include/linux/wimax/debug.h - kernel/msm-4.9 - Gitiles

 /*
  * Linux WiMAX
  * Collection of tools to manage debug operations.
  *
  *
  * Copyright (C) 2005-2007 Intel Corporation
  * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License version
  * 2 as published by the Free Software Foundation.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  * 02110-1301, USA.
  *
  *
  * Don't #include this file directly, read on!
  *
  *
  * EXECUTING DEBUGGING ACTIONS OR NOT
  *
  * The main thing this framework provides is decission power to take a
  * debug action (like printing a message) if the current debug level
  * allows it.
  *
  * The decission power is at two levels: at compile-time (what does
  * not make it is compiled out) and at run-time. The run-time
  * selection is done per-submodule (as they are declared by the user
  * of the framework).
  *
  * A call to d_test(L) (L being the target debug level) returns true
  * if the action should be taken because the current debug levels
  * allow it (both compile and run time).
  *
  * It follows that a call to d_test() that can be determined to be
  * always false at compile time will get the code depending on it
  * compiled out by optimization.
  *
  *
  * DEBUG LEVELS
  *
  * It is up to the caller to define how much a debugging level is.
  *
  * Convention sets 0 as "no debug" (so an action marked as debug level 0
  * will always be taken). The increasing debug levels are used for
  * increased verbosity.
  *
  *
  * USAGE
  *
  * Group the code in modules and submodules inside each module [which
  * in most cases maps to Linux modules and .c files that compose
  * those].
  *
  *
  * For each module, there is:
  *
  *  - a MODULENAME (single word, legal C identifier)
  *
  *  - a debug-levels.h header file that declares the list of
  *    submodules and that is included by all .c files that use
  *    the debugging tools. The file name can be anything.
  *
  *  - some (optional) .c code to manipulate the runtime debug levels
  *    through debugfs.
  *
  * The debug-levels.h file would look like:
  *
  *     #ifndef __debug_levels__h__
  *     #define __debug_levels__h__
  *
  *     #define D_MODULENAME modulename
  *     #define D_MASTER 10
  *
  *     #include <linux/wimax/debug.h>
  *
  *     enum d_module {
  *             D_SUBMODULE_DECLARE(submodule_1),
  *             D_SUBMODULE_DECLARE(submodule_2),
  *             ...
  *             D_SUBMODULE_DECLARE(submodule_N)
  *     };
  *
  *     #endif
  *
  * D_MASTER is the maximum compile-time debug level; any debug actions
  * above this will be out. D_MODULENAME is the module name (legal C
  * identifier), which has to be unique for each module (to avoid
  * namespace collisions during linkage). Note those #defines need to
  * be done before #including debug.h
  *
  * We declare N different submodules whose debug level can be
  * independently controlled during runtime.
  *
  * In a .c file of the module (and only in one of them), define the
  * following code:
  *
  *     struct d_level D_LEVEL[] = {
  *             D_SUBMODULE_DEFINE(submodule_1),
  *             D_SUBMODULE_DEFINE(submodule_2),
  *             ...
  *             D_SUBMODULE_DEFINE(submodule_N),
  *     };
  *     size_t D_LEVEL_SIZE = ARRAY_SIZE(D_LEVEL);
  *
  * Externs for d_level_MODULENAME and d_level_size_MODULENAME are used
  * and declared in this file using the D_LEVEL and D_LEVEL_SIZE macros
  * #defined also in this file.
  *
  * To manipulate from user space the levels, create a debugfs dentry
  * and then register each submodule with:
  *
  *     result = d_level_register_debugfs("PREFIX_", submodule_X, parent);
  *     if (result < 0)
  *            goto error;
  *
  * Where PREFIX_ is a name of your chosing. This will create debugfs
  * file with a single numeric value that can be use to tweak it. To
  * remove the entires, just use debugfs_remove_recursive() on 'parent'.
  *
  * NOTE: remember that even if this will show attached to some
  *     particular instance of a device, the settings are *global*.
  *
  *
  * On each submodule (for example, .c files), the debug infrastructure
  * should be included like this:
  *
  *     #define D_SUBMODULE submodule_x     // matches one in debug-levels.h
  *     #include "debug-levels.h"
  *
  * after #including all your include files.
  *
  *
  * Now you can use the d_*() macros below [d_test(), d_fnstart(),
  * d_fnend(), d_printf(), d_dump()].
  *
  * If their debug level is greater than D_MASTER, they will be
  * compiled out.
  *
  * If their debug level is lower or equal than D_MASTER but greater
  * than the current debug level of their submodule, they'll be
  * ignored.
  *
  * Otherwise, the action will be performed.
  */
 #ifndef __debug__h__
 #define __debug__h__

