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
  49        __TRACE_LAST_TYPE,
  50};
  51
  52
  53#undef __field
  54#define __field(type, item)             type    item;
  55
  56#undef __field_fn
  57#define __field_fn(type, item)          type    item;
  58
  59#undef __field_struct
  60#define __field_struct(type, item)      __field(type, item)
  61
  62#undef __field_desc
  63#define __field_desc(type, container, item)
  64
  65#undef __field_packed
  66#define __field_packed(type, container, item)
  67
  68#undef __array
  69#define __array(type, item, size)       type    item[size];
  70
  71#undef __array_desc
  72#define __array_desc(type, container, item, size)
  73
  74#undef __dynamic_array
  75#define __dynamic_array(type, item)     type    item[];
  76
  77#undef F_STRUCT
  78#define F_STRUCT(args...)               args
  79
  80#undef FTRACE_ENTRY
  81#define FTRACE_ENTRY(name, struct_name, id, tstruct, print)             \
  82        struct struct_name {                                            \
  83                struct trace_entry      ent;                            \
  84                tstruct                                                 \
  85        }
  86
  87#undef FTRACE_ENTRY_DUP
  88#define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk)
  89
  90#undef FTRACE_ENTRY_REG
  91#define FTRACE_ENTRY_REG(name, struct_name, id, tstruct, print, regfn)  \
  92        FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print))
  93
  94#undef FTRACE_ENTRY_PACKED
  95#define FTRACE_ENTRY_PACKED(name, struct_name, id, tstruct, print)      \
  96        FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print)) __packed
  97
  98#include "trace_entries.h"
  99
 100/* Use this for memory failure errors */
 101#define MEM_FAIL(condition, fmt, ...) ({                        \
 102        static bool __section(".data.once") __warned;           \
 103        int __ret_warn_once = !!(condition);                    \
 104                                                                \
 105        if (unlikely(__ret_warn_once && !__warned)) {           \
 106                __warned = true;                                \
 107                pr_err("ERROR: " fmt, ##__VA_ARGS__);           \
 108        }                                                       \
 109        unlikely(__ret_warn_once);                              \
 110})
 111
 112/*
 113 * syscalls are special, and need special handling, this is why
 114 * they are not included in trace_entries.h
 115 */
 116struct syscall_trace_enter {
 117        struct trace_entry      ent;
 118        int                     nr;
 119        unsigned long           args[];
 120};
 121
 122struct syscall_trace_exit {
 123        struct trace_entry      ent;
 124        int                     nr;
 125        long                    ret;
 126};
 127
 128struct kprobe_trace_entry_head {
 129        struct trace_entry      ent;
 130        unsigned long           ip;
 131};
 132
 133struct kretprobe_trace_entry_head {
 134        struct trace_entry      ent;
 135        unsigned long           func;
 136        unsigned long           ret_ip;
 137};
 138
 139/*
 140 * trace_flag_type is an enumeration that holds different
 141 * states when a trace occurs. These are:
 142 *  IRQS_OFF            - interrupts were disabled
 143 *  IRQS_NOSUPPORT      - arch does not support irqs_disabled_flags
 144 *  NEED_RESCHED        - reschedule is requested
 145 *  HARDIRQ             - inside an interrupt handler
 146 *  SOFTIRQ             - inside a softirq handler
 147 */
 148enum trace_flag_type {
 149        TRACE_FLAG_IRQS_OFF             = 0x01,
 150        TRACE_FLAG_IRQS_NOSUPPORT       = 0x02,
 151        TRACE_FLAG_NEED_RESCHED         = 0x04,
 152        TRACE_FLAG_HARDIRQ              = 0x08,
 153        TRACE_FLAG_SOFTIRQ              = 0x10,
 154        TRACE_FLAG_PREEMPT_RESCHED      = 0x20,
 155        TRACE_FLAG_NMI                  = 0x40,
 156};
 157
 158#define TRACE_BUF_SIZE          1024
 159
 160struct trace_array;
 161
 162/*
 163 * The CPU trace array - it consists of thousands of trace entries
 164 * plus some other descriptor data: (for example which task started
 165 * the trace, etc.)
 166 */
 167struct trace_array_cpu {
 168        atomic_t                disabled;
 169        void                    *buffer_page;   /* ring buffer spare */
 170
 171        unsigned long           entries;
 172        unsigned long           saved_latency;
 173        unsigned long           critical_start;
 174        unsigned long           critical_end;
 175        unsigned long           critical_sequence;
 176        unsigned long           nice;
 177        unsigned long           policy;
 178        unsigned long           rt_priority;
 179        unsigned long           skipped_entries;
 180        u64                     preempt_timestamp;
 181        pid_t                   pid;
 182        kuid_t                  uid;
 183        char                    comm[TASK_COMM_LEN];
 184
 185#ifdef CONFIG_FUNCTION_TRACER
 186        int                     ftrace_ignore_pid;
 187#endif
 188        bool                    ignore_pid;
 189};
 190
 191struct tracer;
 192struct trace_option_dentry;
 193
 194struct array_buffer {
 195        struct trace_array              *tr;
 196        struct trace_buffer             *buffer;
 197        struct trace_array_cpu __percpu *data;
 198        u64                             time_start;
 199        int                             cpu;
 200};
 201
 202#define TRACE_FLAGS_MAX_SIZE            32
 203
 204struct trace_options {
 205        struct tracer                   *tracer;
 206        struct trace_option_dentry      *topts;
 207};
 208
 209struct trace_pid_list {
 210        int                             pid_max;
 211        unsigned long                   *pids;
 212};
 213
 214enum {
 215        TRACE_PIDS              = BIT(0),
 216        TRACE_NO_PIDS           = BIT(1),
 217};
 218
 219static inline bool pid_type_enabled(int type, struct trace_pid_list *pid_list,
 220                                    struct trace_pid_list *no_pid_list)
 221{
 222        /* Return true if the pid list in type has pids */
 223        return ((type & TRACE_PIDS) && pid_list) ||
 224                ((type & TRACE_NO_PIDS) && no_pid_list);
 225}
 226
 227static inline bool still_need_pid_events(int type, struct trace_pid_list *pid_list,
 228                                         struct trace_pid_list *no_pid_list)
 229{
 230        /*
 231         * Turning off what is in @type, return true if the "other"
 232         * pid list, still has pids in it.
 233         */
 234        return (!(type & TRACE_PIDS) && pid_list) ||
 235                (!(type & TRACE_NO_PIDS) && no_pid_list);
 236}
 237
 238typedef bool (*cond_update_fn_t)(struct trace_array *tr, void *cond_data);
 239
 240/**
 241 * struct cond_snapshot - conditional snapshot data and callback
 242 *
 243 * The cond_snapshot structure encapsulates a callback function and
 244 * data associated with the snapshot for a given tracing instance.
 245 *
 246 * When a snapshot is taken conditionally, by invoking
 247 * tracing_snapshot_cond(tr, cond_data), the cond_data passed in is
 248 * passed in turn to the cond_snapshot.update() function.  That data
 249 * can be compared by the update() implementation with the cond_data
 250 * contained within the struct cond_snapshot instance associated with
 251 * the trace_array.  Because the tr->max_lock is held throughout the
 252 * update() call, the update() function can directly retrieve the
 253 * cond_snapshot and cond_data associated with the per-instance
 254 * snapshot associated with the trace_array.
 255 *
 256 * The cond_snapshot.update() implementation can save data to be
 257 * associated with the snapshot if it decides to, and returns 'true'
 258 * in that case, or it returns 'false' if the conditional snapshot
 259 * shouldn't be taken.
 260 *
 261 * The cond_snapshot instance is created and associated with the
 262 * user-defined cond_data by tracing_cond_snapshot_enable().
 263 * Likewise, the cond_snapshot instance is destroyed and is no longer
 264 * associated with the trace instance by
 265 * tracing_cond_snapshot_disable().
 266 *
 267 * The method below is required.
 268 *
 269 * @update: When a conditional snapshot is invoked, the update()
 270 *      callback function is invoked with the tr->max_lock held.  The
 271 *      update() implementation signals whether or not to actually
 272 *      take the snapshot, by returning 'true' if so, 'false' if no
 273 *      snapshot should be taken.  Because the max_lock is held for
 274 *      the duration of update(), the implementation is safe to
 275 *      directly retrieved and save any implementation data it needs
 276 *      to in association with the snapshot.
 277 */
 278struct cond_snapshot {
 279        void                            *cond_data;
 280        cond_update_fn_t                update;
 281};
 282
 283/*
 284 * The trace array - an array of per-CPU trace arrays. This is the
 285 * highest level data structure that individual tracers deal with.
 286 * They have on/off state as well:
 287 */
 288struct trace_array {
 289        struct list_head        list;
 290        char                    *name;
 291        struct array_buffer     array_buffer;
 292#ifdef CONFIG_TRACER_MAX_TRACE
 293        /*
 294         * The max_buffer is used to snapshot the trace when a maximum
 295         * latency is reached, or when the user initiates a snapshot.
 296         * Some tracers will use this to store a maximum trace while
 297         * it continues examining live traces.
 298         *
 299         * The buffers for the max_buffer are set up the same as the array_buffer
 300         * When a snapshot is taken, the buffer of the max_buffer is swapped
 301         * with the buffer of the array_buffer and the buffers are reset for
 302         * the array_buffer so the tracing can continue.
