1
   2#ifndef _LINUX_KERNEL_TRACE_H
   3#define _LINUX_KERNEL_TRACE_H
   4
   5#include <linux/fs.h>
   6#include <linux/atomic.h>
   7#include <linux/sched.h>
   8#include <linux/clocksource.h>
   9#include <linux/ring_buffer.h>
  10#include <linux/mmiotrace.h>
  11#include <linux/tracepoint.h>
  12#include <linux/ftrace.h>
 
  13#include <linux/hw_breakpoint.h>
  14#include <linux/trace_seq.h>
  15#include <linux/trace_events.h>
  16#include <linux/compiler.h>
  17#include <linux/trace_seq.h>
 
 
 
 
  18
  19#ifdef CONFIG_FTRACE_SYSCALLS
  20#include <asm/unistd.h>		/* For NR_SYSCALLS	     */
  21#include <asm/syscall.h>	/* some archs define it here */
  22#endif
  23
  24enum trace_type {
  25	__TRACE_FIRST_TYPE = 0,
  26
  27	TRACE_FN,
  28	TRACE_CTX,
  29	TRACE_WAKE,
  30	TRACE_STACK,
  31	TRACE_PRINT,
  32	TRACE_BPRINT,
  33	TRACE_MMIO_RW,
  34	TRACE_MMIO_MAP,
  35	TRACE_BRANCH,
  36	TRACE_GRAPH_RET,
  37	TRACE_GRAPH_ENT,
  38	TRACE_USER_STACK,
  39	TRACE_BLK,
  40	TRACE_BPUTS,
 
 
 
 
 
  41
  42	__TRACE_LAST_TYPE,
  43};
  44
  45
  46#undef __field
  47#define __field(type, item)		type	item;
  48
 
 
 
  49#undef __field_struct
  50#define __field_struct(type, item)	__field(type, item)
  51
  52#undef __field_desc
  53#define __field_desc(type, container, item)
  54
 
 
 
  55#undef __array
  56#define __array(type, item, size)	type	item[size];
  57
  58#undef __array_desc
  59#define __array_desc(type, container, item, size)
  60
  61#undef __dynamic_array
  62#define __dynamic_array(type, item)	type	item[];
  63
  64#undef F_STRUCT
  65#define F_STRUCT(args...)		args
  66
  67#undef FTRACE_ENTRY
  68#define FTRACE_ENTRY(name, struct_name, id, tstruct, print, filter)	\
  69	struct struct_name {						\
  70		struct trace_entry	ent;				\
  71		tstruct							\
  72	}
  73
  74#undef FTRACE_ENTRY_DUP
  75#define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk, filter)
  76
  77#undef FTRACE_ENTRY_REG
  78#define FTRACE_ENTRY_REG(name, struct_name, id, tstruct, print,	\
  79			 filter, regfn) \
  80	FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print), \
  81		     filter)
 
 
  82
  83#include "trace_entries.h"
  84
 
 
 
 
  85/*
  86 * syscalls are special, and need special handling, this is why
  87 * they are not included in trace_entries.h
  88 */
  89struct syscall_trace_enter {
  90	struct trace_entry	ent;
  91	int			nr;
  92	unsigned long		args[];
  93};
  94
  95struct syscall_trace_exit {
  96	struct trace_entry	ent;
  97	int			nr;
  98	long			ret;
  99};
 100
 101struct kprobe_trace_entry_head {
 102	struct trace_entry	ent;
 103	unsigned long		ip;
 104};
 105
 106struct kretprobe_trace_entry_head {
 107	struct trace_entry	ent;
 108	unsigned long		func;
 109	unsigned long		ret_ip;
 110};
 111
 112/*
 113 * trace_flag_type is an enumeration that holds different
 114 * states when a trace occurs. These are:
 115 *  IRQS_OFF		- interrupts were disabled
 116 *  IRQS_NOSUPPORT	- arch does not support irqs_disabled_flags
 117 *  NEED_RESCHED	- reschedule is requested
 118 *  HARDIRQ		- inside an interrupt handler
 119 *  SOFTIRQ		- inside a softirq handler
 120 */
 121enum trace_flag_type {
 122	TRACE_FLAG_IRQS_OFF		= 0x01,
 123	TRACE_FLAG_IRQS_NOSUPPORT	= 0x02,
 124	TRACE_FLAG_NEED_RESCHED		= 0x04,
 125	TRACE_FLAG_HARDIRQ		= 0x08,
 126	TRACE_FLAG_SOFTIRQ		= 0x10,
 127	TRACE_FLAG_PREEMPT_RESCHED	= 0x20,
 128	TRACE_FLAG_NMI			= 0x40,
 129};
 130
 131#define TRACE_BUF_SIZE		1024
 132
 133struct trace_array;
 134
 135/*
 136 * The CPU trace array - it consists of thousands of trace entries
 137 * plus some other descriptor data: (for example which task started
 138 * the trace, etc.)
 139 */
 140struct trace_array_cpu {
 141	atomic_t		disabled;
 142	void			*buffer_page;	/* ring buffer spare */
 143
 144	unsigned long		entries;
 145	unsigned long		saved_latency;
 146	unsigned long		critical_start;
 147	unsigned long		critical_end;
 148	unsigned long		critical_sequence;
 149	unsigned long		nice;
 150	unsigned long		policy;
 151	unsigned long		rt_priority;
 152	unsigned long		skipped_entries;
 153	cycle_t			preempt_timestamp;
 154	pid_t			pid;
 155	kuid_t			uid;
 156	char			comm[TASK_COMM_LEN];
 157
 
 
 
 158	bool			ignore_pid;
 159};
 160
 161struct tracer;
 162struct trace_option_dentry;
 163
 164struct trace_buffer {
 165	struct trace_array		*tr;
 166	struct ring_buffer		*buffer;
 167	struct trace_array_cpu __percpu	*data;
 168	cycle_t				time_start;
 169	int				cpu;
 170};
 171
 172#define TRACE_FLAGS_MAX_SIZE		32
 173
 174struct trace_options {
 175	struct tracer			*tracer;
 176	struct trace_option_dentry	*topts;
 177};
 178
 179struct trace_pid_list {
 180	unsigned int			nr_pids;
 181	int				order;
 182	pid_t				*pids;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 183};
 184
 185/*
 186 * The trace array - an array of per-CPU trace arrays. This is the
 187 * highest level data structure that individual tracers deal with.
 188 * They have on/off state as well:
 189 */
 190struct trace_array {
 191	struct list_head	list;
 192	char			*name;
 193	struct trace_buffer	trace_buffer;
 194#ifdef CONFIG_TRACER_MAX_TRACE
 195	/*
 196	 * The max_buffer is used to snapshot the trace when a maximum
 197	 * latency is reached, or when the user initiates a snapshot.
 198	 * Some tracers will use this to store a maximum trace while
 199	 * it continues examining live traces.
 200	 *
 201	 * The buffers for the max_buffer are set up the same as the trace_buffer
 202	 * When a snapshot is taken, the buffer of the max_buffer is swapped
 203	 * with the buffer of the trace_buffer and the buffers are reset for
 204	 * the trace_buffer so the tracing can continue.
 205	 */
 206	struct trace_buffer	max_buffer;
 207	bool			allocated_snapshot;
 
