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trace_output.c
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// 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 <linux/idr.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;
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) {
if (!concatenate && i != 0)
trace_seq_putc(p, ' ');
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(p, 0);
return ret;
}
EXPORT_SYMBOL(trace_print_array_seq);
const char *
trace_print_hex_dump_seq(struct trace_seq *p, const char *prefix_str,
int prefix_type, int rowsize, int groupsize,
const void *buf, size_t len, bool ascii)
{
const char *ret = trace_seq_buffer_ptr(p);
trace_seq_putc(p, '\n');
trace_seq_hex_dump(p, prefix_str, prefix_type,
rowsize, groupsize, buf, len, ascii);
trace_seq_putc(p, 0);
return ret;
}
EXPORT_SYMBOL(trace_print_hex_dump_seq);
int trace_raw_output_prep(struct trace_iterator *iter,
struct trace_event *trace_event)
{
struct trace_event_call *event;
struct trace_seq *s = &iter->seq;
struct trace_seq *p = &iter->tmp_seq;
struct trace_entry *entry;
event = container_of(trace_event, struct trace_event_call, event);
entry = iter->ent;
if (entry->type != event->event.type) {
WARN_ON_ONCE(1);
return TRACE_TYPE_UNHANDLED;
}
trace_seq_init(p);
trace_seq_printf(s, "%s: ", trace_event_name(event));
return trace_handle_return(s);
}
EXPORT_SYMBOL(trace_raw_output_prep);
void trace_event_printf(struct trace_iterator *iter, const char *fmt, ...)
{
struct trace_seq *s = &iter->seq;
va_list ap;
if (ignore_event(iter))
return;
va_start(ap, fmt);
trace_seq_vprintf(s, trace_event_format(iter, fmt), ap);
va_end(ap);
}
EXPORT_SYMBOL(trace_event_printf);
static __printf(3, 0)
int trace_output_raw(struct trace_iterator *iter, char *name,
char *fmt, va_list ap)
{
struct trace_seq *s = &iter->seq;
trace_seq_printf(s, "%s: ", name);
trace_seq_vprintf(s, trace_event_format(iter, fmt), ap);
return trace_handle_return(s);
}
int trace_output_call(struct trace_iterator *iter, char *name, char *fmt, ...)
{
va_list ap;
int ret;
va_start(ap, fmt);
ret = trace_output_raw(iter, name, fmt, ap);
va_end(ap);
return ret;
}
EXPORT_SYMBOL_GPL(trace_output_call);
static inline const char *kretprobed(const char *name, unsigned long addr)
{
if (is_kretprobe_trampoline(addr))
return "[unknown/kretprobe'd]";
return name;
}
void
trace_seq_print_sym(struct trace_seq *s, unsigned long address, bool offset)
{
#ifdef CONFIG_KALLSYMS
char str[KSYM_SYMBOL_LEN];
const char *name;
if (offset)
sprint_symbol(str, address);
else
kallsyms_lookup(address, NULL, NULL, NULL, str);
name = kretprobed(str, address);
if (name && strlen(name)) {
trace_seq_puts(s, name);
return;
}
#endif
trace_seq_printf(s, "0x%08lx", address);
}
#ifndef CONFIG_64BIT
# define IP_FMT "%08lx"
#else
# define IP_FMT "%016lx"
#endif
static 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 (s->full)
return 0;
if (mm) {
const struct vm_area_struct *vma;
mmap_read_lock(mm);
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)
trace_seq_printf(s, "[+0x%lx]",
ip - vmstart);
}
mmap_read_unlock(mm);
}
if (ret && ((sym_flags & TRACE_ITER_SYM_ADDR) || !file))
trace_seq_printf(s, " <" IP_FMT ">", ip);
return !trace_seq_has_overflowed(s);
}
int
seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags)
{
if (!ip) {
trace_seq_putc(s, '0');
goto out;
}
trace_seq_print_sym(s, ip, sym_flags & TRACE_ITER_SYM_OFFSET);
if (sym_flags & TRACE_ITER_SYM_ADDR)
trace_seq_printf(s, " <" IP_FMT ">", ip);
out:
return !trace_seq_has_overflowed(s);
}
/**
* trace_print_lat_fmt - print the irq, preempt and lockdep fields
* @s: trace seq struct to write to
* @entry: The trace entry field from the ring buffer
*
* Prints the generic fields of irqs off, in hard or softirq, preempt
* count.