 303         */
 304        struct array_buffer     max_buffer;
 305        bool                    allocated_snapshot;
 306#endif
 307#if defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER)
 308        unsigned long           max_latency;
 309#ifdef CONFIG_FSNOTIFY
 310        struct dentry           *d_max_latency;
 311        struct work_struct      fsnotify_work;
 312        struct irq_work         fsnotify_irqwork;
 313#endif
 314#endif
 315        struct trace_pid_list   __rcu *filtered_pids;
 316        struct trace_pid_list   __rcu *filtered_no_pids;
 317        /*
 318         * max_lock is used to protect the swapping of buffers
 319         * when taking a max snapshot. The buffers themselves are
 320         * protected by per_cpu spinlocks. But the action of the swap
 321         * needs its own lock.
 322         *
 323         * This is defined as a arch_spinlock_t in order to help
 324         * with performance when lockdep debugging is enabled.
 325         *
 326         * It is also used in other places outside the update_max_tr
 327         * so it needs to be defined outside of the
 328         * CONFIG_TRACER_MAX_TRACE.
 329         */
 330        arch_spinlock_t         max_lock;
 331        int                     buffer_disabled;
 332#ifdef CONFIG_FTRACE_SYSCALLS
 333        int                     sys_refcount_enter;
 334        int                     sys_refcount_exit;
 335        struct trace_event_file __rcu *enter_syscall_files[NR_syscalls];
 336        struct trace_event_file __rcu *exit_syscall_files[NR_syscalls];
 337#endif
 338        int                     stop_count;
 339        int                     clock_id;
 340        int                     nr_topts;
 341        bool                    clear_trace;
 342        int                     buffer_percent;
 343        unsigned int            n_err_log_entries;
 344        struct tracer           *current_trace;
 345        unsigned int            trace_flags;
 346        unsigned char           trace_flags_index[TRACE_FLAGS_MAX_SIZE];
 347        unsigned int            flags;
 348        raw_spinlock_t          start_lock;
 349        struct list_head        err_log;
 350        struct dentry           *dir;
 351        struct dentry           *options;
 352        struct dentry           *percpu_dir;
 353        struct dentry           *event_dir;
 354        struct trace_options    *topts;
 355        struct list_head        systems;
 356        struct list_head        events;
 357        struct trace_event_file *trace_marker_file;
 358        cpumask_var_t           tracing_cpumask; /* only trace on set CPUs */
 359        int                     ref;
 360        int                     trace_ref;
 361#ifdef CONFIG_FUNCTION_TRACER
 362        struct ftrace_ops       *ops;
 363        struct trace_pid_list   __rcu *function_pids;
 364        struct trace_pid_list   __rcu *function_no_pids;
 365#ifdef CONFIG_DYNAMIC_FTRACE
 366        /* All of these are protected by the ftrace_lock */
 367        struct list_head        func_probes;
 368        struct list_head        mod_trace;
 369        struct list_head        mod_notrace;
 370#endif
 371        /* function tracing enabled */
 372        int                     function_enabled;
 373#endif
 374        int                     time_stamp_abs_ref;
 375        struct list_head        hist_vars;
 376#ifdef CONFIG_TRACER_SNAPSHOT
 377        struct cond_snapshot    *cond_snapshot;
 378#endif
 379};
 380
 381enum {
 382        TRACE_ARRAY_FL_GLOBAL   = (1 << 0)
 383};
 384
 385extern struct list_head ftrace_trace_arrays;
 386
 387extern struct mutex trace_types_lock;
 388
 389extern int trace_array_get(struct trace_array *tr);
 390extern int tracing_check_open_get_tr(struct trace_array *tr);
 391extern struct trace_array *trace_array_find(const char *instance);
 392extern struct trace_array *trace_array_find_get(const char *instance);
 393
 394extern int tracing_set_time_stamp_abs(struct trace_array *tr, bool abs);
 395extern int tracing_set_clock(struct trace_array *tr, const char *clockstr);
 396
 397extern bool trace_clock_in_ns(struct trace_array *tr);
 398
 399/*
 400 * The global tracer (top) should be the first trace array added,
 401 * but we check the flag anyway.
 402 */
 403static inline struct trace_array *top_trace_array(void)
 404{
 405        struct trace_array *tr;
 406
 407        if (list_empty(&ftrace_trace_arrays))
 408                return NULL;
 409
 410        tr = list_entry(ftrace_trace_arrays.prev,
 411                        typeof(*tr), list);
 412        WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL));
 413        return tr;
 414}
 415
 416#define FTRACE_CMP_TYPE(var, type) \
 417        __builtin_types_compatible_p(typeof(var), type *)
 418
 419#undef IF_ASSIGN
 420#define IF_ASSIGN(var, entry, etype, id)                        \
 421        if (FTRACE_CMP_TYPE(var, etype)) {                      \
 422                var = (typeof(var))(entry);                     \
 423                WARN_ON(id != 0 && (entry)->type != id);        \
 424                break;                                          \
 425        }
 426
 427/* Will cause compile errors if type is not found. */
 428extern void __ftrace_bad_type(void);
 429
 430/*
 431 * The trace_assign_type is a verifier that the entry type is
 432 * the same as the type being assigned. To add new types simply
 433 * add a line with the following format:
 434 *
 435 * IF_ASSIGN(var, ent, type, id);
 436 *
 437 *  Where "type" is the trace type that includes the trace_entry
 438 *  as the "ent" item. And "id" is the trace identifier that is
 439 *  used in the trace_type enum.
 440 *
 441 *  If the type can have more than one id, then use zero.
 442 */
 443#define trace_assign_type(var, ent)                                     \
 444        do {                                                            \
 445                IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN);     \
 446                IF_ASSIGN(var, ent, struct ctx_switch_entry, 0);        \
 447                IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK);   \
 448                IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
 449                IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT);   \
 450                IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT); \
 451                IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS);   \
 452                IF_ASSIGN(var, ent, struct hwlat_entry, TRACE_HWLAT);   \
 453                IF_ASSIGN(var, ent, struct raw_data_entry, TRACE_RAW_DATA);\
 454                IF_ASSIGN(var, ent, struct trace_mmiotrace_rw,          \
 455                          TRACE_MMIO_RW);                               \
 456                IF_ASSIGN(var, ent, struct trace_mmiotrace_map,         \
 457                          TRACE_MMIO_MAP);                              \
 458                IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
 459                IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry,      \
 460                          TRACE_GRAPH_ENT);             \
 461                IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry,      \
 462                          TRACE_GRAPH_RET);             \
 463                __ftrace_bad_type();                                    \
 464        } while (0)
 465
 466/*
 467 * An option specific to a tracer. This is a boolean value.
 468 * The bit is the bit index that sets its value on the
 469 * flags value in struct tracer_flags.
 470 */
 471struct tracer_opt {
 472        const char      *name; /* Will appear on the trace_options file */
 473        u32             bit; /* Mask assigned in val field in tracer_flags */
 474};
 475
 476/*
 477 * The set of specific options for a tracer. Your tracer
 478 * have to set the initial value of the flags val.
