rcu: Move RCU grace-period initialization into a kthread
authorPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Tue, 19 Jun 2012 01:36:08 +0000 (18:36 -0700)
committerPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Sun, 23 Sep 2012 14:41:52 +0000 (07:41 -0700)
commitb3dbec76e5334fbb063987dea14e7b255602d7e4
tree5b75e737856baf09b2303bebf7d9893b8279c84e
parenta10d206ef1a83121ab7430cb196e0376a7145b22
rcu: Move RCU grace-period initialization into a kthread

As the first step towards allowing grace-period initialization to be
preemptible, this commit moves the RCU grace-period initialization
into its own kthread.  This is needed to keep large-system scheduling
latency at reasonable levels.

Also change raw_spin_lock_irqsave() to raw_spin_lock_irq() as suggested
by Peter Zijlstra in review comments.

Reported-by: Mike Galbraith <mgalbraith@suse.de>
Reported-by: Dimitri Sivanich <sivanich@sgi.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
kernel/rcutree.c
kernel/rcutree.h