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Subject: Re: Build failures in -next due to 'locking/atomic, arch/arc:
 Implement atomic_fetch_{add,sub,and,andnot,or,xor}()'
To: Peter Zijlstra <peterz@infradead.org>
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CC: Noam Camus <noamca@mellanox.com>, Guenter Roeck <linux@roeck-us.net>,
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        <linux-snps-arc@lists.infradead.org>, Ingo Molnar <mingo@kernel.org>,
        "Will Deacon" <will.deacon@arm.com>,
        Gilad Ben Yossef <giladby@mellanox.com>
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From: Vineet Gupta <Vineet.Gupta1@synopsys.com>
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Date: Fri, 17 Jun 2016 17:36:11 +0200
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On Friday 17 June 2016 05:22 PM, Peter Zijlstra wrote:
> Question; why does atomic_read() have a full memory clobber on arc?
> 
> Will thinks its because you don't use a memory constraint for *v.

So that is only for CONFIG_ARC_PLAT_EZNPS and very liekly not needed. Although NPS
has some design constraints which Noam knows of better !