From: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Date: Fri, 28 Sep 2012 17:49:58 +0000 (-0700)
Subject: rcu: Fix tracing formatting
X-Git-Tag: next-20121024~29^2^2~6
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=62b139d3fbdc5f2a19caab2850583f50bf4faeb6;p=karo-tx-linux.git

rcu: Fix tracing formatting

The rcu_state structure's ->completed field is unsigned long, so this
commit adjusts show_one_rcugp()'s printf() format to suit.  Also add
the required ACCESS_ONCE() directives while we are in this function.

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

diff --git a/kernel/rcutree.c b/kernel/rcutree.c
index 74df86bd9204..8edc71416ca6 100644
--- a/kernel/rcutree.c
+++ b/kernel/rcutree.c
@@ -68,8 +68,8 @@ static struct lock_class_key rcu_fqs_class[RCU_NUM_LVLS];
 	.level = { &sname##_state.node[0] }, \
 	.call = cr, \
 	.fqs_state = RCU_GP_IDLE, \
-	.gpnum = -300, \
-	.completed = -300, \
+	.gpnum = 0UL - 300UL, \
+	.completed = 0UL - 300UL, \
 	.onofflock = __RAW_SPIN_LOCK_UNLOCKED(&sname##_state.onofflock), \
 	.orphan_nxttail = &sname##_state.orphan_nxtlist, \
 	.orphan_donetail = &sname##_state.orphan_donelist, \
diff --git a/kernel/rcutree_trace.c b/kernel/rcutree_trace.c
index bcc4865fea8b..209e696091bd 100644
--- a/kernel/rcutree_trace.c
+++ b/kernel/rcutree_trace.c
@@ -301,15 +301,15 @@ static void show_one_rcugp(struct seq_file *m, struct rcu_state *rsp)
 	struct rcu_node *rnp = &rsp->node[0];
 
 	raw_spin_lock_irqsave(&rnp->lock, flags);
-	completed = rsp->completed;
-	gpnum = rsp->gpnum;
-	if (rsp->completed == rsp->gpnum)
+	completed = ACCESS_ONCE(rsp->completed);
+	gpnum = ACCESS_ONCE(rsp->gpnum);
+	if (completed == gpnum)
 		gpage = 0;
 	else
 		gpage = jiffies - rsp->gp_start;
 	gpmax = rsp->gp_max;
 	raw_spin_unlock_irqrestore(&rnp->lock, flags);
-	seq_printf(m, "%s: completed=%ld  gpnum=%lu  age=%ld  max=%ld\n",
+	seq_printf(m, "%s: completed=%lu  gpnum=%lu  age=%ld  max=%ld\n",
 		   rsp->name, completed, gpnum, gpage, gpmax);
 }