 #include <linux/types.h>
 #include <linux/device.h>


 /* Backend stuff */

 /*
  * Debug backend: generate a message header from a 'struct device'
  *
  * @head: buffer where to place the header
  * @head_size: length of @head
  * @dev: pointer to device used to generate a header from. If NULL,
  *     an empty ("") header is generated.
  */
 static inline
 void __d_head(char *head, size_t head_size,
 	      struct device *dev)
 {
 	if (dev == NULL)
 		head[0] = 0;
 	else if ((unsigned long)dev < 4096) {
 		printk(KERN_ERR "E: Corrupt dev %p\n", dev);
 		WARN_ON(1);
 	} else
 		snprintf(head, head_size, "%s %s: ",
 			 dev_driver_string(dev), dev_name(dev));
 }


 /*
  * Debug backend: log some message if debugging is enabled
  *
  * @l: intended debug level
  * @tag: tag to prefix the message with
  * @dev: 'struct device' associated to this message
  * @f: printf-like format and arguments
  *
  * Note this is optimized out if it doesn't pass the compile-time
  * check; however, it is *always* compiled. This is useful to make
  * sure the printf-like formats and variables are always checked and
  * they don't get bit rot if you have all the debugging disabled.
  */
 #define _d_printf(l, tag, dev, f, a...)					\
 do {									\
 	char head[64];							\
 	if (!d_test(l))							\
 		break;							\
 	__d_head(head, sizeof(head), dev);				\
 	printk(KERN_ERR "%s%s%s: " f, head, __func__, tag, ##a);	\
 } while (0)


 /*
  * CPP sintatic sugar to generate A_B like symbol names when one of
  * the arguments is a a preprocessor #define.
  */
 #define __D_PASTE__(varname, modulename) varname##_##modulename
 #define __D_PASTE(varname, modulename) (__D_PASTE__(varname, modulename))
 #define _D_SUBMODULE_INDEX(_name) (D_SUBMODULE_DECLARE(_name))


 /*
  * Store a submodule's runtime debug level and name
  */
 struct d_level {
 	u8 level;
 	const char *name;
 };


 /*
  * List of available submodules and their debug levels
  *
  * We call them d_level_MODULENAME and d_level_size_MODULENAME; the
  * macros D_LEVEL and D_LEVEL_SIZE contain the name already for
  * convenience.
  *
  * This array and the size are defined on some .c file that is part of
  * the current module.
  */
 #define D_LEVEL __D_PASTE(d_level, D_MODULENAME)
 #define D_LEVEL_SIZE __D_PASTE(d_level_size, D_MODULENAME)

 extern struct d_level D_LEVEL[];
 extern size_t D_LEVEL_SIZE;


 /*
  * Frontend stuff
  *
  *
  * Stuff you need to declare prior to using the actual "debug" actions
  * (defined below).
  */

 #ifndef D_MODULENAME
 #error D_MODULENAME is not defined in your debug-levels.h file
 /**
  * D_MODULE - Name of the current module
  *
  * #define in your module's debug-levels.h, making sure it is
  * unique. This has to be a legal C identifier.
  */
 #define D_MODULENAME undefined_modulename
 #endif


 #ifndef D_MASTER
 #warning D_MASTER not defined, but debug.h included! [see docs]
 /**
  * D_MASTER - Compile time maximum debug level
  *
  * #define in your debug-levels.h file to the maximum debug level the
  * runtime code will be allowed to have. This allows you to provide a
  * main knob.
  *
  * Anything above that level will be optimized out of the compile.
  *
  * Defaults to zero (no debug code compiled in).
  *
  * Maximum one definition per module (at the debug-levels.h file).
  */
 #define D_MASTER 0
 #endif