 479 */
 480struct tracer_flags {
 481        u32                     val;
 482        struct tracer_opt       *opts;
 483        struct tracer           *trace;
 484};
 485
 486/* Makes more easy to define a tracer opt */
 487#define TRACER_OPT(s, b)        .name = #s, .bit = b
 488
 489
 490struct trace_option_dentry {
 491        struct tracer_opt               *opt;
 492        struct tracer_flags             *flags;
 493        struct trace_array              *tr;
 494        struct dentry                   *entry;
 495};
 496
 497/**
 498 * struct tracer - a specific tracer and its callbacks to interact with tracefs
 499 * @name: the name chosen to select it on the available_tracers file
 500 * @init: called when one switches to this tracer (echo name > current_tracer)
 501 * @reset: called when one switches to another tracer
 502 * @start: called when tracing is unpaused (echo 1 > tracing_on)
 503 * @stop: called when tracing is paused (echo 0 > tracing_on)
 504 * @update_thresh: called when tracing_thresh is updated
 505 * @open: called when the trace file is opened
 506 * @pipe_open: called when the trace_pipe file is opened
 507 * @close: called when the trace file is released
 508 * @pipe_close: called when the trace_pipe file is released
 509 * @read: override the default read callback on trace_pipe
 510 * @splice_read: override the default splice_read callback on trace_pipe
 511 * @selftest: selftest to run on boot (see trace_selftest.c)
 512 * @print_headers: override the first lines that describe your columns
 513 * @print_line: callback that prints a trace
 514 * @set_flag: signals one of your private flags changed (trace_options file)
 515 * @flags: your private flags
 516 */
 517struct tracer {
 518        const char              *name;
 519        int                     (*init)(struct trace_array *tr);
 520        void                    (*reset)(struct trace_array *tr);
 521        void                    (*start)(struct trace_array *tr);
 522        void                    (*stop)(struct trace_array *tr);
 523        int                     (*update_thresh)(struct trace_array *tr);
 524        void                    (*open)(struct trace_iterator *iter);
 525        void                    (*pipe_open)(struct trace_iterator *iter);
 526        void                    (*close)(struct trace_iterator *iter);
 527        void                    (*pipe_close)(struct trace_iterator *iter);
 528        ssize_t                 (*read)(struct trace_iterator *iter,
 529                                        struct file *filp, char __user *ubuf,
 530                                        size_t cnt, loff_t *ppos);
 531        ssize_t                 (*splice_read)(struct trace_iterator *iter,
 532                                               struct file *filp,
 533                                               loff_t *ppos,
 534                                               struct pipe_inode_info *pipe,
 535                                               size_t len,
 536                                               unsigned int flags);
 537#ifdef CONFIG_FTRACE_STARTUP_TEST
 538        int                     (*selftest)(struct tracer *trace,
 539                                            struct trace_array *tr);
 540#endif
 541        void                    (*print_header)(struct seq_file *m);
 542        enum print_line_t       (*print_line)(struct trace_iterator *iter);
 543        /* If you handled the flag setting, return 0 */
 544        int                     (*set_flag)(struct trace_array *tr,
 545                                            u32 old_flags, u32 bit, int set);
 546        /* Return 0 if OK with change, else return non-zero */
 547        int                     (*flag_changed)(struct trace_array *tr,
 548                                                u32 mask, int set);
 549        struct tracer           *next;
 550        struct tracer_flags     *flags;
 551        int                     enabled;
 552        bool                    print_max;
 553        bool                    allow_instances;
 554#ifdef CONFIG_TRACER_MAX_TRACE
 555        bool                    use_max_tr;
 556#endif
 557        /* True if tracer cannot be enabled in kernel param */
 558        bool                    noboot;
 559};
 560
 561static inline struct ring_buffer_iter *
 562trace_buffer_iter(struct trace_iterator *iter, int cpu)
 563{
 564        return iter->buffer_iter ? iter->buffer_iter[cpu] : NULL;
 565}
 566
 567int tracer_init(struct tracer *t, struct trace_array *tr);
 568int tracing_is_enabled(void);
 569void tracing_reset_online_cpus(struct array_buffer *buf);
 570void tracing_reset_current(int cpu);
 571void tracing_reset_all_online_cpus(void);
 572int tracing_open_generic(struct inode *inode, struct file *filp);
 573int tracing_open_generic_tr(struct inode *inode, struct file *filp);
 574bool tracing_is_disabled(void);
 575bool tracer_tracing_is_on(struct trace_array *tr);
 576void tracer_tracing_on(struct trace_array *tr);
 577void tracer_tracing_off(struct trace_array *tr);
 578struct dentry *trace_create_file(const char *name,
 579                                 umode_t mode,
 580                                 struct dentry *parent,
 581                                 void *data,
 582                                 const struct file_operations *fops);
 583
 584int tracing_init_dentry(void);
 585
 586struct ring_buffer_event;
 587
 588struct ring_buffer_event *
 589trace_buffer_lock_reserve(struct trace_buffer *buffer,
 590                          int type,
 591                          unsigned long len,
 592                          unsigned long flags,
 593                          int pc);
 594
 595struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
 596                                                struct trace_array_cpu *data);
 597
 598struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
 599                                          int *ent_cpu, u64 *ent_ts);
 600
 601void trace_buffer_unlock_commit_nostack(struct trace_buffer *buffer,
 602                                        struct ring_buffer_event *event);
 603
 604int trace_empty(struct trace_iterator *iter);
 605
 606void *trace_find_next_entry_inc(struct trace_iterator *iter);
 607
 608void trace_init_global_iter(struct trace_iterator *iter);
 609
 610void tracing_iter_reset(struct trace_iterator *iter, int cpu);
 611
 612unsigned long trace_total_entries_cpu(struct trace_array *tr, int cpu);
 613unsigned long trace_total_entries(struct trace_array *tr);
 614
 615void trace_function(struct trace_array *tr,
 616                    unsigned long ip,
 617                    unsigned long parent_ip,
 618                    unsigned long flags, int pc);
 619void trace_graph_function(struct trace_array *tr,
 620                    unsigned long ip,
 621                    unsigned long parent_ip,
 622                    unsigned long flags, int pc);
 623void trace_latency_header(struct seq_file *m);
 624void trace_default_header(struct seq_file *m);
 625void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
 626int trace_empty(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 long flags, int skip,
 691                   int pc);
 692#else
 693static inline void __trace_stack(struct trace_array *tr, unsigned long flags,
 694                                 int skip, int pc)
 695{
 696}
 697#endif /* CONFIG_STACKTRACE */
 698
 699extern u64 ftrace_now(int cpu);
 700
 701extern void trace_find_cmdline(int pid, char comm[]);
 702extern int trace_find_tgid(int pid);
 703extern void trace_event_follow_fork(struct trace_array *tr, bool enable);
 704
 705#ifdef CONFIG_DYNAMIC_FTRACE
 706extern unsigned long ftrace_update_tot_cnt;
 707extern unsigned long ftrace_number_of_pages;
 708extern unsigned long ftrace_number_of_groups;
 709void ftrace_init_trace_array(struct trace_array *tr);
 710#else
 711static inline void ftrace_init_trace_array(struct trace_array *tr) { }
 712#endif
 713#define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
 714extern int DYN_FTRACE_TEST_NAME(void);
 715#define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
 716extern int DYN_FTRACE_TEST_NAME2(void);
 717
 718extern bool ring_buffer_expanded;
 719extern bool tracing_selftest_disabled;
 720
 721#ifdef CONFIG_FTRACE_STARTUP_TEST
 722extern void __init disable_tracing_selftest(const char *reason);
 723
 724extern int trace_selftest_startup_function(struct tracer *trace,
 725                                           struct trace_array *tr);
 726extern int trace_selftest_startup_function_graph(struct tracer *trace,
 727                                                 struct trace_array *tr);
 728extern int trace_selftest_startup_irqsoff(struct tracer *trace,
 729                                          struct trace_array *tr);
 730extern int trace_selftest_startup_preemptoff(struct tracer *trace,
 731                                             struct trace_array *tr);
 732extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
 733                                                 struct trace_array *tr);
 734extern int trace_selftest_startup_wakeup(struct tracer *trace,
 735                                         struct trace_array *tr);
 736extern int trace_selftest_startup_nop(struct tracer *trace,
 737                                         struct trace_array *tr);
 738extern int trace_selftest_startup_branch(struct tracer *trace,
 739                                         struct trace_array *tr);
 740/*
 741 * Tracer data references selftest functions that only occur
 742 * on boot up. These can be __init functions. Thus, when selftests
 743 * are enabled, then the tracers need to reference __init functions.
 744 */
 745#define __tracer_data           __refdata
 746#else
 747static inline void __init disable_tracing_selftest(const char *reason)
 748{
 749}
 750/* Tracers are seldom changed. Optimize when selftests are disabled. */
 751#define __tracer_data           __read_mostly
 752#endif /* CONFIG_FTRACE_STARTUP_TEST */
 753
 754extern void *head_page(struct trace_array_cpu *data);
 755extern unsigned long long ns2usecs(u64 nsec);
 756extern int
 757trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
 758extern int
 759trace_vprintk(unsigned long ip, const char *fmt, va_list args);
 760extern int
 761trace_array_vprintk(struct trace_array *tr,
 762                    unsigned long ip, const char *fmt, va_list args);
 763int trace_array_printk_buf(struct trace_buffer *buffer,
 764                           unsigned long ip, const char *fmt, ...);
 765void trace_printk_seq(struct trace_seq *s);
 766enum print_line_t print_trace_line(struct trace_iterator *iter);
 767
 768extern char trace_find_mark(unsigned long long duration);
 769
 770struct ftrace_hash;
 771
 772struct ftrace_mod_load {
 773        struct list_head        list;
 774        char                    *func;
 775        char                    *module;
 776        int                      enable;
 777};
 778
 779enum {
 780        FTRACE_HASH_FL_MOD      = (1 << 0),
 781};
 782
 783struct ftrace_hash {
 784        unsigned long           size_bits;
 785        struct hlist_head       *buckets;
 786        unsigned long           count;
 787        unsigned long           flags;
 788        struct rcu_head         rcu;
 789};
 790
 791struct ftrace_func_entry *
 792ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip);
 793
 794static __always_inline bool ftrace_hash_empty(struct ftrace_hash *hash)
 795{
 796        return !hash || !(hash->count || (hash->flags & FTRACE_HASH_FL_MOD));
 797}
 798
 799/* Standard output formatting function used for function return traces */
 800#ifdef CONFIG_FUNCTION_GRAPH_TRACER
 801
 802/* Flag options */
 803#define TRACE_GRAPH_PRINT_OVERRUN       0x1
 804#define TRACE_GRAPH_PRINT_CPU           0x2
 805#define TRACE_GRAPH_PRINT_OVERHEAD      0x4
 806#define TRACE_GRAPH_PRINT_PROC          0x8
 807#define TRACE_GRAPH_PRINT_DURATION      0x10
 808#define TRACE_GRAPH_PRINT_ABS_TIME      0x20
 809#define TRACE_GRAPH_PRINT_REL_TIME      0x40
 810#define TRACE_GRAPH_PRINT_IRQS          0x80
 811#define TRACE_GRAPH_PRINT_TAIL          0x100
 812#define TRACE_GRAPH_SLEEP_TIME          0x200
 813#define TRACE_GRAPH_GRAPH_TIME          0x400
 814#define TRACE_GRAPH_PRINT_FILL_SHIFT    28
 815#define TRACE_GRAPH_PRINT_FILL_MASK     (0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT)
 816
 817extern void ftrace_graph_sleep_time_control(bool enable);
 818
 819#ifdef CONFIG_FUNCTION_PROFILER
 820extern void ftrace_graph_graph_time_control(bool enable);
 821#else
 822static inline void ftrace_graph_graph_time_control(bool enable) { }
 823#endif
 824
 825extern enum print_line_t
 826print_graph_function_flags(struct trace_iterator *iter, u32 flags);
 827extern void print_graph_headers_flags(struct seq_file *s, u32 flags);
 828extern void
 829trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
 830extern void graph_trace_open(struct trace_iterator *iter);
 831extern void graph_trace_close(struct trace_iterator *iter);
 832extern int __trace_graph_entry(struct trace_array *tr,
 833                               struct ftrace_graph_ent *trace,
 834                               unsigned long flags, int pc);
 835extern void __trace_graph_return(struct trace_array *tr,
 836                                 struct ftrace_graph_ret *trace,
 837                                 unsigned long flags, int pc);
 838
 839#ifdef CONFIG_DYNAMIC_FTRACE
 840extern struct ftrace_hash __rcu *ftrace_graph_hash;
 841extern struct ftrace_hash __rcu *ftrace_graph_notrace_hash;
 842
 843static inline int ftrace_graph_addr(struct ftrace_graph_ent *trace)
 844{
 845        unsigned long addr = trace->func;
 846        int ret = 0;
 847        struct ftrace_hash *hash;
 848
 849        preempt_disable_notrace();
 850
 851        /*
 852         * Have to open code "rcu_dereference_sched()" because the
 853         * function graph tracer can be called when RCU is not
 854         * "watching".
