Linux Audio

Check our new training course

Loading...
v4.17
   1/*
   2 * trace_output.c
   3 *
   4 * Copyright (C) 2008 Red Hat Inc, Steven Rostedt <srostedt@redhat.com>
   5 *
   6 */
 
   7#include <linux/module.h>
   8#include <linux/mutex.h>
   9#include <linux/ftrace.h>
  10#include <linux/sched/clock.h>
  11#include <linux/sched/mm.h>
  12
  13#include "trace_output.h"
  14
  15/* must be a power of 2 */
  16#define EVENT_HASHSIZE	128
  17
  18DECLARE_RWSEM(trace_event_sem);
  19
  20static struct hlist_head event_hash[EVENT_HASHSIZE] __read_mostly;
  21
  22static int next_event_type = __TRACE_LAST_TYPE + 1;
  23
  24enum print_line_t trace_print_bputs_msg_only(struct trace_iterator *iter)
  25{
  26	struct trace_seq *s = &iter->seq;
  27	struct trace_entry *entry = iter->ent;
  28	struct bputs_entry *field;
  29
  30	trace_assign_type(field, entry);
  31
  32	trace_seq_puts(s, field->str);
 
 
 
 
 
  33
  34	return trace_handle_return(s);
  35}
  36
  37enum print_line_t trace_print_bprintk_msg_only(struct trace_iterator *iter)
  38{
  39	struct trace_seq *s = &iter->seq;
  40	struct trace_entry *entry = iter->ent;
  41	struct bprint_entry *field;
 
  42
  43	trace_assign_type(field, entry);
  44
  45	trace_seq_bprintf(s, field->fmt, field->buf);
 
 
  46
  47	return trace_handle_return(s);
  48}
  49
  50enum print_line_t trace_print_printk_msg_only(struct trace_iterator *iter)
  51{
  52	struct trace_seq *s = &iter->seq;
  53	struct trace_entry *entry = iter->ent;
  54	struct print_entry *field;
 
  55
  56	trace_assign_type(field, entry);
  57
  58	trace_seq_puts(s, field->buf);
 
 
  59
  60	return trace_handle_return(s);
  61}
  62
  63const char *
  64trace_print_flags_seq(struct trace_seq *p, const char *delim,
  65		      unsigned long flags,
  66		      const struct trace_print_flags *flag_array)
 
 
 
 
 
 
 
 
 
 
 
 
  67{
  68	unsigned long mask;
  69	const char *str;
  70	const char *ret = trace_seq_buffer_ptr(p);
  71	int i, first = 1;
  72
  73	for (i = 0;  flag_array[i].name && flags; i++) {
 
  74
  75		mask = flag_array[i].mask;
  76		if ((flags & mask) != mask)
  77			continue;
  78
  79		str = flag_array[i].name;
  80		flags &= ~mask;
  81		if (!first && delim)
  82			trace_seq_puts(p, delim);
  83		else
  84			first = 0;
  85		trace_seq_puts(p, str);
  86	}
  87
  88	/* check for left over flags */
  89	if (flags) {
  90		if (!first && delim)
  91			trace_seq_puts(p, delim);
  92		trace_seq_printf(p, "0x%lx", flags);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  93	}
  94
  95	trace_seq_putc(p, 0);
  96
  97	return ret;
  98}
  99EXPORT_SYMBOL(trace_print_flags_seq);
 100
 101const char *
 102trace_print_symbols_seq(struct trace_seq *p, unsigned long val,
 103			const struct trace_print_flags *symbol_array)
 104{
 105	int i;
 106	const char *ret = trace_seq_buffer_ptr(p);
 107
 108	for (i = 0;  symbol_array[i].name; i++) {
 
 109
 110		if (val != symbol_array[i].mask)
 111			continue;
 112
 113		trace_seq_puts(p, symbol_array[i].name);
 114		break;
 
 
 115	}
 116
 117	if (ret == (const char *)(trace_seq_buffer_ptr(p)))
 118		trace_seq_printf(p, "0x%lx", val);
 119
 120	trace_seq_putc(p, 0);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 121
 122	return ret;
 123}
 124EXPORT_SYMBOL(trace_print_symbols_seq);
 125
 126#if BITS_PER_LONG == 32
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 127const char *
 128trace_print_flags_seq_u64(struct trace_seq *p, const char *delim,
 129		      unsigned long long flags,
 130		      const struct trace_print_flags_u64 *flag_array)
 131{
 132	unsigned long long mask;
 133	const char *str;
 134	const char *ret = trace_seq_buffer_ptr(p);
 135	int i, first = 1;
 136
 137	for (i = 0;  flag_array[i].name && flags; i++) {
 138
 139		mask = flag_array[i].mask;
 140		if ((flags & mask) != mask)
 141			continue;
 142
 143		str = flag_array[i].name;
 144		flags &= ~mask;
 145		if (!first && delim)
 146			trace_seq_puts(p, delim);
 147		else
 148			first = 0;
 149		trace_seq_puts(p, str);
 150	}
 151
 152	/* check for left over flags */
 153	if (flags) {
 154		if (!first && delim)
 155			trace_seq_puts(p, delim);
 156		trace_seq_printf(p, "0x%llx", flags);
 157	}
 158
 159	trace_seq_putc(p, 0);
 160
 161	return ret;
 162}
 163EXPORT_SYMBOL(trace_print_flags_seq_u64);
 164
 165const char *
 166trace_print_symbols_seq_u64(struct trace_seq *p, unsigned long long val,
 167			 const struct trace_print_flags_u64 *symbol_array)
 168{
 169	int i;
 170	const char *ret = trace_seq_buffer_ptr(p);
 171
 172	for (i = 0;  symbol_array[i].name; i++) {
 173
 174		if (val != symbol_array[i].mask)
 175			continue;
 176
 177		trace_seq_puts(p, symbol_array[i].name);
 178		break;
 179	}
 180
 181	if (ret == (const char *)(trace_seq_buffer_ptr(p)))
 182		trace_seq_printf(p, "0x%llx", val);
 183
 184	trace_seq_putc(p, 0);
 185
 186	return ret;
 187}
 188EXPORT_SYMBOL(trace_print_symbols_seq_u64);
 189#endif
 190
 191const char *
 192trace_print_bitmask_seq(struct trace_seq *p, void *bitmask_ptr,
 193			unsigned int bitmask_size)
 194{
 195	const char *ret = trace_seq_buffer_ptr(p);
 196
 197	trace_seq_bitmask(p, bitmask_ptr, bitmask_size * 8);
 198	trace_seq_putc(p, 0);
 199
 200	return ret;
 201}
 202EXPORT_SYMBOL_GPL(trace_print_bitmask_seq);
 203
 204/**
 205 * trace_print_hex_seq - print buffer as hex sequence
 206 * @p: trace seq struct to write to
 207 * @buf: The buffer to print
 208 * @buf_len: Length of @buf in bytes
 209 * @concatenate: Print @buf as single hex string or with spacing
 210 *
 211 * Prints the passed buffer as a hex sequence either as a whole,
 212 * single hex string if @concatenate is true or with spacing after
 213 * each byte in case @concatenate is false.
 214 */
 215const char *
 216trace_print_hex_seq(struct trace_seq *p, const unsigned char *buf, int buf_len,
 217		    bool concatenate)
 218{
 219	int i;
 220	const char *ret = trace_seq_buffer_ptr(p);
 221
 222	for (i = 0; i < buf_len; i++)
 223		trace_seq_printf(p, "%s%2.2x", concatenate || i == 0 ? "" : " ",
 224				 buf[i]);
 225	trace_seq_putc(p, 0);
 226
 227	return ret;
 228}
 229EXPORT_SYMBOL(trace_print_hex_seq);
 230
 231const char *
 232trace_print_array_seq(struct trace_seq *p, const void *buf, int count,
 233		      size_t el_size)
 234{
 235	const char *ret = trace_seq_buffer_ptr(p);
 236	const char *prefix = "";
 237	void *ptr = (void *)buf;
 238	size_t buf_len = count * el_size;
 239
 240	trace_seq_putc(p, '{');
 241
 242	while (ptr < buf + buf_len) {
 243		switch (el_size) {
 244		case 1:
 245			trace_seq_printf(p, "%s0x%x", prefix,
 246					 *(u8 *)ptr);
 247			break;
 248		case 2:
 249			trace_seq_printf(p, "%s0x%x", prefix,
 250					 *(u16 *)ptr);
 251			break;
 252		case 4:
 253			trace_seq_printf(p, "%s0x%x", prefix,
 254					 *(u32 *)ptr);
 255			break;
 256		case 8:
 257			trace_seq_printf(p, "%s0x%llx", prefix,
 258					 *(u64 *)ptr);
 259			break;
 260		default:
 261			trace_seq_printf(p, "BAD SIZE:%zu 0x%x", el_size,
 262					 *(u8 *)ptr);
 263			el_size = 1;
 264		}
 265		prefix = ",";
 266		ptr += el_size;
 267	}
 268
 269	trace_seq_putc(p, '}');
 
 
 270	trace_seq_putc(p, 0);
 271
 272	return ret;
 273}
 274EXPORT_SYMBOL(trace_print_array_seq);
 275
 276int trace_raw_output_prep(struct trace_iterator *iter,
 277			  struct trace_event *trace_event)
 278{
 279	struct trace_event_call *event;
 280	struct trace_seq *s = &iter->seq;
 281	struct trace_seq *p = &iter->tmp_seq;
 282	struct trace_entry *entry;
 283
 284	event = container_of(trace_event, struct trace_event_call, event);
 285	entry = iter->ent;
 286
 287	if (entry->type != event->event.type) {
 288		WARN_ON_ONCE(1);
 289		return TRACE_TYPE_UNHANDLED;
 290	}
 291
 292	trace_seq_init(p);
 293	trace_seq_printf(s, "%s: ", trace_event_name(event));
 294
 295	return trace_handle_return(s);
 296}
 297EXPORT_SYMBOL(trace_raw_output_prep);
 298
 299static int trace_output_raw(struct trace_iterator *iter, char *name,
 300			    char *fmt, va_list ap)
 301{
 302	struct trace_seq *s = &iter->seq;
 303
 304	trace_seq_printf(s, "%s: ", name);
 305	trace_seq_vprintf(s, fmt, ap);
 306
 307	return trace_handle_return(s);
 308}
 309
 310int trace_output_call(struct trace_iterator *iter, char *name, char *fmt, ...)
 311{
 312	va_list ap;
 313	int ret;
 314
 315	va_start(ap, fmt);
 316	ret = trace_output_raw(iter, name, fmt, ap);
 317	va_end(ap);
 318
 319	return ret;
 320}
 321EXPORT_SYMBOL_GPL(trace_output_call);
 322
 323#ifdef CONFIG_KRETPROBES
 324static inline const char *kretprobed(const char *name)
 325{
 326	static const char tramp_name[] = "kretprobe_trampoline";
 327	int size = sizeof(tramp_name);
 328
 329	if (strncmp(tramp_name, name, size) == 0)
 330		return "[unknown/kretprobe'd]";
 331	return name;
 332}
 333#else
 334static inline const char *kretprobed(const char *name)
 335{
 336	return name;
 337}
 338#endif /* CONFIG_KRETPROBES */
 339
 340static void
 341seq_print_sym_short(struct trace_seq *s, const char *fmt, unsigned long address)
 342{
 343	char str[KSYM_SYMBOL_LEN];
 344#ifdef CONFIG_KALLSYMS
 
