Re: [PATCHv2 05/16] atomics: prepare for atomic64_fetch_add_unless()
From: Michael Ellerman
Date: Tue Jun 05 2018 - 06:54:17 EST
Mark Rutland <mark.rutland@xxxxxxx> writes:
> On Tue, Jun 05, 2018 at 11:26:37AM +0200, Peter Zijlstra wrote:
>> On Tue, May 29, 2018 at 04:43:35PM +0100, Mark Rutland wrote:
>> > /**
>> > + * atomic64_add_unless - add unless the number is already a given value
>> > + * @v: pointer of type atomic_t
>> > + * @a: the amount to add to v...
>> > + * @u: ...unless v is equal to u.
>> > + *
>> > + * Atomically adds @a to @v, so long as @v was not already @u.
>> > + * Returns non-zero if @v was not @u, and zero otherwise.
>> I always get confused by that wording; would something like: "Returns
>> true if the addition was done" not be more clear?
> Sounds clearer to me; I just stole the wording from the existing
> I guess you'll want similar for the conditional inc/dec ops, e.g.
> * atomic_inc_not_zero - increment unless the number is zero
> * @v: pointer of type atomic_t
> * Atomically increments @v by 1, so long as @v is non-zero.
> * Returns non-zero if @v was non-zero, and zero otherwise.
If we're bike-shedding .. :)
I think "so long as" is overly wordy and not helpful. It'd be clearer
* Atomically increments @v by 1, if @v is non-zero.