Re: [Bisected] qemu hangs on current git

[Peter Zijlstra <peterz@infradead.org>]

On Wed, Jan 22, 2014 at 10:37:55AM +0100, Markus Trippelsdorf wrote:
> git bisect points to:
> 
> commit 8cb75e0c4ec9786b81439761eac1d18d4a931af3
> Author: Peter Zijlstra <peterz@infradead.org>
> Date:   Wed Nov 20 12:22:37 2013 +0100
> 
>     sched/preempt: Fix up missed PREEMPT_NEED_RESCHED folding
> 

No idea why kvm would go funny on that, real hardware runs fine.

You're running a !PREEMPT kernel, right? Does the below make any
difference?

---
 include/linux/preempt.h | 5 -----
 1 file changed, 5 deletions(-)

diff --git a/include/linux/preempt.h b/include/linux/preempt.h
index 59749fc48328..de83b4eb1642 100644
--- a/include/linux/preempt.h
+++ b/include/linux/preempt.h
@@ -134,7 +134,6 @@ do { \
 #undef preempt_check_resched
 #endif
 
-#ifdef CONFIG_PREEMPT
 #define preempt_set_need_resched() \
 do { \
 	set_preempt_need_resched(); \
@@ -144,10 +143,6 @@ do { \
 	if (tif_need_resched()) \
 		set_preempt_need_resched(); \
 } while (0)
-#else
-#define preempt_set_need_resched() do { } while (0)
-#define preempt_fold_need_resched() do { } while (0)
-#endif
 
 #ifdef CONFIG_PREEMPT_NOTIFIERS