tree 81f7ba2a050d2ddb033bf690ade41052a866d7fb
parent 7fdefc10e1d730d4608cc59d386bc446f5b9ee99
author Paul E. McKenney <paul.mckenney@linaro.org> 1340297650 -0700
committer Paul E. McKenney <paulmck@linux.vnet.ibm.com> 1348411313 -0700

rcu: Prevent offline CPUs from executing RCU core code

Earlier versions of RCU invoked the RCU core from the CPU_DYING notifier
in order to note a quiescent state for the outgoing CPU.  Because the
CPU is marked "offline" during the execution of the CPU_DYING notifiers,
the RCU core had to tolerate being invoked from an offline CPU.  However,
commit b1420f1c (Make rcu_barrier() less disruptive) left only tracing
code in the CPU_DYING notifier, so the RCU core need no longer execute
on offline CPUs.  This commit therefore enforces this restriction.

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>