 345	const char *name;
 346
 347	kallsyms_lookup(address, NULL, NULL, NULL, str);
 348
 349	name = kretprobed(str);
 350
 351	if (name && strlen(name)) {
 352		trace_seq_printf(s, fmt, name);
 353		return;
 354	}
 355#endif
 356	snprintf(str, KSYM_SYMBOL_LEN, "0x%08lx", address);
 357	trace_seq_printf(s, fmt, str);
 358}
 359
 360static void
 361seq_print_sym_offset(struct trace_seq *s, const char *fmt,
 362		     unsigned long address)
 363{
 364	char str[KSYM_SYMBOL_LEN];
 365#ifdef CONFIG_KALLSYMS
 
 366	const char *name;
 367
 368	sprint_symbol(str, address);
 369	name = kretprobed(str);
 370
 371	if (name && strlen(name)) {
 372		trace_seq_printf(s, fmt, name);
 373		return;
 374	}
 375#endif
 376	snprintf(str, KSYM_SYMBOL_LEN, "0x%08lx", address);
 377	trace_seq_printf(s, fmt, str);
 378}
 379
 380#ifndef CONFIG_64BIT
 381# define IP_FMT "%08lx"
 382#else
 383# define IP_FMT "%016lx"
 384#endif
 385
 386static int seq_print_user_ip(struct trace_seq *s, struct mm_struct *mm,
 387			     unsigned long ip, unsigned long sym_flags)
 388{
 389	struct file *file = NULL;
 390	unsigned long vmstart = 0;
 391	int ret = 1;
 392
 393	if (s->full)
 394		return 0;
 395
 396	if (mm) {
 397		const struct vm_area_struct *vma;
 398
 399		down_read(&mm->mmap_sem);
 400		vma = find_vma(mm, ip);
 401		if (vma) {
 402			file = vma->vm_file;
 403			vmstart = vma->vm_start;
 404		}
 405		if (file) {
 406			ret = trace_seq_path(s, &file->f_path);
 407			if (ret)
 408				trace_seq_printf(s, "[+0x%lx]",
 409						 ip - vmstart);
 410		}
 411		up_read(&mm->mmap_sem);
 412	}
 413	if (ret && ((sym_flags & TRACE_ITER_SYM_ADDR) || !file))
 414		trace_seq_printf(s, " <" IP_FMT ">", ip);
 415	return !trace_seq_has_overflowed(s);
 416}
 417
 418int
 419seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags)
 
 420{
 421	if (!ip) {
 422		trace_seq_putc(s, '0');
 423		goto out;
 
 
 
 
 
 
 
 
 
 
 
 
 424	}
 425
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 426	if (sym_flags & TRACE_ITER_SYM_OFFSET)
 427		seq_print_sym_offset(s, "%s", ip);
 428	else
 429		seq_print_sym_short(s, "%s", ip);
 430
 431	if (sym_flags & TRACE_ITER_SYM_ADDR)
 432		trace_seq_printf(s, " <" IP_FMT ">", ip);
 433
 434 out:
 435	return !trace_seq_has_overflowed(s);
 
 436}
 437
 438/**
 439 * trace_print_lat_fmt - print the irq, preempt and lockdep fields
 440 * @s: trace seq struct to write to
 441 * @entry: The trace entry field from the ring buffer
 442 *
 443 * Prints the generic fields of irqs off, in hard or softirq, preempt
 444 * count.
 445 */
 446int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
 447{
 448	char hardsoft_irq;
 449	char need_resched;
 450	char irqs_off;
 451	int hardirq;
 452	int softirq;
 453	int nmi;
 454
 455	nmi = entry->flags & TRACE_FLAG_NMI;
 456	hardirq = entry->flags & TRACE_FLAG_HARDIRQ;
 457	softirq = entry->flags & TRACE_FLAG_SOFTIRQ;
 458
 459	irqs_off =
 460		(entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' :
 461		(entry->flags & TRACE_FLAG_IRQS_NOSUPPORT) ? 'X' :
 462		'.';
 463
 464	switch (entry->flags & (TRACE_FLAG_NEED_RESCHED |
 465				TRACE_FLAG_PREEMPT_RESCHED)) {
 466	case TRACE_FLAG_NEED_RESCHED | TRACE_FLAG_PREEMPT_RESCHED:
 467		need_resched = 'N';
 468		break;
 469	case TRACE_FLAG_NEED_RESCHED:
 470		need_resched = 'n';
 471		break;
 472	case TRACE_FLAG_PREEMPT_RESCHED:
 473		need_resched = 'p';
 474		break;
 475	default:
 476		need_resched = '.';
 477		break;
 478	}
 479
 480	hardsoft_irq =
 481		(nmi && hardirq)     ? 'Z' :
 482		nmi                  ? 'z' :
 483		(hardirq && softirq) ? 'H' :
 484		hardirq              ? 'h' :
 485		softirq              ? 's' :
 486		                       '.' ;
 487
 488	trace_seq_printf(s, "%c%c%c",
 489			 irqs_off, need_resched, hardsoft_irq);
 
 490
 491	if (entry->preempt_count)
 492		trace_seq_printf(s, "%x", entry->preempt_count);
 493	else
 494		trace_seq_putc(s, '.');
 495
 496	return !trace_seq_has_overflowed(s);
 497}
 498
 499static int
 500lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu)
 501{
 502	char comm[TASK_COMM_LEN];
 503
 504	trace_find_cmdline(entry->pid, comm);
 505
 506	trace_seq_printf(s, "%8.8s-%-5d %3d",
 507			 comm, entry->pid, cpu);
 
 508
 509	return trace_print_lat_fmt(s, entry);
 510}
 511
 512#undef MARK
 513#define MARK(v, s) {.val = v, .sym = s}
 514/* trace overhead mark */
 515static const struct trace_mark {
 516	unsigned long long	val; /* unit: nsec */
 517	char			sym;
 518} mark[] = {
 519	MARK(1000000000ULL	, '$'), /* 1 sec */
 520	MARK(100000000ULL	, '@'), /* 100 msec */
 521	MARK(10000000ULL	, '*'), /* 10 msec */
 522	MARK(1000000ULL		, '#'), /* 1000 usecs */
 523	MARK(100000ULL		, '!'), /* 100 usecs */
 524	MARK(10000ULL		, '+'), /* 10 usecs */
 525};
 526#undef MARK
 527
 528char trace_find_mark(unsigned long long d)
 529{
 530	int i;
 531	int size = ARRAY_SIZE(mark);
 532
 533	for (i = 0; i < size; i++) {
 534		if (d > mark[i].val)
 535			break;
 536	}
 537
 538	return (i == size) ? ' ' : mark[i].sym;
 539}
 540
 541static int
 542lat_print_timestamp(struct trace_iterator *iter, u64 next_ts)
 
 543{
 544	struct trace_array *tr = iter->tr;
 545	unsigned long verbose = tr->trace_flags & TRACE_ITER_VERBOSE;
 546	unsigned long in_ns = iter->iter_flags & TRACE_FILE_TIME_IN_NS;
 547	unsigned long long abs_ts = iter->ts - iter->trace_buffer->time_start;
 548	unsigned long long rel_ts = next_ts - iter->ts;
 549	struct trace_seq *s = &iter->seq;
 550
 551	if (in_ns) {
 552		abs_ts = ns2usecs(abs_ts);
 553		rel_ts = ns2usecs(rel_ts);
 554	}
 555
 556	if (verbose && in_ns) {
 557		unsigned long abs_usec = do_div(abs_ts, USEC_PER_MSEC);
 558		unsigned long abs_msec = (unsigned long)abs_ts;
 559		unsigned long rel_usec = do_div(rel_ts, USEC_PER_MSEC);
 560		unsigned long rel_msec = (unsigned long)rel_ts;
 561
 562		trace_seq_printf(
 563			s, "[%08llx] %ld.%03ldms (+%ld.%03ldms): ",
 564			ns2usecs(iter->ts),
 565			abs_msec, abs_usec,
 566			rel_msec, rel_usec);
 567
 568	} else if (verbose && !in_ns) {
 569		trace_seq_printf(
 570			s, "[%016llx] %lld (+%lld): ",
 571			iter->ts, abs_ts, rel_ts);
 572
 573	} else if (!verbose && in_ns) {
 574		trace_seq_printf(
 575			s, " %4lldus%c: ",
 576			abs_ts,
 577			trace_find_mark(rel_ts * NSEC_PER_USEC));
 578
 579	} else { /* !verbose && !in_ns */
 580		trace_seq_printf(s, " %4lld: ", abs_ts);
 581	}
 582
 583	return !trace_seq_has_overflowed(s);
 584}
 585
 586int trace_print_context(struct trace_iterator *iter)
 587{
 588	struct trace_array *tr = iter->tr;
 589	struct trace_seq *s = &iter->seq;
 590	struct trace_entry *entry = iter->ent;
 591	unsigned long long t;
 592	unsigned long secs, usec_rem;
 
 593	char comm[TASK_COMM_LEN];
 594
 595	trace_find_cmdline(entry->pid, comm);
 596
 597	trace_seq_printf(s, "%16s-%-5d [%03d] ",
 598			       comm, entry->pid, iter->cpu);
 599
 600	if (tr->trace_flags & TRACE_ITER_RECORD_TGID) {
 601		unsigned int tgid = trace_find_tgid(entry->pid);
 602
 603		if (!tgid)
 604			trace_seq_printf(s, "(-----) ");
 605		else
 606			trace_seq_printf(s, "(%5d) ", tgid);
 607	}
 608
 609	if (tr->trace_flags & TRACE_ITER_IRQ_INFO)
 610		trace_print_lat_fmt(s, entry);
 611
 612	if (iter->iter_flags & TRACE_FILE_TIME_IN_NS) {
 613		t = ns2usecs(iter->ts);
 614		usec_rem = do_div(t, USEC_PER_SEC);
 615		secs = (unsigned long)t;
 616		trace_seq_printf(s, " %5lu.%06lu: ", secs, usec_rem);
 617	} else
 618		trace_seq_printf(s, " %12llu: ", iter->ts);
 619
 620	return !trace_seq_has_overflowed(s);
 621}
 622
 623int trace_print_lat_context(struct trace_iterator *iter)
 624{
 625	struct trace_array *tr = iter->tr;
 626	/* trace_find_next_entry will reset ent_size */
 627	int ent_size = iter->ent_size;
 628	struct trace_seq *s = &iter->seq;
 629	u64 next_ts;
 
 
 630	struct trace_entry *entry = iter->ent,
 631			   *next_entry = trace_find_next_entry(iter, NULL,
 632							       &next_ts);
 633	unsigned long verbose = (tr->trace_flags & TRACE_ITER_VERBOSE);
 634
 635	/* Restore the original ent_size */
 636	iter->ent_size = ent_size;
 637
 638	if (!next_entry)
 639		next_ts = iter->ts;
 
 640
 641	if (verbose) {
 642		char comm[TASK_COMM_LEN];
 643
 644		trace_find_cmdline(entry->pid, comm);
 645
 646		trace_seq_printf(
 647			s, "%16s %5d %3d %d %08x %08lx ",
 648			comm, entry->pid, iter->cpu, entry->flags,
 649			entry->preempt_count, iter->idx);
 
