linux-stable/include/linux/dynamic_debug.h
Thomas Weißschuh 31ed379b7c dyndbg: add source filename to prefix
Printing the line number without the file is of limited usefulness.

Knowing the filename also makes it also easier to relate the logged
information to the controlfile.

Example:

    # modprobe test_dynamic_debug
    # echo 'file test_dynamic_debug.c =pfsl' > /proc/dynamic_debug/control
    # echo 1 > /sys/module/test_dynamic_debug/parameters/do_prints
    # dmesg | tail -2
    [   71.802212] do_cats:lib/test_dynamic_debug.c:103: test_dd: doing categories
    [   71.802227] do_levels:lib/test_dynamic_debug.c:123: test_dd: doing levels

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Acked-by: Jim Cromie <jim.cromie@gmail.com>
Acked-by: Jason Baron <jbaron@akamai.com>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Link: https://lore.kernel.org/r/20230709-dyndbg-filename-v2-3-fd83beef0925@weissschuh.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-04 15:28:41 +02:00

354 lines
11 KiB
C

/* 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
#include <linux/build_bug.h>
/*
* 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;
#define CLS_BITS 6
unsigned int class_id:CLS_BITS;
#define _DPRINTK_CLASS_DFLT ((1 << CLS_BITS) - 1)
/*
* 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_SOURCENAME (1<<5)
#define _DPRINTK_FLAGS_INCL_ANY \
(_DPRINTK_FLAGS_INCL_MODNAME | _DPRINTK_FLAGS_INCL_FUNCNAME |\
_DPRINTK_FLAGS_INCL_LINENO | _DPRINTK_FLAGS_INCL_TID |\
_DPRINTK_FLAGS_INCL_SOURCENAME)
#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)));
enum class_map_type {
DD_CLASS_TYPE_DISJOINT_BITS,
/**
* DD_CLASS_TYPE_DISJOINT_BITS: classes are independent, one per bit.
* expecting hex input. Built for drm.debug, basis for other types.
*/
DD_CLASS_TYPE_LEVEL_NUM,
/**
* DD_CLASS_TYPE_LEVEL_NUM: input is numeric level, 0-N.
* N turns on just bits N-1 .. 0, so N=0 turns all bits off.
*/
DD_CLASS_TYPE_DISJOINT_NAMES,
/**
* DD_CLASS_TYPE_DISJOINT_NAMES: input is a CSV of [+-]CLASS_NAMES,
* classes are independent, like _DISJOINT_BITS.
*/
DD_CLASS_TYPE_LEVEL_NAMES,
/**
* DD_CLASS_TYPE_LEVEL_NAMES: input is a CSV of [+-]CLASS_NAMES,
* intended for names like: INFO,DEBUG,TRACE, with a module prefix
* avoid EMERG,ALERT,CRIT,ERR,WARNING: they're not debug
*/
};
struct ddebug_class_map {
struct list_head link;
struct module *mod;
const char *mod_name; /* needed for builtins */
const char **class_names;
const int length;
const int base; /* index of 1st .class_id, allows split/shared space */
enum class_map_type map_type;
};
/**
* DECLARE_DYNDBG_CLASSMAP - declare classnames known by a module
* @_var: a struct ddebug_class_map, passed to module_param_cb
* @_type: enum class_map_type, chooses bits/verbose, numeric/symbolic
* @_base: offset of 1st class-name. splits .class_id space
* @classes: class-names used to control class'd prdbgs
*/
#define DECLARE_DYNDBG_CLASSMAP(_var, _maptype, _base, ...) \
static const char *_var##_classnames[] = { __VA_ARGS__ }; \
static struct ddebug_class_map __aligned(8) __used \
__section("__dyndbg_classes") _var = { \
.mod = THIS_MODULE, \
.mod_name = KBUILD_MODNAME, \
.base = _base, \
.map_type = _maptype, \
.length = NUM_TYPE_ARGS(char*, __VA_ARGS__), \
.class_names = _var##_classnames, \
}
#define NUM_TYPE_ARGS(eltype, ...) \
(sizeof((eltype[]){__VA_ARGS__}) / sizeof(eltype))
/* encapsulate linker provided built-in (or module) dyndbg data */
struct _ddebug_info {
struct _ddebug *descs;
struct ddebug_class_map *classes;
unsigned int num_descs;
unsigned int num_classes;
};
struct ddebug_class_param {
union {
unsigned long *bits;
unsigned int *lvl;
};
char flags[8];
const struct ddebug_class_map *map;
};
/*
* pr_debug() and friends are globally enabled or modules have selectively
* enabled them.
*/
#if defined(CONFIG_DYNAMIC_DEBUG) || \
(defined(CONFIG_DYNAMIC_DEBUG_CORE) && defined(DYNAMIC_DEBUG_MODULE))
extern __printf(2, 3)