 
 
 208	unsigned long		max_latency;
 
 
 
 
 
 209#endif
 210	struct trace_pid_list	__rcu *filtered_pids;
 
 211	/*
 212	 * max_lock is used to protect the swapping of buffers
 213	 * when taking a max snapshot. The buffers themselves are
 214	 * protected by per_cpu spinlocks. But the action of the swap
 215	 * needs its own lock.
 216	 *
 217	 * This is defined as a arch_spinlock_t in order to help
 218	 * with performance when lockdep debugging is enabled.
 219	 *
 220	 * It is also used in other places outside the update_max_tr
 221	 * so it needs to be defined outside of the
 222	 * CONFIG_TRACER_MAX_TRACE.
 223	 */
 224	arch_spinlock_t		max_lock;
 225	int			buffer_disabled;
 226#ifdef CONFIG_FTRACE_SYSCALLS
 227	int			sys_refcount_enter;
 228	int			sys_refcount_exit;
 229	struct trace_event_file __rcu *enter_syscall_files[NR_syscalls];
 230	struct trace_event_file __rcu *exit_syscall_files[NR_syscalls];
 231#endif
 232	int			stop_count;
 233	int			clock_id;
 234	int			nr_topts;
 
 
 
 235	struct tracer		*current_trace;
 236	unsigned int		trace_flags;
 237	unsigned char		trace_flags_index[TRACE_FLAGS_MAX_SIZE];
 238	unsigned int		flags;
 239	raw_spinlock_t		start_lock;
 
 240	struct dentry		*dir;
 241	struct dentry		*options;
 242	struct dentry		*percpu_dir;
 243	struct dentry		*event_dir;
 244	struct trace_options	*topts;
 245	struct list_head	systems;
 246	struct list_head	events;
 
 247	cpumask_var_t		tracing_cpumask; /* only trace on set CPUs */
 248	int			ref;
 
 249#ifdef CONFIG_FUNCTION_TRACER
 250	struct ftrace_ops	*ops;
 
 
 
 
 
 
 
 
 251	/* function tracing enabled */
 252	int			function_enabled;
 253#endif
 
 
 
 
 
 
 254};
 255
 256enum {
 257	TRACE_ARRAY_FL_GLOBAL	= (1 << 0)
 258};
 259
 260extern struct list_head ftrace_trace_arrays;
 261
 262extern struct mutex trace_types_lock;
 263
 264extern int trace_array_get(struct trace_array *tr);
 265extern void trace_array_put(struct trace_array *tr);
 
 
 
 
 
 
 
 
 266
 267/*
 268 * The global tracer (top) should be the first trace array added,
 269 * but we check the flag anyway.
 270 */
 271static inline struct trace_array *top_trace_array(void)
 272{
 273	struct trace_array *tr;
 274
 275	if (list_empty(&ftrace_trace_arrays))
 276		return NULL;
 277
 278	tr = list_entry(ftrace_trace_arrays.prev,
 279			typeof(*tr), list);
 280	WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL));
 281	return tr;
 282}
 283
 284#define FTRACE_CMP_TYPE(var, type) \
 285	__builtin_types_compatible_p(typeof(var), type *)
 286
 287#undef IF_ASSIGN
 288#define IF_ASSIGN(var, entry, etype, id)		\
 289	if (FTRACE_CMP_TYPE(var, etype)) {		\
 290		var = (typeof(var))(entry);		\
 291		WARN_ON(id && (entry)->type != id);	\
 292		break;					\
 293	}
 294
 295/* Will cause compile errors if type is not found. */
 296extern void __ftrace_bad_type(void);
 297
 298/*
 299 * The trace_assign_type is a verifier that the entry type is
 300 * the same as the type being assigned. To add new types simply
 301 * add a line with the following format:
 302 *
 303 * IF_ASSIGN(var, ent, type, id);
 304 *
 305 *  Where "type" is the trace type that includes the trace_entry
 306 *  as the "ent" item. And "id" is the trace identifier that is
 307 *  used in the trace_type enum.
 308 *
 309 *  If the type can have more than one id, then use zero.
 310 */
 311#define trace_assign_type(var, ent)					\
 312	do {								\
 313		IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN);	\
 314		IF_ASSIGN(var, ent, struct ctx_switch_entry, 0);	\
 315		IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK);	\
 316		IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
 317		IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT);	\
 318		IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT);	\
 319		IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS);	\
 
 
 
 
 320		IF_ASSIGN(var, ent, struct trace_mmiotrace_rw,		\
 321			  TRACE_MMIO_RW);				\
 322		IF_ASSIGN(var, ent, struct trace_mmiotrace_map,		\
 323			  TRACE_MMIO_MAP);				\
 324		IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
 325		IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry,	\
 326			  TRACE_GRAPH_ENT);		\
 327		IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry,	\
 328			  TRACE_GRAPH_RET);		\
 
 
 329		__ftrace_bad_type();					\
 330	} while (0)
 331
 332/*
 333 * An option specific to a tracer. This is a boolean value.
 334 * The bit is the bit index that sets its value on the
 335 * flags value in struct tracer_flags.
 336 */
 337struct tracer_opt {
 338	const char	*name; /* Will appear on the trace_options file */
 339	u32		bit; /* Mask assigned in val field in tracer_flags */
 340};
 341
 342/*
 343 * The set of specific options for a tracer. Your tracer
 344 * have to set the initial value of the flags val.
 345 */
 346struct tracer_flags {
 347	u32			val;
 348	struct tracer_opt	*opts;
 349	struct tracer		*trace;
 350};
 351
 352/* Makes more easy to define a tracer opt */
 353#define TRACER_OPT(s, b)	.name = #s, .bit = b
 354
 355
 356struct trace_option_dentry {
 357	struct tracer_opt		*opt;
 358	struct tracer_flags		*flags;
 359	struct trace_array		*tr;
 360	struct dentry			*entry;
 361};
 362
 363/**
 364 * struct tracer - a specific tracer and its callbacks to interact with tracefs
 365 * @name: the name chosen to select it on the available_tracers file
 366 * @init: called when one switches to this tracer (echo name > current_tracer)
 367 * @reset: called when one switches to another tracer
 368 * @start: called when tracing is unpaused (echo 1 > tracing_on)
 369 * @stop: called when tracing is paused (echo 0 > tracing_on)
 370 * @update_thresh: called when tracing_thresh is updated
 371 * @open: called when the trace file is opened
 372 * @pipe_open: called when the trace_pipe file is opened
 373 * @close: called when the trace file is released
 374 * @pipe_close: called when the trace_pipe file is released
 375 * @read: override the default read callback on trace_pipe
 376 * @splice_read: override the default splice_read callback on trace_pipe
 377 * @selftest: selftest to run on boot (see trace_selftest.c)
 378 * @print_headers: override the first lines that describe your columns
 379 * @print_line: callback that prints a trace
 380 * @set_flag: signals one of your private flags changed (trace_options file)
 381 * @flags: your private flags
 382 */
 383struct tracer {
 384	const char		*name;
 385	int			(*init)(struct trace_array *tr);
 386	void			(*reset)(struct trace_array *tr);
 387	void			(*start)(struct trace_array *tr);
 388	void			(*stop)(struct trace_array *tr);
 389	int			(*update_thresh)(struct trace_array *tr);
 390	void			(*open)(struct trace_iterator *iter);
 391	void			(*pipe_open)(struct trace_iterator *iter);
 392	void			(*close)(struct trace_iterator *iter);
 393	void			(*pipe_close)(struct trace_iterator *iter);
 394	ssize_t			(*read)(struct trace_iterator *iter,
 395					struct file *filp, char __user *ubuf,
 396					size_t cnt, loff_t *ppos);
 397	ssize_t			(*splice_read)(struct trace_iterator *iter,
 398					       struct file *filp,
 399					       loff_t *ppos,
 400					       struct pipe_inode_info *pipe,
 401					       size_t len,
 402					       unsigned int flags);
 403#ifdef CONFIG_FTRACE_STARTUP_TEST
 404	int			(*selftest)(struct tracer *trace,
 405					    struct trace_array *tr);
 406#endif
 407	void			(*print_header)(struct seq_file *m);
 408	enum print_line_t	(*print_line)(struct trace_iterator *iter);
 409	/* If you handled the flag setting, return 0 */
 410	int			(*set_flag)(struct trace_array *tr,
 411					    u32 old_flags, u32 bit, int set);
 412	/* Return 0 if OK with change, else return non-zero */
 413	int			(*flag_changed)(struct trace_array *tr,
 414						u32 mask, int set);
 415	struct tracer		*next;
 416	struct tracer_flags	*flags;
 417	int			enabled;
 418	int			ref;
 419	bool			print_max;
 420	bool			allow_instances;
 421#ifdef CONFIG_TRACER_MAX_TRACE
 422	bool			use_max_tr;
 423#endif
 
