linux/kernel/trace/trace.h
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   1// SPDX-License-Identifier: GPL-2.0
   2
   3#ifndef _LINUX_KERNEL_TRACE_H
   4#define _LINUX_KERNEL_TRACE_H
   5
   6#include <linux/fs.h>
   7#include <linux/atomic.h>
   8#include <linux/sched.h>
   9#include <linux/clocksource.h>
  10#include <linux/ring_buffer.h>
  11#include <linux/mmiotrace.h>
  12#include <linux/tracepoint.h>
  13#include <linux/ftrace.h>
  14#include <linux/trace.h>
  15#include <linux/hw_breakpoint.h>
  16#include <linux/trace_seq.h>
  17#include <linux/trace_events.h>
  18#include <linux/compiler.h>
  19#include <linux/glob.h>
  20#include <linux/irq_work.h>
  21#include <linux/workqueue.h>
  22#include <linux/ctype.h>
  23
  24#ifdef CONFIG_FTRACE_SYSCALLS
  25#include <asm/unistd.h>         /* For NR_SYSCALLS           */
  26#include <asm/syscall.h>        /* some archs define it here */
  27#endif
  28
  29enum trace_type {
  30        __TRACE_FIRST_TYPE = 0,
  31
  32        TRACE_FN,
  33        TRACE_CTX,
  34        TRACE_WAKE,
  35        TRACE_STACK,
  36        TRACE_PRINT,
  37        TRACE_BPRINT,
  38        TRACE_MMIO_RW,
  39        TRACE_MMIO_MAP,
  40        TRACE_BRANCH,
  41        TRACE_GRAPH_RET,
  42        TRACE_GRAPH_ENT,
  43        TRACE_USER_STACK,
  44        TRACE_BLK,
  45        TRACE_BPUTS,
  46        TRACE_HWLAT,
  47        TRACE_RAW_DATA,
  48        TRACE_FUNC_REPEATS,
  49
  50        __TRACE_LAST_TYPE,
  51};
  52
  53
  54#undef __field
  55#define __field(type, item)             type    item;
  56
  57#undef __field_fn
  58#define __field_fn(type, item)          type    item;
  59
  60#undef __field_struct
  61#define __field_struct(type, item)      __field(type, item)
  62
  63#undef __field_desc
  64#define __field_desc(type, container, item)
  65
  66#undef __field_packed
  67#define __field_packed(type, container, item)
  68
  69#undef __array
  70#define __array(type, item, size)       type    item[size];
  71
  72#undef __array_desc
  73#define __array_desc(type, container, item, size)
  74
  75#undef __dynamic_array
  76#define __dynamic_array(type, item)     type    item[];
  77
  78#undef F_STRUCT
  79#define F_STRUCT(args...)               args
  80
  81#undef FTRACE_ENTRY
  82#define FTRACE_ENTRY(name, struct_name, id, tstruct, print)             \
  83        struct struct_name {                                            \
  84                struct trace_entry      ent;                            \
  85                tstruct                                                 \
  86        }
  87
  88#undef FTRACE_ENTRY_DUP
  89#define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk)
  90
  91#undef FTRACE_ENTRY_REG
  92#define FTRACE_ENTRY_REG(name, struct_name, id, tstruct, print, regfn)  \
  93        FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print))
  94
  95#undef FTRACE_ENTRY_PACKED
  96#define FTRACE_ENTRY_PACKED(name, struct_name, id, tstruct, print)      \
  97        FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print)) __packed
  98
  99#include "trace_entries.h"
 100
 101/* Use this for memory failure errors */
 102#define MEM_FAIL(condition, fmt, ...) ({                        \
 103        static bool __section(".data.once") __warned;           \
 104        int __ret_warn_once = !!(condition);                    \
 105                                                                \
 106        if (unlikely(__ret_warn_once && !__warned)) {           \
 107                __warned = true;                                \
 108                pr_err("ERROR: " fmt, ##__VA_ARGS__);           \
 109        }                                                       \
 110        unlikely(__ret_warn_once);                              \
 111})
 112
 113/*
 114 * syscalls are special, and need special handling, this is why
 115 * they are not included in trace_entries.h
 116 */
 117struct syscall_trace_enter {
 118        struct trace_entry      ent;
 119        int                     nr;
 120        unsigned long           args[];
 121};
 122
 123struct syscall_trace_exit {
 124        struct trace_entry      ent;
 125        int                     nr;
 126        long                    ret;
 127};
 128
 129struct kprobe_trace_entry_head {
 130        struct trace_entry      ent;
 131        unsigned long           ip;
 132};
 133
 134struct kretprobe_trace_entry_head {
 135        struct trace_entry      ent;
 136        unsigned long           func;
 137        unsigned long           ret_ip;
 138};
 139
 140#define TRACE_BUF_SIZE          1024
 141
 142struct trace_array;
 143
 144/*
 145 * The CPU trace array - it consists of thousands of trace entries
 146 * plus some other descriptor data: (for example which task started
 147 * the trace, etc.)
 148 */
 149struct trace_array_cpu {
 150        atomic_t                disabled;
 151        void                    *buffer_page;   /* ring buffer spare */
 152
 153        unsigned long           entries;
 154        unsigned long           saved_latency;
 155        unsigned long           critical_start;
 156        unsigned long           critical_end;
 157        unsigned long           critical_sequence;
 158        unsigned long           nice;
 159        unsigned long           policy;
 160        unsigned long           rt_priority;
 161        unsigned long           skipped_entries;
 162        u64                     preempt_timestamp;
 163        pid_t                   pid;
 164        kuid_t                  uid;
 165        char                    comm[TASK_COMM_LEN];
 166
 167#ifdef CONFIG_FUNCTION_TRACER
 168        int                     ftrace_ignore_pid;
 169#endif
 170        bool                    ignore_pid;
 171};
 172
 173struct tracer;
 174struct trace_option_dentry;
 175
 176struct array_buffer {
 177        struct trace_array              *tr;
 178        struct trace_buffer             *buffer;
 179        struct trace_array_cpu __percpu *data;
 180        u64                             time_start;
 181        int                             cpu;
 182};
 183
 184#define TRACE_FLAGS_MAX_SIZE            32
 185
 186struct trace_options {
 187        struct tracer                   *tracer;
 188        struct trace_option_dentry      *topts;
 189};
 190
 191struct trace_pid_list {
 192        int                             pid_max;
 193        unsigned long                   *pids;
 194};
 195
 196enum {
 197        TRACE_PIDS              = BIT(0),
 198        TRACE_NO_PIDS           = BIT(1),
 199};
 200
 201static inline bool pid_type_enabled(int type, struct trace_pid_list *pid_list,
 202                                    struct trace_pid_list *no_pid_list)
 203{
 204        /* Return true if the pid list in type has pids */
 205        return ((type & TRACE_PIDS) && pid_list) ||
 206                ((type & TRACE_NO_PIDS) && no_pid_list);
 207}
 208
 209static inline bool still_need_pid_events(int type, struct trace_pid_list *pid_list,
 210                                         struct trace_pid_list *no_pid_list)
 211{
 212        /*
 213         * Turning off what is in @type, return true if the "other"
 214         * pid list, still has pids in it.
 215         */
 216        return (!(type & TRACE_PIDS) && pid_list) ||
 217                (!(type & TRACE_NO_PIDS) && no_pid_list);
 218}
 219
 220typedef bool (*cond_update_fn_t)(struct trace_array *tr, void *cond_data);
 221
 222/**
 223 * struct cond_snapshot - conditional snapshot data and callback
 224 *
 225 * The cond_snapshot structure encapsulates a callback function and
 226 * data associated with the snapshot for a given tracing instance.
 227 *
 228 * When a snapshot is taken conditionally, by invoking
 229 * tracing_snapshot_cond(tr, cond_data), the cond_data passed in is
 230 * passed in turn to the cond_snapshot.update() function.  That data
 231 * can be compared by the update() implementation with the cond_data
 232 * contained within the struct cond_snapshot instance associated with
 233 * the trace_array.  Because the tr->max_lock is held throughout the
 234 * update() call, the update() function can directly retrieve the
 235 * cond_snapshot and cond_data associated with the per-instance
 236 * snapshot associated with the trace_array.
 237 *
 238 * The cond_snapshot.update() implementation can save data to be
 239 * associated with the snapshot if it decides to, and returns 'true'
 240 * in that case, or it returns 'false' if the conditional snapshot
 241 * shouldn't be taken.
 242 *
 243 * The cond_snapshot instance is created and associated with the
 244 * user-defined cond_data by tracing_cond_snapshot_enable().
 245 * Likewise, the cond_snapshot instance is destroyed and is no longer
 246 * associated with the trace instance by
 247 * tracing_cond_snapshot_disable().
 248 *
 249 * The method below is required.
 250 *
 251 * @update: When a conditional snapshot is invoked, the update()
 252 *      callback function is invoked with the tr->max_lock held.  The
 253 *      update() implementation signals whether or not to actually
 254 *      take the snapshot, by returning 'true' if so, 'false' if no
 255 *      snapshot should be taken.  Because the max_lock is held for
 256 *      the duration of update(), the implementation is safe to
 257 *      directly retrieved and save any implementation data it needs
 258 *      to in association with the snapshot.
 259 */
 260struct cond_snapshot {
 261        void                            *cond_data;
 262        cond_update_fn_t                update;
 263};
 264
 265/*
 266 * struct trace_func_repeats - used to keep track of the consecutive
 267 * (on the same CPU) calls of a single function.
 268 */
 269struct trace_func_repeats {
 270        unsigned long   ip;
 271        unsigned long   parent_ip;
 272        unsigned long   count;
 273        u64             ts_last_call;
 274};
 275
 276/*
 277 * The trace array - an array of per-CPU trace arrays. This is the
 278 * highest level data structure that individual tracers deal with.
