linux/kernel/trace/trace.h
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   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
  16enum trace_type {
  17        __TRACE_FIRST_TYPE = 0,
  18
  19        TRACE_FN,
  20        TRACE_CTX,
  21        TRACE_WAKE,
  22        TRACE_STACK,
  23        TRACE_PRINT,
  24        TRACE_BPRINT,
  25        TRACE_MMIO_RW,
  26        TRACE_MMIO_MAP,
  27        TRACE_BRANCH,
  28        TRACE_GRAPH_RET,
  29        TRACE_GRAPH_ENT,
  30        TRACE_USER_STACK,
  31        TRACE_BLK,
  32
  33        __TRACE_LAST_TYPE,
  34};
  35
  36
  37#undef __field
  38#define __field(type, item)             type    item;
  39
  40#undef __field_struct
  41#define __field_struct(type, item)      __field(type, item)
  42
  43#undef __field_desc
  44#define __field_desc(type, container, item)
  45
  46#undef __array
  47#define __array(type, item, size)       type    item[size];
  48
  49#undef __array_desc
  50#define __array_desc(type, container, item, size)
  51
  52#undef __dynamic_array
  53#define __dynamic_array(type, item)     type    item[];
  54
  55#undef F_STRUCT
  56#define F_STRUCT(args...)               args
  57
  58#undef FTRACE_ENTRY
  59#define FTRACE_ENTRY(name, struct_name, id, tstruct, print)     \
  60        struct struct_name {                                    \
  61                struct trace_entry      ent;                    \
  62                tstruct                                         \
  63        }
  64
  65#undef TP_ARGS
  66#define TP_ARGS(args...)        args
  67
  68#undef FTRACE_ENTRY_DUP
  69#define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk)
  70
  71#include "trace_entries.h"
  72
  73/*
  74 * syscalls are special, and need special handling, this is why
  75 * they are not included in trace_entries.h
  76 */
  77struct syscall_trace_enter {
  78        struct trace_entry      ent;
  79        int                     nr;
  80        unsigned long           args[];
  81};
  82
  83struct syscall_trace_exit {
  84        struct trace_entry      ent;
  85        int                     nr;
  86        long                    ret;
  87};
  88
  89struct kprobe_trace_entry_head {
  90        struct trace_entry      ent;
  91        unsigned long           ip;
  92};
  93
  94struct kretprobe_trace_entry_head {
  95        struct trace_entry      ent;
  96        unsigned long           func;
  97        unsigned long           ret_ip;
  98};
  99
 100/*
 101 * trace_flag_type is an enumeration that holds different
 102 * states when a trace occurs. These are:
 103 *  IRQS_OFF            - interrupts were disabled
 104 *  IRQS_NOSUPPORT      - arch does not support irqs_disabled_flags
 105 *  NEED_RESCHED        - reschedule is requested
 106 *  HARDIRQ             - inside an interrupt handler
 107 *  SOFTIRQ             - inside a softirq handler
 108 */
 109enum trace_flag_type {
 110        TRACE_FLAG_IRQS_OFF             = 0x01,
 111        TRACE_FLAG_IRQS_NOSUPPORT       = 0x02,
 112        TRACE_FLAG_NEED_RESCHED         = 0x04,
 113        TRACE_FLAG_HARDIRQ              = 0x08,
 114        TRACE_FLAG_SOFTIRQ              = 0x10,
 115};
 116
 117#define TRACE_BUF_SIZE          1024
 118
 119/*
 120 * The CPU trace array - it consists of thousands of trace entries
 121 * plus some other descriptor data: (for example which task started
 122 * the trace, etc.)
