sched: Turn lock_task_sighand() into a static inline

It appears that sparse tool understands static inline functions
for context balance checking, so let's turn the macros into an
inline func.

This makes the code a little bit more robust.

Suggested-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Cc: KOSAKI Motohiro <kosaki.motohiro@gmail.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Arve <arve@android.com>
Cc: San Mehat <san@google.com>
Cc: Colin Cross <ccross@android.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: kernel-team@android.com
Cc: linaro-kernel@lists.linaro.org
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20120209164519.GA10266@oksana.dev.rtsoft.ru
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 9 insertions, 6 deletions

diff --git a/include/linux/sched.h b/include/linux/sched.h
index 92313a3f6f77..5dba2ad52431 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -2393,12 +2393,15 @@ static inline void task_unlock(struct task_struct *p)
 extern struct sighand_struct *__lock_task_sighand(struct task_struct *tsk,
                                                         unsigned long *flags);
 
-#define lock_task_sighand(tsk, flags)                                   \
-({      struct sighand_struct *__ss;                                    \
-        __cond_lock(&(tsk)->sighand->siglock,                           \
-                    (__ss = __lock_task_sighand(tsk, flags)));          \
-        __ss;                                                           \
-})                                                                      \
+static inline struct sighand_struct *lock_task_sighand(struct task_struct *tsk,
+                                                       unsigned long *flags)
+{
+        struct sighand_struct *ret;
+
+        ret = __lock_task_sighand(tsk, flags);
+        (void)__cond_lock(&tsk->sighand->siglock, ret);
+        return ret;
+}
 
 static inline void unlock_task_sighand(struct task_struct *tsk,
                                                 unsigned long *flags)