[mirror_ubuntu-bionic-kernel.git] / kernel / trace / trace_output.c

/*
 * trace_output.c
 *
 * Copyright (C) 2008 Red Hat Inc, Steven Rostedt <srostedt@redhat.com>
 *
 */

#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/ftrace.h>

#include "trace_output.h"

/* must be a power of 2 */
#define EVENT_HASHSIZE	128

static DEFINE_MUTEX(trace_event_mutex);
static struct hlist_head event_hash[EVENT_HASHSIZE] __read_mostly;

static int next_event_type = __TRACE_LAST_TYPE + 1;

/**
 * trace_seq_printf - sequence printing of trace information
 * @s: trace sequence descriptor
 * @fmt: printf format string
 *
 * The tracer may use either sequence operations or its own
 * copy to user routines. To simplify formating of a trace
 * trace_seq_printf is used to store strings into a special
 * buffer (@s). Then the output may be either used by
 * the sequencer or pulled into another buffer.
 */
int
trace_seq_printf(struct trace_seq *s, const char *fmt, ...)
{
	int len = (PAGE_SIZE - 1) - s->len;
	va_list ap;
	int ret;

	if (!len)
		return 0;

	va_start(ap, fmt);
	ret = vsnprintf(s->buffer + s->len, len, fmt, ap);
	va_end(ap);

	/* If we can't write it all, don't bother writing anything */
	if (ret >= len)
		return 0;

	s->len += ret;

	return len;
}

/**
 * trace_seq_puts - trace sequence printing of simple string
 * @s: trace sequence descriptor
 * @str: simple string to record
 *
 * The tracer may use either the sequence operations or its own
 * copy to user routines. This function records a simple string
 * into a special buffer (@s) for later retrieval by a sequencer
 * or other mechanism.
 */
int trace_seq_puts(struct trace_seq *s, const char *str)
{
	int len = strlen(str);

	if (len > ((PAGE_SIZE - 1) - s->len))
		return 0;

	memcpy(s->buffer + s->len, str, len);
	s->len += len;

	return len;
}

int trace_seq_putc(struct trace_seq *s, unsigned char c)
{
	if (s->len >= (PAGE_SIZE - 1))
		return 0;

	s->buffer[s->len++] = c;

	return 1;
}

int trace_seq_putmem(struct trace_seq *s, void *mem, size_t len)
{
	if (len > ((PAGE_SIZE - 1) - s->len))
		return 0;

	memcpy(s->buffer + s->len, mem, len);
	s->len += len;

	return len;
}

int trace_seq_putmem_hex(struct trace_seq *s, void *mem, size_t len)
{
	unsigned char hex[HEX_CHARS];
	unsigned char *data = mem;
	int i, j;

#ifdef __BIG_ENDIAN
	for (i = 0, j = 0; i < len; i++) {
#else
	for (i = len-1, j = 0; i >= 0; i--) {
#endif
		hex[j++] = hex_asc_hi(data[i]);
		hex[j++] = hex_asc_lo(data[i]);
	}
	hex[j++] = ' ';

	return trace_seq_putmem(s, hex, j);
}

int trace_seq_path(struct trace_seq *s, struct path *path)
{
	unsigned char *p;

	if (s->len >= (PAGE_SIZE - 1))
		return 0;
	p = d_path(path, s->buffer + s->len, PAGE_SIZE - s->len);
	if (!IS_ERR(p)) {
		p = mangle_path(s->buffer + s->len, p, "\n");
		if (p) {
			s->len = p - s->buffer;
			return 1;
		}
	} else {
		s->buffer[s->len++] = '?';
		return 1;
	}

	return 0;
}

#ifdef CONFIG_KRETPROBES
static inline const char *kretprobed(const char *name)
{
	static const char tramp_name[] = "kretprobe_trampoline";
	int size = sizeof(tramp_name);

	if (strncmp(tramp_name, name, size) == 0)
		return "[unknown/kretprobe'd]";
	return name;
}
#else
static inline const char *kretprobed(const char *name)
{
	return name;
}
#endif /* CONFIG_KRETPROBES */

static int
seq_print_sym_short(struct trace_seq *s, const char *fmt, unsigned long address)
{
#ifdef CONFIG_KALLSYMS
	char str[KSYM_SYMBOL_LEN];
	const char *name;

	kallsyms_lookup(address, NULL, NULL, NULL, str);

	name = kretprobed(str);

	return trace_seq_printf(s, fmt, name);
#endif
	return 1;
}

static int
seq_print_sym_offset(struct trace_seq *s, const char *fmt,
		     unsigned long address)
{
#ifdef CONFIG_KALLSYMS
	char str[KSYM_SYMBOL_LEN];
	const char *name;

	sprint_symbol(str, address);
	name = kretprobed(str);

	return trace_seq_printf(s, fmt, name);
#endif
	return 1;
}

#ifndef CONFIG_64BIT
# define IP_FMT "%08lx"
#else
# define IP_FMT "%016lx"
#endif

int seq_print_user_ip(struct trace_seq *s, struct mm_struct *mm,
		      unsigned long ip, unsigned long sym_flags)
{
	struct file *file = NULL;
	unsigned long vmstart = 0;
	int ret = 1;

	if (mm) {
		const struct vm_area_struct *vma;

		down_read(&mm->mmap_sem);
		vma = find_vma(mm, ip);
		if (vma) {
			file = vma->vm_file;
			vmstart = vma->vm_start;
		}
		if (file) {
			ret = trace_seq_path(s, &file->f_path);
			if (ret)
				ret = trace_seq_printf(s, "[+0x%lx]",
						       ip - vmstart);
		}
		up_read(&mm->mmap_sem);
	}
	if (ret && ((sym_flags & TRACE_ITER_SYM_ADDR) || !file))
		ret = trace_seq_printf(s, " <" IP_FMT ">", ip);
	return ret;
}

int
seq_print_userip_objs(const struct userstack_entry *entry, struct trace_seq *s,
		      unsigned long sym_flags)
{
	struct mm_struct *mm = NULL;
	int ret = 1;
	unsigned int i;