 
 
 
 
 650	} else {
 651		lat_print_generic(s, entry, iter->cpu);
 
 
 652	}
 653
 654	lat_print_timestamp(iter, next_ts);
 
 
 
 
 
 
 
 655
 656	return !trace_seq_has_overflowed(s);
 657}
 658
 659/**
 660 * ftrace_find_event - find a registered event
 661 * @type: the type of event to look for
 662 *
 663 * Returns an event of type @type otherwise NULL
 664 * Called with trace_event_read_lock() held.
 665 */
 666struct trace_event *ftrace_find_event(int type)
 667{
 668	struct trace_event *event;
 
 669	unsigned key;
 670
 671	key = type & (EVENT_HASHSIZE - 1);
 672
 673	hlist_for_each_entry(event, &event_hash[key], node) {
 674		if (event->type == type)
 675			return event;
 676	}
 677
 678	return NULL;
 679}
 680
 681static LIST_HEAD(ftrace_event_list);
 682
 683static int trace_search_list(struct list_head **list)
 684{
 685	struct trace_event *e;
 686	int last = __TRACE_LAST_TYPE;
 687
 688	if (list_empty(&ftrace_event_list)) {
 689		*list = &ftrace_event_list;
 690		return last + 1;
 691	}
 692
 693	/*
 694	 * We used up all possible max events,
 695	 * lets see if somebody freed one.
 696	 */
 697	list_for_each_entry(e, &ftrace_event_list, list) {
 698		if (e->type != last + 1)
 699			break;
 700		last++;
 701	}
 702
 703	/* Did we used up all 65 thousand events??? */
 704	if ((last + 1) > TRACE_EVENT_TYPE_MAX)
 705		return 0;
 706
 707	*list = &e->list;
 708	return last + 1;
 709}
 710
 711void trace_event_read_lock(void)
 712{
 713	down_read(&trace_event_sem);
 714}
 715
 716void trace_event_read_unlock(void)
 717{
 718	up_read(&trace_event_sem);
 719}
 720
 721/**
 722 * register_trace_event - register output for an event type
 723 * @event: the event type to register
 724 *
 725 * Event types are stored in a hash and this hash is used to
 726 * find a way to print an event. If the @event->type is set
 727 * then it will use that type, otherwise it will assign a
 728 * type to use.
 729 *
 730 * If you assign your own type, please make sure it is added
 731 * to the trace_type enum in trace.h, to avoid collisions
 732 * with the dynamic types.
 733 *
 734 * Returns the event type number or zero on error.
 735 */
 736int register_trace_event(struct trace_event *event)
 737{
 738	unsigned key;
 739	int ret = 0;
 740
 741	down_write(&trace_event_sem);
 742
 743	if (WARN_ON(!event))
 744		goto out;
 745
 746	if (WARN_ON(!event->funcs))
 747		goto out;
 748
 749	INIT_LIST_HEAD(&event->list);
 750
 751	if (!event->type) {
 752		struct list_head *list = NULL;
 753
 754		if (next_event_type > TRACE_EVENT_TYPE_MAX) {
 755
 756			event->type = trace_search_list(&list);
 757			if (!event->type)
 758				goto out;
 759
 760		} else {
 761
 762			event->type = next_event_type++;
 763			list = &ftrace_event_list;
 764		}
 765
 766		if (WARN_ON(ftrace_find_event(event->type)))
 767			goto out;
 768
 769		list_add_tail(&event->list, list);
 770
 771	} else if (event->type > __TRACE_LAST_TYPE) {
 772		printk(KERN_WARNING "Need to add type to trace.h\n");
 773		WARN_ON(1);
 774		goto out;
 775	} else {
 776		/* Is this event already used */
 777		if (ftrace_find_event(event->type))
 778			goto out;
 779	}
 780
 781	if (event->funcs->trace == NULL)
 782		event->funcs->trace = trace_nop_print;
 783	if (event->funcs->raw == NULL)
 784		event->funcs->raw = trace_nop_print;
 785	if (event->funcs->hex == NULL)
 786		event->funcs->hex = trace_nop_print;
 787	if (event->funcs->binary == NULL)
 788		event->funcs->binary = trace_nop_print;
 789
 790	key = event->type & (EVENT_HASHSIZE - 1);
 791
 792	hlist_add_head(&event->node, &event_hash[key]);
 793
 794	ret = event->type;
 795 out:
 796	up_write(&trace_event_sem);
 797
 798	return ret;
 799}
 800EXPORT_SYMBOL_GPL(register_trace_event);
 801
 802/*
 803 * Used by module code with the trace_event_sem held for write.
 804 */
 805int __unregister_trace_event(struct trace_event *event)
 806{
 807	hlist_del(&event->node);
 808	list_del(&event->list);
 809	return 0;
 810}
 811
 812/**
 813 * unregister_trace_event - remove a no longer used event
 814 * @event: the event to remove
 815 */
 816int unregister_trace_event(struct trace_event *event)
 817{
 818	down_write(&trace_event_sem);
 819	__unregister_trace_event(event);
 820	up_write(&trace_event_sem);
 821
 822	return 0;
 823}
 824EXPORT_SYMBOL_GPL(unregister_trace_event);
 825
 826/*
 827 * Standard events
 828 */
 829
 830enum print_line_t trace_nop_print(struct trace_iterator *iter, int flags,
 831				  struct trace_event *event)
 832{
 833	trace_seq_printf(&iter->seq, "type: %d\n", iter->ent->type);
 
 834
 835	return trace_handle_return(&iter->seq);
 836}
 837
 838/* TRACE_FN */
 839static enum print_line_t trace_fn_trace(struct trace_iterator *iter, int flags,
 840					struct trace_event *event)
 841{
 842	struct ftrace_entry *field;
 843	struct trace_seq *s = &iter->seq;
 844
 845	trace_assign_type(field, iter->ent);
 846
 847	seq_print_ip_sym(s, field->ip, flags);
 
 848
 849	if ((flags & TRACE_ITER_PRINT_PARENT) && field->parent_ip) {
 850		trace_seq_puts(s, " <-");
 851		seq_print_ip_sym(s, field->parent_ip, flags);
 
 
 
 
 852	}
 
 
 853
 854	trace_seq_putc(s, '\n');
 855
 856	return trace_handle_return(s);
 
 857}
 858
 859static enum print_line_t trace_fn_raw(struct trace_iterator *iter, int flags,
 860				      struct trace_event *event)
 861{
 862	struct ftrace_entry *field;
 863
 864	trace_assign_type(field, iter->ent);
 865
 866	trace_seq_printf(&iter->seq, "%lx %lx\n",
 867			 field->ip,
 868			 field->parent_ip);
 
 869
 870	return trace_handle_return(&iter->seq);
 871}
 872
 873static enum print_line_t trace_fn_hex(struct trace_iterator *iter, int flags,
 874				      struct trace_event *event)
 875{
 876	struct ftrace_entry *field;
 877	struct trace_seq *s = &iter->seq;
 878
 879	trace_assign_type(field, iter->ent);
 880
 881	SEQ_PUT_HEX_FIELD(s, field->ip);
 882	SEQ_PUT_HEX_FIELD(s, field->parent_ip);
 883
 884	return trace_handle_return(s);
 885}
 886
 887static enum print_line_t trace_fn_bin(struct trace_iterator *iter, int flags,
 888				      struct trace_event *event)
 889{
 890	struct ftrace_entry *field;
 891	struct trace_seq *s = &iter->seq;
 892
 893	trace_assign_type(field, iter->ent);
 894
 895	SEQ_PUT_FIELD(s, field->ip);
 896	SEQ_PUT_FIELD(s, field->parent_ip);
 897
 898	return trace_handle_return(s);
 899}
 900
 901static struct trace_event_functions trace_fn_funcs = {
 902	.trace		= trace_fn_trace,
 903	.raw		= trace_fn_raw,
 904	.hex		= trace_fn_hex,
 905	.binary		= trace_fn_bin,
 906};
 907
 908static struct trace_event trace_fn_event = {
 909	.type		= TRACE_FN,
 910	.funcs		= &trace_fn_funcs,
 911};
 912
 913/* TRACE_CTX an TRACE_WAKE */
 914static enum print_line_t trace_ctxwake_print(struct trace_iterator *iter,
 915					     char *delim)
 916{
 917	struct ctx_switch_entry *field;
 918	char comm[TASK_COMM_LEN];
 919	int S, T;
 920
 921
 922	trace_assign_type(field, iter->ent);
 923
 924	T = task_index_to_char(field->next_state);
 925	S = task_index_to_char(field->prev_state);
 926	trace_find_cmdline(field->next_pid, comm);
 927	trace_seq_printf(&iter->seq,
 928			 " %5d:%3d:%c %s [%03d] %5d:%3d:%c %s\n",
 929			 field->prev_pid,
 930			 field->prev_prio,
 931			 S, delim,
 932			 field->next_cpu,
 933			 field->next_pid,
 934			 field->next_prio,
 935			 T, comm);
 
 936
 937	return trace_handle_return(&iter->seq);
 938}
 939
 940static enum print_line_t trace_ctx_print(struct trace_iterator *iter, int flags,
 941					 struct trace_event *event)
 942{
 943	return trace_ctxwake_print(iter, "==>");
 944}
 945
 946static enum print_line_t trace_wake_print(struct trace_iterator *iter,
 947					  int flags, struct trace_event *event)
 948{
 949	return trace_ctxwake_print(iter, "  +");
 950}
 951
 952static int trace_ctxwake_raw(struct trace_iterator *iter, char S)
 953{
 954	struct ctx_switch_entry *field;
 955	int T;
 956
 957	trace_assign_type(field, iter->ent);
 958
 959	if (!S)
 960		S = task_index_to_char(field->prev_state);
 961	T = task_index_to_char(field->next_state);
 962	trace_seq_printf(&iter->seq, "%d %d %c %d %d %d %c\n",
 963			 field->prev_pid,
 964			 field->prev_prio,
 965			 S,
 966			 field->next_cpu,
 967			 field->next_pid,
 968			 field->next_prio,
 969			 T);
 
