffer_iter && iter->buffer_iter[cpu])
 507                 return iter->buffer_iter[cpu];
 508         return NULL;
 509 }
 510
 511 int tracer_init(struct tracer *t, struct trace_array *tr);
 512 int tracing_is_enabled(void);
 513 void tracing_reset(struct trace_buffer *buf, int cpu);
 514 void tracing_reset_online_cpus(struct trace_buffer *buf);
 515 void tracing_reset_current(int cpu);
 516 void tracing_reset_all_online_cpus(void);
 517 int tracing_open_generic(struct inode *inode, struct file *filp);
 518 bool tracing_is_disabled(void);
 519 struct dentry *trace_create_file(const char *name,
 520                                  umode_t mode,
 521                                  struct dentry *parent,
 522                                  void *data,
 523                                  const struct file_operations *fops);
 524
 525 struct dentry *tracing_init_dentry_tr(struct trace_array *tr);
 526 struct dentry *tracing_init_dentry(void);
 527
 528 struct ring_buffer_event;
 529
 530 struct ring_buffer_event *
 531 trace_buffer_lock_reserve(struct ring_buffer *buffer,
 532                           int type,
 533                           unsigned long len,
 534                           unsigned long flags,
 535                           int pc);
 536
 537 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
 538                                                 struct trace_array_cpu *data);
 539
 540 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
 541                                           int *ent_cpu, u64 *ent_ts);
 542
 543 void __buffer_unlock_commit(struct ring_buffer *buffer,
 544                             struct ring_buffer_event *event);
 545
 546 int trace_empty(struct trace_iterator *iter);
 547
 548 void *trace_find_next_entry_inc(struct trace_iterator *iter);
 549
 550 void trace_init_global_iter(struct trace_iterator *iter);
 551
 552 void tracing_iter_reset(struct trace_iterator *iter, int cpu);
 553
 554 void poll_wait_pipe(struct trace_iterator *iter);
 555
 556 void tracing_sched_switch_trace(struct trace_array *tr,
 557                                 struct task_struct *prev,
 558                                 struct task_struct *next,
 559                                 unsigned long flags, int pc);
 560
 561 void tracing_sched_wakeup_trace(struct trace_array *tr,
 562                                 struct task_struct *wakee,
 563                                 struct task_struct *cur,
 564                                 unsigned long flags, int pc);
 565 void trace_function(struct trace_array *tr,
 566                     unsigned long ip,
 567                     unsigned long parent_ip,
 568                     unsigned long flags, int pc);
 569 void trace_graph_function(struct trace_array *tr,
 570                     unsigned long ip,
 571                     unsigned long parent_ip,
 572                     unsigned long flags, int pc);
 573 void trace_latency_header(struct seq_file *m);
 574 void trace_default_header(struct seq_file *m);
 575 void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
 576 int trace_empty(struct trace_iterator *iter);
 577
 578 void trace_graph_return(struct ftrace_graph_ret *trace);
 579 int trace_graph_entry(struct ftrace_graph_ent *trace);
 580 void set_graph_array(struct trace_array *tr);
 581
 582 void tracing_start_cmdline_record(void);
 583 void tracing_stop_cmdline_record(void);
 584 void tracing_sched_switch_assign_trace(struct trace_array *tr);
 585 void tracing_stop_sched_switch_record(void);
 586 void tracing_start_sched_switch_record(void);
 587 int register_tracer(struct tracer *type);
 588 int is_tracing_stopped(void);
 589
 590 extern cpumask_var_t __read_mostly tracing_buffer_mask;
 591
 592 #define for_each_tracing_cpu(cpu)       \
 593         for_each_cpu(cpu, tracing_buffer_mask)
 594
 595 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
 596
 597 extern unsigned long tracing_thresh;
 598
 599 #ifdef CONFIG_TRACER_MAX_TRACE
 600 extern unsigned long tracing_max_latency;
 601
 602 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu);
 603 void update_max_tr_single(struct trace_array *tr,
 604                           struct task_struct *tsk, int cpu);
 605 #endif /* CONFIG_TRACER_MAX_TRACE */
 606
 607 #ifdef CONFIG_STACKTRACE
 608 void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags,
 609                         int skip, int pc);
 610
 611 void ftrace_trace_stack_regs(struct ring_buffer *buffer, unsigned long flags,
