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Date: Tue, 26 Nov 2013 12:05:29 +0530
From: Vineet Gupta <Vineet.Gupta1@synopsys.com>
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To: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Peter Zijlstra <peterz@infradead.org>,
        "linux-arch@vger.kernel.org" <linux-arch@vger.kernel.org>,
        Gilad Ben-Yossef <gilad@benyossef.com>,
        "Noam Camus" <noamc@ezchip.com>, David Daney <david.daney@cavium.com>,
        James Hogan <james.hogan@imgtec.com>,
        thomas Gleixner <tglx@linutronix.de>,
        lkml <linux-kernel@vger.kernel.org>, Richard Kuo <rkuo@codeaurora.org>
Subject: Re: Preventing IPI sending races in arch code
References: <52932BE2.5010201@synopsys.com>	 <20131125110006.GU3866@twins.programming.kicks-ass.net>	 <529334CA.1000401@synopsys.com>	 <20131125122726.GZ10022@twins.programming.kicks-ass.net>	 <C2D7FE5348E1B147BCA15975FBA2307515715C@IN01WEMBXA.internal.synopsys.com>	 <1385409103.9218.15.camel@pasglop> <529427F1.2080409@synopsys.com> <1385442661.9218.51.camel@pasglop>
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On 11/26/2013 10:41 AM, Benjamin Herrenschmidt wrote:
>> Right, but the issue per-se is not clobbering of msg holder, but from POV of
>> > receiver, seeming coalescing of 2 set_bit writes to msg holder.
> That's fine. There's no expectation that N ipi_send_msg turn into N
> messages received... it turns into at least one.

OK, I was not aware of that relaxation in semantics.

Thx,
-Vineet