 970
 971	return trace_handle_return(&iter->seq);
 972}
 973
 974static enum print_line_t trace_ctx_raw(struct trace_iterator *iter, int flags,
 975				       struct trace_event *event)
 976{
 977	return trace_ctxwake_raw(iter, 0);
 978}
 979
 980static enum print_line_t trace_wake_raw(struct trace_iterator *iter, int flags,
 981					struct trace_event *event)
 982{
 983	return trace_ctxwake_raw(iter, '+');
 984}
 985
 986
 987static int trace_ctxwake_hex(struct trace_iterator *iter, char S)
 988{
 989	struct ctx_switch_entry *field;
 990	struct trace_seq *s = &iter->seq;
 991	int T;
 992
 993	trace_assign_type(field, iter->ent);
 994
 995	if (!S)
 996		S = task_index_to_char(field->prev_state);
 997	T = task_index_to_char(field->next_state);
 998
 999	SEQ_PUT_HEX_FIELD(s, field->prev_pid);
1000	SEQ_PUT_HEX_FIELD(s, field->prev_prio);
1001	SEQ_PUT_HEX_FIELD(s, S);
1002	SEQ_PUT_HEX_FIELD(s, field->next_cpu);
1003	SEQ_PUT_HEX_FIELD(s, field->next_pid);
1004	SEQ_PUT_HEX_FIELD(s, field->next_prio);
1005	SEQ_PUT_HEX_FIELD(s, T);
1006
1007	return trace_handle_return(s);
1008}
1009
1010static enum print_line_t trace_ctx_hex(struct trace_iterator *iter, int flags,
1011				       struct trace_event *event)
1012{
1013	return trace_ctxwake_hex(iter, 0);
1014}
1015
1016static enum print_line_t trace_wake_hex(struct trace_iterator *iter, int flags,
1017					struct trace_event *event)
1018{
1019	return trace_ctxwake_hex(iter, '+');
1020}
1021
1022static enum print_line_t trace_ctxwake_bin(struct trace_iterator *iter,
1023					   int flags, struct trace_event *event)
1024{
1025	struct ctx_switch_entry *field;
1026	struct trace_seq *s = &iter->seq;
1027
1028	trace_assign_type(field, iter->ent);
1029
1030	SEQ_PUT_FIELD(s, field->prev_pid);
1031	SEQ_PUT_FIELD(s, field->prev_prio);
1032	SEQ_PUT_FIELD(s, field->prev_state);
1033	SEQ_PUT_FIELD(s, field->next_cpu);
1034	SEQ_PUT_FIELD(s, field->next_pid);
1035	SEQ_PUT_FIELD(s, field->next_prio);
1036	SEQ_PUT_FIELD(s, field->next_state);
1037
1038	return trace_handle_return(s);
1039}
1040
1041static struct trace_event_functions trace_ctx_funcs = {
1042	.trace		= trace_ctx_print,
1043	.raw		= trace_ctx_raw,
1044	.hex		= trace_ctx_hex,
1045	.binary		= trace_ctxwake_bin,
1046};
1047
1048static struct trace_event trace_ctx_event = {
1049	.type		= TRACE_CTX,
1050	.funcs		= &trace_ctx_funcs,
1051};
1052
1053static struct trace_event_functions trace_wake_funcs = {
1054	.trace		= trace_wake_print,
1055	.raw		= trace_wake_raw,
1056	.hex		= trace_wake_hex,
1057	.binary		= trace_ctxwake_bin,
1058};
1059
1060static struct trace_event trace_wake_event = {
1061	.type		= TRACE_WAKE,
1062	.funcs		= &trace_wake_funcs,
1063};
1064
1065/* TRACE_STACK */
1066
1067static enum print_line_t trace_stack_print(struct trace_iterator *iter,
1068					   int flags, struct trace_event *event)
1069{
1070	struct stack_entry *field;
1071	struct trace_seq *s = &iter->seq;
1072	unsigned long *p;
1073	unsigned long *end;
1074
1075	trace_assign_type(field, iter->ent);
1076	end = (unsigned long *)((long)iter->ent + iter->ent_size);
1077
1078	trace_seq_puts(s, "<stack trace>\n");
 
1079
1080	for (p = field->caller; p && *p != ULONG_MAX && p < end; p++) {
 
 
1081
1082		if (trace_seq_has_overflowed(s))
1083			break;
1084
1085		trace_seq_puts(s, " => ");
1086		seq_print_ip_sym(s, *p, flags);
1087		trace_seq_putc(s, '\n');
1088	}
1089
1090	return trace_handle_return(s);
 
 
 
1091}
1092
1093static struct trace_event_functions trace_stack_funcs = {
1094	.trace		= trace_stack_print,
1095};
1096
1097static struct trace_event trace_stack_event = {
1098	.type		= TRACE_STACK,
1099	.funcs		= &trace_stack_funcs,
1100};
1101
1102/* TRACE_USER_STACK */
1103static enum print_line_t trace_user_stack_print(struct trace_iterator *iter,
1104						int flags, struct trace_event *event)
1105{
1106	struct trace_array *tr = iter->tr;
1107	struct userstack_entry *field;
1108	struct trace_seq *s = &iter->seq;
1109	struct mm_struct *mm = NULL;
1110	unsigned int i;
1111
1112	trace_assign_type(field, iter->ent);
1113
1114	trace_seq_puts(s, "<user stack trace>\n");
1115
1116	if (tr->trace_flags & TRACE_ITER_SYM_USEROBJ) {
1117		struct task_struct *task;
1118		/*
1119		 * we do the lookup on the thread group leader,
1120		 * since individual threads might have already quit!
1121		 */
1122		rcu_read_lock();
1123		task = find_task_by_vpid(field->tgid);
1124		if (task)
1125			mm = get_task_mm(task);
1126		rcu_read_unlock();
1127	}
1128
1129	for (i = 0; i < FTRACE_STACK_ENTRIES; i++) {
1130		unsigned long ip = field->caller[i];
1131
1132		if (ip == ULONG_MAX || trace_seq_has_overflowed(s))
1133			break;
1134
1135		trace_seq_puts(s, " => ");
1136
1137		if (!ip) {
1138			trace_seq_puts(s, "??");
1139			trace_seq_putc(s, '\n');
1140			continue;
1141		}
1142
1143		seq_print_user_ip(s, mm, ip, flags);
1144		trace_seq_putc(s, '\n');
1145	}
1146
1147	if (mm)
1148		mmput(mm);
1149
1150	return trace_handle_return(s);
1151}
1152
1153static struct trace_event_functions trace_user_stack_funcs = {
1154	.trace		= trace_user_stack_print,
1155};
1156
1157static struct trace_event trace_user_stack_event = {
1158	.type		= TRACE_USER_STACK,
1159	.funcs		= &trace_user_stack_funcs,
1160};
1161
1162/* TRACE_HWLAT */
1163static enum print_line_t
1164trace_hwlat_print(struct trace_iterator *iter, int flags,
1165		  struct trace_event *event)
1166{
1167	struct trace_entry *entry = iter->ent;
1168	struct trace_seq *s = &iter->seq;
1169	struct hwlat_entry *field;
1170
1171	trace_assign_type(field, entry);
1172
1173	trace_seq_printf(s, "#%-5u inner/outer(us): %4llu/%-5llu ts:%lld.%09ld",
1174			 field->seqnum,
1175			 field->duration,
1176			 field->outer_duration,
1177			 (long long)field->timestamp.tv_sec,
1178			 field->timestamp.tv_nsec);
1179
1180	if (field->nmi_count) {
1181		/*
1182		 * The generic sched_clock() is not NMI safe, thus
1183		 * we only record the count and not the time.
1184		 */
1185		if (!IS_ENABLED(CONFIG_GENERIC_SCHED_CLOCK))
1186			trace_seq_printf(s, " nmi-total:%llu",
1187					 field->nmi_total_ts);
1188		trace_seq_printf(s, " nmi-count:%u",
1189				 field->nmi_count);
1190	}
1191
1192	trace_seq_putc(s, '\n');
1193
1194	return trace_handle_return(s);
1195}
1196
1197
1198static enum print_line_t
1199trace_hwlat_raw(struct trace_iterator *iter, int flags,
1200		struct trace_event *event)
1201{
1202	struct hwlat_entry *field;
1203	struct trace_seq *s = &iter->seq;
1204
1205	trace_assign_type(field, iter->ent);
1206
1207	trace_seq_printf(s, "%llu %lld %lld %09ld %u\n",
1208			 field->duration,
1209			 field->outer_duration,
1210			 (long long)field->timestamp.tv_sec,
1211			 field->timestamp.tv_nsec,
1212			 field->seqnum);
1213
1214	return trace_handle_return(s);
1215}
1216
1217static struct trace_event_functions trace_hwlat_funcs = {
1218	.trace		= trace_hwlat_print,
1219	.raw		= trace_hwlat_raw,
1220};
1221
1222static struct trace_event trace_hwlat_event = {
1223	.type		= TRACE_HWLAT,
1224	.funcs		= &trace_hwlat_funcs,
1225};
1226
1227/* TRACE_BPUTS */
1228static enum print_line_t
1229trace_bputs_print(struct trace_iterator *iter, int flags,
1230		   struct trace_event *event)
1231{
1232	struct trace_entry *entry = iter->ent;
1233	struct trace_seq *s = &iter->seq;
1234	struct bputs_entry *field;
1235
1236	trace_assign_type(field, entry);
1237
1238	seq_print_ip_sym(s, field->ip, flags);
1239	trace_seq_puts(s, ": ");
1240	trace_seq_puts(s, field->str);
1241
1242	return trace_handle_return(s);
1243}
1244
1245
1246static enum print_line_t
1247trace_bputs_raw(struct trace_iterator *iter, int flags,
1248		struct trace_event *event)
1249{
1250	struct bputs_entry *field;
1251	struct trace_seq *s = &iter->seq;
1252
1253	trace_assign_type(field, iter->ent);
1254
1255	trace_seq_printf(s, ": %lx : ", field->ip);
1256	trace_seq_puts(s, field->str);
1257
1258	return trace_handle_return(s);
1259}
1260
1261static struct trace_event_functions trace_bputs_funcs = {
1262	.trace		= trace_bputs_print,
1263	.raw		= trace_bputs_raw,
1264};
1265
1266static struct trace_event trace_bputs_event = {
1267	.type		= TRACE_BPUTS,
1268	.funcs		= &trace_bputs_funcs,
1269};
1270
1271/* TRACE_BPRINT */
1272static enum print_line_t
1273trace_bprint_print(struct trace_iterator *iter, int flags,
1274		   struct trace_event *event)
1275{
1276	struct trace_entry *entry = iter->ent;
1277	struct trace_seq *s = &iter->seq;
1278	struct bprint_entry *field;
1279
1280	trace_assign_type(field, entry);
1281
1282	seq_print_ip_sym(s, field->ip, flags);
1283	trace_seq_puts(s, ": ");
1284	trace_seq_bprintf(s, field->fmt, field->buf);
 
 
 
 
 
1285
1286	return trace_handle_return(s);
 
 
 
1287}
1288
1289
1290static enum print_line_t
1291trace_bprint_raw(struct trace_iterator *iter, int flags,
1292		 struct trace_event *event)
1293{
1294	struct bprint_entry *field;
1295	struct trace_seq *s = &iter->seq;
1296
1297	trace_assign_type(field, iter->ent);
1298
1299	trace_seq_printf(s, ": %lx : ", field->ip);
1300	trace_seq_bprintf(s, field->fmt, field->buf);
 
 
 
 
 
1301
1302	return trace_handle_return(s);
 
1303}
1304
1305static struct trace_event_functions trace_bprint_funcs = {
1306	.trace		= trace_bprint_print,
1307	.raw		= trace_bprint_raw,
1308};
1309
1310static struct trace_event trace_bprint_event = {
1311	.type		= TRACE_BPRINT,
1312	.funcs		= &trace_bprint_funcs,
1313};
1314
1315/* TRACE_PRINT */
1316static enum print_line_t trace_print_print(struct trace_iterator *iter,
1317					   int flags, struct trace_event *event)
1318{
1319	struct print_entry *field;
1320	struct trace_seq *s = &iter->seq;
1321
1322	trace_assign_type(field, iter->ent);
1323
1324	seq_print_ip_sym(s, field->ip, flags);
1325	trace_seq_printf(s, ": %s", field->buf);
1326
1327	return trace_handle_return(s);
 
 
 
 
 
