linux/kernel/trace/trace_output.c
Linus Torvalds cccf0c2ee5 Tracing updates for 6.5:
- Add new feature to have function graph tracer record the return value.
   Adds a new option: funcgraph-retval ; when set, will show the return
   value of a function in the function graph tracer.
 
 - Also add the option: funcgraph-retval-hex where if it is not set, and
   the return value is an error code, then it will return the decimal of
   the error code, otherwise it still reports the hex value.
 
 - Add the file /sys/kernel/tracing/osnoise/per_cpu/cpu<cpu>/timerlat_fd
   That when a application opens it, it becomes the task that the timer lat
   tracer traces. The application can also read this file to find out how
   it's being interrupted.
 
 - Add the file /sys/kernel/tracing/available_filter_functions_addrs
   that works just the same as available_filter_functions but also shows
   the addresses of the functions like kallsyms, except that it gives the
   address of where the fentry/mcount jump/nop is. This is used by BPF to
   make it easier to attach BPF programs to ftrace hooks.
 
 - Replace strlcpy with strscpy in the tracing boot code.
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Merge tag 'trace-v6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull tracing updates from Steven Rostedt:

 - Add new feature to have function graph tracer record the return
   value. Adds a new option: funcgraph-retval ; when set, will show the
   return value of a function in the function graph tracer.

 - Also add the option: funcgraph-retval-hex where if it is not set, and
   the return value is an error code, then it will return the decimal of
   the error code, otherwise it still reports the hex value.

 - Add the file /sys/kernel/tracing/osnoise/per_cpu/cpu<cpu>/timerlat_fd
   That when a application opens it, it becomes the task that the timer
   lat tracer traces. The application can also read this file to find
   out how it's being interrupted.

 - Add the file /sys/kernel/tracing/available_filter_functions_addrs
   that works just the same as available_filter_functions but also shows
   the addresses of the functions like kallsyms, except that it gives
   the address of where the fentry/mcount jump/nop is. This is used by
   BPF to make it easier to attach BPF programs to ftrace hooks.

 - Replace strlcpy with strscpy in the tracing boot code.

* tag 'trace-v6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  tracing: Fix warnings when building htmldocs for function graph retval
  riscv: ftrace: Enable HAVE_FUNCTION_GRAPH_RETVAL
  tracing/boot: Replace strlcpy with strscpy
  tracing/timerlat: Add user-space interface
  tracing/osnoise: Skip running osnoise if all instances are off
  tracing/osnoise: Switch from PF_NO_SETAFFINITY to migrate_disable
  ftrace: Show all functions with addresses in available_filter_functions_addrs
  selftests/ftrace: Add funcgraph-retval test case
  LoongArch: ftrace: Enable HAVE_FUNCTION_GRAPH_RETVAL
  x86/ftrace: Enable HAVE_FUNCTION_GRAPH_RETVAL
  arm64: ftrace: Enable HAVE_FUNCTION_GRAPH_RETVAL
  tracing: Add documentation for funcgraph-retval and funcgraph-retval-hex
  function_graph: Support recording and printing the return value of function
  fgraph: Add declaration of "struct fgraph_ret_regs"
2023-06-30 10:33:17 -07:00

