Re: [PATCH v1] kernel/events/core: check return value of task_function_call()

From: Li Zhong
Date: Mon Sep 19 2022 - 14:36:12 EST


On Mon, Sep 19, 2022 at 7:39 AM Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote:
>
> On Fri, Sep 16, 2022 at 06:47:46PM -0700, Li Zhong wrote:
> > Check the return value of task_function_call(), which could be error
> > code when the execution fails.
>
> How is terminating the cgroup task iteration a useful thing? Also coding
> style fail for not adding { }

Thanks for your reply! Skip and continue the execution is more appropriate
here. Change it in v2 patch.

>
> > Signed-off-by: Li Zhong <floridsleeves@xxxxxxxxx>
> > ---
> > kernel/events/core.c | 3 ++-
> > 1 file changed, 2 insertions(+), 1 deletion(-)
> >
> > diff --git a/kernel/events/core.c b/kernel/events/core.c
> > index 2621fd24ad26..ac0cf611b12a 100644
> > --- a/kernel/events/core.c
> > +++ b/kernel/events/core.c
> > @@ -13520,7 +13520,8 @@ static void perf_cgroup_attach(struct cgroup_taskset *tset)
> > struct cgroup_subsys_state *css;
> >
> > cgroup_taskset_for_each(task, css, tset)
> > - task_function_call(task, __perf_cgroup_move, task);
> > + if (!task_function_call(task, __perf_cgroup_move, task))
> > + return;
> > }
> >
> > struct cgroup_subsys perf_event_cgrp_subsys = {
> > --
> > 2.25.1
> >