sched/preempt: Rename PREEMPT_CHECK_OFFSET to PREEMPT_DISABLE_OFFSET

commit 90b62b51 upstream.

"CHECK" suggests it's only used as a comparison mask. But now it's used
further as a config-conditional preempt disabler offset. Lets
disambiguate this name.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1431441711-29753-4-git-send-email-fweisbec@gmail.comSigned-off-by: Ingo Molnar <mingo@kernel.org>
[ luis: backported to 3.16:
  - file rename: include/linux/{preempt.h} -> {preempt_mask.h} ]
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>

include/linux/preempt_mask.h

@@ -72,9 +72,9 @@
 #define in_nmi()	(preempt_count() & NMI_MASK)
 
 #if defined(CONFIG_PREEMPT_COUNT)
-# define PREEMPT_CHECK_OFFSET 1
+# define PREEMPT_DISABLE_OFFSET 1
 #else
-# define PREEMPT_CHECK_OFFSET 0
+# define PREEMPT_DISABLE_OFFSET 0
 #endif
 
 /*
@@ -90,7 +90,7 @@
  *
  * Work as expected.
  */
-#define SOFTIRQ_LOCK_OFFSET (SOFTIRQ_DISABLE_OFFSET + PREEMPT_CHECK_OFFSET)
+#define SOFTIRQ_LOCK_OFFSET (SOFTIRQ_DISABLE_OFFSET + PREEMPT_DISABLE_OFFSET)
 
 /*
  * Are we running in atomic context?  WARNING: this macro cannot
@@ -106,7 +106,7 @@
  * (used by the scheduler, *after* releasing the kernel lock)
  */
 #define in_atomic_preempt_off() \
-		((preempt_count() & ~PREEMPT_ACTIVE) != PREEMPT_CHECK_OFFSET)
+		((preempt_count() & ~PREEMPT_ACTIVE) != PREEMPT_DISABLE_OFFSET)
 
 #ifdef CONFIG_PREEMPT_COUNT
 # define preemptible()	(preempt_count() == 0 && !irqs_disabled())