dynamic_debug.h
#ifndef _DYNAMIC_DEBUG_H
#define _DYNAMIC_DEBUG_H
#if defined(CC_HAVE_ASM_GOTO) && defined(CONFIG_JUMP_LABEL)
#include <linux/jump_label.h>
#endif
/*
* An instance of this structure is created in a special
* ELF section at every dynamic debug callsite. At runtime,
* the special section is treated as an array of these.
*/
struct _ddebug {
/*
* These fields are used to drive the user interface
* for selecting and displaying debug callsites.
*/
const char *modname;
const char *function;
const char *filename;
const char *format;
unsigned int lineno:18;
/*
* The flags field controls the behaviour at the callsite.
* The bits here are changed dynamically when the user
* writes commands to <debugfs>/dynamic_debug/control
*/
#define _DPRINTK_FLAGS_NONE 0
#define _DPRINTK_FLAGS_PRINT (1<<0) /* printk() a message using the format */
#define _DPRINTK_FLAGS_INCL_MODNAME (1<<1)
#define _DPRINTK_FLAGS_INCL_FUNCNAME (1<<2)
#define _DPRINTK_FLAGS_INCL_LINENO (1<<3)
#define _DPRINTK_FLAGS_INCL_TID (1<<4)
#if defined DEBUG
#define _DPRINTK_FLAGS_DEFAULT _DPRINTK_FLAGS_PRINT
#else
#define _DPRINTK_FLAGS_DEFAULT 0
#endif
unsigned int flags:8;
#ifdef HAVE_JUMP_LABEL
union {
struct static_key_true dd_key_true;
struct static_key_false dd_key_false;
} key;
#endif
} __attribute__((aligned(8)));
int ddebug_add_module(struct _ddebug *tab, unsigned int n,
const char *modname);
#if defined(CONFIG_DYNAMIC_DEBUG)
extern int ddebug_remove_module(const char *mod_name);
extern __printf(2, 3)
void __dynamic_pr_debug(struct _ddebug *descriptor, const char *fmt, ...);
extern int ddebug_dyndbg_module_param_cb(char *param, char *val,
const char *modname);
struct device;
extern __printf(3, 4)
void __dynamic_dev_dbg(struct _ddebug *descriptor, const struct device *dev,
const char *fmt, ...);
struct net_device;
extern __printf(3, 4)
void __dynamic_netdev_dbg(struct _ddebug *descriptor,
const struct net_device *dev,
const char *fmt, ...);
#define DEFINE_DYNAMIC_DEBUG_METADATA_KEY(name, fmt, key, init) \
static struct _ddebug __aligned(8) \
__attribute__((section("__verbose"))) name = { \
.modname = KBUILD_MODNAME, \
.function = __func__, \
.filename = __FILE__, \
.format = (fmt), \
.lineno = __LINE__, \
.flags = _DPRINTK_FLAGS_DEFAULT, \
dd_key_init(key, init) \
}
#ifdef HAVE_JUMP_LABEL
#define dd_key_init(key, init) key = (init)
#ifdef DEBUG
#define DEFINE_DYNAMIC_DEBUG_METADATA(name, fmt) \
DEFINE_DYNAMIC_DEBUG_METADATA_KEY(name, fmt, .key.dd_key_true, \
(STATIC_KEY_TRUE_INIT))
#define DYNAMIC_DEBUG_BRANCH(descriptor) \
static_branch_likely(&descriptor.key.dd_key_true)
#else
#define DEFINE_DYNAMIC_DEBUG_METADATA(name, fmt) \
DEFINE_DYNAMIC_DEBUG_METADATA_KEY(name, fmt, .key.dd_key_false, \
(STATIC_KEY_FALSE_INIT))
#define DYNAMIC_DEBUG_BRANCH(descriptor) \
static_branch_unlikely(&descriptor.key.dd_key_false)
#endif
#else
#define dd_key_init(key, init)
#define DEFINE_DYNAMIC_DEBUG_METADATA(name, fmt) \
DEFINE_DYNAMIC_DEBUG_METADATA_KEY(name, fmt, 0, 0)
#ifdef DEBUG
#define DYNAMIC_DEBUG_BRANCH(descriptor) \
likely(descriptor.flags & _DPRINTK_FLAGS_PRINT)
#else
#define DYNAMIC_DEBUG_BRANCH(descriptor) \
unlikely(descriptor.flags & _DPRINTK_FLAGS_PRINT)
#endif
#endif
#define dynamic_pr_debug(fmt, ...) \
do { \
DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, fmt); \
if (DYNAMIC_DEBUG_BRANCH(descriptor)) \
__dynamic_pr_debug(&descriptor, pr_fmt(fmt), \
##__VA_ARGS__); \
} while (0)
#define dynamic_dev_dbg(dev, fmt, ...) \
do { \
DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, fmt); \
if (DYNAMIC_DEBUG_BRANCH(descriptor)) \
__dynamic_dev_dbg(&descriptor, dev, fmt, \
##__VA_ARGS__); \
} while (0)
#define dynamic_netdev_dbg(dev, fmt, ...) \
do { \
DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, fmt); \
if (DYNAMIC_DEBUG_BRANCH(descriptor)) \
__dynamic_netdev_dbg(&descriptor, dev, fmt, \
##__VA_ARGS__); \
} while (0)
#define dynamic_hex_dump(prefix_str, prefix_type, rowsize, \
groupsize, buf, len, ascii) \
do { \
DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, \
__builtin_constant_p(prefix_str) ? prefix_str : "hexdump");\
if (DYNAMIC_DEBUG_BRANCH(descriptor)) \
print_hex_dump(KERN_DEBUG, prefix_str, \
prefix_type, rowsize, groupsize, \
buf, len, ascii); \
} while (0)
#else
#include <linux/string.h>
#include <linux/errno.h>
static inline int ddebug_remove_module(const char *mod)
{
return 0;
}
static inline int ddebug_dyndbg_module_param_cb(char *param, char *val,
const char *modname)
{
if (strstr(param, "dyndbg")) {
/* avoid pr_warn(), which wants pr_fmt() fully defined */
printk(KERN_WARNING "dyndbg param is supported only in "
"CONFIG_DYNAMIC_DEBUG builds\n");
return 0; /* allow and ignore */
}
return -EINVAL;
}
#define dynamic_pr_debug(fmt, ...) \
do { if (0) printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__); } while (0)
#define dynamic_dev_dbg(dev, fmt, ...) \
do { if (0) dev_printk(KERN_DEBUG, dev, fmt, ##__VA_ARGS__); } while (0)
#endif
#endif