 
1328}
1329
1330static enum print_line_t trace_print_raw(struct trace_iterator *iter, int flags,
1331					 struct trace_event *event)
1332{
1333	struct print_entry *field;
1334
1335	trace_assign_type(field, iter->ent);
1336
1337	trace_seq_printf(&iter->seq, "# %lx %s", field->ip, field->buf);
 
 
 
1338
1339	return trace_handle_return(&iter->seq);
 
1340}
1341
1342static struct trace_event_functions trace_print_funcs = {
1343	.trace		= trace_print_print,
1344	.raw		= trace_print_raw,
1345};
1346
1347static struct trace_event trace_print_event = {
1348	.type	 	= TRACE_PRINT,
1349	.funcs		= &trace_print_funcs,
1350};
1351
1352static enum print_line_t trace_raw_data(struct trace_iterator *iter, int flags,
1353					 struct trace_event *event)
1354{
1355	struct raw_data_entry *field;
1356	int i;
1357
1358	trace_assign_type(field, iter->ent);
1359
1360	trace_seq_printf(&iter->seq, "# %x buf:", field->id);
1361
1362	for (i = 0; i < iter->ent_size - offsetof(struct raw_data_entry, buf); i++)
1363		trace_seq_printf(&iter->seq, " %02x",
1364				 (unsigned char)field->buf[i]);
1365
1366	trace_seq_putc(&iter->seq, '\n');
1367
1368	return trace_handle_return(&iter->seq);
1369}
1370
1371static struct trace_event_functions trace_raw_data_funcs = {
1372	.trace		= trace_raw_data,
1373	.raw		= trace_raw_data,
1374};
1375
1376static struct trace_event trace_raw_data_event = {
1377	.type	 	= TRACE_RAW_DATA,
1378	.funcs		= &trace_raw_data_funcs,
1379};
1380
1381
1382static struct trace_event *events[] __initdata = {
1383	&trace_fn_event,
1384	&trace_ctx_event,
1385	&trace_wake_event,
1386	&trace_stack_event,
1387	&trace_user_stack_event,
1388	&trace_bputs_event,
1389	&trace_bprint_event,
1390	&trace_print_event,
1391	&trace_hwlat_event,
1392	&trace_raw_data_event,
1393	NULL
1394};
1395
1396__init static int init_events(void)
1397{
1398	struct trace_event *event;
1399	int i, ret;
1400
1401	for (i = 0; events[i]; i++) {
1402		event = events[i];
1403
1404		ret = register_trace_event(event);
1405		if (!ret) {
1406			printk(KERN_WARNING "event %d failed to register\n",
1407			       event->type);
1408			WARN_ON_ONCE(1);
1409		}
1410	}
1411
1412	return 0;
1413}
1414early_initcall(init_events);
v3.1
   1/*
   2 * trace_output.c
   3 *
   4 * Copyright (C) 2008 Red Hat Inc, Steven Rostedt <srostedt@redhat.com>
   5 *
   6 */
   7
   8#include <linux/module.h>
   9#include <linux/mutex.h>
  10#include <linux/ftrace.h>
 
 
  11
  12#include "trace_output.h"
  13
  14/* must be a power of 2 */
  15#define EVENT_HASHSIZE	128
  16
  17DECLARE_RWSEM(trace_event_mutex);
  18
  19static struct hlist_head event_hash[EVENT_HASHSIZE] __read_mostly;
  20
  21static int next_event_type = __TRACE_LAST_TYPE + 1;
  22
  23int trace_print_seq(struct seq_file *m, struct trace_seq *s)
  24{
  25	int len = s->len >= PAGE_SIZE ? PAGE_SIZE - 1 : s->len;
  26	int ret;
 
  27
  28	ret = seq_write(m, s->buffer, len);
  29
  30	/*
  31	 * Only reset this buffer if we successfully wrote to the
  32	 * seq_file buffer.
  33	 */
  34	if (!ret)
  35		trace_seq_init(s);
  36
  37	return ret;
  38}
  39
  40enum print_line_t trace_print_bprintk_msg_only(struct trace_iterator *iter)
  41{
  42	struct trace_seq *s = &iter->seq;
  43	struct trace_entry *entry = iter->ent;
  44	struct bprint_entry *field;
  45	int ret;
  46
  47	trace_assign_type(field, entry);
  48
  49	ret = trace_seq_bprintf(s, field->fmt, field->buf);
  50	if (!ret)
  51		return TRACE_TYPE_PARTIAL_LINE;
  52
  53	return TRACE_TYPE_HANDLED;
  54}
  55
  56enum print_line_t trace_print_printk_msg_only(struct trace_iterator *iter)
  57{
  58	struct trace_seq *s = &iter->seq;
  59	struct trace_entry *entry = iter->ent;
  60	struct print_entry *field;
  61	int ret;
  62
  63	trace_assign_type(field, entry);
  64
  65	ret = trace_seq_printf(s, "%s", field->buf);
  66	if (!ret)
  67		return TRACE_TYPE_PARTIAL_LINE;
  68
  69	return TRACE_TYPE_HANDLED;
  70}
  71
  72/**
  73 * trace_seq_printf - sequence printing of trace information
  74 * @s: trace sequence descriptor
  75 * @fmt: printf format string
  76 *
  77 * It returns 0 if the trace oversizes the buffer's free
  78 * space, 1 otherwise.
  79 *
  80 * The tracer may use either sequence operations or its own
  81 * copy to user routines. To simplify formating of a trace
  82 * trace_seq_printf is used to store strings into a special
  83 * buffer (@s). Then the output may be either used by
  84 * the sequencer or pulled into another buffer.
  85 */
  86int
  87trace_seq_printf(struct trace_seq *s, const char *fmt, ...)
  88{
  89	int len = (PAGE_SIZE - 1) - s->len;
  90	va_list ap;
  91	int ret;
 
  92
  93	if (s->full || !len)
  94		return 0;
  95
  96	va_start(ap, fmt);
  97	ret = vsnprintf(s->buffer + s->len, len, fmt, ap);
  98	va_end(ap);
  99
 100	/* If we can't write it all, don't bother writing anything */
 101	if (ret >= len) {
 102		s->full = 1;
 103		return 0;
 
 
 
 104	}
 105
 106	s->len += ret;
 107
 108	return 1;
 109}
 110EXPORT_SYMBOL_GPL(trace_seq_printf);
 111
 112/**
 113 * trace_seq_vprintf - sequence printing of trace information
 114 * @s: trace sequence descriptor
 115 * @fmt: printf format string
 116 *
 117 * The tracer may use either sequence operations or its own
 118 * copy to user routines. To simplify formating of a trace
 119 * trace_seq_printf is used to store strings into a special
 120 * buffer (@s). Then the output may be either used by
 121 * the sequencer or pulled into another buffer.
 122 */
 123int
 124trace_seq_vprintf(struct trace_seq *s, const char *fmt, va_list args)
 125{
 126	int len = (PAGE_SIZE - 1) - s->len;
 127	int ret;
 128
 129	if (s->full || !len)
 130		return 0;
 131
 132	ret = vsnprintf(s->buffer + s->len, len, fmt, args);
 133
 134	/* If we can't write it all, don't bother writing anything */
 135	if (ret >= len) {
 136		s->full = 1;
 137		return 0;
 138	}
 139
 140	s->len += ret;
 141
 142	return len;
 143}
 144EXPORT_SYMBOL_GPL(trace_seq_vprintf);
 145
 146int trace_seq_bprintf(struct trace_seq *s, const char *fmt, const u32 *binary)
 
 
 147{
 148	int len = (PAGE_SIZE - 1) - s->len;
 149	int ret;
 150
 151	if (s->full || !len)
 152		return 0;
 153
 154	ret = bstr_printf(s->buffer + s->len, len, fmt, binary);
 
 155
 156	/* If we can't write it all, don't bother writing anything */
 157	if (ret >= len) {
 158		s->full = 1;
 159		return 0;
 160	}
 161
 162	s->len += ret;
 
 163
 164	return len;
 165}
 166
 167/**
 168 * trace_seq_puts - trace sequence printing of simple string
 169 * @s: trace sequence descriptor
 170 * @str: simple string to record
 171 *
 172 * The tracer may use either the sequence operations or its own
 173 * copy to user routines. This function records a simple string
 174 * into a special buffer (@s) for later retrieval by a sequencer
 175 * or other mechanism.
 176 */
 177int trace_seq_puts(struct trace_seq *s, const char *str)
 178{
 179	int len = strlen(str);
 180
 181	if (s->full)
 182		return 0;
 183
 184	if (len > ((PAGE_SIZE - 1) - s->len)) {
 185		s->full = 1;
 186		return 0;
 187	}
 188
 189	memcpy(s->buffer + s->len, str, len);
 190	s->len += len;
 191
 192	return len;
 193}
 194
 195int trace_seq_putc(struct trace_seq *s, unsigned char c)
 196{
 197	if (s->full)
 198		return 0;
 199
 200	if (s->len >= (PAGE_SIZE - 1)) {
 201		s->full = 1;
 202		return 0;
 203	}
 204
 205	s->buffer[s->len++] = c;
 206
 207	return 1;
 208}
 209EXPORT_SYMBOL(trace_seq_putc);
 210
 211int trace_seq_putmem(struct trace_seq *s, const void *mem, size_t len)
 212{
 213	if (s->full)
 214		return 0;
 215
 216	if (len > ((PAGE_SIZE - 1) - s->len)) {
 217		s->full = 1;
 218		return 0;
 219	}
 220
 221	memcpy(s->buffer + s->len, mem, len);
 222	s->len += len;
 223
 224	return len;
 225}
 226
 227int trace_seq_putmem_hex(struct trace_seq *s, const void *mem, size_t len)
 228{
 229	unsigned char hex[HEX_CHARS];
 230	const unsigned char *data = mem;
 231	int i, j;
 232
 233	if (s->full)
 234		return 0;
 235
 236#ifdef __BIG_ENDIAN
 237	for (i = 0, j = 0; i < len; i++) {
 238#else
 239	for (i = len-1, j = 0; i >= 0; i--) {
 240#endif
 241		hex[j++] = hex_asc_hi(data[i]);
 242		hex[j++] = hex_asc_lo(data[i]);
 243	}
 244	hex[j++] = ' ';
 245
 246	return trace_seq_putmem(s, hex, j);
 247}
 248
 249void *trace_seq_reserve(struct trace_seq *s, size_t len)
 250{
 251	void *ret;
 252
 253	if (s->full)
 254		return NULL;
 255
 256	if (len > ((PAGE_SIZE - 1) - s->len)) {
 257		s->full = 1;
 258		return NULL;
 259	}
 260
 261	ret = s->buffer + s->len;
 262	s->len += len;
 263
 264	return ret;
 265}
 
