trace.h

   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#include <linux/once_lite.h>
  24#include <linux/ftrace_regs.h>
  25#include <linux/llist.h>
  26
  27#include "pid_list.h"
  28
  29#ifdef CONFIG_FTRACE_SYSCALLS
  30#include <asm/unistd.h>		/* For NR_syscalls	     */
  31#include <asm/syscall.h>	/* some archs define it here */
  32#endif
  33
  34#define TRACE_MODE_WRITE	0640
  35#define TRACE_MODE_READ		0440
  36
  37enum trace_type {
  38	__TRACE_FIRST_TYPE = 0,
  39
  40	TRACE_FN,
  41	TRACE_CTX,
  42	TRACE_WAKE,
  43	TRACE_STACK,
  44	TRACE_PRINT,
  45	TRACE_BPRINT,
  46	TRACE_MMIO_RW,
  47	TRACE_MMIO_MAP,
  48	TRACE_BRANCH,
  49	TRACE_GRAPH_RET,
  50	TRACE_GRAPH_ENT,
  51	TRACE_GRAPH_RETADDR_ENT,
  52	TRACE_USER_STACK,
  53	TRACE_BLK,
  54	TRACE_BPUTS,
  55	TRACE_HWLAT,
  56	TRACE_OSNOISE,
  57	TRACE_TIMERLAT,
  58	TRACE_RAW_DATA,
  59	TRACE_FUNC_REPEATS,
  60
  61	__TRACE_LAST_TYPE,
  62};
  63
  64
  65#undef __field
  66#define __field(type, item)		type	item;
  67
  68#undef __field_fn
  69#define __field_fn(type, item)		type	item;
  70
  71#undef __field_packed
  72#define __field_packed(type, item)	type	item;
  73
  74#undef __field_struct
  75#define __field_struct(type, item)	__field(type, item)
  76
  77#undef __field_desc
  78#define __field_desc(type, container, item)
  79
  80#undef __field_desc_packed
  81#define __field_desc_packed(type, container, item)
  82
  83#undef __array
  84#define __array(type, item, size)	type	item[size];
  85
  86/*
  87 * For backward compatibility, older user space expects to see the
  88 * kernel_stack event with a fixed size caller field. But today the fix
  89 * size is ignored by the kernel, and the real structure is dynamic.
  90 * Expose to user space: "unsigned long caller[8];" but the real structure
  91 * will be "unsigned long caller[] __counted_by(size)"
  92 */
  93#undef __stack_array
  94#define __stack_array(type, item, size, field)		type item[] __counted_by(field);
  95
  96#undef __array_desc
  97#define __array_desc(type, container, item, size)
  98
  99#undef __dynamic_array
 100#define __dynamic_array(type, item)	type	item[];
 101
 102#undef __rel_dynamic_array
 103#define __rel_dynamic_array(type, item)	type	item[];
 104
 105#undef F_STRUCT
 106#define F_STRUCT(args...)		args
 107
 108#undef FTRACE_ENTRY
 109#define FTRACE_ENTRY(name, struct_name, id, tstruct, print)		\
 110	struct struct_name {						\
 111		struct trace_entry	ent;				\
 112		tstruct							\
 113	}
 114
 115#undef FTRACE_ENTRY_DUP
 116#define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk)
 117
 118#undef FTRACE_ENTRY_REG
 119#define FTRACE_ENTRY_REG(name, struct_name, id, tstruct, print,	regfn)	\
 120	FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print))
 121
 122#undef FTRACE_ENTRY_PACKED
 123#define FTRACE_ENTRY_PACKED(name, struct_name, id, tstruct, print)	\
 124	FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print)) __packed
 125
 126#include "trace_entries.h"
 127
 128/* Use this for memory failure errors */
 129#define MEM_FAIL(condition, fmt, ...)					\
 130	DO_ONCE_LITE_IF(condition, pr_err, "ERROR: " fmt, ##__VA_ARGS__)
 131
 132#define FAULT_STRING "(fault)"
 133
 134#define HIST_STACKTRACE_DEPTH	16
 135#define HIST_STACKTRACE_SIZE	(HIST_STACKTRACE_DEPTH * sizeof(unsigned long))
 136#define HIST_STACKTRACE_SKIP	5
 137
 138#define SYSCALL_FAULT_USER_MAX 165
 139
 140/*
 141 * syscalls are special, and need special handling, this is why
 142 * they are not included in trace_entries.h
 143 */
 144struct syscall_trace_enter {
 145	struct trace_entry	ent;
 146	int			nr;
 147	unsigned long		args[];
 148};
 149
 150struct syscall_trace_exit {
 151	struct trace_entry	ent;
 152	int			nr;
 153	long			ret;
 154};
 155
 156struct kprobe_trace_entry_head {
 157	struct trace_entry	ent;
 158	unsigned long		ip;
 159};
 160
 161struct eprobe_trace_entry_head {
 162	struct trace_entry	ent;
 163};
 164
 165struct kretprobe_trace_entry_head {
 166	struct trace_entry	ent;
 167	unsigned long		func;
 168	unsigned long		ret_ip;
 169};
 170
 171struct fentry_trace_entry_head {
 172	struct trace_entry	ent;
 173	unsigned long		ip;
 174};
 175
 176struct fexit_trace_entry_head {
 177	struct trace_entry	ent;
 178	unsigned long		func;
 179	unsigned long		ret_ip;
 180};
 181
 182#define TRACE_BUF_SIZE		1024
 183
 184struct trace_array;
 185
 186/*
 187 * The CPU trace array - it consists of thousands of trace entries
 188 * plus some other descriptor data: (for example which task started
 189 * the trace, etc.)
 190 */
 191struct trace_array_cpu {
 192	local_t			disabled;
 193
 194	unsigned long		entries;
 195	unsigned long		saved_latency;
 196	unsigned long		critical_start;
 197	unsigned long		critical_end;
 198	unsigned long		critical_sequence;
 199	unsigned long		nice;
 200	unsigned long		policy;
 201	unsigned long		rt_priority;
 202	unsigned long		skipped_entries;
 203	u64			preempt_timestamp;
 204	pid_t			pid;
 205	kuid_t			uid;
 206	char			comm[TASK_COMM_LEN];
 207
 208#ifdef CONFIG_FUNCTION_TRACER
 209	int			ftrace_ignore_pid;
 210#endif
 211	bool			ignore_pid;
 212};
 213
 214struct tracer;
 215struct trace_option_dentry;
 216
 217struct array_buffer {
 218	struct trace_array		*tr;
 219	struct trace_buffer		*buffer;
 220	struct trace_array_cpu __percpu	*data;
 221	u64				time_start;
 222	int				cpu;
 223};
 224
 225#define TRACE_FLAGS_MAX_SIZE		64
 226
 227struct trace_options {
 228	struct tracer			*tracer;
 229	struct trace_option_dentry	*topts;
 230};
 231
 232struct trace_pid_list *trace_pid_list_alloc(void);
 233void trace_pid_list_free(struct trace_pid_list *pid_list);
 234bool trace_pid_list_is_set(struct trace_pid_list *pid_list, unsigned int pid);
 235int trace_pid_list_set(struct trace_pid_list *pid_list, unsigned int pid);
 236int trace_pid_list_clear(struct trace_pid_list *pid_list, unsigned int pid);
 237int trace_pid_list_first(struct trace_pid_list *pid_list, unsigned int *pid);
 238int trace_pid_list_next(struct trace_pid_list *pid_list, unsigned int pid,
 239			unsigned int *next);
 240
 241enum {
 242	TRACE_PIDS		= BIT(0),
 243	TRACE_NO_PIDS		= BIT(1),
 244};
 245
 246static inline bool pid_type_enabled(int type, struct trace_pid_list *pid_list,
 247				    struct trace_pid_list *no_pid_list)
 248{
 249	/* Return true if the pid list in type has pids */
 250	return ((type & TRACE_PIDS) && pid_list) ||
 251		((type & TRACE_NO_PIDS) && no_pid_list);
 252}
 253
 254static inline bool still_need_pid_events(int type, struct trace_pid_list *pid_list,
 255					 struct trace_pid_list *no_pid_list)
 256{
 257	/*
 258	 * Turning off what is in @type, return true if the "other"
 259	 * pid list, still has pids in it.
 260	 */
 261	return (!(type & TRACE_PIDS) && pid_list) ||
 262		(!(type & TRACE_NO_PIDS) && no_pid_list);
 263}
 264
 265typedef bool (*cond_update_fn_t)(struct trace_array *tr, void *cond_data);
 266
 267/**
 268 * struct cond_snapshot - conditional snapshot data and callback
 269 *
 270 * The cond_snapshot structure encapsulates a callback function and
 271 * data associated with the snapshot for a given tracing instance.
 272 *
 273 * When a snapshot is taken conditionally, by invoking
 274 * tracing_snapshot_cond(tr, cond_data), the cond_data passed in is
 275 * passed in turn to the cond_snapshot.update() function.  That data
 276 * can be compared by the update() implementation with the cond_data
 277 * contained within the struct cond_snapshot instance associated with
 278 * the trace_array.  Because the tr->max_lock is held throughout the
 279 * update() call, the update() function can directly retrieve the
 280 * cond_snapshot and cond_data associated with the per-instance
 281 * snapshot associated with the trace_array.
 282 *
 283 * The cond_snapshot.update() implementation can save data to be
 284 * associated with the snapshot if it decides to, and returns 'true'
 285 * in that case, or it returns 'false' if the conditional snapshot
 286 * shouldn't be taken.
 287 *
 288 * The cond_snapshot instance is created and associated with the
 289 * user-defined cond_data by tracing_cond_snapshot_enable().
 290 * Likewise, the cond_snapshot instance is destroyed and is no longer
 291 * associated with the trace instance by
 292 * tracing_cond_snapshot_disable().
 293 *
 294 * The method below is required.
 295 *
 296 * @update: When a conditional snapshot is invoked, the update()
 297 *	callback function is invoked with the tr->max_lock held.  The
 298 *	update() implementation signals whether or not to actually
 299 *	take the snapshot, by returning 'true' if so, 'false' if no
 300 *	snapshot should be taken.  Because the max_lock is held for
 301 *	the duration of update(), the implementation is safe to
 302 *	directly retrieved and save any implementation data it needs
 303 *	to in association with the snapshot.
 304 */
 305struct cond_snapshot {
 306	void				*cond_data;
 307	cond_update_fn_t		update;
 308};
 309
 310/*
 311 * struct trace_func_repeats - used to keep track of the consecutive
 312 * (on the same CPU) calls of a single function.
 313 */
 314struct trace_func_repeats {
 315	unsigned long	ip;
 316	unsigned long	parent_ip;
 317	unsigned long	count;
 318	u64		ts_last_call;
 319};
 320
 321struct trace_module_delta {
 322	struct rcu_head	rcu;
 323	long		delta[];
 324};
 325
 326/*
 327 * The trace array - an array of per-CPU trace arrays. This is the
 328 * highest level data structure that individual tracers deal with.
 329 * They have on/off state as well:
 330 */
 331struct trace_array {
 332	struct list_head	list;
 333	char			*name;
 334	struct array_buffer	array_buffer;
 335#ifdef CONFIG_TRACER_MAX_TRACE
 336	/*
 337	 * The max_buffer is used to snapshot the trace when a maximum
 338	 * latency is reached, or when the user initiates a snapshot.
 339	 * Some tracers will use this to store a maximum trace while
 340	 * it continues examining live traces.
