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   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_sem);
  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_bputs_msg_only(struct trace_iterator *iter)
  41{
  42	struct trace_seq *s = &iter->seq;
  43	struct trace_entry *entry = iter->ent;
  44	struct bputs_entry *field;
  45	int ret;
  46
  47	trace_assign_type(field, entry);
  48
  49	ret = trace_seq_puts(s, field->str);
  50	if (!ret)
  51		return TRACE_TYPE_PARTIAL_LINE;
  52
  53	return TRACE_TYPE_HANDLED;
  54}
  55
  56enum print_line_t trace_print_bprintk_msg_only(struct trace_iterator *iter)
  57{
  58	struct trace_seq *s = &iter->seq;
  59	struct trace_entry *entry = iter->ent;
  60	struct bprint_entry *field;
  61	int ret;
  62
  63	trace_assign_type(field, entry);
  64
  65	ret = trace_seq_bprintf(s, field->fmt, field->buf);
  66	if (!ret)
  67		return TRACE_TYPE_PARTIAL_LINE;
  68
  69	return TRACE_TYPE_HANDLED;
  70}
  71
  72enum print_line_t trace_print_printk_msg_only(struct trace_iterator *iter)
  73{
  74	struct trace_seq *s = &iter->seq;
  75	struct trace_entry *entry = iter->ent;
  76	struct print_entry *field;
  77	int ret;
  78
  79	trace_assign_type(field, entry);
  80
  81	ret = trace_seq_puts(s, field->buf);
  82	if (!ret)
  83		return TRACE_TYPE_PARTIAL_LINE;
  84
  85	return TRACE_TYPE_HANDLED;
  86}
  87
  88/**
  89 * trace_seq_printf - sequence printing of trace information
  90 * @s: trace sequence descriptor
  91 * @fmt: printf format string
  92 *
  93 * It returns 0 if the trace oversizes the buffer's free
  94 * space, 1 otherwise.
  95 *
  96 * The tracer may use either sequence operations or its own
  97 * copy to user routines. To simplify formating of a trace
  98 * trace_seq_printf is used to store strings into a special
  99 * buffer (@s). Then the output may be either used by
 100 * the sequencer or pulled into another buffer.
 101 */
 102int
 103trace_seq_printf(struct trace_seq *s, const char *fmt, ...)
 104{
 105	int len = (PAGE_SIZE - 1) - s->len;
 106	va_list ap;
 107	int ret;
 108
 109	if (s->full || !len)
 110		return 0;
 111
 112	va_start(ap, fmt);
 113	ret = vsnprintf(s->buffer + s->len, len, fmt, ap);
 114	va_end(ap);
 115
 116	/* If we can't write it all, don't bother writing anything */
 117	if (ret >= len) {
 118		s->full = 1;
 119		return 0;
 120	}
 121
 122	s->len += ret;
 123
 124	return 1;
 125}
 126EXPORT_SYMBOL_GPL(trace_seq_printf);
 127
 128/**
 129 * trace_seq_vprintf - sequence printing of trace information
 130 * @s: trace sequence descriptor
 131 * @fmt: printf format string
 132 *
 133 * The tracer may use either sequence operations or its own
 134 * copy to user routines. To simplify formating of a trace
 135 * trace_seq_printf is used to store strings into a special
 136 * buffer (@s). Then the output may be either used by
 137 * the sequencer or pulled into another buffer.
 138 */
 139int
 140trace_seq_vprintf(struct trace_seq *s, const char *fmt, va_list args)
 141{
 142	int len = (PAGE_SIZE - 1) - s->len;
 143	int ret;
 144
 145	if (s->full || !len)
 146		return 0;
 147
 148	ret = vsnprintf(s->buffer + s->len, len, fmt, args);
 149
 150	/* If we can't write it all, don't bother writing anything */
 151	if (ret >= len) {
 152		s->full = 1;
 153		return 0;
 154	}
 155
 156	s->len += ret;
 157
 158	return len;
 159}
 160EXPORT_SYMBOL_GPL(trace_seq_vprintf);
 161
 162int trace_seq_bprintf(struct trace_seq *s, const char *fmt, const u32 *binary)
 163{
 164	int len = (PAGE_SIZE - 1) - s->len;
 165	int ret;
 166
 167	if (s->full || !len)
 168		return 0;
 169
 170	ret = bstr_printf(s->buffer + s->len, len, fmt, binary);
 171
 172	/* If we can't write it all, don't bother writing anything */
 173	if (ret >= len) {
 174		s->full = 1;
 175		return 0;
 176	}
 177
 178	s->len += ret;
 179
 180	return len;
 181}
 182
 183/**
 184 * trace_seq_puts - trace sequence printing of simple string
 185 * @s: trace sequence descriptor
 186 * @str: simple string to record
 187 *
 188 * The tracer may use either the sequence operations or its own
 189 * copy to user routines. This function records a simple string
 190 * into a special buffer (@s) for later retrieval by a sequencer
 191 * or other mechanism.
 192 */
 193int trace_seq_puts(struct trace_seq *s, const char *str)
 194{
 195	int len = strlen(str);
 196
 197	if (s->full)
 198		return 0;
 
 199
 200	if (len > ((PAGE_SIZE - 1) - s->len)) {
 201		s->full = 1;
 202		return 0;
 
 
 
 
 203	}
 204
 205	memcpy(s->buffer + s->len, str, len);
 206	s->len += len;
 207
 208	return len;
 209}
 210
 211int trace_seq_putc(struct trace_seq *s, unsigned char c)
 212{
 213	if (s->full)
 214		return 0;
 215
 216	if (s->len >= (PAGE_SIZE - 1)) {
 217		s->full = 1;
 218		return 0;
 219	}
 220
 221	s->buffer[s->len++] = c;
 222
 223	return 1;
 224}
 225EXPORT_SYMBOL(trace_seq_putc);
 226
 227int trace_seq_putmem(struct trace_seq *s, const void *mem, size_t len)
 
 
 228{
 229	if (s->full)
 230		return 0;
 231
 232	if (len > ((PAGE_SIZE - 1) - s->len)) {
 233		s->full = 1;
 234		return 0;
 235	}
 236
 237	memcpy(s->buffer + s->len, mem, len);
 238	s->len += len;
 239
 240	return len;
 241}
 242
 243int trace_seq_putmem_hex(struct trace_seq *s, const void *mem, size_t len)
 244{
 245	unsigned char hex[HEX_CHARS];
 246	const unsigned char *data = mem;
 247	int i, j;
 248
 249	if (s->full)
 250		return 0;
 251
 252#ifdef __BIG_ENDIAN
 253	for (i = 0, j = 0; i < len; i++) {
 254#else
 255	for (i = len-1, j = 0; i >= 0; i--) {
 256#endif
 257		hex[j++] = hex_asc_hi(data[i]);
 258		hex[j++] = hex_asc_lo(data[i]);
 259	}
 260	hex[j++] = ' ';
 261
 262	return trace_seq_putmem(s, hex, j);
 263}
 264
 265void *trace_seq_reserve(struct trace_seq *s, size_t len)
 266{
 267	void *ret;
 268
 269	if (s->full)
 270		return NULL;
 271
 272	if (len > ((PAGE_SIZE - 1) - s->len)) {
 273		s->full = 1;
 274		return NULL;
 275	}
 276
 277	ret = s->buffer + s->len;
 278	s->len += len;
 279
 280	return ret;
 281}
 
 282
 283int trace_seq_path(struct trace_seq *s, const struct path *path)
 284{
 285	unsigned char *p;
 286
 287	if (s->full)
 288		return 0;
 289
 290	if (s->len >= (PAGE_SIZE - 1)) {
 291		s->full = 1;
 292		return 0;
 293	}
 294
 295	p = d_path(path, s->buffer + s->len, PAGE_SIZE - s->len);
 296	if (!IS_ERR(p)) {
 297		p = mangle_path(s->buffer + s->len, p, "\n");
 298		if (p) {
 299			s->len = p - s->buffer;
 300			return 1;
 301		}
 302	} else {
 303		s->buffer[s->len++] = '?';
 304		return 1;
 305	}
 306
 307	s->full = 1;
 308	return 0;
 309}
 310
 311const char *
 312ftrace_print_flags_seq(struct trace_seq *p, const char *delim,
 313		       unsigned long flags,
 314		       const struct trace_print_flags *flag_array)
 315{
 316	unsigned long mask;
 317	const char *str;
 318	const char *ret = p->buffer + p->len;
 319	int i, first = 1;
 320
 321	for (i = 0;  flag_array[i].name && flags; i++) {
 322
 323		mask = flag_array[i].mask;
 324		if ((flags & mask) != mask)
 325			continue;
 326
 327		str = flag_array[i].name;
 328		flags &= ~mask;
 329		if (!first && delim)
 330			trace_seq_puts(p, delim);
 331		else
 332			first = 0;
 333		trace_seq_puts(p, str);
 334	}
 335
 336	/* check for left over flags */
 337	if (flags) {
 338		if (!first && delim)
 339			trace_seq_puts(p, delim);
 340		trace_seq_printf(p, "0x%lx", flags);
 341	}
 342
 343	trace_seq_putc(p, 0);
 344
 345	return ret;
 346}
 347EXPORT_SYMBOL(ftrace_print_flags_seq);
 348
 349const char *
 350ftrace_print_symbols_seq(struct trace_seq *p, unsigned long val,
 351			 const struct trace_print_flags *symbol_array)
 352{
 353	int i;
 354	const char *ret = p->buffer + p->len;
 355
 356	for (i = 0;  symbol_array[i].name; i++) {
 357
 358		if (val != symbol_array[i].mask)
 359			continue;
 360
 361		trace_seq_puts(p, symbol_array[i].name);
 362		break;
 363	}
 364
 365	if (ret == (const char *)(p->buffer + p->len))
 366		trace_seq_printf(p, "0x%lx", val);
 367		
 368	trace_seq_putc(p, 0);
 369
 370	return ret;
 371}
 372EXPORT_SYMBOL(ftrace_print_symbols_seq);
 
 373
 374#if BITS_PER_LONG == 32
 375const char *
 376ftrace_print_symbols_seq_u64(struct trace_seq *p, unsigned long long val,
 377			 const struct trace_print_flags_u64 *symbol_array)
 378{
 379	int i;
 380	const char *ret = p->buffer + p->len;
 381
 382	for (i = 0;  symbol_array[i].name; i++) {
 383
 384		if (val != symbol_array[i].mask)
 385			continue;
 386
 387		trace_seq_puts(p, symbol_array[i].name);
 388		break;
 389	}
 390
 391	if (ret == (const char *)(p->buffer + p->len))
 392		trace_seq_printf(p, "0x%llx", val);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 393
 
 
 394	trace_seq_putc(p, 0);
 395
 396	return ret;
 397}
 398EXPORT_SYMBOL(ftrace_print_symbols_seq_u64);
 399#endif
 400
 401const char *
 402ftrace_print_hex_seq(struct trace_seq *p, const unsigned char *buf, int buf_len)
 
 403{
 404	int i;
 405	const char *ret = p->buffer + p->len;
 406
 407	for (i = 0; i < buf_len; i++)
 408		trace_seq_printf(p, "%s%2.2x", i == 0 ? "" : " ", buf[i]);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 409
 
