On Mon, Nov 15, 2021 at 01:15:46PM +0800, Zqiang wrote: > If the nohz_full is enabled, when the boost task be created, > the cpus_allowed_ptr be set housekeeping_cpumask(HK_FLAG_KTHREAD), > however when the rcu_boost_kthread_setaffinity() be called, the > original affinity will be changed, the isolated cpus should be > considered again. > > Signed-off-by: Zqiang <qiang.zhang1211@xxxxxxxxx> I have queued this for testing and further review, thank you! I am particularly interested in Frederic's thoughts on how this might interact with any future ability to change the set of nohz_full CPUs at runtime. Thanx, Paul > --- > kernel/rcu/tree_plugin.h | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h > index 5199559fbbf0..87e7ebbdb12e 100644 > --- a/kernel/rcu/tree_plugin.h > +++ b/kernel/rcu/tree_plugin.h > @@ -1204,8 +1204,9 @@ static void rcu_boost_kthread_setaffinity(struct rcu_node *rnp, int outgoingcpu) > if ((mask & leaf_node_cpu_bit(rnp, cpu)) && > cpu != outgoingcpu) > cpumask_set_cpu(cpu, cm); > + cpumask_and(cm, cm, housekeeping_cpumask(HK_FLAG_RCU)); > if (cpumask_weight(cm) == 0) > - cpumask_setall(cm); > + cpumask_copy(cm, housekeeping_cpumask(HK_FLAG_RCU)); > set_cpus_allowed_ptr(t, cm); > free_cpumask_var(cm); > } > -- > 2.17.1 >
