/*
* lib/dynamic_debug.c
*
* make pr_debug()/dev_dbg() calls runtime configurable based upon their
* source module.
*
* Copyright (C) 2008 Jason Baron <jbaron@redhat.com>
* By Greg Banks <gnb@melbourne.sgi.com>
* Copyright (c) 2008 Silicon Graphics Inc. All Rights Reserved.
* Copyright (C) 2011 Bart Van Assche. All Rights Reserved.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ":%s: " fmt, __func__
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/kallsyms.h>
#include <linux/types.h>
#include <linux/mutex.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/list.h>
#include <linux/sysctl.h>
#include <linux/ctype.h>
#include <linux/string.h>
#include <linux/uaccess.h>
#include <linux/dynamic_debug.h>
#include <linux/debugfs.h>
#include <linux/slab.h>
#include <linux/jump_label.h>
#include <linux/hardirq.h>
#include <linux/sched.h>
#include <linux/device.h>
#include <linux/netdevice.h>
extern struct _ddebug __start___verbose[];
extern struct _ddebug __stop___verbose[];
struct ddebug_table {
struct list_head link;
char *mod_name;
unsigned int num_ddebugs;
struct _ddebug *ddebugs;
};
struct ddebug_query {
const char *filename;
const char *module;
const char *function;
const char *format;
unsigned int first_lineno, last_lineno;
};
struct ddebug_iter {
struct ddebug_table *table;
unsigned int idx;
};
static DEFINE_MUTEX(ddebug_lock);
static LIST_HEAD(ddebug_tables);
static int verbose;
module_param(verbose, int, 0644);
/* Return the path relative to source root */
static inline const char *trim_prefix(const char *path)
{
int skip = strlen(__FILE__) - strlen("lib/dynamic_debug.c");
if (strncmp(path, __FILE__, skip))
skip = 0; /* prefix mismatch, don't skip */
return path + skip;
}
static struct { unsigned flag:8; char opt_char; } opt_array[] = {
{ _DPRINTK_FLAGS_PRINT, 'p' },
{ _DPRINTK_FLAGS_INCL_MODNAME, 'm' },
{ _DPRINTK_FLAGS_INCL_FUNCNAME, 'f' },
{ _DPRINTK_FLAGS_INCL_LINENO, 'l' },
{ _DPRINTK_FLAGS_INCL_TID, 't' },
{ _DPRINTK_FLAGS_NONE, '_' },
};
/* format a string into buf[] which describes the _ddebug's flags */
static char *ddebug_describe_flags(struct _ddebug *dp, char *buf,
size_t maxlen)
{
char *p = buf;
int i;
BUG_ON(maxlen < 6);
for (i = 0; i < ARRAY_SIZE(opt_array); ++i)
if (dp->flags & opt_array[i].flag)
*p++ = opt_array[i].opt_char;
if (p == buf)
*p++ = '_';
*p = '\0';
return buf;
}
#define vpr_info(fmt, ...) \
do { \
if (verbose) \
pr_info(fmt, ##__VA_ARGS__); \
} while (0)
static void vpr_info_dq(const struct ddebug_query *query, const char *msg)
{
/* trim any trailing newlines */
int fmtlen = 0;
if (query->format) {
fmtlen = strlen(query->format);
while (fmtlen && query->format[fmtlen - 1] == '\n')
fmtlen--;
}
vpr_info("%s: func=\"%s\" file=\"%s\" module=\"%s\" format=\"%.*s\" lineno=%u-%u\n",
msg,
query->function ? query->function : "",
query->filename ? query->filename : "",
query->module ? query->module : "",
fmtlen, query->format ? query->format : "",
query