 279 * They have on/off state as well:
 280 */
 281struct trace_array {
 282        struct list_head        list;
 283        char                    *name;
 284        struct array_buffer     array_buffer;
 285#ifdef CONFIG_TRACER_MAX_TRACE
 286        /*
 287         * The max_buffer is used to snapshot the trace when a maximum
 288         * latency is reached, or when the user initiates a snapshot.
 289         * Some tracers will use this to store a maximum trace while
 290         * it continues examining live traces.
 291         *
 292         * The buffers for the max_buffer are set up the same as the array_buffer
 293         * When a snapshot is taken, the buffer of the max_buffer is swapped
 294         * with the buffer of the array_buffer and the buffers are reset for
 295         * the array_buffer so the tracing can continue.
 296         */
 297        struct array_buffer     max_buffer;
 298        bool                    allocated_snapshot;
 299#endif
 300#if defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER)
 301        unsigned long           max_latency;
 302#ifdef CONFIG_FSNOTIFY
 303        struct dentry           *d_max_latency;
 304        struct work_struct      fsnotify_work;
 305        struct irq_work         fsnotify_irqwork;
 306#endif
 307#endif
 308        struct trace_pid_list   __rcu *filtered_pids;
 309        struct trace_pid_list   __rcu *filtered_no_pids;
 310        /*
 311         * max_lock is used to protect the swapping of buffers
 312         * when taking a max snapshot. The buffers themselves are
 313         * protected by per_cpu spinlocks. But the action of the swap
 314         * needs its own lock.
 315         *
 316         * This is defined as a arch_spinlock_t in order to help
 317         * with performance when lockdep debugging is enabled.
 318         *
 319         * It is also used in other places outside the update_max_tr
 320         * so it needs to be defined outside of the
 321         * CONFIG_TRACER_MAX_TRACE.
 322         */
 323        arch_spinlock_t         max_lock;
 324        int                     buffer_disabled;
 325#ifdef CONFIG_FTRACE_SYSCALLS
 326        int                     sys_refcount_enter;
 327        int                     sys_refcount_exit;
 328        struct trace_event_file __rcu *enter_syscall_files[NR_syscalls];
 329        struct trace_event_file __rcu *exit_syscall_files[NR_syscalls];
 330#endif
 331        int                     stop_count;
 332        int                     clock_id;
 333        int                     nr_topts;
 334        bool                    clear_trace;
 335        int                     buffer_percent;
 336        unsigned int            n_err_log_entries;
 337        struct tracer           *current_trace;
 338        unsigned int            trace_flags;
 339        unsigned char           trace_flags_index[TRACE_FLAGS_MAX_SIZE];
 340        unsigned int            flags;
 341        raw_spinlock_t          start_lock;
 342        struct list_head        err_log;
 343        struct dentry           *dir;
 344        struct dentry           *options;
 345        struct dentry           *percpu_dir;
 346        struct dentry           *event_dir;
 347        struct trace_options    *topts;
 348        struct list_head        systems;
 349        struct list_head        events;
 350        struct trace_event_file *trace_marker_file;
 351        cpumask_var_t           tracing_cpumask; /* only trace on set CPUs */
 352        int                     ref;
 353        int                     trace_ref;
 354#ifdef CONFIG_FUNCTION_TRACER
 355        struct ftrace_ops       *ops;
 356        struct trace_pid_list   __rcu *function_pids;
 357        struct trace_pid_list   __rcu *function_no_pids;
 358#ifdef CONFIG_DYNAMIC_FTRACE
 359        /* All of these are protected by the ftrace_lock */
 360        struct list_head        func_probes;
 361        struct list_head        mod_trace;
 362        struct list_head        mod_notrace;
 363#endif
 364        /* function tracing enabled */
 365        int                     function_enabled;
 366#endif
 367        int                     no_filter_buffering_ref;
 368        struct list_head        hist_vars;
 369#ifdef CONFIG_TRACER_SNAPSHOT
 370        struct cond_snapshot    *cond_snapshot;
 371#endif
 372        struct trace_func_repeats       __percpu *last_func_repeats;
 373};
 374
 375enum {
 376        TRACE_ARRAY_FL_GLOBAL   = (1 << 0)
 377};
 378
 379extern struct list_head ftrace_trace_arrays;
 380
 381extern struct mutex trace_types_lock;
 382
 383extern int trace_array_get(struct trace_array *tr);
 384extern int tracing_check_open_get_tr(struct trace_array *tr);
 385extern struct trace_array *trace_array_find(const char *instance);
 386extern struct trace_array *trace_array_find_get(const char *instance);
 387
 388extern u64 tracing_event_time_stamp(struct trace_buffer *buffer, struct ring_buffer_event *rbe);
 389extern int tracing_set_filter_buffering(struct trace_array *tr, bool set);
 390extern int tracing_set_clock(struct trace_array *tr, const char *clockstr);
 391
 392extern bool trace_clock_in_ns(struct trace_array *tr);
 393
 394/*
 395 * The global tracer (top) should be the first trace array added,
 396 * but we check the flag anyway.
 397 */
 398static inline struct trace_array *top_trace_array(void)
 399{
 400        struct trace_array *tr;
 401
 402        if (list_empty(&ftrace_trace_arrays))
 403                return NULL;
 404
 405        tr = list_entry(ftrace_trace_arrays.prev,
 406                        typeof(*tr), list);
 407        WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL));
 408        return tr;
 409}
 410
 411#define FTRACE_CMP_TYPE(var, type) \
 412        __builtin_types_compatible_p(typeof(var), type *)
 413
 414#undef IF_ASSIGN
 415#define IF_ASSIGN(var, entry, etype, id)                        \
 416        if (FTRACE_CMP_TYPE(var, etype)) {                      \
 417                var = (typeof(var))(entry);                     \
 418                WARN_ON(id != 0 && (entry)->type != id);        \
 419                break;                                          \
 420        }
 421
 422/* Will cause compile errors if type is not found. */
 423extern void __ftrace_bad_type(void);
 424
 425/*
 426 * The trace_assign_type is a verifier that the entry type is
 427 * the same as the type being assigned. To add new types simply
 428 * add a line with the following format:
 429 *
 430 * IF_ASSIGN(var, ent, type, id);
 431 *
 432 *  Where "type" is the trace type that includes the trace_entry
 433 *  as the "ent" item. And "id" is the trace identifier that is
 434 *  used in the trace_type enum.
 435 *
 436 *  If the type can have more than one id, then use zero.
 437 */
 438#define trace_assign_type(var, ent)                                     \
 439        do {                                                            \
 440                IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN);     \
 441                IF_ASSIGN(var, ent, struct ctx_switch_entry, 0);        \
 442                IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK);   \
 443                IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
 444                IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT);   \
 445                IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT); \
 446                IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS);   \
 447                IF_ASSIGN(var, ent, struct hwlat_entry, TRACE_HWLAT);   \
 448                IF_ASSIGN(var, ent, struct raw_data_entry, TRACE_RAW_DATA);\
 449                IF_ASSIGN(var, ent, struct trace_mmiotrace_rw,          \
 450                          TRACE_MMIO_RW);                               \
 451                IF_ASSIGN(var, ent, struct trace_mmiotrace_map,         \
 452                          TRACE_MMIO_MAP);                              \
 453                IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
 454                IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry,      \
 455                          TRACE_GRAPH_ENT);             \
 456                IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry,      \
 457                          TRACE_GRAPH_RET);             \
 458                IF_ASSIGN(var, ent, struct func_repeats_entry,          \
 459                          TRACE_FUNC_REPEATS);                          \
 460                __ftrace_bad_type();                                    \
 461        } while (0)
 462
 463/*
 464 * An option specific to a tracer. This is a boolean value.
 465 * The bit is the bit index that sets its value on the
 466 * flags value in struct tracer_flags.
 467 */
 468struct tracer_opt {
 469        const char      *name; /* Will appear on the trace_options file */
 470        u32             bit; /* Mask assigned in val field in tracer_flags */
 471};
 472
 473/*
 474 * The set of specific options for a tracer. Your tracer
 475 * have to set the initial value of the flags val.
