From 5ab7ab8362fa8a4f7995d65ea05edf71530e8004 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Fri, 21 Sep 2018 18:08:09 -0700 Subject: rcutorture: Affinity forward-progress test to avoid housekeeping CPUs This commit affinities the forward-progress tests to avoid hogging a housekeeping CPU on the theory that the offloaded callbacks will be running on those housekeeping CPUs. Signed-off-by: Paul E. McKenney [ paulmck: Fix NULL-pointer issue located by kbuild test robot. ] Tested-by: Rong Chen --- kernel/rcu/tree_plugin.h | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'kernel/rcu/tree_plugin.h') diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h index 605ff3b06098..25fe26c4e9c1 100644 --- a/kernel/rcu/tree_plugin.h +++ b/kernel/rcu/tree_plugin.h @@ -2603,6 +2603,17 @@ static bool init_nocb_callback_list(struct rcu_data *rdp) return true; } +/* + * Bind the current task to the offloaded CPUs. If there are no offloaded + * CPUs, leave the task unbound. Splat if the bind attempt fails. + */ +void rcu_bind_current_to_nocb(void) +{ + if (cpumask_available(rcu_nocb_mask) && cpumask_weight(rcu_nocb_mask)) + WARN_ON(sched_setaffinity(current->pid, rcu_nocb_mask)); +} +EXPORT_SYMBOL_GPL(rcu_bind_current_to_nocb); + #else /* #ifdef CONFIG_RCU_NOCB_CPU */ static bool rcu_nocb_cpu_needs_barrier(int cpu) -- cgit v1.2.3