On Thu, Feb 2, 2023 at 8:35 PM Zqiang <qiang1.zhang@xxxxxxxxx> wrote: > > When setting nocbs_nthreads to start rcutorture test with a non-zero value, > the nocb tasks will be created and invoke rcu_nocb_cpu_offload/deoffload() > to toggle CPU's callback-offload state, but for CONFIG_RCU_NOCB_CPU=n > kernel, the rcu_nocb_cpu_offload/deoffload() is a no-op and this is also > meaningless for torture_type is non-rcu. > > This commit therefore add member can_nocbs_toggle to rcu_torture_ops > structure to avoid unnecessary nocb tasks creation. > > Signed-off-by: Zqiang <qiang1.zhang@xxxxxxxxx> Reviewed-by: Joel Fernandes (Google) <joel@xxxxxxxxxxxxxxxxx> thanks, - Joel > --- > kernel/rcu/rcutorture.c | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c > index 297da28ce92d..d01127e0e8cd 100644 > --- a/kernel/rcu/rcutorture.c > +++ b/kernel/rcu/rcutorture.c > @@ -3708,6 +3708,12 @@ rcu_torture_init(void) > pr_alert("rcu-torture: ->fqs NULL and non-zero fqs_duration, fqs disabled.\n"); > fqs_duration = 0; > } > + if (nocbs_nthreads != 0 && (cur_ops != &rcu_ops || > + !IS_ENABLED(CONFIG_RCU_NOCB_CPU))) { > + pr_alert("rcu-torture types: %s and CONFIG_RCU_NOCB_CPU=%d, nocb toggle disabled.\n", > + cur_ops->name, IS_ENABLED(CONFIG_RCU_NOCB_CPU)); > + nocbs_nthreads = 0; > + } > if (cur_ops->init) > cur_ops->init(); > > -- > 2.25.1 >