---

yaml
---
r: 223807
b: refs/heads/master
c: 121dfc4
h: refs/heads/master
i:
  223805: 3fa5a8c
  223803: ff5a9e3
  223799: 30bd036
  223791: 8aacfdc
  223775: b4bbc42
  223743: 63afd0d
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 5ff8e6f0535fe730e921ca347bc38dcb9e01791a
+refs/heads/master: 121dfc4b3eba9e2f3c42d35205a3510cc65b9931

trunk/kernel/rcutree.c

@@ -617,9 +617,17 @@ static void __init check_cpu_stall_init(void)
 static void __note_new_gpnum(struct rcu_state *rsp, struct rcu_node *rnp, struct rcu_data *rdp)
 {
 	if (rdp->gpnum != rnp->gpnum) {
-		rdp->qs_pending = 1;
-		rdp->passed_quiesc = 0;
+		/*
+		 * If the current grace period is waiting for this CPU,
+		 * set up to detect a quiescent state, otherwise don't
+		 * go looking for one.
+		 */
 		rdp->gpnum = rnp->gpnum;
+		if (rnp->qsmask & rdp->grpmask) {
+			rdp->qs_pending = 1;
+			rdp->passed_quiesc = 0;
+		} else
+			rdp->qs_pending = 0;
 	}
 }
 
@@ -681,19 +689,20 @@ __rcu_process_gp_end(struct rcu_state *rsp, struct rcu_node *rnp, struct rcu_dat
 
 		/*
 		 * If we were in an extended quiescent state, we may have
-		 * missed some grace periods that others CPUs took care on
+		 * missed some grace periods that others CPUs handled on
 		 * our behalf. Catch up with this state to avoid noting
-		 * spurious new grace periods.
+		 * spurious new grace periods.  If another grace period
+		 * has started, then rnp->gpnum will have advanced, so
+		 * we will detect this later on.
 		 */
-		if (rdp->completed > rdp->gpnum)
+		if (ULONG_CMP_LT(rdp->gpnum, rdp->completed))
 			rdp->gpnum = rdp->completed;
 
 		/*
-		 * If another CPU handled our extended quiescent states and
-		 * we have no more grace period to complete yet, then stop
-		 * chasing quiescent states.
+		 * If RCU does not need a quiescent state from this CPU,
+		 * then make sure that this CPU doesn't go looking for one.
 		 */
-		if (rdp->completed == rnp->gpnum)
+		if ((rnp->qsmask & rdp->grpmask) == 0)
 			rdp->qs_pending = 0;
 	}
 }