 
 424};
 425
 426
 427/* Only current can touch trace_recursion */
 428
 429/*
 430 * For function tracing recursion:
 431 *  The order of these bits are important.
 432 *
 433 *  When function tracing occurs, the following steps are made:
 434 *   If arch does not support a ftrace feature:
 435 *    call internal function (uses INTERNAL bits) which calls...
 436 *   If callback is registered to the "global" list, the list
 437 *    function is called and recursion checks the GLOBAL bits.
 438 *    then this function calls...
 439 *   The function callback, which can use the FTRACE bits to
 440 *    check for recursion.
 441 *
 442 * Now if the arch does not suppport a feature, and it calls
 443 * the global list function which calls the ftrace callback
 444 * all three of these steps will do a recursion protection.
 445 * There's no reason to do one if the previous caller already
 446 * did. The recursion that we are protecting against will
 447 * go through the same steps again.
 448 *
 449 * To prevent the multiple recursion checks, if a recursion
 450 * bit is set that is higher than the MAX bit of the current
 451 * check, then we know that the check was made by the previous
 452 * caller, and we can skip the current check.
 453 */
 454enum {
 455	TRACE_BUFFER_BIT,
 456	TRACE_BUFFER_NMI_BIT,
 457	TRACE_BUFFER_IRQ_BIT,
 458	TRACE_BUFFER_SIRQ_BIT,
 459
 460	/* Start of function recursion bits */
 461	TRACE_FTRACE_BIT,
 462	TRACE_FTRACE_NMI_BIT,
 463	TRACE_FTRACE_IRQ_BIT,
 464	TRACE_FTRACE_SIRQ_BIT,
 465
 466	/* INTERNAL_BITs must be greater than FTRACE_BITs */
 467	TRACE_INTERNAL_BIT,
 468	TRACE_INTERNAL_NMI_BIT,
 469	TRACE_INTERNAL_IRQ_BIT,
 470	TRACE_INTERNAL_SIRQ_BIT,
 471
 472	TRACE_BRANCH_BIT,
 473/*
 474 * Abuse of the trace_recursion.
 475 * As we need a way to maintain state if we are tracing the function
 476 * graph in irq because we want to trace a particular function that
 477 * was called in irq context but we have irq tracing off. Since this
 478 * can only be modified by current, we can reuse trace_recursion.
 479 */
 480	TRACE_IRQ_BIT,
 481};
 482
 483#define trace_recursion_set(bit)	do { (current)->trace_recursion |= (1<<(bit)); } while (0)
 484#define trace_recursion_clear(bit)	do { (current)->trace_recursion &= ~(1<<(bit)); } while (0)
 485#define trace_recursion_test(bit)	((current)->trace_recursion & (1<<(bit)))
 486
 487#define TRACE_CONTEXT_BITS	4
 488
 489#define TRACE_FTRACE_START	TRACE_FTRACE_BIT
 490#define TRACE_FTRACE_MAX	((1 << (TRACE_FTRACE_START + TRACE_CONTEXT_BITS)) - 1)
 491
 492#define TRACE_LIST_START	TRACE_INTERNAL_BIT
 493#define TRACE_LIST_MAX		((1 << (TRACE_LIST_START + TRACE_CONTEXT_BITS)) - 1)
 494
 495#define TRACE_CONTEXT_MASK	TRACE_LIST_MAX
 496
 497static __always_inline int trace_get_context_bit(void)
 498{
 499	int bit;
 500
 501	if (in_interrupt()) {
 502		if (in_nmi())
 503			bit = 0;
 504
 505		else if (in_irq())
 506			bit = 1;
 507		else
 508			bit = 2;
 509	} else
 510		bit = 3;
 511
 512	return bit;
 513}
 514
 515static __always_inline int trace_test_and_set_recursion(int start, int max)
 516{
 517	unsigned int val = current->trace_recursion;
 518	int bit;
 519
 520	/* A previous recursion check was made */
 521	if ((val & TRACE_CONTEXT_MASK) > max)
 522		return 0;
 523
 524	bit = trace_get_context_bit() + start;
 525	if (unlikely(val & (1 << bit)))
 526		return -1;
 527
 528	val |= 1 << bit;
 529	current->trace_recursion = val;
 530	barrier();
 531
 532	return bit;
 533}
 534
 535static __always_inline void trace_clear_recursion(int bit)
 536{
 537	unsigned int val = current->trace_recursion;
 538
 539	if (!bit)
 540		return;
 541
 542	bit = 1 << bit;
 543	val &= ~bit;
 544
 545	barrier();
 546	current->trace_recursion = val;
 547}
 548
 549static inline struct ring_buffer_iter *
 550trace_buffer_iter(struct trace_iterator *iter, int cpu)
 551{
 552	if (iter->buffer_iter && iter->buffer_iter[cpu])
 553		return iter->buffer_iter[cpu];
 554	return NULL;
 555}
 556
 557int tracer_init(struct tracer *t, struct trace_array *tr);
 558int tracing_is_enabled(void);
 559void tracing_reset(struct trace_buffer *buf, int cpu);
 560void tracing_reset_online_cpus(struct trace_buffer *buf);
 561void tracing_reset_current(int cpu);
 562void tracing_reset_all_online_cpus(void);
 563int tracing_open_generic(struct inode *inode, struct file *filp);
 