 341	 *
 342	 * The buffers for the max_buffer are set up the same as the array_buffer
 343	 * When a snapshot is taken, the buffer of the max_buffer is swapped
 344	 * with the buffer of the array_buffer and the buffers are reset for
 345	 * the array_buffer so the tracing can continue.
 346	 */
 347	struct array_buffer	max_buffer;
 348	bool			allocated_snapshot;
 349	spinlock_t		snapshot_trigger_lock;
 350	unsigned int		snapshot;
 351	unsigned long		max_latency;
 352#ifdef CONFIG_FSNOTIFY
 353	struct dentry		*d_max_latency;
 354	struct work_struct	fsnotify_work;
 355	struct irq_work		fsnotify_irqwork;
 356#endif
 357#endif
 358	/* The below is for memory mapped ring buffer */
 359	unsigned int		mapped;
 360	unsigned long		range_addr_start;
 361	unsigned long		range_addr_size;
 362	char			*range_name;
 363	long			text_delta;
 364	struct trace_module_delta *module_delta;
 365	void			*scratch; /* pointer in persistent memory */
 366	int			scratch_size;
 367
 368	int			buffer_disabled;
 369
 370	struct trace_pid_list	__rcu *filtered_pids;
 371	struct trace_pid_list	__rcu *filtered_no_pids;
 372	/*
 373	 * max_lock is used to protect the swapping of buffers
 374	 * when taking a max snapshot. The buffers themselves are
 375	 * protected by per_cpu spinlocks. But the action of the swap
 376	 * needs its own lock.
 377	 *
 378	 * This is defined as a arch_spinlock_t in order to help
 379	 * with performance when lockdep debugging is enabled.
 380	 *
 381	 * It is also used in other places outside the update_max_tr
 382	 * so it needs to be defined outside of the
 383	 * CONFIG_TRACER_MAX_TRACE.
 384	 */
 385	arch_spinlock_t		max_lock;
 386#ifdef CONFIG_FTRACE_SYSCALLS
 387	int			sys_refcount_enter;
 388	int			sys_refcount_exit;
 389	struct trace_event_file	*enter_syscall_files[NR_syscalls];
 390	struct trace_event_file	*exit_syscall_files[NR_syscalls];
 391#endif
 392	int			stop_count;
 393	int			clock_id;
 394	int			nr_topts;
 395	bool			clear_trace;
 396	int			buffer_percent;
 397	unsigned int		n_err_log_entries;
 398	struct tracer		*current_trace;
 399	struct tracer_flags	*current_trace_flags;
 400	u64			trace_flags;
 401	unsigned char		trace_flags_index[TRACE_FLAGS_MAX_SIZE];
 402	unsigned int		flags;
 403	raw_spinlock_t		start_lock;
 404	const char		*system_names;
 405	struct list_head	err_log;
 406	struct dentry		*dir;
 407	struct dentry		*options;
 408	struct dentry		*percpu_dir;
 409	struct eventfs_inode	*event_dir;
 410	struct trace_options	*topts;
 411	struct list_head	systems;
 412	struct list_head	events;
 413	struct list_head	marker_list;
 414	struct list_head	tracers;
 415	struct trace_event_file *trace_marker_file;
 416	cpumask_var_t		tracing_cpumask; /* only trace on set CPUs */
 417	/* one per_cpu trace_pipe can be opened by only one user */
 418	cpumask_var_t		pipe_cpumask;
 419	int			ref;
 420	int			trace_ref;
 421#ifdef CONFIG_MODULES
 422	struct list_head	mod_events;
 423#endif
 424#ifdef CONFIG_FUNCTION_TRACER
 425	struct ftrace_ops	*ops;
 426	struct trace_pid_list	__rcu *function_pids;
 427	struct trace_pid_list	__rcu *function_no_pids;
 428#ifdef CONFIG_FUNCTION_GRAPH_TRACER
 429	struct fgraph_ops	*gops;
 430#endif
 431#ifdef CONFIG_DYNAMIC_FTRACE
 432	/* All of these are protected by the ftrace_lock */
 433	struct list_head	func_probes;
 434	struct list_head	mod_trace;
 435	struct list_head	mod_notrace;
 436#endif
 437	/* function tracing enabled */
 438	int			function_enabled;
 439#endif
 440	int			no_filter_buffering_ref;
 441	unsigned int		syscall_buf_sz;
 442	struct list_head	hist_vars;
 443#ifdef CONFIG_TRACER_SNAPSHOT
 444	struct cond_snapshot	*cond_snapshot;
 445#endif
 446	struct trace_func_repeats	__percpu *last_func_repeats;
 447	/*
 448	 * On boot up, the ring buffer is set to the minimum size, so that
 449	 * we do not waste memory on systems that are not using tracing.
 450	 */
 451	bool ring_buffer_expanded;
 452};
 453
 454enum {
 455	TRACE_ARRAY_FL_GLOBAL		= BIT(0),
 456	TRACE_ARRAY_FL_BOOT		= BIT(1),
 457	TRACE_ARRAY_FL_LAST_BOOT	= BIT(2),
 458	TRACE_ARRAY_FL_MOD_INIT		= BIT(3),
 459	TRACE_ARRAY_FL_MEMMAP		= BIT(4),
 460	TRACE_ARRAY_FL_VMALLOC		= BIT(5),
 461};
 462
 463#ifdef CONFIG_MODULES
 464bool module_exists(const char *module);
 465#else
 466static inline bool module_exists(const char *module)
 467{
 468	return false;
 469}
 470#endif
 471
 472extern struct list_head ftrace_trace_arrays;
 473
 474extern struct mutex trace_types_lock;
 475
 476extern int trace_array_get(struct trace_array *tr);
 477extern int tracing_check_open_get_tr(struct trace_array *tr);
 478extern struct trace_array *trace_array_find(const char *instance);
 479extern struct trace_array *trace_array_find_get(const char *instance);
 480
 481extern u64 tracing_event_time_stamp(struct trace_buffer *buffer, struct ring_buffer_event *rbe);
 482extern int tracing_set_filter_buffering(struct trace_array *tr, bool set);
 483extern int tracing_set_clock(struct trace_array *tr, const char *clockstr);
 484
 485extern bool trace_clock_in_ns(struct trace_array *tr);
 486
 487extern unsigned long trace_adjust_address(struct trace_array *tr, unsigned long addr);
 488
 489/*
 490 * The global tracer (top) should be the first trace array added,
 491 * but we check the flag anyway.
 492 */
 493static inline struct trace_array *top_trace_array(void)
 494{
 495	struct trace_array *tr;
 496
 497	if (list_empty(&ftrace_trace_arrays))
 498		return NULL;
 499
 500	tr = list_entry(ftrace_trace_arrays.prev,
 501			typeof(*tr), list);
 502	WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL));
 503	return tr;
 504}
 505
 506#define FTRACE_CMP_TYPE(var, type) \
 507	__builtin_types_compatible_p(typeof(var), type *)
 508
 509#undef IF_ASSIGN
 510#define IF_ASSIGN(var, entry, etype, id)			\
 511	if (FTRACE_CMP_TYPE(var, etype)) {			\
 512		var = (typeof(var))(entry);			\
 513		WARN_ON(id != 0 && (entry)->type != id);	\
 514		break;						\
 515	}
 516
 517/* Will cause compile errors if type is not found. */
 518extern void __ftrace_bad_type(void);
 519
 520/*
 521 * The trace_assign_type is a verifier that the entry type is
 522 * the same as the type being assigned. To add new types simply
 523 * add a line with the following format:
 524 *
 525 * IF_ASSIGN(var, ent, type, id);
 526 *
 527 *  Where "type" is the trace type that includes the trace_entry
 528 *  as the "ent" item. And "id" is the trace identifier that is
 529 *  used in the trace_type enum.
 530 *
 531 *  If the type can have more than one id, then use zero.
 532 */
 533#define trace_assign_type(var, ent)					\
 534	do {								\
 535		IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN);	\
 536		IF_ASSIGN(var, ent, struct ctx_switch_entry, 0);	\
 537		IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK);	\
 538		IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
 539		IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT);	\
 540		IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT);	\
 541		IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS);	\
 542		IF_ASSIGN(var, ent, struct hwlat_entry, TRACE_HWLAT);	\
 543		IF_ASSIGN(var, ent, struct osnoise_entry, TRACE_OSNOISE);\
 544		IF_ASSIGN(var, ent, struct timerlat_entry, TRACE_TIMERLAT);\
 545		IF_ASSIGN(var, ent, struct raw_data_entry, TRACE_RAW_DATA);\
 546		IF_ASSIGN(var, ent, struct trace_mmiotrace_rw,		\
 547			  TRACE_MMIO_RW);				\
 548		IF_ASSIGN(var, ent, struct trace_mmiotrace_map,		\
 549			  TRACE_MMIO_MAP);				\
 550		IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
 551		IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry,	\
 552			  TRACE_GRAPH_ENT);		\
 553		IF_ASSIGN(var, ent, struct fgraph_retaddr_ent_entry,\
 554			  TRACE_GRAPH_RETADDR_ENT);		\
 555		IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry,	\
 556			  TRACE_GRAPH_RET);		\
 557		IF_ASSIGN(var, ent, struct func_repeats_entry,		\
 558			  TRACE_FUNC_REPEATS);				\
 559		__ftrace_bad_type();					\
 560	} while (0)
 561
 562/*
 563 * An option specific to a tracer. This is a boolean value.
 564 * The bit is the bit index that sets its value on the
 565 * flags value in struct tracer_flags.
 566 */
 567struct tracer_opt {
 568	const char	*name; /* Will appear on the trace_options file */
 569	u32		bit; /* Mask assigned in val field in tracer_flags */
 570};
 571
 572/*
 573 * The set of specific options for a tracer. Your tracer
 574 * have to set the initial value of the flags val.
