rcu: Remove expedited GP funnel-lock bypass
authorPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Sun, 31 Jan 2016 01:23:19 +0000 (17:23 -0800)
committerPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Thu, 31 Mar 2016 20:34:07 +0000 (13:34 -0700)
commite2fd9d35847d1936398d44c4df68dceb3d7f64e7
tree1893e200e6f5e87065b38fedfc9f74d19a4079b7
parent4f41530245c7fd4837152e264d120d05ae940eb0
rcu: Remove expedited GP funnel-lock bypass

Commit #cdacbe1f91264 ("rcu: Add fastpath bypassing funnel locking")
turns out to be a pessimization at high load because it forces a tree
full of tasks to wait for an expedited grace period that they probably
do not need.  This commit therefore removes this optimization.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Documentation/RCU/trace.txt
kernel/rcu/tree.c
kernel/rcu/tree.h
kernel/rcu/tree_trace.c