	if (trace_flags & TRACE_ITER_SYM_USEROBJ) {
		struct task_struct *task;
		/*
		 * we do the lookup on the thread group leader,
		 * since individual threads might have already quit!
		 */
		rcu_read_lock();
		task = find_task_by_vpid(entry->ent.tgid);
		if (task)
			mm = get_task_mm(task);
		rcu_read_unlock();
	}

	for (i = 0; i < FTRACE_STACK_ENTRIES; i++) {
		unsigned long ip = entry->caller[i];

		if (ip == ULONG_MAX || !ret)
			break;
		if (i && ret)
			ret = trace_seq_puts(s, " <- ");
		if (!ip) {
			if (ret)
				ret = trace_seq_puts(s, "??");
			continue;
		}
		if (!ret)
			break;
		if (ret)
			ret = seq_print_user_ip(s, mm, ip, sym_flags);
	}

	if (mm)
		mmput(mm);
	return ret;
}

int
seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags)
{
	int ret;

	if (!ip)
		return trace_seq_printf(s, "0");

	if (sym_flags & TRACE_ITER_SYM_OFFSET)
		ret = seq_print_sym_offset(s, "%s", ip);
	else
		ret = seq_print_sym_short(s, "%s", ip);

	if (!ret)
		return 0;

	if (sym_flags & TRACE_ITER_SYM_ADDR)
		ret = trace_seq_printf(s, " <" IP_FMT ">", ip);
	return ret;
}

static const char state_to_char[] = TASK_STATE_TO_CHAR_STR;

static int task_state_char(unsigned long state)
{
	int bit = state ? __ffs(state) + 1 : 0;

	return bit < sizeof(state_to_char) - 1 ? state_to_char[bit] : '?';
}

/**
 * ftrace_find_event - find a registered event
 * @type: the type of event to look for
 *
 * Returns an event of type @type otherwise NULL
 */
struct trace_event *ftrace_find_event(int type)
{
	struct trace_event *event;
	struct hlist_node *n;
	unsigned key;

	key = type & (EVENT_HASHSIZE - 1);

	hlist_for_each_entry_rcu(event, n, &event_hash[key], node) {
		if (event->type == type)
			return event;
	}

	return NULL;
}

/**
 * register_ftrace_event - register output for an event type
 * @event: the event type to register
 *
 * Event types are stored in a hash and this hash is used to
 * find a way to print an event. If the @event->type is set
 * then it will use that type, otherwise it will assign a
 * type to use.
 *
 * If you assign your own type, please make sure it is added
 * to the trace_type enum in trace.h, to avoid collisions
 * with the dynamic types.
 *
 * Returns the event type number or zero on error.
 */
int register_ftrace_event(struct trace_event *event)
{
	unsigned key;
	int ret = 0;

	mutex_lock(&trace_event_mutex);

	if (!event->type)
		event->type = next_event_type++;
	else if (event->type > __TRACE_LAST_TYPE) {
		printk(KERN_WARNING "Need to add type to trace.h\n");
		WARN_ON(1);
	}

	if (ftrace_find_event(event->type))
		goto out;

	key = event->type & (EVENT_HASHSIZE - 1);

	hlist_add_head_rcu(&event->node, &event_hash[key]);

	ret = event->type;
 out:
	mutex_unlock(&trace_event_mutex);

	return ret;
}

/**
 * unregister_ftrace_event - remove a no longer used event
 * @event: the event to remove
 */
int unregister_ftrace_event(struct trace_event *event)
{
	mutex_lock(&trace_event_mutex);
	hlist_del(&event->node);
	mutex_unlock(&trace_event_mutex);

	return 0;
}

/*
 * Standard events
 */

int
trace_nop_print(struct trace_seq *s, struct trace_entry *entry, int flags)
{
	return 0;
}

/* TRACE_FN */
static int
trace_fn_latency(struct trace_seq *s, struct trace_entry *entry, int flags)
{
	struct ftrace_entry *field;

	trace_assign_type(field, entry);

	if (!seq_print_ip_sym(s, field->ip, flags))
		goto partial;
	if (!trace_seq_puts(s, " ("))
		goto partial;
	if (!seq_print_ip_sym(s, field->parent_ip, flags))
		goto partial;
	if (!trace_seq_puts(s, ")\n"))
		goto partial;

	return 0;

 partial:
	return TRACE_TYPE_PARTIAL_LINE;
}

static int
trace_fn_trace(struct trace_seq *s, struct trace_entry *entry, int flags)
{
	struct ftrace_entry *field;

	trace_assign_type(field, entry);

	if (!seq_print_ip_sym(s, field->ip, flags))
		goto partial;

	if ((flags & TRACE_ITER_PRINT_PARENT) && field->parent_ip) {
		if (!trace_seq_printf(s, " <-"))
			goto partial;
		if (!seq_print_ip_sym(s,
				      field->parent_ip,
				      flags))
			goto partial;
	}
	if (!trace_seq_printf(s, "\n"))
		goto partial;

	return 0;

 partial:
	return TRACE_TYPE_PARTIAL_LINE;
}

static int
trace_fn_raw(struct trace_seq *s, struct trace_entry *entry, int flags)
{
	struct ftrace_entry *field;

	trace_assign_type(field, entry);

	if (!trace_seq_printf(s, "%x %x\n",
			      field->ip,
			      field->parent_ip))
		return TRACE_TYPE_PARTIAL_LINE;

	return 0;
}

static int
trace_fn_hex(struct trace_seq *s, struct trace_entry *entry, int flags)
{
	struct ftrace_entry *field;

	trace_assign_type(field, entry);

	SEQ_PUT_HEX_FIELD_RET(s, field->ip);
	SEQ_PUT_HEX_FIELD_RET(s, field->parent_ip);

	return 0;
}

static int
trace_fn_bin(struct trace_seq *s, struct trace_entry *entry, int flags)
{
	struct ftrace_entry *field;

	trace_assign_type(field, entry);

