Message-ID: <5132B2FB.4020004@redhat.com>
Date: Sat, 02 Mar 2013 21:18:35 -0500
From: Rik van Riel <riel@redhat.com>
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To: Michel Lespinasse <walken@google.com>
CC: Davidlohr Bueso <davidlohr.bueso@hp.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        "Vinod, Chegu" <chegu_vinod@hp.com>, "Low, Jason" <jason.low2@hp.com>,
        linux-tip-commits@vger.kernel.org,
        Peter Zijlstra <a.p.zijlstra@chello.nl>,
        "H. Peter Anvin" <hpa@zytor.com>,
        Andrew Morton <akpm@linux-foundation.org>, aquini@redhat.com,
        Ingo Molnar <mingo@kernel.org>, Larry Woodman <lwoodman@redhat.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Steven Rostedt <rostedt@goodmis.org>,
        Thomas Gleixner <tglx@linutronix.de>
Subject: Re: [RFC PATCH 1/2] ipc: introduce obtaining a lockless ipc object
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On 03/01/2013 11:32 PM, Michel Lespinasse wrote:

> I think it may be nicer to take the rcu read lock at the call site
> rather than in ipc_obtain_object(), to make the rcu read lock/unlock
> sites pair up more nicely. Either that or make an inline
> ipc_release_object function that pairs up with ipc_obtain_object() and
> just does an rcu_read_unlock().

I started on a patch series to untangle the IPC locking, so
it will be a little more readable, and easier to maintain.

It is a slower approach than Davidlohr's, as in, it will take
a little longer to put a patch series together, but I hope it
will be easier to debug...

I hope to post a first iteration of the series by the middle
of next week.

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