[POWERPC] Generic BUG for powerpc

This makes powerpc use the generic BUG machinery.  The biggest reports the
function name, since it is redundant with kallsyms, and not needed in general.

There is an overall reduction of code, since module_32/64 duplicated several
functions.

Unfortunately there's no way to tell gcc that BUG won't return, so the BUG
macro includes a goto loop.  This will generate a real jmp instruction, which
is never used.

[akpm@osdl.org: build fix]
[paulus@samba.org: remove infinite loop in BUG_ON]
Signed-off-by: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Andi Kleen <ak@muc.de>
Cc: Hugh Dickens <hugh@veritas.com>
Cc: Michael Ellerman <michael@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

2 files changed, 40 insertions, 42 deletions

diff --git a/include/asm-powerpc/bug.h b/include/asm-powerpc/bug.h
index 978b2c7..7095688 100644
--- a/include/asm-powerpc/bug.h
+++ b/include/asm-powerpc/bug.h
@@ -13,36 +13,39 @@
 
 #ifndef __ASSEMBLY__
 
-struct bug_entry {
-	unsigned long	bug_addr;
-	long		line;
-	const char	*file;
-	const char	*function;
-};
-
-struct bug_entry *find_bug(unsigned long bugaddr);
-
-/*
- * If this bit is set in the line number it means that the trap
- * is for WARN_ON rather than BUG or BUG_ON.
- */
-#define BUG_WARNING_TRAP	0x1000000
-
 #ifdef CONFIG_BUG
 
+/* _EMIT_BUG_ENTRY expects args %0,%1,%2,%3 to be FILE, LINE, flags and
+   sizeof(struct bug_entry), respectively */
+#ifdef CONFIG_DEBUG_BUGVERBOSE
+#define _EMIT_BUG_ENTRY				\
+	".section __bug_table,\"a\"\n"		\
+	"2:\t" PPC_LONG "1b, %0\n"		\
+	"\t.short %1, %2\n"			\
+	".org 2b+%3\n"				\
+	".previous\n"
+#else
+#define _EMIT_BUG_ENTRY				\
+	".section __bug_table,\"a\"\n"		\
+	"2:\t" PPC_LONG "1b\n"			\
+	"\t.short %2\n"				\
+	".org 2b+%3\n"				\
+	".previous\n"
+#endif
+
 /*
  * BUG_ON() and WARN_ON() do their best to cooperate with compile-time
  * optimisations. However depending on the complexity of the condition
  * some compiler versions may not produce optimal results.
  */
 
-#define BUG() do {							 \
-	__asm__ __volatile__(						 \
-		"1:	twi 31,0,0\n"					 \
-		".section __bug_table,\"a\"\n"				 \
-		"\t"PPC_LONG"	1b,%0,%1,%2\n"				 \
-		".previous"						 \
-		: : "i" (__LINE__), "i" (__FILE__), "i" (__FUNCTION__)); \
+#define BUG() do {						\
+	__asm__ __volatile__(					\
+		"1:	twi 31,0,0\n"				\
+		_EMIT_BUG_ENTRY					\
+		: : "i" (__FILE__), "i" (__LINE__),		\
+		    "i" (0), "i"  (sizeof(struct bug_entry)));	\
+	for(;;) ;						\
 } while (0)
 
 #define BUG_ON(x) do {						\
@@ -51,23 +54,21 @@ struct bug_entry *find_bug(unsigned long bugaddr);
 			BUG();					\
 	} else {						\
 		__asm__ __volatile__(				\
-		"1:	"PPC_TLNEI"	%0,0\n"			\
-		".section __bug_table,\"a\"\n"			\
-		"\t"PPC_LONG"	1b,%1,%2,%3\n"			\
-		".previous"					\
-		: : "r" ((long)(x)), "i" (__LINE__),		\
-		    "i" (__FILE__), "i" (__FUNCTION__));	\
+		"1:	"PPC_TLNEI"	%4,0\n"			\
+		_EMIT_BUG_ENTRY					\
+		: : "i" (__FILE__), "i" (__LINE__), "i" (0),	\
+		  "i" (sizeof(struct bug_entry)),		\
+		  "r" ((long)(x)));				\
 	}							\
 } while (0)
 
 #define __WARN() do {						\
 	__asm__ __volatile__(					\
 		"1:	twi 31,0,0\n"				\
-		".section __bug_table,\"a\"\n"			\
-		"\t"PPC_LONG"	1b,%0,%1,%2\n"			\
-		".previous"					\
-		: : "i" (__LINE__ + BUG_WARNING_TRAP),		\
-		    "i" (__FILE__), "i" (__FUNCTION__));	\
+		_EMIT_BUG_ENTRY					\
+		: : "i" (__FILE__), "i" (__LINE__),		\
+		  "i" (BUGFLAG_WARNING),			\
+		  "i" (sizeof(struct bug_entry)));		\
 } while (0)
 
 #define WARN_ON(x) ({						\
@@ -77,13 +78,12 @@ struct bug_entry *find_bug(unsigned long bugaddr);
 			__WARN();				\
 	} else {						\
 		__asm__ __volatile__(				\
-		"1:	"PPC_TLNEI"	%0,0\n"			\
-		".section __bug_table,\"a\"\n"			\
-		"\t"PPC_LONG"	1b,%1,%2,%3\n"			\
-		".previous"					\
-		: : "r" (__ret_warn_on),			\
-		    "i" (__LINE__ + BUG_WARNING_TRAP),		\
-		    "i" (__FILE__), "i" (__FUNCTION__));	\
+		"1:	"PPC_TLNEI"	%4,0\n"			\
+		_EMIT_BUG_ENTRY					\
+		: : "i" (__FILE__), "i" (__LINE__),		\
+		  "i" (BUGFLAG_WARNING),			\
+		  "i" (sizeof(struct bug_entry)),		\
+		  "r" (__ret_warn_on));				\
 	}							\
 	unlikely(__ret_warn_on);				\
 })
diff --git a/include/asm-powerpc/module.h b/include/asm-powerpc/module.h
index 584fabf..e5f14b1 100644
--- a/include/asm-powerpc/module.h
+++ b/include/asm-powerpc/module.h
@@ -46,8 +46,6 @@ struct mod_arch_specific {
 	unsigned int num_bugs;
 };
 
-extern struct bug_entry *module_find_bug(unsigned long bugaddr);
-
 /*
  * Select ELF headers.
  * Make empty section for module_frob_arch_sections to expand.