	SEQ_PUT_FIELD_RET(s, field->ip);
	SEQ_PUT_FIELD_RET(s, field->parent_ip);

	return 0;
}

static struct trace_event trace_fn_event = {
	.type	 	= TRACE_FN,
	.trace		= trace_fn_trace,
	.latency_trace	= trace_fn_latency,
	.raw		= trace_fn_raw,
	.hex		= trace_fn_hex,
	.binary		= trace_fn_bin,
};

/* TRACE_CTX an TRACE_WAKE */
static int
trace_ctxwake_print(struct trace_seq *s, struct trace_entry *entry, int flags,
		    char *delim)
{
	struct ctx_switch_entry *field;
	char *comm;
	int S, T;

	trace_assign_type(field, entry);

	T = task_state_char(field->next_state);
	S = task_state_char(field->prev_state);
	comm = trace_find_cmdline(field->next_pid);
	if (!trace_seq_printf(s, " %5d:%3d:%c %s [%03d] %5d:%3d:%c %s\n",
			      field->prev_pid,
			      field->prev_prio,
			      S, delim,
			      field->next_cpu,
			      field->next_pid,
			      field->next_prio,
			      T, comm))
		return TRACE_TYPE_PARTIAL_LINE;

	return 0;
}

static int
trace_ctx_print(struct trace_seq *s, struct trace_entry *entry, int flags)
{
	return trace_ctxwake_print(s, entry, flags, "==>");
}

static int
trace_wake_print(struct trace_seq *s, struct trace_entry *entry, int flags)
{
	return trace_ctxwake_print(s, entry, flags, "  +");
}

static int
trace_ctxwake_raw(struct trace_seq *s, struct trace_entry *entry, int flags,
		  char S)
{
	struct ctx_switch_entry *field;
	int T;

	trace_assign_type(field, entry);

	if (!S)
		task_state_char(field->prev_state);
	T = task_state_char(field->next_state);
	if (!trace_seq_printf(s, "%d %d %c %d %d %d %c\n",
			      field->prev_pid,
			      field->prev_prio,
			      S,
			      field->next_cpu,
			      field->next_pid,
			      field->next_prio,
			      T))
		return TRACE_TYPE_PARTIAL_LINE;

	return 0;
}

static int
trace_ctx_raw(struct trace_seq *s, struct trace_entry *entry, int flags)
{
	return trace_ctxwake_raw(s, entry, flags, 0);
}

static int
trace_wake_raw(struct trace_seq *s, struct trace_entry *entry, int flags)
{
	return trace_ctxwake_raw(s, entry, flags, '+');
}


static int
trace_ctxwake_hex(struct trace_seq *s, struct trace_entry *entry, int flags,
		  char S)
{
	struct ctx_switch_entry *field;
	int T;

	trace_assign_type(field, entry);

	if (!S)
		task_state_char(field->prev_state);
	T = task_state_char(field->next_state);

	SEQ_PUT_HEX_FIELD_RET(s, field->prev_pid);
	SEQ_PUT_HEX_FIELD_RET(s, field->prev_prio);
	SEQ_PUT_HEX_FIELD_RET(s, S);
	SEQ_PUT_HEX_FIELD_RET(s, field->next_cpu);
	SEQ_PUT_HEX_FIELD_RET(s, field->next_pid);
	SEQ_PUT_HEX_FIELD_RET(s, field->next_prio);
	SEQ_PUT_HEX_FIELD_RET(s, T);

	return 0;
}

static int
trace_ctx_hex(struct trace_seq *s, struct trace_entry *entry, int flags)
{
	return trace_ctxwake_hex(s, entry, flags, 0);
}

static int
trace_wake_hex(struct trace_seq *s, struct trace_entry *entry, int flags)
{
	return trace_ctxwake_hex(s, entry, flags, '+');
}

static int
trace_ctxwake_bin(struct trace_seq *s, struct trace_entry *entry, int flags)
{
	struct ctx_switch_entry *field;

	trace_assign_type(field, entry);

	SEQ_PUT_FIELD_RET(s, field->prev_pid);
	SEQ_PUT_FIELD_RET(s, field->prev_prio);
	SEQ_PUT_FIELD_RET(s, field->prev_state);
	SEQ_PUT_FIELD_RET(s, field->next_pid);
	SEQ_PUT_FIELD_RET(s, field->next_prio);
	SEQ_PUT_FIELD_RET(s, field->next_state);

	return 0;
}

static struct trace_event trace_ctx_event = {
	.type	 	= TRACE_CTX,
	.trace		= trace_ctx_print,
	.latency_trace	= trace_ctx_print,
	.raw		= trace_ctx_raw,
	.hex		= trace_ctx_hex,
	.binary		= trace_ctxwake_bin,
};

static struct trace_event trace_wake_event = {
	.type	 	= TRACE_WAKE,
	.trace		= trace_wake_print,
	.latency_trace	= trace_wake_print,
	.raw		= trace_wake_raw,
	.hex		= trace_wake_hex,
	.binary		= trace_ctxwake_bin,
};

/* TRACE_SPECIAL */
static int
trace_special_print(struct trace_seq *s, struct trace_entry *entry, int flags)
{
	struct special_entry *field;

	trace_assign_type(field, entry);

	if (!trace_seq_printf(s, "# %ld %ld %ld\n",
			      field->arg1,
			      field->arg2,
			      field->arg3))
		return TRACE_TYPE_PARTIAL_LINE;

	return 0;
}

static int
trace_special_hex(struct trace_seq *s, struct trace_entry *entry, int flags)
{
	struct special_entry *field;

	trace_assign_type(field, entry);

	SEQ_PUT_HEX_FIELD_RET(s, field->arg1);
	SEQ_PUT_HEX_FIELD_RET(s, field->arg2);
	SEQ_PUT_HEX_FIELD_RET(s, field->arg3);

	return 0;
}

static int
trace_special_bin(struct trace_seq *s, struct trace_entry *entry, int flags)
{
	struct special_entry *field;

	trace_assign_type(field, entry);