 123 */
 124struct trace_array_cpu {
 125        atomic_t                disabled;
 126        void                    *buffer_page;   /* ring buffer spare */
 127
 128        unsigned long           saved_latency;
 129        unsigned long           critical_start;
 130        unsigned long           critical_end;
 131        unsigned long           critical_sequence;
 132        unsigned long           nice;
 133        unsigned long           policy;
 134        unsigned long           rt_priority;
 135        unsigned long           skipped_entries;
 136        cycle_t                 preempt_timestamp;
 137        pid_t                   pid;
 138        uid_t                   uid;
 139        char                    comm[TASK_COMM_LEN];
 140};
 141
 142/*
 143 * The trace array - an array of per-CPU trace arrays. This is the
 144 * highest level data structure that individual tracers deal with.
 145 * They have on/off state as well:
 146 */
 147struct trace_array {
 148        struct ring_buffer      *buffer;
 149        unsigned long           entries;
 150        int                     cpu;
 151        cycle_t                 time_start;
 152        struct task_struct      *waiter;
 153        struct trace_array_cpu  *data[NR_CPUS];
 154};
 155
 156#define FTRACE_CMP_TYPE(var, type) \
 157        __builtin_types_compatible_p(typeof(var), type *)
 158
 159#undef IF_ASSIGN
 160#define IF_ASSIGN(var, entry, etype, id)                \
 161        if (FTRACE_CMP_TYPE(var, etype)) {              \
 162                var = (typeof(var))(entry);             \
 163                WARN_ON(id && (entry)->type != id);     \
 164                break;                                  \
 165        }
 166
 167/* Will cause compile errors if type is not found. */
 168extern void __ftrace_bad_type(void);
 169
 170/*
 171 * The trace_assign_type is a verifier that the entry type is
 172 * the same as the type being assigned. To add new types simply
 173 * add a line with the following format:
 174 *
 175 * IF_ASSIGN(var, ent, type, id);
 176 *
 177 *  Where "type" is the trace type that includes the trace_entry
 178 *  as the "ent" item. And "id" is the trace identifier that is
 179 *  used in the trace_type enum.
 180 *
 181 *  If the type can have more than one id, then use zero.
 182 */
 183#define trace_assign_type(var, ent)                                     \
 184        do {                                                            \
 185                IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN);     \
 186                IF_ASSIGN(var, ent, struct ctx_switch_entry, 0);        \
 187                IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK);   \
 188                IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
 189                IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT);   \
 190                IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT); \
 191                IF_ASSIGN(var, ent, struct trace_mmiotrace_rw,          \
 192                          TRACE_MMIO_RW);                               \
 193                IF_ASSIGN(var, ent, struct trace_mmiotrace_map,         \
 194                          TRACE_MMIO_MAP);                              \
 195                IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
 196                IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry,      \
 197                          TRACE_GRAPH_ENT);             \
 198                IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry,      \
 199                          TRACE_GRAPH_RET);             \
 200                __ftrace_bad_type();                                    \
 201        } while (0)
 202
 203/*
 204 * An option specific to a tracer. This is a boolean value.
 205 * The bit is the bit index that sets its value on the
 206 * flags value in struct tracer_flags.
 207 */
 208struct tracer_opt {
 209        const char      *name; /* Will appear on the trace_options file */
 210        u32             bit; /* Mask assigned in val field in tracer_flags */
 211};
 212
 213/*
 214 * The set of specific options for a tracer. Your tracer
 215 * have to set the initial value of the flags val.