 #ifndef D_SUBMODULE
 #error D_SUBMODULE not defined, but debug.h included! [see docs]
 /**
  * D_SUBMODULE - Name of the current submodule
  *
  * #define in your submodule .c file before #including debug-levels.h
  * to the name of the current submodule as previously declared and
  * defined with D_SUBMODULE_DECLARE() (in your module's
  * debug-levels.h) and D_SUBMODULE_DEFINE().
  *
  * This is used to provide runtime-control over the debug levels.
  *
  * Maximum one per .c file! Can be shared among different .c files
  * (meaning they belong to the same submodule categorization).
  */
 #define D_SUBMODULE undefined_module
 #endif


 /**
  * D_SUBMODULE_DECLARE - Declare a submodule for runtime debug level control
  *
  * @_name: name of the submodule, restricted to the chars that make up a
  *     valid C identifier ([a-zA-Z0-9_]).
  *
  * Declare in the module's debug-levels.h header file as:
  *
  * enum d_module {
  *         D_SUBMODULE_DECLARE(submodule_1),
  *         D_SUBMODULE_DECLARE(submodule_2),
  *         D_SUBMODULE_DECLARE(submodule_3),
  * };
  *
  * Some corresponding .c file needs to have a matching
  * D_SUBMODULE_DEFINE().
  */
 #define D_SUBMODULE_DECLARE(_name) __D_SUBMODULE_##_name


 /**
  * D_SUBMODULE_DEFINE - Define a submodule for runtime debug level control
  *
  * @_name: name of the submodule, restricted to the chars that make up a
  *     valid C identifier ([a-zA-Z0-9_]).
  *
  * Use once per module (in some .c file) as:
  *
  * static
  * struct d_level d_level_SUBMODULENAME[] = {
  *         D_SUBMODULE_DEFINE(submodule_1),
  *         D_SUBMODULE_DEFINE(submodule_2),
  *         D_SUBMODULE_DEFINE(submodule_3),
  * };
  * size_t d_level_size_SUBDMODULENAME = ARRAY_SIZE(d_level_SUBDMODULENAME);
  *
  * Matching D_SUBMODULE_DECLARE()s have to be present in a
  * debug-levels.h header file.
  */
 #define D_SUBMODULE_DEFINE(_name)		\
 [__D_SUBMODULE_##_name] = {			\
 	.level = 0,				\
 	.name = #_name				\
 }


 /* The actual "debug" operations */


 /**
  * d_test - Returns true if debugging should be enabled
  *
  * @l: intended debug level (unsigned)
  *
  * If the master debug switch is enabled and the current settings are
  * higher or equal to the requested level, then debugging
  * output/actions should be enabled.
  *
  * NOTE:
  *
  * This needs to be coded so that it can be evaluated in compile
  * time; this is why the ugly BUG_ON() is placed in there, so the
  * D_MASTER evaluation compiles all out if it is compile-time false.
  */
 #define d_test(l)							\
 ({									\
 	unsigned __l = l;	/* type enforcer */			\
 	(D_MASTER) >= __l						\
 	&& ({								\
 		BUG_ON(_D_SUBMODULE_INDEX(D_SUBMODULE) >= D_LEVEL_SIZE);\
 		D_LEVEL[_D_SUBMODULE_INDEX(D_SUBMODULE)].level >= __l;	\
 	});								\
 })


 /**
  * d_fnstart - log message at function start if debugging enabled
  *
  * @l: intended debug level
  * @_dev: 'struct device' pointer, NULL if none (for context)
  * @f: printf-like format and arguments
  */
 #define d_fnstart(l, _dev, f, a...) _d_printf(l, " FNSTART", _dev, f, ## a)


 /**
  * d_fnend - log message at function end if debugging enabled
  *
  * @l: intended debug level
  * @_dev: 'struct device' pointer, NULL if none (for context)
  * @f: printf-like format and arguments
  */
 #define d_fnend(l, _dev, f, a...) _d_printf(l, " FNEND", _dev, f, ## a)


