rcu: Don't track sysidle state if no nohz_full= CPUs
authorPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Mon, 21 Jul 2014 18:34:33 +0000 (11:34 -0700)
committerPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Tue, 16 Sep 2014 17:08:02 +0000 (10:08 -0700)
commit663e131090dd10bac9dc0b4f5b624dd3211b20f6
tree88a47a1b26fe1af6a4c57a8e8bbee231b331c56d
parent417e8d26557c4264a484d78a7491316751afa46f
rcu: Don't track sysidle state if no nohz_full= CPUs

If there are no nohz_full= CPUs, then there is currently no reason to
track sysidle state.  This commit therefore short-circuits this state
tracking if !tick_nohz_full_enabled().

Note that these checks will need to be revisited if nohz_full= state
can ever be changed at runtime.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Tested-by: Paul Gortmaker <paul.gortmaker@windriver.com>
kernel/rcu/tree_plugin.h