On Sat, Aug 31, 2019 at 01:32:02PM -0700, Joe Perches wrote: > On Sat, 2019-08-31 at 17:25 +0200, Pali Rohár wrote: > > On Thursday 29 August 2019 10:50:39 Dmitry Torokhov wrote: > > > On Thu, Aug 29, 2019 at 07:50:23PM +0300, Denis Efremov wrote: > > > > "unlikely(IS_ERR_OR_NULL(x))" is excessive. IS_ERR_OR_NULL() already uses > > > > unlikely() internally. > > > > > > The keyword here is _internally_. > > > > > > https://lore.kernel.org/lkml/20190821174857.GD76194@dtor-ws/ > > > > > > So please no. > > I think it poor form not to simply restate your original > objection from 4 message levels below this link Thank you for the lesson in etiquette, but I posted reference to the very message I wanted. > > https://lists.gt.net/linux/kernel/2269724 > > Hm... I do not like this change. If I read code > > if (unlikely(IS_ERR_OR_NULL(priv->dev3))) > > then I know that it is really unlikely that condition will be truth and > so this is some case of error/exception or something that normally does > not happen too much. > > But if I read code > > if (IS_ERR_OR_NULL(priv->dev3)) > > I know nothing about chance that this condition will be truth. Explicit > unlikely in previous example give me more information. > > I alslo think this argument is dubious as it also applies > to any IS_ERR and all the unlikely uses have been removed > from those. No, if you read the reference I posted, the argument does not apply to all IS_ERR() instances. Majority of them are in probe() paths where we do not really care about likely/unlikely. Here we are dealing with IS_ERR in a [fairly] hot path. Thanks. -- Dmitry
