[PATCH] Extract and use wake_up_klogd()

Remove hack with printing space to wake up klogd.  Use explicit
wake_up_klogd().

See earlier discussion
http://groups.google.com/group/fa.linux.kernel/browse_frm/thread/75f496668409f58d/1a8f28983a51e1ff?lnk=st&q=wake_up_klogd+group%3Afa.linux.kernel&rnum=2#1a8f28983a51e1ffSigned-off-by: NAlexey Dobriyan <adobriyan@openvz.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

include/linux/kernel.h

@@ -176,6 +176,7 @@ static inline void console_verbose(void)
 }
 
 extern void bust_spinlocks(int yes);
+extern void wake_up_klogd(void);
 extern int oops_in_progress;		/* If set, an oops, panic(), BUG() or die() is in progress */
 extern int panic_timeout;
 extern int panic_on_oops;

kernel/printk.c

@@ -783,6 +783,12 @@ int is_console_locked(void)
 	return console_locked;
 }
 
+void wake_up_klogd(void)
+{
+	if (!oops_in_progress && waitqueue_active(&log_wait))
+		wake_up_interruptible(&log_wait);
+}
+
 /**
  * release_console_sem - unlock the console system
  *
@@ -825,8 +831,8 @@ void release_console_sem(void)
 	console_locked = 0;
 	up(&console_sem);
 	spin_unlock_irqrestore(&logbuf_lock, flags);
-	if (wake_klogd && !oops_in_progress && waitqueue_active(&log_wait))
-		wake_up_interruptible(&log_wait);
+	if (wake_klogd)
+		wake_up_klogd();
 }
 EXPORT_SYMBOL(release_console_sem);
 

lib/bust_spinlocks.c

@@ -19,19 +19,11 @@ void __attribute__((weak)) bust_spinlocks(int yes)
 	if (yes) {
 		oops_in_progress = 1;
 	} else {
-		int loglevel_save = console_loglevel;
 #ifdef CONFIG_VT
 		unblank_screen();
 #endif
 		oops_in_progress = 0;
-		/*
-		 * OK, the message is on the console.  Now we call printk()
-		 * without oops_in_progress set so that printk() will give klogd
-		 * and the blanked console a poke.  Hold onto your hats...
-		 */
-		console_loglevel = 15;		/* NMI oopser may have shut the console up */
-		printk(" ");
-		console_loglevel = loglevel_save;
+		wake_up_klogd();
 	}
 }