From mboxrd@z Thu Jan  1 00:00:00 1970
From: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Subject: Re: [PATCH net-next 2/7] rds: hold a sock ref from rds_message to
 the rds_sock
Date: Thu, 25 Jan 2018 10:35:27 -0500
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Cc: Network Development <netdev@vger.kernel.org>,
        David Miller <davem@davemloft.net>, rds-devel@oss.oracle.com,
        santosh.shilimkar@oracle.com
To: Willem de Bruijn <willemdebruijn.kernel@gmail.com>
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On (01/25/18 15:44), Willem de Bruijn wrote:
> > This patch manages the m_rs assignment in the rds_message with
> > the necessary refcount book-keeping.
> 
> You may alos be able to do the same as tcp zerocopy and
> hold an sk reference on the notification skb.

We tether the notification skb to the rds socket after the 
refcount on the rds_message goes to zero, so we already have a 
ref from the sk to the notification skb, 

If we kept a refcount of all notification skb's (even the ones that
are not ready to be unpinned yet) on the sk, then we have additional
complexity trying to figure out which skb's are ready for notification
at any point, so not sure it would make things simpler..

--Sowmini