sched/headers: Move the PREEMPT_COUNT defines from <linux/sched.h> to <linux/preempt.h>

These defines are not really part of the scheduler's driver API, but are
related to the preempt count - so move them to <linux/preempt.h>.

Acked-by: Linus Torvalds <[e-mail]>
Cc: Mike Galbraith <[e-mail]>
Cc: Peter Zijlstra <[e-mail]>
Cc: Thomas Gleixner <[e-mail]>
Cc: [e-mail]
Signed-off-by: Ingo Molnar <[e-mail]>

include/linux/preempt.h

···
 /* We use the MSB mostly because its available */
 #define PREEMPT_NEED_RESCHED	0x80000000
 
+#define PREEMPT_DISABLED	(PREEMPT_DISABLE_OFFSET + PREEMPT_ENABLED)
+
+/*
+ * Disable preemption until the scheduler is running -- use an unconditional
+ * value so that it also works on !PREEMPT_COUNT kernels.
+ *
+ * Reset by start_kernel()->sched_init()->init_idle()->init_idle_preempt_count().
+ */
+#define INIT_PREEMPT_COUNT	PREEMPT_OFFSET
+
+/*
+ * Initial preempt_count value; reflects the preempt_count schedule invariant
+ * which states that during context switches:
+ *
+ *    preempt_count() == 2*PREEMPT_DISABLE_OFFSET
+ *
+ * Note: PREEMPT_DISABLE_OFFSET is 0 for !PREEMPT_COUNT kernels.
+ * Note: See finish_task_switch().
+ */
+#define FORK_PREEMPT_COUNT	(2*PREEMPT_DISABLE_OFFSET + PREEMPT_ENABLED)
+
 /* preempt_count() and related functions, depends on PREEMPT_NEED_RESCHED */
 #include <asm/preempt.h>
 

include/linux/sched.h

···
 		.sum_exec_runtime = ATOMIC64_INIT(0),		\
 	}
 
-#define PREEMPT_DISABLED	(PREEMPT_DISABLE_OFFSET + PREEMPT_ENABLED)
-
-/*
- * Disable preemption until the scheduler is running -- use an unconditional
- * value so that it also works on !PREEMPT_COUNT kernels.
- *
- * Reset by start_kernel()->sched_init()->init_idle()->init_idle_preempt_count().
- */
-#define INIT_PREEMPT_COUNT	PREEMPT_OFFSET
-
-/*
- * Initial preempt_count value; reflects the preempt_count schedule invariant
- * which states that during context switches:
- *
- *    preempt_count() == 2*PREEMPT_DISABLE_OFFSET
- *
- * Note: PREEMPT_DISABLE_OFFSET is 0 for !PREEMPT_COUNT kernels.
- * Note: See finish_task_switch().
- */
-#define FORK_PREEMPT_COUNT	(2*PREEMPT_DISABLE_OFFSET + PREEMPT_ENABLED)
-
 /**
  * struct thread_group_cputimer - thread group interval timer counts
  * @cputime_atomic:	atomic thread group interval timers.