 575 */
 576struct tracer_flags {
 577	u32			val;
 578	struct tracer_opt	*opts;
 579	struct tracer		*trace;
 580};
 581
 582/* Makes more easy to define a tracer opt */
 583#define TRACER_OPT(s, b)	.name = #s, .bit = b
 584
 585
 586struct trace_option_dentry {
 587	struct tracer_opt		*opt;
 588	struct tracer_flags		*flags;
 589	struct trace_array		*tr;
 590	struct dentry			*entry;
 591};
 592
 593/**
 594 * struct tracer - a specific tracer and its callbacks to interact with tracefs
 595 * @name: the name chosen to select it on the available_tracers file
 596 * @init: called when one switches to this tracer (echo name > current_tracer)
 597 * @reset: called when one switches to another tracer
 598 * @start: called when tracing is unpaused (echo 1 > tracing_on)
 599 * @stop: called when tracing is paused (echo 0 > tracing_on)
 600 * @update_thresh: called when tracing_thresh is updated
 601 * @open: called when the trace file is opened
 602 * @pipe_open: called when the trace_pipe file is opened
 603 * @close: called when the trace file is released
 604 * @pipe_close: called when the trace_pipe file is released
 605 * @read: override the default read callback on trace_pipe
 606 * @splice_read: override the default splice_read callback on trace_pipe
 607 * @selftest: selftest to run on boot (see trace_selftest.c)
 608 * @print_headers: override the first lines that describe your columns
 609 * @print_line: callback that prints a trace
 610 * @set_flag: signals one of your private flags changed (trace_options file)
 611 * @flags: your private flags
 612 */
 613struct tracer {
 614	const char		*name;
 615	int			(*init)(struct trace_array *tr);
 616	void			(*reset)(struct trace_array *tr);
 617	void			(*start)(struct trace_array *tr);
 618	void			(*stop)(struct trace_array *tr);
 619	int			(*update_thresh)(struct trace_array *tr);
 620	void			(*open)(struct trace_iterator *iter);
 621	void			(*pipe_open)(struct trace_iterator *iter);
 622	void			(*close)(struct trace_iterator *iter);
 623	void			(*pipe_close)(struct trace_iterator *iter);
 624	ssize_t			(*read)(struct trace_iterator *iter,
 625					struct file *filp, char __user *ubuf,
 626					size_t cnt, loff_t *ppos);
 627	ssize_t			(*splice_read)(struct trace_iterator *iter,
 628					       struct file *filp,
 629					       loff_t *ppos,
 630					       struct pipe_inode_info *pipe,
 631					       size_t len,
 632					       unsigned int flags);
 633#ifdef CONFIG_FTRACE_STARTUP_TEST
 634	int			(*selftest)(struct tracer *trace,
 635					    struct trace_array *tr);
 636#endif
 637	void			(*print_header)(struct seq_file *m);
 638	enum print_line_t	(*print_line)(struct trace_iterator *iter);
 639	/* If you handled the flag setting, return 0 */
 640	int			(*set_flag)(struct trace_array *tr,
 641					    u32 old_flags, u32 bit, int set);
 642	/* Return 0 if OK with change, else return non-zero */
 643	int			(*flag_changed)(struct trace_array *tr,
 644						u64 mask, int set);
 645	struct tracer		*next;
 646	struct tracer_flags	*flags;
 647	struct tracer_flags	*default_flags;
 648	int			enabled;
 649	bool			print_max;
 650	bool			allow_instances;
 651#ifdef CONFIG_TRACER_MAX_TRACE
 652	bool			use_max_tr;
 653#endif
 654	/* True if tracer cannot be enabled in kernel param */
 655	bool			noboot;
 656};
 657
 658static inline struct ring_buffer_iter *
 659trace_buffer_iter(struct trace_iterator *iter, int cpu)
 660{
 661	return iter->buffer_iter ? iter->buffer_iter[cpu] : NULL;
 662}
 663
 664int tracer_init(struct tracer *t, struct trace_array *tr);
 665int tracing_is_enabled(void);
 666void tracing_reset_online_cpus(struct array_buffer *buf);
 667void tracing_reset_all_online_cpus(void);
 668void tracing_reset_all_online_cpus_unlocked(void);
 669int tracing_open_generic(struct inode *inode, struct file *filp);
 670int tracing_open_generic_tr(struct inode *inode, struct file *filp);
 671int tracing_release_generic_tr(struct inode *inode, struct file *file);
 672int tracing_open_file_tr(struct inode *inode, struct file *filp);
 673int tracing_release_file_tr(struct inode *inode, struct file *filp);
 674int tracing_single_release_file_tr(struct inode *inode, struct file *filp);
 675bool tracing_is_disabled(void);
 676bool tracer_tracing_is_on(struct trace_array *tr);
 677void tracer_tracing_on(struct trace_array *tr);
 678void tracer_tracing_off(struct trace_array *tr);
 679void tracer_tracing_disable(struct trace_array *tr);
 680void tracer_tracing_enable(struct trace_array *tr);
 681struct dentry *trace_create_file(const char *name,
 682				 umode_t mode,
 683				 struct dentry *parent,
 684				 void *data,
 685				 const struct file_operations *fops);
 686
 687
 688/**
 689 * tracer_tracing_is_on_cpu - show real state of ring buffer enabled on for a cpu
 690 * @tr : the trace array to know if ring buffer is enabled
 691 * @cpu: The cpu buffer to check if enabled
 692 *
 693 * Shows real state of the per CPU buffer if it is enabled or not.
 694 */
 695static inline bool tracer_tracing_is_on_cpu(struct trace_array *tr, int cpu)
 696{
 697	if (tr->array_buffer.buffer)
 698		return ring_buffer_record_is_on_cpu(tr->array_buffer.buffer, cpu);
 699	return false;
 700}
 701
 702int tracing_init_dentry(void);
 703
 704struct ring_buffer_event;
 705
 706struct ring_buffer_event *
 707trace_buffer_lock_reserve(struct trace_buffer *buffer,
 708			  int type,
 709			  unsigned long len,
 710			  unsigned int trace_ctx);
 711
 712int ring_buffer_meta_seq_init(struct file *file, struct trace_buffer *buffer, int cpu);
 713
 714struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
 715						struct trace_array_cpu *data);
 716
 717struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
 718					  int *ent_cpu, u64 *ent_ts);
 719
 720void trace_buffer_unlock_commit_nostack(struct trace_buffer *buffer,
 721					struct ring_buffer_event *event);
 722
 723bool trace_is_tracepoint_string(const char *str);
 724const char *trace_event_format(struct trace_iterator *iter, const char *fmt);
 725char *trace_iter_expand_format(struct trace_iterator *iter);
 726bool ignore_event(struct trace_iterator *iter);
 727
 728int trace_empty(struct trace_iterator *iter);
 729
 730void *trace_find_next_entry_inc(struct trace_iterator *iter);
 731
 732void trace_init_global_iter(struct trace_iterator *iter);
 733
 734void tracing_iter_reset(struct trace_iterator *iter, int cpu);
 735
 736unsigned long trace_total_entries_cpu(struct trace_array *tr, int cpu);
 737unsigned long trace_total_entries(struct trace_array *tr);
 738
 739void trace_function(struct trace_array *tr,
 740		    unsigned long ip,
 741		    unsigned long parent_ip,
 742		    unsigned int trace_ctx,
 743		    struct ftrace_regs *regs);
 744void trace_graph_function(struct trace_array *tr,
 745		    unsigned long ip,
 746		    unsigned long parent_ip,
 747		    unsigned int trace_ctx);
 748void trace_latency_header(struct seq_file *m);
 749void trace_default_header(struct seq_file *m);
 750void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
 751
 752void trace_graph_return(struct ftrace_graph_ret *trace, struct fgraph_ops *gops,
 753			struct ftrace_regs *fregs);
 754int trace_graph_entry(struct ftrace_graph_ent *trace, struct fgraph_ops *gops,
 755		      struct ftrace_regs *fregs);
 756
 757void tracing_start_cmdline_record(void);
 758void tracing_stop_cmdline_record(void);
 759void tracing_start_tgid_record(void);
 760void tracing_stop_tgid_record(void);
 761
 762int register_tracer(struct tracer *type);
 763int is_tracing_stopped(void);
 764
 765loff_t tracing_lseek(struct file *file, loff_t offset, int whence);
 766
 767extern cpumask_var_t __read_mostly tracing_buffer_mask;
 768
 769#define for_each_tracing_cpu(cpu)	\
 770	for_each_cpu(cpu, tracing_buffer_mask)
 771
 772extern unsigned long nsecs_to_usecs(unsigned long nsecs);
 773
 774extern unsigned long tracing_thresh;
 775
 776/* PID filtering */
 777
 778bool trace_find_filtered_pid(struct trace_pid_list *filtered_pids,
 779			     pid_t search_pid);
 780bool trace_ignore_this_task(struct trace_pid_list *filtered_pids,
 781			    struct trace_pid_list *filtered_no_pids,
 782			    struct task_struct *task);
 783void trace_filter_add_remove_task(struct trace_pid_list *pid_list,
 784				  struct task_struct *self,
 785				  struct task_struct *task);
 786void *trace_pid_next(struct trace_pid_list *pid_list, void *v, loff_t *pos);
 787void *trace_pid_start(struct trace_pid_list *pid_list, loff_t *pos);
 788int trace_pid_show(struct seq_file *m, void *v);
 789int trace_pid_write(struct trace_pid_list *filtered_pids,
 790		    struct trace_pid_list **new_pid_list,
 791		    const char __user *ubuf, size_t cnt);
 792
 793#ifdef CONFIG_TRACER_MAX_TRACE
 794void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu,
 795		   void *cond_data);
 796void update_max_tr_single(struct trace_array *tr,
 797			  struct task_struct *tsk, int cpu);
 798
 799#ifdef CONFIG_FSNOTIFY
 800#define LATENCY_FS_NOTIFY
 801#endif
 802#endif /* CONFIG_TRACER_MAX_TRACE */
 803
 804#ifdef LATENCY_FS_NOTIFY
 805void latency_fsnotify(struct trace_array *tr);
 806#else
 807static inline void latency_fsnotify(struct trace_array *tr) { }
 808#endif
 809
 810#ifdef CONFIG_STACKTRACE
 811void __trace_stack(struct trace_array *tr, unsigned int trace_ctx, int skip);
 812#else
 813static inline void __trace_stack(struct trace_array *tr, unsigned int trace_ctx,
 814				 int skip)
 815{
 816}
 817#endif /* CONFIG_STACKTRACE */
 818
 819void trace_last_func_repeats(struct trace_array *tr,
 820			     struct trace_func_repeats *last_info,
 821			     unsigned int trace_ctx);
 822
 823extern u64 ftrace_now(int cpu);
 824
 825extern void trace_find_cmdline(int pid, char comm[]);
 826extern int trace_find_tgid(int pid);
 827extern void trace_event_follow_fork(struct trace_array *tr, bool enable);
 828
 829extern int trace_events_enabled(struct trace_array *tr, const char *system);
 830
 831#ifdef CONFIG_DYNAMIC_FTRACE
 832extern unsigned long ftrace_update_tot_cnt;
 833extern unsigned long ftrace_number_of_pages;
 834extern unsigned long ftrace_number_of_groups;
 835extern u64 ftrace_update_time;
 836extern u64 ftrace_total_mod_time;
 837void ftrace_init_trace_array(struct trace_array *tr);
 838#else
 839static inline void ftrace_init_trace_array(struct trace_array *tr) { }
 840#endif
 841#define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
 842extern int DYN_FTRACE_TEST_NAME(void);
 843#define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
 844extern int DYN_FTRACE_TEST_NAME2(void);
 845
 846extern void trace_set_ring_buffer_expanded(struct trace_array *tr);
 847extern bool tracing_selftest_disabled;
 848
 849#ifdef CONFIG_FTRACE_STARTUP_TEST
 850extern void __init disable_tracing_selftest(const char *reason);
 851
 852extern int trace_selftest_startup_function(struct tracer *trace,
 853					   struct trace_array *tr);
 854extern int trace_selftest_startup_function_graph(struct tracer *trace,
 855						 struct trace_array *tr);
 856extern int trace_selftest_startup_irqsoff(struct tracer *trace,
 857					  struct trace_array *tr);
 858extern int trace_selftest_startup_preemptoff(struct tracer *trace,
 859					     struct trace_array *tr);
 860extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
 861						 struct trace_array *tr);
 862extern int trace_selftest_startup_wakeup(struct tracer *trace,
 863					 struct trace_array *tr);
 864extern int trace_selftest_startup_nop(struct tracer *trace,
 865					 struct trace_array *tr);
 866extern int trace_selftest_startup_branch(struct tracer *trace,
 867					 struct trace_array *tr);
 868/*
 869 * Tracer data references selftest functions that only occur
 870 * on boot up. These can be __init functions. Thus, when selftests
 871 * are enabled, then the tracers need to reference __init functions.