 266
 267int trace_seq_path(struct trace_seq *s, struct path *path)
 268{
 269	unsigned char *p;
 270
 271	if (s->full)
 272		return 0;
 273
 274	if (s->len >= (PAGE_SIZE - 1)) {
 275		s->full = 1;
 276		return 0;
 277	}
 278
 279	p = d_path(path, s->buffer + s->len, PAGE_SIZE - s->len);
 280	if (!IS_ERR(p)) {
 281		p = mangle_path(s->buffer + s->len, p, "\n");
 282		if (p) {
 283			s->len = p - s->buffer;
 284			return 1;
 285		}
 286	} else {
 287		s->buffer[s->len++] = '?';
 288		return 1;
 289	}
 290
 291	s->full = 1;
 292	return 0;
 293}
 294
 295const char *
 296ftrace_print_flags_seq(struct trace_seq *p, const char *delim,
 297		       unsigned long flags,
 298		       const struct trace_print_flags *flag_array)
 299{
 300	unsigned long mask;
 301	const char *str;
 302	const char *ret = p->buffer + p->len;
 303	int i;
 304
 305	for (i = 0;  flag_array[i].name && flags; i++) {
 306
 307		mask = flag_array[i].mask;
 308		if ((flags & mask) != mask)
 309			continue;
 310
 311		str = flag_array[i].name;
 312		flags &= ~mask;
 313		if (p->len && delim)
 314			trace_seq_puts(p, delim);
 
 
 315		trace_seq_puts(p, str);
 316	}
 317
 318	/* check for left over flags */
 319	if (flags) {
 320		if (p->len && delim)
 321			trace_seq_puts(p, delim);
 322		trace_seq_printf(p, "0x%lx", flags);
 323	}
 324
 325	trace_seq_putc(p, 0);
 326
 327	return ret;
 328}
 329EXPORT_SYMBOL(ftrace_print_flags_seq);
 330
 331const char *
 332ftrace_print_symbols_seq(struct trace_seq *p, unsigned long val,
 333			 const struct trace_print_flags *symbol_array)
 334{
 335	int i;
 336	const char *ret = p->buffer + p->len;
 337
 338	for (i = 0;  symbol_array[i].name; i++) {
 339
 340		if (val != symbol_array[i].mask)
 341			continue;
 342
 343		trace_seq_puts(p, symbol_array[i].name);
 344		break;
 345	}
 346
 347	if (!p->len)
 348		trace_seq_printf(p, "0x%lx", val);
 349		
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 350	trace_seq_putc(p, 0);
 351
 352	return ret;
 353}
 354EXPORT_SYMBOL(ftrace_print_symbols_seq);
 355
 356#if BITS_PER_LONG == 32
 
 
 
 
 
 
 
 
 
 
 357const char *
 358ftrace_print_symbols_seq_u64(struct trace_seq *p, unsigned long long val,
 359			 const struct trace_print_flags_u64 *symbol_array)
 360{
 361	int i;
 362	const char *ret = p->buffer + p->len;
 363
 364	for (i = 0;  symbol_array[i].name; i++) {
 
 
 
 365
 366		if (val != symbol_array[i].mask)
 367			continue;
 
 368
 369		trace_seq_puts(p, symbol_array[i].name);
 370		break;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 371	}
 372
 373	if (!p->len)
 374		trace_seq_printf(p, "0x%llx", val);
 375
 376	trace_seq_putc(p, 0);
 377
 378	return ret;
 379}
 380EXPORT_SYMBOL(ftrace_print_symbols_seq_u64);
 381#endif
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 382
 383const char *
 384ftrace_print_hex_seq(struct trace_seq *p, const unsigned char *buf, int buf_len)
 385{
 386	int i;
 387	const char *ret = p->buffer + p->len;
 
 
 
 
 
 388
 389	for (i = 0; i < buf_len; i++)
 390		trace_seq_printf(p, "%s%2.2x", i == 0 ? "" : " ", buf[i]);
 
 
 391
 392	trace_seq_putc(p, 0);
 
 
 393
 394	return ret;
 395}
 396EXPORT_SYMBOL(ftrace_print_hex_seq);
 397
 398#ifdef CONFIG_KRETPROBES
 399static inline const char *kretprobed(const char *name)
 400{
 401	static const char tramp_name[] = "kretprobe_trampoline";
 402	int size = sizeof(tramp_name);
 403
 404	if (strncmp(tramp_name, name, size) == 0)
 405		return "[unknown/kretprobe'd]";
 406	return name;
 407}
 408#else
 409static inline const char *kretprobed(const char *name)
 410{
 411	return name;
 412}
 413#endif /* CONFIG_KRETPROBES */
 414
 415static int
 416seq_print_sym_short(struct trace_seq *s, const char *fmt, unsigned long address)
 417{
 
 418#ifdef CONFIG_KALLSYMS
 419	char str[KSYM_SYMBOL_LEN];
 420	const char *name;
 421
 422	kallsyms_lookup(address, NULL, NULL, NULL, str);
 423
 424	name = kretprobed(str);
 425
 426	return trace_seq_printf(s, fmt, name);
 
 
 
 427#endif
 428	return 1;
 
 429}
 430
 431static int
 432seq_print_sym_offset(struct trace_seq *s, const char *fmt,
 433		     unsigned long address)
 434{
 
 435#ifdef CONFIG_KALLSYMS
 436	char str[KSYM_SYMBOL_LEN];
 437	const char *name;
 438
 439	sprint_symbol(str, address);
 440	name = kretprobed(str);
 441
 442	return trace_seq_printf(s, fmt, name);
 
 
 
 443#endif
 444	return 1;
 
 445}
 446
 447#ifndef CONFIG_64BIT
 448# define IP_FMT "%08lx"
 449#else
 450# define IP_FMT "%016lx"
 451#endif
 452
 453int seq_print_user_ip(struct trace_seq *s, struct mm_struct *mm,
 454		      unsigned long ip, unsigned long sym_flags)
 455{
 456	struct file *file = NULL;
 457	unsigned long vmstart = 0;
 458	int ret = 1;
 459
 460	if (s->full)
 461		return 0;
 462
 463	if (mm) {
 464		const struct vm_area_struct *vma;
 465
 466		down_read(&mm->mmap_sem);
 467		vma = find_vma(mm, ip);
 468		if (vma) {
 469			file = vma->vm_file;
 470			vmstart = vma->vm_start;
 471		}
 472		if (file) {
 473			ret = trace_seq_path(s, &file->f_path);
 474			if (ret)
 475				ret = trace_seq_printf(s, "[+0x%lx]",
 476						       ip - vmstart);
 477		}
 478		up_read(&mm->mmap_sem);
 479	}
 480	if (ret && ((sym_flags & TRACE_ITER_SYM_ADDR) || !file))
 481		ret = trace_seq_printf(s, " <" IP_FMT ">", ip);
 482	return ret;
 483}
 484
 485int
 486seq_print_userip_objs(const struct userstack_entry *entry, struct trace_seq *s,
 487		      unsigned long sym_flags)
 488{
 489	struct mm_struct *mm = NULL;
 490	int ret = 1;
 491	unsigned int i;
 492
 493	if (trace_flags & TRACE_ITER_SYM_USEROBJ) {
 494		struct task_struct *task;
 495		/*
 496		 * we do the lookup on the thread group leader,
 497		 * since individual threads might have already quit!
 498		 */
 499		rcu_read_lock();
 500		task = find_task_by_vpid(entry->tgid);
 501		if (task)
 502			mm = get_task_mm(task);
 503		rcu_read_unlock();
 504	}
 505
 506	for (i = 0; i < FTRACE_STACK_ENTRIES; i++) {
 507		unsigned long ip = entry->caller[i];
 508
 509		if (ip == ULONG_MAX || !ret)
 510			break;
 511		if (ret)
 512			ret = trace_seq_puts(s, " => ");
 513		if (!ip) {
 514			if (ret)
 515				ret = trace_seq_puts(s, "??");
 516			if (ret)
 517				ret = trace_seq_puts(s, "\n");
 518			continue;
 519		}
 520		if (!ret)
 521			break;
 522		if (ret)
 523			ret = seq_print_user_ip(s, mm, ip, sym_flags);
 524		ret = trace_seq_puts(s, "\n");
 525	}
 526
 527	if (mm)
 528		mmput(mm);
 529	return ret;
 530}
 531
 532int
 533seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags)
 534{
 535	int ret;
 536
 537	if (!ip)
 538		return trace_seq_printf(s, "0");
 539
 540	if (sym_flags & TRACE_ITER_SYM_OFFSET)
 541		ret = seq_print_sym_offset(s, "%s", ip);
 542	else
 543		ret = seq_print_sym_short(s, "%s", ip);
 544
 545	if (!ret)
 546		return 0;
 547
 548	if (sym_flags & TRACE_ITER_SYM_ADDR)
 549		ret = trace_seq_printf(s, " <" IP_FMT ">", ip);
 550	return ret;
 551}
 552
 553/**
 554 * trace_print_lat_fmt - print the irq, preempt and lockdep fields
 555 * @s: trace seq struct to write to
 556 * @entry: The trace entry field from the ring buffer
 557 *
 558 * Prints the generic fields of irqs off, in hard or softirq, preempt
 559 * count.
 560 */
 561int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
 562{
 563	char hardsoft_irq;
 564	char need_resched;
 565	char irqs_off;
 566	int hardirq;
 567	int softirq;
 568	int ret;
 569
 
 570	hardirq = entry->flags & TRACE_FLAG_HARDIRQ;
 571	softirq = entry->flags & TRACE_FLAG_SOFTIRQ;
 572
 573	irqs_off =
 574		(entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' :
 575		(entry->flags & TRACE_FLAG_IRQS_NOSUPPORT) ? 'X' :
 576		'.';
 577	need_resched =
 578		(entry->flags & TRACE_FLAG_NEED_RESCHED) ? 'N' : '.';
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 579	hardsoft_irq =
 
 
 580		(hardirq && softirq) ? 'H' :
 581		hardirq ? 'h' :
 582		softirq ? 's' :
 583		'.';
 584
 585	if (!trace_seq_printf(s, "%c%c%c",
 586			      irqs_off, need_resched, hardsoft_irq))
 587		return 0;
 588
 589	if (entry->preempt_count)
 590		ret = trace_seq_printf(s, "%x", entry->preempt_count);
 591	else
 592		ret = trace_seq_putc(s, '.');
 593
 594	return ret;
 595}
 596
 597static int
 598lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu)
 599{
 600	char comm[TASK_COMM_LEN];
 601
 602	trace_find_cmdline(entry->pid, comm);
 603
 604	if (!trace_seq_printf(s, "%8.8s-%-5d %3d",
 605			      comm, entry->pid, cpu))
 606		return 0;
 607
 608	return trace_print_lat_fmt(s, entry);
 609}
 610
 611static unsigned long preempt_mark_thresh = 100;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 612
 613static int
 614lat_print_timestamp(struct trace_seq *s, u64 abs_usecs,
 615		    unsigned long rel_usecs)
 616{
 617	return trace_seq_printf(s, " %4lldus%c: ", abs_usecs,
 618				rel_usecs > preempt_mark_thresh ? '!' :
 619				  rel_usecs > 1 ? '+' : ' ');
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 620}
 621
 622int trace_print_context(struct trace_iterator *iter)
 623{
 
 624	struct trace_seq *s = &iter->seq;
 625	struct trace_entry *entry = iter->ent;
 626	unsigned long long t = ns2usecs(iter->ts);
 627	unsigned long usec_rem = do_div(t, USEC_PER_SEC);
 628	unsigned long secs = (unsigned long)t;
 629	char comm[TASK_COMM_LEN];
 630
 631	trace_find_cmdline(entry->pid, comm);
 632
 633	return trace_seq_printf(s, "%16s-%-5d [%03d] %5lu.%06lu: ",
 634				comm, entry->pid, iter->cpu, secs, usec_rem);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 635}
 636
 637int trace_print_lat_context(struct trace_iterator *iter)
 638{
 
