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Date: Mon, 18 Aug 2003 16:16:06 +0200
From: Andrea Arcangeli <andrea@suse.de>
To: Rusty Russell <rusty@rustcorp.com.au>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>, Greg KH <greg@kroah.com>,
       Andrew Morton <akpm@osdl.org>, dipankar@in.ibm.com,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
       paulmck@us.ibm.com
Subject: Re: [PATCH] RCU: Reduce size of rcu_head 1 of 2
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References: <1059830126.19819.8.camel@dhcp22.swansea.linux.org.uk> <20030808193441.56F452C25E@lists.samba.org>
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Hi,

On Fri, Aug 08, 2003 at 12:21:04PM +1000, Rusty Russell wrote:
> There are two patches.  Both reduce the size of the "struct rcu_head".
> One simply changes the struct rcu_head from a double linked list to a
> single linked list.  The other eliminates the "void *data" arg, and
> changes the prototype of the call_rcu() function to take a pointer to
> the struct rcu_head, rather than a user-defined data ptr.
> 
> It is the latter that I am concerned about changing mid-stable-series.

given the number of users (a dozen) I wouldn't be concerned about the
API change either. Much better to change it now that there arne't out of
the tree users yet. IMHO kernel internal API changes aren't a problem if
there are few users all in tree like in this case.

Andrea