tree f2ee193817ab4ce4ca4f789033d65a8a326d16bf
parent ae15018456c44b742d352af323e0b89eae4a6383
author Paul E. McKenney <paulmck@linux.vnet.ibm.com> 1371761440 -0700
committer Paul E. McKenney <paulmck@linux.vnet.ibm.com> 1376872809 -0700

rcu: Avoid redundant grace-period kthread wakeups

When setting up an in-the-future "advanced" grace period, the code needs
to wake up the relevant grace-period kthread, which it currently does
unconditionally.  However, this results in needless wakeups in the case
where the advanced grace period is being set up by the grace-period
kthread itself, which is a non-uncommon situation.  This commit therefore
checks to see if the running thread is the grace-period kthread, and
avoids doing the irq_work_queue()-mediated wakeup in that case.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>