void __dynamic_pr_debug(struct _ddebug *descriptor, const char *fmt, ...);
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_CLS(name, cls, fmt) \
static struct _ddebug __aligned(8) \
__section("__dyndbg") name = { \
.modname = KBUILD_MODNAME, \
.function = __func__, \
.filename = __FILE__, \
.format = (fmt), \
.lineno = __LINE__, \
.flags = _DPRINTK_FLAGS_DEFAULT, \
.class_id = cls, \
_DPRINTK_KEY_INIT \
}; \
BUILD_BUG_ON_MSG(cls > _DPRINTK_CLASS_DFLT, \
"classid value overflow")
#define DEFINE_DYNAMIC_DEBUG_METADATA(name, fmt) \
DEFINE_DYNAMIC_DEBUG_METADATA_CLS(name, _DPRINTK_CLASS_DFLT, fmt)
#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 */
/*
* Factory macros: ($prefix)dynamic_func_call($suffix)
*
* Lower layer (with __ prefix) gets the callsite metadata, and wraps
* the func inside a debug-branch/static-key construct. Upper layer
* (with _ prefix) does the UNIQUE_ID once, so that lower can ref the
* name/label multiple times, and tie the elements together.
* Multiple flavors:
* (|_cls): adds in _DPRINT_CLASS_DFLT as needed
* (|_no_desc): former gets callsite descriptor as 1st arg (for prdbgs)
*/
#define __dynamic_func_call_cls(id, cls, fmt, func, ...) do { \
DEFINE_DYNAMIC_DEBUG_METADATA_CLS(id, cls, fmt); \
if (DYNAMIC_DEBUG_BRANCH(id)) \
func(&id, ##__VA_ARGS__); \
} while (0)
#define __dynamic_func_call(id, fmt, func, ...) \
__dynamic_func_call_cls(id, _DPRINTK_CLASS_DFLT, fmt, \
func, ##__VA_ARGS__)
#define __dynamic_func_call_cls_no_desc(id, cls, fmt, func, ...) do { \
DEFINE_DYNAMIC_DEBUG_METADATA_CLS(id, cls, fmt); \
if (DYNAMIC_DEBUG_BRANCH(id)) \
func(__VA_ARGS__); \
} while (0)
#define __dynamic_func_call_no_desc(id, fmt, func, ...) \
__dynamic_func_call_cls_no_desc(id, _DPRINTK_CLASS_DFLT, \
fmt, func, ##__VA_ARGS__)
/*
* "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_cls(cls, fmt, func, ...) \
__dynamic_func_call_cls(__UNIQUE_ID(ddebug), cls, fmt, func, ##__VA_ARGS__)
#define _dynamic_func_call(fmt, func, ...) \
_dynamic_func_call_cls(_DPRINTK_CLASS_DFLT, 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_cls_no_desc(cls, fmt, func, ...) \
__dynamic_func_call_cls_no_desc(__UNIQUE_ID(ddebug), cls, fmt, \
func, ##__VA_ARGS__)
#define _dynamic_func_call_no_desc(fmt, func, ...) \
_dynamic_func_call_cls_no_desc(_DPRINTK_CLASS_DFLT, fmt, \
func, ##__VA_ARGS__)
#define dynamic_pr_debug_cls(cls, fmt, ...) \
_dynamic_func_call_cls(cls, fmt, __dynamic_pr_debug, \
pr_fmt(fmt), ##__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)
/* for test only, generally expect drm.debug style macro wrappers */
#define __pr_debug_cls(cls, fmt, ...) do { \
BUILD_BUG_ON_MSG(!__builtin_constant_p(cls), \
"expecting constant class int/enum"); \
dynamic_pr_debug_cls(cls, fmt, ##__VA_ARGS__); \
} while (0)
#else /* !(CONFIG_DYNAMIC_DEBUG || (CONFIG_DYNAMIC_DEBUG_CORE && DYNAMIC_DEBUG_MODULE)) */
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/printk.h>
#define DEFINE_DYNAMIC_DEBUG_METADATA(name, fmt)
#define DYNAMIC_DEBUG_BRANCH(descriptor) false
#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)
#endif /* CONFIG_DYNAMIC_DEBUG || (CONFIG_DYNAMIC_DEBUG_CORE && DYNAMIC_DEBUG_MODULE) */
#ifdef CONFIG_DYNAMIC_DEBUG_CORE
extern int ddebug_dyndbg_module_param_cb(char *param, char *val,
const char *modname);
struct kernel_param;
int param_set_dyndbg_classes(const char *instr, const struct kernel_param *kp);
int param_get_dyndbg_classes(char *buffer, const struct kernel_param *kp);
#else
static inline int ddebug_dyndbg_module_param_cb(char *param, char *val,
const char *modname)
{
if (!strcmp(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;
}
struct kernel_param;
static inline int param_set_dyndbg_classes(const char *instr, const struct kernel_param *kp)
{ return 0; }
static inline int param_get_dyndbg_classes(char *buffer, const struct kernel_param *kp)
{ return 0; }
#endif
extern const struct kernel_param_ops param_ops_dyndbg_classes;
#endif /* _DYNAMIC_DEBUG_H */