From: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Date: Thu, 26 Apr 2018 22:30:28 +0000 (-0700)
Subject: rcu: Move rcu_gp_slow() to ->gp_seq
X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=dee4f42298bba030e84035aca5c114f9fee8fa6a;p=openwrt%2Fstaging%2Fblogic.git

rcu: Move rcu_gp_slow() to ->gp_seq

This commit moves rcu_gp_slow() to ->gp_seq.  This function only uses
the grace-period number to modulate delay, so rcu_seq_ctr(rsp->gp_seq)
gets the same effect, at least in cases where the delay is to happen
more than four times per wrap of an unsigned long.

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

diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index 467cd8e5c6ff..3c3af7e2758f 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -1879,7 +1879,8 @@ static void note_gp_changes(struct rcu_state *rsp, struct rcu_data *rdp)
 static void rcu_gp_slow(struct rcu_state *rsp, int delay)
 {
 	if (delay > 0 &&
-	    !(rsp->gpnum % (rcu_num_nodes * PER_RCU_NODE_PERIOD * delay)))
+	    !(rcu_seq_ctr(rsp->gp_seq) %
+	      (rcu_num_nodes * PER_RCU_NODE_PERIOD * delay)))
 		schedule_timeout_uninterruptible(delay);
 }