Re: [PATCH -v2 22/33] locking,sparc: Implement atomic{,64}_fetch_{add,sub,and,or,xor}()

[David Miller]

From: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Date: Tue, 31 May 2016 12:19:47 +0200

> 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).
> 
> Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>

Acked-by: David S. Miller <davem@xxxxxxxxxxxxx>