[PATCH 03/15] bugs/core: Introduce the CONFIG_DEBUG_BUGVERBOSE_DETAILED Kconfig switch

[Ingo Molnar <mingo@kernel.org>]

Allow configurability of the inclusion of more detailed
WARN_ON() strings, to be implemented in subsequent
commits.

Since the full cost will be around 100K more memory on
an x86 defconfig, disable it by default.

Provide the WARN_CONDITION_STR() macro to allow the conditional
passing of extra strings to lower level BUG/WARN handlers.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: <linux-arch@vger.kernel.org>
---
 include/asm-generic/bug.h |  6 ++++++
 lib/Kconfig.debug         | 10 ++++++++++
 2 files changed, 16 insertions(+)

diff --git a/include/asm-generic/bug.h b/include/asm-generic/bug.h
index c8e7126bc26e..bc7a22e2bf49 100644
--- a/include/asm-generic/bug.h
+++ b/include/asm-generic/bug.h
@@ -92,6 +92,12 @@ void warn_slowpath_fmt(const char *file, const int line, unsigned taint,
 		       const char *fmt, ...);
 extern __printf(1, 2) void __warn_printk(const char *fmt, ...);
 
+#ifdef CONFIG_DEBUG_BUGVERBOSE_DETAILED
+# define WARN_CONDITION_STR(cond_str) cond_str
+#else
+# define WARN_CONDITION_STR(cond_str) ""
+#endif
+
 #ifndef __WARN_FLAGS
 #define __WARN()		__WARN_printf(TAINT_WARN, NULL)
 #define __WARN_printf(taint, arg...) do {				\
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index f9051ab610d5..59fb70b307e4 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -206,6 +206,16 @@ config DEBUG_BUGVERBOSE
 	  of the BUG call as well as the EIP and oops trace.  This aids
 	  debugging but costs about 70-100K of memory.
 
+config DEBUG_BUGVERBOSE_DETAILED
+	bool "Verbose WARN_ON_ONCE() reporting (adds 100K)" if DEBUG_BUGVERBOSE
+	help
+	  Say Y here to make WARN_ON_ONCE() output the condition string of the
+	  warning, in addition to the file name and line number.
+	  This helps debugging, but costs about 100K of memory.
+
+	  Say N if unsure.
+
+
 endmenu # "printk and dmesg options"
 
 config DEBUG_KERNEL
-- 
2.45.2