On Fri, Jun 06, 2025 at 04:27:31PM -0400, Yury Norov wrote:
> From: "Yury Norov [NVIDIA]" <yury.norov@gmail.com>
>
> Defer check for local execution to the actual place where it is needed,
> and save some stack on a useless local variable.
>
> Signed-off-by: Yury Norov [NVIDIA] <yury.norov@gmail.com>
> ---
> kernel/smp.c | 10 +++-------
> 1 file changed, 3 insertions(+), 7 deletions(-)
>
> diff --git a/kernel/smp.c b/kernel/smp.c
> index 715190669e94..867f79689684 100644
> --- a/kernel/smp.c
> +++ b/kernel/smp.c
> @@ -779,7 +779,6 @@ static void smp_call_function_many_cond(const struct cpumask *mask,
> bool wait = scf_flags & SCF_WAIT;
> int nr_cpus = 0;
> bool run_remote = false;
> - bool run_local = false;
>
> lockdep_assert_preemption_disabled();
>
> @@ -801,11 +800,6 @@ static void smp_call_function_many_cond(const struct cpumask *mask,
> */
> WARN_ON_ONCE(!in_task());
>
> - /* Check if we need local execution. */
> - if ((scf_flags & SCF_RUN_LOCAL) && cpumask_test_cpu(this_cpu, mask) &&
> - (!cond_func || cond_func(this_cpu, info)))
> - run_local = true;
> -
> /* Check if we need remote execution, i.e., any CPU excluding this one. */
> if (cpumask_any_and_but(mask, cpu_online_mask, this_cpu) < nr_cpu_ids) {
> run_remote = true;
> @@ -853,7 +847,9 @@ static void smp_call_function_many_cond(const struct cpumask *mask,
> run_remote = false;
> }
>
> - if (run_local) {
> + /* Check if we need local execution. */
> + if ((scf_flags & SCF_RUN_LOCAL) & cpumask_test_cpu(this_cpu, mask) &&
> + (!cond_func || cond_func(this_cpu, info))) {
Dan Carpenter's robot pointed the bug here: it should be:
(scf_flags & SCF_RUN_LOCAL) && cpumask_test_cpu(this_cpu, mask)
I'll resend it shortly.
Thanks, Dan!
> unsigned long flags;
>
> local_irq_save(flags);
> --
> 2.43.0