	SEQ_PUT_FIELD_RET(s, field->arg1);
	SEQ_PUT_FIELD_RET(s, field->arg2);
	SEQ_PUT_FIELD_RET(s, field->arg3);

	return 0;
}

static struct trace_event trace_special_event = {
	.type	 	= TRACE_SPECIAL,
	.trace		= trace_special_print,
	.latency_trace	= trace_special_print,
	.raw		= trace_special_print,
	.hex		= trace_special_hex,
	.binary		= trace_special_bin,
};

/* TRACE_STACK */

static int
trace_stack_print(struct trace_seq *s, struct trace_entry *entry, int flags)
{
	struct stack_entry *field;
	int i;

	trace_assign_type(field, entry);

	for (i = 0; i < FTRACE_STACK_ENTRIES; i++) {
		if (i) {
			if (!trace_seq_puts(s, " <= "))
				goto partial;

			if (!seq_print_ip_sym(s, field->caller[i], flags))
				goto partial;
		}
		if (!trace_seq_puts(s, "\n"))
			goto partial;
	}

	return 0;

 partial:
	return TRACE_TYPE_PARTIAL_LINE;
}

static struct trace_event trace_stack_event = {
	.type	 	= TRACE_STACK,
	.trace		= trace_stack_print,
	.latency_trace	= trace_stack_print,
	.raw		= trace_special_print,
	.hex		= trace_special_hex,
	.binary		= trace_special_bin,
};

/* TRACE_USER_STACK */
static int
trace_user_stack_print(struct trace_seq *s, struct trace_entry *entry,
		       int flags)
{
	struct userstack_entry *field;

	trace_assign_type(field, entry);

	if (!seq_print_userip_objs(field, s, flags))
		goto partial;

	if (!trace_seq_putc(s, '\n'))
		goto partial;

	return 0;

 partial:
	return TRACE_TYPE_PARTIAL_LINE;
}

static struct trace_event trace_user_stack_event = {
	.type	 	= TRACE_USER_STACK,
	.trace		= trace_user_stack_print,
	.latency_trace	= trace_user_stack_print,
	.raw		= trace_special_print,
	.hex		= trace_special_hex,
	.binary		= trace_special_bin,
};

/* TRACE_PRINT */
static int
trace_print_print(struct trace_seq *s, struct trace_entry *entry, int flags)
{
	struct print_entry *field;

	trace_assign_type(field, entry);

	if (!seq_print_ip_sym(s, field->ip, flags))
		goto partial;

	if (!trace_seq_printf(s, ": %s", field->buf))
		goto partial;

	return 0;

 partial:
	return TRACE_TYPE_PARTIAL_LINE;
}

static int
trace_print_raw(struct trace_seq *s, struct trace_entry *entry, int flags)
{
	struct print_entry *field;

	trace_assign_type(field, entry);

	if (!trace_seq_printf(s, "# %lx %s", field->ip, field->buf))
		goto partial;

	return 0;

 partial:
	return TRACE_TYPE_PARTIAL_LINE;
}

static struct trace_event trace_print_event = {
	.type	 	= TRACE_PRINT,
	.trace		= trace_print_print,
	.latency_trace	= trace_print_print,
	.raw		= trace_print_raw,
	.hex		= trace_nop_print,
	.binary		= trace_nop_print,
};

static struct trace_event *events[] __initdata = {
	&trace_fn_event,
	&trace_ctx_event,
	&trace_wake_event,
	&trace_special_event,
	&trace_stack_event,
	&trace_user_stack_event,
	&trace_print_event,
	NULL
};

__init static int init_events(void)
{
	struct trace_event *event;
	int i, ret;

	for (i = 0; events[i]; i++) {
		event = events[i];

		ret = register_ftrace_event(event);
		if (!ret) {
			printk(KERN_WARNING "event %d failed to register\n",
			       event->type);
			WARN_ON_ONCE(1);
		}
	}