 476 */
 477struct tracer_flags {
 478        u32                     val;
 479        struct tracer_opt       *opts;
 480        struct tracer           *trace;
 481};
 482
 483/* Makes more easy to define a tracer opt */
 484#define TRACER_OPT(s, b)        .name = #s, .bit = b
 485
 486
 487struct trace_option_dentry {
 488        struct tracer_opt               *opt;
 489        struct tracer_flags             *flags;
 490        struct trace_array              *tr;
 491        struct dentry                   *entry;
 492};
 493
 494/**
 495 * struct tracer - a specific tracer and its callbacks to interact with tracefs
 496 * @name: the name chosen to select it on the available_tracers file
 497 * @init: called when one switches to this tracer (echo name > current_tracer)
 498 * @reset: called when one switches to another tracer
 499 * @start: called when tracing is unpaused (echo 1 > tracing_on)
 500 * @stop: called when tracing is paused (echo 0 > tracing_on)
 501 * @update_thresh: called when tracing_thresh is updated
 502 * @open: called when the trace file is opened
 503 * @pipe_open: called when the trace_pipe file is opened
 504 * @close: called when the trace file is released
 505 * @pipe_close: called when the trace_pipe file is released
 506 * @read: override the default read callback on trace_pipe
 507 * @splice_read: override the default splice_read callback on trace_pipe
 508 * @selftest: selftest to run on boot (see trace_selftest.c)
 509 * @print_headers: override the first lines that describe your columns
 510 * @print_line: callback that prints a trace
 511 * @set_flag: signals one of your private flags changed (trace_options file)
 512 * @flags: your private flags
 513 */
 514struct tracer {
 515        const char              *name;
 516        int                     (*init)(struct trace_array *tr);
 517        void                    (*reset)(struct trace_array *tr);
 518        void                    (*start)(struct trace_array *tr);
 519        void                    (*stop)(struct trace_array *tr);
 520        int                     (*update_thresh)(struct trace_array *tr);
 521        void                    (*open)(struct trace_iterator *iter);
 522        void                    (*pipe_open)(struct trace_iterator *iter);
 523        void                    (*close)(struct trace_iterator *iter);
 524        void                    (*pipe_close)(struct trace_iterator *iter);
 525        ssize_t                 (*read)(struct trace_iterator *iter,
 526                                        struct file *filp, char __user *ubuf,
 527                                        size_t cnt, loff_t *ppos);
 528        ssize_t                 (*splice_read)(struct trace_iterator *iter,
 529                                               struct file *filp,
 530                                               loff_t *ppos,
 531                                               struct pipe_inode_info *pipe,
 532                                               size_t len,
 533                                               unsigned int flags);
 534#ifdef CONFIG_FTRACE_STARTUP_TEST
 535        int                     (*selftest)(struct tracer *trace,
 536                                            struct trace_array *tr);
 537#endif
 538        void                    (*print_header)(struct seq_file *m);
 539        enum print_line_t       (*print_line)(struct trace_iterator *iter);
 540        /* If you handled the flag setting, return 0 */
 541        int                     (*set_flag)(struct trace_array *tr,
 542                                            u32 old_flags, u32 bit, int set);
 543        /* Return 0 if OK with change, else return non-zero */
 544        int                     (*flag_changed)(struct trace_array *tr,
 545                                                u32 mask, int set);
 546        struct tracer           *next;
 547        struct tracer_flags     *flags;
 548        int                     enabled;
 549        bool                    print_max;
 550        bool                    allow_instances;
 551#ifdef CONFIG_TRACER_MAX_TRACE
 552        bool                    use_max_tr;
 553#endif
 554        /* True if tracer cannot be enabled in kernel param */
 555        bool                    noboot;
 556};
 557
 558static inline struct ring_buffer_iter *
 559trace_buffer_iter(struct trace_iterator *iter, int cpu)
 560{
 561        return iter->buffer_iter ? iter->buffer_iter[cpu] : NULL;
 562}
 563
 564int tracer_init(struct tracer *t, struct trace_array *tr);
 565int tracing_is_enabled(void);
 566void tracing_reset_online_cpus(struct array_buffer *buf);
 567void tracing_reset_current(int cpu);
 568void tracing_reset_all_online_cpus(void);
 569int tracing_open_generic(struct inode *inode, struct file *filp);
 570int tracing_open_generic_tr(struct inode *inode, struct file *filp);
 571bool tracing_is_disabled(void);
 572bool tracer_tracing_is_on(struct trace_array *tr);
 573void tracer_tracing_on(struct trace_array *tr);
 574void tracer_tracing_off(struct trace_array *tr);
 575struct dentry *trace_create_file(const char *name,
 576                                 umode_t mode,
 577                                 struct dentry *parent,
 578                                 void *data,
 579                                 const struct file_operations *fops);
 580
 581int tracing_init_dentry(void);
 582
 583struct ring_buffer_event;
 584
 585struct ring_buffer_event *
 586trace_buffer_lock_reserve(struct trace_buffer *buffer,
 587                          int type,
 588                          unsigned long len,
 589                          unsigned int trace_ctx);
 590
 591struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
 592                                                struct trace_array_cpu *data);
 593
 594struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
 595                                          int *ent_cpu, u64 *ent_ts);
 596
 597void trace_buffer_unlock_commit_nostack(struct trace_buffer *buffer,
 598                                        struct ring_buffer_event *event);
 599
 600bool trace_is_tracepoint_string(const char *str);
 601const char *trace_event_format(struct trace_iterator *iter, const char *fmt);
 602void trace_check_vprintf(struct trace_iterator *iter, const char *fmt,
 603                         va_list ap);
 604
 605int trace_empty(struct trace_iterator *iter);
 606
 607void *trace_find_next_entry_inc(struct trace_iterator *iter);
 608
 609void trace_init_global_iter(struct trace_iterator *iter);
 610
 611void tracing_iter_reset(struct trace_iterator *iter, int cpu);
 612
 613unsigned long trace_total_entries_cpu(struct trace_array *tr, int cpu);
 614unsigned long trace_total_entries(struct trace_array *tr);
 615
 616void trace_function(struct trace_array *tr,
 617                    unsigned long ip,
 618                    unsigned long parent_ip,
 619                    unsigned int trace_ctx);
 620void trace_graph_function(struct trace_array *tr,
 621                    unsigned long ip,
 622                    unsigned long parent_ip,
 623                    unsigned int trace_ctx);
 624void trace_latency_header(struct seq_file *m);
 625void trace_default_header(struct seq_file *m);
 626void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
 627
 628void trace_graph_return(struct ftrace_graph_ret *trace);
 629int trace_graph_entry(struct ftrace_graph_ent *trace);
 630void set_graph_array(struct trace_array *tr);
 631
 632void tracing_start_cmdline_record(void);
 633void tracing_stop_cmdline_record(void);
 634void tracing_start_tgid_record(void);
 635void tracing_stop_tgid_record(void);
 636
 637int register_tracer(struct tracer *type);
 638int is_tracing_stopped(void);
 639
 640loff_t tracing_lseek(struct file *file, loff_t offset, int whence);
 641
 642extern cpumask_var_t __read_mostly tracing_buffer_mask;
 643
 644#define for_each_tracing_cpu(cpu)       \
 645        for_each_cpu(cpu, tracing_buffer_mask)
 646
 647extern unsigned long nsecs_to_usecs(unsigned long nsecs);
 648
 649extern unsigned long tracing_thresh;
 650
 651/* PID filtering */
 652
 653extern int pid_max;
 654
 655bool trace_find_filtered_pid(struct trace_pid_list *filtered_pids,
 656                             pid_t search_pid);
 657bool trace_ignore_this_task(struct trace_pid_list *filtered_pids,
 658                            struct trace_pid_list *filtered_no_pids,
 659                            struct task_struct *task);
 660void trace_filter_add_remove_task(struct trace_pid_list *pid_list,
 661                                  struct task_struct *self,
 662                                  struct task_struct *task);
 663void *trace_pid_next(struct trace_pid_list *pid_list, void *v, loff_t *pos);
 664void *trace_pid_start(struct trace_pid_list *pid_list, loff_t *pos);
 665int trace_pid_show(struct seq_file *m, void *v);
 666void trace_free_pid_list(struct trace_pid_list *pid_list);
 667int trace_pid_write(struct trace_pid_list *filtered_pids,
 668                    struct trace_pid_list **new_pid_list,
 669                    const char __user *ubuf, size_t cnt);
 670
 671#ifdef CONFIG_TRACER_MAX_TRACE
 672void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu,
 673                   void *cond_data);
 674void update_max_tr_single(struct trace_array *tr,
 675                          struct task_struct *tsk, int cpu);
 676#endif /* CONFIG_TRACER_MAX_TRACE */
 677
 678#if (defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER)) && \
 679        defined(CONFIG_FSNOTIFY)
 680
 681void latency_fsnotify(struct trace_array *tr);
 682
 683#else
 684
 685static inline void latency_fsnotify(struct trace_array *tr) { }
 686
 687#endif
 688
 689#ifdef CONFIG_STACKTRACE
 690void __trace_stack(struct trace_array *tr, unsigned int trace_ctx, int skip);
 691#else
 692static inline void __trace_stack(struct trace_array *tr, unsigned int trace_ctx,
 693                                 int skip)
 694{
 695}
 696#endif /* CONFIG_STACKTRACE */
 697
 698void trace_last_func_repeats(struct trace_array *tr,
 699                             struct trace_func_repeats *last_info,
 700                             unsigned int trace_ctx);
 701
 702extern u64 ftrace_now(int cpu);
 703
 704extern void trace_find_cmdline(int pid, char comm[]);
 705extern int trace_find_tgid(int pid);
 706extern void trace_event_follow_fork(struct trace_array *tr, bool enable);
 707
 708#ifdef CONFIG_DYNAMIC_FTRACE
 709extern unsigned long ftrace_update_tot_cnt;
 710extern unsigned long ftrace_number_of_pages;
 711extern unsigned long ftrace_number_of_groups;
 712void ftrace_init_trace_array(struct trace_array *tr);
 713#else
 714static inline void ftrace_init_trace_array(struct trace_array *tr) { }
 715#endif
 716#define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
 717extern int DYN_FTRACE_TEST_NAME(void);
 718#define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
 719extern int DYN_FTRACE_TEST_NAME2(void);
 720
 721extern bool ring_buffer_expanded;
 722extern bool tracing_selftest_disabled;
 723
 724#ifdef CONFIG_FTRACE_STARTUP_TEST
 725extern void __init disable_tracing_selftest(const char *reason);
 726
 727extern int trace_selftest_startup_function(struct tracer *trace,
 728                                           struct trace_array *tr);
 729extern int trace_selftest_startup_function_graph(struct tracer *trace,
 730                                                 struct trace_array *tr);
 731extern int trace_selftest_startup_irqsoff(struct tracer *trace,
 732                                          struct trace_array *tr);
 733extern int trace_selftest_startup_preemptoff(struct tracer *trace,
 734                                             struct trace_array *tr);
 735extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
 736                                                 struct trace_array *tr);
 737extern int trace_selftest_startup_wakeup(struct tracer *trace,
 738                                         struct trace_array *tr);
 739extern int trace_selftest_startup_nop(struct tracer *trace,
 740                                         struct trace_array *tr);
 741extern int trace_selftest_startup_branch(struct tracer *trace,
 742                                         struct trace_array *tr);
 743/*
 744 * Tracer data references selftest functions that only occur
 745 * on boot up. These can be __init functions. Thus, when selftests
 746 * are enabled, then the tracers need to reference __init functions.
