rcu: Separate accounting of callbacks from callback-free CPUs

Currently, callback invocations from callback-free CPUs are accounted to
the CPU that registered the callback, but using the same field that is
used for normal callbacks.  This makes it impossible to determine from
debugfs output whether callbacks are in fact being diverted.  This commit
therefore adds a separate ->n_nocbs_invoked field in the rcu_data structure
in which diverted callback invocations are counted.  RCU's debugfs tracing
still displays normal callback invocations using ci=, but displayed
diverted callbacks with nci=.

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

1 files changed, 1 insertions, 1 deletions

diff --git a/kernel/rcutree_plugin.h b/kernel/rcutree_plugin.h
index 6cdc372de34c..f6e5ec2932b4 100644
--- a/kernel/rcutree_plugin.h
+++ b/kernel/rcutree_plugin.h
@@ -2406,7 +2406,7 @@ static int rcu_nocb_kthread(void *arg)
                 trace_rcu_batch_end(rdp->rsp->name, c, !!list, 0, 0, 1);
                 ACCESS_ONCE(rdp->nocb_p_count) -= c;
                 ACCESS_ONCE(rdp->nocb_p_count_lazy) -= cl;
-                rdp->n_cbs_invoked += c;
+                rdp->n_nocbs_invoked += c;
         }
         return 0;
 }