	return 0;
}
device_initcall(init_events);
Commit	Line	Data
f0868d1e SR	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
	17	static DEFINE_MUTEX(trace_event_mutex);
	18	static struct hlist_head event_hash[EVENT_HASHSIZE] __read_mostly;
	19
	20	static int next_event_type = __TRACE_LAST_TYPE + 1;
	21
	22	/**
	23	* trace_seq_printf - sequence printing of trace information
	24	* @s: trace sequence descriptor
	25	* @fmt: printf format string
	26	*
	27	* The tracer may use either sequence operations or its own
	28	* copy to user routines. To simplify formating of a trace
	29	* trace_seq_printf is used to store strings into a special
	30	* buffer (@s). Then the output may be either used by
	31	* the sequencer or pulled into another buffer.
	32	*/
	33	int
	34	trace_seq_printf(struct trace_seq s, const char fmt, ...)
	35	{
	36	int len = (PAGE_SIZE - 1) - s->len;
	37	va_list ap;
	38	int ret;
	39
	40	if (!len)
	41	return 0;
	42
	43	va_start(ap, fmt);
	44	ret = vsnprintf(s->buffer + s->len, len, fmt, ap);
	45	va_end(ap);
	46
	47	/* If we can't write it all, don't bother writing anything */
	48	if (ret >= len)
	49	return 0;
	50
	51	s->len += ret;
	52
	53	return len;
	54	}
	55
	56	/**
	57	* trace_seq_puts - trace sequence printing of simple string
	58	* @s: trace sequence descriptor
	59	* @str: simple string to record
	60	*
	61	* The tracer may use either the sequence operations or its own
	62	* copy to user routines. This function records a simple string
	63	* into a special buffer (@s) for later retrieval by a sequencer
	64	* or other mechanism.
65	*/
66	int trace_seq_puts(struct trace_seq s, const char str)
67	{
68	int len = strlen(str);
69
70	if (len > ((PAGE_SIZE - 1) - s->len))
71	return 0;
72
73	memcpy(s->buffer + s->len, str, len);
74	s->len += len;
75
76	return len;
77	}
78
79	int trace_seq_putc(struct trace_seq *s, unsigned char c)
80	{
81	if (s->len >= (PAGE_SIZE - 1))
82	return 0;
83
84	s->buffer[s->len++] = c;
85
86	return 1;
87	}
88
89	int trace_seq_putmem(struct trace_seq s, void mem, size_t len)
90	{
91	if (len > ((PAGE_SIZE - 1) - s->len))
92	return 0;
93
94	memcpy(s->buffer + s->len, mem, len);
95	s->len += len;
96
97	return len;
98	}
99
100	int trace_seq_putmem_hex(struct trace_seq s, void mem, size_t len)
101	{
102	unsigned char hex[HEX_CHARS];
103	unsigned char *data = mem;
104	int i, j;
105
106	#ifdef __BIG_ENDIAN
107	for (i = 0, j = 0; i < len; i++) {
108	#else
109	for (i = len-1, j = 0; i >= 0; i--) {
110	#endif
111	hex[j++] = hex_asc_hi(data[i]);
112	hex[j++] = hex_asc_lo(data[i]);
113	}
114	hex[j++] = ' ';
115
116	return trace_seq_putmem(s, hex, j);
117	}
118
119	int trace_seq_path(struct trace_seq s, struct path path)
120	{
121	unsigned char *p;
122
123	if (s->len >= (PAGE_SIZE - 1))
124	return 0;
125	p = d_path(path, s->buffer + s->len, PAGE_SIZE - s->len);
126	if (!IS_ERR(p)) {
127	p = mangle_path(s->buffer + s->len, p, "\n");
128	if (p) {
129	s->len = p - s->buffer;
130	return 1;
131	}
132	} else {
133	s->buffer[s->len++] = '?';
134	return 1;
135	}
136
137	return 0;
138	}
139
140	#ifdef CONFIG_KRETPROBES
141	static inline const char kretprobed(const char name)
142	{
143	static const char tramp_name[] = "kretprobe_trampoline";
144	int size = sizeof(tramp_name);
145
146	if (strncmp(tramp_name, name, size) == 0)
147	return "[unknown/kretprobe'd]";
148	return name;
149	}
150	#else
151	static inline const char kretprobed(const char name)
152	{
153	return name;
154	}
155	#endif /* CONFIG_KRETPROBES */
156
157	static int
158	seq_print_sym_short(struct trace_seq s, const char fmt, unsigned long address)
159	{
160	#ifdef CONFIG_KALLSYMS
161	char str[KSYM_SYMBOL_LEN];
162	const char *name;
163
164	kallsyms_lookup(address, NULL, NULL, NULL, str);
165
166	name = kretprobed(str);
167
168	return trace_seq_printf(s, fmt, name);
169	#endif
170	return 1;
171	}
172
173	static int
174	seq_print_sym_offset(struct trace_seq s, const char fmt,
175	unsigned long address)
176	{
177	#ifdef CONFIG_KALLSYMS
178	char str[KSYM_SYMBOL_LEN];
179	const char *name;
180
181	sprint_symbol(str, address);
182	name = kretprobed(str);
183
184	return trace_seq_printf(s, fmt, name);
185	#endif
186	return 1;
187	}
188
189	#ifndef CONFIG_64BIT
190	# define IP_FMT "%08lx"
191	#else
192	# define IP_FMT "%016lx"
193	#endif
194
195	int seq_print_user_ip(struct trace_seq s, struct mm_struct mm,
196	unsigned long ip, unsigned long sym_flags)
197	{
198	struct file *file = NULL;
199	unsigned long vmstart = 0;
200	int ret = 1;
201
202	if (mm) {
203	const struct vm_area_struct *vma;
204
205	down_read(&mm->mmap_sem);
206	vma = find_vma(mm, ip);
207	if (vma) {
208	file = vma->vm_file;
209	vmstart = vma->vm_start;
210	}
211	if (file) {
212	ret = trace_seq_path(s, &file->f_path);
213	if (ret)
214	ret = trace_seq_printf(s, "[+0x%lx]",
215	ip - vmstart);
216	}
217	up_read(&mm->mmap_sem);
218	}
219	if (ret && ((sym_flags & TRACE_ITER_SYM_ADDR) \|\| !file))
220	ret = trace_seq_printf(s, " <" IP_FMT ">", ip);
221	return ret;
222	}
223
224	int
