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/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _DYNAMIC_DEBUG_H
#define _DYNAMIC_DEBUG_H
#if 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)
#define _DPRINTK_FLAGS_INCL_ANY \
(_DPRINTK_FLAGS_INCL_MODNAME | _DPRINTK_FLAGS_INCL_FUNCNAME |\
_DPRINTK_FLAGS_INCL_LINENO | _DPRINTK_FLAGS_INCL_TID)
#if defined DEBUG
#define _DPRINTK_FLAGS_DEFAULT _DPRINTK_FLAGS_PRINT
#else
#define _DPRINTK_FLAGS_DEFAULT 0
#endif
unsigned int flags:8;
#ifdef CONFIG_JUMP_LABEL
union {
struct static_key_true dd_key_true;
struct static_key_false dd_key_false;
} key;
#endif
} __attribute__((aligned(8)));
#if defined(CONFIG_DYNAMIC_DEBUG_CORE)
/* exported for module authors to exercise >control */
int dynamic_debug_exec_queries(const char *query, const char *modname);
int ddebug_add_module(struct _ddebug *tab, unsigned int n,
const char *modname);
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, ...);
struct ib_device;
extern __printf(3, 4)
void __dynamic_ibdev_dbg(struct _ddebug *descriptor,
const struct ib_device *ibdev,
const char *fmt, ...);
#define DEFINE_DYNAMIC_DEBUG_METADATA(name, fmt) \
static struct _ddebug __aligned(8) \
__section("__dyndbg") name = { \
.modname = KBUILD_MODNAME, \
.function = __func__, \
.filename = __FILE__, \
.format = (fmt), \
.lineno = __LINE__, \
.flags = _DPRINTK_FLAGS_DEFAULT, \
_DPRINTK_KEY_INIT \
}
#ifdef CONFIG_JUMP_LABEL
#ifdef DEBUG
#define _DPRINTK_KEY_INIT .key.dd_key_true = (STATIC_KEY_TRUE_INIT)
#define DYNAMIC_DEBUG_BRANCH(descriptor) \
static_branch_likely(&descriptor.key.dd_key_true)
#else
#define _DPRINTK_KEY_INIT .key.dd_key_false = (STATIC_KEY_FALSE_INIT)
#define DYNAMIC_DEBUG_BRANCH(descriptor) \
static_branch_unlikely(&descriptor.key.dd_key_false)
#endif
#else /* !CONFIG_JUMP_LABEL */
#define _DPRINTK_KEY_INIT
#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 /* CONFIG_JUMP_LABEL */
#define __dynamic_func_call(id, fmt, func, ...) do { \
DEFINE_DYNAMIC_DEBUG_METADATA(id, fmt); \
if (DYNAMIC_DEBUG_BRANCH(id)) \
func(&id, ##__VA_ARGS__); \
} while (0)
#define __dynamic_func_call_no_desc(id, fmt, func, ...) do { \
DEFINE_DYNAMIC_DEBUG_METADATA(id, fmt); \
if (DYNAMIC_DEBUG_BRANCH(id)) \
func(__VA_ARGS__); \
} while (0)
/*
* "Factory macro" for generating a call to func, guarded by a
* DYNAMIC_DEBUG_BRANCH. The dynamic debug descriptor will be
* initialized using the fmt argument. The function will be called with
* the address of the descriptor as first argument, followed by all
* the varargs. Note that fmt is repeated in invocations of this
* macro.
*/
#define _dynamic_func_call(fmt, func, ...) \
__dynamic_func_call(__UNIQUE_ID(ddebug), fmt, func, ##__VA_ARGS__)
/*
* A variant that does the same, except that the descriptor is not
* passed as the first argument to the function; it is only called
* with precisely the macro's varargs.
*/
#define _dynamic_func_call_no_desc(fmt, func, ...) \
__dynamic_func_call_no_desc(__UNIQUE_ID(ddebug), fmt, func, ##__VA_ARGS__)
#define dynamic_pr_debug(fmt, ...) \
_dynamic_func_call(fmt, __dynamic_pr_debug, \
pr_fmt(fmt), ##__VA_ARGS__)
#define dynamic_dev_dbg(dev, fmt, ...) \
_dynamic_func_call(fmt,__dynamic_dev_dbg, \
dev, fmt, ##__VA_ARGS__)
#define dynamic_netdev_dbg(dev, fmt, ...) \
_dynamic_func_call(fmt, __dynamic_netdev_dbg, \
dev, fmt, ##__VA_ARGS__)
#define dynamic_ibdev_dbg(dev, fmt, ...) \
_dynamic_func_call(fmt, __dynamic_ibdev_dbg, \
dev, fmt, ##__VA_ARGS__)
#define dynamic_hex_dump(prefix_str, prefix_type, rowsize, \
groupsize, buf, len, ascii) \
_dynamic_func_call_no_desc(__builtin_constant_p(prefix_str) ? prefix_str : "hexdump", \
print_hex_dump, \
KERN_DEBUG, prefix_str, prefix_type, \
rowsize, groupsize, buf, len, ascii)
#else /* !CONFIG_DYNAMIC_DEBUG_CORE */
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/printk.h>
static inline int ddebug_add_module(struct _ddebug *tab, unsigned int n,
const char *modname)
{
return 0;
}
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)
#define dynamic_hex_dump(prefix_str, prefix_type, rowsize, \
groupsize, buf, len, ascii) \
do { if (0) \
print_hex_dump(KERN_DEBUG, prefix_str, prefix_type, \
rowsize, groupsize, buf, len, ascii); \
} while (0)
static inline int dynamic_debug_exec_queries(const char *query, const char *modname)
{
pr_warn("kernel not built with CONFIG_DYNAMIC_DEBUG_CORE\n");
return 0;
}
#endif /* !CONFIG_DYNAMIC_DEBUG_CORE */
#endif
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