 564bool tracing_is_disabled(void);
 
 
 
 565struct dentry *trace_create_file(const char *name,
 566				 umode_t mode,
 567				 struct dentry *parent,
 568				 void *data,
 569				 const struct file_operations *fops);
 570
 571struct dentry *tracing_init_dentry(void);
 572
 573struct ring_buffer_event;
 574
 575struct ring_buffer_event *
 576trace_buffer_lock_reserve(struct ring_buffer *buffer,
 577			  int type,
 578			  unsigned long len,
 579			  unsigned long flags,
 580			  int pc);
 581
 582struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
 583						struct trace_array_cpu *data);
 584
 585struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
 586					  int *ent_cpu, u64 *ent_ts);
 587
 588void __buffer_unlock_commit(struct ring_buffer *buffer,
 589			    struct ring_buffer_event *event);
 
 
 
 
 
 590
 591int trace_empty(struct trace_iterator *iter);
 592
 593void *trace_find_next_entry_inc(struct trace_iterator *iter);
 594
 595void trace_init_global_iter(struct trace_iterator *iter);
 596
 597void tracing_iter_reset(struct trace_iterator *iter, int cpu);
 598
 
 
 
 599void trace_function(struct trace_array *tr,
 600		    unsigned long ip,
 601		    unsigned long parent_ip,
 602		    unsigned long flags, int pc);
 603void trace_graph_function(struct trace_array *tr,
 604		    unsigned long ip,
 605		    unsigned long parent_ip,
 606		    unsigned long flags, int pc);
 607void trace_latency_header(struct seq_file *m);
 608void trace_default_header(struct seq_file *m);
 609void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
 610int trace_empty(struct trace_iterator *iter);
 611
 612void trace_graph_return(struct ftrace_graph_ret *trace);
 613int trace_graph_entry(struct ftrace_graph_ent *trace);
 614void set_graph_array(struct trace_array *tr);
 615
 616void tracing_start_cmdline_record(void);
 617void tracing_stop_cmdline_record(void);
 
 
 
 618int register_tracer(struct tracer *type);
 619int is_tracing_stopped(void);
 620
 621loff_t tracing_lseek(struct file *file, loff_t offset, int whence);
 622
 623extern cpumask_var_t __read_mostly tracing_buffer_mask;
 624
 625#define for_each_tracing_cpu(cpu)	\
 626	for_each_cpu(cpu, tracing_buffer_mask)
 627
 628extern unsigned long nsecs_to_usecs(unsigned long nsecs);
 629
 630extern unsigned long tracing_thresh;
 631
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 632#ifdef CONFIG_TRACER_MAX_TRACE
 633void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu);
 
 634void update_max_tr_single(struct trace_array *tr,
 635			  struct task_struct *tsk, int cpu);
 636#endif /* CONFIG_TRACER_MAX_TRACE */
 637
 638#ifdef CONFIG_STACKTRACE
 639void ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags,
 640			    int pc);
 
 641
 642void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
 643		   int pc);
 644#else
 645static inline void ftrace_trace_userstack(struct ring_buffer *buffer,
 646					  unsigned long flags, int pc)
 647{
 648}
 649
 650static inline void __trace_stack(struct trace_array *tr, unsigned long flags,
 651				 int skip, int pc)
 
 
 
 652{
 653}
 654#endif /* CONFIG_STACKTRACE */
 655
 656extern cycle_t ftrace_now(int cpu);
 
 
 
 
 657
 658extern void trace_find_cmdline(int pid, char comm[]);
 
 
 659
 660#ifdef CONFIG_DYNAMIC_FTRACE
 661extern unsigned long ftrace_update_tot_cnt;
 
 
 
 
 
 662#endif
 663#define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
 664extern int DYN_FTRACE_TEST_NAME(void);
 665#define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
 666extern int DYN_FTRACE_TEST_NAME2(void);
 667
 668extern bool ring_buffer_expanded;
 669extern bool tracing_selftest_disabled;
 670
 671#ifdef CONFIG_FTRACE_STARTUP_TEST
 
 
 672extern int trace_selftest_startup_function(struct tracer *trace,
 673					   struct trace_array *tr);
 674extern int trace_selftest_startup_function_graph(struct tracer *trace,
 675						 struct trace_array *tr);
 676extern int trace_selftest_startup_irqsoff(struct tracer *trace,
 677					  struct trace_array *tr);
 678extern int trace_selftest_startup_preemptoff(struct tracer *trace,
 679					     struct trace_array *tr);
 680extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
 681						 struct trace_array *tr);
 682extern int trace_selftest_startup_wakeup(struct tracer *trace,
 683					 struct trace_array *tr);
 684extern int trace_selftest_startup_nop(struct tracer *trace,
 685					 struct trace_array *tr);
 686extern int trace_selftest_startup_sched_switch(struct tracer *trace,
 687					       struct trace_array *tr);
 688extern int trace_selftest_startup_branch(struct tracer *trace,
 689					 struct trace_array *tr);
 690/*
 691 * Tracer data references selftest functions that only occur
 692 * on boot up. These can be __init functions. Thus, when selftests
 693 * are enabled, then the tracers need to reference __init functions.
 694 */
 695#define __tracer_data		__refdata
 696#else
 
 
 
 697/* Tracers are seldom changed. Optimize when selftests are disabled. */
 698#define __tracer_data		__read_mostly
 699#endif /* CONFIG_FTRACE_STARTUP_TEST */
 700
 701extern void *head_page(struct trace_array_cpu *data);
 702extern unsigned long long ns2usecs(cycle_t nsec);
 703extern int
 704trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
 705extern int
 706trace_vprintk(unsigned long ip, const char *fmt, va_list args);
 707extern int
 708trace_array_vprintk(struct trace_array *tr,
 709		    unsigned long ip, const char *fmt, va_list args);
 710int trace_array_printk(struct trace_array *tr,
 711		       unsigned long ip, const char *fmt, ...);
 712int trace_array_printk_buf(struct ring_buffer *buffer,
 713			   unsigned long ip, const char *fmt, ...);
 714void trace_printk_seq(struct trace_seq *s);
 715enum print_line_t print_trace_line(struct trace_iterator *iter);
 716
 717extern char trace_find_mark(unsigned long long duration);
 718
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 719/* Standard output formatting function used for function return traces */
 720#ifdef CONFIG_FUNCTION_GRAPH_TRACER
 721
 722/* Flag options */
 723#define TRACE_GRAPH_PRINT_OVERRUN       0x1
 724#define TRACE_GRAPH_PRINT_CPU           0x2
 725#define TRACE_GRAPH_PRINT_OVERHEAD      0x4
 726#define TRACE_GRAPH_PRINT_PROC          0x8
 727#define TRACE_GRAPH_PRINT_DURATION      0x10
 728#define TRACE_GRAPH_PRINT_ABS_TIME      0x20
 729#define TRACE_GRAPH_PRINT_IRQS          0x40
 730#define TRACE_GRAPH_PRINT_TAIL          0x80
 731#define TRACE_GRAPH_SLEEP_TIME		0x100
 732#define TRACE_GRAPH_GRAPH_TIME		0x200
 