1726 lines
39 KiB
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 <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, ...)
{
va_list ap;
va_start(ap, fmt);
trace_check_vprintf(iter, 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);
if ((flags & TRACE_ITER_PRINT_PARENT) && parent_ip) {
trace_seq_puts(s, " <-");
seq_print_ip_sym(s, parent_ip, flags);
}
}
/* TRACE_FN */
static enum print_line_t trace_fn_trace(struct trace_iterator *iter, int flags,
struct trace_event *event)
{
struct ftrace_entry *field;
struct trace_seq *s = &iter->seq;
trace_assign_type(field, iter->ent);
print_fn_trace(s, field->ip, field->parent_ip, flags);
trace_seq_putc(s, '\n');
return trace_handle_return(s);
}
static enum print_line_t trace_fn_raw(struct trace_iterator *iter, int flags,
struct trace_event *event)
{
struct ftrace_entry *field;
trace_assign_type(field, iter->ent);
trace_seq_printf(&iter->seq, "%lx %lx\n",
field->ip,
field->parent_ip);
return trace_handle_return(&iter->seq);
}
static enum print_line_t trace_fn_hex(struct trace_iterator *iter, int flags,
struct trace_event *event)
{
struct ftrace_entry *field;
struct trace_seq *s = &iter->seq;
trace_assign_type(field, iter->ent);
SEQ_PUT_HEX_FIELD(s, field->ip);
SEQ_PUT_HEX_FIELD(s, field->parent_ip);
return trace_handle_return(s);
}
static enum print_line_t trace_fn_bin(struct trace_iterator *iter, int flags,
struct trace_event *event)
{
struct ftrace_entry *field;
struct trace_seq *s = &iter->seq;
trace_assign_type(field, iter->ent);
SEQ_PUT_FIELD(s, field->ip);
SEQ_PUT_FIELD(s, field->parent_ip);
return trace_handle_return(s);
}
static struct trace_event_functions trace_fn_funcs = {
.trace = trace_fn_trace,
.raw = trace_fn_raw,
.hex = trace_fn_hex,
.binary = trace_fn_bin,
};
static struct trace_event trace_fn_event = {
.type = TRACE_FN,
.funcs = &trace_fn_funcs,
};
/* TRACE_CTX an TRACE_WAKE */
static enum print_line_t trace_ctxwake_print(struct trace_iterator *iter,
char *delim)
{
struct ctx_switch_entry *field;
char comm[TASK_COMM_LEN];
int S, T;
trace_assign_type(field, iter->ent);
T = task_index_to_char(field->next_state);
S = task_index_to_char(field->prev_state);
trace_find_cmdline(field->next_pid, comm);
trace_seq_printf(&iter->seq,
" %7d:%3d:%c %s [%03d] %7d:%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_handle_return(&iter->seq);
}
static enum print_line_t trace_ctx_print(struct trace_iterator *iter, int flags,
struct trace_event *event)
{
return trace_ctxwake_print(iter, "==>");
}
static enum print_line_t trace_wake_print(struct trace_iterator *iter,
int flags, struct trace_event *event)
{
return trace_ctxwake_print(iter, " +");
}
static int trace_ctxwake_raw(struct trace_iterator *iter, char S)
{
struct ctx_switch_entry *field;
int T;
trace_assign_type(field, iter->ent);
if (!S)
S = task_index_to_char(field->prev_state);
T = task_index_to_char(field->next_state);
trace_seq_printf(&iter->seq, "%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_handle_return(&iter->seq);
}
static enum print_line_t trace_ctx_raw(struct trace_iterator *iter, int flags,
struct trace_event *event)
{
return trace_ctxwake_raw(iter, 0);
}
static enum print_line_t trace_wake_raw(struct trace_iterator *iter, int flags,
struct trace_event *event)
{
return trace_ctxwake_raw(iter, '+');
}
static int trace_ctxwake_hex(struct trace_iterator *iter, char S)
{
struct ctx_switch_entry *field;
struct trace_seq *s = &iter->seq;
int T;
trace_assign_type(field, iter->ent);
if (!S)
S = task_index_to_char(field->prev_state);
T = task_index_to_char(field->next_state);
SEQ_PUT_HEX_FIELD(s, field->prev_pid);
SEQ_PUT_HEX_FIELD(s, field->prev_prio);
SEQ_PUT_HEX_FIELD(s, S);
SEQ_PUT_HEX_FIELD(s, field->next_cpu);
SEQ_PUT_HEX_FIELD(s, field->next_pid);
SEQ_PUT_HEX_FIELD(s, field->next_prio);
SEQ_PUT_HEX_FIELD(s, T);
return trace_handle_return(s);
}
static enum print_line_t trace_ctx_hex(struct trace_iterator *iter, int flags,
struct trace_event *event)
{
return trace_ctxwake_hex(iter, 0);
}