225	seq_print_userip_objs(const struct userstack_entry entry, struct trace_seq s,
226	unsigned long sym_flags)
227	{
228	struct mm_struct *mm = NULL;
229	int ret = 1;
230	unsigned int i;
231
232	if (trace_flags & TRACE_ITER_SYM_USEROBJ) {
233	struct task_struct *task;
234	/*
235	* we do the lookup on the thread group leader,
236	* since individual threads might have already quit!
237	*/
238	rcu_read_lock();
239	task = find_task_by_vpid(entry->ent.tgid);
240	if (task)
241	mm = get_task_mm(task);
242	rcu_read_unlock();
243	}
244
245	for (i = 0; i < FTRACE_STACK_ENTRIES; i++) {
246	unsigned long ip = entry->caller[i];
247
248	if (ip == ULONG_MAX \|\| !ret)
249	break;
250	if (i && ret)
251	ret = trace_seq_puts(s, " <- ");
252	if (!ip) {
253	if (ret)
254	ret = trace_seq_puts(s, "??");
255	continue;
256	}
257	if (!ret)
258	break;
259	if (ret)
260	ret = seq_print_user_ip(s, mm, ip, sym_flags);
261	}
262
263	if (mm)
264	mmput(mm);
265	return ret;
266	}
267
268	int
269	seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags)
270	{
271	int ret;
272
273	if (!ip)
274	return trace_seq_printf(s, "0");
275
276	if (sym_flags & TRACE_ITER_SYM_OFFSET)
277	ret = seq_print_sym_offset(s, "%s", ip);
278	else
279	ret = seq_print_sym_short(s, "%s", ip);
280
281	if (!ret)
282	return 0;
283
284	if (sym_flags & TRACE_ITER_SYM_ADDR)
285	ret = trace_seq_printf(s, " <" IP_FMT ">", ip);
286	return ret;
287	}
288
f633cef0 SR	289	static const char state_to_char[] = TASK_STATE_TO_CHAR_STR;
	290
	291	static int task_state_char(unsigned long state)
	292	{
	293	int bit = state ? __ffs(state) + 1 : 0;
	294
	295	return bit < sizeof(state_to_char) - 1 ? state_to_char[bit] : '?';
	296	}
	297
f0868d1e SR	298	/**
	299	* ftrace_find_event - find a registered event
	300	* @type: the type of event to look for
	301	*
	302	* Returns an event of type @type otherwise NULL
	303	*/
	304	struct trace_event *ftrace_find_event(int type)
	305	{
	306	struct trace_event *event;
	307	struct hlist_node *n;
	308	unsigned key;
	309
	310	key = type & (EVENT_HASHSIZE - 1);
	311
	312	hlist_for_each_entry_rcu(event, n, &event_hash[key], node) {
	313	if (event->type == type)
	314	return event;
	315	}
	316
	317	return NULL;
	318	}
	319
	320	/**
	321	* register_ftrace_event - register output for an event type
	322	* @event: the event type to register
	323	*
	324	* Event types are stored in a hash and this hash is used to
	325	* find a way to print an event. If the @event->type is set
	326	* then it will use that type, otherwise it will assign a
	327	* type to use.
	328	*
	329	* If you assign your own type, please make sure it is added
	330	* to the trace_type enum in trace.h, to avoid collisions
	331	* with the dynamic types.
	332	*
	333	* Returns the event type number or zero on error.
	334	*/
	335	int register_ftrace_event(struct trace_event *event)
	336	{
	337	unsigned key;
	338	int ret = 0;
	339
	340	mutex_lock(&trace_event_mutex);
	341
	342	if (!event->type)
	343	event->type = next_event_type++;
	344	else if (event->type > __TRACE_LAST_TYPE) {
	345	printk(KERN_WARNING "Need to add type to trace.h\n");
	346	WARN_ON(1);
	347	}
	348
	349	if (ftrace_find_event(event->type))
	350	goto out;
	351
	352	key = event->type & (EVENT_HASHSIZE - 1);
	353
	354	hlist_add_head_rcu(&event->node, &event_hash[key]);
	355
	356	ret = event->type;
	357	out:
	358	mutex_unlock(&trace_event_mutex);
	359
	360	return ret;
	361	}
362
363	/**
364	* unregister_ftrace_event - remove a no longer used event
365	* @event: the event to remove
366	*/
367	int unregister_ftrace_event(struct trace_event *event)
368	{
369	mutex_lock(&trace_event_mutex);
370	hlist_del(&event->node);
371	mutex_unlock(&trace_event_mutex);
372
373	return 0;
374	}
f633cef0 SR	375
	376	/*
	377	* Standard events
	378	*/
	379
	380	int
	381	trace_nop_print(struct trace_seq s, struct trace_entry entry, int flags)
	382	{
	383	return 0;
	384	}
	385
	386	/* TRACE_FN */
	387	static int
	388	trace_fn_latency(struct trace_seq s, struct trace_entry entry, int flags)
	389	{
	390	struct ftrace_entry *field;
	391
	392	trace_assign_type(field, entry);
	393
	394	if (!seq_print_ip_sym(s, field->ip, flags))
	395	goto partial;
	396	if (!trace_seq_puts(s, " ("))
	397	goto partial;
	398	if (!seq_print_ip_sym(s, field->parent_ip, flags))
	399	goto partial;
	400	if (!trace_seq_puts(s, ")\n"))
	401	goto partial;
	402
	403	return 0;
	404
	405	partial:
	406	return TRACE_TYPE_PARTIAL_LINE;
	407	}
	408
	409	static int
	410	trace_fn_trace(struct trace_seq s, struct trace_entry entry, int flags)
	411	{
	412	struct ftrace_entry *field;
	413
	414	trace_assign_type(field, entry);
	415
	416	if (!seq_print_ip_sym(s, field->ip, flags))
	417	goto partial;
	418
	419	if ((flags & TRACE_ITER_PRINT_PARENT) && field->parent_ip) {
	420	if (!trace_seq_printf(s, " <-"))
	421	goto partial;
	422	if (!seq_print_ip_sym(s,
	423	field->parent_ip,
	424	flags))
	425	goto partial;
	426	}
	427	if (!trace_seq_printf(s, "\n"))
	428	goto partial;
	429
	430	return 0;
	431