 410	trace_seq_putc(p, 0);
 411
 412	return ret;
 413}
 414EXPORT_SYMBOL(ftrace_print_hex_seq);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 415
 416int ftrace_raw_output_prep(struct trace_iterator *iter,
 417			   struct trace_event *trace_event)
 418{
 419	struct ftrace_event_call *event;
 420	struct trace_seq *s = &iter->seq;
 421	struct trace_seq *p = &iter->tmp_seq;
 422	struct trace_entry *entry;
 423	int ret;
 424
 425	event = container_of(trace_event, struct ftrace_event_call, event);
 426	entry = iter->ent;
 427
 428	if (entry->type != event->event.type) {
 429		WARN_ON_ONCE(1);
 430		return TRACE_TYPE_UNHANDLED;
 431	}
 432
 433	trace_seq_init(p);
 434	ret = trace_seq_printf(s, "%s: ", ftrace_event_name(event));
 435	if (!ret)
 436		return TRACE_TYPE_PARTIAL_LINE;
 437
 438	return 0;
 439}
 440EXPORT_SYMBOL(ftrace_raw_output_prep);
 441
 442static int ftrace_output_raw(struct trace_iterator *iter, char *name,
 443			     char *fmt, va_list ap)
 444{
 445	struct trace_seq *s = &iter->seq;
 446	int ret;
 447
 448	ret = trace_seq_printf(s, "%s: ", name);
 449	if (!ret)
 450		return TRACE_TYPE_PARTIAL_LINE;
 451
 452	ret = trace_seq_vprintf(s, fmt, ap);
 453
 454	if (!ret)
 455		return TRACE_TYPE_PARTIAL_LINE;
 456
 457	return TRACE_TYPE_HANDLED;
 458}
 459
 460int ftrace_output_call(struct trace_iterator *iter, char *name, char *fmt, ...)
 461{
 462	va_list ap;
 463	int ret;
 464
 465	va_start(ap, fmt);
 466	ret = ftrace_output_raw(iter, name, fmt, ap);
 467	va_end(ap);
 468
 469	return ret;
 470}
 471EXPORT_SYMBOL_GPL(ftrace_output_call);
 472
 473#ifdef CONFIG_KRETPROBES
 474static inline const char *kretprobed(const char *name)
 475{
 476	static const char tramp_name[] = "kretprobe_trampoline";
 477	int size = sizeof(tramp_name);
 478
 479	if (strncmp(tramp_name, name, size) == 0)
 480		return "[unknown/kretprobe'd]";
 481	return name;
 482}
 483#else
 484static inline const char *kretprobed(const char *name)
 485{
 486	return name;
 487}
 488#endif /* CONFIG_KRETPROBES */
 489
 490static int
 491seq_print_sym_short(struct trace_seq *s, const char *fmt, unsigned long address)
 492{
 493#ifdef CONFIG_KALLSYMS
 494	char str[KSYM_SYMBOL_LEN];
 495	const char *name;
 496
 497	kallsyms_lookup(address, NULL, NULL, NULL, str);
 498
 499	name = kretprobed(str);
 500
 501	return trace_seq_printf(s, fmt, name);
 502#endif
 503	return 1;
 504}
 505
 506static int
 507seq_print_sym_offset(struct trace_seq *s, const char *fmt,
 508		     unsigned long address)
 509{
 510#ifdef CONFIG_KALLSYMS
 511	char str[KSYM_SYMBOL_LEN];
 512	const char *name;
 513
 514	sprint_symbol(str, address);
 515	name = kretprobed(str);
 516
 517	return trace_seq_printf(s, fmt, name);
 
 
 
 518#endif
 519	return 1;
 520}
 521
 522#ifndef CONFIG_64BIT
 523# define IP_FMT "%08lx"
 524#else
 525# define IP_FMT "%016lx"
 526#endif
 527
 528int seq_print_user_ip(struct trace_seq *s, struct mm_struct *mm,
 529		      unsigned long ip, unsigned long sym_flags)
 530{
 531	struct file *file = NULL;
 532	unsigned long vmstart = 0;
 533	int ret = 1;
 534
 535	if (s->full)
 536		return 0;
 537
 538	if (mm) {
 539		const struct vm_area_struct *vma;
 540
 541		down_read(&mm->mmap_sem);
 542		vma = find_vma(mm, ip);
 543		if (vma) {
 544			file = vma->vm_file;
 545			vmstart = vma->vm_start;
 546		}
 547		if (file) {
 548			ret = trace_seq_path(s, &file->f_path);
 549			if (ret)
 550				ret = trace_seq_printf(s, "[+0x%lx]",
 551						       ip - vmstart);
 552		}
 553		up_read(&mm->mmap_sem);
 554	}
 555	if (ret && ((sym_flags & TRACE_ITER_SYM_ADDR) || !file))
 556		ret = trace_seq_printf(s, " <" IP_FMT ">", ip);
 557	return ret;
 558}
 559
 560int
 561seq_print_userip_objs(const struct userstack_entry *entry, struct trace_seq *s,
 562		      unsigned long sym_flags)
 563{
 564	struct mm_struct *mm = NULL;
 565	int ret = 1;
 566	unsigned int i;
 567
 568	if (trace_flags & TRACE_ITER_SYM_USEROBJ) {
 569		struct task_struct *task;
 570		/*
 571		 * we do the lookup on the thread group leader,
 572		 * since individual threads might have already quit!
 573		 */
 574		rcu_read_lock();
 575		task = find_task_by_vpid(entry->tgid);
 576		if (task)
 577			mm = get_task_mm(task);
 578		rcu_read_unlock();
 579	}
 580
 581	for (i = 0; i < FTRACE_STACK_ENTRIES; i++) {
 582		unsigned long ip = entry->caller[i];
 583
 584		if (ip == ULONG_MAX || !ret)
 585			break;
 586		if (ret)
 587			ret = trace_seq_puts(s, " => ");
 588		if (!ip) {
 589			if (ret)
 590				ret = trace_seq_puts(s, "??");
 591			if (ret)
 592				ret = trace_seq_putc(s, '\n');
 593			continue;
 594		}
 595		if (!ret)
 596			break;
 597		if (ret)
 598			ret = seq_print_user_ip(s, mm, ip, sym_flags);
 599		ret = trace_seq_putc(s, '\n');
 600	}
 601
 602	if (mm)
 603		mmput(mm);
 604	return ret;
 605}
 606
 607int
 608seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags)
 609{
 610	int ret;
 611
 612	if (!ip)
 613		return trace_seq_putc(s, '0');
 614
 615	if (sym_flags & TRACE_ITER_SYM_OFFSET)
 616		ret = seq_print_sym_offset(s, "%s", ip);
 617	else
 618		ret = seq_print_sym_short(s, "%s", ip);
 619
 620	if (!ret)
 621		return 0;
 622
 623	if (sym_flags & TRACE_ITER_SYM_ADDR)
 624		ret = trace_seq_printf(s, " <" IP_FMT ">", ip);
 625	return ret;
 
 
 626}
 627
 628/**
 629 * trace_print_lat_fmt - print the irq, preempt and lockdep fields
 630 * @s: trace seq struct to write to
 631 * @entry: The trace entry field from the ring buffer
 632 *
 633 * Prints the generic fields of irqs off, in hard or softirq, preempt
 634 * count.
 635 */
 636int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
 637{
 638	char hardsoft_irq;
 639	char need_resched;
 640	char irqs_off;
 641	int hardirq;
 642	int softirq;
 643	int ret;
 644
 
 645	hardirq = entry->flags & TRACE_FLAG_HARDIRQ;
 646	softirq = entry->flags & TRACE_FLAG_SOFTIRQ;
 647
 648	irqs_off =
 649		(entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' :
 650		(entry->flags & TRACE_FLAG_IRQS_NOSUPPORT) ? 'X' :
 651		'.';
 652
 653	switch (entry->flags & (TRACE_FLAG_NEED_RESCHED |
 654				TRACE_FLAG_PREEMPT_RESCHED)) {
 655	case TRACE_FLAG_NEED_RESCHED | TRACE_FLAG_PREEMPT_RESCHED:
 656		need_resched = 'N';
 657		break;
 658	case TRACE_FLAG_NEED_RESCHED:
 659		need_resched = 'n';
 660		break;
 661	case TRACE_FLAG_PREEMPT_RESCHED:
 662		need_resched = 'p';
 663		break;
 664	default:
 665		need_resched = '.';
 666		break;
 667	}
 668
 669	hardsoft_irq =
 
 
 670		(hardirq && softirq) ? 'H' :
 671		hardirq ? 'h' :
 672		softirq ? 's' :
 673		'.';
 674
 675	if (!trace_seq_printf(s, "%c%c%c",
 676			      irqs_off, need_resched, hardsoft_irq))
 677		return 0;
 678
 679	if (entry->preempt_count)
 680		ret = trace_seq_printf(s, "%x", entry->preempt_count);
 681	else
 682		ret = trace_seq_putc(s, '.');
 683
 684	return ret;
 685}
 686
 687static int
 688lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu)
 689{
 690	char comm[TASK_COMM_LEN];
 691
 692	trace_find_cmdline(entry->pid, comm);
 693
 694	if (!trace_seq_printf(s, "%8.8s-%-5d %3d",
 695			      comm, entry->pid, cpu))
 696		return 0;
 697
 698	return trace_print_lat_fmt(s, entry);
 699}
 700
 701static unsigned long preempt_mark_thresh_us = 100;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 702
 703static int
 704lat_print_timestamp(struct trace_iterator *iter, u64 next_ts)
 705{
 706	unsigned long verbose = trace_flags & TRACE_ITER_VERBOSE;
 
 707	unsigned long in_ns = iter->iter_flags & TRACE_FILE_TIME_IN_NS;
 708	unsigned long long abs_ts = iter->ts - iter->trace_buffer->time_start;
 709	unsigned long long rel_ts = next_ts - iter->ts;
 710	struct trace_seq *s = &iter->seq;
 711
 712	if (in_ns) {
 713		abs_ts = ns2usecs(abs_ts);
 714		rel_ts = ns2usecs(rel_ts);
 715	}
 716
 717	if (verbose && in_ns) {
 718		unsigned long abs_usec = do_div(abs_ts, USEC_PER_MSEC);
 719		unsigned long abs_msec = (unsigned long)abs_ts;
 720		unsigned long rel_usec = do_div(rel_ts, USEC_PER_MSEC);
 721		unsigned long rel_msec = (unsigned long)rel_ts;
 722
 723		return trace_seq_printf(
 724				s, "[%08llx] %ld.%03ldms (+%ld.%03ldms): ",
 725				ns2usecs(iter->ts),
 726				abs_msec, abs_usec,
 727				rel_msec, rel_usec);
 
 728	} else if (verbose && !in_ns) {
 729		return trace_seq_printf(
 730				s, "[%016llx] %lld (+%lld): ",
 731				iter->ts, abs_ts, rel_ts);
 
 732	} else if (!verbose && in_ns) {
 733		return trace_seq_printf(
 734				s, " %4lldus%c: ",
 735				abs_ts,
 736				rel_ts > preempt_mark_thresh_us ? '!' :
 737				  rel_ts > 1 ? '+' : ' ');
 738	} else { /* !verbose && !in_ns */
 739		return trace_seq_printf(s, " %4lld: ", abs_ts);
 740	}
 
 
 741}
 742
 743int trace_print_context(struct trace_iterator *iter)
 744{
 
 745	struct trace_seq *s = &iter->seq;
 746	struct trace_entry *entry = iter->ent;
 747	unsigned long long t;
 748	unsigned long secs, usec_rem;
 749	char comm[TASK_COMM_LEN];
 750	int ret;
 751
 752	trace_find_cmdline(entry->pid, comm);
 753
 754	ret = trace_seq_printf(s, "%16s-%-5d [%03d] ",
 755			       comm, entry->pid, iter->cpu);
 756	if (!ret)
 757		return 0;
 758
 759	if (trace_flags & TRACE_ITER_IRQ_INFO) {
 760		ret = trace_print_lat_fmt(s, entry);
 761		if (!ret)
 762			return 0;
 763	}
 764
 
 
 
 
 
 765	if (iter->iter_flags & TRACE_FILE_TIME_IN_NS) {
 766		t = ns2usecs(iter->ts);
 767		usec_rem = do_div(t, USEC_PER_SEC);
 768		secs = (unsigned long)t;
 769		return trace_seq_printf(s, " %5lu.%06lu: ", secs, usec_rem);
 770	} else
 771		return trace_seq_printf(s, " %12llu: ", iter->ts);
 