 /**
  * d_printf - log message if debugging enabled
  *
  * @l: intended debug level
  * @_dev: 'struct device' pointer, NULL if none (for context)
  * @f: printf-like format and arguments
  */
 #define d_printf(l, _dev, f, a...) _d_printf(l, "", _dev, f, ## a)


 /**
  * d_dump - log buffer hex dump if debugging enabled
  *
  * @l: intended debug level
  * @_dev: 'struct device' pointer, NULL if none (for context)
  * @f: printf-like format and arguments
  */
 #define d_dump(l, dev, ptr, size)			\
 do {							\
 	char head[64];					\
 	if (!d_test(l))					\
 		break;					\
 	__d_head(head, sizeof(head), dev);		\
 	print_hex_dump(KERN_ERR, head, 0, 16, 1,	\
 		       ((void *) ptr), (size), 0);	\
 } while (0)


 /**
  * Export a submodule's debug level over debugfs as PREFIXSUBMODULE
  *
  * @prefix: string to prefix the name with
  * @submodule: name of submodule (not a string, just the name)
  * @dentry: debugfs parent dentry
  *
  * Returns: 0 if ok, < 0 errno on error.
  *
  * For removing, just use debugfs_remove_recursive() on the parent.
  */
 #define d_level_register_debugfs(prefix, name, parent)			\
 ({									\
 	int rc;								\
 	struct dentry *fd;						\
 	struct dentry *verify_parent_type = parent;			\
 	fd = debugfs_create_u8(						\
 		prefix #name, 0600, verify_parent_type,			\
 		&(D_LEVEL[__D_SUBMODULE_ ## name].level));		\
 	rc = PTR_ERR(fd);						\
 	if (IS_ERR(fd) && rc != -ENODEV)				\
 		printk(KERN_ERR "%s: Can't create debugfs entry %s: "	\
 		       "%d\n", __func__, prefix #name, rc);		\
 	else								\
 		rc = 0;							\
 	rc;								\
 })