*/
int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
{
char hardsoft_irq;
char need_resched;
char irqs_off;
int hardirq;
int softirq;
int bh_off;
int nmi;
nmi = entry->flags & TRACE_FLAG_NMI;
hardirq = entry->flags & TRACE_FLAG_HARDIRQ;
softirq = entry->flags & TRACE_FLAG_SOFTIRQ;
bh_off = entry->flags & TRACE_FLAG_BH_OFF;
irqs_off =
(entry->flags & TRACE_FLAG_IRQS_OFF && bh_off) ? 'D' :
(entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' :
bh_off ? 'b' :
(entry->flags & TRACE_FLAG_IRQS_NOSUPPORT) ? 'X' :
'.';
switch (entry->flags & (TRACE_FLAG_NEED_RESCHED |
TRACE_FLAG_PREEMPT_RESCHED)) {
case TRACE_FLAG_NEED_RESCHED | TRACE_FLAG_PREEMPT_RESCHED:
need_resched = 'N';
break;
case TRACE_FLAG_NEED_RESCHED:
need_resched = 'n';
break;
case TRACE_FLAG_PREEMPT_RESCHED:
need_resched = 'p';
break;
default:
need_resched = '.';
break;
}
hardsoft_irq =
(nmi && hardirq) ? 'Z' :
nmi ? 'z' :
(hardirq && softirq) ? 'H' :
hardirq ? 'h' :
softirq ? 's' :
'.' ;
trace_seq_printf(s, "%c%c%c",
irqs_off, need_resched, hardsoft_irq);
if (entry->preempt_count & 0xf)
trace_seq_printf(s, "%x", entry->preempt_count & 0xf);
else
trace_seq_putc(s, '.');
if (entry->preempt_count & 0xf0)
trace_seq_printf(s, "%x", entry->preempt_count >> 4);
else
trace_seq_putc(s, '.');
return !trace_seq_has_overflowed(s);
}
static int
lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu)
{
char comm[TASK_COMM_LEN];
trace_find_cmdline(entry->pid, comm);
trace_seq_printf(s, "%8.8s-%-7d %3d",
comm, entry->pid, cpu);
return trace_print_lat_fmt(s, entry);
}
#undef MARK
#define MARK(v, s) {.val = v, .sym = s}
/* trace overhead mark */
static const struct trace_mark {
unsigned long long val; /* unit: nsec */
char sym;
} mark[] = {
MARK(1000000000ULL , '$'), /* 1 sec */
MARK(100000000ULL , '@'), /* 100 msec */
MARK(10000000ULL , '*'), /* 10 msec */
MARK(1000000ULL , '#'), /* 1000 usecs */
MARK(100000ULL , '!'), /* 100 usecs */
MARK(10000ULL , '+'), /* 10 usecs */
};
#undef MARK
char trace_find_mark(unsigned long long d)
{
int i;
int size = ARRAY_SIZE(mark);
for (i = 0; i < size; i++) {
if (d > mark[i].val)
break;
}
return (i == size) ? ' ' : mark[i].sym;
}
static int
lat_print_timestamp(struct trace_iterator *iter, u64 next_ts)
{
struct trace_array *tr = iter->tr;
unsigned long verbose = tr->trace_flags & TRACE_ITER_VERBOSE;
unsigned long in_ns = iter->iter_flags & TRACE_FILE_TIME_IN_NS;
unsigned long long abs_ts = iter->ts - iter->array_buffer->time_start;
unsigned long long rel_ts = next_ts - iter->ts;
struct trace_seq *s = &iter->seq;
if (in_ns) {
abs_ts = ns2usecs(abs_ts);
rel_ts = ns2usecs(rel_ts);
}
if (verbose && in_ns) {
