[Xen-devel] [PATCH v3 1/2] xen: add config option to include failing condition in BUG_ON() message

[Juergen Gross <jgross@xxxxxxxx>]

Today a triggering BUG_ON() will only print source file and line
information. Add the possibility to print the triggering condition like
ASSERT().

Do that by introducing BUG_VERBOSE() and add a Kconfig option to make
BUG_ON use BUG_VERBOSE().

Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
---
V3:
- move kconfig option out of DEBUG || expert section (Jan Beulich)
- fix ARM build (Jan Beulich)
- eliminate BUG_ON_VERBOSE() (Jan Beulich)
---
 xen/Kconfig.debug         | 8 +++++++-
 xen/include/asm-arm/bug.h | 6 ++++--
 xen/include/asm-x86/bug.h | 5 +++--
 xen/include/xen/lib.h     | 4 ++++
 4 files changed, 18 insertions(+), 5 deletions(-)

diff --git a/xen/Kconfig.debug b/xen/Kconfig.debug
index b3511e81a2..75c855e4ae 100644
--- a/xen/Kconfig.debug
+++ b/xen/Kconfig.debug
@@ -11,6 +11,13 @@ config DEBUG
 
          You probably want to say 'N' here.
 
+config DEBUG_BUGVERBOSE
+       bool "Verbose BUG_ON messages"
+       default DEBUG
+       ---help---
+         In case a BUG_ON triggers additionally print the triggering
+         condition on the console.
+
 if DEBUG || EXPERT = "y"
 
 config CRASH_DEBUG
@@ -81,7 +88,6 @@ config PERF_ARRAYS
        ---help---
          Enables software performance counter array histograms.
 
-
 config VERBOSE_DEBUG
        bool "Verbose debug messages"
        default DEBUG
diff --git a/xen/include/asm-arm/bug.h b/xen/include/asm-arm/bug.h
index 36c803357c..90b231e77a 100644
--- a/xen/include/asm-arm/bug.h
+++ b/xen/include/asm-arm/bug.h
@@ -60,11 +60,13 @@ struct bug_frame {
 
 #define WARN() BUG_FRAME(BUGFRAME_warn, __LINE__, __FILE__, 0, "")
 
-#define BUG() do {                                              \
-    BUG_FRAME(BUGFRAME_bug,  __LINE__, __FILE__, 0, "");        \
+#define BUG_VERBOSE(msg) do {                                   \
+    BUG_FRAME(BUGFRAME_bug,  __LINE__, __FILE__, 0, msg);       \
     unreachable();                                              \
 } while (0)
 
+#define BUG() BUG_VERBOSE("")
+
 #define assert_failed(msg) do {                                 \
     BUG_FRAME(BUGFRAME_assert, __LINE__, __FILE__, 1, msg);     \
     unreachable();                                              \
diff --git a/xen/include/asm-x86/bug.h b/xen/include/asm-x86/bug.h
index 9bb4a19420..46d282777f 100644
--- a/xen/include/asm-x86/bug.h
+++ b/xen/include/asm-x86/bug.h
@@ -60,10 +60,11 @@ struct bug_frame {
 
 
 #define WARN() BUG_FRAME(BUGFRAME_warn, __LINE__, __FILE__, 0, NULL)
-#define BUG() do {                                              \
-    BUG_FRAME(BUGFRAME_bug,  __LINE__, __FILE__, 0, NULL);      \
+#define BUG_VERBOSE(msg) do {                                   \
+    BUG_FRAME(BUGFRAME_bug,  __LINE__, __FILE__, 0, msg);       \
     unreachable();                                              \
 } while (0)
+#define BUG() BUG_VERBOSE(NULL)
 
 #define run_in_exception_handler(fn) BUG_FRAME(BUGFRAME_run_fn, 0, fn, 0, NULL)
 
diff --git a/xen/include/xen/lib.h b/xen/include/xen/lib.h
index 5d718bbdba..543b75952a 100644
--- a/xen/include/xen/lib.h
+++ b/xen/include/xen/lib.h
@@ -22,7 +22,11 @@
 #include <xen/string.h>
 #include <asm/bug.h>
 
+#ifdef CONFIG_DEBUG_BUGVERBOSE
+#define BUG_ON(p)  do { if (unlikely(p)) BUG_VERBOSE(#p);  } while (0)
+#else
 #define BUG_ON(p)  do { if (unlikely(p)) BUG();  } while (0)
+#endif
 #define WARN_ON(p) do { if (unlikely(p)) WARN(); } while (0)
 
 #if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6)
-- 
2.16.4


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/xen-devel