 747 */
 748#define __tracer_data           __refdata
 749#else
 750static inline void __init disable_tracing_selftest(const char *reason)
 751{
 752}
 753/* Tracers are seldom changed. Optimize when selftests are disabled. */
 754#define __tracer_data           __read_mostly
 755#endif /* CONFIG_FTRACE_STARTUP_TEST */
 756
 757extern void *head_page(struct trace_array_cpu *data);
 758extern unsigned long long ns2usecs(u64 nsec);
 759extern int
 760trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
 761extern int
 762trace_vprintk(unsigned long ip, const char *fmt, va_list args);
 763extern int
 764trace_array_vprintk(struct trace_array *tr,
 765                    unsigned long ip, const char *fmt, va_list args);
 766int trace_array_printk_buf(struct trace_buffer *buffer,
 767                           unsigned long ip, const char *fmt, ...);
 768void trace_printk_seq(struct trace_seq *s);
 769enum print_line_t print_trace_line(struct trace_iterator *iter);
 770
 771extern char trace_find_mark(unsigned long long duration);
 772
 773struct ftrace_hash;
 774
 775struct ftrace_mod_load {
 776        struct list_head        list;
 777        char                    *func;
 778        char                    *module;
 779        int                      enable;
 780};
 781
 782enum {
 783        FTRACE_HASH_FL_MOD      = (1 << 0),
 784};
 785
 786struct ftrace_hash {
 787        unsigned long           size_bits;
 788        struct hlist_head       *buckets;
 789        unsigned long           count;
 790        unsigned long           flags;
 791        struct rcu_head         rcu;
 792};
 793
 794struct ftrace_func_entry *
 795ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip);
 796
 797static __always_inline bool ftrace_hash_empty(struct ftrace_hash *hash)
 798{
 799        return !hash || !(hash->count || (hash->flags & FTRACE_HASH_FL_MOD));
 800}
 801
 802/* Standard output formatting function used for function return traces */
 803#ifdef CONFIG_FUNCTION_GRAPH_TRACER
 804
 805/* Flag options */
 806#define TRACE_GRAPH_PRINT_OVERRUN       0x1
 807#define TRACE_GRAPH_PRINT_CPU           0x2
 808#define TRACE_GRAPH_PRINT_OVERHEAD      0x4
 809#define TRACE_GRAPH_PRINT_PROC          0x8
 810#define TRACE_GRAPH_PRINT_DURATION      0x10
 811#define TRACE_GRAPH_PRINT_ABS_TIME      0x20
 812#define TRACE_GRAPH_PRINT_REL_TIME      0x40
 813#define TRACE_GRAPH_PRINT_IRQS          0x80
 814#define TRACE_GRAPH_PRINT_TAIL          0x100
 815#define TRACE_GRAPH_SLEEP_TIME          0x200
 816#define TRACE_GRAPH_GRAPH_TIME          0x400
 817#define TRACE_GRAPH_PRINT_FILL_SHIFT    28
 818#define TRACE_GRAPH_PRINT_FILL_MASK     (0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT)
 819
 820extern void ftrace_graph_sleep_time_control(bool enable);
 821
 822#ifdef CONFIG_FUNCTION_PROFILER
 823extern void ftrace_graph_graph_time_control(bool enable);
 824#else
 825static inline void ftrace_graph_graph_time_control(bool enable) { }
 826#endif
 827
 828extern enum print_line_t
 829print_graph_function_flags(struct trace_iterator *iter, u32 flags);
 830extern void print_graph_headers_flags(struct seq_file *s, u32 flags);
 831extern void
 832trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
 833extern void graph_trace_open(struct trace_iterator *iter);
 834extern void graph_trace_close(struct trace_iterator *iter);
 835extern int __trace_graph_entry(struct trace_array *tr,
 836                               struct ftrace_graph_ent *trace,
 837                               unsigned int trace_ctx);
 838extern void __trace_graph_return(struct trace_array *tr,
 839                                 struct ftrace_graph_ret *trace,
 840                                 unsigned int trace_ctx);
 841
 842#ifdef CONFIG_DYNAMIC_FTRACE
 843extern struct ftrace_hash __rcu *ftrace_graph_hash;
 844extern struct ftrace_hash __rcu *ftrace_graph_notrace_hash;
 845
 846static inline int ftrace_graph_addr(struct ftrace_graph_ent *trace)
 847{
 848        unsigned long addr = trace->func;
 849        int ret = 0;
 850        struct ftrace_hash *hash;
 851
 852        preempt_disable_notrace();
 853
 854        /*
 855         * Have to open code "rcu_dereference_sched()" because the
 856         * function graph tracer can be called when RCU is not
 857         * "watching".
 858         * Protected with schedule_on_each_cpu(ftrace_sync)
 859         */
 860        hash = rcu_dereference_protected(ftrace_graph_hash, !preemptible());
 861
 862        if (ftrace_hash_empty(hash)) {
 863                ret = 1;
 864                goto out;
 865        }
 866
 867        if (ftrace_lookup_ip(hash, addr)) {
 868
 869                /*
 870                 * This needs to be cleared on the return functions
 871                 * when the depth is zero.
 872                 */
 873                trace_recursion_set(TRACE_GRAPH_BIT);
 874                trace_recursion_set_depth(trace->depth);
 875
 876                /*
 877                 * If no irqs are to be traced, but a set_graph_function
 878                 * is set, and called by an interrupt handler, we still
 879                 * want to trace it.
 880                 */
 881                if (in_irq())
 882                        trace_recursion_set(TRACE_IRQ_BIT);
 883                else
 884                        trace_recursion_clear(TRACE_IRQ_BIT);
 885                ret = 1;
 886        }
 887
 888out:
 889        preempt_enable_notrace();
 890        return ret;
 891}
 892
 893static inline void ftrace_graph_addr_finish(struct ftrace_graph_ret *trace)
 894{
 895        if (trace_recursion_test(TRACE_GRAPH_BIT) &&
 896            trace->depth == trace_recursion_depth())
 897                trace_recursion_clear(TRACE_GRAPH_BIT);
 898}
 899
 900static inline int ftrace_graph_notrace_addr(unsigned long addr)
 901{
 902        int ret = 0;
 903        struct ftrace_hash *notrace_hash;
 904
 905        preempt_disable_notrace();
 906
 907        /*
 908         * Have to open code "rcu_dereference_sched()" because the
 909         * function graph tracer can be called when RCU is not
 910         * "watching".
 911         * Protected with schedule_on_each_cpu(ftrace_sync)
 912         */
 913        notrace_hash = rcu_dereference_protected(ftrace_graph_notrace_hash,
 914                                                 !preemptible());
 915
 916        if (ftrace_lookup_ip(notrace_hash, addr))
 917                ret = 1;
 918
 919        preempt_enable_notrace();
 920        return ret;
 921}
 922#else
 923static inline int ftrace_graph_addr(struct ftrace_graph_ent *trace)
 924{
 925        return 1;
 926}
 927
 928static inline int ftrace_graph_notrace_addr(unsigned long addr)
 929{
 930        return 0;
 931}
 932static inline void ftrace_graph_addr_finish(struct ftrace_graph_ret *trace)
 933{ }
 934#endif /* CONFIG_DYNAMIC_FTRACE */
 935
 936extern unsigned int fgraph_max_depth;
 937
 938static inline bool ftrace_graph_ignore_func(struct ftrace_graph_ent *trace)
 939{
 940        /* trace it when it is-nested-in or is a function enabled. */
 941        return !(trace_recursion_test(TRACE_GRAPH_BIT) ||
 942                 ftrace_graph_addr(trace)) ||
 943                (trace->depth < 0) ||
 944                (fgraph_max_depth && trace->depth >= fgraph_max_depth);
 945}
 946
 947#else /* CONFIG_FUNCTION_GRAPH_TRACER */
 948static inline enum print_line_t
 949print_graph_function_flags(struct trace_iterator *iter, u32 flags)
 950{
 951        return TRACE_TYPE_UNHANDLED;
 952}
 953#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
 954
 955extern struct list_head ftrace_pids;
 956
 957#ifdef CONFIG_FUNCTION_TRACER
 958
 959#define FTRACE_PID_IGNORE       -1
 960#define FTRACE_PID_TRACE        -2
 961
 962struct ftrace_func_command {
 963        struct list_head        list;
 964        char                    *name;
 965        int                     (*func)(struct trace_array *tr,
 966                                        struct ftrace_hash *hash,
 967                                        char *func, char *cmd,
 968                                        char *params, int enable);
 969};
 970extern bool ftrace_filter_param __initdata;
 971static inline int ftrace_trace_task(struct trace_array *tr)
 972{
 973        return this_cpu_read(tr->array_buffer.data->ftrace_ignore_pid) !=
 974                FTRACE_PID_IGNORE;
 975}
 976extern int ftrace_is_dead(void);
 977int ftrace_create_function_files(struct trace_array *tr,
 978                                 struct dentry *parent);
 979void ftrace_destroy_function_files(struct trace_array *tr);
 980int ftrace_allocate_ftrace_ops(struct trace_array *tr);
 981void ftrace_free_ftrace_ops(struct trace_array *tr);
 982void ftrace_init_global_array_ops(struct trace_array *tr);
 983void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func);
 984void ftrace_reset_array_ops(struct trace_array *tr);
 985void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer);
 986void ftrace_init_tracefs_toplevel(struct trace_array *tr,
 987                                  struct dentry *d_tracer);
 988void ftrace_clear_pids(struct trace_array *tr);
 989int init_function_trace(void);
 990void ftrace_pid_follow_fork(struct trace_array *tr, bool enable);
 991#else
 992static inline int ftrace_trace_task(struct trace_array *tr)
 993{
 994        return 1;
 995}
 996static inline int ftrace_is_dead(void) { return 0; }
 997static inline int
 998ftrace_create_function_files(struct trace_array *tr,
 999                             struct dentry *parent)
1000{
1001        return 0;
1002}
1003static inline int ftrace_allocate_ftrace_ops(struct trace_array *tr)
1004{
1005        return 0;
1006}
