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Date:   Tue, 22 Feb 2022 20:46:05 +0100
From:   Florian Westphal <fw@strlen.de>
To:     Eric Dumazet <eric.dumazet@gmail.com>
Cc:     Pablo Neira Ayuso <pablo@netfilter.org>,
        Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>,
        Florian Westphal <fw@strlen.de>,
        netfilter-devel@vger.kernel.org, netdev <netdev@vger.kernel.org>,
        Eric Dumazet <edumazet@google.com>
Subject: Re: [PATCH net] netfilter: nf_tables: prefer kfree_rcu(ptr, rcu)
 variant
Message-ID: <20220222194605.GA28705@breakpoint.cc>
References: <20220222181331.811085-1-eric.dumazet@gmail.com>
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Eric Dumazet <eric.dumazet@gmail.com> wrote:
> From: Eric Dumazet <edumazet@google.com>
> 
> While kfree_rcu(ptr) _is_ supported, it has some limitations.
> 
> Given that 99.99% of kfree_rcu() users [1] use the legacy
> two parameters variant, and @catchall objects do have an rcu head,
> simply use it.
> 
> Choice of kfree_rcu(ptr) variant was probably not intentional.

In case someone wondered, this causes expensive
sycnhronize_rcu + kfree for each removal operation.

Reviewed-by: Florian Westphal <fw@strlen.de>