 733#define TRACE_GRAPH_PRINT_FILL_SHIFT	28
 734#define TRACE_GRAPH_PRINT_FILL_MASK	(0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT)
 735
 736extern void ftrace_graph_sleep_time_control(bool enable);
 
 
 737extern void ftrace_graph_graph_time_control(bool enable);
 
 
 
 738
 739extern enum print_line_t
 740print_graph_function_flags(struct trace_iterator *iter, u32 flags);
 741extern void print_graph_headers_flags(struct seq_file *s, u32 flags);
 742extern void
 743trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
 744extern void graph_trace_open(struct trace_iterator *iter);
 745extern void graph_trace_close(struct trace_iterator *iter);
 746extern int __trace_graph_entry(struct trace_array *tr,
 747			       struct ftrace_graph_ent *trace,
 748			       unsigned long flags, int pc);
 749extern void __trace_graph_return(struct trace_array *tr,
 750				 struct ftrace_graph_ret *trace,
 751				 unsigned long flags, int pc);
 752
 753
 754#ifdef CONFIG_DYNAMIC_FTRACE
 755/* TODO: make this variable */
 756#define FTRACE_GRAPH_MAX_FUNCS		32
 757extern int ftrace_graph_count;
 758extern unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS];
 759extern int ftrace_graph_notrace_count;
 760extern unsigned long ftrace_graph_notrace_funcs[FTRACE_GRAPH_MAX_FUNCS];
 761
 762static inline int ftrace_graph_addr(unsigned long addr)
 763{
 764	int i;
 765
 766	if (!ftrace_graph_count)
 767		return 1;
 768
 769	for (i = 0; i < ftrace_graph_count; i++) {
 770		if (addr == ftrace_graph_funcs[i]) {
 771			/*
 772			 * If no irqs are to be traced, but a set_graph_function
 773			 * is set, and called by an interrupt handler, we still
 774			 * want to trace it.
 775			 */
 776			if (in_irq())
 777				trace_recursion_set(TRACE_IRQ_BIT);
 778			else
 779				trace_recursion_clear(TRACE_IRQ_BIT);
 780			return 1;
 781		}
 782	}
 783
 784	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 785}
 786
 787static inline int ftrace_graph_notrace_addr(unsigned long addr)
 788{
 789	int i;
 
 790
 791	if (!ftrace_graph_notrace_count)
 792		return 0;
 793
 794	for (i = 0; i < ftrace_graph_notrace_count; i++) {
 795		if (addr == ftrace_graph_notrace_funcs[i])
 796			return 1;
 797	}
 
 
 
 
 798
 799	return 0;
 
 
 
 
 800}
 801#else
 802static inline int ftrace_graph_addr(unsigned long addr)
 803{
 804	return 1;
 805}
 806
 807static inline int ftrace_graph_notrace_addr(unsigned long addr)
 808{
 809	return 0;
 810}
 
 
 811#endif /* CONFIG_DYNAMIC_FTRACE */
 
 
 
 
 
 
 
 
 
 
 
 
 812#else /* CONFIG_FUNCTION_GRAPH_TRACER */
 813static inline enum print_line_t
 814print_graph_function_flags(struct trace_iterator *iter, u32 flags)
 815{
 816	return TRACE_TYPE_UNHANDLED;
 817}
 818#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
 819
 820extern struct list_head ftrace_pids;
 821
 822#ifdef CONFIG_FUNCTION_TRACER
 
 
 
 
 
 
 
 
 
 
 
 
 823extern bool ftrace_filter_param __initdata;
 824static inline int ftrace_trace_task(struct task_struct *task)
 825{
 826	if (list_empty(&ftrace_pids))
 827		return 1;
 828
 829	return test_tsk_trace_trace(task);
 830}
 831extern int ftrace_is_dead(void);
 832int ftrace_create_function_files(struct trace_array *tr,
 833				 struct dentry *parent);
 834void ftrace_destroy_function_files(struct trace_array *tr);
 
 
 835void ftrace_init_global_array_ops(struct trace_array *tr);
 836void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func);
 837void ftrace_reset_array_ops(struct trace_array *tr);
 838int using_ftrace_ops_list_func(void);
 
 
 
 
 
 839#else
 840static inline int ftrace_trace_task(struct task_struct *task)
 841{
 842	return 1;
 843}
 844static inline int ftrace_is_dead(void) { return 0; }
 845static inline int
 846ftrace_create_function_files(struct trace_array *tr,
 847			     struct dentry *parent)
 848{
 849	return 0;
 850}
 
 
 
 
 
 851static inline void ftrace_destroy_function_files(struct trace_array *tr) { }
 852static inline __init void
 853ftrace_init_global_array_ops(struct trace_array *tr) { }
 854static inline void ftrace_reset_array_ops(struct trace_array *tr) { }
 
 
 
 
 
 855/* ftace_func_t type is not defined, use macro instead of static inline */
 856#define ftrace_init_array_ops(tr, func) do { } while (0)
 857#endif /* CONFIG_FUNCTION_TRACER */
 858
 859#if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 860void ftrace_create_filter_files(struct ftrace_ops *ops,
 861				struct dentry *parent);
 862void ftrace_destroy_filter_files(struct ftrace_ops *ops);
 
 
 
 
 
 863#else
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 864/*
 865 * The ops parameter passed in is usually undefined.
 866 * This must be a macro.
 867 */
 868#define ftrace_create_filter_files(ops, parent) do { } while (0)
 869#define ftrace_destroy_filter_files(ops) do { } while (0)
 870#endif /* CONFIG_FUNCTION_TRACER && CONFIG_DYNAMIC_FTRACE */
 871
 872bool ftrace_event_is_function(struct trace_event_call *call);
 873
 874/*
 875 * struct trace_parser - servers for reading the user input separated by spaces
 876 * @cont: set if the input is not complete - no final space char was found
 877 * @buffer: holds the parsed user input
 878 * @idx: user input length
 879 * @size: buffer size
 880 */
 881struct trace_parser {
 882	bool		cont;
 883	char		*buffer;
 884	unsigned	idx;
 885	unsigned	size;
 886};
 887
 888static inline bool trace_parser_loaded(struct trace_parser *parser)
 889{
 890	return (parser->idx != 0);
 891}
 892
 893static inline bool trace_parser_cont(struct trace_parser *parser)
 894{
 895	return parser->cont;
 896}
 897
 898static inline void trace_parser_clear(struct trace_parser *parser)
 899{
 900	parser->cont = false;
 901	parser->idx = 0;
 902}
 903
 904extern int trace_parser_get_init(struct trace_parser *parser, int size);
 905extern void trace_parser_put(struct trace_parser *parser);
 906extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
 907	size_t cnt, loff_t *ppos);
 908
 909/*
 910 * Only create function graph options if function graph is configured.
 911 */
 912#ifdef CONFIG_FUNCTION_GRAPH_TRACER
 913# define FGRAPH_FLAGS						\
 914		C(DISPLAY_GRAPH,	"display-graph"),
 915#else
 916# define FGRAPH_FLAGS
 917#endif
 918
 919#ifdef CONFIG_BRANCH_TRACER
 920# define BRANCH_FLAGS					\
 921		C(BRANCH,		"branch"),
 922#else
 923# define BRANCH_FLAGS
 924#endif
 925
 926#ifdef CONFIG_FUNCTION_TRACER
 927# define FUNCTION_FLAGS						\
 928		C(FUNCTION,		"function-trace"),
 