 
 
 
 639	u64 next_ts;
 640	int ret;
 641	struct trace_seq *s = &iter->seq;
 642	struct trace_entry *entry = iter->ent,
 643			   *next_entry = trace_find_next_entry(iter, NULL,
 644							       &next_ts);
 645	unsigned long verbose = (trace_flags & TRACE_ITER_VERBOSE);
 646	unsigned long abs_usecs = ns2usecs(iter->ts - iter->tr->time_start);
 647	unsigned long rel_usecs;
 
 648
 649	if (!next_entry)
 650		next_ts = iter->ts;
 651	rel_usecs = ns2usecs(next_ts - iter->ts);
 652
 653	if (verbose) {
 654		char comm[TASK_COMM_LEN];
 655
 656		trace_find_cmdline(entry->pid, comm);
 657
 658		ret = trace_seq_printf(s, "%16s %5d %3d %d %08x %08lx [%08llx]"
 659				       " %ld.%03ldms (+%ld.%03ldms): ", comm,
 660				       entry->pid, iter->cpu, entry->flags,
 661				       entry->preempt_count, iter->idx,
 662				       ns2usecs(iter->ts),
 663				       abs_usecs / USEC_PER_MSEC,
 664				       abs_usecs % USEC_PER_MSEC,
 665				       rel_usecs / USEC_PER_MSEC,
 666				       rel_usecs % USEC_PER_MSEC);
 667	} else {
 668		ret = lat_print_generic(s, entry, iter->cpu);
 669		if (ret)
 670			ret = lat_print_timestamp(s, abs_usecs, rel_usecs);
 671	}
 672
 673	return ret;
 674}
 675
 676static const char state_to_char[] = TASK_STATE_TO_CHAR_STR;
 677
 678static int task_state_char(unsigned long state)
 679{
 680	int bit = state ? __ffs(state) + 1 : 0;
 681
 682	return bit < sizeof(state_to_char) - 1 ? state_to_char[bit] : '?';
 683}
 684
 685/**
 686 * ftrace_find_event - find a registered event
 687 * @type: the type of event to look for
 688 *
 689 * Returns an event of type @type otherwise NULL
 690 * Called with trace_event_read_lock() held.
 691 */
 692struct trace_event *ftrace_find_event(int type)
 693{
 694	struct trace_event *event;
 695	struct hlist_node *n;
 696	unsigned key;
 697
 698	key = type & (EVENT_HASHSIZE - 1);
 699
 700	hlist_for_each_entry(event, n, &event_hash[key], node) {
 701		if (event->type == type)
 702			return event;
 703	}
 704
 705	return NULL;
 706}
 707
 708static LIST_HEAD(ftrace_event_list);
 709
 710static int trace_search_list(struct list_head **list)
 711{
 712	struct trace_event *e;
 713	int last = __TRACE_LAST_TYPE;
 714
 715	if (list_empty(&ftrace_event_list)) {
 716		*list = &ftrace_event_list;
 717		return last + 1;
 718	}
 719
 720	/*
 721	 * We used up all possible max events,
 722	 * lets see if somebody freed one.
 723	 */
 724	list_for_each_entry(e, &ftrace_event_list, list) {
 725		if (e->type != last + 1)
 726			break;
 727		last++;
 728	}
 729
 730	/* Did we used up all 65 thousand events??? */
 731	if ((last + 1) > FTRACE_MAX_EVENT)
 732		return 0;
 733
 734	*list = &e->list;
 735	return last + 1;
 736}
 737
 738void trace_event_read_lock(void)
 739{
 740	down_read(&trace_event_mutex);
 741}
 742
 743void trace_event_read_unlock(void)
 744{
 745	up_read(&trace_event_mutex);
 746}
 747
 748/**
 749 * register_ftrace_event - register output for an event type
 750 * @event: the event type to register
 751 *
 752 * Event types are stored in a hash and this hash is used to
 753 * find a way to print an event. If the @event->type is set
 754 * then it will use that type, otherwise it will assign a
 755 * type to use.
 756 *
 757 * If you assign your own type, please make sure it is added
 758 * to the trace_type enum in trace.h, to avoid collisions
 759 * with the dynamic types.
 760 *
 761 * Returns the event type number or zero on error.
 762 */
 763int register_ftrace_event(struct trace_event *event)
 764{
 765	unsigned key;
 766	int ret = 0;
 767
 768	down_write(&trace_event_mutex);
 769
 770	if (WARN_ON(!event))
 771		goto out;
 772
 773	if (WARN_ON(!event->funcs))
 774		goto out;
 775
 776	INIT_LIST_HEAD(&event->list);
 777
 778	if (!event->type) {
 779		struct list_head *list = NULL;
 780
 781		if (next_event_type > FTRACE_MAX_EVENT) {
 782
 783			event->type = trace_search_list(&list);
 784			if (!event->type)
 785				goto out;
 786
 787		} else {
 788			
 789			event->type = next_event_type++;
 790			list = &ftrace_event_list;
 791		}
 792
 793		if (WARN_ON(ftrace_find_event(event->type)))
 794			goto out;
 795
 796		list_add_tail(&event->list, list);
 797
 798	} else if (event->type > __TRACE_LAST_TYPE) {
 799		printk(KERN_WARNING "Need to add type to trace.h\n");
 800		WARN_ON(1);
 801		goto out;
 802	} else {
 803		/* Is this event already used */
 804		if (ftrace_find_event(event->type))
 805			goto out;
 806	}
 807
 808	if (event->funcs->trace == NULL)
 809		event->funcs->trace = trace_nop_print;
 810	if (event->funcs->raw == NULL)
 811		event->funcs->raw = trace_nop_print;
 812	if (event->funcs->hex == NULL)
 813		event->funcs->hex = trace_nop_print;
 814	if (event->funcs->binary == NULL)
 815		event->funcs->binary = trace_nop_print;
 816
 817	key = event->type & (EVENT_HASHSIZE - 1);
 818
 819	hlist_add_head(&event->node, &event_hash[key]);
 820
 821	ret = event->type;
 822 out:
 823	up_write(&trace_event_mutex);
 824
 825	return ret;
 826}
 827EXPORT_SYMBOL_GPL(register_ftrace_event);
 828
 829/*
 830 * Used by module code with the trace_event_mutex held for write.
 831 */
 832int __unregister_ftrace_event(struct trace_event *event)
 833{
 834	hlist_del(&event->node);
 835	list_del(&event->list);
 836	return 0;
 837}
 838
 839/**
 840 * unregister_ftrace_event - remove a no longer used event
 841 * @event: the event to remove
 842 */
 843int unregister_ftrace_event(struct trace_event *event)
 844{
 845	down_write(&trace_event_mutex);
 846	__unregister_ftrace_event(event);
 847	up_write(&trace_event_mutex);
 848
 849	return 0;
 850}
 851EXPORT_SYMBOL_GPL(unregister_ftrace_event);
 852
 853/*
 854 * Standard events
 855 */
 856
 857enum print_line_t trace_nop_print(struct trace_iterator *iter, int flags,
 858				  struct trace_event *event)
 859{
 860	if (!trace_seq_printf(&iter->seq, "type: %d\n", iter->ent->type))
 861		return TRACE_TYPE_PARTIAL_LINE;
 862
 863	return TRACE_TYPE_HANDLED;
 864}
 865
 866/* TRACE_FN */
 867static enum print_line_t trace_fn_trace(struct trace_iterator *iter, int flags,
 868					struct trace_event *event)
 869{
 870	struct ftrace_entry *field;
 871	struct trace_seq *s = &iter->seq;
 872
 873	trace_assign_type(field, iter->ent);
 874
 875	if (!seq_print_ip_sym(s, field->ip, flags))
 876		goto partial;
 877
 878	if ((flags & TRACE_ITER_PRINT_PARENT) && field->parent_ip) {
 879		if (!trace_seq_printf(s, " <-"))
 880			goto partial;
 881		if (!seq_print_ip_sym(s,
 882				      field->parent_ip,
 883				      flags))
 884			goto partial;
 885	}
 886	if (!trace_seq_printf(s, "\n"))
 887		goto partial;
 888
 889	return TRACE_TYPE_HANDLED;
 890
 891 partial:
 892	return TRACE_TYPE_PARTIAL_LINE;
 893}
 894
 895static enum print_line_t trace_fn_raw(struct trace_iterator *iter, int flags,
 896				      struct trace_event *event)
 897{
 898	struct ftrace_entry *field;
 899
 900	trace_assign_type(field, iter->ent);
 901
 902	if (!trace_seq_printf(&iter->seq, "%lx %lx\n",
 903			      field->ip,
 904			      field->parent_ip))
 905		return TRACE_TYPE_PARTIAL_LINE;
 906
 907	return TRACE_TYPE_HANDLED;
 908}
 909
 910static enum print_line_t trace_fn_hex(struct trace_iterator *iter, int flags,
 911				      struct trace_event *event)
 912{
 913	struct ftrace_entry *field;
 914	struct trace_seq *s = &iter->seq;
 915
 916	trace_assign_type(field, iter->ent);
 917
 918	SEQ_PUT_HEX_FIELD_RET(s, field->ip);
 919	SEQ_PUT_HEX_FIELD_RET(s, field->parent_ip);
 920
 921	return TRACE_TYPE_HANDLED;
 922}
 923
 924static enum print_line_t trace_fn_bin(struct trace_iterator *iter, int flags,
 925				      struct trace_event *event)
 926{
 927	struct ftrace_entry *field;
 928	struct trace_seq *s = &iter->seq;
 929
 930	trace_assign_type(field, iter->ent);
 931
 932	SEQ_PUT_FIELD_RET(s, field->ip);
 933	SEQ_PUT_FIELD_RET(s, field->parent_ip);
 934
 935	return TRACE_TYPE_HANDLED;
 936}
 937
 938static struct trace_event_functions trace_fn_funcs = {
 939	.trace		= trace_fn_trace,
 940	.raw		= trace_fn_raw,
 941	.hex		= trace_fn_hex,
 942	.binary		= trace_fn_bin,
 943};
 944
 945static struct trace_event trace_fn_event = {
 946	.type		= TRACE_FN,
 947	.funcs		= &trace_fn_funcs,
 948};
 949
 950/* TRACE_CTX an TRACE_WAKE */
 951static enum print_line_t trace_ctxwake_print(struct trace_iterator *iter,
 952					     char *delim)
 953{
 954	struct ctx_switch_entry *field;
 955	char comm[TASK_COMM_LEN];
 956	int S, T;
 957
 958
 959	trace_assign_type(field, iter->ent);
 960
 961	T = task_state_char(field->next_state);
 962	S = task_state_char(field->prev_state);
 963	trace_find_cmdline(field->next_pid, comm);
 964	if (!trace_seq_printf(&iter->seq,
 965			      " %5d:%3d:%c %s [%03d] %5d:%3d:%c %s\n",
 966			      field->prev_pid,
 967			      field->prev_prio,
 968			      S, delim,
 969			      field->next_cpu,
 970			      field->next_pid,
 971			      field->next_prio,
 972			      T, comm))
 973		return TRACE_TYPE_PARTIAL_LINE;
 974
 975	return TRACE_TYPE_HANDLED;
 976}
 977
 978static enum print_line_t trace_ctx_print(struct trace_iterator *iter, int flags,
 979					 struct trace_event *event)
 980{
 981	return trace_ctxwake_print(iter, "==>");
 982}
 983
 984static enum print_line_t trace_wake_print(struct trace_iterator *iter,
 985					  int flags, struct trace_event *event)
 986{
 987	return trace_ctxwake_print(iter, "  +");
 988}
 989
 990static int trace_ctxwake_raw(struct trace_iterator *iter, char S)
 991{
 992	struct ctx_switch_entry *field;
 993	int T;
 994
 995	trace_assign_type(field, iter->ent);
 996
 997	if (!S)
 998		S = task_state_char(field->prev_state);
 999	T = task_state_char(field->next_state);
1000	if (!trace_seq_printf(&iter->seq, "%d %d %c %d %d %d %c\n",
1001			      field->prev_pid,
1002			      field->prev_prio,
1003			      S,
1004			      field->next_cpu,
1005			      field->next_pid,
1006			      field->next_prio,
1007			      T))
1008		return TRACE_TYPE_PARTIAL_LINE;
1009
1010	return TRACE_TYPE_HANDLED;
1011}
1012
1013static enum print_line_t trace_ctx_raw(struct trace_iterator *iter, int flags,
1014				       struct trace_event *event)
1015{
1016	return trace_ctxwake_raw(iter, 0);
1017}
1018
1019static enum print_line_t trace_wake_raw(struct trace_iterator *iter, int flags,
1020					struct trace_event *event)
1021{
1022	return trace_ctxwake_raw(iter, '+');
1023}
1024
1025
1026static int trace_ctxwake_hex(struct trace_iterator *iter, char S)
1027{
1028	struct ctx_switch_entry *field;
1029	struct trace_seq *s = &iter->seq;
1030	int T;
1031
1032	trace_assign_type(field, iter->ent);
1033
1034	if (!S)
1035		S = task_state_char(field->prev_state);
1036	T = task_state_char(field->next_state);
1037
1038	SEQ_PUT_HEX_FIELD_RET(s, field->prev_pid);
1039	SEQ_PUT_HEX_FIELD_RET(s, field->prev_prio);
1040	SEQ_PUT_HEX_FIELD_RET(s, S);
1041	SEQ_PUT_HEX_FIELD_RET(s, field->next_cpu);
1042	SEQ_PUT_HEX_FIELD_RET(s, field->next_pid);
1043	SEQ_PUT_HEX_FIELD_RET(s, field->next_prio);
1044	SEQ_PUT_HEX_FIELD_RET(s, T);
1045
1046	return TRACE_TYPE_HANDLED;
1047}
1048
1049static enum print_line_t trace_ctx_hex(struct trace_iterator *iter, int flags,
1050				       struct trace_event *event)
1051{
1052	return trace_ctxwake_hex(iter, 0);
1053}
1054
1055static enum print_line_t trace_wake_hex(struct trace_iterator *iter, int flags,
1056					struct trace_event *event)
1057{
1058	return trace_ctxwake_hex(iter, '+');
1059}
1060
1061static enum print_line_t trace_ctxwake_bin(struct trace_iterator *iter,
1062					   int flags, struct trace_event *event)
1063{
1064	struct ctx_switch_entry *field;
1065	struct trace_seq *s = &iter->seq;
1066
1067	trace_assign_type(field, iter->ent);
1068
1069	SEQ_PUT_FIELD_RET(s, field->prev_pid);
1070	SEQ_PUT_FIELD_RET(s, field->prev_prio);
1071	SEQ_PUT_FIELD_RET(s, field->prev_state);
1072	SEQ_PUT_FIELD_RET(s, field->next_pid);
1073	SEQ_PUT_FIELD_RET(s, field->next_prio);
1074	SEQ_PUT_FIELD_RET(s, field->next_state);
 
