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From:   David Howells <dhowells@redhat.com>
In-Reply-To: <20231116131849.GA27763@redhat.com>
References: <20231116131849.GA27763@redhat.com> <20231027095842.GA30868@redhat.com>
To:     Oleg Nesterov <oleg@redhat.com>
Cc:     dhowells@redhat.com, Marc Dionne <marc.dionne@auristor.com>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        Al Viro <viro@zeniv.linux.org.uk>,
        Chuck Lever <chuck.lever@oracle.com>,
        linux-afs@lists.infradead.org, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] rxrpc_find_service_conn_rcu: use read_seqbegin() rather than read_seqbegin_or_lock()
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Date:   Thu, 16 Nov 2023 13:41:46 +0000
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Oleg Nesterov <oleg@redhat.com> wrote:

> So do you agree that
> 
> 	- the usage of read_seqbegin_or_lock/need_seqretry in
> 	  this code makes no sense because read_seqlock_excl()
> 	  is not possible

Not exactly.  I think it should take a lock on the second pass.

> 	- this patch doesn't change the current behaviour but
> 	  simplifies the code and makes it more clear

That is true.

David