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From: Honnappa Nagarahalli <Honnappa.Nagarahalli@arm.com>
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Thread-Topic: [PATCH v2 1/3] eal/arm64: add 128-bit atomic compare exchange
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Subject: Re: [dpdk-dev] [PATCH v2 1/3] eal/arm64: add 128-bit atomic compare
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>=20
> 24/06/2019 18:12, Honnappa Nagarahalli:
> > > > > +	} else {
> > > > > +		rte_panic("Invalid memory order\n");
> > > >
> > > >
> > > > rte_panic should be removed from library. In this case, I think,
> > > > invalid mo can go for strongest barrier.
> >
> > It is added here to capture programming errors.
> > Memory order can be passed during compilation or during run time.
> > 'rte_panic' supports both of these.
> > Adding code with strongest memory order will mask the programming error=
.
>=20
> An error must return a specific code from the function.
> rte_panic is really forbidden in libraries.
> We are in the process of removing all of them.
Thank you for clarifying.
In this particular use case, the API is similar to '__atomic_compare_exchan=
ge' built-in. Users would expect similar behavior. If we are differing from=
 the standard behavior, we should document it in the API definition.
=20
>=20
>=20