 216 */
 217struct tracer_flags {
 218        u32                     val;
 219        struct tracer_opt       *opts;
 220};
 221
 222/* Makes more easy to define a tracer opt */
 223#define TRACER_OPT(s, b)        .name = #s, .bit = b
 224
 225
 226/**
 227 * struct tracer - a specific tracer and its callbacks to interact with debugfs
 228 * @name: the name chosen to select it on the available_tracers file
 229 * @init: called when one switches to this tracer (echo name > current_tracer)
 230 * @reset: called when one switches to another tracer
 231 * @start: called when tracing is unpaused (echo 1 > tracing_enabled)
 232 * @stop: called when tracing is paused (echo 0 > tracing_enabled)
 233 * @open: called when the trace file is opened
 234 * @pipe_open: called when the trace_pipe file is opened
 235 * @wait_pipe: override how the user waits for traces on trace_pipe
 236 * @close: called when the trace file is released
 237 * @pipe_close: called when the trace_pipe file is released
 238 * @read: override the default read callback on trace_pipe
 239 * @splice_read: override the default splice_read callback on trace_pipe
 240 * @selftest: selftest to run on boot (see trace_selftest.c)
 241 * @print_headers: override the first lines that describe your columns
 242 * @print_line: callback that prints a trace
 243 * @set_flag: signals one of your private flags changed (trace_options file)
 244 * @flags: your private flags
 245 */
 246struct tracer {
 247        const char              *name;
 248        int                     (*init)(struct trace_array *tr);
 249        void                    (*reset)(struct trace_array *tr);
 250        void                    (*start)(struct trace_array *tr);
 251        void                    (*stop)(struct trace_array *tr);
 252        void                    (*open)(struct trace_iterator *iter);
 253        void                    (*pipe_open)(struct trace_iterator *iter);
 254        void                    (*wait_pipe)(struct trace_iterator *iter);
 255        void                    (*close)(struct trace_iterator *iter);
 256        void                    (*pipe_close)(struct trace_iterator *iter);
 257        ssize_t                 (*read)(struct trace_iterator *iter,
 258                                        struct file *filp, char __user *ubuf,
 259                                        size_t cnt, loff_t *ppos);
 260        ssize_t                 (*splice_read)(struct trace_iterator *iter,
 261                                               struct file *filp,
 262                                               loff_t *ppos,
 263                                               struct pipe_inode_info *pipe,
 264                                               size_t len,
 265                                               unsigned int flags);
 266#ifdef CONFIG_FTRACE_STARTUP_TEST
 267        int                     (*selftest)(struct tracer *trace,
 268                                            struct trace_array *tr);
 269#endif
 270        void                    (*print_header)(struct seq_file *m);
 271        enum print_line_t       (*print_line)(struct trace_iterator *iter);
 272        /* If you handled the flag setting, return 0 */
 273        int                     (*set_flag)(u32 old_flags, u32 bit, int set);
 274        struct tracer           *next;
 275        struct tracer_flags     *flags;
 276        int                     print_max;
 277        int                     use_max_tr;
 278};
 279
 280
 281/* Only current can touch trace_recursion */
 282#define trace_recursion_inc() do { (current)->trace_recursion++; } while (0)
 283#define trace_recursion_dec() do { (current)->trace_recursion--; } while (0)
 284
 285/* Ring buffer has the 10 LSB bits to count */
 286#define trace_recursion_buffer() ((current)->trace_recursion & 0x3ff)
 287
 288/* for function tracing recursion */
 289#define TRACE_INTERNAL_BIT              (1<<11)
 290#define TRACE_GLOBAL_BIT                (1<<12)
 291/*
 292 * Abuse of the trace_recursion.
 293 * As we need a way to maintain state if we are tracing the function
 294 * graph in irq because we want to trace a particular function that
 295 * was called in irq context but we have irq tracing off. Since this
 296 * can only be modified by current, we can reuse trace_recursion.
