[PATCH v3 tip/core/rcu 31/40] srcu: Allow a second bit in rcu_seq for SRCU state

From: Paul E. McKenney
Date: Wed Apr 19 2017 - 12:59:35 EST


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@xxxxxxxxxxxxxxxxxx>
---
kernel/rcu/rcu.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/rcu/rcu.h b/kernel/rcu/rcu.h
index c62df93bfc1b..87a0ac95b551 100644
--- 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)

/*
--
2.5.2