 872 */
 873#define __tracer_data		__refdata
 874#else
 875static inline void __init disable_tracing_selftest(const char *reason)
 876{
 877}
 878/* Tracers are seldom changed. Optimize when selftests are disabled. */
 879#define __tracer_data		__read_mostly
 880#endif /* CONFIG_FTRACE_STARTUP_TEST */
 881
 882extern void *head_page(struct trace_array_cpu *data);
 883extern unsigned long long ns2usecs(u64 nsec);
 884
 885__printf(2, 0)
 886int trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
 887__printf(2, 0)
 888int trace_vprintk(unsigned long ip, const char *fmt, va_list args);
 889__printf(3, 0)
 890int trace_array_vprintk(struct trace_array *tr,
 891			unsigned long ip, const char *fmt, va_list args);
 892__printf(3, 4)
 893int trace_array_printk_buf(struct trace_buffer *buffer,
 894			   unsigned long ip, const char *fmt, ...);
 895void trace_printk_seq(struct trace_seq *s);
 896enum print_line_t print_trace_line(struct trace_iterator *iter);
 897
 898extern char trace_find_mark(unsigned long long duration);
 899
 900struct ftrace_hash;
 901
 902struct ftrace_mod_load {
 903	struct list_head	list;
 904	char			*func;
 905	char			*module;
 906	int			 enable;
 907};
 908
 909enum {
 910	FTRACE_HASH_FL_MOD	= (1 << 0),
 911};
 912
 913struct ftrace_hash {
 914	unsigned long		size_bits;
 915	struct hlist_head	*buckets;
 916	unsigned long		count;
 917	unsigned long		flags;
 918	struct rcu_head		rcu;
 919};
 920
 921struct ftrace_func_entry *
 922ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip);
 923
 924static __always_inline bool ftrace_hash_empty(struct ftrace_hash *hash)
 925{
 926	return !hash || !(hash->count || (hash->flags & FTRACE_HASH_FL_MOD));
 927}
 928
 929/* Standard output formatting function used for function return traces */
 930#ifdef CONFIG_FUNCTION_GRAPH_TRACER
 931
 932/* Flag options */
 933#define TRACE_GRAPH_PRINT_OVERRUN       0x1
 934#define TRACE_GRAPH_PRINT_CPU           0x2
 935#define TRACE_GRAPH_PRINT_OVERHEAD      0x4
 936#define TRACE_GRAPH_PRINT_PROC          0x8
 937#define TRACE_GRAPH_PRINT_DURATION      0x10
 938#define TRACE_GRAPH_PRINT_ABS_TIME      0x20
 939#define TRACE_GRAPH_PRINT_REL_TIME      0x40
 940#define TRACE_GRAPH_PRINT_IRQS          0x80
 941#define TRACE_GRAPH_PRINT_TAIL          0x100
 942#define TRACE_GRAPH_SLEEP_TIME          0x200
 943#define TRACE_GRAPH_GRAPH_TIME          0x400
 944#define TRACE_GRAPH_PRINT_RETVAL        0x800
 945#define TRACE_GRAPH_PRINT_RETVAL_HEX    0x1000
 946#define TRACE_GRAPH_PRINT_RETADDR       0x2000
 947#define TRACE_GRAPH_ARGS		0x4000
 948#define TRACE_GRAPH_PRINT_FILL_SHIFT	28
 949#define TRACE_GRAPH_PRINT_FILL_MASK	(0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT)
 950
 951#ifdef CONFIG_FUNCTION_PROFILER
 952extern void ftrace_graph_graph_time_control(bool enable);
 953#else
 954static inline void ftrace_graph_graph_time_control(bool enable) { }
 955#endif
 956
 957extern enum print_line_t
 958print_graph_function_flags(struct trace_iterator *iter, u32 flags);
 959extern void print_graph_headers_flags(struct seq_file *s, u32 flags);
 960extern void
 961trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
 962extern void graph_trace_open(struct trace_iterator *iter);
 963extern void graph_trace_close(struct trace_iterator *iter);
 964extern int __trace_graph_entry(struct trace_array *tr,
 965			       struct ftrace_graph_ent *trace,
 966			       unsigned int trace_ctx);
 967extern int __trace_graph_retaddr_entry(struct trace_array *tr,
 968				struct ftrace_graph_ent *trace,
 969				unsigned int trace_ctx,
 970				unsigned long retaddr,
 971				struct ftrace_regs *fregs);
 972extern void __trace_graph_return(struct trace_array *tr,
 973				 struct ftrace_graph_ret *trace,
 974				 unsigned int trace_ctx,
 975				 u64 calltime, u64 rettime);
 976
 977extern void init_array_fgraph_ops(struct trace_array *tr, struct ftrace_ops *ops);
 978extern int allocate_fgraph_ops(struct trace_array *tr, struct ftrace_ops *ops);
 979extern void free_fgraph_ops(struct trace_array *tr);
 980
 981enum {
 982	TRACE_GRAPH_FL		= 1,
 983
 984	/*
 985	 * In the very unlikely case that an interrupt came in
 986	 * at a start of graph tracing, and we want to trace
 987	 * the function in that interrupt, the depth can be greater
 988	 * than zero, because of the preempted start of a previous
 989	 * trace. In an even more unlikely case, depth could be 2
 990	 * if a softirq interrupted the start of graph tracing,
 991	 * followed by an interrupt preempting a start of graph
 992	 * tracing in the softirq, and depth can even be 3
 993	 * if an NMI came in at the start of an interrupt function
 994	 * that preempted a softirq start of a function that
 995	 * preempted normal context!!!! Luckily, it can't be
 996	 * greater than 3, so the next two bits are a mask
 997	 * of what the depth is when we set TRACE_GRAPH_FL
 998	 */
 999
1000	TRACE_GRAPH_DEPTH_START_BIT,
1001	TRACE_GRAPH_DEPTH_END_BIT,
1002
1003	/*
1004	 * To implement set_graph_notrace, if this bit is set, we ignore
1005	 * function graph tracing of called functions, until the return
1006	 * function is called to clear it.
1007	 */
1008	TRACE_GRAPH_NOTRACE_BIT,
1009};
1010
1011#define TRACE_GRAPH_NOTRACE		(1 << TRACE_GRAPH_NOTRACE_BIT)
1012
1013static inline unsigned long ftrace_graph_depth(unsigned long *task_var)
1014{
1015	return (*task_var >> TRACE_GRAPH_DEPTH_START_BIT) & 3;
1016}
1017
1018static inline void ftrace_graph_set_depth(unsigned long *task_var, int depth)
1019{
1020	*task_var &= ~(3 << TRACE_GRAPH_DEPTH_START_BIT);
1021	*task_var |= (depth & 3) << TRACE_GRAPH_DEPTH_START_BIT;
1022}
1023
1024#ifdef CONFIG_DYNAMIC_FTRACE
1025extern struct ftrace_hash __rcu *ftrace_graph_hash;
1026extern struct ftrace_hash __rcu *ftrace_graph_notrace_hash;
1027
1028static inline int
1029ftrace_graph_addr(unsigned long *task_var, struct ftrace_graph_ent *trace)
1030{
1031	unsigned long addr = trace->func;
1032	int ret = 0;
1033	struct ftrace_hash *hash;
1034
1035	preempt_disable_notrace();
1036
1037	/*
1038	 * Have to open code "rcu_dereference_sched()" because the
1039	 * function graph tracer can be called when RCU is not
1040	 * "watching".
1041	 * Protected with schedule_on_each_cpu(ftrace_sync)
1042	 */
1043	hash = rcu_dereference_protected(ftrace_graph_hash, !preemptible());
1044
1045	if (ftrace_hash_empty(hash)) {
1046		ret = 1;
1047		goto out;
1048	}
1049
1050	if (ftrace_lookup_ip(hash, addr)) {
1051		/*
1052		 * This needs to be cleared on the return functions
1053		 * when the depth is zero.
1054		 */
1055		*task_var |= TRACE_GRAPH_FL;
1056		ftrace_graph_set_depth(task_var, trace->depth);
1057
1058		/*
1059		 * If no irqs are to be traced, but a set_graph_function
1060		 * is set, and called by an interrupt handler, we still
1061		 * want to trace it.
1062		 */
1063		if (in_hardirq())
1064			trace_recursion_set(TRACE_IRQ_BIT);
1065		else
1066			trace_recursion_clear(TRACE_IRQ_BIT);
1067		ret = 1;
1068	}
1069
1070out:
1071	preempt_enable_notrace();
1072	return ret;
1073}
1074
1075static inline void
1076ftrace_graph_addr_finish(struct fgraph_ops *gops, struct ftrace_graph_ret *trace)
1077{
1078	unsigned long *task_var = fgraph_get_task_var(gops);
1079
1080	if ((*task_var & TRACE_GRAPH_FL) &&
1081	    trace->depth == ftrace_graph_depth(task_var))
1082		*task_var &= ~TRACE_GRAPH_FL;
1083}
1084
1085static inline int ftrace_graph_notrace_addr(unsigned long addr)
1086{
1087	int ret = 0;
1088	struct ftrace_hash *notrace_hash;
1089
1090	preempt_disable_notrace();
1091
1092	/*
1093	 * Have to open code "rcu_dereference_sched()" because the
1094	 * function graph tracer can be called when RCU is not
1095	 * "watching".
