rcu: Hold off RCU_FAST_NO_HZ after timer posted
rcu: Hold off RCU_FAST_NO_HZ after timer posted

This commit handles workloads that transition quickly between idle and
non-idle, and where the CPU's callbacks cannot be invoked, but where
RCU does not have anything immediate for the CPU to do.  Without this
patch, the RCU_FAST_NO_HZ code can be invoked repeatedly on each entry
to idle.  The commit sets the per-CPU rcu_dyntick_holdoff variable to
hold off further attempts for a tick.

Reported-by: "Abou Gazala, Neven M" <cebfb03d2892481bb63bdbf93391f370835046dd@intel.com>
Signed-off-by: Paul E. McKenney <95dea50491c620faede961f7e6190a98a6df4edf@linaro.org>
Signed-off-by: Paul E. McKenney <1e0ce936bb9b355d257bf5790d2513c3f28be22b@linux.vnet.ibm.com>

KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs