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From: Mike Frysinger <vapier.adi@gmail.com>
Date: Wed, 4 May 2011 04:33:24 -0400
Message-ID: <BANLkTimctgbto3dsnJ3d3r7NggS0KF9_Sw@mail.gmail.com>
Subject: Re: [PATCH] atomic: add *_dec_not_zero
To: David Laight <David.Laight@aculab.com>
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On Wed, May 4, 2011 at 04:05, David Laight wrote:
>> Introduce an *_dec_not_zero operation. =C2=A0Make this a special case of
>> *_add_unless because batman-adv uses atomic_dec_not_zero in different
>> places like re-broadcast queue or aggregation queue management. There
>> are other non-final patches which may also want to use this macro.
>
> Isn't there a place where a default definition of this can be
> defined? Instead of adding it separately to every architecture.

that's what asm-generic is for.  if the arch isnt using it, it's
either because the arch needs to convert to it, or they're using SMP
and asm-generic doesnt yet support that for atomic.h.

for example, the Blackfin port only needed updating for the SMP case.
in the non-SMP case, we're getting the def from asm-generic/atomic.h.
-mike