tree f2265e705cd68ee7c8feb50edf328ffb7e74719f
parent 1eea999bf3600f3b58cc94870a0823485131c78e
author Paul E. McKenney <paulmck@linux.vnet.ibm.com> 1378425731 -0700
committer Paul E. McKenney <paulmck@linux.vnet.ibm.com> 1378426065 -0700

rcu: Throttle invoke_rcu_core() invocations due to non-lazy callbacks

If a non-lazy callback arrives on a CPU that has previously gone idle
with no non-lazy callbacks, invoke_rcu_core() forces the RCU core to
run.  However, it does not update the conditions, which could result
in several closely spaced invocations of the RCU core, which in turn
could result in an excessively high context-switch rate and resulting
high overhead.

This commit therefore updates the ->all_lazy and ->nonlazy_posted_snap
fields to prevent closely spaced invocations.

Reported-by: Tibor Billes <tbilles@gmx.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>