1007static inline void ftrace_free_ftrace_ops(struct trace_array *tr) { }
1008static inline void ftrace_destroy_function_files(struct trace_array *tr) { }
1009static inline __init void
1010ftrace_init_global_array_ops(struct trace_array *tr) { }
1011static inline void ftrace_reset_array_ops(struct trace_array *tr) { }
1012static inline void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d) { }
1013static inline void ftrace_init_tracefs_toplevel(struct trace_array *tr, struct dentry *d) { }
1014static inline void ftrace_clear_pids(struct trace_array *tr) { }
1015static inline int init_function_trace(void) { return 0; }
1016static inline void ftrace_pid_follow_fork(struct trace_array *tr, bool enable) { }
1017/* ftace_func_t type is not defined, use macro instead of static inline */
1018#define ftrace_init_array_ops(tr, func) do { } while (0)
1019#endif /* CONFIG_FUNCTION_TRACER */
1020
1021#if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE)
1022
1023struct ftrace_probe_ops {
1024        void                    (*func)(unsigned long ip,
1025                                        unsigned long parent_ip,
1026                                        struct trace_array *tr,
1027                                        struct ftrace_probe_ops *ops,
1028                                        void *data);
1029        int                     (*init)(struct ftrace_probe_ops *ops,
1030                                        struct trace_array *tr,
1031                                        unsigned long ip, void *init_data,
1032                                        void **data);
1033        void                    (*free)(struct ftrace_probe_ops *ops,
1034                                        struct trace_array *tr,
1035                                        unsigned long ip, void *data);
1036        int                     (*print)(struct seq_file *m,
1037                                         unsigned long ip,
1038                                         struct ftrace_probe_ops *ops,
1039                                         void *data);
1040};
1041
1042struct ftrace_func_mapper;
1043typedef int (*ftrace_mapper_func)(void *data);
1044
1045struct ftrace_func_mapper *allocate_ftrace_func_mapper(void);
1046void **ftrace_func_mapper_find_ip(struct ftrace_func_mapper *mapper,
1047                                           unsigned long ip);
1048int ftrace_func_mapper_add_ip(struct ftrace_func_mapper *mapper,
1049                               unsigned long ip, void *data);
1050void *ftrace_func_mapper_remove_ip(struct ftrace_func_mapper *mapper,
1051                                   unsigned long ip);
1052void free_ftrace_func_mapper(struct ftrace_func_mapper *mapper,
1053                             ftrace_mapper_func free_func);
1054
1055extern int
1056register_ftrace_function_probe(char *glob, struct trace_array *tr,
1057                               struct ftrace_probe_ops *ops, void *data);
1058extern int
1059unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr,
1060                                      struct ftrace_probe_ops *ops);
1061extern void clear_ftrace_function_probes(struct trace_array *tr);
1062
1063int register_ftrace_command(struct ftrace_func_command *cmd);
1064int unregister_ftrace_command(struct ftrace_func_command *cmd);
1065
1066void ftrace_create_filter_files(struct ftrace_ops *ops,
1067                                struct dentry *parent);
1068void ftrace_destroy_filter_files(struct ftrace_ops *ops);
1069
1070extern int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf,
1071                             int len, int reset);
1072extern int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,
1073                              int len, int reset);
1074#else
1075struct ftrace_func_command;
1076
1077static inline __init int register_ftrace_command(struct ftrace_func_command *cmd)
1078{
1079        return -EINVAL;
1080}
1081static inline __init int unregister_ftrace_command(char *cmd_name)
1082{
1083        return -EINVAL;
1084}
1085static inline void clear_ftrace_function_probes(struct trace_array *tr)
1086{
1087}
1088
1089/*
1090 * The ops parameter passed in is usually undefined.
1091 * This must be a macro.
1092 */
1093#define ftrace_create_filter_files(ops, parent) do { } while (0)
1094#define ftrace_destroy_filter_files(ops) do { } while (0)
1095#endif /* CONFIG_FUNCTION_TRACER && CONFIG_DYNAMIC_FTRACE */
1096
1097bool ftrace_event_is_function(struct trace_event_call *call);
1098
1099/*
1100 * struct trace_parser - servers for reading the user input separated by spaces
1101 * @cont: set if the input is not complete - no final space char was found
1102 * @buffer: holds the parsed user input
1103 * @idx: user input length
1104 * @size: buffer size
1105 */
1106struct trace_parser {
1107        bool            cont;
1108        char            *buffer;
1109        unsigned        idx;
1110        unsigned        size;
1111};
1112
1113static inline bool trace_parser_loaded(struct trace_parser *parser)
1114{
1115        return (parser->idx != 0);
1116}
1117
1118static inline bool trace_parser_cont(struct trace_parser *parser)
1119{
1120        return parser->cont;
1121}
1122
1123static inline void trace_parser_clear(struct trace_parser *parser)
1124{
1125        parser->cont = false;
1126        parser->idx = 0;
1127}
1128
1129extern int trace_parser_get_init(struct trace_parser *parser, int size);
1130extern void trace_parser_put(struct trace_parser *parser);
1131extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
1132        size_t cnt, loff_t *ppos);
1133
1134/*
1135 * Only create function graph options if function graph is configured.
1136 */
1137#ifdef CONFIG_FUNCTION_GRAPH_TRACER
1138# define FGRAPH_FLAGS                                           \
1139                C(DISPLAY_GRAPH,        "display-graph"),
1140#else
1141# define FGRAPH_FLAGS
1142#endif
1143
1144#ifdef CONFIG_BRANCH_TRACER
1145# define BRANCH_FLAGS                                   \
1146                C(BRANCH,               "branch"),
1147#else
1148# define BRANCH_FLAGS
1149#endif
1150
1151#ifdef CONFIG_FUNCTION_TRACER
1152# define FUNCTION_FLAGS                                         \
1153                C(FUNCTION,             "function-trace"),      \
1154                C(FUNC_FORK,            "function-fork"),
1155# define FUNCTION_DEFAULT_FLAGS         TRACE_ITER_FUNCTION
1156#else
1157# define FUNCTION_FLAGS
1158# define FUNCTION_DEFAULT_FLAGS         0UL
1159# define TRACE_ITER_FUNC_FORK           0UL
1160#endif
1161
1162#ifdef CONFIG_STACKTRACE
1163# define STACK_FLAGS                            \
1164                C(STACKTRACE,           "stacktrace"),
1165#else
1166# define STACK_FLAGS
1167#endif
1168
1169/*
1170 * trace_iterator_flags is an enumeration that defines bit
1171 * positions into trace_flags that controls the output.
1172 *
1173 * NOTE: These bits must match the trace_options array in
1174 *       trace.c (this macro guarantees it).
1175 */
1176#define TRACE_FLAGS                                             \
1177                C(PRINT_PARENT,         "print-parent"),        \
1178                C(SYM_OFFSET,           "sym-offset"),          \
1179                C(SYM_ADDR,             "sym-addr"),            \
1180                C(VERBOSE,              "verbose"),             \
1181                C(RAW,                  "raw"),                 \
1182                C(HEX,                  "hex"),                 \
1183                C(BIN,                  "bin"),                 \
1184                C(BLOCK,                "block"),               \
1185                C(PRINTK,               "trace_printk"),        \
1186                C(ANNOTATE,             "annotate"),            \
1187                C(USERSTACKTRACE,       "userstacktrace"),      \
1188                C(SYM_USEROBJ,          "sym-userobj"),         \
1189                C(PRINTK_MSGONLY,       "printk-msg-only"),     \
1190                C(CONTEXT_INFO,         "context-info"),   /* Print pid/cpu/time */ \
1191                C(LATENCY_FMT,          "latency-format"),      \
1192                C(RECORD_CMD,           "record-cmd"),          \
1193                C(RECORD_TGID,          "record-tgid"),         \
1194                C(OVERWRITE,            "overwrite"),           \
1195                C(STOP_ON_FREE,         "disable_on_free"),     \
1196                C(IRQ_INFO,             "irq-info"),            \
1197                C(MARKERS,              "markers"),             \
1198                C(EVENT_FORK,           "event-fork"),          \
1199                C(PAUSE_ON_TRACE,       "pause-on-trace"),      \
1200                C(HASH_PTR,             "hash-ptr"),    /* Print hashed pointer */ \
1201                FUNCTION_FLAGS                                  \
1202                FGRAPH_FLAGS                                    \
1203                STACK_FLAGS                                     \
1204                BRANCH_FLAGS
1205
1206/*
1207 * By defining C, we can make TRACE_FLAGS a list of bit names
1208 * that will define the bits for the flag masks.
1209 */
1210#undef C
1211#define C(a, b) TRACE_ITER_##a##_BIT
1212
1213enum trace_iterator_bits {
1214        TRACE_FLAGS
1215        /* Make sure we don't go more than we have bits for */
1216        TRACE_ITER_LAST_BIT
1217};
1218
1219/*
1220 * By redefining C, we can make TRACE_FLAGS a list of masks that
1221 * use the bits as defined above.
1222 */
1223#undef C
1224#define C(a, b) TRACE_ITER_##a = (1 << TRACE_ITER_##a##_BIT)
1225
1226enum trace_iterator_flags { TRACE_FLAGS };
1227
1228/*
1229 * TRACE_ITER_SYM_MASK masks the options in trace_flags that
1230 * control the output of kernel symbols.