 929# define FUNCTION_DEFAULT_FLAGS		TRACE_ITER_FUNCTION
 930#else
 931# define FUNCTION_FLAGS
 932# define FUNCTION_DEFAULT_FLAGS		0UL
 
 933#endif
 934
 935#ifdef CONFIG_STACKTRACE
 936# define STACK_FLAGS				\
 937		C(STACKTRACE,		"stacktrace"),
 938#else
 939# define STACK_FLAGS
 940#endif
 941
 942/*
 943 * trace_iterator_flags is an enumeration that defines bit
 944 * positions into trace_flags that controls the output.
 945 *
 946 * NOTE: These bits must match the trace_options array in
 947 *       trace.c (this macro guarantees it).
 948 */
 949#define TRACE_FLAGS						\
 950		C(PRINT_PARENT,		"print-parent"),	\
 951		C(SYM_OFFSET,		"sym-offset"),		\
 952		C(SYM_ADDR,		"sym-addr"),		\
 953		C(VERBOSE,		"verbose"),		\
 954		C(RAW,			"raw"),			\
 955		C(HEX,			"hex"),			\
 956		C(BIN,			"bin"),			\
 957		C(BLOCK,		"block"),		\
 958		C(PRINTK,		"trace_printk"),	\
 959		C(ANNOTATE,		"annotate"),		\
 960		C(USERSTACKTRACE,	"userstacktrace"),	\
 961		C(SYM_USEROBJ,		"sym-userobj"),		\
 962		C(PRINTK_MSGONLY,	"printk-msg-only"),	\
 963		C(CONTEXT_INFO,		"context-info"),   /* Print pid/cpu/time */ \
 964		C(LATENCY_FMT,		"latency-format"),	\
 965		C(RECORD_CMD,		"record-cmd"),		\
 
 966		C(OVERWRITE,		"overwrite"),		\
 967		C(STOP_ON_FREE,		"disable_on_free"),	\
 968		C(IRQ_INFO,		"irq-info"),		\
 969		C(MARKERS,		"markers"),		\
 
 
 
 970		FUNCTION_FLAGS					\
 971		FGRAPH_FLAGS					\
 972		STACK_FLAGS					\
 973		BRANCH_FLAGS
 974
 975/*
 976 * By defining C, we can make TRACE_FLAGS a list of bit names
 977 * that will define the bits for the flag masks.
 978 */
 979#undef C
 980#define C(a, b) TRACE_ITER_##a##_BIT
 981
 982enum trace_iterator_bits {
 983	TRACE_FLAGS
 984	/* Make sure we don't go more than we have bits for */
 985	TRACE_ITER_LAST_BIT
 986};
 987
 988/*
 989 * By redefining C, we can make TRACE_FLAGS a list of masks that
 990 * use the bits as defined above.
 991 */
 992#undef C
 993#define C(a, b) TRACE_ITER_##a = (1 << TRACE_ITER_##a##_BIT)
 994
 995enum trace_iterator_flags { TRACE_FLAGS };
 996
 997/*
 998 * TRACE_ITER_SYM_MASK masks the options in trace_flags that
 999 * control the output of kernel symbols.
1000 */
1001#define TRACE_ITER_SYM_MASK \
1002	(TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
1003
1004extern struct tracer nop_trace;
1005
1006#ifdef CONFIG_BRANCH_TRACER
1007extern int enable_branch_tracing(struct trace_array *tr);
1008extern void disable_branch_tracing(void);
1009static inline int trace_branch_enable(struct trace_array *tr)
1010{
1011	if (tr->trace_flags & TRACE_ITER_BRANCH)
1012		return enable_branch_tracing(tr);
1013	return 0;
1014}
1015static inline void trace_branch_disable(void)
1016{
1017	/* due to races, always disable */
1018	disable_branch_tracing();
1019}
1020#else
1021static inline int trace_branch_enable(struct trace_array *tr)
1022{
1023	return 0;
1024}
1025static inline void trace_branch_disable(void)
1026{
1027}
1028#endif /* CONFIG_BRANCH_TRACER */
1029
1030/* set ring buffers to default size if not already done so */
1031int tracing_update_buffers(void);
1032
1033struct ftrace_event_field {
1034	struct list_head	link;
1035	const char		*name;
1036	const char		*type;
1037	int			filter_type;
1038	int			offset;
1039	int			size;
1040	int			is_signed;
1041};
1042
 
 
1043struct event_filter {
1044	int			n_preds;	/* Number assigned */
1045	int			a_preds;	/* allocated */
1046	struct filter_pred	*preds;
1047	struct filter_pred	*root;
1048	char			*filter_string;
1049};
1050
1051struct event_subsystem {
1052	struct list_head	list;
1053	const char		*name;
1054	struct event_filter	*filter;
1055	int			ref_count;
1056};
1057
1058struct trace_subsystem_dir {
1059	struct list_head		list;
1060	struct event_subsystem		*subsystem;
1061	struct trace_array		*tr;
1062	struct dentry			*entry;
1063	int				ref_count;
1064	int				nr_events;
1065};
1066
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1067#define FILTER_PRED_INVALID	((unsigned short)-1)
1068#define FILTER_PRED_IS_RIGHT	(1 << 15)
1069#define FILTER_PRED_FOLD	(1 << 15)
1070
1071/*
1072 * The max preds is the size of unsigned short with
1073 * two flags at the MSBs. One bit is used for both the IS_RIGHT
1074 * and FOLD flags. The other is reserved.
1075 *
1076 * 2^14 preds is way more than enough.
1077 */
1078#define MAX_FILTER_PRED		16384
1079
1080struct filter_pred;
1081struct regex;
1082
1083typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event);
1084
1085typedef int (*regex_match_func)(char *str, struct regex *r, int len);
1086
1087enum regex_type {
1088	MATCH_FULL = 0,
1089	MATCH_FRONT_ONLY,
1090	MATCH_MIDDLE_ONLY,
1091	MATCH_END_ONLY,
 
 
1092};
1093
1094struct regex {
1095	char			pattern[MAX_FILTER_STR_VAL];
1096	int			len;
1097	int			field_len;
1098	regex_match_func	match;
1099};
1100
1101struct filter_pred {
1102	filter_pred_fn_t 	fn;
1103	u64 			val;
1104	struct regex		regex;
1105	unsigned short		*ops;
1106	struct ftrace_event_field *field;
1107	int 			offset;
1108	int 			not;
1109	int 			op;
1110	unsigned short		index;
1111	unsigned short		parent;
1112	unsigned short		left;
1113	unsigned short		right;
1114};
1115
1116static inline bool is_string_field(struct ftrace_event_field *field)
1117{
1118	return field->filter_type == FILTER_DYN_STRING ||
1119	       field->filter_type == FILTER_STATIC_STRING ||
1120	       field->filter_type == FILTER_PTR_STRING;
 