 612                              int skip, int pc, struct pt_regs *regs);
 613
 614 void ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags,
 615                             int pc);
 616
 617 void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
 618                    int pc);
 619 #else
 620 static inline void ftrace_trace_stack(struct ring_buffer *buffer,
 621                                       unsigned long flags, int skip, int pc)
 622 {
 623 }
 624
 625 static inline void ftrace_trace_stack_regs(struct ring_buffer *buffer,
 626                                            unsigned long flags, int skip,
 627                                            int pc, struct pt_regs *regs)
 628 {
 629 }
 630
 631 static inline void ftrace_trace_userstack(struct ring_buffer *buffer,
 632                                           unsigned long flags, int pc)
 633 {
 634 }
 635
 636 static inline void __trace_stack(struct trace_array *tr, unsigned long flags,
 637                                  int skip, int pc)
 638 {
 639 }
 640 #endif /* CONFIG_STACKTRACE */
 641
 642 extern cycle_t ftrace_now(int cpu);
 643
 644 extern void trace_find_cmdline(int pid, char comm[]);
 645
 646 #ifdef CONFIG_DYNAMIC_FTRACE
 647 extern unsigned long ftrace_update_tot_cnt;
 648 #endif
 649 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
 650 extern int DYN_FTRACE_TEST_NAME(void);
 651 #define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
 652 extern int DYN_FTRACE_TEST_NAME2(void);
 653
 654 extern bool ring_buffer_expanded;
 655 extern bool tracing_selftest_disabled;
 656 DECLARE_PER_CPU(int, ftrace_cpu_disabled);
 657
 658 #ifdef CONFIG_FTRACE_STARTUP_TEST
 659 extern int trace_selftest_startup_function(struct tracer *trace,
 660                                            struct trace_array *tr);
 661 extern int trace_selftest_startup_function_graph(struct tracer *trace,
 662                                                  struct trace_array *tr);
 663 extern int trace_selftest_startup_irqsoff(struct tracer *trace,
 664                                           struct trace_array *tr);
 665 extern int trace_selftest_startup_preemptoff(struct tracer *trace,
 666                                              struct trace_array *tr);
 667 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
 668                                                  struct trace_array *tr);
 669 extern int trace_selftest_startup_wakeup(struct tracer *trace,
 670                                          struct trace_array *tr);
 671 extern int trace_selftest_startup_nop(struct tracer *trace,
 672                                          struct trace_array *tr);
 673 extern int trace_selftest_startup_sched_switch(struct tracer *trace,
 674                                                struct trace_array *tr);
 675 extern int trace_selftest_startup_branch(struct tracer *trace,
 676                                          struct trace_array *tr);
 677 /*
 678  * Tracer data references selftest functions that only occur
 679  * on boot up. These can be __init functions. Thus, when selftests
 680  * are enabled, then the tracers need to reference __init functions.
 681  */
 682 #define __tracer_data           __refdata
 683 #else
 684 /* Tracers are seldom changed. Optimize when selftests are disabled. */
 685 #define __tracer_data           __read_mostly
 686 #endif /* CONFIG_FTRACE_STARTUP_TEST */
 687
 688 extern void *head_page(struct trace_array_cpu *data);
 689 extern unsigned long long ns2usecs(cycle_t nsec);
 690 extern int
 691 trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
 692 extern int
 693 trace_vprintk(unsigned long ip, const char *fmt, va_list args);
 694 extern int
 695 trace_array_vprintk(struct trace_array *tr,
 696                     unsigned long ip, const char *fmt, va_list args);
 697 int trace_array_printk(struct trace_array *tr,
 698                        unsigned long ip, const char *fmt, ...);
 699 int trace_array_printk_buf(struct ring_buffer *buffer,
 700                            unsigned long ip, const char *fmt, ...);
 701 void trace_printk_seq(struct trace_seq *s);
 702 enum print_line_t print_trace_line(struct trace_iterator *iter);
 703
 704 extern unsigned long trace_flags;
 705
 706 /* Standard output formatting function used for function return traces */
 707 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
 708
 709 /* Flag options */
