tree d697f2c9dcf59d2defb6693866bf33cc45307dca
parent 0e0fc1c23e04c15e814763f2b366e92d87d8b95d
author Paul E. McKenney <paulmck@linux.vnet.ibm.com> 1258094103 -0800
committer Ingo Molnar <mingo@elte.hu> 1258103916 +0100

rcu: Accelerate callback processing on CPUs not detecting GP end

An earlier fix for a race resulted in a situation where the CPUs
other than the CPU that detected the end of the grace period would
not process their callbacks until the next grace period started.

This means that these other CPUs would unnecessarily demand that an
extra grace period be started.

This patch eliminates this extra grace period and speeds callback
processing by propagating rsp->completed to the rcu_node structures
in the case where the CPU detecting the end of the grace period
sees no reason to start a new grace period.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: mathieu.desnoyers@polymtl.ca
Cc: josh@joshtriplett.org
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
Cc: Valdis.Kletnieks@vt.edu
Cc: dhowells@redhat.com
LKML-Reference: <1258094104417-git-send-email->
Signed-off-by: Ingo Molnar <mingo@elte.hu>