unsigned long abs_usec = do_div(abs_ts, USEC_PER_MSEC);
unsigned long abs_msec = (unsigned long)abs_ts;
unsigned long rel_usec = do_div(rel_ts, USEC_PER_MSEC);
unsigned long rel_msec = (unsigned long)rel_ts;
trace_seq_printf(
s, "[%08llx] %ld.%03ldms (+%ld.%03ldms): ",
ns2usecs(iter->ts),
abs_msec, abs_usec,
rel_msec, rel_usec);
} else if (verbose && !in_ns) {
trace_seq_printf(
s, "[%016llx] %lld (+%lld): ",
iter->ts, abs_ts, rel_ts);
} else if (!verbose && in_ns) {
trace_seq_printf(
s, " %4lldus%c: ",
abs_ts,
trace_find_mark(rel_ts * NSEC_PER_USEC));
} else { /* !verbose && !in_ns */
trace_seq_printf(s, " %4lld: ", abs_ts);
}
return !trace_seq_has_overflowed(s);
}
static void trace_print_time(struct trace_seq *s, struct trace_iterator *iter,
unsigned long long ts)
{
unsigned long secs, usec_rem;
unsigned long long t;
if (iter->iter_flags & TRACE_FILE_TIME_IN_NS) {
t = ns2usecs(ts);
usec_rem = do_div(t, USEC_PER_SEC);
secs = (unsigned long)t;
trace_seq_printf(s, " %5lu.%06lu", secs, usec_rem);
} else
trace_seq_printf(s, " %12llu", ts);
}
int trace_print_context(struct trace_iterator *iter)
{
struct trace_array *tr = iter->tr;
struct trace_seq *s = &iter->seq;
struct trace_entry *entry = iter->ent;
char comm[TASK_COMM_LEN];
trace_find_cmdline(entry->pid, comm);
trace_seq_printf(s, "%16s-%-7d ", comm, entry->pid);
if (tr->trace_flags & TRACE_ITER_RECORD_TGID) {
unsigned int tgid = trace_find_tgid(entry->pid);
if (!tgid)
trace_seq_printf(s, "(-------) ");
else
trace_seq_printf(s, "(%7d) ", tgid);
}
trace_seq_printf(s, "[%03d] ", iter->cpu);
if (tr->trace_flags & TRACE_ITER_IRQ_INFO)
trace_print_lat_fmt(s, entry);
trace_print_time(s, iter, iter->ts);
trace_seq_puts(s, ": ");
return !trace_seq_has_overflowed(s);
}
int trace_print_lat_context(struct trace_iterator *iter)
{
struct trace_entry *entry, *next_entry;
struct trace_array *tr = iter->tr;
struct trace_seq *s = &iter->seq;
unsigned long verbose = (tr->trace_flags & TRACE_ITER_VERBOSE);
u64 next_ts;
next_entry = trace_find_next_entry(iter, NULL, &next_ts);
if (!next_entry)
next_ts = iter->ts;
/* trace_find_next_entry() may change iter->ent */
entry = iter->ent;
if (verbose) {
char comm[TASK_COMM_LEN];
trace_find_cmdline(entry->pid, comm);
trace_seq_printf(
s, "%16s %7d %3d %d %08x %08lx ",
comm, entry->pid, iter->cpu, entry->flags,
entry->preempt_count & 0xf, iter->idx);
} else {
lat_print_generic(s, entry, iter->cpu);
}
lat_print_timestamp(iter, next_ts);
return !trace_seq_has_overflowed(s);
}
/**
* ftrace_find_event - find a registered event
* @type: the type of event to look for
*
* Returns an event of type @type otherwise NULL
* Called with trace_event_read_lock() held.