 
 772}
 773
 774int trace_print_lat_context(struct trace_iterator *iter)
 775{
 776	u64 next_ts;
 777	int ret;
 778	/* trace_find_next_entry will reset ent_size */
 779	int ent_size = iter->ent_size;
 780	struct trace_seq *s = &iter->seq;
 781	struct trace_entry *entry = iter->ent,
 782			   *next_entry = trace_find_next_entry(iter, NULL,
 783							       &next_ts);
 784	unsigned long verbose = (trace_flags & TRACE_ITER_VERBOSE);
 785
 786	/* Restore the original ent_size */
 787	iter->ent_size = ent_size;
 788
 
 789	if (!next_entry)
 790		next_ts = iter->ts;
 791
 
 
 
 792	if (verbose) {
 793		char comm[TASK_COMM_LEN];
 794
 795		trace_find_cmdline(entry->pid, comm);
 796
 797		ret = trace_seq_printf(
 798				s, "%16s %5d %3d %d %08x %08lx ",
 799				comm, entry->pid, iter->cpu, entry->flags,
 800				entry->preempt_count, iter->idx);
 801	} else {
 802		ret = lat_print_generic(s, entry, iter->cpu);
 803	}
 804
 805	if (ret)
 806		ret = lat_print_timestamp(iter, next_ts);
 807
 808	return ret;
 809}
 810
 811static const char state_to_char[] = TASK_STATE_TO_CHAR_STR;
 812
 813static int task_state_char(unsigned long state)
 814{
 815	int bit = state ? __ffs(state) + 1 : 0;
 816
 817	return bit < sizeof(state_to_char) - 1 ? state_to_char[bit] : '?';
 818}
 819
 820/**
 821 * ftrace_find_event - find a registered event
 822 * @type: the type of event to look for
 823 *
 824 * Returns an event of type @type otherwise NULL
 825 * Called with trace_event_read_lock() held.
 826 */
 827struct trace_event *ftrace_find_event(int type)
 828{
 829	struct trace_event *event;
 830	unsigned key;
 831
 832	key = type & (EVENT_HASHSIZE - 1);
 833
 834	hlist_for_each_entry(event, &event_hash[key], node) {
 835		if (event->type == type)
 836			return event;
 837	}
 838
 839	return NULL;
 840}
 841
 842static LIST_HEAD(ftrace_event_list);
 843
 844static int trace_search_list(struct list_head **list)
 845{
 846	struct trace_event *e;
 847	int last = __TRACE_LAST_TYPE;
 848
 849	if (list_empty(&ftrace_event_list)) {
 850		*list = &ftrace_event_list;
 851		return last + 1;
 852	}
 853
 854	/*
 855	 * We used up all possible max events,
 856	 * lets see if somebody freed one.
 857	 */
 858	list_for_each_entry(e, &ftrace_event_list, list) {
 859		if (e->type != last + 1)
 860			break;
 861		last++;
 862	}
 863
 864	/* Did we used up all 65 thousand events??? */
 865	if ((last + 1) > FTRACE_MAX_EVENT)
 866		return 0;
 867
 868	*list = &e->list;
 869	return last + 1;
 870}
 871
 872void trace_event_read_lock(void)
 873{
 874	down_read(&trace_event_sem);
 875}
 876
 877void trace_event_read_unlock(void)
 878{
 879	up_read(&trace_event_sem);
 880}
 881
 882/**
 883 * register_ftrace_event - register output for an event type
 884 * @event: the event type to register
 885 *
 886 * Event types are stored in a hash and this hash is used to
 887 * find a way to print an event. If the @event->type is set
 888 * then it will use that type, otherwise it will assign a
 889 * type to use.
 890 *
 891 * If you assign your own type, please make sure it is added
 892 * to the trace_type enum in trace.h, to avoid collisions
 893 * with the dynamic types.
 894 *
 895 * Returns the event type number or zero on error.
 896 */
 897int register_ftrace_event(struct trace_event *event)
 898{
 899	unsigned key;
 900	int ret = 0;
 901
 902	down_write(&trace_event_sem);
 903
 904	if (WARN_ON(!event))
 905		goto out;
 906
 907	if (WARN_ON(!event->funcs))
 908		goto out;
 909
 910	INIT_LIST_HEAD(&event->list);
 911
 912	if (!event->type) {
 913		struct list_head *list = NULL;
 914
 915		if (next_event_type > FTRACE_MAX_EVENT) {
 916
 917			event->type = trace_search_list(&list);
 918			if (!event->type)
 919				goto out;
 920
 921		} else {
 922			
 923			event->type = next_event_type++;
 924			list = &ftrace_event_list;
 925		}
 926
 927		if (WARN_ON(ftrace_find_event(event->type)))
 928			goto out;
 929
 930		list_add_tail(&event->list, list);
 931
 932	} else if (event->type > __TRACE_LAST_TYPE) {
 933		printk(KERN_WARNING "Need to add type to trace.h\n");
 934		WARN_ON(1);
 935		goto out;
 936	} else {
 937		/* Is this event already used */
 938		if (ftrace_find_event(event->type))
 939			goto out;
 940	}
 941
 942	if (event->funcs->trace == NULL)
 943		event->funcs->trace = trace_nop_print;
 944	if (event->funcs->raw == NULL)
 945		event->funcs->raw = trace_nop_print;
 946	if (event->funcs->hex == NULL)
 947		event->funcs->hex = trace_nop_print;
 948	if (event->funcs->binary == NULL)
 949		event->funcs->binary = trace_nop_print;
 950
 951	key = event->type & (EVENT_HASHSIZE - 1);
 952
 953	hlist_add_head(&event->node, &event_hash[key]);
 954
 955	ret = event->type;
 956 out:
 957	up_write(&trace_event_sem);
 958
 959	return ret;
 960}
 961EXPORT_SYMBOL_GPL(register_ftrace_event);
 962
 963/*
 964 * Used by module code with the trace_event_sem held for write.
 965 */
 966int __unregister_ftrace_event(struct trace_event *event)
 967{
 968	hlist_del(&event->node);
 969	list_del(&event->list);
 970	return 0;
 971}
 972
 973/**
 974 * unregister_ftrace_event - remove a no longer used event
 975 * @event: the event to remove
 976 */
 977int unregister_ftrace_event(struct trace_event *event)
 978{
 979	down_write(&trace_event_sem);
 980	__unregister_ftrace_event(event);
 981	up_write(&trace_event_sem);
 982
 983	return 0;
 984}
 985EXPORT_SYMBOL_GPL(unregister_ftrace_event);
 986
 987/*
 988 * Standard events
 989 */
 990
 991enum print_line_t trace_nop_print(struct trace_iterator *iter, int flags,
 992				  struct trace_event *event)
 993{
 994	if (!trace_seq_printf(&iter->seq, "type: %d\n", iter->ent->type))
 995		return TRACE_TYPE_PARTIAL_LINE;
 996
 997	return TRACE_TYPE_HANDLED;
 998}
 999
1000/* TRACE_FN */
1001static enum print_line_t trace_fn_trace(struct trace_iterator *iter, int flags,
1002					struct trace_event *event)
1003{
1004	struct ftrace_entry *field;
1005	struct trace_seq *s = &iter->seq;
1006
1007	trace_assign_type(field, iter->ent);
1008
1009	if (!seq_print_ip_sym(s, field->ip, flags))
1010		goto partial;
1011
1012	if ((flags & TRACE_ITER_PRINT_PARENT) && field->parent_ip) {
1013		if (!trace_seq_puts(s, " <-"))
1014			goto partial;
1015		if (!seq_print_ip_sym(s,
1016				      field->parent_ip,
1017				      flags))
1018			goto partial;
1019	}
1020	if (!trace_seq_putc(s, '\n'))
1021		goto partial;
1022
1023	return TRACE_TYPE_HANDLED;
1024
1025 partial:
1026	return TRACE_TYPE_PARTIAL_LINE;
1027}
1028
1029static enum print_line_t trace_fn_raw(struct trace_iterator *iter, int flags,
1030				      struct trace_event *event)
1031{
1032	struct ftrace_entry *field;
1033
1034	trace_assign_type(field, iter->ent);
1035
1036	if (!trace_seq_printf(&iter->seq, "%lx %lx\n",
1037			      field->ip,
1038			      field->parent_ip))
1039		return TRACE_TYPE_PARTIAL_LINE;
1040
1041	return TRACE_TYPE_HANDLED;
1042}
1043
1044static enum print_line_t trace_fn_hex(struct trace_iterator *iter, int flags,
1045				      struct trace_event *event)
1046{
1047	struct ftrace_entry *field;
1048	struct trace_seq *s = &iter->seq;
1049
1050	trace_assign_type(field, iter->ent);
1051
1052	SEQ_PUT_HEX_FIELD_RET(s, field->ip);
1053	SEQ_PUT_HEX_FIELD_RET(s, field->parent_ip);
1054
1055	return TRACE_TYPE_HANDLED;
1056}
1057
1058static enum print_line_t trace_fn_bin(struct trace_iterator *iter, int flags,
1059				      struct trace_event *event)
1060{
1061	struct ftrace_entry *field;
1062	struct trace_seq *s = &iter->seq;
1063
1064	trace_assign_type(field, iter->ent);
1065
1066	SEQ_PUT_FIELD_RET(s, field->ip);
1067	SEQ_PUT_FIELD_RET(s, field->parent_ip);
1068
1069	return TRACE_TYPE_HANDLED;
1070}
1071
1072static struct trace_event_functions trace_fn_funcs = {
1073	.trace		= trace_fn_trace,
1074	.raw		= trace_fn_raw,
1075	.hex		= trace_fn_hex,
1076	.binary		= trace_fn_bin,
1077};
1078
1079static struct trace_event trace_fn_event = {
1080	.type		= TRACE_FN,
1081	.funcs		= &trace_fn_funcs,
1082};
1083
1084/* TRACE_CTX an TRACE_WAKE */
1085static enum print_line_t trace_ctxwake_print(struct trace_iterator *iter,
1086					     char *delim)
1087{
1088	struct ctx_switch_entry *field;
1089	char comm[TASK_COMM_LEN];
1090	int S, T;
1091
1092
1093	trace_assign_type(field, iter->ent);
1094
1095	T = task_state_char(field->next_state);
1096	S = task_state_char(field->prev_state);
1097	trace_find_cmdline(field->next_pid, comm);
1098	if (!trace_seq_printf(&iter->seq,
1099			      " %5d:%3d:%c %s [%03d] %5d:%3d:%c %s\n",
1100			      field->prev_pid,
1101			      field->prev_prio,
1102			      S, delim,
1103			      field->next_cpu,
1104			      field->next_pid,
1105			      field->next_prio,
1106			      T, comm))
1107		return TRACE_TYPE_PARTIAL_LINE;
1108
1109	return TRACE_TYPE_HANDLED;
1110}
1111
1112static enum print_line_t trace_ctx_print(struct trace_iterator *iter, int flags,
1113					 struct trace_event *event)
1114{
1115	return trace_ctxwake_print(iter, "==>");
1116}
1117
1118static enum print_line_t trace_wake_print(struct trace_iterator *iter,
1119					  int flags, struct trace_event *event)
1120{
1121	return trace_ctxwake_print(iter, "  +");
1122}
1123
1124static int trace_ctxwake_raw(struct trace_iterator *iter, char S)
1125{
1126	struct ctx_switch_entry *field;
1127	int T;
1128
1129	trace_assign_type(field, iter->ent);
1130
1131	if (!S)
1132		S = task_state_char(field->prev_state);
1133	T = task_state_char(field->next_state);
1134	if (!trace_seq_printf(&iter->seq, "%d %d %c %d %d %d %c\n",
1135			      field->prev_pid,
1136			      field->prev_prio,
1137			      S,
1138			      field->next_cpu,
1139			      field->next_pid,
1140			      field->next_prio,
1141			      T))
1142		return TRACE_TYPE_PARTIAL_LINE;
1143
1144	return TRACE_TYPE_HANDLED;
1145}
1146
1147static enum print_line_t trace_ctx_raw(struct trace_iterator *iter, int flags,
1148				       struct trace_event *event)
1149{
1150	return trace_ctxwake_raw(iter, 0);
1151}
1152
1153static enum print_line_t trace_wake_raw(struct trace_iterator *iter, int flags,
1154					struct trace_event *event)
1155{
1156	return trace_ctxwake_raw(iter, '+');
1157}
1158
1159
1160static int trace_ctxwake_hex(struct trace_iterator *iter, char S)
1161{
1162	struct ctx_switch_entry *field;
1163	struct trace_seq *s = &iter->seq;
1164	int T;
1165
1166	trace_assign_type(field, iter->ent);
1167
1168	if (!S)
1169		S = task_state_char(field->prev_state);
1170	T = task_state_char(field->next_state);
1171
1172	SEQ_PUT_HEX_FIELD_RET(s, field->prev_pid);
1173	SEQ_PUT_HEX_FIELD_RET(s, field->prev_prio);
1174	SEQ_PUT_HEX_FIELD_RET(s, S);
1175	SEQ_PUT_HEX_FIELD_RET(s, field->next_cpu);
1176	SEQ_PUT_HEX_FIELD_RET(s, field->next_pid);
1177	SEQ_PUT_HEX_FIELD_RET(s, field->next_prio);
1178	SEQ_PUT_HEX_FIELD_RET(s, T);
1179
1180	return TRACE_TYPE_HANDLED;
1181}
1182
1183static enum print_line_t trace_ctx_hex(struct trace_iterator *iter, int flags,
1184				       struct trace_event *event)
1185{
1186	return trace_ctxwake_hex(iter, 0);
1187}
1188
1189static enum print_line_t trace_wake_hex(struct trace_iterator *iter, int flags,
1190					struct trace_event *event)
1191{
1192	return trace_ctxwake_hex(iter, '+');
1193}
1194
1195static enum print_line_t trace_ctxwake_bin(struct trace_iterator *iter,
1196					   int flags, struct trace_event *event)
1197{
1198	struct ctx_switch_entry *field;
1199	struct trace_seq *s = &iter->seq;
1200
1201	trace_assign_type(field, iter->ent);
1202
1203	SEQ_PUT_FIELD_RET(s, field->prev_pid);
1204	SEQ_PUT_FIELD_RET(s, field->prev_prio);
1205	SEQ_PUT_FIELD_RET(s, field->prev_state);
1206	SEQ_PUT_FIELD_RET(s, field->next_pid);
1207	SEQ_PUT_FIELD_RET(s, field->next_prio);
1208	SEQ_PUT_FIELD_RET(s, field->next_state);
 