1096	 * Protected with schedule_on_each_cpu(ftrace_sync)
1097	 */
1098	notrace_hash = rcu_dereference_protected(ftrace_graph_notrace_hash,
1099						 !preemptible());
1100
1101	if (ftrace_lookup_ip(notrace_hash, addr))
1102		ret = 1;
1103
1104	preempt_enable_notrace();
1105	return ret;
1106}
1107#else
1108static inline int ftrace_graph_addr(unsigned long *task_var, struct ftrace_graph_ent *trace)
1109{
1110	return 1;
1111}
1112
1113static inline int ftrace_graph_notrace_addr(unsigned long addr)
1114{
1115	return 0;
1116}
1117static inline void ftrace_graph_addr_finish(struct fgraph_ops *gops, struct ftrace_graph_ret *trace)
1118{ }
1119#endif /* CONFIG_DYNAMIC_FTRACE */
1120
1121extern unsigned int fgraph_max_depth;
1122extern int fgraph_no_sleep_time;
1123extern bool fprofile_no_sleep_time;
1124
1125static inline bool
1126ftrace_graph_ignore_func(struct fgraph_ops *gops, struct ftrace_graph_ent *trace)
1127{
1128	unsigned long *task_var = fgraph_get_task_var(gops);
1129
1130	/* trace it when it is-nested-in or is a function enabled. */
1131	return !((*task_var & TRACE_GRAPH_FL) ||
1132		 ftrace_graph_addr(task_var, trace)) ||
1133		(trace->depth < 0) ||
1134		(fgraph_max_depth && trace->depth >= fgraph_max_depth);
1135}
1136
1137void fgraph_init_ops(struct ftrace_ops *dst_ops,
1138		     struct ftrace_ops *src_ops);
1139
1140#else /* CONFIG_FUNCTION_GRAPH_TRACER */
1141static inline enum print_line_t
1142print_graph_function_flags(struct trace_iterator *iter, u32 flags)
1143{
1144	return TRACE_TYPE_UNHANDLED;
1145}
1146static inline void free_fgraph_ops(struct trace_array *tr) { }
1147/* ftrace_ops may not be defined */
1148#define init_array_fgraph_ops(tr, ops) do { } while (0)
1149#define allocate_fgraph_ops(tr, ops) ({ 0; })
1150#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
1151
1152extern struct list_head ftrace_pids;
1153
1154#ifdef CONFIG_FUNCTION_TRACER
1155
1156#define FTRACE_PID_IGNORE	-1
1157#define FTRACE_PID_TRACE	-2
1158
1159struct ftrace_func_command {
1160	struct list_head	list;
1161	char			*name;
1162	int			(*func)(struct trace_array *tr,
1163					struct ftrace_hash *hash,
1164					char *func, char *cmd,
1165					char *params, int enable);
1166};
1167extern bool ftrace_filter_param __initdata;
1168extern int ftrace_is_dead(void);
1169int ftrace_create_function_files(struct trace_array *tr,
1170				 struct dentry *parent);
1171void ftrace_destroy_function_files(struct trace_array *tr);
1172int ftrace_allocate_ftrace_ops(struct trace_array *tr);
1173void ftrace_free_ftrace_ops(struct trace_array *tr);
1174void ftrace_init_global_array_ops(struct trace_array *tr);
1175struct trace_array *trace_get_global_array(void);
1176void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func);
1177void ftrace_reset_array_ops(struct trace_array *tr);
1178void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer);
1179void ftrace_init_tracefs_toplevel(struct trace_array *tr,
1180				  struct dentry *d_tracer);
1181void ftrace_clear_pids(struct trace_array *tr);
1182int init_function_trace(void);
1183void ftrace_pid_follow_fork(struct trace_array *tr, bool enable);
1184#else
1185static inline int ftrace_is_dead(void) { return 0; }
1186static inline int
1187ftrace_create_function_files(struct trace_array *tr,
1188			     struct dentry *parent)
1189{
1190	return 0;
1191}
1192static inline int ftrace_allocate_ftrace_ops(struct trace_array *tr)
1193{
1194	return 0;
1195}
1196static inline void ftrace_free_ftrace_ops(struct trace_array *tr) { }
1197static inline void ftrace_destroy_function_files(struct trace_array *tr) { }
1198static inline __init void
1199ftrace_init_global_array_ops(struct trace_array *tr) { }
1200static inline void ftrace_reset_array_ops(struct trace_array *tr) { }
1201static inline void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d) { }
1202static inline void ftrace_init_tracefs_toplevel(struct trace_array *tr, struct dentry *d) { }
1203static inline void ftrace_clear_pids(struct trace_array *tr) { }
1204static inline int init_function_trace(void) { return 0; }
1205static inline void ftrace_pid_follow_fork(struct trace_array *tr, bool enable) { }
1206/* ftace_func_t type is not defined, use macro instead of static inline */
1207#define ftrace_init_array_ops(tr, func) do { } while (0)
1208#endif /* CONFIG_FUNCTION_TRACER */
1209
1210#if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE)
1211
1212struct ftrace_probe_ops {
1213	void			(*func)(unsigned long ip,
1214					unsigned long parent_ip,
1215					struct trace_array *tr,
1216					struct ftrace_probe_ops *ops,
1217					void *data);
1218	int			(*init)(struct ftrace_probe_ops *ops,
1219					struct trace_array *tr,
1220					unsigned long ip, void *init_data,
1221					void **data);
1222	void			(*free)(struct ftrace_probe_ops *ops,
1223					struct trace_array *tr,
1224					unsigned long ip, void *data);
1225	int			(*print)(struct seq_file *m,
1226					 unsigned long ip,
1227					 struct ftrace_probe_ops *ops,
1228					 void *data);
1229};
1230
1231struct ftrace_func_mapper;
1232typedef int (*ftrace_mapper_func)(void *data);
1233
1234struct ftrace_func_mapper *allocate_ftrace_func_mapper(void);
1235void **ftrace_func_mapper_find_ip(struct ftrace_func_mapper *mapper,
1236					   unsigned long ip);
1237int ftrace_func_mapper_add_ip(struct ftrace_func_mapper *mapper,
1238			       unsigned long ip, void *data);
1239void *ftrace_func_mapper_remove_ip(struct ftrace_func_mapper *mapper,
1240				   unsigned long ip);
1241void free_ftrace_func_mapper(struct ftrace_func_mapper *mapper,
1242			     ftrace_mapper_func free_func);
1243
1244extern int
1245register_ftrace_function_probe(char *glob, struct trace_array *tr,
1246			       struct ftrace_probe_ops *ops, void *data);
1247extern int
1248unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr,
1249				      struct ftrace_probe_ops *ops);
1250extern void clear_ftrace_function_probes(struct trace_array *tr);
1251
1252int register_ftrace_command(struct ftrace_func_command *cmd);
1253int unregister_ftrace_command(struct ftrace_func_command *cmd);
1254
1255void ftrace_create_filter_files(struct ftrace_ops *ops,
1256				struct dentry *parent);
1257void ftrace_destroy_filter_files(struct ftrace_ops *ops);
1258
1259extern int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf,
1260			     int len, int reset);
1261extern int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,
1262			      int len, int reset);
1263#else
1264struct ftrace_func_command;
1265
1266static inline __init int register_ftrace_command(struct ftrace_func_command *cmd)
1267{
1268	return -EINVAL;
1269}
1270static inline __init int unregister_ftrace_command(char *cmd_name)
1271{
1272	return -EINVAL;
1273}
1274static inline void clear_ftrace_function_probes(struct trace_array *tr)
1275{
1276}
1277
1278/*
1279 * The ops parameter passed in is usually undefined.
1280 * This must be a macro.
1281 */
1282#define ftrace_create_filter_files(ops, parent) do { } while (0)
1283#define ftrace_destroy_filter_files(ops) do { } while (0)
1284#endif /* CONFIG_FUNCTION_TRACER && CONFIG_DYNAMIC_FTRACE */
1285
1286bool ftrace_event_is_function(struct trace_event_call *call);
1287
1288/*
1289 * struct trace_parser - servers for reading the user input separated by spaces
1290 * @cont: set if the input is not complete - no final space char was found
1291 * @buffer: holds the parsed user input
1292 * @idx: user input length
1293 * @size: buffer size
1294 */
1295struct trace_parser {
1296	bool		cont;
1297	bool		fail;
1298	char		*buffer;
1299	unsigned	idx;
1300	unsigned	size;
1301};
1302
1303static inline bool trace_parser_loaded(struct trace_parser *parser)
1304{
1305	return !parser->fail && parser->idx != 0;
1306}
1307
1308static inline bool trace_parser_cont(struct trace_parser *parser)
1309{
1310	return parser->cont;
1311}
1312
1313static inline void trace_parser_clear(struct trace_parser *parser)
1314{
1315	parser->cont = false;
1316	parser->idx = 0;
1317}
1318
1319static inline void trace_parser_fail(struct trace_parser *parser)
1320{
1321	parser->fail = true;
1322}
1323
1324extern int trace_parser_get_init(struct trace_parser *parser, int size);
1325extern void trace_parser_put(struct trace_parser *parser);
1326extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
1327	size_t cnt, loff_t *ppos);
1328
1329/*
1330 * Only create function graph options if function graph is configured.
1331 */
1332#ifdef CONFIG_FUNCTION_GRAPH_TRACER
1333# define FGRAPH_FLAGS						\
1334		C(DISPLAY_GRAPH,	"display-graph"),
1335#else
1336# define FGRAPH_FLAGS
1337#endif
1338
1339#ifdef CONFIG_BRANCH_TRACER
1340# define BRANCH_FLAGS					\
1341		C(BRANCH,		"branch"),
1342#else
1343# define BRANCH_FLAGS
1344#endif
1345
1346#ifdef CONFIG_FUNCTION_TRACER
1347# define FUNCTION_FLAGS						\
1348		C(FUNCTION,		"function-trace"),	\
1349		C(FUNC_FORK,		"function-fork"),
1350# define FUNCTION_DEFAULT_FLAGS		TRACE_ITER(FUNCTION)
1351#else
1352# define FUNCTION_FLAGS
1353# define FUNCTION_DEFAULT_FLAGS		0UL
1354# define TRACE_ITER_FUNC_FORK_BIT	-1
1355#endif
1356
1357#ifdef CONFIG_STACKTRACE
1358# define STACK_FLAGS				\
1359		C(STACKTRACE,		"stacktrace"),
1360#else
1361# define STACK_FLAGS
1362#endif
1363
1364#ifdef CONFIG_FUNCTION_PROFILER
1365# define PROFILER_FLAGS					\
1366		C(PROF_TEXT_OFFSET,	"prof-text-offset"),
1367# ifdef CONFIG_FUNCTION_GRAPH_TRACER
1368#  define FPROFILE_FLAGS				\
1369		C(GRAPH_TIME,		"graph-time"),
1370#  define FPROFILE_DEFAULT_FLAGS	TRACE_ITER(GRAPH_TIME)
1371# else
1372#  define FPROFILE_FLAGS
1373#  define FPROFILE_DEFAULT_FLAGS	0UL
1374# endif
1375#else
1376# define PROFILER_FLAGS
1377# define FPROFILE_FLAGS
1378# define FPROFILE_DEFAULT_FLAGS			0UL
1379# define TRACE_ITER_PROF_TEXT_OFFSET_BIT	-1
1380#endif
1381
1382/*
1383 * trace_iterator_flags is an enumeration that defines bit
1384 * positions into trace_flags that controls the output.
1385 *
1386 * NOTE: These bits must match the trace_options array in
1387 *       trace.c (this macro guarantees it).
1388 */
1389#define TRACE_FLAGS						\
1390		C(PRINT_PARENT,		"print-parent"),	\
1391		C(SYM_OFFSET,		"sym-offset"),		\
1392		C(SYM_ADDR,		"sym-addr"),		\
1393		C(VERBOSE,		"verbose"),		\
1394		C(RAW,			"raw"),			\
1395		C(HEX,			"hex"),			\
1396		C(BIN,			"bin"),			\
1397		C(BLOCK,		"block"),		\
1398		C(FIELDS,		"fields"),		\
1399		C(PRINTK,		"trace_printk"),	\
1400		C(ANNOTATE,		"annotate"),		\
1401		C(USERSTACKTRACE,	"userstacktrace"),	\
1402		C(SYM_USEROBJ,		"sym-userobj"),		\
1403		C(PRINTK_MSGONLY,	"printk-msg-only"),	\
1404		C(CONTEXT_INFO,		"context-info"),   /* Print pid/cpu/time */ \
1405		C(LATENCY_FMT,		"latency-format"),	\
1406		C(RECORD_CMD,		"record-cmd"),		\
1407		C(RECORD_TGID,		"record-tgid"),		\
1408		C(OVERWRITE,		"overwrite"),		\
1409		C(STOP_ON_FREE,		"disable_on_free"),	\
1410		C(IRQ_INFO,		"irq-info"),		\
1411		C(MARKERS,		"markers"),		\
1412		C(EVENT_FORK,		"event-fork"),		\
1413		C(TRACE_PRINTK,		"trace_printk_dest"),	\
1414		C(COPY_MARKER,		"copy_trace_marker"),	\
1415		C(PAUSE_ON_TRACE,	"pause-on-trace"),	\
1416		C(HASH_PTR,		"hash-ptr"),	/* Print hashed pointer */ \
1417		FUNCTION_FLAGS					\
1418		FGRAPH_FLAGS					\
1419		STACK_FLAGS					\
1420		BRANCH_FLAGS					\
1421		PROFILER_FLAGS					\
1422		FPROFILE_FLAGS
1423
1424/*
1425 * By defining C, we can make TRACE_FLAGS a list of bit names
1426 * that will define the bits for the flag masks.
1427 */
1428#undef C
1429#define C(a, b) TRACE_ITER_##a##_BIT
1430
1431enum trace_iterator_bits {
1432	TRACE_FLAGS
1433	/* Make sure we don't go more than we have bits for */
1434	TRACE_ITER_LAST_BIT
1435};
1436
1437/*
1438 * And use TRACE_ITER(flag) to define the bit masks.