*/
struct trace_event *ftrace_find_event(int type)
{
struct trace_event *event;
unsigned key;
key = type & (EVENT_HASHSIZE - 1);
hlist_for_each_entry(event, &event_hash[key], node) {
if (event->type == type)
return event;
}
return NULL;
}
static DEFINE_IDA(trace_event_ida);
static void free_trace_event_type(int type)
{
if (type >= __TRACE_LAST_TYPE)
ida_free(&trace_event_ida, type);
}
static int alloc_trace_event_type(void)
{
int next;
/* Skip static defined type numbers */
next = ida_alloc_range(&trace_event_ida, __TRACE_LAST_TYPE,
TRACE_EVENT_TYPE_MAX, GFP_KERNEL);
if (next < 0)
return 0;
return next;
}
void trace_event_read_lock(void)
{
down_read(&trace_event_sem);
}
void trace_event_read_unlock(void)
{
up_read(&trace_event_sem);
}
/**
* register_trace_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_trace_event(struct trace_event *event)
{
unsigned key;
int ret = 0;
down_write(&trace_event_sem);
if (WARN_ON(!event))
goto out;
if (WARN_ON(!event->funcs))
goto out;
if (!event->type) {
event->type = alloc_trace_event_type();
if (!event->type)
goto out;
} else if (WARN(event->type > __TRACE_LAST_TYPE,
"Need to add type to trace.h")) {
goto out;
} else {
/* Is this event already used */
if (ftrace_find_event(event->type))
goto out;
}
if (event->funcs->trace == NULL)
event->funcs->trace = trace_nop_print;
if (event->funcs->raw == NULL)
event->funcs->raw = trace_nop_print;
if (event->funcs->hex == NULL)
event->funcs->hex = trace_nop_print;
if (event->funcs->binary == NULL)
event->funcs->binary = trace_nop_print;
key = event->type & (EVENT_HASHSIZE - 1);
hlist_add_head(&event->node, &event_hash[key]);
ret = event->type;
out:
up_write(&trace_event_sem);
return ret;
}
EXPORT_SYMBOL_GPL(register_trace_event);
/*
* Used by module code with the trace_event_sem held for write.
*/
int __unregister_trace_event(struct trace_event *event)
{
hlist_del(&event->node);
free_trace_event_type(event->type);
return 0;
}
/**
* unregister_trace_event - remove a no longer used event
* @event: the event to remove
*/
int unregister_trace_event(struct trace_event *event)
{
down_write(&trace_event_sem);
__unregister_trace_event(event);
up_write(&trace_event_sem);
return 0;
}
EXPORT_SYMBOL_GPL(unregister_trace_event);
/*
* Standard events
*/
static void print_array(struct trace_iterator *iter, void *pos,
struct ftrace_event_field *field)
{
int offset;
int len;
int i;
offset = *(int *)pos & 0xffff;
len = *(int *)pos >> 16;
if (field)
offset += field->offset + sizeof(int);
if (offset + len > iter->ent_size) {
trace_seq_puts(&iter->seq, "<OVERFLOW>");
return;
}
pos = (void *)iter->ent + offset;
for (i = 0; i < len; i++, pos++) {
if (i)
trace_seq_putc(&iter->seq, ',');
trace_seq_printf(&iter->seq, "%02x", *(unsigned char *)pos);
}
}
static void print_fields(struct trace_iterator *iter, struct trace_event_call *call,
struct list_head *head)
{
struct ftrace_event_field *field;
int offset;
int len;
int ret;
void *pos;
list_for_each_entry_reverse(field, head, link) {
trace_seq_printf(&iter->seq, " %s=", field->name);
if (field->offset + field->size > iter->ent_size) {
trace_seq_puts(&iter->seq, "<OVERFLOW>");
continue;
}
