> On 01 February 2017 at 10:25 Peter Zijlstra <pet...@infradead.org> wrote: > > > On Tue, Jan 31, 2017 at 09:55:08PM +0100, Fabian Frederick wrote: > > Once again it's just about readability: > > I feel APIs should be about common use-cases, not about sporadic weird cases. > > > "add -1 unless value is zero" looks more complex in code than "dec not zero" > > but maybe it's just a matter of taste :) It it's not the case why would > > there be > > more sense about having > > atomic_inc_not_zero() globally ? > > inc_not_zero() has a very strong use-case, its for lockless refcount > increment. Incrementing a 0 reference count is bad because the object > will be freed and you'll have a use-after-free. > > Arguably, once we move reference counting over to its own type, it would > make sense to remove it from atomic, specifically to discourage that use > case.
Do you know about some commit doing such conversion or could you give me 2 distinct models so I could compare ? btw atomic_inc_not_zero() is also adviced in Documentation/RCU/rcuref.txt Regards, Fabian