 297 */
 298#define TRACE_IRQ_BIT                   (1<<13)
 299
 300#define trace_recursion_set(bit)        do { (current)->trace_recursion |= (bit); } while (0)
 301#define trace_recursion_clear(bit)      do { (current)->trace_recursion &= ~(bit); } while (0)
 302#define trace_recursion_test(bit)       ((current)->trace_recursion & (bit))
 303
 304#define TRACE_PIPE_ALL_CPU      -1
 305
 306int tracer_init(struct tracer *t, struct trace_array *tr);
 307int tracing_is_enabled(void);
 308void trace_wake_up(void);
 309void tracing_reset(struct trace_array *tr, int cpu);
 310void tracing_reset_online_cpus(struct trace_array *tr);
 311void tracing_reset_current(int cpu);
 312void tracing_reset_current_online_cpus(void);
 313int tracing_open_generic(struct inode *inode, struct file *filp);
 314struct dentry *trace_create_file(const char *name,
 315                                 umode_t mode,
 316                                 struct dentry *parent,
 317                                 void *data,
 318                                 const struct file_operations *fops);
 319
 320struct dentry *tracing_init_dentry(void);
 321
 322struct ring_buffer_event;
 323
 324struct ring_buffer_event *
 325trace_buffer_lock_reserve(struct ring_buffer *buffer,
 326                          int type,
 327                          unsigned long len,
 328                          unsigned long flags,
 329                          int pc);
 330void trace_buffer_unlock_commit(struct ring_buffer *buffer,
 331                                struct ring_buffer_event *event,
 332                                unsigned long flags, int pc);
 333
 334struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
 335                                                struct trace_array_cpu *data);
 336
 337struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
 338                                          int *ent_cpu, u64 *ent_ts);
 339
 340int trace_empty(struct trace_iterator *iter);
 341
 342void *trace_find_next_entry_inc(struct trace_iterator *iter);
 343
 344void trace_init_global_iter(struct trace_iterator *iter);
 345
 346void tracing_iter_reset(struct trace_iterator *iter, int cpu);
 347
 348void default_wait_pipe(struct trace_iterator *iter);
 349void poll_wait_pipe(struct trace_iterator *iter);
 350
 351void ftrace(struct trace_array *tr,
 352                            struct trace_array_cpu *data,
 353                            unsigned long ip,
 354                            unsigned long parent_ip,
 355                            unsigned long flags, int pc);
 356void tracing_sched_switch_trace(struct trace_array *tr,
 357                                struct task_struct *prev,
 358                                struct task_struct *next,
 359                                unsigned long flags, int pc);
 360
 361void tracing_sched_wakeup_trace(struct trace_array *tr,
 362                                struct task_struct *wakee,
 363                                struct task_struct *cur,
 364                                unsigned long flags, int pc);
 365void trace_function(struct trace_array *tr,
 366                    unsigned long ip,
 367                    unsigned long parent_ip,
 368                    unsigned long flags, int pc);
 369void trace_graph_function(struct trace_array *tr,
 370                    unsigned long ip,
 371                    unsigned long parent_ip,
 372                    unsigned long flags, int pc);
 373void trace_latency_header(struct seq_file *m);
 374void trace_default_header(struct seq_file *m);
 375void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
 376int trace_empty(struct trace_iterator *iter);
 377
 378void trace_graph_return(struct ftrace_graph_ret *trace);
 379int trace_graph_entry(struct ftrace_graph_ent *trace);
 380void set_graph_array(struct trace_array *tr);
 381
 382void tracing_start_cmdline_record(void);
 383void tracing_stop_cmdline_record(void);
 384void tracing_sched_switch_assign_trace(struct trace_array *tr);
 385void tracing_stop_sched_switch_record(void);
 386void tracing_start_sched_switch_record(void);
 387int register_tracer(struct tracer *type);
 388void unregister_tracer(struct tracer *type);
 389int is_tracing_stopped(void);
 390enum trace_file_type {
 391        TRACE_FILE_LAT_FMT      = 1,
 392        TRACE_FILE_ANNOTATE     = 2,
 393};
 394
 395extern cpumask_var_t __read_mostly tracing_buffer_mask;
 396
 397#define for_each_tracing_cpu(cpu)       \