1231 */
1232#define TRACE_ITER_SYM_MASK \
1233        (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
1234
1235extern struct tracer nop_trace;
1236
1237#ifdef CONFIG_BRANCH_TRACER
1238extern int enable_branch_tracing(struct trace_array *tr);
1239extern void disable_branch_tracing(void);
1240static inline int trace_branch_enable(struct trace_array *tr)
1241{
1242        if (tr->trace_flags & TRACE_ITER_BRANCH)
1243                return enable_branch_tracing(tr);
1244        return 0;
1245}
1246static inline void trace_branch_disable(void)
1247{
1248        /* due to races, always disable */
1249        disable_branch_tracing();
1250}
1251#else
1252static inline int trace_branch_enable(struct trace_array *tr)
1253{
1254        return 0;
1255}
1256static inline void trace_branch_disable(void)
1257{
1258}
1259#endif /* CONFIG_BRANCH_TRACER */
1260
1261/* set ring buffers to default size if not already done so */
1262int tracing_update_buffers(void);
1263
1264struct ftrace_event_field {
1265        struct list_head        link;
1266        const char              *name;
1267        const char              *type;
1268        int                     filter_type;
1269        int                     offset;
1270        int                     size;
1271        int                     is_signed;
1272};
1273
1274struct prog_entry;
1275
1276struct event_filter {
1277        struct prog_entry __rcu *prog;
1278        char                    *filter_string;
1279};
1280
1281struct event_subsystem {
1282        struct list_head        list;
1283        const char              *name;
1284        struct event_filter     *filter;
1285        int                     ref_count;
1286};
1287
1288struct trace_subsystem_dir {
1289        struct list_head                list;
1290        struct event_subsystem          *subsystem;
1291        struct trace_array              *tr;
1292        struct dentry                   *entry;
1293        int                             ref_count;
1294        int                             nr_events;
1295};
1296
1297extern int call_filter_check_discard(struct trace_event_call *call, void *rec,
1298                                     struct trace_buffer *buffer,
1299                                     struct ring_buffer_event *event);
1300
1301void trace_buffer_unlock_commit_regs(struct trace_array *tr,
1302                                     struct trace_buffer *buffer,
1303                                     struct ring_buffer_event *event,
1304                                     unsigned int trcace_ctx,
1305                                     struct pt_regs *regs);
1306
1307static inline void trace_buffer_unlock_commit(struct trace_array *tr,
1308                                              struct trace_buffer *buffer,
1309                                              struct ring_buffer_event *event,
1310                                              unsigned int trace_ctx)
1311{
1312        trace_buffer_unlock_commit_regs(tr, buffer, event, trace_ctx, NULL);
1313}
1314
1315DECLARE_PER_CPU(struct ring_buffer_event *, trace_buffered_event);
1316DECLARE_PER_CPU(int, trace_buffered_event_cnt);
1317void trace_buffered_event_disable(void);
1318void trace_buffered_event_enable(void);
1319
1320static inline void
1321__trace_event_discard_commit(struct trace_buffer *buffer,
1322                             struct ring_buffer_event *event)
1323{
1324        if (this_cpu_read(trace_buffered_event) == event) {
1325                /* Simply release the temp buffer */
1326                this_cpu_dec(trace_buffered_event_cnt);
1327                return;
1328        }
1329        ring_buffer_discard_commit(buffer, event);
1330}
1331
1332/*
1333 * Helper function for event_trigger_unlock_commit{_regs}().
1334 * If there are event triggers attached to this event that requires
1335 * filtering against its fields, then they will be called as the
1336 * entry already holds the field information of the current event.
1337 *
1338 * It also checks if the event should be discarded or not.
1339 * It is to be discarded if the event is soft disabled and the
1340 * event was only recorded to process triggers, or if the event
1341 * filter is active and this event did not match the filters.
1342 *
1343 * Returns true if the event is discarded, false otherwise.
1344 */
1345static inline bool
1346__event_trigger_test_discard(struct trace_event_file *file,
1347                             struct trace_buffer *buffer,
1348                             struct ring_buffer_event *event,
1349                             void *entry,
1350                             enum event_trigger_type *tt)
1351{
1352        unsigned long eflags = file->flags;
1353
1354        if (eflags & EVENT_FILE_FL_TRIGGER_COND)
1355                *tt = event_triggers_call(file, buffer, entry, event);
1356
1357        if (test_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &file->flags) ||
1358            (unlikely(file->flags & EVENT_FILE_FL_FILTERED) &&
1359             !filter_match_preds(file->filter, entry))) {
1360                __trace_event_discard_commit(buffer, event);
1361                return true;
1362        }
1363
1364        return false;
1365}
1366
1367/**
1368 * event_trigger_unlock_commit - handle triggers and finish event commit
1369 * @file: The file pointer associated with the event
1370 * @buffer: The ring buffer that the event is being written to
1371 * @event: The event meta data in the ring buffer
1372 * @entry: The event itself
1373 * @trace_ctx: The tracing context flags.
1374 *
1375 * This is a helper function to handle triggers that require data
1376 * from the event itself. It also tests the event against filters and
1377 * if the event is soft disabled and should be discarded.
1378 */
1379static inline void
1380event_trigger_unlock_commit(struct trace_event_file *file,
1381                            struct trace_buffer *buffer,
1382                            struct ring_buffer_event *event,
1383                            void *entry, unsigned int trace_ctx)
1384{
1385        enum event_trigger_type tt = ETT_NONE;
1386
1387        if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
1388                trace_buffer_unlock_commit(file->tr, buffer, event, trace_ctx);
1389
1390        if (tt)
1391                event_triggers_post_call(file, tt);
1392}
1393
1394/**
1395 * event_trigger_unlock_commit_regs - handle triggers and finish event commit
1396 * @file: The file pointer associated with the event
1397 * @buffer: The ring buffer that the event is being written to
1398 * @event: The event meta data in the ring buffer
1399 * @entry: The event itself
1400 * @trace_ctx: The tracing context flags.
1401 *
1402 * This is a helper function to handle triggers that require data
1403 * from the event itself. It also tests the event against filters and
1404 * if the event is soft disabled and should be discarded.
1405 *
1406 * Same as event_trigger_unlock_commit() but calls
1407 * trace_buffer_unlock_commit_regs() instead of trace_buffer_unlock_commit().
1408 */
1409static inline void
1410event_trigger_unlock_commit_regs(struct trace_event_file *file,
1411                                 struct trace_buffer *buffer,
1412                                 struct ring_buffer_event *event,
1413                                 void *entry, unsigned int trace_ctx,
1414                                 struct pt_regs *regs)
1415{
1416        enum event_trigger_type tt = ETT_NONE;
1417
1418        if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
1419                trace_buffer_unlock_commit_regs(file->tr, buffer, event,
1420                                                trace_ctx, regs);
1421
1422        if (tt)
1423                event_triggers_post_call(file, tt);
1424}
1425
1426#define FILTER_PRED_INVALID     ((unsigned short)-1)
1427#define FILTER_PRED_IS_RIGHT    (1 << 15)
1428#define FILTER_PRED_FOLD        (1 << 15)
1429
1430/*
1431 * The max preds is the size of unsigned short with
1432 * two flags at the MSBs. One bit is used for both the IS_RIGHT
1433 * and FOLD flags. The other is reserved.
1434 *
1435 * 2^14 preds is way more than enough.
