Add a WARN() macro; this is WARN_ON() + printk arguments

Add a WARN() macro that acts like WARN_ON(), with the added feature that it
takes a printk like argument that is printed as part of the warning message.

[akpm@linux-foundation.org: fix printk arguments]
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Cc: Greg KH <greg@kroah.com>
Cc: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/include/asm-generic/bug.h b/include/asm-generic/bug.h
index 2632328d8646840aab41c8e401a1088e922754f2..a346e744e770098ee4550412d766d44942b0497b 100644 (file)
--- a/include/asm-generic/bug.h
+++ b/include/asm-generic/bug.h
@@ -34,9 +34,14 @@ struct bug_entry {
 #ifndef __WARN
 #ifndef __ASSEMBLY__
 extern void warn_on_slowpath(const char *file, const int line);
+extern void warn_slowpath(const char *file, const int line,
+               const char *fmt, ...) __attribute__((format(printf, 3, 4)));
 #define WANT_WARN_ON_SLOWPATH
 #endif
 #define __WARN() warn_on_slowpath(__FILE__, __LINE__)
+#define __WARN_printf(arg...) warn_slowpath(__FILE__, __LINE__, arg)
+#else
+#define __WARN_printf(arg...) __WARN()
 #endif
 
 #ifndef WARN_ON
@@ -48,6 +53,15 @@ extern void warn_on_slowpath(const char *file, const int line);
 })
 #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
+
 #else /* !CONFIG_BUG */
 #ifndef HAVE_ARCH_BUG
 #define BUG()
@@ -63,6 +77,14 @@ extern void warn_on_slowpath(const char *file, const int line);
        unlikely(__ret_warn_on);                                        \
 })
 #endif
+
+#ifndef WARN
+#define WARN(condition, format...) ({                                  \
+       int __ret_warn_on = !!(condition);                              \
+       unlikely(__ret_warn_on);                                        \
+})
+#endif
+
 #endif
 
 #define WARN_ON_ONCE(condition)        ({                              \

diff --git a/kernel/panic.c b/kernel/panic.c
index 425567f45b9f776148f1767b2f4af2d357a0c2fd..12c5a0a6c89bee42e44c65ee41eb4695ae180983 100644 (file)
--- a/kernel/panic.c
+++ b/kernel/panic.c
@@ -318,6 +318,28 @@ void warn_on_slowpath(const char *file, int line)
        add_taint(TAINT_WARN);
 }
 EXPORT_SYMBOL(warn_on_slowpath);
+
+
+void warn_slowpath(const char *file, int line, const char *fmt, ...)
+{
+       va_list args;
+       char function[KSYM_SYMBOL_LEN];
+       unsigned long caller = (unsigned long)__builtin_return_address(0);
+       sprint_symbol(function, caller);
+
+       printk(KERN_WARNING "------------[ cut here ]------------\n");
+       printk(KERN_WARNING "WARNING: at %s:%d %s()\n", file,
+               line, function);
+       va_start(args, fmt);
+       vprintk(fmt, args);
+       va_end(args);
+
+       print_modules();
+       dump_stack();
+       print_oops_end_marker();
+       add_taint(TAINT_WARN);
+}
+EXPORT_SYMBOL(warn_slowpath);
 #endif
 
 #ifdef CONFIG_CC_STACKPROTECTOR