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Date:   Thu, 4 May 2023 17:23:07 +0200
From:   Oleg Nesterov <oleg@redhat.com>
To:     Wander Lairson Costa <wander@redhat.com>
Cc:     Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@redhat.com>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        Mark Rutland <mark.rutland@arm.com>,
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        Namhyung Kim <namhyung@kernel.org>,
        Ian Rogers <irogers@google.com>,
        Adrian Hunter <adrian.hunter@intel.com>,
        Will Deacon <will@kernel.org>,
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Subject: Re: [PATCH v7 2/3] sched/task: Add the put_task_struct_atomic_safe()
 function
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On 05/04, Wander Lairson Costa wrote:
>
> On Thu, May 4, 2023 at 11:34 AM Peter Zijlstra <peterz@infradead.org> wrote:
> >
> > 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.

Yes, but as Sebastian explained CONFIG_PROVE_RAW_LOCK_NESTING won't like it.

	https://lore.kernel.org/all/Y+zFNrCjBn53%2F+Q2@linutronix.de/

Oleg.