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#ifndef _DYNAMIC_DEBUG_H
#define _DYNAMIC_DEBUG_H
#include <linux/jump_label.h>
/* dynamic_printk_enabled, and dynamic_printk_enabled2 are bitmasks in which
* bit n is set to 1 if any modname hashes into the bucket n, 0 otherwise. They
* use independent hash functions, to reduce the chance of false positives.
*/
extern long long dynamic_debug_enabled;
extern long long dynamic_debug_enabled2;
/*
* 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:24;
/*
* 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_PRINT (1<<0) /* printk() a message using the format */
#define _DPRINTK_FLAGS_DEFAULT 0
unsigned int flags:8;
char enabled;
} __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);
#define dynamic_pr_debug(fmt, ...) do { \
__label__ do_printk; \
__label__ out; \
static struct _ddebug descriptor \
__used \
__attribute__((section("__verbose"), aligned(8))) = \
{ KBUILD_MODNAME, __func__, __FILE__, fmt, __LINE__, \
_DPRINTK_FLAGS_DEFAULT }; \
JUMP_LABEL(&descriptor.enabled, do_printk); \
goto out; \
do_printk: \
printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__); \
out: ; \
} while (0)
#define dynamic_dev_dbg(dev, fmt, ...) do { \
__label__ do_printk; \
__label__ out; \
static struct _ddebug descriptor \
__used \
__attribute__((section("__verbose"), aligned(8))) = \
{ KBUILD_MODNAME, __func__, __FILE__, fmt, __LINE__, \
_DPRINTK_FLAGS_DEFAULT }; \
JUMP_LABEL(&descriptor.enabled, do_printk); \
goto out; \
do_printk: \
dev_printk(KERN_DEBUG, dev, fmt, ##__VA_ARGS__); \
out: ; \
} while (0)
#else
static inline int ddebug_remove_module(const char *mod)
{
return 0;
}
#define dynamic_pr_debug(fmt, ...) \
do { if (0) printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__); } while (0)
#define dynamic_dev_dbg(dev, format, ...) \
do { if (0) dev_printk(KERN_DEBUG, dev, fmt, ##__VA_ARGS__); } while (0)
#endif
#endif
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