1209
1210	return TRACE_TYPE_HANDLED;
1211}
1212
1213static struct trace_event_functions trace_ctx_funcs = {
1214	.trace		= trace_ctx_print,
1215	.raw		= trace_ctx_raw,
1216	.hex		= trace_ctx_hex,
1217	.binary		= trace_ctxwake_bin,
1218};
1219
1220static struct trace_event trace_ctx_event = {
1221	.type		= TRACE_CTX,
1222	.funcs		= &trace_ctx_funcs,
1223};
1224
1225static struct trace_event_functions trace_wake_funcs = {
1226	.trace		= trace_wake_print,
1227	.raw		= trace_wake_raw,
1228	.hex		= trace_wake_hex,
1229	.binary		= trace_ctxwake_bin,
1230};
1231
1232static struct trace_event trace_wake_event = {
1233	.type		= TRACE_WAKE,
1234	.funcs		= &trace_wake_funcs,
1235};
1236
1237/* TRACE_STACK */
1238
1239static enum print_line_t trace_stack_print(struct trace_iterator *iter,
1240					   int flags, struct trace_event *event)
1241{
1242	struct stack_entry *field;
1243	struct trace_seq *s = &iter->seq;
1244	unsigned long *p;
1245	unsigned long *end;
1246
1247	trace_assign_type(field, iter->ent);
1248	end = (unsigned long *)((long)iter->ent + iter->ent_size);
1249
1250	if (!trace_seq_puts(s, "<stack trace>\n"))
1251		goto partial;
1252
1253	for (p = field->caller; p && *p != ULONG_MAX && p < end; p++) {
1254		if (!trace_seq_puts(s, " => "))
1255			goto partial;
1256
1257		if (!seq_print_ip_sym(s, *p, flags))
1258			goto partial;
1259		if (!trace_seq_putc(s, '\n'))
1260			goto partial;
1261	}
1262
1263	return TRACE_TYPE_HANDLED;
 
 
 
1264
1265 partial:
1266	return TRACE_TYPE_PARTIAL_LINE;
1267}
1268
1269static struct trace_event_functions trace_stack_funcs = {
1270	.trace		= trace_stack_print,
1271};
1272
1273static struct trace_event trace_stack_event = {
1274	.type		= TRACE_STACK,
1275	.funcs		= &trace_stack_funcs,
1276};
1277
1278/* TRACE_USER_STACK */
1279static enum print_line_t trace_user_stack_print(struct trace_iterator *iter,
1280						int flags, struct trace_event *event)
1281{
 
1282	struct userstack_entry *field;
1283	struct trace_seq *s = &iter->seq;
 
 
1284
1285	trace_assign_type(field, iter->ent);
1286
1287	if (!trace_seq_puts(s, "<user stack trace>\n"))
1288		goto partial;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1289
1290	if (!seq_print_userip_objs(field, s, flags))
1291		goto partial;
 
 
1292
1293	return TRACE_TYPE_HANDLED;
 
1294
1295 partial:
1296	return TRACE_TYPE_PARTIAL_LINE;
1297}
1298
1299static struct trace_event_functions trace_user_stack_funcs = {
1300	.trace		= trace_user_stack_print,
1301};
1302
1303static struct trace_event trace_user_stack_event = {
1304	.type		= TRACE_USER_STACK,
1305	.funcs		= &trace_user_stack_funcs,
1306};
1307
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1308/* TRACE_BPUTS */
1309static enum print_line_t
1310trace_bputs_print(struct trace_iterator *iter, int flags,
1311		   struct trace_event *event)
1312{
1313	struct trace_entry *entry = iter->ent;
1314	struct trace_seq *s = &iter->seq;
1315	struct bputs_entry *field;
1316
1317	trace_assign_type(field, entry);
1318
1319	if (!seq_print_ip_sym(s, field->ip, flags))
1320		goto partial;
1321
1322	if (!trace_seq_puts(s, ": "))
1323		goto partial;
1324
1325	if (!trace_seq_puts(s, field->str))
1326		goto partial;
1327
1328	return TRACE_TYPE_HANDLED;
1329
1330 partial:
1331	return TRACE_TYPE_PARTIAL_LINE;
1332}
1333
1334
1335static enum print_line_t
1336trace_bputs_raw(struct trace_iterator *iter, int flags,
1337		struct trace_event *event)
1338{
1339	struct bputs_entry *field;
1340	struct trace_seq *s = &iter->seq;
1341
1342	trace_assign_type(field, iter->ent);
1343
1344	if (!trace_seq_printf(s, ": %lx : ", field->ip))
1345		goto partial;
1346
1347	if (!trace_seq_puts(s, field->str))
1348		goto partial;
1349
1350	return TRACE_TYPE_HANDLED;
1351
1352 partial:
1353	return TRACE_TYPE_PARTIAL_LINE;
1354}
1355
1356static struct trace_event_functions trace_bputs_funcs = {
1357	.trace		= trace_bputs_print,
1358	.raw		= trace_bputs_raw,
1359};
1360
1361static struct trace_event trace_bputs_event = {
1362	.type		= TRACE_BPUTS,
1363	.funcs		= &trace_bputs_funcs,
1364};
1365
1366/* TRACE_BPRINT */
1367static enum print_line_t
1368trace_bprint_print(struct trace_iterator *iter, int flags,
1369		   struct trace_event *event)
1370{
1371	struct trace_entry *entry = iter->ent;
1372	struct trace_seq *s = &iter->seq;
1373	struct bprint_entry *field;
1374
1375	trace_assign_type(field, entry);
1376
1377	if (!seq_print_ip_sym(s, field->ip, flags))
1378		goto partial;
1379
1380	if (!trace_seq_puts(s, ": "))
1381		goto partial;
1382
1383	if (!trace_seq_bprintf(s, field->fmt, field->buf))
1384		goto partial;
1385
1386	return TRACE_TYPE_HANDLED;
1387
1388 partial:
1389	return TRACE_TYPE_PARTIAL_LINE;
1390}
1391
1392
1393static enum print_line_t
1394trace_bprint_raw(struct trace_iterator *iter, int flags,
1395		 struct trace_event *event)
1396{
1397	struct bprint_entry *field;
1398	struct trace_seq *s = &iter->seq;
1399
1400	trace_assign_type(field, iter->ent);
1401
1402	if (!trace_seq_printf(s, ": %lx : ", field->ip))
1403		goto partial;
1404
1405	if (!trace_seq_bprintf(s, field->fmt, field->buf))
1406		goto partial;
1407
1408	return TRACE_TYPE_HANDLED;
1409
1410 partial:
1411	return TRACE_TYPE_PARTIAL_LINE;
1412}
1413
1414static struct trace_event_functions trace_bprint_funcs = {
1415	.trace		= trace_bprint_print,
1416	.raw		= trace_bprint_raw,
1417};
1418
1419static struct trace_event trace_bprint_event = {
1420	.type		= TRACE_BPRINT,
1421	.funcs		= &trace_bprint_funcs,
1422};
1423
1424/* TRACE_PRINT */
1425static enum print_line_t trace_print_print(struct trace_iterator *iter,
1426					   int flags, struct trace_event *event)
1427{
1428	struct print_entry *field;
1429	struct trace_seq *s = &iter->seq;
1430
1431	trace_assign_type(field, iter->ent);
1432
1433	if (!seq_print_ip_sym(s, field->ip, flags))
1434		goto partial;
1435
1436	if (!trace_seq_printf(s, ": %s", field->buf))
1437		goto partial;
1438
1439	return TRACE_TYPE_HANDLED;
1440
1441 partial:
1442	return TRACE_TYPE_PARTIAL_LINE;
1443}
1444
1445static enum print_line_t trace_print_raw(struct trace_iterator *iter, int flags,
1446					 struct trace_event *event)
1447{
1448	struct print_entry *field;
1449
1450	trace_assign_type(field, iter->ent);
1451
1452	if (!trace_seq_printf(&iter->seq, "# %lx %s", field->ip, field->buf))
1453		goto partial;
1454
1455	return TRACE_TYPE_HANDLED;
1456
1457 partial:
1458	return TRACE_TYPE_PARTIAL_LINE;
1459}
1460
1461static struct trace_event_functions trace_print_funcs = {
1462	.trace		= trace_print_print,
1463	.raw		= trace_print_raw,
1464};
1465
1466static struct trace_event trace_print_event = {
1467	.type	 	= TRACE_PRINT,
1468	.funcs		= &trace_print_funcs,
1469};
1470
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1471
1472static struct trace_event *events[] __initdata = {
1473	&trace_fn_event,
1474	&trace_ctx_event,
1475	&trace_wake_event,
1476	&trace_stack_event,
1477	&trace_user_stack_event,
1478	&trace_bputs_event,
1479	&trace_bprint_event,
1480	&trace_print_event,
 
 
1481	NULL
1482};
1483
1484__init static int init_events(void)
1485{
1486	struct trace_event *event;
1487	int i, ret;
1488
1489	for (i = 0; events[i]; i++) {
1490		event = events[i];
1491
1492		ret = register_ftrace_event(event);
1493		if (!ret) {
1494			printk(KERN_WARNING "event %d failed to register\n",
1495			       event->type);
1496			WARN_ON_ONCE(1);
1497		}
1498	}
1499
1500	return 0;
1501}
1502early_initcall(init_events);
v5.9
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * trace_output.c
   4 *
   5 * Copyright (C) 2008 Red Hat Inc, Steven Rostedt <srostedt@redhat.com>
   6 *
   7 */
 
