path: root/kernel/rcu/tree_plugin.h
diff options
authorPaul E. McKenney <>2015-08-15 14:49:50 -0700
committerPaul E. McKenney <>2015-10-06 11:10:18 -0700
commit7f21aeef722d598ba350d1834f6e4134c7b5e8de (patch)
treef4e43a84e2a4ed78241d90c25cb339b01b90b88c /kernel/rcu/tree_plugin.h
parentee968ac61d5a3440b931375d81113e0eedfcb249 (diff)
rcu: Add online/offline info to stall warning message
This commit makes the RCU CPU stall warning message print online/offline indications immediately after a hyphen following the CPU number. A "O" indicates that the global CPU-hotplug system believes that the CPU is online, a "o" that RCU perceived the CPU to be online at the beginning of the current expedited grace period, and an "N" that RCU currently believes that it will perceive the CPU as being online at the beginning of the next expedited grace period, with "." otherwise for all three indications. So for CPU 10, you would normally see "10-OoN:" indicating that everything believes that the CPU is online. Signed-off-by: Paul E. McKenney <>
Diffstat (limited to 'kernel/rcu/tree_plugin.h')
1 files changed, 6 insertions, 2 deletions
diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
index 06116ae6dfd7..57ed9c13ae5a 100644
--- a/kernel/rcu/tree_plugin.h
+++ b/kernel/rcu/tree_plugin.h
@@ -1702,8 +1702,12 @@ static void print_cpu_stall_info(struct rcu_state *rsp, int cpu)
ticks_value = rsp->gpnum - rdp->gpnum;
print_cpu_stall_fast_no_hz(fast_no_hz, cpu);
- pr_err("\t%d: (%lu %s) idle=%03x/%llx/%d softirq=%u/%u fqs=%ld %s\n",
- cpu, ticks_value, ticks_title,
+ pr_err("\t%d-%c%c%c: (%lu %s) idle=%03x/%llx/%d softirq=%u/%u fqs=%ld %s\n",
+ cpu,
+ "O."[!!cpu_online(cpu)],
+ "o."[!!(rdp->grpmask & rdp->mynode->qsmaskinit)],
+ "N."[!!(rdp->grpmask & rdp->mynode->qsmaskinitnext)],
+ ticks_value, ticks_title,
atomic_read(&rdtp->dynticks) & 0xfff,
rdtp->dynticks_nesting, rdtp->dynticks_nmi_nesting,
rdp->softirq_snap, kstat_softirqs_cpu(RCU_SOFTIRQ, cpu),