nohz: Ensure full dynticks CPUs are RCU nocbs
authorFrederic Weisbecker <fweisbec@gmail.com>
Tue, 26 Mar 2013 22:47:24 +0000 (23:47 +0100)
committerFrederic Weisbecker <fweisbec@gmail.com>
Fri, 19 Apr 2013 11:54:04 +0000 (13:54 +0200)
commitd1e43fa5f8bb25f83a86a29f11fcfb57ed4d7566
tree9eff00255c1061248b6aef2c8341ea527610150c
parent0453b435df0d69dd0d8c42eb9b3015aaf0d8a032
nohz: Ensure full dynticks CPUs are RCU nocbs

We need full dynticks CPU to also be RCU nocb so
that we don't have to keep the tick to handle RCU
callbacks.

Make sure the range passed to nohz_full= boot
parameter is a subset of rcu_nocbs=

The CPUs that fail to meet this requirement will be
excluded from the nohz_full range. This is checked
early in boot time, before any CPU has the opportunity
to stop its tick.

Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Geoff Levand <geoff@infradead.org>
Cc: Gilad Ben Yossef <gilad@benyossef.com>
Cc: Hakan Akkan <hakanakkan@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Kevin Hilman <khilman@linaro.org>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Documentation/kernel-parameters.txt
include/linux/rcupdate.h
include/linux/tick.h
init/main.c
kernel/rcutree.c
kernel/rcutree.h
kernel/rcutree_plugin.h
kernel/time/tick-sched.c