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Date: Tue, 3 Nov 2009 10:02:34 -0500
From: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
To: Josh Triplett <josh@joshtriplett.org>, Jon Bernard <jbernard@debian.org>,
       Jan Blunck <jblunck@suse.de>,
       "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
       Pierre Habouzit <madcoder@debian.org>,
       Steven Munroe <munroesj@linux.vnet.ibm.com>,
       Bert Wesarg <bert.wesarg@googlemail.com>,
       Pierre-Marc Fournier <pierre-marc.fournier@polymtl.ca>
Cc: ltt-dev@lists.casi.polymtl.ca, rp@svcs.cs.pdx.edu,
       linux-kernel@vger.kernel.org
Subject: [RELEASE] Userspace RCU 0.3.0
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Hi everyone,

I released userspace RCU 0.3.0, which includes a small API change for
the "deferred work" interface. After discussion with Paul, I decided to
drop the support for call_rcu() and only provide defer_rcu(), to make
sure I don't provide an API with the same name as the kernel RCU but
with different arguments and semantic. It will generate the following
linker error if used:

file.c:240: undefined reference to 
   `__error_call_rcu_not_implemented_please_use_defer_rcu'

Note that defer_rcu() should *not* be used in RCU read-side C.S.,
because it calls synchronize_rcu() if the queue is full. This is a major
distinction from call_rcu(). (note to self: eventually we should add
some self-check code to detect defer_rcu() nested within RCU read-side
C.S.).

I plan to eventually implement a proper call_rcu() within the userspace
RCU library. It's not, however, a short-term need for me at the moment.

Thanks,

Mathieu

-- 
Mathieu Desnoyers
OpenPGP key fingerprint: 8CD5 52C3 8E3C 4140 715F  BA06 3F25 A8FE 3BAE 9A68