	432	partial:
	433	return TRACE_TYPE_PARTIAL_LINE;
	434	}
	435
	436	static int
	437	trace_fn_raw(struct trace_seq s, struct trace_entry entry, int flags)
	438	{
439	struct ftrace_entry *field;
440
441	trace_assign_type(field, entry);
442
6c1a99af LJ	443	if (!trace_seq_printf(s, "%x %x\n",
	444	field->ip,
	445	field->parent_ip))
f633cef0 SR	446	return TRACE_TYPE_PARTIAL_LINE;
	447
	448	return 0;
	449	}
	450
	451	static int
	452	trace_fn_hex(struct trace_seq s, struct trace_entry entry, int flags)
	453	{
	454	struct ftrace_entry *field;
	455
	456	trace_assign_type(field, entry);
	457
	458	SEQ_PUT_HEX_FIELD_RET(s, field->ip);
	459	SEQ_PUT_HEX_FIELD_RET(s, field->parent_ip);
	460
	461	return 0;
	462	}
	463
	464	static int
	465	trace_fn_bin(struct trace_seq s, struct trace_entry entry, int flags)
	466	{
	467	struct ftrace_entry *field;
	468
	469	trace_assign_type(field, entry);
	470
	471	SEQ_PUT_FIELD_RET(s, field->ip);
	472	SEQ_PUT_FIELD_RET(s, field->parent_ip);
	473
	474	return 0;
	475	}
	476
	477	static struct trace_event trace_fn_event = {
	478	.type = TRACE_FN,
	479	.trace = trace_fn_trace,
	480	.latency_trace = trace_fn_latency,
	481	.raw = trace_fn_raw,
	482	.hex = trace_fn_hex,
	483	.binary = trace_fn_bin,
	484	};
	485
	486	/* TRACE_CTX an TRACE_WAKE */
	487	static int
	488	trace_ctxwake_print(struct trace_seq s, struct trace_entry entry, int flags,
	489	char *delim)
	490	{
	491	struct ctx_switch_entry *field;
	492	char *comm;
	493	int S, T;
	494
	495	trace_assign_type(field, entry);
	496
	497	T = task_state_char(field->next_state);
	498	S = task_state_char(field->prev_state);
	499	comm = trace_find_cmdline(field->next_pid);
6c1a99af LJ	500	if (!trace_seq_printf(s, " %5d:%3d:%c %s [%03d] %5d:%3d:%c %s\n",
	501	field->prev_pid,
	502	field->prev_prio,
	503	S, delim,
	504	field->next_cpu,
	505	field->next_pid,
	506	field->next_prio,
	507	T, comm))
f633cef0 SR	508	return TRACE_TYPE_PARTIAL_LINE;
	509
	510	return 0;
	511	}
	512
	513	static int
	514	trace_ctx_print(struct trace_seq s, struct trace_entry entry, int flags)
	515	{
	516	return trace_ctxwake_print(s, entry, flags, "==>");
	517	}
	518
	519	static int
	520	trace_wake_print(struct trace_seq s, struct trace_entry entry, int flags)
	521	{
	522	return trace_ctxwake_print(s, entry, flags, " +");
	523	}
	524
	525	static int
	526	trace_ctxwake_raw(struct trace_seq s, struct trace_entry entry, int flags,
	527	char S)
	528	{
	529	struct ctx_switch_entry *field;
	530	int T;
	531
	532	trace_assign_type(field, entry);
	533
	534	if (!S)
	535	task_state_char(field->prev_state);
	536	T = task_state_char(field->next_state);
6c1a99af LJ	537	if (!trace_seq_printf(s, "%d %d %c %d %d %d %c\n",
	538	field->prev_pid,
	539	field->prev_prio,
	540	S,
	541	field->next_cpu,
	542	field->next_pid,
	543	field->next_prio,
	544	T))
f633cef0 SR	545	return TRACE_TYPE_PARTIAL_LINE;
	546
	547	return 0;
	548	}
	549
	550	static int
	551	trace_ctx_raw(struct trace_seq s, struct trace_entry entry, int flags)
	552	{
	553	return trace_ctxwake_raw(s, entry, flags, 0);
	554	}
	555
	556	static int
	557	trace_wake_raw(struct trace_seq s, struct trace_entry entry, int flags)
	558	{
	559	return trace_ctxwake_raw(s, entry, flags, '+');
	560	}
	561
	562
	563	static int
	564	trace_ctxwake_hex(struct trace_seq s, struct trace_entry entry, int flags,
	565	char S)
	566	{
	567	struct ctx_switch_entry *field;
	568	int T;
	569
	570	trace_assign_type(field, entry);
	571
	572	if (!S)
	573	task_state_char(field->prev_state);
	574	T = task_state_char(field->next_state);
	575
	576	SEQ_PUT_HEX_FIELD_RET(s, field->prev_pid);
	577	SEQ_PUT_HEX_FIELD_RET(s, field->prev_prio);
	578	SEQ_PUT_HEX_FIELD_RET(s, S);
	579	SEQ_PUT_HEX_FIELD_RET(s, field->next_cpu);
	580	SEQ_PUT_HEX_FIELD_RET(s, field->next_pid);
	581	SEQ_PUT_HEX_FIELD_RET(s, field->next_prio);
	582	SEQ_PUT_HEX_FIELD_RET(s, T);
	583
	584	return 0;
	585	}
	586
	587	static int
	588	trace_ctx_hex(struct trace_seq s, struct trace_entry entry, int flags)
	589	{
	590	return trace_ctxwake_hex(s, entry, flags, 0);
	591	}
	592
	593	static int
	594	trace_wake_hex(struct trace_seq s, struct trace_entry entry, int flags)
	595	{
	596	return trace_ctxwake_hex(s, entry, flags, '+');
	597	}
	598
	599	static int
	600	trace_ctxwake_bin(struct trace_seq s, struct trace_entry entry, int flags)
	601	{
	602	struct ctx_switch_entry *field;
	603
	604	trace_assign_type(field, entry);
	605
	606	SEQ_PUT_FIELD_RET(s, field->prev_pid);
	607	SEQ_PUT_FIELD_RET(s, field->prev_prio);
	608	SEQ_PUT_FIELD_RET(s, field->prev_state);
609	SEQ_PUT_FIELD_RET(s, field->next_pid);
610	SEQ_PUT_FIELD_RET(s, field->next_prio);
611	SEQ_PUT_FIELD_RET(s, field->next_state);
612
613	return 0;
614	}
615
616	static struct trace_event trace_ctx_event = {
617	.type = TRACE_CTX,
618	.trace = trace_ctx_print,
619	.latency_trace = trace_ctx_print,
620	.raw = trace_ctx_raw,
621	.hex = trace_ctx_hex,
622	.binary = trace_ctxwake_bin,
623	};
624
625	static struct trace_event trace_wake_event = {
626	.type = TRACE_WAKE,