   8#include <linux/module.h>
   9#include <linux/mutex.h>
  10#include <linux/ftrace.h>
  11#include <linux/sched/clock.h>
  12#include <linux/sched/mm.h>
  13
  14#include "trace_output.h"
  15
  16/* must be a power of 2 */
  17#define EVENT_HASHSIZE	128
  18
  19DECLARE_RWSEM(trace_event_sem);
  20
  21static struct hlist_head event_hash[EVENT_HASHSIZE] __read_mostly;
  22
  23static int next_event_type = __TRACE_LAST_TYPE;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  24
  25enum print_line_t trace_print_bputs_msg_only(struct trace_iterator *iter)
  26{
  27	struct trace_seq *s = &iter->seq;
  28	struct trace_entry *entry = iter->ent;
  29	struct bputs_entry *field;
 
  30
  31	trace_assign_type(field, entry);
  32
  33	trace_seq_puts(s, field->str);
 
 
  34
  35	return trace_handle_return(s);
  36}
  37
  38enum print_line_t trace_print_bprintk_msg_only(struct trace_iterator *iter)
  39{
  40	struct trace_seq *s = &iter->seq;
  41	struct trace_entry *entry = iter->ent;
  42	struct bprint_entry *field;
 
  43
  44	trace_assign_type(field, entry);
  45
  46	trace_seq_bprintf(s, field->fmt, field->buf);
 
 
  47
  48	return trace_handle_return(s);
  49}
  50
  51enum print_line_t trace_print_printk_msg_only(struct trace_iterator *iter)
  52{
  53	struct trace_seq *s = &iter->seq;
  54	struct trace_entry *entry = iter->ent;
  55	struct print_entry *field;
 
  56
  57	trace_assign_type(field, entry);
  58
  59	trace_seq_puts(s, field->buf);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  60
  61	return trace_handle_return(s);
  62}
 
  63
  64const char *
  65trace_print_flags_seq(struct trace_seq *p, const char *delim,
  66		      unsigned long flags,
  67		      const struct trace_print_flags *flag_array)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  68{
  69	unsigned long mask;
  70	const char *str;
  71	const char *ret = trace_seq_buffer_ptr(p);
  72	int i, first = 1;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  73
  74	for (i = 0;  flag_array[i].name && flags; i++) {
 
 
 
 
 
 
 
 
 
 
 
 
  75
  76		mask = flag_array[i].mask;
  77		if ((flags & mask) != mask)
  78			continue;
  79
  80		str = flag_array[i].name;
  81		flags &= ~mask;
  82		if (!first && delim)
  83			trace_seq_puts(p, delim);
  84		else
  85			first = 0;
  86		trace_seq_puts(p, str);
  87	}
  88
  89	/* check for left over flags */
  90	if (flags) {
  91		if (!first && delim)
  92			trace_seq_puts(p, delim);
  93		trace_seq_printf(p, "0x%lx", flags);
 
 
 
 
 
 
 
 
 
  94	}
  95
  96	trace_seq_putc(p, 0);
  97
  98	return ret;
  99}
 100EXPORT_SYMBOL(trace_print_flags_seq);
 101
 102const char *
 103trace_print_symbols_seq(struct trace_seq *p, unsigned long val,
 104			const struct trace_print_flags *symbol_array)
 105{
 106	int i;
 107	const char *ret = trace_seq_buffer_ptr(p);
 
 
 
 
 
 
 
 
 
 
 
 108
 109	for (i = 0;  symbol_array[i].name; i++) {
 
 
 
 
 110
 111		if (val != symbol_array[i].mask)
 112			continue;
 113
 114		trace_seq_puts(p, symbol_array[i].name);
 115		break;
 
 
 
 
 
 116	}
 
 
 
 
 
 
 
 
 
 
 
 117
 118	if (ret == (const char *)(trace_seq_buffer_ptr(p)))
 119		trace_seq_printf(p, "0x%lx", val);
 
 
 120
 121	trace_seq_putc(p, 0);
 
 122
 123	return ret;
 124}
 125EXPORT_SYMBOL(trace_print_symbols_seq);
 126
 127#if BITS_PER_LONG == 32
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 128const char *
 129trace_print_flags_seq_u64(struct trace_seq *p, const char *delim,
 130		      unsigned long long flags,
 131		      const struct trace_print_flags_u64 *flag_array)
 132{
 133	unsigned long long mask;
 134	const char *str;
 135	const char *ret = trace_seq_buffer_ptr(p);
 136	int i, first = 1;
 137
 138	for (i = 0;  flag_array[i].name && flags; i++) {
 139
 140		mask = flag_array[i].mask;
 141		if ((flags & mask) != mask)
 142			continue;
 143
 144		str = flag_array[i].name;
 145		flags &= ~mask;
 146		if (!first && delim)
 147			trace_seq_puts(p, delim);
 148		else
 149			first = 0;
 150		trace_seq_puts(p, str);
 151	}
 152
 153	/* check for left over flags */
 154	if (flags) {
 155		if (!first && delim)
 156			trace_seq_puts(p, delim);
 157		trace_seq_printf(p, "0x%llx", flags);
 158	}
 159
 160	trace_seq_putc(p, 0);
 161
 162	return ret;
 163}
 164EXPORT_SYMBOL(trace_print_flags_seq_u64);
 165
 166const char *
 167trace_print_symbols_seq_u64(struct trace_seq *p, unsigned long long val,
 168			 const struct trace_print_flags_u64 *symbol_array)
 169{
 170	int i;
 171	const char *ret = trace_seq_buffer_ptr(p);
 172
 173	for (i = 0;  symbol_array[i].name; i++) {
 174
 175		if (val != symbol_array[i].mask)
 176			continue;
 177
 178		trace_seq_puts(p, symbol_array[i].name);
 179		break;
 180	}
 181
 182	if (ret == (const char *)(trace_seq_buffer_ptr(p)))
 183		trace_seq_printf(p, "0x%llx", val);
 184
 185	trace_seq_putc(p, 0);
 186
 187	return ret;
 188}
 189EXPORT_SYMBOL(trace_print_symbols_seq_u64);
 190#endif
 191
 
 192const char *
 193trace_print_bitmask_seq(struct trace_seq *p, void *bitmask_ptr,
 194			unsigned int bitmask_size)
 195{
 196	const char *ret = trace_seq_buffer_ptr(p);
 
 197
 198	trace_seq_bitmask(p, bitmask_ptr, bitmask_size * 8);
 199	trace_seq_putc(p, 0);
 
 
 200
 201	return ret;
 202}
 203EXPORT_SYMBOL_GPL(trace_print_bitmask_seq);
 204
 205/**
 206 * trace_print_hex_seq - print buffer as hex sequence
 207 * @p: trace seq struct to write to
 208 * @buf: The buffer to print
 209 * @buf_len: Length of @buf in bytes
 210 * @concatenate: Print @buf as single hex string or with spacing
 211 *
 212 * Prints the passed buffer as a hex sequence either as a whole,
 213 * single hex string if @concatenate is true or with spacing after
 214 * each byte in case @concatenate is false.
 215 */
 216const char *
 217trace_print_hex_seq(struct trace_seq *p, const unsigned char *buf, int buf_len,
 218		    bool concatenate)
 219{
 220	int i;
 221	const char *ret = trace_seq_buffer_ptr(p);
 222	const char *fmt = concatenate ? "%*phN" : "%*ph";
 223
 224	for (i = 0; i < buf_len; i += 16)
 225		trace_seq_printf(p, fmt, min(buf_len - i, 16), &buf[i]);
 226	trace_seq_putc(p, 0);
 227
 228	return ret;
 229}
 230EXPORT_SYMBOL(trace_print_hex_seq);
 
 231
 232const char *
 233trace_print_array_seq(struct trace_seq *p, const void *buf, int count,
 234		      size_t el_size)
 235{
 236	const char *ret = trace_seq_buffer_ptr(p);
 237	const char *prefix = "";
 238	void *ptr = (void *)buf;
 239	size_t buf_len = count * el_size;
 240
 241	trace_seq_putc(p, '{');
 242
 243	while (ptr < buf + buf_len) {
 244		switch (el_size) {
 245		case 1:
 246			trace_seq_printf(p, "%s0x%x", prefix,
 247					 *(u8 *)ptr);
 248			break;
 249		case 2:
 250			trace_seq_printf(p, "%s0x%x", prefix,
 251					 *(u16 *)ptr);
 252			break;
 253		case 4:
 254			trace_seq_printf(p, "%s0x%x", prefix,
 255					 *(u32 *)ptr);
 256			break;
 257		case 8:
 258			trace_seq_printf(p, "%s0x%llx", prefix,
 259					 *(u64 *)ptr);
 260			break;
 261		default:
 262			trace_seq_printf(p, "BAD SIZE:%zu 0x%x", el_size,
 263					 *(u8 *)ptr);
 264			el_size = 1;
 265		}
 266		prefix = ",";
 267		ptr += el_size;
 268	}
 269
 270	trace_seq_putc(p, '}');
 271	trace_seq_putc(p, 0);
 272
 273	return ret;
 274}
 275EXPORT_SYMBOL(trace_print_array_seq);
 276
 277const char *
 278trace_print_hex_dump_seq(struct trace_seq *p, const char *prefix_str,
 279			 int prefix_type, int rowsize, int groupsize,
 280			 const void *buf, size_t len, bool ascii)
 281{
 282	const char *ret = trace_seq_buffer_ptr(p);
 283
 284	trace_seq_putc(p, '\n');
 285	trace_seq_hex_dump(p, prefix_str, prefix_type,
 286			   rowsize, groupsize, buf, len, ascii);
 287	trace_seq_putc(p, 0);
 288	return ret;
 289}
 290EXPORT_SYMBOL(trace_print_hex_dump_seq);
 291
 292int trace_raw_output_prep(struct trace_iterator *iter,
 293			  struct trace_event *trace_event)
 294{
 295	struct trace_event_call *event;
 296	struct trace_seq *s = &iter->seq;
 297	struct trace_seq *p = &iter->tmp_seq;
 298	struct trace_entry *entry;
 
 299
 300	event = container_of(trace_event, struct trace_event_call, event);
 301	entry = iter->ent;
 302
 303	if (entry->type != event->event.type) {
 304		WARN_ON_ONCE(1);
 305		return TRACE_TYPE_UNHANDLED;
 306	}
 307
 308	trace_seq_init(p);
 309	trace_seq_printf(s, "%s: ", trace_event_name(event));
 
 
 310
 311	return trace_handle_return(s);
 312}
 313EXPORT_SYMBOL(trace_raw_output_prep);
 314
 315static int trace_output_raw(struct trace_iterator *iter, char *name,
 316			    char *fmt, va_list ap)
 317{
 318	struct trace_seq *s = &iter->seq;
 
 
 
 
 
 
 