 855         * Protected with schedule_on_each_cpu(ftrace_sync)
 856         */
 857        hash = rcu_dereference_protected(ftrace_graph_hash, !preemptible());
 858
 859        if (ftrace_hash_empty(hash)) {
 860                ret = 1;
 861                goto out;
 862        }
 863
 864        if (ftrace_lookup_ip(hash, addr)) {
 865
 866                /*
 867                 * This needs to be cleared on the return functions
 868                 * when the depth is zero.
 869                 */
 870                trace_recursion_set(TRACE_GRAPH_BIT);
 871                trace_recursion_set_depth(trace->depth);
 872
 873                /*
 874                 * If no irqs are to be traced, but a set_graph_function
 875                 * is set, and called by an interrupt handler, we still
 876                 * want to trace it.
 877                 */
 878                if (in_irq())
 879                        trace_recursion_set(TRACE_IRQ_BIT);
 880                else
 881                        trace_recursion_clear(TRACE_IRQ_BIT);
 882                ret = 1;
 883        }
 884
 885out:
 886        preempt_enable_notrace();
 887        return ret;
 888}
 889
 890static inline void ftrace_graph_addr_finish(struct ftrace_graph_ret *trace)
 891{
 892        if (trace_recursion_test(TRACE_GRAPH_BIT) &&
 893            trace->depth == trace_recursion_depth())
 894                trace_recursion_clear(TRACE_GRAPH_BIT);
 895}
 896
 897static inline int ftrace_graph_notrace_addr(unsigned long addr)
 898{
 899        int ret = 0;
 900        struct ftrace_hash *notrace_hash;
 901
 902        preempt_disable_notrace();
 903
 904        /*
 905         * Have to open code "rcu_dereference_sched()" because the
 906         * function graph tracer can be called when RCU is not
 907         * "watching".
 908         * Protected with schedule_on_each_cpu(ftrace_sync)
 909         */
 910        notrace_hash = rcu_dereference_protected(ftrace_graph_notrace_hash,
 911                                                 !preemptible());
 912
 913        if (ftrace_lookup_ip(notrace_hash, addr))
 914                ret = 1;
 915
 916        preempt_enable_notrace();
 917        return ret;
 918}
 919#else
 920static inline int ftrace_graph_addr(struct ftrace_graph_ent *trace)
 921{
 922        return 1;
 923}
 924
 925static inline int ftrace_graph_notrace_addr(unsigned long addr)
 926{
 927        return 0;
 928}
 929static inline void ftrace_graph_addr_finish(struct ftrace_graph_ret *trace)
 930{ }
 931#endif /* CONFIG_DYNAMIC_FTRACE */
 932
 933extern unsigned int fgraph_max_depth;
 934
 935static inline bool ftrace_graph_ignore_func(struct ftrace_graph_ent *trace)
 936{
 937        /* trace it when it is-nested-in or is a function enabled. */
 938        return !(trace_recursion_test(TRACE_GRAPH_BIT) ||
 939                 ftrace_graph_addr(trace)) ||
 940                (trace->depth < 0) ||
 941                (fgraph_max_depth && trace->depth >= fgraph_max_depth);
 942}
 943
 944#else /* CONFIG_FUNCTION_GRAPH_TRACER */
 945static inline enum print_line_t
 946print_graph_function_flags(struct trace_iterator *iter, u32 flags)
 947{
 948        return TRACE_TYPE_UNHANDLED;
 949}
 950#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
 951
 952extern struct list_head ftrace_pids;
 953
 954#ifdef CONFIG_FUNCTION_TRACER
 955
 956#define FTRACE_PID_IGNORE       -1
 957#define FTRACE_PID_TRACE        -2
 958
 959struct ftrace_func_command {
 960        struct list_head        list;
 961        char                    *name;
 962        int                     (*func)(struct trace_array *tr,
 963                                        struct ftrace_hash *hash,
 964                                        char *func, char *cmd,
 965                                        char *params, int enable);
 966};
 967extern bool ftrace_filter_param __initdata;
 968static inline int ftrace_trace_task(struct trace_array *tr)
 969{
 970        return this_cpu_read(tr->array_buffer.data->ftrace_ignore_pid) !=
 971                FTRACE_PID_IGNORE;
 972}
 973extern int ftrace_is_dead(void);
 974int ftrace_create_function_files(struct trace_array *tr,
 975                                 struct dentry *parent);
 976void ftrace_destroy_function_files(struct trace_array *tr);
 977int ftrace_allocate_ftrace_ops(struct trace_array *tr);
 978void ftrace_free_ftrace_ops(struct trace_array *tr);
 979void ftrace_init_global_array_ops(struct trace_array *tr);
 980void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func);
 981void ftrace_reset_array_ops(struct trace_array *tr);
 982void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer);
 983void ftrace_init_tracefs_toplevel(struct trace_array *tr,
 984                                  struct dentry *d_tracer);
 985void ftrace_clear_pids(struct trace_array *tr);
 986int init_function_trace(void);
 987void ftrace_pid_follow_fork(struct trace_array *tr, bool enable);
 988#else
 989static inline int ftrace_trace_task(struct trace_array *tr)
 990{
 991        return 1;
 992}
 993static inline int ftrace_is_dead(void) { return 0; }
 994static inline int
 995ftrace_create_function_files(struct trace_array *tr,
 996                             struct dentry *parent)
 997{
 998        return 0;
 999}
1000static inline int ftrace_allocate_ftrace_ops(struct trace_array *tr)
1001{
1002        return 0;
1003}
1004static inline void ftrace_free_ftrace_ops(struct trace_array *tr) { }
1005static inline void ftrace_destroy_function_files(struct trace_array *tr) { }
1006static inline __init void
1007ftrace_init_global_array_ops(struct trace_array *tr) { }
1008static inline void ftrace_reset_array_ops(struct trace_array *tr) { }
1009static inline void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d) { }
1010static inline void ftrace_init_tracefs_toplevel(struct trace_array *tr, struct dentry *d) { }
1011static inline void ftrace_clear_pids(struct trace_array *tr) { }
1012static inline int init_function_trace(void) { return 0; }
1013static inline void ftrace_pid_follow_fork(struct trace_array *tr, bool enable) { }
1014/* ftace_func_t type is not defined, use macro instead of static inline */
1015#define ftrace_init_array_ops(tr, func) do { } while (0)
1016#endif /* CONFIG_FUNCTION_TRACER */
1017
1018#if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE)
1019
1020struct ftrace_probe_ops {
1021        void                    (*func)(unsigned long ip,
1022                                        unsigned long parent_ip,
1023                                        struct trace_array *tr,
1024                                        struct ftrace_probe_ops *ops,
1025                                        void *data);
1026        int                     (*init)(struct ftrace_probe_ops *ops,
1027                                        struct trace_array *tr,
1028                                        unsigned long ip, void *init_data,
1029                                        void **data);
1030        void                    (*free)(struct ftrace_probe_ops *ops,
1031                                        struct trace_array *tr,
1032                                        unsigned long ip, void *data);
1033        int                     (*print)(struct seq_file *m,
1034                                         unsigned long ip,
1035                                         struct ftrace_probe_ops *ops,
1036                                         void *data);
1037};
1038
1039struct ftrace_func_mapper;
1040typedef int (*ftrace_mapper_func)(void *data);
1041
1042struct ftrace_func_mapper *allocate_ftrace_func_mapper(void);
1043void **ftrace_func_mapper_find_ip(struct ftrace_func_mapper *mapper,
1044                                           unsigned long ip);
1045int ftrace_func_mapper_add_ip(struct ftrace_func_mapper *mapper,
1046                               unsigned long ip, void *data);
1047void *ftrace_func_mapper_remove_ip(struct ftrace_func_mapper *mapper,
1048                                   unsigned long ip);
1049void free_ftrace_func_mapper(struct ftrace_func_mapper *mapper,
1050                             ftrace_mapper_func free_func);
1051
1052extern int
1053register_ftrace_function_probe(char *glob, struct trace_array *tr,
1054                               struct ftrace_probe_ops *ops, void *data);
1055extern int
1056unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr,
1057                                      struct ftrace_probe_ops *ops);
1058extern void clear_ftrace_function_probes(struct trace_array *tr);
1059
1060int register_ftrace_command(struct ftrace_func_command *cmd);
1061int unregister_ftrace_command(struct ftrace_func_command *cmd);
1062
1063void ftrace_create_filter_files(struct ftrace_ops *ops,
1064                                struct dentry *parent);
1065void ftrace_destroy_filter_files(struct ftrace_ops *ops);
1066
1067extern int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf,
1068                             int len, int reset);
1069extern int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,
1070                              int len, int reset);
1071#else
1072struct ftrace_func_command;
1073
1074static inline __init int register_ftrace_command(struct ftrace_func_command *cmd)
1075{
1076        return -EINVAL;
1077}
1078static inline __init int unregister_ftrace_command(char *cmd_name)
1079{
1080        return -EINVAL;
1081}
1082static inline void clear_ftrace_function_probes(struct trace_array *tr)
1083{
1084}
1085
1086/*
1087 * The ops parameter passed in is usually undefined.
