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Date:   Thu, 4 May 2023 17:24:24 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Wander Lairson Costa <wander@redhat.com>
Cc:     Oleg Nesterov <oleg@redhat.com>, Ingo Molnar <mingo@redhat.com>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
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        Jiri Olsa <jolsa@kernel.org>,
        Namhyung Kim <namhyung@kernel.org>,
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        Adrian Hunter <adrian.hunter@intel.com>,
        Will Deacon <will@kernel.org>,
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        Paul McKenney <paulmck@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>
Subject: Re: [PATCH v7 2/3] sched/task: Add the put_task_struct_atomic_safe()
 function
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On Thu, May 04, 2023 at 11:55:15AM -0300, Wander Lairson Costa wrote:

> > Then I'm thinking something trivial like so:
> >
> > static inline void put_task_struct(struct task_struct *t)
> > {
> >         if (!refcount_dec_and_test(&t->usage))
> >                 return;
> >
> >         if (IS_ENABLED(CONFIG_PREEMPT_RT) && !preemptible())
> >                 call_rcu(&t->rcu, __put_task_struct_rcu);
> >
> >         __put_task_struct(t);
> > }
> >
> 
> That's what v5 [1] does. What would be the path in this case? Should I
> resend it as v8?

It's almost what v5 does. v5 also has a !in_task() thing. v5 also
violates codingstyle :-)

But yeah.. something like that.