 398        for_each_cpu(cpu, tracing_buffer_mask)
 399
 400extern unsigned long nsecs_to_usecs(unsigned long nsecs);
 401
 402extern unsigned long tracing_thresh;
 403
 404#ifdef CONFIG_TRACER_MAX_TRACE
 405extern unsigned long tracing_max_latency;
 406
 407void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu);
 408void update_max_tr_single(struct trace_array *tr,
 409                          struct task_struct *tsk, int cpu);
 410#endif /* CONFIG_TRACER_MAX_TRACE */
 411
 412#ifdef CONFIG_STACKTRACE
 413void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags,
 414                        int skip, int pc);
 415
 416void ftrace_trace_stack_regs(struct ring_buffer *buffer, unsigned long flags,
 417                             int skip, int pc, struct pt_regs *regs);
 418
 419void ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags,
 420                            int pc);
 421
 422void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
 423                   int pc);
 424#else
 425static inline void ftrace_trace_stack(struct ring_buffer *buffer,
 426                                      unsigned long flags, int skip, int pc)
 427{
 428}
 429
 430static inline void ftrace_trace_stack_regs(struct ring_buffer *buffer,
 431                                           unsigned long flags, int skip,
 432                                           int pc, struct pt_regs *regs)
 433{
 434}
 435
 436static inline void ftrace_trace_userstack(struct ring_buffer *buffer,
 437                                          unsigned long flags, int pc)
 438{
 439}
 440
 441static inline void __trace_stack(struct trace_array *tr, unsigned long flags,
 442                                 int skip, int pc)
 443{
 444}
 445#endif /* CONFIG_STACKTRACE */
 446
 447extern cycle_t ftrace_now(int cpu);
 448
 449extern void trace_find_cmdline(int pid, char comm[]);
 450
 451#ifdef CONFIG_DYNAMIC_FTRACE
 452extern unsigned long ftrace_update_tot_cnt;
 453#define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
 454extern int DYN_FTRACE_TEST_NAME(void);
 455#define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
 456extern int DYN_FTRACE_TEST_NAME2(void);
 457#endif
 458
 459extern int ring_buffer_expanded;
 460extern bool tracing_selftest_disabled;
 461DECLARE_PER_CPU(int, ftrace_cpu_disabled);
 462
 463#ifdef CONFIG_FTRACE_STARTUP_TEST
 464extern int trace_selftest_startup_function(struct tracer *trace,
 465                                           struct trace_array *tr);
 466extern int trace_selftest_startup_function_graph(struct tracer *trace,
 467                                                 struct trace_array *tr);
 468extern int trace_selftest_startup_irqsoff(struct tracer *trace,
 469                                          struct trace_array *tr);
 470extern int trace_selftest_startup_preemptoff(struct tracer *trace,
 471                                             struct trace_array *tr);
 472extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
 473                                                 struct trace_array *tr);
 474extern int trace_selftest_startup_wakeup(struct tracer *trace,
 475                                         struct trace_array *tr);
 476extern int trace_selftest_startup_nop(struct tracer *trace,
 477                                         struct trace_array *tr);
 478extern int trace_selftest_startup_sched_switch(struct tracer *trace,
 479                                               struct trace_array *tr);
 480extern int trace_selftest_startup_branch(struct tracer *trace,
 481                                         struct trace_array *tr);
 482#endif /* CONFIG_FTRACE_STARTUP_TEST */
 483
 484extern void *head_page(struct trace_array_cpu *data);
 485extern unsigned long long ns2usecs(cycle_t nsec);
 486extern int
 487trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
 488extern int
 489trace_vprintk(unsigned long ip, const char *fmt, va_list args);
 490extern int
 491trace_array_vprintk(struct trace_array *tr,
 492                    unsigned long ip, const char *fmt, va_list args);
 493int trace_array_printk(struct trace_array *tr,
 494                       unsigned long ip, const char *fmt, ...);
 495void trace_printk_seq(struct trace_seq *s);
 496enum print_line_t print_trace_line(struct trace_iterator *iter);
 497
 498extern unsigned long trace_flags;
 499
 500extern int trace_clock_id;
 501
 502/* Standard output formatting function used for function return traces */
