On Tue, Apr 26, 2022 at 03:36:26PM +0800, Zhen Lei wrote:
> The local variable 'need_rcu_nocb_mask' is true only if CONFIG_NO_HZ_FULL
> is defined. So branch "if (need_rcu_nocb_mask)" can be moved within the
> scope of "#if defined(CONFIG_NO_HZ_FULL)". At this point, using variable
> 'need_rcu_nocb_mask' is not necessary, so delete it.
>
> No functional changes, but the code looks a little more concise.
>
> Signed-off-by: Zhen Lei <thunder.leizhen@xxxxxxxxxx>
> ---
> kernel/rcu/tree_nocb.h | 8 ++------
> 1 file changed, 2 insertions(+), 6 deletions(-)
>
> diff --git a/kernel/rcu/tree_nocb.h b/kernel/rcu/tree_nocb.h
> index 636d0546a4e932e..1e334e217f0afb7 100644
> --- a/kernel/rcu/tree_nocb.h
> +++ b/kernel/rcu/tree_nocb.h
> @@ -1165,15 +1165,10 @@ EXPORT_SYMBOL_GPL(rcu_nocb_cpu_offload);
> void __init rcu_init_nohz(void)
> {
> int cpu;
> - bool need_rcu_nocb_mask = false;
> struct rcu_data *rdp;
>
> #if defined(CONFIG_NO_HZ_FULL)
> - if (tick_nohz_full_running && !cpumask_empty(tick_nohz_full_mask))
> - need_rcu_nocb_mask = true;
> -#endif /* #if defined(CONFIG_NO_HZ_FULL) */
> -
> - if (need_rcu_nocb_mask) {
> + if (tick_nohz_full_running && !cpumask_empty(tick_nohz_full_mask)) {
Thanks! I suspect though that the introduction of
CONFIG_RCU_NOCB_CPU_DEFAULT_ALL has made this patch unecessary.
> if (!cpumask_available(rcu_nocb_mask)) {
> if (!zalloc_cpumask_var(&rcu_nocb_mask, GFP_KERNEL)) {
> pr_info("rcu_nocb_mask allocation failed, callback offloading disabled.\n");
> @@ -1182,6 +1177,7 @@ void __init rcu_init_nohz(void)
> }
> rcu_nocb_is_setup = true;
> }
> +#endif /* #if defined(CONFIG_NO_HZ_FULL) */
>
> if (!rcu_nocb_is_setup)
> return;
> --
> 2.26.0.106.g9fadedd
>
