Re: [PATCH -v2 14/33] locking,m68k: Implement atomic_fetch_{add,sub,and,or,xor}()

From: Andreas Schwab
Date: Thu Jun 16 2016 - 08:53:29 EST


Peter Zijlstra <peterz@xxxxxxxxxxxxx> writes:

> On Thu, Jun 16, 2016 at 02:43:29PM +0200, Andreas Schwab wrote:
>> Peter Zijlstra <peterz@xxxxxxxxxxxxx> writes:
>> >> > +/*
>> >> > + * Am I reading these CAS loops right in that %2 is the old value and the first
>> >> > + * iteration uses an uninitialized value?
>> >> > + *
>> >> > + * Would it not make sense to add: tmp = atomic_read(v); to avoid this?
>> >> > + */
>
>> No, there is nothing to fix here.
>
> OK, care to elucidate? Clearly I need help reading this.

grep '2.*atomic_read'

Andreas.

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Andreas Schwab, schwab@xxxxxxxxxxxxxx
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