 #endif /* #ifndef __debug__h__ */
	/*
	* Linux WiMAX
	* Collection of tools to manage debug operations.
	*
	*
	* Copyright (C) 2005-2007 Intel Corporation
	* Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
	*
	* This program is free software; you can redistribute it and/or
	* modify it under the terms of the GNU General Public License version
	* 2 as published by the Free Software Foundation.
	*
	* This program is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	* GNU General Public License for more details.
	*
	* You should have received a copy of the GNU General Public License
	* along with this program; if not, write to the Free Software
	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
	* 02110-1301, USA.
	*
	*
	* Don't #include this file directly, read on!
	*
	*
	* EXECUTING DEBUGGING ACTIONS OR NOT
	*
	* The main thing this framework provides is decission power to take a
	* debug action (like printing a message) if the current debug level
	* allows it.
	*
	* The decission power is at two levels: at compile-time (what does
	* not make it is compiled out) and at run-time. The run-time
	* selection is done per-submodule (as they are declared by the user
	* of the framework).
	*
	* A call to d_test(L) (L being the target debug level) returns true
	* if the action should be taken because the current debug levels
	* allow it (both compile and run time).
	*
	* It follows that a call to d_test() that can be determined to be
	* always false at compile time will get the code depending on it
	* compiled out by optimization.
	*
	*
	* DEBUG LEVELS
	*
	* It is up to the caller to define how much a debugging level is.
	*
	* Convention sets 0 as "no debug" (so an action marked as debug level 0
	* will always be taken). The increasing debug levels are used for
	* increased verbosity.
	*
	*
	* USAGE
	*
	* Group the code in modules and submodules inside each module [which
	* in most cases maps to Linux modules and .c files that compose
	* those].
	*
	*
	* For each module, there is:
	*
	* - a MODULENAME (single word, legal C identifier)
	*
	* - a debug-levels.h header file that declares the list of
	* submodules and that is included by all .c files that use
	* the debugging tools. The file name can be anything.
	*
	* - some (optional) .c code to manipulate the runtime debug levels
	* through debugfs.
	*
	* The debug-levels.h file would look like:
	*
	* #ifndef __debug_levels__h__
	* #define __debug_levels__h__
	*
	* #define D_MODULENAME modulename
	* #define D_MASTER 10
	*
	* #include <linux/wimax/debug.h>
	*
	* enum d_module {
	* D_SUBMODULE_DECLARE(submodule_1),
	* D_SUBMODULE_DECLARE(submodule_2),
	* ...
	* D_SUBMODULE_DECLARE(submodule_N)
	* };
	*
	* #endif
	*
	* D_MASTER is the maximum compile-time debug level; any debug actions
	* above this will be out. D_MODULENAME is the module name (legal C
	* identifier), which has to be unique for each module (to avoid
	* namespace collisions during linkage). Note those #defines need to
	* be done before #including debug.h
	*
	* We declare N different submodules whose debug level can be
	* independently controlled during runtime.
	*
	* In a .c file of the module (and only in one of them), define the
	* following code:
	*
	* struct d_level D_LEVEL[] = {
	* D_SUBMODULE_DEFINE(submodule_1),
	* D_SUBMODULE_DEFINE(submodule_2),
	* ...
	* D_SUBMODULE_DEFINE(submodule_N),
	* };
	* size_t D_LEVEL_SIZE = ARRAY_SIZE(D_LEVEL);
	*
	* Externs for d_level_MODULENAME and d_level_size_MODULENAME are used
	* and declared in this file using the D_LEVEL and D_LEVEL_SIZE macros
	* #defined also in this file.
	*
	* To manipulate from user space the levels, create a debugfs dentry
	* and then register each submodule with:
	*
	* result = d_level_register_debugfs("PREFIX_", submodule_X, parent);
	* if (result < 0)
	* goto error;
	*
	* Where PREFIX_ is a name of your chosing. This will create debugfs
	* file with a single numeric value that can be use to tweak it. To
	* remove the entires, just use debugfs_remove_recursive() on 'parent'.
	*
	* NOTE: remember that even if this will show attached to some
	* particular instance of a device, the settings are global.
	*
	*
	* On each submodule (for example, .c files), the debug infrastructure
	* should be included like this:
	*
	* #define D_SUBMODULE submodule_x // matches one in debug-levels.h
	* #include "debug-levels.h"
	*
	* after #including all your include files.
	*
	*
	* Now you can use the d_*() macros below [d_test(), d_fnstart(),
	* d_fnend(), d_printf(), d_dump()].
	*
	* If their debug level is greater than D_MASTER, they will be
	* compiled out.
	*
	* If their debug level is lower or equal than D_MASTER but greater
	* than the current debug level of their submodule, they'll be
	* ignored.
	*
	* Otherwise, the action will be performed.
	*/
	#ifndef __debug__h__
	#define __debug__h__

	#include <linux/types.h>
	#include <linux/device.h>


	/* Backend stuff */

	/*
	* Debug backend: generate a message header from a 'struct device'
	*
	* @head: buffer where to place the header
	* @head_size: length of @head
	* @dev: pointer to device used to generate a header from. If NULL,
	* an empty ("") header is generated.
	*/
	static inline
	void __d_head(char *head, size_t head_size,
	struct device *dev)
	{
	if (dev == NULL)
	head[0] = 0;
	else if ((unsigned long)dev < 4096) {
	printk(KERN_ERR "E: Corrupt dev %p\n", dev);
	WARN_ON(1);
	} else
	snprintf(head, head_size, "%s %s: ",
	dev_driver_string(dev), dev_name(dev));
	}


	/*
	* Debug backend: log some message if debugging is enabled
	*
	* @l: intended debug level
	* @tag: tag to prefix the message with
	* @dev: 'struct device' associated to this message
	* @f: printf-like format and arguments
	*
	* Note this is optimized out if it doesn't pass the compile-time
	* check; however, it is always compiled. This is useful to make
	* sure the printf-like formats and variables are always checked and
	* they don't get bit rot if you have all the debugging disabled.
	*/
	#define _d_printf(l, tag, dev, f, a...) \
	do { \
	char head[64]; \
	if (!d_test(l)) \
	break; \
	__d_head(head, sizeof(head), dev); \
	printk(KERN_ERR "%s%s%s: " f, head, __func__, tag, ##a); \
	} while (0)


