Stupid mismerge in __might_sleep meant that with the right config options
dmesg would have been swamped with false warnings. This was making BFS consume
a lot of CPU under certain conditions in combination with preempt RCU.
Thanks to Jayson R King for picking it up!

-ck

---
 include/linux/sched.h |    2 +-
 init/Kconfig          |    7 ++-----
 kernel/sched_bfs.c    |   28 +++++++++++++++++-----------
 3 files changed, 20 insertions(+), 17 deletions(-)

Index: linux-2.6.32-bfs/include/linux/sched.h
===================================================================
--- linux-2.6.32-bfs.orig/include/linux/sched.h	2009-12-30 23:15:15.621772786 +1100
+++ linux-2.6.32-bfs/include/linux/sched.h	2009-12-30 23:15:51.622771796 +1100
@@ -1585,7 +1585,7 @@ static inline void tsk_cpus_current(stru
 
 static inline void print_scheduler_version(void)
 {
-	printk(KERN_INFO"BFS CPU scheduler v0.312 by Con Kolivas.\n");
+	printk(KERN_INFO"BFS CPU scheduler v0.313 by Con Kolivas.\n");
 }
 
 static inline int iso_task(struct task_struct *p)
Index: linux-2.6.32-bfs/init/Kconfig
===================================================================
--- linux-2.6.32-bfs.orig/init/Kconfig	2009-12-30 23:15:22.491770299 +1100
+++ linux-2.6.32-bfs/init/Kconfig	2009-12-30 23:15:51.651769616 +1100
@@ -30,11 +30,8 @@ config SCHED_BFS
 	  responsiveness on the desktop and solid scalability on normal
           hardware. Not recommended for 4096 CPUs.
 
-	  Currently incompatible with the Group CPU scheduler, RCU TORTURE
-          TEST so these options are disabled. Problems have also been reported
-          with the preemptible tree based hierarchical RCU, so if you run into
-          problems with this, try the non preemptible option or classical
-          option.
+	  Currently incompatible with the Group CPU scheduler, and RCU TORTURE
+          TEST so these options are disabled.
 
           Say Y here.
 	default y
Index: linux-2.6.32-bfs/kernel/sched_bfs.c
===================================================================
--- linux-2.6.32-bfs.orig/kernel/sched_bfs.c	2009-12-30 23:15:15.645780795 +1100
+++ linux-2.6.32-bfs/kernel/sched_bfs.c	2009-12-30 23:15:51.643022345 +1100
@@ -6466,17 +6466,23 @@ void __might_sleep(char *file, int line,
 
 	if ((preempt_count_equals(preempt_offset) && !irqs_disabled()) ||
 	    system_state != SYSTEM_RUNNING || oops_in_progress)
-		if (time_before(jiffies, prev_jiffy + HZ) && prev_jiffy)
-			return;
-		prev_jiffy = jiffies;
-		printk(KERN_ERR "BUG: sleeping function called from invalid"
-				" context at %s:%d\n", file, line);
-		printk("in_atomic():%d, irqs_disabled():%d\n",
-			in_atomic(), irqs_disabled());
-		debug_show_held_locks(current);
-		if (irqs_disabled())
-			print_irqtrace_events(current);
-		dump_stack();
+		return;
+	if (time_before(jiffies, prev_jiffy + HZ) && prev_jiffy)
+		return;
+	prev_jiffy = jiffies;
+
+	printk(KERN_ERR
+		"BUG: sleeping function called from invalid context at %s:%d\n",
+			file, line);
+	printk(KERN_ERR
+		"in_atomic(): %d, irqs_disabled(): %d, pid: %d, name: %s\n",
+			in_atomic(), irqs_disabled(),
+			current->pid, current->comm);
+
+	debug_show_held_locks(current);
+	if (irqs_disabled())
+		print_irqtrace_events(current);
+	dump_stack();
 #endif
 }
 EXPORT_SYMBOL(__might_sleep);