From: Dmitry Vyukov <dvyukov@google.com>
Subject: Re: SLAB_TYPESAFE_BY_RCU without constructors (was Re: [PATCH v4
 13/17] khwasan: add hooks implementation)
Date: Tue, 31 Jul 2018 19:51:09 +0200
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Cc: Christoph Lameter <cl@linux.com>,
        Andrey Ryabinin <aryabinin@virtuozzo.com>,
        "Theodore Ts'o" <tytso@mit.edu>, Jan Kara <jack@suse.com>,
        linux-ext4@vger.kernel.org,
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        netdev <netdev@vger.kernel.org>,
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        Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>,
        Hideaki YOSHIFUJI <yosh
To: Eric Dumazet <edumazet@google.com>
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On Tue, Jul 31, 2018 at 7:41 PM, Eric Dumazet <edumazet@google.com> wrote:
> On Tue, Jul 31, 2018 at 10:36 AM Christopher Lameter <cl@linux.com> wrote:
>
>>
>> If there is refcounting going on then why use SLAB_TYPESAFE_BY_RCU?
>
> To allow fast reuse of objects, without going through call_rcu() and
> reducing cache efficiency.
>
> I believe this is mentioned in Documentation/RCU/rculist_nulls.txt


Is it OK to overwrite ct->status? It seems that are some read and
writes to it right after atomic_inc_not_zero.