1075
1076	return TRACE_TYPE_HANDLED;
1077}
1078
1079static struct trace_event_functions trace_ctx_funcs = {
1080	.trace		= trace_ctx_print,
1081	.raw		= trace_ctx_raw,
1082	.hex		= trace_ctx_hex,
1083	.binary		= trace_ctxwake_bin,
1084};
1085
1086static struct trace_event trace_ctx_event = {
1087	.type		= TRACE_CTX,
1088	.funcs		= &trace_ctx_funcs,
1089};
1090
1091static struct trace_event_functions trace_wake_funcs = {
1092	.trace		= trace_wake_print,
1093	.raw		= trace_wake_raw,
1094	.hex		= trace_wake_hex,
1095	.binary		= trace_ctxwake_bin,
1096};
1097
1098static struct trace_event trace_wake_event = {
1099	.type		= TRACE_WAKE,
1100	.funcs		= &trace_wake_funcs,
1101};
1102
1103/* TRACE_STACK */
1104
1105static enum print_line_t trace_stack_print(struct trace_iterator *iter,
1106					   int flags, struct trace_event *event)
1107{
1108	struct stack_entry *field;
1109	struct trace_seq *s = &iter->seq;
1110	unsigned long *p;
1111	unsigned long *end;
1112
1113	trace_assign_type(field, iter->ent);
1114	end = (unsigned long *)((long)iter->ent + iter->ent_size);
1115
1116	if (!trace_seq_puts(s, "<stack trace>\n"))
1117		goto partial;
1118
1119	for (p = field->caller; p && *p != ULONG_MAX && p < end; p++) {
1120		if (!trace_seq_puts(s, " => "))
1121			goto partial;
1122
1123		if (!seq_print_ip_sym(s, *p, flags))
1124			goto partial;
1125		if (!trace_seq_puts(s, "\n"))
1126			goto partial;
 
 
1127	}
1128
1129	return TRACE_TYPE_HANDLED;
1130
1131 partial:
1132	return TRACE_TYPE_PARTIAL_LINE;
1133}
1134
1135static struct trace_event_functions trace_stack_funcs = {
1136	.trace		= trace_stack_print,
1137};
1138
1139static struct trace_event trace_stack_event = {
1140	.type		= TRACE_STACK,
1141	.funcs		= &trace_stack_funcs,
1142};
1143
1144/* TRACE_USER_STACK */
1145static enum print_line_t trace_user_stack_print(struct trace_iterator *iter,
1146						int flags, struct trace_event *event)
1147{
 
1148	struct userstack_entry *field;
1149	struct trace_seq *s = &iter->seq;
 
 
1150
1151	trace_assign_type(field, iter->ent);
1152
1153	if (!trace_seq_puts(s, "<user stack trace>\n"))
1154		goto partial;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1155
1156	if (!seq_print_userip_objs(field, s, flags))
1157		goto partial;
1158
1159	return TRACE_TYPE_HANDLED;
1160
1161 partial:
1162	return TRACE_TYPE_PARTIAL_LINE;
 
 
 
 
 
 
 
 
 
 
 
 
1163}
1164
1165static struct trace_event_functions trace_user_stack_funcs = {
1166	.trace		= trace_user_stack_print,
1167};
1168
1169static struct trace_event trace_user_stack_event = {
1170	.type		= TRACE_USER_STACK,
1171	.funcs		= &trace_user_stack_funcs,
1172};
1173
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1174/* TRACE_BPRINT */
1175static enum print_line_t
1176trace_bprint_print(struct trace_iterator *iter, int flags,
1177		   struct trace_event *event)
1178{
1179	struct trace_entry *entry = iter->ent;
1180	struct trace_seq *s = &iter->seq;
1181	struct bprint_entry *field;
1182
1183	trace_assign_type(field, entry);
1184
1185	if (!seq_print_ip_sym(s, field->ip, flags))
1186		goto partial;
1187
1188	if (!trace_seq_puts(s, ": "))
1189		goto partial;
1190
1191	if (!trace_seq_bprintf(s, field->fmt, field->buf))
1192		goto partial;
1193
1194	return TRACE_TYPE_HANDLED;
1195
1196 partial:
1197	return TRACE_TYPE_PARTIAL_LINE;
1198}
1199
1200
1201static enum print_line_t
1202trace_bprint_raw(struct trace_iterator *iter, int flags,
1203		 struct trace_event *event)
1204{
1205	struct bprint_entry *field;
1206	struct trace_seq *s = &iter->seq;
1207
1208	trace_assign_type(field, iter->ent);
1209
1210	if (!trace_seq_printf(s, ": %lx : ", field->ip))
1211		goto partial;
1212
1213	if (!trace_seq_bprintf(s, field->fmt, field->buf))
1214		goto partial;
1215
1216	return TRACE_TYPE_HANDLED;
1217
1218 partial:
1219	return TRACE_TYPE_PARTIAL_LINE;
1220}
1221
1222static struct trace_event_functions trace_bprint_funcs = {
1223	.trace		= trace_bprint_print,
1224	.raw		= trace_bprint_raw,
1225};
1226
1227static struct trace_event trace_bprint_event = {
1228	.type		= TRACE_BPRINT,
1229	.funcs		= &trace_bprint_funcs,
1230};
1231
1232/* TRACE_PRINT */
1233static enum print_line_t trace_print_print(struct trace_iterator *iter,
1234					   int flags, struct trace_event *event)
1235{
1236	struct print_entry *field;
1237	struct trace_seq *s = &iter->seq;
1238
1239	trace_assign_type(field, iter->ent);
1240
1241	if (!seq_print_ip_sym(s, field->ip, flags))
1242		goto partial;
1243
1244	if (!trace_seq_printf(s, ": %s", field->buf))
1245		goto partial;
1246
1247	return TRACE_TYPE_HANDLED;
1248
1249 partial:
1250	return TRACE_TYPE_PARTIAL_LINE;
1251}
1252
1253static enum print_line_t trace_print_raw(struct trace_iterator *iter, int flags,
1254					 struct trace_event *event)
1255{
1256	struct print_entry *field;
1257
1258	trace_assign_type(field, iter->ent);
1259
1260	if (!trace_seq_printf(&iter->seq, "# %lx %s", field->ip, field->buf))
1261		goto partial;
1262
1263	return TRACE_TYPE_HANDLED;
1264
1265 partial:
1266	return TRACE_TYPE_PARTIAL_LINE;
1267}
1268
1269static struct trace_event_functions trace_print_funcs = {
1270	.trace		= trace_print_print,
1271	.raw		= trace_print_raw,
1272};
1273
1274static struct trace_event trace_print_event = {
1275	.type	 	= TRACE_PRINT,
1276	.funcs		= &trace_print_funcs,
1277};
1278
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1279
1280static struct trace_event *events[] __initdata = {
1281	&trace_fn_event,
1282	&trace_ctx_event,
1283	&trace_wake_event,
1284	&trace_stack_event,
1285	&trace_user_stack_event,
 
1286	&trace_bprint_event,
1287	&trace_print_event,
 
 
1288	NULL
1289};
1290
1291__init static int init_events(void)
1292{
1293	struct trace_event *event;
1294	int i, ret;
1295
1296	for (i = 0; events[i]; i++) {
1297		event = events[i];
1298
1299		ret = register_ftrace_event(event);
1300		if (!ret) {
1301			printk(KERN_WARNING "event %d failed to register\n",
1302			       event->type);
1303			WARN_ON_ONCE(1);
1304		}
1305	}
1306
1307	return 0;
1308}
1309device_initcall(init_events);