[PATCH] btrfs-progs: Fix disable backtrace assert error

[Qu Wenruo <quwenruo@cn.fujitsu.com>]

Due to commit 00e769d04c2c83029d6c71(btrfs-progs: Correct value printed
by assertions/BUG_ON/WARN_ON), which changed the assert_trace()
parameter, the condition passed to assert/WARN_ON/BUG_ON are logical
notted for backtrace enabled and disabled case.

Such behavior makes us easier to pass value wrong, and in fact it did
cause us to pass wrong condition for ASSERT().

Instead of passing different conditions for ASSERT/WARN_ON/BUG_ON()
manually, this patch will use BUG_ON() to implement the resting
ASSERT/WARN_ON/BUG(), so we don't need to pass 3 different conditions
but only one.

And to further info the review for the fact that the condition should be
different, rename "assert_trace" to "bugon_trace", as unlike assert, we
will only trigger the bug when condition is true.

Also, move WARN_ON() out of the ifdef branch, as it's completely the
same for both branches.

Cc: Goldwyn Rodrigues <rgoldwyn@suse.de>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
---
 kerncompat.h | 19 +++++++++++--------
 1 file changed, 11 insertions(+), 8 deletions(-)

diff --git a/kerncompat.h b/kerncompat.h
index e374614..be77608 100644
--- a/kerncompat.h
+++ b/kerncompat.h
@@ -277,7 +277,7 @@ static inline long IS_ERR(const void *ptr)
 #define vfree(x) free(x)
 
 #ifndef BTRFS_DISABLE_BACKTRACE
-static inline void assert_trace(const char *assertion, const char *filename,
+static inline void bugon_trace(const char *assertion, const char *filename,
 			      const char *func, unsigned line, long val)
 {
 	if (!val)
@@ -287,17 +287,20 @@ static inline void assert_trace(const char *assertion, const char *filename,
 	exit(1);
 }
 
-#define BUG_ON(c) assert_trace(#c, __FILE__, __func__, __LINE__, (long)(c))
-#define WARN_ON(c) warning_trace(#c, __FILE__, __func__, __LINE__, (long)(c))
-#define	ASSERT(c) assert_trace(#c, __FILE__, __func__, __LINE__, (long)!(c))
-#define BUG() assert_trace(NULL, __FILE__, __func__, __LINE__, 1)
+#define BUG_ON(c) bugon_trace(#c, __FILE__, __func__, __LINE__, (long)(c))
 #else
 #define BUG_ON(c) assert(!(c))
-#define WARN_ON(c) warning_trace(#c, __FILE__, __func__, __LINE__, (long)(c))
-#define ASSERT(c) assert(!(c))
-#define BUG() assert(0)
 #endif
 
+#define WARN_ON(c) warning_trace(#c, __FILE__, __func__, __LINE__, (long)(c))
+/*
+ * TODO: ASSERT() should be depercated. In case like ASSERT(ret == 0), it
+ * won't output any useful value for ret.
+ * Should be replaced by BUG_ON(ret);
+ */
+#define	ASSERT(c) BUG_ON(!(c))
+#define BUG() BUG_ON(1)
+
 #define container_of(ptr, type, member) ({                      \
         const typeof( ((type *)0)->member ) *__mptr = (ptr);    \
 	        (type *)( (char *)__mptr - offsetof(type,member) );})
-- 
2.10.2