diff options
Diffstat (limited to 'include/linux/preempt.h')
| -rw-r--r-- | include/linux/preempt.h | 22 |
1 files changed, 14 insertions, 8 deletions
diff --git a/include/linux/preempt.h b/include/linux/preempt.h index 5a710b9c578e..87a03c746f17 100644 --- a/include/linux/preempt.h +++ b/include/linux/preempt.h @@ -93,14 +93,20 @@ do { \ #else /* !CONFIG_PREEMPT_COUNT */ -#define preempt_disable() do { } while (0) -#define sched_preempt_enable_no_resched() do { } while (0) -#define preempt_enable_no_resched() do { } while (0) -#define preempt_enable() do { } while (0) - -#define preempt_disable_notrace() do { } while (0) -#define preempt_enable_no_resched_notrace() do { } while (0) -#define preempt_enable_notrace() do { } while (0) +/* + * Even if we don't have any preemption, we need preempt disable/enable + * to be barriers, so that we don't have things like get_user/put_user + * that can cause faults and scheduling migrate into our preempt-protected + * region. + */ +#define preempt_disable() barrier() +#define sched_preempt_enable_no_resched() barrier() +#define preempt_enable_no_resched() barrier() +#define preempt_enable() barrier() + +#define preempt_disable_notrace() barrier() +#define preempt_enable_no_resched_notrace() barrier() +#define preempt_enable_notrace() barrier() #endif /* CONFIG_PREEMPT_COUNT */ |