1436 */
1437#define MAX_FILTER_PRED         16384
1438
1439struct filter_pred;
1440struct regex;
1441
1442typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event);
1443
1444typedef int (*regex_match_func)(char *str, struct regex *r, int len);
1445
1446enum regex_type {
1447        MATCH_FULL = 0,
1448        MATCH_FRONT_ONLY,
1449        MATCH_MIDDLE_ONLY,
1450        MATCH_END_ONLY,
1451        MATCH_GLOB,
1452        MATCH_INDEX,
1453};
1454
1455struct regex {
1456        char                    pattern[MAX_FILTER_STR_VAL];
1457        int                     len;
1458        int                     field_len;
1459        regex_match_func        match;
1460};
1461
1462struct filter_pred {
1463        filter_pred_fn_t        fn;
1464        u64                     val;
1465        struct regex            regex;
1466        unsigned short          *ops;
1467        struct ftrace_event_field *field;
1468        int                     offset;
1469        int                     not;
1470        int                     op;
1471};
1472
1473static inline bool is_string_field(struct ftrace_event_field *field)
1474{
1475        return field->filter_type == FILTER_DYN_STRING ||
1476               field->filter_type == FILTER_STATIC_STRING ||
1477               field->filter_type == FILTER_PTR_STRING ||
1478               field->filter_type == FILTER_COMM;
1479}
1480
1481static inline bool is_function_field(struct ftrace_event_field *field)
1482{
1483        return field->filter_type == FILTER_TRACE_FN;
1484}
1485
1486extern enum regex_type
1487filter_parse_regex(char *buff, int len, char **search, int *not);
1488extern void print_event_filter(struct trace_event_file *file,
1489                               struct trace_seq *s);
1490extern int apply_event_filter(struct trace_event_file *file,
1491                              char *filter_string);
1492extern int apply_subsystem_event_filter(struct trace_subsystem_dir *dir,
1493                                        char *filter_string);
1494extern void print_subsystem_event_filter(struct event_subsystem *system,
1495                                         struct trace_seq *s);
1496extern int filter_assign_type(const char *type);
1497extern int create_event_filter(struct trace_array *tr,
1498                               struct trace_event_call *call,
1499                               char *filter_str, bool set_str,
1500                               struct event_filter **filterp);
1501extern void free_event_filter(struct event_filter *filter);
1502
1503struct ftrace_event_field *
1504trace_find_event_field(struct trace_event_call *call, char *name);
1505
1506extern void trace_event_enable_cmd_record(bool enable);
1507extern void trace_event_enable_tgid_record(bool enable);
1508
1509extern int event_trace_init(void);
1510extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr);
1511extern int event_trace_del_tracer(struct trace_array *tr);
1512extern void __trace_early_add_events(struct trace_array *tr);
1513
1514extern struct trace_event_file *__find_event_file(struct trace_array *tr,
1515                                                  const char *system,
1516                                                  const char *event);
1517extern struct trace_event_file *find_event_file(struct trace_array *tr,
1518                                                const char *system,
1519                                                const char *event);
1520
1521static inline void *event_file_data(struct file *filp)
1522{
1523        return READ_ONCE(file_inode(filp)->i_private);
1524}
1525
1526extern struct mutex event_mutex;
1527extern struct list_head ftrace_events;
1528
1529extern const struct file_operations event_trigger_fops;
1530extern const struct file_operations event_hist_fops;
1531extern const struct file_operations event_hist_debug_fops;
1532extern const struct file_operations event_inject_fops;
1533
1534#ifdef CONFIG_HIST_TRIGGERS
1535extern int register_trigger_hist_cmd(void);
1536extern int register_trigger_hist_enable_disable_cmds(void);
1537#else
1538static inline int register_trigger_hist_cmd(void) { return 0; }
1539static inline int register_trigger_hist_enable_disable_cmds(void) { return 0; }
1540#endif
1541
1542extern int register_trigger_cmds(void);
1543extern void clear_event_triggers(struct trace_array *tr);
1544
1545struct event_trigger_data {
1546        unsigned long                   count;
1547        int                             ref;
1548        struct event_trigger_ops        *ops;
1549        struct event_command            *cmd_ops;
1550        struct event_filter __rcu       *filter;
1551        char                            *filter_str;
1552        void                            *private_data;
1553        bool                            paused;
1554        bool                            paused_tmp;
1555        struct list_head                list;
1556        char                            *name;
1557        struct list_head                named_list;
1558        struct event_trigger_data       *named_data;
1559};
1560
1561/* Avoid typos */
1562#define ENABLE_EVENT_STR        "enable_event"
1563#define DISABLE_EVENT_STR       "disable_event"
1564#define ENABLE_HIST_STR         "enable_hist"
1565#define DISABLE_HIST_STR        "disable_hist"
1566
1567struct enable_trigger_data {
1568        struct trace_event_file         *file;
1569        bool                            enable;
1570        bool                            hist;
1571};
1572
1573extern int event_enable_trigger_print(struct seq_file *m,
1574                                      struct event_trigger_ops *ops,
1575                                      struct event_trigger_data *data);
1576extern void event_enable_trigger_free(struct event_trigger_ops *ops,
1577                                      struct event_trigger_data *data);
1578extern int event_enable_trigger_func(struct event_command *cmd_ops,
1579                                     struct trace_event_file *file,
1580                                     char *glob, char *cmd, char *param);
1581extern int event_enable_register_trigger(char *glob,
1582                                         struct event_trigger_ops *ops,
1583                                         struct event_trigger_data *data,
1584                                         struct trace_event_file *file);
1585extern void event_enable_unregister_trigger(char *glob,
1586                                            struct event_trigger_ops *ops,
1587                                            struct event_trigger_data *test,
1588                                            struct trace_event_file *file);
1589extern void trigger_data_free(struct event_trigger_data *data);
1590extern int event_trigger_init(struct event_trigger_ops *ops,
1591                              struct event_trigger_data *data);
1592extern int trace_event_trigger_enable_disable(struct trace_event_file *file,
1593                                              int trigger_enable);
1594extern void update_cond_flag(struct trace_event_file *file);
1595extern int set_trigger_filter(char *filter_str,
1596                              struct event_trigger_data *trigger_data,
1597                              struct trace_event_file *file);
1598extern struct event_trigger_data *find_named_trigger(const char *name);
1599extern bool is_named_trigger(struct event_trigger_data *test);
1600extern int save_named_trigger(const char *name,
1601                              struct event_trigger_data *data);
1602extern void del_named_trigger(struct event_trigger_data *data);
1603extern void pause_named_trigger(struct event_trigger_data *data);
1604extern void unpause_named_trigger(struct event_trigger_data *data);
1605extern void set_named_trigger_data(struct event_trigger_data *data,
1606                                   struct event_trigger_data *named_data);
1607extern struct event_trigger_data *
1608get_named_trigger_data(struct event_trigger_data *data);
1609extern int register_event_command(struct event_command *cmd);
1610extern int unregister_event_command(struct event_command *cmd);
1611extern int register_trigger_hist_enable_disable_cmds(void);
1612
1613/**
1614 * struct event_trigger_ops - callbacks for trace event triggers
1615 *
1616 * The methods in this structure provide per-event trigger hooks for
1617 * various trigger operations.
1618 *
1619 * All the methods below, except for @init() and @free(), must be
1620 * implemented.
1621 *
1622 * @func: The trigger 'probe' function called when the triggering
1623 *      event occurs.  The data passed into this callback is the data
1624 *      that was supplied to the event_command @reg() function that
1625 *      registered the trigger (see struct event_command) along with
1626 *      the trace record, rec.
1627 *
1628 * @init: An optional initialization function called for the trigger
1629 *      when the trigger is registered (via the event_command reg()
1630 *      function).  This can be used to perform per-trigger
1631 *      initialization such as incrementing a per-trigger reference
1632 *      count, for instance.  This is usually implemented by the
1633 *      generic utility function @event_trigger_init() (see
1634 *      trace_event_triggers.c).
1635 *
1636 * @free: An optional de-initialization function called for the
1637 *      trigger when the trigger is unregistered (via the
1638 *      event_command @reg() function).  This can be used to perform
1639 *      per-trigger de-initialization such as decrementing a
1640 *      per-trigger reference count and freeing corresponding trigger
1641 *      data, for instance.  This is usually implemented by the
1642 *      generic utility function @event_trigger_free() (see
1643 *      trace_event_triggers.c).
1644 *
1645 * @print: The callback function invoked to have the trigger print
1646 *      itself.  This is usually implemented by a wrapper function
1647 *      that calls the generic utility function @event_trigger_print()
1648 *      (see trace_event_triggers.c).
1649 */
1650struct event_trigger_ops {
1651        void                    (*func)(struct event_trigger_data *data,
1652                                        struct trace_buffer *buffer, void *rec,
1653                                        struct ring_buffer_event *rbe);
1654        int                     (*init)(struct event_trigger_ops *ops,
1655                                        struct event_trigger_data *data);
1656        void                    (*free)(struct event_trigger_ops *ops,
1657                                        struct event_trigger_data *data);
1658        int                     (*print)(struct seq_file *m,
1659                                         struct event_trigger_ops *ops,
1660                                         struct event_trigger_data *data);
1661};
1662
1663/**
1664 * struct event_command - callbacks and data members for event commands
1665 *
1666 * Event commands are invoked by users by writing the command name
1667 * into the 'trigger' file associated with a trace event.  The
1668 * parameters associated with a specific invocation of an event
1669 * command are used to create an event trigger instance, which is
1670 * added to the list of trigger instances associated with that trace
1671 * event.  When the event is hit, the set of triggers associated with
1672 * that event is invoked.
1673 *
1674 * The data members in this structure provide per-event command data
1675 * for various event commands.
1676 *
1677 * All the data members below, except for @post_trigger, must be set
1678 * for each event command.
1679 *
1680 * @name: The unique name that identifies the event command.  This is
1681 *      the name used when setting triggers via trigger files.
1682 *
1683 * @trigger_type: A unique id that identifies the event command
1684 *      'type'.  This value has two purposes, the first to ensure that
1685 *      only one trigger of the same type can be set at a given time
1686 *      for a particular event e.g. it doesn't make sense to have both
1687 *      a traceon and traceoff trigger attached to a single event at
1688 *      the same time, so traceon and traceoff have the same type
1689 *      though they have different names.  The @trigger_type value is
1690 *      also used as a bit value for deferring the actual trigger
1691 *      action until after the current event is finished.  Some
1692 *      commands need to do this if they themselves log to the trace
1693 *      buffer (see the @post_trigger() member below).  @trigger_type
1694 *      values are defined by adding new values to the trigger_type
1695 *      enum in include/linux/trace_events.h.
1696 *
1697 * @flags: See the enum event_command_flags below.
1698 *
1699 * All the methods below, except for @set_filter() and @unreg_all(),
1700 * must be implemented.
1701 *
1702 * @func: The callback function responsible for parsing and
1703 *      registering the trigger written to the 'trigger' file by the
1704 *      user.  It allocates the trigger instance and registers it with
1705 *      the appropriate trace event.  It makes use of the other
1706 *      event_command callback functions to orchestrate this, and is
1707 *      usually implemented by the generic utility function
1708 *      @event_trigger_callback() (see trace_event_triggers.c).
1709 *
1710 * @reg: Adds the trigger to the list of triggers associated with the
1711 *      event, and enables the event trigger itself, after
1712 *      initializing it (via the event_trigger_ops @init() function).
1713 *      This is also where commands can use the @trigger_type value to
1714 *      make the decision as to whether or not multiple instances of
1715 *      the trigger should be allowed.  This is usually implemented by
1716 *      the generic utility function @register_trigger() (see
1717 *      trace_event_triggers.c).
1718 *
1719 * @unreg: Removes the trigger from the list of triggers associated
1720 *      with the event, and disables the event trigger itself, after
1721 *      initializing it (via the event_trigger_ops @free() function).
1722 *      This is usually implemented by the generic utility function
1723 *      @unregister_trigger() (see trace_event_triggers.c).
1724 *
1725 * @unreg_all: An optional function called to remove all the triggers
1726 *      from the list of triggers associated with the event.  Called
1727 *      when a trigger file is opened in truncate mode.