1088 * This must be a macro.
1089 */
1090#define ftrace_create_filter_files(ops, parent) do { } while (0)
1091#define ftrace_destroy_filter_files(ops) do { } while (0)
1092#endif /* CONFIG_FUNCTION_TRACER && CONFIG_DYNAMIC_FTRACE */
1093
1094bool ftrace_event_is_function(struct trace_event_call *call);
1095
1096/*
1097 * struct trace_parser - servers for reading the user input separated by spaces
1098 * @cont: set if the input is not complete - no final space char was found
1099 * @buffer: holds the parsed user input
1100 * @idx: user input length
1101 * @size: buffer size
1102 */
1103struct trace_parser {
1104        bool            cont;
1105        char            *buffer;
1106        unsigned        idx;
1107        unsigned        size;
1108};
1109
1110static inline bool trace_parser_loaded(struct trace_parser *parser)
1111{
1112        return (parser->idx != 0);
1113}
1114
1115static inline bool trace_parser_cont(struct trace_parser *parser)
1116{
1117        return parser->cont;
1118}
1119
1120static inline void trace_parser_clear(struct trace_parser *parser)
1121{
1122        parser->cont = false;
1123        parser->idx = 0;
1124}
1125
1126extern int trace_parser_get_init(struct trace_parser *parser, int size);
1127extern void trace_parser_put(struct trace_parser *parser);
1128extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
1129        size_t cnt, loff_t *ppos);
1130
1131/*
1132 * Only create function graph options if function graph is configured.
1133 */
1134#ifdef CONFIG_FUNCTION_GRAPH_TRACER
1135# define FGRAPH_FLAGS                                           \
1136                C(DISPLAY_GRAPH,        "display-graph"),
1137#else
1138# define FGRAPH_FLAGS
1139#endif
1140
1141#ifdef CONFIG_BRANCH_TRACER
1142# define BRANCH_FLAGS                                   \
1143                C(BRANCH,               "branch"),
1144#else
1145# define BRANCH_FLAGS
1146#endif
1147
1148#ifdef CONFIG_FUNCTION_TRACER
1149# define FUNCTION_FLAGS                                         \
1150                C(FUNCTION,             "function-trace"),      \
1151                C(FUNC_FORK,            "function-fork"),
1152# define FUNCTION_DEFAULT_FLAGS         TRACE_ITER_FUNCTION
1153#else
1154# define FUNCTION_FLAGS
1155# define FUNCTION_DEFAULT_FLAGS         0UL
1156# define TRACE_ITER_FUNC_FORK           0UL
1157#endif
1158
1159#ifdef CONFIG_STACKTRACE
1160# define STACK_FLAGS                            \
1161                C(STACKTRACE,           "stacktrace"),
1162#else
1163# define STACK_FLAGS
1164#endif
1165
1166/*
1167 * trace_iterator_flags is an enumeration that defines bit
1168 * positions into trace_flags that controls the output.
1169 *
1170 * NOTE: These bits must match the trace_options array in
1171 *       trace.c (this macro guarantees it).
1172 */
1173#define TRACE_FLAGS                                             \
1174                C(PRINT_PARENT,         "print-parent"),        \
1175                C(SYM_OFFSET,           "sym-offset"),          \
1176                C(SYM_ADDR,             "sym-addr"),            \
1177                C(VERBOSE,              "verbose"),             \
1178                C(RAW,                  "raw"),                 \
1179                C(HEX,                  "hex"),                 \
1180                C(BIN,                  "bin"),                 \
1181                C(BLOCK,                "block"),               \
1182                C(PRINTK,               "trace_printk"),        \
1183                C(ANNOTATE,             "annotate"),            \
1184                C(USERSTACKTRACE,       "userstacktrace"),      \
1185                C(SYM_USEROBJ,          "sym-userobj"),         \
1186                C(PRINTK_MSGONLY,       "printk-msg-only"),     \
1187                C(CONTEXT_INFO,         "context-info"),   /* Print pid/cpu/time */ \
1188                C(LATENCY_FMT,          "latency-format"),      \
1189                C(RECORD_CMD,           "record-cmd"),          \
1190                C(RECORD_TGID,          "record-tgid"),         \
1191                C(OVERWRITE,            "overwrite"),           \
1192                C(STOP_ON_FREE,         "disable_on_free"),     \
1193                C(IRQ_INFO,             "irq-info"),            \
1194                C(MARKERS,              "markers"),             \
1195                C(EVENT_FORK,           "event-fork"),          \
1196                C(PAUSE_ON_TRACE,       "pause-on-trace"),      \
1197                FUNCTION_FLAGS                                  \
1198                FGRAPH_FLAGS                                    \
1199                STACK_FLAGS                                     \
1200                BRANCH_FLAGS
1201
1202/*
1203 * By defining C, we can make TRACE_FLAGS a list of bit names
1204 * that will define the bits for the flag masks.
1205 */
1206#undef C
1207#define C(a, b) TRACE_ITER_##a##_BIT
1208
1209enum trace_iterator_bits {
1210        TRACE_FLAGS
1211        /* Make sure we don't go more than we have bits for */
1212        TRACE_ITER_LAST_BIT
1213};
1214
1215/*
1216 * By redefining C, we can make TRACE_FLAGS a list of masks that
1217 * use the bits as defined above.
1218 */
1219#undef C
1220#define C(a, b) TRACE_ITER_##a = (1 << TRACE_ITER_##a##_BIT)
1221
1222enum trace_iterator_flags { TRACE_FLAGS };
1223
1224/*
1225 * TRACE_ITER_SYM_MASK masks the options in trace_flags that
1226 * control the output of kernel symbols.
1227 */
1228#define TRACE_ITER_SYM_MASK \
1229        (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
1230
1231extern struct tracer nop_trace;
1232
1233#ifdef CONFIG_BRANCH_TRACER
1234extern int enable_branch_tracing(struct trace_array *tr);
1235extern void disable_branch_tracing(void);
1236static inline int trace_branch_enable(struct trace_array *tr)
1237{
1238        if (tr->trace_flags & TRACE_ITER_BRANCH)
1239                return enable_branch_tracing(tr);
1240        return 0;
1241}
1242static inline void trace_branch_disable(void)
1243{
1244        /* due to races, always disable */
1245        disable_branch_tracing();
1246}
1247#else
1248static inline int trace_branch_enable(struct trace_array *tr)
1249{
1250        return 0;
1251}
1252static inline void trace_branch_disable(void)
1253{
1254}
1255#endif /* CONFIG_BRANCH_TRACER */
1256
1257/* set ring buffers to default size if not already done so */
1258int tracing_update_buffers(void);
1259
1260struct ftrace_event_field {
1261        struct list_head        link;
1262        const char              *name;
1263        const char              *type;
1264        int                     filter_type;
1265        int                     offset;
1266        int                     size;
1267        int                     is_signed;
1268};
1269
1270struct prog_entry;
1271
1272struct event_filter {
1273        struct prog_entry __rcu *prog;
1274        char                    *filter_string;
1275};
1276
1277struct event_subsystem {
1278        struct list_head        list;
1279        const char              *name;
1280        struct event_filter     *filter;
1281        int                     ref_count;
1282};
1283
1284struct trace_subsystem_dir {
1285        struct list_head                list;
1286        struct event_subsystem          *subsystem;
1287        struct trace_array              *tr;
1288        struct dentry                   *entry;
1289        int                             ref_count;
1290        int                             nr_events;
1291};
1292
1293extern int call_filter_check_discard(struct trace_event_call *call, void *rec,
1294                                     struct trace_buffer *buffer,
1295                                     struct ring_buffer_event *event);
1296
1297void trace_buffer_unlock_commit_regs(struct trace_array *tr,
1298                                     struct trace_buffer *buffer,
1299                                     struct ring_buffer_event *event,
1300                                     unsigned long flags, int pc,
1301                                     struct pt_regs *regs);
1302
1303static inline void trace_buffer_unlock_commit(struct trace_array *tr,
1304                                              struct trace_buffer *buffer,
1305                                              struct ring_buffer_event *event,
1306                                              unsigned long flags, int pc)
1307{
1308        trace_buffer_unlock_commit_regs(tr, buffer, event, flags, pc, NULL);
1309}
1310
1311DECLARE_PER_CPU(struct ring_buffer_event *, trace_buffered_event);
1312DECLARE_PER_CPU(int, trace_buffered_event_cnt);
1313void trace_buffered_event_disable(void);
1314void trace_buffered_event_enable(void);
1315
1316static inline void
1317__trace_event_discard_commit(struct trace_buffer *buffer,
1318                             struct ring_buffer_event *event)
1319{
1320        if (this_cpu_read(trace_buffered_event) == event) {
1321                /* Simply release the temp buffer */
1322                this_cpu_dec(trace_buffered_event_cnt);
1323                return;
1324        }
1325        ring_buffer_discard_commit(buffer, event);
1326}
1327
1328/*
1329 * Helper function for event_trigger_unlock_commit{_regs}().
