tree f9fc70df7c25f80def12aeb231475405043eb1ed
parent 1f288094807861ec1e48c428d2c49ccf7aaf3767
author Shaohua Li <shaohua.li@intel.com> 1308265374 -0700
committer Paul E. McKenney <paulmck@linux.vnet.ibm.com> 1317270994 -0700

rcu: Avoid unnecessary self-wakeup of per-CPU kthreads

There are a number of cases where the RCU can find additional work
for the per-CPU kthread within the context of that per-CPU kthread.
In such cases, the per-CPU kthread is already running, so attempting
to wake itself up does nothing except waste CPU cycles.  This commit
therefore checks to see if it is in the per-CPU kthread context,
omitting the wakeup in this case.

Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>