 503#ifdef CONFIG_FUNCTION_GRAPH_TRACER
 504
 505/* Flag options */
 506#define TRACE_GRAPH_PRINT_OVERRUN       0x1
 507#define TRACE_GRAPH_PRINT_CPU           0x2
 508#define TRACE_GRAPH_PRINT_OVERHEAD      0x4
 509#define TRACE_GRAPH_PRINT_PROC          0x8
 510#define TRACE_GRAPH_PRINT_DURATION      0x10
 511#define TRACE_GRAPH_PRINT_ABS_TIME      0x20
 512
 513extern enum print_line_t
 514print_graph_function_flags(struct trace_iterator *iter, u32 flags);
 515extern void print_graph_headers_flags(struct seq_file *s, u32 flags);
 516extern enum print_line_t
 517trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
 518extern void graph_trace_open(struct trace_iterator *iter);
 519extern void graph_trace_close(struct trace_iterator *iter);
 520extern int __trace_graph_entry(struct trace_array *tr,
 521                               struct ftrace_graph_ent *trace,
 522                               unsigned long flags, int pc);
 523extern void __trace_graph_return(struct trace_array *tr,
 524                                 struct ftrace_graph_ret *trace,
 525                                 unsigned long flags, int pc);
 526
 527
 528#ifdef CONFIG_DYNAMIC_FTRACE
 529/* TODO: make this variable */
 530#define FTRACE_GRAPH_MAX_FUNCS          32
 531extern int ftrace_graph_filter_enabled;
 532extern int ftrace_graph_count;
 533extern unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS];
 534
 535static inline int ftrace_graph_addr(unsigned long addr)
 536{
 537        int i;
 538
 539        if (!ftrace_graph_filter_enabled)
 540                return 1;
 541
 542        for (i = 0; i < ftrace_graph_count; i++) {
 543                if (addr == ftrace_graph_funcs[i]) {
 544                        /*
 545                         * If no irqs are to be traced, but a set_graph_function
 546                         * is set, and called by an interrupt handler, we still
 547                         * want to trace it.
 548                         */
 549                        if (in_irq())
 550                                trace_recursion_set(TRACE_IRQ_BIT);
 551                        else
 552                                trace_recursion_clear(TRACE_IRQ_BIT);
 553                        return 1;
 554                }
 555        }
 556
 557        return 0;
 558}
 559#else
 560static inline int ftrace_graph_addr(unsigned long addr)
 561{
 562        return 1;
 563}
 564#endif /* CONFIG_DYNAMIC_FTRACE */
 565#else /* CONFIG_FUNCTION_GRAPH_TRACER */
 566static inline enum print_line_t
 567print_graph_function_flags(struct trace_iterator *iter, u32 flags)
 568{
 569        return TRACE_TYPE_UNHANDLED;
 570}
 571#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
 572
 573extern struct list_head ftrace_pids;
 574
 575#ifdef CONFIG_FUNCTION_TRACER
 576static inline int ftrace_trace_task(struct task_struct *task)
 577{
 578        if (list_empty(&ftrace_pids))
 579                return 1;
 580
 581        return test_tsk_trace_trace(task);
 582}
 583extern int ftrace_is_dead(void);
 584#else
 585static inline int ftrace_trace_task(struct task_struct *task)
 586{
 587        return 1;
 588}
 589static inline int ftrace_is_dead(void) { return 0; }
 590#endif
 591
 592/*
 593 * struct trace_parser - servers for reading the user input separated by spaces
 594 * @cont: set if the input is not complete - no final space char was found
 595 * @buffer: holds the parsed user input
 596 * @idx: user input length
 597 * @size: buffer size
 598 */
 599struct trace_parser {
 600        bool            cont;
 601        char            *buffer;
 602        unsigned        idx;
 603        unsigned        size;
 604};
 605
 606static inline bool trace_parser_loaded(struct trace_parser *parser)
 607{
 608        return (parser->idx != 0);
 609}
 610
 611static inline bool trace_parser_cont(struct trace_parser *parser)
 612{
 613        return parser->cont;
 614}
 615
 616static inline void trace_parser_clear(struct trace_parser *parser)
 617{
 618        parser->cont = false;
 619        parser->idx = 0;
 620}
 621
 622extern int trace_parser_get_init(struct trace_parser *parser, int size);
 623extern void trace_parser_put(struct trace_parser *parser);
 624extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
 625        size_t cnt, loff_t *ppos);
 626
 627/*
 628 * trace_iterator_flags is an enumeration that defines bit
 629 * positions into trace_flags that controls the output.