1439 */
1440#define TRACE_ITER(flag)		\
1441	(TRACE_ITER_##flag##_BIT < 0 ? 0 : 1ULL << (TRACE_ITER_##flag##_BIT))
1442
1443/*
1444 * TRACE_ITER_SYM_MASK masks the options in trace_flags that
1445 * control the output of kernel symbols.
1446 */
1447#define TRACE_ITER_SYM_MASK \
1448	(TRACE_ITER(PRINT_PARENT)|TRACE_ITER(SYM_OFFSET)|TRACE_ITER(SYM_ADDR))
1449
1450extern struct tracer nop_trace;
1451
1452#ifdef CONFIG_BRANCH_TRACER
1453extern int enable_branch_tracing(struct trace_array *tr);
1454extern void disable_branch_tracing(void);
1455static inline int trace_branch_enable(struct trace_array *tr)
1456{
1457	if (tr->trace_flags & TRACE_ITER(BRANCH))
1458		return enable_branch_tracing(tr);
1459	return 0;
1460}
1461static inline void trace_branch_disable(void)
1462{
1463	/* due to races, always disable */
1464	disable_branch_tracing();
1465}
1466#else
1467static inline int trace_branch_enable(struct trace_array *tr)
1468{
1469	return 0;
1470}
1471static inline void trace_branch_disable(void)
1472{
1473}
1474#endif /* CONFIG_BRANCH_TRACER */
1475
1476/* set ring buffers to default size if not already done so */
1477int tracing_update_buffers(struct trace_array *tr);
1478
1479union trace_synth_field {
1480	u8				as_u8;
1481	u16				as_u16;
1482	u32				as_u32;
1483	u64				as_u64;
1484	struct trace_dynamic_info	as_dynamic;
1485};
1486
1487struct ftrace_event_field {
1488	struct list_head	link;
1489	const char		*name;
1490	const char		*type;
1491	int			filter_type;
1492	int			offset;
1493	int			size;
1494	unsigned int		is_signed:1;
1495	unsigned int		needs_test:1;
1496	int			len;
1497};
1498
1499struct prog_entry;
1500
1501struct event_filter {
1502	struct prog_entry __rcu	*prog;
1503	char			*filter_string;
1504};
1505
1506struct event_subsystem {
1507	struct list_head	list;
1508	const char		*name;
1509	struct event_filter	*filter;
1510	int			ref_count;
1511};
1512
1513struct trace_subsystem_dir {
1514	struct list_head		list;
1515	struct event_subsystem		*subsystem;
1516	struct trace_array		*tr;
1517	struct eventfs_inode		*ei;
1518	int				ref_count;
1519	int				nr_events;
1520};
1521
1522void trace_buffer_unlock_commit_regs(struct trace_array *tr,
1523				     struct trace_buffer *buffer,
1524				     struct ring_buffer_event *event,
1525				     unsigned int trcace_ctx,
1526				     struct pt_regs *regs);
1527
1528static inline void trace_buffer_unlock_commit(struct trace_array *tr,
1529					      struct trace_buffer *buffer,
1530					      struct ring_buffer_event *event,
1531					      unsigned int trace_ctx)
1532{
1533	trace_buffer_unlock_commit_regs(tr, buffer, event, trace_ctx, NULL);
1534}
1535
1536DECLARE_PER_CPU(bool, trace_taskinfo_save);
1537int trace_save_cmdline(struct task_struct *tsk);
1538int trace_create_savedcmd(void);
1539int trace_alloc_tgid_map(void);
1540void trace_free_saved_cmdlines_buffer(void);
1541
1542extern const struct file_operations tracing_saved_cmdlines_fops;
1543extern const struct file_operations tracing_saved_tgids_fops;
1544extern const struct file_operations tracing_saved_cmdlines_size_fops;
1545
1546DECLARE_PER_CPU(struct ring_buffer_event *, trace_buffered_event);
1547DECLARE_PER_CPU(int, trace_buffered_event_cnt);
1548void trace_buffered_event_disable(void);
1549void trace_buffered_event_enable(void);
1550
1551void early_enable_events(struct trace_array *tr, char *buf, bool disable_first);
1552
1553struct trace_user_buf;
1554struct trace_user_buf_info {
1555	struct trace_user_buf __percpu	*tbuf;
1556	size_t				size;
1557	int				ref;
1558};
1559
1560typedef int (*trace_user_buf_copy)(char *dst, const char __user *src,
1561				  size_t size, void *data);
1562int trace_user_fault_init(struct trace_user_buf_info *tinfo, size_t size);
1563int trace_user_fault_get(struct trace_user_buf_info *tinfo);
1564int trace_user_fault_put(struct trace_user_buf_info *tinfo);
1565void trace_user_fault_destroy(struct trace_user_buf_info *tinfo);
1566char *trace_user_fault_read(struct trace_user_buf_info *tinfo,
1567			    const char __user *ptr, size_t size,
1568			    trace_user_buf_copy copy_func, void *data);
1569
1570static inline void
1571__trace_event_discard_commit(struct trace_buffer *buffer,
1572			     struct ring_buffer_event *event)
1573{
1574	if (this_cpu_read(trace_buffered_event) == event) {
1575		/* Simply release the temp buffer and enable preemption */
1576		this_cpu_dec(trace_buffered_event_cnt);
1577		preempt_enable_notrace();
1578		return;
1579	}
1580	/* ring_buffer_discard_commit() enables preemption */
1581	ring_buffer_discard_commit(buffer, event);
1582}
1583
1584/*
1585 * Helper function for event_trigger_unlock_commit{_regs}().
1586 * If there are event triggers attached to this event that requires
1587 * filtering against its fields, then they will be called as the
1588 * entry already holds the field information of the current event.
1589 *
1590 * It also checks if the event should be discarded or not.
1591 * It is to be discarded if the event is soft disabled and the
1592 * event was only recorded to process triggers, or if the event
1593 * filter is active and this event did not match the filters.
1594 *
1595 * Returns true if the event is discarded, false otherwise.
1596 */
1597static inline bool
1598__event_trigger_test_discard(struct trace_event_file *file,
1599			     struct trace_buffer *buffer,
1600			     struct ring_buffer_event *event,
1601			     void *entry,
1602			     enum event_trigger_type *tt)
1603{
1604	unsigned long eflags = file->flags;
1605
1606	if (eflags & EVENT_FILE_FL_TRIGGER_COND)
1607		*tt = event_triggers_call(file, buffer, entry, event);
1608
1609	if (likely(!(file->flags & (EVENT_FILE_FL_SOFT_DISABLED |
1610				    EVENT_FILE_FL_FILTERED |
1611				    EVENT_FILE_FL_PID_FILTER))))
1612		return false;
1613
1614	if (file->flags & EVENT_FILE_FL_SOFT_DISABLED)
1615		goto discard;
1616
1617	if (file->flags & EVENT_FILE_FL_FILTERED &&
1618	    !filter_match_preds(file->filter, entry))
1619		goto discard;
1620
1621	if ((file->flags & EVENT_FILE_FL_PID_FILTER) &&
1622	    trace_event_ignore_this_pid(file))
1623		goto discard;
1624
1625	return false;
1626 discard:
1627	__trace_event_discard_commit(buffer, event);
1628	return true;
1629}
1630
1631/**
1632 * event_trigger_unlock_commit - handle triggers and finish event commit
1633 * @file: The file pointer associated with the event
1634 * @buffer: The ring buffer that the event is being written to
1635 * @event: The event meta data in the ring buffer
1636 * @entry: The event itself
1637 * @trace_ctx: The tracing context flags.
1638 *
1639 * This is a helper function to handle triggers that require data
1640 * from the event itself. It also tests the event against filters and
1641 * if the event is soft disabled and should be discarded.
1642 */
1643static inline void
1644event_trigger_unlock_commit(struct trace_event_file *file,
1645			    struct trace_buffer *buffer,
1646			    struct ring_buffer_event *event,
1647			    void *entry, unsigned int trace_ctx)
1648{
1649	enum event_trigger_type tt = ETT_NONE;
1650
1651	if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
1652		trace_buffer_unlock_commit(file->tr, buffer, event, trace_ctx);
1653
1654	if (tt)
1655		event_triggers_post_call(file, tt);
1656}
1657
1658#define FILTER_PRED_INVALID	((unsigned short)-1)
1659#define FILTER_PRED_IS_RIGHT	(1 << 15)
1660#define FILTER_PRED_FOLD	(1 << 15)
1661
1662/*
1663 * The max preds is the size of unsigned short with
1664 * two flags at the MSBs. One bit is used for both the IS_RIGHT
1665 * and FOLD flags. The other is reserved.
1666 *
1667 * 2^14 preds is way more than enough.
1668 */
1669#define MAX_FILTER_PRED		16384
1670
1671struct filter_pred;
1672struct regex;
1673
1674typedef int (*regex_match_func)(char *str, struct regex *r, int len);
1675
1676enum regex_type {
1677	MATCH_FULL = 0,
1678	MATCH_FRONT_ONLY,
1679	MATCH_MIDDLE_ONLY,
1680	MATCH_END_ONLY,
1681	MATCH_GLOB,
1682	MATCH_INDEX,
1683};
1684
1685struct regex {
1686	char			pattern[MAX_FILTER_STR_VAL];
1687	int			len;
1688	int			field_len;
1689	regex_match_func	match;
1690};
1691
1692static inline bool is_string_field(struct ftrace_event_field *field)
1693{
1694	return field->filter_type == FILTER_DYN_STRING ||
1695	       field->filter_type == FILTER_RDYN_STRING ||
1696	       field->filter_type == FILTER_STATIC_STRING ||
1697	       field->filter_type == FILTER_PTR_STRING ||
1698	       field->filter_type == FILTER_COMM;
1699}
1700
1701static inline bool is_function_field(struct ftrace_event_field *field)
1702{
1703	return field->filter_type == FILTER_TRACE_FN;
1704}
1705
1706extern enum regex_type
1707filter_parse_regex(char *buff, int len, char **search, int *not);
1708extern void print_event_filter(struct trace_event_file *file,
1709			       struct trace_seq *s);
1710extern int apply_event_filter(struct trace_event_file *file,
1711			      char *filter_string);
1712extern int apply_subsystem_event_filter(struct trace_subsystem_dir *dir,
1713					char *filter_string);
1714extern void print_subsystem_event_filter(struct event_subsystem *system,
1715					 struct trace_seq *s);
1716extern int filter_assign_type(const char *type);
1717extern int create_event_filter(struct trace_array *tr,
1718			       struct trace_event_call *call,
1719			       char *filter_str, bool set_str,
1720			       struct event_filter **filterp);
1721extern void free_event_filter(struct event_filter *filter);
1722
1723struct ftrace_event_field *
1724trace_find_event_field(struct trace_event_call *call, char *name);
1725
1726extern void trace_event_enable_cmd_record(bool enable);
1727extern void trace_event_enable_tgid_record(bool enable);
1728
1729extern int event_trace_init(void);
1730extern int init_events(void);
1731extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr);
1732extern int event_trace_del_tracer(struct trace_array *tr);
1733extern void __trace_early_add_events(struct trace_array *tr);
1734
1735extern struct trace_event_file *__find_event_file(struct trace_array *tr,
1736						  const char *system,
1737						  const char *event);
1738extern struct trace_event_file *find_event_file(struct trace_array *tr,
1739						const char *system,
1740						const char *event);
1741
1742static inline void *event_file_data(struct file *filp)
1743{
1744	return READ_ONCE(file_inode(filp)->i_private);
1745}
1746
1747extern struct mutex event_mutex;
1748extern struct list_head ftrace_events;
1749
1750/*
1751 * When the trace_event_file is the filp->i_private pointer,
1752 * it must be taken under the event_mutex lock, and then checked
1753 * if the EVENT_FILE_FL_FREED flag is set. If it is, then the
1754 * data pointed to by the trace_event_file can not be trusted.