	/*
	* CPP sintatic sugar to generate A_B like symbol names when one of
	* the arguments is a a preprocessor #define.
	*/
	#define __D_PASTE__(varname, modulename) varname##_##modulename
	#define __D_PASTE(varname, modulename) (__D_PASTE__(varname, modulename))
	#define _D_SUBMODULE_INDEX(_name) (D_SUBMODULE_DECLARE(_name))


	/*
	* Store a submodule's runtime debug level and name
	*/
	struct d_level {
	u8 level;
	const char *name;
	};


	/*
	* List of available submodules and their debug levels
	*
	* We call them d_level_MODULENAME and d_level_size_MODULENAME; the
	* macros D_LEVEL and D_LEVEL_SIZE contain the name already for
	* convenience.
	*
	* This array and the size are defined on some .c file that is part of
	* the current module.
	*/
	#define D_LEVEL __D_PASTE(d_level, D_MODULENAME)
	#define D_LEVEL_SIZE __D_PASTE(d_level_size, D_MODULENAME)

	extern struct d_level D_LEVEL[];
	extern size_t D_LEVEL_SIZE;


	/*
	* Frontend stuff
	*
	*
	* Stuff you need to declare prior to using the actual "debug" actions
	* (defined below).
	*/

	#ifndef D_MODULENAME
	#error D_MODULENAME is not defined in your debug-levels.h file
	/**
	* D_MODULE - Name of the current module
	*
	* #define in your module's debug-levels.h, making sure it is
	* unique. This has to be a legal C identifier.
	*/
	#define D_MODULENAME undefined_modulename
	#endif


	#ifndef D_MASTER
	#warning D_MASTER not defined, but debug.h included! [see docs]
	/**
	* D_MASTER - Compile time maximum debug level
	*
	* #define in your debug-levels.h file to the maximum debug level the
	* runtime code will be allowed to have. This allows you to provide a
	* main knob.
	*
	* Anything above that level will be optimized out of the compile.
	*
	* Defaults to zero (no debug code compiled in).
	*
	* Maximum one definition per module (at the debug-levels.h file).
	*/
	#define D_MASTER 0
	#endif

	#ifndef D_SUBMODULE
	#error D_SUBMODULE not defined, but debug.h included! [see docs]
	/**
	* D_SUBMODULE - Name of the current submodule
	*
	* #define in your submodule .c file before #including debug-levels.h
	* to the name of the current submodule as previously declared and
	* defined with D_SUBMODULE_DECLARE() (in your module's
	* debug-levels.h) and D_SUBMODULE_DEFINE().
	*
	* This is used to provide runtime-control over the debug levels.
	*
	* Maximum one per .c file! Can be shared among different .c files
	* (meaning they belong to the same submodule categorization).
	*/
	#define D_SUBMODULE undefined_module
	#endif


	/**
	* D_SUBMODULE_DECLARE - Declare a submodule for runtime debug level control
	*
	* @_name: name of the submodule, restricted to the chars that make up a
	* valid C identifier ([a-zA-Z0-9_]).
	*
	* Declare in the module's debug-levels.h header file as:
	*
	* enum d_module {
	* D_SUBMODULE_DECLARE(submodule_1),
	* D_SUBMODULE_DECLARE(submodule_2),
	* D_SUBMODULE_DECLARE(submodule_3),
	* };
	*
	* Some corresponding .c file needs to have a matching
	* D_SUBMODULE_DEFINE().
	*/
	#define D_SUBMODULE_DECLARE(_name) __D_SUBMODULE_##_name


