srcu: Allow a second bit in rcu_seq for SRCU state

This commit increases the number of reserved bits at the bottom of an
rcu_seq grace-period counter from one to two, as will be needed to
accommodate SRCU's three-state grace periods.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>

diff --git a/kernel/rcu/rcu.h b/kernel/rcu/rcu.h
index c62df93bfc1b316a03fe9c6772e83c1c8a9f6550..87a0ac95b55148a95c0ef4f9f4569cec258741a2 100644 (file)
--- a/kernel/rcu/rcu.h
+++ b/kernel/rcu/rcu.h
@@ -61,7 +61,7 @@
  * Grace-period counter management.
  */
 
-#define RCU_SEQ_CTR_SHIFT      1
+#define RCU_SEQ_CTR_SHIFT      2
 #define RCU_SEQ_STATE_MASK     ((1 << RCU_SEQ_CTR_SHIFT) - 1)
 
 /*