627	.trace = trace_wake_print,
628	.latency_trace = trace_wake_print,
629	.raw = trace_wake_raw,
630	.hex = trace_wake_hex,
631	.binary = trace_ctxwake_bin,
632	};
633
634	/* TRACE_SPECIAL */
635	static int
636	trace_special_print(struct trace_seq s, struct trace_entry entry, int flags)
637	{
638	struct special_entry *field;
639
640	trace_assign_type(field, entry);
641
6c1a99af LJ	642	if (!trace_seq_printf(s, "# %ld %ld %ld\n",
	643	field->arg1,
	644	field->arg2,
	645	field->arg3))
f633cef0 SR	646	return TRACE_TYPE_PARTIAL_LINE;
	647
	648	return 0;
	649	}
	650
	651	static int
	652	trace_special_hex(struct trace_seq s, struct trace_entry entry, int flags)
	653	{
	654	struct special_entry *field;
	655
	656	trace_assign_type(field, entry);
	657
	658	SEQ_PUT_HEX_FIELD_RET(s, field->arg1);
	659	SEQ_PUT_HEX_FIELD_RET(s, field->arg2);
	660	SEQ_PUT_HEX_FIELD_RET(s, field->arg3);
	661
	662	return 0;
	663	}
	664
	665	static int
	666	trace_special_bin(struct trace_seq s, struct trace_entry entry, int flags)
	667	{
	668	struct special_entry *field;
	669
	670	trace_assign_type(field, entry);
	671
	672	SEQ_PUT_FIELD_RET(s, field->arg1);
	673	SEQ_PUT_FIELD_RET(s, field->arg2);
	674	SEQ_PUT_FIELD_RET(s, field->arg3);
	675
	676	return 0;
	677	}
	678
	679	static struct trace_event trace_special_event = {
	680	.type = TRACE_SPECIAL,
	681	.trace = trace_special_print,
	682	.latency_trace = trace_special_print,
	683	.raw = trace_special_print,
	684	.hex = trace_special_hex,
	685	.binary = trace_special_bin,
	686	};
	687
	688	/* TRACE_STACK */
	689
	690	static int
	691	trace_stack_print(struct trace_seq s, struct trace_entry entry, int flags)
	692	{
	693	struct stack_entry *field;
	694	int i;
	695
	696	trace_assign_type(field, entry);
	697
	698	for (i = 0; i < FTRACE_STACK_ENTRIES; i++) {
	699	if (i) {
6c1a99af	700	if (!trace_seq_puts(s, " <= "))
f633cef0 SR	701	goto partial;
f633cef0 SR	702
6c1a99af	703	if (!seq_print_ip_sym(s, field->caller[i], flags))
f633cef0 SR	704	goto partial;
f633cef0 SR	705	}
6c1a99af	706	if (!trace_seq_puts(s, "\n"))
f633cef0 SR	707	goto partial;
	708	}
	709
	710	return 0;
	711
	712	partial:
	713	return TRACE_TYPE_PARTIAL_LINE;
	714	}
	715
	716	static struct trace_event trace_stack_event = {
	717	.type = TRACE_STACK,
	718	.trace = trace_stack_print,
	719	.latency_trace = trace_stack_print,
	720	.raw = trace_special_print,
	721	.hex = trace_special_hex,
	722	.binary = trace_special_bin,
	723	};
	724
	725	/* TRACE_USER_STACK */
	726	static int
	727	trace_user_stack_print(struct trace_seq s, struct trace_entry entry,
	728	int flags)
	729	{
	730	struct userstack_entry *field;
	731
	732	trace_assign_type(field, entry);
	733
6c1a99af	734	if (!seq_print_userip_objs(field, s, flags))
f633cef0 SR	735	goto partial;
f633cef0 SR	736
6c1a99af	737	if (!trace_seq_putc(s, '\n'))
f633cef0 SR	738	goto partial;
	739
	740	return 0;
	741
	742	partial:
	743	return TRACE_TYPE_PARTIAL_LINE;
	744	}
	745
	746	static struct trace_event trace_user_stack_event = {
	747	.type = TRACE_USER_STACK,
	748	.trace = trace_user_stack_print,
	749	.latency_trace = trace_user_stack_print,
	750	.raw = trace_special_print,
	751	.hex = trace_special_hex,
	752	.binary = trace_special_bin,
	753	};
	754
	755	/* TRACE_PRINT */
	756	static int
	757	trace_print_print(struct trace_seq s, struct trace_entry entry, int flags)
	758	{
	759	struct print_entry *field;
	760
	761	trace_assign_type(field, entry);
	762
6c1a99af	763	if (!seq_print_ip_sym(s, field->ip, flags))
f633cef0 SR	764	goto partial;
f633cef0 SR	765
6c1a99af	766	if (!trace_seq_printf(s, ": %s", field->buf))
f633cef0 SR	767	goto partial;
	768
	769	return 0;
	770
	771	partial:
	772	return TRACE_TYPE_PARTIAL_LINE;
	773	}
	774
	775	static int
	776	trace_print_raw(struct trace_seq s, struct trace_entry entry, int flags)
	777	{
	778	struct print_entry *field;
	779
	780	trace_assign_type(field, entry);
	781
6c1a99af	782	if (!trace_seq_printf(s, "# %lx %s", field->ip, field->buf))
f633cef0 SR	783	goto partial;
	784
	785	return 0;
	786
	787	partial:
	788	return TRACE_TYPE_PARTIAL_LINE;
	789	}
	790
	791	static struct trace_event trace_print_event = {
	792	.type = TRACE_PRINT,
	793	.trace = trace_print_print,
	794	.latency_trace = trace_print_print,
	795	.raw = trace_print_raw,
	796	.hex = trace_nop_print,
	797	.binary = trace_nop_print,
	798	};
	799
	800	static struct trace_event *events[] __initdata = {
	801	&trace_fn_event,
	802	&trace_ctx_event,
	803	&trace_wake_event,
	804	&trace_special_event,
	805	&trace_stack_event,
	806	&trace_user_stack_event,
	807	&trace_print_event,
	808	NULL
	809	};
	810
	811	__init static int init_events(void)
	812	{
	813	struct trace_event *event;
	814	int i, ret;
	815
	816	for (i = 0; events[i]; i++) {
	817	event = events[i];
	818
	819	ret = register_ftrace_event(event);
	820	if (!ret) {
	821	printk(KERN_WARNING "event %d failed to register\n",
	822	event->type);
	823	WARN_ON_ONCE(1);
	824	}
	825	}
	826
	827	return 0;
	828	}
	829	device_initcall(init_events);