1755 *
1756 * Use the event_file_file() to access the trace_event_file from
1757 * the filp the first time under the event_mutex and check for
1758 * NULL. If it is needed to be retrieved again and the event_mutex
1759 * is still held, then the event_file_data() can be used and it
1760 * is guaranteed to be valid.
1761 */
1762static inline struct trace_event_file *event_file_file(struct file *filp)
1763{
1764	struct trace_event_file *file;
1765
1766	lockdep_assert_held(&event_mutex);
1767	file = READ_ONCE(file_inode(filp)->i_private);
1768	if (!file || file->flags & EVENT_FILE_FL_FREED)
1769		return NULL;
1770	return file;
1771}
1772
1773extern const struct file_operations event_trigger_fops;
1774extern const struct file_operations event_hist_fops;
1775extern const struct file_operations event_hist_debug_fops;
1776extern const struct file_operations event_inject_fops;
1777
1778#ifdef CONFIG_HIST_TRIGGERS
1779extern int register_trigger_hist_cmd(void);
1780extern int register_trigger_hist_enable_disable_cmds(void);
1781#else
1782static inline int register_trigger_hist_cmd(void) { return 0; }
1783static inline int register_trigger_hist_enable_disable_cmds(void) { return 0; }
1784#endif
1785
1786extern int register_trigger_cmds(void);
1787extern void clear_event_triggers(struct trace_array *tr);
1788
1789enum {
1790	EVENT_TRIGGER_FL_PROBE		= BIT(0),
1791	EVENT_TRIGGER_FL_COUNT		= BIT(1),
1792};
1793
1794struct event_trigger_data {
1795	unsigned long			count;
1796	int				ref;
1797	int				flags;
1798	struct event_command		*cmd_ops;
1799	struct event_filter __rcu	*filter;
1800	char				*filter_str;
1801	void				*private_data;
1802	bool				paused;
1803	bool				paused_tmp;
1804	struct list_head		list;
1805	char				*name;
1806	struct list_head		named_list;
1807	struct event_trigger_data	*named_data;
1808	struct llist_node		llist;
1809};
1810
1811/* Avoid typos */
1812#define ENABLE_EVENT_STR	"enable_event"
1813#define DISABLE_EVENT_STR	"disable_event"
1814#define ENABLE_HIST_STR		"enable_hist"
1815#define DISABLE_HIST_STR	"disable_hist"
1816
1817struct enable_trigger_data {
1818	struct trace_event_file		*file;
1819	bool				enable;
1820	bool				hist;
1821};
1822
1823bool event_trigger_count(struct event_trigger_data *data,
1824			 struct trace_buffer *buffer,  void *rec,
1825			 struct ring_buffer_event *event);
1826
1827extern int event_enable_trigger_print(struct seq_file *m,
1828				      struct event_trigger_data *data);
1829extern void event_enable_trigger_free(struct event_trigger_data *data);
1830extern int event_enable_trigger_parse(struct event_command *cmd_ops,
1831				      struct trace_event_file *file,
1832				      char *glob, char *cmd,
1833				      char *param_and_filter);
1834extern int event_enable_register_trigger(char *glob,
1835					 struct event_trigger_data *data,
1836					 struct trace_event_file *file);
1837extern void event_enable_unregister_trigger(char *glob,
1838					    struct event_trigger_data *test,
1839					    struct trace_event_file *file);
1840extern struct event_trigger_data *
1841trigger_data_alloc(struct event_command *cmd_ops, char *cmd, char *param,
1842		   void *private_data);
1843extern void trigger_data_free(struct event_trigger_data *data);
1844extern int event_trigger_init(struct event_trigger_data *data);
1845extern int trace_event_trigger_enable_disable(struct trace_event_file *file,
1846					      int trigger_enable);
1847extern void update_cond_flag(struct trace_event_file *file);
1848extern int set_trigger_filter(char *filter_str,
1849			      struct event_trigger_data *trigger_data,
1850			      struct trace_event_file *file);
1851extern struct event_trigger_data *find_named_trigger(const char *name);
1852extern bool is_named_trigger(struct event_trigger_data *test);
1853extern int save_named_trigger(const char *name,
1854			      struct event_trigger_data *data);
1855extern void del_named_trigger(struct event_trigger_data *data);
1856extern void pause_named_trigger(struct event_trigger_data *data);
1857extern void unpause_named_trigger(struct event_trigger_data *data);
1858extern void set_named_trigger_data(struct event_trigger_data *data,
1859				   struct event_trigger_data *named_data);
1860extern struct event_trigger_data *
1861get_named_trigger_data(struct event_trigger_data *data);
1862extern int register_event_command(struct event_command *cmd);
1863extern int unregister_event_command(struct event_command *cmd);
1864extern int register_trigger_hist_enable_disable_cmds(void);
1865extern bool event_trigger_check_remove(const char *glob);
1866extern bool event_trigger_empty_param(const char *param);
1867extern int event_trigger_separate_filter(char *param_and_filter, char **param,
1868					 char **filter, bool param_required);
1869extern int event_trigger_parse_num(char *trigger,
1870				   struct event_trigger_data *trigger_data);
1871extern int event_trigger_set_filter(struct event_command *cmd_ops,
1872				    struct trace_event_file *file,
1873				    char *param,
1874				    struct event_trigger_data *trigger_data);
1875extern void event_trigger_reset_filter(struct event_command *cmd_ops,
1876				       struct event_trigger_data *trigger_data);
1877extern int event_trigger_register(struct event_command *cmd_ops,
1878				  struct trace_event_file *file,
1879				  char *glob,
1880				  struct event_trigger_data *trigger_data);
1881extern void event_trigger_unregister(struct event_command *cmd_ops,
1882				     struct trace_event_file *file,
1883				     char *glob,
1884				     struct event_trigger_data *trigger_data);
1885
1886extern void event_file_get(struct trace_event_file *file);
1887extern void event_file_put(struct trace_event_file *file);
1888
1889/**
1890 * struct event_command - callbacks and data members for event commands
1891 *
1892 * Event commands are invoked by users by writing the command name
1893 * into the 'trigger' file associated with a trace event.  The
1894 * parameters associated with a specific invocation of an event
1895 * command are used to create an event trigger instance, which is
1896 * added to the list of trigger instances associated with that trace
1897 * event.  When the event is hit, the set of triggers associated with
1898 * that event is invoked.
1899 *
1900 * The data members in this structure provide per-event command data
1901 * for various event commands.
1902 *
1903 * All the data members below, except for @post_trigger, must be set
1904 * for each event command.
1905 *
1906 * @name: The unique name that identifies the event command.  This is
1907 *	the name used when setting triggers via trigger files.
1908 *
1909 * @trigger_type: A unique id that identifies the event command
1910 *	'type'.  This value has two purposes, the first to ensure that
1911 *	only one trigger of the same type can be set at a given time
1912 *	for a particular event e.g. it doesn't make sense to have both
1913 *	a traceon and traceoff trigger attached to a single event at
1914 *	the same time, so traceon and traceoff have the same type
1915 *	though they have different names.  The @trigger_type value is
1916 *	also used as a bit value for deferring the actual trigger
1917 *	action until after the current event is finished.  Some
1918 *	commands need to do this if they themselves log to the trace
1919 *	buffer (see the @post_trigger() member below).  @trigger_type
1920 *	values are defined by adding new values to the trigger_type
1921 *	enum in include/linux/trace_events.h.
1922 *
1923 * @flags: See the enum event_command_flags below.
1924 *
1925 * All the methods below, except for @set_filter() and @unreg_all(),
1926 * must be implemented.
1927 *
1928 * @parse: The callback function responsible for parsing and
1929 *	registering the trigger written to the 'trigger' file by the
1930 *	user.  It allocates the trigger instance and registers it with
1931 *	the appropriate trace event.  It makes use of the other
1932 *	event_command callback functions to orchestrate this, and is
1933 *	usually implemented by the generic utility function
1934 *	@event_trigger_callback() (see trace_event_triggers.c).
1935 *
1936 * @reg: Adds the trigger to the list of triggers associated with the
1937 *	event, and enables the event trigger itself, after
1938 *	initializing it (via the event_command @init() function).
1939 *	This is also where commands can use the @trigger_type value to
1940 *	make the decision as to whether or not multiple instances of
1941 *	the trigger should be allowed.  This is usually implemented by
1942 *	the generic utility function @register_trigger() (see
1943 *	trace_event_triggers.c).
1944 *
1945 * @unreg: Removes the trigger from the list of triggers associated
1946 *	with the event, and disables the event trigger itself, after
1947 *	initializing it (via the event_command @free() function).
1948 *	This is usually implemented by the generic utility function
1949 *	@unregister_trigger() (see trace_event_triggers.c).
1950 *
1951 * @unreg_all: An optional function called to remove all the triggers
1952 *	from the list of triggers associated with the event.  Called
1953 *	when a trigger file is opened in truncate mode.
1954 *
1955 * @set_filter: An optional function called to parse and set a filter
1956 *	for the trigger.  If no @set_filter() method is set for the
1957 *	event command, filters set by the user for the command will be
1958 *	ignored.  This is usually implemented by the generic utility
1959 *	function @set_trigger_filter() (see trace_event_triggers.c).
1960 *
1961 * All the methods below, except for @init() and @free(), must be
1962 * implemented.
1963 *
1964 * @trigger: The trigger 'probe' function called when the triggering
1965 *	event occurs.  The data passed into this callback is the data
1966 *	that was supplied to the event_command @reg() function that
1967 *	registered the trigger (see struct event_command) along with
1968 *	the trace record, rec.
1969 *
1970 * @count_func: If defined and a numeric parameter is passed to the
1971 *	trigger, then this function will be called before @trigger
1972 *	is called. If this function returns false, then @trigger is not
1973 *	executed.
1974 *
1975 * @init: An optional initialization function called for the trigger
1976 *	when the trigger is registered (via the event_command reg()
1977 *	function).  This can be used to perform per-trigger
1978 *	initialization such as incrementing a per-trigger reference
1979 *	count, for instance.  This is usually implemented by the
1980 *	generic utility function @event_trigger_init() (see
1981 *	trace_event_triggers.c).
1982 *
1983 * @free: An optional de-initialization function called for the
1984 *	trigger when the trigger is unregistered (via the
1985 *	event_command @reg() function).  This can be used to perform
1986 *	per-trigger de-initialization such as decrementing a
1987 *	per-trigger reference count and freeing corresponding trigger
1988 *	data, for instance.  This is usually implemented by the
1989 *	generic utility function @event_trigger_free() (see
1990 *	trace_event_triggers.c).
1991 *
1992 * @print: The callback function invoked to have the trigger print
1993 *	itself.  This is usually implemented by a wrapper function
1994 *	that calls the generic utility function @event_trigger_print()
1995 *	(see trace_event_triggers.c).
