Re: [PATCH v2 05/11] sched,livepatch: Use wake_up_if_idle()

From: Miroslav Benes
Date: Wed Oct 06 2021 - 05:16:30 EST


On Wed, 29 Sep 2021, Peter Zijlstra wrote:

> Make sure to prod idle CPUs so they call klp_update_patch_state().
>
> Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
> ---
> kernel/livepatch/transition.c | 5 ++++-
> 1 file changed, 4 insertions(+), 1 deletion(-)
>
> --- a/kernel/livepatch/transition.c
> +++ b/kernel/livepatch/transition.c
> @@ -413,8 +413,11 @@ void klp_try_complete_transition(void)
> for_each_possible_cpu(cpu) {
> task = idle_task(cpu);
> if (cpu_online(cpu)) {
> - if (!klp_try_switch_task(task))
> + if (!klp_try_switch_task(task)) {
> complete = false;
> + /* Make idle task go through the main loop. */
> + wake_up_if_idle(cpu);
> + }

Right, it should be enough.

Acked-by: Miroslav Benes <mbenes@xxxxxxx>

It would be nice to get Vasily's Tested-by tag on this one.

M