 710 #define TRACE_GRAPH_PRINT_OVERRUN       0x1
 711 #define TRACE_GRAPH_PRINT_CPU           0x2
 712 #define TRACE_GRAPH_PRINT_OVERHEAD      0x4
 713 #define TRACE_GRAPH_PRINT_PROC          0x8
 714 #define TRACE_GRAPH_PRINT_DURATION      0x10
 715 #define TRACE_GRAPH_PRINT_ABS_TIME      0x20
 716 #define TRACE_GRAPH_PRINT_FILL_SHIFT    28
 717 #define TRACE_GRAPH_PRINT_FILL_MASK     (0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT)
 718
 719 extern enum print_line_t
 720 print_graph_function_flags(struct trace_iterator *iter, u32 flags);
 721 extern void print_graph_headers_flags(struct seq_file *s, u32 flags);
 722 extern enum print_line_t
 723 trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
 724 extern void graph_trace_open(struct trace_iterator *iter);
 725 extern void graph_trace_close(struct trace_iterator *iter);
 726 extern int __trace_graph_entry(struct trace_array *tr,
 727                                struct ftrace_graph_ent *trace,
 728                                unsigned long flags, int pc);
 729 extern void __trace_graph_return(struct trace_array *tr,
 730                                  struct ftrace_graph_ret *trace,
 731                                  unsigned long flags, int pc);
 732
 733
 734 #ifdef CONFIG_DYNAMIC_FTRACE
 735 /* TODO: make this variable */
 736 #define FTRACE_GRAPH_MAX_FUNCS          32
 737 extern int ftrace_graph_count;
 738 extern unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS];
 739 extern int ftrace_graph_notrace_count;
 740 extern unsigned long ftrace_graph_notrace_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_count)
 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
 767 static inline int ftrace_graph_notrace_addr(unsigned long addr)
 768 {
 769         int i;
 770
 771         if (!ftrace_graph_notrace_count)
 772                 return 0;
 773
 774         for (i = 0; i < ftrace_graph_notrace_count; i++) {
 775                 if (addr == ftrace_graph_notrace_funcs[i])
 776                         return 1;
 777         }
 778
 779         return 0;
 780 }
 781 #else
 782 static inline int ftrace_graph_addr(unsigned long addr)
 783 {
 784         return 1;
 785 }
 786
 787 static inline int ftrace_graph_notrace_addr(unsigned long addr)
 788 {
 789         return 0;
 790 }
 791 #endif /* CONFIG_DYNAMIC_FTRACE */
 792 #else /* CONFIG_FUNCTION_GRAPH_TRACER */
 793 static inline enum print_line_t
 794 print_graph_function_flags(struct trace_iterator *iter, u32 flags)
 795 {
 796         return TRACE_TYPE_UNHANDLED;
 797 }
 798 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
 799
 800 extern struct list_head ftrace_pids;
 801
 802 #ifdef CONFIG_FUNCTION_TRACER
 803 extern bool ftrace_filter_param __initdata;
 804 static inline int ftrace_trace_task(struct task_struct *task)
 805 {
 806         if (list_empty(&ftrace_pids))
 807                 return 1;
 808
 809         return test_tsk_trace_trace(task);
 810 }
 811 extern int ftrace_is_dead(void);
 812 #else
 813 static inline int ftrace_trace_task(struct task_struct *task)
 814 {
 815         return 1;
 816 }
 817 static inline int ftrace_is_dead(void) { return 0; }
 818 #endif
 819
 820 int ftrace_event_is_function(struct ftrace_event_call *call);
 821
 822 /*
 823  * struct trace_parser - servers for reading the user input separated by spaces
 824  * @cont: set if the input is not complete - no final space char was found
 825  * @buffer: holds the parsed user input
 826  * @idx: user input length
 827  * @size: buffer size
 828  */
 829 struct trace_parser {
 830         bool            cont;
 831         char            *buffer;
 832         unsigned        idx;
 833         unsigned        size;
 834 };
 835
 836 static inline bool trace_parser_loaded(struct trace_parser *parser)
 837 {
 838         return (parser->idx != 0);
 839 }
 840
 841 static inline bool trace_parser_cont(struct trace_parser *parser)
 842 {
 843         return parser->cont;
 844 }
 845
 846 static inline void trace_parser_clear(struct trace_parser *parser)
 847 {
 848         parser->cont = false;
 849         parser->idx = 0;
 850 }
 851
 852 extern int trace_parser_get_init(struct trace_parser *parser, int size);
 853 extern void trace_parser_put(struct trace_parser *parser);
 854 extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
 855         size_t cnt, loff_t *ppos);
 856
 857 /*
 858  * trace_iterator_flags is an enumeration that defines bit
 859  * positions into trace_flags that controls the output.