1121}
1122
1123static inline bool is_function_field(struct ftrace_event_field *field)
1124{
1125	return field->filter_type == FILTER_TRACE_FN;
1126}
1127
1128extern enum regex_type
1129filter_parse_regex(char *buff, int len, char **search, int *not);
1130extern void print_event_filter(struct trace_event_file *file,
1131			       struct trace_seq *s);
1132extern int apply_event_filter(struct trace_event_file *file,
1133			      char *filter_string);
1134extern int apply_subsystem_event_filter(struct trace_subsystem_dir *dir,
1135					char *filter_string);
1136extern void print_subsystem_event_filter(struct event_subsystem *system,
1137					 struct trace_seq *s);
1138extern int filter_assign_type(const char *type);
1139extern int create_event_filter(struct trace_event_call *call,
 
1140			       char *filter_str, bool set_str,
1141			       struct event_filter **filterp);
1142extern void free_event_filter(struct event_filter *filter);
1143
1144struct ftrace_event_field *
1145trace_find_event_field(struct trace_event_call *call, char *name);
1146
1147extern void trace_event_enable_cmd_record(bool enable);
 
 
 
1148extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr);
1149extern int event_trace_del_tracer(struct trace_array *tr);
 
1150
 
 
 
1151extern struct trace_event_file *find_event_file(struct trace_array *tr,
1152						const char *system,
1153						const char *event);
1154
1155static inline void *event_file_data(struct file *filp)
1156{
1157	return ACCESS_ONCE(file_inode(filp)->i_private);
1158}
1159
1160extern struct mutex event_mutex;
1161extern struct list_head ftrace_events;
1162
1163extern const struct file_operations event_trigger_fops;
 
 
 
 
 
 
 
 
 
 
 
1164
1165extern int register_trigger_cmds(void);
1166extern void clear_event_triggers(struct trace_array *tr);
1167
1168struct event_trigger_data {
1169	unsigned long			count;
1170	int				ref;
1171	struct event_trigger_ops	*ops;
1172	struct event_command		*cmd_ops;
1173	struct event_filter __rcu	*filter;
1174	char				*filter_str;
1175	void				*private_data;
1176	bool				paused;
 
1177	struct list_head		list;
1178};
1179
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1180extern void trigger_data_free(struct event_trigger_data *data);
1181extern int event_trigger_init(struct event_trigger_ops *ops,
1182			      struct event_trigger_data *data);
1183extern int trace_event_trigger_enable_disable(struct trace_event_file *file,
1184					      int trigger_enable);
1185extern void update_cond_flag(struct trace_event_file *file);
1186extern void unregister_trigger(char *glob, struct event_trigger_ops *ops,
1187			       struct event_trigger_data *test,
1188			       struct trace_event_file *file);
1189extern int set_trigger_filter(char *filter_str,
1190			      struct event_trigger_data *trigger_data,
1191			      struct trace_event_file *file);
 
 
 
 
 
 
 
 
 
 
 
1192extern int register_event_command(struct event_command *cmd);
 
 
1193
1194/**
1195 * struct event_trigger_ops - callbacks for trace event triggers
1196 *
1197 * The methods in this structure provide per-event trigger hooks for
1198 * various trigger operations.
1199 *
1200 * All the methods below, except for @init() and @free(), must be
1201 * implemented.
1202 *
1203 * @func: The trigger 'probe' function called when the triggering
1204 *	event occurs.  The data passed into this callback is the data
1205 *	that was supplied to the event_command @reg() function that
1206 *	registered the trigger (see struct event_command) along with
1207 *	the trace record, rec.
1208 *
1209 * @init: An optional initialization function called for the trigger
1210 *	when the trigger is registered (via the event_command reg()
1211 *	function).  This can be used to perform per-trigger
1212 *	initialization such as incrementing a per-trigger reference
1213 *	count, for instance.  This is usually implemented by the
1214 *	generic utility function @event_trigger_init() (see
1215 *	trace_event_triggers.c).
1216 *
1217 * @free: An optional de-initialization function called for the
1218 *	trigger when the trigger is unregistered (via the
1219 *	event_command @reg() function).  This can be used to perform
1220 *	per-trigger de-initialization such as decrementing a
1221 *	per-trigger reference count and freeing corresponding trigger
1222 *	data, for instance.  This is usually implemented by the
1223 *	generic utility function @event_trigger_free() (see
1224 *	trace_event_triggers.c).
1225 *
1226 * @print: The callback function invoked to have the trigger print
1227 *	itself.  This is usually implemented by a wrapper function
1228 *	that calls the generic utility function @event_trigger_print()
1229 *	(see trace_event_triggers.c).
1230 */
1231struct event_trigger_ops {
1232	void			(*func)(struct event_trigger_data *data,
1233					void *rec);
 
