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authorDaniel Vetter <daniel.vetter@ffwll.ch>2013-03-19 04:47:30 -0400
committerDaniel Vetter <daniel.vetter@ffwll.ch>2013-03-19 04:47:30 -0400
commit0d4a42f6bd298e826620585e766a154ab460617a (patch)
tree406d8f7778691d858dbe3e48e4bbb10e99c0a58a /include/linux/context_tracking.h
parentd62b4892f3d9f7dd2002e5309be10719d6805b0f (diff)
parenta937536b868b8369b98967929045f1df54234323 (diff)
Merge tag 'v3.9-rc3' into drm-intel-next-queued
Backmerge so that I can merge Imre Deak's coalesced sg entries fixes, which depend upon the new for_each_sg_page introduce in commit a321e91b6d73ed011ffceed384c40d2785cf723b Author: Imre Deak <imre.deak@intel.com> Date: Wed Feb 27 17:02:56 2013 -0800 lib/scatterlist: add simple page iterator The merge itself is just two trivial conflicts: Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Diffstat (limited to 'include/linux/context_tracking.h')
-rw-r--r--include/linux/context_tracking.h28
1 files changed, 28 insertions, 0 deletions
diff --git a/include/linux/context_tracking.h b/include/linux/context_tracking.h
index e24339ccb7f0..b28d161c1091 100644
--- a/include/linux/context_tracking.h
+++ b/include/linux/context_tracking.h
@@ -3,12 +3,40 @@
3 3
4#ifdef CONFIG_CONTEXT_TRACKING 4#ifdef CONFIG_CONTEXT_TRACKING
5#include <linux/sched.h> 5#include <linux/sched.h>
6#include <linux/percpu.h>
7
8struct context_tracking {
9 /*
10 * When active is false, probes are unset in order
11 * to minimize overhead: TIF flags are cleared
12 * and calls to user_enter/exit are ignored. This
13 * may be further optimized using static keys.
14 */
15 bool active;
16 enum {
17 IN_KERNEL = 0,
18 IN_USER,
19 } state;
20};
21
22DECLARE_PER_CPU(struct context_tracking, context_tracking);
23
24static inline bool context_tracking_in_user(void)
25{
26 return __this_cpu_read(context_tracking.state) == IN_USER;
27}
28
29static inline bool context_tracking_active(void)
30{
31 return __this_cpu_read(context_tracking.active);
32}
6 33
7extern void user_enter(void); 34extern void user_enter(void);
8extern void user_exit(void); 35extern void user_exit(void);
9extern void context_tracking_task_switch(struct task_struct *prev, 36extern void context_tracking_task_switch(struct task_struct *prev,
10 struct task_struct *next); 37 struct task_struct *next);
11#else 38#else
39static inline bool context_tracking_in_user(void) { return false; }
12static inline void user_enter(void) { } 40static inline void user_enter(void) { }
13static inline void user_exit(void) { } 41static inline void user_exit(void) { }
14static inline void context_tracking_task_switch(struct task_struct *prev, 42static inline void context_tracking_task_switch(struct task_struct *prev,