linux/include/asm-generic/bug.h
Paul Mundt 09682c1dd3 bug.h: Fix up CONFIG_BUG=n implicit function declarations.
Commit 2603efa31a ("bug.h: Fix up powerpc build regression") corrected
the powerpc build case and extended the __ASSEMBLY__ guards, but it also
got caught in pre-processor hell accidentally matching the else case of
CONFIG_BUG resulting in the BUG disabled case tripping up on
-Werror=implicit-function-declaration.

It's not possible to __ASSEMBLY__ guard the entire file as architecture
code needs to get at the BUGFLAG_WARNING definition in the GENERIC_BUG
case, but the rest of the CONFIG_BUG=y/n case needs to be guarded.

Rather than littering endless __ASSEMBLY__ checks in each of the if/else
cases we just move the BUGFLAG definitions up under their own
GENERIC_BUG test and then shove everything else under one big
__ASSEMBLY__ guard.

Build tested on all of x86 CONFIG_BUG=y, CONFIG_BUG=n, powerpc (due to
it's dependence on BUGFLAG definitions in assembly code), and sh (due to
not bringing in linux/kernel.h to satisfy the taint flag definitions used
by the generic bug code).

Hopefully that's the end of the corner cases and I can abstain from ever
having to touch this infernal header ever again.

Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Tested-by: Fengguang Wu <wfg@linux.intel.com>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-06-25 10:32:49 -07:00

208 lines
5.5 KiB
C

#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); \
})
#else /* !CONFIG_BUG */
#ifndef HAVE_ARCH_BUG
#define BUG() do {} while(0)
#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); \
unlikely(__ret_warn_on); \
})
#endif
#define WARN_TAINT(condition, taint, format...) WARN_ON(condition)
#endif
#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); \
})
/*
* 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