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To: karim@opersys.com
Cc: Ingo Molnar <mingo@elte.hu>, linux-kernel@vger.kernel.org,
       Thomas Zanussi <trz@us.ibm.com>, Robert Wisniewski <bob@watson.ibm.com>,
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From: Roland Dreier <roland@topspin.com>
Date: Thu, 14 Oct 2004 17:31:19 -0700
In-Reply-To: <416F14B4.8070002@opersys.com> (Karim Yaghmour's message of
 "Thu, 14 Oct 2004 20:07:16 -0400")
Message-ID: <52u0swddpk.fsf@topspin.com>
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Subject: Re: [patch] Real-Time Preemption, -VP-2.6.9-rc4-mm1-U0
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    Karim> cmpxchg (basically: try reserve; if fail retry; else
    Karim> write), with per-cpu buffers.

Not sure if I really understand the context where Ingo would use this,
but this lockless scheme doesn't seem to be safe for realtime; the
retry can potentially happen an arbitrary number of times.

 - Roland
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