pos = (void *)iter->ent + field->offset;
switch (field->filter_type) {
case FILTER_COMM:
case FILTER_STATIC_STRING:
trace_seq_printf(&iter->seq, "%.*s", field->size, (char *)pos);
break;
case FILTER_RDYN_STRING:
case FILTER_DYN_STRING:
offset = *(int *)pos & 0xffff;
len = *(int *)pos >> 16;
if (field->filter_type == FILTER_RDYN_STRING)
offset += field->offset + sizeof(int);
if (offset + len > iter->ent_size) {
trace_seq_puts(&iter->seq, "<OVERFLOW>");
break;
}
pos = (void *)iter->ent + offset;
trace_seq_printf(&iter->seq, "%.*s", len, (char *)pos);
break;
case FILTER_PTR_STRING:
if (!iter->fmt_size)
trace_iter_expand_format(iter);
pos = *(void **)pos;
ret = strncpy_from_kernel_nofault(iter->fmt, pos,
iter->fmt_size);
if (ret < 0)
trace_seq_printf(&iter->seq, "(0x%px)", pos);
else
trace_seq_printf(&iter->seq, "(0x%px:%s)",
pos, iter->fmt);
break;
case FILTER_TRACE_FN:
pos = *(void **)pos;
trace_seq_printf(&iter->seq, "%pS", pos);
break;
case FILTER_CPU:
case FILTER_OTHER:
switch (field->size) {
case 1:
if (isprint(*(char *)pos)) {
trace_seq_printf(&iter->seq, "'%c'",
*(unsigned char *)pos);
}
trace_seq_printf(&iter->seq, "(%d)",
*(unsigned char *)pos);
break;
case 2:
trace_seq_printf(&iter->seq, "0x%x (%d)",
*(unsigned short *)pos,
*(unsigned short *)pos);
break;
case 4:
/* dynamic array info is 4 bytes */
if (strstr(field->type, "__data_loc")) {
print_array(iter, pos, NULL);
break;
}
if (strstr(field->type, "__rel_loc")) {
print_array(iter, pos, field);
break;
}
trace_seq_printf(&iter->seq, "0x%x (%d)",
*(unsigned int *)pos,
*(unsigned int *)pos);
break;
case 8:
trace_seq_printf(&iter->seq, "0x%llx (%lld)",
*(unsigned long long *)pos,
*(unsigned long long *)pos);
break;
default:
trace_seq_puts(&iter->seq, "<INVALID-SIZE>");
break;
}
break;
default:
trace_seq_puts(&iter->seq, "<INVALID-TYPE>");
}
}
trace_seq_putc(&iter->seq, '\n');
}
enum print_line_t print_event_fields(struct trace_iterator *iter,
struct trace_event *event)
{
struct trace_event_call *call;
struct list_head *head;
/* ftrace defined events have separate call structures */
if (event->type <= __TRACE_LAST_TYPE) {
bool found = false;
down_read(&trace_event_sem);
list_for_each_entry(call, &ftrace_events, list) {
if (call->event.type == event->type) {
found = true;
break;
}
/* No need to search all events */
if (call->event.type > __TRACE_LAST_TYPE)
break;
}
up_read(&trace_event_sem);
if (!found) {
trace_seq_printf(&iter->seq, "UNKNOWN TYPE %d\n", event->type);
goto out;
}
} else {
call = container_of(event, struct trace_event_call, event);
}
head = trace_get_fields(call);
trace_seq_printf(&iter->seq, "%s:", trace_event_name(call));
if (head && !list_empty(head))
print_fields(iter, call, head);
else
trace_seq_puts(&iter->seq, "No fields found\n");
out:
return trace_handle_return(&iter->seq);
}
enum print_line_t trace_nop_print(struct trace_iterator *iter, int flags,
struct trace_event *event)
{
trace_seq_printf(&iter->seq, "type: %d\n", iter->ent->type);
return trace_handle_return(&iter->seq);
}
static void print_fn_trace(struct trace_seq *s, unsigned long ip,
unsigned long parent_ip, int flags)
{
seq_print_ip_sym(s, ip, flags);