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 b966d56..8ed9c48 100644 (file)
--- 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, \
        .orphan_lock = __RAW_SPIN_LOCK_UNLOCKED(&sname##_state.orphan_lock), \
        .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 bcc4865..3312ed7 100644 (file)
--- a/kernel/rcutree_trace.c
+++ b/kernel/rcutree_trace.c
@@ -46,6 +46,8 @@
 #define RCU_TREE_NONCORE
 #include "rcutree.h"
 
+#define ulong2long(a) (*(long *)(&(a)))
+
 static int r_open(struct inode *inode, struct file *file,
                                        const struct seq_operations *op)
 {
@@ -116,10 +118,10 @@ static void print_one_rcu_data(struct seq_file *m, struct rcu_data *rdp)
 {
        if (!rdp->beenonline)
                return;
-       seq_printf(m, "%3d%cc=%lu g=%lu pq=%d qp=%d",
+       seq_printf(m, "%3d%cc=%ld g=%ld pq=%d qp=%d",
                   rdp->cpu,
                   cpu_is_offline(rdp->cpu) ? '!' : ' ',
-                  rdp->completed, rdp->gpnum,
+                  ulong2long(rdp->completed), ulong2long(rdp->gpnum),
                   rdp->passed_quiesce, rdp->qs_pending);
        seq_printf(m, " dt=%d/%llx/%d df=%lu",
                   atomic_read(&rdp->dynticks->dynticks),
@@ -246,8 +248,9 @@ static void print_one_rcu_state(struct seq_file *m, struct rcu_state *rsp)
        struct rcu_node *rnp;
 
        gpnum = rsp->gpnum;
-       seq_printf(m, "%s: c=%lu g=%lu s=%d jfq=%ld j=%x ",
-                  rsp->name, rsp->completed, gpnum, rsp->fqs_state,
+       seq_printf(m, "%s: c=%ld g=%ld s=%d jfq=%ld j=%x ",
+                  rsp->name, ulong2long(rsp->completed), ulong2long(gpnum),
+                  rsp->fqs_state,
                   (long)(rsp->jiffies_force_qs - jiffies),
                   (int)(jiffies & 0xffff));
        seq_printf(m, "nfqs=%lu/nfqsng=%lu(%lu) fqlh=%lu oqlen=%ld/%ld\n",
@@ -301,16 +304,16 @@ 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",
-                  rsp->name, completed, gpnum, gpage, gpmax);
+       seq_printf(m, "%s: completed=%ld  gpnum=%ld  age=%ld  max=%ld\n",
+                  rsp->name, ulong2long(completed), ulong2long(gpnum), gpage, gpmax);
 }
 
 static int show_rcugp(struct seq_file *m, void *unused)