 319
 320	trace_seq_printf(s, "%s: ", name);
 321	trace_seq_vprintf(s, fmt, ap);
 322
 323	return trace_handle_return(s);
 324}
 325
 326int trace_output_call(struct trace_iterator *iter, char *name, char *fmt, ...)
 327{
 328	va_list ap;
 329	int ret;
 330
 331	va_start(ap, fmt);
 332	ret = trace_output_raw(iter, name, fmt, ap);
 333	va_end(ap);
 334
 335	return ret;
 336}
 337EXPORT_SYMBOL_GPL(trace_output_call);
 338
 339#ifdef CONFIG_KRETPROBES
 340static inline const char *kretprobed(const char *name)
 341{
 342	static const char tramp_name[] = "kretprobe_trampoline";
 343	int size = sizeof(tramp_name);
 344
 345	if (strncmp(tramp_name, name, size) == 0)
 346		return "[unknown/kretprobe'd]";
 347	return name;
 348}
 349#else
 350static inline const char *kretprobed(const char *name)
 351{
 352	return name;
 353}
 354#endif /* CONFIG_KRETPROBES */
 355
 356static void
 357seq_print_sym(struct trace_seq *s, unsigned long address, bool offset)
 358{
 359#ifdef CONFIG_KALLSYMS
 360	char str[KSYM_SYMBOL_LEN];
 361	const char *name;
 362
 363	if (offset)
 364		sprint_symbol(str, address);
 365	else
 366		kallsyms_lookup(address, NULL, NULL, NULL, str);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 367	name = kretprobed(str);
 368
 369	if (name && strlen(name)) {
 370		trace_seq_puts(s, name);
 371		return;
 372	}
 373#endif
 374	trace_seq_printf(s, "0x%08lx", address);
 375}
 376
 377#ifndef CONFIG_64BIT
 378# define IP_FMT "%08lx"
 379#else
 380# define IP_FMT "%016lx"
 381#endif
 382
 383static int seq_print_user_ip(struct trace_seq *s, struct mm_struct *mm,
 384			     unsigned long ip, unsigned long sym_flags)
 385{
 386	struct file *file = NULL;
 387	unsigned long vmstart = 0;
 388	int ret = 1;
 389
 390	if (s->full)
 391		return 0;
 392
 393	if (mm) {
 394		const struct vm_area_struct *vma;
 395
 396		mmap_read_lock(mm);
 397		vma = find_vma(mm, ip);
 398		if (vma) {
 399			file = vma->vm_file;
 400			vmstart = vma->vm_start;
 401		}
 402		if (file) {
 403			ret = trace_seq_path(s, &file->f_path);
 404			if (ret)
 405				trace_seq_printf(s, "[+0x%lx]",
 406						 ip - vmstart);
 407		}
 408		mmap_read_unlock(mm);
 409	}
 410	if (ret && ((sym_flags & TRACE_ITER_SYM_ADDR) || !file))
 411		trace_seq_printf(s, " <" IP_FMT ">", ip);
 412	return !trace_seq_has_overflowed(s);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 413}
 414
 415int
 416seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags)
 417{
 418	if (!ip) {
 419		trace_seq_putc(s, '0');
 420		goto out;
 421	}
 
 
 
 
 
 422
 423	seq_print_sym(s, ip, sym_flags & TRACE_ITER_SYM_OFFSET);
 
 424
 425	if (sym_flags & TRACE_ITER_SYM_ADDR)
 426		trace_seq_printf(s, " <" IP_FMT ">", ip);
 427
 428 out:
 429	return !trace_seq_has_overflowed(s);
 430}
 431
 432/**
 433 * trace_print_lat_fmt - print the irq, preempt and lockdep fields
 434 * @s: trace seq struct to write to
 435 * @entry: The trace entry field from the ring buffer
 436 *
 437 * Prints the generic fields of irqs off, in hard or softirq, preempt
 438 * count.
 439 */
 440int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
 441{
 442	char hardsoft_irq;
 443	char need_resched;
 444	char irqs_off;
 445	int hardirq;
 446	int softirq;
 447	int nmi;
 448
 449	nmi = entry->flags & TRACE_FLAG_NMI;
 450	hardirq = entry->flags & TRACE_FLAG_HARDIRQ;
 451	softirq = entry->flags & TRACE_FLAG_SOFTIRQ;
 452
 453	irqs_off =
 454		(entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' :
 455		(entry->flags & TRACE_FLAG_IRQS_NOSUPPORT) ? 'X' :
 456		'.';
 457
 458	switch (entry->flags & (TRACE_FLAG_NEED_RESCHED |
 459				TRACE_FLAG_PREEMPT_RESCHED)) {
 460	case TRACE_FLAG_NEED_RESCHED | TRACE_FLAG_PREEMPT_RESCHED:
 461		need_resched = 'N';
 462		break;
 463	case TRACE_FLAG_NEED_RESCHED:
 464		need_resched = 'n';
 465		break;
 466	case TRACE_FLAG_PREEMPT_RESCHED:
 467		need_resched = 'p';
 468		break;
 469	default:
 470		need_resched = '.';
 471		break;
 472	}
 473
 474	hardsoft_irq =
 475		(nmi && hardirq)     ? 'Z' :
 476		nmi                  ? 'z' :
 477		(hardirq && softirq) ? 'H' :
 478		hardirq              ? 'h' :
 479		softirq              ? 's' :
 480		                       '.' ;
 481
 482	trace_seq_printf(s, "%c%c%c",
 483			 irqs_off, need_resched, hardsoft_irq);
 
 484
 485	if (entry->preempt_count)
 486		trace_seq_printf(s, "%x", entry->preempt_count);
 487	else
 488		trace_seq_putc(s, '.');
 489
 490	return !trace_seq_has_overflowed(s);
 491}
 492
 493static int
 494lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu)
 495{
 496	char comm[TASK_COMM_LEN];
 497
 498	trace_find_cmdline(entry->pid, comm);
 499
 500	trace_seq_printf(s, "%8.8s-%-7d %3d",
 501			 comm, entry->pid, cpu);
 
 502
 503	return trace_print_lat_fmt(s, entry);
 504}
 505
 506#undef MARK
 507#define MARK(v, s) {.val = v, .sym = s}
 508/* trace overhead mark */
 509static const struct trace_mark {
 510	unsigned long long	val; /* unit: nsec */
 511	char			sym;
 512} mark[] = {
 513	MARK(1000000000ULL	, '$'), /* 1 sec */
 514	MARK(100000000ULL	, '@'), /* 100 msec */
 515	MARK(10000000ULL	, '*'), /* 10 msec */
 516	MARK(1000000ULL		, '#'), /* 1000 usecs */
 517	MARK(100000ULL		, '!'), /* 100 usecs */
 518	MARK(10000ULL		, '+'), /* 10 usecs */
 519};
 520#undef MARK
 521
 522char trace_find_mark(unsigned long long d)
 523{
 524	int i;
 525	int size = ARRAY_SIZE(mark);
 526
 527	for (i = 0; i < size; i++) {
 528		if (d > mark[i].val)
 529			break;
 530	}
 531
 532	return (i == size) ? ' ' : mark[i].sym;
 533}
 534
 535static int
 536lat_print_timestamp(struct trace_iterator *iter, u64 next_ts)
 537{
 538	struct trace_array *tr = iter->tr;
 539	unsigned long verbose = tr->trace_flags & TRACE_ITER_VERBOSE;
 540	unsigned long in_ns = iter->iter_flags & TRACE_FILE_TIME_IN_NS;
 541	unsigned long long abs_ts = iter->ts - iter->array_buffer->time_start;
 542	unsigned long long rel_ts = next_ts - iter->ts;
 543	struct trace_seq *s = &iter->seq;
 544
 545	if (in_ns) {
 546		abs_ts = ns2usecs(abs_ts);
 547		rel_ts = ns2usecs(rel_ts);
 548	}
 549
 550	if (verbose && in_ns) {
 551		unsigned long abs_usec = do_div(abs_ts, USEC_PER_MSEC);
 552		unsigned long abs_msec = (unsigned long)abs_ts;
 553		unsigned long rel_usec = do_div(rel_ts, USEC_PER_MSEC);
 554		unsigned long rel_msec = (unsigned long)rel_ts;
 555
 556		trace_seq_printf(
 557			s, "[%08llx] %ld.%03ldms (+%ld.%03ldms): ",
 558			ns2usecs(iter->ts),
 559			abs_msec, abs_usec,
 560			rel_msec, rel_usec);
 561
 562	} else if (verbose && !in_ns) {
 563		trace_seq_printf(
 564			s, "[%016llx] %lld (+%lld): ",
 565			iter->ts, abs_ts, rel_ts);
 566
 567	} else if (!verbose && in_ns) {
 568		trace_seq_printf(
 569			s, " %4lldus%c: ",
 570			abs_ts,
 571			trace_find_mark(rel_ts * NSEC_PER_USEC));
 572
 573	} else { /* !verbose && !in_ns */
 574		trace_seq_printf(s, " %4lld: ", abs_ts);
 575	}
 576
 577	return !trace_seq_has_overflowed(s);
 578}
 579
 580int trace_print_context(struct trace_iterator *iter)
 581{
 582	struct trace_array *tr = iter->tr;
 583	struct trace_seq *s = &iter->seq;
 584	struct trace_entry *entry = iter->ent;
 585	unsigned long long t;
 586	unsigned long secs, usec_rem;
 587	char comm[TASK_COMM_LEN];
 
 588
 589	trace_find_cmdline(entry->pid, comm);
 590
 591	trace_seq_printf(s, "%16s-%-7d ", comm, entry->pid);
 592
 593	if (tr->trace_flags & TRACE_ITER_RECORD_TGID) {
 594		unsigned int tgid = trace_find_tgid(entry->pid);
 595
 596		if (!tgid)
 597			trace_seq_printf(s, "(-------) ");
 598		else
 599			trace_seq_printf(s, "(%7d) ", tgid);
 600	}
 601
 602	trace_seq_printf(s, "[%03d] ", iter->cpu);
 603
 604	if (tr->trace_flags & TRACE_ITER_IRQ_INFO)
 605		trace_print_lat_fmt(s, entry);
 606
 607	if (iter->iter_flags & TRACE_FILE_TIME_IN_NS) {
 608		t = ns2usecs(iter->ts);
 609		usec_rem = do_div(t, USEC_PER_SEC);
 610		secs = (unsigned long)t;
 611		trace_seq_printf(s, " %5lu.%06lu: ", secs, usec_rem);
 612	} else
 613		trace_seq_printf(s, " %12llu: ", iter->ts);
 614
 615	return !trace_seq_has_overflowed(s);
 616}
 617
 618int trace_print_lat_context(struct trace_iterator *iter)
 619{
 620	struct trace_entry *entry, *next_entry;
 621	struct trace_array *tr = iter->tr;
 
 
 622	struct trace_seq *s = &iter->seq;
 623	unsigned long verbose = (tr->trace_flags & TRACE_ITER_VERBOSE);
 624	u64 next_ts;
 
 
 
 
 
 625
 626	next_entry = trace_find_next_entry(iter, NULL, &next_ts);
 627	if (!next_entry)
 628		next_ts = iter->ts;
 629
 630	/* trace_find_next_entry() may change iter->ent */
 631	entry = iter->ent;
 632
 633	if (verbose) {
 634		char comm[TASK_COMM_LEN];
 635
 636		trace_find_cmdline(entry->pid, comm);
 637
 638		trace_seq_printf(
 639			s, "%16s %7d %3d %d %08x %08lx ",
 640			comm, entry->pid, iter->cpu, entry->flags,
 641			entry->preempt_count, iter->idx);
 642	} else {
 643		lat_print_generic(s, entry, iter->cpu);
 644	}
 645
 646	lat_print_timestamp(iter, next_ts);
 
 
 
 
 
 
 
 
 
