path: root/kernel/trace/trace_output.c

// SPDX-License-Identifier: GPL-2.0
/*
 * 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 <linux/kprobes.h>
#include <linux/sched/clock.h>
#include <linux/sched/mm.h>

#include "trace_output.h"

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

DECLARE_RWSEM(trace_event_sem);

static struct hlist_head event_hash[EVENT_HASHSIZE] __read_mostly;

static int next_event_type = __TRACE_LAST_TYPE;

enum print_line_t trace_print_bputs_msg_only(struct trace_iterator *iter)
{
	struct trace_seq *s = &iter->seq;
	struct trace_entry *entry = iter->ent;
	struct bputs_entry *field;

	trace_assign_type(field, entry);

	trace_seq_puts(s, field->str);

	return trace_handle_return(s);
}

enum print_line_t trace_print_bprintk_msg_only(struct trace_iterator *iter)
{
	struct trace_seq *s = &iter->seq;
	struct trace_entry *entry = iter->ent;
	struct bprint_entry *field;

	trace_assign_type(field, entry);

	trace_seq_bprintf(s, field->fmt, field->buf);

	return trace_handle_return(s);
}

enum print_line_t trace_print_printk_msg_only(struct trace_iterator *iter)
{
	struct trace_seq *s = &iter->seq;
	struct trace_entry *entry = iter->ent;
	struct print_entry *field;

	trace_assign_type(field, entry);

	trace_seq_puts(s, field->buf);

	return trace_handle_return(s);
}

const char *
trace_print_flags_seq(struct trace_seq *p, const char *delim,
		      unsigned long flags,
		      const struct trace_print_flags *flag_array)
{
	unsigned long mask;
	const char *str;
	const char *ret = trace_seq_buffer_ptr(p);
	int i, first = 1;

	for (i = 0;  flag_array[i].name && flags; i++) {

		mask = flag_array[i].mask;
		if ((flags & mask) != mask)
			continue;

		str = flag_array[i].name;
		flags &= ~mask;
		if (!first && delim)
			trace_seq_puts(p, delim);
		else
			first = 0;
		trace_seq_puts(p, str);
	}

	/* check for left over flags */
	if (flags) {
		if (!first && delim)
			trace_seq_puts(p, delim);
		trace_seq_printf(p, "0x%lx", flags);
	}

	trace_seq_putc(p, 0);

	return ret;
}
EXPORT_SYMBOL(trace_print_flags_seq);

const char *
trace_print_symbols_seq(struct trace_seq *p, unsigned long val,
			const struct trace_print_flags *symbol_array)
{
	int i;
	const char *ret = trace_seq_buffer_ptr(p);

	for (i = 0;  symbol_array[i].name; i++) {

		if (val != symbol_array[i].mask)
			continue;

		trace_seq_puts(p, symbol_array[i].name);
		break;
	}

	if (ret == (const char *)(trace_seq_buffer_ptr(p)))
		trace_seq_printf(p, "0x%lx", val);

	trace_seq_putc(p, 0);

	return ret;
}
EXPORT_SYMBOL(trace_print_symbols_seq);

#if BITS_PER_LONG == 32
const char *
trace_print_flags_seq_u64(struct trace_seq *p, const char *delim,
		      unsigned long long flags,
		      const struct trace_print_flags_u64 *flag_array)
{
	unsigned long long mask;
	const char *str;
	const char *ret = trace_seq_buffer_ptr(p);
	int i, first = 1;

	for (i = 0;  flag_array[i].name && flags; i++) {

		mask = flag_array[i].mask;
		if ((flags & mask) != mask)
			continue;

		str = flag_array[i].name;
		flags &= ~mask;
		if (!first && delim)
			trace_seq_puts(p, delim);
		else
			first = 0;
		trace_seq_puts(p, str);
	}

	/* check for left over flags */
	if (flags) {
		if (!first && delim)
			trace_seq_puts(p, delim);
		trace_seq_printf(p, "0x%llx", flags);
	}

	trace_seq_putc(p, 0);

	return ret;
}
EXPORT_SYMBOL(trace_print_flags_seq_u64);

const char *
trace_print_symbols_seq_u64(struct trace_seq *p, unsigned long long val,
			 const struct trace_print_flags_u64 *symbol_array)
{
	int i;
	const char *ret = trace_seq_buffer_ptr(p);

	for (i = 0;  symbol_array[i].name; i++) {

		if (val != symbol_array[i].mask)
			continue;

		trace_seq_puts(p, symbol_array[i].name);
		break;
	}

	if (ret == (const char *)(trace_seq_buffer_ptr(p)))
		trace_seq_printf(p, "0x%llx", val);

	trace_seq_putc(p, 0);

	return ret;
}
EXPORT_SYMBOL(trace_print_symbols_seq_u64);
#endif

const char *
trace_print_bitmask_seq(struct trace_seq *p, void *bitmask_ptr,
			unsigned int bitmask_size)
{
	const char *ret = trace_seq_buffer_ptr(p);

	trace_seq_bitmask(p, bitmask_ptr, bitmask_size * 8);
	trace_seq_putc(p, 0);

	return ret;
}
EXPORT_SYMBOL_GPL(trace_print_bitmask_seq);

/**
 * trace_print_hex_seq - print buffer as hex sequence
 * @p: trace seq struct to write to
 * @buf: The buffer to print
 * @buf_len: Length of @buf in bytes
 * @concatenate: Print @buf as single hex string or with spacing
 *
 * Prints the passed buffer as a hex sequence either as a whole,
 * single hex string if @concatenate is true or with spacing after
 * each byte in case @concatenate is false.
 */
const char *
trace_print_hex_seq(struct trace_seq *p, const unsigned char *buf, int buf_len,
		    bool concatenate)
{
	int i;
	const char *ret = trace_seq_buffer_ptr(p);
	const char *fmt = concatenate ? "%*phN" : "%*ph";

	for (i = 0; i < buf_len; i += 16)
		trace_seq_printf(p, fmt, min(buf_len - i, 16), &buf[i]);
	trace_seq_putc(p, 0);

	return ret;
}
EXPORT_SYMBOL(trace_print_hex_seq);

const char *
trace_print_array_seq(struct trace_seq *p, const void *buf, int count,
		      size_t el_size)
{
	const char *ret = trace_seq_buffer_ptr(p);
	const char *prefix = "";
	void *ptr = (void *)buf;
	size_t buf_len = count * el_size;

	trace_seq_putc(p, '{');

	while (ptr < buf + buf_len) {
		switch (el_size) {
		case 1:
			trace_seq_printf(p, "%s0x%x", prefix,
					 *(u8 *)ptr);
			break;
		case 2:
			trace_seq_printf(p, "%s0x%x", prefix,
					 *(u16 *)ptr);
			break;
		case 4:
			trace_seq_printf(p, "%s0x%x", prefix,
					 *(u32 *)ptr);
			break;
		case 8:
			trace_seq_printf(p, "%s0x%llx", prefix,
					 *(u64 *)ptr);
			break;
		default:
			trace_seq_printf(p, "BAD SIZE:%zu 0x%x", el_size,
					 *(u8 *)ptr);
			el_size = 1;
		}
		prefix = ",";
		ptr += el_size;
	}

	trace_seq_putc(p, '}');
	trace_seq_putc