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Re: [RFC][PATCH 05/31] locking,arm64: Implement atomic{,64}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}()

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From Will Deacon <will.deacon@arm.com>
Newsgroups linux.kernel
Subject Re: [RFC][PATCH 05/31] locking,arm64: Implement atomic{,64}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}()
Date Fri, 22 Apr 2016 13:10:03 +0200
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On Fri, Apr 22, 2016 at 11:04:18AM +0200, Peter Zijlstra wrote:
> Implement FETCH-OP atomic primitives, these are very similar to the
> existing OP-RETURN primitives we already have, except they return the
> value of the atomic variable _before_ modification.
> 
> This is especially useful for irreversible operations -- such as
> bitops (because it becomes impossible to reconstruct the state prior
> to modification).
> 
> XXX lacking LSE bits

I'll cook a patch for this, but thanks for the series.

Will

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[RFC][PATCH 05/31] locking,arm64: Implement atomic{,64}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}() Peter Zijlstra <peterz@infradead.org> - 2016-04-22 12:00 +0200
  Re: [RFC][PATCH 05/31] locking,arm64: Implement  atomic{,64}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}() Will Deacon <will.deacon@arm.com> - 2016-04-22 13:10 +0200
  Re: [RFC][PATCH 05/31] locking,arm64: Implement  atomic{,64}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}() Will Deacon <will.deacon@arm.com> - 2016-04-22 16:30 +0200

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