 
 647
 648	return !trace_seq_has_overflowed(s);
 649}
 650
 651/**
 652 * ftrace_find_event - find a registered event
 653 * @type: the type of event to look for
 654 *
 655 * Returns an event of type @type otherwise NULL
 656 * Called with trace_event_read_lock() held.
 657 */
 658struct trace_event *ftrace_find_event(int type)
 659{
 660	struct trace_event *event;
 661	unsigned key;
 662
 663	key = type & (EVENT_HASHSIZE - 1);
 664
 665	hlist_for_each_entry(event, &event_hash[key], node) {
 666		if (event->type == type)
 667			return event;
 668	}
 669
 670	return NULL;
 671}
 672
 673static LIST_HEAD(ftrace_event_list);
 674
 675static int trace_search_list(struct list_head **list)
 676{
 677	struct trace_event *e;
 678	int next = __TRACE_LAST_TYPE;
 679
 680	if (list_empty(&ftrace_event_list)) {
 681		*list = &ftrace_event_list;
 682		return next;
 683	}
 684
 685	/*
 686	 * We used up all possible max events,
 687	 * lets see if somebody freed one.
 688	 */
 689	list_for_each_entry(e, &ftrace_event_list, list) {
 690		if (e->type != next)
 691			break;
 692		next++;
 693	}
 694
 695	/* Did we used up all 65 thousand events??? */
 696	if (next > TRACE_EVENT_TYPE_MAX)
 697		return 0;
 698
 699	*list = &e->list;
 700	return next;
 701}
 702
 703void trace_event_read_lock(void)
 704{
 705	down_read(&trace_event_sem);
 706}
 707
 708void trace_event_read_unlock(void)
 709{
 710	up_read(&trace_event_sem);
 711}
 712
 713/**
 714 * register_trace_event - register output for an event type
 715 * @event: the event type to register
 716 *
 717 * Event types are stored in a hash and this hash is used to
 718 * find a way to print an event. If the @event->type is set
 719 * then it will use that type, otherwise it will assign a
 720 * type to use.
 721 *
 722 * If you assign your own type, please make sure it is added
 723 * to the trace_type enum in trace.h, to avoid collisions
 724 * with the dynamic types.
 725 *
 726 * Returns the event type number or zero on error.
 727 */
 728int register_trace_event(struct trace_event *event)
 729{
 730	unsigned key;
 731	int ret = 0;
 732
 733	down_write(&trace_event_sem);
 734
 735	if (WARN_ON(!event))
 736		goto out;
 737
 738	if (WARN_ON(!event->funcs))
 739		goto out;
 740
 741	INIT_LIST_HEAD(&event->list);
 742
 743	if (!event->type) {
 744		struct list_head *list = NULL;
 745
 746		if (next_event_type > TRACE_EVENT_TYPE_MAX) {
 747
 748			event->type = trace_search_list(&list);
 749			if (!event->type)
 750				goto out;
 751
 752		} else {
 753
 754			event->type = next_event_type++;
 755			list = &ftrace_event_list;
 756		}
 757
 758		if (WARN_ON(ftrace_find_event(event->type)))
 759			goto out;
 760
 761		list_add_tail(&event->list, list);
 762
 763	} else if (event->type > __TRACE_LAST_TYPE) {
 764		printk(KERN_WARNING "Need to add type to trace.h\n");
 765		WARN_ON(1);
 766		goto out;
 767	} else {
 768		/* Is this event already used */
 769		if (ftrace_find_event(event->type))
 770			goto out;
 771	}
 772
 773	if (event->funcs->trace == NULL)
 774		event->funcs->trace = trace_nop_print;
 775	if (event->funcs->raw == NULL)
 776		event->funcs->raw = trace_nop_print;
 777	if (event->funcs->hex == NULL)
 778		event->funcs->hex = trace_nop_print;
 779	if (event->funcs->binary == NULL)
 780		event->funcs->binary = trace_nop_print;
 781
 782	key = event->type & (EVENT_HASHSIZE - 1);
 783
 784	hlist_add_head(&event->node, &event_hash[key]);
 785
 786	ret = event->type;
 787 out:
 788	up_write(&trace_event_sem);
 789
 790	return ret;
 791}
 792EXPORT_SYMBOL_GPL(register_trace_event);
 793
 794/*
 795 * Used by module code with the trace_event_sem held for write.
 796 */
 797int __unregister_trace_event(struct trace_event *event)
 798{
 799	hlist_del(&event->node);
 800	list_del(&event->list);
 801	return 0;
 802}
 803
 804/**
 805 * unregister_trace_event - remove a no longer used event
 806 * @event: the event to remove
 807 */
 808int unregister_trace_event(struct trace_event *event)
 809{
 810	down_write(&trace_event_sem);
 811	__unregister_trace_event(event);
 812	up_write(&trace_event_sem);
 813
 814	return 0;
 815}
 816EXPORT_SYMBOL_GPL(unregister_trace_event);
 817
 818/*
 819 * Standard events
 820 */
 821
 822enum print_line_t trace_nop_print(struct trace_iterator *iter, int flags,
 823				  struct trace_event *event)
 824{
 825	trace_seq_printf(&iter->seq, "type: %d\n", iter->ent->type);
 
 826
 827	return trace_handle_return(&iter->seq);
 828}
 829
 830/* TRACE_FN */
 831static enum print_line_t trace_fn_trace(struct trace_iterator *iter, int flags,
 832					struct trace_event *event)
 833{
 834	struct ftrace_entry *field;
 835	struct trace_seq *s = &iter->seq;
 836
 837	trace_assign_type(field, iter->ent);
 838
 839	seq_print_ip_sym(s, field->ip, flags);
 
 840
 841	if ((flags & TRACE_ITER_PRINT_PARENT) && field->parent_ip) {
 842		trace_seq_puts(s, " <-");
 843		seq_print_ip_sym(s, field->parent_ip, flags);
 
 
 
 
 844	}
 
 
 845
 846	trace_seq_putc(s, '\n');
 847
 848	return trace_handle_return(s);
 
 849}
 850
 851static enum print_line_t trace_fn_raw(struct trace_iterator *iter, int flags,
 852				      struct trace_event *event)
 853{
 854	struct ftrace_entry *field;
 855
 856	trace_assign_type(field, iter->ent);
 857
 858	trace_seq_printf(&iter->seq, "%lx %lx\n",
 859			 field->ip,
 860			 field->parent_ip);
 
 861
 862	return trace_handle_return(&iter->seq);
 863}
 864
 865static enum print_line_t trace_fn_hex(struct trace_iterator *iter, int flags,
 866				      struct trace_event *event)
 867{
 868	struct ftrace_entry *field;
 869	struct trace_seq *s = &iter->seq;
 870
 871	trace_assign_type(field, iter->ent);
 872
 873	SEQ_PUT_HEX_FIELD(s, field->ip);
 874	SEQ_PUT_HEX_FIELD(s, field->parent_ip);
 875
 876	return trace_handle_return(s);
 877}
 878
 879static enum print_line_t trace_fn_bin(struct trace_iterator *iter, int flags,
 880				      struct trace_event *event)
 881{
 882	struct ftrace_entry *field;
 883	struct trace_seq *s = &iter->seq;
 884
 885	trace_assign_type(field, iter->ent);
 886
 887	SEQ_PUT_FIELD(s, field->ip);
 888	SEQ_PUT_FIELD(s, field->parent_ip);
 889
 890	return trace_handle_return(s);
 891}
 892
 893static struct trace_event_functions trace_fn_funcs = {
 894	.trace		= trace_fn_trace,
 895	.raw		= trace_fn_raw,
 896	.hex		= trace_fn_hex,
 897	.binary		= trace_fn_bin,
 898};
 899
 900static struct trace_event trace_fn_event = {
 901	.type		= TRACE_FN,
 902	.funcs		= &trace_fn_funcs,
 903};
 904
 905/* TRACE_CTX an TRACE_WAKE */
 906static enum print_line_t trace_ctxwake_print(struct trace_iterator *iter,
 907					     char *delim)
 908{
 909	struct ctx_switch_entry *field;
 910	char comm[TASK_COMM_LEN];
 911	int S, T;
 912
 913
 914	trace_assign_type(field, iter->ent);
 915
 916	T = task_index_to_char(field->next_state);
 917	S = task_index_to_char(field->prev_state);
 918	trace_find_cmdline(field->next_pid, comm);
 919	trace_seq_printf(&iter->seq,
 920			 " %7d:%3d:%c %s [%03d] %7d:%3d:%c %s\n",
 921			 field->prev_pid,
 922			 field->prev_prio,
 923			 S, delim,
 924			 field->next_cpu,
 925			 field->next_pid,
 926			 field->next_prio,
 927			 T, comm);
 
 928
 929	return trace_handle_return(&iter->seq);
 930}
 931
 932static enum print_line_t trace_ctx_print(struct trace_iterator *iter, int flags,
 933					 struct trace_event *event)
 934{
 935	return trace_ctxwake_print(iter, "==>");
 936}
 937
 938static enum print_line_t trace_wake_print(struct trace_iterator *iter,
 939					  int flags, struct trace_event *event)
 940{
 941	return trace_ctxwake_print(iter, "  +");
 942}
 943
 944static int trace_ctxwake_raw(struct trace_iterator *iter, char S)
 945{
 946	struct ctx_switch_entry *field;
 947	int T;
 948
 949	trace_assign_type(field, iter->ent);
 950
 951	if (!S)
 952		S = task_index_to_char(field->prev_state);
 953	T = task_index_to_char(field->next_state);
 954	trace_seq_printf(&iter->seq, "%d %d %c %d %d %d %c\n",
 955			 field->prev_pid,
 956			 field->prev_prio,
 957			 S,
 958			 field->next_cpu,
 959			 field->next_pid,
 960			 field->next_prio,
 961			 T);
 
 962
 963	return trace_handle_return(&iter->seq);
 964}
 965
 966static enum print_line_t trace_ctx_raw(struct trace_iterator *iter, int flags,
 967				       struct trace_event *event)
 968{
 969	return trace_ctxwake_raw(iter, 0);
 970}
 971
 972static enum print_line_t trace_wake_raw(struct trace_iterator *iter, int flags,
 973					struct trace_event *event)
 974{
 975	return trace_ctxwake_raw(iter, '+');
 976}
 977
 978
 979static int trace_ctxwake_hex(struct trace_iterator *iter, char S)
 980{
 981	struct ctx_switch_entry *field;
 982	struct trace_seq *s = &iter->seq;
 983	int T;
 984
 985	trace_assign_type(field, iter->ent);
 986
 987	if (!S)
 988		S = task_index_to_char(field->prev_state);
 989	T = task_index_to_char(field->next_state);
 990
 991	SEQ_PUT_HEX_FIELD(s, field->prev_pid);
 992	SEQ_PUT_HEX_FIELD(s, field->prev_prio);
 993	SEQ_PUT_HEX_FIELD(s, S);
 994	SEQ_PUT_HEX_FIELD(s, field->next_cpu);
 995	SEQ_PUT_HEX_FIELD(s, field->next_pid);
 996	SEQ_PUT_HEX_FIELD(s, field->next_prio);
 997	SEQ_PUT_HEX_FIELD(s, T);
 998
 999	return trace_handle_return(s);
1000}
1001
1002static enum print_line_t trace_ctx_hex(struct trace_iterator *iter, int flags,
1003				       struct trace_event *event)
1004{
1005	return trace_ctxwake_hex(iter, 0);
1006}
1007
1008static enum print_line_t trace_wake_hex(struct trace_iterator *iter, int flags,
1009					struct trace_event *event)
1010{
1011	return trace_ctxwake_hex(iter, '+');
1012}
1013
1014static enum print_line_t trace_ctxwake_bin(struct trace_iterator *iter,
1015					   int flags, struct trace_event *event)
1016{
1017	struct ctx_switch_entry *field;
1018	struct trace_seq *s = &iter->seq;
1019
1020	trace_assign_type(field, iter->ent);
1021
1022	SEQ_PUT_FIELD(s, field->prev_pid);
1023	SEQ_PUT_FIELD(s, field->prev_prio);
1024	SEQ_PUT_FIELD(s, field->prev_state);
1025	SEQ_PUT_FIELD(s, field->next_cpu);
1026	SEQ_PUT_FIELD(s, field->next_pid);
1027	SEQ_PUT_FIELD(s, field->next_prio);
1028	SEQ_PUT_FIELD(s, field->next_state);
1029
1030	return trace_handle_return(s);
1031}
1032
1033static struct trace_event_functions trace_ctx_funcs = {
1034	.trace		= trace_ctx_print,
1035	.raw		= trace_ctx_raw,
1036	.hex		= trace_ctx_hex,
1037	.binary		= trace_ctxwake_bin,
1038};
1039
1040static struct trace_event trace_ctx_event = {
1041	.type		= TRACE_CTX,
1042	.funcs		= &trace_ctx_funcs,
1043};
1044
1045static struct trace_event_functions trace_wake_funcs = {
1046	.trace		= trace_wake_print,
1047	.raw		= trace_wake_raw,
1048	.hex		= trace_wake_hex,
1049	.binary		= trace_ctxwake_bin,
1050};
1051
1052static struct trace_event trace_wake_event = {
1053	.type		= TRACE_WAKE,
1054	.funcs		= &trace_wake_funcs,
1055};
1056
1057/* TRACE_STACK */
1058
1059static enum print_line_t trace_stack_print(struct trace_iterator *iter,
1060					   int flags, struct trace_event *event)
1061{
1062	struct stack_entry *field;
1063	struct trace_seq *s = &iter->seq;
1064	unsigned long *p;
1065	unsigned long *end;
1066
1067	trace_assign_type(field, iter->ent);
1068	end = (unsigned long *)((long)iter->ent + iter->ent_size);
1069
1070	trace_seq_puts(s, "<stack trace>\n");
 
