timers: Reduce the CPU index space to 256k

We want to store the array index in the flags space. 256k CPUs should be
enough for a while.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Chris Mason <clm@fb.com>
Cc: George Spelvin <linux@sciencehorizons.net>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160704094342.030144293@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>

include/linux/timer.h

@@ -58,12 +58,12 @@ struct timer_list {
  * workqueue locking issues. It's not meant for executing random crap
  * with interrupts disabled. Abuse is monitored!
  */
-#define TIMER_CPUMASK		0x0007FFFF
-#define TIMER_MIGRATING		0x00080000
+#define TIMER_CPUMASK		0x0003FFFF
+#define TIMER_MIGRATING		0x00040000
 #define TIMER_BASEMASK		(TIMER_CPUMASK | TIMER_MIGRATING)
-#define TIMER_DEFERRABLE	0x00100000
-#define TIMER_PINNED		0x00200000
-#define TIMER_IRQSAFE		0x00400000
+#define TIMER_DEFERRABLE	0x00080000
+#define TIMER_PINNED		0x00100000
+#define TIMER_IRQSAFE		0x00200000
 
 #define __TIMER_INITIALIZER(_function, _expires, _data, _flags) { \
 		.entry = { .next = TIMER_ENTRY_STATIC },	\