static enum print_line_t trace_wake_hex(struct trace_iterator *iter, int flags,
struct trace_event *event)
{
return trace_ctxwake_hex(iter, '+');
}
static enum print_line_t trace_ctxwake_bin(struct trace_iterator *iter,
int flags, struct trace_event *event)
{
struct ctx_switch_entry *field;
struct trace_seq *s = &iter->seq;
trace_assign_type(field, iter->ent);
SEQ_PUT_FIELD(s, field->prev_pid);
SEQ_PUT_FIELD(s, field->prev_prio);
SEQ_PUT_FIELD(s, field->prev_state);
SEQ_PUT_FIELD(s, field->next_cpu);
SEQ_PUT_FIELD(s, field->next_pid);
SEQ_PUT_FIELD(s, field->next_prio);
SEQ_PUT_FIELD(s, field->next_state);
return trace_handle_return(s);
}
static struct trace_event_functions trace_ctx_funcs = {
.trace = trace_ctx_print,
.raw = trace_ctx_raw,
.hex = trace_ctx_hex,
.binary = trace_ctxwake_bin,
};
static struct trace_event trace_ctx_event = {
.type = TRACE_CTX,
.funcs = &trace_ctx_funcs,
};
static struct trace_event_functions trace_wake_funcs = {
.trace = trace_wake_print,
.raw = trace_wake_raw,
.hex = trace_wake_hex,
.binary = trace_ctxwake_bin,
};
static struct trace_event trace_wake_event = {
.type = TRACE_WAKE,
.funcs = &trace_wake_funcs,
};
/* TRACE_STACK */
static enum print_line_t trace_stack_print(struct trace_iterator *iter,
int flags, struct trace_event *event)
{
struct stack_entry *field;
struct trace_seq *s = &iter->seq;
unsigned long *p;
unsigned long *end;
trace_assign_type(field, iter->ent);
end = (unsigned long *)((long)iter->ent + iter->ent_size);
trace_seq_puts(s, "<stack trace>\n");
for (p = field->caller; p && p < end && *p != ULONG_MAX; p++) {
if (trace_seq_has_overflowed(s))
break;
trace_seq_puts(s, " => ");
seq_print_ip_sym(s, *p, flags);
trace_seq_putc(s, '\n');
}
return trace_handle_return(s);
}
static struct trace_event_functions trace_stack_funcs = {
.trace = trace_stack_print,
};
static struct trace_event trace_stack_event = {
.type = TRACE_STACK,
.funcs = &trace_stack_funcs,
};
/* TRACE_USER_STACK */
static enum print_line_t trace_user_stack_print(struct trace_iterator *iter,
int flags, struct trace_event *event)
{
struct trace_array *tr = iter->tr;
struct userstack_entry *field;
struct trace_seq *s = &iter->seq;
struct mm_struct *mm = NULL;
unsigned int i;
trace_assign_type(field, iter->ent);
trace_seq_puts(s, "<user stack trace>\n");
if (tr->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(field->tgid);
if (task)
mm = get_task_mm(task);
rcu_read_unlock();
}
for (i = 0; i < FTRACE_STACK_ENTRIES; i++) {
unsigned long ip = field->caller[i];
if (!ip || trace_seq_has_overflowed(s))
break;
trace_seq_puts(s, " => ");
seq_print_user_ip(s, mm, ip, flags);
trace_seq_putc(s, '\n');
}
if (mm)
mmput(mm);
return trace_handle_return(s);
}
static struct trace_event_functions trace_user_stack_funcs = {
.trace = trace_user_stack_print,
};
static struct trace_event trace_user_stack_event = {
.type = TRACE_USER_STACK,
.funcs = &trace_user_stack_funcs,
};
/* TRACE_HWLAT */
static enum print_line_t
trace_hwlat_print(struct trace_iterator *iter, int flags,
struct trace_event *event)
{
struct trace_entry *entry = iter->ent;
struct trace_seq *s = &iter->seq;
struct hwlat_entry *field;
trace_assign_type(field, entry);
trace_seq_printf(s, "#%-5u inner/outer(us): %4llu/%-5llu ts:%lld.%09ld count:%d",
field->seqnum,
field->duration,
field->outer_duration,
(long long)field->timestamp.tv_sec,
field->timestamp.tv_nsec, field->count);
if (field->nmi_count) {
/*
* The generic sched_clock() is not NMI safe, thus
* we only record the count and not the time.
*/
if (!IS_ENABLED(CONFIG_GENERIC_SCHED_CLOCK))
trace_seq_printf(s, " nmi-total:%llu",
field->nmi_total_ts);
trace_seq_printf(s, " nmi-count:%u",
field->nmi_count);
}
trace_seq_putc(s, '\n');
return trace_handle_return(s);
}
static enum print_line_t
trace_hwlat_raw(struct trace_iterator *iter, int flags,
struct trace_event *event)
{
struct hwlat_entry *field;
struct trace_seq *s = &iter->seq;
trace_assign_type(field, iter->ent);
trace_seq_printf(s, "%llu %lld %lld %09ld %u\n",
field->duration,
field->outer_duration,