 630 *
 631 * NOTE: These bits must match the trace_options array in
 632 *       trace.c.
 633 */
 634enum trace_iterator_flags {
 635        TRACE_ITER_PRINT_PARENT         = 0x01,
 636        TRACE_ITER_SYM_OFFSET           = 0x02,
 637        TRACE_ITER_SYM_ADDR             = 0x04,
 638        TRACE_ITER_VERBOSE              = 0x08,
 639        TRACE_ITER_RAW                  = 0x10,
 640        TRACE_ITER_HEX                  = 0x20,
 641        TRACE_ITER_BIN                  = 0x40,
 642        TRACE_ITER_BLOCK                = 0x80,
 643        TRACE_ITER_STACKTRACE           = 0x100,
 644        TRACE_ITER_PRINTK               = 0x200,
 645        TRACE_ITER_PREEMPTONLY          = 0x400,
 646        TRACE_ITER_BRANCH               = 0x800,
 647        TRACE_ITER_ANNOTATE             = 0x1000,
 648        TRACE_ITER_USERSTACKTRACE       = 0x2000,
 649        TRACE_ITER_SYM_USEROBJ          = 0x4000,
 650        TRACE_ITER_PRINTK_MSGONLY       = 0x8000,
 651        TRACE_ITER_CONTEXT_INFO         = 0x10000, /* Print pid/cpu/time */
 652        TRACE_ITER_LATENCY_FMT          = 0x20000,
 653        TRACE_ITER_SLEEP_TIME           = 0x40000,
 654        TRACE_ITER_GRAPH_TIME           = 0x80000,
 655        TRACE_ITER_RECORD_CMD           = 0x100000,
 656        TRACE_ITER_OVERWRITE            = 0x200000,
 657        TRACE_ITER_STOP_ON_FREE         = 0x400000,
 658        TRACE_ITER_IRQ_INFO             = 0x800000,
 659};
 660
 661/*
 662 * TRACE_ITER_SYM_MASK masks the options in trace_flags that
 663 * control the output of kernel symbols.
 664 */
 665#define TRACE_ITER_SYM_MASK \
 666        (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
 667
 668extern struct tracer nop_trace;
 669
 670#ifdef CONFIG_BRANCH_TRACER
 671extern int enable_branch_tracing(struct trace_array *tr);
 672extern void disable_branch_tracing(void);
 673static inline int trace_branch_enable(struct trace_array *tr)
 674{
 675        if (trace_flags & TRACE_ITER_BRANCH)
 676                return enable_branch_tracing(tr);
 677        return 0;
 678}
 679static inline void trace_branch_disable(void)
 680{
 681        /* due to races, always disable */
 682        disable_branch_tracing();
 683}
 684#else
 685static inline int trace_branch_enable(struct trace_array *tr)
 686{
 687        return 0;
 688}
 689static inline void trace_branch_disable(void)
 690{
 691}
 692#endif /* CONFIG_BRANCH_TRACER */
 693
 694/* set ring buffers to default size if not already done so */
 695int tracing_update_buffers(void);
 696
 697/* trace event type bit fields, not numeric */
 698enum {
 699        TRACE_EVENT_TYPE_PRINTF         = 1,
 700        TRACE_EVENT_TYPE_RAW            = 2,
 701};
 702
 703struct ftrace_event_field {
 704        struct list_head        link;
 705        char                    *name;
 706        char                    *type;
 707        int                     filter_type;
 708        int                     offset;
 709        int                     size;
 710        int                     is_signed;
 711};
 712
 713struct event_filter {
 714        int                     n_preds;        /* Number assigned */
 715        int                     a_preds;        /* allocated */
 716        struct filter_pred      *preds;
 717        struct filter_pred      *root;
 718        char                    *filter_string;
 719};
 720
 721struct event_subsystem {
 722        struct list_head        list;
 723        const char              *name;
 724        struct dentry           *entry;
 725        struct event_filter     *filter;
 726        int                     nr_events;
 727        int                     ref_count;
 728};
 729
 730#define FILTER_PRED_INVALID     ((unsigned short)-1)
 731#define FILTER_PRED_IS_RIGHT    (1 << 15)
 732#define FILTER_PRED_FOLD        (1 << 15)
 733
 734/*
 735 * The max preds is the size of unsigned short with
 736 * two flags at the MSBs. One bit is used for both the IS_RIGHT
 737 * and FOLD flags. The other is reserved.