 860  *
 861  * NOTE: These bits must match the trace_options array in
 862  *       trace.c.
 863  */
 864 enum trace_iterator_flags {
 865         TRACE_ITER_PRINT_PARENT         = 0x01,
 866         TRACE_ITER_SYM_OFFSET           = 0x02,
 867         TRACE_ITER_SYM_ADDR             = 0x04,
 868         TRACE_ITER_VERBOSE              = 0x08,
 869         TRACE_ITER_RAW                  = 0x10,
 870         TRACE_ITER_HEX                  = 0x20,
 871         TRACE_ITER_BIN                  = 0x40,
 872         TRACE_ITER_BLOCK                = 0x80,
 873         TRACE_ITER_STACKTRACE           = 0x100,
 874         TRACE_ITER_PRINTK               = 0x200,
 875         TRACE_ITER_PREEMPTONLY          = 0x400,
 876         TRACE_ITER_BRANCH               = 0x800,
 877         TRACE_ITER_ANNOTATE             = 0x1000,
 878         TRACE_ITER_USERSTACKTRACE       = 0x2000,
 879         TRACE_ITER_SYM_USEROBJ          = 0x4000,
 880         TRACE_ITER_PRINTK_MSGONLY       = 0x8000,
 881         TRACE_ITER_CONTEXT_INFO         = 0x10000, /* Print pid/cpu/time */
 882         TRACE_ITER_LATENCY_FMT          = 0x20000,
 883         TRACE_ITER_SLEEP_TIME           = 0x40000,
 884         TRACE_ITER_GRAPH_TIME           = 0x80000,
 885         TRACE_ITER_RECORD_CMD           = 0x100000,
 886         TRACE_ITER_OVERWRITE            = 0x200000,
 887         TRACE_ITER_STOP_ON_FREE         = 0x400000,
 888         TRACE_ITER_IRQ_INFO             = 0x800000,
 889         TRACE_ITER_MARKERS              = 0x1000000,
 890         TRACE_ITER_FUNCTION             = 0x2000000,
 891 };
 892
 893 /*
 894  * TRACE_ITER_SYM_MASK masks the options in trace_flags that
 895  * control the output of kernel symbols.
 896  */
 897 #define TRACE_ITER_SYM_MASK \
 898         (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
 899
 900 extern struct tracer nop_trace;
 901
 902 #ifdef CONFIG_BRANCH_TRACER
 903 extern int enable_branch_tracing(struct trace_array *tr);
 904 extern void disable_branch_tracing(void);
 905 static inline int trace_branch_enable(struct trace_array *tr)
 906 {
 907         if (trace_flags & TRACE_ITER_BRANCH)
 908                 return enable_branch_tracing(tr);
 909         return 0;
 910 }
 911 static inline void trace_branch_disable(void)
 912 {
 913         /* due to races, always disable */
 914         disable_branch_tracing();
 915 }
 916 #else
 917 static inline int trace_branch_enable(struct trace_array *tr)
 918 {
 919         return 0;
 920 }
 921 static inline void trace_branch_disable(void)
 922 {
 923 }
 924 #endif /* CONFIG_BRANCH_TRACER */
 925
 926 /* set ring buffers to default size if not already done so */
 927 int tracing_update_buffers(void);
 928
 929 struct ftrace_event_field {
 930         struct list_head        link;
 931         const char              *name;
 932         const char              *type;
 933         int                     filter_type;
 934         int                     offset;
 935         int                     size;
 936         int                     is_signed;
 937 };
 938
 939 struct event_filter {
 940         int                     n_preds;        /* Number assigned */
 941         int                     a_preds;        /* allocated */
 942         struct filter_pred      *preds;
 943         struct filter_pred      *root;
 944         char                    *filter_string;
 945 };
 946
 947 struct event_subsystem {
 948         struct list_head        list;
 949         const char              *name;
 950         struct event_filter     *filter;
 951         int                     ref_count;
 952 };
 953
 954 struct ftrace_subsystem_dir {
 955         struct list_head                list;
 956         struct event_subsystem          *subsystem;
 957         struct trace_array              *tr;
 958         struct dentry                   *entry;
 959         int                             ref_count;
 960         int                             nr_events;
 961 };
 962
 963 #define FILTER_PRED_INVALID     ((unsigned short)-1)
 964 #define FILTER_PRED_IS_RIGHT    (1 << 15)
 965 #define FILTER_PRED_FOLD        (1 << 15)
 966
 967 /*
 968  * The max preds is the size of unsigned short with
 969  * two flags at the MSBs. One bit is used for both the IS_RIGHT
 970  * and FOLD flags. The other is reserved.
