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