Am Tuesday 01 December 2009 15:30:12 schrieb Peter Dimov:
I will add _consume to boost/memory_order.hpp.
thanks, memory_order.hpp is going to be removed from Boost.Atomic
I think that your PPC trailing fence (isync) is wrong for loads. isync should only be used after a conditional jump (if one wants acquire semantics). For loads, you need either a trailing lwsync, or a fake never-taken branch + isync.
http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2745.html
this is very helpful indeed, will fix the implementation
Your use of a single lock for seq_cst operations has given me pause, but now that I've thought about it some more, I think that this is not necessary. Per-location locks also provide sequential consistency.
yes you're right -- I guess this was guided by the mistaken idea that the actual memory accesses must be serialized (instead of just considering the observable behaviour)
There is already boost/smart_ptr/detail/spinlock_pool.hpp that you may use for the fallback - if you like.
this looks like what I need, but maybe such a thing should live under "thread" perhaps, instead of smart_ptr? Thanks for the feedback! Helge