1330 * If there are event triggers attached to this event that requires
1331 * filtering against its fields, then they will be called as the
1332 * entry already holds the field information of the current event.
1333 *
1334 * It also checks if the event should be discarded or not.
1335 * It is to be discarded if the event is soft disabled and the
1336 * event was only recorded to process triggers, or if the event
1337 * filter is active and this event did not match the filters.
1338 *
1339 * Returns true if the event is discarded, false otherwise.
1340 */
1341static inline bool
1342__event_trigger_test_discard(struct trace_event_file *file,
1343                             struct trace_buffer *buffer,
1344                             struct ring_buffer_event *event,
1345                             void *entry,
1346                             enum event_trigger_type *tt)
1347{
1348        unsigned long eflags = file->flags;
1349
1350        if (eflags & EVENT_FILE_FL_TRIGGER_COND)
1351                *tt = event_triggers_call(file, entry, event);
1352
1353        if (test_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &file->flags) ||
1354            (unlikely(file->flags & EVENT_FILE_FL_FILTERED) &&
1355             !filter_match_preds(file->filter, entry))) {
1356                __trace_event_discard_commit(buffer, event);
1357                return true;
1358        }
1359
1360        return false;
1361}
1362
1363/**
1364 * event_trigger_unlock_commit - handle triggers and finish event commit
1365 * @file: The file pointer assoctiated to the event
1366 * @buffer: The ring buffer that the event is being written to
1367 * @event: The event meta data in the ring buffer
1368 * @entry: The event itself
1369 * @irq_flags: The state of the interrupts at the start of the event
1370 * @pc: The state of the preempt count at the start of the event.
1371 *
1372 * This is a helper function to handle triggers that require data
1373 * from the event itself. It also tests the event against filters and
1374 * if the event is soft disabled and should be discarded.
1375 */
1376static inline void
1377event_trigger_unlock_commit(struct trace_event_file *file,
1378                            struct trace_buffer *buffer,
1379                            struct ring_buffer_event *event,
1380                            void *entry, unsigned long irq_flags, int pc)
1381{
1382        enum event_trigger_type tt = ETT_NONE;
1383
1384        if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
1385                trace_buffer_unlock_commit(file->tr, buffer, event, irq_flags, pc);
1386
1387        if (tt)
1388                event_triggers_post_call(file, tt);
1389}
1390
1391/**
1392 * event_trigger_unlock_commit_regs - handle triggers and finish event commit
1393 * @file: The file pointer assoctiated to the event
1394 * @buffer: The ring buffer that the event is being written to
1395 * @event: The event meta data in the ring buffer
1396 * @entry: The event itself
1397 * @irq_flags: The state of the interrupts at the start of the event
1398 * @pc: The state of the preempt count at the start of the event.
1399 *
1400 * This is a helper function to handle triggers that require data
1401 * from the event itself. It also tests the event against filters and
1402 * if the event is soft disabled and should be discarded.
1403 *
1404 * Same as event_trigger_unlock_commit() but calls
1405 * trace_buffer_unlock_commit_regs() instead of trace_buffer_unlock_commit().
1406 */
1407static inline void
1408event_trigger_unlock_commit_regs(struct trace_event_file *file,
1409                                 struct trace_buffer *buffer,
1410                                 struct ring_buffer_event *event,
1411                                 void *entry, unsigned long irq_flags, int pc,
1412                                 struct pt_regs *regs)
1413{
1414        enum event_trigger_type tt = ETT_NONE;
1415
1416        if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
1417                trace_buffer_unlock_commit_regs(file->tr, buffer, event,
1418                                                irq_flags, pc, regs);
1419
1420        if (tt)
1421                event_triggers_post_call(file, tt);
1422}
1423
1424#define FILTER_PRED_INVALID     ((unsigned short)-1)
1425#define FILTER_PRED_IS_RIGHT    (1 << 15)
1426#define FILTER_PRED_FOLD        (1 << 15)
1427
1428/*
1429 * The max preds is the size of unsigned short with
1430 * two flags at the MSBs. One bit is used for both the IS_RIGHT
1431 * and FOLD flags. The other is reserved.
1432 *
1433 * 2^14 preds is way more than enough.
1434 */
1435#define MAX_FILTER_PRED         16384
1436
1437struct filter_pred;
1438struct regex;
1439
1440typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event);
1441
1442typedef int (*regex_match_func)(char *str, struct regex *r, int len);
1443
1444enum regex_type {
1445        MATCH_FULL = 0,
1446        MATCH_FRONT_ONLY,
1447        MATCH_MIDDLE_ONLY,
1448        MATCH_END_ONLY,
1449        MATCH_GLOB,
1450        MATCH_INDEX,
1451};
1452
1453struct regex {
1454        char                    pattern[MAX_FILTER_STR_VAL];
1455        int                     len;
1456        int                     field_len;
1457        regex_match_func        match;
1458};
1459
1460struct filter_pred {
1461        filter_pred_fn_t        fn;
1462        u64                     val;
1463        struct regex            regex;
1464        unsigned short          *ops;
1465        struct ftrace_event_field *field;
1466        int                     offset;
1467        int                     not;
1468        int                     op;
1469};
1470
1471static inline bool is_string_field(struct ftrace_event_field *field)
1472{
1473        return field->filter_type == FILTER_DYN_STRING ||
1474               field->filter_type == FILTER_STATIC_STRING ||
1475               field->filter_type == FILTER_PTR_STRING ||
1476               field->filter_type == FILTER_COMM;
1477}
1478
1479static inline bool is_function_field(struct ftrace_event_field *field)
1480{
1481        return field->filter_type == FILTER_TRACE_FN;
1482}
1483
1484extern enum regex_type
1485filter_parse_regex(char *buff, int len, char **search, int *not);
1486extern void print_event_filter(struct trace_event_file *file,
1487                               struct trace_seq *s);
1488extern int apply_event_filter(struct trace_event_file *file,
1489                              char *filter_string);
1490extern int apply_subsystem_event_filter(struct trace_subsystem_dir *dir,
1491                                        char *filter_string);
1492extern void print_subsystem_event_filter(struct event_subsystem *system,
1493                                         struct trace_seq *s);
1494extern int filter_assign_type(const char *type);
1495extern int create_event_filter(struct trace_array *tr,
1496                               struct trace_event_call *call,
1497                               char *filter_str, bool set_str,
1498                               struct event_filter **filterp);
1499extern void free_event_filter(struct event_filter *filter);
1500
1501struct ftrace_event_field *
1502trace_find_event_field(struct trace_event_call *call, char *name);
1503
1504extern void trace_event_enable_cmd_record(bool enable);
1505extern void trace_event_enable_tgid_record(bool enable);
1506
1507extern int event_trace_init(void);
1508extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr);
1509extern int event_trace_del_tracer(struct trace_array *tr);
1510extern void __trace_early_add_events(struct trace_array *tr);
1511
1512extern struct trace_event_file *__find_event_file(struct trace_array *tr,
1513                                                  const char *system,
1514                                                  const char *event);
1515extern struct trace_event_file *find_event_file(struct trace_array *tr,
1516                                                const char *system,
1517                                                const char *event);
1518
1519static inline void *event_file_data(struct file *filp)
1520{
1521        return READ_ONCE(file_inode(filp)->i_private);
1522}
1523
1524extern struct mutex event_mutex;
1525extern struct list_head ftrace_events;
1526
1527extern const struct file_operations event_trigger_fops;
1528extern const struct file_operations event_hist_fops;
1529extern const struct file_operations event_hist_debug_fops;
1530extern const struct file_operations event_inject_fops;
1531
1532#ifdef CONFIG_HIST_TRIGGERS
1533extern int register_trigger_hist_cmd(void);
1534extern int register_trigger_hist_enable_disable_cmds(void);
1535#else
1536static inline int register_trigger_hist_cmd(void) { return 0; }
1537static inline int register_trigger_hist_enable_disable_cmds(void) { return 0; }
1538#endif
1539
1540extern int register_trigger_cmds(void);
1541extern void clear_event_triggers(struct trace_array *tr);
1542
1543struct event_trigger_data {
1544        unsigned long                   count;
1545        int                             ref;
1546        struct event_trigger_ops        *ops;
1547        struct event_command            *cmd_ops;
1548        struct event_filter __rcu       *filter;
1549        char                            *filter_str;
1550        void                            *private_data;
1551        bool                            paused;
1552        bool                            paused_tmp;
1553        struct list_head                list;
1554        char                            *name;
1555        struct list_head                named_list;
1556        struct event_trigger_data       *named_data;
1557};
1558
1559/* Avoid typos */
1560#define ENABLE_EVENT_STR        "enable_event"
