sched: Assert task state bits at build time
Since everybody is lazy and prone to forgetting things, make the
compiler help us a bit.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20091217121830.060186433@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 94858df..3754387 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -192,9 +192,13 @@
#define TASK_DEAD 64
#define TASK_WAKEKILL 128
#define TASK_WAKING 256
+#define TASK_STATE_MAX 512
#define TASK_STATE_TO_CHAR_STR "RSDTtZXxKW"
+extern char ___assert_task_state[1 - 2*!!(
+ sizeof(TASK_STATE_TO_CHAR_STR)-1 != ilog2(TASK_STATE_MAX)+1)];
+
/* Convenience macros for the sake of set_task_state */
#define TASK_KILLABLE (TASK_WAKEKILL | TASK_UNINTERRUPTIBLE)
#define TASK_STOPPED (TASK_WAKEKILL | __TASK_STOPPED)