 971  *
 972  * 2^14 preds is way more than enough.
 973  */
 974 #define MAX_FILTER_PRED         16384
 975
 976 struct filter_pred;
 977 struct regex;
 978
 979 typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event);
 980
 981 typedef int (*regex_match_func)(char *str, struct regex *r, int len);
 982
 983 enum regex_type {
 984         MATCH_FULL = 0,
 985         MATCH_FRONT_ONLY,
 986         MATCH_MIDDLE_ONLY,
 987         MATCH_END_ONLY,
 988 };
 989
 990 struct regex {
 991         char                    pattern[MAX_FILTER_STR_VAL];
 992         int                     len;
 993         int                     field_len;
 994         regex_match_func        match;
 995 };
 996
 997 struct filter_pred {
 998         filter_pred_fn_t        fn;
 999         u64                     val;
1000         struct regex            regex;
1001         unsigned short          *ops;
1002         struct ftrace_event_field *field;
1003         int                     offset;
1004         int                     not;
1005         int                     op;
1006         unsigned short          index;
1007         unsigned short          parent;
1008         unsigned short          left;
1009         unsigned short          right;
1010 };
1011
1012 extern enum regex_type
1013 filter_parse_regex(char *buff, int len, char **search, int *not);
1014 extern void print_event_filter(struct ftrace_event_file *file,
1015                                struct trace_seq *s);
1016 extern int apply_event_filter(struct ftrace_event_file *file,
1017                               char *filter_string);
1018 extern int apply_subsystem_event_filter(struct ftrace_subsystem_dir *dir,
1019                                         char *filter_string);
1020 extern void print_subsystem_event_filter(struct event_subsystem *system,
1021                                          struct trace_seq *s);
1022 extern int filter_assign_type(const char *type);
1023
1024 struct ftrace_event_field *
1025 trace_find_event_field(struct ftrace_event_call *call, char *name);
1026
1027 extern void trace_event_enable_cmd_record(bool enable);
1028 extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr);
1029 extern int event_trace_del_tracer(struct trace_array *tr);
1030
1031 extern struct mutex event_mutex;
1032 extern struct list_head ftrace_events;
1033
1034 extern const char *__start___trace_bprintk_fmt[];
1035 extern const char *__stop___trace_bprintk_fmt[];
1036
1037 extern const char *__start___tracepoint_str[];
1038 extern const char *__stop___tracepoint_str[];
1039
1040 void trace_printk_init_buffers(void);
1041 void trace_printk_start_comm(void);
1042 int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set);
1043 int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled);
1044
1045 /*
1046  * Normal trace_printk() and friends allocates special buffers
1047  * to do the manipulation, as well as saves the print formats
1048  * into sections to display. But the trace infrastructure wants
1049  * to use these without the added overhead at the price of being
1050  * a bit slower (used mainly for warnings, where we don't care
1051  * about performance). The internal_trace_puts() is for such
1052  * a purpose.
1053  */
1054 #define internal_trace_puts(str) __trace_puts(_THIS_IP_, str, strlen(str))
1055
1056 #undef FTRACE_ENTRY
1057 #define FTRACE_ENTRY(call, struct_name, id, tstruct, print, filter)     \
1058         extern struct ftrace_event_call                                 \
1059         __attribute__((__aligned__(4))) event_##call;
1060 #undef FTRACE_ENTRY_DUP
1061 #define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print, filter) \
1062         FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print), \
1063                      filter)
1064 #include "trace_entries.h"
1065
1066 #if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER)
1067 int perf_ftrace_event_register(struct ftrace_event_call *call,
1068                                enum trace_reg type, void *data);
1069 #else
1070 #define perf_ftrace_event_register NULL
1071 #endif
1072
1073 #endif /* _LINUX_KERNEL_TRACE_H */