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af9379c712
Provide some basic advice about when to use BUG()/BUG_ON(): never, unless there's really no better option. This matches my understanding of the standard policy ... which seems not to be written down so far, outside of LKML messages that I haven't bookmarked. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Cc: Hans Verkuil <hverkuil@xs4all.nl> Cc: Ingo Molnar <mingo@elte.hu> Cc: Arjan van de Ven <arjan@infradead.org> Cc: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
143 lines
3.5 KiB
C
143 lines
3.5 KiB
C
#ifndef _ASM_GENERIC_BUG_H
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#define _ASM_GENERIC_BUG_H
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#include <linux/compiler.h>
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#ifdef CONFIG_BUG
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#ifdef CONFIG_GENERIC_BUG
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#ifndef __ASSEMBLY__
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struct bug_entry {
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#ifndef CONFIG_GENERIC_BUG_RELATIVE_POINTERS
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unsigned long bug_addr;
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#else
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signed int bug_addr_disp;
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#endif
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#ifdef CONFIG_DEBUG_BUGVERBOSE
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#ifndef CONFIG_GENERIC_BUG_RELATIVE_POINTERS
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const char *file;
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#else
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signed int file_disp;
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#endif
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unsigned short line;
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#endif
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unsigned short flags;
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};
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#endif /* __ASSEMBLY__ */
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#define BUGFLAG_WARNING (1<<0)
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#endif /* CONFIG_GENERIC_BUG */
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/*
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* Don't use BUG() or BUG_ON() unless there's really no way out; one
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* example might be detecting data structure corruption in the middle
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* of an operation that can't be backed out of. If the (sub)system
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* can somehow continue operating, perhaps with reduced functionality,
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* it's probably not BUG-worthy.
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*
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* If you're tempted to BUG(), think again: is completely giving up
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* really the *only* solution? There are usually better options, where
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* users don't need to reboot ASAP and can mostly shut down cleanly.
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*/
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#ifndef HAVE_ARCH_BUG
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#define BUG() do { \
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printk("BUG: failure at %s:%d/%s()!\n", __FILE__, __LINE__, __func__); \
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panic("BUG!"); \
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} while (0)
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#endif
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#ifndef HAVE_ARCH_BUG_ON
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#define BUG_ON(condition) do { if (unlikely(condition)) BUG(); } while(0)
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#endif
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/*
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* WARN(), WARN_ON(), WARN_ON_ONCE, and so on can be used to report
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* significant issues that need prompt attention if they should ever
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* appear at runtime. Use the versions with printk format strings
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* to provide better diagnostics.
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*/
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#ifndef __WARN
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#ifndef __ASSEMBLY__
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extern void warn_slowpath(const char *file, const int line,
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const char *fmt, ...) __attribute__((format(printf, 3, 4)));
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#define WANT_WARN_ON_SLOWPATH
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#endif
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#define __WARN() warn_slowpath(__FILE__, __LINE__, NULL)
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#define __WARN_printf(arg...) warn_slowpath(__FILE__, __LINE__, arg)
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#else
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#define __WARN_printf(arg...) do { printk(arg); __WARN(); } while (0)
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#endif
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#ifndef WARN_ON
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#define WARN_ON(condition) ({ \
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int __ret_warn_on = !!(condition); \
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if (unlikely(__ret_warn_on)) \
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__WARN(); \
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unlikely(__ret_warn_on); \
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})
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#endif
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#ifndef WARN
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#define WARN(condition, format...) ({ \
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int __ret_warn_on = !!(condition); \
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if (unlikely(__ret_warn_on)) \
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__WARN_printf(format); \
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unlikely(__ret_warn_on); \
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})
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#endif
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#else /* !CONFIG_BUG */
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#ifndef HAVE_ARCH_BUG
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#define BUG()
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#endif
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#ifndef HAVE_ARCH_BUG_ON
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#define BUG_ON(condition) do { if (condition) ; } while(0)
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#endif
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#ifndef HAVE_ARCH_WARN_ON
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#define WARN_ON(condition) ({ \
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int __ret_warn_on = !!(condition); \
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unlikely(__ret_warn_on); \
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})
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#endif
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#ifndef WARN
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#define WARN(condition, format...) ({ \
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int __ret_warn_on = !!(condition); \
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unlikely(__ret_warn_on); \
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})
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#endif
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#endif
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#define WARN_ON_ONCE(condition) ({ \
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static int __warned; \
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int __ret_warn_once = !!(condition); \
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\
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if (unlikely(__ret_warn_once)) \
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if (WARN_ON(!__warned)) \
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__warned = 1; \
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unlikely(__ret_warn_once); \
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})
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#define WARN_ONCE(condition, format...) ({ \
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static int __warned; \
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int __ret_warn_once = !!(condition); \
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\
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if (unlikely(__ret_warn_once)) \
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if (WARN(!__warned, format)) \
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__warned = 1; \
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unlikely(__ret_warn_once); \
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})
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#define WARN_ON_RATELIMIT(condition, state) \
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WARN_ON((condition) && __ratelimit(state))
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#ifdef CONFIG_SMP
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# define WARN_ON_SMP(x) WARN_ON(x)
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#else
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# define WARN_ON_SMP(x) do { } while (0)
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#endif
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#endif
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