Re: [boost] [atomic] review results

Subject: Re: [boost] [atomic] review results
From: Peter Dimov (pdimov_at_[hidden])
Date: 2011-11-07 12:06:33

>    Helge Bahmann's boost.atomic library is ACCEPTED.

Congratulations on the acceptance, and a few belated (sorry) comments:

- Boost.Atomic should not use the smart_ptr spinlock pool; it should contain 
its own under boost/atomic. It could be a straight copy of the shared_ptr 
one. Boost.Atomic is lower level than shared_ptr and should not have an 
upward dependency, because a future shared_ptr may (and will) use 
Boost.Atomic in its spinlock implementation.

- For the same reason, atomic_flag should be a proper fundamental component 
and not a wrapper over atomic_bool. atomic_flag is the building block for 
spinlocks; it should always be present and should always be lock-free. (And 
it should have ATOMIC_FLAG_INIT, because the spinlock pool needs it.)

- The interlocked implementation seems suboptimal - it doesn't use 
InterlockedExchange and InterlockedExchangeAdd. (The spelling of 
atomic_signal_fence under MSVC version something and above is 
_ReadWriteBarrier - see boost/smart_ptr/detail/spinlock_w32.hpp).

I apologize if these have already been discussed.