sched: Remove {set,clear}_need_resched

Preemption semantics are going to change which mandate a change.

All DRM usage sites are already broken and will not be affected (much)
by this change. DRM people are aware and will remove the last few
stragglers.

For now, leave an empty stub that generates a warning, once all users
are gone we can remove this.

Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: airlied@linux.ie
Cc: daniel.vetter@ffwll.ch
Cc: paulmck@linux.vnet.ibm.com
Link: http://lkml.kernel.org/n/tip-qfc1el2zvhxiyut4ai99ij4n@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

include/linux/thread_info.h

@@ -104,8 +104,19 @@ static inline int test_ti_thread_flag(struct thread_info *ti, int flag)
 #define test_thread_flag(flag) \
 	test_ti_thread_flag(current_thread_info(), flag)
 
-#define set_need_resched()	set_thread_flag(TIF_NEED_RESCHED)
-#define clear_need_resched()	clear_thread_flag(TIF_NEED_RESCHED)
+static inline __deprecated void set_need_resched(void)
+{
+	/*
+	 * Use of this function in deprecated.
+	 *
+	 * As of this writing there are only a few users in the DRM tree left
+	 * all of which are wrong and can be removed without causing too much
+	 * grief.
+	 *
+	 * The DRM people are aware and are working on removing the last few
+	 * instances.
+	 */
+}
 
 #if defined TIF_RESTORE_SIGMASK && !defined HAVE_SET_RESTORE_SIGMASK
 /*