1234	int			(*init)(struct event_trigger_ops *ops,
1235					struct event_trigger_data *data);
1236	void			(*free)(struct event_trigger_ops *ops,
1237					struct event_trigger_data *data);
1238	int			(*print)(struct seq_file *m,
1239					 struct event_trigger_ops *ops,
1240					 struct event_trigger_data *data);
1241};
1242
1243/**
1244 * struct event_command - callbacks and data members for event commands
1245 *
1246 * Event commands are invoked by users by writing the command name
1247 * into the 'trigger' file associated with a trace event.  The
1248 * parameters associated with a specific invocation of an event
1249 * command are used to create an event trigger instance, which is
1250 * added to the list of trigger instances associated with that trace
1251 * event.  When the event is hit, the set of triggers associated with
1252 * that event is invoked.
1253 *
1254 * The data members in this structure provide per-event command data
1255 * for various event commands.
1256 *
1257 * All the data members below, except for @post_trigger, must be set
1258 * for each event command.
1259 *
1260 * @name: The unique name that identifies the event command.  This is
1261 *	the name used when setting triggers via trigger files.
1262 *
1263 * @trigger_type: A unique id that identifies the event command
1264 *	'type'.  This value has two purposes, the first to ensure that
1265 *	only one trigger of the same type can be set at a given time
1266 *	for a particular event e.g. it doesn't make sense to have both
1267 *	a traceon and traceoff trigger attached to a single event at
1268 *	the same time, so traceon and traceoff have the same type
1269 *	though they have different names.  The @trigger_type value is
1270 *	also used as a bit value for deferring the actual trigger
1271 *	action until after the current event is finished.  Some
1272 *	commands need to do this if they themselves log to the trace
1273 *	buffer (see the @post_trigger() member below).  @trigger_type
1274 *	values are defined by adding new values to the trigger_type
1275 *	enum in include/linux/trace_events.h.
1276 *
1277 * @flags: See the enum event_command_flags below.
1278 *
1279 * All the methods below, except for @set_filter() and @unreg_all(),
1280 * must be implemented.
1281 *
1282 * @func: The callback function responsible for parsing and
1283 *	registering the trigger written to the 'trigger' file by the
1284 *	user.  It allocates the trigger instance and registers it with
1285 *	the appropriate trace event.  It makes use of the other
1286 *	event_command callback functions to orchestrate this, and is
1287 *	usually implemented by the generic utility function
1288 *	@event_trigger_callback() (see trace_event_triggers.c).
1289 *
1290 * @reg: Adds the trigger to the list of triggers associated with the
1291 *	event, and enables the event trigger itself, after
1292 *	initializing it (via the event_trigger_ops @init() function).
1293 *	This is also where commands can use the @trigger_type value to
1294 *	make the decision as to whether or not multiple instances of
1295 *	the trigger should be allowed.  This is usually implemented by
1296 *	the generic utility function @register_trigger() (see
1297 *	trace_event_triggers.c).
1298 *
1299 * @unreg: Removes the trigger from the list of triggers associated
1300 *	with the event, and disables the event trigger itself, after
1301 *	initializing it (via the event_trigger_ops @free() function).
1302 *	This is usually implemented by the generic utility function
1303 *	@unregister_trigger() (see trace_event_triggers.c).
1304 *
1305 * @unreg_all: An optional function called to remove all the triggers
1306 *	from the list of triggers associated with the event.  Called
1307 *	when a trigger file is opened in truncate mode.
1308 *
1309 * @set_filter: An optional function called to parse and set a filter
1310 *	for the trigger.  If no @set_filter() method is set for the
1311 *	event command, filters set by the user for the command will be
1312 *	ignored.  This is usually implemented by the generic utility
1313 *	function @set_trigger_filter() (see trace_event_triggers.c).
1314 *
1315 * @get_trigger_ops: The callback function invoked to retrieve the
1316 *	event_trigger_ops implementation associated with the command.
1317 */
1318struct event_command {
1319	struct list_head	list;
1320	char			*name;
1321	enum event_trigger_type	trigger_type;
1322	int			flags;
1323	int			(*func)(struct event_command *cmd_ops,
1324					struct trace_event_file *file,
1325					char *glob, char *cmd, char *params);
1326	int			(*reg)(char *glob,
1327				       struct event_trigger_ops *ops,
1328				       struct event_trigger_data *data,
1329				       struct trace_event_file *file);
1330	void			(*unreg)(char *glob,
1331					 struct event_trigger_ops *ops,
1332					 struct event_trigger_data *data,
1333					 struct trace_event_file *file);
1334	void			(*unreg_all)(struct trace_event_file *file);
1335	int			(*set_filter)(char *filter_str,
1336					      struct event_trigger_data *data,
1337					      struct trace_event_file *file);
1338	struct event_trigger_ops *(*get_trigger_ops)(char *cmd, char *param);
1339};
1340
1341/**
1342 * enum event_command_flags - flags for struct event_command
1343 *
1344 * @POST_TRIGGER: A flag that says whether or not this command needs
1345 *	to have its action delayed until after the current event has
1346 *	been closed.  Some triggers need to avoid being invoked while
1347 *	an event is currently in the process of being logged, since
1348 *	the trigger may itself log data into the trace buffer.  Thus
1349 *	we make sure the current event is committed before invoking
1350 *	those triggers.  To do that, the trigger invocation is split
1351 *	in two - the first part checks the filter using the current
1352 *	trace record; if a command has the @post_trigger flag set, it
1353 *	sets a bit for itself in the return value, otherwise it
1354 *	directly invokes the trigger.  Once all commands have been
1355 *	either invoked or set their return flag, the current record is
1356 *	either committed or discarded.  At that point, if any commands
1357 *	have deferred their triggers, those commands are finally
1358 *	invoked following the close of the current event.  In other
1359 *	words, if the event_trigger_ops @func() probe implementation
1360 *	itself logs to the trace buffer, this flag should be set,
1361 *	otherwise it can be left unspecified.
1362 *
1363 * @NEEDS_REC: A flag that says whether or not this command needs
1364 *	access to the trace record in order to perform its function,
1365 *	regardless of whether or not it has a filter associated with
1366 *	it (filters make a trigger require access to the trace record
1367 *	but are not always present).
1368 */
1369enum event_command_flags {
1370	EVENT_CMD_FL_POST_TRIGGER	= 1,
1371	EVENT_CMD_FL_NEEDS_REC		= 2,
1372};
1373
1374static inline bool event_command_post_trigger(struct event_command *cmd_ops)
1375{
1376	return cmd_ops->flags & EVENT_CMD_FL_POST_TRIGGER;
1377}
1378
1379static inline bool event_command_needs_rec(struct event_command *cmd_ops)
1380{
1381	return cmd_ops->flags & EVENT_CMD_FL_NEEDS_REC;
1382}
1383
1384extern int trace_event_enable_disable(struct trace_event_file *file,
1385				      int enable, int soft_disable);
1386extern int tracing_alloc_snapshot(void);
 
 
 
 
 
1387
1388extern const char *__start___trace_bprintk_fmt[];
1389extern const char *__stop___trace_bprintk_fmt[];
1390
1391extern const char *__start___tracepoint_str[];
1392extern const char *__stop___tracepoint_str[];
1393
1394void trace_printk_control(bool enabled);
1395void trace_printk_init_buffers(void);
1396void trace_printk_start_comm(void);
1397int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set);
1398int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled);
1399
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1400/*
1401 * Normal trace_printk() and friends allocates special buffers
1402 * to do the manipulation, as well as saves the print formats
1403 * into sections to display. But the trace infrastructure wants
1404 * to use these without the added overhead at the price of being
1405 * a bit slower (used mainly for warnings, where we don't care
1406 * about performance). The internal_trace_puts() is for such
1407 * a purpose.
1408 */
1409#define internal_trace_puts(str) __trace_puts(_THIS_IP_, str, strlen(str))
1410
1411#undef FTRACE_ENTRY
1412#define FTRACE_ENTRY(call, struct_name, id, tstruct, print, filter)	\
1413	extern struct trace_event_call					\
1414	__aligned(4) event_##call;
1415#undef FTRACE_ENTRY_DUP
1416#define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print, filter)	\
1417	FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print), \
1418		     filter)
 
 
 
1419#include "trace_entries.h"
1420
1421#if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER)
1422int perf_ftrace_event_register(struct trace_event_call *call,
1423			       enum trace_reg type, void *data);
1424#else
1425#define perf_ftrace_event_register NULL
1426#endif
1427
1428#ifdef CONFIG_FTRACE_SYSCALLS
1429void init_ftrace_syscalls(void);
1430const char *get_syscall_name(int syscall);
1431#else
1432static inline void init_ftrace_syscalls(void) { }
1433static inline const char *get_syscall_name(int syscall)
1434{
1435	return NULL;
1436}
1437#endif
1438
1439#ifdef CONFIG_EVENT_TRACING
1440void trace_event_init(void);
1441void trace_event_enum_update(struct trace_enum_map **map, int len);
 
 
 
1442#else
1443static inline void __init trace_event_init(void) { }
1444static inline void trace_event_enum_update(struct trace_enum_map **map, int len) { }
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1445#endif
1446
1447extern struct trace_iterator *tracepoint_print_iter;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1448
1449#endif /* _LINUX_KERNEL_TRACE_H */