root/include/asm-generic/bug.h

INCLUDED FROM

DEFINITIONS

1. __printf

#ifndef _ASM_GENERIC_BUG_H
#define _ASM_GENERIC_BUG_H

#include <linux/compiler.h>

#ifdef CONFIG_GENERIC_BUG
#define BUGFLAG_WARNING         (1 << 0)
#define BUGFLAG_TAINT(taint)    (BUGFLAG_WARNING | ((taint) << 8))
#define BUG_GET_TAINT(bug)      ((bug)->flags >> 8)
#endif

#ifndef __ASSEMBLY__
#include <linux/kernel.h>

#ifdef CONFIG_BUG

#ifdef CONFIG_GENERIC_BUG
struct bug_entry {
#ifndef CONFIG_GENERIC_BUG_RELATIVE_POINTERS
        unsigned long   bug_addr;
#else
        signed int      bug_addr_disp;
#endif
#ifdef CONFIG_DEBUG_BUGVERBOSE
#ifndef CONFIG_GENERIC_BUG_RELATIVE_POINTERS
        const char      *file;
#else
        signed int      file_disp;
#endif
        unsigned short  line;
#endif
        unsigned short  flags;
};
#endif  /* CONFIG_GENERIC_BUG */

/*
 * Don't use BUG() or BUG_ON() unless there's really no way out; one
 * example might be detecting data structure corruption in the middle
 * of an operation that can't be backed out of.  If the (sub)system
 * can somehow continue operating, perhaps with reduced functionality,
 * it's probably not BUG-worthy.
 *
 * If you're tempted to BUG(), think again:  is completely giving up
 * really the *only* solution?  There are usually better options, where
 * users don't need to reboot ASAP and can mostly shut down cleanly.
 */
#ifndef HAVE_ARCH_BUG
#define BUG() do { \
        printk("BUG: failure at %s:%d/%s()!\n", __FILE__, __LINE__, __func__); \
        panic("BUG!"); \
} while (0)
#endif

#ifndef HAVE_ARCH_BUG_ON
#define BUG_ON(condition) do { if (unlikely(condition)) BUG(); } while (0)
#endif

/*
 * WARN(), WARN_ON(), WARN_ON_ONCE, and so on can be used to report
 * significant issues that need prompt attention if they should ever
 * appear at runtime.  Use the versions with printk format strings
 * to provide better diagnostics.
 */
#ifndef __WARN_TAINT
extern __printf(3, 4)
void warn_slowpath_fmt(const char *file, const int line,
                       const char *fmt, ...);
extern __printf(4, 5)
void warn_slowpath_fmt_taint(const char *file, const int line, unsigned taint,
                             const char *fmt, ...);
extern void warn_slowpath_null(const char *file, const int line);
#define WANT_WARN_ON_SLOWPATH
#define __WARN()                warn_slowpath_null(__FILE__, __LINE__)
#define __WARN_printf(arg...)   warn_slowpath_fmt(__FILE__, __LINE__, arg)
#define __WARN_printf_taint(taint, arg...)                              \
        warn_slowpath_fmt_taint(__FILE__, __LINE__, taint, arg)
#else
#define __WARN()                __WARN_TAINT(TAINT_WARN)
#define __WARN_printf(arg...)   do { printk(arg); __WARN(); } while (0)
#define __WARN_printf_taint(taint, arg...)                              \
        do { printk(arg); __WARN_TAINT(taint); } while (0)
#endif

#ifndef WARN_ON
#define WARN_ON(condition) ({                                           \
        int __ret_warn_on = !!(condition);                              \
        if (unlikely(__ret_warn_on))                                    \
                __WARN();                                               \
        unlikely(__ret_warn_on);                                        \
})
#endif

#ifndef WARN
#define WARN(condition, format...) ({                                           \
        int __ret_warn_on = !!(condition);                              \
        if (unlikely(__ret_warn_on))                                    \
                __WARN_printf(format);                                  \
        unlikely(__ret_warn_on);                                        \
})
#endif