 738 *
 739 * 2^14 preds is way more than enough.
 740 */
 741#define MAX_FILTER_PRED         16384
 742
 743struct filter_pred;
 744struct regex;
 745
 746typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event);
 747
 748typedef int (*regex_match_func)(char *str, struct regex *r, int len);
 749
 750enum regex_type {
 751        MATCH_FULL = 0,
 752        MATCH_FRONT_ONLY,
 753        MATCH_MIDDLE_ONLY,
 754        MATCH_END_ONLY,
 755};
 756
 757struct regex {
 758        char                    pattern[MAX_FILTER_STR_VAL];
 759        int                     len;
 760        int                     field_len;
 761        regex_match_func        match;
 762};
 763
 764struct filter_pred {
 765        filter_pred_fn_t        fn;
 766        u64                     val;
 767        struct regex            regex;
 768        unsigned short          *ops;
 769#ifdef CONFIG_FTRACE_STARTUP_TEST
 770        struct ftrace_event_field *field;
 771#endif
 772        int                     offset;
 773        int                     not;
 774        int                     op;
 775        unsigned short          index;
 776        unsigned short          parent;
 777        unsigned short          left;
 778        unsigned short          right;
 779};
 780
 781extern struct list_head ftrace_common_fields;
 782
 783extern enum regex_type
 784filter_parse_regex(char *buff, int len, char **search, int *not);
 785extern void print_event_filter(struct ftrace_event_call *call,
 786                               struct trace_seq *s);
 787extern int apply_event_filter(struct ftrace_event_call *call,
 788                              char *filter_string);
 789extern int apply_subsystem_event_filter(struct event_subsystem *system,
 790                                        char *filter_string);
 791extern void print_subsystem_event_filter(struct event_subsystem *system,
 792                                         struct trace_seq *s);
 793extern int filter_assign_type(const char *type);
 794
 795struct list_head *
 796trace_get_fields(struct ftrace_event_call *event_call);
 797
 798static inline int
 799filter_check_discard(struct ftrace_event_call *call, void *rec,
 800                     struct ring_buffer *buffer,
 801                     struct ring_buffer_event *event)
 802{
 803        if (unlikely(call->flags & TRACE_EVENT_FL_FILTERED) &&
 804            !filter_match_preds(call->filter, rec)) {
 805                ring_buffer_discard_commit(buffer, event);
 806                return 1;
 807        }
 808
 809        return 0;
 810}
 811
 812extern void trace_event_enable_cmd_record(bool enable);
 813
 814extern struct mutex event_mutex;
 815extern struct list_head ftrace_events;
 816
 817extern const char *__start___trace_bprintk_fmt[];
 818extern const char *__stop___trace_bprintk_fmt[];
 819
 820#undef FTRACE_ENTRY
 821#define FTRACE_ENTRY(call, struct_name, id, tstruct, print)             \
 822        extern struct ftrace_event_call                                 \
 823        __attribute__((__aligned__(4))) event_##call;
 824#undef FTRACE_ENTRY_DUP
 825#define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print)         \
 826        FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
 827#include "trace_entries.h"
 828
 829#endif /* _LINUX_KERNEL_TRACE_H */
 830