1996 */
1997struct event_command {
1998	struct list_head	list;
1999	char			*name;
2000	enum event_trigger_type	trigger_type;
2001	int			flags;
2002	int			(*parse)(struct event_command *cmd_ops,
2003					 struct trace_event_file *file,
2004					 char *glob, char *cmd,
2005					 char *param_and_filter);
2006	int			(*reg)(char *glob,
2007				       struct event_trigger_data *data,
2008				       struct trace_event_file *file);
2009	void			(*unreg)(char *glob,
2010					 struct event_trigger_data *data,
2011					 struct trace_event_file *file);
2012	void			(*unreg_all)(struct trace_event_file *file);
2013	int			(*set_filter)(char *filter_str,
2014					      struct event_trigger_data *data,
2015					      struct trace_event_file *file);
2016	void			(*trigger)(struct event_trigger_data *data,
2017					   struct trace_buffer *buffer,
2018					   void *rec,
2019					   struct ring_buffer_event *rbe);
2020	bool			(*count_func)(struct event_trigger_data *data,
2021					      struct trace_buffer *buffer,
2022					      void *rec,
2023					      struct ring_buffer_event *rbe);
2024	int			(*init)(struct event_trigger_data *data);
2025	void			(*free)(struct event_trigger_data *data);
2026	int			(*print)(struct seq_file *m,
2027					 struct event_trigger_data *data);
2028};
2029
2030/**
2031 * enum event_command_flags - flags for struct event_command
2032 *
2033 * @POST_TRIGGER: A flag that says whether or not this command needs
2034 *	to have its action delayed until after the current event has
2035 *	been closed.  Some triggers need to avoid being invoked while
2036 *	an event is currently in the process of being logged, since
2037 *	the trigger may itself log data into the trace buffer.  Thus
2038 *	we make sure the current event is committed before invoking
2039 *	those triggers.  To do that, the trigger invocation is split
2040 *	in two - the first part checks the filter using the current
2041 *	trace record; if a command has the @post_trigger flag set, it
2042 *	sets a bit for itself in the return value, otherwise it
2043 *	directly invokes the trigger.  Once all commands have been
2044 *	either invoked or set their return flag, the current record is
2045 *	either committed or discarded.  At that point, if any commands
2046 *	have deferred their triggers, those commands are finally
2047 *	invoked following the close of the current event.  In other
2048 *	words, if the event_command @func() probe implementation
2049 *	itself logs to the trace buffer, this flag should be set,
2050 *	otherwise it can be left unspecified.
2051 *
2052 * @NEEDS_REC: A flag that says whether or not this command needs
2053 *	access to the trace record in order to perform its function,
2054 *	regardless of whether or not it has a filter associated with
2055 *	it (filters make a trigger require access to the trace record
2056 *	but are not always present).
2057 */
2058enum event_command_flags {
2059	EVENT_CMD_FL_POST_TRIGGER	= 1,
2060	EVENT_CMD_FL_NEEDS_REC		= 2,
2061};
2062
2063static inline bool event_command_post_trigger(struct event_command *cmd_ops)
2064{
2065	return cmd_ops->flags & EVENT_CMD_FL_POST_TRIGGER;
2066}
2067
2068static inline bool event_command_needs_rec(struct event_command *cmd_ops)
2069{
2070	return cmd_ops->flags & EVENT_CMD_FL_NEEDS_REC;
2071}
2072
2073extern int trace_event_enable_disable(struct trace_event_file *file,
2074				      int enable, int soft_disable);
2075extern int tracing_alloc_snapshot(void);
2076extern void tracing_snapshot_cond(struct trace_array *tr, void *cond_data);
2077extern int tracing_snapshot_cond_enable(struct trace_array *tr, void *cond_data, cond_update_fn_t update);
2078
2079extern int tracing_snapshot_cond_disable(struct trace_array *tr);
2080extern void *tracing_cond_snapshot_data(struct trace_array *tr);
2081
2082extern const char *__start___trace_bprintk_fmt[];
2083extern const char *__stop___trace_bprintk_fmt[];
2084
2085extern const char *__start___tracepoint_str[];
2086extern const char *__stop___tracepoint_str[];
2087
2088void trace_printk_control(bool enabled);
2089void trace_printk_start_comm(void);
2090int trace_keep_overwrite(struct tracer *tracer, u64 mask, int set);
2091int set_tracer_flag(struct trace_array *tr, u64 mask, int enabled);
2092
2093/* Used from boot time tracer */
2094extern int trace_set_options(struct trace_array *tr, char *option);
2095extern int tracing_set_tracer(struct trace_array *tr, const char *buf);
2096extern ssize_t tracing_resize_ring_buffer(struct trace_array *tr,
2097					  unsigned long size, int cpu_id);
2098extern int tracing_set_cpumask(struct trace_array *tr,
2099				cpumask_var_t tracing_cpumask_new);
2100
2101
2102#define MAX_EVENT_NAME_LEN	64
2103
2104extern ssize_t trace_parse_run_command(struct file *file,
2105		const char __user *buffer, size_t count, loff_t *ppos,
2106		int (*createfn)(const char *));
2107
2108extern unsigned int err_pos(char *cmd, const char *str);
2109extern void tracing_log_err(struct trace_array *tr,
2110			    const char *loc, const char *cmd,
2111			    const char **errs, u8 type, u16 pos);
2112
2113/*
2114 * Normal trace_printk() and friends allocates special buffers
2115 * to do the manipulation, as well as saves the print formats
2116 * into sections to display. But the trace infrastructure wants
2117 * to use these without the added overhead at the price of being
2118 * a bit slower (used mainly for warnings, where we don't care
2119 * about performance). The internal_trace_puts() is for such
2120 * a purpose.
2121 */
2122#define internal_trace_puts(str) __trace_puts(_THIS_IP_, str, strlen(str))
2123
2124#undef FTRACE_ENTRY
2125#define FTRACE_ENTRY(call, struct_name, id, tstruct, print)	\
2126	extern struct trace_event_call					\
2127	__aligned(4) event_##call;
2128#undef FTRACE_ENTRY_DUP
2129#define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print)	\
2130	FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
2131#undef FTRACE_ENTRY_PACKED
2132#define FTRACE_ENTRY_PACKED(call, struct_name, id, tstruct, print) \
2133	FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
2134
2135#include "trace_entries.h"
2136
2137#if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER)
2138int perf_ftrace_event_register(struct trace_event_call *call,
2139			       enum trace_reg type, void *data);
2140#else
2141#define perf_ftrace_event_register NULL
2142#endif
2143
2144#ifdef CONFIG_FTRACE_SYSCALLS
2145void init_ftrace_syscalls(void);
2146const char *get_syscall_name(int syscall);
2147#else
2148static inline void init_ftrace_syscalls(void) { }
2149static inline const char *get_syscall_name(int syscall)
2150{
2151	return NULL;
2152}
2153#endif
2154
2155#ifdef CONFIG_EVENT_TRACING
2156void trace_event_init(void);
2157void trace_event_update_all(struct trace_eval_map **map, int len);
2158/* Used from boot time tracer */
2159extern int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set);
2160extern int trigger_process_regex(struct trace_event_file *file, char *buff);
2161#else
2162static inline void __init trace_event_init(void) { }
2163static inline void trace_event_update_all(struct trace_eval_map **map, int len) { }
2164#endif
2165
2166#ifdef CONFIG_TRACER_SNAPSHOT
2167void tracing_snapshot_instance(struct trace_array *tr);
2168int tracing_alloc_snapshot_instance(struct trace_array *tr);
2169int tracing_arm_snapshot(struct trace_array *tr);
2170void tracing_disarm_snapshot(struct trace_array *tr);
2171#else
2172static inline void tracing_snapshot_instance(struct trace_array *tr) { }
2173static inline int tracing_alloc_snapshot_instance(struct trace_array *tr)
2174{
2175	return 0;
2176}
2177static inline int tracing_arm_snapshot(struct trace_array *tr) { return 0; }
2178static inline void tracing_disarm_snapshot(struct trace_array *tr) { }
2179#endif
2180
2181#ifdef CONFIG_PREEMPT_TRACER
2182void tracer_preempt_on(unsigned long a0, unsigned long a1);
2183void tracer_preempt_off(unsigned long a0, unsigned long a1);
2184#else
2185static inline void tracer_preempt_on(unsigned long a0, unsigned long a1) { }
2186static inline void tracer_preempt_off(unsigned long a0, unsigned long a1) { }
2187#endif
2188#ifdef CONFIG_IRQSOFF_TRACER
2189void tracer_hardirqs_on(unsigned long a0, unsigned long a1);
2190void tracer_hardirqs_off(unsigned long a0, unsigned long a1);
2191#else
2192static inline void tracer_hardirqs_on(unsigned long a0, unsigned long a1) { }
2193static inline void tracer_hardirqs_off(unsigned long a0, unsigned long a1) { }
2194#endif
2195
2196/*
2197 * Reset the state of the trace_iterator so that it can read consumed data.
2198 * Normally, the trace_iterator is used for reading the data when it is not
2199 * consumed, and must retain state.
2200 */
2201static __always_inline void trace_iterator_reset(struct trace_iterator *iter)
2202{
2203	memset_startat(iter, 0, seq);
2204	iter->pos = -1;
2205}
2206
2207/* Check the name is good for event/group/fields */
2208static inline bool __is_good_name(const char *name, bool hash_ok)
2209{
2210	if (!isalpha(*name) && *name != '_' && (!hash_ok || *name != '-'))
2211		return false;
2212	while (*++name != '\0') {
2213		if (!isalpha(*name) && !isdigit(*name) && *name != '_' &&
2214		    (!hash_ok || *name != '-'))
2215			return false;
2216	}
2217	return true;
2218}
2219
2220/* Check the name is good for event/group/fields */
2221static inline bool is_good_name(const char *name)
2222{
2223	return __is_good_name(name, false);
2224}
2225
2226/* Check the name is good for system */
2227static inline bool is_good_system_name(const char *name)
2228{
2229	return __is_good_name(name, true);
2230}
2231
2232/* Convert certain expected symbols into '_' when generating event names */
2233static inline void sanitize_event_name(char *name)
2234{
2235	while (*name++ != '\0')
2236		if (*name == ':' || *name == '.' || *name == '*')
2237			*name = '_';
2238}
2239
2240/*
2241 * This is a generic way to read and write a u64 value from a file in tracefs.
2242 *
2243 * The value is stored on the variable pointed by *val. The value needs
2244 * to be at least *min and at most *max. The write is protected by an
2245 * existing *lock.
2246 */
2247struct trace_min_max_param {
2248	struct mutex	*lock;
2249	u64		*val;
2250	u64		*min;
2251	u64		*max;
2252};
2253
2254#define U64_STR_SIZE		24	/* 20 digits max */
2255
2256extern const struct file_operations trace_min_max_fops;
2257
2258#ifdef CONFIG_RV
2259extern int rv_init_interface(void);
2260#else
2261static inline int rv_init_interface(void)
2262{
2263	return 0;
2264}
2265#endif
2266
2267/*
2268 * This is used only to distinguish
2269 * function address from trampoline code.
2270 * So this value has no meaning.
2271 */
2272#define FTRACE_TRAMPOLINE_MARKER  ((unsigned long) INT_MAX)
2273
2274/*
2275 * This is used to get the address of the args array based on
2276 * the type of the entry.
2277 */
2278#define FGRAPH_ENTRY_ARGS(e)						\
2279	({								\
2280		unsigned long *_args;					\
2281		struct ftrace_graph_ent_entry *_e = e;			\
2282									\
2283		if (IS_ENABLED(CONFIG_FUNCTION_GRAPH_RETADDR) &&	\
2284			e->ent.type == TRACE_GRAPH_RETADDR_ENT) {	\
2285			struct fgraph_retaddr_ent_entry *_re;		\
2286									\
2287			_re = (typeof(_re))_e;				\
2288			_args = _re->args;				\
2289		} else {						\
2290			_args = _e->args;				\
2291		}							\
2292		_args;							\
2293	})
2294
2295#endif /* _LINUX_KERNEL_TRACE_H */