]> git.karo-electronics.de Git - karo-tx-linux.git/commit
rcu: Remove _rcu_barrier() dependency on __stop_machine()
authorPaul E. McKenney <paul.mckenney@linaro.org>
Fri, 3 Aug 2012 00:43:50 +0000 (17:43 -0700)
committerPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Sun, 23 Sep 2012 14:43:55 +0000 (07:43 -0700)
commit1331e7a1bbe1f11b19c4327ba0853bee2a606543
tree596d9ed379ef7e2c5d8cf1cc0ba56ade084548ec
parenta10d206ef1a83121ab7430cb196e0376a7145b22
rcu: Remove _rcu_barrier() dependency on __stop_machine()

Currently, _rcu_barrier() relies on preempt_disable() to prevent
any CPU from going offline, which in turn depends on CPU hotplug's
use of __stop_machine().

This patch therefore makes _rcu_barrier() use get_online_cpus() to
block CPU-hotplug operations.  This has the added benefit of removing
the need for _rcu_barrier() to adopt callbacks:  Because CPU-hotplug
operations are excluded, there can be no callbacks to adopt.  This
commit simplifies the code accordingly.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
kernel/rcutree.c
kernel/rcutree.h
kernel/rcutree_trace.c