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From:   Suren Baghdasaryan <surenb@google.com>
Date:   Mon, 7 Feb 2022 17:31:26 -0800
Message-ID: <CAJuCfpEEWFYJehwRhmMAEBx8+gf6TsV=kxuSGDVXaPwhNLt1JQ@mail.gmail.com>
Subject: Re: [PATCH v2 22/35] percpu-rwsem: enable percpu_sem destruction in
 atomic context
To:     Hillf Danton <hdanton@sina.com>
Cc:     Michel Lespinasse <michel@lespinasse.org>,
        Linux-MM <linux-mm@kvack.org>,
        LKML <linux-kernel@vger.kernel.org>
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On Mon, Feb 7, 2022 at 4:21 PM Hillf Danton <hdanton@sina.com> wrote:
>
> On Mon, 7 Feb 2022 11:31:38 -0800 Suren Baghdasaryan wrote:
> >
> > Sorry for the delay. Are you concerned about the use of spin_lock()
> > inside percpu_rwsem_async_destroy() which would become a sleeping lock
> > in case of PREEMPT_RT? If so, we can use raw_spin_lock() when locking
> > destroy_list_lock. Please confirm. Thanks!
>
> Yes please replace spin lock with the raw version which can fit in
> more scenarios.

Thanks for confirmation! I'll rework my patch and will send it to
Michel to include in the next version of his patchset.

>
> Hillf
>