454 строки
13 KiB
C
454 строки
13 KiB
C
/*
|
|
* 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__ */
|