1728 *
1729 * @set_filter: An optional function called to parse and set a filter
1730 *      for the trigger.  If no @set_filter() method is set for the
1731 *      event command, filters set by the user for the command will be
1732 *      ignored.  This is usually implemented by the generic utility
1733 *      function @set_trigger_filter() (see trace_event_triggers.c).
1734 *
1735 * @get_trigger_ops: The callback function invoked to retrieve the
1736 *      event_trigger_ops implementation associated with the command.
1737 */
1738struct event_command {
1739        struct list_head        list;
1740        char                    *name;
1741        enum event_trigger_type trigger_type;
1742        int                     flags;
1743        int                     (*func)(struct event_command *cmd_ops,
1744                                        struct trace_event_file *file,
1745                                        char *glob, char *cmd, char *params);
1746        int                     (*reg)(char *glob,
1747                                       struct event_trigger_ops *ops,
1748                                       struct event_trigger_data *data,
1749                                       struct trace_event_file *file);
1750        void                    (*unreg)(char *glob,
1751                                         struct event_trigger_ops *ops,
1752                                         struct event_trigger_data *data,
1753                                         struct trace_event_file *file);
1754        void                    (*unreg_all)(struct trace_event_file *file);
1755        int                     (*set_filter)(char *filter_str,
1756                                              struct event_trigger_data *data,
1757                                              struct trace_event_file *file);
1758        struct event_trigger_ops *(*get_trigger_ops)(char *cmd, char *param);
1759};
1760
1761/**
1762 * enum event_command_flags - flags for struct event_command
1763 *
1764 * @POST_TRIGGER: A flag that says whether or not this command needs
1765 *      to have its action delayed until after the current event has
1766 *      been closed.  Some triggers need to avoid being invoked while
1767 *      an event is currently in the process of being logged, since
1768 *      the trigger may itself log data into the trace buffer.  Thus
1769 *      we make sure the current event is committed before invoking
1770 *      those triggers.  To do that, the trigger invocation is split
1771 *      in two - the first part checks the filter using the current
1772 *      trace record; if a command has the @post_trigger flag set, it
1773 *      sets a bit for itself in the return value, otherwise it
1774 *      directly invokes the trigger.  Once all commands have been
1775 *      either invoked or set their return flag, the current record is
1776 *      either committed or discarded.  At that point, if any commands
1777 *      have deferred their triggers, those commands are finally
1778 *      invoked following the close of the current event.  In other
1779 *      words, if the event_trigger_ops @func() probe implementation
1780 *      itself logs to the trace buffer, this flag should be set,
1781 *      otherwise it can be left unspecified.
1782 *
1783 * @NEEDS_REC: A flag that says whether or not this command needs
1784 *      access to the trace record in order to perform its function,
1785 *      regardless of whether or not it has a filter associated with
1786 *      it (filters make a trigger require access to the trace record
1787 *      but are not always present).
1788 */
1789enum event_command_flags {
1790        EVENT_CMD_FL_POST_TRIGGER       = 1,
1791        EVENT_CMD_FL_NEEDS_REC          = 2,
1792};
1793
1794static inline bool event_command_post_trigger(struct event_command *cmd_ops)
1795{
1796        return cmd_ops->flags & EVENT_CMD_FL_POST_TRIGGER;
1797}
1798
1799static inline bool event_command_needs_rec(struct event_command *cmd_ops)
1800{
1801        return cmd_ops->flags & EVENT_CMD_FL_NEEDS_REC;
1802}
1803
1804extern int trace_event_enable_disable(struct trace_event_file *file,
1805                                      int enable, int soft_disable);
1806extern int tracing_alloc_snapshot(void);
1807extern void tracing_snapshot_cond(struct trace_array *tr, void *cond_data);
1808extern int tracing_snapshot_cond_enable(struct trace_array *tr, void *cond_data, cond_update_fn_t update);
1809
1810extern int tracing_snapshot_cond_disable(struct trace_array *tr);
1811extern void *tracing_cond_snapshot_data(struct trace_array *tr);
1812
1813extern const char *__start___trace_bprintk_fmt[];
1814extern const char *__stop___trace_bprintk_fmt[];
1815
1816extern const char *__start___tracepoint_str[];
1817extern const char *__stop___tracepoint_str[];
1818
1819void trace_printk_control(bool enabled);
1820void trace_printk_start_comm(void);
1821int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set);
1822int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled);
1823
1824/* Used from boot time tracer */
1825extern int trace_set_options(struct trace_array *tr, char *option);
1826extern int tracing_set_tracer(struct trace_array *tr, const char *buf);
1827extern ssize_t tracing_resize_ring_buffer(struct trace_array *tr,
1828                                          unsigned long size, int cpu_id);
1829extern int tracing_set_cpumask(struct trace_array *tr,
1830                                cpumask_var_t tracing_cpumask_new);
1831
1832
1833#define MAX_EVENT_NAME_LEN      64
1834
1835extern ssize_t trace_parse_run_command(struct file *file,
1836                const char __user *buffer, size_t count, loff_t *ppos,
1837                int (*createfn)(const char *));
1838
1839extern unsigned int err_pos(char *cmd, const char *str);
1840extern void tracing_log_err(struct trace_array *tr,
1841                            const char *loc, const char *cmd,
1842                            const char **errs, u8 type, u8 pos);
1843
1844/*
1845 * Normal trace_printk() and friends allocates special buffers
1846 * to do the manipulation, as well as saves the print formats
1847 * into sections to display. But the trace infrastructure wants
1848 * to use these without the added overhead at the price of being
1849 * a bit slower (used mainly for warnings, where we don't care
1850 * about performance). The internal_trace_puts() is for such
1851 * a purpose.
1852 */
1853#define internal_trace_puts(str) __trace_puts(_THIS_IP_, str, strlen(str))
1854
1855#undef FTRACE_ENTRY
1856#define FTRACE_ENTRY(call, struct_name, id, tstruct, print)     \
1857        extern struct trace_event_call                                  \
1858        __aligned(4) event_##call;
1859#undef FTRACE_ENTRY_DUP
1860#define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print) \
1861        FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
1862#undef FTRACE_ENTRY_PACKED
1863#define FTRACE_ENTRY_PACKED(call, struct_name, id, tstruct, print) \
1864        FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
1865
1866#include "trace_entries.h"
1867
1868#if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER)
1869int perf_ftrace_event_register(struct trace_event_call *call,
1870                               enum trace_reg type, void *data);
1871#else
1872#define perf_ftrace_event_register NULL
1873#endif
1874
1875#ifdef CONFIG_FTRACE_SYSCALLS
1876void init_ftrace_syscalls(void);
1877const char *get_syscall_name(int syscall);
1878#else
1879static inline void init_ftrace_syscalls(void) { }
1880static inline const char *get_syscall_name(int syscall)
1881{
1882        return NULL;
1883}
1884#endif
1885
1886#ifdef CONFIG_EVENT_TRACING
1887void trace_event_init(void);
1888void trace_event_eval_update(struct trace_eval_map **map, int len);
1889/* Used from boot time tracer */
1890extern int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set);
1891extern int trigger_process_regex(struct trace_event_file *file, char *buff);
1892#else
1893static inline void __init trace_event_init(void) { }
1894static inline void trace_event_eval_update(struct trace_eval_map **map, int len) { }
1895#endif
1896
1897#ifdef CONFIG_TRACER_SNAPSHOT
1898void tracing_snapshot_instance(struct trace_array *tr);
1899int tracing_alloc_snapshot_instance(struct trace_array *tr);
1900#else
1901static inline void tracing_snapshot_instance(struct trace_array *tr) { }
1902static inline int tracing_alloc_snapshot_instance(struct trace_array *tr)
1903{
1904        return 0;
1905}
1906#endif
1907
1908#ifdef CONFIG_PREEMPT_TRACER
1909void tracer_preempt_on(unsigned long a0, unsigned long a1);
1910void tracer_preempt_off(unsigned long a0, unsigned long a1);
1911#else
1912static inline void tracer_preempt_on(unsigned long a0, unsigned long a1) { }
1913static inline void tracer_preempt_off(unsigned long a0, unsigned long a1) { }
1914#endif
1915#ifdef CONFIG_IRQSOFF_TRACER
1916void tracer_hardirqs_on(unsigned long a0, unsigned long a1);
1917void tracer_hardirqs_off(unsigned long a0, unsigned long a1);
1918#else
1919static inline void tracer_hardirqs_on(unsigned long a0, unsigned long a1) { }
1920static inline void tracer_hardirqs_off(unsigned long a0, unsigned long a1) { }
1921#endif
1922
1923extern struct trace_iterator *tracepoint_print_iter;
1924
1925/*
1926 * Reset the state of the trace_iterator so that it can read consumed data.
1927 * Normally, the trace_iterator is used for reading the data when it is not
1928 * consumed, and must retain state.
1929 */
1930static __always_inline void trace_iterator_reset(struct trace_iterator *iter)
1931{
1932        const size_t offset = offsetof(struct trace_iterator, seq);
1933
1934        /*
1935         * Keep gcc from complaining about overwriting more than just one
1936         * member in the structure.
1937         */
1938        memset((char *)iter + offset, 0, sizeof(struct trace_iterator) - offset);
1939
1940        iter->pos = -1;
1941}
1942
1943/* Check the name is good for event/group/fields */
1944static inline bool is_good_name(const char *name)
1945{
1946        if (!isalpha(*name) && *name != '_')
1947                return false;
1948        while (*++name != '\0') {
1949                if (!isalpha(*name) && !isdigit(*name) && *name != '_')
1950                        return false;
1951        }
1952        return true;
1953}
1954
1955#endif /* _LINUX_KERNEL_TRACE_H */
1956