dynamic debug: Fix build issue with older gcc

On older gcc (3.3) dynamic debug fails to compile:

include/net/inet_connection_sock.h: In function `inet_csk_reset_xmit_timer':
include/net/inet_connection_sock.h:236: error: duplicate label declaration `do_printk'
include/net/inet_connection_sock.h:219: error: this is a previous declaration
include/net/inet_connection_sock.h:236: error: duplicate label declaration `out'
include/net/inet_connection_sock.h:219: error: this is a previous declaration
include/net/inet_connection_sock.h:236: error: duplicate label `do_printk'
include/net/inet_connection_sock.h:236: error: duplicate label `out'

Fix, by reverting the usage of JUMP_LABEL() in dynamic debug for now.

Cc: <stable@kernel.org>
Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Tested-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

include/linux/dynamic_debug.h

@@ -44,34 +44,24 @@ int ddebug_add_module(struct _ddebug *tab, unsigned int n,
 extern int ddebug_remove_module(const char *mod_name);
 
 #define dynamic_pr_debug(fmt, ...) do {					\
-	__label__ do_printk;						\
-	__label__ out;							\
 	static struct _ddebug descriptor				\
 	__used								\
 	__attribute__((section("__verbose"), aligned(8))) =		\
 	{ KBUILD_MODNAME, __func__, __FILE__, fmt, __LINE__,		\
 		_DPRINTK_FLAGS_DEFAULT };				\
-	JUMP_LABEL(&descriptor.enabled, do_printk);			\
-	goto out;							\
-do_printk:								\
+	if (unlikely(descriptor.enabled))				\
 		printk(KERN_DEBUG pr_fmt(fmt),	##__VA_ARGS__);		\
-out:	;								\
 	} while (0)
 
 
 #define dynamic_dev_dbg(dev, fmt, ...) do {				\
-	__label__ do_printk;						\
-	__label__ out;							\
 	static struct _ddebug descriptor				\
 	__used								\
 	__attribute__((section("__verbose"), aligned(8))) =		\
 	{ KBUILD_MODNAME, __func__, __FILE__, fmt, __LINE__,		\
 		_DPRINTK_FLAGS_DEFAULT };				\
-	JUMP_LABEL(&descriptor.enabled, do_printk);			\
-	goto out;							\
-do_printk:								\
+	if (unlikely(descriptor.enabled))				\
 		dev_printk(KERN_DEBUG, dev, fmt, ##__VA_ARGS__);	\
-out:	;								\
 	} while (0)
 
 #else

lib/dynamic_debug.c

@@ -141,11 +141,10 @@ static void ddebug_change(const struct ddebug_query *query,
 			else if (!dp->flags)
 				dt->num_enabled++;
 			dp->flags = newflags;
-			if (newflags) {
-				jump_label_enable(&dp->enabled);
-			} else {
-				jump_label_disable(&dp->enabled);
-			}
+			if (newflags)
+				dp->enabled = 1;
+			else
+				dp->enabled = 0;
 			if (verbose)
 				printk(KERN_INFO
 					"ddebug: changed %s:%d [%s]%s %s\n",