https://github.com/torvalds/linux
Tip revision: 50c4c4e268a2d7a3e58ebb698ac74da0de40ae36 authored by Linus Torvalds on 11 December 2017, 01:56:26 UTC
Linux 4.15-rc3
Linux 4.15-rc3
Tip revision: 50c4c4e
debug.c
// SPDX-License-Identifier: GPL-2.0
/* For general debugging purposes */
#include "../perf.h"
#include <inttypes.h>
#include <string.h>
#include <stdarg.h>
#include <stdio.h>
#include <sys/wait.h>
#include <api/debug.h>
#include <linux/time64.h>
#ifdef HAVE_BACKTRACE_SUPPORT
#include <execinfo.h>
#endif
#include "cache.h"
#include "color.h"
#include "event.h"
#include "debug.h"
#include "print_binary.h"
#include "util.h"
#include "target.h"
#include "sane_ctype.h"
int verbose;
bool dump_trace = false, quiet = false;
int debug_ordered_events;
static int redirect_to_stderr;
int debug_data_convert;
int veprintf(int level, int var, const char *fmt, va_list args)
{
int ret = 0;
if (var >= level) {
if (use_browser >= 1 && !redirect_to_stderr)
ui_helpline__vshow(fmt, args);
else
ret = vfprintf(stderr, fmt, args);
}
return ret;
}
int eprintf(int level, int var, const char *fmt, ...)
{
va_list args;
int ret;
va_start(args, fmt);
ret = veprintf(level, var, fmt, args);
va_end(args);
return ret;
}
static int veprintf_time(u64 t, const char *fmt, va_list args)
{
int ret = 0;
u64 secs, usecs, nsecs = t;
secs = nsecs / NSEC_PER_SEC;
nsecs -= secs * NSEC_PER_SEC;
usecs = nsecs / NSEC_PER_USEC;
ret = fprintf(stderr, "[%13" PRIu64 ".%06" PRIu64 "] ",
secs, usecs);
ret += vfprintf(stderr, fmt, args);
return ret;
}
int eprintf_time(int level, int var, u64 t, const char *fmt, ...)
{
int ret = 0;
va_list args;
if (var >= level) {
va_start(args, fmt);
ret = veprintf_time(t, fmt, args);
va_end(args);
}
return ret;
}
/*
* Overloading libtraceevent standard info print
* function, display with -v in perf.
*/
void pr_stat(const char *fmt, ...)
{
va_list args;
va_start(args, fmt);
veprintf(1, verbose, fmt, args);
va_end(args);
eprintf(1, verbose, "\n");
}
int dump_printf(const char *fmt, ...)
{
va_list args;
int ret = 0;
if (dump_trace) {
va_start(args, fmt);
ret = vprintf(fmt, args);
va_end(args);
}
return ret;
}
static int trace_event_printer(enum binary_printer_ops op,
unsigned int val, void *extra, FILE *fp)
{
const char *color = PERF_COLOR_BLUE;
union perf_event *event = (union perf_event *)extra;
unsigned char ch = (unsigned char)val;
int printed = 0;
switch (op) {
case BINARY_PRINT_DATA_BEGIN:
printed += fprintf(fp, ".");
printed += color_fprintf(fp, color, "\n. ... raw event: size %d bytes\n",
event->header.size);
break;
case BINARY_PRINT_LINE_BEGIN:
printed += fprintf(fp, ".");
break;
case BINARY_PRINT_ADDR:
printed += color_fprintf(fp, color, " %04x: ", val);
break;
case BINARY_PRINT_NUM_DATA:
printed += color_fprintf(fp, color, " %02x", val);
break;
case BINARY_PRINT_NUM_PAD:
printed += color_fprintf(fp, color, " ");
break;
case BINARY_PRINT_SEP:
printed += color_fprintf(fp, color, " ");
break;
case BINARY_PRINT_CHAR_DATA:
printed += color_fprintf(fp, color, "%c",
isprint(ch) ? ch : '.');
break;
case BINARY_PRINT_CHAR_PAD:
printed += color_fprintf(fp, color, " ");
break;
case BINARY_PRINT_LINE_END:
printed += color_fprintf(fp, color, "\n");
break;
case BINARY_PRINT_DATA_END:
printed += fprintf(fp, "\n");
break;
default:
break;
}
return printed;
}
void trace_event(union perf_event *event)
{
unsigned char *raw_event = (void *)event;
if (!dump_trace)
return;
print_binary(raw_event, event->header.size, 16,
trace_event_printer, event);
}
static struct debug_variable {
const char *name;
int *ptr;
} debug_variables[] = {
{ .name = "verbose", .ptr = &verbose },
{ .name = "ordered-events", .ptr = &debug_ordered_events},
{ .name = "stderr", .ptr = &redirect_to_stderr},
{ .name = "data-convert", .ptr = &debug_data_convert },
{ .name = NULL, }
};
int perf_debug_option(const char *str)
{
struct debug_variable *var = &debug_variables[0];
char *vstr, *s = strdup(str);
int v = 1;
vstr = strchr(s, '=');
if (vstr)
*vstr++ = 0;
while (var->name) {
if (!strcmp(s, var->name))
break;
var++;
}
if (!var->name) {
pr_err("Unknown debug variable name '%s'\n", s);
free(s);
return -1;
}
if (vstr) {
v = atoi(vstr);
/*
* Allow only values in range (0, 10),
* otherwise set 0.
*/
v = (v < 0) || (v > 10) ? 0 : v;
}
if (quiet)
v = -1;
*var->ptr = v;
free(s);
return 0;
}
int perf_quiet_option(void)
{
struct debug_variable *var = &debug_variables[0];
/* disable all debug messages */
while (var->name) {
*var->ptr = -1;
var++;
}
quiet = true;
return 0;
}
#define DEBUG_WRAPPER(__n, __l) \
static int pr_ ## __n ## _wrapper(const char *fmt, ...) \
{ \
va_list args; \
int ret; \
\
va_start(args, fmt); \
ret = veprintf(__l, verbose, fmt, args); \
va_end(args); \
return ret; \
}
DEBUG_WRAPPER(warning, 0);
DEBUG_WRAPPER(debug, 1);
void perf_debug_setup(void)
{
libapi_set_print(pr_warning_wrapper, pr_warning_wrapper, pr_debug_wrapper);
}
/* Obtain a backtrace and print it to stdout. */
#ifdef HAVE_BACKTRACE_SUPPORT
void dump_stack(void)
{
void *array[16];
size_t size = backtrace(array, ARRAY_SIZE(array));
char **strings = backtrace_symbols(array, size);
size_t i;
printf("Obtained %zd stack frames.\n", size);
for (i = 0; i < size; i++)
printf("%s\n", strings[i]);
free(strings);
}
#else
void dump_stack(void) {}
#endif
void sighandler_dump_stack(int sig)
{
psignal(sig, "perf");
dump_stack();
signal(sig, SIG_DFL);
raise(sig);
}