1561#define DISABLE_EVENT_STR       "disable_event"
1562#define ENABLE_HIST_STR         "enable_hist"
1563#define DISABLE_HIST_STR        "disable_hist"
1564
1565struct enable_trigger_data {
1566        struct trace_event_file         *file;
1567        bool                            enable;
1568        bool                            hist;
1569};
1570
1571extern int event_enable_trigger_print(struct seq_file *m,
1572                                      struct event_trigger_ops *ops,
1573                                      struct event_trigger_data *data);
1574extern void event_enable_trigger_free(struct event_trigger_ops *ops,
1575                                      struct event_trigger_data *data);
1576extern int event_enable_trigger_func(struct event_command *cmd_ops,
1577                                     struct trace_event_file *file,
1578                                     char *glob, char *cmd, char *param);
1579extern int event_enable_register_trigger(char *glob,
1580                                         struct event_trigger_ops *ops,
1581                                         struct event_trigger_data *data,
1582                                         struct trace_event_file *file);
1583extern void event_enable_unregister_trigger(char *glob,
1584                                            struct event_trigger_ops *ops,
1585                                            struct event_trigger_data *test,
1586                                            struct trace_event_file *file);
1587extern void trigger_data_free(struct event_trigger_data *data);
1588extern int event_trigger_init(struct event_trigger_ops *ops,
1589                              struct event_trigger_data *data);
1590extern int trace_event_trigger_enable_disable(struct trace_event_file *file,
1591                                              int trigger_enable);
1592extern void update_cond_flag(struct trace_event_file *file);
1593extern int set_trigger_filter(char *filter_str,
1594                              struct event_trigger_data *trigger_data,
1595                              struct trace_event_file *file);
1596extern struct event_trigger_data *find_named_trigger(const char *name);
1597extern bool is_named_trigger(struct event_trigger_data *test);
1598extern int save_named_trigger(const char *name,
1599                              struct event_trigger_data *data);
1600extern void del_named_trigger(struct event_trigger_data *data);
1601extern void pause_named_trigger(struct event_trigger_data *data);
1602extern void unpause_named_trigger(struct event_trigger_data *data);
1603extern void set_named_trigger_data(struct event_trigger_data *data,
1604                                   struct event_trigger_data *named_data);
1605extern struct event_trigger_data *
1606get_named_trigger_data(struct event_trigger_data *data);
1607extern int register_event_command(struct event_command *cmd);
1608extern int unregister_event_command(struct event_command *cmd);
1609extern int register_trigger_hist_enable_disable_cmds(void);
1610
1611/**
1612 * struct event_trigger_ops - callbacks for trace event triggers
1613 *
1614 * The methods in this structure provide per-event trigger hooks for
1615 * various trigger operations.
1616 *
1617 * All the methods below, except for @init() and @free(), must be
1618 * implemented.
1619 *
1620 * @func: The trigger 'probe' function called when the triggering
1621 *      event occurs.  The data passed into this callback is the data
1622 *      that was supplied to the event_command @reg() function that
1623 *      registered the trigger (see struct event_command) along with
1624 *      the trace record, rec.
1625 *
1626 * @init: An optional initialization function called for the trigger
1627 *      when the trigger is registered (via the event_command reg()
1628 *      function).  This can be used to perform per-trigger
1629 *      initialization such as incrementing a per-trigger reference
1630 *      count, for instance.  This is usually implemented by the
1631 *      generic utility function @event_trigger_init() (see
1632 *      trace_event_triggers.c).
1633 *
1634 * @free: An optional de-initialization function called for the
1635 *      trigger when the trigger is unregistered (via the
1636 *      event_command @reg() function).  This can be used to perform
1637 *      per-trigger de-initialization such as decrementing a
1638 *      per-trigger reference count and freeing corresponding trigger
1639 *      data, for instance.  This is usually implemented by the
1640 *      generic utility function @event_trigger_free() (see
1641 *      trace_event_triggers.c).
1642 *
1643 * @print: The callback function invoked to have the trigger print
1644 *      itself.  This is usually implemented by a wrapper function
1645 *      that calls the generic utility function @event_trigger_print()
1646 *      (see trace_event_triggers.c).
1647 */
1648struct event_trigger_ops {
1649        void                    (*func)(struct event_trigger_data *data,
1650                                        void *rec,
1651                                        struct ring_buffer_event *rbe);
1652        int                     (*init)(struct event_trigger_ops *ops,
1653                                        struct event_trigger_data *data);
1654        void                    (*free)(struct event_trigger_ops *ops,
1655                                        struct event_trigger_data *data);
1656        int                     (*print)(struct seq_file *m,
1657                                         struct event_trigger_ops *ops,
1658                                         struct event_trigger_data *data);
1659};
1660
1661/**
1662 * struct event_command - callbacks and data members for event commands
1663 *
1664 * Event commands are invoked by users by writing the command name
1665 * into the 'trigger' file associated with a trace event.  The
1666 * parameters associated with a specific invocation of an event
1667 * command are used to create an event trigger instance, which is
1668 * added to the list of trigger instances associated with that trace
1669 * event.  When the event is hit, the set of triggers associated with
1670 * that event is invoked.
1671 *
1672 * The data members in this structure provide per-event command data
1673 * for various event commands.
1674 *
1675 * All the data members below, except for @post_trigger, must be set
1676 * for each event command.
1677 *
1678 * @name: The unique name that identifies the event command.  This is
1679 *      the name used when setting triggers via trigger files.
1680 *
1681 * @trigger_type: A unique id that identifies the event command
1682 *      'type'.  This value has two purposes, the first to ensure that
1683 *      only one trigger of the same type can be set at a given time
1684 *      for a particular event e.g. it doesn't make sense to have both
1685 *      a traceon and traceoff trigger attached to a single event at
1686 *      the same time, so traceon and traceoff have the same type
1687 *      though they have different names.  The @trigger_type value is
1688 *      also used as a bit value for deferring the actual trigger
1689 *      action until after the current event is finished.  Some
1690 *      commands need to do this if they themselves log to the trace
1691 *      buffer (see the @post_trigger() member below).  @trigger_type
1692 *      values are defined by adding new values to the trigger_type
1693 *      enum in include/linux/trace_events.h.
1694 *
1695 * @flags: See the enum event_command_flags below.
1696 *
1697 * All the methods below, except for @set_filter() and @unreg_all(),
1698 * must be implemented.
1699 *
1700 * @func: The callback function responsible for parsing and
1701 *      registering the trigger written to the 'trigger' file by the
1702 *      user.  It allocates the trigger instance and registers it with
1703 *      the appropriate trace event.  It makes use of the other
1704 *      event_command callback functions to orchestrate this, and is
1705 *      usually implemented by the generic utility function
1706 *      @event_trigger_callback() (see trace_event_triggers.c).
1707 *
1708 * @reg: Adds the trigger to the list of triggers associated with the
1709 *      event, and enables the event trigger itself, after
1710 *      initializing it (via the event_trigger_ops @init() function).
1711 *      This is also where commands can use the @trigger_type value to
1712 *      make the decision as to whether or not multiple instances of
1713 *      the trigger should be allowed.  This is usually implemented by
1714 *      the generic utility function @register_trigger() (see
1715 *      trace_event_triggers.c).
1716 *
1717 * @unreg: Removes the trigger from the list of triggers associated
1718 *      with the event, and disables the event trigger itself, after
1719 *      initializing it (via the event_trigger_ops @free() function).
1720 *      This is usually implemented by the generic utility function
1721 *      @unregister_trigger() (see trace_event_triggers.c).
1722 *
1723 * @unreg_all: An optional function called to remove all the triggers
1724 *      from the list of triggers associated with the event.  Called
1725 *      when a trigger file is opened in truncate mode.
1726 *
1727 * @set_filter: An optional function called to parse and set a filter
1728 *      for the trigger.  If no @set_filter() method is set for the
1729 *      event command, filters set by the user for the command will be
1730 *      ignored.  This is usually implemented by the generic utility
1731 *      function @set_trigger_filter() (see trace_event_triggers.c).
1732 *
1733 * @get_trigger_ops: The callback function invoked to retrieve the
1734 *      event_trigger_ops implementation associated with the command.
