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Date: Thu, 28 May 2015 14:17:31 -0700
From: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
To: Dan Streetman <ddstreet@ieee.org>
Cc: Josh Triplett <josh@joshtriplett.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Steven Rostedt <rostedt@goodmis.org>,
        Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
        Lai Jiangshan <laijs@cn.fujitsu.com>,
        linux-kernel <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 1/2] rcu: introduce list_last_or_null_rcu
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On Thu, May 28, 2015 at 05:14:25PM -0400, Dan Streetman wrote:
> On Thu, May 28, 2015 at 5:05 PM, Paul E. McKenney
> <paulmck@linux.vnet.ibm.com> wrote:
> > On Thu, May 28, 2015 at 04:42:20PM -0400, Dan Streetman wrote:
> >> On Thu, May 28, 2015 at 4:39 PM,  <josh@joshtriplett.org> wrote:
> >> > On Thu, May 28, 2015 at 04:35:27PM -0400, Dan Streetman wrote:
> >> >> Add list_last_or_null_rcu(), to simplify getting the last entry from a
> >> >> rcu-protected list.  The standard list_last_entry() can't be used as it
> >> >> is not rcu-protected; the list may be modified concurrently.  And the
> >> >> ->prev pointer can't be used, as only the ->next pointers are protected
> >> >> by rcu.
> >> >>
> >> >> This simply iterates forward through the entire list, to get to the last
> >> >> entry.  If the list is empty, it returns NULL.
> >> >>
> >> >> Signed-off-by: Dan Streetman <ddstreet@ieee.org>
> >> >
> >> > The list iteration functions are macros because they introduce a loop
> >> > with attached loop block.  For this, is there any reason not to make it
> >> > an inline function instead of a macro?
> >>
> >> true, there's no reason i can see not to make it inline, let me send
> >> an updated patch.
> >
> > Hmmm...  If we can now do type-generic inline functions, it might make
> > sense to convert some of the others as well.
> 
> oh, ok.  how do we do type-generic inline funcs?  return void*?

I was hoping that you would tell me.  I use macros in that case.

							Thanx, Paul