	/**
	* D_SUBMODULE_DEFINE - Define a submodule for runtime debug level control
	*
	* @_name: name of the submodule, restricted to the chars that make up a
	* valid C identifier ([a-zA-Z0-9_]).
	*
	* Use once per module (in some .c file) as:
	*
	* static
	* struct d_level d_level_SUBMODULENAME[] = {
	* D_SUBMODULE_DEFINE(submodule_1),
	* D_SUBMODULE_DEFINE(submodule_2),
	* D_SUBMODULE_DEFINE(submodule_3),
	* };
	* size_t d_level_size_SUBDMODULENAME = ARRAY_SIZE(d_level_SUBDMODULENAME);
	*
	* Matching D_SUBMODULE_DECLARE()s have to be present in a
	* debug-levels.h header file.
	*/
	#define D_SUBMODULE_DEFINE(_name) \
	[__D_SUBMODULE_##_name] = { \
	.level = 0, \
	.name = #_name \
	}



	/* The actual "debug" operations */


	/**
	* d_test - Returns true if debugging should be enabled
	*
	* @l: intended debug level (unsigned)
	*
	* If the master debug switch is enabled and the current settings are
	* higher or equal to the requested level, then debugging
	* output/actions should be enabled.
	*
	* NOTE:
	*
	* This needs to be coded so that it can be evaluated in compile
	* time; this is why the ugly BUG_ON() is placed in there, so the
	* D_MASTER evaluation compiles all out if it is compile-time false.
	*/
	#define d_test(l) \
	({ \
	unsigned __l = l; /* type enforcer */ \
	(D_MASTER) >= __l \
	&& ({ \
	BUG_ON(_D_SUBMODULE_INDEX(D_SUBMODULE) >= D_LEVEL_SIZE);\
	D_LEVEL[_D_SUBMODULE_INDEX(D_SUBMODULE)].level >= __l; \
	}); \
	})


	/**
	* d_fnstart - log message at function start if debugging enabled
	*
	* @l: intended debug level
	* @_dev: 'struct device' pointer, NULL if none (for context)
	* @f: printf-like format and arguments
	*/
	#define d_fnstart(l, _dev, f, a...) _d_printf(l, " FNSTART", _dev, f, ## a)


	/**
	* d_fnend - log message at function end if debugging enabled
	*
	* @l: intended debug level
	* @_dev: 'struct device' pointer, NULL if none (for context)
	* @f: printf-like format and arguments
	*/
	#define d_fnend(l, _dev, f, a...) _d_printf(l, " FNEND", _dev, f, ## a)


	/**
	* d_printf - log message if debugging enabled
	*
	* @l: intended debug level
	* @_dev: 'struct device' pointer, NULL if none (for context)
	* @f: printf-like format and arguments
	*/
	#define d_printf(l, _dev, f, a...) _d_printf(l, "", _dev, f, ## a)


	/**
	* d_dump - log buffer hex dump if debugging enabled
	*
	* @l: intended debug level
	* @_dev: 'struct device' pointer, NULL if none (for context)
	* @f: printf-like format and arguments
	*/
	#define d_dump(l, dev, ptr, size) \
	do { \
	char head[64]; \
	if (!d_test(l)) \
	break; \
	__d_head(head, sizeof(head), dev); \
	print_hex_dump(KERN_ERR, head, 0, 16, 1, \
	((void *) ptr), (size), 0); \
	} while (0)


	/**
	* Export a submodule's debug level over debugfs as PREFIXSUBMODULE
	*
	* @prefix: string to prefix the name with
	* @submodule: name of submodule (not a string, just the name)
	* @dentry: debugfs parent dentry
	*
	* Returns: 0 if ok, < 0 errno on error.
	*
	* For removing, just use debugfs_remove_recursive() on the parent.
	*/
	#define d_level_register_debugfs(prefix, name, parent) \
	({ \
	int rc; \
	struct dentry *fd; \
	struct dentry *verify_parent_type = parent; \
	fd = debugfs_create_u8( \
	prefix #name, 0600, verify_parent_type, \
	&(D_LEVEL[__D_SUBMODULE_ ## name].level)); \
	rc = PTR_ERR(fd); \
	if (IS_ERR(fd) && rc != -ENODEV) \
	printk(KERN_ERR "%s: Can't create debugfs entry %s: " \
	"%d\n", __func__, prefix #name, rc); \
	else \
	rc = 0; \
	rc; \
	})


	#endif /* #ifndef __debug__h__ */