1735 */
1736struct event_command {
1737        struct list_head        list;
1738        char                    *name;
1739        enum event_trigger_type trigger_type;
1740        int                     flags;
1741        int                     (*func)(struct event_command *cmd_ops,
1742                                        struct trace_event_file *file,
1743                                        char *glob, char *cmd, char *params);
1744        int                     (*reg)(char *glob,
1745                                       struct event_trigger_ops *ops,
1746                                       struct event_trigger_data *data,
1747                                       struct trace_event_file *file);
1748        void                    (*unreg)(char *glob,
1749                                         struct event_trigger_ops *ops,
1750                                         struct event_trigger_data *data,
1751                                         struct trace_event_file *file);
1752        void                    (*unreg_all)(struct trace_event_file *file);
1753        int                     (*set_filter)(char *filter_str,
1754                                              struct event_trigger_data *data,
1755                                              struct trace_event_file *file);
1756        struct event_trigger_ops *(*get_trigger_ops)(char *cmd, char *param);
1757};
1758
1759/**
1760 * enum event_command_flags - flags for struct event_command
1761 *
1762 * @POST_TRIGGER: A flag that says whether or not this command needs
1763 *      to have its action delayed until after the current event has
1764 *      been closed.  Some triggers need to avoid being invoked while
1765 *      an event is currently in the process of being logged, since
1766 *      the trigger may itself log data into the trace buffer.  Thus
1767 *      we make sure the current event is committed before invoking
1768 *      those triggers.  To do that, the trigger invocation is split
1769 *      in two - the first part checks the filter using the current
1770 *      trace record; if a command has the @post_trigger flag set, it
1771 *      sets a bit for itself in the return value, otherwise it
1772 *      directly invokes the trigger.  Once all commands have been
1773 *      either invoked or set their return flag, the current record is
1774 *      either committed or discarded.  At that point, if any commands
1775 *      have deferred their triggers, those commands are finally
1776 *      invoked following the close of the current event.  In other
1777 *      words, if the event_trigger_ops @func() probe implementation
1778 *      itself logs to the trace buffer, this flag should be set,
1779 *      otherwise it can be left unspecified.
1780 *
1781 * @NEEDS_REC: A flag that says whether or not this command needs
1782 *      access to the trace record in order to perform its function,
1783 *      regardless of whether or not it has a filter associated with
1784 *      it (filters make a trigger require access to the trace record
1785 *      but are not always present).
1786 */
1787enum event_command_flags {
1788        EVENT_CMD_FL_POST_TRIGGER       = 1,
1789        EVENT_CMD_FL_NEEDS_REC          = 2,
1790};
1791
1792static inline bool event_command_post_trigger(struct event_command *cmd_ops)
1793{
1794        return cmd_ops->flags & EVENT_CMD_FL_POST_TRIGGER;
1795}
1796
1797static inline bool event_command_needs_rec(struct event_command *cmd_ops)
1798{
1799        return cmd_ops->flags & EVENT_CMD_FL_NEEDS_REC;
1800}
1801
1802extern int trace_event_enable_disable(struct trace_event_file *file,
1803                                      int enable, int soft_disable);
1804extern int tracing_alloc_snapshot(void);
1805extern void tracing_snapshot_cond(struct trace_array *tr, void *cond_data);
1806extern int tracing_snapshot_cond_enable(struct trace_array *tr, void *cond_data, cond_update_fn_t update);
1807
1808extern int tracing_snapshot_cond_disable(struct trace_array *tr);
1809extern void *tracing_cond_snapshot_data(struct trace_array *tr);
1810
1811extern const char *__start___trace_bprintk_fmt[];
1812extern const char *__stop___trace_bprintk_fmt[];
1813
1814extern const char *__start___tracepoint_str[];
1815extern const char *__stop___tracepoint_str[];
1816
1817void trace_printk_control(bool enabled);
1818void trace_printk_start_comm(void);
1819int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set);
1820int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled);
1821
1822/* Used from boot time tracer */
1823extern int trace_set_options(struct trace_array *tr, char *option);
1824extern int tracing_set_tracer(struct trace_array *tr, const char *buf);
1825extern ssize_t tracing_resize_ring_buffer(struct trace_array *tr,
1826                                          unsigned long size, int cpu_id);
1827extern int tracing_set_cpumask(struct trace_array *tr,
1828                                cpumask_var_t tracing_cpumask_new);
1829
1830
1831#define MAX_EVENT_NAME_LEN      64
1832
1833extern int trace_run_command(const char *buf, int (*createfn)(int, char**));
1834extern ssize_t trace_parse_run_command(struct file *file,
1835                const char __user *buffer, size_t count, loff_t *ppos,
1836                int (*createfn)(int, char**));
1837
1838extern unsigned int err_pos(char *cmd, const char *str);
1839extern void tracing_log_err(struct trace_array *tr,
1840                            const char *loc, const char *cmd,
1841                            const char **errs, u8 type, u8 pos);
1842
1843/*
1844 * Normal trace_printk() and friends allocates special buffers
1845 * to do the manipulation, as well as saves the print formats
1846 * into sections to display. But the trace infrastructure wants
1847 * to use these without the added overhead at the price of being
1848 * a bit slower (used mainly for warnings, where we don't care
1849 * about performance). The internal_trace_puts() is for such
1850 * a purpose.
1851 */
1852#define internal_trace_puts(str) __trace_puts(_THIS_IP_, str, strlen(str))
1853
1854#undef FTRACE_ENTRY
1855#define FTRACE_ENTRY(call, struct_name, id, tstruct, print)     \
1856        extern struct trace_event_call                                  \
1857        __aligned(4) event_##call;
1858#undef FTRACE_ENTRY_DUP
1859#define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print) \
1860        FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
1861#undef FTRACE_ENTRY_PACKED
1862#define FTRACE_ENTRY_PACKED(call, struct_name, id, tstruct, print) \
1863        FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
1864
1865#include "trace_entries.h"
1866
1867#if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER)
1868int perf_ftrace_event_register(struct trace_event_call *call,
1869                               enum trace_reg type, void *data);
1870#else
1871#define perf_ftrace_event_register NULL
1872#endif
1873
1874#ifdef CONFIG_FTRACE_SYSCALLS
1875void init_ftrace_syscalls(void);
1876const char *get_syscall_name(int syscall);
1877#else
1878static inline void init_ftrace_syscalls(void) { }
1879static inline const char *get_syscall_name(int syscall)
1880{
1881        return NULL;
1882}
1883#endif
1884
1885#ifdef CONFIG_EVENT_TRACING
1886void trace_event_init(void);
1887void trace_event_eval_update(struct trace_eval_map **map, int len);
1888/* Used from boot time tracer */
1889extern int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set);
1890extern int trigger_process_regex(struct trace_event_file *file, char *buff);
1891#else
1892static inline void __init trace_event_init(void) { }
1893static inline void trace_event_eval_update(struct trace_eval_map **map, int len) { }
1894#endif
1895
1896#ifdef CONFIG_TRACER_SNAPSHOT
1897void tracing_snapshot_instance(struct trace_array *tr);
1898int tracing_alloc_snapshot_instance(struct trace_array *tr);
1899#else
1900static inline void tracing_snapshot_instance(struct trace_array *tr) { }
1901static inline int tracing_alloc_snapshot_instance(struct trace_array *tr)
1902{
1903        return 0;
1904}
1905#endif
1906
1907#ifdef CONFIG_PREEMPT_TRACER
1908void tracer_preempt_on(unsigned long a0, unsigned long a1);
1909void tracer_preempt_off(unsigned long a0, unsigned long a1);
1910#else
1911static inline void tracer_preempt_on(unsigned long a0, unsigned long a1) { }
1912static inline void tracer_preempt_off(unsigned long a0, unsigned long a1) { }
1913#endif
1914#ifdef CONFIG_IRQSOFF_TRACER
1915void tracer_hardirqs_on(unsigned long a0, unsigned long a1);
1916void tracer_hardirqs_off(unsigned long a0, unsigned long a1);
1917#else
1918static inline void tracer_hardirqs_on(unsigned long a0, unsigned long a1) { }
1919static inline void tracer_hardirqs_off(unsigned long a0, unsigned long a1) { }
1920#endif
1921
1922extern struct trace_iterator *tracepoint_print_iter;
1923
1924/*
1925 * Reset the state of the trace_iterator so that it can read consumed data.
1926 * Normally, the trace_iterator is used for reading the data when it is not
1927 * consumed, and must retain state.
1928 */
1929static __always_inline void trace_iterator_reset(struct trace_iterator *iter)
1930{
1931        const size_t offset = offsetof(struct trace_iterator, seq);
1932
1933        /*
1934         * Keep gcc from complaining about overwriting more than just one
1935         * member in the structure.
1936         */
1937        memset((char *)iter + offset, 0, sizeof(struct trace_iterator) - offset);
1938
1939        iter->pos = -1;
1940}
1941
1942/* Check the name is good for event/group/fields */
1943static inline bool is_good_name(const char *name)
1944{
1945        if (!isalpha(*name) && *name != '_')
1946                return false;
1947        while (*++name != '\0') {
1948                if (!isalpha(*name) && !isdigit(*name) && *name != '_')
1949                        return false;
1950        }
1951        return true;
1952}
1953
1954#endif /* _LINUX_KERNEL_TRACE_H */
1955