1071
1072	for (p = field->caller; p && p < end && *p != ULONG_MAX; p++) {
 
 
1073
1074		if (trace_seq_has_overflowed(s))
1075			break;
 
 
 
1076
1077		trace_seq_puts(s, " => ");
1078		seq_print_ip_sym(s, *p, flags);
1079		trace_seq_putc(s, '\n');
1080	}
1081
1082	return trace_handle_return(s);
 
1083}
1084
1085static struct trace_event_functions trace_stack_funcs = {
1086	.trace		= trace_stack_print,
1087};
1088
1089static struct trace_event trace_stack_event = {
1090	.type		= TRACE_STACK,
1091	.funcs		= &trace_stack_funcs,
1092};
1093
1094/* TRACE_USER_STACK */
1095static enum print_line_t trace_user_stack_print(struct trace_iterator *iter,
1096						int flags, struct trace_event *event)
1097{
1098	struct trace_array *tr = iter->tr;
1099	struct userstack_entry *field;
1100	struct trace_seq *s = &iter->seq;
1101	struct mm_struct *mm = NULL;
1102	unsigned int i;
1103
1104	trace_assign_type(field, iter->ent);
1105
1106	trace_seq_puts(s, "<user stack trace>\n");
1107
1108	if (tr->trace_flags & TRACE_ITER_SYM_USEROBJ) {
1109		struct task_struct *task;
1110		/*
1111		 * we do the lookup on the thread group leader,
1112		 * since individual threads might have already quit!
1113		 */
1114		rcu_read_lock();
1115		task = find_task_by_vpid(field->tgid);
1116		if (task)
1117			mm = get_task_mm(task);
1118		rcu_read_unlock();
1119	}
1120
1121	for (i = 0; i < FTRACE_STACK_ENTRIES; i++) {
1122		unsigned long ip = field->caller[i];
1123
1124		if (!ip || trace_seq_has_overflowed(s))
1125			break;
1126
1127		trace_seq_puts(s, " => ");
1128		seq_print_user_ip(s, mm, ip, flags);
1129		trace_seq_putc(s, '\n');
1130	}
1131
1132	if (mm)
1133		mmput(mm);
1134
1135	return trace_handle_return(s);
 
1136}
1137
1138static struct trace_event_functions trace_user_stack_funcs = {
1139	.trace		= trace_user_stack_print,
1140};
1141
1142static struct trace_event trace_user_stack_event = {
1143	.type		= TRACE_USER_STACK,
1144	.funcs		= &trace_user_stack_funcs,
1145};
1146
1147/* TRACE_HWLAT */
1148static enum print_line_t
1149trace_hwlat_print(struct trace_iterator *iter, int flags,
1150		  struct trace_event *event)
1151{
1152	struct trace_entry *entry = iter->ent;
1153	struct trace_seq *s = &iter->seq;
1154	struct hwlat_entry *field;
1155
1156	trace_assign_type(field, entry);
1157
1158	trace_seq_printf(s, "#%-5u inner/outer(us): %4llu/%-5llu ts:%lld.%09ld count:%d",
1159			 field->seqnum,
1160			 field->duration,
1161			 field->outer_duration,
1162			 (long long)field->timestamp.tv_sec,
1163			 field->timestamp.tv_nsec, field->count);
1164
1165	if (field->nmi_count) {
1166		/*
1167		 * The generic sched_clock() is not NMI safe, thus
1168		 * we only record the count and not the time.
1169		 */
1170		if (!IS_ENABLED(CONFIG_GENERIC_SCHED_CLOCK))
1171			trace_seq_printf(s, " nmi-total:%llu",
1172					 field->nmi_total_ts);
1173		trace_seq_printf(s, " nmi-count:%u",
1174				 field->nmi_count);
1175	}
1176
1177	trace_seq_putc(s, '\n');
1178
1179	return trace_handle_return(s);
1180}
1181
1182
1183static enum print_line_t
1184trace_hwlat_raw(struct trace_iterator *iter, int flags,
1185		struct trace_event *event)
1186{
1187	struct hwlat_entry *field;
1188	struct trace_seq *s = &iter->seq;
1189
1190	trace_assign_type(field, iter->ent);
1191
1192	trace_seq_printf(s, "%llu %lld %lld %09ld %u\n",
1193			 field->duration,
1194			 field->outer_duration,
1195			 (long long)field->timestamp.tv_sec,
1196			 field->timestamp.tv_nsec,
1197			 field->seqnum);
1198
1199	return trace_handle_return(s);
1200}
1201
1202static struct trace_event_functions trace_hwlat_funcs = {
1203	.trace		= trace_hwlat_print,
1204	.raw		= trace_hwlat_raw,
1205};
1206
1207static struct trace_event trace_hwlat_event = {
1208	.type		= TRACE_HWLAT,
1209	.funcs		= &trace_hwlat_funcs,
1210};
1211
1212/* TRACE_BPUTS */
1213static enum print_line_t
1214trace_bputs_print(struct trace_iterator *iter, int flags,
1215		   struct trace_event *event)
1216{
1217	struct trace_entry *entry = iter->ent;
1218	struct trace_seq *s = &iter->seq;
1219	struct bputs_entry *field;
1220
1221	trace_assign_type(field, entry);
1222
1223	seq_print_ip_sym(s, field->ip, flags);
1224	trace_seq_puts(s, ": ");
1225	trace_seq_puts(s, field->str);
 
 
1226
1227	return trace_handle_return(s);
 
 
 
 
 
 
1228}
1229
1230
1231static enum print_line_t
1232trace_bputs_raw(struct trace_iterator *iter, int flags,
1233		struct trace_event *event)
1234{
1235	struct bputs_entry *field;
1236	struct trace_seq *s = &iter->seq;
1237
1238	trace_assign_type(field, iter->ent);
1239
1240	trace_seq_printf(s, ": %lx : ", field->ip);
1241	trace_seq_puts(s, field->str);
 
 
 
1242
1243	return trace_handle_return(s);
 
 
 
1244}
1245
1246static struct trace_event_functions trace_bputs_funcs = {
1247	.trace		= trace_bputs_print,
1248	.raw		= trace_bputs_raw,
1249};
1250
1251static struct trace_event trace_bputs_event = {
1252	.type		= TRACE_BPUTS,
1253	.funcs		= &trace_bputs_funcs,
1254};
1255
1256/* TRACE_BPRINT */
1257static enum print_line_t
1258trace_bprint_print(struct trace_iterator *iter, int flags,
1259		   struct trace_event *event)
1260{
1261	struct trace_entry *entry = iter->ent;
1262	struct trace_seq *s = &iter->seq;
1263	struct bprint_entry *field;
1264
1265	trace_assign_type(field, entry);
1266
1267	seq_print_ip_sym(s, field->ip, flags);
1268	trace_seq_puts(s, ": ");
1269	trace_seq_bprintf(s, field->fmt, field->buf);
 
 
1270
1271	return trace_handle_return(s);
 
 
 
 
 
 
1272}
1273
1274
1275static enum print_line_t
1276trace_bprint_raw(struct trace_iterator *iter, int flags,
1277		 struct trace_event *event)
1278{
1279	struct bprint_entry *field;
1280	struct trace_seq *s = &iter->seq;
1281
1282	trace_assign_type(field, iter->ent);
1283
1284	trace_seq_printf(s, ": %lx : ", field->ip);
1285	trace_seq_bprintf(s, field->fmt, field->buf);
 
 
 
1286
1287	return trace_handle_return(s);
 
 
 
1288}
1289
1290static struct trace_event_functions trace_bprint_funcs = {
1291	.trace		= trace_bprint_print,
1292	.raw		= trace_bprint_raw,
1293};
1294
1295static struct trace_event trace_bprint_event = {
1296	.type		= TRACE_BPRINT,
1297	.funcs		= &trace_bprint_funcs,
1298};
1299
1300/* TRACE_PRINT */
1301static enum print_line_t trace_print_print(struct trace_iterator *iter,
1302					   int flags, struct trace_event *event)
1303{
1304	struct print_entry *field;
1305	struct trace_seq *s = &iter->seq;
1306
1307	trace_assign_type(field, iter->ent);
1308
1309	seq_print_ip_sym(s, field->ip, flags);
1310	trace_seq_printf(s, ": %s", field->buf);
 
 
 
 
 
1311
1312	return trace_handle_return(s);
 
1313}
1314
1315static enum print_line_t trace_print_raw(struct trace_iterator *iter, int flags,
1316					 struct trace_event *event)
1317{
1318	struct print_entry *field;
1319
1320	trace_assign_type(field, iter->ent);
1321
1322	trace_seq_printf(&iter->seq, "# %lx %s", field->ip, field->buf);
 
1323
1324	return trace_handle_return(&iter->seq);
 
 
 
1325}
1326
1327static struct trace_event_functions trace_print_funcs = {
1328	.trace		= trace_print_print,
1329	.raw		= trace_print_raw,
1330};
1331
1332static struct trace_event trace_print_event = {
1333	.type	 	= TRACE_PRINT,
1334	.funcs		= &trace_print_funcs,
1335};
1336
1337static enum print_line_t trace_raw_data(struct trace_iterator *iter, int flags,
1338					 struct trace_event *event)
1339{
1340	struct raw_data_entry *field;
1341	int i;
1342
1343	trace_assign_type(field, iter->ent);
1344
1345	trace_seq_printf(&iter->seq, "# %x buf:", field->id);
1346
1347	for (i = 0; i < iter->ent_size - offsetof(struct raw_data_entry, buf); i++)
1348		trace_seq_printf(&iter->seq, " %02x",
1349				 (unsigned char)field->buf[i]);
1350
1351	trace_seq_putc(&iter->seq, '\n');
1352
1353	return trace_handle_return(&iter->seq);
1354}
1355
1356static struct trace_event_functions trace_raw_data_funcs = {
1357	.trace		= trace_raw_data,
1358	.raw		= trace_raw_data,
1359};
1360
1361static struct trace_event trace_raw_data_event = {
1362	.type	 	= TRACE_RAW_DATA,
1363	.funcs		= &trace_raw_data_funcs,
1364};
1365
1366
1367static struct trace_event *events[] __initdata = {
1368	&trace_fn_event,
1369	&trace_ctx_event,
1370	&trace_wake_event,
1371	&trace_stack_event,
1372	&trace_user_stack_event,
1373	&trace_bputs_event,
1374	&trace_bprint_event,
1375	&trace_print_event,
1376	&trace_hwlat_event,
1377	&trace_raw_data_event,
1378	NULL
1379};
1380
1381__init static int init_events(void)
1382{
1383	struct trace_event *event;
1384	int i, ret;
1385
1386	for (i = 0; events[i]; i++) {
1387		event = events[i];
1388
1389		ret = register_trace_event(event);
1390		if (!ret) {
1391			printk(KERN_WARNING "event %d failed to register\n",
1392			       event->type);
1393			WARN_ON_ONCE(1);
1394		}
1395	}
1396
1397	return 0;
1398}
1399early_initcall(init_events);