(long long)field->timestamp.tv_sec,
field->timestamp.tv_nsec,
field->seqnum);
return trace_handle_return(s);
}
static struct trace_event_functions trace_hwlat_funcs = {
.trace = trace_hwlat_print,
.raw = trace_hwlat_raw,
};
static struct trace_event trace_hwlat_event = {
.type = TRACE_HWLAT,
.funcs = &trace_hwlat_funcs,
};
/* TRACE_OSNOISE */
static enum print_line_t
trace_osnoise_print(struct trace_iterator *iter, int flags,
struct trace_event *event)
{
struct trace_entry *entry = iter->ent;
struct trace_seq *s = &iter->seq;
struct osnoise_entry *field;
u64 ratio, ratio_dec;
u64 net_runtime;
trace_assign_type(field, entry);
/*
* compute the available % of cpu time.
*/
net_runtime = field->runtime - field->noise;
ratio = net_runtime * 10000000;
do_div(ratio, field->runtime);
ratio_dec = do_div(ratio, 100000);
trace_seq_printf(s, "%llu %10llu %3llu.%05llu %7llu",
field->runtime,
field->noise,
ratio, ratio_dec,
field->max_sample);
trace_seq_printf(s, " %6u", field->hw_count);
trace_seq_printf(s, " %6u", field->nmi_count);
trace_seq_printf(s, " %6u", field->irq_count);
trace_seq_printf(s, " %6u", field->softirq_count);
trace_seq_printf(s, " %6u", field->thread_count);
trace_seq_putc(s, '\n');
return trace_handle_return(s);
}
static enum print_line_t
trace_osnoise_raw(struct trace_iterator *iter, int flags,
struct trace_event *event)
{
struct osnoise_entry *field;
struct trace_seq *s = &iter->seq;
trace_assign_type(field, iter->ent);
trace_seq_printf(s, "%lld %llu %llu %u %u %u %u %u\n",
field->runtime,
field->noise,
field->max_sample,
field->hw_count,
field->nmi_count,
field->irq_count,
field->softirq_count,
field->thread_count);
return trace_handle_return(s);
}
static struct trace_event_functions trace_osnoise_funcs = {
.trace = trace_osnoise_print,
.raw = trace_osnoise_raw,
};
static struct trace_event trace_osnoise_event = {
.type = TRACE_OSNOISE,
.funcs = &trace_osnoise_funcs,
};
/* TRACE_TIMERLAT */
static char *timerlat_lat_context[] = {"irq", "thread", "user-ret"};
static enum print_line_t
trace_timerlat_print(struct trace_iterator *iter, int flags,
struct trace_event *event)
{
struct trace_entry *entry = iter->ent;
struct trace_seq *s = &iter->seq;
struct timerlat_entry *field;
trace_assign_type(field, entry);
trace_seq_printf(s, "#%-5u context %6s timer_latency %9llu ns\n",
field->seqnum,
timerlat_lat_context[field->context],
field->timer_latency);
return trace_handle_return(s);
}
static enum print_line_t
trace_timerlat_raw(struct trace_iterator *iter, int flags,
struct trace_event *event)
{
struct timerlat_entry *field;
struct trace_seq *s = &iter->seq;
trace_assign_type(field, iter->ent);
trace_seq_printf(s, "%u %d %llu\n",
field->seqnum,
field->context,
field->timer_latency);
return trace_handle_return(s);
}
static struct trace_event_functions trace_timerlat_funcs = {
.trace = trace_timerlat_print,
.raw = trace_timerlat_raw,
};
static struct trace_event trace_timerlat_event = {
.type = TRACE_TIMERLAT,
.funcs = &trace_timerlat_funcs,
};
/* TRACE_BPUTS */
static enum print_line_t
trace_bputs_print(struct trace_iterator *iter, int flags,
struct trace_event *event)
{
struct trace_entry *entry = iter->ent;
struct trace_seq *s = &iter->seq;
struct bputs_entry *field;
trace_assign_type(field, entry);
seq_print_ip_sym(s, field->ip, flags);
trace_seq_puts(s, ": ");
trace_seq_puts(s, field->str);
return trace_handle_return(s);
}
static enum print_line_t
trace_bputs_raw(struct trace_iterator *iter, int flags,
struct trace_event *event)
{
struct bputs_entry *field;
struct trace_seq *s = &iter->seq;
trace_assign_type(field, iter->ent);
trace_seq_printf(s, ": %lx : ", field->ip);
trace_seq_puts(s, field->str);
return trace_handle_return(s);
}
static struct trace_event_functions trace_bputs_funcs = {
.trace = trace_bputs_print,
.raw = trace_bputs_raw,
};
static struct trace_event trace_bputs_event = {
.type = TRACE_BPUTS,
.funcs = &trace_bputs_funcs,
};
/* TRACE_BPRINT */
static enum print_line_t
trace_bprint_print(struct trace_iterator *iter, int flags,
struct trace_event *event)
