]> git.proxmox.com Git - mirror_ubuntu-kernels.git/commit
rcu: Place root rcu_node structure in separate lockdep class
authorPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Wed, 7 Oct 2009 04:48:18 +0000 (21:48 -0700)
committerIngo Molnar <mingo@elte.hu>
Wed, 7 Oct 2009 06:11:21 +0000 (08:11 +0200)
commit978c0b88146a7f9b364b71b5b83c5b12e7b413d7
treeb68bedc40888192d329841a786f3b1214eab91ef
parente74f4c4564455c91a3b4075bb1721993c2a95dda
rcu: Place root rcu_node structure in separate lockdep class

Before this patch, all of the rcu_node structures were in the same lockdep
class, so that lockdep would complain when rcu_preempt_offline_tasks()
acquired the root rcu_node structure's lock while holding one of the leaf
rcu_nodes' locks.

This patch changes rcu_init_one() to use a separate
spin_lock_init() for the root rcu_node structure's lock than is
used for that of all of the rest of the rcu_node structures, which
puts the root rcu_node structure's lock in its own lockdep class.

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: akpm@linux-foundation.org
Cc: mathieu.desnoyers@polymtl.ca
Cc: josh@joshtriplett.org
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: rostedt@goodmis.org
Cc: Valdis.Kletnieks@vt.edu
Cc: dhowells@redhat.com
LKML-Reference: <12548908983277-git-send-email->
Signed-off-by: Ingo Molnar <mingo@elte.hu>
kernel/rcutree.c