#define WARN_TAINT(condition, taint, format...) ({                      \
        int __ret_warn_on = !!(condition);                              \
        if (unlikely(__ret_warn_on))                                    \
                __WARN_printf_taint(taint, format);                     \
        unlikely(__ret_warn_on);                                        \
})

#define WARN_ON_ONCE(condition) ({                              \
        static bool __section(.data.unlikely) __warned;         \
        int __ret_warn_once = !!(condition);                    \
                                                                \
        if (unlikely(__ret_warn_once))                          \
                if (WARN_ON(!__warned))                         \
                        __warned = true;                        \
        unlikely(__ret_warn_once);                              \
})

#define WARN_ONCE(condition, format...) ({                      \
        static bool __section(.data.unlikely) __warned;         \
        int __ret_warn_once = !!(condition);                    \
                                                                \
        if (unlikely(__ret_warn_once))                          \
                if (WARN(!__warned, format))                    \
                        __warned = true;                        \
        unlikely(__ret_warn_once);                              \
})

#define WARN_TAINT_ONCE(condition, taint, format...)    ({      \
        static bool __section(.data.unlikely) __warned;         \
        int __ret_warn_once = !!(condition);                    \
                                                                \
        if (unlikely(__ret_warn_once))                          \
                if (WARN_TAINT(!__warned, taint, format))       \
                        __warned = true;                        \
        unlikely(__ret_warn_once);                              \
})

#else /* !CONFIG_BUG */
#ifndef HAVE_ARCH_BUG
#define BUG() do {} while (1)
#endif

#ifndef HAVE_ARCH_BUG_ON
#define BUG_ON(condition) do { if (condition) ; } while (0)
#endif

#ifndef HAVE_ARCH_WARN_ON
#define WARN_ON(condition) ({                                           \
        int __ret_warn_on = !!(condition);                              \
        unlikely(__ret_warn_on);                                        \
})
#endif

#ifndef WARN
#define WARN(condition, format...) ({                                   \
        int __ret_warn_on = !!(condition);                              \
        no_printk(format);                                              \
        unlikely(__ret_warn_on);                                        \
})
#endif

#define WARN_ON_ONCE(condition) WARN_ON(condition)
#define WARN_ONCE(condition, format...) WARN(condition, format)
#define WARN_TAINT(condition, taint, format...) WARN(condition, format)
#define WARN_TAINT_ONCE(condition, taint, format...) WARN(condition, format)

#endif

/*
 * WARN_ON_SMP() is for cases that the warning is either
 * meaningless for !SMP or may even cause failures.
 * This is usually used for cases that we have
 * WARN_ON(!spin_is_locked(&lock)) checks, as spin_is_locked()
 * returns 0 for uniprocessor settings.
 * It can also be used with values that are only defined
 * on SMP:
 *
 * struct foo {
 *  [...]
 * #ifdef CONFIG_SMP
 *      int bar;
 * #endif
 * };
 *
 * void func(struct foo *zoot)
 * {
 *      WARN_ON_SMP(!zoot->bar);
 *
 * For CONFIG_SMP, WARN_ON_SMP() should act the same as WARN_ON(),
 * and should be a nop and return false for uniprocessor.
 *
 * if (WARN_ON_SMP(x)) returns true only when CONFIG_SMP is set
 * and x is true.
 */
#ifdef CONFIG_SMP
# define WARN_ON_SMP(x)                 WARN_ON(x)
#else
/*
 * Use of ({0;}) because WARN_ON_SMP(x) may be used either as
 * a stand alone line statement or as a condition in an if ()
 * statement.
 * A simple "0" would cause gcc to give a "statement has no effect"
 * warning.
 */
# define WARN_ON_SMP(x)                 ({0;})
#endif

#endif /* __ASSEMBLY__ */

#endif