{
struct trace_entry *entry = iter->ent;
struct trace_seq *s = &iter->seq;
struct bprint_entry *field;
trace_assign_type(field, entry);
seq_print_ip_sym(s, field->ip, flags);
trace_seq_puts(s, ": ");
trace_seq_bprintf(s, field->fmt, field->buf);
return trace_handle_return(s);
}
static enum print_line_t
trace_bprint_raw(struct trace_iterator *iter, int flags,
struct trace_event *event)
{
struct bprint_entry *field;
struct trace_seq *s = &iter->seq;
trace_assign_type(field, iter->ent);
trace_seq_printf(s, ": %lx : ", field->ip);
trace_seq_bprintf(s, field->fmt, field->buf);
return trace_handle_return(s);
}
static struct trace_event_functions trace_bprint_funcs = {
.trace = trace_bprint_print,
.raw = trace_bprint_raw,
};
static struct trace_event trace_bprint_event = {
.type = TRACE_BPRINT,
.funcs = &trace_bprint_funcs,
};
/* TRACE_PRINT */
static enum print_line_t trace_print_print(struct trace_iterator *iter,
int flags, struct trace_event *event)
{
struct print_entry *field;
struct trace_seq *s = &iter->seq;
trace_assign_type(field, iter->ent);
seq_print_ip_sym(s, field->ip, flags);
trace_seq_printf(s, ": %s", field->buf);
return trace_handle_return(s);
}
static enum print_line_t trace_print_raw(struct trace_iterator *iter, int flags,
struct trace_event *event)
{
struct print_entry *field;
trace_assign_type(field, iter->ent);
trace_seq_printf(&iter->seq, "# %lx %s", field->ip, field->buf);
return trace_handle_return(&iter->seq);
}
static struct trace_event_functions trace_print_funcs = {
.trace = trace_print_print,
.raw = trace_print_raw,
};
static struct trace_event trace_print_event = {
.type = TRACE_PRINT,
.funcs = &trace_print_funcs,
};
static enum print_line_t trace_raw_data(struct trace_iterator *iter, int flags,
struct trace_event *event)
{
struct raw_data_entry *field;
int i;
trace_assign_type(field, iter->ent);
trace_seq_printf(&iter->seq, "# %x buf:", field->id);
for (i = 0; i < iter->ent_size - offsetof(struct raw_data_entry, buf); i++)
trace_seq_printf(&iter->seq, " %02x",
(unsigned char)field->buf[i]);
trace_seq_putc(&iter->seq, '\n');
return trace_handle_return(&iter->seq);
}
static struct trace_event_functions trace_raw_data_funcs = {
.trace = trace_raw_data,
.raw = trace_raw_data,
};
static struct trace_event trace_raw_data_event = {
.type = TRACE_RAW_DATA,
.funcs = &trace_raw_data_funcs,
};
static enum print_line_t
trace_func_repeats_raw(struct trace_iterator *iter, int flags,
struct trace_event *event)
{
struct func_repeats_entry *field;
struct trace_seq *s = &iter->seq;
trace_assign_type(field, iter->ent);
trace_seq_printf(s, "%lu %lu %u %llu\n",
field->ip,
field->parent_ip,
field->count,
FUNC_REPEATS_GET_DELTA_TS(field));
return trace_handle_return(s);
}
static enum print_line_t
trace_func_repeats_print(struct trace_iterator *iter, int flags,
struct trace_event *event)
{
struct func_repeats_entry *field;
struct trace_seq *s = &iter->seq;
trace_assign_type(field, iter->ent);
print_fn_trace(s, field->ip, field->parent_ip, flags);
trace_seq_printf(s, " (repeats: %u, last_ts:", field->count);
trace_print_time(s, iter,
iter->ts - FUNC_REPEATS_GET_DELTA_TS(field));
trace_seq_puts(s, ")\n");
return trace_handle_return(s);
}
static struct trace_event_functions trace_func_repeats_funcs = {
.trace = trace_func_repeats_print,
.raw = trace_func_repeats_raw,
};
static struct trace_event trace_func_repeats_event = {
.type = TRACE_FUNC_REPEATS,
.funcs = &trace_func_repeats_funcs,
};
static struct trace_event *events[] __initdata = {
&trace_fn_event,
&trace_ctx_event,
&trace_wake_event,
&trace_stack_event,
&trace_user_stack_event,
&trace_bputs_event,
&trace_bprint_event,
&trace_print_event,
&trace_hwlat_event,
&trace_osnoise_event,
&trace_timerlat_event,
&trace_raw_data_event,
&trace_func_repeats_event,
NULL
};
__init int init_events(void)
{
struct trace_event *event;
int i, ret;
for (i = 0; events[i]; i++) {
event = events[i];
ret = register_trace_event(event);
WARN_ONCE(!ret, "event %d failed to register", event->type);
}
return 0;
}